patch-4.9.241-rt156-tizen.patch 41/272441/3
authorClark Williams <clark.williams@gmail.com>
Tue, 22 Feb 2022 19:03:47 +0000 (20:03 +0100)
committerŁukasz Stelmach <l.stelmach@samsung.com>
Mon, 21 Mar 2022 22:50:40 +0000 (23:50 +0100)
Apply patch-4.9.241-rt156 adjusted for the following commits in the history

25c6a63c469f8
6eaff2cd5830a
b7fdaa641fb95
1f998b3593797
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4b65a5db36278
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91d7a0007aa40
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60e98ef37d3dc
1a37dd20899c4
cffed7e631b56

Change-Id: I9421bdf156fa0b309833c83ec820ec1af8c710f0
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
395 files changed:
Documentation/sysrq.txt
Documentation/trace/histograms.txt [new file with mode: 0644]
MAINTAINERS
arch/Kconfig
arch/arm/Kconfig
arch/arm/include/asm/irq.h
arch/arm/include/asm/switch_to.h
arch/arm/include/asm/thread_info.h
arch/arm/kernel/asm-offsets.c
arch/arm/kernel/entry-armv.S
arch/arm/kernel/entry-common.S
arch/arm/kernel/process.c
arch/arm/kernel/signal.c
arch/arm/kernel/smp.c
arch/arm/kvm/arm.c
arch/arm/mach-exynos/platsmp.c
arch/arm/mach-hisi/platmcpm.c
arch/arm/mach-omap2/omap-smp.c
arch/arm/mach-prima2/platsmp.c
arch/arm/mach-qcom/platsmp.c
arch/arm/mach-spear/platsmp.c
arch/arm/mach-sti/platsmp.c
arch/arm/mm/fault.c
arch/arm/mm/highmem.c
arch/arm/plat-versatile/platsmp.c
arch/arm64/Kconfig
arch/arm64/crypto/Kconfig
arch/arm64/include/asm/thread_info.h
arch/arm64/kernel/asm-offsets.c
arch/arm64/kernel/entry.S
arch/arm64/kernel/signal.c
arch/mips/Kconfig
arch/powerpc/Kconfig
arch/powerpc/include/asm/thread_info.h
arch/powerpc/kernel/asm-offsets.c
arch/powerpc/kernel/entry_32.S
arch/powerpc/kernel/entry_64.S
arch/powerpc/kernel/irq.c
arch/powerpc/kernel/misc_32.S
arch/powerpc/kernel/misc_64.S
arch/powerpc/kvm/Kconfig
arch/powerpc/platforms/ps3/device-init.c
arch/sh/kernel/irq.c
arch/sparc/Kconfig
arch/sparc/kernel/irq_64.c
arch/x86/Kconfig
arch/x86/crypto/aesni-intel_glue.c
arch/x86/crypto/camellia_aesni_avx2_glue.c
arch/x86/crypto/camellia_aesni_avx_glue.c
arch/x86/crypto/cast5_avx_glue.c
arch/x86/crypto/cast6_avx_glue.c
arch/x86/crypto/chacha20_glue.c
arch/x86/crypto/glue_helper.c
arch/x86/crypto/serpent_avx2_glue.c
arch/x86/crypto/serpent_avx_glue.c
arch/x86/crypto/serpent_sse2_glue.c
arch/x86/crypto/twofish_avx_glue.c
arch/x86/entry/common.c
arch/x86/entry/entry_32.S
arch/x86/entry/entry_64.S
arch/x86/include/asm/fpu/api.h
arch/x86/include/asm/preempt.h
arch/x86/include/asm/signal.h
arch/x86/include/asm/stackprotector.h
arch/x86/include/asm/thread_info.h
arch/x86/include/asm/uv/uv_bau.h
arch/x86/kernel/acpi/boot.c
arch/x86/kernel/asm-offsets.c
arch/x86/kernel/cpu/mcheck/mce.c
arch/x86/kernel/fpu/core.c
arch/x86/kernel/irq_32.c
arch/x86/kernel/process_32.c
arch/x86/kvm/lapic.c
arch/x86/kvm/x86.c
arch/x86/mm/highmem_32.c
arch/x86/mm/iomap_32.c
arch/x86/mm/pageattr.c
arch/x86/platform/uv/tlb_uv.c
arch/x86/platform/uv/uv_time.c
block/blk-core.c
block/blk-ioc.c
block/blk-mq.c
block/blk-mq.h
block/blk-softirq.c
block/bounce.c
crypto/algapi.c
crypto/api.c
crypto/internal.h
drivers/acpi/acpica/acglobal.h
drivers/acpi/acpica/hwregs.c
drivers/acpi/acpica/hwxface.c
drivers/acpi/acpica/utmutex.c
drivers/ata/libata-sff.c
drivers/block/zram/zcomp.c
drivers/block/zram/zcomp.h
drivers/block/zram/zram_drv.c
drivers/block/zram/zram_drv.h
drivers/char/random.c
drivers/char/tpm/tpm_tis.c
drivers/clocksource/tcb_clksrc.c
drivers/clocksource/timer-atmel-pit.c
drivers/clocksource/timer-atmel-st.c
drivers/connector/cn_proc.c
drivers/cpufreq/Kconfig.x86
drivers/gpu/drm/i915/i915_gem_execbuffer.c
drivers/gpu/drm/i915/i915_gem_shrinker.c
drivers/gpu/drm/i915/i915_irq.c
drivers/gpu/drm/i915/intel_display.c
drivers/gpu/drm/i915/intel_sprite.c
drivers/gpu/drm/msm/msm_gem_shrinker.c
drivers/gpu/drm/radeon/radeon_display.c
drivers/hv/vmbus_drv.c
drivers/ide/alim15x3.c
drivers/ide/hpt366.c
drivers/ide/ide-io-std.c
drivers/ide/ide-io.c
drivers/ide/ide-iops.c
drivers/ide/ide-probe.c
drivers/ide/ide-taskfile.c
drivers/infiniband/ulp/ipoib/ipoib_multicast.c
drivers/input/gameport/gameport.c
drivers/iommu/amd_iommu.c
drivers/iommu/intel-iommu.c
drivers/iommu/iova.c
drivers/leds/trigger/Kconfig
drivers/md/bcache/Kconfig
drivers/md/dm-rq.c
drivers/md/raid5.c
drivers/md/raid5.h
drivers/misc/Kconfig
drivers/mmc/host/mmci.c
drivers/net/ethernet/3com/3c59x.c
drivers/net/wireless/bcmdhd/dhd_pno.c
drivers/net/wireless/intersil/orinoco/orinoco_usb.c
drivers/pinctrl/qcom/pinctrl-msm.c
drivers/scsi/fcoe/fcoe.c
drivers/scsi/fcoe/fcoe_ctlr.c
drivers/scsi/libfc/fc_exch.c
drivers/scsi/libsas/sas_ata.c
drivers/scsi/qla2xxx/qla_inline.h
drivers/scsi/qla2xxx/qla_isr.c
drivers/thermal/x86_pkg_temp_thermal.c
drivers/tty/serial/8250/8250_core.c
drivers/tty/serial/8250/8250_port.c
drivers/tty/serial/amba-pl011.c
drivers/tty/serial/omap-serial.c
drivers/usb/core/hcd.c
drivers/usb/gadget/function/f_fs.c
drivers/usb/gadget/legacy/inode.c
fs/aio.c
fs/autofs4/autofs_i.h
fs/autofs4/expire.c
fs/buffer.c
fs/cifs/readdir.c
fs/dcache.c
fs/eventpoll.c
fs/exec.c
fs/ext4/page-io.c
fs/fuse/dir.c
fs/inode.c
fs/locks.c
fs/namei.c
fs/namespace.c
fs/nfs/delegation.c
fs/nfs/dir.c
fs/nfs/inode.c
fs/nfs/nfs4_fs.h
fs/nfs/nfs4proc.c
fs/nfs/nfs4state.c
fs/nfs/unlink.c
fs/ntfs/aops.c
fs/proc/base.c
fs/proc/proc_sysctl.c
fs/squashfs/decompressor_multi_percpu.c
fs/timerfd.c
fs/xfs/xfs_aops.c
include/acpi/platform/aclinux.h
include/asm-generic/bug.h
include/linux/blk-mq.h
include/linux/blkdev.h
include/linux/bottom_half.h
include/linux/buffer_head.h
include/linux/cgroup-defs.h
include/linux/completion.h
include/linux/cpu.h
include/linux/dcache.h
include/linux/delay.h
include/linux/fs.h
include/linux/highmem.h
include/linux/hrtimer.h
include/linux/idr.h
include/linux/init_task.h
include/linux/interrupt.h
include/linux/irq.h
include/linux/irq_work.h
include/linux/irqdesc.h
include/linux/irqflags.h
include/linux/jbd2.h
include/linux/kdb.h
include/linux/kernel.h
include/linux/list_bl.h
include/linux/locallock.h [new file with mode: 0644]
include/linux/mm_types.h
include/linux/module.h
include/linux/mutex.h
include/linux/mutex_rt.h [new file with mode: 0644]
include/linux/netdevice.h
include/linux/netfilter/x_tables.h
include/linux/nfs_fs.h
include/linux/nfs_xdr.h
include/linux/notifier.h
include/linux/percpu-rwsem.h
include/linux/percpu.h
include/linux/pid.h
include/linux/posix-timers.h
include/linux/preempt.h
include/linux/printk.h
include/linux/radix-tree.h
include/linux/random.h
include/linux/rbtree.h
include/linux/rbtree_augmented.h
include/linux/rcu_assign_pointer.h [new file with mode: 0644]
include/linux/rcupdate.h
include/linux/rcutree.h
include/linux/rtmutex.h
include/linux/rwlock_rt.h [new file with mode: 0644]
include/linux/rwlock_types.h
include/linux/rwlock_types_rt.h [new file with mode: 0644]
include/linux/rwsem.h
include/linux/rwsem_rt.h [new file with mode: 0644]
include/linux/sched.h
include/linux/sched/rt.h
include/linux/seqlock.h
include/linux/signal.h
include/linux/skbuff.h
include/linux/smp.h
include/linux/spinlock.h
include/linux/spinlock_api_smp.h
include/linux/spinlock_rt.h [new file with mode: 0644]
include/linux/spinlock_types.h
include/linux/spinlock_types_nort.h [new file with mode: 0644]
include/linux/spinlock_types_raw.h [new file with mode: 0644]
include/linux/spinlock_types_rt.h [new file with mode: 0644]
include/linux/srcu.h
include/linux/suspend.h
include/linux/swait.h
include/linux/swap.h
include/linux/swork.h [new file with mode: 0644]
include/linux/thread_info.h
include/linux/timer.h
include/linux/trace_events.h
include/linux/uaccess.h
include/linux/uprobes.h
include/linux/vmstat.h
include/linux/wait.h
include/net/dst.h
include/net/gen_stats.h
include/net/neighbour.h
include/net/net_seq_lock.h [new file with mode: 0644]
include/net/netns/ipv4.h
include/net/sch_generic.h
include/trace/events/hist.h [new file with mode: 0644]
include/trace/events/latency_hist.h [new file with mode: 0644]
include/trace/events/sched.h
init/Kconfig
init/Makefile
init/main.c
ipc/sem.c
kernel/Kconfig.locks
kernel/Kconfig.preempt
kernel/cgroup.c
kernel/cpu.c
kernel/cpu_pm.c
kernel/cpuset.c
kernel/debug/kdb/kdb_io.c
kernel/events/core.c
kernel/exit.c
kernel/fork.c
kernel/futex.c
kernel/irq/handle.c
kernel/irq/manage.c
kernel/irq/settings.h
kernel/irq/spurious.c
kernel/irq_work.c
kernel/ksysfs.c
kernel/locking/Makefile
kernel/locking/lockdep.c
kernel/locking/locktorture.c
kernel/locking/percpu-rwsem.c
kernel/locking/rt.c [new file with mode: 0644]
kernel/locking/rtmutex-debug.c
kernel/locking/rtmutex-debug.h
kernel/locking/rtmutex.c
kernel/locking/rtmutex.h
kernel/locking/rtmutex_common.h
kernel/locking/rwsem-rt.c [new file with mode: 0644]
kernel/locking/spinlock.c
kernel/locking/spinlock_debug.c
kernel/module.c
kernel/panic.c
kernel/power/hibernate.c
kernel/power/suspend.c
kernel/printk/printk.c
kernel/ptrace.c
kernel/rcu/rcutorture.c
kernel/rcu/tree.c
kernel/rcu/tree.h
kernel/rcu/tree_plugin.h
kernel/rcu/update.c
kernel/sched/Makefile
kernel/sched/completion.c
kernel/sched/core.c
kernel/sched/deadline.c
kernel/sched/debug.c
kernel/sched/fair.c
kernel/sched/features.h
kernel/sched/rt.c
kernel/sched/sched.h
kernel/sched/swait.c
kernel/sched/swork.c [new file with mode: 0644]
kernel/signal.c
kernel/softirq.c
kernel/stop_machine.c
kernel/time/alarmtimer.c
kernel/time/hrtimer.c
kernel/time/itimer.c
kernel/time/jiffies.c
kernel/time/posix-cpu-timers.c
kernel/time/posix-timers.c
kernel/time/tick-broadcast-hrtimer.c
kernel/time/tick-common.c
kernel/time/tick-sched.c
kernel/time/timekeeping.c
kernel/time/timekeeping.h
kernel/time/timer.c
kernel/trace/Kconfig
kernel/trace/Makefile
kernel/trace/latency_hist.c [new file with mode: 0644]
kernel/trace/trace.c
kernel/trace/trace.h
kernel/trace/trace_events.c
kernel/trace/trace_irqsoff.c
kernel/trace/trace_output.c
kernel/user.c
kernel/watchdog.c
kernel/watchdog_hld.c
kernel/workqueue.c
kernel/workqueue_internal.h
lib/Kconfig
lib/debugobjects.c
lib/idr.c
lib/irq_poll.c
lib/locking-selftest.c
lib/percpu_ida.c
lib/radix-tree.c
lib/scatterlist.c
lib/smp_processor_id.c
localversion-rt [new file with mode: 0644]
mm/Kconfig
mm/backing-dev.c
mm/compaction.c
mm/filemap.c
mm/highmem.c
mm/memcontrol.c
mm/mmu_context.c
mm/page_alloc.c
mm/percpu.c
mm/slab.h
mm/slub.c
mm/swap.c
mm/truncate.c
mm/vmalloc.c
mm/vmstat.c
mm/workingset.c
mm/zsmalloc.c
net/bluetooth/hci_sock.c
net/core/dev.c
net/core/filter.c
net/core/gen_estimator.c
net/core/gen_stats.c
net/core/skbuff.c
net/core/sock.c
net/ipv4/icmp.c
net/ipv4/sysctl_net_ipv4.c
net/ipv4/tcp_ipv4.c
net/mac80211/rx.c
net/netfilter/core.c
net/packet/af_packet.c
net/rds/ib_rdma.c
net/rxrpc/security.c
net/sched/sch_api.c
net/sched/sch_generic.c
net/sunrpc/svc_xprt.c
scripts/mkcompile_h
sound/core/pcm_native.c

index 3a3b30a..9e0745c 100644 (file)
@@ -59,10 +59,17 @@ On PowerPC - Press 'ALT - Print Screen (or F13) - <command key>,
 On other - If you know of the key combos for other architectures, please
            let me know so I can add them to this section.
 
-On all -  write a character to /proc/sysrq-trigger.  e.g.:
-
+On all -  write a character to /proc/sysrq-trigger, e.g.:
                echo t > /proc/sysrq-trigger
 
+On all - Enable network SysRq by writing a cookie to icmp_echo_sysrq, e.g.
+               echo 0x01020304 >/proc/sys/net/ipv4/icmp_echo_sysrq
+        Send an ICMP echo request with this pattern plus the particular
+        SysRq command key. Example:
+               # ping -c1 -s57 -p0102030468
+        will trigger the SysRq-H (help) command.
+
+
 *  What are the 'command' keys?
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 'b'     - Will immediately reboot the system without syncing or unmounting
diff --git a/Documentation/trace/histograms.txt b/Documentation/trace/histograms.txt
new file mode 100644 (file)
index 0000000..6f2aeab
--- /dev/null
@@ -0,0 +1,186 @@
+               Using the Linux Kernel Latency Histograms
+
+
+This document gives a short explanation how to enable, configure and use
+latency histograms. Latency histograms are primarily relevant in the
+context of real-time enabled kernels (CONFIG_PREEMPT/CONFIG_PREEMPT_RT)
+and are used in the quality management of the Linux real-time
+capabilities.
+
+
+* Purpose of latency histograms
+
+A latency histogram continuously accumulates the frequencies of latency
+data. There are two types of histograms
+- potential sources of latencies
+- effective latencies
+
+
+* Potential sources of latencies
+
+Potential sources of latencies are code segments where interrupts,
+preemption or both are disabled (aka critical sections). To create
+histograms of potential sources of latency, the kernel stores the time
+stamp at the start of a critical section, determines the time elapsed
+when the end of the section is reached, and increments the frequency
+counter of that latency value - irrespective of whether any concurrently
+running process is affected by latency or not.
+- Configuration items (in the Kernel hacking/Tracers submenu)
+  CONFIG_INTERRUPT_OFF_LATENCY
+  CONFIG_PREEMPT_OFF_LATENCY
+
+
+* Effective latencies
+
+Effective latencies are actually occuring during wakeup of a process. To
+determine effective latencies, the kernel stores the time stamp when a
+process is scheduled to be woken up, and determines the duration of the
+wakeup time shortly before control is passed over to this process. Note
+that the apparent latency in user space may be somewhat longer, since the
+process may be interrupted after control is passed over to it but before
+the execution in user space takes place. Simply measuring the interval
+between enqueuing and wakeup may also not appropriate in cases when a
+process is scheduled as a result of a timer expiration. The timer may have
+missed its deadline, e.g. due to disabled interrupts, but this latency
+would not be registered. Therefore, the offsets of missed timers are
+recorded in a separate histogram. If both wakeup latency and missed timer
+offsets are configured and enabled, a third histogram may be enabled that
+records the overall latency as a sum of the timer latency, if any, and the
+wakeup latency. This histogram is called "timerandwakeup".
+- Configuration items (in the Kernel hacking/Tracers submenu)
+  CONFIG_WAKEUP_LATENCY
+  CONFIG_MISSED_TIMER_OFSETS
+
+
+* Usage
+
+The interface to the administration of the latency histograms is located
+in the debugfs file system. To mount it, either enter
+
+mount -t sysfs nodev /sys
+mount -t debugfs nodev /sys/kernel/debug
+
+from shell command line level, or add
+
+nodev  /sys                    sysfs   defaults        0 0
+nodev  /sys/kernel/debug       debugfs defaults        0 0
+
+to the file /etc/fstab. All latency histogram related files are then
+available in the directory /sys/kernel/debug/tracing/latency_hist. A
+particular histogram type is enabled by writing non-zero to the related
+variable in the /sys/kernel/debug/tracing/latency_hist/enable directory.
+Select "preemptirqsoff" for the histograms of potential sources of
+latencies and "wakeup" for histograms of effective latencies etc. The
+histogram data - one per CPU - are available in the files
+
+/sys/kernel/debug/tracing/latency_hist/preemptoff/CPUx
+/sys/kernel/debug/tracing/latency_hist/irqsoff/CPUx
+/sys/kernel/debug/tracing/latency_hist/preemptirqsoff/CPUx
+/sys/kernel/debug/tracing/latency_hist/wakeup/CPUx
+/sys/kernel/debug/tracing/latency_hist/wakeup/sharedprio/CPUx
+/sys/kernel/debug/tracing/latency_hist/missed_timer_offsets/CPUx
+/sys/kernel/debug/tracing/latency_hist/timerandwakeup/CPUx
+
+The histograms are reset by writing non-zero to the file "reset" in a
+particular latency directory. To reset all latency data, use
+
+#!/bin/sh
+
+TRACINGDIR=/sys/kernel/debug/tracing
+HISTDIR=$TRACINGDIR/latency_hist
+
+if test -d $HISTDIR
+then
+  cd $HISTDIR
+  for i in `find . | grep /reset$`
+  do
+    echo 1 >$i
+  done
+fi
+
+
+* Data format
+
+Latency data are stored with a resolution of one microsecond. The
+maximum latency is 10,240 microseconds. The data are only valid, if the
+overflow register is empty. Every output line contains the latency in
+microseconds in the first row and the number of samples in the second
+row. To display only lines with a positive latency count, use, for
+example,
+
+grep -v " 0$" /sys/kernel/debug/tracing/latency_hist/preemptoff/CPU0
+
+#Minimum latency: 0 microseconds.
+#Average latency: 0 microseconds.
+#Maximum latency: 25 microseconds.
+#Total samples: 3104770694
+#There are 0 samples greater or equal than 10240 microseconds
+#usecs          samples
+    0        2984486876
+    1          49843506
+    2          58219047
+    3           5348126
+    4           2187960
+    5           3388262
+    6            959289
+    7            208294
+    8             40420
+    9              4485
+   10             14918
+   11             18340
+   12             25052
+   13             19455
+   14              5602
+   15               969
+   16                47
+   17                18
+   18                14
+   19                 1
+   20                 3
+   21                 2
+   22                 5
+   23                 2
+   25                 1
+
+
+* Wakeup latency of a selected process
+
+To only collect wakeup latency data of a particular process, write the
+PID of the requested process to
+
+/sys/kernel/debug/tracing/latency_hist/wakeup/pid
+
+PIDs are not considered, if this variable is set to 0.
+
+
+* Details of the process with the highest wakeup latency so far
+
+Selected data of the process that suffered from the highest wakeup
+latency that occurred in a particular CPU are available in the file
+
+/sys/kernel/debug/tracing/latency_hist/wakeup/max_latency-CPUx.
+
+In addition, other relevant system data at the time when the
+latency occurred are given.
+
+The format of the data is (all in one line):
+<PID> <Priority> <Latency> (<Timeroffset>) <Command> \
+<- <PID> <Priority> <Command> <Timestamp>
+
+The value of <Timeroffset> is only relevant in the combined timer
+and wakeup latency recording. In the wakeup recording, it is
+always 0, in the missed_timer_offsets recording, it is the same
+as <Latency>.
+
+When retrospectively searching for the origin of a latency and
+tracing was not enabled, it may be helpful to know the name and
+some basic data of the task that (finally) was switching to the
+late real-tlme task. In addition to the victim's data, also the
+data of the possible culprit are therefore displayed after the
+"<-" symbol.
+
+Finally, the timestamp of the time when the latency occurred
+in <seconds>.<microseconds> after the most recent system boot
+is provided.
+
+These data are also reset when the wakeup histogram is reset.
index 1aace7e..3d09a38 100644 (file)
@@ -5196,6 +5196,23 @@ F:       fs/fuse/
 F:     include/uapi/linux/fuse.h
 F:     Documentation/filesystems/fuse.txt
 
+FUTEX SUBSYSTEM
+M:     Thomas Gleixner <tglx@linutronix.de>
+M:     Ingo Molnar <mingo@redhat.com>
+R:     Peter Zijlstra <peterz@infradead.org>
+R:     Darren Hart <dvhart@infradead.org>
+L:     linux-kernel@vger.kernel.org
+T:     git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git locking/core
+S:     Maintained
+F:     kernel/futex.c
+F:     kernel/futex_compat.c
+F:     include/asm-generic/futex.h
+F:     include/linux/futex.h
+F:     include/uapi/linux/futex.h
+F:     tools/testing/selftests/futex/
+F:     tools/perf/bench/futex*
+F:     Documentation/*futex*
+
 FUTURE DOMAIN TMC-16x0 SCSI DRIVER (16-bit)
 M:     Rik Faith <faith@cs.unc.edu>
 L:     linux-scsi@vger.kernel.org
index 20fd67d..039746b 100644 (file)
@@ -12,6 +12,7 @@ config OPROFILE
        tristate "OProfile system profiling"
        depends on PROFILING
        depends on HAVE_OPROFILE
+       depends on !PREEMPT_RT_FULL
        select RING_BUFFER
        select RING_BUFFER_ALLOW_SWAP
        help
@@ -55,6 +56,7 @@ config KPROBES
 config JUMP_LABEL
        bool "Optimize very unlikely/likely branches"
        depends on HAVE_ARCH_JUMP_LABEL
+       depends on (!INTERRUPT_OFF_HIST && !PREEMPT_OFF_HIST && !WAKEUP_LATENCY_HIST && !MISSED_TIMER_OFFSETS_HIST)
        help
          This option enables a transparent branch optimization that
         makes certain almost-always-true or almost-always-false branch
index 37bf9aa..a6fd312 100644 (file)
@@ -36,7 +36,7 @@ config ARM
        select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT)
        select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
        select HAVE_ARCH_HARDENED_USERCOPY
-       select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
+       select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU && !PREEMPT_RT_BASE
        select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
        select HAVE_ARCH_MMAP_RND_BITS if MMU
        select HAVE_ARCH_SECCOMP_FILTER if (AEABI && !OABI_COMPAT)
@@ -75,6 +75,7 @@ config ARM
        select HAVE_PERF_EVENTS
        select HAVE_PERF_REGS
        select HAVE_PERF_USER_STACK_DUMP
+       select HAVE_PREEMPT_LAZY
        select HAVE_RCU_TABLE_FREE if (SMP && ARM_LPAE)
        select HAVE_REGS_AND_STACK_ACCESS_API
        select HAVE_SYSCALL_TRACEPOINTS
@@ -2182,7 +2183,7 @@ config NEON
 
 config KERNEL_MODE_NEON
        bool "Support for NEON in kernel mode"
-       depends on NEON && AEABI
+       depends on NEON && AEABI && !PREEMPT_RT_BASE
        help
          Say Y to include support for NEON in kernel mode.
 
index 61e1d08..0893b01 100644 (file)
@@ -22,6 +22,8 @@
 #endif
 
 #ifndef __ASSEMBLY__
+#include <linux/cpumask.h>
+
 struct irqaction;
 struct pt_regs;
 
index 12ebfcc..c962084 100644 (file)
@@ -3,6 +3,13 @@
 
 #include <linux/thread_info.h>
 
+#if defined CONFIG_PREEMPT_RT_FULL && defined CONFIG_HIGHMEM
+void switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p);
+#else
+static inline void
+switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p) { }
+#endif
+
 /*
  * For v7 SMP cores running a preemptible kernel we may be pre-empted
  * during a TLB maintenance operation, so execute an inner-shareable dsb
@@ -25,6 +32,7 @@ extern struct task_struct *__switch_to(struct task_struct *, struct thread_info
 #define switch_to(prev,next,last)                                      \
 do {                                                                   \
        __complete_pending_tlbi();                                      \
+       switch_kmaps(prev, next);                                       \
        last = __switch_to(prev,task_thread_info(prev), task_thread_info(next));        \
 } while (0)
 
index 935ec19..3c624b0 100644 (file)
@@ -63,6 +63,7 @@ struct cpu_context_save {
 struct thread_info {
        unsigned long           flags;          /* low level flags */
        int                     preempt_count;  /* 0 => preemptable, <0 => bug */
+       int                     preempt_lazy_count; /* 0 => preemptable, <0 => bug */
        mm_segment_t            addr_limit;     /* address limit */
        struct task_struct      *task;          /* main task structure */
        __u32                   cpu;            /* cpu */
@@ -165,7 +166,8 @@ extern int vfp_restore_user_hwstate(struct user_vfp *,
 #define TIF_SYSCALL_TRACE      4       /* syscall trace active */
 #define TIF_SYSCALL_AUDIT      5       /* syscall auditing active */
 #define TIF_SYSCALL_TRACEPOINT 6       /* syscall tracepoint instrumentation */
-#define TIF_SECCOMP            7       /* seccomp syscall filtering active */
+#define TIF_SECCOMP            8       /* seccomp syscall filtering active */
+#define TIF_NEED_RESCHED_LAZY  7
 
 #define TIF_NOHZ               12      /* in adaptive nohz mode */
 #define TIF_USING_IWMMXT       17
@@ -175,6 +177,7 @@ extern int vfp_restore_user_hwstate(struct user_vfp *,
 #define _TIF_SIGPENDING                (1 << TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED      (1 << TIF_NEED_RESCHED)
 #define _TIF_NOTIFY_RESUME     (1 << TIF_NOTIFY_RESUME)
+#define _TIF_NEED_RESCHED_LAZY (1 << TIF_NEED_RESCHED_LAZY)
 #define _TIF_UPROBE            (1 << TIF_UPROBE)
 #define _TIF_SYSCALL_TRACE     (1 << TIF_SYSCALL_TRACE)
 #define _TIF_SYSCALL_AUDIT     (1 << TIF_SYSCALL_AUDIT)
@@ -190,7 +193,8 @@ extern int vfp_restore_user_hwstate(struct user_vfp *,
  * Change these and you break ASM code in entry-common.S
  */
 #define _TIF_WORK_MASK         (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \
-                                _TIF_NOTIFY_RESUME | _TIF_UPROBE)
+                                _TIF_NOTIFY_RESUME | _TIF_UPROBE | \
+                                _TIF_NEED_RESCHED_LAZY)
 
 #endif /* __KERNEL__ */
 #endif /* __ASM_ARM_THREAD_INFO_H */
index 365842d..5fb69a2 100644 (file)
@@ -65,6 +65,7 @@ int main(void)
   BLANK();
   DEFINE(TI_FLAGS,             offsetof(struct thread_info, flags));
   DEFINE(TI_PREEMPT,           offsetof(struct thread_info, preempt_count));
+  DEFINE(TI_PREEMPT_LAZY,      offsetof(struct thread_info, preempt_lazy_count));
   DEFINE(TI_ADDR_LIMIT,                offsetof(struct thread_info, addr_limit));
   DEFINE(TI_TASK,              offsetof(struct thread_info, task));
   DEFINE(TI_CPU,               offsetof(struct thread_info, cpu));
index 8ca5fc7..db68e4e 100644 (file)
@@ -333,11 +333,18 @@ __irq_svc:
 
 #ifdef CONFIG_PREEMPT
        ldr     r8, [tsk, #TI_PREEMPT]          @ get preempt count
-       ldr     r0, [tsk, #TI_FLAGS]            @ get flags
        teq     r8, #0                          @ if preempt count != 0
+       bne     1f                              @ return from exeption
+       ldr     r0, [tsk, #TI_FLAGS]            @ get flags
+       tst     r0, #_TIF_NEED_RESCHED          @ if NEED_RESCHED is set
+       blne    svc_preempt                     @ preempt!
+
+       ldr     r8, [tsk, #TI_PREEMPT_LAZY]     @ get preempt lazy count
+       teq     r8, #0                          @ if preempt lazy count != 0
        movne   r0, #0                          @ force flags to 0
-       tst     r0, #_TIF_NEED_RESCHED
+       tst     r0, #_TIF_NEED_RESCHED_LAZY
        blne    svc_preempt
+1:
 #endif
 
        svc_exit r5, irq = 1                    @ return from exception
@@ -352,8 +359,14 @@ svc_preempt:
 1:     bl      preempt_schedule_irq            @ irq en/disable is done inside
        ldr     r0, [tsk, #TI_FLAGS]            @ get new tasks TI_FLAGS
        tst     r0, #_TIF_NEED_RESCHED
+       bne     1b
+       tst     r0, #_TIF_NEED_RESCHED_LAZY
        reteq   r8                              @ go again
-       b       1b
+       ldr     r0, [tsk, #TI_PREEMPT_LAZY]     @ get preempt lazy count
+       teq     r0, #0                          @ if preempt lazy count != 0
+       beq     1b
+       ret     r8                              @ go again
+
 #endif
 
 __und_fault:
index 178a2a9..97a93bd 100644 (file)
@@ -37,7 +37,9 @@ __ret_fast_syscall:
  UNWIND(.cantunwind    )
        disable_irq_notrace                     @ disable interrupts
        ldr     r1, [tsk, #TI_FLAGS]            @ re-check for syscall tracing
-       tst     r1, #_TIF_SYSCALL_WORK | _TIF_WORK_MASK
+       tst     r1, #((_TIF_SYSCALL_WORK | _TIF_WORK_MASK) & ~_TIF_SECCOMP)
+       bne     fast_work_pending
+       tst     r1, #_TIF_SECCOMP
        bne     fast_work_pending
 
        /* perform architecture specific actions before user return */
@@ -64,8 +66,11 @@ __ret_fast_syscall:
        str     r0, [sp, #S_R0 + S_OFF]!        @ save returned r0
        disable_irq_notrace                     @ disable interrupts
        ldr     r1, [tsk, #TI_FLAGS]            @ re-check for syscall tracing
-       tst     r1, #_TIF_SYSCALL_WORK | _TIF_WORK_MASK
+       tst     r1, #((_TIF_SYSCALL_WORK | _TIF_WORK_MASK) & ~_TIF_SECCOMP)
+       bne     do_slower_path
+       tst     r1, #_TIF_SECCOMP
        beq     no_work_pending
+do_slower_path:
  UNWIND(.fnend         )
 ENDPROC(ret_fast_syscall)
 
index 7468ede..ee2e8ec 100644 (file)
@@ -651,6 +651,30 @@ unsigned long arch_randomize_brk(struct mm_struct *mm)
 }
 
 #ifdef CONFIG_MMU
+/*
+ * CONFIG_SPLIT_PTLOCK_CPUS results in a page->ptl lock.  If the lock is not
+ * initialized by pgtable_page_ctor() then a coredump of the vector page will
+ * fail.
+ */
+static int __init vectors_user_mapping_init_page(void)
+{
+       struct page *page;
+       unsigned long addr = 0xffff0000;
+       pgd_t *pgd;
+       pud_t *pud;
+       pmd_t *pmd;
+
+       pgd = pgd_offset_k(addr);
+       pud = pud_offset(pgd, addr);
+       pmd = pmd_offset(pud, addr);
+       page = pmd_page(*(pmd));
+
+       pgtable_page_ctor(page);
+
+       return 0;
+}
+late_initcall(vectors_user_mapping_init_page);
+
 #ifdef CONFIG_KUSER_HELPERS
 /*
  * The vectors page is always readable from user space for the
index 0a066f0..295d96a 100644 (file)
@@ -581,7 +581,8 @@ do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall)
         */
        trace_hardirqs_off();
        do {
-               if (likely(thread_flags & _TIF_NEED_RESCHED)) {
+               if (likely(thread_flags & (_TIF_NEED_RESCHED |
+                                          _TIF_NEED_RESCHED_LAZY))) {
                        schedule();
                } else {
                        if (unlikely(!user_mode(regs)))
index 0a5704c..1658af6 100644 (file)
@@ -269,8 +269,6 @@ int __cpu_disable(void)
        flush_cache_louis();
        local_flush_tlb_all();
 
-       clear_tasks_mm_cpumask(cpu);
-
        return 0;
 }
 
@@ -286,6 +284,9 @@ void __cpu_die(unsigned int cpu)
                pr_err("CPU%u: cpu didn't die\n", cpu);
                return;
        }
+
+       clear_tasks_mm_cpumask(cpu);
+
        pr_notice("CPU%u: shutdown\n", cpu);
 
        /*
index dfc00a5..37bb67f 100644 (file)
@@ -619,7 +619,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
                 * involves poking the GIC, which must be done in a
                 * non-preemptible context.
                 */
-               preempt_disable();
+               migrate_disable();
                kvm_pmu_flush_hwstate(vcpu);
                kvm_timer_flush_hwstate(vcpu);
                kvm_vgic_flush_hwstate(vcpu);
@@ -640,7 +640,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
                        kvm_pmu_sync_hwstate(vcpu);
                        kvm_timer_sync_hwstate(vcpu);
                        kvm_vgic_sync_hwstate(vcpu);
-                       preempt_enable();
+                       migrate_enable();
                        continue;
                }
 
@@ -696,7 +696,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
 
                kvm_vgic_sync_hwstate(vcpu);
 
-               preempt_enable();
+               migrate_enable();
 
                ret = handle_exit(vcpu, run, ret);
        }
index 98ffe1e..df9769d 100644 (file)
@@ -229,7 +229,7 @@ static void __iomem *scu_base_addr(void)
        return (void __iomem *)(S5P_VA_SCU);
 }
 
-static DEFINE_SPINLOCK(boot_lock);
+static DEFINE_RAW_SPINLOCK(boot_lock);
 
 static void exynos_secondary_init(unsigned int cpu)
 {
@@ -242,8 +242,8 @@ static void exynos_secondary_init(unsigned int cpu)
        /*
         * Synchronise with the boot thread.
         */
-       spin_lock(&boot_lock);
-       spin_unlock(&boot_lock);
+       raw_spin_lock(&boot_lock);
+       raw_spin_unlock(&boot_lock);
 }
 
 int exynos_set_boot_addr(u32 core_id, unsigned long boot_addr)
@@ -307,7 +307,7 @@ static int exynos_boot_secondary(unsigned int cpu, struct task_struct *idle)
         * Set synchronisation state between this boot processor
         * and the secondary one
         */
-       spin_lock(&boot_lock);
+       raw_spin_lock(&boot_lock);
 
        /*
         * The secondary processor is waiting to be released from
@@ -334,7 +334,7 @@ static int exynos_boot_secondary(unsigned int cpu, struct task_struct *idle)
 
                if (timeout == 0) {
                        printk(KERN_ERR "cpu1 power enable failed");
-                       spin_unlock(&boot_lock);
+                       raw_spin_unlock(&boot_lock);
                        return -ETIMEDOUT;
                }
        }
@@ -380,7 +380,7 @@ static int exynos_boot_secondary(unsigned int cpu, struct task_struct *idle)
         * calibrations, then wait for it to finish
         */
 fail:
-       spin_unlock(&boot_lock);
+       raw_spin_unlock(&boot_lock);
 
        return pen_release != -1 ? ret : 0;
 }
index 4b653a8..b03d5a9 100644 (file)
@@ -61,7 +61,7 @@
 
 static void __iomem *sysctrl, *fabric;
 static int hip04_cpu_table[HIP04_MAX_CLUSTERS][HIP04_MAX_CPUS_PER_CLUSTER];
-static DEFINE_SPINLOCK(boot_lock);
+static DEFINE_RAW_SPINLOCK(boot_lock);
 static u32 fabric_phys_addr;
 /*
  * [0]: bootwrapper physical address
@@ -113,7 +113,7 @@ static int hip04_boot_secondary(unsigned int l_cpu, struct task_struct *idle)
        if (cluster >= HIP04_MAX_CLUSTERS || cpu >= HIP04_MAX_CPUS_PER_CLUSTER)
                return -EINVAL;
 
-       spin_lock_irq(&boot_lock);
+       raw_spin_lock_irq(&boot_lock);
 
        if (hip04_cpu_table[cluster][cpu])
                goto out;
@@ -147,7 +147,7 @@ static int hip04_boot_secondary(unsigned int l_cpu, struct task_struct *idle)
 
 out:
        hip04_cpu_table[cluster][cpu]++;
-       spin_unlock_irq(&boot_lock);
+       raw_spin_unlock_irq(&boot_lock);
 
        return 0;
 }
@@ -162,11 +162,11 @@ static void hip04_cpu_die(unsigned int l_cpu)
        cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
        cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
 
-       spin_lock(&boot_lock);
+       raw_spin_lock(&boot_lock);
        hip04_cpu_table[cluster][cpu]--;
        if (hip04_cpu_table[cluster][cpu] == 1) {
                /* A power_up request went ahead of us. */
-               spin_unlock(&boot_lock);
+               raw_spin_unlock(&boot_lock);
                return;
        } else if (hip04_cpu_table[cluster][cpu] > 1) {
                pr_err("Cluster %d CPU%d boots multiple times\n", cluster, cpu);
@@ -174,7 +174,7 @@ static void hip04_cpu_die(unsigned int l_cpu)
        }
 
        last_man = hip04_cluster_is_down(cluster);
-       spin_unlock(&boot_lock);
+       raw_spin_unlock(&boot_lock);
        if (last_man) {
                /* Since it's Cortex A15, disable L2 prefetching. */
                asm volatile(
@@ -203,7 +203,7 @@ static int hip04_cpu_kill(unsigned int l_cpu)
               cpu >= HIP04_MAX_CPUS_PER_CLUSTER);
 
        count = TIMEOUT_MSEC / POLL_MSEC;
-       spin_lock_irq(&boot_lock);
+       raw_spin_lock_irq(&boot_lock);
        for (tries = 0; tries < count; tries++) {
                if (hip04_cpu_table[cluster][cpu])
                        goto err;
@@ -211,10 +211,10 @@ static int hip04_cpu_kill(unsigned int l_cpu)
                data = readl_relaxed(sysctrl + SC_CPU_RESET_STATUS(cluster));
                if (data & CORE_WFI_STATUS(cpu))
                        break;
-               spin_unlock_irq(&boot_lock);
+               raw_spin_unlock_irq(&boot_lock);
                /* Wait for clean L2 when the whole cluster is down. */
                msleep(POLL_MSEC);
-               spin_lock_irq(&boot_lock);
+               raw_spin_lock_irq(&boot_lock);
        }
        if (tries >= count)
                goto err;
@@ -231,10 +231,10 @@ static int hip04_cpu_kill(unsigned int l_cpu)
                goto err;
        if (hip04_cluster_is_down(cluster))
                hip04_set_snoop_filter(cluster, 0);
-       spin_unlock_irq(&boot_lock);
+       raw_spin_unlock_irq(&boot_lock);
        return 1;
 err:
-       spin_unlock_irq(&boot_lock);
+       raw_spin_unlock_irq(&boot_lock);
        return 0;
 }
 #endif
index f7f36da..7e865f1 100644 (file)
@@ -64,7 +64,7 @@ static const struct omap_smp_config omap5_cfg __initconst = {
        .startup_addr = omap5_secondary_startup,
 };
 
-static DEFINE_SPINLOCK(boot_lock);
+static DEFINE_RAW_SPINLOCK(boot_lock);
 
 void __iomem *omap4_get_scu_base(void)
 {
@@ -172,8 +172,8 @@ static void omap4_secondary_init(unsigned int cpu)
        /*
         * Synchronise with the boot thread.
         */
-       spin_lock(&boot_lock);
-       spin_unlock(&boot_lock);
+       raw_spin_lock(&boot_lock);
+       raw_spin_unlock(&boot_lock);
 }
 
 static int omap4_boot_secondary(unsigned int cpu, struct task_struct *idle)
@@ -187,7 +187,7 @@ static int omap4_boot_secondary(unsigned int cpu, struct task_struct *idle)
         * Set synchronisation state between this boot processor
         * and the secondary one
         */
-       spin_lock(&boot_lock);
+       raw_spin_lock(&boot_lock);
 
        /*
         * Update the AuxCoreBoot0 with boot state for secondary core.
@@ -264,7 +264,7 @@ static int omap4_boot_secondary(unsigned int cpu, struct task_struct *idle)
         * Now the secondary core is starting up let it run its
         * calibrations, then wait for it to finish
         */
-       spin_unlock(&boot_lock);
+       raw_spin_unlock(&boot_lock);
 
        return 0;
 }
index 0875b99..18b6d98 100644 (file)
@@ -22,7 +22,7 @@
 
 static void __iomem *clk_base;
 
-static DEFINE_SPINLOCK(boot_lock);
+static DEFINE_RAW_SPINLOCK(boot_lock);
 
 static void sirfsoc_secondary_init(unsigned int cpu)
 {
@@ -36,8 +36,8 @@ static void sirfsoc_secondary_init(unsigned int cpu)
        /*
         * Synchronise with the boot thread.
         */
-       spin_lock(&boot_lock);
-       spin_unlock(&boot_lock);
+       raw_spin_lock(&boot_lock);
+       raw_spin_unlock(&boot_lock);
 }
 
 static const struct of_device_id clk_ids[]  = {
@@ -75,7 +75,7 @@ static int sirfsoc_boot_secondary(unsigned int cpu, struct task_struct *idle)
        /* make sure write buffer is drained */
        mb();
 
-       spin_lock(&boot_lock);
+       raw_spin_lock(&boot_lock);
 
        /*
         * The secondary processor is waiting to be released from
@@ -107,7 +107,7 @@ static int sirfsoc_boot_secondary(unsigned int cpu, struct task_struct *idle)
         * now the secondary core is starting up let it run its
         * calibrations, then wait for it to finish
         */
-       spin_unlock(&boot_lock);
+       raw_spin_unlock(&boot_lock);
 
        return pen_release != -1 ? -ENOSYS : 0;
 }
index 5494c9e..e8ce157 100644 (file)
@@ -46,7 +46,7 @@
 
 extern void secondary_startup_arm(void);
 
-static DEFINE_SPINLOCK(boot_lock);
+static DEFINE_RAW_SPINLOCK(boot_lock);
 
 #ifdef CONFIG_HOTPLUG_CPU
 static void qcom_cpu_die(unsigned int cpu)
@@ -60,8 +60,8 @@ static void qcom_secondary_init(unsigned int cpu)
        /*
         * Synchronise with the boot thread.
         */
-       spin_lock(&boot_lock);
-       spin_unlock(&boot_lock);
+       raw_spin_lock(&boot_lock);
+       raw_spin_unlock(&boot_lock);
 }
 
 static int scss_release_secondary(unsigned int cpu)
@@ -284,7 +284,7 @@ static int qcom_boot_secondary(unsigned int cpu, int (*func)(unsigned int))
         * set synchronisation state between this boot processor
         * and the secondary one
         */
-       spin_lock(&boot_lock);
+       raw_spin_lock(&boot_lock);
 
        /*
         * Send the secondary CPU a soft interrupt, thereby causing
@@ -297,7 +297,7 @@ static int qcom_boot_secondary(unsigned int cpu, int (*func)(unsigned int))
         * now the secondary core is starting up let it run its
         * calibrations, then wait for it to finish
         */
-       spin_unlock(&boot_lock);
+       raw_spin_unlock(&boot_lock);
 
        return ret;
 }
index 8d1e2d5..7fa56cc 100644 (file)
@@ -32,7 +32,7 @@ static void write_pen_release(int val)
        sync_cache_w(&pen_release);
 }
 
-static DEFINE_SPINLOCK(boot_lock);
+static DEFINE_RAW_SPINLOCK(boot_lock);
 
 static void __iomem *scu_base = IOMEM(VA_SCU_BASE);
 
@@ -47,8 +47,8 @@ static void spear13xx_secondary_init(unsigned int cpu)
        /*
         * Synchronise with the boot thread.
         */
-       spin_lock(&boot_lock);
-       spin_unlock(&boot_lock);
+       raw_spin_lock(&boot_lock);
+       raw_spin_unlock(&boot_lock);
 }
 
 static int spear13xx_boot_secondary(unsigned int cpu, struct task_struct *idle)
@@ -59,7 +59,7 @@ static int spear13xx_boot_secondary(unsigned int cpu, struct task_struct *idle)
         * set synchronisation state between this boot processor
         * and the secondary one
         */
-       spin_lock(&boot_lock);
+       raw_spin_lock(&boot_lock);
 
        /*
         * The secondary processor is waiting to be released from
@@ -84,7 +84,7 @@ static int spear13xx_boot_secondary(unsigned int cpu, struct task_struct *idle)
         * now the secondary core is starting up let it run its
         * calibrations, then wait for it to finish
         */
-       spin_unlock(&boot_lock);
+       raw_spin_unlock(&boot_lock);
 
        return pen_release != -1 ? -ENOSYS : 0;
 }
index ea5a227..b988e08 100644 (file)
@@ -35,7 +35,7 @@ static void write_pen_release(int val)
        sync_cache_w(&pen_release);
 }
 
-static DEFINE_SPINLOCK(boot_lock);
+static DEFINE_RAW_SPINLOCK(boot_lock);
 
 static void sti_secondary_init(unsigned int cpu)
 {
@@ -48,8 +48,8 @@ static void sti_secondary_init(unsigned int cpu)
        /*
         * Synchronise with the boot thread.
         */
-       spin_lock(&boot_lock);
-       spin_unlock(&boot_lock);
+       raw_spin_lock(&boot_lock);
+       raw_spin_unlock(&boot_lock);
 }
 
 static int sti_boot_secondary(unsigned int cpu, struct task_struct *idle)
@@ -60,7 +60,7 @@ static int sti_boot_secondary(unsigned int cpu, struct task_struct *idle)
         * set synchronisation state between this boot processor
         * and the secondary one
         */
-       spin_lock(&boot_lock);
+       raw_spin_lock(&boot_lock);
 
        /*
         * The secondary processor is waiting to be released from
@@ -91,7 +91,7 @@ static int sti_boot_secondary(unsigned int cpu, struct task_struct *idle)
         * now the secondary core is starting up let it run its
         * calibrations, then wait for it to finish
         */
-       spin_unlock(&boot_lock);
+       raw_spin_unlock(&boot_lock);
 
        return pen_release != -1 ? -ENOSYS : 0;
 }
index e77822a..d365083 100644 (file)
@@ -528,6 +528,9 @@ do_translation_fault(unsigned long addr, unsigned int fsr,
        if (addr < TASK_SIZE)
                return do_page_fault(addr, fsr, regs);
 
+       if (interrupts_enabled(regs))
+               local_irq_enable();
+
        if (user_mode(regs))
                goto bad_area;
 
@@ -595,6 +598,9 @@ do_translation_fault(unsigned long addr, unsigned int fsr,
 static int
 do_sect_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
 {
+       if (interrupts_enabled(regs))
+               local_irq_enable();
+
        do_bad_area(addr, fsr, regs);
        return 0;
 }
index d02f818..542692d 100644 (file)
@@ -34,6 +34,11 @@ static inline pte_t get_fixmap_pte(unsigned long vaddr)
        return *ptep;
 }
 
+static unsigned int fixmap_idx(int type)
+{
+       return FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
+}
+
 void *kmap(struct page *page)
 {
        might_sleep();
@@ -54,12 +59,13 @@ EXPORT_SYMBOL(kunmap);
 
 void *kmap_atomic(struct page *page)
 {
+       pte_t pte = mk_pte(page, kmap_prot);
        unsigned int idx;
        unsigned long vaddr;
        void *kmap;
        int type;
 
-       preempt_disable();
+       preempt_disable_nort();
        pagefault_disable();
        if (!PageHighMem(page))
                return page_address(page);
@@ -79,7 +85,7 @@ void *kmap_atomic(struct page *page)
 
        type = kmap_atomic_idx_push();
 
-       idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
+       idx = fixmap_idx(type);
        vaddr = __fix_to_virt(idx);
 #ifdef CONFIG_DEBUG_HIGHMEM
        /*
@@ -93,7 +99,10 @@ void *kmap_atomic(struct page *page)
         * in place, so the contained TLB flush ensures the TLB is updated
         * with the new mapping.
         */
-       set_fixmap_pte(idx, mk_pte(page, kmap_prot));
+#ifdef CONFIG_PREEMPT_RT_FULL
+       current->kmap_pte[type] = pte;
+#endif
+       set_fixmap_pte(idx, pte);
 
        return (void *)vaddr;
 }
@@ -106,44 +115,75 @@ void __kunmap_atomic(void *kvaddr)
 
        if (kvaddr >= (void *)FIXADDR_START) {
                type = kmap_atomic_idx();
-               idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
+               idx = fixmap_idx(type);
 
                if (cache_is_vivt())
                        __cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE);
+#ifdef CONFIG_PREEMPT_RT_FULL
+               current->kmap_pte[type] = __pte(0);
+#endif
 #ifdef CONFIG_DEBUG_HIGHMEM
                BUG_ON(vaddr != __fix_to_virt(idx));
-               set_fixmap_pte(idx, __pte(0));
 #else
                (void) idx;  /* to kill a warning */
 #endif
+               set_fixmap_pte(idx, __pte(0));
                kmap_atomic_idx_pop();
        } else if (vaddr >= PKMAP_ADDR(0) && vaddr < PKMAP_ADDR(LAST_PKMAP)) {
                /* this address was obtained through kmap_high_get() */
                kunmap_high(pte_page(pkmap_page_table[PKMAP_NR(vaddr)]));
        }
        pagefault_enable();
-       preempt_enable();
+       preempt_enable_nort();
 }
 EXPORT_SYMBOL(__kunmap_atomic);
 
 void *kmap_atomic_pfn(unsigned long pfn)
 {
+       pte_t pte = pfn_pte(pfn, kmap_prot);
        unsigned long vaddr;
        int idx, type;
        struct page *page = pfn_to_page(pfn);
 
-       preempt_disable();
+       preempt_disable_nort();
        pagefault_disable();
        if (!PageHighMem(page))
                return page_address(page);
 
        type = kmap_atomic_idx_push();
-       idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
+       idx = fixmap_idx(type);
        vaddr = __fix_to_virt(idx);
 #ifdef CONFIG_DEBUG_HIGHMEM
        BUG_ON(!pte_none(get_fixmap_pte(vaddr)));
 #endif
-       set_fixmap_pte(idx, pfn_pte(pfn, kmap_prot));
+#ifdef CONFIG_PREEMPT_RT_FULL
+       current->kmap_pte[type] = pte;
+#endif
+       set_fixmap_pte(idx, pte);
 
        return (void *)vaddr;
 }
+#if defined CONFIG_PREEMPT_RT_FULL
+void switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p)
+{
+       int i;
+
+       /*
+        * Clear @prev's kmap_atomic mappings
+        */
+       for (i = 0; i < prev_p->kmap_idx; i++) {
+               int idx = fixmap_idx(i);
+
+               set_fixmap_pte(idx, __pte(0));
+       }
+       /*
+        * Restore @next_p's kmap_atomic mappings
+        */
+       for (i = 0; i < next_p->kmap_idx; i++) {
+               int idx = fixmap_idx(i);
+
+               if (!pte_none(next_p->kmap_pte[i]))
+                       set_fixmap_pte(idx, next_p->kmap_pte[i]);
+       }
+}
+#endif
index c236651..6b60f58 100644 (file)
@@ -32,7 +32,7 @@ static void write_pen_release(int val)
        sync_cache_w(&pen_release);
 }
 
-static DEFINE_SPINLOCK(boot_lock);
+static DEFINE_RAW_SPINLOCK(boot_lock);
 
 void versatile_secondary_init(unsigned int cpu)
 {
@@ -45,8 +45,8 @@ void versatile_secondary_init(unsigned int cpu)
        /*
         * Synchronise with the boot thread.
         */
-       spin_lock(&boot_lock);
-       spin_unlock(&boot_lock);
+       raw_spin_lock(&boot_lock);
+       raw_spin_unlock(&boot_lock);
 }
 
 int versatile_boot_secondary(unsigned int cpu, struct task_struct *idle)
@@ -57,7 +57,7 @@ int versatile_boot_secondary(unsigned int cpu, struct task_struct *idle)
         * Set synchronisation state between this boot processor
         * and the secondary one
         */
-       spin_lock(&boot_lock);
+       raw_spin_lock(&boot_lock);
 
        /*
         * This is really belt and braces; we hold unintended secondary
@@ -87,7 +87,7 @@ int versatile_boot_secondary(unsigned int cpu, struct task_struct *idle)
         * now the secondary core is starting up let it run its
         * calibrations, then wait for it to finish
         */
-       spin_unlock(&boot_lock);
+       raw_spin_unlock(&boot_lock);
 
        return pen_release != -1 ? -ENOSYS : 0;
 }
index 70ae7f4..a400b01 100644 (file)
@@ -92,6 +92,7 @@ config ARM64
        select HAVE_PERF_EVENTS
        select HAVE_PERF_REGS
        select HAVE_PERF_USER_STACK_DUMP
+       select HAVE_PREEMPT_LAZY
        select HAVE_REGS_AND_STACK_ACCESS_API
        select HAVE_RCU_TABLE_FREE
        select HAVE_SYSCALL_TRACEPOINTS
@@ -720,7 +721,7 @@ config XEN_DOM0
 
 config XEN
        bool "Xen guest support on ARM64"
-       depends on ARM64 && OF
+       depends on ARM64 && OF && !PREEMPT_RT_FULL
        select SWIOTLB_XEN
        select PARAVIRT
        help
index 2b10984..b85a3b0 100644 (file)
@@ -10,41 +10,41 @@ if ARM64_CRYPTO
 
 config CRYPTO_SHA1_ARM64_CE
        tristate "SHA-1 digest algorithm (ARMv8 Crypto Extensions)"
-       depends on ARM64 && KERNEL_MODE_NEON
+       depends on ARM64 && KERNEL_MODE_NEON && !PREEMPT_RT_BASE
        select CRYPTO_HASH
 
 config CRYPTO_SHA2_ARM64_CE
        tristate "SHA-224/SHA-256 digest algorithm (ARMv8 Crypto Extensions)"
-       depends on ARM64 && KERNEL_MODE_NEON
+       depends on ARM64 && KERNEL_MODE_NEON && !PREEMPT_RT_BASE
        select CRYPTO_HASH
 
 config CRYPTO_GHASH_ARM64_CE
        tristate "GHASH (for GCM chaining mode) using ARMv8 Crypto Extensions"
-       depends on ARM64 && KERNEL_MODE_NEON
+       depends on ARM64 && KERNEL_MODE_NEON && !PREEMPT_RT_BASE
        select CRYPTO_HASH
 
 config CRYPTO_AES_ARM64_CE
        tristate "AES core cipher using ARMv8 Crypto Extensions"
-       depends on ARM64 && KERNEL_MODE_NEON
+       depends on ARM64 && KERNEL_MODE_NEON && !PREEMPT_RT_BASE
        select CRYPTO_ALGAPI
 
 config CRYPTO_AES_ARM64_CE_CCM
        tristate "AES in CCM mode using ARMv8 Crypto Extensions"
-       depends on ARM64 && KERNEL_MODE_NEON
+       depends on ARM64 && KERNEL_MODE_NEON && !PREEMPT_RT_BASE
        select CRYPTO_ALGAPI
        select CRYPTO_AES_ARM64_CE
        select CRYPTO_AEAD
 
 config CRYPTO_AES_ARM64_CE_BLK
        tristate "AES in ECB/CBC/CTR/XTS modes using ARMv8 Crypto Extensions"
-       depends on ARM64 && KERNEL_MODE_NEON
+       depends on ARM64 && KERNEL_MODE_NEON && !PREEMPT_RT_BASE
        select CRYPTO_BLKCIPHER
        select CRYPTO_AES_ARM64_CE
        select CRYPTO_ABLK_HELPER
 
 config CRYPTO_AES_ARM64_NEON_BLK
        tristate "AES in ECB/CBC/CTR/XTS modes using NEON instructions"
-       depends on ARM64 && KERNEL_MODE_NEON
+       depends on ARM64 && KERNEL_MODE_NEON && !PREEMPT_RT_BASE
        select CRYPTO_BLKCIPHER
        select CRYPTO_AES
        select CRYPTO_ABLK_HELPER
index a309f9f..b683284 100644 (file)
@@ -51,6 +51,7 @@ struct thread_info {
        u64                     ttbr0;          /* saved TTBR0_EL1 */
 #endif
        int                     preempt_count;  /* 0 => preemptable, <0 => bug */
+       int                     preempt_lazy_count; /* 0 => preemptable, <0 => bug */
 };
 
 #define INIT_THREAD_INFO(tsk)                                          \
@@ -85,6 +86,7 @@ struct thread_info {
 #define TIF_NEED_RESCHED       1
 #define TIF_NOTIFY_RESUME      2       /* callback before returning to user */
 #define TIF_FOREIGN_FPSTATE    3       /* CPU's FP state is not current's */
+#define TIF_NEED_RESCHED_LAZY  4
 #define TIF_NOHZ               7
 #define TIF_SYSCALL_TRACE      8
 #define TIF_SYSCALL_AUDIT      9
@@ -101,6 +103,7 @@ struct thread_info {
 #define _TIF_NEED_RESCHED      (1 << TIF_NEED_RESCHED)
 #define _TIF_NOTIFY_RESUME     (1 << TIF_NOTIFY_RESUME)
 #define _TIF_FOREIGN_FPSTATE   (1 << TIF_FOREIGN_FPSTATE)
+#define _TIF_NEED_RESCHED_LAZY (1 << TIF_NEED_RESCHED_LAZY)
 #define _TIF_NOHZ              (1 << TIF_NOHZ)
 #define _TIF_SYSCALL_TRACE     (1 << TIF_SYSCALL_TRACE)
 #define _TIF_SYSCALL_AUDIT     (1 << TIF_SYSCALL_AUDIT)
@@ -109,7 +112,9 @@ struct thread_info {
 #define _TIF_32BIT             (1 << TIF_32BIT)
 
 #define _TIF_WORK_MASK         (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \
-                                _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE)
+                                _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE | \
+                                _TIF_NEED_RESCHED_LAZY)
+#define _TIF_NEED_RESCHED_MASK (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY)
 
 #define _TIF_SYSCALL_WORK      (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
                                 _TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP | \
index b2debec..ae495cc 100644 (file)
@@ -39,6 +39,7 @@ int main(void)
   BLANK();
   DEFINE(TSK_TI_FLAGS,         offsetof(struct task_struct, thread_info.flags));
   DEFINE(TSK_TI_PREEMPT,       offsetof(struct task_struct, thread_info.preempt_count));
+  DEFINE(TSK_TI_PREEMPT_LAZY,  offsetof(struct task_struct, thread_info.preempt_lazy_count));
   DEFINE(TSK_TI_ADDR_LIMIT,    offsetof(struct task_struct, thread_info.addr_limit));
 #ifdef CONFIG_ARM64_SW_TTBR0_PAN
   DEFINE(TSK_TI_TTBR0,         offsetof(struct task_struct, thread_info.ttbr0));
index 3530d70..4f527de 100644 (file)
@@ -678,11 +678,16 @@ el1_irq:
 
 #ifdef CONFIG_PREEMPT
        ldr     w24, [tsk, #TSK_TI_PREEMPT]     // get preempt count
-       cbnz    w24, 1f                         // preempt count != 0
+       cbnz    w24, 2f                         // preempt count != 0
        ldr     x0, [tsk, #TSK_TI_FLAGS]        // get flags
-       tbz     x0, #TIF_NEED_RESCHED, 1f       // needs rescheduling?
-       bl      el1_preempt
+       tbnz    x0, #TIF_NEED_RESCHED, 1f       // needs rescheduling?
+
+       ldr     w24, [tsk, #TSK_TI_PREEMPT_LAZY] // get preempt lazy count
+       cbnz    w24, 2f                         // preempt lazy count != 0
+       tbz     x0, #TIF_NEED_RESCHED_LAZY, 2f  // needs rescheduling?
 1:
+       bl      el1_preempt
+2:
 #endif
 #ifdef CONFIG_TRACE_IRQFLAGS
        bl      trace_hardirqs_on
@@ -696,6 +701,7 @@ el1_preempt:
 1:     bl      preempt_schedule_irq            // irq en/disable is done inside
        ldr     x0, [tsk, #TSK_TI_FLAGS]        // get new tasks TI_FLAGS
        tbnz    x0, #TIF_NEED_RESCHED, 1b       // needs rescheduling?
+       tbnz    x0, #TIF_NEED_RESCHED_LAZY, 1b  // needs rescheduling?
        ret     x24
 #endif
 
index 404dd67..639dc6d 100644 (file)
@@ -409,7 +409,7 @@ asmlinkage void do_notify_resume(struct pt_regs *regs,
         */
        trace_hardirqs_off();
        do {
-               if (thread_flags & _TIF_NEED_RESCHED) {
+               if (thread_flags & _TIF_NEED_RESCHED_MASK) {
                        schedule();
                } else {
                        local_irq_enable();
index 24eb7fe..ef0a95d 100644 (file)
@@ -2520,7 +2520,7 @@ config MIPS_ASID_BITS_VARIABLE
 #
 config HIGHMEM
        bool "High Memory Support"
-       depends on 32BIT && CPU_SUPPORTS_HIGHMEM && SYS_SUPPORTS_HIGHMEM && !CPU_MIPS32_3_5_EVA
+       depends on 32BIT && CPU_SUPPORTS_HIGHMEM && SYS_SUPPORTS_HIGHMEM && !CPU_MIPS32_3_5_EVA && !PREEMPT_RT_FULL
 
 config CPU_SUPPORTS_HIGHMEM
        bool
index f529d3d..245c7ba 100644 (file)
@@ -52,10 +52,11 @@ config LOCKDEP_SUPPORT
 
 config RWSEM_GENERIC_SPINLOCK
        bool
+       default y if PREEMPT_RT_FULL
 
 config RWSEM_XCHGADD_ALGORITHM
        bool
-       default y
+       default y if !PREEMPT_RT_FULL
 
 config GENERIC_LOCKBREAK
        bool
@@ -136,6 +137,7 @@ config PPC
        select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
        select GENERIC_STRNCPY_FROM_USER
        select GENERIC_STRNLEN_USER
+       select HAVE_PREEMPT_LAZY
        select HAVE_MOD_ARCH_SPECIFIC
        select MODULES_USE_ELF_RELA
        select CLONE_BACKWARDS
@@ -328,7 +330,7 @@ menu "Kernel options"
 
 config HIGHMEM
        bool "High memory support"
-       depends on PPC32
+       depends on PPC32 && !PREEMPT_RT_FULL
 
 source kernel/Kconfig.hz
 source kernel/Kconfig.preempt
index 87e4b2d..981e501 100644 (file)
@@ -43,6 +43,8 @@ struct thread_info {
        int             cpu;                    /* cpu we're on */
        int             preempt_count;          /* 0 => preemptable,
                                                   <0 => BUG */
+       int             preempt_lazy_count;     /* 0 => preemptable,
+                                                  <0 => BUG */
        unsigned long   local_flags;            /* private flags for thread */
 #ifdef CONFIG_LIVEPATCH
        unsigned long *livepatch_sp;
@@ -88,8 +90,7 @@ static inline struct thread_info *current_thread_info(void)
 #define TIF_SYSCALL_TRACE      0       /* syscall trace active */
 #define TIF_SIGPENDING         1       /* signal pending */
 #define TIF_NEED_RESCHED       2       /* rescheduling necessary */
-#define TIF_POLLING_NRFLAG     3       /* true if poll_idle() is polling
-                                          TIF_NEED_RESCHED */
+#define TIF_NEED_RESCHED_LAZY  3       /* lazy rescheduling necessary */
 #define TIF_32BIT              4       /* 32 bit binary */
 #define TIF_RESTORE_TM         5       /* need to restore TM FP/VEC/VSX */
 #define TIF_SYSCALL_AUDIT      7       /* syscall auditing active */
@@ -107,6 +108,8 @@ static inline struct thread_info *current_thread_info(void)
 #if defined(CONFIG_PPC64)
 #define TIF_ELF2ABI            18      /* function descriptors must die! */
 #endif
+#define TIF_POLLING_NRFLAG     19      /* true if poll_idle() is polling
+                                          TIF_NEED_RESCHED */
 
 /* as above, but as bit values */
 #define _TIF_SYSCALL_TRACE     (1<<TIF_SYSCALL_TRACE)
@@ -125,14 +128,16 @@ static inline struct thread_info *current_thread_info(void)
 #define _TIF_SYSCALL_TRACEPOINT        (1<<TIF_SYSCALL_TRACEPOINT)
 #define _TIF_EMULATE_STACK_STORE       (1<<TIF_EMULATE_STACK_STORE)
 #define _TIF_NOHZ              (1<<TIF_NOHZ)
+#define _TIF_NEED_RESCHED_LAZY (1<<TIF_NEED_RESCHED_LAZY)
 #define _TIF_SYSCALL_DOTRACE   (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
                                 _TIF_SECCOMP | _TIF_SYSCALL_TRACEPOINT | \
                                 _TIF_NOHZ)
 
 #define _TIF_USER_WORK_MASK    (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
                                 _TIF_NOTIFY_RESUME | _TIF_UPROBE | \
-                                _TIF_RESTORE_TM)
+                                _TIF_RESTORE_TM | _TIF_NEED_RESCHED_LAZY)
 #define _TIF_PERSYSCALL_MASK   (_TIF_RESTOREALL|_TIF_NOERROR)
+#define _TIF_NEED_RESCHED_MASK (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY)
 
 /* Bits in local_flags */
 /* Don't move TLF_NAPPING without adjusting the code in entry_32.S */
index dfcf28b..40f047d 100644 (file)
@@ -156,6 +156,7 @@ int main(void)
        DEFINE(TI_FLAGS, offsetof(struct thread_info, flags));
        DEFINE(TI_LOCAL_FLAGS, offsetof(struct thread_info, local_flags));
        DEFINE(TI_PREEMPT, offsetof(struct thread_info, preempt_count));
+       DEFINE(TI_PREEMPT_LAZY, offsetof(struct thread_info, preempt_lazy_count));
        DEFINE(TI_TASK, offsetof(struct thread_info, task));
        DEFINE(TI_CPU, offsetof(struct thread_info, cpu));
 
index bdd88f9..3a30180 100644 (file)
@@ -848,7 +848,14 @@ resume_kernel:
        cmpwi   0,r0,0          /* if non-zero, just restore regs and return */
        bne     restore
        andi.   r8,r8,_TIF_NEED_RESCHED
+       bne+    1f
+       lwz     r0,TI_PREEMPT_LAZY(r9)
+       cmpwi   0,r0,0          /* if non-zero, just restore regs and return */
+       bne     restore
+       lwz     r0,TI_FLAGS(r9)
+       andi.   r0,r0,_TIF_NEED_RESCHED_LAZY
        beq+    restore
+1:
        lwz     r3,_MSR(r1)
        andi.   r0,r3,MSR_EE    /* interrupts off? */
        beq     restore         /* don't schedule if so */
@@ -859,11 +866,11 @@ resume_kernel:
         */
        bl      trace_hardirqs_off
 #endif
-1:     bl      preempt_schedule_irq
+2:     bl      preempt_schedule_irq
        CURRENT_THREAD_INFO(r9, r1)
        lwz     r3,TI_FLAGS(r9)
-       andi.   r0,r3,_TIF_NEED_RESCHED
-       bne-    1b
+       andi.   r0,r3,_TIF_NEED_RESCHED_MASK
+       bne-    2b
 #ifdef CONFIG_TRACE_IRQFLAGS
        /* And now, to properly rebalance the above, we tell lockdep they
         * are being turned back on, which will happen when we return
@@ -1190,7 +1197,7 @@ global_dbcr0:
 #endif /* !(CONFIG_4xx || CONFIG_BOOKE) */
 
 do_work:                       /* r10 contains MSR_KERNEL here */
-       andi.   r0,r9,_TIF_NEED_RESCHED
+       andi.   r0,r9,_TIF_NEED_RESCHED_MASK
        beq     do_user_signal
 
 do_resched:                    /* r10 contains MSR_KERNEL here */
@@ -1211,7 +1218,7 @@ recheck:
        MTMSRD(r10)             /* disable interrupts */
        CURRENT_THREAD_INFO(r9, r1)
        lwz     r9,TI_FLAGS(r9)
-       andi.   r0,r9,_TIF_NEED_RESCHED
+       andi.   r0,r9,_TIF_NEED_RESCHED_MASK
        bne-    do_resched
        andi.   r0,r9,_TIF_USER_WORK_MASK
        beq     restore_user
index 38f0a75..d84a974 100644 (file)
@@ -746,7 +746,7 @@ _GLOBAL(ret_from_except_lite)
        bl      restore_math
        b       restore
 #endif
-1:     andi.   r0,r4,_TIF_NEED_RESCHED
+1:     andi.   r0,r4,_TIF_NEED_RESCHED_MASK
        beq     2f
        bl      restore_interrupts
        SCHEDULE_USER
@@ -808,10 +808,18 @@ resume_kernel:
 
 #ifdef CONFIG_PREEMPT
        /* Check if we need to preempt */
+       lwz     r8,TI_PREEMPT(r9)
+       cmpwi   0,r8,0          /* if non-zero, just restore regs and return */
+       bne     restore
        andi.   r0,r4,_TIF_NEED_RESCHED
+       bne+    check_count
+
+       andi.   r0,r4,_TIF_NEED_RESCHED_LAZY
        beq+    restore
+       lwz     r8,TI_PREEMPT_LAZY(r9)
+
        /* Check that preempt_count() == 0 and interrupts are enabled */
-       lwz     r8,TI_PREEMPT(r9)
+check_count:
        cmpwi   cr1,r8,0
        ld      r0,SOFTE(r1)
        cmpdi   r0,0
@@ -828,7 +836,7 @@ resume_kernel:
        /* Re-test flags and eventually loop */
        CURRENT_THREAD_INFO(r9, r1)
        ld      r4,TI_FLAGS(r9)
-       andi.   r0,r4,_TIF_NEED_RESCHED
+       andi.   r0,r4,_TIF_NEED_RESCHED_MASK
        bne     1b
 
        /*
index eff4a33..cab3e4f 100644 (file)
@@ -659,6 +659,7 @@ void irq_ctx_init(void)
        }
 }
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 void do_softirq_own_stack(void)
 {
        struct thread_info *curtp, *irqtp;
@@ -676,6 +677,7 @@ void do_softirq_own_stack(void)
        if (irqtp->flags)
                set_bits(irqtp->flags, &curtp->flags);
 }
+#endif
 
 irq_hw_number_t virq_to_hw(unsigned int virq)
 {
index 030d72d..b471a70 100644 (file)
@@ -41,6 +41,7 @@
  * We store the saved ksp_limit in the unused part
  * of the STACK_FRAME_OVERHEAD
  */
+#ifndef CONFIG_PREEMPT_RT_FULL
 _GLOBAL(call_do_softirq)
        mflr    r0
        stw     r0,4(r1)
@@ -57,6 +58,7 @@ _GLOBAL(call_do_softirq)
        stw     r10,THREAD+KSP_LIMIT(r2)
        mtlr    r0
        blr
+#endif
 
 /*
  * void call_do_irq(struct pt_regs *regs, struct thread_info *irqtp);
index 4cefe68..cb2ee4b 100644 (file)
@@ -31,6 +31,7 @@
 
        .text
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 _GLOBAL(call_do_softirq)
        mflr    r0
        std     r0,16(r1)
@@ -41,6 +42,7 @@ _GLOBAL(call_do_softirq)
        ld      r0,16(r1)
        mtlr    r0
        blr
+#endif
 
 _GLOBAL(call_do_irq)
        mflr    r0
index 029be26..9528089 100644 (file)
@@ -175,6 +175,7 @@ config KVM_E500MC
 config KVM_MPIC
        bool "KVM in-kernel MPIC emulation"
        depends on KVM && E500
+       depends on !PREEMPT_RT_FULL
        select HAVE_KVM_IRQCHIP
        select HAVE_KVM_IRQFD
        select HAVE_KVM_IRQ_ROUTING
index e484624..2670cee 100644 (file)
@@ -752,7 +752,7 @@ static int ps3_notification_read_write(struct ps3_notification_device *dev,
        }
        pr_debug("%s:%u: notification %s issued\n", __func__, __LINE__, op);
 
-       res = wait_event_interruptible(dev->done.wait,
+       res = swait_event_interruptible(dev->done.wait,
                                       dev->done.done || kthread_should_stop());
        if (kthread_should_stop())
                res = -EINTR;
index 6c0378c..abd58b4 100644 (file)
@@ -147,6 +147,7 @@ void irq_ctx_exit(int cpu)
        hardirq_ctx[cpu] = NULL;
 }
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 void do_softirq_own_stack(void)
 {
        struct thread_info *curctx;
@@ -174,6 +175,7 @@ void do_softirq_own_stack(void)
                  "r5", "r6", "r7", "r8", "r9", "r15", "t", "pr"
        );
 }
+#endif
 #else
 static inline void handle_one_irq(unsigned int irq)
 {
index cef42d4..38f51d5 100644 (file)
@@ -194,12 +194,10 @@ config NR_CPUS
 source kernel/Kconfig.hz
 
 config RWSEM_GENERIC_SPINLOCK
-       bool
-       default y if SPARC32
+       def_bool PREEMPT_RT_FULL
 
 config RWSEM_XCHGADD_ALGORITHM
-       bool
-       default y if SPARC64
+       def_bool !RWSEM_GENERIC_SPINLOCK && !PREEMPT_RT_FULL
 
 config GENERIC_HWEIGHT
        bool
index 5cbf03c..6067d93 100644 (file)
@@ -854,6 +854,7 @@ void __irq_entry handler_irq(int pil, struct pt_regs *regs)
        set_irq_regs(old_regs);
 }
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 void do_softirq_own_stack(void)
 {
        void *orig_sp, *sp = softirq_stack[smp_processor_id()];
@@ -868,6 +869,7 @@ void do_softirq_own_stack(void)
        __asm__ __volatile__("mov %0, %%sp"
                             : : "r" (orig_sp));
 }
+#endif
 
 #ifdef CONFIG_HOTPLUG_CPU
 void fixup_irqs(void)
index 80636ca..aed71b6 100644 (file)
@@ -17,6 +17,7 @@ config X86_64
 ### Arch settings
 config X86
        def_bool y
+       select HAVE_PREEMPT_LAZY
        select ACPI_LEGACY_TABLES_LOOKUP        if ACPI
        select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
        select ANON_INODES
@@ -234,8 +235,11 @@ config ARCH_MAY_HAVE_PC_FDC
        def_bool y
        depends on ISA_DMA_API
 
+config RWSEM_GENERIC_SPINLOCK
+       def_bool PREEMPT_RT_FULL
+
 config RWSEM_XCHGADD_ALGORITHM
-       def_bool y
+       def_bool !RWSEM_GENERIC_SPINLOCK && !PREEMPT_RT_FULL
 
 config GENERIC_CALIBRATE_DELAY
        def_bool y
@@ -912,7 +916,7 @@ config IOMMU_HELPER
 config MAXSMP
        bool "Enable Maximum number of SMP Processors and NUMA Nodes"
        depends on X86_64 && SMP && DEBUG_KERNEL
-       select CPUMASK_OFFSTACK
+       select CPUMASK_OFFSTACK if !PREEMPT_RT_FULL
        ---help---
          Enable maximum number of CPUS and NUMA Nodes for this architecture.
          If unsure, say N.
index d9ae404..0f1d62d 100644 (file)
@@ -372,14 +372,14 @@ static int ecb_encrypt(struct blkcipher_desc *desc,
        err = blkcipher_walk_virt(desc, &walk);
        desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
 
-       kernel_fpu_begin();
        while ((nbytes = walk.nbytes)) {
+               kernel_fpu_begin();
                aesni_ecb_enc(ctx, walk.dst.virt.addr, walk.src.virt.addr,
-                             nbytes & AES_BLOCK_MASK);
+                               nbytes & AES_BLOCK_MASK);
+               kernel_fpu_end();
                nbytes &= AES_BLOCK_SIZE - 1;
                err = blkcipher_walk_done(desc, &walk, nbytes);
        }
-       kernel_fpu_end();
 
        return err;
 }
@@ -396,14 +396,14 @@ static int ecb_decrypt(struct blkcipher_desc *desc,
        err = blkcipher_walk_virt(desc, &walk);
        desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
 
-       kernel_fpu_begin();
        while ((nbytes = walk.nbytes)) {
+               kernel_fpu_begin();
                aesni_ecb_dec(ctx, walk.dst.virt.addr, walk.src.virt.addr,
                              nbytes & AES_BLOCK_MASK);
+               kernel_fpu_end();
                nbytes &= AES_BLOCK_SIZE - 1;
                err = blkcipher_walk_done(desc, &walk, nbytes);
        }
-       kernel_fpu_end();
 
        return err;
 }
@@ -420,14 +420,14 @@ static int cbc_encrypt(struct blkcipher_desc *desc,
        err = blkcipher_walk_virt(desc, &walk);
        desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
 
-       kernel_fpu_begin();
        while ((nbytes = walk.nbytes)) {
+               kernel_fpu_begin();
                aesni_cbc_enc(ctx, walk.dst.virt.addr, walk.src.virt.addr,
                              nbytes & AES_BLOCK_MASK, walk.iv);
+               kernel_fpu_end();
                nbytes &= AES_BLOCK_SIZE - 1;
                err = blkcipher_walk_done(desc, &walk, nbytes);
        }
-       kernel_fpu_end();
 
        return err;
 }
@@ -444,14 +444,14 @@ static int cbc_decrypt(struct blkcipher_desc *desc,
        err = blkcipher_walk_virt(desc, &walk);
        desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
 
-       kernel_fpu_begin();
        while ((nbytes = walk.nbytes)) {
+               kernel_fpu_begin();
                aesni_cbc_dec(ctx, walk.dst.virt.addr, walk.src.virt.addr,
                              nbytes & AES_BLOCK_MASK, walk.iv);
+               kernel_fpu_end();
                nbytes &= AES_BLOCK_SIZE - 1;
                err = blkcipher_walk_done(desc, &walk, nbytes);
        }
-       kernel_fpu_end();
 
        return err;
 }
@@ -503,18 +503,20 @@ static int ctr_crypt(struct blkcipher_desc *desc,
        err = blkcipher_walk_virt_block(desc, &walk, AES_BLOCK_SIZE);
        desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
 
-       kernel_fpu_begin();
        while ((nbytes = walk.nbytes) >= AES_BLOCK_SIZE) {
+               kernel_fpu_begin();
                aesni_ctr_enc_tfm(ctx, walk.dst.virt.addr, walk.src.virt.addr,
                                      nbytes & AES_BLOCK_MASK, walk.iv);
+               kernel_fpu_end();
                nbytes &= AES_BLOCK_SIZE - 1;
                err = blkcipher_walk_done(desc, &walk, nbytes);
        }
        if (walk.nbytes) {
+               kernel_fpu_begin();
                ctr_crypt_final(ctx, &walk);
+               kernel_fpu_end();
                err = blkcipher_walk_done(desc, &walk, 0);
        }
-       kernel_fpu_end();
 
        return err;
 }
index 60907c1..0902db7 100644 (file)
@@ -206,6 +206,20 @@ struct crypt_priv {
        bool fpu_enabled;
 };
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+static void camellia_fpu_end_rt(struct crypt_priv *ctx)
+{
+       bool fpu_enabled = ctx->fpu_enabled;
+
+       if (!fpu_enabled)
+               return;
+       camellia_fpu_end(fpu_enabled);
+       ctx->fpu_enabled = false;
+}
+#else
+static void camellia_fpu_end_rt(struct crypt_priv *ctx) { }
+#endif
+
 static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
 {
        const unsigned int bsize = CAMELLIA_BLOCK_SIZE;
@@ -221,16 +235,19 @@ static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
        }
 
        if (nbytes >= CAMELLIA_AESNI_PARALLEL_BLOCKS * bsize) {
+               kernel_fpu_resched();
                camellia_ecb_enc_16way(ctx->ctx, srcdst, srcdst);
                srcdst += bsize * CAMELLIA_AESNI_PARALLEL_BLOCKS;
                nbytes -= bsize * CAMELLIA_AESNI_PARALLEL_BLOCKS;
        }
 
        while (nbytes >= CAMELLIA_PARALLEL_BLOCKS * bsize) {
+               kernel_fpu_resched();
                camellia_enc_blk_2way(ctx->ctx, srcdst, srcdst);
                srcdst += bsize * CAMELLIA_PARALLEL_BLOCKS;
                nbytes -= bsize * CAMELLIA_PARALLEL_BLOCKS;
        }
+       camellia_fpu_end_rt(ctx);
 
        for (i = 0; i < nbytes / bsize; i++, srcdst += bsize)
                camellia_enc_blk(ctx->ctx, srcdst, srcdst);
@@ -251,16 +268,19 @@ static void decrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
        }
 
        if (nbytes >= CAMELLIA_AESNI_PARALLEL_BLOCKS * bsize) {
+               kernel_fpu_resched();
                camellia_ecb_dec_16way(ctx->ctx, srcdst, srcdst);
                srcdst += bsize * CAMELLIA_AESNI_PARALLEL_BLOCKS;
                nbytes -= bsize * CAMELLIA_AESNI_PARALLEL_BLOCKS;
        }
 
        while (nbytes >= CAMELLIA_PARALLEL_BLOCKS * bsize) {
+               kernel_fpu_resched();
                camellia_dec_blk_2way(ctx->ctx, srcdst, srcdst);
                srcdst += bsize * CAMELLIA_PARALLEL_BLOCKS;
                nbytes -= bsize * CAMELLIA_PARALLEL_BLOCKS;
        }
+       camellia_fpu_end_rt(ctx);
 
        for (i = 0; i < nbytes / bsize; i++, srcdst += bsize)
                camellia_dec_blk(ctx->ctx, srcdst, srcdst);
index d96429d..3b8e918 100644 (file)
@@ -210,6 +210,21 @@ struct crypt_priv {
        bool fpu_enabled;
 };
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+static void camellia_fpu_end_rt(struct crypt_priv *ctx)
+{
+       bool fpu_enabled = ctx->fpu_enabled;
+
+       if (!fpu_enabled)
+               return;
+       camellia_fpu_end(fpu_enabled);
+       ctx->fpu_enabled = false;
+}
+
+#else
+static void camellia_fpu_end_rt(struct crypt_priv *ctx) { }
+#endif
+
 static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
 {
        const unsigned int bsize = CAMELLIA_BLOCK_SIZE;
@@ -225,10 +240,12 @@ static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
        }
 
        while (nbytes >= CAMELLIA_PARALLEL_BLOCKS * bsize) {
+               kernel_fpu_resched();
                camellia_enc_blk_2way(ctx->ctx, srcdst, srcdst);
                srcdst += bsize * CAMELLIA_PARALLEL_BLOCKS;
                nbytes -= bsize * CAMELLIA_PARALLEL_BLOCKS;
        }
+       camellia_fpu_end_rt(ctx);
 
        for (i = 0; i < nbytes / bsize; i++, srcdst += bsize)
                camellia_enc_blk(ctx->ctx, srcdst, srcdst);
@@ -249,10 +266,12 @@ static void decrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
        }
 
        while (nbytes >= CAMELLIA_PARALLEL_BLOCKS * bsize) {
+               kernel_fpu_resched();
                camellia_dec_blk_2way(ctx->ctx, srcdst, srcdst);
                srcdst += bsize * CAMELLIA_PARALLEL_BLOCKS;
                nbytes -= bsize * CAMELLIA_PARALLEL_BLOCKS;
        }
+       camellia_fpu_end_rt(ctx);
 
        for (i = 0; i < nbytes / bsize; i++, srcdst += bsize)
                camellia_dec_blk(ctx->ctx, srcdst, srcdst);
index f8fe11d..1e546e3 100644 (file)
@@ -59,7 +59,7 @@ static inline void cast5_fpu_end(bool fpu_enabled)
 static int ecb_crypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk,
                     bool enc)
 {
-       bool fpu_enabled = false;
+       bool fpu_enabled;
        struct cast5_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
        const unsigned int bsize = CAST5_BLOCK_SIZE;
        unsigned int nbytes;
@@ -73,7 +73,7 @@ static int ecb_crypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk,
                u8 *wsrc = walk->src.virt.addr;
                u8 *wdst = walk->dst.virt.addr;
 
-               fpu_enabled = cast5_fpu_begin(fpu_enabled, nbytes);
+               fpu_enabled = cast5_fpu_begin(false, nbytes);
 
                /* Process multi-block batch */
                if (nbytes >= bsize * CAST5_PARALLEL_BLOCKS) {
@@ -102,10 +102,9 @@ static int ecb_crypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk,
                } while (nbytes >= bsize);
 
 done:
+               cast5_fpu_end(fpu_enabled);
                err = blkcipher_walk_done(desc, walk, nbytes);
        }
-
-       cast5_fpu_end(fpu_enabled);
        return err;
 }
 
@@ -226,7 +225,7 @@ done:
 static int cbc_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
                       struct scatterlist *src, unsigned int nbytes)
 {
-       bool fpu_enabled = false;
+       bool fpu_enabled;
        struct blkcipher_walk walk;
        int err;
 
@@ -235,12 +234,11 @@ static int cbc_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
        desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
 
        while ((nbytes = walk.nbytes)) {
-               fpu_enabled = cast5_fpu_begin(fpu_enabled, nbytes);
+               fpu_enabled = cast5_fpu_begin(false, nbytes);
                nbytes = __cbc_decrypt(desc, &walk);
+               cast5_fpu_end(fpu_enabled);
                err = blkcipher_walk_done(desc, &walk, nbytes);
        }
-
-       cast5_fpu_end(fpu_enabled);
        return err;
 }
 
@@ -310,7 +308,7 @@ done:
 static int ctr_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
                     struct scatterlist *src, unsigned int nbytes)
 {
-       bool fpu_enabled = false;
+       bool fpu_enabled;
        struct blkcipher_walk walk;
        int err;
 
@@ -319,13 +317,12 @@ static int ctr_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
        desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
 
        while ((nbytes = walk.nbytes) >= CAST5_BLOCK_SIZE) {
-               fpu_enabled = cast5_fpu_begin(fpu_enabled, nbytes);
+               fpu_enabled = cast5_fpu_begin(false, nbytes);
                nbytes = __ctr_crypt(desc, &walk);
+               cast5_fpu_end(fpu_enabled);
                err = blkcipher_walk_done(desc, &walk, nbytes);
        }
 
-       cast5_fpu_end(fpu_enabled);
-
        if (walk.nbytes) {
                ctr_crypt_final(desc, &walk);
                err = blkcipher_walk_done(desc, &walk, 0);
index 50e6847..8caf9ba 100644 (file)
@@ -205,19 +205,33 @@ struct crypt_priv {
        bool fpu_enabled;
 };
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+static void cast6_fpu_end_rt(struct crypt_priv *ctx)
+{
+       bool fpu_enabled = ctx->fpu_enabled;
+
+       if (!fpu_enabled)
+               return;
+       cast6_fpu_end(fpu_enabled);
+       ctx->fpu_enabled = false;
+}
+
+#else
+static void cast6_fpu_end_rt(struct crypt_priv *ctx) { }
+#endif
+
 static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
 {
        const unsigned int bsize = CAST6_BLOCK_SIZE;
        struct crypt_priv *ctx = priv;
        int i;
 
-       ctx->fpu_enabled = cast6_fpu_begin(ctx->fpu_enabled, nbytes);
-
        if (nbytes == bsize * CAST6_PARALLEL_BLOCKS) {
+               ctx->fpu_enabled = cast6_fpu_begin(ctx->fpu_enabled, nbytes);
                cast6_ecb_enc_8way(ctx->ctx, srcdst, srcdst);
+               cast6_fpu_end_rt(ctx);
                return;
        }
-
        for (i = 0; i < nbytes / bsize; i++, srcdst += bsize)
                __cast6_encrypt(ctx->ctx, srcdst, srcdst);
 }
@@ -228,10 +242,10 @@ static void decrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
        struct crypt_priv *ctx = priv;
        int i;
 
-       ctx->fpu_enabled = cast6_fpu_begin(ctx->fpu_enabled, nbytes);
-
        if (nbytes == bsize * CAST6_PARALLEL_BLOCKS) {
+               ctx->fpu_enabled = cast6_fpu_begin(ctx->fpu_enabled, nbytes);
                cast6_ecb_dec_8way(ctx->ctx, srcdst, srcdst);
+               cast6_fpu_end_rt(ctx);
                return;
        }
 
index 0a5fedf..15dee15 100644 (file)
@@ -81,23 +81,24 @@ static int chacha20_simd(struct blkcipher_desc *desc, struct scatterlist *dst,
 
        crypto_chacha20_init(state, crypto_blkcipher_ctx(desc->tfm), walk.iv);
 
-       kernel_fpu_begin();
-
        while (walk.nbytes >= CHACHA20_BLOCK_SIZE) {
+               kernel_fpu_begin();
+
                chacha20_dosimd(state, walk.dst.virt.addr, walk.src.virt.addr,
                                rounddown(walk.nbytes, CHACHA20_BLOCK_SIZE));
+               kernel_fpu_end();
                err = blkcipher_walk_done(desc, &walk,
                                          walk.nbytes % CHACHA20_BLOCK_SIZE);
        }
 
        if (walk.nbytes) {
+               kernel_fpu_begin();
                chacha20_dosimd(state, walk.dst.virt.addr, walk.src.virt.addr,
                                walk.nbytes);
+               kernel_fpu_end();
                err = blkcipher_walk_done(desc, &walk, 0);
        }
 
-       kernel_fpu_end();
-
        return err;
 }
 
index 6a85598..3a506ce 100644 (file)
@@ -39,7 +39,7 @@ static int __glue_ecb_crypt_128bit(const struct common_glue_ctx *gctx,
        void *ctx = crypto_blkcipher_ctx(desc->tfm);
        const unsigned int bsize = 128 / 8;
        unsigned int nbytes, i, func_bytes;
-       bool fpu_enabled = false;
+       bool fpu_enabled;
        int err;
 
        err = blkcipher_walk_virt(desc, walk);
@@ -49,7 +49,7 @@ static int __glue_ecb_crypt_128bit(const struct common_glue_ctx *gctx,
                u8 *wdst = walk->dst.virt.addr;
 
                fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
-                                            desc, fpu_enabled, nbytes);
+                                            desc, false, nbytes);
 
                for (i = 0; i < gctx->num_funcs; i++) {
                        func_bytes = bsize * gctx->funcs[i].num_blocks;
@@ -71,10 +71,10 @@ static int __glue_ecb_crypt_128bit(const struct common_glue_ctx *gctx,
                }
 
 done:
+               glue_fpu_end(fpu_enabled);
                err = blkcipher_walk_done(desc, walk, nbytes);
        }
 
-       glue_fpu_end(fpu_enabled);
        return err;
 }
 
@@ -194,7 +194,7 @@ int glue_cbc_decrypt_128bit(const struct common_glue_ctx *gctx,
                            struct scatterlist *src, unsigned int nbytes)
 {
        const unsigned int bsize = 128 / 8;
-       bool fpu_enabled = false;
+       bool fpu_enabled;
        struct blkcipher_walk walk;
        int err;
 
@@ -203,12 +203,12 @@ int glue_cbc_decrypt_128bit(const struct common_glue_ctx *gctx,
 
        while ((nbytes = walk.nbytes)) {
                fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
-                                            desc, fpu_enabled, nbytes);
+                                            desc, false, nbytes);
                nbytes = __glue_cbc_decrypt_128bit(gctx, desc, &walk);
+               glue_fpu_end(fpu_enabled);
                err = blkcipher_walk_done(desc, &walk, nbytes);
        }
 
-       glue_fpu_end(fpu_enabled);
        return err;
 }
 EXPORT_SYMBOL_GPL(glue_cbc_decrypt_128bit);
@@ -277,7 +277,7 @@ int glue_ctr_crypt_128bit(const struct common_glue_ctx *gctx,
                          struct scatterlist *src, unsigned int nbytes)
 {
        const unsigned int bsize = 128 / 8;
-       bool fpu_enabled = false;
+       bool fpu_enabled;
        struct blkcipher_walk walk;
        int err;
 
@@ -286,13 +286,12 @@ int glue_ctr_crypt_128bit(const struct common_glue_ctx *gctx,
 
        while ((nbytes = walk.nbytes) >= bsize) {
                fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
-                                            desc, fpu_enabled, nbytes);
+                                            desc, false, nbytes);
                nbytes = __glue_ctr_crypt_128bit(gctx, desc, &walk);
+               glue_fpu_end(fpu_enabled);
                err = blkcipher_walk_done(desc, &walk, nbytes);
        }
 
-       glue_fpu_end(fpu_enabled);
-
        if (walk.nbytes) {
                glue_ctr_crypt_final_128bit(
                        gctx->funcs[gctx->num_funcs - 1].fn_u.ctr, desc, &walk);
@@ -347,7 +346,7 @@ int glue_xts_crypt_128bit(const struct common_glue_ctx *gctx,
                          void *tweak_ctx, void *crypt_ctx)
 {
        const unsigned int bsize = 128 / 8;
-       bool fpu_enabled = false;
+       bool fpu_enabled;
        struct blkcipher_walk walk;
        int err;
 
@@ -360,21 +359,21 @@ int glue_xts_crypt_128bit(const struct common_glue_ctx *gctx,
 
        /* set minimum length to bsize, for tweak_fn */
        fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
-                                    desc, fpu_enabled,
+                                    desc, false,
                                     nbytes < bsize ? bsize : nbytes);
-
        /* calculate first value of T */
        tweak_fn(tweak_ctx, walk.iv, walk.iv);
+       glue_fpu_end(fpu_enabled);
 
        while (nbytes) {
+               fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
+                               desc, false, nbytes);
                nbytes = __glue_xts_crypt_128bit(gctx, crypt_ctx, desc, &walk);
 
+               glue_fpu_end(fpu_enabled);
                err = blkcipher_walk_done(desc, &walk, nbytes);
                nbytes = walk.nbytes;
        }
-
-       glue_fpu_end(fpu_enabled);
-
        return err;
 }
 EXPORT_SYMBOL_GPL(glue_xts_crypt_128bit);
index 870f6d8..5c806bf 100644 (file)
@@ -184,6 +184,21 @@ struct crypt_priv {
        bool fpu_enabled;
 };
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+static void serpent_fpu_end_rt(struct crypt_priv *ctx)
+{
+       bool fpu_enabled = ctx->fpu_enabled;
+
+       if (!fpu_enabled)
+               return;
+       serpent_fpu_end(fpu_enabled);
+       ctx->fpu_enabled = false;
+}
+
+#else
+static void serpent_fpu_end_rt(struct crypt_priv *ctx) { }
+#endif
+
 static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
 {
        const unsigned int bsize = SERPENT_BLOCK_SIZE;
@@ -199,10 +214,12 @@ static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
        }
 
        while (nbytes >= SERPENT_PARALLEL_BLOCKS * bsize) {
+               kernel_fpu_resched();
                serpent_ecb_enc_8way_avx(ctx->ctx, srcdst, srcdst);
                srcdst += bsize * SERPENT_PARALLEL_BLOCKS;
                nbytes -= bsize * SERPENT_PARALLEL_BLOCKS;
        }
+       serpent_fpu_end_rt(ctx);
 
        for (i = 0; i < nbytes / bsize; i++, srcdst += bsize)
                __serpent_encrypt(ctx->ctx, srcdst, srcdst);
@@ -223,10 +240,12 @@ static void decrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
        }
 
        while (nbytes >= SERPENT_PARALLEL_BLOCKS * bsize) {
+               kernel_fpu_resched();
                serpent_ecb_dec_8way_avx(ctx->ctx, srcdst, srcdst);
                srcdst += bsize * SERPENT_PARALLEL_BLOCKS;
                nbytes -= bsize * SERPENT_PARALLEL_BLOCKS;
        }
+       serpent_fpu_end_rt(ctx);
 
        for (i = 0; i < nbytes / bsize; i++, srcdst += bsize)
                __serpent_decrypt(ctx->ctx, srcdst, srcdst);
index 6f778d3..46dcbdb 100644 (file)
@@ -218,16 +218,31 @@ struct crypt_priv {
        bool fpu_enabled;
 };
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+static void serpent_fpu_end_rt(struct crypt_priv *ctx)
+{
+       bool fpu_enabled = ctx->fpu_enabled;
+
+       if (!fpu_enabled)
+               return;
+       serpent_fpu_end(fpu_enabled);
+       ctx->fpu_enabled = false;
+}
+
+#else
+static void serpent_fpu_end_rt(struct crypt_priv *ctx) { }
+#endif
+
 static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
 {
        const unsigned int bsize = SERPENT_BLOCK_SIZE;
        struct crypt_priv *ctx = priv;
        int i;
 
-       ctx->fpu_enabled = serpent_fpu_begin(ctx->fpu_enabled, nbytes);
-
        if (nbytes == bsize * SERPENT_PARALLEL_BLOCKS) {
+               ctx->fpu_enabled = serpent_fpu_begin(ctx->fpu_enabled, nbytes);
                serpent_ecb_enc_8way_avx(ctx->ctx, srcdst, srcdst);
+               serpent_fpu_end_rt(ctx);
                return;
        }
 
@@ -241,10 +256,10 @@ static void decrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
        struct crypt_priv *ctx = priv;
        int i;
 
-       ctx->fpu_enabled = serpent_fpu_begin(ctx->fpu_enabled, nbytes);
-
        if (nbytes == bsize * SERPENT_PARALLEL_BLOCKS) {
+               ctx->fpu_enabled = serpent_fpu_begin(ctx->fpu_enabled, nbytes);
                serpent_ecb_dec_8way_avx(ctx->ctx, srcdst, srcdst);
+               serpent_fpu_end_rt(ctx);
                return;
        }
 
index 644f97a..7b135b4 100644 (file)
@@ -187,16 +187,31 @@ struct crypt_priv {
        bool fpu_enabled;
 };
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+static void serpent_fpu_end_rt(struct crypt_priv *ctx)
+{
+       bool fpu_enabled = ctx->fpu_enabled;
+
+       if (!fpu_enabled)
+               return;
+       serpent_fpu_end(fpu_enabled);
+       ctx->fpu_enabled = false;
+}
+
+#else
+static void serpent_fpu_end_rt(struct crypt_priv *ctx) { }
+#endif
+
 static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
 {
        const unsigned int bsize = SERPENT_BLOCK_SIZE;
        struct crypt_priv *ctx = priv;
        int i;
 
-       ctx->fpu_enabled = serpent_fpu_begin(ctx->fpu_enabled, nbytes);
-
        if (nbytes == bsize * SERPENT_PARALLEL_BLOCKS) {
+               ctx->fpu_enabled = serpent_fpu_begin(ctx->fpu_enabled, nbytes);
                serpent_enc_blk_xway(ctx->ctx, srcdst, srcdst);
+               serpent_fpu_end_rt(ctx);
                return;
        }
 
@@ -210,10 +225,10 @@ static void decrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
        struct crypt_priv *ctx = priv;
        int i;
 
-       ctx->fpu_enabled = serpent_fpu_begin(ctx->fpu_enabled, nbytes);
-
        if (nbytes == bsize * SERPENT_PARALLEL_BLOCKS) {
+               ctx->fpu_enabled = serpent_fpu_begin(ctx->fpu_enabled, nbytes);
                serpent_dec_blk_xway(ctx->ctx, srcdst, srcdst);
+               serpent_fpu_end_rt(ctx);
                return;
        }
 
index b7a3904..de00fe2 100644 (file)
@@ -218,6 +218,21 @@ struct crypt_priv {
        bool fpu_enabled;
 };
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+static void twofish_fpu_end_rt(struct crypt_priv *ctx)
+{
+       bool fpu_enabled = ctx->fpu_enabled;
+
+       if (!fpu_enabled)
+               return;
+       twofish_fpu_end(fpu_enabled);
+       ctx->fpu_enabled = false;
+}
+
+#else
+static void twofish_fpu_end_rt(struct crypt_priv *ctx) { }
+#endif
+
 static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
 {
        const unsigned int bsize = TF_BLOCK_SIZE;
@@ -228,12 +243,16 @@ static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
 
        if (nbytes == bsize * TWOFISH_PARALLEL_BLOCKS) {
                twofish_ecb_enc_8way(ctx->ctx, srcdst, srcdst);
+               twofish_fpu_end_rt(ctx);
                return;
        }
 
-       for (i = 0; i < nbytes / (bsize * 3); i++, srcdst += bsize * 3)
+       for (i = 0; i < nbytes / (bsize * 3); i++, srcdst += bsize * 3) {
+               kernel_fpu_resched();
                twofish_enc_blk_3way(ctx->ctx, srcdst, srcdst);
+       }
 
+       twofish_fpu_end_rt(ctx);
        nbytes %= bsize * 3;
 
        for (i = 0; i < nbytes / bsize; i++, srcdst += bsize)
@@ -250,11 +269,15 @@ static void decrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
 
        if (nbytes == bsize * TWOFISH_PARALLEL_BLOCKS) {
                twofish_ecb_dec_8way(ctx->ctx, srcdst, srcdst);
+               twofish_fpu_end_rt(ctx);
                return;
        }
 
-       for (i = 0; i < nbytes / (bsize * 3); i++, srcdst += bsize * 3)
+       for (i = 0; i < nbytes / (bsize * 3); i++, srcdst += bsize * 3) {
+               kernel_fpu_resched();
                twofish_dec_blk_3way(ctx->ctx, srcdst, srcdst);
+       }
+       twofish_fpu_end_rt(ctx);
 
        nbytes %= bsize * 3;
 
index 8841d01..ded0ae2 100644 (file)
@@ -131,7 +131,7 @@ static long syscall_trace_enter(struct pt_regs *regs)
 
 #define EXIT_TO_USERMODE_LOOP_FLAGS                            \
        (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_UPROBE |   \
-        _TIF_NEED_RESCHED | _TIF_USER_RETURN_NOTIFY)
+        _TIF_NEED_RESCHED_MASK | _TIF_USER_RETURN_NOTIFY)
 
 static void exit_to_usermode_loop(struct pt_regs *regs, u32 cached_flags)
 {
@@ -147,9 +147,16 @@ static void exit_to_usermode_loop(struct pt_regs *regs, u32 cached_flags)
                /* We have work to do. */
                local_irq_enable();
 
-               if (cached_flags & _TIF_NEED_RESCHED)
+               if (cached_flags & _TIF_NEED_RESCHED_MASK)
                        schedule();
 
+#ifdef ARCH_RT_DELAYS_SIGNAL_SEND
+               if (unlikely(current->forced_info.si_signo)) {
+                       struct task_struct *t = current;
+                       force_sig_info(t->forced_info.si_signo, &t->forced_info, t);
+                       t->forced_info.si_signo = 0;
+               }
+#endif
                if (cached_flags & _TIF_UPROBE)
                        uprobe_notify_resume(regs);
 
index 4d980d1..f2c8c02 100644 (file)
@@ -322,8 +322,25 @@ END(ret_from_exception)
 ENTRY(resume_kernel)
        DISABLE_INTERRUPTS(CLBR_ANY)
 need_resched:
+       # preempt count == 0 + NEED_RS set?
        cmpl    $0, PER_CPU_VAR(__preempt_count)
+#ifndef CONFIG_PREEMPT_LAZY
        jnz     restore_all
+#else
+       jz test_int_off
+
+       # atleast preempt count == 0 ?
+       cmpl $_PREEMPT_ENABLED,PER_CPU_VAR(__preempt_count)
+       jne restore_all
+
+       movl    PER_CPU_VAR(current_task), %ebp
+       cmpl $0,TASK_TI_preempt_lazy_count(%ebp)        # non-zero preempt_lazy_count ?
+       jnz restore_all
+
+       testl $_TIF_NEED_RESCHED_LAZY, TASK_TI_flags(%ebp)
+       jz restore_all
+test_int_off:
+#endif
        testl   $X86_EFLAGS_IF, PT_EFLAGS(%esp) # interrupts off (exception path) ?
        jz      restore_all
        call    preempt_schedule_irq
index 657984f..dc7b6cb 100644 (file)
@@ -493,7 +493,23 @@ retint_kernel:
        btl     $9, EFLAGS(%rsp)                /* were interrupts off? */
        jnc     1f
 0:     cmpl    $0, PER_CPU_VAR(__preempt_count)
+#ifndef CONFIG_PREEMPT_LAZY
        jnz     1f
+#else
+       jz      do_preempt_schedule_irq
+
+       # atleast preempt count == 0 ?
+       cmpl $_PREEMPT_ENABLED,PER_CPU_VAR(__preempt_count)
+       jnz     1f
+
+       movq    PER_CPU_VAR(current_task), %rcx
+       cmpl    $0, TASK_TI_preempt_lazy_count(%rcx)
+       jnz     1f
+
+       bt      $TIF_NEED_RESCHED_LAZY,TASK_TI_flags(%rcx)
+       jnc     1f
+do_preempt_schedule_irq:
+#endif
        call    preempt_schedule_irq
        jmp     0b
 1:
@@ -838,6 +854,7 @@ bad_gs:
        jmp     2b
        .previous
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 /* Call softirq on interrupt stack. Interrupts are off. */
 ENTRY(do_softirq_own_stack)
        pushq   %rbp
@@ -850,6 +867,7 @@ ENTRY(do_softirq_own_stack)
        decl    PER_CPU_VAR(irq_count)
        ret
 END(do_softirq_own_stack)
+#endif
 
 #ifdef CONFIG_XEN
 idtentry xen_hypervisor_callback xen_do_hypervisor_callback has_error_code=0
index 1429a7c..85428df 100644 (file)
@@ -24,6 +24,7 @@ extern void __kernel_fpu_begin(void);
 extern void __kernel_fpu_end(void);
 extern void kernel_fpu_begin(void);
 extern void kernel_fpu_end(void);
+extern void kernel_fpu_resched(void);
 extern bool irq_fpu_usable(void);
 
 /*
index 4939f6e..92622d4 100644 (file)
@@ -79,17 +79,46 @@ static __always_inline void __preempt_count_sub(int val)
  * a decrement which hits zero means we have no preempt_count and should
  * reschedule.
  */
-static __always_inline bool __preempt_count_dec_and_test(void)
+static __always_inline bool ____preempt_count_dec_and_test(void)
 {
        GEN_UNARY_RMWcc("decl", __preempt_count, __percpu_arg(0), e);
 }
 
+static __always_inline bool __preempt_count_dec_and_test(void)
+{
+       if (____preempt_count_dec_and_test())
+               return true;
+#ifdef CONFIG_PREEMPT_LAZY
+       if (current_thread_info()->preempt_lazy_count)
+               return false;
+       return test_thread_flag(TIF_NEED_RESCHED_LAZY);
+#else
+       return false;
+#endif
+}
+
 /*
  * Returns true when we need to resched and can (barring IRQ state).
  */
 static __always_inline bool should_resched(int preempt_offset)
 {
+#ifdef CONFIG_PREEMPT_LAZY
+       u32 tmp;
+
+       tmp = raw_cpu_read_4(__preempt_count);
+       if (tmp == preempt_offset)
+               return true;
+
+       /* preempt count == 0 ? */
+       tmp &= ~PREEMPT_NEED_RESCHED;
+       if (tmp)
+               return false;
+       if (current_thread_info()->preempt_lazy_count)
+               return false;
+       return test_thread_flag(TIF_NEED_RESCHED_LAZY);
+#else
        return unlikely(raw_cpu_read_4(__preempt_count) == preempt_offset);
+#endif
 }
 
 #ifdef CONFIG_PREEMPT
index 8af22be..d132878 100644 (file)
@@ -27,6 +27,19 @@ typedef struct {
 #define SA_IA32_ABI    0x02000000u
 #define SA_X32_ABI     0x01000000u
 
+/*
+ * Because some traps use the IST stack, we must keep preemption
+ * disabled while calling do_trap(), but do_trap() may call
+ * force_sig_info() which will grab the signal spin_locks for the
+ * task, which in PREEMPT_RT_FULL are mutexes.  By defining
+ * ARCH_RT_DELAYS_SIGNAL_SEND the force_sig_info() will set
+ * TIF_NOTIFY_RESUME and set up the signal to be sent on exit of the
+ * trap.
+ */
+#if defined(CONFIG_PREEMPT_RT_FULL)
+#define ARCH_RT_DELAYS_SIGNAL_SEND
+#endif
+
 #ifndef CONFIG_COMPAT
 typedef sigset_t compat_sigset_t;
 #endif
index 743bd2d..e1fabfc 100644 (file)
@@ -64,7 +64,7 @@
  */
 static __always_inline void boot_init_stack_canary(void)
 {
-       u64 canary;
+       u64 uninitialized_var(canary);
        u64 tsc;
 
 #ifdef CONFIG_X86_64
@@ -75,8 +75,15 @@ static __always_inline void boot_init_stack_canary(void)
         * of randomness. The TSC only matters for very early init,
         * there it already has some randomness on most systems. Later
         * on during the bootup the random pool has true entropy too.
+        *
+        * For preempt-rt we need to weaken the randomness a bit, as
+        * we can't call into the random generator from atomic context
+        * due to locking constraints. We just leave canary
+        * uninitialized and use the TSC based randomness on top of it.
         */
+#ifndef CONFIG_PREEMPT_RT_FULL
        get_random_bytes(&canary, sizeof(canary));
+#endif
        tsc = rdtsc();
        canary += tsc + (tsc << 32UL);
 
index 0438f7f..32a8478 100644 (file)
@@ -54,12 +54,15 @@ struct task_struct;
 
 struct thread_info {
        unsigned long           flags;          /* low level flags */
+       int                     preempt_lazy_count;     /* 0 => lazy preemptable
+                                                          <0 => BUG */
        u32                     status;         /* thread synchronous flags */
 };
 
 #define INIT_THREAD_INFO(tsk)                  \
 {                                              \
        .flags          = 0,                    \
+       .preempt_lazy_count = 0,                \
 }
 
 #define init_stack             (init_thread_union.stack)
@@ -68,6 +71,10 @@ struct thread_info {
 
 #include <asm/asm-offsets.h>
 
+#define GET_THREAD_INFO(reg) \
+       _ASM_MOV PER_CPU_VAR(cpu_current_top_of_stack),reg ; \
+       _ASM_SUB $(THREAD_SIZE),reg ;
+
 #endif
 
 /*
@@ -93,6 +100,7 @@ struct thread_info {
 #define TIF_UPROBE             12      /* breakpointed or singlestepping */
 #define TIF_NOTSC              16      /* TSC is not accessible in userland */
 #define TIF_IA32               17      /* IA32 compatibility process */
+#define TIF_NEED_RESCHED_LAZY  18      /* lazy rescheduling necessary */
 #define TIF_NOHZ               19      /* in adaptive nohz mode */
 #define TIF_MEMDIE             20      /* is terminating due to OOM killer */
 #define TIF_POLLING_NRFLAG     21      /* idle is polling for TIF_NEED_RESCHED */
@@ -119,6 +127,7 @@ struct thread_info {
 #define _TIF_UPROBE            (1 << TIF_UPROBE)
 #define _TIF_NOTSC             (1 << TIF_NOTSC)
 #define _TIF_IA32              (1 << TIF_IA32)
+#define _TIF_NEED_RESCHED_LAZY (1 << TIF_NEED_RESCHED_LAZY)
 #define _TIF_NOHZ              (1 << TIF_NOHZ)
 #define _TIF_POLLING_NRFLAG    (1 << TIF_POLLING_NRFLAG)
 #define _TIF_IO_BITMAP         (1 << TIF_IO_BITMAP)
@@ -160,6 +169,8 @@ struct thread_info {
 #define _TIF_WORK_CTXSW_PREV (_TIF_WORK_CTXSW|_TIF_USER_RETURN_NOTIFY)
 #define _TIF_WORK_CTXSW_NEXT (_TIF_WORK_CTXSW)
 
+#define _TIF_NEED_RESCHED_MASK (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY)
+
 #define STACK_WARN             (THREAD_SIZE/8)
 
 /*
index 57ab86d..35d25e2 100644 (file)
@@ -624,9 +624,9 @@ struct bau_control {
        cycles_t                send_message;
        cycles_t                period_end;
        cycles_t                period_time;
-       spinlock_t              uvhub_lock;
-       spinlock_t              queue_lock;
-       spinlock_t              disable_lock;
+       raw_spinlock_t          uvhub_lock;
+       raw_spinlock_t          queue_lock;
+       raw_spinlock_t          disable_lock;
        /* tunables */
        int                     max_concurr;
        int                     max_concurr_const;
@@ -815,15 +815,15 @@ static inline int atom_asr(short i, struct atomic_short *v)
  * to be lowered below the current 'v'.  atomic_add_unless can only stop
  * on equal.
  */
-static inline int atomic_inc_unless_ge(spinlock_t *lock, atomic_t *v, int u)
+static inline int atomic_inc_unless_ge(raw_spinlock_t *lock, atomic_t *v, int u)
 {
-       spin_lock(lock);
+       raw_spin_lock(lock);
        if (atomic_read(v) >= u) {
-               spin_unlock(lock);
+               raw_spin_unlock(lock);
                return 0;
        }
        atomic_inc(v);
-       spin_unlock(lock);
+       raw_spin_unlock(lock);
        return 1;
 }
 
index c3fba8b..eb34bf9 100644 (file)
@@ -87,7 +87,9 @@ static u64 acpi_lapic_addr __initdata = APIC_DEFAULT_PHYS_BASE;
  *             ->ioapic_mutex
  *                     ->ioapic_lock
  */
+#ifdef CONFIG_X86_IO_APIC
 static DEFINE_MUTEX(acpi_ioapic_lock);
+#endif
 
 /* --------------------------------------------------------------------------
                               Boot-time Configuration
index c62e015..0cc7125 100644 (file)
@@ -36,6 +36,7 @@ void common(void) {
 
        BLANK();
        OFFSET(TASK_TI_flags, task_struct, thread_info.flags);
+       OFFSET(TASK_TI_preempt_lazy_count, task_struct, thread_info.preempt_lazy_count);
        OFFSET(TASK_addr_limit, task_struct, thread.addr_limit);
 
        BLANK();
@@ -91,4 +92,5 @@ void common(void) {
 
        BLANK();
        DEFINE(PTREGS_SIZE, sizeof(struct pt_regs));
+       DEFINE(_PREEMPT_ENABLED, PREEMPT_ENABLED);
 }
index 07188a0..decbe28 100644 (file)
@@ -41,6 +41,8 @@
 #include <linux/debugfs.h>
 #include <linux/irq_work.h>
 #include <linux/export.h>
+#include <linux/jiffies.h>
+#include <linux/swork.h>
 #include <linux/jump_label.h>
 
 #include <asm/processor.h>
@@ -1368,7 +1370,7 @@ void mce_log_therm_throt_event(__u64 status)
 static unsigned long check_interval = INITIAL_CHECK_INTERVAL;
 
 static DEFINE_PER_CPU(unsigned long, mce_next_interval); /* in jiffies */
-static DEFINE_PER_CPU(struct timer_list, mce_timer);
+static DEFINE_PER_CPU(struct hrtimer, mce_timer);
 
 static unsigned long mce_adjust_timer_default(unsigned long interval)
 {
@@ -1377,32 +1379,18 @@ static unsigned long mce_adjust_timer_default(unsigned long interval)
 
 static unsigned long (*mce_adjust_timer)(unsigned long interval) = mce_adjust_timer_default;
 
-static void __restart_timer(struct timer_list *t, unsigned long interval)
+static enum hrtimer_restart __restart_timer(struct hrtimer *timer, unsigned long interval)
 {
-       unsigned long when = jiffies + interval;
-       unsigned long flags;
-
-       local_irq_save(flags);
-
-       if (timer_pending(t)) {
-               if (time_before(when, t->expires))
-                       mod_timer(t, when);
-       } else {
-               t->expires = round_jiffies(when);
-               add_timer_on(t, smp_processor_id());
-       }
-
-       local_irq_restore(flags);
+       if (!interval)
+               return HRTIMER_NORESTART;
+       hrtimer_forward_now(timer, ns_to_ktime(jiffies_to_nsecs(interval)));
+       return HRTIMER_RESTART;
 }
 
-static void mce_timer_fn(unsigned long data)
+static enum hrtimer_restart mce_timer_fn(struct hrtimer *timer)
 {
-       struct timer_list *t = this_cpu_ptr(&mce_timer);
-       int cpu = smp_processor_id();
        unsigned long iv;
 
-       WARN_ON(cpu != data);
-
        iv = __this_cpu_read(mce_next_interval);
 
        if (mce_available(this_cpu_ptr(&cpu_info))) {
@@ -1425,7 +1413,7 @@ static void mce_timer_fn(unsigned long data)
 
 done:
        __this_cpu_write(mce_next_interval, iv);
-       __restart_timer(t, iv);
+       return __restart_timer(timer, iv);
 }
 
 /*
@@ -1433,7 +1421,7 @@ done:
  */
 void mce_timer_kick(unsigned long interval)
 {
-       struct timer_list *t = this_cpu_ptr(&mce_timer);
+       struct hrtimer *t = this_cpu_ptr(&mce_timer);
        unsigned long iv = __this_cpu_read(mce_next_interval);
 
        __restart_timer(t, interval);
@@ -1448,7 +1436,7 @@ static void mce_timer_delete_all(void)
        int cpu;
 
        for_each_online_cpu(cpu)
-               del_timer_sync(&per_cpu(mce_timer, cpu));
+               hrtimer_cancel(&per_cpu(mce_timer, cpu));
 }
 
 static void mce_do_trigger(struct work_struct *work)
@@ -1458,6 +1446,56 @@ static void mce_do_trigger(struct work_struct *work)
 
 static DECLARE_WORK(mce_trigger_work, mce_do_trigger);
 
+static void __mce_notify_work(struct swork_event *event)
+{
+       /* Not more than two messages every minute */
+       static DEFINE_RATELIMIT_STATE(ratelimit, 60*HZ, 2);
+
+       /* wake processes polling /dev/mcelog */
+       wake_up_interruptible(&mce_chrdev_wait);
+
+       /*
+        * There is no risk of missing notifications because
+        * work_pending is always cleared before the function is
+        * executed.
+        */
+       if (mce_helper[0] && !work_pending(&mce_trigger_work))
+               schedule_work(&mce_trigger_work);
+
+       if (__ratelimit(&ratelimit))
+               pr_info(HW_ERR "Machine check events logged\n");
+}
+
+#ifdef CONFIG_PREEMPT_RT_FULL
+static bool notify_work_ready __read_mostly;
+static struct swork_event notify_work;
+
+static int mce_notify_work_init(void)
+{
+       int err;
+
+       err = swork_get();
+       if (err)
+               return err;
+
+       INIT_SWORK(&notify_work, __mce_notify_work);
+       notify_work_ready = true;
+       return 0;
+}
+
+static void mce_notify_work(void)
+{
+       if (notify_work_ready)
+               swork_queue(&notify_work);
+}
+#else
+static void mce_notify_work(void)
+{
+       __mce_notify_work(NULL);
+}
+static inline int mce_notify_work_init(void) { return 0; }
+#endif
+
 /*
  * Notify the user(s) about new machine check events.
  * Can be called from interrupt context, but not from machine check/NMI
@@ -1465,19 +1503,8 @@ static DECLARE_WORK(mce_trigger_work, mce_do_trigger);
  */
 int mce_notify_irq(void)
 {
-       /* Not more than two messages every minute */
-       static DEFINE_RATELIMIT_STATE(ratelimit, 60*HZ, 2);
-
        if (test_and_clear_bit(0, &mce_need_notify)) {
-               /* wake processes polling /dev/mcelog */
-               wake_up_interruptible(&mce_chrdev_wait);
-
-               if (mce_helper[0])
-                       schedule_work(&mce_trigger_work);
-
-               if (__ratelimit(&ratelimit))
-                       pr_info(HW_ERR "Machine check events logged\n");
-
+               mce_notify_work();
                return 1;
        }
        return 0;
@@ -1758,7 +1785,7 @@ static void __mcheck_cpu_clear_vendor(struct cpuinfo_x86 *c)
        }
 }
 
-static void mce_start_timer(unsigned int cpu, struct timer_list *t)
+static void mce_start_timer(unsigned int cpu, struct hrtimer *t)
 {
        unsigned long iv = check_interval * HZ;
 
@@ -1767,16 +1794,17 @@ static void mce_start_timer(unsigned int cpu, struct timer_list *t)
 
        per_cpu(mce_next_interval, cpu) = iv;
 
-       t->expires = round_jiffies(jiffies + iv);
-       add_timer_on(t, cpu);
+       hrtimer_start_range_ns(t, ns_to_ktime(jiffies_to_usecs(iv) * 1000ULL),
+                       0, HRTIMER_MODE_REL_PINNED);
 }
 
 static void __mcheck_cpu_init_timer(void)
 {
-       struct timer_list *t = this_cpu_ptr(&mce_timer);
+       struct hrtimer *t = this_cpu_ptr(&mce_timer);
        unsigned int cpu = smp_processor_id();
 
-       setup_pinned_timer(t, mce_timer_fn, cpu);
+       hrtimer_init(t, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+       t->function = mce_timer_fn;
        mce_start_timer(cpu, t);
 }
 
@@ -2521,6 +2549,8 @@ static void mce_disable_cpu(void *h)
        if (!mce_available(raw_cpu_ptr(&cpu_info)))
                return;
 
+       hrtimer_cancel(this_cpu_ptr(&mce_timer));
+
        if (!(action & CPU_TASKS_FROZEN))
                cmci_clear();
 
@@ -2543,6 +2573,7 @@ static void mce_reenable_cpu(void *h)
                if (b->init)
                        wrmsrl(msr_ops.ctl(i), b->ctl);
        }
+       __mcheck_cpu_init_timer();
 }
 
 /* Get notified when a cpu comes on/off. Be hotplug friendly. */
@@ -2550,7 +2581,6 @@ static int
 mce_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu)
 {
        unsigned int cpu = (unsigned long)hcpu;
-       struct timer_list *t = &per_cpu(mce_timer, cpu);
 
        switch (action & ~CPU_TASKS_FROZEN) {
        case CPU_ONLINE:
@@ -2570,11 +2600,9 @@ mce_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu)
                break;
        case CPU_DOWN_PREPARE:
                smp_call_function_single(cpu, mce_disable_cpu, &action, 1);
-               del_timer_sync(t);
                break;
        case CPU_DOWN_FAILED:
                smp_call_function_single(cpu, mce_reenable_cpu, &action, 1);
-               mce_start_timer(cpu, t);
                break;
        }
 
@@ -2613,6 +2641,10 @@ static __init int mcheck_init_device(void)
                goto err_out;
        }
 
+       err = mce_notify_work_init();
+       if (err)
+               goto err_out;
+
        if (!zalloc_cpumask_var(&mce_device_initialized, GFP_KERNEL)) {
                err = -ENOMEM;
                goto err_out;
index fc96511..d7f4216 100644 (file)
@@ -138,6 +138,18 @@ void kernel_fpu_end(void)
 }
 EXPORT_SYMBOL_GPL(kernel_fpu_end);
 
+void kernel_fpu_resched(void)
+{
+       WARN_ON_FPU(!this_cpu_read(in_kernel_fpu));
+
+       if (should_resched(PREEMPT_OFFSET)) {
+               kernel_fpu_end();
+               cond_resched();
+               kernel_fpu_begin();
+       }
+}
+EXPORT_SYMBOL_GPL(kernel_fpu_resched);
+
 /*
  * CR0::TS save/restore functions:
  */
index 5aaa39a..51fae83 100644 (file)
@@ -129,6 +129,7 @@ void irq_ctx_init(int cpu)
               cpu, per_cpu(hardirq_stack, cpu),  per_cpu(softirq_stack, cpu));
 }
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 void do_softirq_own_stack(void)
 {
        struct irq_stack *irqstk;
@@ -145,6 +146,7 @@ void do_softirq_own_stack(void)
 
        call_on_stack(__do_softirq, isp);
 }
+#endif
 
 bool handle_irq(struct irq_desc *desc, struct pt_regs *regs)
 {
index 4ca26fc..287d69c 100644 (file)
@@ -35,6 +35,7 @@
 #include <linux/uaccess.h>
 #include <linux/io.h>
 #include <linux/kdebug.h>
+#include <linux/highmem.h>
 
 #include <asm/pgtable.h>
 #include <asm/ldt.h>
@@ -204,6 +205,35 @@ start_thread(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp)
 }
 EXPORT_SYMBOL_GPL(start_thread);
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+static void switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p)
+{
+       int i;
+
+       /*
+        * Clear @prev's kmap_atomic mappings
+        */
+       for (i = 0; i < prev_p->kmap_idx; i++) {
+               int idx = i + KM_TYPE_NR * smp_processor_id();
+               pte_t *ptep = kmap_pte - idx;
+
+               kpte_clear_flush(ptep, __fix_to_virt(FIX_KMAP_BEGIN + idx));
+       }
+       /*
+        * Restore @next_p's kmap_atomic mappings
+        */
+       for (i = 0; i < next_p->kmap_idx; i++) {
+               int idx = i + KM_TYPE_NR * smp_processor_id();
+
+               if (!pte_none(next_p->kmap_pte[i]))
+                       set_pte(kmap_pte - idx, next_p->kmap_pte[i]);
+       }
+}
+#else
+static inline void
+switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p) { }
+#endif
+
 
 /*
  *     switch_to(x,y) should switch tasks from x to y.
@@ -275,6 +305,8 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 
        switch_to_extra(prev_p, next_p);
 
+       switch_kmaps(prev_p, next_p);
+
        /*
         * Leave lazy mode, flushing any hypercalls made here.
         * This must be done before restoring TLS segments so
index bfed29a..2739b2c 100644 (file)
@@ -1978,6 +1978,7 @@ int kvm_create_lapic(struct kvm_vcpu *vcpu)
        hrtimer_init(&apic->lapic_timer.timer, CLOCK_MONOTONIC,
                     HRTIMER_MODE_ABS_PINNED);
        apic->lapic_timer.timer.function = apic_timer_fn;
+       apic->lapic_timer.timer.irqsafe = 1;
 
        /*
         * APIC is created enabled. This will prevent kvm_lapic_set_base from
index 3c0f9be..d95afa6 100644 (file)
@@ -6221,6 +6221,13 @@ int kvm_arch_init(void *opaque)
                goto out;
        }
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+       if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) {
+               printk(KERN_ERR "RT requires X86_FEATURE_CONSTANT_TSC\n");
+               return -EOPNOTSUPP;
+       }
+#endif
+
        r = kvm_mmu_module_init();
        if (r)
                goto out_free_percpu;
index 6d18b70..f752724 100644 (file)
@@ -32,10 +32,11 @@ EXPORT_SYMBOL(kunmap);
  */
 void *kmap_atomic_prot(struct page *page, pgprot_t prot)
 {
+       pte_t pte = mk_pte(page, prot);
        unsigned long vaddr;
        int idx, type;
 
-       preempt_disable();
+       preempt_disable_nort();
        pagefault_disable();
 
        if (!PageHighMem(page))
@@ -45,7 +46,10 @@ void *kmap_atomic_prot(struct page *page, pgprot_t prot)
        idx = type + KM_TYPE_NR*smp_processor_id();
        vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
        BUG_ON(!pte_none(*(kmap_pte-idx)));
-       set_pte(kmap_pte-idx, mk_pte(page, prot));
+#ifdef CONFIG_PREEMPT_RT_FULL
+       current->kmap_pte[type] = pte;
+#endif
+       set_pte(kmap_pte-idx, pte);
        arch_flush_lazy_mmu_mode();
 
        return (void *)vaddr;
@@ -88,6 +92,9 @@ void __kunmap_atomic(void *kvaddr)
                 * is a bad idea also, in case the page changes cacheability
                 * attributes or becomes a protected page in a hypervisor.
                 */
+#ifdef CONFIG_PREEMPT_RT_FULL
+               current->kmap_pte[type] = __pte(0);
+#endif
                kpte_clear_flush(kmap_pte-idx, vaddr);
                kmap_atomic_idx_pop();
                arch_flush_lazy_mmu_mode();
@@ -100,7 +107,7 @@ void __kunmap_atomic(void *kvaddr)
 #endif
 
        pagefault_enable();
-       preempt_enable();
+       preempt_enable_nort();
 }
 EXPORT_SYMBOL(__kunmap_atomic);
 
index ada98b3..585f682 100644 (file)
@@ -56,6 +56,7 @@ EXPORT_SYMBOL_GPL(iomap_free);
 
 void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot)
 {
+       pte_t pte = pfn_pte(pfn, prot);
        unsigned long vaddr;
        int idx, type;
 
@@ -65,7 +66,12 @@ void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot)
        type = kmap_atomic_idx_push();
        idx = type + KM_TYPE_NR * smp_processor_id();
        vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-       set_pte(kmap_pte - idx, pfn_pte(pfn, prot));
+       WARN_ON(!pte_none(*(kmap_pte - idx)));
+
+#ifdef CONFIG_PREEMPT_RT_FULL
+       current->kmap_pte[type] = pte;
+#endif
+       set_pte(kmap_pte - idx, pte);
        arch_flush_lazy_mmu_mode();
 
        return (void *)vaddr;
@@ -113,6 +119,9 @@ iounmap_atomic(void __iomem *kvaddr)
                 * is a bad idea also, in case the page changes cacheability
                 * attributes or becomes a protected page in a hypervisor.
                 */
+#ifdef CONFIG_PREEMPT_RT_FULL
+               current->kmap_pte[type] = __pte(0);
+#endif
                kpte_clear_flush(kmap_pte-idx, vaddr);
                kmap_atomic_idx_pop();
        }
index 1271bc9..83d9fde 100644 (file)
@@ -215,7 +215,15 @@ static void cpa_flush_array(unsigned long *start, int numpages, int cache,
                            int in_flags, struct page **pages)
 {
        unsigned int i, level;
+#ifdef CONFIG_PREEMPT
+       /*
+        * Avoid wbinvd() because it causes latencies on all CPUs,
+        * regardless of any CPU isolation that may be in effect.
+        */
+       unsigned long do_wbinvd = 0;
+#else
        unsigned long do_wbinvd = cache && numpages >= 1024; /* 4M threshold */
+#endif
 
        BUG_ON(irqs_disabled());
 
index 16d4967..cb5382b 100644 (file)
@@ -748,9 +748,9 @@ static void destination_plugged(struct bau_desc *bau_desc,
 
                quiesce_local_uvhub(hmaster);
 
-               spin_lock(&hmaster->queue_lock);
+               raw_spin_lock(&hmaster->queue_lock);
                reset_with_ipi(&bau_desc->distribution, bcp);
-               spin_unlock(&hmaster->queue_lock);
+               raw_spin_unlock(&hmaster->queue_lock);
 
                end_uvhub_quiesce(hmaster);
 
@@ -770,9 +770,9 @@ static void destination_timeout(struct bau_desc *bau_desc,
 
                quiesce_local_uvhub(hmaster);
 
-               spin_lock(&hmaster->queue_lock);
+               raw_spin_lock(&hmaster->queue_lock);
                reset_with_ipi(&bau_desc->distribution, bcp);
-               spin_unlock(&hmaster->queue_lock);
+               raw_spin_unlock(&hmaster->queue_lock);
 
                end_uvhub_quiesce(hmaster);
 
@@ -793,7 +793,7 @@ static void disable_for_period(struct bau_control *bcp, struct ptc_stats *stat)
        cycles_t tm1;
 
        hmaster = bcp->uvhub_master;
-       spin_lock(&hmaster->disable_lock);
+       raw_spin_lock(&hmaster->disable_lock);
        if (!bcp->baudisabled) {
                stat->s_bau_disabled++;
                tm1 = get_cycles();
@@ -806,7 +806,7 @@ static void disable_for_period(struct bau_control *bcp, struct ptc_stats *stat)
                        }
                }
        }
-       spin_unlock(&hmaster->disable_lock);
+       raw_spin_unlock(&hmaster->disable_lock);
 }
 
 static void count_max_concurr(int stat, struct bau_control *bcp,
@@ -869,7 +869,7 @@ static void record_send_stats(cycles_t time1, cycles_t time2,
  */
 static void uv1_throttle(struct bau_control *hmaster, struct ptc_stats *stat)
 {
-       spinlock_t *lock = &hmaster->uvhub_lock;
+       raw_spinlock_t *lock = &hmaster->uvhub_lock;
        atomic_t *v;
 
        v = &hmaster->active_descriptor_count;
@@ -1002,7 +1002,7 @@ static int check_enable(struct bau_control *bcp, struct ptc_stats *stat)
        struct bau_control *hmaster;
 
        hmaster = bcp->uvhub_master;
-       spin_lock(&hmaster->disable_lock);
+       raw_spin_lock(&hmaster->disable_lock);
        if (bcp->baudisabled && (get_cycles() >= bcp->set_bau_on_time)) {
                stat->s_bau_reenabled++;
                for_each_present_cpu(tcpu) {
@@ -1014,10 +1014,10 @@ static int check_enable(struct bau_control *bcp, struct ptc_stats *stat)
                                tbcp->period_giveups = 0;
                        }
                }
-               spin_unlock(&hmaster->disable_lock);
+               raw_spin_unlock(&hmaster->disable_lock);
                return 0;
        }
-       spin_unlock(&hmaster->disable_lock);
+       raw_spin_unlock(&hmaster->disable_lock);
        return -1;
 }
 
@@ -1940,9 +1940,9 @@ static void __init init_per_cpu_tunables(void)
                bcp->cong_reps                  = congested_reps;
                bcp->disabled_period            = sec_2_cycles(disabled_period);
                bcp->giveup_limit               = giveup_limit;
-               spin_lock_init(&bcp->queue_lock);
-               spin_lock_init(&bcp->uvhub_lock);
-               spin_lock_init(&bcp->disable_lock);
+               raw_spin_lock_init(&bcp->queue_lock);
+               raw_spin_lock_init(&bcp->uvhub_lock);
+               raw_spin_lock_init(&bcp->disable_lock);
        }
 }
 
index b333fc4..8b85916 100644 (file)
@@ -57,7 +57,7 @@ static DEFINE_PER_CPU(struct clock_event_device, cpu_ced);
 
 /* There is one of these allocated per node */
 struct uv_rtc_timer_head {
-       spinlock_t      lock;
+       raw_spinlock_t  lock;
        /* next cpu waiting for timer, local node relative: */
        int             next_cpu;
        /* number of cpus on this node: */
@@ -177,7 +177,7 @@ static __init int uv_rtc_allocate_timers(void)
                                uv_rtc_deallocate_timers();
                                return -ENOMEM;
                        }
-                       spin_lock_init(&head->lock);
+                       raw_spin_lock_init(&head->lock);
                        head->ncpus = uv_blade_nr_possible_cpus(bid);
                        head->next_cpu = -1;
                        blade_info[bid] = head;
@@ -231,7 +231,7 @@ static int uv_rtc_set_timer(int cpu, u64 expires)
        unsigned long flags;
        int next_cpu;
 
-       spin_lock_irqsave(&head->lock, flags);
+       raw_spin_lock_irqsave(&head->lock, flags);
 
        next_cpu = head->next_cpu;
        *t = expires;
@@ -243,12 +243,12 @@ static int uv_rtc_set_timer(int cpu, u64 expires)
                if (uv_setup_intr(cpu, expires)) {
                        *t = ULLONG_MAX;
                        uv_rtc_find_next_timer(head, pnode);
-                       spin_unlock_irqrestore(&head->lock, flags);
+                       raw_spin_unlock_irqrestore(&head->lock, flags);
                        return -ETIME;
                }
        }
 
-       spin_unlock_irqrestore(&head->lock, flags);
+       raw_spin_unlock_irqrestore(&head->lock, flags);
        return 0;
 }
 
@@ -267,7 +267,7 @@ static int uv_rtc_unset_timer(int cpu, int force)
        unsigned long flags;
        int rc = 0;
 
-       spin_lock_irqsave(&head->lock, flags);
+       raw_spin_lock_irqsave(&head->lock, flags);
 
        if ((head->next_cpu == bcpu && uv_read_rtc(NULL) >= *t) || force)
                rc = 1;
@@ -279,7 +279,7 @@ static int uv_rtc_unset_timer(int cpu, int force)
                        uv_rtc_find_next_timer(head, pnode);
        }
 
-       spin_unlock_irqrestore(&head->lock, flags);
+       raw_spin_unlock_irqrestore(&head->lock, flags);
 
        return rc;
 }
@@ -299,13 +299,18 @@ static int uv_rtc_unset_timer(int cpu, int force)
 static cycle_t uv_read_rtc(struct clocksource *cs)
 {
        unsigned long offset;
+       cycle_t cycles;
 
+       preempt_disable();
        if (uv_get_min_hub_revision_id() == 1)
                offset = 0;
        else
                offset = (uv_blade_processor_id() * L1_CACHE_BYTES) % PAGE_SIZE;
 
-       return (cycle_t)uv_read_local_mmr(UVH_RTC | offset);
+       cycles = (cycle_t)uv_read_local_mmr(UVH_RTC | offset);
+       preempt_enable();
+
+       return cycles;
 }
 
 /*
index 27621cd..ed696d1 100644 (file)
@@ -127,6 +127,9 @@ void blk_rq_init(struct request_queue *q, struct request *rq)
 
        INIT_LIST_HEAD(&rq->queuelist);
        INIT_LIST_HEAD(&rq->timeout_list);
+#ifdef CONFIG_PREEMPT_RT_FULL
+       INIT_WORK(&rq->work, __blk_mq_complete_request_remote_work);
+#endif
        rq->cpu = -1;
        rq->q = q;
        rq->__sector = (sector_t) -1;
@@ -235,7 +238,7 @@ EXPORT_SYMBOL(blk_start_queue_async);
  **/
 void blk_start_queue(struct request_queue *q)
 {
-       WARN_ON(!in_interrupt() && !irqs_disabled());
+       WARN_ON_NONRT(!in_interrupt() && !irqs_disabled());
 
        queue_flag_clear(QUEUE_FLAG_STOPPED, q);
        __blk_run_queue(q);
@@ -674,12 +677,21 @@ void blk_queue_exit(struct request_queue *q)
        percpu_ref_put(&q->q_usage_counter);
 }
 
+static void blk_queue_usage_counter_release_swork(struct swork_event *sev)
+{
+       struct request_queue *q =
+               container_of(sev, struct request_queue, mq_pcpu_wake);
+
+       wake_up_all(&q->mq_freeze_wq);
+}
+
 static void blk_queue_usage_counter_release(struct percpu_ref *ref)
 {
        struct request_queue *q =
                container_of(ref, struct request_queue, q_usage_counter);
 
-       wake_up_all(&q->mq_freeze_wq);
+       if (wq_has_sleeper(&q->mq_freeze_wq))
+               swork_queue(&q->mq_pcpu_wake);
 }
 
 static void blk_rq_timed_out_timer(unsigned long data)
@@ -753,6 +765,7 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
        __set_bit(QUEUE_FLAG_BYPASS, &q->queue_flags);
 
        init_waitqueue_head(&q->mq_freeze_wq);
+       INIT_SWORK(&q->mq_pcpu_wake, blk_queue_usage_counter_release_swork);
 
        /*
         * Init percpu_ref in atomic mode so that it's faster to shutdown.
@@ -3205,7 +3218,7 @@ static void queue_unplugged(struct request_queue *q, unsigned int depth,
                blk_run_queue_async(q);
        else
                __blk_run_queue(q);
-       spin_unlock(q->queue_lock);
+       spin_unlock_irq(q->queue_lock);
 }
 
 static void flush_plug_callbacks(struct blk_plug *plug, bool from_schedule)
@@ -3253,7 +3266,6 @@ EXPORT_SYMBOL(blk_check_plugged);
 void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule)
 {
        struct request_queue *q;
-       unsigned long flags;
        struct request *rq;
        LIST_HEAD(list);
        unsigned int depth;
@@ -3273,11 +3285,6 @@ void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule)
        q = NULL;
        depth = 0;
 
-       /*
-        * Save and disable interrupts here, to avoid doing it for every
-        * queue lock we have to take.
-        */
-       local_irq_save(flags);
        while (!list_empty(&list)) {
                rq = list_entry_rq(list.next);
                list_del_init(&rq->queuelist);
@@ -3290,7 +3297,7 @@ void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule)
                                queue_unplugged(q, depth, from_schedule);
                        q = rq->q;
                        depth = 0;
-                       spin_lock(q->queue_lock);
+                       spin_lock_irq(q->queue_lock);
                }
 
                /*
@@ -3317,8 +3324,6 @@ void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule)
         */
        if (q)
                queue_unplugged(q, depth, from_schedule);
-
-       local_irq_restore(flags);
 }
 
 void blk_finish_plug(struct blk_plug *plug)
@@ -3567,6 +3572,8 @@ int __init blk_dev_init(void)
        if (!kblockd_workqueue)
                panic("Failed to create kblockd\n");
 
+       BUG_ON(swork_get());
+
        request_cachep = kmem_cache_create("blkdev_requests",
                        sizeof(struct request), 0, SLAB_PANIC, NULL);
 
index 381cb50..dc87852 100644 (file)
@@ -7,6 +7,7 @@
 #include <linux/bio.h>
 #include <linux/blkdev.h>
 #include <linux/slab.h>
+#include <linux/delay.h>
 
 #include "blk.h"
 
@@ -109,7 +110,7 @@ static void ioc_release_fn(struct work_struct *work)
                        spin_unlock(q->queue_lock);
                } else {
                        spin_unlock_irqrestore(&ioc->lock, flags);
-                       cpu_relax();
+                       cpu_chill();
                        spin_lock_irqsave_nested(&ioc->lock, flags, 1);
                }
        }
@@ -187,7 +188,7 @@ retry:
                        spin_unlock(icq->q->queue_lock);
                } else {
                        spin_unlock_irqrestore(&ioc->lock, flags);
-                       cpu_relax();
+                       cpu_chill();
                        goto retry;
                }
        }
index e0ed731..5c9f747 100644 (file)
@@ -177,6 +177,9 @@ static void blk_mq_rq_ctx_init(struct request_queue *q, struct blk_mq_ctx *ctx,
        rq->resid_len = 0;
        rq->sense = NULL;
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+       INIT_WORK(&rq->work, __blk_mq_complete_request_remote_work);
+#endif
        INIT_LIST_HEAD(&rq->timeout_list);
        rq->timeout = 0;
 
@@ -345,6 +348,17 @@ void blk_mq_end_request(struct request *rq, int error)
 }
 EXPORT_SYMBOL(blk_mq_end_request);
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+
+void __blk_mq_complete_request_remote_work(struct work_struct *work)
+{
+       struct request *rq = container_of(work, struct request, work);
+
+       rq->q->softirq_done_fn(rq);
+}
+
+#else
+
 static void __blk_mq_complete_request_remote(void *data)
 {
        struct request *rq = data;
@@ -352,6 +366,8 @@ static void __blk_mq_complete_request_remote(void *data)
        rq->q->softirq_done_fn(rq);
 }
 
+#endif
+
 static void blk_mq_ipi_complete_request(struct request *rq)
 {
        struct blk_mq_ctx *ctx = rq->mq_ctx;
@@ -363,19 +379,23 @@ static void blk_mq_ipi_complete_request(struct request *rq)
                return;
        }
 
-       cpu = get_cpu();
+       cpu = get_cpu_light();
        if (!test_bit(QUEUE_FLAG_SAME_FORCE, &rq->q->queue_flags))
                shared = cpus_share_cache(cpu, ctx->cpu);
 
        if (cpu != ctx->cpu && !shared && cpu_online(ctx->cpu)) {
+#ifdef CONFIG_PREEMPT_RT_FULL
+               schedule_work_on(ctx->cpu, &rq->work);
+#else
                rq->csd.func = __blk_mq_complete_request_remote;
                rq->csd.info = rq;
                rq->csd.flags = 0;
                smp_call_function_single_async(ctx->cpu, &rq->csd);
+#endif
        } else {
                rq->q->softirq_done_fn(rq);
        }
-       put_cpu();
+       put_cpu_light();
 }
 
 static void __blk_mq_complete_request(struct request *rq)
@@ -906,14 +926,14 @@ void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async)
                return;
 
        if (!async && !(hctx->flags & BLK_MQ_F_BLOCKING)) {
-               int cpu = get_cpu();
+               int cpu = get_cpu_light();
                if (cpumask_test_cpu(cpu, hctx->cpumask)) {
                        __blk_mq_run_hw_queue(hctx);
-                       put_cpu();
+                       put_cpu_light();
                        return;
                }
 
-               put_cpu();
+               put_cpu_light();
        }
 
        kblockd_schedule_work_on(blk_mq_hctx_next_cpu(hctx), &hctx->run_work);
index c55bcf6..c26a84d 100644 (file)
@@ -73,12 +73,12 @@ static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q,
  */
 static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q)
 {
-       return __blk_mq_get_ctx(q, get_cpu());
+       return __blk_mq_get_ctx(q, get_cpu_light());
 }
 
 static inline void blk_mq_put_ctx(struct blk_mq_ctx *ctx)
 {
-       put_cpu();
+       put_cpu_light();
 }
 
 struct blk_mq_alloc_data {
index 06cf980..c403426 100644 (file)
@@ -51,6 +51,7 @@ static void trigger_softirq(void *data)
                raise_softirq_irqoff(BLOCK_SOFTIRQ);
 
        local_irq_restore(flags);
+       preempt_check_resched_rt();
 }
 
 /*
@@ -89,6 +90,7 @@ static int blk_softirq_cpu_dead(unsigned int cpu)
                         this_cpu_ptr(&blk_cpu_done));
        raise_softirq_irqoff(BLOCK_SOFTIRQ);
        local_irq_enable();
+       preempt_check_resched_rt();
 
        return 0;
 }
@@ -141,6 +143,7 @@ do_local:
                goto do_local;
 
        local_irq_restore(flags);
+       preempt_check_resched_rt();
 }
 
 /**
index 1cb5dd3..2f1ec8a 100644 (file)
@@ -55,11 +55,11 @@ static void bounce_copy_vec(struct bio_vec *to, unsigned char *vfrom)
        unsigned long flags;
        unsigned char *vto;
 
-       local_irq_save(flags);
+       local_irq_save_nort(flags);
        vto = kmap_atomic(to->bv_page);
        memcpy(vto + to->bv_offset, vfrom, to->bv_len);
        kunmap_atomic(vto);
-       local_irq_restore(flags);
+       local_irq_restore_nort(flags);
 }
 
 #else /* CONFIG_HIGHMEM */
index 9e5b243..0287942 100644 (file)
@@ -723,13 +723,13 @@ EXPORT_SYMBOL_GPL(crypto_spawn_tfm2);
 
 int crypto_register_notifier(struct notifier_block *nb)
 {
-       return blocking_notifier_chain_register(&crypto_chain, nb);
+       return srcu_notifier_chain_register(&crypto_chain, nb);
 }
 EXPORT_SYMBOL_GPL(crypto_register_notifier);
 
 int crypto_unregister_notifier(struct notifier_block *nb)
 {
-       return blocking_notifier_chain_unregister(&crypto_chain, nb);
+       return srcu_notifier_chain_unregister(&crypto_chain, nb);
 }
 EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
 
index b47796b..1df402c 100644 (file)
@@ -32,7 +32,7 @@ EXPORT_SYMBOL_GPL(crypto_alg_list);
 DECLARE_RWSEM(crypto_alg_sem);
 EXPORT_SYMBOL_GPL(crypto_alg_sem);
 
-BLOCKING_NOTIFIER_HEAD(crypto_chain);
+SRCU_NOTIFIER_HEAD(crypto_chain);
 EXPORT_SYMBOL_GPL(crypto_chain);
 
 static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg);
@@ -237,10 +237,10 @@ int crypto_probing_notify(unsigned long val, void *v)
 {
        int ok;
 
-       ok = blocking_notifier_call_chain(&crypto_chain, val, v);
+       ok = srcu_notifier_call_chain(&crypto_chain, val, v);
        if (ok == NOTIFY_DONE) {
                request_module("cryptomgr");
-               ok = blocking_notifier_call_chain(&crypto_chain, val, v);
+               ok = srcu_notifier_call_chain(&crypto_chain, val, v);
        }
 
        return ok;
index 6184c42..10c8893 100644 (file)
@@ -47,7 +47,7 @@ struct crypto_larval {
 
 extern struct list_head crypto_alg_list;
 extern struct rw_semaphore crypto_alg_sem;
-extern struct blocking_notifier_head crypto_chain;
+extern struct srcu_notifier_head crypto_chain;
 
 #ifdef CONFIG_PROC_FS
 void __init crypto_init_proc(void);
@@ -145,7 +145,7 @@ static inline int crypto_is_moribund(struct crypto_alg *alg)
 
 static inline void crypto_notify(unsigned long val, void *v)
 {
-       blocking_notifier_call_chain(&crypto_chain, val, v);
+       srcu_notifier_call_chain(&crypto_chain, val, v);
 }
 
 #endif /* _CRYPTO_INTERNAL_H */
index 750fa82..441edf5 100644 (file)
@@ -116,7 +116,7 @@ ACPI_GLOBAL(u8, acpi_gbl_global_lock_pending);
  * interrupt level
  */
 ACPI_GLOBAL(acpi_spinlock, acpi_gbl_gpe_lock); /* For GPE data structs and registers */
-ACPI_GLOBAL(acpi_spinlock, acpi_gbl_hardware_lock);    /* For ACPI H/W except GPE registers */
+ACPI_GLOBAL(acpi_raw_spinlock, acpi_gbl_hardware_lock);        /* For ACPI H/W except GPE registers */
 ACPI_GLOBAL(acpi_spinlock, acpi_gbl_reference_count_lock);
 
 /* Mutex for _OSI support */
index 3b7fb99..696bf8e 100644 (file)
@@ -363,14 +363,14 @@ acpi_status acpi_hw_clear_acpi_status(void)
                          ACPI_BITMASK_ALL_FIXED_STATUS,
                          ACPI_FORMAT_UINT64(acpi_gbl_xpm1a_status.address)));
 
-       lock_flags = acpi_os_acquire_lock(acpi_gbl_hardware_lock);
+       raw_spin_lock_irqsave(acpi_gbl_hardware_lock, lock_flags);
 
        /* Clear the fixed events in PM1 A/B */
 
        status = acpi_hw_register_write(ACPI_REGISTER_PM1_STATUS,
                                        ACPI_BITMASK_ALL_FIXED_STATUS);
 
-       acpi_os_release_lock(acpi_gbl_hardware_lock, lock_flags);
+       raw_spin_unlock_irqrestore(acpi_gbl_hardware_lock, lock_flags);
 
        if (ACPI_FAILURE(status)) {
                goto exit;
index 98c26ff..6e236f2 100644 (file)
@@ -373,7 +373,7 @@ acpi_status acpi_write_bit_register(u32 register_id, u32 value)
                return_ACPI_STATUS(AE_BAD_PARAMETER);
        }
 
-       lock_flags = acpi_os_acquire_lock(acpi_gbl_hardware_lock);
+       raw_spin_lock_irqsave(acpi_gbl_hardware_lock, lock_flags);
 
        /*
         * At this point, we know that the parent register is one of the
@@ -434,7 +434,7 @@ acpi_status acpi_write_bit_register(u32 register_id, u32 value)
 
 unlock_and_exit:
 
-       acpi_os_release_lock(acpi_gbl_hardware_lock, lock_flags);
+       raw_spin_unlock_irqrestore(acpi_gbl_hardware_lock, lock_flags);
        return_ACPI_STATUS(status);
 }
 
index 1507337..357e7ca 100644 (file)
@@ -88,7 +88,7 @@ acpi_status acpi_ut_mutex_initialize(void)
                return_ACPI_STATUS (status);
        }
 
-       status = acpi_os_create_lock (&acpi_gbl_hardware_lock);
+       status = acpi_os_create_raw_lock (&acpi_gbl_hardware_lock);
        if (ACPI_FAILURE (status)) {
                return_ACPI_STATUS (status);
        }
@@ -145,7 +145,7 @@ void acpi_ut_mutex_terminate(void)
        /* Delete the spinlocks */
 
        acpi_os_delete_lock(acpi_gbl_gpe_lock);
-       acpi_os_delete_lock(acpi_gbl_hardware_lock);
+       acpi_os_delete_raw_lock(acpi_gbl_hardware_lock);
        acpi_os_delete_lock(acpi_gbl_reference_count_lock);
 
        /* Delete the reader/writer lock */
index 0edd83c..3950e90 100644 (file)
@@ -678,9 +678,9 @@ unsigned int ata_sff_data_xfer_noirq(struct ata_device *dev, unsigned char *buf,
        unsigned long flags;
        unsigned int consumed;
 
-       local_irq_save(flags);
+       local_irq_save_nort(flags);
        consumed = ata_sff_data_xfer32(dev, buf, buflen, rw);
-       local_irq_restore(flags);
+       local_irq_restore_nort(flags);
 
        return consumed;
 }
@@ -723,7 +723,7 @@ static void ata_pio_sector(struct ata_queued_cmd *qc)
                unsigned long flags;
 
                /* FIXME: use a bounce buffer */
-               local_irq_save(flags);
+               local_irq_save_nort(flags);
                buf = kmap_atomic(page);
 
                /* do the actual data transfer */
@@ -731,7 +731,7 @@ static void ata_pio_sector(struct ata_queued_cmd *qc)
                                       do_write);
 
                kunmap_atomic(buf);
-               local_irq_restore(flags);
+               local_irq_restore_nort(flags);
        } else {
                buf = page_address(page);
                ap->ops->sff_data_xfer(qc->dev, buf + offset, qc->sect_size,
@@ -870,7 +870,7 @@ next_sg:
                unsigned long flags;
 
                /* FIXME: use bounce buffer */
-               local_irq_save(flags);
+               local_irq_save_nort(flags);
                buf = kmap_atomic(page);
 
                /* do the actual data transfer */
@@ -878,7 +878,7 @@ next_sg:
                                                                count, rw);
 
                kunmap_atomic(buf);
-               local_irq_restore(flags);
+               local_irq_restore_nort(flags);
        } else {
                buf = page_address(page);
                consumed = ap->ops->sff_data_xfer(dev,  buf + offset,
index 4b5cd3a..8c93ee1 100644 (file)
@@ -118,12 +118,20 @@ ssize_t zcomp_available_show(const char *comp, char *buf)
 
 struct zcomp_strm *zcomp_stream_get(struct zcomp *comp)
 {
-       return *get_cpu_ptr(comp->stream);
+       struct zcomp_strm *zstrm;
+
+       zstrm = *get_local_ptr(comp->stream);
+       spin_lock(&zstrm->zcomp_lock);
+       return zstrm;
 }
 
 void zcomp_stream_put(struct zcomp *comp)
 {
-       put_cpu_ptr(comp->stream);
+       struct zcomp_strm *zstrm;
+
+       zstrm = *this_cpu_ptr(comp->stream);
+       spin_unlock(&zstrm->zcomp_lock);
+       put_local_ptr(zstrm);
 }
 
 int zcomp_compress(struct zcomp_strm *zstrm,
@@ -174,6 +182,7 @@ static int __zcomp_cpu_notifier(struct zcomp *comp,
                        pr_err("Can't allocate a compression stream\n");
                        return NOTIFY_BAD;
                }
+               spin_lock_init(&zstrm->zcomp_lock);
                *per_cpu_ptr(comp->stream, cpu) = zstrm;
                break;
        case CPU_DEAD:
index 478cac2..f7a6efd 100644 (file)
@@ -14,6 +14,7 @@ struct zcomp_strm {
        /* compression/decompression buffer */
        void *buffer;
        struct crypto_comp *tfm;
+       spinlock_t zcomp_lock;
 };
 
 /* dynamic per-device compression frontend */
index 5864801..d9f34a4 100644 (file)
@@ -528,6 +528,8 @@ static struct zram_meta *zram_meta_alloc(char *pool_name, u64 disksize)
                goto out_error;
        }
 
+       zram_meta_init_table_locks(meta, disksize);
+
        return meta;
 
 out_error:
@@ -575,28 +577,28 @@ static int zram_decompress_page(struct zram *zram, char *mem, u32 index)
        struct zram_meta *meta = zram->meta;
        unsigned long handle;
        unsigned int size;
+       struct zcomp_strm *zstrm;
 
-       bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
+       zram_lock_table(&meta->table[index]);
        handle = meta->table[index].handle;
        size = zram_get_obj_size(meta, index);
 
        if (!handle || zram_test_flag(meta, index, ZRAM_ZERO)) {
-               bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
+               zram_unlock_table(&meta->table[index]);
                memset(mem, 0, PAGE_SIZE);
                return 0;
        }
 
+       zstrm = zcomp_stream_get(zram->comp);
        cmem = zs_map_object(meta->mem_pool, handle, ZS_MM_RO);
        if (size == PAGE_SIZE) {
                memcpy(mem, cmem, PAGE_SIZE);
        } else {
-               struct zcomp_strm *zstrm = zcomp_stream_get(zram->comp);
-
                ret = zcomp_decompress(zstrm, cmem, size, mem);
-               zcomp_stream_put(zram->comp);
        }
        zs_unmap_object(meta->mem_pool, handle);
-       bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
+       zcomp_stream_put(zram->comp);
+       zram_unlock_table(&meta->table[index]);
 
        /* Should NEVER happen. Return bio error if it does. */
        if (unlikely(ret)) {
@@ -616,14 +618,14 @@ static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec,
        struct zram_meta *meta = zram->meta;
        page = bvec->bv_page;
 
-       bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
+       zram_lock_table(&meta->table[index]);
        if (unlikely(!meta->table[index].handle) ||
                        zram_test_flag(meta, index, ZRAM_ZERO)) {
-               bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
+               zram_unlock_table(&meta->table[index]);
                handle_zero_page(bvec);
                return 0;
        }
-       bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
+       zram_unlock_table(&meta->table[index]);
 
        if (is_partial_io(bvec))
                /* Use  a temporary buffer to decompress the page */
@@ -700,10 +702,10 @@ compress_again:
                if (user_mem)
                        kunmap_atomic(user_mem);
                /* Free memory associated with this sector now. */
-               bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
+               zram_lock_table(&meta->table[index]);
                zram_free_page(zram, index);
                zram_set_flag(meta, index, ZRAM_ZERO);
-               bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
+               zram_unlock_table(&meta->table[index]);
 
                atomic64_inc(&zram->stats.zero_pages);
                ret = 0;
@@ -803,12 +805,12 @@ compress_again:
         * Free memory associated with this sector
         * before overwriting unused sectors.
         */
-       bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
+       zram_lock_table(&meta->table[index]);
        zram_free_page(zram, index);
 
        meta->table[index].handle = handle;
        zram_set_obj_size(meta, index, clen);
-       bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
+       zram_unlock_table(&meta->table[index]);
 
        /* Update stats */
        atomic64_add(clen, &zram->stats.compr_data_size);
@@ -851,9 +853,9 @@ static void zram_bio_discard(struct zram *zram, u32 index,
        }
 
        while (n >= PAGE_SIZE) {
-               bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
+               zram_lock_table(&meta->table[index]);
                zram_free_page(zram, index);
-               bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
+               zram_unlock_table(&meta->table[index]);
                atomic64_inc(&zram->stats.notify_free);
                index++;
                n -= PAGE_SIZE;
@@ -982,9 +984,9 @@ static void zram_slot_free_notify(struct block_device *bdev,
        zram = bdev->bd_disk->private_data;
        meta = zram->meta;
 
-       bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
+       zram_lock_table(&meta->table[index]);
        zram_free_page(zram, index);
-       bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
+       zram_unlock_table(&meta->table[index]);
        atomic64_inc(&zram->stats.notify_free);
 }
 
index 6d2475a..87278e8 100644 (file)
@@ -72,6 +72,9 @@ enum zram_pageflags {
 struct zram_table_entry {
        unsigned long handle;
        unsigned long value;
+#ifdef CONFIG_PREEMPT_RT_BASE
+       spinlock_t lock;
+#endif
 };
 
 struct zram_stats {
@@ -119,4 +122,42 @@ struct zram {
         */
        bool claim; /* Protected by bdev->bd_mutex */
 };
+
+#ifndef CONFIG_PREEMPT_RT_BASE
+static inline void zram_lock_table(struct zram_table_entry *table)
+{
+       bit_spin_lock(ZRAM_ACCESS, &table->value);
+}
+
+static inline void zram_unlock_table(struct zram_table_entry *table)
+{
+       bit_spin_unlock(ZRAM_ACCESS, &table->value);
+}
+
+static inline void zram_meta_init_table_locks(struct zram_meta *meta, u64 disksize) { }
+#else /* CONFIG_PREEMPT_RT_BASE */
+static inline void zram_lock_table(struct zram_table_entry *table)
+{
+       spin_lock(&table->lock);
+       __set_bit(ZRAM_ACCESS, &table->value);
+}
+
+static inline void zram_unlock_table(struct zram_table_entry *table)
+{
+       __clear_bit(ZRAM_ACCESS, &table->value);
+       spin_unlock(&table->lock);
+}
+
+static inline void zram_meta_init_table_locks(struct zram_meta *meta, u64 disksize)
+{
+        size_t num_pages = disksize >> PAGE_SHIFT;
+        size_t index;
+
+        for (index = 0; index < num_pages; index++) {
+               spinlock_t *lock = &meta->table[index].lock;
+               spin_lock_init(lock);
+        }
+}
+#endif /* CONFIG_PREEMPT_RT_BASE */
+
 #endif
index c417aa1..2c0fb09 100644 (file)
 #include <linux/syscalls.h>
 #include <linux/completion.h>
 #include <linux/uuid.h>
+#include <linux/locallock.h>
 #include <crypto/chacha20.h>
 
 #include <asm/processor.h>
@@ -1087,8 +1088,6 @@ static void add_timer_randomness(struct timer_rand_state *state, unsigned num)
        } sample;
        long delta, delta2, delta3;
 
-       preempt_disable();
-
        sample.jiffies = jiffies;
        sample.cycles = random_get_entropy();
        sample.num = num;
@@ -1129,7 +1128,6 @@ static void add_timer_randomness(struct timer_rand_state *state, unsigned num)
                 */
                credit_entropy_bits(r, min_t(int, fls(delta>>1), 11));
        }
-       preempt_enable();
 }
 
 void add_input_randomness(unsigned int type, unsigned int code,
@@ -1186,28 +1184,27 @@ static __u32 get_reg(struct fast_pool *f, struct pt_regs *regs)
        return *ptr;
 }
 
-void add_interrupt_randomness(int irq, int irq_flags)
+void add_interrupt_randomness(int irq, int irq_flags, __u64 ip)
 {
        struct entropy_store    *r;
        struct fast_pool        *fast_pool = this_cpu_ptr(&irq_randomness);
-       struct pt_regs          *regs = get_irq_regs();
        unsigned long           now = jiffies;
        cycles_t                cycles = random_get_entropy();
        __u32                   c_high, j_high;
-       __u64                   ip;
        unsigned long           seed;
        int                     credit = 0;
 
        if (cycles == 0)
-               cycles = get_reg(fast_pool, regs);
+               cycles = get_reg(fast_pool, NULL);
        c_high = (sizeof(cycles) > 4) ? cycles >> 32 : 0;
        j_high = (sizeof(now) > 4) ? now >> 32 : 0;
        fast_pool->pool[0] ^= cycles ^ j_high ^ irq;
        fast_pool->pool[1] ^= now ^ c_high;
-       ip = regs ? instruction_pointer(regs) : _RET_IP_;
+       if (!ip)
+               ip = _RET_IP_;
        fast_pool->pool[2] ^= ip;
        fast_pool->pool[3] ^= (sizeof(ip) > 4) ? ip >> 32 :
-               get_reg(fast_pool, regs);
+               get_reg(fast_pool, NULL);
 
        fast_mix(fast_pool);
        add_interrupt_bench(cycles);
@@ -1669,7 +1666,7 @@ void get_random_bytes_arch(void *buf, int nbytes)
 
                if (!arch_get_random_long(&v))
                        break;
-               
+
                memcpy(p, &v, chunk);
                p += chunk;
                nbytes -= chunk;
@@ -2123,18 +2120,22 @@ struct batched_entropy {
  * the goal of being quite fast and not depleting entropy.
  */
 static DEFINE_PER_CPU(struct batched_entropy, batched_entropy_long);
+static DEFINE_LOCAL_IRQ_LOCK(batched_entropy_long_lock);
 unsigned long get_random_long(void)
 {
        unsigned long ret;
        struct batched_entropy *batch;
 
-       batch = &get_cpu_var(batched_entropy_long);
+       if (arch_get_random_long(&ret))
+               return ret;
+
+       batch = &get_locked_var(batched_entropy_long_lock, batched_entropy_long);
        if (batch->position % ARRAY_SIZE(batch->entropy_long) == 0) {
                extract_crng((u8 *)batch->entropy_long);
                batch->position = 0;
        }
        ret = batch->entropy_long[batch->position++];
-       put_cpu_var(batched_entropy_long);
+       put_locked_var(batched_entropy_long_lock, batched_entropy_long);
        return ret;
 }
 EXPORT_SYMBOL(get_random_long);
@@ -2146,18 +2147,23 @@ unsigned int get_random_int(void)
 }
 #else
 static DEFINE_PER_CPU(struct batched_entropy, batched_entropy_int);
+static DEFINE_LOCAL_IRQ_LOCK(batched_entropy_int_lock);
+
 unsigned int get_random_int(void)
 {
        unsigned int ret;
        struct batched_entropy *batch;
 
-       batch = &get_cpu_var(batched_entropy_int);
+       if (arch_get_random_int(&ret))
+               return ret;
+
+       batch = &get_locked_var(batched_entropy_int_lock, batched_entropy_int);
        if (batch->position % ARRAY_SIZE(batch->entropy_int) == 0) {
                extract_crng((u8 *)batch->entropy_int);
                batch->position = 0;
        }
        ret = batch->entropy_int[batch->position++];
-       put_cpu_var(batched_entropy_int);
+       put_locked_var(batched_entropy_int_lock, batched_entropy_int);
        return ret;
 }
 #endif
index 06173d2..b170763 100644 (file)
@@ -50,6 +50,31 @@ static inline struct tpm_tis_tcg_phy *to_tpm_tis_tcg_phy(struct tpm_tis_data *da
        return container_of(data, struct tpm_tis_tcg_phy, priv);
 }
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+/*
+ * Flushes previous write operations to chip so that a subsequent
+ * ioread*()s won't stall a cpu.
+ */
+static inline void tpm_tis_flush(void __iomem *iobase)
+{
+       ioread8(iobase + TPM_ACCESS(0));
+}
+#else
+#define tpm_tis_flush(iobase) do { } while (0)
+#endif
+
+static inline void tpm_tis_iowrite8(u8 b, void __iomem *iobase, u32 addr)
+{
+       iowrite8(b, iobase + addr);
+       tpm_tis_flush(iobase);
+}
+
+static inline void tpm_tis_iowrite32(u32 b, void __iomem *iobase, u32 addr)
+{
+       iowrite32(b, iobase + addr);
+       tpm_tis_flush(iobase);
+}
+
 static bool interrupts = true;
 module_param(interrupts, bool, 0444);
 MODULE_PARM_DESC(interrupts, "Enable interrupts");
@@ -103,7 +128,7 @@ static int tpm_tcg_write_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
        struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 
        while (len--)
-               iowrite8(*value++, phy->iobase + addr);
+               tpm_tis_iowrite8(*value++, phy->iobase, addr);
        return 0;
 }
 
@@ -127,7 +152,7 @@ static int tpm_tcg_write32(struct tpm_tis_data *data, u32 addr, u32 value)
 {
        struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 
-       iowrite32(value, phy->iobase + addr);
+       tpm_tis_iowrite32(value, phy->iobase, addr);
        return 0;
 }
 
index 4da2af9..5b6f57f 100644 (file)
@@ -23,8 +23,7 @@
  *     this 32 bit free-running counter. the second channel is not used.
  *
  *   - The third channel may be used to provide a 16-bit clockevent
- *     source, used in either periodic or oneshot mode.  This runs
- *     at 32 KiHZ, and can handle delays of up to two seconds.
+ *     source, used in either periodic or oneshot mode.
  *
  * A boot clocksource and clockevent source are also currently needed,
  * unless the relevant platforms (ARM/AT91, AVR32/AT32) are changed so
@@ -74,6 +73,8 @@ static struct clocksource clksrc = {
 struct tc_clkevt_device {
        struct clock_event_device       clkevt;
        struct clk                      *clk;
+       bool                            clk_enabled;
+       u32                             freq;
        void __iomem                    *regs;
 };
 
@@ -82,15 +83,26 @@ static struct tc_clkevt_device *to_tc_clkevt(struct clock_event_device *clkevt)
        return container_of(clkevt, struct tc_clkevt_device, clkevt);
 }
 
-/* For now, we always use the 32K clock ... this optimizes for NO_HZ,
- * because using one of the divided clocks would usually mean the
- * tick rate can never be less than several dozen Hz (vs 0.5 Hz).
- *
- * A divided clock could be good for high resolution timers, since
- * 30.5 usec resolution can seem "low".
- */
 static u32 timer_clock;
 
+static void tc_clk_disable(struct clock_event_device *d)
+{
+       struct tc_clkevt_device *tcd = to_tc_clkevt(d);
+
+       clk_disable(tcd->clk);
+       tcd->clk_enabled = false;
+}
+
+static void tc_clk_enable(struct clock_event_device *d)
+{
+       struct tc_clkevt_device *tcd = to_tc_clkevt(d);
+
+       if (tcd->clk_enabled)
+               return;
+       clk_enable(tcd->clk);
+       tcd->clk_enabled = true;
+}
+
 static int tc_shutdown(struct clock_event_device *d)
 {
        struct tc_clkevt_device *tcd = to_tc_clkevt(d);
@@ -98,8 +110,14 @@ static int tc_shutdown(struct clock_event_device *d)
 
        __raw_writel(0xff, regs + ATMEL_TC_REG(2, IDR));
        __raw_writel(ATMEL_TC_CLKDIS, regs + ATMEL_TC_REG(2, CCR));
+       return 0;
+}
+
+static int tc_shutdown_clk_off(struct clock_event_device *d)
+{
+       tc_shutdown(d);
        if (!clockevent_state_detached(d))
-               clk_disable(tcd->clk);
+               tc_clk_disable(d);
 
        return 0;
 }
@@ -112,9 +130,9 @@ static int tc_set_oneshot(struct clock_event_device *d)
        if (clockevent_state_oneshot(d) || clockevent_state_periodic(d))
                tc_shutdown(d);
 
-       clk_enable(tcd->clk);
+       tc_clk_enable(d);
 
-       /* slow clock, count up to RC, then irq and stop */
+       /* count up to RC, then irq and stop */
        __raw_writel(timer_clock | ATMEL_TC_CPCSTOP | ATMEL_TC_WAVE |
                     ATMEL_TC_WAVESEL_UP_AUTO, regs + ATMEL_TC_REG(2, CMR));
        __raw_writel(ATMEL_TC_CPCS, regs + ATMEL_TC_REG(2, IER));
@@ -134,12 +152,12 @@ static int tc_set_periodic(struct clock_event_device *d)
        /* By not making the gentime core emulate periodic mode on top
         * of oneshot, we get lower overhead and improved accuracy.
         */
-       clk_enable(tcd->clk);
+       tc_clk_enable(d);
 
-       /* slow clock, count up to RC, then irq and restart */
+       /* count up to RC, then irq and restart */
        __raw_writel(timer_clock | ATMEL_TC_WAVE | ATMEL_TC_WAVESEL_UP_AUTO,
                     regs + ATMEL_TC_REG(2, CMR));
-       __raw_writel((32768 + HZ / 2) / HZ, tcaddr + ATMEL_TC_REG(2, RC));
+       __raw_writel((tcd->freq + HZ / 2) / HZ, tcaddr + ATMEL_TC_REG(2, RC));
 
        /* Enable clock and interrupts on RC compare */
        __raw_writel(ATMEL_TC_CPCS, regs + ATMEL_TC_REG(2, IER));
@@ -166,9 +184,13 @@ static struct tc_clkevt_device clkevt = {
                .features               = CLOCK_EVT_FEAT_PERIODIC |
                                          CLOCK_EVT_FEAT_ONESHOT,
                /* Should be lower than at91rm9200's system timer */
+#ifdef CONFIG_ATMEL_TCB_CLKSRC_USE_SLOW_CLOCK
                .rating                 = 125,
+#else
+               .rating                 = 200,
+#endif
                .set_next_event         = tc_next_event,
-               .set_state_shutdown     = tc_shutdown,
+               .set_state_shutdown     = tc_shutdown_clk_off,
                .set_state_periodic     = tc_set_periodic,
                .set_state_oneshot      = tc_set_oneshot,
        },
@@ -188,8 +210,9 @@ static irqreturn_t ch2_irq(int irq, void *handle)
        return IRQ_NONE;
 }
 
-static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx)
+static int __init setup_clkevents(struct atmel_tc *tc, int divisor_idx)
 {
+       unsigned divisor = atmel_tc_divisors[divisor_idx];
        int ret;
        struct clk *t2_clk = tc->clk[2];
        int irq = tc->irq[2];
@@ -210,7 +233,11 @@ static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx)
        clkevt.regs = tc->regs;
        clkevt.clk = t2_clk;
 
-       timer_clock = clk32k_divisor_idx;
+       timer_clock = divisor_idx;
+       if (!divisor)
+               clkevt.freq = 32768;
+       else
+               clkevt.freq = clk_get_rate(t2_clk) / divisor;
 
        clkevt.clkevt.cpumask = cpumask_of(0);
 
@@ -221,7 +248,7 @@ static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx)
                return ret;
        }
 
-       clockevents_config_and_register(&clkevt.clkevt, 32768, 1, 0xffff);
+       clockevents_config_and_register(&clkevt.clkevt, clkevt.freq, 1, 0xffff);
 
        return ret;
 }
@@ -358,7 +385,11 @@ static int __init tcb_clksrc_init(void)
                goto err_disable_t1;
 
        /* channel 2:  periodic and oneshot timer support */
+#ifdef CONFIG_ATMEL_TCB_CLKSRC_USE_SLOW_CLOCK
        ret = setup_clkevents(tc, clk32k_divisor_idx);
+#else
+       ret = setup_clkevents(tc, best_divisor_idx);
+#endif
        if (ret)
                goto err_unregister_clksrc;
 
index 6555821..9328884 100644 (file)
@@ -46,6 +46,7 @@ struct pit_data {
        u32             cycle;
        u32             cnt;
        unsigned int    irq;
+       bool            irq_requested;
        struct clk      *mck;
 };
 
@@ -96,15 +97,29 @@ static int pit_clkevt_shutdown(struct clock_event_device *dev)
 
        /* disable irq, leaving the clocksource active */
        pit_write(data->base, AT91_PIT_MR, (data->cycle - 1) | AT91_PIT_PITEN);
+       if (data->irq_requested) {
+               free_irq(data->irq, data);
+               data->irq_requested = false;
+       }
        return 0;
 }
 
+static irqreturn_t at91sam926x_pit_interrupt(int irq, void *dev_id);
 /*
  * Clockevent device:  interrupts every 1/HZ (== pit_cycles * MCK/16)
  */
 static int pit_clkevt_set_periodic(struct clock_event_device *dev)
 {
        struct pit_data *data = clkevt_to_pit_data(dev);
+       int ret;
+
+       ret = request_irq(data->irq, at91sam926x_pit_interrupt,
+                         IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
+                         "at91_tick", data);
+       if (ret)
+               panic(pr_fmt("Unable to setup IRQ\n"));
+
+       data->irq_requested = true;
 
        /* update clocksource counter */
        data->cnt += data->cycle * PIT_PICNT(pit_read(data->base, AT91_PIT_PIVR));
@@ -230,15 +245,6 @@ static int __init at91sam926x_pit_dt_init(struct device_node *node)
                return ret;
        }
 
-       /* Set up irq handler */
-       ret = request_irq(data->irq, at91sam926x_pit_interrupt,
-                         IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
-                         "at91_tick", data);
-       if (ret) {
-               pr_err("Unable to setup IRQ\n");
-               return ret;
-       }
-
        /* Set up and register clockevents */
        data->clkevt.name = "pit";
        data->clkevt.features = CLOCK_EVT_FEAT_PERIODIC;
index e90ab5b..9e12408 100644 (file)
@@ -115,18 +115,29 @@ static void clkdev32k_disable_and_flush_irq(void)
        last_crtr = read_CRTR();
 }
 
+static int atmel_st_irq;
+
 static int clkevt32k_shutdown(struct clock_event_device *evt)
 {
        clkdev32k_disable_and_flush_irq();
        irqmask = 0;
        regmap_write(regmap_st, AT91_ST_IER, irqmask);
+       free_irq(atmel_st_irq, regmap_st);
        return 0;
 }
 
 static int clkevt32k_set_oneshot(struct clock_event_device *dev)
 {
+       int ret;
+
        clkdev32k_disable_and_flush_irq();
 
+       ret = request_irq(atmel_st_irq, at91rm9200_timer_interrupt,
+                         IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
+                         "at91_tick", regmap_st);
+       if (ret)
+               panic(pr_fmt("Unable to setup IRQ\n"));
+
        /*
         * ALM for oneshot irqs, set by next_event()
         * before 32 seconds have passed.
@@ -139,8 +150,16 @@ static int clkevt32k_set_oneshot(struct clock_event_device *dev)
 
 static int clkevt32k_set_periodic(struct clock_event_device *dev)
 {
+       int ret;
+
        clkdev32k_disable_and_flush_irq();
 
+       ret = request_irq(atmel_st_irq, at91rm9200_timer_interrupt,
+                         IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
+                         "at91_tick", regmap_st);
+       if (ret)
+               panic(pr_fmt("Unable to setup IRQ\n"));
+
        /* PIT for periodic irqs; fixed rate of 1/HZ */
        irqmask = AT91_ST_PITS;
        regmap_write(regmap_st, AT91_ST_PIMR, timer_latch);
@@ -198,7 +217,7 @@ static int __init atmel_st_timer_init(struct device_node *node)
 {
        struct clk *sclk;
        unsigned int sclk_rate, val;
-       int irq, ret;
+       int ret;
 
        regmap_st = syscon_node_to_regmap(node);
        if (IS_ERR(regmap_st)) {
@@ -212,21 +231,12 @@ static int __init atmel_st_timer_init(struct device_node *node)
        regmap_read(regmap_st, AT91_ST_SR, &val);
 
        /* Get the interrupts property */
-       irq  = irq_of_parse_and_map(node, 0);
-       if (!irq) {
+       atmel_st_irq  = irq_of_parse_and_map(node, 0);
+       if (!atmel_st_irq) {
                pr_err("Unable to get IRQ from DT\n");
                return -EINVAL;
        }
 
-       /* Make IRQs happen for the system timer */
-       ret = request_irq(irq, at91rm9200_timer_interrupt,
-                         IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
-                         "at91_tick", regmap_st);
-       if (ret) {
-               pr_err("Unable to setup IRQ\n");
-               return ret;
-       }
-
        sclk = of_clk_get(node, 0);
        if (IS_ERR(sclk)) {
                pr_err("Unable to get slow clock\n");
index a782ce8..19d2659 100644 (file)
@@ -32,6 +32,7 @@
 #include <linux/pid_namespace.h>
 
 #include <linux/cn_proc.h>
+#include <linux/locallock.h>
 
 /*
  * Size of a cn_msg followed by a proc_event structure.  Since the
@@ -54,10 +55,11 @@ static struct cb_id cn_proc_event_id = { CN_IDX_PROC, CN_VAL_PROC };
 
 /* proc_event_counts is used as the sequence number of the netlink message */
 static DEFINE_PER_CPU(__u32, proc_event_counts) = { 0 };
+static DEFINE_LOCAL_IRQ_LOCK(send_msg_lock);
 
 static inline void send_msg(struct cn_msg *msg)
 {
-       preempt_disable();
+       local_lock(send_msg_lock);
 
        msg->seq = __this_cpu_inc_return(proc_event_counts) - 1;
        ((struct proc_event *)msg->data)->cpu = smp_processor_id();
@@ -70,7 +72,7 @@ static inline void send_msg(struct cn_msg *msg)
         */
        cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_NOWAIT);
 
-       preempt_enable();
+       local_unlock(send_msg_lock);
 }
 
 void proc_fork_connector(struct task_struct *task)
index adbd1de..1fac507 100644 (file)
@@ -124,7 +124,7 @@ config X86_POWERNOW_K7_ACPI
 
 config X86_POWERNOW_K8
        tristate "AMD Opteron/Athlon64 PowerNow!"
-       depends on ACPI && ACPI_PROCESSOR && X86_ACPI_CPUFREQ
+       depends on ACPI && ACPI_PROCESSOR && X86_ACPI_CPUFREQ && !PREEMPT_RT_BASE
        help
          This adds the CPUFreq driver for K8/early Opteron/Athlon64 processors.
          Support for K10 and newer processors is now in acpi-cpufreq.
index 4548d89..4a7df7d 100644 (file)
@@ -1531,7 +1531,9 @@ execbuf_submit(struct i915_execbuffer_params *params,
        if (ret)
                return ret;
 
+#ifndef CONFIG_PREEMPT_RT_BASE
        trace_i915_gem_ring_dispatch(params->request, params->dispatch_flags);
+#endif
 
        i915_gem_execbuffer_move_to_active(vmas, params->request);
 
index 755d788..97fb03d 100644 (file)
@@ -40,7 +40,7 @@ static bool mutex_is_locked_by(struct mutex *mutex, struct task_struct *task)
        if (!mutex_is_locked(mutex))
                return false;
 
-#if defined(CONFIG_DEBUG_MUTEXES) || defined(CONFIG_MUTEX_SPIN_ON_OWNER)
+#if (defined(CONFIG_DEBUG_MUTEXES) || defined(CONFIG_MUTEX_SPIN_ON_OWNER)) && !defined(CONFIG_PREEMPT_RT_BASE)
        return mutex->owner == task;
 #else
        /* Since UP may be pre-empted, we cannot assume that we own the lock */
index 685247c..df3eefd 100644 (file)
@@ -812,6 +812,7 @@ static int i915_get_crtc_scanoutpos(struct drm_device *dev, unsigned int pipe,
        spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
 
        /* preempt_disable_rt() should go right here in PREEMPT_RT patchset. */
+       preempt_disable_rt();
 
        /* Get optional system timestamp before query. */
        if (stime)
@@ -863,6 +864,7 @@ static int i915_get_crtc_scanoutpos(struct drm_device *dev, unsigned int pipe,
                *etime = ktime_get();
 
        /* preempt_enable_rt() should go right here in PREEMPT_RT patchset. */
+       preempt_enable_rt();
 
        spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
 
index d915877..7cbb799 100644 (file)
@@ -12139,7 +12139,7 @@ void intel_check_page_flip(struct drm_i915_private *dev_priv, int pipe)
        struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
        struct intel_flip_work *work;
 
-       WARN_ON(!in_interrupt());
+       WARN_ON_NONRT(!in_interrupt());
 
        if (crtc == NULL)
                return;
index 64f4e2e..aebf1e9 100644 (file)
@@ -35,6 +35,7 @@
 #include <drm/drm_rect.h>
 #include <drm/drm_atomic.h>
 #include <drm/drm_plane_helper.h>
+#include <linux/locallock.h>
 #include "intel_drv.h"
 #include "intel_frontbuffer.h"
 #include <drm/i915_drm.h>
@@ -65,6 +66,8 @@ int intel_usecs_to_scanlines(const struct drm_display_mode *adjusted_mode,
                            1000 * adjusted_mode->crtc_htotal);
 }
 
+static DEFINE_LOCAL_IRQ_LOCK(pipe_update_lock);
+
 /**
  * intel_pipe_update_start() - start update of a set of display registers
  * @crtc: the crtc of which the registers are going to be updated
@@ -98,7 +101,7 @@ void intel_pipe_update_start(struct intel_crtc *crtc)
        min = vblank_start - intel_usecs_to_scanlines(adjusted_mode, 100);
        max = vblank_start - 1;
 
-       local_irq_disable();
+       local_lock_irq(pipe_update_lock);
 
        if (min <= 0 || max <= 0)
                return;
@@ -128,11 +131,11 @@ void intel_pipe_update_start(struct intel_crtc *crtc)
                        break;
                }
 
-               local_irq_enable();
+               local_unlock_irq(pipe_update_lock);
 
                timeout = schedule_timeout(timeout);
 
-               local_irq_disable();
+               local_lock_irq(pipe_update_lock);
        }
 
        finish_wait(wq, &wait);
@@ -202,7 +205,7 @@ void intel_pipe_update_end(struct intel_crtc *crtc, struct intel_flip_work *work
                crtc->base.state->event = NULL;
        }
 
-       local_irq_enable();
+       local_unlock_irq(pipe_update_lock);
 
        if (crtc->debug.start_vbl_count &&
            crtc->debug.start_vbl_count != end_vbl_count) {
index 192b2d3..d5372a2 100644 (file)
@@ -23,7 +23,7 @@ static bool mutex_is_locked_by(struct mutex *mutex, struct task_struct *task)
        if (!mutex_is_locked(mutex))
                return false;
 
-#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_MUTEXES)
+#if (defined(CONFIG_SMP) || defined(CONFIG_DEBUG_MUTEXES)) && !defined(CONFIG_PREEMPT_RT_BASE)
        return mutex->owner == task;
 #else
        /* Since UP may be pre-empted, we cannot assume that we own the lock */
index 99e2380..dc74c53 100644 (file)
@@ -1855,6 +1855,7 @@ int radeon_get_crtc_scanoutpos(struct drm_device *dev, unsigned int pipe,
        struct radeon_device *rdev = dev->dev_private;
 
        /* preempt_disable_rt() should go right here in PREEMPT_RT patchset. */
+       preempt_disable_rt();
 
        /* Get optional system timestamp before query. */
        if (stime)
@@ -1947,6 +1948,7 @@ int radeon_get_crtc_scanoutpos(struct drm_device *dev, unsigned int pipe,
                *etime = ktime_get();
 
        /* preempt_enable_rt() should go right here in PREEMPT_RT patchset. */
+       preempt_enable_rt();
 
        /* Decode into vertical and horizontal scanout position. */
        *vpos = position & 0x1fff;
index 9a0d0d0..ca93cfa 100644 (file)
@@ -43,6 +43,7 @@
 #include <linux/kdebug.h>
 #include <linux/efi.h>
 #include <linux/random.h>
+#include <asm/irq_regs.h>
 #include "hyperv_vmbus.h"
 
 static struct acpi_device  *hv_acpi_dev;
@@ -781,6 +782,8 @@ static void vmbus_isr(void)
        void *page_addr;
        struct hv_message *msg;
        union hv_synic_event_flags *event;
+       struct pt_regs *regs = get_irq_regs();
+       u64 ip = regs ? instruction_pointer(regs) : 0;
        bool handled = false;
 
        page_addr = hv_context.synic_event_page[cpu];
@@ -828,7 +831,7 @@ static void vmbus_isr(void)
                        tasklet_schedule(hv_context.msg_dpc[cpu]);
        }
 
-       add_interrupt_randomness(HYPERVISOR_CALLBACK_VECTOR, 0);
+       add_interrupt_randomness(HYPERVISOR_CALLBACK_VECTOR, 0, ip);
 }
 
 
index 36f76e2..394f142 100644 (file)
@@ -234,7 +234,7 @@ static int init_chipset_ali15x3(struct pci_dev *dev)
 
        isa_dev = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533, NULL);
 
-       local_irq_save(flags);
+       local_irq_save_nort(flags);
 
        if (m5229_revision < 0xC2) {
                /*
@@ -325,7 +325,7 @@ out:
        }
        pci_dev_put(north);
        pci_dev_put(isa_dev);
-       local_irq_restore(flags);
+       local_irq_restore_nort(flags);
        return 0;
 }
 
index 0ceae5c..c212e85 100644 (file)
@@ -1236,7 +1236,7 @@ static int init_dma_hpt366(ide_hwif_t *hwif,
 
        dma_old = inb(base + 2);
 
-       local_irq_save(flags);
+       local_irq_save_nort(flags);
 
        dma_new = dma_old;
        pci_read_config_byte(dev, hwif->channel ? 0x4b : 0x43, &masterdma);
@@ -1247,7 +1247,7 @@ static int init_dma_hpt366(ide_hwif_t *hwif,
        if (dma_new != dma_old)
                outb(dma_new, base + 2);
 
-       local_irq_restore(flags);
+       local_irq_restore_nort(flags);
 
        printk(KERN_INFO "    %s: BM-DMA at 0x%04lx-0x%04lx\n",
                         hwif->name, base, base + 7);
index 1976397..4169433 100644 (file)
@@ -175,7 +175,7 @@ void ide_input_data(ide_drive_t *drive, struct ide_cmd *cmd, void *buf,
                unsigned long uninitialized_var(flags);
 
                if ((io_32bit & 2) && !mmio) {
-                       local_irq_save(flags);
+                       local_irq_save_nort(flags);
                        ata_vlb_sync(io_ports->nsect_addr);
                }
 
@@ -186,7 +186,7 @@ void ide_input_data(ide_drive_t *drive, struct ide_cmd *cmd, void *buf,
                        insl(data_addr, buf, words);
 
                if ((io_32bit & 2) && !mmio)
-                       local_irq_restore(flags);
+                       local_irq_restore_nort(flags);
 
                if (((len + 1) & 3) < 2)
                        return;
@@ -219,7 +219,7 @@ void ide_output_data(ide_drive_t *drive, struct ide_cmd *cmd, void *buf,
                unsigned long uninitialized_var(flags);
 
                if ((io_32bit & 2) && !mmio) {
-                       local_irq_save(flags);
+                       local_irq_save_nort(flags);
                        ata_vlb_sync(io_ports->nsect_addr);
                }
 
@@ -230,7 +230,7 @@ void ide_output_data(ide_drive_t *drive, struct ide_cmd *cmd, void *buf,
                        outsl(data_addr, buf, words);
 
                if ((io_32bit & 2) && !mmio)
-                       local_irq_restore(flags);
+                       local_irq_restore_nort(flags);
 
                if (((len + 1) & 3) < 2)
                        return;
index 669ea1e..e12e43e 100644 (file)
@@ -659,7 +659,7 @@ void ide_timer_expiry (unsigned long data)
                /* disable_irq_nosync ?? */
                disable_irq(hwif->irq);
                /* local CPU only, as if we were handling an interrupt */
-               local_irq_disable();
+               local_irq_disable_nort();
                if (hwif->polling) {
                        startstop = handler(drive);
                } else if (drive_is_ready(drive)) {
index 376f2dc..f014dd1 100644 (file)
@@ -129,12 +129,12 @@ int __ide_wait_stat(ide_drive_t *drive, u8 good, u8 bad,
                                if ((stat & ATA_BUSY) == 0)
                                        break;
 
-                               local_irq_restore(flags);
+                               local_irq_restore_nort(flags);
                                *rstat = stat;
                                return -EBUSY;
                        }
                }
-               local_irq_restore(flags);
+               local_irq_restore_nort(flags);
        }
        /*
         * Allow status to settle, then read it again.
index 0b63fac..4ceba37 100644 (file)
@@ -196,10 +196,10 @@ static void do_identify(ide_drive_t *drive, u8 cmd, u16 *id)
        int bswap = 1;
 
        /* local CPU only; some systems need this */
-       local_irq_save(flags);
+       local_irq_save_nort(flags);
        /* read 512 bytes of id info */
        hwif->tp_ops->input_data(drive, NULL, id, SECTOR_SIZE);
-       local_irq_restore(flags);
+       local_irq_restore_nort(flags);
 
        drive->dev_flags |= IDE_DFLAG_ID_READ;
 #ifdef DEBUG
index a716693..be0568c 100644 (file)
@@ -250,7 +250,7 @@ void ide_pio_bytes(ide_drive_t *drive, struct ide_cmd *cmd,
 
                page_is_high = PageHighMem(page);
                if (page_is_high)
-                       local_irq_save(flags);
+                       local_irq_save_nort(flags);
 
                buf = kmap_atomic(page) + offset;
 
@@ -271,7 +271,7 @@ void ide_pio_bytes(ide_drive_t *drive, struct ide_cmd *cmd,
                kunmap_atomic(buf);
 
                if (page_is_high)
-                       local_irq_restore(flags);
+                       local_irq_restore_nort(flags);
 
                len -= nr_bytes;
        }
@@ -414,7 +414,7 @@ static ide_startstop_t pre_task_out_intr(ide_drive_t *drive,
        }
 
        if ((drive->dev_flags & IDE_DFLAG_UNMASK) == 0)
-               local_irq_disable();
+               local_irq_disable_nort();
 
        ide_set_handler(drive, &task_pio_intr, WAIT_WORSTCASE);
 
index 8f79cae..982e97f 100644 (file)
@@ -904,7 +904,7 @@ void ipoib_mcast_restart_task(struct work_struct *work)
 
        ipoib_dbg_mcast(priv, "restarting multicast task\n");
 
-       local_irq_save(flags);
+       local_irq_save_nort(flags);
        netif_addr_lock(dev);
        spin_lock(&priv->lock);
 
@@ -986,7 +986,7 @@ void ipoib_mcast_restart_task(struct work_struct *work)
 
        spin_unlock(&priv->lock);
        netif_addr_unlock(dev);
-       local_irq_restore(flags);
+       local_irq_restore_nort(flags);
 
        /*
         * make sure the in-flight joins have finished before we attempt
index 4a2a9e3..e970d9a 100644 (file)
@@ -91,13 +91,13 @@ static int gameport_measure_speed(struct gameport *gameport)
        tx = ~0;
 
        for (i = 0; i < 50; i++) {
-               local_irq_save(flags);
+               local_irq_save_nort(flags);
                t1 = ktime_get_ns();
                for (t = 0; t < 50; t++)
                        gameport_read(gameport);
                t2 = ktime_get_ns();
                t3 = ktime_get_ns();
-               local_irq_restore(flags);
+               local_irq_restore_nort(flags);
                udelay(i * 10);
                t = (t2 - t1) - (t3 - t2);
                if (t < tx)
@@ -124,12 +124,12 @@ static int old_gameport_measure_speed(struct gameport *gameport)
        tx = 1 << 30;
 
        for(i = 0; i < 50; i++) {
-               local_irq_save(flags);
+               local_irq_save_nort(flags);
                GET_TIME(t1);
                for (t = 0; t < 50; t++) gameport_read(gameport);
                GET_TIME(t2);
                GET_TIME(t3);
-               local_irq_restore(flags);
+               local_irq_restore_nort(flags);
                udelay(i * 10);
                if ((t = DELTA(t2,t1) - DELTA(t3,t2)) < tx) tx = t;
        }
@@ -148,11 +148,11 @@ static int old_gameport_measure_speed(struct gameport *gameport)
        tx = 1 << 30;
 
        for(i = 0; i < 50; i++) {
-               local_irq_save(flags);
+               local_irq_save_nort(flags);
                t1 = rdtsc();
                for (t = 0; t < 50; t++) gameport_read(gameport);
                t2 = rdtsc();
-               local_irq_restore(flags);
+               local_irq_restore_nort(flags);
                udelay(i * 10);
                if (t2 - t1 < tx) tx = t2 - t1;
        }
index bb0448c..4d84385 100644 (file)
@@ -1953,10 +1953,10 @@ static int __attach_device(struct iommu_dev_data *dev_data,
        int ret;
 
        /*
-        * Must be called with IRQs disabled. Warn here to detect early
-        * when its not.
+        * Must be called with IRQs disabled on a non RT kernel. Warn here to
+        * detect early when its not.
         */
-       WARN_ON(!irqs_disabled());
+       WARN_ON_NONRT(!irqs_disabled());
 
        /* lock domain */
        spin_lock(&domain->lock);
@@ -2126,10 +2126,10 @@ static void __detach_device(struct iommu_dev_data *dev_data)
        struct protection_domain *domain;
 
        /*
-        * Must be called with IRQs disabled. Warn here to detect early
-        * when its not.
+        * Must be called with IRQs disabled on a non RT kernel. Warn here to
+        * detect early when its not.
         */
-       WARN_ON(!irqs_disabled());
+       WARN_ON_NONRT(!irqs_disabled());
 
        if (WARN_ON(!dev_data->domain))
                return;
@@ -2315,7 +2315,7 @@ static void queue_add(struct dma_ops_domain *dma_dom,
        pages     = __roundup_pow_of_two(pages);
        address >>= PAGE_SHIFT;
 
-       queue = get_cpu_ptr(&flush_queue);
+       queue = raw_cpu_ptr(&flush_queue);
        spin_lock_irqsave(&queue->lock, flags);
 
        if (queue->next == FLUSH_QUEUE_SIZE)
@@ -2332,8 +2332,6 @@ static void queue_add(struct dma_ops_domain *dma_dom,
 
        if (atomic_cmpxchg(&queue_timer_on, 0, 1) == 0)
                mod_timer(&queue_timer, jiffies + msecs_to_jiffies(10));
-
-       put_cpu_ptr(&flush_queue);
 }
 
 
index 593a4bf..fa7d784 100644 (file)
@@ -480,7 +480,7 @@ struct deferred_flush_data {
        struct deferred_flush_table *tables;
 };
 
-DEFINE_PER_CPU(struct deferred_flush_data, deferred_flush);
+static DEFINE_PER_CPU(struct deferred_flush_data, deferred_flush);
 
 /* bitmap for indexing intel_iommus */
 static int g_num_of_iommus;
@@ -3742,10 +3742,8 @@ static void add_unmap(struct dmar_domain *dom, unsigned long iova_pfn,
        struct intel_iommu *iommu;
        struct deferred_flush_entry *entry;
        struct deferred_flush_data *flush_data;
-       unsigned int cpuid;
 
-       cpuid = get_cpu();
-       flush_data = per_cpu_ptr(&deferred_flush, cpuid);
+       flush_data = raw_cpu_ptr(&deferred_flush);
 
        /* Flush all CPUs' entries to avoid deferring too much.  If
         * this becomes a bottleneck, can just flush us, and rely on
@@ -3778,8 +3776,6 @@ static void add_unmap(struct dmar_domain *dom, unsigned long iova_pfn,
        }
        flush_data->size++;
        spin_unlock_irqrestore(&flush_data->lock, flags);
-
-       put_cpu();
 }
 
 static void intel_unmap(struct device *dev, dma_addr_t dev_addr, size_t size)
index 99c36a5..92bcc8a 100644 (file)
@@ -22,6 +22,7 @@
 #include <linux/slab.h>
 #include <linux/smp.h>
 #include <linux/bitops.h>
+#include <linux/cpu.h>
 
 static bool iova_rcache_insert(struct iova_domain *iovad,
                               unsigned long pfn,
@@ -420,10 +421,8 @@ retry:
 
                /* Try replenishing IOVAs by flushing rcache. */
                flushed_rcache = true;
-               preempt_disable();
                for_each_online_cpu(cpu)
                        free_cpu_cached_iovas(cpu, iovad);
-               preempt_enable();
                goto retry;
        }
 
@@ -753,7 +752,7 @@ static bool __iova_rcache_insert(struct iova_domain *iovad,
        bool can_insert = false;
        unsigned long flags;
 
-       cpu_rcache = get_cpu_ptr(rcache->cpu_rcaches);
+       cpu_rcache = raw_cpu_ptr(rcache->cpu_rcaches);
        spin_lock_irqsave(&cpu_rcache->lock, flags);
 
        if (!iova_magazine_full(cpu_rcache->loaded)) {
@@ -783,7 +782,6 @@ static bool __iova_rcache_insert(struct iova_domain *iovad,
                iova_magazine_push(cpu_rcache->loaded, iova_pfn);
 
        spin_unlock_irqrestore(&cpu_rcache->lock, flags);
-       put_cpu_ptr(rcache->cpu_rcaches);
 
        if (mag_to_free) {
                iova_magazine_free_pfns(mag_to_free, iovad);
@@ -817,7 +815,7 @@ static unsigned long __iova_rcache_get(struct iova_rcache *rcache,
        bool has_pfn = false;
        unsigned long flags;
 
-       cpu_rcache = get_cpu_ptr(rcache->cpu_rcaches);
+       cpu_rcache = raw_cpu_ptr(rcache->cpu_rcaches);
        spin_lock_irqsave(&cpu_rcache->lock, flags);
 
        if (!iova_magazine_empty(cpu_rcache->loaded)) {
@@ -839,7 +837,6 @@ static unsigned long __iova_rcache_get(struct iova_rcache *rcache,
                iova_pfn = iova_magazine_pop(cpu_rcache->loaded, limit_pfn);
 
        spin_unlock_irqrestore(&cpu_rcache->lock, flags);
-       put_cpu_ptr(rcache->cpu_rcaches);
 
        return iova_pfn;
 }
index 4ec1853..b5e4dd8 100644 (file)
@@ -69,7 +69,7 @@ config LEDS_TRIGGER_BACKLIGHT
 
 config LEDS_TRIGGER_CPU
        bool "LED CPU Trigger"
-       depends on LEDS_TRIGGERS
+       depends on LEDS_TRIGGERS && !PREEMPT_RT_BASE
        help
          This allows LEDs to be controlled by active CPUs. This shows
          the active CPUs across an array of LEDs so you can see which
index 4d20088..98b64ed 100644 (file)
@@ -1,6 +1,7 @@
 
 config BCACHE
        tristate "Block device as cache"
+       depends on !PREEMPT_RT_FULL
        ---help---
        Allows a block device to be used as cache for other devices; uses
        a btree for indexing and the layout is optimized for SSDs.
index ba7c4c6..834ec32 100644 (file)
@@ -842,7 +842,7 @@ static void dm_old_request_fn(struct request_queue *q)
                /* Establish tio->ti before queuing work (map_tio_request) */
                tio->ti = ti;
                kthread_queue_work(&md->kworker, &tio->work);
-               BUG_ON(!irqs_disabled());
+               BUG_ON_NONRT(!irqs_disabled());
        }
 }
 
index 30a853b..51cb06e 100644 (file)
@@ -428,7 +428,7 @@ void raid5_release_stripe(struct stripe_head *sh)
                md_wakeup_thread(conf->mddev->thread);
        return;
 slow_path:
-       local_irq_save(flags);
+       local_irq_save_nort(flags);
        /* we are ok here if STRIPE_ON_RELEASE_LIST is set or not */
        if (atomic_dec_and_lock(&sh->count, &conf->device_lock)) {
                INIT_LIST_HEAD(&list);
@@ -437,7 +437,7 @@ slow_path:
                spin_unlock(&conf->device_lock);
                release_inactive_stripe_list(conf, &list, hash);
        }
-       local_irq_restore(flags);
+       local_irq_restore_nort(flags);
 }
 
 static inline void remove_hash(struct stripe_head *sh)
@@ -1934,8 +1934,9 @@ static void raid_run_ops(struct stripe_head *sh, unsigned long ops_request)
        struct raid5_percpu *percpu;
        unsigned long cpu;
 
-       cpu = get_cpu();
+       cpu = get_cpu_light();
        percpu = per_cpu_ptr(conf->percpu, cpu);
+       spin_lock(&percpu->lock);
        if (test_bit(STRIPE_OP_BIOFILL, &ops_request)) {
                ops_run_biofill(sh);
                overlap_clear++;
@@ -1991,7 +1992,8 @@ static void raid_run_ops(struct stripe_head *sh, unsigned long ops_request)
                        if (test_and_clear_bit(R5_Overlap, &dev->flags))
                                wake_up(&sh->raid_conf->wait_for_overlap);
                }
-       put_cpu();
+       spin_unlock(&percpu->lock);
+       put_cpu_light();
 }
 
 static struct stripe_head *alloc_stripe(struct kmem_cache *sc, gfp_t gfp,
@@ -6436,6 +6438,7 @@ static int raid456_cpu_up_prepare(unsigned int cpu, struct hlist_node *node)
                       __func__, cpu);
                return -ENOMEM;
        }
+       spin_lock_init(&per_cpu_ptr(conf->percpu, cpu)->lock);
        return 0;
 }
 
@@ -6446,7 +6449,6 @@ static int raid5_alloc_percpu(struct r5conf *conf)
        conf->percpu = alloc_percpu(struct raid5_percpu);
        if (!conf->percpu)
                return -ENOMEM;
-
        err = cpuhp_state_add_instance(CPUHP_MD_RAID5_PREPARE, &conf->node);
        if (!err) {
                conf->scribble_disks = max(conf->raid_disks,
index 57ec49f..0739604 100644 (file)
@@ -504,6 +504,7 @@ struct r5conf {
        int                     recovery_disabled;
        /* per cpu variables */
        struct raid5_percpu {
+               spinlock_t      lock;           /* Protection for -RT */
                struct page     *spare_page; /* Used when checking P/Q in raid6 */
                struct flex_array *scribble;   /* space for constructing buffer
                                              * lists and performing address
index 7d3d017..dfc4b62 100644 (file)
@@ -54,6 +54,7 @@ config AD525X_DPOT_SPI
 config ATMEL_TCLIB
        bool "Atmel AT32/AT91 Timer/Counter Library"
        depends on (AVR32 || ARCH_AT91)
+       default y if PREEMPT_RT_FULL
        help
          Select this if you want a library to allocate the Timer/Counter
          blocks found on many Atmel processors.  This facilitates using
@@ -69,8 +70,7 @@ config ATMEL_TCB_CLKSRC
          are combined to make a single 32-bit timer.
 
          When GENERIC_CLOCKEVENTS is defined, the third timer channel
-         may be used as a clock event device supporting oneshot mode
-         (delays of up to two seconds) based on the 32 KiHz clock.
+         may be used as a clock event device supporting oneshot mode.
 
 config ATMEL_TCB_CLKSRC_BLOCK
        int
@@ -84,6 +84,15 @@ config ATMEL_TCB_CLKSRC_BLOCK
          TC can be used for other purposes, such as PWM generation and
          interval timing.
 
+config ATMEL_TCB_CLKSRC_USE_SLOW_CLOCK
+       bool "TC Block use 32 KiHz clock"
+       depends on ATMEL_TCB_CLKSRC
+       default y if !PREEMPT_RT_FULL
+       help
+         Select this to use 32 KiHz base clock rate as TC block clock
+         source for clock events.
+
+
 config DUMMY_IRQ
        tristate "Dummy IRQ handler"
        default n
index df990bb..1a16270 100644 (file)
@@ -1147,15 +1147,12 @@ static irqreturn_t mmci_pio_irq(int irq, void *dev_id)
        struct sg_mapping_iter *sg_miter = &host->sg_miter;
        struct variant_data *variant = host->variant;
        void __iomem *base = host->base;
-       unsigned long flags;
        u32 status;
 
        status = readl(base + MMCISTATUS);
 
        dev_dbg(mmc_dev(host->mmc), "irq1 (pio) %08x\n", status);
 
-       local_irq_save(flags);
-
        do {
                unsigned int remain, len;
                char *buffer;
@@ -1195,8 +1192,6 @@ static irqreturn_t mmci_pio_irq(int irq, void *dev_id)
 
        sg_miter_stop(sg_miter);
 
-       local_irq_restore(flags);
-
        /*
         * If we have less than the fifo 'half-full' threshold to transfer,
         * trigger a PIO interrupt as soon as any data is available.
index 9133e79..63afb92 100644 (file)
@@ -842,9 +842,9 @@ static void poll_vortex(struct net_device *dev)
 {
        struct vortex_private *vp = netdev_priv(dev);
        unsigned long flags;
-       local_irq_save(flags);
+       local_irq_save_nort(flags);
        (vp->full_bus_master_rx ? boomerang_interrupt:vortex_interrupt)(dev->irq,dev);
-       local_irq_restore(flags);
+       local_irq_restore_nort(flags);
 }
 #endif
 
@@ -1910,12 +1910,12 @@ static void vortex_tx_timeout(struct net_device *dev)
                         * Block interrupts because vortex_interrupt does a bare spin_lock()
                         */
                        unsigned long flags;
-                       local_irq_save(flags);
+                       local_irq_save_nort(flags);
                        if (vp->full_bus_master_tx)
                                boomerang_interrupt(dev->irq, dev);
                        else
                                vortex_interrupt(dev->irq, dev);
-                       local_irq_restore(flags);
+                       local_irq_restore_nort(flags);
                }
        }
 
index 570e75e..875aede 100644 (file)
@@ -3169,7 +3169,7 @@ exit:
        }
        mutex_unlock(&_pno_state->pno_mutex);
 exit_no_unlock:
-       if (waitqueue_active(&_pno_state->get_batch_done.wait))
+       if (swait_active(&_pno_state->get_batch_done.wait))
                complete(&_pno_state->get_batch_done);
        return err;
 }
@@ -3948,7 +3948,7 @@ dhd_pno_event_handler(dhd_pub_t *dhd, wl_event_msg_t *event, void *event_data)
        {
                struct dhd_pno_batch_params *params_batch;
                params_batch = &_pno_state->pno_params_arr[INDEX_OF_BATCH_PARAMS].params_batch;
-               if (!waitqueue_active(&_pno_state->get_batch_done.wait)) {
+               if (!swait_active(&_pno_state->get_batch_done.wait)) {
                        DHD_PNO(("%s : WLC_E_PFN_BEST_BATCHING\n", __FUNCTION__));
                        params_batch->get_batch.buf = NULL;
                        params_batch->get_batch.bufsize = 0;
index 4e91c74..0f7d2bf 100644 (file)
@@ -697,7 +697,7 @@ static void ezusb_req_ctx_wait(struct ezusb_priv *upriv,
                        while (!ctx->done.done && msecs--)
                                udelay(1000);
                } else {
-                       wait_event_interruptible(ctx->done.wait,
+                       swait_event_interruptible(ctx->done.wait,
                                                 ctx->done.done);
                }
                break;
index 5aa2214..42d9fb3 100644 (file)
@@ -61,7 +61,7 @@ struct msm_pinctrl {
        struct notifier_block restart_nb;
        int irq;
 
-       spinlock_t lock;
+       raw_spinlock_t lock;
 
        DECLARE_BITMAP(dual_edge_irqs, MAX_NR_GPIO);
        DECLARE_BITMAP(enabled_irqs, MAX_NR_GPIO);
@@ -153,14 +153,14 @@ static int msm_pinmux_set_mux(struct pinctrl_dev *pctldev,
        if (WARN_ON(i == g->nfuncs))
                return -EINVAL;
 
-       spin_lock_irqsave(&pctrl->lock, flags);
+       raw_spin_lock_irqsave(&pctrl->lock, flags);
 
        val = readl(pctrl->regs + g->ctl_reg);
        val &= ~mask;
        val |= i << g->mux_bit;
        writel(val, pctrl->regs + g->ctl_reg);
 
-       spin_unlock_irqrestore(&pctrl->lock, flags);
+       raw_spin_unlock_irqrestore(&pctrl->lock, flags);
 
        return 0;
 }
@@ -323,14 +323,14 @@ static int msm_config_group_set(struct pinctrl_dev *pctldev,
                        break;
                case PIN_CONFIG_OUTPUT:
                        /* set output value */
-                       spin_lock_irqsave(&pctrl->lock, flags);
+                       raw_spin_lock_irqsave(&pctrl->lock, flags);
                        val = readl(pctrl->regs + g->io_reg);
                        if (arg)
                                val |= BIT(g->out_bit);
                        else
                                val &= ~BIT(g->out_bit);
                        writel(val, pctrl->regs + g->io_reg);
-                       spin_unlock_irqrestore(&pctrl->lock, flags);
+                       raw_spin_unlock_irqrestore(&pctrl->lock, flags);
 
                        /* enable output */
                        arg = 1;
@@ -351,12 +351,12 @@ static int msm_config_group_set(struct pinctrl_dev *pctldev,
                        return -EINVAL;
                }
 
-               spin_lock_irqsave(&pctrl->lock, flags);
+               raw_spin_lock_irqsave(&pctrl->lock, flags);
                val = readl(pctrl->regs + g->ctl_reg);
                val &= ~(mask << bit);
                val |= arg << bit;
                writel(val, pctrl->regs + g->ctl_reg);
-               spin_unlock_irqrestore(&pctrl->lock, flags);
+               raw_spin_unlock_irqrestore(&pctrl->lock, flags);
        }
 
        return 0;
@@ -384,13 +384,13 @@ static int msm_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 
        g = &pctrl->soc->groups[offset];
 
-       spin_lock_irqsave(&pctrl->lock, flags);
+       raw_spin_lock_irqsave(&pctrl->lock, flags);
 
        val = readl(pctrl->regs + g->ctl_reg);
        val &= ~BIT(g->oe_bit);
        writel(val, pctrl->regs + g->ctl_reg);
 
-       spin_unlock_irqrestore(&pctrl->lock, flags);
+       raw_spin_unlock_irqrestore(&pctrl->lock, flags);
 
        return 0;
 }
@@ -404,7 +404,7 @@ static int msm_gpio_direction_output(struct gpio_chip *chip, unsigned offset, in
 
        g = &pctrl->soc->groups[offset];
 
-       spin_lock_irqsave(&pctrl->lock, flags);
+       raw_spin_lock_irqsave(&pctrl->lock, flags);
 
        val = readl(pctrl->regs + g->io_reg);
        if (value)
@@ -417,7 +417,7 @@ static int msm_gpio_direction_output(struct gpio_chip *chip, unsigned offset, in
        val |= BIT(g->oe_bit);
        writel(val, pctrl->regs + g->ctl_reg);
 
-       spin_unlock_irqrestore(&pctrl->lock, flags);
+       raw_spin_unlock_irqrestore(&pctrl->lock, flags);
 
        return 0;
 }
@@ -443,7 +443,7 @@ static void msm_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 
        g = &pctrl->soc->groups[offset];
 
-       spin_lock_irqsave(&pctrl->lock, flags);
+       raw_spin_lock_irqsave(&pctrl->lock, flags);
 
        val = readl(pctrl->regs + g->io_reg);
        if (value)
@@ -452,7 +452,7 @@ static void msm_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
                val &= ~BIT(g->out_bit);
        writel(val, pctrl->regs + g->io_reg);
 
-       spin_unlock_irqrestore(&pctrl->lock, flags);
+       raw_spin_unlock_irqrestore(&pctrl->lock, flags);
 }
 
 #ifdef CONFIG_DEBUG_FS
@@ -571,7 +571,7 @@ static void msm_gpio_irq_mask(struct irq_data *d)
 
        g = &pctrl->soc->groups[d->hwirq];
 
-       spin_lock_irqsave(&pctrl->lock, flags);
+       raw_spin_lock_irqsave(&pctrl->lock, flags);
 
        val = readl(pctrl->regs + g->intr_cfg_reg);
        val &= ~BIT(g->intr_enable_bit);
@@ -579,7 +579,7 @@ static void msm_gpio_irq_mask(struct irq_data *d)
 
        clear_bit(d->hwirq, pctrl->enabled_irqs);
 
-       spin_unlock_irqrestore(&pctrl->lock, flags);
+       raw_spin_unlock_irqrestore(&pctrl->lock, flags);
 }
 
 static void msm_gpio_irq_unmask(struct irq_data *d)
@@ -592,7 +592,7 @@ static void msm_gpio_irq_unmask(struct irq_data *d)
 
        g = &pctrl->soc->groups[d->hwirq];
 
-       spin_lock_irqsave(&pctrl->lock, flags);
+       raw_spin_lock_irqsave(&pctrl->lock, flags);
 
        val = readl(pctrl->regs + g->intr_cfg_reg);
        val |= BIT(g->intr_enable_bit);
@@ -600,7 +600,7 @@ static void msm_gpio_irq_unmask(struct irq_data *d)
 
        set_bit(d->hwirq, pctrl->enabled_irqs);
 
-       spin_unlock_irqrestore(&pctrl->lock, flags);
+       raw_spin_unlock_irqrestore(&pctrl->lock, flags);
 }
 
 static void msm_gpio_irq_ack(struct irq_data *d)
@@ -613,7 +613,7 @@ static void msm_gpio_irq_ack(struct irq_data *d)
 
        g = &pctrl->soc->groups[d->hwirq];
 
-       spin_lock_irqsave(&pctrl->lock, flags);
+       raw_spin_lock_irqsave(&pctrl->lock, flags);
 
        val = readl(pctrl->regs + g->intr_status_reg);
        if (g->intr_ack_high)
@@ -625,7 +625,7 @@ static void msm_gpio_irq_ack(struct irq_data *d)
        if (test_bit(d->hwirq, pctrl->dual_edge_irqs))
                msm_gpio_update_dual_edge_pos(pctrl, g, d);
 
-       spin_unlock_irqrestore(&pctrl->lock, flags);
+       raw_spin_unlock_irqrestore(&pctrl->lock, flags);
 }
 
 static int msm_gpio_irq_set_type(struct irq_data *d, unsigned int type)
@@ -638,7 +638,7 @@ static int msm_gpio_irq_set_type(struct irq_data *d, unsigned int type)
 
        g = &pctrl->soc->groups[d->hwirq];
 
-       spin_lock_irqsave(&pctrl->lock, flags);
+       raw_spin_lock_irqsave(&pctrl->lock, flags);
 
        /*
         * For hw without possibility of detecting both edges
@@ -712,7 +712,7 @@ static int msm_gpio_irq_set_type(struct irq_data *d, unsigned int type)
        if (test_bit(d->hwirq, pctrl->dual_edge_irqs))
                msm_gpio_update_dual_edge_pos(pctrl, g, d);
 
-       spin_unlock_irqrestore(&pctrl->lock, flags);
+       raw_spin_unlock_irqrestore(&pctrl->lock, flags);
 
        if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
                irq_set_handler_locked(d, handle_level_irq);
@@ -728,11 +728,11 @@ static int msm_gpio_irq_set_wake(struct irq_data *d, unsigned int on)
        struct msm_pinctrl *pctrl = gpiochip_get_data(gc);
        unsigned long flags;
 
-       spin_lock_irqsave(&pctrl->lock, flags);
+       raw_spin_lock_irqsave(&pctrl->lock, flags);
 
        irq_set_irq_wake(pctrl->irq, on);
 
-       spin_unlock_irqrestore(&pctrl->lock, flags);
+       raw_spin_unlock_irqrestore(&pctrl->lock, flags);
 
        return 0;
 }
@@ -891,7 +891,7 @@ int msm_pinctrl_probe(struct platform_device *pdev,
        pctrl->soc = soc_data;
        pctrl->chip = msm_gpio_template;
 
-       spin_lock_init(&pctrl->lock);
+       raw_spin_lock_init(&pctrl->lock);
 
        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        pctrl->regs = devm_ioremap_resource(&pdev->dev, res);
index 9bd41a3..8e2d436 100644 (file)
@@ -1455,11 +1455,11 @@ err2:
 static int fcoe_alloc_paged_crc_eof(struct sk_buff *skb, int tlen)
 {
        struct fcoe_percpu_s *fps;
-       int rc;
+       int rc, cpu = get_cpu_light();
 
-       fps = &get_cpu_var(fcoe_percpu);
+       fps = &per_cpu(fcoe_percpu, cpu);
        rc = fcoe_get_paged_crc_eof(skb, tlen, fps);
-       put_cpu_var(fcoe_percpu);
+       put_cpu_light();
 
        return rc;
 }
@@ -1646,11 +1646,11 @@ static inline int fcoe_filter_frames(struct fc_lport *lport,
                return 0;
        }
 
-       stats = per_cpu_ptr(lport->stats, get_cpu());
+       stats = per_cpu_ptr(lport->stats, get_cpu_light());
        stats->InvalidCRCCount++;
        if (stats->InvalidCRCCount < 5)
                printk(KERN_WARNING "fcoe: dropping frame with CRC error\n");
-       put_cpu();
+       put_cpu_light();
        return -EINVAL;
 }
 
@@ -1693,7 +1693,7 @@ static void fcoe_recv_frame(struct sk_buff *skb)
         */
        hp = (struct fcoe_hdr *) skb_network_header(skb);
 
-       stats = per_cpu_ptr(lport->stats, get_cpu());
+       stats = per_cpu_ptr(lport->stats, get_cpu_light());
        if (unlikely(FC_FCOE_DECAPS_VER(hp) != FC_FCOE_VER)) {
                if (stats->ErrorFrames < 5)
                        printk(KERN_WARNING "fcoe: FCoE version "
@@ -1725,13 +1725,13 @@ static void fcoe_recv_frame(struct sk_buff *skb)
                goto drop;
 
        if (!fcoe_filter_frames(lport, fp)) {
-               put_cpu();
+               put_cpu_light();
                fc_exch_recv(lport, fp);
                return;
        }
 drop:
        stats->ErrorFrames++;
-       put_cpu();
+       put_cpu_light();
        kfree_skb(skb);
 }
 
index f5f3a81..59ab3b4 100644 (file)
@@ -834,7 +834,7 @@ static unsigned long fcoe_ctlr_age_fcfs(struct fcoe_ctlr *fip)
 
        INIT_LIST_HEAD(&del_list);
 
-       stats = per_cpu_ptr(fip->lp->stats, get_cpu());
+       stats = per_cpu_ptr(fip->lp->stats, get_cpu_light());
 
        list_for_each_entry_safe(fcf, next, &fip->fcfs, list) {
                deadline = fcf->time + fcf->fka_period + fcf->fka_period / 2;
@@ -870,7 +870,7 @@ static unsigned long fcoe_ctlr_age_fcfs(struct fcoe_ctlr *fip)
                                sel_time = fcf->time;
                }
        }
-       put_cpu();
+       put_cpu_light();
 
        list_for_each_entry_safe(fcf, next, &del_list, list) {
                /* Removes fcf from current list */
index d0a86ef..6b692e5 100644 (file)
@@ -814,10 +814,10 @@ static struct fc_exch *fc_exch_em_alloc(struct fc_lport *lport,
        }
        memset(ep, 0, sizeof(*ep));
 
-       cpu = get_cpu();
+       cpu = get_cpu_light();
        pool = per_cpu_ptr(mp->pool, cpu);
        spin_lock_bh(&pool->lock);
-       put_cpu();
+       put_cpu_light();
 
        /* peek cache of free slot */
        if (pool->left != FC_XID_UNKNOWN) {
index b820c3a..2b96e30 100644 (file)
@@ -190,7 +190,7 @@ static unsigned int sas_ata_qc_issue(struct ata_queued_cmd *qc)
        /* TODO: audit callers to ensure they are ready for qc_issue to
         * unconditionally re-enable interrupts
         */
-       local_irq_save(flags);
+       local_irq_save_nort(flags);
        spin_unlock(ap->lock);
 
        /* If the device fell off, no sense in issuing commands */
@@ -255,7 +255,7 @@ static unsigned int sas_ata_qc_issue(struct ata_queued_cmd *qc)
 
  out:
        spin_lock(ap->lock);
-       local_irq_restore(flags);
+       local_irq_restore_nort(flags);
        return ret;
 }
 
index edc48f3..ee5c6f9 100644 (file)
@@ -59,12 +59,12 @@ qla2x00_poll(struct rsp_que *rsp)
 {
        unsigned long flags;
        struct qla_hw_data *ha = rsp->hw;
-       local_irq_save(flags);
+       local_irq_save_nort(flags);
        if (IS_P3P_TYPE(ha))
                qla82xx_poll(0, rsp);
        else
                ha->isp_ops->intr_handler(0, rsp);
-       local_irq_restore(flags);
+       local_irq_restore_nort(flags);
 }
 
 static inline uint8_t *
index 17b1525..6249c4b 100644 (file)
@@ -3127,7 +3127,11 @@ qla24xx_enable_msix(struct qla_hw_data *ha, struct rsp_que *rsp)
                * kref_put().
                */
                kref_get(&qentry->irq_notify.kref);
+#ifdef CONFIG_PREEMPT_RT_BASE
+               swork_queue(&qentry->irq_notify.swork);
+#else
                schedule_work(&qentry->irq_notify.work);
+#endif
        }
 
        /*
index 95f4c1b..0be9347 100644 (file)
@@ -29,6 +29,7 @@
 #include <linux/pm.h>
 #include <linux/thermal.h>
 #include <linux/debugfs.h>
+#include <linux/swork.h>
 #include <asm/cpu_device_id.h>
 #include <asm/mce.h>
 
@@ -353,7 +354,7 @@ static void pkg_temp_thermal_threshold_work_fn(struct work_struct *work)
        }
 }
 
-static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val)
+static void platform_thermal_notify_work(struct swork_event *event)
 {
        unsigned long flags;
        int cpu = smp_processor_id();
@@ -370,7 +371,7 @@ static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val)
                        pkg_work_scheduled[phy_id]) {
                disable_pkg_thres_interrupt();
                spin_unlock_irqrestore(&pkg_work_lock, flags);
-               return -EINVAL;
+               return;
        }
        pkg_work_scheduled[phy_id] = 1;
        spin_unlock_irqrestore(&pkg_work_lock, flags);
@@ -379,9 +380,48 @@ static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val)
        schedule_delayed_work_on(cpu,
                                &per_cpu(pkg_temp_thermal_threshold_work, cpu),
                                msecs_to_jiffies(notify_delay_ms));
+}
+
+#ifdef CONFIG_PREEMPT_RT_FULL
+static struct swork_event notify_work;
+
+static int thermal_notify_work_init(void)
+{
+       int err;
+
+       err = swork_get();
+       if (err)
+               return err;
+
+       INIT_SWORK(&notify_work, platform_thermal_notify_work);
        return 0;
 }
 
+static void thermal_notify_work_cleanup(void)
+{
+       swork_put();
+}
+
+static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val)
+{
+       swork_queue(&notify_work);
+       return 0;
+}
+
+#else  /* !CONFIG_PREEMPT_RT_FULL */
+
+static int thermal_notify_work_init(void) { return 0; }
+
+static void thermal_notify_work_cleanup(void) {  }
+
+static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val)
+{
+       platform_thermal_notify_work(NULL);
+
+       return 0;
+}
+#endif /* CONFIG_PREEMPT_RT_FULL */
+
 static int find_siblings_cpu(int cpu)
 {
        int i;
@@ -585,6 +625,9 @@ static int __init pkg_temp_thermal_init(void)
        if (!x86_match_cpu(pkg_temp_thermal_ids))
                return -ENODEV;
 
+       if (!thermal_notify_work_init())
+               return -ENODEV;
+
        spin_lock_init(&pkg_work_lock);
        platform_thermal_package_notify =
                        pkg_temp_thermal_platform_thermal_notify;
@@ -609,7 +652,7 @@ err_ret:
        kfree(pkg_work_scheduled);
        platform_thermal_package_notify = NULL;
        platform_thermal_package_rate_control = NULL;
-
+       thermal_notify_work_cleanup();
        return -ENODEV;
 }
 
@@ -634,6 +677,7 @@ static void __exit pkg_temp_thermal_exit(void)
        mutex_unlock(&phy_dev_list_mutex);
        platform_thermal_package_notify = NULL;
        platform_thermal_package_rate_control = NULL;
+       thermal_notify_work_cleanup();
        for_each_online_cpu(i)
                cancel_delayed_work_sync(
                        &per_cpu(pkg_temp_thermal_threshold_work, i));
index 8dbfd4f..64f54b7 100644 (file)
@@ -58,7 +58,16 @@ static struct uart_driver serial8250_reg;
 
 static unsigned int skip_txen_test; /* force skip of txen test at init time */
 
-#define PASS_LIMIT     512
+/*
+ * On -rt we can have a more delays, and legitimately
+ * so - so don't drop work spuriously and spam the
+ * syslog:
+ */
+#ifdef CONFIG_PREEMPT_RT_FULL
+# define PASS_LIMIT    1000000
+#else
+# define PASS_LIMIT    512
+#endif
 
 #include <asm/serial.h>
 /*
index 827a641..fea0274 100644 (file)
@@ -35,6 +35,7 @@
 #include <linux/nmi.h>
 #include <linux/mutex.h>
 #include <linux/slab.h>
+#include <linux/kdb.h>
 #include <linux/uaccess.h>
 #include <linux/pm_runtime.h>
 #include <linux/timer.h>
@@ -3164,9 +3165,9 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
 
        serial8250_rpm_get(up);
 
-       if (port->sysrq)
+       if (port->sysrq || oops_in_progress)
                locked = 0;
-       else if (oops_in_progress)
+       else if (in_kdb_printk())
                locked = spin_trylock_irqsave(&port->lock, flags);
        else
                spin_lock_irqsave(&port->lock, flags);
index 6e27dee..d402f49 100644 (file)
@@ -2213,13 +2213,19 @@ pl011_console_write(struct console *co, const char *s, unsigned int count)
 
        clk_enable(uap->clk);
 
-       local_irq_save(flags);
+       /*
+        * local_irq_save(flags);
+        *
+        * This local_irq_save() is nonsense. If we come in via sysrq
+        * handling then interrupts are already disabled. Aside of
+        * that the port.sysrq check is racy on SMP regardless.
+       */
        if (uap->port.sysrq)
                locked = 0;
        else if (oops_in_progress)
-               locked = spin_trylock(&uap->port.lock);
+               locked = spin_trylock_irqsave(&uap->port.lock, flags);
        else
-               spin_lock(&uap->port.lock);
+               spin_lock_irqsave(&uap->port.lock, flags);
 
        /*
         *      First save the CR then disable the interrupts
@@ -2243,8 +2249,7 @@ pl011_console_write(struct console *co, const char *s, unsigned int count)
                pl011_write(old_cr, uap, REG_CR);
 
        if (locked)
-               spin_unlock(&uap->port.lock);
-       local_irq_restore(flags);
+               spin_unlock_irqrestore(&uap->port.lock, flags);
 
        clk_disable(uap->clk);
 }
index 472ba3c..e654cb4 100644 (file)
@@ -1257,13 +1257,10 @@ serial_omap_console_write(struct console *co, const char *s,
 
        pm_runtime_get_sync(up->dev);
 
-       local_irq_save(flags);
-       if (up->port.sysrq)
-               locked = 0;
-       else if (oops_in_progress)
-               locked = spin_trylock(&up->port.lock);
+       if (up->port.sysrq || oops_in_progress)
+               locked = spin_trylock_irqsave(&up->port.lock, flags);
        else
-               spin_lock(&up->port.lock);
+               spin_lock_irqsave(&up->port.lock, flags);
 
        /*
         * First save the IER then disable the interrupts
@@ -1292,8 +1289,7 @@ serial_omap_console_write(struct console *co, const char *s,
        pm_runtime_mark_last_busy(up->dev);
        pm_runtime_put_autosuspend(up->dev);
        if (locked)
-               spin_unlock(&up->port.lock);
-       local_irq_restore(flags);
+               spin_unlock_irqrestore(&up->port.lock, flags);
 }
 
 static int __init
index aad2018..ee75093 100644 (file)
@@ -1778,11 +1778,11 @@ static void __usb_hcd_giveback_urb(struct urb *urb)
         */
 
 #ifndef CONFIG_AMLOGIC_USB
-       local_irq_save(flags);
+       local_irq_save_nort(flags);
 #endif
        urb->complete(urb);
 #ifndef CONFIG_AMLOGIC_USB
-       local_irq_restore(flags);
+       local_irq_restore_nort(flags);
 #endif
 
        usb_anchor_resume_wakeups(anchor);
index df74bfa..6ed905a 100644 (file)
@@ -1819,7 +1819,7 @@ static void ffs_data_put(struct ffs_data *ffs)
                pr_info("%s(): freeing\n", __func__);
                ffs_data_clear(ffs);
                BUG_ON(waitqueue_active(&ffs->ev.waitq) ||
-                      waitqueue_active(&ffs->ep0req_completion.wait));
+                      swait_active(&ffs->ep0req_completion.wait));
                kfree(ffs->dev_name);
                kfree(ffs);
        }
index cb02e9e..a782a04 100644 (file)
@@ -347,7 +347,7 @@ ep_io (struct ep_data *epdata, void *buf, unsigned len)
        spin_unlock_irq (&epdata->dev->lock);
 
        if (likely (value == 0)) {
-               value = wait_event_interruptible (done.wait, done.done);
+               value = swait_event_interruptible (done.wait, done.done);
                if (value != 0) {
                        spin_lock_irq (&epdata->dev->lock);
                        if (likely (epdata->ep != NULL)) {
@@ -356,7 +356,7 @@ ep_io (struct ep_data *epdata, void *buf, unsigned len)
                                usb_ep_dequeue (epdata->ep, epdata->req);
                                spin_unlock_irq (&epdata->dev->lock);
 
-                               wait_event (done.wait, done.done);
+                               swait_event (done.wait, done.done);
                                if (epdata->status == -ECONNRESET)
                                        epdata->status = -EINTR;
                        } else {
index c3fc802..b79c93d 100644 (file)
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -41,6 +41,7 @@
 #include <linux/percpu-refcount.h>
 #include <linux/mount.h>
 #include <linux/nospec.h>
+#include <linux/swork.h>
 
 #include <asm/kmap_types.h>
 #include <asm/uaccess.h>
@@ -118,6 +119,7 @@ struct kioctx {
 
        struct rcu_head         free_rcu;
        struct work_struct      free_work;      /* see free_ioctx() */
+       struct swork_event      free_swork;     /* see free_ioctx_users() */
 
        /*
         * signals when all in-flight requests are done
@@ -260,6 +262,7 @@ static int __init aio_setup(void)
                .mount          = aio_mount,
                .kill_sb        = kill_anon_super,
        };
+       BUG_ON(swork_get());
        aio_mnt = kern_mount(&aio_fs);
        if (IS_ERR(aio_mnt))
                panic("Failed to create aio fs mount.");
@@ -627,9 +630,9 @@ static void free_ioctx_reqs(struct percpu_ref *ref)
  * and ctx->users has dropped to 0, so we know no more kiocbs can be submitted -
  * now it's safe to cancel any that need to be.
  */
-static void free_ioctx_users(struct percpu_ref *ref)
+static void free_ioctx_users_work(struct swork_event *sev)
 {
-       struct kioctx *ctx = container_of(ref, struct kioctx, users);
+       struct kioctx *ctx = container_of(sev, struct kioctx, free_swork);
        struct aio_kiocb *req;
 
        spin_lock_irq(&ctx->ctx_lock);
@@ -647,6 +650,14 @@ static void free_ioctx_users(struct percpu_ref *ref)
        percpu_ref_put(&ctx->reqs);
 }
 
+static void free_ioctx_users(struct percpu_ref *ref)
+{
+       struct kioctx *ctx = container_of(ref, struct kioctx, users);
+
+       INIT_SWORK(&ctx->free_swork, free_ioctx_users_work);
+       swork_queue(&ctx->free_swork);
+}
+
 static int ioctx_add_table(struct kioctx *ctx, struct mm_struct *mm)
 {
        unsigned i, new_nr;
index 42f8633..e4deae2 100644 (file)
@@ -32,6 +32,7 @@
 #include <linux/sched.h>
 #include <linux/mount.h>
 #include <linux/namei.h>
+#include <linux/delay.h>
 #include <asm/current.h>
 #include <linux/uaccess.h>
 
index 02f0d37..1454264 100644 (file)
@@ -148,7 +148,7 @@ again:
                        parent = p->d_parent;
                        if (!spin_trylock(&parent->d_lock)) {
                                spin_unlock(&p->d_lock);
-                               cpu_relax();
+                               cpu_chill();
                                goto relock;
                        }
                        spin_unlock(&p->d_lock);
index 52f1a60..7534bbe 100644 (file)
@@ -302,8 +302,7 @@ static void end_buffer_async_read(struct buffer_head *bh, int uptodate)
         * decide that the page is now completely done.
         */
        first = page_buffers(page);
-       local_irq_save(flags);
-       bit_spin_lock(BH_Uptodate_Lock, &first->b_state);
+       flags = bh_uptodate_lock_irqsave(first);
        clear_buffer_async_read(bh);
        unlock_buffer(bh);
        tmp = bh;
@@ -316,8 +315,7 @@ static void end_buffer_async_read(struct buffer_head *bh, int uptodate)
                }
                tmp = tmp->b_this_page;
        } while (tmp != bh);
-       bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
-       local_irq_restore(flags);
+       bh_uptodate_unlock_irqrestore(first, flags);
 
        /*
         * If none of the buffers had errors and they are all
@@ -329,9 +327,7 @@ static void end_buffer_async_read(struct buffer_head *bh, int uptodate)
        return;
 
 still_busy:
-       bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
-       local_irq_restore(flags);
-       return;
+       bh_uptodate_unlock_irqrestore(first, flags);
 }
 
 /*
@@ -359,8 +355,7 @@ void end_buffer_async_write(struct buffer_head *bh, int uptodate)
        }
 
        first = page_buffers(page);
-       local_irq_save(flags);
-       bit_spin_lock(BH_Uptodate_Lock, &first->b_state);
+       flags = bh_uptodate_lock_irqsave(first);
 
        clear_buffer_async_write(bh);
        unlock_buffer(bh);
@@ -372,15 +367,12 @@ void end_buffer_async_write(struct buffer_head *bh, int uptodate)
                }
                tmp = tmp->b_this_page;
        }
-       bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
-       local_irq_restore(flags);
+       bh_uptodate_unlock_irqrestore(first, flags);
        end_page_writeback(page);
        return;
 
 still_busy:
-       bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
-       local_irq_restore(flags);
-       return;
+       bh_uptodate_unlock_irqrestore(first, flags);
 }
 EXPORT_SYMBOL(end_buffer_async_write);
 
@@ -3400,6 +3392,7 @@ struct buffer_head *alloc_buffer_head(gfp_t gfp_flags)
        struct buffer_head *ret = kmem_cache_zalloc(bh_cachep, gfp_flags);
        if (ret) {
                INIT_LIST_HEAD(&ret->b_assoc_buffers);
+               buffer_head_init_locks(ret);
                preempt_disable();
                __this_cpu_inc(bh_accounting.nr);
                recalc_bh_state();
index 6818387..56b5d9a 100644 (file)
@@ -80,7 +80,7 @@ cifs_prime_dcache(struct dentry *parent, struct qstr *name,
        struct inode *inode;
        struct super_block *sb = parent->d_sb;
        struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
-       DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+       DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
 
        cifs_dbg(FYI, "%s: for %s\n", __func__, name->name);
 
index 426fe9b..37df283 100644 (file)
@@ -19,6 +19,7 @@
 #include <linux/mm.h>
 #include <linux/fs.h>
 #include <linux/fsnotify.h>
+#include <linux/delay.h>
 #include <linux/slab.h>
 #include <linux/init.h>
 #include <linux/hash.h>
@@ -787,6 +788,8 @@ static inline bool fast_dput(struct dentry *dentry)
  */
 void dput(struct dentry *dentry)
 {
+       struct dentry *parent;
+
        if (unlikely(!dentry))
                return;
 
@@ -825,9 +828,18 @@ repeat:
        return;
 
 kill_it:
-       dentry = dentry_kill(dentry);
-       if (dentry) {
-               cond_resched();
+       parent = dentry_kill(dentry);
+       if (parent) {
+               int r;
+
+               if (parent == dentry) {
+                       /* the task with the highest priority won't schedule */
+                       r = cond_resched();
+                       if (!r)
+                               cpu_chill();
+               } else {
+                       dentry = parent;
+               }
                goto repeat;
        }
 }
@@ -2380,7 +2392,7 @@ again:
        if (dentry->d_lockref.count == 1) {
                if (!spin_trylock(&inode->i_lock)) {
                        spin_unlock(&dentry->d_lock);
-                       cpu_relax();
+                       cpu_chill();
                        goto again;
                }
                dentry->d_flags &= ~DCACHE_CANT_MOUNT;
@@ -2425,9 +2437,10 @@ EXPORT_SYMBOL(d_rehash);
 static inline unsigned start_dir_add(struct inode *dir)
 {
 
+       preempt_disable_rt();
        for (;;) {
-               unsigned n = dir->i_dir_seq;
-               if (!(n & 1) && cmpxchg(&dir->i_dir_seq, n, n + 1) == n)
+               unsigned n = dir->__i_dir_seq;
+               if (!(n & 1) && cmpxchg(&dir->__i_dir_seq, n, n + 1) == n)
                        return n;
                cpu_relax();
        }
@@ -2435,26 +2448,30 @@ static inline unsigned start_dir_add(struct inode *dir)
 
 static inline void end_dir_add(struct inode *dir, unsigned n)
 {
-       smp_store_release(&dir->i_dir_seq, n + 2);
+       smp_store_release(&dir->__i_dir_seq, n + 2);
+       preempt_enable_rt();
 }
 
 static void d_wait_lookup(struct dentry *dentry)
 {
-       if (d_in_lookup(dentry)) {
-               DECLARE_WAITQUEUE(wait, current);
-               add_wait_queue(dentry->d_wait, &wait);
-               do {
-                       set_current_state(TASK_UNINTERRUPTIBLE);
-                       spin_unlock(&dentry->d_lock);
-                       schedule();
-                       spin_lock(&dentry->d_lock);
-               } while (d_in_lookup(dentry));
-       }
+       struct swait_queue __wait;
+
+       if (!d_in_lookup(dentry))
+               return;
+
+       INIT_LIST_HEAD(&__wait.task_list);
+       do {
+               prepare_to_swait(dentry->d_wait, &__wait, TASK_UNINTERRUPTIBLE);
+               spin_unlock(&dentry->d_lock);
+               schedule();
+               spin_lock(&dentry->d_lock);
+       } while (d_in_lookup(dentry));
+       finish_swait(dentry->d_wait, &__wait);
 }
 
 struct dentry *d_alloc_parallel(struct dentry *parent,
                                const struct qstr *name,
-                               wait_queue_head_t *wq)
+                               struct swait_queue_head *wq)
 {
        unsigned int hash = name->hash;
        struct hlist_bl_head *b = in_lookup_hash(parent, hash);
@@ -2468,7 +2485,7 @@ struct dentry *d_alloc_parallel(struct dentry *parent,
 
 retry:
        rcu_read_lock();
-       seq = smp_load_acquire(&parent->d_inode->i_dir_seq);
+       seq = smp_load_acquire(&parent->d_inode->__i_dir_seq);
        r_seq = read_seqbegin(&rename_lock);
        dentry = __d_lookup_rcu(parent, name, &d_seq);
        if (unlikely(dentry)) {
@@ -2496,7 +2513,7 @@ retry:
        }
 
        hlist_bl_lock(b);
-       if (unlikely(READ_ONCE(parent->d_inode->i_dir_seq) != seq)) {
+       if (unlikely(READ_ONCE(parent->d_inode->__i_dir_seq) != seq)) {
                hlist_bl_unlock(b);
                rcu_read_unlock();
                goto retry;
@@ -2569,7 +2586,7 @@ void __d_lookup_done(struct dentry *dentry)
        hlist_bl_lock(b);
        dentry->d_flags &= ~DCACHE_PAR_LOOKUP;
        __hlist_bl_del(&dentry->d_u.d_in_lookup_hash);
-       wake_up_all(dentry->d_wait);
+       swake_up_all(dentry->d_wait);
        dentry->d_wait = NULL;
        hlist_bl_unlock(b);
        INIT_HLIST_NODE(&dentry->d_u.d_alias);
@@ -3669,6 +3686,11 @@ EXPORT_SYMBOL(d_genocide);
 
 void __init vfs_caches_init_early(void)
 {
+       int i;
+
+       for (i = 0; i < ARRAY_SIZE(in_lookup_hashtable); i++)
+               INIT_HLIST_BL_HEAD(&in_lookup_hashtable[i]);
+
        dcache_init_early();
        inode_init_early();
 }
index bb3f4be..f44567d 100644 (file)
@@ -509,12 +509,12 @@ static int ep_poll_wakeup_proc(void *priv, void *cookie, int call_nests)
  */
 static void ep_poll_safewake(wait_queue_head_t *wq)
 {
-       int this_cpu = get_cpu();
+       int this_cpu = get_cpu_light();
 
        ep_call_nested(&poll_safewake_ncalls, EP_MAX_NESTS,
                       ep_poll_wakeup_proc, NULL, wq, (void *) (long) this_cpu);
 
-       put_cpu();
+       put_cpu_light();
 }
 
 static void ep_remove_wait_queue(struct eppoll_entry *pwq)
index 84e792c..2617782 100644 (file)
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1038,12 +1038,14 @@ static int exec_mmap(struct mm_struct *mm)
                }
        }
        task_lock(tsk);
+       preempt_disable_rt();
        active_mm = tsk->active_mm;
        tsk->mm = mm;
        tsk->active_mm = mm;
        activate_mm(active_mm, mm);
        tsk->mm->vmacache_seqnum = 0;
        vmacache_flush(tsk);
+       preempt_enable_rt();
        task_unlock(tsk);
        if (old_mm) {
                up_read(&old_mm->mmap_sem);
index d68032b..e395a96 100644 (file)
@@ -94,8 +94,7 @@ static void ext4_finish_bio(struct bio *bio)
                 * We check all buffers in the page under BH_Uptodate_Lock
                 * to avoid races with other end io clearing async_write flags
                 */
-               local_irq_save(flags);
-               bit_spin_lock(BH_Uptodate_Lock, &head->b_state);
+               flags = bh_uptodate_lock_irqsave(head);
                do {
                        if (bh_offset(bh) < bio_start ||
                            bh_offset(bh) + bh->b_size > bio_end) {
@@ -107,8 +106,7 @@ static void ext4_finish_bio(struct bio *bio)
                        if (bio->bi_error)
                                buffer_io_error(bh);
                } while ((bh = bh->b_this_page) != head);
-               bit_spin_unlock(BH_Uptodate_Lock, &head->b_state);
-               local_irq_restore(flags);
+               bh_uptodate_unlock_irqrestore(head, flags);
                if (!under_io) {
 #ifdef CONFIG_EXT4_FS_ENCRYPTION
                        if (data_page)
index 531ecc7..c379f1e 100644 (file)
@@ -1248,7 +1248,7 @@ static int fuse_direntplus_link(struct file *file,
        struct inode *dir = d_inode(parent);
        struct fuse_conn *fc;
        struct inode *inode;
-       DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+       DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
 
        if (!o->nodeid) {
                /*
index 34ff139..1c2a125 100644 (file)
@@ -154,7 +154,7 @@ int inode_init_always(struct super_block *sb, struct inode *inode)
        inode->i_bdev = NULL;
        inode->i_cdev = NULL;
        inode->i_link = NULL;
-       inode->i_dir_seq = 0;
+       inode->__i_dir_seq = 0;
        inode->i_rdev = 0;
        inode->dirtied_when = 0;
 
index 8252647..36d8752 100644 (file)
@@ -935,7 +935,7 @@ static int flock_lock_inode(struct inode *inode, struct file_lock *request)
                        return -ENOMEM;
        }
 
-       percpu_down_read_preempt_disable(&file_rwsem);
+       percpu_down_read(&file_rwsem);
        spin_lock(&ctx->flc_lock);
        if (request->fl_flags & FL_ACCESS)
                goto find_conflict;
@@ -976,7 +976,7 @@ find_conflict:
 
 out:
        spin_unlock(&ctx->flc_lock);
-       percpu_up_read_preempt_enable(&file_rwsem);
+       percpu_up_read(&file_rwsem);
        if (new_fl)
                locks_free_lock(new_fl);
        locks_dispose_list(&dispose);
@@ -1013,7 +1013,7 @@ static int posix_lock_inode(struct inode *inode, struct file_lock *request,
                new_fl2 = locks_alloc_lock();
        }
 
-       percpu_down_read_preempt_disable(&file_rwsem);
+       percpu_down_read(&file_rwsem);
        spin_lock(&ctx->flc_lock);
        /*
         * New lock request. Walk all POSIX locks and look for conflicts. If
@@ -1185,7 +1185,7 @@ static int posix_lock_inode(struct inode *inode, struct file_lock *request,
        }
  out:
        spin_unlock(&ctx->flc_lock);
-       percpu_up_read_preempt_enable(&file_rwsem);
+       percpu_up_read(&file_rwsem);
        /*
         * Free any unused locks.
         */
@@ -1460,7 +1460,7 @@ int __break_lease(struct inode *inode, unsigned int mode, unsigned int type)
                return error;
        }
 
-       percpu_down_read_preempt_disable(&file_rwsem);
+       percpu_down_read(&file_rwsem);
        spin_lock(&ctx->flc_lock);
 
        time_out_leases(inode, &dispose);
@@ -1512,13 +1512,13 @@ restart:
        locks_insert_block(fl, new_fl);
        trace_break_lease_block(inode, new_fl);
        spin_unlock(&ctx->flc_lock);
-       percpu_up_read_preempt_enable(&file_rwsem);
+       percpu_up_read(&file_rwsem);
 
        locks_dispose_list(&dispose);
        error = wait_event_interruptible_timeout(new_fl->fl_wait,
                                                !new_fl->fl_next, break_time);
 
-       percpu_down_read_preempt_disable(&file_rwsem);
+       percpu_down_read(&file_rwsem);
        spin_lock(&ctx->flc_lock);
        trace_break_lease_unblock(inode, new_fl);
        locks_delete_block(new_fl);
@@ -1535,7 +1535,7 @@ restart:
        }
 out:
        spin_unlock(&ctx->flc_lock);
-       percpu_up_read_preempt_enable(&file_rwsem);
+       percpu_up_read(&file_rwsem);
        locks_dispose_list(&dispose);
        locks_free_lock(new_fl);
        return error;
@@ -1609,7 +1609,7 @@ int fcntl_getlease(struct file *filp)
 
        ctx = smp_load_acquire(&inode->i_flctx);
        if (ctx && !list_empty_careful(&ctx->flc_lease)) {
-               percpu_down_read_preempt_disable(&file_rwsem);
+               percpu_down_read(&file_rwsem);
                spin_lock(&ctx->flc_lock);
                time_out_leases(inode, &dispose);
                list_for_each_entry(fl, &ctx->flc_lease, fl_list) {
@@ -1619,7 +1619,7 @@ int fcntl_getlease(struct file *filp)
                        break;
                }
                spin_unlock(&ctx->flc_lock);
-               percpu_up_read_preempt_enable(&file_rwsem);
+               percpu_up_read(&file_rwsem);
 
                locks_dispose_list(&dispose);
        }
@@ -1694,7 +1694,7 @@ generic_add_lease(struct file *filp, long arg, struct file_lock **flp, void **pr
                return -EINVAL;
        }
 
-       percpu_down_read_preempt_disable(&file_rwsem);
+       percpu_down_read(&file_rwsem);
        spin_lock(&ctx->flc_lock);
        time_out_leases(inode, &dispose);
        error = check_conflicting_open(dentry, arg, lease->fl_flags);
@@ -1765,7 +1765,7 @@ out_setup:
                lease->fl_lmops->lm_setup(lease, priv);
 out:
        spin_unlock(&ctx->flc_lock);
-       percpu_up_read_preempt_enable(&file_rwsem);
+       percpu_up_read(&file_rwsem);
        locks_dispose_list(&dispose);
        if (is_deleg)
                inode_unlock(inode);
@@ -1788,7 +1788,7 @@ static int generic_delete_lease(struct file *filp, void *owner)
                return error;
        }
 
-       percpu_down_read_preempt_disable(&file_rwsem);
+       percpu_down_read(&file_rwsem);
        spin_lock(&ctx->flc_lock);
        list_for_each_entry(fl, &ctx->flc_lease, fl_list) {
                if (fl->fl_file == filp &&
@@ -1801,7 +1801,7 @@ static int generic_delete_lease(struct file *filp, void *owner)
        if (victim)
                error = fl->fl_lmops->lm_change(victim, F_UNLCK, &dispose);
        spin_unlock(&ctx->flc_lock);
-       percpu_up_read_preempt_enable(&file_rwsem);
+       percpu_up_read(&file_rwsem);
        locks_dispose_list(&dispose);
        return error;
 }
@@ -2532,13 +2532,13 @@ locks_remove_lease(struct file *filp, struct file_lock_context *ctx)
        if (list_empty(&ctx->flc_lease))
                return;
 
-       percpu_down_read_preempt_disable(&file_rwsem);
+       percpu_down_read(&file_rwsem);
        spin_lock(&ctx->flc_lock);
        list_for_each_entry_safe(fl, tmp, &ctx->flc_lease, fl_list)
                if (filp == fl->fl_file)
                        lease_modify(fl, F_UNLCK, &dispose);
        spin_unlock(&ctx->flc_lock);
-       percpu_up_read_preempt_enable(&file_rwsem);
+       percpu_up_read(&file_rwsem);
 
        locks_dispose_list(&dispose);
 }
index d2ab786..38db133 100644 (file)
@@ -1682,7 +1682,7 @@ static struct dentry *lookup_slow(const struct qstr *name,
 {
        struct dentry *dentry = ERR_PTR(-ENOENT), *old;
        struct inode *inode = dir->d_inode;
-       DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+       DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
 
        inode_lock_shared(inode);
        /* Don't go there if it's already dead */
@@ -3164,7 +3164,7 @@ static int lookup_open(struct nameidata *nd, struct path *path,
        struct dentry *dentry;
        int error, create_error = 0;
        umode_t mode = op->mode;
-       DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+       DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
 
        if (unlikely(IS_DEADDIR(dir_inode)))
                return -ENOENT;
index f4e439b..d2d3449 100644 (file)
@@ -14,6 +14,7 @@
 #include <linux/mnt_namespace.h>
 #include <linux/user_namespace.h>
 #include <linux/namei.h>
+#include <linux/delay.h>
 #include <linux/security.h>
 #include <linux/idr.h>
 #include <linux/init.h>                /* init_rootfs */
@@ -358,8 +359,11 @@ int __mnt_want_write(struct vfsmount *m)
         * incremented count after it has set MNT_WRITE_HOLD.
         */
        smp_mb();
-       while (ACCESS_ONCE(mnt->mnt.mnt_flags) & MNT_WRITE_HOLD)
-               cpu_relax();
+       while (ACCESS_ONCE(mnt->mnt.mnt_flags) & MNT_WRITE_HOLD) {
+               preempt_enable();
+               cpu_chill();
+               preempt_disable();
+       }
        /*
         * After the slowpath clears MNT_WRITE_HOLD, mnt_is_readonly will
         * be set to match its requirements. So we must not load that until
index 0140396..d688f89 100644 (file)
@@ -160,11 +160,11 @@ again:
                sp = state->owner;
                /* Block nfs4_proc_unlck */
                mutex_lock(&sp->so_delegreturn_mutex);
-               seq = raw_seqcount_begin(&sp->so_reclaim_seqcount);
+               seq = read_seqbegin(&sp->so_reclaim_seqlock);
                err = nfs4_open_delegation_recall(ctx, state, stateid, type);
                if (!err)
                        err = nfs_delegation_claim_locks(state, stateid);
-               if (!err && read_seqcount_retry(&sp->so_reclaim_seqcount, seq))
+               if (!err && read_seqretry(&sp->so_reclaim_seqlock, seq))
                        err = -EAGAIN;
                mutex_unlock(&sp->so_delegreturn_mutex);
                put_nfs_open_context(ctx);
index d405b5a..b38fc00 100644 (file)
@@ -487,7 +487,7 @@ static
 void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry)
 {
        struct qstr filename = QSTR_INIT(entry->name, entry->len);
-       DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+       DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
        struct dentry *dentry;
        struct dentry *alias;
        struct inode *dir = d_inode(parent);
@@ -1503,7 +1503,7 @@ int nfs_atomic_open(struct inode *dir, struct dentry *dentry,
                    struct file *file, unsigned open_flags,
                    umode_t mode, int *opened)
 {
-       DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+       DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
        struct nfs_open_context *ctx;
        struct dentry *res;
        struct iattr attr = { .ia_valid = ATTR_OPEN };
@@ -1818,7 +1818,11 @@ int nfs_rmdir(struct inode *dir, struct dentry *dentry)
 
        trace_nfs_rmdir_enter(dir, dentry);
        if (d_really_is_positive(dentry)) {
+#ifdef CONFIG_PREEMPT_RT_BASE
+               down(&NFS_I(d_inode(dentry))->rmdir_sem);
+#else
                down_write(&NFS_I(d_inode(dentry))->rmdir_sem);
+#endif
                error = NFS_PROTO(dir)->rmdir(dir, &dentry->d_name);
                /* Ensure the VFS deletes this inode */
                switch (error) {
@@ -1828,7 +1832,11 @@ int nfs_rmdir(struct inode *dir, struct dentry *dentry)
                case -ENOENT:
                        nfs_dentry_handle_enoent(dentry);
                }
+#ifdef CONFIG_PREEMPT_RT_BASE
+               up(&NFS_I(d_inode(dentry))->rmdir_sem);
+#else
                up_write(&NFS_I(d_inode(dentry))->rmdir_sem);
+#endif
        } else
                error = NFS_PROTO(dir)->rmdir(dir, &dentry->d_name);
        trace_nfs_rmdir_exit(dir, dentry, error);
index 851274b..f8dd515 100644 (file)
@@ -1958,7 +1958,11 @@ static void init_once(void *foo)
        nfsi->nrequests = 0;
        nfsi->commit_info.ncommit = 0;
        atomic_set(&nfsi->commit_info.rpcs_out, 0);
+#ifdef CONFIG_PREEMPT_RT_BASE
+       sema_init(&nfsi->rmdir_sem, 1);
+#else
        init_rwsem(&nfsi->rmdir_sem);
+#endif
        nfs4_init_once(nfsi);
 }
 
index c719389..5dcaae3 100644 (file)
@@ -111,7 +111,7 @@ struct nfs4_state_owner {
        unsigned long        so_flags;
        struct list_head     so_states;
        struct nfs_seqid_counter so_seqid;
-       seqcount_t           so_reclaim_seqcount;
+       seqlock_t            so_reclaim_seqlock;
        struct mutex         so_delegreturn_mutex;
 };
 
index 4e2f18c..b1448b2 100644 (file)
@@ -2705,7 +2705,7 @@ static int _nfs4_open_and_get_state(struct nfs4_opendata *opendata,
        unsigned int seq;
        int ret;
 
-       seq = raw_seqcount_begin(&sp->so_reclaim_seqcount);
+       seq = raw_seqcount_begin(&sp->so_reclaim_seqlock.seqcount);
 
        ret = _nfs4_proc_open(opendata);
        if (ret != 0)
@@ -2743,7 +2743,7 @@ static int _nfs4_open_and_get_state(struct nfs4_opendata *opendata,
 
        if (d_inode(dentry) == state->inode) {
                nfs_inode_attach_open_context(ctx);
-               if (read_seqcount_retry(&sp->so_reclaim_seqcount, seq))
+               if (read_seqretry(&sp->so_reclaim_seqlock, seq))
                        nfs4_schedule_stateid_recovery(server, state);
        }
 out:
index 4e63dae..57facf9 100644 (file)
@@ -492,7 +492,7 @@ nfs4_alloc_state_owner(struct nfs_server *server,
        nfs4_init_seqid_counter(&sp->so_seqid);
        atomic_set(&sp->so_count, 1);
        INIT_LIST_HEAD(&sp->so_lru);
-       seqcount_init(&sp->so_reclaim_seqcount);
+       seqlock_init(&sp->so_reclaim_seqlock);
        mutex_init(&sp->so_delegreturn_mutex);
        return sp;
 }
@@ -1522,8 +1522,12 @@ static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs
         * recovering after a network partition or a reboot from a
         * server that doesn't support a grace period.
         */
+#ifdef CONFIG_PREEMPT_RT_FULL
+       write_seqlock(&sp->so_reclaim_seqlock);
+#else
+       write_seqcount_begin(&sp->so_reclaim_seqlock.seqcount);
+#endif
        spin_lock(&sp->so_lock);
-       raw_write_seqcount_begin(&sp->so_reclaim_seqcount);
 restart:
        list_for_each_entry(state, &sp->so_states, open_states) {
                if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
@@ -1592,14 +1596,20 @@ restart:
                spin_lock(&sp->so_lock);
                goto restart;
        }
-       raw_write_seqcount_end(&sp->so_reclaim_seqcount);
        spin_unlock(&sp->so_lock);
+#ifdef CONFIG_PREEMPT_RT_FULL
+       write_sequnlock(&sp->so_reclaim_seqlock);
+#else
+       write_seqcount_end(&sp->so_reclaim_seqlock.seqcount);
+#endif
        return 0;
 out_err:
        nfs4_put_open_state(state);
-       spin_lock(&sp->so_lock);
-       raw_write_seqcount_end(&sp->so_reclaim_seqcount);
-       spin_unlock(&sp->so_lock);
+#ifdef CONFIG_PREEMPT_RT_FULL
+       write_sequnlock(&sp->so_reclaim_seqlock);
+#else
+       write_seqcount_end(&sp->so_reclaim_seqlock.seqcount);
+#endif
        return status;
 }
 
index 191aa57..58990c8 100644 (file)
@@ -12,7 +12,7 @@
 #include <linux/sunrpc/clnt.h>
 #include <linux/nfs_fs.h>
 #include <linux/sched.h>
-#include <linux/wait.h>
+#include <linux/swait.h>
 #include <linux/namei.h>
 #include <linux/fsnotify.h>
 
@@ -51,6 +51,29 @@ static void nfs_async_unlink_done(struct rpc_task *task, void *calldata)
                rpc_restart_call_prepare(task);
 }
 
+#ifdef CONFIG_PREEMPT_RT_BASE
+static void nfs_down_anon(struct semaphore *sema)
+{
+       down(sema);
+}
+
+static void nfs_up_anon(struct semaphore *sema)
+{
+       up(sema);
+}
+
+#else
+static void nfs_down_anon(struct rw_semaphore *rwsem)
+{
+       down_read_non_owner(rwsem);
+}
+
+static void nfs_up_anon(struct rw_semaphore *rwsem)
+{
+       up_read_non_owner(rwsem);
+}
+#endif
+
 /**
  * nfs_async_unlink_release - Release the sillydelete data.
  * @task: rpc_task of the sillydelete
@@ -64,7 +87,7 @@ static void nfs_async_unlink_release(void *calldata)
        struct dentry *dentry = data->dentry;
        struct super_block *sb = dentry->d_sb;
 
-       up_read_non_owner(&NFS_I(d_inode(dentry->d_parent))->rmdir_sem);
+       nfs_up_anon(&NFS_I(d_inode(dentry->d_parent))->rmdir_sem);
        d_lookup_done(dentry);
        nfs_free_unlinkdata(data);
        dput(dentry);
@@ -117,10 +140,10 @@ static int nfs_call_unlink(struct dentry *dentry, struct nfs_unlinkdata *data)
        struct inode *dir = d_inode(dentry->d_parent);
        struct dentry *alias;
 
-       down_read_non_owner(&NFS_I(dir)->rmdir_sem);
+       nfs_down_anon(&NFS_I(dir)->rmdir_sem);
        alias = d_alloc_parallel(dentry->d_parent, &data->args.name, &data->wq);
        if (IS_ERR(alias)) {
-               up_read_non_owner(&NFS_I(dir)->rmdir_sem);
+               nfs_up_anon(&NFS_I(dir)->rmdir_sem);
                return 0;
        }
        if (!d_in_lookup(alias)) {
@@ -142,7 +165,7 @@ static int nfs_call_unlink(struct dentry *dentry, struct nfs_unlinkdata *data)
                        ret = 0;
                spin_unlock(&alias->d_lock);
                dput(alias);
-               up_read_non_owner(&NFS_I(dir)->rmdir_sem);
+               nfs_up_anon(&NFS_I(dir)->rmdir_sem);
                /*
                 * If we'd displaced old cached devname, free it.  At that
                 * point dentry is definitely not a root, so we won't need
@@ -182,7 +205,7 @@ nfs_async_unlink(struct dentry *dentry, const struct qstr *name)
                goto out_free_name;
        }
        data->res.dir_attr = &data->dir_attr;
-       init_waitqueue_head(&data->wq);
+       init_swait_queue_head(&data->wq);
 
        status = -EBUSY;
        spin_lock(&dentry->d_lock);
index fe251f1..e89da4f 100644 (file)
@@ -92,13 +92,13 @@ static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate)
                        ofs = 0;
                        if (file_ofs < init_size)
                                ofs = init_size - file_ofs;
-                       local_irq_save(flags);
+                       local_irq_save_nort(flags);
                        kaddr = kmap_atomic(page);
                        memset(kaddr + bh_offset(bh) + ofs, 0,
                                        bh->b_size - ofs);
                        flush_dcache_page(page);
                        kunmap_atomic(kaddr);
-                       local_irq_restore(flags);
+                       local_irq_restore_nort(flags);
                }
        } else {
                clear_buffer_uptodate(bh);
@@ -107,8 +107,7 @@ static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate)
                                "0x%llx.", (unsigned long long)bh->b_blocknr);
        }
        first = page_buffers(page);
-       local_irq_save(flags);
-       bit_spin_lock(BH_Uptodate_Lock, &first->b_state);
+       flags = bh_uptodate_lock_irqsave(first);
        clear_buffer_async_read(bh);
        unlock_buffer(bh);
        tmp = bh;
@@ -123,8 +122,7 @@ static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate)
                }
                tmp = tmp->b_this_page;
        } while (tmp != bh);
-       bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
-       local_irq_restore(flags);
+       bh_uptodate_unlock_irqrestore(first, flags);
        /*
         * If none of the buffers had errors then we can set the page uptodate,
         * but we first have to perform the post read mst fixups, if the
@@ -145,13 +143,13 @@ static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate)
                recs = PAGE_SIZE / rec_size;
                /* Should have been verified before we got here... */
                BUG_ON(!recs);
-               local_irq_save(flags);
+               local_irq_save_nort(flags);
                kaddr = kmap_atomic(page);
                for (i = 0; i < recs; i++)
                        post_read_mst_fixup((NTFS_RECORD*)(kaddr +
                                        i * rec_size), rec_size);
                kunmap_atomic(kaddr);
-               local_irq_restore(flags);
+               local_irq_restore_nort(flags);
                flush_dcache_page(page);
                if (likely(page_uptodate && !PageError(page)))
                        SetPageUptodate(page);
@@ -159,9 +157,7 @@ static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate)
        unlock_page(page);
        return;
 still_busy:
-       bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
-       local_irq_restore(flags);
-       return;
+       bh_uptodate_unlock_irqrestore(first, flags);
 }
 
 /**
index 1649be6..8524440 100644 (file)
@@ -1847,7 +1847,7 @@ bool proc_fill_cache(struct file *file, struct dir_context *ctx,
 
        child = d_hash_and_lookup(dir, &qname);
        if (!child) {
-               DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+               DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
                child = d_alloc_parallel(dir, &qname, &wq);
                if (IS_ERR(child))
                        goto end_instantiate;
index 191573a..2a3f0c8 100644 (file)
@@ -684,7 +684,7 @@ static bool proc_sys_fill_cache(struct file *file,
 
        child = d_lookup(dir, &qname);
        if (!child) {
-               DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+               DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
                child = d_alloc_parallel(dir, &qname, &wq);
                if (IS_ERR(child))
                        return false;
index 23a9c28..6a73c4f 100644 (file)
@@ -10,6 +10,7 @@
 #include <linux/slab.h>
 #include <linux/percpu.h>
 #include <linux/buffer_head.h>
+#include <linux/locallock.h>
 
 #include "squashfs_fs.h"
 #include "squashfs_fs_sb.h"
@@ -25,6 +26,8 @@ struct squashfs_stream {
        void            *stream;
 };
 
+static DEFINE_LOCAL_IRQ_LOCK(stream_lock);
+
 void *squashfs_decompressor_create(struct squashfs_sb_info *msblk,
                                                void *comp_opts)
 {
@@ -79,10 +82,15 @@ int squashfs_decompress(struct squashfs_sb_info *msblk, struct buffer_head **bh,
 {
        struct squashfs_stream __percpu *percpu =
                        (struct squashfs_stream __percpu *) msblk->stream;
-       struct squashfs_stream *stream = get_cpu_ptr(percpu);
-       int res = msblk->decompressor->decompress(msblk, stream->stream, bh, b,
-               offset, length, output);
-       put_cpu_ptr(stream);
+       struct squashfs_stream *stream;
+       int res;
+
+       stream = get_locked_ptr(stream_lock, percpu);
+
+       res = msblk->decompressor->decompress(msblk, stream->stream, bh, b,
+                       offset, length, output);
+
+       put_locked_ptr(stream_lock, stream);
 
        if (res < 0)
                ERROR("%s decompression failed, data probably corrupt\n",
index ab8dd15..5580853 100644 (file)
@@ -471,7 +471,10 @@ static int do_timerfd_settime(int ufd, int flags,
                                break;
                }
                spin_unlock_irq(&ctx->wqh.lock);
-               cpu_relax();
+               if (isalarm(ctx))
+                       hrtimer_wait_for_timer(&ctx->t.alarm.timer);
+               else
+                       hrtimer_wait_for_timer(&ctx->t.tmr);
        }
 
        /*
index f3acecf..c30dbde 100644 (file)
@@ -112,8 +112,7 @@ xfs_finish_page_writeback(
        ASSERT(bvec->bv_offset + bvec->bv_len <= PAGE_SIZE);
        ASSERT((bvec->bv_len & (i_blocksize(inode) - 1)) == 0);
 
-       local_irq_save(flags);
-       bit_spin_lock(BH_Uptodate_Lock, &head->b_state);
+       flags = bh_uptodate_lock_irqsave(head);
        do {
                if (off >= bvec->bv_offset &&
                    off < bvec->bv_offset + bvec->bv_len) {
@@ -136,8 +135,7 @@ xfs_finish_page_writeback(
                }
                off += bh->b_size;
        } while ((bh = bh->b_this_page) != head);
-       bit_spin_unlock(BH_Uptodate_Lock, &head->b_state);
-       local_irq_restore(flags);
+       bh_uptodate_unlock_irqrestore(head, flags);
 
        if (!busy)
                end_page_writeback(bvec->bv_page);
index e861a24..b5c97d3 100644 (file)
 
 #define acpi_cache_t                        struct kmem_cache
 #define acpi_spinlock                       spinlock_t *
+#define acpi_raw_spinlock              raw_spinlock_t *
 #define acpi_cpu_flags                      unsigned long
 
 /* Use native linux version of acpi_os_allocate_zeroed */
 #define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_get_thread_id
 #define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_create_lock
 
+#define acpi_os_create_raw_lock(__handle)                      \
+({                                                             \
+        raw_spinlock_t *lock = ACPI_ALLOCATE(sizeof(*lock));   \
+                                                               \
+        if (lock) {                                            \
+               *(__handle) = lock;                             \
+               raw_spin_lock_init(*(__handle));                \
+        }                                                      \
+        lock ? AE_OK : AE_NO_MEMORY;                           \
+ })
+
+#define acpi_os_delete_raw_lock(__handle)      kfree(__handle)
+
+
 /*
  * OSL interfaces used by debugger/disassembler
  */
index 89f079d..56553e2 100644 (file)
@@ -216,6 +216,20 @@ void __warn(const char *file, int line, void *caller, unsigned taint,
 # define WARN_ON_SMP(x)                        ({0;})
 #endif
 
+#ifdef CONFIG_PREEMPT_RT_BASE
+# define BUG_ON_RT(c)                  BUG_ON(c)
+# define BUG_ON_NONRT(c)               do { } while (0)
+# define WARN_ON_RT(condition)         WARN_ON(condition)
+# define WARN_ON_NONRT(condition)      do { } while (0)
+# define WARN_ON_ONCE_NONRT(condition) do { } while (0)
+#else
+# define BUG_ON_RT(c)                  do { } while (0)
+# define BUG_ON_NONRT(c)               BUG_ON(c)
+# define WARN_ON_RT(condition)         do { } while (0)
+# define WARN_ON_NONRT(condition)      WARN_ON(condition)
+# define WARN_ON_ONCE_NONRT(condition) WARN_ON_ONCE(condition)
+#endif
+
 #endif /* __ASSEMBLY__ */
 
 #endif
index 535ab2e..cfc2468 100644 (file)
@@ -209,7 +209,7 @@ static inline u16 blk_mq_unique_tag_to_tag(u32 unique_tag)
        return unique_tag & BLK_MQ_UNIQUE_TAG_MASK;
 }
 
-
+void __blk_mq_complete_request_remote_work(struct work_struct *work);
 int blk_mq_request_started(struct request *rq);
 void blk_mq_start_request(struct request *rq);
 void blk_mq_end_request(struct request *rq, int error);
index b5d23bc..5d39358 100644 (file)
@@ -24,6 +24,7 @@
 #include <linux/rcupdate.h>
 #include <linux/percpu-refcount.h>
 #include <linux/scatterlist.h>
+#include <linux/swork.h>
 
 struct module;
 struct scsi_ioctl_command;
@@ -89,6 +90,7 @@ struct request {
        struct list_head queuelist;
        union {
                struct call_single_data csd;
+               struct work_struct work;
                u64 fifo_time;
        };
 
@@ -477,6 +479,7 @@ struct request_queue {
 #endif
        struct rcu_head         rcu_head;
        wait_queue_head_t       mq_freeze_wq;
+       struct swork_event      mq_pcpu_wake;
        struct percpu_ref       q_usage_counter;
        struct list_head        all_q_node;
 
index 8fdcb78..d07dbee 100644 (file)
@@ -3,6 +3,39 @@
 
 #include <linux/preempt.h>
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+
+extern void __local_bh_disable(void);
+extern void _local_bh_enable(void);
+extern void __local_bh_enable(void);
+
+static inline void local_bh_disable(void)
+{
+       __local_bh_disable();
+}
+
+static inline void __local_bh_disable_ip(unsigned long ip, unsigned int cnt)
+{
+       __local_bh_disable();
+}
+
+static inline void local_bh_enable(void)
+{
+       __local_bh_enable();
+}
+
+static inline void __local_bh_enable_ip(unsigned long ip, unsigned int cnt)
+{
+       __local_bh_enable();
+}
+
+static inline void local_bh_enable_ip(unsigned long ip)
+{
+       __local_bh_enable();
+}
+
+#else
+
 #ifdef CONFIG_TRACE_IRQFLAGS
 extern void __local_bh_disable_ip(unsigned long ip, unsigned int cnt);
 #else
@@ -30,5 +63,6 @@ static inline void local_bh_enable(void)
 {
        __local_bh_enable_ip(_THIS_IP_, SOFTIRQ_DISABLE_OFFSET);
 }
+#endif
 
 #endif /* _LINUX_BH_H */
index 4431ea2..0744157 100644 (file)
@@ -75,8 +75,50 @@ struct buffer_head {
        struct address_space *b_assoc_map;      /* mapping this buffer is
                                                   associated with */
        atomic_t b_count;               /* users using this buffer_head */
+#ifdef CONFIG_PREEMPT_RT_BASE
+       spinlock_t b_uptodate_lock;
+#if IS_ENABLED(CONFIG_JBD2)
+       spinlock_t b_state_lock;
+       spinlock_t b_journal_head_lock;
+#endif
+#endif
 };
 
+static inline unsigned long bh_uptodate_lock_irqsave(struct buffer_head *bh)
+{
+       unsigned long flags;
+
+#ifndef CONFIG_PREEMPT_RT_BASE
+       local_irq_save(flags);
+       bit_spin_lock(BH_Uptodate_Lock, &bh->b_state);
+#else
+       spin_lock_irqsave(&bh->b_uptodate_lock, flags);
+#endif
+       return flags;
+}
+
+static inline void
+bh_uptodate_unlock_irqrestore(struct buffer_head *bh, unsigned long flags)
+{
+#ifndef CONFIG_PREEMPT_RT_BASE
+       bit_spin_unlock(BH_Uptodate_Lock, &bh->b_state);
+       local_irq_restore(flags);
+#else
+       spin_unlock_irqrestore(&bh->b_uptodate_lock, flags);
+#endif
+}
+
+static inline void buffer_head_init_locks(struct buffer_head *bh)
+{
+#ifdef CONFIG_PREEMPT_RT_BASE
+       spin_lock_init(&bh->b_uptodate_lock);
+#if IS_ENABLED(CONFIG_JBD2)
+       spin_lock_init(&bh->b_state_lock);
+       spin_lock_init(&bh->b_journal_head_lock);
+#endif
+#endif
+}
+
 /*
  * macro tricks to expand the set_buffer_foo(), clear_buffer_foo()
  * and buffer_foo() functions.
index 8875175..703ebb3 100644 (file)
@@ -17,6 +17,7 @@
 #include <linux/percpu-rwsem.h>
 #include <linux/workqueue.h>
 #include <linux/bpf-cgroup.h>
+#include <linux/swork.h>
 
 #ifdef CONFIG_CGROUPS
 
@@ -139,6 +140,7 @@ struct cgroup_subsys_state {
        /* percpu_ref killing and RCU release */
        struct rcu_head rcu_head;
        struct work_struct destroy_work;
+       struct swork_event destroy_swork;
 };
 
 /*
index 5d5aaae..3bca159 100644 (file)
@@ -7,8 +7,7 @@
  * Atomic wait-for-completion handler data structures.
  * See kernel/sched/completion.c for details.
  */
-
-#include <linux/wait.h>
+#include <linux/swait.h>
 
 /*
  * struct completion - structure used to maintain state for a "completion"
  */
 struct completion {
        unsigned int done;
-       wait_queue_head_t wait;
+       struct swait_queue_head wait;
 };
 
 #define COMPLETION_INITIALIZER(work) \
-       { 0, __WAIT_QUEUE_HEAD_INITIALIZER((work).wait) }
+       { 0, __SWAIT_QUEUE_HEAD_INITIALIZER((work).wait) }
 
 #define COMPLETION_INITIALIZER_ONSTACK(work) \
        ({ init_completion(&work); work; })
@@ -73,7 +72,7 @@ struct completion {
 static inline void init_completion(struct completion *x)
 {
        x->done = 0;
-       init_waitqueue_head(&x->wait);
+       init_swait_queue_head(&x->wait);
 }
 
 /**
index 71935db..1185ca9 100644 (file)
@@ -200,6 +200,8 @@ extern void get_online_cpus(void);
 extern void put_online_cpus(void);
 extern void cpu_hotplug_disable(void);
 extern void cpu_hotplug_enable(void);
+extern void pin_current_cpu(void);
+extern void unpin_current_cpu(void);
 #define hotcpu_notifier(fn, pri)       cpu_notifier(fn, pri)
 #define __hotcpu_notifier(fn, pri)     __cpu_notifier(fn, pri)
 #define register_hotcpu_notifier(nb)   register_cpu_notifier(nb)
@@ -217,6 +219,8 @@ static inline void cpu_hotplug_done(void) {}
 #define put_online_cpus()      do { } while (0)
 #define cpu_hotplug_disable()  do { } while (0)
 #define cpu_hotplug_enable()   do { } while (0)
+static inline void pin_current_cpu(void) { }
+static inline void unpin_current_cpu(void) { }
 #define hotcpu_notifier(fn, pri)       do { (void)(fn); } while (0)
 #define __hotcpu_notifier(fn, pri)     do { (void)(fn); } while (0)
 /* These aren't inline functions due to a GCC bug. */
index 014d7f9..05b7100 100644 (file)
@@ -11,6 +11,7 @@
 #include <linux/rcupdate.h>
 #include <linux/lockref.h>
 #include <linux/stringhash.h>
+#include <linux/wait.h>
 
 struct path;
 struct vfsmount;
@@ -100,7 +101,7 @@ struct dentry {
 
        union {
                struct list_head d_lru;         /* LRU list */
-               wait_queue_head_t *d_wait;      /* in-lookup ones only */
+               struct swait_queue_head *d_wait;        /* in-lookup ones only */
        };
        struct list_head d_child;       /* child of parent list */
        struct list_head d_subdirs;     /* our children */
@@ -232,7 +233,7 @@ extern void d_set_d_op(struct dentry *dentry, const struct dentry_operations *op
 extern struct dentry * d_alloc(struct dentry *, const struct qstr *);
 extern struct dentry * d_alloc_pseudo(struct super_block *, const struct qstr *);
 extern struct dentry * d_alloc_parallel(struct dentry *, const struct qstr *,
-                                       wait_queue_head_t *);
+                                       struct swait_queue_head *);
 extern struct dentry * d_splice_alias(struct inode *, struct dentry *);
 extern struct dentry * d_add_ci(struct dentry *, struct inode *, struct qstr *);
 extern struct dentry * d_exact_alias(struct dentry *, struct inode *);
index a6ecb34..37caab3 100644 (file)
@@ -52,4 +52,10 @@ static inline void ssleep(unsigned int seconds)
        msleep(seconds * 1000);
 }
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+extern void cpu_chill(void);
+#else
+# define cpu_chill()   cpu_relax()
+#endif
+
 #endif /* defined(_LINUX_DELAY_H) */
index 096c9c7..12afe0a 100644 (file)
@@ -714,7 +714,7 @@ struct inode {
                struct block_device     *i_bdev;
                struct cdev             *i_cdev;
                char                    *i_link;
-               unsigned                i_dir_seq;
+               unsigned                __i_dir_seq;
        };
 
        __u32                   i_generation;
index bb3f329..a117a33 100644 (file)
@@ -7,6 +7,7 @@
 #include <linux/mm.h>
 #include <linux/uaccess.h>
 #include <linux/hardirq.h>
+#include <linux/sched.h>
 
 #include <asm/cacheflush.h>
 
@@ -65,7 +66,7 @@ static inline void kunmap(struct page *page)
 
 static inline void *kmap_atomic(struct page *page)
 {
-       preempt_disable();
+       preempt_disable_nort();
        pagefault_disable();
        return page_address(page);
 }
@@ -74,7 +75,7 @@ static inline void *kmap_atomic(struct page *page)
 static inline void __kunmap_atomic(void *addr)
 {
        pagefault_enable();
-       preempt_enable();
+       preempt_enable_nort();
 }
 
 #define kmap_atomic_pfn(pfn)   kmap_atomic(pfn_to_page(pfn))
@@ -86,32 +87,51 @@ static inline void __kunmap_atomic(void *addr)
 
 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32)
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 DECLARE_PER_CPU(int, __kmap_atomic_idx);
+#endif
 
 static inline int kmap_atomic_idx_push(void)
 {
+#ifndef CONFIG_PREEMPT_RT_FULL
        int idx = __this_cpu_inc_return(__kmap_atomic_idx) - 1;
 
-#ifdef CONFIG_DEBUG_HIGHMEM
+# ifdef CONFIG_DEBUG_HIGHMEM
        WARN_ON_ONCE(in_irq() && !irqs_disabled());
        BUG_ON(idx >= KM_TYPE_NR);
-#endif
+# endif
        return idx;
+#else
+       current->kmap_idx++;
+       BUG_ON(current->kmap_idx > KM_TYPE_NR);
+       return current->kmap_idx - 1;
+#endif
 }
 
 static inline int kmap_atomic_idx(void)
 {
+#ifndef CONFIG_PREEMPT_RT_FULL
        return __this_cpu_read(__kmap_atomic_idx) - 1;
+#else
+       return current->kmap_idx - 1;
+#endif
 }
 
 static inline void kmap_atomic_idx_pop(void)
 {
-#ifdef CONFIG_DEBUG_HIGHMEM
+#ifndef CONFIG_PREEMPT_RT_FULL
+# ifdef CONFIG_DEBUG_HIGHMEM
        int idx = __this_cpu_dec_return(__kmap_atomic_idx);
 
        BUG_ON(idx < 0);
-#else
+# else
        __this_cpu_dec(__kmap_atomic_idx);
+# endif
+#else
+       current->kmap_idx--;
+# ifdef CONFIG_DEBUG_HIGHMEM
+       BUG_ON(current->kmap_idx < 0);
+# endif
 #endif
 }
 
index 5ae70d2..cf423f1 100644 (file)
@@ -87,6 +87,9 @@ enum hrtimer_restart {
  * @function:  timer expiry callback function
  * @base:      pointer to the timer base (per cpu and per clock)
  * @state:     state information (See bit values above)
+ * @cb_entry:  list entry to defer timers from hardirq context
+ * @irqsafe:   timer can run in hardirq context
+ * @praecox:   timer expiry time if expired at the time of programming
  * @is_rel:    Set if the timer was armed relative
  * @start_pid:  timer statistics field to store the pid of the task which
  *             started the timer
@@ -103,6 +106,11 @@ struct hrtimer {
        enum hrtimer_restart            (*function)(struct hrtimer *);
        struct hrtimer_clock_base       *base;
        u8                              state;
+       struct list_head                cb_entry;
+       int                             irqsafe;
+#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
+       ktime_t                         praecox;
+#endif
        u8                              is_rel;
 #ifdef CONFIG_TIMER_STATS
        int                             start_pid;
@@ -123,11 +131,7 @@ struct hrtimer_sleeper {
        struct task_struct *task;
 };
 
-#ifdef CONFIG_64BIT
 # define HRTIMER_CLOCK_BASE_ALIGN      64
-#else
-# define HRTIMER_CLOCK_BASE_ALIGN      32
-#endif
 
 /**
  * struct hrtimer_clock_base - the timer base for a specific clock
@@ -136,6 +140,7 @@ struct hrtimer_sleeper {
  *                     timer to a base on another cpu.
  * @clockid:           clock id for per_cpu support
  * @active:            red black tree root node for the active timers
+ * @expired:           list head for deferred timers.
  * @get_time:          function to retrieve the current time of the clock
  * @offset:            offset of this clock to the monotonic base
  */
@@ -144,6 +149,7 @@ struct hrtimer_clock_base {
        int                     index;
        clockid_t               clockid;
        struct timerqueue_head  active;
+       struct list_head        expired;
        ktime_t                 (*get_time)(void);
        ktime_t                 offset;
 } __attribute__((__aligned__(HRTIMER_CLOCK_BASE_ALIGN)));
@@ -187,6 +193,7 @@ struct hrtimer_cpu_base {
        raw_spinlock_t                  lock;
        seqcount_t                      seq;
        struct hrtimer                  *running;
+       struct hrtimer                  *running_soft;
        unsigned int                    cpu;
        unsigned int                    active_bases;
        unsigned int                    clock_was_set_seq;
@@ -203,6 +210,9 @@ struct hrtimer_cpu_base {
        unsigned int                    nr_hangs;
        unsigned int                    max_hang_time;
 #endif
+#ifdef CONFIG_PREEMPT_RT_BASE
+       wait_queue_head_t               wait;
+#endif
        struct hrtimer_clock_base       clock_base[HRTIMER_MAX_CLOCK_BASES];
 } ____cacheline_aligned;
 
@@ -412,6 +422,13 @@ static inline void hrtimer_restart(struct hrtimer *timer)
        hrtimer_start_expires(timer, HRTIMER_MODE_ABS);
 }
 
+/* Softirq preemption could deadlock timer removal */
+#ifdef CONFIG_PREEMPT_RT_BASE
+  extern void hrtimer_wait_for_timer(const struct hrtimer *timer);
+#else
+# define hrtimer_wait_for_timer(timer) do { cpu_relax(); } while (0)
+#endif
+
 /* Query timers: */
 extern ktime_t __hrtimer_get_remaining(const struct hrtimer *timer, bool adjust);
 
@@ -442,9 +459,15 @@ static inline bool hrtimer_is_queued(struct hrtimer *timer)
  * Helper function to check, whether the timer is running the callback
  * function
  */
-static inline int hrtimer_callback_running(struct hrtimer *timer)
+static inline int hrtimer_callback_running(const struct hrtimer *timer)
 {
-       return timer->base->cpu_base->running == timer;
+       if (timer->base->cpu_base->running == timer)
+               return 1;
+#ifdef CONFIG_PREEMPT_RT_BASE
+       if (timer->base->cpu_base->running_soft == timer)
+               return 1;
+#endif
+       return 0;
 }
 
 /* Forward a hrtimer so it expires after now: */
index 083d61e..5899796 100644 (file)
@@ -95,10 +95,14 @@ bool idr_is_empty(struct idr *idp);
  * Each idr_preload() should be matched with an invocation of this
  * function.  See idr_preload() for details.
  */
+#ifdef CONFIG_PREEMPT_RT_FULL
+void idr_preload_end(void);
+#else
 static inline void idr_preload_end(void)
 {
        preempt_enable();
 }
+#endif
 
 /**
  * idr_find - return pointer for given id
index 325f649..a56e263 100644 (file)
@@ -150,6 +150,12 @@ extern struct task_group root_task_group;
 # define INIT_PERF_EVENTS(tsk)
 #endif
 
+#ifdef CONFIG_PREEMPT_RT_BASE
+# define INIT_TIMER_LIST               .posix_timer_list = NULL,
+#else
+# define INIT_TIMER_LIST
+#endif
+
 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
 # define INIT_VTIME(tsk)                                               \
        .vtime_seqcount = SEQCNT_ZERO(tsk.vtime_seqcount),      \
@@ -164,6 +170,7 @@ extern struct task_group root_task_group;
 #ifdef CONFIG_RT_MUTEXES
 # define INIT_RT_MUTEXES(tsk)                                          \
        .pi_waiters = RB_ROOT,                                          \
+       .pi_top_task = NULL,                                            \
        .pi_waiters_leftmost = NULL,
 #else
 # define INIT_RT_MUTEXES(tsk)
@@ -250,6 +257,7 @@ extern struct task_group root_task_group;
        .cpu_timers     = INIT_CPU_TIMERS(tsk.cpu_timers),              \
        .pi_lock        = __RAW_SPIN_LOCK_UNLOCKED(tsk.pi_lock),        \
        .timer_slack_ns = 50000, /* 50 usec default slack */            \
+       INIT_TIMER_LIST                                                 \
        .pids = {                                                       \
                [PIDTYPE_PID]  = INIT_PID_LINK(PIDTYPE_PID),            \
                [PIDTYPE_PGID] = INIT_PID_LINK(PIDTYPE_PGID),           \
index 999b7c3..6e3c032 100644 (file)
@@ -14,6 +14,7 @@
 #include <linux/hrtimer.h>
 #include <linux/kref.h>
 #include <linux/workqueue.h>
+#include <linux/swork.h>
 
 #include <linux/atomic.h>
 #include <asm/ptrace.h>
@@ -62,6 +63,7 @@
  *                interrupt handler after suspending interrupts. For system
  *                wakeup devices users need to implement wakeup detection in
  *                their interrupt handlers.
+ * IRQF_NO_SOFTIRQ_CALL - Do not process softirqs in the irq thread context (RT)
  */
 #define IRQF_SHARED            0x00000080
 #define IRQF_PROBE_SHARED      0x00000100
@@ -75,6 +77,7 @@
 #define IRQF_NO_THREAD         0x00010000
 #define IRQF_EARLY_RESUME      0x00020000
 #define IRQF_COND_SUSPEND      0x00040000
+#define IRQF_NO_SOFTIRQ_CALL   0x00080000
 
 #define IRQF_TIMER             (__IRQF_TIMER | IRQF_NO_SUSPEND | IRQF_NO_THREAD)
 
@@ -197,7 +200,7 @@ extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id);
 #ifdef CONFIG_LOCKDEP
 # define local_irq_enable_in_hardirq() do { } while (0)
 #else
-# define local_irq_enable_in_hardirq() local_irq_enable()
+# define local_irq_enable_in_hardirq() local_irq_enable_nort()
 #endif
 
 extern void disable_irq_nosync(unsigned int irq);
@@ -217,6 +220,7 @@ extern void resume_device_irqs(void);
  * struct irq_affinity_notify - context for notification of IRQ affinity changes
  * @irq:               Interrupt to which notification applies
  * @kref:              Reference count, for internal use
+ * @swork:             Swork item, for internal use
  * @work:              Work item, for internal use
  * @notify:            Function to be called on change.  This will be
  *                     called in process context.
@@ -228,7 +232,11 @@ extern void resume_device_irqs(void);
 struct irq_affinity_notify {
        unsigned int irq;
        struct kref kref;
+#ifdef CONFIG_PREEMPT_RT_BASE
+       struct swork_event swork;
+#else
        struct work_struct work;
+#endif
        void (*notify)(struct irq_affinity_notify *, const cpumask_t *mask);
        void (*release)(struct kref *ref);
 };
@@ -407,9 +415,13 @@ extern int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
                                 bool state);
 
 #ifdef CONFIG_IRQ_FORCED_THREADING
+# ifndef CONFIG_PREEMPT_RT_BASE
 extern bool force_irqthreads;
+# else
+#  define force_irqthreads     (true)
+# endif
 #else
-#define force_irqthreads       (0)
+#define force_irqthreads       (false)
 #endif
 
 #ifndef __ARCH_SET_SOFTIRQ_PENDING
@@ -466,9 +478,10 @@ struct softirq_action
        void    (*action)(struct softirq_action *);
 };
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 asmlinkage void do_softirq(void);
 asmlinkage void __do_softirq(void);
-
+static inline void thread_do_softirq(void) { do_softirq(); }
 #ifdef __ARCH_HAS_DO_SOFTIRQ
 void do_softirq_own_stack(void);
 #else
@@ -477,13 +490,25 @@ static inline void do_softirq_own_stack(void)
        __do_softirq();
 }
 #endif
+#else
+extern void thread_do_softirq(void);
+#endif
 
 extern void open_softirq(int nr, void (*action)(struct softirq_action *));
 extern void softirq_init(void);
 extern void __raise_softirq_irqoff(unsigned int nr);
+#ifdef CONFIG_PREEMPT_RT_FULL
+extern void __raise_softirq_irqoff_ksoft(unsigned int nr);
+#else
+static inline void __raise_softirq_irqoff_ksoft(unsigned int nr)
+{
+       __raise_softirq_irqoff(nr);
+}
+#endif
 
 extern void raise_softirq_irqoff(unsigned int nr);
 extern void raise_softirq(unsigned int nr);
+extern void softirq_check_pending_idle(void);
 
 DECLARE_PER_CPU(struct task_struct *, ksoftirqd);
 
@@ -505,8 +530,9 @@ static inline struct task_struct *this_cpu_ksoftirqd(void)
      to be executed on some cpu at least once after this.
    * If the tasklet is already scheduled, but its execution is still not
      started, it will be executed only once.
-   * If this tasklet is already running on another CPU (or schedule is called
-     from tasklet itself), it is rescheduled for later.
+   * If this tasklet is already running on another CPU, it is rescheduled
+     for later.
+   * Schedule must not be called from the tasklet itself (a lockup occurs)
    * Tasklet is strictly serialized wrt itself, but not
      wrt another tasklets. If client needs some intertask synchronization,
      he makes it with spinlocks.
@@ -531,27 +557,36 @@ struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(1), func, data }
 enum
 {
        TASKLET_STATE_SCHED,    /* Tasklet is scheduled for execution */
-       TASKLET_STATE_RUN       /* Tasklet is running (SMP only) */
+       TASKLET_STATE_RUN,      /* Tasklet is running (SMP only) */
+       TASKLET_STATE_PENDING   /* Tasklet is pending */
 };
 
-#ifdef CONFIG_SMP
+#define TASKLET_STATEF_SCHED   (1 << TASKLET_STATE_SCHED)
+#define TASKLET_STATEF_RUN     (1 << TASKLET_STATE_RUN)
+#define TASKLET_STATEF_PENDING (1 << TASKLET_STATE_PENDING)
+
+#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT_FULL)
 static inline int tasklet_trylock(struct tasklet_struct *t)
 {
        return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
 }
 
+static inline int tasklet_tryunlock(struct tasklet_struct *t)
+{
+       return cmpxchg(&t->state, TASKLET_STATEF_RUN, 0) == TASKLET_STATEF_RUN;
+}
+
 static inline void tasklet_unlock(struct tasklet_struct *t)
 {
        smp_mb__before_atomic();
        clear_bit(TASKLET_STATE_RUN, &(t)->state);
 }
 
-static inline void tasklet_unlock_wait(struct tasklet_struct *t)
-{
-       while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); }
-}
+extern void tasklet_unlock_wait(struct tasklet_struct *t);
+
 #else
 #define tasklet_trylock(t) 1
+#define tasklet_tryunlock(t)   1
 #define tasklet_unlock_wait(t) do { } while (0)
 #define tasklet_unlock(t) do { } while (0)
 #endif
@@ -600,12 +635,7 @@ static inline void tasklet_disable(struct tasklet_struct *t)
        smp_mb();
 }
 
-static inline void tasklet_enable(struct tasklet_struct *t)
-{
-       smp_mb__before_atomic();
-       atomic_dec(&t->count);
-}
-
+extern void tasklet_enable(struct tasklet_struct *t);
 extern void tasklet_kill(struct tasklet_struct *t);
 extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu);
 extern void tasklet_init(struct tasklet_struct *t,
@@ -636,6 +666,12 @@ void tasklet_hrtimer_cancel(struct tasklet_hrtimer *ttimer)
        tasklet_kill(&ttimer->tasklet);
 }
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+extern void softirq_early_init(void);
+#else
+static inline void softirq_early_init(void) { }
+#endif
+
 /*
  * Autoprobing for irqs:
  *
index 39e3254..8ebac94 100644 (file)
@@ -72,6 +72,7 @@ enum irqchip_irq_state;
  * IRQ_IS_POLLED               - Always polled by another interrupt. Exclude
  *                               it from the spurious interrupt detection
  *                               mechanism and from core side polling.
+ * IRQ_NO_SOFTIRQ_CALL         - No softirq processing in the irq thread context (RT)
  * IRQ_DISABLE_UNLAZY          - Disable lazy irq disable
  */
 enum {
@@ -99,13 +100,14 @@ enum {
        IRQ_PER_CPU_DEVID       = (1 << 17),
        IRQ_IS_POLLED           = (1 << 18),
        IRQ_DISABLE_UNLAZY      = (1 << 19),
+       IRQ_NO_SOFTIRQ_CALL     = (1 << 20),
 };
 
 #define IRQF_MODIFY_MASK       \
        (IRQ_TYPE_SENSE_MASK | IRQ_NOPROBE | IRQ_NOREQUEST | \
         IRQ_NOAUTOEN | IRQ_MOVE_PCNTXT | IRQ_LEVEL | IRQ_NO_BALANCING | \
         IRQ_PER_CPU | IRQ_NESTED_THREAD | IRQ_NOTHREAD | IRQ_PER_CPU_DEVID | \
-        IRQ_IS_POLLED | IRQ_DISABLE_UNLAZY)
+        IRQ_IS_POLLED | IRQ_DISABLE_UNLAZY | IRQ_NO_SOFTIRQ_CALL)
 
 #define IRQ_NO_BALANCING_MASK  (IRQ_PER_CPU | IRQ_NO_BALANCING)
 
index 47b9ebd..2543aab 100644 (file)
@@ -16,6 +16,7 @@
 #define IRQ_WORK_BUSY          2UL
 #define IRQ_WORK_FLAGS         3UL
 #define IRQ_WORK_LAZY          4UL /* Doesn't want IPI, wait for tick */
+#define IRQ_WORK_HARD_IRQ      8UL /* Run hard IRQ context, even on RT */
 
 struct irq_work {
        unsigned long flags;
@@ -51,4 +52,10 @@ static inline bool irq_work_needs_cpu(void) { return false; }
 static inline void irq_work_run(void) { }
 #endif
 
+#if defined(CONFIG_IRQ_WORK) && defined(CONFIG_PREEMPT_RT_FULL)
+void irq_work_tick_soft(void);
+#else
+static inline void irq_work_tick_soft(void) { }
+#endif
+
 #endif /* _LINUX_IRQ_WORK_H */
index bb5547a..529da7e 100644 (file)
@@ -67,6 +67,7 @@ struct irq_desc {
        unsigned int            irqs_unhandled;
        atomic_t                threads_handled;
        int                     threads_handled_last;
+       u64                     random_ip;
        raw_spinlock_t          lock;
        struct cpumask          *percpu_enabled;
        const struct cpumask    *percpu_affinity;
index 5dd1272..9b77034 100644 (file)
@@ -25,8 +25,6 @@
 # define trace_softirqs_enabled(p)     ((p)->softirqs_enabled)
 # define trace_hardirq_enter() do { current->hardirq_context++; } while (0)
 # define trace_hardirq_exit()  do { current->hardirq_context--; } while (0)
-# define lockdep_softirq_enter()       do { current->softirq_context++; } while (0)
-# define lockdep_softirq_exit()        do { current->softirq_context--; } while (0)
 # define INIT_TRACE_IRQFLAGS   .softirqs_enabled = 1,
 #else
 # define trace_hardirqs_on()           do { } while (0)
 # define trace_softirqs_enabled(p)     0
 # define trace_hardirq_enter()         do { } while (0)
 # define trace_hardirq_exit()          do { } while (0)
+# define INIT_TRACE_IRQFLAGS
+#endif
+
+#if defined(CONFIG_TRACE_IRQFLAGS) && !defined(CONFIG_PREEMPT_RT_FULL)
+# define lockdep_softirq_enter() do { current->softirq_context++; } while (0)
+# define lockdep_softirq_exit()         do { current->softirq_context--; } while (0)
+#else
 # define lockdep_softirq_enter()       do { } while (0)
 # define lockdep_softirq_exit()                do { } while (0)
-# define INIT_TRACE_IRQFLAGS
 #endif
 
 #if defined(CONFIG_IRQSOFF_TRACER) || \
 
 #define irqs_disabled_flags(flags) raw_irqs_disabled_flags(flags)
 
+/*
+ * local_irq* variants depending on RT/!RT
+ */
+#ifdef CONFIG_PREEMPT_RT_FULL
+# define local_irq_disable_nort()      do { } while (0)
+# define local_irq_enable_nort()       do { } while (0)
+# define local_irq_save_nort(flags)    local_save_flags(flags)
+# define local_irq_restore_nort(flags) (void)(flags)
+# define local_irq_disable_rt()                local_irq_disable()
+# define local_irq_enable_rt()         local_irq_enable()
+#else
+# define local_irq_disable_nort()      local_irq_disable()
+# define local_irq_enable_nort()       local_irq_enable()
+# define local_irq_save_nort(flags)    local_irq_save(flags)
+# define local_irq_restore_nort(flags) local_irq_restore(flags)
+# define local_irq_disable_rt()                do { } while (0)
+# define local_irq_enable_rt()         do { } while (0)
+#endif
+
 #endif
index 344eb87..757524c 100644 (file)
@@ -347,32 +347,56 @@ static inline struct journal_head *bh2jh(struct buffer_head *bh)
 
 static inline void jbd_lock_bh_state(struct buffer_head *bh)
 {
+#ifndef CONFIG_PREEMPT_RT_BASE
        bit_spin_lock(BH_State, &bh->b_state);
+#else
+       spin_lock(&bh->b_state_lock);
+#endif
 }
 
 static inline int jbd_trylock_bh_state(struct buffer_head *bh)
 {
+#ifndef CONFIG_PREEMPT_RT_BASE
        return bit_spin_trylock(BH_State, &bh->b_state);
+#else
+       return spin_trylock(&bh->b_state_lock);
+#endif
 }
 
 static inline int jbd_is_locked_bh_state(struct buffer_head *bh)
 {
+#ifndef CONFIG_PREEMPT_RT_BASE
        return bit_spin_is_locked(BH_State, &bh->b_state);
+#else
+       return spin_is_locked(&bh->b_state_lock);
+#endif
 }
 
 static inline void jbd_unlock_bh_state(struct buffer_head *bh)
 {
+#ifndef CONFIG_PREEMPT_RT_BASE
        bit_spin_unlock(BH_State, &bh->b_state);
+#else
+       spin_unlock(&bh->b_state_lock);
+#endif
 }
 
 static inline void jbd_lock_bh_journal_head(struct buffer_head *bh)
 {
+#ifndef CONFIG_PREEMPT_RT_BASE
        bit_spin_lock(BH_JournalHead, &bh->b_state);
+#else
+       spin_lock(&bh->b_journal_head_lock);
+#endif
 }
 
 static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh)
 {
+#ifndef CONFIG_PREEMPT_RT_BASE
        bit_spin_unlock(BH_JournalHead, &bh->b_state);
+#else
+       spin_unlock(&bh->b_journal_head_lock);
+#endif
 }
 
 #define J_ASSERT(assert)       BUG_ON(!(assert))
index 410deca..0861beb 100644 (file)
@@ -167,6 +167,7 @@ extern __printf(2, 0) int vkdb_printf(enum kdb_msgsrc src, const char *fmt,
 extern __printf(1, 2) int kdb_printf(const char *, ...);
 typedef __printf(1, 2) int (*kdb_printf_t)(const char *, ...);
 
+#define in_kdb_printk()        (kdb_trap_printk)
 extern void kdb_init(int level);
 
 /* Access to kdb specific polling devices */
@@ -201,6 +202,7 @@ extern int kdb_register_flags(char *, kdb_func_t, char *, char *,
 extern int kdb_unregister(char *);
 #else /* ! CONFIG_KGDB_KDB */
 static inline __printf(1, 2) int kdb_printf(const char *fmt, ...) { return 0; }
+#define in_kdb_printk() (0)
 static inline void kdb_init(int level) {}
 static inline int kdb_register(char *cmd, kdb_func_t func, char *usage,
                               char *help, short minlen) { return 0; }
index d83fc66..1699cbd 100644 (file)
@@ -195,6 +195,9 @@ extern int _cond_resched(void);
  */
 # define might_sleep() \
        do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
+
+# define might_sleep_no_state_check() \
+       do { ___might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
 # define sched_annotate_sleep()        (current->task_state_change = 0)
 #else
   static inline void ___might_sleep(const char *file, int line,
@@ -202,6 +205,7 @@ extern int _cond_resched(void);
   static inline void __might_sleep(const char *file, int line,
                                   int preempt_offset) { }
 # define might_sleep() do { might_resched(); } while (0)
+# define might_sleep_no_state_check() do { might_resched(); } while (0)
 # define sched_annotate_sleep() do { } while (0)
 #endif
 
@@ -489,6 +493,7 @@ extern enum system_states {
        SYSTEM_HALT,
        SYSTEM_POWER_OFF,
        SYSTEM_RESTART,
+       SYSTEM_SUSPEND,
 } system_state;
 
 #define TAINT_PROPRIETARY_MODULE       0
index cb48330..4e50623 100644 (file)
@@ -2,6 +2,7 @@
 #define _LINUX_LIST_BL_H
 
 #include <linux/list.h>
+#include <linux/spinlock.h>
 #include <linux/bit_spinlock.h>
 
 /*
 
 struct hlist_bl_head {
        struct hlist_bl_node *first;
+#ifdef CONFIG_PREEMPT_RT_BASE
+       raw_spinlock_t lock;
+#endif
 };
 
 struct hlist_bl_node {
        struct hlist_bl_node *next, **pprev;
 };
-#define INIT_HLIST_BL_HEAD(ptr) \
-       ((ptr)->first = NULL)
+
+#ifdef CONFIG_PREEMPT_RT_BASE
+#define INIT_HLIST_BL_HEAD(h)          \
+do {                                   \
+       (h)->first = NULL;              \
+       raw_spin_lock_init(&(h)->lock); \
+} while (0)
+#else
+#define INIT_HLIST_BL_HEAD(h) (h)->first = NULL
+#endif
 
 static inline void INIT_HLIST_BL_NODE(struct hlist_bl_node *h)
 {
@@ -118,12 +130,26 @@ static inline void hlist_bl_del_init(struct hlist_bl_node *n)
 
 static inline void hlist_bl_lock(struct hlist_bl_head *b)
 {
+#ifndef CONFIG_PREEMPT_RT_BASE
        bit_spin_lock(0, (unsigned long *)b);
+#else
+       raw_spin_lock(&b->lock);
+#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
+       __set_bit(0, (unsigned long *)b);
+#endif
+#endif
 }
 
 static inline void hlist_bl_unlock(struct hlist_bl_head *b)
 {
+#ifndef CONFIG_PREEMPT_RT_BASE
        __bit_spin_unlock(0, (unsigned long *)b);
+#else
+#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
+       __clear_bit(0, (unsigned long *)b);
+#endif
+       raw_spin_unlock(&b->lock);
+#endif
 }
 
 static inline bool hlist_bl_is_locked(struct hlist_bl_head *b)
diff --git a/include/linux/locallock.h b/include/linux/locallock.h
new file mode 100644 (file)
index 0000000..0c3ff5b
--- /dev/null
@@ -0,0 +1,297 @@
+#ifndef _LINUX_LOCALLOCK_H
+#define _LINUX_LOCALLOCK_H
+
+#include <linux/percpu.h>
+#include <linux/spinlock.h>
+
+#ifdef CONFIG_PREEMPT_RT_BASE
+
+#ifdef CONFIG_DEBUG_SPINLOCK
+# define LL_WARN(cond) WARN_ON(cond)
+#else
+# define LL_WARN(cond) do { } while (0)
+#endif
+
+/*
+ * per cpu lock based substitute for local_irq_*()
+ */
+struct local_irq_lock {
+       spinlock_t              lock;
+       struct task_struct      *owner;
+       int                     nestcnt;
+       unsigned long           flags;
+};
+
+#define DEFINE_LOCAL_IRQ_LOCK(lvar)                                    \
+       DEFINE_PER_CPU(struct local_irq_lock, lvar) = {                 \
+               .lock = __SPIN_LOCK_UNLOCKED((lvar).lock) }
+
+#define DECLARE_LOCAL_IRQ_LOCK(lvar)                                   \
+       DECLARE_PER_CPU(struct local_irq_lock, lvar)
+
+#define local_irq_lock_init(lvar)                                      \
+       do {                                                            \
+               int __cpu;                                              \
+               for_each_possible_cpu(__cpu)                            \
+                       spin_lock_init(&per_cpu(lvar, __cpu).lock);     \
+       } while (0)
+
+/*
+ * spin_lock|trylock|unlock_local flavour that does not migrate disable
+ * used for __local_lock|trylock|unlock where get_local_var/put_local_var
+ * already takes care of the migrate_disable/enable
+ * for CONFIG_PREEMPT_BASE map to the normal spin_* calls.
+ */
+#ifdef CONFIG_PREEMPT_RT_FULL
+# define spin_lock_local(lock)                 rt_spin_lock__no_mg(lock)
+# define spin_trylock_local(lock)              rt_spin_trylock__no_mg(lock)
+# define spin_unlock_local(lock)               rt_spin_unlock__no_mg(lock)
+#else
+# define spin_lock_local(lock)                 spin_lock(lock)
+# define spin_trylock_local(lock)              spin_trylock(lock)
+# define spin_unlock_local(lock)               spin_unlock(lock)
+#endif
+
+static inline void __local_lock(struct local_irq_lock *lv)
+{
+       if (lv->owner != current) {
+               spin_lock_local(&lv->lock);
+               LL_WARN(lv->owner);
+               LL_WARN(lv->nestcnt);
+               lv->owner = current;
+       }
+       lv->nestcnt++;
+}
+
+#define local_lock(lvar)                                       \
+       do { __local_lock(&get_local_var(lvar)); } while (0)
+
+#define local_lock_on(lvar, cpu)                               \
+       do { __local_lock(&per_cpu(lvar, cpu)); } while (0)
+
+static inline int __local_trylock(struct local_irq_lock *lv)
+{
+       if (lv->owner != current && spin_trylock_local(&lv->lock)) {
+               LL_WARN(lv->owner);
+               LL_WARN(lv->nestcnt);
+               lv->owner = current;
+               lv->nestcnt = 1;
+               return 1;
+       } else if (lv->owner == current) {
+               lv->nestcnt++;
+               return 1;
+       }
+       return 0;
+}
+
+#define local_trylock(lvar)                                            \
+       ({                                                              \
+               int __locked;                                           \
+               __locked = __local_trylock(&get_local_var(lvar));       \
+               if (!__locked)                                          \
+                       put_local_var(lvar);                            \
+               __locked;                                               \
+       })
+
+static inline void __local_unlock(struct local_irq_lock *lv)
+{
+       LL_WARN(lv->nestcnt == 0);
+       LL_WARN(lv->owner != current);
+       if (--lv->nestcnt)
+               return;
+
+       lv->owner = NULL;
+       spin_unlock_local(&lv->lock);
+}
+
+#define local_unlock(lvar)                                     \
+       do {                                                    \
+               __local_unlock(this_cpu_ptr(&lvar));            \
+               put_local_var(lvar);                            \
+       } while (0)
+
+#define local_unlock_on(lvar, cpu)                       \
+       do { __local_unlock(&per_cpu(lvar, cpu)); } while (0)
+
+static inline void __local_lock_irq(struct local_irq_lock *lv)
+{
+       spin_lock_irqsave(&lv->lock, lv->flags);
+       LL_WARN(lv->owner);
+       LL_WARN(lv->nestcnt);
+       lv->owner = current;
+       lv->nestcnt = 1;
+}
+
+#define local_lock_irq(lvar)                                           \
+       do { __local_lock_irq(&get_local_var(lvar)); } while (0)
+
+#define local_lock_irq_on(lvar, cpu)                                   \
+       do { __local_lock_irq(&per_cpu(lvar, cpu)); } while (0)
+
+static inline void __local_unlock_irq(struct local_irq_lock *lv)
+{
+       LL_WARN(!lv->nestcnt);
+       LL_WARN(lv->owner != current);
+       lv->owner = NULL;
+       lv->nestcnt = 0;
+       spin_unlock_irq(&lv->lock);
+}
+
+#define local_unlock_irq(lvar)                                         \
+       do {                                                            \
+               __local_unlock_irq(this_cpu_ptr(&lvar));                \
+               put_local_var(lvar);                                    \
+       } while (0)
+
+#define local_unlock_irq_on(lvar, cpu)                                 \
+       do {                                                            \
+               __local_unlock_irq(&per_cpu(lvar, cpu));                \
+       } while (0)
+
+static inline int __local_lock_irqsave(struct local_irq_lock *lv)
+{
+       if (lv->owner != current) {
+               __local_lock_irq(lv);
+               return 0;
+       } else {
+               lv->nestcnt++;
+               return 1;
+       }
+}
+
+#define local_lock_irqsave(lvar, _flags)                               \
+       do {                                                            \
+               if (__local_lock_irqsave(&get_local_var(lvar)))         \
+                       put_local_var(lvar);                            \
+               _flags = __this_cpu_read(lvar.flags);                   \
+       } while (0)
+
+#define local_lock_irqsave_on(lvar, _flags, cpu)                       \
+       do {                                                            \
+               __local_lock_irqsave(&per_cpu(lvar, cpu));              \
+               _flags = per_cpu(lvar, cpu).flags;                      \
+       } while (0)
+
+static inline int __local_unlock_irqrestore(struct local_irq_lock *lv,
+                                           unsigned long flags)
+{
+       LL_WARN(!lv->nestcnt);
+       LL_WARN(lv->owner != current);
+       if (--lv->nestcnt)
+               return 0;
+
+       lv->owner = NULL;
+       spin_unlock_irqrestore(&lv->lock, lv->flags);
+       return 1;
+}
+
+#define local_unlock_irqrestore(lvar, flags)                           \
+       do {                                                            \
+               if (__local_unlock_irqrestore(this_cpu_ptr(&lvar), flags)) \
+                       put_local_var(lvar);                            \
+       } while (0)
+
+#define local_unlock_irqrestore_on(lvar, flags, cpu)                   \
+       do {                                                            \
+               __local_unlock_irqrestore(&per_cpu(lvar, cpu), flags);  \
+       } while (0)
+
+#define local_spin_trylock_irq(lvar, lock)                             \
+       ({                                                              \
+               int __locked;                                           \
+               local_lock_irq(lvar);                                   \
+               __locked = spin_trylock(lock);                          \
+               if (!__locked)                                          \
+                       local_unlock_irq(lvar);                         \
+               __locked;                                               \
+       })
+
+#define local_spin_lock_irq(lvar, lock)                                        \
+       do {                                                            \
+               local_lock_irq(lvar);                                   \
+               spin_lock(lock);                                        \
+       } while (0)
+
+#define local_spin_unlock_irq(lvar, lock)                              \
+       do {                                                            \
+               spin_unlock(lock);                                      \
+               local_unlock_irq(lvar);                                 \
+       } while (0)
+
+#define local_spin_lock_irqsave(lvar, lock, flags)                     \
+       do {                                                            \
+               local_lock_irqsave(lvar, flags);                        \
+               spin_lock(lock);                                        \
+       } while (0)
+
+#define local_spin_unlock_irqrestore(lvar, lock, flags)                        \
+       do {                                                            \
+               spin_unlock(lock);                                      \
+               local_unlock_irqrestore(lvar, flags);                   \
+       } while (0)
+
+#define get_locked_var(lvar, var)                                      \
+       (*({                                                            \
+               local_lock(lvar);                                       \
+               this_cpu_ptr(&var);                                     \
+       }))
+
+#define put_locked_var(lvar, var)      local_unlock(lvar);
+
+#define get_locked_ptr(lvar, var)                                      \
+       ({                                                              \
+               local_lock(lvar);                                       \
+               this_cpu_ptr(var);                                      \
+       })
+
+#define put_locked_ptr(lvar, var)      local_unlock(lvar);
+
+#define local_lock_cpu(lvar)                                           \
+       ({                                                              \
+               local_lock(lvar);                                       \
+               smp_processor_id();                                     \
+       })
+
+#define local_unlock_cpu(lvar)                 local_unlock(lvar)
+
+#else /* PREEMPT_RT_BASE */
+
+#define DEFINE_LOCAL_IRQ_LOCK(lvar)            __typeof__(const int) lvar
+#define DECLARE_LOCAL_IRQ_LOCK(lvar)           extern __typeof__(const int) lvar
+
+static inline void local_irq_lock_init(int lvar) { }
+
+#define local_trylock(lvar)                                    \
+       ({                                                      \
+               preempt_disable();                              \
+               1;                                              \
+       })
+
+#define local_lock(lvar)                       preempt_disable()
+#define local_unlock(lvar)                     preempt_enable()
+#define local_lock_irq(lvar)                   local_irq_disable()
+#define local_lock_irq_on(lvar, cpu)           local_irq_disable()
+#define local_unlock_irq(lvar)                 local_irq_enable()
+#define local_unlock_irq_on(lvar, cpu)         local_irq_enable()
+#define local_lock_irqsave(lvar, flags)                local_irq_save(flags)
+#define local_unlock_irqrestore(lvar, flags)   local_irq_restore(flags)
+
+#define local_spin_trylock_irq(lvar, lock)     spin_trylock_irq(lock)
+#define local_spin_lock_irq(lvar, lock)                spin_lock_irq(lock)
+#define local_spin_unlock_irq(lvar, lock)      spin_unlock_irq(lock)
+#define local_spin_lock_irqsave(lvar, lock, flags)     \
+       spin_lock_irqsave(lock, flags)
+#define local_spin_unlock_irqrestore(lvar, lock, flags)        \
+       spin_unlock_irqrestore(lock, flags)
+
+#define get_locked_var(lvar, var)              get_cpu_var(var)
+#define put_locked_var(lvar, var)              put_cpu_var(var)
+#define get_locked_ptr(lvar, var)              get_cpu_ptr(var)
+#define put_locked_ptr(lvar, var)              put_cpu_ptr(var)
+
+#define local_lock_cpu(lvar)                   get_cpu()
+#define local_unlock_cpu(lvar)                 put_cpu()
+
+#endif
+
+#endif
index 95512ce..a9bd5c7 100644 (file)
@@ -11,6 +11,7 @@
 #include <linux/completion.h>
 #include <linux/cpumask.h>
 #include <linux/uprobes.h>
+#include <linux/rcupdate.h>
 #include <linux/page-flags-layout.h>
 #include <linux/workqueue.h>
 #include <asm/page.h>
@@ -535,6 +536,9 @@ struct mm_struct {
        bool tlb_flush_batched;
 #endif
        struct uprobes_state uprobes_state;
+#ifdef CONFIG_PREEMPT_RT_BASE
+       struct rcu_head delayed_drop;
+#endif
 #ifdef CONFIG_X86_INTEL_MPX
        /* address of the bounds directory */
        void __user *bd_addr;
index 49f0aae..fb10e0a 100644 (file)
@@ -501,6 +501,7 @@ static inline int module_is_live(struct module *mod)
 struct module *__module_text_address(unsigned long addr);
 struct module *__module_address(unsigned long addr);
 bool is_module_address(unsigned long addr);
+bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr);
 bool is_module_percpu_address(unsigned long addr);
 bool is_module_text_address(unsigned long addr);
 
@@ -668,6 +669,11 @@ static inline bool is_module_percpu_address(unsigned long addr)
        return false;
 }
 
+static inline bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
+{
+       return false;
+}
+
 static inline bool is_module_text_address(unsigned long addr)
 {
        return false;
index 2cb7531..b3fdfc8 100644 (file)
 #include <asm/processor.h>
 #include <linux/osq_lock.h>
 
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define __DEP_MAP_MUTEX_INITIALIZER(lockname) \
+       , .dep_map = { .name = #lockname }
+#else
+# define __DEP_MAP_MUTEX_INITIALIZER(lockname)
+#endif
+
+#ifdef CONFIG_PREEMPT_RT_FULL
+# include <linux/mutex_rt.h>
+#else
+
 /*
  * Simple, straightforward mutexes with strict semantics:
  *
@@ -99,13 +110,6 @@ do {                                                        \
 static inline void mutex_destroy(struct mutex *lock) {}
 #endif
 
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# define __DEP_MAP_MUTEX_INITIALIZER(lockname) \
-               , .dep_map = { .name = #lockname }
-#else
-# define __DEP_MAP_MUTEX_INITIALIZER(lockname)
-#endif
-
 #define __MUTEX_INITIALIZER(lockname) \
                { .count = ATOMIC_INIT(1) \
                , .wait_lock = __SPIN_LOCK_UNLOCKED(lockname.wait_lock) \
@@ -173,6 +177,8 @@ extern int __must_check mutex_lock_killable(struct mutex *lock);
 extern int mutex_trylock(struct mutex *lock);
 extern void mutex_unlock(struct mutex *lock);
 
+#endif /* !PREEMPT_RT_FULL */
+
 extern int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock);
 
 #endif /* __LINUX_MUTEX_H */
diff --git a/include/linux/mutex_rt.h b/include/linux/mutex_rt.h
new file mode 100644 (file)
index 0000000..e0284ed
--- /dev/null
@@ -0,0 +1,89 @@
+#ifndef __LINUX_MUTEX_RT_H
+#define __LINUX_MUTEX_RT_H
+
+#ifndef __LINUX_MUTEX_H
+#error "Please include mutex.h"
+#endif
+
+#include <linux/rtmutex.h>
+
+/* FIXME: Just for __lockfunc */
+#include <linux/spinlock.h>
+
+struct mutex {
+       struct rt_mutex         lock;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+       struct lockdep_map      dep_map;
+#endif
+};
+
+#define __MUTEX_INITIALIZER(mutexname)                                 \
+       {                                                               \
+               .lock = __RT_MUTEX_INITIALIZER(mutexname.lock)          \
+               __DEP_MAP_MUTEX_INITIALIZER(mutexname)                  \
+       }
+
+#define DEFINE_MUTEX(mutexname)                                                \
+       struct mutex mutexname = __MUTEX_INITIALIZER(mutexname)
+
+extern void __mutex_do_init(struct mutex *lock, const char *name, struct lock_class_key *key);
+extern void __lockfunc _mutex_lock(struct mutex *lock);
+extern int __lockfunc _mutex_lock_interruptible(struct mutex *lock);
+extern int __lockfunc _mutex_lock_killable(struct mutex *lock);
+extern void __lockfunc _mutex_lock_nested(struct mutex *lock, int subclass);
+extern void __lockfunc _mutex_lock_nest_lock(struct mutex *lock, struct lockdep_map *nest_lock);
+extern int __lockfunc _mutex_lock_interruptible_nested(struct mutex *lock, int subclass);
+extern int __lockfunc _mutex_lock_killable_nested(struct mutex *lock, int subclass);
+extern int __lockfunc _mutex_trylock(struct mutex *lock);
+extern void __lockfunc _mutex_unlock(struct mutex *lock);
+
+#define mutex_is_locked(l)             rt_mutex_is_locked(&(l)->lock)
+#define mutex_lock(l)                  _mutex_lock(l)
+#define mutex_lock_interruptible(l)    _mutex_lock_interruptible(l)
+#define mutex_lock_killable(l)         _mutex_lock_killable(l)
+#define mutex_trylock(l)               _mutex_trylock(l)
+#define mutex_unlock(l)                        _mutex_unlock(l)
+
+#ifdef CONFIG_DEBUG_MUTEXES
+#define mutex_destroy(l)               rt_mutex_destroy(&(l)->lock)
+#else
+static inline void mutex_destroy(struct mutex *lock) {}
+#endif
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define mutex_lock_nested(l, s)       _mutex_lock_nested(l, s)
+# define mutex_lock_interruptible_nested(l, s) \
+                                       _mutex_lock_interruptible_nested(l, s)
+# define mutex_lock_killable_nested(l, s) \
+                                       _mutex_lock_killable_nested(l, s)
+
+# define mutex_lock_nest_lock(lock, nest_lock)                         \
+do {                                                                   \
+       typecheck(struct lockdep_map *, &(nest_lock)->dep_map);         \
+       _mutex_lock_nest_lock(lock, &(nest_lock)->dep_map);             \
+} while (0)
+
+#else
+# define mutex_lock_nested(l, s)       _mutex_lock(l)
+# define mutex_lock_interruptible_nested(l, s) \
+                                       _mutex_lock_interruptible(l)
+# define mutex_lock_killable_nested(l, s) \
+                                       _mutex_lock_killable(l)
+# define mutex_lock_nest_lock(lock, nest_lock) mutex_lock(lock)
+#endif
+
+# define mutex_init(mutex)                             \
+do {                                                   \
+       static struct lock_class_key __key;             \
+                                                       \
+       rt_mutex_init(&(mutex)->lock);                  \
+       __mutex_do_init((mutex), #mutex, &__key);       \
+} while (0)
+
+# define __mutex_init(mutex, name, key)                        \
+do {                                                   \
+       rt_mutex_init(&(mutex)->lock);                  \
+       __mutex_do_init((mutex), name, key);            \
+} while (0)
+
+#endif
index 4d1b105..5decbf0 100644 (file)
@@ -396,7 +396,19 @@ typedef enum rx_handler_result rx_handler_result_t;
 typedef rx_handler_result_t rx_handler_func_t(struct sk_buff **pskb);
 
 void __napi_schedule(struct napi_struct *n);
+
+/*
+ * When PREEMPT_RT_FULL is defined, all device interrupt handlers
+ * run as threads, and they can also be preempted (without PREEMPT_RT
+ * interrupt threads can not be preempted). Which means that calling
+ * __napi_schedule_irqoff() from an interrupt handler can be preempted
+ * and can corrupt the napi->poll_list.
+ */
+#ifdef CONFIG_PREEMPT_RT_FULL
+#define __napi_schedule_irqoff(n) __napi_schedule(n)
+#else
 void __napi_schedule_irqoff(struct napi_struct *n);
+#endif
 
 static inline bool napi_disable_pending(struct napi_struct *n)
 {
@@ -582,7 +594,11 @@ struct netdev_queue {
  * write-mostly part
  */
        spinlock_t              _xmit_lock ____cacheline_aligned_in_smp;
+#ifdef CONFIG_PREEMPT_RT_FULL
+       struct task_struct      *xmit_lock_owner;
+#else
        int                     xmit_lock_owner;
+#endif
        /*
         * Time (in jiffies) of last Tx
         */
@@ -2479,14 +2495,53 @@ void netdev_freemem(struct net_device *dev);
 void synchronize_net(void);
 int init_dummy_netdev(struct net_device *dev);
 
+#define XMIT_RECURSION_LIMIT   10
+#ifdef CONFIG_PREEMPT_RT_FULL
+static inline int dev_recursion_level(void)
+{
+       return current->xmit_recursion;
+}
+
+static inline int xmit_rec_read(void)
+{
+       return current->xmit_recursion;
+}
+
+static inline void xmit_rec_inc(void)
+{
+       current->xmit_recursion++;
+}
+
+static inline void xmit_rec_dec(void)
+{
+       current->xmit_recursion--;
+}
+
+#else
+
 DECLARE_PER_CPU(int, xmit_recursion);
-#define XMIT_RECURSION_LIMIT   8
 
 static inline int dev_recursion_level(void)
 {
        return this_cpu_read(xmit_recursion);
 }
 
+static inline int xmit_rec_read(void)
+{
+       return __this_cpu_read(xmit_recursion);
+}
+
+static inline void xmit_rec_inc(void)
+{
+       __this_cpu_inc(xmit_recursion);
+}
+
+static inline void xmit_rec_dec(void)
+{
+       __this_cpu_dec(xmit_recursion);
+}
+#endif
+
 struct net_device *dev_get_by_index(struct net *net, int ifindex);
 struct net_device *__dev_get_by_index(struct net *net, int ifindex);
 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex);
@@ -2871,6 +2926,7 @@ struct softnet_data {
        unsigned int            dropped;
        struct sk_buff_head     input_pkt_queue;
        struct napi_struct      backlog;
+       struct sk_buff_head     tofree_queue;
 
 };
 
@@ -3573,41 +3629,79 @@ static inline u32 netif_msg_init(int debug_value, int default_msg_enable_bits)
        return (1U << debug_value) - 1;
 }
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+static inline void netdev_queue_set_owner(struct netdev_queue *txq, int cpu)
+{
+       txq->xmit_lock_owner = current;
+}
+
+static inline void netdev_queue_clear_owner(struct netdev_queue *txq)
+{
+       txq->xmit_lock_owner = NULL;
+}
+
+static inline bool netdev_queue_has_owner(struct netdev_queue *txq)
+{
+       if (txq->xmit_lock_owner != NULL)
+               return true;
+       return false;
+}
+
+#else
+
+static inline void netdev_queue_set_owner(struct netdev_queue *txq, int cpu)
+{
+       txq->xmit_lock_owner = cpu;
+}
+
+static inline void netdev_queue_clear_owner(struct netdev_queue *txq)
+{
+       txq->xmit_lock_owner = -1;
+}
+
+static inline bool netdev_queue_has_owner(struct netdev_queue *txq)
+{
+       if (txq->xmit_lock_owner != -1)
+               return true;
+       return false;
+}
+#endif
+
 static inline void __netif_tx_lock(struct netdev_queue *txq, int cpu)
 {
        spin_lock(&txq->_xmit_lock);
-       txq->xmit_lock_owner = cpu;
+       netdev_queue_set_owner(txq, cpu);
 }
 
 static inline void __netif_tx_lock_bh(struct netdev_queue *txq)
 {
        spin_lock_bh(&txq->_xmit_lock);
-       txq->xmit_lock_owner = smp_processor_id();
+       netdev_queue_set_owner(txq, smp_processor_id());
 }
 
 static inline bool __netif_tx_trylock(struct netdev_queue *txq)
 {
        bool ok = spin_trylock(&txq->_xmit_lock);
        if (likely(ok))
-               txq->xmit_lock_owner = smp_processor_id();
+               netdev_queue_set_owner(txq, smp_processor_id());
        return ok;
 }
 
 static inline void __netif_tx_unlock(struct netdev_queue *txq)
 {
-       txq->xmit_lock_owner = -1;
+       netdev_queue_clear_owner(txq);
        spin_unlock(&txq->_xmit_lock);
 }
 
 static inline void __netif_tx_unlock_bh(struct netdev_queue *txq)
 {
-       txq->xmit_lock_owner = -1;
+       netdev_queue_clear_owner(txq);
        spin_unlock_bh(&txq->_xmit_lock);
 }
 
 static inline void txq_trans_update(struct netdev_queue *txq)
 {
-       if (txq->xmit_lock_owner != -1)
+       if (netdev_queue_has_owner(txq))
                txq->trans_start = jiffies;
 }
 
index 69111fa..e64c02a 100644 (file)
@@ -4,6 +4,7 @@
 
 #include <linux/netdevice.h>
 #include <linux/static_key.h>
+#include <linux/locallock.h>
 #include <uapi/linux/netfilter/x_tables.h>
 
 /* Test a struct->invflags and a boolean for inequality */
@@ -302,6 +303,8 @@ void xt_free_table_info(struct xt_table_info *info);
  */
 DECLARE_PER_CPU(seqcount_t, xt_recseq);
 
+DECLARE_LOCAL_IRQ_LOCK(xt_write_lock);
+
 /* xt_tee_enabled - true if x_tables needs to handle reentrancy
  *
  * Enabled if current ip(6)tables ruleset has at least one -j TEE rule.
@@ -322,6 +325,9 @@ static inline unsigned int xt_write_recseq_begin(void)
 {
        unsigned int addend;
 
+       /* RT protection */
+       local_lock(xt_write_lock);
+
        /*
         * Low order bit of sequence is set if we already
         * called xt_write_recseq_begin().
@@ -352,6 +358,7 @@ static inline void xt_write_recseq_end(unsigned int addend)
        /* this is kind of a write_seqcount_end(), but addend is 0 or 1 */
        smp_wmb();
        __this_cpu_add(xt_recseq.sequence, addend);
+       local_unlock(xt_write_lock);
 }
 
 /*
index 810124b..d54ca43 100644 (file)
@@ -165,7 +165,11 @@ struct nfs_inode {
 
        /* Readers: in-flight sillydelete RPC calls */
        /* Writers: rmdir */
+#ifdef CONFIG_PREEMPT_RT_BASE
+       struct semaphore        rmdir_sem;
+#else
        struct rw_semaphore     rmdir_sem;
+#endif
 
 #if IS_ENABLED(CONFIG_NFS_V4)
        struct nfs4_cached_acl  *nfs4_acl;
index 3bf867a..71c6bdd 100644 (file)
@@ -1490,7 +1490,7 @@ struct nfs_unlinkdata {
        struct nfs_removeargs args;
        struct nfs_removeres res;
        struct dentry *dentry;
-       wait_queue_head_t wq;
+       struct swait_queue_head wq;
        struct rpc_cred *cred;
        struct nfs_fattr dir_attr;
        long timeout;
index 4149868..babe5b9 100644 (file)
@@ -6,7 +6,7 @@
  *
  *                             Alan Cox <Alan.Cox@linux.org>
  */
+
 #ifndef _LINUX_NOTIFIER_H
 #define _LINUX_NOTIFIER_H
 #include <linux/errno.h>
@@ -42,9 +42,7 @@
  * in srcu_notifier_call_chain(): no cache bounces and no memory barriers.
  * As compensation, srcu_notifier_chain_unregister() is rather expensive.
  * SRCU notifier chains should be used when the chain will be called very
- * often but notifier_blocks will seldom be removed.  Also, SRCU notifier
- * chains are slightly more difficult to use because they require special
- * runtime initialization.
+ * often but notifier_blocks will seldom be removed.
  */
 
 struct notifier_block;
@@ -90,7 +88,7 @@ struct srcu_notifier_head {
                (name)->head = NULL;            \
        } while (0)
 
-/* srcu_notifier_heads must be initialized and cleaned up dynamically */
+/* srcu_notifier_heads must be cleaned up dynamically */
 extern void srcu_init_notifier_head(struct srcu_notifier_head *nh);
 #define srcu_cleanup_notifier_head(name)       \
                cleanup_srcu_struct(&(name)->srcu);
@@ -103,7 +101,13 @@ extern void srcu_init_notifier_head(struct srcu_notifier_head *nh);
                .head = NULL }
 #define RAW_NOTIFIER_INIT(name)        {                               \
                .head = NULL }
-/* srcu_notifier_heads cannot be initialized statically */
+
+#define SRCU_NOTIFIER_INIT(name, pcpu)                         \
+       {                                                       \
+               .mutex = __MUTEX_INITIALIZER(name.mutex),       \
+               .head = NULL,                                   \
+               .srcu = __SRCU_STRUCT_INIT(name.srcu, pcpu),    \
+       }
 
 #define ATOMIC_NOTIFIER_HEAD(name)                             \
        struct atomic_notifier_head name =                      \
@@ -115,6 +119,18 @@ extern void srcu_init_notifier_head(struct srcu_notifier_head *nh);
        struct raw_notifier_head name =                         \
                RAW_NOTIFIER_INIT(name)
 
+#define _SRCU_NOTIFIER_HEAD(name, mod)                         \
+       static DEFINE_PER_CPU(struct srcu_struct_array,         \
+                       name##_head_srcu_array);                \
+       mod struct srcu_notifier_head name =                    \
+                       SRCU_NOTIFIER_INIT(name, name##_head_srcu_array)
+
+#define SRCU_NOTIFIER_HEAD(name)                               \
+       _SRCU_NOTIFIER_HEAD(name, )
+
+#define SRCU_NOTIFIER_HEAD_STATIC(name)                                \
+       _SRCU_NOTIFIER_HEAD(name, static)
+
 #ifdef __KERNEL__
 
 extern int atomic_notifier_chain_register(struct atomic_notifier_head *nh,
@@ -184,12 +200,12 @@ static inline int notifier_to_errno(int ret)
 
 /*
  *     Declared notifiers so far. I can imagine quite a few more chains
- *     over time (eg laptop power reset chains, reboot chain (to clean 
+ *     over time (eg laptop power reset chains, reboot chain (to clean
  *     device units up), device [un]mount chain, module load/unload chain,
- *     low memory chain, screenblank chain (for plug in modular screenblankers) 
+ *     low memory chain, screenblank chain (for plug in modular screenblankers)
  *     VC switch chains (for loadable kernel svgalib VC switch helpers) etc...
  */
+
 /* CPU notfiers are defined in include/linux/cpu.h. */
 
 /* netdevice notifiers are defined in include/linux/netdevice.h */
index 5b2e615..ea940f4 100644 (file)
@@ -4,7 +4,7 @@
 #include <linux/atomic.h>
 #include <linux/rwsem.h>
 #include <linux/percpu.h>
-#include <linux/wait.h>
+#include <linux/swait.h>
 #include <linux/rcu_sync.h>
 #include <linux/lockdep.h>
 
@@ -12,7 +12,7 @@ struct percpu_rw_semaphore {
        struct rcu_sync         rss;
        unsigned int __percpu   *read_count;
        struct rw_semaphore     rw_sem;
-       wait_queue_head_t       writer;
+       struct swait_queue_head writer;
        int                     readers_block;
 };
 
@@ -22,13 +22,13 @@ static struct percpu_rw_semaphore name = {                          \
        .rss = __RCU_SYNC_INITIALIZER(name.rss, RCU_SCHED_SYNC),        \
        .read_count = &__percpu_rwsem_rc_##name,                        \
        .rw_sem = __RWSEM_INITIALIZER(name.rw_sem),                     \
-       .writer = __WAIT_QUEUE_HEAD_INITIALIZER(name.writer),           \
+       .writer = __SWAIT_QUEUE_HEAD_INITIALIZER(name.writer),          \
 }
 
 extern int __percpu_down_read(struct percpu_rw_semaphore *, int);
 extern void __percpu_up_read(struct percpu_rw_semaphore *);
 
-static inline void percpu_down_read_preempt_disable(struct percpu_rw_semaphore *sem)
+static inline void percpu_down_read(struct percpu_rw_semaphore *sem)
 {
        might_sleep();
 
@@ -46,16 +46,10 @@ static inline void percpu_down_read_preempt_disable(struct percpu_rw_semaphore *
        __this_cpu_inc(*sem->read_count);
        if (unlikely(!rcu_sync_is_idle(&sem->rss)))
                __percpu_down_read(sem, false); /* Unconditional memory barrier */
-       barrier();
        /*
-        * The barrier() prevents the compiler from
+        * The preempt_enable() prevents the compiler from
         * bleeding the critical section out.
         */
-}
-
-static inline void percpu_down_read(struct percpu_rw_semaphore *sem)
-{
-       percpu_down_read_preempt_disable(sem);
        preempt_enable();
 }
 
@@ -82,13 +76,9 @@ static inline int percpu_down_read_trylock(struct percpu_rw_semaphore *sem)
        return ret;
 }
 
-static inline void percpu_up_read_preempt_enable(struct percpu_rw_semaphore *sem)
+static inline void percpu_up_read(struct percpu_rw_semaphore *sem)
 {
-       /*
-        * The barrier() prevents the compiler from
-        * bleeding the critical section out.
-        */
-       barrier();
+       preempt_disable();
        /*
         * Same as in percpu_down_read().
         */
@@ -101,12 +91,6 @@ static inline void percpu_up_read_preempt_enable(struct percpu_rw_semaphore *sem
        rwsem_release(&sem->rw_sem.dep_map, 1, _RET_IP_);
 }
 
-static inline void percpu_up_read(struct percpu_rw_semaphore *sem)
-{
-       preempt_disable();
-       percpu_up_read_preempt_enable(sem);
-}
-
 extern void percpu_down_write(struct percpu_rw_semaphore *);
 extern void percpu_up_write(struct percpu_rw_semaphore *);
 
index 56939d3..b988bf4 100644 (file)
 #define PERCPU_MODULE_RESERVE          0
 #endif
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+
+#define get_local_var(var) (*({        \
+       migrate_disable();      \
+       this_cpu_ptr(&var);     }))
+
+#define put_local_var(var) do {        \
+       (void)&(var);           \
+       migrate_enable();       \
+} while (0)
+
+# define get_local_ptr(var) ({ \
+       migrate_disable();      \
+       this_cpu_ptr(var);      })
+
+# define put_local_ptr(var) do {       \
+       (void)(var);                    \
+       migrate_enable();               \
+} while (0)
+
+#else
+
+#define get_local_var(var)     get_cpu_var(var)
+#define put_local_var(var)     put_cpu_var(var)
+#define get_local_ptr(var)     get_cpu_ptr(var)
+#define put_local_ptr(var)     put_cpu_ptr(var)
+
+#endif
+
 /* minimum unit size, also is the maximum supported allocation size */
 #define PCPU_MIN_UNIT_SIZE             PFN_ALIGN(32 << 10)
 
@@ -110,6 +139,7 @@ extern int __init pcpu_page_first_chunk(size_t reserved_size,
 #endif
 
 extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align);
+extern bool __is_kernel_percpu_address(unsigned long addr, unsigned long *can_addr);
 extern bool is_kernel_percpu_address(unsigned long addr);
 
 #if !defined(CONFIG_SMP) || !defined(CONFIG_HAVE_SETUP_PER_CPU_AREA)
index 97b745d..01a5460 100644 (file)
@@ -2,6 +2,7 @@
 #define _LINUX_PID_H
 
 #include <linux/rcupdate.h>
+#include <linux/atomic.h>
 
 enum pid_type
 {
index e4b8678..7bebe32 100644 (file)
@@ -92,8 +92,8 @@ struct k_itimer {
                        struct alarm alarmtimer;
                        ktime_t interval;
                } alarm;
-               struct rcu_head rcu;
        } it;
+       struct rcu_head         rcu;
 };
 
 struct k_clock {
index 7eeceac..f97c542 100644 (file)
 #define HARDIRQ_OFFSET (1UL << HARDIRQ_SHIFT)
 #define NMI_OFFSET     (1UL << NMI_SHIFT)
 
-#define SOFTIRQ_DISABLE_OFFSET (2 * SOFTIRQ_OFFSET)
+#ifndef CONFIG_PREEMPT_RT_FULL
+# define SOFTIRQ_DISABLE_OFFSET                (2 * SOFTIRQ_OFFSET)
+#else
+# define SOFTIRQ_DISABLE_OFFSET                (0)
+#endif
 
 /* We use the MSB mostly because its available */
 #define PREEMPT_NEED_RESCHED   0x80000000
 #include <asm/preempt.h>
 
 #define hardirq_count()        (preempt_count() & HARDIRQ_MASK)
-#define softirq_count()        (preempt_count() & SOFTIRQ_MASK)
 #define irq_count()    (preempt_count() & (HARDIRQ_MASK | SOFTIRQ_MASK \
                                 | NMI_MASK))
+#ifndef CONFIG_PREEMPT_RT_FULL
+# define softirq_count()       (preempt_count() & SOFTIRQ_MASK)
+# define in_serving_softirq()  (softirq_count() & SOFTIRQ_OFFSET)
+#else
+# define softirq_count()       (0UL)
+extern int in_serving_softirq(void);
+#endif
 
 /*
  * Are we doing bottom half or hardware interrupt processing?
@@ -79,7 +89,6 @@
 #define in_irq()               (hardirq_count())
 #define in_softirq()           (softirq_count())
 #define in_interrupt()         (irq_count())
-#define in_serving_softirq()   (softirq_count() & SOFTIRQ_OFFSET)
 #define in_nmi()               (preempt_count() & NMI_MASK)
 #define in_task()              (!(preempt_count() & \
                                   (NMI_MASK | HARDIRQ_MASK | SOFTIRQ_OFFSET)))
 /*
  * The preempt_count offset after spin_lock()
  */
+#if !defined(CONFIG_PREEMPT_RT_FULL)
 #define PREEMPT_LOCK_OFFSET    PREEMPT_DISABLE_OFFSET
+#else
+#define PREEMPT_LOCK_OFFSET    0
+#endif
 
 /*
  * The preempt_count offset needed for things like:
@@ -145,6 +158,20 @@ extern void preempt_count_sub(int val);
 #define preempt_count_inc() preempt_count_add(1)
 #define preempt_count_dec() preempt_count_sub(1)
 
+#ifdef CONFIG_PREEMPT_LAZY
+#define add_preempt_lazy_count(val)    do { preempt_lazy_count() += (val); } while (0)
+#define sub_preempt_lazy_count(val)    do { preempt_lazy_count() -= (val); } while (0)
+#define inc_preempt_lazy_count()       add_preempt_lazy_count(1)
+#define dec_preempt_lazy_count()       sub_preempt_lazy_count(1)
+#define preempt_lazy_count()           (current_thread_info()->preempt_lazy_count)
+#else
+#define add_preempt_lazy_count(val)    do { } while (0)
+#define sub_preempt_lazy_count(val)    do { } while (0)
+#define inc_preempt_lazy_count()       do { } while (0)
+#define dec_preempt_lazy_count()       do { } while (0)
+#define preempt_lazy_count()           (0)
+#endif
+
 #ifdef CONFIG_PREEMPT_COUNT
 
 #define preempt_disable() \
@@ -153,13 +180,25 @@ do { \
        barrier(); \
 } while (0)
 
+#define preempt_lazy_disable() \
+do { \
+       inc_preempt_lazy_count(); \
+       barrier(); \
+} while (0)
+
 #define sched_preempt_enable_no_resched() \
 do { \
        barrier(); \
        preempt_count_dec(); \
 } while (0)
 
-#define preempt_enable_no_resched() sched_preempt_enable_no_resched()
+#ifdef CONFIG_PREEMPT_RT_BASE
+# define preempt_enable_no_resched() sched_preempt_enable_no_resched()
+# define preempt_check_resched_rt() preempt_check_resched()
+#else
+# define preempt_enable_no_resched() preempt_enable()
+# define preempt_check_resched_rt() barrier();
+#endif
 
 #define preemptible()  (preempt_count() == 0 && !irqs_disabled())
 
@@ -184,6 +223,13 @@ do { \
                __preempt_schedule(); \
 } while (0)
 
+#define preempt_lazy_enable() \
+do { \
+       dec_preempt_lazy_count(); \
+       barrier(); \
+       preempt_check_resched(); \
+} while (0)
+
 #else /* !CONFIG_PREEMPT */
 #define preempt_enable() \
 do { \
@@ -229,6 +275,7 @@ do { \
 #define preempt_disable_notrace()              barrier()
 #define preempt_enable_no_resched_notrace()    barrier()
 #define preempt_enable_notrace()               barrier()
+#define preempt_check_resched_rt()             barrier()
 #define preemptible()                          0
 
 #endif /* CONFIG_PREEMPT_COUNT */
@@ -249,10 +296,31 @@ do { \
 } while (0)
 #define preempt_fold_need_resched() \
 do { \
-       if (tif_need_resched()) \
+       if (tif_need_resched_now()) \
                set_preempt_need_resched(); \
 } while (0)
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+# define preempt_disable_rt()          preempt_disable()
+# define preempt_enable_rt()           preempt_enable()
+# define preempt_disable_nort()                barrier()
+# define preempt_enable_nort()         barrier()
+# ifdef CONFIG_SMP
+   extern void migrate_disable(void);
+   extern void migrate_enable(void);
+# else /* CONFIG_SMP */
+#  define migrate_disable()            barrier()
+#  define migrate_enable()             barrier()
+# endif /* CONFIG_SMP */
+#else
+# define preempt_disable_rt()          barrier()
+# define preempt_enable_rt()           barrier()
+# define preempt_disable_nort()                preempt_disable()
+# define preempt_enable_nort()         preempt_enable()
+# define migrate_disable()             preempt_disable()
+# define migrate_enable()              preempt_enable()
+#endif
+
 #ifdef CONFIG_PREEMPT_NOTIFIERS
 
 struct preempt_notifier;
index eac1af8..37e647a 100644 (file)
@@ -126,9 +126,11 @@ struct va_format {
 #ifdef CONFIG_EARLY_PRINTK
 extern asmlinkage __printf(1, 2)
 void early_printk(const char *fmt, ...);
+extern void printk_kill(void);
 #else
 static inline __printf(1, 2) __cold
 void early_printk(const char *s, ...) { }
+static inline void printk_kill(void) { }
 #endif
 
 #ifdef CONFIG_PRINTK_NMI
index af3581b..2772950 100644 (file)
@@ -292,6 +292,8 @@ unsigned int radix_tree_gang_lookup_slot(struct radix_tree_root *root,
 int radix_tree_preload(gfp_t gfp_mask);
 int radix_tree_maybe_preload(gfp_t gfp_mask);
 int radix_tree_maybe_preload_order(gfp_t gfp_mask, int order);
+void radix_tree_preload_end(void);
+
 void radix_tree_init(void);
 void *radix_tree_tag_set(struct radix_tree_root *root,
                        unsigned long index, unsigned int tag);
@@ -314,11 +316,6 @@ unsigned long radix_tree_range_tag_if_tagged(struct radix_tree_root *root,
 int radix_tree_tagged(struct radix_tree_root *root, unsigned int tag);
 unsigned long radix_tree_locate_item(struct radix_tree_root *root, void *item);
 
-static inline void radix_tree_preload_end(void)
-{
-       preempt_enable();
-}
-
 /**
  * struct radix_tree_iter - radix tree iterator state
  *
index 15cd754..a50fcce 100644 (file)
@@ -31,7 +31,7 @@ static inline void add_latent_entropy(void) {}
 
 extern void add_input_randomness(unsigned int type, unsigned int code,
                                 unsigned int value) __latent_entropy;
-extern void add_interrupt_randomness(int irq, int irq_flags) __latent_entropy;
+extern void add_interrupt_randomness(int irq, int irq_flags, __u64 ip) __latent_entropy;
 
 extern void get_random_bytes(void *buf, int nbytes);
 extern int add_random_ready_callback(struct random_ready_callback *rdy);
index e585018..25c6447 100644 (file)
@@ -31,7 +31,7 @@
 
 #include <linux/kernel.h>
 #include <linux/stddef.h>
-#include <linux/rcupdate.h>
+#include <linux/rcu_assign_pointer.h>
 
 struct rb_node {
        unsigned long  __rb_parent_color;
index d076183..36bfb4d 100644 (file)
@@ -26,6 +26,7 @@
 
 #include <linux/compiler.h>
 #include <linux/rbtree.h>
+#include <linux/rcupdate.h>
 
 /*
  * Please note - only struct rb_augment_callbacks and the prototypes for
diff --git a/include/linux/rcu_assign_pointer.h b/include/linux/rcu_assign_pointer.h
new file mode 100644 (file)
index 0000000..7066962
--- /dev/null
@@ -0,0 +1,54 @@
+#ifndef __LINUX_RCU_ASSIGN_POINTER_H__
+#define __LINUX_RCU_ASSIGN_POINTER_H__
+#include <linux/compiler.h>
+#include <asm/barrier.h>
+
+/**
+ * RCU_INITIALIZER() - statically initialize an RCU-protected global variable
+ * @v: The value to statically initialize with.
+ */
+#define RCU_INITIALIZER(v) (typeof(*(v)) __force __rcu *)(v)
+
+/**
+ * rcu_assign_pointer() - assign to RCU-protected pointer
+ * @p: pointer to assign to
+ * @v: value to assign (publish)
+ *
+ * Assigns the specified value to the specified RCU-protected
+ * pointer, ensuring that any concurrent RCU readers will see
+ * any prior initialization.
+ *
+ * Inserts memory barriers on architectures that require them
+ * (which is most of them), and also prevents the compiler from
+ * reordering the code that initializes the structure after the pointer
+ * assignment.  More importantly, this call documents which pointers
+ * will be dereferenced by RCU read-side code.
+ *
+ * In some special cases, you may use RCU_INIT_POINTER() instead
+ * of rcu_assign_pointer().  RCU_INIT_POINTER() is a bit faster due
+ * to the fact that it does not constrain either the CPU or the compiler.
+ * That said, using RCU_INIT_POINTER() when you should have used
+ * rcu_assign_pointer() is a very bad thing that results in
+ * impossible-to-diagnose memory corruption.  So please be careful.
+ * See the RCU_INIT_POINTER() comment header for details.
+ *
+ * Note that rcu_assign_pointer() evaluates each of its arguments only
+ * once, appearances notwithstanding.  One of the "extra" evaluations
+ * is in typeof() and the other visible only to sparse (__CHECKER__),
+ * neither of which actually execute the argument.  As with most cpp
+ * macros, this execute-arguments-only-once property is important, so
+ * please be careful when making changes to rcu_assign_pointer() and the
+ * other macros that it invokes.
+ */
+#define rcu_assign_pointer(p, v)                                             \
+({                                                                           \
+       uintptr_t _r_a_p__v = (uintptr_t)(v);                                 \
+                                                                             \
+       if (__builtin_constant_p(v) && (_r_a_p__v) == (uintptr_t)NULL)        \
+               WRITE_ONCE((p), (typeof(p))(_r_a_p__v));                      \
+       else                                                                  \
+               smp_store_release(&p, RCU_INITIALIZER((typeof(p))_r_a_p__v)); \
+       _r_a_p__v;                                                            \
+})
+
+#endif
index 96037ba..790740d 100644 (file)
@@ -46,6 +46,7 @@
 #include <linux/compiler.h>
 #include <linux/ktime.h>
 #include <linux/irqflags.h>
+#include <linux/rcu_assign_pointer.h>
 
 #include <asm/barrier.h>
 
@@ -178,6 +179,9 @@ void call_rcu(struct rcu_head *head,
 
 #endif /* #else #ifdef CONFIG_PREEMPT_RCU */
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+#define call_rcu_bh    call_rcu
+#else
 /**
  * call_rcu_bh() - Queue an RCU for invocation after a quicker grace period.
  * @head: structure to be used for queueing the RCU updates.
@@ -201,6 +205,7 @@ void call_rcu(struct rcu_head *head,
  */
 void call_rcu_bh(struct rcu_head *head,
                 rcu_callback_t func);
+#endif
 
 /**
  * call_rcu_sched() - Queue an RCU for invocation after sched grace period.
@@ -301,6 +306,11 @@ void synchronize_rcu(void);
  * types of kernel builds, the rcu_read_lock() nesting depth is unknowable.
  */
 #define rcu_preempt_depth() (current->rcu_read_lock_nesting)
+#ifndef CONFIG_PREEMPT_RT_FULL
+#define sched_rcu_preempt_depth()      rcu_preempt_depth()
+#else
+static inline int sched_rcu_preempt_depth(void) { return 0; }
+#endif
 
 #else /* #ifdef CONFIG_PREEMPT_RCU */
 
@@ -324,6 +334,8 @@ static inline int rcu_preempt_depth(void)
        return 0;
 }
 
+#define sched_rcu_preempt_depth()      rcu_preempt_depth()
+
 #endif /* #else #ifdef CONFIG_PREEMPT_RCU */
 
 /* Internal to kernel */
@@ -503,7 +515,14 @@ extern struct lockdep_map rcu_callback_map;
 int debug_lockdep_rcu_enabled(void);
 
 int rcu_read_lock_held(void);
+#ifdef CONFIG_PREEMPT_RT_FULL
+static inline int rcu_read_lock_bh_held(void)
+{
+       return rcu_read_lock_held();
+}
+#else
 int rcu_read_lock_bh_held(void);
+#endif
 
 /**
  * rcu_read_lock_sched_held() - might we be in RCU-sched read-side critical section?
@@ -624,54 +643,6 @@ static inline void rcu_preempt_sleep_check(void)
 })
 
 /**
- * RCU_INITIALIZER() - statically initialize an RCU-protected global variable
- * @v: The value to statically initialize with.
- */
-#define RCU_INITIALIZER(v) (typeof(*(v)) __force __rcu *)(v)
-
-/**
- * rcu_assign_pointer() - assign to RCU-protected pointer
- * @p: pointer to assign to
- * @v: value to assign (publish)
- *
- * Assigns the specified value to the specified RCU-protected
- * pointer, ensuring that any concurrent RCU readers will see
- * any prior initialization.
- *
- * Inserts memory barriers on architectures that require them
- * (which is most of them), and also prevents the compiler from
- * reordering the code that initializes the structure after the pointer
- * assignment.  More importantly, this call documents which pointers
- * will be dereferenced by RCU read-side code.
- *
- * In some special cases, you may use RCU_INIT_POINTER() instead
- * of rcu_assign_pointer().  RCU_INIT_POINTER() is a bit faster due
- * to the fact that it does not constrain either the CPU or the compiler.
- * That said, using RCU_INIT_POINTER() when you should have used
- * rcu_assign_pointer() is a very bad thing that results in
- * impossible-to-diagnose memory corruption.  So please be careful.
- * See the RCU_INIT_POINTER() comment header for details.
- *
- * Note that rcu_assign_pointer() evaluates each of its arguments only
- * once, appearances notwithstanding.  One of the "extra" evaluations
- * is in typeof() and the other visible only to sparse (__CHECKER__),
- * neither of which actually execute the argument.  As with most cpp
- * macros, this execute-arguments-only-once property is important, so
- * please be careful when making changes to rcu_assign_pointer() and the
- * other macros that it invokes.
- */
-#define rcu_assign_pointer(p, v)                                             \
-({                                                                           \
-       uintptr_t _r_a_p__v = (uintptr_t)(v);                                 \
-                                                                             \
-       if (__builtin_constant_p(v) && (_r_a_p__v) == (uintptr_t)NULL)        \
-               WRITE_ONCE((p), (typeof(p))(_r_a_p__v));                      \
-       else                                                                  \
-               smp_store_release(&p, RCU_INITIALIZER((typeof(p))_r_a_p__v)); \
-       _r_a_p__v;                                                            \
-})
-
-/**
  * rcu_access_pointer() - fetch RCU pointer with no dereferencing
  * @p: The pointer to read
  *
@@ -949,10 +920,14 @@ static inline void rcu_read_unlock(void)
 static inline void rcu_read_lock_bh(void)
 {
        local_bh_disable();
+#ifdef CONFIG_PREEMPT_RT_FULL
+       rcu_read_lock();
+#else
        __acquire(RCU_BH);
        rcu_lock_acquire(&rcu_bh_lock_map);
        RCU_LOCKDEP_WARN(!rcu_is_watching(),
                         "rcu_read_lock_bh() used illegally while idle");
+#endif
 }
 
 /*
@@ -962,10 +937,14 @@ static inline void rcu_read_lock_bh(void)
  */
 static inline void rcu_read_unlock_bh(void)
 {
+#ifdef CONFIG_PREEMPT_RT_FULL
+       rcu_read_unlock();
+#else
        RCU_LOCKDEP_WARN(!rcu_is_watching(),
                         "rcu_read_unlock_bh() used illegally while idle");
        rcu_lock_release(&rcu_bh_lock_map);
        __release(RCU_BH);
+#endif
        local_bh_enable();
 }
 
index 63a4e4c..08ab12d 100644 (file)
@@ -44,7 +44,11 @@ static inline void rcu_virt_note_context_switch(int cpu)
        rcu_note_context_switch();
 }
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+# define synchronize_rcu_bh    synchronize_rcu
+#else
 void synchronize_rcu_bh(void);
+#endif
 void synchronize_sched_expedited(void);
 void synchronize_rcu_expedited(void);
 
@@ -72,7 +76,11 @@ static inline void synchronize_rcu_bh_expedited(void)
 }
 
 void rcu_barrier(void);
+#ifdef CONFIG_PREEMPT_RT_FULL
+# define rcu_barrier_bh                rcu_barrier
+#else
 void rcu_barrier_bh(void);
+#endif
 void rcu_barrier_sched(void);
 unsigned long get_state_synchronize_rcu(void);
 void cond_synchronize_rcu(unsigned long oldstate);
@@ -82,17 +90,14 @@ void cond_synchronize_sched(unsigned long oldstate);
 extern unsigned long rcutorture_testseq;
 extern unsigned long rcutorture_vernum;
 unsigned long rcu_batches_started(void);
-unsigned long rcu_batches_started_bh(void);
 unsigned long rcu_batches_started_sched(void);
 unsigned long rcu_batches_completed(void);
-unsigned long rcu_batches_completed_bh(void);
 unsigned long rcu_batches_completed_sched(void);
 unsigned long rcu_exp_batches_completed(void);
 unsigned long rcu_exp_batches_completed_sched(void);
 void show_rcu_gp_kthreads(void);
 
 void rcu_force_quiescent_state(void);
-void rcu_bh_force_quiescent_state(void);
 void rcu_sched_force_quiescent_state(void);
 
 void rcu_idle_enter(void);
@@ -109,6 +114,16 @@ extern int rcu_scheduler_active __read_mostly;
 
 bool rcu_is_watching(void);
 
+#ifndef CONFIG_PREEMPT_RT_FULL
+void rcu_bh_force_quiescent_state(void);
+unsigned long rcu_batches_started_bh(void);
+unsigned long rcu_batches_completed_bh(void);
+#else
+# define rcu_bh_force_quiescent_state  rcu_force_quiescent_state
+# define rcu_batches_completed_bh      rcu_batches_completed
+# define rcu_batches_started_bh                rcu_batches_completed
+#endif
+
 void rcu_all_qs(void);
 
 /* RCUtree hotplug events */
index 1abba5c..294a8b4 100644 (file)
 #define __LINUX_RT_MUTEX_H
 
 #include <linux/linkage.h>
+#include <linux/spinlock_types_raw.h>
 #include <linux/rbtree.h>
-#include <linux/spinlock_types.h>
 
 extern int max_lock_depth; /* for sysctl */
 
+#ifdef CONFIG_DEBUG_MUTEXES
+#include <linux/debug_locks.h>
+#endif
+
 /**
  * The rt_mutex structure
  *
@@ -31,8 +35,8 @@ struct rt_mutex {
        struct rb_root          waiters;
        struct rb_node          *waiters_leftmost;
        struct task_struct      *owner;
-#ifdef CONFIG_DEBUG_RT_MUTEXES
        int                     save_state;
+#ifdef CONFIG_DEBUG_RT_MUTEXES
        const char              *name, *file;
        int                     line;
        void                    *magic;
@@ -55,22 +59,33 @@ struct hrtimer_sleeper;
 # define rt_mutex_debug_check_no_locks_held(task)      do { } while (0)
 #endif
 
+# define rt_mutex_init(mutex)                                  \
+       do {                                                    \
+               raw_spin_lock_init(&(mutex)->wait_lock);        \
+               __rt_mutex_init(mutex, #mutex);                 \
+       } while (0)
+
 #ifdef CONFIG_DEBUG_RT_MUTEXES
 # define __DEBUG_RT_MUTEX_INITIALIZER(mutexname) \
        , .name = #mutexname, .file = __FILE__, .line = __LINE__
-# define rt_mutex_init(mutex)                  __rt_mutex_init(mutex, __func__)
  extern void rt_mutex_debug_task_free(struct task_struct *tsk);
 #else
 # define __DEBUG_RT_MUTEX_INITIALIZER(mutexname)
-# define rt_mutex_init(mutex)                  __rt_mutex_init(mutex, NULL)
 # define rt_mutex_debug_task_free(t)                   do { } while (0)
 #endif
 
-#define __RT_MUTEX_INITIALIZER(mutexname) \
-       { .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(mutexname.wait_lock) \
+#define __RT_MUTEX_INITIALIZER_PLAIN(mutexname) \
+        .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(mutexname.wait_lock) \
        , .waiters = RB_ROOT \
        , .owner = NULL \
-       __DEBUG_RT_MUTEX_INITIALIZER(mutexname)}
+       __DEBUG_RT_MUTEX_INITIALIZER(mutexname)
+
+#define __RT_MUTEX_INITIALIZER(mutexname) \
+       { __RT_MUTEX_INITIALIZER_PLAIN(mutexname) }
+
+#define __RT_MUTEX_INITIALIZER_SAVE_STATE(mutexname) \
+       { __RT_MUTEX_INITIALIZER_PLAIN(mutexname)    \
+       , .save_state = 1 }
 
 #define DEFINE_RT_MUTEX(mutexname) \
        struct rt_mutex mutexname = __RT_MUTEX_INITIALIZER(mutexname)
@@ -90,7 +105,9 @@ extern void __rt_mutex_init(struct rt_mutex *lock, const char *name);
 extern void rt_mutex_destroy(struct rt_mutex *lock);
 
 extern void rt_mutex_lock(struct rt_mutex *lock);
+extern int rt_mutex_lock_state(struct rt_mutex *lock, int state);
 extern int rt_mutex_lock_interruptible(struct rt_mutex *lock);
+extern int rt_mutex_lock_killable(struct rt_mutex *lock);
 extern int rt_mutex_timed_lock(struct rt_mutex *lock,
                               struct hrtimer_sleeper *timeout);
 
diff --git a/include/linux/rwlock_rt.h b/include/linux/rwlock_rt.h
new file mode 100644 (file)
index 0000000..49ed2d4
--- /dev/null
@@ -0,0 +1,99 @@
+#ifndef __LINUX_RWLOCK_RT_H
+#define __LINUX_RWLOCK_RT_H
+
+#ifndef __LINUX_SPINLOCK_H
+#error Do not include directly. Use spinlock.h
+#endif
+
+#define rwlock_init(rwl)                               \
+do {                                                   \
+       static struct lock_class_key __key;             \
+                                                       \
+       rt_mutex_init(&(rwl)->lock);                    \
+       __rt_rwlock_init(rwl, #rwl, &__key);            \
+} while (0)
+
+extern void __lockfunc rt_write_lock(rwlock_t *rwlock);
+extern void __lockfunc rt_read_lock(rwlock_t *rwlock);
+extern int __lockfunc rt_write_trylock(rwlock_t *rwlock);
+extern int __lockfunc rt_write_trylock_irqsave(rwlock_t *trylock, unsigned long *flags);
+extern int __lockfunc rt_read_trylock(rwlock_t *rwlock);
+extern void __lockfunc rt_write_unlock(rwlock_t *rwlock);
+extern void __lockfunc rt_read_unlock(rwlock_t *rwlock);
+extern unsigned long __lockfunc rt_write_lock_irqsave(rwlock_t *rwlock);
+extern unsigned long __lockfunc rt_read_lock_irqsave(rwlock_t *rwlock);
+extern void __rt_rwlock_init(rwlock_t *rwlock, char *name, struct lock_class_key *key);
+
+#define read_trylock(lock)     __cond_lock(lock, rt_read_trylock(lock))
+#define write_trylock(lock)    __cond_lock(lock, rt_write_trylock(lock))
+
+#define write_trylock_irqsave(lock, flags)     \
+       __cond_lock(lock, rt_write_trylock_irqsave(lock, &flags))
+
+#define read_lock_irqsave(lock, flags)                 \
+       do {                                            \
+               typecheck(unsigned long, flags);        \
+               flags = rt_read_lock_irqsave(lock);     \
+       } while (0)
+
+#define write_lock_irqsave(lock, flags)                        \
+       do {                                            \
+               typecheck(unsigned long, flags);        \
+               flags = rt_write_lock_irqsave(lock);    \
+       } while (0)
+
+#define read_lock(lock)                rt_read_lock(lock)
+
+#define read_lock_bh(lock)                             \
+       do {                                            \
+               local_bh_disable();                     \
+               rt_read_lock(lock);                     \
+       } while (0)
+
+#define read_lock_irq(lock)    read_lock(lock)
+
+#define write_lock(lock)       rt_write_lock(lock)
+
+#define write_lock_bh(lock)                            \
+       do {                                            \
+               local_bh_disable();                     \
+               rt_write_lock(lock);                    \
+       } while (0)
+
+#define write_lock_irq(lock)   write_lock(lock)
+
+#define read_unlock(lock)      rt_read_unlock(lock)
+
+#define read_unlock_bh(lock)                           \
+       do {                                            \
+               rt_read_unlock(lock);                   \
+               local_bh_enable();                      \
+       } while (0)
+
+#define read_unlock_irq(lock)  read_unlock(lock)
+
+#define write_unlock(lock)     rt_write_unlock(lock)
+
+#define write_unlock_bh(lock)                          \
+       do {                                            \
+               rt_write_unlock(lock);                  \
+               local_bh_enable();                      \
+       } while (0)
+
+#define write_unlock_irq(lock) write_unlock(lock)
+
+#define read_unlock_irqrestore(lock, flags)            \
+       do {                                            \
+               typecheck(unsigned long, flags);        \
+               (void) flags;                           \
+               rt_read_unlock(lock);                   \
+       } while (0)
+
+#define write_unlock_irqrestore(lock, flags) \
+       do {                                            \
+               typecheck(unsigned long, flags);        \
+               (void) flags;                           \
+               rt_write_unlock(lock);                  \
+       } while (0)
+
+#endif
index cc0072e..5317cd9 100644 (file)
@@ -1,6 +1,10 @@
 #ifndef __LINUX_RWLOCK_TYPES_H
 #define __LINUX_RWLOCK_TYPES_H
 
+#if !defined(__LINUX_SPINLOCK_TYPES_H)
+# error "Do not include directly, include spinlock_types.h"
+#endif
+
 /*
  * include/linux/rwlock_types.h - generic rwlock type definitions
  *                               and initializers
diff --git a/include/linux/rwlock_types_rt.h b/include/linux/rwlock_types_rt.h
new file mode 100644 (file)
index 0000000..51b28d7
--- /dev/null
@@ -0,0 +1,33 @@
+#ifndef __LINUX_RWLOCK_TYPES_RT_H
+#define __LINUX_RWLOCK_TYPES_RT_H
+
+#ifndef __LINUX_SPINLOCK_TYPES_H
+#error "Do not include directly. Include spinlock_types.h instead"
+#endif
+
+/*
+ * rwlocks - rtmutex which allows single reader recursion
+ */
+typedef struct {
+       struct rt_mutex         lock;
+       int                     read_depth;
+       unsigned int            break_lock;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+       struct lockdep_map      dep_map;
+#endif
+} rwlock_t;
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define RW_DEP_MAP_INIT(lockname)     .dep_map = { .name = #lockname }
+#else
+# define RW_DEP_MAP_INIT(lockname)
+#endif
+
+#define __RW_LOCK_UNLOCKED(name) \
+       { .lock = __RT_MUTEX_INITIALIZER_SAVE_STATE(name.lock), \
+         RW_DEP_MAP_INIT(name) }
+
+#define DEFINE_RWLOCK(name) \
+       rwlock_t name = __RW_LOCK_UNLOCKED(name)
+
+#endif
index dd1d142..aa2ac1f 100644 (file)
 #include <linux/osq_lock.h>
 #endif
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+#include <linux/rwsem_rt.h>
+#else /* PREEMPT_RT_FULL */
+
 struct rw_semaphore;
 
 #ifdef CONFIG_RWSEM_GENERIC_SPINLOCK
@@ -106,6 +110,13 @@ static inline int rwsem_is_contended(struct rw_semaphore *sem)
        return !list_empty(&sem->wait_list);
 }
 
+#endif /* !PREEMPT_RT_FULL */
+
+/*
+ * The functions below are the same for all rwsem implementations including
+ * the RT specific variant.
+ */
+
 /*
  * lock for reading
  */
diff --git a/include/linux/rwsem_rt.h b/include/linux/rwsem_rt.h
new file mode 100644 (file)
index 0000000..2ffbf09
--- /dev/null
@@ -0,0 +1,67 @@
+#ifndef _LINUX_RWSEM_RT_H
+#define _LINUX_RWSEM_RT_H
+
+#ifndef _LINUX_RWSEM_H
+#error "Include rwsem.h"
+#endif
+
+#include <linux/rtmutex.h>
+#include <linux/swait.h>
+
+#define READER_BIAS            (1U << 31)
+#define WRITER_BIAS            (1U << 30)
+
+struct rw_semaphore {
+       atomic_t                readers;
+       struct rt_mutex         rtmutex;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+       struct lockdep_map      dep_map;
+#endif
+};
+
+#define __RWSEM_INITIALIZER(name)                              \
+{                                                              \
+       .readers = ATOMIC_INIT(READER_BIAS),                    \
+       .rtmutex = __RT_MUTEX_INITIALIZER(name.rtmutex),        \
+       RW_DEP_MAP_INIT(name)                                   \
+}
+
+#define DECLARE_RWSEM(lockname) \
+       struct rw_semaphore lockname = __RWSEM_INITIALIZER(lockname)
+
+extern void  __rwsem_init(struct rw_semaphore *rwsem, const char *name,
+                         struct lock_class_key *key);
+
+#define __init_rwsem(sem, name, key)                   \
+do {                                                   \
+               rt_mutex_init(&(sem)->rtmutex);         \
+               __rwsem_init((sem), (name), (key));     \
+} while (0)
+
+#define init_rwsem(sem)                                        \
+do {                                                   \
+       static struct lock_class_key __key;             \
+                                                       \
+       __init_rwsem((sem), #sem, &__key);              \
+} while (0)
+
+static inline int rwsem_is_locked(struct rw_semaphore *sem)
+{
+       return atomic_read(&sem->readers) != READER_BIAS;
+}
+
+static inline int rwsem_is_contended(struct rw_semaphore *sem)
+{
+       return atomic_read(&sem->readers) > 0;
+}
+
+extern void __down_read(struct rw_semaphore *sem);
+extern int __down_read_trylock(struct rw_semaphore *sem);
+extern void __down_write(struct rw_semaphore *sem);
+extern int __must_check __down_write_killable(struct rw_semaphore *sem);
+extern int __down_write_trylock(struct rw_semaphore *sem);
+extern void __up_read(struct rw_semaphore *sem);
+extern void __up_write(struct rw_semaphore *sem);
+extern void __downgrade_write(struct rw_semaphore *sem);
+
+#endif
index a97f005..71dc768 100644 (file)
@@ -26,6 +26,7 @@ struct sched_param {
 #include <linux/nodemask.h>
 #include <linux/mm_types.h>
 #include <linux/preempt.h>
+#include <asm/kmap_types.h>
 
 #include <asm/page.h>
 #include <asm/ptrace.h>
@@ -239,17 +240,13 @@ extern char ___assert_task_state[1 - 2*!!(
 
 /* Convenience macros for the sake of wake_up */
 #define TASK_NORMAL            (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
-#define TASK_ALL               (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
 
 /* get_task_state() */
 #define TASK_REPORT            (TASK_RUNNING | TASK_INTERRUPTIBLE | \
                                 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
                                 __TASK_TRACED | EXIT_ZOMBIE | EXIT_DEAD)
 
-#define task_is_traced(task)   ((task->state & __TASK_TRACED) != 0)
 #define task_is_stopped(task)  ((task->state & __TASK_STOPPED) != 0)
-#define task_is_stopped_or_traced(task)        \
-                       ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
 #define task_contributes_to_load(task) \
                                ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
                                 (task->flags & PF_FROZEN) == 0 && \
@@ -315,6 +312,11 @@ extern char ___assert_task_state[1 - 2*!!(
 
 #endif
 
+#define __set_current_state_no_track(state_value)      \
+       do { current->state = (state_value); } while (0)
+#define set_current_state_no_track(state_value)                \
+       set_mb(current->state, (state_value))
+
 /* Task command name length */
 #define TASK_COMM_LEN 16
 
@@ -1043,9 +1045,31 @@ struct wake_q_head {
 #define WAKE_Q(name)                                   \
        struct wake_q_head name = { WAKE_Q_TAIL, &name.first }
 
-extern void wake_q_add(struct wake_q_head *head,
-                      struct task_struct *task);
-extern void wake_up_q(struct wake_q_head *head);
+extern void __wake_q_add(struct wake_q_head *head,
+                        struct task_struct *task, bool sleeper);
+static inline void wake_q_add(struct wake_q_head *head,
+                             struct task_struct *task)
+{
+       __wake_q_add(head, task, false);
+}
+
+static inline void wake_q_add_sleeper(struct wake_q_head *head,
+                                     struct task_struct *task)
+{
+       __wake_q_add(head, task, true);
+}
+
+extern void __wake_up_q(struct wake_q_head *head, bool sleeper);
+
+static inline void wake_up_q(struct wake_q_head *head)
+{
+       __wake_up_q(head, false);
+}
+
+static inline void wake_up_q_sleeper(struct wake_q_head *head)
+{
+       __wake_up_q(head, true);
+}
 
 /*
  * sched-domains (multiprocessor balancing) declarations:
@@ -1632,6 +1656,7 @@ struct task_struct {
        struct thread_info thread_info;
 #endif
        volatile long state;    /* -1 unrunnable, 0 runnable, >0 stopped */
+       volatile long saved_state; /* saved state for "spinlock sleepers" */
        void *stack;
        atomic_t usage;
        unsigned int flags;     /* per process flags, defined below */
@@ -1681,6 +1706,13 @@ struct task_struct {
 #endif
 
        unsigned int policy;
+#ifdef CONFIG_PREEMPT_RT_FULL
+       int migrate_disable;
+       int migrate_disable_update;
+# ifdef CONFIG_SCHED_DEBUG
+       int migrate_disable_atomic;
+# endif
+#endif
        int nr_cpus_allowed;
        cpumask_t cpus_allowed;
 
@@ -1823,6 +1855,9 @@ struct task_struct {
 
        struct task_cputime cputime_expires;
        struct list_head cpu_timers[3];
+#ifdef CONFIG_PREEMPT_RT_BASE
+       struct task_struct *posix_timer_list;
+#endif
 
 /* process credentials */
        const struct cred __rcu *ptracer_cred; /* Tracer's credentials at attach */
@@ -1854,10 +1889,15 @@ struct task_struct {
 /* signal handlers */
        struct signal_struct *signal;
        struct sighand_struct *sighand;
+       struct sigqueue *sigqueue_cache;
 
        sigset_t blocked, real_blocked;
        sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */
        struct sigpending pending;
+#ifdef CONFIG_PREEMPT_RT_FULL
+       /* TODO: move me into ->restart_block ? */
+       struct siginfo forced_info;
+#endif
 
        unsigned long sas_ss_sp;
        size_t sas_ss_size;
@@ -1883,11 +1923,14 @@ struct task_struct {
        raw_spinlock_t pi_lock;
 
        struct wake_q_node wake_q;
+       struct wake_q_node wake_q_sleeper;
 
 #ifdef CONFIG_RT_MUTEXES
        /* PI waiters blocked on a rt_mutex held by this task */
        struct rb_root pi_waiters;
        struct rb_node *pi_waiters_leftmost;
+       /* Updated under owner's pi_lock and rq lock */
+       struct task_struct      *pi_top_task;
        /* Deadlock detection and priority inheritance handling */
        struct rt_mutex_waiter *pi_blocked_on;
 #endif
@@ -2086,6 +2129,12 @@ struct task_struct {
        /* bitmask and counter of trace recursion */
        unsigned long trace_recursion;
 #endif /* CONFIG_TRACING */
+#ifdef CONFIG_WAKEUP_LATENCY_HIST
+       u64 preempt_timestamp_hist;
+#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
+       long timer_offset;
+#endif
+#endif
 #ifdef CONFIG_KCOV
        /* Coverage collection mode enabled for this task (0 if disabled). */
        enum kcov_mode kcov_mode;
@@ -2111,9 +2160,23 @@ struct task_struct {
        unsigned int    sequential_io;
        unsigned int    sequential_io_avg;
 #endif
+#ifdef CONFIG_PREEMPT_RT_BASE
+       struct rcu_head put_rcu;
+       int softirq_nestcnt;
+       unsigned int softirqs_raised;
+#endif
+#ifdef CONFIG_PREEMPT_RT_FULL
+# if defined CONFIG_HIGHMEM || defined CONFIG_X86_32
+       int kmap_idx;
+       pte_t kmap_pte[KM_TYPE_NR];
+# endif
+#endif
 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
        unsigned long   task_state_change;
 #endif
+#ifdef CONFIG_PREEMPT_RT_FULL
+       int xmit_recursion;
+#endif
        int pagefault_disabled;
 #ifdef CONFIG_MMU
        struct task_struct *oom_reaper_list;
@@ -2153,14 +2216,6 @@ static inline struct vm_struct *task_stack_vm_area(const struct task_struct *t)
 }
 #endif
 
-/* Future-safe accessor for struct task_struct's cpus_allowed. */
-#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
-
-static inline int tsk_nr_cpus_allowed(struct task_struct *p)
-{
-       return p->nr_cpus_allowed;
-}
-
 #define TNF_MIGRATED   0x01
 #define TNF_NO_GROUP   0x02
 #define TNF_SHARED     0x04
@@ -2380,6 +2435,15 @@ extern struct pid *cad_pid;
 extern void free_task(struct task_struct *tsk);
 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
 
+#ifdef CONFIG_PREEMPT_RT_BASE
+extern void __put_task_struct_cb(struct rcu_head *rhp);
+
+static inline void put_task_struct(struct task_struct *t)
+{
+       if (atomic_dec_and_test(&t->usage))
+               call_rcu(&t->put_rcu, __put_task_struct_cb);
+}
+#else
 extern void __put_task_struct(struct task_struct *t);
 
 static inline void put_task_struct(struct task_struct *t)
@@ -2387,6 +2451,7 @@ static inline void put_task_struct(struct task_struct *t)
        if (atomic_dec_and_test(&t->usage))
                __put_task_struct(t);
 }
+#endif
 
 struct task_struct *task_rcu_dereference(struct task_struct **ptask);
 struct task_struct *try_get_task_struct(struct task_struct **ptask);
@@ -2428,6 +2493,7 @@ extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut,
 /*
  * Per process flags
  */
+#define PF_IN_SOFTIRQ  0x00000001      /* Task is serving softirq */
 #define PF_EXITING     0x00000004      /* getting shut down */
 #define PF_EXITPIDONE  0x00000008      /* pi exit done on shut down */
 #define PF_VCPU                0x00000010      /* I'm a virtual CPU */
@@ -2614,6 +2680,10 @@ extern void do_set_cpus_allowed(struct task_struct *p,
 
 extern int set_cpus_allowed_ptr(struct task_struct *p,
                                const struct cpumask *new_mask);
+int migrate_me(void);
+void tell_sched_cpu_down_begin(int cpu);
+void tell_sched_cpu_down_done(int cpu);
+
 #else
 static inline void do_set_cpus_allowed(struct task_struct *p,
                                      const struct cpumask *new_mask)
@@ -2626,6 +2696,9 @@ static inline int set_cpus_allowed_ptr(struct task_struct *p,
                return -EINVAL;
        return 0;
 }
+static inline int migrate_me(void) { return 0; }
+static inline void tell_sched_cpu_down_begin(int cpu) { }
+static inline void tell_sched_cpu_down_done(int cpu) { }
 #endif
 
 #ifdef CONFIG_NO_HZ_COMMON
@@ -2864,6 +2937,7 @@ extern void xtime_update(unsigned long ticks);
 
 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
 extern int wake_up_process(struct task_struct *tsk);
+extern int wake_up_lock_sleeper(struct task_struct * tsk);
 extern void wake_up_new_task(struct task_struct *tsk);
 #ifdef CONFIG_SMP
  extern void kick_process(struct task_struct *tsk);
@@ -3072,6 +3146,17 @@ static inline void mmdrop(struct mm_struct *mm)
                __mmdrop(mm);
 }
 
+#ifdef CONFIG_PREEMPT_RT_BASE
+extern void __mmdrop_delayed(struct rcu_head *rhp);
+static inline void mmdrop_delayed(struct mm_struct *mm)
+{
+       if (atomic_dec_and_test(&mm->mm_count))
+               call_rcu(&mm->delayed_drop, __mmdrop_delayed);
+}
+#else
+# define mmdrop_delayed(mm)    mmdrop(mm)
+#endif
+
 static inline void mmdrop_async_fn(struct work_struct *work)
 {
        struct mm_struct *mm = container_of(work, struct mm_struct, async_put_work);
@@ -3481,6 +3566,43 @@ static inline int test_tsk_need_resched(struct task_struct *tsk)
        return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
 }
 
+#ifdef CONFIG_PREEMPT_LAZY
+static inline void set_tsk_need_resched_lazy(struct task_struct *tsk)
+{
+       set_tsk_thread_flag(tsk,TIF_NEED_RESCHED_LAZY);
+}
+
+static inline void clear_tsk_need_resched_lazy(struct task_struct *tsk)
+{
+       clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED_LAZY);
+}
+
+static inline int test_tsk_need_resched_lazy(struct task_struct *tsk)
+{
+       return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED_LAZY));
+}
+
+static inline int need_resched_lazy(void)
+{
+       return test_thread_flag(TIF_NEED_RESCHED_LAZY);
+}
+
+static inline int need_resched_now(void)
+{
+       return test_thread_flag(TIF_NEED_RESCHED);
+}
+
+#else
+static inline void clear_tsk_need_resched_lazy(struct task_struct *tsk) { }
+static inline int need_resched_lazy(void) { return 0; }
+
+static inline int need_resched_now(void)
+{
+       return test_thread_flag(TIF_NEED_RESCHED);
+}
+
+#endif
+
 static inline int restart_syscall(void)
 {
        set_tsk_thread_flag(current, TIF_SIGPENDING);
@@ -3512,6 +3634,51 @@ static inline int signal_pending_state(long state, struct task_struct *p)
        return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
 }
 
+static inline bool __task_is_stopped_or_traced(struct task_struct *task)
+{
+       if (task->state & (__TASK_STOPPED | __TASK_TRACED))
+               return true;
+#ifdef CONFIG_PREEMPT_RT_FULL
+       if (task->saved_state & (__TASK_STOPPED | __TASK_TRACED))
+               return true;
+#endif
+       return false;
+}
+
+static inline bool task_is_stopped_or_traced(struct task_struct *task)
+{
+       bool traced_stopped;
+
+#ifdef CONFIG_PREEMPT_RT_FULL
+       unsigned long flags;
+
+       raw_spin_lock_irqsave(&task->pi_lock, flags);
+       traced_stopped = __task_is_stopped_or_traced(task);
+       raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+#else
+       traced_stopped = __task_is_stopped_or_traced(task);
+#endif
+       return traced_stopped;
+}
+
+static inline bool task_is_traced(struct task_struct *task)
+{
+       bool traced = false;
+
+       if (task->state & __TASK_TRACED)
+               return true;
+#ifdef CONFIG_PREEMPT_RT_FULL
+       /* in case the task is sleeping on tasklist_lock */
+       raw_spin_lock_irq(&task->pi_lock);
+       if (task->state & __TASK_TRACED)
+               traced = true;
+       else if (task->saved_state & __TASK_TRACED)
+               traced = true;
+       raw_spin_unlock_irq(&task->pi_lock);
+#endif
+       return traced;
+}
+
 /*
  * cond_resched() and cond_resched_lock(): latency reduction via
  * explicit rescheduling in places that are safe. The return
@@ -3537,12 +3704,16 @@ extern int __cond_resched_lock(spinlock_t *lock);
        __cond_resched_lock(lock);                              \
 })
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 extern int __cond_resched_softirq(void);
 
 #define cond_resched_softirq() ({                                      \
        ___might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET);     \
        __cond_resched_softirq();                                       \
 })
+#else
+# define cond_resched_softirq()                cond_resched()
+#endif
 
 static inline void cond_resched_rcu(void)
 {
@@ -3717,6 +3888,31 @@ static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
 
 #endif /* CONFIG_SMP */
 
+static inline int __migrate_disabled(struct task_struct *p)
+{
+#ifdef CONFIG_PREEMPT_RT_FULL
+       return p->migrate_disable;
+#else
+       return 0;
+#endif
+}
+
+/* Future-safe accessor for struct task_struct's cpus_allowed. */
+static inline const struct cpumask *tsk_cpus_allowed(struct task_struct *p)
+{
+       if (__migrate_disabled(p))
+               return cpumask_of(task_cpu(p));
+
+       return &p->cpus_allowed;
+}
+
+static inline int tsk_nr_cpus_allowed(struct task_struct *p)
+{
+       if (__migrate_disabled(p))
+               return 1;
+       return p->nr_cpus_allowed;
+}
+
 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
 
index a30b172..db3e91f 100644 (file)
@@ -16,27 +16,20 @@ static inline int rt_task(struct task_struct *p)
 }
 
 #ifdef CONFIG_RT_MUTEXES
-extern int rt_mutex_getprio(struct task_struct *p);
-extern void rt_mutex_setprio(struct task_struct *p, int prio);
-extern int rt_mutex_get_effective_prio(struct task_struct *task, int newprio);
-extern struct task_struct *rt_mutex_get_top_task(struct task_struct *task);
+/*
+ * Must hold either p->pi_lock or task_rq(p)->lock.
+ */
+static inline struct task_struct *rt_mutex_get_top_task(struct task_struct *p)
+{
+       return p->pi_top_task;
+}
+extern void rt_mutex_setprio(struct task_struct *p, struct task_struct *pi_task);
 extern void rt_mutex_adjust_pi(struct task_struct *p);
 static inline bool tsk_is_pi_blocked(struct task_struct *tsk)
 {
        return tsk->pi_blocked_on != NULL;
 }
 #else
-static inline int rt_mutex_getprio(struct task_struct *p)
-{
-       return p->normal_prio;
-}
-
-static inline int rt_mutex_get_effective_prio(struct task_struct *task,
-                                             int newprio)
-{
-       return newprio;
-}
-
 static inline struct task_struct *rt_mutex_get_top_task(struct task_struct *task)
 {
        return NULL;
index 1613fe5..961e07b 100644 (file)
@@ -220,20 +220,30 @@ static inline int read_seqcount_retry(const seqcount_t *s, unsigned start)
        return __read_seqcount_retry(s, start);
 }
 
-
-
-static inline void raw_write_seqcount_begin(seqcount_t *s)
+static inline void __raw_write_seqcount_begin(seqcount_t *s)
 {
        s->sequence++;
        smp_wmb();
 }
 
-static inline void raw_write_seqcount_end(seqcount_t *s)
+static inline void raw_write_seqcount_begin(seqcount_t *s)
+{
+       preempt_disable_rt();
+       __raw_write_seqcount_begin(s);
+}
+
+static inline void __raw_write_seqcount_end(seqcount_t *s)
 {
        smp_wmb();
        s->sequence++;
 }
 
+static inline void raw_write_seqcount_end(seqcount_t *s)
+{
+       __raw_write_seqcount_end(s);
+       preempt_enable_rt();
+}
+
 /**
  * raw_write_seqcount_barrier - do a seq write barrier
  * @s: pointer to seqcount_t
@@ -435,10 +445,33 @@ typedef struct {
 /*
  * Read side functions for starting and finalizing a read side section.
  */
+#ifndef CONFIG_PREEMPT_RT_FULL
 static inline unsigned read_seqbegin(const seqlock_t *sl)
 {
        return read_seqcount_begin(&sl->seqcount);
 }
+#else
+/*
+ * Starvation safe read side for RT
+ */
+static inline unsigned read_seqbegin(seqlock_t *sl)
+{
+       unsigned ret;
+
+repeat:
+       ret = ACCESS_ONCE(sl->seqcount.sequence);
+       if (unlikely(ret & 1)) {
+               /*
+                * Take the lock and let the writer proceed (i.e. evtl
+                * boost it), otherwise we could loop here forever.
+                */
+               spin_unlock_wait(&sl->lock);
+               goto repeat;
+       }
+       smp_rmb();
+       return ret;
+}
+#endif
 
 static inline unsigned read_seqretry(const seqlock_t *sl, unsigned start)
 {
@@ -453,36 +486,45 @@ static inline unsigned read_seqretry(const seqlock_t *sl, unsigned start)
 static inline void write_seqlock(seqlock_t *sl)
 {
        spin_lock(&sl->lock);
-       write_seqcount_begin(&sl->seqcount);
+       __raw_write_seqcount_begin(&sl->seqcount);
+}
+
+static inline int try_write_seqlock(seqlock_t *sl)
+{
+       if (spin_trylock(&sl->lock)) {
+               __raw_write_seqcount_begin(&sl->seqcount);
+               return 1;
+       }
+       return 0;
 }
 
 static inline void write_sequnlock(seqlock_t *sl)
 {
-       write_seqcount_end(&sl->seqcount);
+       __raw_write_seqcount_end(&sl->seqcount);
        spin_unlock(&sl->lock);
 }
 
 static inline void write_seqlock_bh(seqlock_t *sl)
 {
        spin_lock_bh(&sl->lock);
-       write_seqcount_begin(&sl->seqcount);
+       __raw_write_seqcount_begin(&sl->seqcount);
 }
 
 static inline void write_sequnlock_bh(seqlock_t *sl)
 {
-       write_seqcount_end(&sl->seqcount);
+       __raw_write_seqcount_end(&sl->seqcount);
        spin_unlock_bh(&sl->lock);
 }
 
 static inline void write_seqlock_irq(seqlock_t *sl)
 {
        spin_lock_irq(&sl->lock);
-       write_seqcount_begin(&sl->seqcount);
+       __raw_write_seqcount_begin(&sl->seqcount);
 }
 
 static inline void write_sequnlock_irq(seqlock_t *sl)
 {
-       write_seqcount_end(&sl->seqcount);
+       __raw_write_seqcount_end(&sl->seqcount);
        spin_unlock_irq(&sl->lock);
 }
 
@@ -491,7 +533,7 @@ static inline unsigned long __write_seqlock_irqsave(seqlock_t *sl)
        unsigned long flags;
 
        spin_lock_irqsave(&sl->lock, flags);
-       write_seqcount_begin(&sl->seqcount);
+       __raw_write_seqcount_begin(&sl->seqcount);
        return flags;
 }
 
@@ -501,7 +543,7 @@ static inline unsigned long __write_seqlock_irqsave(seqlock_t *sl)
 static inline void
 write_sequnlock_irqrestore(seqlock_t *sl, unsigned long flags)
 {
-       write_seqcount_end(&sl->seqcount);
+       __raw_write_seqcount_end(&sl->seqcount);
        spin_unlock_irqrestore(&sl->lock, flags);
 }
 
index ffa58ff..0d7faf6 100644 (file)
@@ -250,6 +250,7 @@ static inline void init_sigpending(struct sigpending *sig)
 }
 
 extern void flush_sigqueue(struct sigpending *queue);
+extern void flush_task_sigqueue(struct task_struct *tsk);
 
 /* Test if 'sig' is valid signal. Use this instead of testing _NSIG directly */
 static inline int valid_signal(unsigned long sig)
index 67b798b..4e78fd0 100644 (file)
@@ -284,6 +284,7 @@ struct sk_buff_head {
 
        __u32           qlen;
        spinlock_t      lock;
+       raw_spinlock_t  raw_lock;
 };
 
 struct sk_buff;
@@ -1591,6 +1592,12 @@ static inline void skb_queue_head_init(struct sk_buff_head *list)
        __skb_queue_head_init(list);
 }
 
+static inline void skb_queue_head_init_raw(struct sk_buff_head *list)
+{
+       raw_spin_lock_init(&list->raw_lock);
+       __skb_queue_head_init(list);
+}
+
 static inline void skb_queue_head_init_class(struct sk_buff_head *list,
                struct lock_class_key *class)
 {
index acba97e..cb3562f 100644 (file)
@@ -119,6 +119,13 @@ extern unsigned int setup_max_cpus;
 extern void __init setup_nr_cpu_ids(void);
 extern void __init smp_init(void);
 
+extern int __boot_cpu_id;
+
+static inline int get_boot_cpu_id(void)
+{
+       return __boot_cpu_id;
+}
+
 #else /* !SMP */
 
 static inline void smp_send_stop(void) { }
@@ -157,6 +164,11 @@ static inline void smp_init(void) { up_late_init(); }
 static inline void smp_init(void) { }
 #endif
 
+static inline int get_boot_cpu_id(void)
+{
+       return 0;
+}
+
 #endif /* !SMP */
 
 /*
@@ -184,6 +196,9 @@ static inline void smp_init(void) { }
 #define get_cpu()              ({ preempt_disable(); smp_processor_id(); })
 #define put_cpu()              preempt_enable()
 
+#define get_cpu_light()                ({ migrate_disable(); smp_processor_id(); })
+#define put_cpu_light()                migrate_enable()
+
 /*
  * Callback to arch code if there's nosmp or maxcpus=0 on the
  * boot command line:
index 47dd0ce..b241cc0 100644 (file)
@@ -271,7 +271,11 @@ static inline void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock)
 #define raw_spin_can_lock(lock)        (!raw_spin_is_locked(lock))
 
 /* Include rwlock functions */
-#include <linux/rwlock.h>
+#ifdef CONFIG_PREEMPT_RT_FULL
+# include <linux/rwlock_rt.h>
+#else
+# include <linux/rwlock.h>
+#endif
 
 /*
  * Pull the _spin_*()/_read_*()/_write_*() functions/declarations:
@@ -282,6 +286,10 @@ static inline void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock)
 # include <linux/spinlock_api_up.h>
 #endif
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+# include <linux/spinlock_rt.h>
+#else /* PREEMPT_RT_FULL */
+
 /*
  * Map the spin_lock functions to the raw variants for PREEMPT_RT=n
  */
@@ -416,4 +424,6 @@ extern int _atomic_dec_and_lock(atomic_t *atomic, spinlock_t *lock);
 #define atomic_dec_and_lock(atomic, lock) \
                __cond_lock(lock, _atomic_dec_and_lock(atomic, lock))
 
+#endif /* !PREEMPT_RT_FULL */
+
 #endif /* __LINUX_SPINLOCK_H */
index 5344268..043263f 100644 (file)
@@ -189,6 +189,8 @@ static inline int __raw_spin_trylock_bh(raw_spinlock_t *lock)
        return 0;
 }
 
-#include <linux/rwlock_api_smp.h>
+#ifndef CONFIG_PREEMPT_RT_FULL
+# include <linux/rwlock_api_smp.h>
+#endif
 
 #endif /* __LINUX_SPINLOCK_API_SMP_H */
diff --git a/include/linux/spinlock_rt.h b/include/linux/spinlock_rt.h
new file mode 100644 (file)
index 0000000..43ca841
--- /dev/null
@@ -0,0 +1,162 @@
+#ifndef __LINUX_SPINLOCK_RT_H
+#define __LINUX_SPINLOCK_RT_H
+
+#ifndef __LINUX_SPINLOCK_H
+#error Do not include directly. Use spinlock.h
+#endif
+
+#include <linux/bug.h>
+
+extern void
+__rt_spin_lock_init(spinlock_t *lock, char *name, struct lock_class_key *key);
+
+#define spin_lock_init(slock)                          \
+do {                                                   \
+       static struct lock_class_key __key;             \
+                                                       \
+       rt_mutex_init(&(slock)->lock);                  \
+       __rt_spin_lock_init(slock, #slock, &__key);     \
+} while (0)
+
+void __lockfunc rt_spin_lock__no_mg(spinlock_t *lock);
+void __lockfunc rt_spin_unlock__no_mg(spinlock_t *lock);
+int __lockfunc rt_spin_trylock__no_mg(spinlock_t *lock);
+
+extern void __lockfunc rt_spin_lock(spinlock_t *lock);
+extern unsigned long __lockfunc rt_spin_lock_trace_flags(spinlock_t *lock);
+extern void __lockfunc rt_spin_lock_nested(spinlock_t *lock, int subclass);
+extern void __lockfunc rt_spin_unlock(spinlock_t *lock);
+extern void __lockfunc rt_spin_unlock_wait(spinlock_t *lock);
+extern int __lockfunc rt_spin_trylock_irqsave(spinlock_t *lock, unsigned long *flags);
+extern int __lockfunc rt_spin_trylock_bh(spinlock_t *lock);
+extern int __lockfunc rt_spin_trylock(spinlock_t *lock);
+extern int atomic_dec_and_spin_lock(atomic_t *atomic, spinlock_t *lock);
+
+/*
+ * lockdep-less calls, for derived types like rwlock:
+ * (for trylock they can use rt_mutex_trylock() directly.
+ */
+extern void __lockfunc __rt_spin_lock__no_mg(struct rt_mutex *lock);
+extern void __lockfunc __rt_spin_lock(struct rt_mutex *lock);
+extern void __lockfunc __rt_spin_unlock(struct rt_mutex *lock);
+
+#define spin_lock(lock)                        rt_spin_lock(lock)
+
+#define spin_lock_bh(lock)                     \
+       do {                                    \
+               local_bh_disable();             \
+               rt_spin_lock(lock);             \
+       } while (0)
+
+#define spin_lock_irq(lock)            spin_lock(lock)
+
+#define spin_do_trylock(lock)          __cond_lock(lock, rt_spin_trylock(lock))
+
+#define spin_trylock(lock)                     \
+({                                             \
+       int __locked;                           \
+       __locked = spin_do_trylock(lock);       \
+       __locked;                               \
+})
+
+#ifdef CONFIG_LOCKDEP
+# define spin_lock_nested(lock, subclass)              \
+       do {                                            \
+               rt_spin_lock_nested(lock, subclass);    \
+       } while (0)
+
+#define spin_lock_bh_nested(lock, subclass)            \
+       do {                                            \
+               local_bh_disable();                     \
+               rt_spin_lock_nested(lock, subclass);    \
+       } while (0)
+
+# define spin_lock_irqsave_nested(lock, flags, subclass) \
+       do {                                             \
+               typecheck(unsigned long, flags);         \
+               flags = 0;                               \
+               rt_spin_lock_nested(lock, subclass);     \
+       } while (0)
+#else
+# define spin_lock_nested(lock, subclass)      spin_lock(lock)
+# define spin_lock_bh_nested(lock, subclass)   spin_lock_bh(lock)
+
+# define spin_lock_irqsave_nested(lock, flags, subclass) \
+       do {                                             \
+               typecheck(unsigned long, flags);         \
+               flags = 0;                               \
+               spin_lock(lock);                         \
+       } while (0)
+#endif
+
+#define spin_lock_irqsave(lock, flags)                  \
+       do {                                             \
+               typecheck(unsigned long, flags);         \
+               flags = 0;                               \
+               spin_lock(lock);                         \
+       } while (0)
+
+static inline unsigned long spin_lock_trace_flags(spinlock_t *lock)
+{
+       unsigned long flags = 0;
+#ifdef CONFIG_TRACE_IRQFLAGS
+       flags = rt_spin_lock_trace_flags(lock);
+#else
+       spin_lock(lock); /* lock_local */
+#endif
+       return flags;
+}
+
+/* FIXME: we need rt_spin_lock_nest_lock */
+#define spin_lock_nest_lock(lock, nest_lock) spin_lock_nested(lock, 0)
+
+#define spin_unlock(lock)                      rt_spin_unlock(lock)
+
+#define spin_unlock_bh(lock)                           \
+       do {                                            \
+               rt_spin_unlock(lock);                   \
+               local_bh_enable();                      \
+       } while (0)
+
+#define spin_unlock_irq(lock)          spin_unlock(lock)
+
+#define spin_unlock_irqrestore(lock, flags)            \
+       do {                                            \
+               typecheck(unsigned long, flags);        \
+               (void) flags;                           \
+               spin_unlock(lock);                      \
+       } while (0)
+
+#define spin_trylock_bh(lock)  __cond_lock(lock, rt_spin_trylock_bh(lock))
+#define spin_trylock_irq(lock) spin_trylock(lock)
+
+#define spin_trylock_irqsave(lock, flags)      \
+       rt_spin_trylock_irqsave(lock, &(flags))
+
+#define spin_unlock_wait(lock)         rt_spin_unlock_wait(lock)
+
+#ifdef CONFIG_GENERIC_LOCKBREAK
+# define spin_is_contended(lock)       ((lock)->break_lock)
+#else
+# define spin_is_contended(lock)       (((void)(lock), 0))
+#endif
+
+static inline int spin_can_lock(spinlock_t *lock)
+{
+       return !rt_mutex_is_locked(&lock->lock);
+}
+
+static inline int spin_is_locked(spinlock_t *lock)
+{
+       return rt_mutex_is_locked(&lock->lock);
+}
+
+static inline void assert_spin_locked(spinlock_t *lock)
+{
+       BUG_ON(!spin_is_locked(lock));
+}
+
+#define atomic_dec_and_lock(atomic, lock) \
+       atomic_dec_and_spin_lock(atomic, lock)
+
+#endif
index 73548eb..10bac71 100644 (file)
@@ -9,80 +9,15 @@
  * Released under the General Public License (GPL).
  */
 
-#if defined(CONFIG_SMP)
-# include <asm/spinlock_types.h>
-#else
-# include <linux/spinlock_types_up.h>
-#endif
-
-#include <linux/lockdep.h>
-
-typedef struct raw_spinlock {
-       arch_spinlock_t raw_lock;
-#ifdef CONFIG_GENERIC_LOCKBREAK
-       unsigned int break_lock;
-#endif
-#ifdef CONFIG_DEBUG_SPINLOCK
-       unsigned int magic, owner_cpu;
-       void *owner;
-#endif
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-       struct lockdep_map dep_map;
-#endif
-} raw_spinlock_t;
-
-#define SPINLOCK_MAGIC         0xdead4ead
-
-#define SPINLOCK_OWNER_INIT    ((void *)-1L)
-
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# define SPIN_DEP_MAP_INIT(lockname)   .dep_map = { .name = #lockname }
-#else
-# define SPIN_DEP_MAP_INIT(lockname)
-#endif
+#include <linux/spinlock_types_raw.h>
 
-#ifdef CONFIG_DEBUG_SPINLOCK
-# define SPIN_DEBUG_INIT(lockname)             \
-       .magic = SPINLOCK_MAGIC,                \
-       .owner_cpu = -1,                        \
-       .owner = SPINLOCK_OWNER_INIT,
+#ifndef CONFIG_PREEMPT_RT_FULL
+# include <linux/spinlock_types_nort.h>
+# include <linux/rwlock_types.h>
 #else
-# define SPIN_DEBUG_INIT(lockname)
+# include <linux/rtmutex.h>
+# include <linux/spinlock_types_rt.h>
+# include <linux/rwlock_types_rt.h>
 #endif
 
-#define __RAW_SPIN_LOCK_INITIALIZER(lockname)  \
-       {                                       \
-       .raw_lock = __ARCH_SPIN_LOCK_UNLOCKED,  \
-       SPIN_DEBUG_INIT(lockname)               \
-       SPIN_DEP_MAP_INIT(lockname) }
-
-#define __RAW_SPIN_LOCK_UNLOCKED(lockname)     \
-       (raw_spinlock_t) __RAW_SPIN_LOCK_INITIALIZER(lockname)
-
-#define DEFINE_RAW_SPINLOCK(x) raw_spinlock_t x = __RAW_SPIN_LOCK_UNLOCKED(x)
-
-typedef struct spinlock {
-       union {
-               struct raw_spinlock rlock;
-
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# define LOCK_PADSIZE (offsetof(struct raw_spinlock, dep_map))
-               struct {
-                       u8 __padding[LOCK_PADSIZE];
-                       struct lockdep_map dep_map;
-               };
-#endif
-       };
-} spinlock_t;
-
-#define __SPIN_LOCK_INITIALIZER(lockname) \
-       { { .rlock = __RAW_SPIN_LOCK_INITIALIZER(lockname) } }
-
-#define __SPIN_LOCK_UNLOCKED(lockname) \
-       (spinlock_t ) __SPIN_LOCK_INITIALIZER(lockname)
-
-#define DEFINE_SPINLOCK(x)     spinlock_t x = __SPIN_LOCK_UNLOCKED(x)
-
-#include <linux/rwlock_types.h>
-
 #endif /* __LINUX_SPINLOCK_TYPES_H */
diff --git a/include/linux/spinlock_types_nort.h b/include/linux/spinlock_types_nort.h
new file mode 100644 (file)
index 0000000..f1dac1f
--- /dev/null
@@ -0,0 +1,33 @@
+#ifndef __LINUX_SPINLOCK_TYPES_NORT_H
+#define __LINUX_SPINLOCK_TYPES_NORT_H
+
+#ifndef __LINUX_SPINLOCK_TYPES_H
+#error "Do not include directly. Include spinlock_types.h instead"
+#endif
+
+/*
+ * The non RT version maps spinlocks to raw_spinlocks
+ */
+typedef struct spinlock {
+       union {
+               struct raw_spinlock rlock;
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define LOCK_PADSIZE (offsetof(struct raw_spinlock, dep_map))
+               struct {
+                       u8 __padding[LOCK_PADSIZE];
+                       struct lockdep_map dep_map;
+               };
+#endif
+       };
+} spinlock_t;
+
+#define __SPIN_LOCK_INITIALIZER(lockname) \
+       { { .rlock = __RAW_SPIN_LOCK_INITIALIZER(lockname) } }
+
+#define __SPIN_LOCK_UNLOCKED(lockname) \
+       (spinlock_t ) __SPIN_LOCK_INITIALIZER(lockname)
+
+#define DEFINE_SPINLOCK(x)     spinlock_t x = __SPIN_LOCK_UNLOCKED(x)
+
+#endif
diff --git a/include/linux/spinlock_types_raw.h b/include/linux/spinlock_types_raw.h
new file mode 100644 (file)
index 0000000..03235b4
--- /dev/null
@@ -0,0 +1,58 @@
+#ifndef __LINUX_SPINLOCK_TYPES_RAW_H
+#define __LINUX_SPINLOCK_TYPES_RAW_H
+
+#include <linux/types.h>
+
+#if defined(CONFIG_SMP)
+# include <asm/spinlock_types.h>
+#else
+# include <linux/spinlock_types_up.h>
+#endif
+
+#include <linux/lockdep.h>
+
+typedef struct raw_spinlock {
+       arch_spinlock_t raw_lock;
+#ifdef CONFIG_GENERIC_LOCKBREAK
+       unsigned int break_lock;
+#endif
+#ifdef CONFIG_DEBUG_SPINLOCK
+       unsigned int magic, owner_cpu;
+       void *owner;
+#endif
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+       struct lockdep_map dep_map;
+#endif
+} raw_spinlock_t;
+
+#define SPINLOCK_MAGIC         0xdead4ead
+
+#define SPINLOCK_OWNER_INIT    ((void *)-1L)
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define SPIN_DEP_MAP_INIT(lockname)   .dep_map = { .name = #lockname }
+#else
+# define SPIN_DEP_MAP_INIT(lockname)
+#endif
+
+#ifdef CONFIG_DEBUG_SPINLOCK
+# define SPIN_DEBUG_INIT(lockname)             \
+       .magic = SPINLOCK_MAGIC,                \
+       .owner_cpu = -1,                        \
+       .owner = SPINLOCK_OWNER_INIT,
+#else
+# define SPIN_DEBUG_INIT(lockname)
+#endif
+
+#define __RAW_SPIN_LOCK_INITIALIZER(lockname)  \
+       {                                       \
+       .raw_lock = __ARCH_SPIN_LOCK_UNLOCKED,  \
+       SPIN_DEBUG_INIT(lockname)               \
+       SPIN_DEP_MAP_INIT(lockname) }
+
+#define __RAW_SPIN_LOCK_UNLOCKED(lockname)     \
+       (raw_spinlock_t) __RAW_SPIN_LOCK_INITIALIZER(lockname)
+
+#define DEFINE_RAW_SPINLOCK(x) raw_spinlock_t x = __RAW_SPIN_LOCK_UNLOCKED(x)
+
+#endif
diff --git a/include/linux/spinlock_types_rt.h b/include/linux/spinlock_types_rt.h
new file mode 100644 (file)
index 0000000..3e3d8c5
--- /dev/null
@@ -0,0 +1,48 @@
+#ifndef __LINUX_SPINLOCK_TYPES_RT_H
+#define __LINUX_SPINLOCK_TYPES_RT_H
+
+#ifndef __LINUX_SPINLOCK_TYPES_H
+#error "Do not include directly. Include spinlock_types.h instead"
+#endif
+
+#include <linux/cache.h>
+
+/*
+ * PREEMPT_RT: spinlocks - an RT mutex plus lock-break field:
+ */
+typedef struct spinlock {
+       struct rt_mutex         lock;
+       unsigned int            break_lock;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+       struct lockdep_map      dep_map;
+#endif
+} spinlock_t;
+
+#ifdef CONFIG_DEBUG_RT_MUTEXES
+# define __RT_SPIN_INITIALIZER(name) \
+       { \
+       .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(name.wait_lock), \
+       .save_state = 1, \
+       .file = __FILE__, \
+       .line = __LINE__ , \
+       }
+#else
+# define __RT_SPIN_INITIALIZER(name) \
+       {                                                               \
+       .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(name.wait_lock),          \
+       .save_state = 1, \
+       }
+#endif
+
+/*
+.wait_list = PLIST_HEAD_INIT_RAW((name).lock.wait_list, (name).lock.wait_lock)
+*/
+
+#define __SPIN_LOCK_UNLOCKED(name)                     \
+       { .lock = __RT_SPIN_INITIALIZER(name.lock),             \
+         SPIN_DEP_MAP_INIT(name) }
+
+#define DEFINE_SPINLOCK(name) \
+       spinlock_t name = __SPIN_LOCK_UNLOCKED(name)
+
+#endif
index dc8eb63..e793d3a 100644 (file)
@@ -84,10 +84,10 @@ int init_srcu_struct(struct srcu_struct *sp);
 
 void process_srcu(struct work_struct *work);
 
-#define __SRCU_STRUCT_INIT(name)                                       \
+#define __SRCU_STRUCT_INIT(name, pcpu_name)                            \
        {                                                               \
                .completed = -300,                                      \
-               .per_cpu_ref = &name##_srcu_array,                      \
+               .per_cpu_ref = &pcpu_name,                              \
                .queue_lock = __SPIN_LOCK_UNLOCKED(name.queue_lock),    \
                .running = false,                                       \
                .batch_queue = RCU_BATCH_INIT(name.batch_queue),        \
@@ -119,7 +119,7 @@ void process_srcu(struct work_struct *work);
  */
 #define __DEFINE_SRCU(name, is_static)                                 \
        static DEFINE_PER_CPU(struct srcu_struct_array, name##_srcu_array);\
-       is_static struct srcu_struct name = __SRCU_STRUCT_INIT(name)
+       is_static struct srcu_struct name = __SRCU_STRUCT_INIT(name, name##_srcu_array)
 #define DEFINE_SRCU(name)              __DEFINE_SRCU(name, /* not static */)
 #define DEFINE_STATIC_SRCU(name)       __DEFINE_SRCU(name, static)
 
index 90d8569..9009d26 100644 (file)
@@ -193,6 +193,12 @@ struct platform_freeze_ops {
        void (*end)(void);
 };
 
+#if defined(CONFIG_SUSPEND) || defined(CONFIG_HIBERNATION)
+extern bool pm_in_action;
+#else
+# define pm_in_action false
+#endif
+
 #ifdef CONFIG_SUSPEND
 /**
  * suspend_set_ops - set platform dependent suspend operations
index c1f9c62..83f004a 100644 (file)
@@ -87,6 +87,7 @@ static inline int swait_active(struct swait_queue_head *q)
 extern void swake_up(struct swait_queue_head *q);
 extern void swake_up_all(struct swait_queue_head *q);
 extern void swake_up_locked(struct swait_queue_head *q);
+extern void swake_up_all_locked(struct swait_queue_head *q);
 
 extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);
 extern void prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait, int state);
index d13617c..0986230 100644 (file)
@@ -11,6 +11,7 @@
 #include <linux/fs.h>
 #include <linux/atomic.h>
 #include <linux/page-flags.h>
+#include <linux/locallock.h>
 #include <asm/page.h>
 
 struct notifier_block;
@@ -247,7 +248,8 @@ struct swap_info_struct {
 void *workingset_eviction(struct address_space *mapping, struct page *page);
 bool workingset_refault(void *shadow);
 void workingset_activation(struct page *page);
-extern struct list_lru workingset_shadow_nodes;
+extern struct list_lru __workingset_shadow_nodes;
+DECLARE_LOCAL_IRQ_LOCK(workingset_shadow_lock);
 
 static inline unsigned int workingset_node_pages(struct radix_tree_node *node)
 {
@@ -292,6 +294,7 @@ extern unsigned long nr_free_pagecache_pages(void);
 
 
 /* linux/mm/swap.c */
+DECLARE_LOCAL_IRQ_LOCK(swapvec_lock);
 extern void lru_cache_add(struct page *);
 extern void lru_cache_add_anon(struct page *page);
 extern void lru_cache_add_file(struct page *page);
diff --git a/include/linux/swork.h b/include/linux/swork.h
new file mode 100644 (file)
index 0000000..f175fa9
--- /dev/null
@@ -0,0 +1,24 @@
+#ifndef _LINUX_SWORK_H
+#define _LINUX_SWORK_H
+
+#include <linux/list.h>
+
+struct swork_event {
+       struct list_head item;
+       unsigned long flags;
+       void (*func)(struct swork_event *);
+};
+
+static inline void INIT_SWORK(struct swork_event *event,
+                             void (*func)(struct swork_event *))
+{
+       event->flags = 0;
+       event->func = func;
+}
+
+bool swork_queue(struct swork_event *sev);
+
+int swork_get(void);
+void swork_put(void);
+
+#endif /* _LINUX_SWORK_H */
index ce98a8e..61fc8c2 100644 (file)
@@ -69,7 +69,17 @@ static inline int test_ti_thread_flag(struct thread_info *ti, int flag)
 #define test_thread_flag(flag) \
        test_ti_thread_flag(current_thread_info(), flag)
 
-#define tif_need_resched() test_thread_flag(TIF_NEED_RESCHED)
+#ifdef CONFIG_PREEMPT_LAZY
+#define tif_need_resched()     (test_thread_flag(TIF_NEED_RESCHED) || \
+                                test_thread_flag(TIF_NEED_RESCHED_LAZY))
+#define tif_need_resched_now() (test_thread_flag(TIF_NEED_RESCHED))
+#define tif_need_resched_lazy()        test_thread_flag(TIF_NEED_RESCHED_LAZY))
+
+#else
+#define tif_need_resched()     test_thread_flag(TIF_NEED_RESCHED)
+#define tif_need_resched_now() test_thread_flag(TIF_NEED_RESCHED)
+#define tif_need_resched_lazy()        0
+#endif
 
 #ifndef CONFIG_HAVE_ARCH_WITHIN_STACK_FRAMES
 static inline int arch_within_stack_frames(const void * const stack,
index ec86e4e..8e5b680 100644 (file)
@@ -241,7 +241,7 @@ extern void add_timer(struct timer_list *timer);
 
 extern int try_to_del_timer_sync(struct timer_list *timer);
 
-#ifdef CONFIG_SMP
+#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT_FULL)
   extern int del_timer_sync(struct timer_list *timer);
 #else
 # define del_timer_sync(t)             del_timer(t)
index ba57266..5c36934 100644 (file)
@@ -56,6 +56,9 @@ struct trace_entry {
        unsigned char           flags;
        unsigned char           preempt_count;
        int                     pid;
+       unsigned short          migrate_disable;
+       unsigned short          padding;
+       unsigned char           preempt_lazy_count;
 };
 
 #define TRACE_EVENT_TYPE_MAX                                           \
index cc5ba47..8451f7e 100644 (file)
@@ -27,6 +27,7 @@ static __always_inline void pagefault_disabled_dec(void)
  */
 static inline void pagefault_disable(void)
 {
+       migrate_disable();
        pagefault_disabled_inc();
        /*
         * make sure to have issued the store before a pagefault
@@ -43,6 +44,7 @@ static inline void pagefault_enable(void)
         */
        barrier();
        pagefault_disabled_dec();
+       migrate_enable();
 }
 
 /*
index 4a29c75..0a294e9 100644 (file)
@@ -27,6 +27,7 @@
 #include <linux/errno.h>
 #include <linux/rbtree.h>
 #include <linux/types.h>
+#include <linux/wait.h>
 
 struct vm_area_struct;
 struct mm_struct;
index c9a3343..af63f66 100644 (file)
@@ -35,7 +35,9 @@ DECLARE_PER_CPU(struct vm_event_state, vm_event_states);
  */
 static inline void __count_vm_event(enum vm_event_item item)
 {
+       preempt_disable_rt();
        raw_cpu_inc(vm_event_states.event[item]);
+       preempt_enable_rt();
 }
 
 static inline void count_vm_event(enum vm_event_item item)
@@ -45,7 +47,9 @@ static inline void count_vm_event(enum vm_event_item item)
 
 static inline void __count_vm_events(enum vm_event_item item, long delta)
 {
+       preempt_disable_rt();
        raw_cpu_add(vm_event_states.event[item], delta);
+       preempt_enable_rt();
 }
 
 static inline void count_vm_events(enum vm_event_item item, long delta)
index 2408e8d..db50d66 100644 (file)
@@ -8,6 +8,7 @@
 #include <linux/spinlock.h>
 #include <asm/current.h>
 #include <uapi/linux/wait.h>
+#include <linux/atomic.h>
 
 typedef struct __wait_queue wait_queue_t;
 typedef int (*wait_queue_func_t)(wait_queue_t *wait, unsigned mode, int flags, void *key);
index 12247c0..37d79ab 100644 (file)
@@ -452,7 +452,7 @@ static inline void dst_confirm(struct dst_entry *dst)
 static inline int dst_neigh_output(struct dst_entry *dst, struct neighbour *n,
                                   struct sk_buff *skb)
 {
-       const struct hh_cache *hh;
+       struct hh_cache *hh;
 
        if (dst->pending_confirm) {
                unsigned long now = jiffies;
index 231e121..d125222 100644 (file)
@@ -5,6 +5,7 @@
 #include <linux/socket.h>
 #include <linux/rtnetlink.h>
 #include <linux/pkt_sched.h>
+#include <net/net_seq_lock.h>
 
 struct gnet_stats_basic_cpu {
        struct gnet_stats_basic_packed bstats;
@@ -33,11 +34,11 @@ int gnet_stats_start_copy_compat(struct sk_buff *skb, int type,
                                 spinlock_t *lock, struct gnet_dump *d,
                                 int padattr);
 
-int gnet_stats_copy_basic(const seqcount_t *running,
+int gnet_stats_copy_basic(net_seqlock_t *running,
                          struct gnet_dump *d,
                          struct gnet_stats_basic_cpu __percpu *cpu,
                          struct gnet_stats_basic_packed *b);
-void __gnet_stats_copy_basic(const seqcount_t *running,
+void __gnet_stats_copy_basic(net_seqlock_t *running,
                             struct gnet_stats_basic_packed *bstats,
                             struct gnet_stats_basic_cpu __percpu *cpu,
                             struct gnet_stats_basic_packed *b);
@@ -55,14 +56,14 @@ int gen_new_estimator(struct gnet_stats_basic_packed *bstats,
                      struct gnet_stats_basic_cpu __percpu *cpu_bstats,
                      struct gnet_stats_rate_est64 *rate_est,
                      spinlock_t *stats_lock,
-                     seqcount_t *running, struct nlattr *opt);
+                     net_seqlock_t *running, struct nlattr *opt);
 void gen_kill_estimator(struct gnet_stats_basic_packed *bstats,
                        struct gnet_stats_rate_est64 *rate_est);
 int gen_replace_estimator(struct gnet_stats_basic_packed *bstats,
                          struct gnet_stats_basic_cpu __percpu *cpu_bstats,
                          struct gnet_stats_rate_est64 *rate_est,
                          spinlock_t *stats_lock,
-                         seqcount_t *running, struct nlattr *opt);
+                         net_seqlock_t *running, struct nlattr *opt);
 bool gen_estimator_active(const struct gnet_stats_basic_packed *bstats,
                          const struct gnet_stats_rate_est64 *rate_est);
 #endif
index a68a460..96a9308 100644 (file)
@@ -446,7 +446,7 @@ static inline int neigh_hh_bridge(struct hh_cache *hh, struct sk_buff *skb)
 }
 #endif
 
-static inline int neigh_hh_output(const struct hh_cache *hh, struct sk_buff *skb)
+static inline int neigh_hh_output(struct hh_cache *hh, struct sk_buff *skb)
 {
        unsigned int hh_alen = 0;
        unsigned int seq;
@@ -519,7 +519,7 @@ struct neighbour_cb {
 
 #define NEIGH_CB(skb)  ((struct neighbour_cb *)(skb)->cb)
 
-static inline void neigh_ha_snapshot(char *dst, const struct neighbour *n,
+static inline void neigh_ha_snapshot(char *dst, struct neighbour *n,
                                     const struct net_device *dev)
 {
        unsigned int seq;
diff --git a/include/net/net_seq_lock.h b/include/net/net_seq_lock.h
new file mode 100644 (file)
index 0000000..a703429
--- /dev/null
@@ -0,0 +1,15 @@
+#ifndef __NET_NET_SEQ_LOCK_H__
+#define __NET_NET_SEQ_LOCK_H__
+
+#ifdef CONFIG_PREEMPT_RT_BASE
+# define net_seqlock_t                 seqlock_t
+# define net_seq_begin(__r)            read_seqbegin(__r)
+# define net_seq_retry(__r, __s)       read_seqretry(__r, __s)
+
+#else
+# define net_seqlock_t                 seqcount_t
+# define net_seq_begin(__r)            read_seqcount_begin(__r)
+# define net_seq_retry(__r, __s)       read_seqcount_retry(__r, __s)
+#endif
+
+#endif
index af1c5e7..faf4a8c 100644 (file)
@@ -70,6 +70,7 @@ struct netns_ipv4 {
 
        int sysctl_icmp_echo_ignore_all;
        int sysctl_icmp_echo_ignore_broadcasts;
+       int sysctl_icmp_echo_sysrq;
        int sysctl_icmp_ignore_bogus_error_responses;
        int sysctl_icmp_ratelimit;
        int sysctl_icmp_ratemask;
index 5d5a137..3a6860f 100644 (file)
@@ -10,6 +10,7 @@
 #include <linux/dynamic_queue_limits.h>
 #include <net/gen_stats.h>
 #include <net/rtnetlink.h>
+#include <net/net_seq_lock.h>
 
 struct Qdisc_ops;
 struct qdisc_walker;
@@ -86,7 +87,7 @@ struct Qdisc {
        struct sk_buff          *gso_skb ____cacheline_aligned_in_smp;
        struct qdisc_skb_head   q;
        struct gnet_stats_basic_packed bstats;
-       seqcount_t              running;
+       net_seqlock_t           running;
        struct gnet_stats_queue qstats;
        unsigned long           state;
        struct Qdisc            *next_sched;
@@ -98,13 +99,22 @@ struct Qdisc {
        spinlock_t              busylock ____cacheline_aligned_in_smp;
 };
 
-static inline bool qdisc_is_running(const struct Qdisc *qdisc)
+static inline bool qdisc_is_running(struct Qdisc *qdisc)
 {
+#ifdef CONFIG_PREEMPT_RT_BASE
+       return spin_is_locked(&qdisc->running.lock) ? true : false;
+#else
        return (raw_read_seqcount(&qdisc->running) & 1) ? true : false;
+#endif
 }
 
 static inline bool qdisc_run_begin(struct Qdisc *qdisc)
 {
+#ifdef CONFIG_PREEMPT_RT_BASE
+       if (try_write_seqlock(&qdisc->running))
+               return true;
+       return false;
+#else
        if (qdisc_is_running(qdisc))
                return false;
        /* Variant of write_seqcount_begin() telling lockdep a trylock
@@ -113,11 +123,16 @@ static inline bool qdisc_run_begin(struct Qdisc *qdisc)
        raw_write_seqcount_begin(&qdisc->running);
        seqcount_acquire(&qdisc->running.dep_map, 0, 1, _RET_IP_);
        return true;
+#endif
 }
 
 static inline void qdisc_run_end(struct Qdisc *qdisc)
 {
+#ifdef CONFIG_PREEMPT_RT_BASE
+       write_sequnlock(&qdisc->running);
+#else
        write_seqcount_end(&qdisc->running);
+#endif
 }
 
 static inline bool qdisc_may_bulk(const struct Qdisc *qdisc)
@@ -313,7 +328,7 @@ static inline spinlock_t *qdisc_root_sleeping_lock(const struct Qdisc *qdisc)
        return qdisc_lock(root);
 }
 
-static inline seqcount_t *qdisc_root_sleeping_running(const struct Qdisc *qdisc)
+static inline net_seqlock_t *qdisc_root_sleeping_running(const struct Qdisc *qdisc)
 {
        struct Qdisc *root = qdisc_root_sleeping(qdisc);
 
diff --git a/include/trace/events/hist.h b/include/trace/events/hist.h
new file mode 100644 (file)
index 0000000..f7710de
--- /dev/null
@@ -0,0 +1,73 @@
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM hist
+
+#if !defined(_TRACE_HIST_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_HIST_H
+
+#include "latency_hist.h"
+#include <linux/tracepoint.h>
+
+#if !defined(CONFIG_PREEMPT_OFF_HIST) && !defined(CONFIG_INTERRUPT_OFF_HIST)
+#define trace_preemptirqsoff_hist(a, b)
+#define trace_preemptirqsoff_hist_rcuidle(a, b)
+#else
+TRACE_EVENT(preemptirqsoff_hist,
+
+       TP_PROTO(int reason, int starthist),
+
+       TP_ARGS(reason, starthist),
+
+       TP_STRUCT__entry(
+               __field(int,    reason)
+               __field(int,    starthist)
+       ),
+
+       TP_fast_assign(
+               __entry->reason         = reason;
+               __entry->starthist      = starthist;
+       ),
+
+       TP_printk("reason=%s starthist=%s", getaction(__entry->reason),
+                 __entry->starthist ? "start" : "stop")
+);
+#endif
+
+#ifndef CONFIG_MISSED_TIMER_OFFSETS_HIST
+#define trace_hrtimer_interrupt(a, b, c, d)
+#else
+TRACE_EVENT(hrtimer_interrupt,
+
+       TP_PROTO(int cpu, long long offset, struct task_struct *curr,
+               struct task_struct *task),
+
+       TP_ARGS(cpu, offset, curr, task),
+
+       TP_STRUCT__entry(
+               __field(int,            cpu)
+               __field(long long,      offset)
+               __array(char,           ccomm,  TASK_COMM_LEN)
+               __field(int,            cprio)
+               __array(char,           tcomm,  TASK_COMM_LEN)
+               __field(int,            tprio)
+       ),
+
+       TP_fast_assign(
+               __entry->cpu    = cpu;
+               __entry->offset = offset;
+               memcpy(__entry->ccomm, curr->comm, TASK_COMM_LEN);
+               __entry->cprio  = curr->prio;
+               memcpy(__entry->tcomm, task != NULL ? task->comm : "<none>",
+                       task != NULL ? TASK_COMM_LEN : 7);
+               __entry->tprio  = task != NULL ? task->prio : -1;
+       ),
+
+       TP_printk("cpu=%d offset=%lld curr=%s[%d] thread=%s[%d]",
+               __entry->cpu, __entry->offset, __entry->ccomm,
+               __entry->cprio, __entry->tcomm, __entry->tprio)
+);
+#endif
+
+#endif /* _TRACE_HIST_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
diff --git a/include/trace/events/latency_hist.h b/include/trace/events/latency_hist.h
new file mode 100644 (file)
index 0000000..d3f2fbd
--- /dev/null
@@ -0,0 +1,29 @@
+#ifndef _LATENCY_HIST_H
+#define _LATENCY_HIST_H
+
+enum hist_action {
+       IRQS_ON,
+       PREEMPT_ON,
+       TRACE_STOP,
+       IRQS_OFF,
+       PREEMPT_OFF,
+       TRACE_START,
+};
+
+static char *actions[] = {
+       "IRQS_ON",
+       "PREEMPT_ON",
+       "TRACE_STOP",
+       "IRQS_OFF",
+       "PREEMPT_OFF",
+       "TRACE_START",
+};
+
+static inline char *getaction(int action)
+{
+       if (action >= 0 && action <= sizeof(actions)/sizeof(actions[0]))
+               return actions[action];
+       return "unknown";
+}
+
+#endif /* _LATENCY_HIST_H */
index efe4abd..17bfbd9 100644 (file)
@@ -70,7 +70,7 @@ DECLARE_EVENT_CLASS(sched_wakeup_template,
        TP_fast_assign(
                memcpy(__entry->comm, p->comm, TASK_COMM_LEN);
                __entry->pid            = p->pid;
-               __entry->prio           = p->prio;
+               __entry->prio           = p->prio; /* XXX SCHED_DEADLINE */
                __entry->success        = 1; /* rudiment, kill when possible */
                __entry->target_cpu     = task_cpu(p);
        ),
@@ -147,6 +147,7 @@ TRACE_EVENT(sched_switch,
                memcpy(__entry->prev_comm, prev->comm, TASK_COMM_LEN);
                __entry->next_pid       = next->pid;
                __entry->next_prio      = next->prio;
+               /* XXX SCHED_DEADLINE */
        ),
 
        TP_printk("prev_comm=%s prev_pid=%d prev_prio=%d prev_state=%s%s ==> next_comm=%s next_pid=%d next_prio=%d",
@@ -181,7 +182,7 @@ TRACE_EVENT(sched_migrate_task,
        TP_fast_assign(
                memcpy(__entry->comm, p->comm, TASK_COMM_LEN);
                __entry->pid            = p->pid;
-               __entry->prio           = p->prio;
+               __entry->prio           = p->prio; /* XXX SCHED_DEADLINE */
                __entry->orig_cpu       = task_cpu(p);
                __entry->dest_cpu       = dest_cpu;
        ),
@@ -206,7 +207,7 @@ DECLARE_EVENT_CLASS(sched_process_template,
        TP_fast_assign(
                memcpy(__entry->comm, p->comm, TASK_COMM_LEN);
                __entry->pid            = p->pid;
-               __entry->prio           = p->prio;
+               __entry->prio           = p->prio; /* XXX SCHED_DEADLINE */
        ),
 
        TP_printk("comm=%s pid=%d prio=%d",
@@ -253,7 +254,7 @@ TRACE_EVENT(sched_process_wait,
        TP_fast_assign(
                memcpy(__entry->comm, current->comm, TASK_COMM_LEN);
                __entry->pid            = pid_nr(pid);
-               __entry->prio           = current->prio;
+               __entry->prio           = current->prio; /* XXX SCHED_DEADLINE */
        ),
 
        TP_printk("comm=%s pid=%d prio=%d",
@@ -437,9 +438,9 @@ DEFINE_EVENT(sched_stat_runtime, sched_stat_runtime,
  */
 TRACE_EVENT(sched_pi_setprio,
 
-       TP_PROTO(struct task_struct *tsk, int newprio),
+       TP_PROTO(struct task_struct *tsk, struct task_struct *pi_task),
 
-       TP_ARGS(tsk, newprio),
+       TP_ARGS(tsk, pi_task),
 
        TP_STRUCT__entry(
                __array( char,  comm,   TASK_COMM_LEN   )
@@ -452,7 +453,10 @@ TRACE_EVENT(sched_pi_setprio,
                memcpy(__entry->comm, tsk->comm, TASK_COMM_LEN);
                __entry->pid            = tsk->pid;
                __entry->oldprio        = tsk->prio;
-               __entry->newprio        = newprio;
+               __entry->newprio        = pi_task ?
+                               min(tsk->normal_prio, pi_task->prio) :
+                               tsk->normal_prio;
+               /* XXX SCHED_DEADLINE bits missing */
        ),
 
        TP_printk("comm=%s pid=%d oldprio=%d newprio=%d",
index ead5f45..01b79f6 100644 (file)
@@ -515,7 +515,7 @@ config TINY_RCU
 
 config RCU_EXPERT
        bool "Make expert-level adjustments to RCU configuration"
-       default n
+       default y if PREEMPT_RT_FULL
        help
          This option needs to be enabled if you wish to make
          expert-level adjustments to RCU configuration.  By default,
@@ -632,7 +632,7 @@ config RCU_FANOUT_LEAF
 
 config RCU_FAST_NO_HZ
        bool "Accelerate last non-dyntick-idle CPU's grace periods"
-       depends on NO_HZ_COMMON && SMP && RCU_EXPERT
+       depends on NO_HZ_COMMON && SMP && RCU_EXPERT && !PREEMPT_RT_FULL
        default n
        help
          This option permits CPUs to enter dynticks-idle state even if
@@ -659,7 +659,7 @@ config TREE_RCU_TRACE
 config RCU_BOOST
        bool "Enable RCU priority boosting"
        depends on RT_MUTEXES && PREEMPT_RCU && RCU_EXPERT
-       default n
+       default y if PREEMPT_RT_FULL
        help
          This option boosts the priority of preempted RCU readers that
          block the current preemptible RCU grace period for too long.
@@ -790,19 +790,6 @@ config RCU_NOCB_CPU_ALL
 
 endchoice
 
-config RCU_EXPEDITE_BOOT
-       bool
-       default n
-       help
-         This option enables expedited grace periods at boot time,
-         as if rcu_expedite_gp() had been invoked early in boot.
-         The corresponding rcu_unexpedite_gp() is invoked from
-         rcu_end_inkernel_boot(), which is intended to be invoked
-         at the end of the kernel-only boot sequence, just before
-         init is exec'ed.
-
-         Accept the default if unsure.
-
 endmenu # "RCU Subsystem"
 
 config BUILD_BIN2C
@@ -1149,6 +1136,7 @@ config CFS_BANDWIDTH
 config RT_GROUP_SCHED
        bool "Group scheduling for SCHED_RR/FIFO"
        depends on CGROUP_SCHED
+       depends on !PREEMPT_RT_FULL
        default n
        help
          This feature lets you explicitly allocate real CPU bandwidth
@@ -1918,6 +1906,7 @@ choice
 
 config SLAB
        bool "SLAB"
+       depends on !PREEMPT_RT_FULL
        select HAVE_HARDENED_USERCOPY_ALLOCATOR
        help
          The regular slab allocator that is established and known to work
@@ -1938,6 +1927,7 @@ config SLUB
 config SLOB
        depends on EXPERT
        bool "SLOB (Simple Allocator)"
+       depends on !PREEMPT_RT_FULL
        help
           SLOB replaces the stock allocator with a drastically simpler
           allocator. SLOB is generally more space efficient but
@@ -1956,7 +1946,7 @@ config SLAB_FREELIST_RANDOM
 
 config SLUB_CPU_PARTIAL
        default y
-       depends on SLUB && SMP
+       depends on SLUB && SMP && !PREEMPT_RT_FULL
        bool "SLUB per cpu partial cache"
        help
          Per cpu partial caches accellerate objects allocation and freeing
index d210b23..f646247 100644 (file)
@@ -33,4 +33,4 @@ silent_chk_compile.h = :
 include/generated/compile.h: FORCE
        @$($(quiet)chk_compile.h)
        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkcompile_h $@ \
-       "$(UTS_MACHINE)" "$(CONFIG_SMP)" "$(CONFIG_PREEMPT)" "$(CC) $(KBUILD_CFLAGS)"
+       "$(UTS_MACHINE)" "$(CONFIG_SMP)" "$(CONFIG_PREEMPT)" "$(CONFIG_PREEMPT_RT_FULL)" "$(CC) $(KBUILD_CFLAGS)"
index 8ed9fb3..e067af8 100644 (file)
@@ -516,6 +516,7 @@ asmlinkage __visible void __init start_kernel(void)
        setup_command_line(command_line);
        setup_nr_cpu_ids();
        setup_per_cpu_areas();
+       softirq_early_init();
        smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */
        boot_cpu_hotplug_init();
 
index 5cd9d80..c987efc 100644 (file)
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -712,6 +712,13 @@ undo:
 static void wake_up_sem_queue_prepare(struct list_head *pt,
                                struct sem_queue *q, int error)
 {
+#ifdef CONFIG_PREEMPT_RT_BASE
+       struct task_struct *p = q->sleeper;
+       get_task_struct(p);
+       q->status = error;
+       wake_up_process(p);
+       put_task_struct(p);
+#else
        if (list_empty(pt)) {
                /*
                 * Hold preempt off so that we don't get preempted and have the
@@ -723,6 +730,7 @@ static void wake_up_sem_queue_prepare(struct list_head *pt,
        q->pid = error;
 
        list_add_tail(&q->list, pt);
+#endif
 }
 
 /**
@@ -736,6 +744,7 @@ static void wake_up_sem_queue_prepare(struct list_head *pt,
  */
 static void wake_up_sem_queue_do(struct list_head *pt)
 {
+#ifndef CONFIG_PREEMPT_RT_BASE
        struct sem_queue *q, *t;
        int did_something;
 
@@ -748,6 +757,7 @@ static void wake_up_sem_queue_do(struct list_head *pt)
        }
        if (did_something)
                preempt_enable();
+#endif
 }
 
 static void unlink_queue(struct sem_array *sma, struct sem_queue *q)
index ebdb004..b9e6aa7 100644 (file)
@@ -225,11 +225,11 @@ config ARCH_SUPPORTS_ATOMIC_RMW
 
 config MUTEX_SPIN_ON_OWNER
        def_bool y
-       depends on SMP && !DEBUG_MUTEXES && ARCH_SUPPORTS_ATOMIC_RMW
+       depends on SMP && !DEBUG_MUTEXES && ARCH_SUPPORTS_ATOMIC_RMW && !PREEMPT_RT_FULL
 
 config RWSEM_SPIN_ON_OWNER
        def_bool y
-       depends on SMP && RWSEM_XCHGADD_ALGORITHM && ARCH_SUPPORTS_ATOMIC_RMW
+       depends on SMP && RWSEM_XCHGADD_ALGORITHM && ARCH_SUPPORTS_ATOMIC_RMW && !PREEMPT_RT_FULL
 
 config LOCK_SPIN_ON_OWNER
        def_bool y
index 3f9c974..11dbe26 100644 (file)
@@ -1,3 +1,16 @@
+config PREEMPT
+       bool
+       select PREEMPT_COUNT
+
+config PREEMPT_RT_BASE
+       bool
+       select PREEMPT
+
+config HAVE_PREEMPT_LAZY
+       bool
+
+config PREEMPT_LAZY
+       def_bool y if HAVE_PREEMPT_LAZY && PREEMPT_RT_FULL
 
 choice
        prompt "Preemption Model"
@@ -33,9 +46,9 @@ config PREEMPT_VOLUNTARY
 
          Select this if you are building a kernel for a desktop system.
 
-config PREEMPT
+config PREEMPT__LL
        bool "Preemptible Kernel (Low-Latency Desktop)"
-       select PREEMPT_COUNT
+       select PREEMPT
        select UNINLINE_SPIN_UNLOCK if !ARCH_INLINE_SPIN_UNLOCK
        help
          This option reduces the latency of the kernel by making
@@ -52,6 +65,22 @@ config PREEMPT
          embedded system with latency requirements in the milliseconds
          range.
 
+config PREEMPT_RTB
+       bool "Preemptible Kernel (Basic RT)"
+       select PREEMPT_RT_BASE
+       help
+         This option is basically the same as (Low-Latency Desktop) but
+         enables changes which are preliminary for the full preemptible
+         RT kernel.
+
+config PREEMPT_RT_FULL
+       bool "Fully Preemptible Kernel (RT)"
+       depends on IRQ_FORCED_THREADING
+       select PREEMPT_RT_BASE
+       select PREEMPT_RCU
+       help
+         All and everything
+
 endchoice
 
 config PREEMPT_COUNT
index 4b07e73..0b26108 100644 (file)
@@ -5046,10 +5046,10 @@ static void css_free_rcu_fn(struct rcu_head *rcu_head)
        queue_work(cgroup_destroy_wq, &css->destroy_work);
 }
 
-static void css_release_work_fn(struct work_struct *work)
+static void css_release_work_fn(struct swork_event *sev)
 {
        struct cgroup_subsys_state *css =
-               container_of(work, struct cgroup_subsys_state, destroy_work);
+               container_of(sev, struct cgroup_subsys_state, destroy_swork);
        struct cgroup_subsys *ss = css->ss;
        struct cgroup *cgrp = css->cgroup;
 
@@ -5094,8 +5094,8 @@ static void css_release(struct percpu_ref *ref)
        struct cgroup_subsys_state *css =
                container_of(ref, struct cgroup_subsys_state, refcnt);
 
-       INIT_WORK(&css->destroy_work, css_release_work_fn);
-       queue_work(cgroup_destroy_wq, &css->destroy_work);
+       INIT_SWORK(&css->destroy_swork, css_release_work_fn);
+       swork_queue(&css->destroy_swork);
 }
 
 static void init_and_link_css(struct cgroup_subsys_state *css,
@@ -5759,6 +5759,7 @@ static int __init cgroup_wq_init(void)
         */
        cgroup_destroy_wq = alloc_workqueue("cgroup_destroy", 0, 1);
        BUG_ON(!cgroup_destroy_wq);
+       BUG_ON(swork_get());
 
        /*
         * Used to destroy pidlists and separate to serve as flush domain.
index e55ed66..4ba72f3 100644 (file)
@@ -247,6 +247,289 @@ static struct {
 #define cpuhp_lock_acquire()      lock_map_acquire(&cpu_hotplug.dep_map)
 #define cpuhp_lock_release()      lock_map_release(&cpu_hotplug.dep_map)
 
+/**
+ * hotplug_pcp - per cpu hotplug descriptor
+ * @unplug:    set when pin_current_cpu() needs to sync tasks
+ * @sync_tsk:  the task that waits for tasks to finish pinned sections
+ * @refcount:  counter of tasks in pinned sections
+ * @grab_lock: set when the tasks entering pinned sections should wait
+ * @synced:    notifier for @sync_tsk to tell cpu_down it's finished
+ * @mutex:     the mutex to make tasks wait (used when @grab_lock is true)
+ * @mutex_init:        zero if the mutex hasn't been initialized yet.
+ *
+ * Although @unplug and @sync_tsk may point to the same task, the @unplug
+ * is used as a flag and still exists after @sync_tsk has exited and
+ * @sync_tsk set to NULL.
+ */
+struct hotplug_pcp {
+       struct task_struct *unplug;
+       struct task_struct *sync_tsk;
+       int refcount;
+       int grab_lock;
+       struct completion synced;
+       struct completion unplug_wait;
+#ifdef CONFIG_PREEMPT_RT_FULL
+       /*
+        * Note, on PREEMPT_RT, the hotplug lock must save the state of
+        * the task, otherwise the mutex will cause the task to fail
+        * to sleep when required. (Because it's called from migrate_disable())
+        *
+        * The spinlock_t on PREEMPT_RT is a mutex that saves the task's
+        * state.
+        */
+       spinlock_t lock;
+#else
+       struct mutex mutex;
+#endif
+       int mutex_init;
+};
+
+#ifdef CONFIG_PREEMPT_RT_FULL
+# define hotplug_lock(hp) rt_spin_lock__no_mg(&(hp)->lock)
+# define hotplug_unlock(hp) rt_spin_unlock__no_mg(&(hp)->lock)
+#else
+# define hotplug_lock(hp) mutex_lock(&(hp)->mutex)
+# define hotplug_unlock(hp) mutex_unlock(&(hp)->mutex)
+#endif
+
+static DEFINE_PER_CPU(struct hotplug_pcp, hotplug_pcp);
+
+/**
+ * pin_current_cpu - Prevent the current cpu from being unplugged
+ *
+ * Lightweight version of get_online_cpus() to prevent cpu from being
+ * unplugged when code runs in a migration disabled region.
+ *
+ * Must be called with preemption disabled (preempt_count = 1)!
+ */
+void pin_current_cpu(void)
+{
+       struct hotplug_pcp *hp;
+       int force = 0;
+
+retry:
+       hp = this_cpu_ptr(&hotplug_pcp);
+
+       if (!hp->unplug || hp->refcount || force || preempt_count() > 1 ||
+           hp->unplug == current) {
+               hp->refcount++;
+               return;
+       }
+       if (hp->grab_lock) {
+               preempt_enable();
+               hotplug_lock(hp);
+               hotplug_unlock(hp);
+       } else {
+               preempt_enable();
+               /*
+                * Try to push this task off of this CPU.
+                */
+               if (!migrate_me()) {
+                       preempt_disable();
+                       hp = this_cpu_ptr(&hotplug_pcp);
+                       if (!hp->grab_lock) {
+                               /*
+                                * Just let it continue it's already pinned
+                                * or about to sleep.
+                                */
+                               force = 1;
+                               goto retry;
+                       }
+                       preempt_enable();
+               }
+       }
+       preempt_disable();
+       goto retry;
+}
+
+/**
+ * unpin_current_cpu - Allow unplug of current cpu
+ *
+ * Must be called with preemption or interrupts disabled!
+ */
+void unpin_current_cpu(void)
+{
+       struct hotplug_pcp *hp = this_cpu_ptr(&hotplug_pcp);
+
+       WARN_ON(hp->refcount <= 0);
+
+       /* This is safe. sync_unplug_thread is pinned to this cpu */
+       if (!--hp->refcount && hp->unplug && hp->unplug != current)
+               wake_up_process(hp->unplug);
+}
+
+static void wait_for_pinned_cpus(struct hotplug_pcp *hp)
+{
+       set_current_state(TASK_UNINTERRUPTIBLE);
+       while (hp->refcount) {
+               schedule_preempt_disabled();
+               set_current_state(TASK_UNINTERRUPTIBLE);
+       }
+}
+
+static int sync_unplug_thread(void *data)
+{
+       struct hotplug_pcp *hp = data;
+
+       wait_for_completion(&hp->unplug_wait);
+       preempt_disable();
+       hp->unplug = current;
+       wait_for_pinned_cpus(hp);
+
+       /*
+        * This thread will synchronize the cpu_down() with threads
+        * that have pinned the CPU. When the pinned CPU count reaches
+        * zero, we inform the cpu_down code to continue to the next step.
+        */
+       set_current_state(TASK_UNINTERRUPTIBLE);
+       preempt_enable();
+       complete(&hp->synced);
+
+       /*
+        * If all succeeds, the next step will need tasks to wait till
+        * the CPU is offline before continuing. To do this, the grab_lock
+        * is set and tasks going into pin_current_cpu() will block on the
+        * mutex. But we still need to wait for those that are already in
+        * pinned CPU sections. If the cpu_down() failed, the kthread_should_stop()
+        * will kick this thread out.
+        */
+       while (!hp->grab_lock && !kthread_should_stop()) {
+               schedule();
+               set_current_state(TASK_UNINTERRUPTIBLE);
+       }
+
+       /* Make sure grab_lock is seen before we see a stale completion */
+       smp_mb();
+
+       /*
+        * Now just before cpu_down() enters stop machine, we need to make
+        * sure all tasks that are in pinned CPU sections are out, and new
+        * tasks will now grab the lock, keeping them from entering pinned
+        * CPU sections.
+        */
+       if (!kthread_should_stop()) {
+               preempt_disable();
+               wait_for_pinned_cpus(hp);
+               preempt_enable();
+               complete(&hp->synced);
+       }
+
+       set_current_state(TASK_UNINTERRUPTIBLE);
+       while (!kthread_should_stop()) {
+               schedule();
+               set_current_state(TASK_UNINTERRUPTIBLE);
+       }
+       set_current_state(TASK_RUNNING);
+
+       /*
+        * Force this thread off this CPU as it's going down and
+        * we don't want any more work on this CPU.
+        */
+       current->flags &= ~PF_NO_SETAFFINITY;
+       set_cpus_allowed_ptr(current, cpu_present_mask);
+       migrate_me();
+       return 0;
+}
+
+static void __cpu_unplug_sync(struct hotplug_pcp *hp)
+{
+       wake_up_process(hp->sync_tsk);
+       wait_for_completion(&hp->synced);
+}
+
+static void __cpu_unplug_wait(unsigned int cpu)
+{
+       struct hotplug_pcp *hp = &per_cpu(hotplug_pcp, cpu);
+
+       complete(&hp->unplug_wait);
+       wait_for_completion(&hp->synced);
+}
+
+/*
+ * Start the sync_unplug_thread on the target cpu and wait for it to
+ * complete.
+ */
+static int cpu_unplug_begin(unsigned int cpu)
+{
+       struct hotplug_pcp *hp = &per_cpu(hotplug_pcp, cpu);
+       int err;
+
+       /* Protected by cpu_hotplug.lock */
+       if (!hp->mutex_init) {
+#ifdef CONFIG_PREEMPT_RT_FULL
+               spin_lock_init(&hp->lock);
+#else
+               mutex_init(&hp->mutex);
+#endif
+               hp->mutex_init = 1;
+       }
+
+       /* Inform the scheduler to migrate tasks off this CPU */
+       tell_sched_cpu_down_begin(cpu);
+
+       init_completion(&hp->synced);
+       init_completion(&hp->unplug_wait);
+
+       hp->sync_tsk = kthread_create(sync_unplug_thread, hp, "sync_unplug/%d", cpu);
+       if (IS_ERR(hp->sync_tsk)) {
+               err = PTR_ERR(hp->sync_tsk);
+               hp->sync_tsk = NULL;
+               return err;
+       }
+       kthread_bind(hp->sync_tsk, cpu);
+
+       /*
+        * Wait for tasks to get out of the pinned sections,
+        * it's still OK if new tasks enter. Some CPU notifiers will
+        * wait for tasks that are going to enter these sections and
+        * we must not have them block.
+        */
+       wake_up_process(hp->sync_tsk);
+       return 0;
+}
+
+static void cpu_unplug_sync(unsigned int cpu)
+{
+       struct hotplug_pcp *hp = &per_cpu(hotplug_pcp, cpu);
+
+       init_completion(&hp->synced);
+       /* The completion needs to be initialzied before setting grab_lock */
+       smp_wmb();
+
+       /* Grab the mutex before setting grab_lock */
+       hotplug_lock(hp);
+       hp->grab_lock = 1;
+
+       /*
+        * The CPU notifiers have been completed.
+        * Wait for tasks to get out of pinned CPU sections and have new
+        * tasks block until the CPU is completely down.
+        */
+       __cpu_unplug_sync(hp);
+
+       /* All done with the sync thread */
+       kthread_stop(hp->sync_tsk);
+       hp->sync_tsk = NULL;
+}
+
+static void cpu_unplug_done(unsigned int cpu)
+{
+       struct hotplug_pcp *hp = &per_cpu(hotplug_pcp, cpu);
+
+       hp->unplug = NULL;
+       /* Let all tasks know cpu unplug is finished before cleaning up */
+       smp_wmb();
+
+       if (hp->sync_tsk)
+               kthread_stop(hp->sync_tsk);
+
+       if (hp->grab_lock) {
+               hotplug_unlock(hp);
+               /* protected by cpu_hotplug.lock */
+               hp->grab_lock = 0;
+       }
+       tell_sched_cpu_down_done(cpu);
+}
 
 void get_online_cpus(void)
 {
@@ -928,9 +1211,13 @@ static int takedown_cpu(unsigned int cpu)
        struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu);
        int err;
 
+       __cpu_unplug_wait(cpu);
        /* Park the smpboot threads */
        kthread_park(per_cpu_ptr(&cpuhp_state, cpu)->thread);
 
+       /* Notifiers are done. Don't let any more tasks pin this CPU. */
+       cpu_unplug_sync(cpu);
+
        /*
         * Prevent irq alloc/free while the dying cpu reorganizes the
         * interrupt affinities.
@@ -1015,6 +1302,9 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen,
        struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu);
        int prev_state, ret = 0;
        bool hasdied = false;
+       int mycpu;
+       cpumask_var_t cpumask;
+       cpumask_var_t cpumask_org;
 
        if (num_online_cpus() == 1)
                return -EBUSY;
@@ -1022,7 +1312,34 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen,
        if (!cpu_present(cpu))
                return -EINVAL;
 
+       /* Move the downtaker off the unplug cpu */
+       if (!alloc_cpumask_var(&cpumask, GFP_KERNEL))
+               return -ENOMEM;
+       if (!alloc_cpumask_var(&cpumask_org, GFP_KERNEL))  {
+               free_cpumask_var(cpumask);
+               return -ENOMEM;
+       }
+
+       cpumask_copy(cpumask_org, tsk_cpus_allowed(current));
+       cpumask_andnot(cpumask, cpu_online_mask, cpumask_of(cpu));
+       set_cpus_allowed_ptr(current, cpumask);
+       free_cpumask_var(cpumask);
+       migrate_disable();
+       mycpu = smp_processor_id();
+       if (mycpu == cpu) {
+               printk(KERN_ERR "Yuck! Still on unplug CPU\n!");
+               migrate_enable();
+               ret = -EBUSY;
+               goto restore_cpus;
+       }
+
+       migrate_enable();
        cpu_hotplug_begin();
+       ret = cpu_unplug_begin(cpu);
+       if (ret) {
+               printk("cpu_unplug_begin(%d) failed\n", cpu);
+               goto out_cancel;
+       }
 
        cpuhp_tasks_frozen = tasks_frozen;
 
@@ -1061,10 +1378,15 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen,
 
        hasdied = prev_state != st->state && st->state == CPUHP_OFFLINE;
 out:
+       cpu_unplug_done(cpu);
+out_cancel:
        cpu_hotplug_done();
        /* This post dead nonsense must die */
        if (!ret && hasdied)
                cpu_notify_nofail(CPU_POST_DEAD, cpu);
+restore_cpus:
+       set_cpus_allowed_ptr(current, cpumask_org);
+       free_cpumask_var(cpumask_org);
        arch_smt_update();
        return ret;
 }
@@ -1386,6 +1708,8 @@ core_initcall(cpu_hotplug_pm_sync_init);
 
 #endif /* CONFIG_PM_SLEEP_SMP */
 
+int __boot_cpu_id;
+
 #endif /* CONFIG_SMP */
 
 /* Boot processor state steps */
@@ -2232,6 +2556,10 @@ void __init boot_cpu_init(void)
        set_cpu_active(cpu, true);
        set_cpu_present(cpu, true);
        set_cpu_possible(cpu, true);
+
+#ifdef CONFIG_SMP
+       __boot_cpu_id = cpu;
+#endif
 }
 
 /*
index f1042d6..2ed6351 100644 (file)
 #include <linux/spinlock.h>
 #include <linux/syscore_ops.h>
 
-static DEFINE_RWLOCK(cpu_pm_notifier_lock);
-static RAW_NOTIFIER_HEAD(cpu_pm_notifier_chain);
+static ATOMIC_NOTIFIER_HEAD(cpu_pm_notifier_chain);
 
 static int cpu_pm_notify(enum cpu_pm_event event, int nr_to_call, int *nr_calls)
 {
        int ret;
 
-       ret = __raw_notifier_call_chain(&cpu_pm_notifier_chain, event, NULL,
+       /*
+        * __atomic_notifier_call_chain has a RCU read critical section, which
+        * could be disfunctional in cpu idle. Copy RCU_NONIDLE code to let
+        * RCU know this.
+        */
+       rcu_irq_enter_irqson();
+       ret = __atomic_notifier_call_chain(&cpu_pm_notifier_chain, event, NULL,
                nr_to_call, nr_calls);
+       rcu_irq_exit_irqson();
 
        return notifier_to_errno(ret);
 }
@@ -47,14 +53,7 @@ static int cpu_pm_notify(enum cpu_pm_event event, int nr_to_call, int *nr_calls)
  */
 int cpu_pm_register_notifier(struct notifier_block *nb)
 {
-       unsigned long flags;
-       int ret;
-
-       write_lock_irqsave(&cpu_pm_notifier_lock, flags);
-       ret = raw_notifier_chain_register(&cpu_pm_notifier_chain, nb);
-       write_unlock_irqrestore(&cpu_pm_notifier_lock, flags);
-
-       return ret;
+       return atomic_notifier_chain_register(&cpu_pm_notifier_chain, nb);
 }
 EXPORT_SYMBOL_GPL(cpu_pm_register_notifier);
 
@@ -69,14 +68,7 @@ EXPORT_SYMBOL_GPL(cpu_pm_register_notifier);
  */
 int cpu_pm_unregister_notifier(struct notifier_block *nb)
 {
-       unsigned long flags;
-       int ret;
-
-       write_lock_irqsave(&cpu_pm_notifier_lock, flags);
-       ret = raw_notifier_chain_unregister(&cpu_pm_notifier_chain, nb);
-       write_unlock_irqrestore(&cpu_pm_notifier_lock, flags);
-
-       return ret;
+       return atomic_notifier_chain_unregister(&cpu_pm_notifier_chain, nb);
 }
 EXPORT_SYMBOL_GPL(cpu_pm_unregister_notifier);
 
@@ -100,7 +92,6 @@ int cpu_pm_enter(void)
        int nr_calls = 0;
        int ret = 0;
 
-       read_lock(&cpu_pm_notifier_lock);
        ret = cpu_pm_notify(CPU_PM_ENTER, -1, &nr_calls);
        if (ret)
                /*
@@ -108,7 +99,6 @@ int cpu_pm_enter(void)
                 * PM entry who are notified earlier to prepare for it.
                 */
                cpu_pm_notify(CPU_PM_ENTER_FAILED, nr_calls - 1, NULL);
-       read_unlock(&cpu_pm_notifier_lock);
 
        return ret;
 }
@@ -128,13 +118,7 @@ EXPORT_SYMBOL_GPL(cpu_pm_enter);
  */
 int cpu_pm_exit(void)
 {
-       int ret;
-
-       read_lock(&cpu_pm_notifier_lock);
-       ret = cpu_pm_notify(CPU_PM_EXIT, -1, NULL);
-       read_unlock(&cpu_pm_notifier_lock);
-
-       return ret;
+       return cpu_pm_notify(CPU_PM_EXIT, -1, NULL);
 }
 EXPORT_SYMBOL_GPL(cpu_pm_exit);
 
@@ -159,7 +143,6 @@ int cpu_cluster_pm_enter(void)
        int nr_calls = 0;
        int ret = 0;
 
-       read_lock(&cpu_pm_notifier_lock);
        ret = cpu_pm_notify(CPU_CLUSTER_PM_ENTER, -1, &nr_calls);
        if (ret)
                /*
@@ -167,7 +150,6 @@ int cpu_cluster_pm_enter(void)
                 * PM entry who are notified earlier to prepare for it.
                 */
                cpu_pm_notify(CPU_CLUSTER_PM_ENTER_FAILED, nr_calls - 1, NULL);
-       read_unlock(&cpu_pm_notifier_lock);
 
        return ret;
 }
@@ -190,13 +172,7 @@ EXPORT_SYMBOL_GPL(cpu_cluster_pm_enter);
  */
 int cpu_cluster_pm_exit(void)
 {
-       int ret;
-
-       read_lock(&cpu_pm_notifier_lock);
-       ret = cpu_pm_notify(CPU_CLUSTER_PM_EXIT, -1, NULL);
-       read_unlock(&cpu_pm_notifier_lock);
-
-       return ret;
+       return cpu_pm_notify(CPU_CLUSTER_PM_EXIT, -1, NULL);
 }
 EXPORT_SYMBOL_GPL(cpu_cluster_pm_exit);
 
index 194e2f2..0eb1411 100644 (file)
@@ -286,7 +286,7 @@ static struct cpuset top_cpuset = {
  */
 
 static DEFINE_MUTEX(cpuset_mutex);
-static DEFINE_SPINLOCK(callback_lock);
+static DEFINE_RAW_SPINLOCK(callback_lock);
 
 static struct workqueue_struct *cpuset_migrate_mm_wq;
 
@@ -909,9 +909,9 @@ static void update_cpumasks_hier(struct cpuset *cs, struct cpumask *new_cpus)
                        continue;
                rcu_read_unlock();
 
-               spin_lock_irq(&callback_lock);
+               raw_spin_lock_irq(&callback_lock);
                cpumask_copy(cp->effective_cpus, new_cpus);
-               spin_unlock_irq(&callback_lock);
+               raw_spin_unlock_irq(&callback_lock);
 
                WARN_ON(!cgroup_subsys_on_dfl(cpuset_cgrp_subsys) &&
                        !cpumask_equal(cp->cpus_allowed, cp->effective_cpus));
@@ -977,10 +977,10 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs,
        if (retval < 0)
                return retval;
 
-       spin_lock_irq(&callback_lock);
+       raw_spin_lock_irq(&callback_lock);
        cpumask_copy(cs->cpus_allowed, trialcs->cpus_allowed);
        cpumask_copy(cs->cpus_requested, trialcs->cpus_requested);
-       spin_unlock_irq(&callback_lock);
+       raw_spin_unlock_irq(&callback_lock);
 
        /* use trialcs->cpus_allowed as a temp variable */
        update_cpumasks_hier(cs, trialcs->cpus_allowed);
@@ -1180,9 +1180,9 @@ static void update_nodemasks_hier(struct cpuset *cs, nodemask_t *new_mems)
                        continue;
                rcu_read_unlock();
 
-               spin_lock_irq(&callback_lock);
+               raw_spin_lock_irq(&callback_lock);
                cp->effective_mems = *new_mems;
-               spin_unlock_irq(&callback_lock);
+               raw_spin_unlock_irq(&callback_lock);
 
                WARN_ON(!cgroup_subsys_on_dfl(cpuset_cgrp_subsys) &&
                        !nodes_equal(cp->mems_allowed, cp->effective_mems));
@@ -1250,9 +1250,9 @@ static int update_nodemask(struct cpuset *cs, struct cpuset *trialcs,
        if (retval < 0)
                goto done;
 
-       spin_lock_irq(&callback_lock);
+       raw_spin_lock_irq(&callback_lock);
        cs->mems_allowed = trialcs->mems_allowed;
-       spin_unlock_irq(&callback_lock);
+       raw_spin_unlock_irq(&callback_lock);
 
        /* use trialcs->mems_allowed as a temp variable */
        update_nodemasks_hier(cs, &trialcs->mems_allowed);
@@ -1343,9 +1343,9 @@ static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs,
        spread_flag_changed = ((is_spread_slab(cs) != is_spread_slab(trialcs))
                        || (is_spread_page(cs) != is_spread_page(trialcs)));
 
-       spin_lock_irq(&callback_lock);
+       raw_spin_lock_irq(&callback_lock);
        cs->flags = trialcs->flags;
-       spin_unlock_irq(&callback_lock);
+       raw_spin_unlock_irq(&callback_lock);
 
        if (!cpumask_empty(trialcs->cpus_allowed) && balance_flag_changed)
                rebuild_sched_domains_locked();
@@ -1760,7 +1760,7 @@ static int cpuset_common_seq_show(struct seq_file *sf, void *v)
        cpuset_filetype_t type = seq_cft(sf)->private;
        int ret = 0;
 
-       spin_lock_irq(&callback_lock);
+       raw_spin_lock_irq(&callback_lock);
 
        switch (type) {
        case FILE_CPULIST:
@@ -1779,7 +1779,7 @@ static int cpuset_common_seq_show(struct seq_file *sf, void *v)
                ret = -EINVAL;
        }
 
-       spin_unlock_irq(&callback_lock);
+       raw_spin_unlock_irq(&callback_lock);
        return ret;
 }
 
@@ -1999,12 +1999,12 @@ static int cpuset_css_online(struct cgroup_subsys_state *css)
 
        cpuset_inc();
 
-       spin_lock_irq(&callback_lock);
+       raw_spin_lock_irq(&callback_lock);
        if (cgroup_subsys_on_dfl(cpuset_cgrp_subsys)) {
                cpumask_copy(cs->effective_cpus, parent->effective_cpus);
                cs->effective_mems = parent->effective_mems;
        }
-       spin_unlock_irq(&callback_lock);
+       raw_spin_unlock_irq(&callback_lock);
 
        if (!test_bit(CGRP_CPUSET_CLONE_CHILDREN, &css->cgroup->flags))
                goto out_unlock;
@@ -2031,13 +2031,13 @@ static int cpuset_css_online(struct cgroup_subsys_state *css)
        }
        rcu_read_unlock();
 
-       spin_lock_irq(&callback_lock);
+       raw_spin_lock_irq(&callback_lock);
        cs->mems_allowed = parent->mems_allowed;
        cs->effective_mems = parent->mems_allowed;
        cpumask_copy(cs->cpus_allowed, parent->cpus_allowed);
        cpumask_copy(cs->cpus_requested, parent->cpus_requested);
        cpumask_copy(cs->effective_cpus, parent->cpus_allowed);
-       spin_unlock_irq(&callback_lock);
+       raw_spin_unlock_irq(&callback_lock);
 out_unlock:
        mutex_unlock(&cpuset_mutex);
        return 0;
@@ -2077,7 +2077,7 @@ static void cpuset_css_free(struct cgroup_subsys_state *css)
 static void cpuset_bind(struct cgroup_subsys_state *root_css)
 {
        mutex_lock(&cpuset_mutex);
-       spin_lock_irq(&callback_lock);
+       raw_spin_lock_irq(&callback_lock);
 
        if (cgroup_subsys_on_dfl(cpuset_cgrp_subsys)) {
                cpumask_copy(top_cpuset.cpus_allowed, cpu_possible_mask);
@@ -2088,7 +2088,7 @@ static void cpuset_bind(struct cgroup_subsys_state *root_css)
                top_cpuset.mems_allowed = top_cpuset.effective_mems;
        }
 
-       spin_unlock_irq(&callback_lock);
+       raw_spin_unlock_irq(&callback_lock);
        mutex_unlock(&cpuset_mutex);
 }
 
@@ -2192,12 +2192,12 @@ hotplug_update_tasks_legacy(struct cpuset *cs,
 {
        bool is_empty;
 
-       spin_lock_irq(&callback_lock);
+       raw_spin_lock_irq(&callback_lock);
        cpumask_copy(cs->cpus_allowed, new_cpus);
        cpumask_copy(cs->effective_cpus, new_cpus);
        cs->mems_allowed = *new_mems;
        cs->effective_mems = *new_mems;
-       spin_unlock_irq(&callback_lock);
+       raw_spin_unlock_irq(&callback_lock);
 
        /*
         * Don't call update_tasks_cpumask() if the cpuset becomes empty,
@@ -2234,10 +2234,10 @@ hotplug_update_tasks(struct cpuset *cs,
        if (nodes_empty(*new_mems))
                *new_mems = parent_cs(cs)->effective_mems;
 
-       spin_lock_irq(&callback_lock);
+       raw_spin_lock_irq(&callback_lock);
        cpumask_copy(cs->effective_cpus, new_cpus);
        cs->effective_mems = *new_mems;
-       spin_unlock_irq(&callback_lock);
+       raw_spin_unlock_irq(&callback_lock);
 
        if (cpus_updated)
                update_tasks_cpumask(cs);
@@ -2330,21 +2330,21 @@ static void cpuset_hotplug_workfn(struct work_struct *work)
 
        /* synchronize cpus_allowed to cpu_active_mask */
        if (cpus_updated) {
-               spin_lock_irq(&callback_lock);
+               raw_spin_lock_irq(&callback_lock);
                if (!on_dfl)
                        cpumask_copy(top_cpuset.cpus_allowed, &new_cpus);
                cpumask_copy(top_cpuset.effective_cpus, &new_cpus);
-               spin_unlock_irq(&callback_lock);
+               raw_spin_unlock_irq(&callback_lock);
                /* we don't mess with cpumasks of tasks in top_cpuset */
        }
 
        /* synchronize mems_allowed to N_MEMORY */
        if (mems_updated) {
-               spin_lock_irq(&callback_lock);
+               raw_spin_lock_irq(&callback_lock);
                if (!on_dfl)
                        top_cpuset.mems_allowed = new_mems;
                top_cpuset.effective_mems = new_mems;
-               spin_unlock_irq(&callback_lock);
+               raw_spin_unlock_irq(&callback_lock);
                update_tasks_nodemask(&top_cpuset);
        }
 
@@ -2449,11 +2449,11 @@ void cpuset_cpus_allowed(struct task_struct *tsk, struct cpumask *pmask)
 {
        unsigned long flags;
 
-       spin_lock_irqsave(&callback_lock, flags);
+       raw_spin_lock_irqsave(&callback_lock, flags);
        rcu_read_lock();
        guarantee_online_cpus(task_cs(tsk), pmask);
        rcu_read_unlock();
-       spin_unlock_irqrestore(&callback_lock, flags);
+       raw_spin_unlock_irqrestore(&callback_lock, flags);
 }
 
 void cpuset_cpus_allowed_fallback(struct task_struct *tsk)
@@ -2501,11 +2501,11 @@ nodemask_t cpuset_mems_allowed(struct task_struct *tsk)
        nodemask_t mask;
        unsigned long flags;
 
-       spin_lock_irqsave(&callback_lock, flags);
+       raw_spin_lock_irqsave(&callback_lock, flags);
        rcu_read_lock();
        guarantee_online_mems(task_cs(tsk), &mask);
        rcu_read_unlock();
-       spin_unlock_irqrestore(&callback_lock, flags);
+       raw_spin_unlock_irqrestore(&callback_lock, flags);
 
        return mask;
 }
@@ -2597,14 +2597,14 @@ bool __cpuset_node_allowed(int node, gfp_t gfp_mask)
                return true;
 
        /* Not hardwall and node outside mems_allowed: scan up cpusets */
-       spin_lock_irqsave(&callback_lock, flags);
+       raw_spin_lock_irqsave(&callback_lock, flags);
 
        rcu_read_lock();
        cs = nearest_hardwall_ancestor(task_cs(current));
        allowed = node_isset(node, cs->mems_allowed);
        rcu_read_unlock();
 
-       spin_unlock_irqrestore(&callback_lock, flags);
+       raw_spin_unlock_irqrestore(&callback_lock, flags);
        return allowed;
 }
 
index bc7a833..e14c870 100644 (file)
@@ -565,7 +565,6 @@ int vkdb_printf(enum kdb_msgsrc src, const char *fmt, va_list ap)
        int linecount;
        int colcount;
        int logging, saved_loglevel = 0;
-       int saved_trap_printk;
        int got_printf_lock = 0;
        int retlen = 0;
        int fnd, len;
@@ -576,8 +575,6 @@ int vkdb_printf(enum kdb_msgsrc src, const char *fmt, va_list ap)
        unsigned long uninitialized_var(flags);
 
        preempt_disable();
-       saved_trap_printk = kdb_trap_printk;
-       kdb_trap_printk = 0;
 
        /* Serialize kdb_printf if multiple cpus try to write at once.
         * But if any cpu goes recursive in kdb, just print the output,
@@ -870,7 +867,6 @@ kdb_print_out:
        } else {
                __release(kdb_printf_lock);
        }
-       kdb_trap_printk = saved_trap_printk;
        preempt_enable();
        return retlen;
 }
@@ -880,9 +876,11 @@ int kdb_printf(const char *fmt, ...)
        va_list ap;
        int r;
 
+       kdb_trap_printk++;
        va_start(ap, fmt);
        r = vkdb_printf(KDB_MSGSRC_INTERNAL, fmt, ap);
        va_end(ap);
+       kdb_trap_printk--;
 
        return r;
 }
index 55454bf..d870051 100644 (file)
@@ -1072,6 +1072,7 @@ static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu)
        raw_spin_lock_init(&cpuctx->hrtimer_lock);
        hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED);
        timer->function = perf_mux_hrtimer_handler;
+       timer->irqsafe = 1;
 }
 
 static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx)
@@ -8474,6 +8475,7 @@ static void perf_swevent_init_hrtimer(struct perf_event *event)
 
        hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
        hwc->hrtimer.function = perf_swevent_hrtimer;
+       hwc->hrtimer.irqsafe = 1;
 
        /*
         * Since hrtimers have a fixed rate, we can do a static freq->period
index 0e20d12..330db90 100644 (file)
@@ -145,7 +145,7 @@ static void __exit_signal(struct task_struct *tsk)
         * Do this under ->siglock, we can race with another thread
         * doing sigqueue_free() if we have SIGQUEUE_PREALLOC signals.
         */
-       flush_sigqueue(&tsk->pending);
+       flush_task_sigqueue(tsk);
        tsk->sighand = NULL;
        spin_unlock(&sighand->siglock);
 
index f305d52..5250df3 100644 (file)
@@ -78,6 +78,7 @@
 #include <linux/sysctl.h>
 #include <linux/kcov.h>
 #include <linux/cpufreq_times.h>
+#include <linux/kprobes.h>
 
 #include <asm/pgtable.h>
 #include <asm/pgalloc.h>
@@ -400,13 +401,24 @@ static inline void put_signal_struct(struct signal_struct *sig)
        if (atomic_dec_and_test(&sig->sigcnt))
                free_signal_struct(sig);
 }
-
+#ifdef CONFIG_PREEMPT_RT_BASE
+static
+#endif
 void __put_task_struct(struct task_struct *tsk)
 {
        WARN_ON(!tsk->exit_state);
        WARN_ON(atomic_read(&tsk->usage));
        WARN_ON(tsk == current);
 
+       /*
+        * Remove function-return probe instances associated with this
+        * task and put them back on the free list.
+        */
+       kprobe_flush_task(tsk);
+
+       /* Task is done with its stack. */
+       put_task_stack(tsk);
+
        cgroup_free(tsk);
        task_numa_free(tsk, true);
        security_task_free(tsk);
@@ -417,7 +429,18 @@ void __put_task_struct(struct task_struct *tsk)
        if (!profile_handoff_task(tsk))
                free_task(tsk);
 }
+#ifndef CONFIG_PREEMPT_RT_BASE
 EXPORT_SYMBOL_GPL(__put_task_struct);
+#else
+void __put_task_struct_cb(struct rcu_head *rhp)
+{
+       struct task_struct *tsk = container_of(rhp, struct task_struct, put_rcu);
+
+       __put_task_struct(tsk);
+
+}
+EXPORT_SYMBOL_GPL(__put_task_struct_cb);
+#endif
 
 void __init __weak arch_task_cache_init(void) { }
 
@@ -565,6 +588,7 @@ static struct task_struct *dup_task_struct(struct task_struct *orig, int node)
        tsk->splice_pipe = NULL;
        tsk->task_frag.page = NULL;
        tsk->wake_q.next = NULL;
+       tsk->wake_q_sleeper.next = NULL;
 
        account_kernel_stack(tsk, 1);
 
@@ -891,6 +915,19 @@ void __mmdrop(struct mm_struct *mm)
 }
 EXPORT_SYMBOL_GPL(__mmdrop);
 
+#ifdef CONFIG_PREEMPT_RT_BASE
+/*
+ * RCU callback for delayed mm drop. Not strictly rcu, but we don't
+ * want another facility to make this work.
+ */
+void __mmdrop_delayed(struct rcu_head *rhp)
+{
+       struct mm_struct *mm = container_of(rhp, struct mm_struct, delayed_drop);
+
+       __mmdrop(mm);
+}
+#endif
+
 static inline void __mmput(struct mm_struct *mm)
 {
        VM_BUG_ON(atomic_read(&mm->mm_users));
@@ -1458,6 +1495,7 @@ static void rt_mutex_init_task(struct task_struct *p)
 #ifdef CONFIG_RT_MUTEXES
        p->pi_waiters = RB_ROOT;
        p->pi_waiters_leftmost = NULL;
+       p->pi_top_task = NULL;
        p->pi_blocked_on = NULL;
 #endif
 }
@@ -1467,6 +1505,9 @@ static void rt_mutex_init_task(struct task_struct *p)
  */
 static void posix_cpu_timers_init(struct task_struct *tsk)
 {
+#ifdef CONFIG_PREEMPT_RT_BASE
+       tsk->posix_timer_list = NULL;
+#endif
        tsk->cputime_expires.prof_exp = 0;
        tsk->cputime_expires.virt_exp = 0;
        tsk->cputime_expires.sched_exp = 0;
@@ -1606,6 +1647,7 @@ static __latent_entropy struct task_struct *copy_process(
        spin_lock_init(&p->alloc_lock);
 
        init_sigpending(&p->pending);
+       p->sigqueue_cache = NULL;
 
        p->utime = p->stime = p->gtime = 0;
        p->utimescaled = p->stimescaled = 0;
index 7123d9c..0279bf7 100644 (file)
@@ -818,7 +818,7 @@ static int refill_pi_state_cache(void)
        return 0;
 }
 
-static struct futex_pi_state * alloc_pi_state(void)
+static struct futex_pi_state *alloc_pi_state(void)
 {
        struct futex_pi_state *pi_state = current->pi_state_cache;
 
@@ -828,11 +828,14 @@ static struct futex_pi_state * alloc_pi_state(void)
        return pi_state;
 }
 
+static void get_pi_state(struct futex_pi_state *pi_state)
+{
+       WARN_ON_ONCE(!atomic_inc_not_zero(&pi_state->refcount));
+}
+
 /*
  * Drops a reference to the pi_state object and frees or caches it
  * when the last reference is gone.
- *
- * Must be called with the hb lock held.
  */
 static void put_pi_state(struct futex_pi_state *pi_state)
 {
@@ -847,16 +850,22 @@ static void put_pi_state(struct futex_pi_state *pi_state)
         * and has cleaned up the pi_state already
         */
        if (pi_state->owner) {
-               raw_spin_lock_irq(&pi_state->owner->pi_lock);
-               list_del_init(&pi_state->list);
-               raw_spin_unlock_irq(&pi_state->owner->pi_lock);
-
-               rt_mutex_proxy_unlock(&pi_state->pi_mutex, pi_state->owner);
+               struct task_struct *owner;
+
+               raw_spin_lock_irq(&pi_state->pi_mutex.wait_lock);
+               owner = pi_state->owner;
+               if (owner) {
+                       raw_spin_lock(&owner->pi_lock);
+                       list_del_init(&pi_state->list);
+                       raw_spin_unlock(&owner->pi_lock);
+               }
+               rt_mutex_proxy_unlock(&pi_state->pi_mutex, owner);
+               raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);
        }
 
-       if (current->pi_state_cache)
+       if (current->pi_state_cache) {
                kfree(pi_state);
-       else {
+       else {
                /*
                 * pi_state->list is already empty.
                 * clear pi_state->owner.
@@ -872,7 +881,7 @@ static void put_pi_state(struct futex_pi_state *pi_state)
  * Look up the task based on what TID userspace gave us.
  * We dont trust it.
  */
-static struct task_struct * futex_find_get_task(pid_t pid)
+static struct task_struct *futex_find_get_task(pid_t pid)
 {
        struct task_struct *p;
 
@@ -907,22 +916,43 @@ void exit_pi_state_list(struct task_struct *curr)
         */
        raw_spin_lock_irq(&curr->pi_lock);
        while (!list_empty(head)) {
-
                next = head->next;
                pi_state = list_entry(next, struct futex_pi_state, list);
                key = pi_state->key;
                hb = hash_futex(&key);
+
+               /*
+                * We can race against put_pi_state() removing itself from the
+                * list (a waiter going away). put_pi_state() will first
+                * decrement the reference count and then modify the list, so
+                * its possible to see the list entry but fail this reference
+                * acquire.
+                *
+                * In that case; drop the locks to let put_pi_state() make
+                * progress and retry the loop.
+                */
+               if (!atomic_inc_not_zero(&pi_state->refcount)) {
+                       raw_spin_unlock_irq(&curr->pi_lock);
+                       cpu_relax();
+                       raw_spin_lock_irq(&curr->pi_lock);
+                       continue;
+               }
                raw_spin_unlock_irq(&curr->pi_lock);
 
                spin_lock(&hb->lock);
-
-               raw_spin_lock_irq(&curr->pi_lock);
+               raw_spin_lock_irq(&pi_state->pi_mutex.wait_lock);
+               raw_spin_lock(&curr->pi_lock);
                /*
                 * We dropped the pi-lock, so re-check whether this
                 * task still owns the PI-state:
                 */
                if (head->next != next) {
+                       /* retain curr->pi_lock for the loop invariant */
+                       raw_spin_unlock(&curr->pi_lock);
+                       raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);
                        spin_unlock(&hb->lock);
+                       raw_spin_lock_irq(&curr->pi_lock);
+                       put_pi_state(pi_state);
                        continue;
                }
 
@@ -930,12 +960,14 @@ void exit_pi_state_list(struct task_struct *curr)
                WARN_ON(list_empty(&pi_state->list));
                list_del_init(&pi_state->list);
                pi_state->owner = NULL;
-               raw_spin_unlock_irq(&curr->pi_lock);
-
-               rt_mutex_unlock(&pi_state->pi_mutex);
 
+               raw_spin_unlock(&curr->pi_lock);
+               raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);
                spin_unlock(&hb->lock);
 
+               rt_mutex_futex_unlock(&pi_state->pi_mutex);
+               put_pi_state(pi_state);
+
                raw_spin_lock_irq(&curr->pi_lock);
        }
        raw_spin_unlock_irq(&curr->pi_lock);
@@ -989,6 +1021,39 @@ void exit_pi_state_list(struct task_struct *curr)
  *
  * [10] There is no transient state which leaves owner and user space
  *     TID out of sync.
+ *
+ *
+ * Serialization and lifetime rules:
+ *
+ * hb->lock:
+ *
+ *     hb -> futex_q, relation
+ *     futex_q -> pi_state, relation
+ *
+ *     (cannot be raw because hb can contain arbitrary amount
+ *      of futex_q's)
+ *
+ * pi_mutex->wait_lock:
+ *
+ *     {uval, pi_state}
+ *
+ *     (and pi_mutex 'obviously')
+ *
+ * p->pi_lock:
+ *
+ *     p->pi_state_list -> pi_state->list, relation
+ *
+ * pi_state->refcount:
+ *
+ *     pi_state lifetime
+ *
+ *
+ * Lock order:
+ *
+ *   hb->lock
+ *     pi_mutex->wait_lock
+ *       p->pi_lock
+ *
  */
 
 /*
@@ -996,10 +1061,13 @@ void exit_pi_state_list(struct task_struct *curr)
  * the pi_state against the user space value. If correct, attach to
  * it.
  */
-static int attach_to_pi_state(u32 uval, struct futex_pi_state *pi_state,
+static int attach_to_pi_state(u32 __user *uaddr, u32 uval,
+                             struct futex_pi_state *pi_state,
                              struct futex_pi_state **ps)
 {
        pid_t pid = uval & FUTEX_TID_MASK;
+       u32 uval2;
+       int ret;
 
        /*
         * Userspace might have messed up non-PI and PI futexes [3]
@@ -1007,9 +1075,39 @@ static int attach_to_pi_state(u32 uval, struct futex_pi_state *pi_state,
        if (unlikely(!pi_state))
                return -EINVAL;
 
+       /*
+        * We get here with hb->lock held, and having found a
+        * futex_top_waiter(). This means that futex_lock_pi() of said futex_q
+        * has dropped the hb->lock in between queue_me() and unqueue_me_pi(),
+        * which in turn means that futex_lock_pi() still has a reference on
+        * our pi_state.
+        *
+        * The waiter holding a reference on @pi_state also protects against
+        * the unlocked put_pi_state() in futex_unlock_pi(), futex_lock_pi()
+        * and futex_wait_requeue_pi() as it cannot go to 0 and consequently
+        * free pi_state before we can take a reference ourselves.
+        */
        WARN_ON(!atomic_read(&pi_state->refcount));
 
        /*
+        * Now that we have a pi_state, we can acquire wait_lock
+        * and do the state validation.
+        */
+       raw_spin_lock_irq(&pi_state->pi_mutex.wait_lock);
+
+       /*
+        * Since {uval, pi_state} is serialized by wait_lock, and our current
+        * uval was read without holding it, it can have changed. Verify it
+        * still is what we expect it to be, otherwise retry the entire
+        * operation.
+        */
+       if (get_futex_value_locked(&uval2, uaddr))
+               goto out_efault;
+
+       if (uval != uval2)
+               goto out_eagain;
+
+       /*
         * Handle the owner died case:
         */
        if (uval & FUTEX_OWNER_DIED) {
@@ -1024,11 +1122,11 @@ static int attach_to_pi_state(u32 uval, struct futex_pi_state *pi_state,
                         * is not 0. Inconsistent state. [5]
                         */
                        if (pid)
-                               return -EINVAL;
+                               goto out_einval;
                        /*
                         * Take a ref on the state and return success. [4]
                         */
-                       goto out_state;
+                       goto out_attach;
                }
 
                /*
@@ -1040,14 +1138,14 @@ static int attach_to_pi_state(u32 uval, struct futex_pi_state *pi_state,
                 * Take a ref on the state and return success. [6]
                 */
                if (!pid)
-                       goto out_state;
+                       goto out_attach;
        } else {
                /*
                 * If the owner died bit is not set, then the pi_state
                 * must have an owner. [7]
                 */
                if (!pi_state->owner)
-                       return -EINVAL;
+                       goto out_einval;
        }
 
        /*
@@ -1056,11 +1154,29 @@ static int attach_to_pi_state(u32 uval, struct futex_pi_state *pi_state,
         * user space TID. [9/10]
         */
        if (pid != task_pid_vnr(pi_state->owner))
-               return -EINVAL;
-out_state:
-       atomic_inc(&pi_state->refcount);
+               goto out_einval;
+
+out_attach:
+       get_pi_state(pi_state);
+       raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);
        *ps = pi_state;
        return 0;
+
+out_einval:
+       ret = -EINVAL;
+       goto out_error;
+
+out_eagain:
+       ret = -EAGAIN;
+       goto out_error;
+
+out_efault:
+       ret = -EFAULT;
+       goto out_error;
+
+out_error:
+       raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);
+       return ret;
 }
 
 /*
@@ -1111,6 +1227,9 @@ static int attach_to_pi_owner(u32 uval, union futex_key *key,
 
        /*
         * No existing pi state. First waiter. [2]
+        *
+        * This creates pi_state, we have hb->lock held, this means nothing can
+        * observe this state, wait_lock is irrelevant.
         */
        pi_state = alloc_pi_state();
 
@@ -1125,6 +1244,10 @@ static int attach_to_pi_owner(u32 uval, union futex_key *key,
 
        WARN_ON(!list_empty(&pi_state->list));
        list_add(&pi_state->list, &p->pi_state_list);
+       /*
+        * Assignment without holding pi_state->pi_mutex.wait_lock is safe
+        * because there is no concurrency as the object is not published yet.
+        */
        pi_state->owner = p;
        raw_spin_unlock_irq(&p->pi_lock);
 
@@ -1135,17 +1258,18 @@ static int attach_to_pi_owner(u32 uval, union futex_key *key,
        return 0;
 }
 
-static int lookup_pi_state(u32 uval, struct futex_hash_bucket *hb,
+static int lookup_pi_state(u32 __user *uaddr, u32 uval,
+                          struct futex_hash_bucket *hb,
                           union futex_key *key, struct futex_pi_state **ps)
 {
-       struct futex_q *match = futex_top_waiter(hb, key);
+       struct futex_q *top_waiter = futex_top_waiter(hb, key);
 
        /*
         * If there is a waiter on that futex, validate it and
         * attach to the pi_state when the validation succeeds.
         */
-       if (match)
-               return attach_to_pi_state(uval, match->pi_state, ps);
+       if (top_waiter)
+               return attach_to_pi_state(uaddr, uval, top_waiter->pi_state, ps);
 
        /*
         * We are the first waiter - try to look up the owner based on
@@ -1164,7 +1288,7 @@ static int lock_pi_update_atomic(u32 __user *uaddr, u32 uval, u32 newval)
        if (unlikely(cmpxchg_futex_value_locked(&curval, uaddr, uval, newval)))
                return -EFAULT;
 
-       /*If user space value changed, let the caller retry */
+       /* If user space value changed, let the caller retry */
        return curval != uval ? -EAGAIN : 0;
 }
 
@@ -1192,7 +1316,7 @@ static int futex_lock_pi_atomic(u32 __user *uaddr, struct futex_hash_bucket *hb,
                                struct task_struct *task, int set_waiters)
 {
        u32 uval, newval, vpid = task_pid_vnr(task);
-       struct futex_q *match;
+       struct futex_q *top_waiter;
        int ret;
 
        /*
@@ -1218,9 +1342,9 @@ static int futex_lock_pi_atomic(u32 __user *uaddr, struct futex_hash_bucket *hb,
         * Lookup existing state first. If it exists, try to attach to
         * its pi_state.
         */
-       match = futex_top_waiter(hb, key);
-       if (match)
-               return attach_to_pi_state(uval, match->pi_state, ps);
+       top_waiter = futex_top_waiter(hb, key);
+       if (top_waiter)
+               return attach_to_pi_state(uaddr, uval, top_waiter->pi_state, ps);
 
        /*
         * No waiter and user TID is 0. We are here because the
@@ -1301,50 +1425,45 @@ static void mark_wake_futex(struct wake_q_head *wake_q, struct futex_q *q)
        wake_q_add(wake_q, p);
        __unqueue_futex(q);
        /*
-        * The waiting task can free the futex_q as soon as
-        * q->lock_ptr = NULL is written, without taking any locks. A
-        * memory barrier is required here to prevent the following
-        * store to lock_ptr from getting ahead of the plist_del.
+        * The waiting task can free the futex_q as soon as q->lock_ptr = NULL
+        * is written, without taking any locks. This is possible in the event
+        * of a spurious wakeup, for example. A memory barrier is required here
+        * to prevent the following store to lock_ptr from getting ahead of the
+        * plist_del in __unqueue_futex().
         */
-       smp_wmb();
-       q->lock_ptr = NULL;
+       smp_store_release(&q->lock_ptr, NULL);
 }
 
-static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *this,
-                        struct futex_hash_bucket *hb)
+/*
+ * Caller must hold a reference on @pi_state.
+ */
+static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_pi_state *pi_state)
 {
-       struct task_struct *new_owner;
-       struct futex_pi_state *pi_state = this->pi_state;
        u32 uninitialized_var(curval), newval;
+       struct task_struct *new_owner;
+       bool postunlock = false;
        WAKE_Q(wake_q);
-       bool deboost;
+       WAKE_Q(wake_sleeper_q);
        int ret = 0;
 
-       if (!pi_state)
-               return -EINVAL;
-
-       /*
-        * If current does not own the pi_state then the futex is
-        * inconsistent and user space fiddled with the futex value.
-        */
-       if (pi_state->owner != current)
-               return -EINVAL;
-
-       raw_spin_lock_irq(&pi_state->pi_mutex.wait_lock);
        new_owner = rt_mutex_next_owner(&pi_state->pi_mutex);
+       if (WARN_ON_ONCE(!new_owner)) {
+               /*
+                * As per the comment in futex_unlock_pi() this should not happen.
+                *
+                * When this happens, give up our locks and try again, giving
+                * the futex_lock_pi() instance time to complete, either by
+                * waiting on the rtmutex or removing itself from the futex
+                * queue.
+                */
+               ret = -EAGAIN;
+               goto out_unlock;
+       }
 
        /*
-        * It is possible that the next waiter (the one that brought
-        * this owner to the kernel) timed out and is no longer
-        * waiting on the lock.
-        */
-       if (!new_owner)
-               new_owner = this->task;
-
-       /*
-        * We pass it to the next owner. The WAITERS bit is always
-        * kept enabled while there is PI state around. We cleanup the
-        * owner died bit, because we are the owner.
+        * We pass it to the next owner. The WAITERS bit is always kept
+        * enabled while there is PI state around. We cleanup the owner
+        * died bit, because we are the owner.
         */
        newval = FUTEX_WAITERS | task_pid_vnr(new_owner);
 
@@ -1353,6 +1472,7 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *this,
 
        if (cmpxchg_futex_value_locked(&curval, uaddr, uval, newval)) {
                ret = -EFAULT;
+
        } else if (curval != uval) {
                /*
                 * If a unconditional UNLOCK_PI operation (user space did not
@@ -1365,10 +1485,14 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *this,
                else
                        ret = -EINVAL;
        }
-       if (ret) {
-               raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);
-               return ret;
-       }
+
+       if (ret)
+               goto out_unlock;
+
+       /*
+        * This is a point of no return; once we modify the uval there is no
+        * going back and subsequent operations must not fail.
+        */
 
        raw_spin_lock(&pi_state->owner->pi_lock);
        WARN_ON(list_empty(&pi_state->list));
@@ -1381,22 +1505,15 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *this,
        pi_state->owner = new_owner;
        raw_spin_unlock(&new_owner->pi_lock);
 
+       postunlock = __rt_mutex_futex_unlock(&pi_state->pi_mutex, &wake_q,
+                                            &wake_sleeper_q);
+out_unlock:
        raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);
 
-       deboost = rt_mutex_futex_unlock(&pi_state->pi_mutex, &wake_q);
-
-       /*
-        * First unlock HB so the waiter does not spin on it once he got woken
-        * up. Second wake up the waiter before the priority is adjusted. If we
-        * deboost first (and lose our higher priority), then the task might get
-        * scheduled away before the wake up can take place.
-        */
-       spin_unlock(&hb->lock);
-       wake_up_q(&wake_q);
-       if (deboost)
-               rt_mutex_adjust_prio(current);
+       if (postunlock)
+               rt_mutex_postunlock(&wake_q, &wake_sleeper_q);
 
-       return 0;
+       return ret;
 }
 
 /*
@@ -1892,7 +2009,7 @@ retry_private:
                         * If that call succeeds then we have pi_state and an
                         * initial refcount on it.
                         */
-                       ret = lookup_pi_state(ret, hb2, &key2, &pi_state);
+                       ret = lookup_pi_state(uaddr2, ret, hb2, &key2, &pi_state);
                }
 
                switch (ret) {
@@ -1975,7 +2092,7 @@ retry_private:
                         * refcount on the pi_state and store the pointer in
                         * the futex_q object of the waiter.
                         */
-                       atomic_inc(&pi_state->refcount);
+                       get_pi_state(pi_state);
                        this->pi_state = pi_state;
                        ret = rt_mutex_start_proxy_lock(&pi_state->pi_mutex,
                                                        this->rt_waiter,
@@ -1992,6 +2109,16 @@ retry_private:
                                requeue_pi_wake_futex(this, &key2, hb2);
                                drop_count++;
                                continue;
+                       } else if (ret == -EAGAIN) {
+                               /*
+                                * Waiter was woken by timeout or
+                                * signal and has set pi_blocked_on to
+                                * PI_WAKEUP_INPROGRESS before we
+                                * tried to enqueue it on the rtmutex.
+                                */
+                               this->pi_state = NULL;
+                               put_pi_state(pi_state);
+                               continue;
                        } else if (ret) {
                                /*
                                 * rt_mutex_start_proxy_lock() detected a
@@ -2075,20 +2202,7 @@ queue_unlock(struct futex_hash_bucket *hb)
        hb_waiters_dec(hb);
 }
 
-/**
- * queue_me() - Enqueue the futex_q on the futex_hash_bucket
- * @q: The futex_q to enqueue
- * @hb:        The destination hash bucket
- *
- * The hb->lock must be held by the caller, and is released here. A call to
- * queue_me() is typically paired with exactly one call to unqueue_me().  The
- * exceptions involve the PI related operations, which may use unqueue_me_pi()
- * or nothing if the unqueue is done as part of the wake process and the unqueue
- * state is implicit in the state of woken task (see futex_wait_requeue_pi() for
- * an example).
- */
-static inline void queue_me(struct futex_q *q, struct futex_hash_bucket *hb)
-       __releases(&hb->lock)
+static inline void __queue_me(struct futex_q *q, struct futex_hash_bucket *hb)
 {
        int prio;
 
@@ -2105,6 +2219,24 @@ static inline void queue_me(struct futex_q *q, struct futex_hash_bucket *hb)
        plist_node_init(&q->list, prio);
        plist_add(&q->list, &hb->chain);
        q->task = current;
+}
+
+/**
+ * queue_me() - Enqueue the futex_q on the futex_hash_bucket
+ * @q: The futex_q to enqueue
+ * @hb:        The destination hash bucket
+ *
+ * The hb->lock must be held by the caller, and is released here. A call to
+ * queue_me() is typically paired with exactly one call to unqueue_me().  The
+ * exceptions involve the PI related operations, which may use unqueue_me_pi()
+ * or nothing if the unqueue is done as part of the wake process and the unqueue
+ * state is implicit in the state of woken task (see futex_wait_requeue_pi() for
+ * an example).
+ */
+static inline void queue_me(struct futex_q *q, struct futex_hash_bucket *hb)
+       __releases(&hb->lock)
+{
+       __queue_me(q, hb);
        spin_unlock(&hb->lock);
 }
 
@@ -2180,47 +2312,88 @@ static void unqueue_me_pi(struct futex_q *q)
        spin_unlock(q->lock_ptr);
 }
 
-/*
- * Fixup the pi_state owner with the new owner.
- *
- * Must be called with hash bucket lock held and mm->sem held for non
- * private futexes.
- */
 static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q,
-                               struct task_struct *newowner)
+                               struct task_struct *argowner)
 {
-       u32 newtid = task_pid_vnr(newowner) | FUTEX_WAITERS;
        struct futex_pi_state *pi_state = q->pi_state;
-       struct task_struct *oldowner = pi_state->owner;
        u32 uval, uninitialized_var(curval), newval;
+       struct task_struct *oldowner, *newowner;
+       u32 newtid;
        int ret;
 
-       /* Owner died? */
-       if (!pi_state->owner)
-               newtid |= FUTEX_OWNER_DIED;
+       lockdep_assert_held(q->lock_ptr);
+
+       raw_spin_lock_irq(&pi_state->pi_mutex.wait_lock);
+
+       oldowner = pi_state->owner;
 
        /*
-        * We are here either because we stole the rtmutex from the
-        * previous highest priority waiter or we are the highest priority
-        * waiter but failed to get the rtmutex the first time.
-        * We have to replace the newowner TID in the user space variable.
+        * We are here because either:
+        *
+        *  - we stole the lock and pi_state->owner needs updating to reflect
+        *    that (@argowner == current),
+        *
+        * or:
+        *
+        *  - someone stole our lock and we need to fix things to point to the
+        *    new owner (@argowner == NULL).
+        *
+        * Either way, we have to replace the TID in the user space variable.
         * This must be atomic as we have to preserve the owner died bit here.
         *
         * Note: We write the user space value _before_ changing the pi_state
         * because we can fault here. Imagine swapped out pages or a fork
         * that marked all the anonymous memory readonly for cow.
         *
-        * Modifying pi_state _before_ the user space value would
-        * leave the pi_state in an inconsistent state when we fault
-        * here, because we need to drop the hash bucket lock to
-        * handle the fault. This might be observed in the PID check
-        * in lookup_pi_state.
+        * Modifying pi_state _before_ the user space value would leave the
+        * pi_state in an inconsistent state when we fault here, because we
+        * need to drop the locks to handle the fault. This might be observed
+        * in the PID check in lookup_pi_state.
         */
 retry:
+       if (!argowner) {
+               if (oldowner != current) {
+                       /*
+                        * We raced against a concurrent self; things are
+                        * already fixed up. Nothing to do.
+                        */
+                       ret = 0;
+                       goto out_unlock;
+               }
+
+               if (__rt_mutex_futex_trylock(&pi_state->pi_mutex)) {
+                       /* We got the lock after all, nothing to fix. */
+                       ret = 0;
+                       goto out_unlock;
+               }
+
+               /*
+                * Since we just failed the trylock; there must be an owner.
+                */
+               newowner = rt_mutex_owner(&pi_state->pi_mutex);
+               BUG_ON(!newowner);
+       } else {
+               WARN_ON_ONCE(argowner != current);
+               if (oldowner == current) {
+                       /*
+                        * We raced against a concurrent self; things are
+                        * already fixed up. Nothing to do.
+                        */
+                       ret = 0;
+                       goto out_unlock;
+               }
+               newowner = argowner;
+       }
+
+       newtid = task_pid_vnr(newowner) | FUTEX_WAITERS;
+       /* Owner died? */
+       if (!pi_state->owner)
+               newtid |= FUTEX_OWNER_DIED;
+
        if (get_futex_value_locked(&uval, uaddr))
                goto handle_fault;
 
-       while (1) {
+       for (;;) {
                newval = (uval & FUTEX_OWNER_DIED) | newtid;
 
                if (cmpxchg_futex_value_locked(&curval, uaddr, uval, newval))
@@ -2235,47 +2408,60 @@ retry:
         * itself.
         */
        if (pi_state->owner != NULL) {
-               raw_spin_lock_irq(&pi_state->owner->pi_lock);
+               raw_spin_lock(&pi_state->owner->pi_lock);
                WARN_ON(list_empty(&pi_state->list));
                list_del_init(&pi_state->list);
-               raw_spin_unlock_irq(&pi_state->owner->pi_lock);
+               raw_spin_unlock(&pi_state->owner->pi_lock);
        }
 
        pi_state->owner = newowner;
 
-       raw_spin_lock_irq(&newowner->pi_lock);
+       raw_spin_lock(&newowner->pi_lock);
        WARN_ON(!list_empty(&pi_state->list));
        list_add(&pi_state->list, &newowner->pi_state_list);
-       raw_spin_unlock_irq(&newowner->pi_lock);
+       raw_spin_unlock(&newowner->pi_lock);
+       raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);
+
        return 0;
 
        /*
-        * To handle the page fault we need to drop the hash bucket
-        * lock here. That gives the other task (either the highest priority
-        * waiter itself or the task which stole the rtmutex) the
-        * chance to try the fixup of the pi_state. So once we are
-        * back from handling the fault we need to check the pi_state
-        * after reacquiring the hash bucket lock and before trying to
-        * do another fixup. When the fixup has been done already we
-        * simply return.
+        * To handle the page fault we need to drop the locks here. That gives
+        * the other task (either the highest priority waiter itself or the
+        * task which stole the rtmutex) the chance to try the fixup of the
+        * pi_state. So once we are back from handling the fault we need to
+        * check the pi_state after reacquiring the locks and before trying to
+        * do another fixup. When the fixup has been done already we simply
+        * return.
+        *
+        * Note: we hold both hb->lock and pi_mutex->wait_lock. We can safely
+        * drop hb->lock since the caller owns the hb -> futex_q relation.
+        * Dropping the pi_mutex->wait_lock requires the state revalidate.
         */
 handle_fault:
+       raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);
        spin_unlock(q->lock_ptr);
 
        ret = fault_in_user_writeable(uaddr);
 
        spin_lock(q->lock_ptr);
+       raw_spin_lock_irq(&pi_state->pi_mutex.wait_lock);
 
        /*
         * Check if someone else fixed it for us:
         */
-       if (pi_state->owner != oldowner)
-               return 0;
+       if (pi_state->owner != oldowner) {
+               ret = 0;
+               goto out_unlock;
+       }
 
        if (ret)
-               return ret;
+               goto out_unlock;
 
        goto retry;
+
+out_unlock:
+       raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);
+       return ret;
 }
 
 static long futex_wait_restart(struct restart_block *restart);
@@ -2297,13 +2483,16 @@ static long futex_wait_restart(struct restart_block *restart);
  */
 static int fixup_owner(u32 __user *uaddr, struct futex_q *q, int locked)
 {
-       struct task_struct *owner;
        int ret = 0;
 
        if (locked) {
                /*
                 * Got the lock. We might not be the anticipated owner if we
                 * did a lock-steal - fix up the PI-state in that case:
+                *
+                * Speculative pi_state->owner read (we don't hold wait_lock);
+                * since we own the lock pi_state->owner == current is the
+                * stable state, anything else needs more attention.
                 */
                if (q->pi_state->owner != current)
                        ret = fixup_pi_state_owner(uaddr, q, current);
@@ -2311,31 +2500,15 @@ static int fixup_owner(u32 __user *uaddr, struct futex_q *q, int locked)
        }
 
        /*
-        * Catch the rare case, where the lock was released when we were on the
-        * way back before we locked the hash bucket.
+        * If we didn't get the lock; check if anybody stole it from us. In
+        * that case, we need to fix up the uval to point to them instead of
+        * us, otherwise bad things happen. [10]
+        *
+        * Another speculative read; pi_state->owner == current is unstable
+        * but needs our attention.
         */
        if (q->pi_state->owner == current) {
-               /*
-                * Try to get the rt_mutex now. This might fail as some other
-                * task acquired the rt_mutex after we removed ourself from the
-                * rt_mutex waiters list.
-                */
-               if (rt_mutex_trylock(&q->pi_state->pi_mutex)) {
-                       locked = 1;
-                       goto out;
-               }
-
-               /*
-                * pi_state is incorrect, some other task did a lock steal and
-                * we returned due to timeout or signal without taking the
-                * rt_mutex. Too late.
-                */
-               raw_spin_lock_irq(&q->pi_state->pi_mutex.wait_lock);
-               owner = rt_mutex_owner(&q->pi_state->pi_mutex);
-               if (!owner)
-                       owner = rt_mutex_next_owner(&q->pi_state->pi_mutex);
-               raw_spin_unlock_irq(&q->pi_state->pi_mutex.wait_lock);
-               ret = fixup_pi_state_owner(uaddr, q, owner);
+               ret = fixup_pi_state_owner(uaddr, q, NULL);
                goto out;
        }
 
@@ -2343,11 +2516,12 @@ static int fixup_owner(u32 __user *uaddr, struct futex_q *q, int locked)
         * Paranoia check. If we did not take the lock, then we should not be
         * the owner of the rt_mutex.
         */
-       if (rt_mutex_owner(&q->pi_state->pi_mutex) == current)
+       if (rt_mutex_owner(&q->pi_state->pi_mutex) == current) {
                printk(KERN_ERR "fixup_owner: ret = %d pi-mutex: %p "
                                "pi-state %p\n", ret,
                                q->pi_state->pi_mutex.owner,
                                q->pi_state->owner);
+       }
 
 out:
        return ret ? ret : locked;
@@ -2571,6 +2745,8 @@ static int futex_lock_pi(u32 __user *uaddr, unsigned int flags,
                         ktime_t *time, int trylock)
 {
        struct hrtimer_sleeper timeout, *to = NULL;
+       struct futex_pi_state *pi_state = NULL;
+       struct rt_mutex_waiter rt_waiter;
        struct futex_hash_bucket *hb;
        struct futex_q q = futex_q_init;
        int res, ret;
@@ -2623,25 +2799,77 @@ retry_private:
                }
        }
 
+       WARN_ON(!q.pi_state);
+
        /*
         * Only actually queue now that the atomic ops are done:
         */
-       queue_me(&q, hb);
+       __queue_me(&q, hb);
 
-       WARN_ON(!q.pi_state);
-       /*
-        * Block on the PI mutex:
-        */
-       if (!trylock) {
-               ret = rt_mutex_timed_futex_lock(&q.pi_state->pi_mutex, to);
-       } else {
-               ret = rt_mutex_trylock(&q.pi_state->pi_mutex);
+       if (trylock) {
+               ret = rt_mutex_futex_trylock(&q.pi_state->pi_mutex);
                /* Fixup the trylock return value: */
                ret = ret ? 0 : -EWOULDBLOCK;
+               goto no_block;
        }
 
+       rt_mutex_init_waiter(&rt_waiter, false);
+
+       /*
+        * On PREEMPT_RT_FULL, when hb->lock becomes an rt_mutex, we must not
+        * hold it while doing rt_mutex_start_proxy(), because then it will
+        * include hb->lock in the blocking chain, even through we'll not in
+        * fact hold it while blocking. This will lead it to report -EDEADLK
+        * and BUG when futex_unlock_pi() interleaves with this.
+        *
+        * Therefore acquire wait_lock while holding hb->lock, but drop the
+        * latter before calling rt_mutex_start_proxy_lock(). This still fully
+        * serializes against futex_unlock_pi() as that does the exact same
+        * lock handoff sequence.
+        */
+       raw_spin_lock_irq(&q.pi_state->pi_mutex.wait_lock);
+       /*
+        * the migrate_disable() here disables migration in the in_atomic() fast
+        * path which is enabled again in the following spin_unlock(). We have
+        * one migrate_disable() pending in the slow-path which is reversed
+        * after the raw_spin_unlock_irq() where we leave the atomic context.
+        */
+       migrate_disable();
+
+       spin_unlock(q.lock_ptr);
+       ret = __rt_mutex_start_proxy_lock(&q.pi_state->pi_mutex, &rt_waiter, current);
+       raw_spin_unlock_irq(&q.pi_state->pi_mutex.wait_lock);
+       migrate_enable();
+
+       if (ret) {
+               if (ret == 1)
+                       ret = 0;
+
+               spin_lock(q.lock_ptr);
+               goto no_block;
+       }
+
+
+       if (unlikely(to))
+               hrtimer_start_expires(&to->timer, HRTIMER_MODE_ABS);
+
+       ret = rt_mutex_wait_proxy_lock(&q.pi_state->pi_mutex, to, &rt_waiter);
+
        spin_lock(q.lock_ptr);
        /*
+        * If we failed to acquire the lock (signal/timeout), we must
+        * first acquire the hb->lock before removing the lock from the
+        * rt_mutex waitqueue, such that we can keep the hb and rt_mutex
+        * wait lists consistent.
+        *
+        * In particular; it is important that futex_unlock_pi() can not
+        * observe this inconsistency.
+        */
+       if (ret && !rt_mutex_cleanup_proxy_lock(&q.pi_state->pi_mutex, &rt_waiter))
+               ret = 0;
+
+no_block:
+       /*
         * Fixup the pi_state owner and possibly acquire the lock if we
         * haven't already.
         */
@@ -2657,12 +2885,19 @@ retry_private:
         * If fixup_owner() faulted and was unable to handle the fault, unlock
         * it and return the fault to userspace.
         */
-       if (ret && (rt_mutex_owner(&q.pi_state->pi_mutex) == current))
-               rt_mutex_unlock(&q.pi_state->pi_mutex);
+       if (ret && (rt_mutex_owner(&q.pi_state->pi_mutex) == current)) {
+               pi_state = q.pi_state;
+               get_pi_state(pi_state);
+       }
 
        /* Unqueue and drop the lock */
        unqueue_me_pi(&q);
 
+       if (pi_state) {
+               rt_mutex_futex_unlock(&pi_state->pi_mutex);
+               put_pi_state(pi_state);
+       }
+
        goto out_put_key;
 
 out_unlock_put_key:
@@ -2671,8 +2906,10 @@ out_unlock_put_key:
 out_put_key:
        put_futex_key(&q.key);
 out:
-       if (to)
+       if (to) {
+               hrtimer_cancel(&to->timer);
                destroy_hrtimer_on_stack(&to->timer);
+       }
        return ret != -EINTR ? ret : -ERESTARTNOINTR;
 
 uaddr_faulted:
@@ -2699,7 +2936,7 @@ static int futex_unlock_pi(u32 __user *uaddr, unsigned int flags)
        u32 uninitialized_var(curval), uval, vpid = task_pid_vnr(current);
        union futex_key key = FUTEX_KEY_INIT;
        struct futex_hash_bucket *hb;
-       struct futex_q *match;
+       struct futex_q *top_waiter;
        int ret;
 
 retry:
@@ -2723,12 +2960,48 @@ retry:
         * all and we at least want to know if user space fiddled
         * with the futex value instead of blindly unlocking.
         */
-       match = futex_top_waiter(hb, &key);
-       if (match) {
-               ret = wake_futex_pi(uaddr, uval, match, hb);
+       top_waiter = futex_top_waiter(hb, &key);
+       if (top_waiter) {
+               struct futex_pi_state *pi_state = top_waiter->pi_state;
+
+               ret = -EINVAL;
+               if (!pi_state)
+                       goto out_unlock;
+
+               /*
+                * If current does not own the pi_state then the futex is
+                * inconsistent and user space fiddled with the futex value.
+                */
+               if (pi_state->owner != current)
+                       goto out_unlock;
+
+               get_pi_state(pi_state);
+               /*
+                * By taking wait_lock while still holding hb->lock, we ensure
+                * there is no point where we hold neither; and therefore
+                * wake_futex_pi() must observe a state consistent with what we
+                * observed.
+                */
+               raw_spin_lock_irq(&pi_state->pi_mutex.wait_lock);
+               /*
+                * Magic trickery for now to make the RT migrate disable
+                * logic happy. The following spin_unlock() happens with
+                * interrupts disabled so the internal migrate_enable()
+                * won't undo the migrate_disable() which was issued when
+                * locking hb->lock.
+                */
+               migrate_disable();
+               spin_unlock(&hb->lock);
+
+               /* Drops pi_state->pi_mutex.wait_lock */
+               ret = wake_futex_pi(uaddr, uval, pi_state);
+
+               migrate_enable();
+
+               put_pi_state(pi_state);
+
                /*
-                * In case of success wake_futex_pi dropped the hash
-                * bucket lock.
+                * Success, we're done! No tricky corner cases.
                 */
                if (!ret)
                        goto out_putkey;
@@ -2743,7 +3016,6 @@ retry:
                 * setting the FUTEX_WAITERS bit. Try again.
                 */
                if (ret == -EAGAIN) {
-                       spin_unlock(&hb->lock);
                        put_futex_key(&key);
                        goto retry;
                }
@@ -2751,7 +3023,7 @@ retry:
                 * wake_futex_pi has detected invalid state. Tell user
                 * space.
                 */
-               goto out_unlock;
+               goto out_putkey;
        }
 
        /*
@@ -2761,8 +3033,10 @@ retry:
         * preserve the WAITERS bit not the OWNER_DIED one. We are the
         * owner.
         */
-       if (cmpxchg_futex_value_locked(&curval, uaddr, uval, 0))
+       if (cmpxchg_futex_value_locked(&curval, uaddr, uval, 0)) {
+               spin_unlock(&hb->lock);
                goto pi_faulted;
+       }
 
        /*
         * If uval has changed, let user space handle it.
@@ -2776,7 +3050,6 @@ out_putkey:
        return ret;
 
 pi_faulted:
-       spin_unlock(&hb->lock);
        put_futex_key(&key);
 
        ret = fault_in_user_writeable(uaddr);
@@ -2880,8 +3153,9 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
                                 u32 __user *uaddr2)
 {
        struct hrtimer_sleeper timeout, *to = NULL;
+       struct futex_pi_state *pi_state = NULL;
        struct rt_mutex_waiter rt_waiter;
-       struct futex_hash_bucket *hb;
+       struct futex_hash_bucket *hb, *hb2;
        union futex_key key2 = FUTEX_KEY_INIT;
        struct futex_q q = futex_q_init;
        int res, ret;
@@ -2906,10 +3180,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
         * The waiter is allocated on our stack, manipulated by the requeue
         * code while we sleep on uaddr.
         */
-       debug_rt_mutex_init_waiter(&rt_waiter);
-       RB_CLEAR_NODE(&rt_waiter.pi_tree_entry);
-       RB_CLEAR_NODE(&rt_waiter.tree_entry);
-       rt_waiter.task = NULL;
+       rt_mutex_init_waiter(&rt_waiter, false);
 
        ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2, VERIFY_WRITE);
        if (unlikely(ret != 0))
@@ -2940,20 +3211,55 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
        /* Queue the futex_q, drop the hb lock, wait for wakeup. */
        futex_wait_queue_me(hb, &q, to);
 
-       spin_lock(&hb->lock);
-       ret = handle_early_requeue_pi_wakeup(hb, &q, &key2, to);
-       spin_unlock(&hb->lock);
-       if (ret)
-               goto out_put_keys;
+       /*
+        * On RT we must avoid races with requeue and trying to block
+        * on two mutexes (hb->lock and uaddr2's rtmutex) by
+        * serializing access to pi_blocked_on with pi_lock.
+        */
+       raw_spin_lock_irq(&current->pi_lock);
+       if (current->pi_blocked_on) {
+               /*
+                * We have been requeued or are in the process of
+                * being requeued.
+                */
+               raw_spin_unlock_irq(&current->pi_lock);
+       } else {
+               /*
+                * Setting pi_blocked_on to PI_WAKEUP_INPROGRESS
+                * prevents a concurrent requeue from moving us to the
+                * uaddr2 rtmutex. After that we can safely acquire
+                * (and possibly block on) hb->lock.
+                */
+               current->pi_blocked_on = PI_WAKEUP_INPROGRESS;
+               raw_spin_unlock_irq(&current->pi_lock);
+
+               spin_lock(&hb->lock);
+
+               /*
+                * Clean up pi_blocked_on. We might leak it otherwise
+                * when we succeeded with the hb->lock in the fast
+                * path.
+                */
+               raw_spin_lock_irq(&current->pi_lock);
+               current->pi_blocked_on = NULL;
+               raw_spin_unlock_irq(&current->pi_lock);
+
+               ret = handle_early_requeue_pi_wakeup(hb, &q, &key2, to);
+               spin_unlock(&hb->lock);
+               if (ret)
+                       goto out_put_keys;
+       }
 
        /*
-        * In order for us to be here, we know our q.key == key2, and since
-        * we took the hb->lock above, we also know that futex_requeue() has
-        * completed and we no longer have to concern ourselves with a wakeup
-        * race with the atomic proxy lock acquisition by the requeue code. The
-        * futex_requeue dropped our key1 reference and incremented our key2
-        * reference count.
+        * In order to be here, we have either been requeued, are in
+        * the process of being requeued, or requeue successfully
+        * acquired uaddr2 on our behalf.  If pi_blocked_on was
+        * non-null above, we may be racing with a requeue.  Do not
+        * rely on q->lock_ptr to be hb2->lock until after blocking on
+        * hb->lock or hb2->lock. The futex_requeue dropped our key1
+        * reference and incremented our key2 reference count.
         */
+       hb2 = hash_futex(&key2);
 
        /* Check if the requeue code acquired the second futex for us. */
        if (!q.rt_waiter) {
@@ -2962,16 +3268,19 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
                 * did a lock-steal - fix up the PI-state in that case.
                 */
                if (q.pi_state && (q.pi_state->owner != current)) {
-                       spin_lock(q.lock_ptr);
+                       spin_lock(&hb2->lock);
+                       BUG_ON(&hb2->lock != q.lock_ptr);
                        ret = fixup_pi_state_owner(uaddr2, &q, current);
-                       if (ret && rt_mutex_owner(&q.pi_state->pi_mutex) == current)
-                               rt_mutex_unlock(&q.pi_state->pi_mutex);
+                       if (ret && rt_mutex_owner(&q.pi_state->pi_mutex) == current) {
+                               pi_state = q.pi_state;
+                               get_pi_state(pi_state);
+                       }
                        /*
                         * Drop the reference to the pi state which
                         * the requeue_pi() code acquired for us.
                         */
                        put_pi_state(q.pi_state);
-                       spin_unlock(q.lock_ptr);
+                       spin_unlock(&hb2->lock);
                }
        } else {
                struct rt_mutex *pi_mutex;
@@ -2985,7 +3294,8 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
                pi_mutex = &q.pi_state->pi_mutex;
                ret = rt_mutex_wait_proxy_lock(pi_mutex, to, &rt_waiter);
 
-               spin_lock(q.lock_ptr);
+               spin_lock(&hb2->lock);
+               BUG_ON(&hb2->lock != q.lock_ptr);
                if (ret && !rt_mutex_cleanup_proxy_lock(pi_mutex, &rt_waiter))
                        ret = 0;
 
@@ -3007,13 +3317,20 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
                 * the fault, unlock the rt_mutex and return the fault to
                 * userspace.
                 */
-               if (ret && rt_mutex_owner(pi_mutex) == current)
-                       rt_mutex_unlock(pi_mutex);
+               if (ret && rt_mutex_owner(&q.pi_state->pi_mutex) == current) {
+                       pi_state = q.pi_state;
+                       get_pi_state(pi_state);
+               }
 
                /* Unqueue and drop the lock. */
                unqueue_me_pi(&q);
        }
 
+       if (pi_state) {
+               rt_mutex_futex_unlock(&pi_state->pi_mutex);
+               put_pi_state(pi_state);
+       }
+
        if (ret == -EINTR) {
                /*
                 * We've already been requeued, but cannot restart by calling
index 95a322a..c46891f 100644 (file)
@@ -190,10 +190,16 @@ irqreturn_t handle_irq_event_percpu(struct irq_desc *desc)
 {
        irqreturn_t retval;
        unsigned int flags = 0;
+       struct pt_regs *regs = get_irq_regs();
+       u64 ip = regs ? instruction_pointer(regs) : 0;
 
        retval = __handle_irq_event_percpu(desc, &flags);
 
-       add_interrupt_randomness(desc->irq_data.irq, flags);
+#ifdef CONFIG_PREEMPT_RT_FULL
+       desc->random_ip = ip;
+#else
+       add_interrupt_randomness(desc->irq_data.irq, flags, ip);
+#endif
 
        if (!noirqdebug)
                note_interrupt(desc, retval);
index b2fc2a5..2fc96cb 100644 (file)
@@ -22,6 +22,7 @@
 #include "internals.h"
 
 #ifdef CONFIG_IRQ_FORCED_THREADING
+# ifndef CONFIG_PREEMPT_RT_BASE
 __read_mostly bool force_irqthreads;
 
 static int __init setup_forced_irqthreads(char *arg)
@@ -30,6 +31,7 @@ static int __init setup_forced_irqthreads(char *arg)
        return 0;
 }
 early_param("threadirqs", setup_forced_irqthreads);
+# endif
 #endif
 
 static void __synchronize_hardirq(struct irq_desc *desc)
@@ -233,11 +235,12 @@ int irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask,
 
        if (desc->affinity_notify) {
                kref_get(&desc->affinity_notify->kref);
-               if (!schedule_work(&desc->affinity_notify->work)) {
-                       /* Work was already scheduled, drop our extra ref */
-                       kref_put(&desc->affinity_notify->kref,
-                                desc->affinity_notify->release);
-               }
+
+#ifdef CONFIG_PREEMPT_RT_BASE
+               swork_queue(&desc->affinity_notify->swork);
+#else
+               schedule_work(&desc->affinity_notify->work);
+#endif
        }
        irqd_set(data, IRQD_AFFINITY_SET);
 
@@ -275,10 +278,8 @@ int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m)
 }
 EXPORT_SYMBOL_GPL(irq_set_affinity_hint);
 
-static void irq_affinity_notify(struct work_struct *work)
+static void _irq_affinity_notify(struct irq_affinity_notify *notify)
 {
-       struct irq_affinity_notify *notify =
-               container_of(work, struct irq_affinity_notify, work);
        struct irq_desc *desc = irq_to_desc(notify->irq);
        cpumask_var_t cpumask;
        unsigned long flags;
@@ -300,6 +301,35 @@ out:
        kref_put(&notify->kref, notify->release);
 }
 
+#ifdef CONFIG_PREEMPT_RT_BASE
+static void init_helper_thread(void)
+{
+       static int init_sworker_once;
+
+       if (init_sworker_once)
+               return;
+       if (WARN_ON(swork_get()))
+               return;
+       init_sworker_once = 1;
+}
+
+static void irq_affinity_notify(struct swork_event *swork)
+{
+       struct irq_affinity_notify *notify =
+               container_of(swork, struct irq_affinity_notify, swork);
+       _irq_affinity_notify(notify);
+}
+
+#else
+
+static void irq_affinity_notify(struct work_struct *work)
+{
+       struct irq_affinity_notify *notify =
+               container_of(work, struct irq_affinity_notify, work);
+       _irq_affinity_notify(notify);
+}
+#endif
+
 /**
  *     irq_set_affinity_notifier - control notification of IRQ affinity changes
  *     @irq:           Interrupt for which to enable/disable notification
@@ -328,7 +358,12 @@ irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)
        if (notify) {
                notify->irq = irq;
                kref_init(&notify->kref);
+#ifdef CONFIG_PREEMPT_RT_BASE
+               INIT_SWORK(&notify->swork, irq_affinity_notify);
+               init_helper_thread();
+#else
                INIT_WORK(&notify->work, irq_affinity_notify);
+#endif
        }
 
        raw_spin_lock_irqsave(&desc->lock, flags);
@@ -337,10 +372,9 @@ irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)
        raw_spin_unlock_irqrestore(&desc->lock, flags);
 
        if (old_notify) {
-               if (cancel_work_sync(&old_notify->work)) {
-                       /* Pending work had a ref, put that one too */
-                       kref_put(&old_notify->kref, old_notify->release);
-               }
+#ifndef CONFIG_PREEMPT_RT_BASE
+               cancel_work_sync(&old_notify->work);
+#endif
                kref_put(&old_notify->kref, old_notify->release);
        }
 
@@ -891,7 +925,15 @@ irq_forced_thread_fn(struct irq_desc *desc, struct irqaction *action)
                atomic_inc(&desc->threads_handled);
 
        irq_finalize_oneshot(desc, action);
-       local_bh_enable();
+       /*
+        * Interrupts which have real time requirements can be set up
+        * to avoid softirq processing in the thread handler. This is
+        * safe as these interrupts do not raise soft interrupts.
+        */
+       if (irq_settings_no_softirq_call(desc))
+               _local_bh_enable();
+       else
+               local_bh_enable();
        return ret;
 }
 
@@ -989,6 +1031,12 @@ static int irq_thread(void *data)
                if (action_ret == IRQ_WAKE_THREAD)
                        irq_wake_secondary(desc, action);
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+               migrate_disable();
+               add_interrupt_randomness(action->irq, 0,
+                                desc->random_ip ^ (unsigned long) action);
+               migrate_enable();
+#endif
                wake_threads_waitq(desc);
        }
 
@@ -1358,6 +1406,9 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
                        irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
                }
 
+               if (new->flags & IRQF_NO_SOFTIRQ_CALL)
+                       irq_settings_set_no_softirq_call(desc);
+
                /* Set default affinity mask once everything is setup */
                setup_affinity(desc, mask);
 
@@ -2083,7 +2134,7 @@ EXPORT_SYMBOL_GPL(irq_get_irqchip_state);
  *     This call sets the internal irqchip state of an interrupt,
  *     depending on the value of @which.
  *
- *     This function should be called with preemption disabled if the
+ *     This function should be called with migration disabled if the
  *     interrupt controller has per-cpu registers.
  */
 int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
index 320579d..2df2d44 100644 (file)
@@ -16,6 +16,7 @@ enum {
        _IRQ_PER_CPU_DEVID      = IRQ_PER_CPU_DEVID,
        _IRQ_IS_POLLED          = IRQ_IS_POLLED,
        _IRQ_DISABLE_UNLAZY     = IRQ_DISABLE_UNLAZY,
+       _IRQ_NO_SOFTIRQ_CALL    = IRQ_NO_SOFTIRQ_CALL,
        _IRQF_MODIFY_MASK       = IRQF_MODIFY_MASK,
 };
 
@@ -30,6 +31,7 @@ enum {
 #define IRQ_PER_CPU_DEVID      GOT_YOU_MORON
 #define IRQ_IS_POLLED          GOT_YOU_MORON
 #define IRQ_DISABLE_UNLAZY     GOT_YOU_MORON
+#define IRQ_NO_SOFTIRQ_CALL    GOT_YOU_MORON
 #undef IRQF_MODIFY_MASK
 #define IRQF_MODIFY_MASK       GOT_YOU_MORON
 
@@ -40,6 +42,16 @@ irq_settings_clr_and_set(struct irq_desc *desc, u32 clr, u32 set)
        desc->status_use_accessors |= (set & _IRQF_MODIFY_MASK);
 }
 
+static inline bool irq_settings_no_softirq_call(struct irq_desc *desc)
+{
+       return desc->status_use_accessors & _IRQ_NO_SOFTIRQ_CALL;
+}
+
+static inline void irq_settings_set_no_softirq_call(struct irq_desc *desc)
+{
+       desc->status_use_accessors |= _IRQ_NO_SOFTIRQ_CALL;
+}
+
 static inline bool irq_settings_is_per_cpu(struct irq_desc *desc)
 {
        return desc->status_use_accessors & _IRQ_PER_CPU;
index 5707f97..73f38dc 100644 (file)
@@ -442,6 +442,10 @@ MODULE_PARM_DESC(noirqdebug, "Disable irq lockup detection when true");
 
 static int __init irqfixup_setup(char *str)
 {
+#ifdef CONFIG_PREEMPT_RT_BASE
+       pr_warn("irqfixup boot option not supported w/ CONFIG_PREEMPT_RT_BASE\n");
+       return 1;
+#endif
        irqfixup = 1;
        printk(KERN_WARNING "Misrouted IRQ fixup support enabled.\n");
        printk(KERN_WARNING "This may impact system performance.\n");
@@ -454,6 +458,10 @@ module_param(irqfixup, int, 0644);
 
 static int __init irqpoll_setup(char *str)
 {
+#ifdef CONFIG_PREEMPT_RT_BASE
+       pr_warn("irqpoll boot option not supported w/ CONFIG_PREEMPT_RT_BASE\n");
+       return 1;
+#endif
        irqfixup = 2;
        printk(KERN_WARNING "Misrouted IRQ fixup and polling support "
                                "enabled\n");
index bcf107c..2899ba0 100644 (file)
@@ -17,6 +17,7 @@
 #include <linux/cpu.h>
 #include <linux/notifier.h>
 #include <linux/smp.h>
+#include <linux/interrupt.h>
 #include <asm/processor.h>
 
 
@@ -65,6 +66,8 @@ void __weak arch_irq_work_raise(void)
  */
 bool irq_work_queue_on(struct irq_work *work, int cpu)
 {
+       struct llist_head *list;
+
        /* All work should have been flushed before going offline */
        WARN_ON_ONCE(cpu_is_offline(cpu));
 
@@ -75,7 +78,12 @@ bool irq_work_queue_on(struct irq_work *work, int cpu)
        if (!irq_work_claim(work))
                return false;
 
-       if (llist_add(&work->llnode, &per_cpu(raised_list, cpu)))
+       if (IS_ENABLED(CONFIG_PREEMPT_RT_FULL) && !(work->flags & IRQ_WORK_HARD_IRQ))
+               list = &per_cpu(lazy_list, cpu);
+       else
+               list = &per_cpu(raised_list, cpu);
+
+       if (llist_add(&work->llnode, list))
                arch_send_call_function_single_ipi(cpu);
 
        return true;
@@ -86,6 +94,9 @@ EXPORT_SYMBOL_GPL(irq_work_queue_on);
 /* Enqueue the irq work @work on the current CPU */
 bool irq_work_queue(struct irq_work *work)
 {
+       struct llist_head *list;
+       bool lazy_work, realtime = IS_ENABLED(CONFIG_PREEMPT_RT_FULL);
+
        /* Only queue if not already pending */
        if (!irq_work_claim(work))
                return false;
@@ -93,13 +104,15 @@ bool irq_work_queue(struct irq_work *work)
        /* Queue the entry and raise the IPI if needed. */
        preempt_disable();
 
-       /* If the work is "lazy", handle it from next tick if any */
-       if (work->flags & IRQ_WORK_LAZY) {
-               if (llist_add(&work->llnode, this_cpu_ptr(&lazy_list)) &&
-                   tick_nohz_tick_stopped())
-                       arch_irq_work_raise();
-       } else {
-               if (llist_add(&work->llnode, this_cpu_ptr(&raised_list)))
+       lazy_work = work->flags & IRQ_WORK_LAZY;
+
+       if (lazy_work || (realtime && !(work->flags & IRQ_WORK_HARD_IRQ)))
+               list = this_cpu_ptr(&lazy_list);
+       else
+               list = this_cpu_ptr(&raised_list);
+
+       if (llist_add(&work->llnode, list)) {
+               if (!lazy_work || tick_nohz_tick_stopped())
                        arch_irq_work_raise();
        }
 
@@ -116,9 +129,8 @@ bool irq_work_needs_cpu(void)
        raised = this_cpu_ptr(&raised_list);
        lazy = this_cpu_ptr(&lazy_list);
 
-       if (llist_empty(raised) || arch_irq_work_has_interrupt())
-               if (llist_empty(lazy))
-                       return false;
+       if (llist_empty(raised) && llist_empty(lazy))
+               return false;
 
        /* All work should have been flushed before going offline */
        WARN_ON_ONCE(cpu_is_offline(smp_processor_id()));
@@ -132,7 +144,7 @@ static void irq_work_run_list(struct llist_head *list)
        struct irq_work *work;
        struct llist_node *llnode;
 
-       BUG_ON(!irqs_disabled());
+       BUG_ON_NONRT(!irqs_disabled());
 
        if (llist_empty(list))
                return;
@@ -169,7 +181,16 @@ static void irq_work_run_list(struct llist_head *list)
 void irq_work_run(void)
 {
        irq_work_run_list(this_cpu_ptr(&raised_list));
-       irq_work_run_list(this_cpu_ptr(&lazy_list));
+       if (IS_ENABLED(CONFIG_PREEMPT_RT_FULL)) {
+               /*
+                * NOTE: we raise softirq via IPI for safety,
+                * and execute in irq_work_tick() to move the
+                * overhead from hard to soft irq context.
+                */
+               if (!llist_empty(this_cpu_ptr(&lazy_list)))
+                       raise_softirq(TIMER_SOFTIRQ);
+       } else
+               irq_work_run_list(this_cpu_ptr(&lazy_list));
 }
 EXPORT_SYMBOL_GPL(irq_work_run);
 
@@ -179,8 +200,17 @@ void irq_work_tick(void)
 
        if (!llist_empty(raised) && !arch_irq_work_has_interrupt())
                irq_work_run_list(raised);
+
+       if (!IS_ENABLED(CONFIG_PREEMPT_RT_FULL))
+               irq_work_run_list(this_cpu_ptr(&lazy_list));
+}
+
+#if defined(CONFIG_IRQ_WORK) && defined(CONFIG_PREEMPT_RT_FULL)
+void irq_work_tick_soft(void)
+{
        irq_work_run_list(this_cpu_ptr(&lazy_list));
 }
+#endif
 
 /*
  * Synchronize against the irq_work @entry, ensures the entry is not
index ee1bc1b..ddef079 100644 (file)
@@ -136,6 +136,15 @@ KERNEL_ATTR_RO(vmcoreinfo);
 
 #endif /* CONFIG_KEXEC_CORE */
 
+#if defined(CONFIG_PREEMPT_RT_FULL)
+static ssize_t  realtime_show(struct kobject *kobj,
+                             struct kobj_attribute *attr, char *buf)
+{
+       return sprintf(buf, "%d\n", 1);
+}
+KERNEL_ATTR_RO(realtime);
+#endif
+
 /* whether file capabilities are enabled */
 static ssize_t fscaps_show(struct kobject *kobj,
                                  struct kobj_attribute *attr, char *buf)
@@ -225,6 +234,9 @@ static struct attribute * kernel_attrs[] = {
        &rcu_expedited_attr.attr,
        &rcu_normal_attr.attr,
 #endif
+#ifdef CONFIG_PREEMPT_RT_FULL
+       &realtime_attr.attr,
+#endif
        NULL
 };
 
index 6f88e35..6ff9e80 100644 (file)
@@ -2,7 +2,7 @@
 # and is generally not a function of system call inputs.
 KCOV_INSTRUMENT                := n
 
-obj-y += mutex.o semaphore.o rwsem.o percpu-rwsem.o
+obj-y += semaphore.o percpu-rwsem.o
 
 ifdef CONFIG_FUNCTION_TRACER
 CFLAGS_REMOVE_lockdep.o = $(CC_FLAGS_FTRACE)
@@ -11,7 +11,11 @@ CFLAGS_REMOVE_mutex-debug.o = $(CC_FLAGS_FTRACE)
 CFLAGS_REMOVE_rtmutex-debug.o = $(CC_FLAGS_FTRACE)
 endif
 
+ifneq ($(CONFIG_PREEMPT_RT_FULL),y)
+obj-y += mutex.o
 obj-$(CONFIG_DEBUG_MUTEXES) += mutex-debug.o
+endif
+obj-y += rwsem.o
 obj-$(CONFIG_LOCKDEP) += lockdep.o
 ifeq ($(CONFIG_PROC_FS),y)
 obj-$(CONFIG_LOCKDEP) += lockdep_proc.o
@@ -24,7 +28,10 @@ obj-$(CONFIG_RT_MUTEXES) += rtmutex.o
 obj-$(CONFIG_DEBUG_RT_MUTEXES) += rtmutex-debug.o
 obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock.o
 obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock_debug.o
+ifneq ($(CONFIG_PREEMPT_RT_FULL),y)
 obj-$(CONFIG_RWSEM_GENERIC_SPINLOCK) += rwsem-spinlock.o
 obj-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += rwsem-xadd.o
+endif
+obj-$(CONFIG_PREEMPT_RT_FULL) += rt.o rwsem-rt.o
 obj-$(CONFIG_QUEUED_RWLOCKS) += qrwlock.o
 obj-$(CONFIG_LOCK_TORTURE_TEST) += locktorture.o
index 9f56e3f..0069ccc 100644 (file)
@@ -658,6 +658,7 @@ look_up_lock_class(struct lockdep_map *lock, unsigned int subclass)
        struct lockdep_subclass_key *key;
        struct hlist_head *hash_head;
        struct lock_class *class;
+       bool is_static = false;
 
        if (unlikely(subclass >= MAX_LOCKDEP_SUBCLASSES)) {
                debug_locks_off();
@@ -671,10 +672,23 @@ look_up_lock_class(struct lockdep_map *lock, unsigned int subclass)
 
        /*
         * Static locks do not have their class-keys yet - for them the key
-        * is the lock object itself:
+        * is the lock object itself. If the lock is in the per cpu area,
+        * the canonical address of the lock (per cpu offset removed) is
+        * used.
         */
-       if (unlikely(!lock->key))
-               lock->key = (void *)lock;
+       if (unlikely(!lock->key)) {
+               unsigned long can_addr, addr = (unsigned long)lock;
+
+               if (__is_kernel_percpu_address(addr, &can_addr))
+                       lock->key = (void *)can_addr;
+               else if (__is_module_percpu_address(addr, &can_addr))
+                       lock->key = (void *)can_addr;
+               else if (static_obj(lock))
+                       lock->key = (void *)lock;
+               else
+                       return ERR_PTR(-EINVAL);
+               is_static = true;
+       }
 
        /*
         * NOTE: the class-key must be unique. For dynamic locks, a static
@@ -706,7 +720,7 @@ look_up_lock_class(struct lockdep_map *lock, unsigned int subclass)
                }
        }
 
-       return NULL;
+       return is_static || static_obj(lock->key) ? NULL : ERR_PTR(-EINVAL);
 }
 
 /*
@@ -724,19 +738,18 @@ register_lock_class(struct lockdep_map *lock, unsigned int subclass, int force)
        DEBUG_LOCKS_WARN_ON(!irqs_disabled());
 
        class = look_up_lock_class(lock, subclass);
-       if (likely(class))
+       if (likely(!IS_ERR_OR_NULL(class)))
                goto out_set_class_cache;
 
        /*
         * Debug-check: all keys must be persistent!
-        */
-       if (!static_obj(lock->key)) {
+        */
+       if (IS_ERR(class)) {
                debug_locks_off();
                printk("INFO: trying to register non-static key.\n");
                printk("the code is fine but needs lockdep annotation.\n");
                printk("turning off the locking correctness validator.\n");
                dump_stack();
-
                return NULL;
        }
 
@@ -3421,7 +3434,7 @@ static int match_held_lock(struct held_lock *hlock, struct lockdep_map *lock)
                 * Clearly if the lock hasn't been acquired _ever_, we're not
                 * holding it either, so report failure.
                 */
-               if (!class)
+               if (IS_ERR_OR_NULL(class))
                        return 0;
 
                /*
@@ -3703,6 +3716,7 @@ static void check_flags(unsigned long flags)
                }
        }
 
+#ifndef CONFIG_PREEMPT_RT_FULL
        /*
         * We dont accurately track softirq state in e.g.
         * hardirq contexts (such as on 4KSTACKS), so only
@@ -3717,6 +3731,7 @@ static void check_flags(unsigned long flags)
                        DEBUG_LOCKS_WARN_ON(!current->softirqs_enabled);
                }
        }
+#endif
 
        if (!debug_locks)
                print_irqtrace_events(current);
@@ -4173,7 +4188,7 @@ void lockdep_reset_lock(struct lockdep_map *lock)
                 * If the class exists we look it up and zap it:
                 */
                class = look_up_lock_class(lock, j);
-               if (class)
+               if (!IS_ERR_OR_NULL(class))
                        zap_class(class);
        }
        /*
index b0e41c3..afd3588 100644 (file)
@@ -26,7 +26,6 @@
 #include <linux/kthread.h>
 #include <linux/sched/rt.h>
 #include <linux/spinlock.h>
-#include <linux/rwlock.h>
 #include <linux/mutex.h>
 #include <linux/rwsem.h>
 #include <linux/smp.h>
index ce18259..2ad3a1e 100644 (file)
@@ -18,7 +18,7 @@ int __percpu_init_rwsem(struct percpu_rw_semaphore *sem,
        /* ->rw_sem represents the whole percpu_rw_semaphore for lockdep */
        rcu_sync_init(&sem->rss, RCU_SCHED_SYNC);
        __init_rwsem(&sem->rw_sem, name, rwsem_key);
-       init_waitqueue_head(&sem->writer);
+       init_swait_queue_head(&sem->writer);
        sem->readers_block = 0;
        return 0;
 }
@@ -103,7 +103,7 @@ void __percpu_up_read(struct percpu_rw_semaphore *sem)
        __this_cpu_dec(*sem->read_count);
 
        /* Prod writer to recheck readers_active */
-       wake_up(&sem->writer);
+       swake_up(&sem->writer);
 }
 EXPORT_SYMBOL_GPL(__percpu_up_read);
 
@@ -160,7 +160,7 @@ void percpu_down_write(struct percpu_rw_semaphore *sem)
         */
 
        /* Wait for all now active readers to complete. */
-       wait_event(sem->writer, readers_active_check(sem));
+       swait_event(sem->writer, readers_active_check(sem));
 }
 EXPORT_SYMBOL_GPL(percpu_down_write);
 
diff --git a/kernel/locking/rt.c b/kernel/locking/rt.c
new file mode 100644 (file)
index 0000000..6284e3b
--- /dev/null
@@ -0,0 +1,331 @@
+/*
+ * kernel/rt.c
+ *
+ * Real-Time Preemption Support
+ *
+ * started by Ingo Molnar:
+ *
+ *  Copyright (C) 2004-2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
+ *  Copyright (C) 2006, Timesys Corp., Thomas Gleixner <tglx@timesys.com>
+ *
+ * historic credit for proving that Linux spinlocks can be implemented via
+ * RT-aware mutexes goes to many people: The Pmutex project (Dirk Grambow
+ * and others) who prototyped it on 2.4 and did lots of comparative
+ * research and analysis; TimeSys, for proving that you can implement a
+ * fully preemptible kernel via the use of IRQ threading and mutexes;
+ * Bill Huey for persuasively arguing on lkml that the mutex model is the
+ * right one; and to MontaVista, who ported pmutexes to 2.6.
+ *
+ * This code is a from-scratch implementation and is not based on pmutexes,
+ * but the idea of converting spinlocks to mutexes is used here too.
+ *
+ * lock debugging, locking tree, deadlock detection:
+ *
+ *  Copyright (C) 2004, LynuxWorks, Inc., Igor Manyilov, Bill Huey
+ *  Released under the General Public License (GPL).
+ *
+ * Includes portions of the generic R/W semaphore implementation from:
+ *
+ *  Copyright (c) 2001   David Howells (dhowells@redhat.com).
+ *  - Derived partially from idea by Andrea Arcangeli <andrea@suse.de>
+ *  - Derived also from comments by Linus
+ *
+ * Pending ownership of locks and ownership stealing:
+ *
+ *  Copyright (C) 2005, Kihon Technologies Inc., Steven Rostedt
+ *
+ *   (also by Steven Rostedt)
+ *    - Converted single pi_lock to individual task locks.
+ *
+ * By Esben Nielsen:
+ *    Doing priority inheritance with help of the scheduler.
+ *
+ *  Copyright (C) 2006, Timesys Corp., Thomas Gleixner <tglx@timesys.com>
+ *  - major rework based on Esben Nielsens initial patch
+ *  - replaced thread_info references by task_struct refs
+ *  - removed task->pending_owner dependency
+ *  - BKL drop/reacquire for semaphore style locks to avoid deadlocks
+ *    in the scheduler return path as discussed with Steven Rostedt
+ *
+ *  Copyright (C) 2006, Kihon Technologies Inc.
+ *    Steven Rostedt <rostedt@goodmis.org>
+ *  - debugged and patched Thomas Gleixner's rework.
+ *  - added back the cmpxchg to the rework.
+ *  - turned atomic require back on for SMP.
+ */
+
+#include <linux/spinlock.h>
+#include <linux/rtmutex.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/kallsyms.h>
+#include <linux/syscalls.h>
+#include <linux/interrupt.h>
+#include <linux/plist.h>
+#include <linux/fs.h>
+#include <linux/futex.h>
+#include <linux/hrtimer.h>
+
+#include "rtmutex_common.h"
+
+/*
+ * struct mutex functions
+ */
+void __mutex_do_init(struct mutex *mutex, const char *name,
+                    struct lock_class_key *key)
+{
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+       /*
+        * Make sure we are not reinitializing a held lock:
+        */
+       debug_check_no_locks_freed((void *)mutex, sizeof(*mutex));
+       lockdep_init_map(&mutex->dep_map, name, key, 0);
+#endif
+       mutex->lock.save_state = 0;
+}
+EXPORT_SYMBOL(__mutex_do_init);
+
+void __lockfunc _mutex_lock(struct mutex *lock)
+{
+       mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+       rt_mutex_lock(&lock->lock);
+}
+EXPORT_SYMBOL(_mutex_lock);
+
+int __lockfunc _mutex_lock_interruptible(struct mutex *lock)
+{
+       int ret;
+
+       mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+       ret = rt_mutex_lock_interruptible(&lock->lock);
+       if (ret)
+               mutex_release(&lock->dep_map, 1, _RET_IP_);
+       return ret;
+}
+EXPORT_SYMBOL(_mutex_lock_interruptible);
+
+int __lockfunc _mutex_lock_killable(struct mutex *lock)
+{
+       int ret;
+
+       mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+       ret = rt_mutex_lock_killable(&lock->lock);
+       if (ret)
+               mutex_release(&lock->dep_map, 1, _RET_IP_);
+       return ret;
+}
+EXPORT_SYMBOL(_mutex_lock_killable);
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+void __lockfunc _mutex_lock_nested(struct mutex *lock, int subclass)
+{
+       mutex_acquire_nest(&lock->dep_map, subclass, 0, NULL, _RET_IP_);
+       rt_mutex_lock(&lock->lock);
+}
+EXPORT_SYMBOL(_mutex_lock_nested);
+
+void __lockfunc _mutex_lock_nest_lock(struct mutex *lock, struct lockdep_map *nest)
+{
+       mutex_acquire_nest(&lock->dep_map, 0, 0, nest, _RET_IP_);
+       rt_mutex_lock(&lock->lock);
+}
+EXPORT_SYMBOL(_mutex_lock_nest_lock);
+
+int __lockfunc _mutex_lock_interruptible_nested(struct mutex *lock, int subclass)
+{
+       int ret;
+
+       mutex_acquire_nest(&lock->dep_map, subclass, 0, NULL, _RET_IP_);
+       ret = rt_mutex_lock_interruptible(&lock->lock);
+       if (ret)
+               mutex_release(&lock->dep_map, 1, _RET_IP_);
+       return ret;
+}
+EXPORT_SYMBOL(_mutex_lock_interruptible_nested);
+
+int __lockfunc _mutex_lock_killable_nested(struct mutex *lock, int subclass)
+{
+       int ret;
+
+       mutex_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
+       ret = rt_mutex_lock_killable(&lock->lock);
+       if (ret)
+               mutex_release(&lock->dep_map, 1, _RET_IP_);
+       return ret;
+}
+EXPORT_SYMBOL(_mutex_lock_killable_nested);
+#endif
+
+int __lockfunc _mutex_trylock(struct mutex *lock)
+{
+       int ret = rt_mutex_trylock(&lock->lock);
+
+       if (ret)
+               mutex_acquire(&lock->dep_map, 0, 1, _RET_IP_);
+
+       return ret;
+}
+EXPORT_SYMBOL(_mutex_trylock);
+
+void __lockfunc _mutex_unlock(struct mutex *lock)
+{
+       mutex_release(&lock->dep_map, 1, _RET_IP_);
+       rt_mutex_unlock(&lock->lock);
+}
+EXPORT_SYMBOL(_mutex_unlock);
+
+/*
+ * rwlock_t functions
+ */
+int __lockfunc rt_write_trylock(rwlock_t *rwlock)
+{
+       int ret;
+
+       migrate_disable();
+       ret = rt_mutex_trylock(&rwlock->lock);
+       if (ret)
+               rwlock_acquire(&rwlock->dep_map, 0, 1, _RET_IP_);
+       else
+               migrate_enable();
+
+       return ret;
+}
+EXPORT_SYMBOL(rt_write_trylock);
+
+int __lockfunc rt_write_trylock_irqsave(rwlock_t *rwlock, unsigned long *flags)
+{
+       int ret;
+
+       *flags = 0;
+       ret = rt_write_trylock(rwlock);
+       return ret;
+}
+EXPORT_SYMBOL(rt_write_trylock_irqsave);
+
+int __lockfunc rt_read_trylock(rwlock_t *rwlock)
+{
+       struct rt_mutex *lock = &rwlock->lock;
+       int ret = 1;
+
+       /*
+        * recursive read locks succeed when current owns the lock,
+        * but not when read_depth == 0 which means that the lock is
+        * write locked.
+        */
+       if (rt_mutex_owner(lock) != current) {
+               migrate_disable();
+               ret = rt_mutex_trylock(lock);
+               if (ret)
+                       rwlock_acquire(&rwlock->dep_map, 0, 1, _RET_IP_);
+               else
+                       migrate_enable();
+
+       } else if (!rwlock->read_depth) {
+               ret = 0;
+       }
+
+       if (ret)
+               rwlock->read_depth++;
+
+       return ret;
+}
+EXPORT_SYMBOL(rt_read_trylock);
+
+void __lockfunc rt_write_lock(rwlock_t *rwlock)
+{
+       rwlock_acquire(&rwlock->dep_map, 0, 0, _RET_IP_);
+       __rt_spin_lock(&rwlock->lock);
+}
+EXPORT_SYMBOL(rt_write_lock);
+
+void __lockfunc rt_read_lock(rwlock_t *rwlock)
+{
+       struct rt_mutex *lock = &rwlock->lock;
+
+
+       /*
+        * recursive read locks succeed when current owns the lock
+        */
+       if (rt_mutex_owner(lock) != current) {
+               rwlock_acquire(&rwlock->dep_map, 0, 0, _RET_IP_);
+               __rt_spin_lock(lock);
+       }
+       rwlock->read_depth++;
+}
+
+EXPORT_SYMBOL(rt_read_lock);
+
+void __lockfunc rt_write_unlock(rwlock_t *rwlock)
+{
+       /* NOTE: we always pass in '1' for nested, for simplicity */
+       rwlock_release(&rwlock->dep_map, 1, _RET_IP_);
+       __rt_spin_unlock(&rwlock->lock);
+       migrate_enable();
+}
+EXPORT_SYMBOL(rt_write_unlock);
+
+void __lockfunc rt_read_unlock(rwlock_t *rwlock)
+{
+       /* Release the lock only when read_depth is down to 0 */
+       if (--rwlock->read_depth == 0) {
+               rwlock_release(&rwlock->dep_map, 1, _RET_IP_);
+               __rt_spin_unlock(&rwlock->lock);
+               migrate_enable();
+       }
+}
+EXPORT_SYMBOL(rt_read_unlock);
+
+unsigned long __lockfunc rt_write_lock_irqsave(rwlock_t *rwlock)
+{
+       rt_write_lock(rwlock);
+
+       return 0;
+}
+EXPORT_SYMBOL(rt_write_lock_irqsave);
+
+unsigned long __lockfunc rt_read_lock_irqsave(rwlock_t *rwlock)
+{
+       rt_read_lock(rwlock);
+
+       return 0;
+}
+EXPORT_SYMBOL(rt_read_lock_irqsave);
+
+void __rt_rwlock_init(rwlock_t *rwlock, char *name, struct lock_class_key *key)
+{
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+       /*
+        * Make sure we are not reinitializing a held lock:
+        */
+       debug_check_no_locks_freed((void *)rwlock, sizeof(*rwlock));
+       lockdep_init_map(&rwlock->dep_map, name, key, 0);
+#endif
+       rwlock->lock.save_state = 1;
+       rwlock->read_depth = 0;
+}
+EXPORT_SYMBOL(__rt_rwlock_init);
+
+/**
+ * atomic_dec_and_mutex_lock - return holding mutex if we dec to 0
+ * @cnt: the atomic which we are to dec
+ * @lock: the mutex to return holding if we dec to 0
+ *
+ * return true and hold lock if we dec to 0, return false otherwise
+ */
+int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock)
+{
+       /* dec if we can't possibly hit 0 */
+       if (atomic_add_unless(cnt, -1, 1))
+               return 0;
+       /* we might hit 0, so take the lock */
+       mutex_lock(lock);
+       if (!atomic_dec_and_test(cnt)) {
+               /* when we actually did the dec, we didn't hit 0 */
+               mutex_unlock(lock);
+               return 0;
+       }
+       /* we hit 0, and we hold the lock */
+       return 1;
+}
+EXPORT_SYMBOL(atomic_dec_and_mutex_lock);
index 62b6cee..0613c4b 100644 (file)
@@ -173,12 +173,3 @@ void debug_rt_mutex_init(struct rt_mutex *lock, const char *name)
        lock->name = name;
 }
 
-void
-rt_mutex_deadlock_account_lock(struct rt_mutex *lock, struct task_struct *task)
-{
-}
-
-void rt_mutex_deadlock_account_unlock(struct task_struct *task)
-{
-}
-
index d0519c3..b585af9 100644 (file)
@@ -9,9 +9,6 @@
  * This file contains macros used solely by rtmutex.c. Debug version.
  */
 
-extern void
-rt_mutex_deadlock_account_lock(struct rt_mutex *lock, struct task_struct *task);
-extern void rt_mutex_deadlock_account_unlock(struct task_struct *task);
 extern void debug_rt_mutex_init_waiter(struct rt_mutex_waiter *waiter);
 extern void debug_rt_mutex_free_waiter(struct rt_mutex_waiter *waiter);
 extern void debug_rt_mutex_init(struct rt_mutex *lock, const char *name);
index 7615e77..af10410 100644 (file)
@@ -7,6 +7,11 @@
  *  Copyright (C) 2005-2006 Timesys Corp., Thomas Gleixner <tglx@timesys.com>
  *  Copyright (C) 2005 Kihon Technologies Inc., Steven Rostedt
  *  Copyright (C) 2006 Esben Nielsen
+ *  Adaptive Spinlocks:
+ *  Copyright (C) 2008 Novell, Inc., Gregory Haskins, Sven Dietrich,
+ *                                  and Peter Morreale,
+ * Adaptive Spinlocks simplification:
+ *  Copyright (C) 2008 Red Hat, Inc., Steven Rostedt <srostedt@redhat.com>
  *
  *  See Documentation/locking/rt-mutex-design.txt for details.
  */
@@ -16,6 +21,8 @@
 #include <linux/sched/rt.h>
 #include <linux/sched/deadline.h>
 #include <linux/timer.h>
+#include <linux/ww_mutex.h>
+#include <linux/blkdev.h>
 
 #include "rtmutex_common.h"
 
@@ -133,6 +140,12 @@ static void fixup_rt_mutex_waiters(struct rt_mutex *lock)
                WRITE_ONCE(*p, owner & ~RT_MUTEX_HAS_WAITERS);
 }
 
+static int rt_mutex_real_waiter(struct rt_mutex_waiter *waiter)
+{
+       return waiter && waiter != PI_WAKEUP_INPROGRESS &&
+               waiter != PI_REQUEUE_INPROGRESS;
+}
+
 /*
  * We can speed up the acquire/release, if there's no debugging state to be
  * set up.
@@ -222,6 +235,12 @@ static inline bool unlock_rt_mutex_safe(struct rt_mutex *lock,
 }
 #endif
 
+/*
+ * Only use with rt_mutex_waiter_{less,equal}()
+ */
+#define task_to_waiter(p) &(struct rt_mutex_waiter) \
+       { .prio = (p)->prio, .deadline = (p)->dl.deadline, .task = (p) }
+
 static inline int
 rt_mutex_waiter_less(struct rt_mutex_waiter *left,
                     struct rt_mutex_waiter *right)
@@ -241,6 +260,46 @@ rt_mutex_waiter_less(struct rt_mutex_waiter *left,
        return 0;
 }
 
+static inline int
+rt_mutex_waiter_equal(struct rt_mutex_waiter *left,
+                     struct rt_mutex_waiter *right)
+{
+       if (left->prio != right->prio)
+               return 0;
+
+       /*
+        * If both waiters have dl_prio(), we check the deadlines of the
+        * associated tasks.
+        * If left waiter has a dl_prio(), and we didn't return 0 above,
+        * then right waiter has a dl_prio() too.
+        */
+       if (dl_prio(left->prio))
+               return left->deadline == right->deadline;
+
+       return 1;
+}
+
+#define STEAL_NORMAL  0
+#define STEAL_LATERAL 1
+
+static inline int
+rt_mutex_steal(struct rt_mutex *lock, struct rt_mutex_waiter *waiter, int mode)
+{
+       struct rt_mutex_waiter *top_waiter = rt_mutex_top_waiter(lock);
+
+       if (waiter == top_waiter || rt_mutex_waiter_less(waiter, top_waiter))
+               return 1;
+
+       /*
+        * Note that RT tasks are excluded from lateral-steals
+        * to prevent the introduction of an unbounded latency.
+        */
+       if (mode == STEAL_NORMAL || rt_task(waiter->task))
+               return 0;
+
+       return rt_mutex_waiter_equal(waiter, top_waiter);
+}
+
 static void
 rt_mutex_enqueue(struct rt_mutex *lock, struct rt_mutex_waiter *waiter)
 {
@@ -319,72 +378,16 @@ rt_mutex_dequeue_pi(struct task_struct *task, struct rt_mutex_waiter *waiter)
        RB_CLEAR_NODE(&waiter->pi_tree_entry);
 }
 
-/*
- * Calculate task priority from the waiter tree priority
- *
- * Return task->normal_prio when the waiter tree is empty or when
- * the waiter is not allowed to do priority boosting
- */
-int rt_mutex_getprio(struct task_struct *task)
-{
-       if (likely(!task_has_pi_waiters(task)))
-               return task->normal_prio;
-
-       return min(task_top_pi_waiter(task)->prio,
-                  task->normal_prio);
-}
-
-struct task_struct *rt_mutex_get_top_task(struct task_struct *task)
-{
-       if (likely(!task_has_pi_waiters(task)))
-               return NULL;
-
-       return task_top_pi_waiter(task)->task;
-}
-
-/*
- * Called by sched_setscheduler() to get the priority which will be
- * effective after the change.
- */
-int rt_mutex_get_effective_prio(struct task_struct *task, int newprio)
-{
-       if (!task_has_pi_waiters(task))
-               return newprio;
-
-       if (task_top_pi_waiter(task)->task->prio <= newprio)
-               return task_top_pi_waiter(task)->task->prio;
-       return newprio;
-}
-
-/*
- * Adjust the priority of a task, after its pi_waiters got modified.
- *
- * This can be both boosting and unboosting. task->pi_lock must be held.
- */
-static void __rt_mutex_adjust_prio(struct task_struct *task)
+static void rt_mutex_adjust_prio(struct task_struct *p)
 {
-       int prio = rt_mutex_getprio(task);
+       struct task_struct *pi_task = NULL;
 
-       if (task->prio != prio || dl_prio(prio))
-               rt_mutex_setprio(task, prio);
-}
+       lockdep_assert_held(&p->pi_lock);
 
-/*
- * Adjust task priority (undo boosting). Called from the exit path of
- * rt_mutex_slowunlock() and rt_mutex_slowlock().
- *
- * (Note: We do this outside of the protection of lock->wait_lock to
- * allow the lock to be taken while or before we readjust the priority
- * of task. We do not use the spin_xx_mutex() variants here as we are
- * outside of the debug path.)
- */
-void rt_mutex_adjust_prio(struct task_struct *task)
-{
-       unsigned long flags;
+       if (task_has_pi_waiters(p))
+               pi_task = task_top_pi_waiter(p)->task;
 
-       raw_spin_lock_irqsave(&task->pi_lock, flags);
-       __rt_mutex_adjust_prio(task);
-       raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+       rt_mutex_setprio(p, pi_task);
 }
 
 /*
@@ -413,6 +416,14 @@ static bool rt_mutex_cond_detect_deadlock(struct rt_mutex_waiter *waiter,
        return debug_rt_mutex_detect_deadlock(waiter, chwalk);
 }
 
+static void rt_mutex_wake_waiter(struct rt_mutex_waiter *waiter)
+{
+       if (waiter->savestate)
+               wake_up_lock_sleeper(waiter->task);
+       else
+               wake_up_process(waiter->task);
+}
+
 /*
  * Max number of times we'll walk the boosting chain:
  */
@@ -420,7 +431,8 @@ int max_lock_depth = 1024;
 
 static inline struct rt_mutex *task_blocked_on_lock(struct task_struct *p)
 {
-       return p->pi_blocked_on ? p->pi_blocked_on->lock : NULL;
+       return rt_mutex_real_waiter(p->pi_blocked_on) ?
+               p->pi_blocked_on->lock : NULL;
 }
 
 /*
@@ -556,7 +568,7 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
         * reached or the state of the chain has changed while we
         * dropped the locks.
         */
-       if (!waiter)
+       if (!rt_mutex_real_waiter(waiter))
                goto out_unlock_pi;
 
        /*
@@ -607,7 +619,7 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
         * enabled we continue, but stop the requeueing in the chain
         * walk.
         */
-       if (waiter->prio == task->prio) {
+       if (rt_mutex_waiter_equal(waiter, task_to_waiter(task))) {
                if (!detect_deadlock)
                        goto out_unlock_pi;
                else
@@ -737,13 +749,16 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
         * follow here. This is the end of the chain we are walking.
         */
        if (!rt_mutex_owner(lock)) {
+               struct rt_mutex_waiter *lock_top_waiter;
+
                /*
                 * If the requeue [7] above changed the top waiter,
                 * then we need to wake the new top waiter up to try
                 * to get the lock.
                 */
-               if (prerequeue_top_waiter != rt_mutex_top_waiter(lock))
-                       wake_up_process(rt_mutex_top_waiter(lock)->task);
+               lock_top_waiter = rt_mutex_top_waiter(lock);
+               if (prerequeue_top_waiter != lock_top_waiter)
+                       rt_mutex_wake_waiter(lock_top_waiter);
                raw_spin_unlock_irq(&lock->wait_lock);
                return 0;
        }
@@ -763,7 +778,7 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
                 */
                rt_mutex_dequeue_pi(task, prerequeue_top_waiter);
                rt_mutex_enqueue_pi(task, waiter);
-               __rt_mutex_adjust_prio(task);
+               rt_mutex_adjust_prio(task);
 
        } else if (prerequeue_top_waiter == waiter) {
                /*
@@ -779,7 +794,7 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
                rt_mutex_dequeue_pi(task, waiter);
                waiter = rt_mutex_top_waiter(lock);
                rt_mutex_enqueue_pi(task, waiter);
-               __rt_mutex_adjust_prio(task);
+               rt_mutex_adjust_prio(task);
        } else {
                /*
                 * Nothing changed. No need to do any priority
@@ -836,6 +851,7 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
        return ret;
 }
 
+
 /*
  * Try to take an rt-mutex
  *
@@ -845,9 +861,11 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
  * @task:   The task which wants to acquire the lock
  * @waiter: The waiter that is queued to the lock's wait tree if the
  *         callsite called task_blocked_on_lock(), otherwise NULL
+ * @mode:   Lock steal mode (STEAL_NORMAL, STEAL_LATERAL)
  */
-static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
-                               struct rt_mutex_waiter *waiter)
+static int __try_to_take_rt_mutex(struct rt_mutex *lock,
+                                 struct task_struct *task,
+                                 struct rt_mutex_waiter *waiter, int mode)
 {
        lockdep_assert_held(&lock->wait_lock);
 
@@ -883,12 +901,11 @@ static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
         */
        if (waiter) {
                /*
-                * If waiter is not the highest priority waiter of
-                * @lock, give up.
+                * If waiter is not the highest priority waiter of @lock,
+                * or its peer when lateral steal is allowed, give up.
                 */
-               if (waiter != rt_mutex_top_waiter(lock))
+               if (!rt_mutex_steal(lock, waiter, mode))
                        return 0;
-
                /*
                 * We can acquire the lock. Remove the waiter from the
                 * lock waiters tree.
@@ -906,13 +923,12 @@ static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
                 */
                if (rt_mutex_has_waiters(lock)) {
                        /*
-                        * If @task->prio is greater than or equal to
-                        * the top waiter priority (kernel view),
-                        * @task lost.
+                        * If @task->prio is greater than the top waiter
+                        * priority (kernel view), or equal to it when a
+                        * lateral steal is forbidden, @task lost.
                         */
-                       if (task->prio >= rt_mutex_top_waiter(lock)->prio)
+                       if (!rt_mutex_steal(lock, task_to_waiter(task), mode))
                                return 0;
-
                        /*
                         * The current top waiter stays enqueued. We
                         * don't have to change anything in the lock
@@ -956,180 +972,587 @@ takeit:
         */
        rt_mutex_set_owner(lock, task);
 
-       rt_mutex_deadlock_account_lock(lock, task);
-
        return 1;
 }
 
+#ifdef CONFIG_PREEMPT_RT_FULL
 /*
- * Task blocks on lock.
- *
- * Prepare waiter and propagate pi chain
- *
- * This must be called with lock->wait_lock held and interrupts disabled
+ * preemptible spin_lock functions:
+ */
+static inline void rt_spin_lock_fastlock(struct rt_mutex *lock,
+                                        void  (*slowfn)(struct rt_mutex *lock,
+                                                        bool mg_off),
+                                        bool do_mig_dis)
+{
+       might_sleep_no_state_check();
+
+       if (do_mig_dis)
+               migrate_disable();
+
+       if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current)))
+               return;
+       else
+               slowfn(lock, do_mig_dis);
+}
+
+static inline void rt_spin_lock_fastunlock(struct rt_mutex *lock,
+                                          void  (*slowfn)(struct rt_mutex *lock))
+{
+       if (likely(rt_mutex_cmpxchg_release(lock, current, NULL)))
+               return;
+       else
+               slowfn(lock);
+}
+#ifdef CONFIG_SMP
+/*
+ * Note that owner is a speculative pointer and dereferencing relies
+ * on rcu_read_lock() and the check against the lock owner.
  */
+static int adaptive_wait(struct rt_mutex *lock,
+                        struct task_struct *owner)
+{
+       int res = 0;
+
+       rcu_read_lock();
+       for (;;) {
+               if (owner != rt_mutex_owner(lock))
+                       break;
+               /*
+                * Ensure that owner->on_cpu is dereferenced _after_
+                * checking the above to be valid.
+                */
+               barrier();
+               if (!owner->on_cpu) {
+                       res = 1;
+                       break;
+               }
+               cpu_relax();
+       }
+       rcu_read_unlock();
+       return res;
+}
+#else
+static int adaptive_wait(struct rt_mutex *lock,
+                        struct task_struct *orig_owner)
+{
+       return 1;
+}
+#endif
+
 static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
                                   struct rt_mutex_waiter *waiter,
                                   struct task_struct *task,
-                                  enum rtmutex_chainwalk chwalk)
+                                  enum rtmutex_chainwalk chwalk);
+/*
+ * Slow path lock function spin_lock style: this variant is very
+ * careful not to miss any non-lock wakeups.
+ *
+ * We store the current state under p->pi_lock in p->saved_state and
+ * the try_to_wake_up() code handles this accordingly.
+ */
+static void  noinline __sched rt_spin_lock_slowlock(struct rt_mutex *lock,
+                                                   bool mg_off)
 {
-       struct task_struct *owner = rt_mutex_owner(lock);
-       struct rt_mutex_waiter *top_waiter = waiter;
-       struct rt_mutex *next_lock;
-       int chain_walk = 0, res;
+       struct task_struct *lock_owner, *self = current;
+       struct rt_mutex_waiter waiter, *top_waiter;
+       unsigned long flags;
+       int ret;
 
-       lockdep_assert_held(&lock->wait_lock);
+       rt_mutex_init_waiter(&waiter, true);
+
+       raw_spin_lock_irqsave(&lock->wait_lock, flags);
+
+       if (__try_to_take_rt_mutex(lock, self, NULL, STEAL_LATERAL)) {
+               raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
+               return;
+       }
+
+       BUG_ON(rt_mutex_owner(lock) == self);
 
        /*
-        * Early deadlock detection. We really don't want the task to
-        * enqueue on itself just to untangle the mess later. It's not
-        * only an optimization. We drop the locks, so another waiter
-        * can come in before the chain walk detects the deadlock. So
-        * the other will detect the deadlock and return -EDEADLOCK,
-        * which is wrong, as the other waiter is not in a deadlock
-        * situation.
+        * We save whatever state the task is in and we'll restore it
+        * after acquiring the lock taking real wakeups into account
+        * as well. We are serialized via pi_lock against wakeups. See
+        * try_to_wake_up().
         */
-       if (owner == task)
-               return -EDEADLK;
+       raw_spin_lock(&self->pi_lock);
+       self->saved_state = self->state;
+       __set_current_state_no_track(TASK_UNINTERRUPTIBLE);
+       raw_spin_unlock(&self->pi_lock);
 
-       raw_spin_lock(&task->pi_lock);
-       __rt_mutex_adjust_prio(task);
-       waiter->task = task;
-       waiter->lock = lock;
-       waiter->prio = task->prio;
-       waiter->deadline = task->dl.deadline;
+       ret = task_blocks_on_rt_mutex(lock, &waiter, self, RT_MUTEX_MIN_CHAINWALK);
+       BUG_ON(ret);
+
+       for (;;) {
+               /* Try to acquire the lock again. */
+               if (__try_to_take_rt_mutex(lock, self, &waiter, STEAL_LATERAL))
+                       break;
 
-       /* Get the top priority waiter on the lock */
-       if (rt_mutex_has_waiters(lock))
                top_waiter = rt_mutex_top_waiter(lock);
-       rt_mutex_enqueue(lock, waiter);
+               lock_owner = rt_mutex_owner(lock);
 
-       task->pi_blocked_on = waiter;
+               raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
 
-       raw_spin_unlock(&task->pi_lock);
+               debug_rt_mutex_print_deadlock(&waiter);
 
-       if (!owner)
-               return 0;
+               if (top_waiter != &waiter || adaptive_wait(lock, lock_owner)) {
+                       if (mg_off)
+                               migrate_enable();
+                       schedule();
+                       if (mg_off)
+                               migrate_disable();
+               }
 
-       raw_spin_lock(&owner->pi_lock);
-       if (waiter == rt_mutex_top_waiter(lock)) {
-               rt_mutex_dequeue_pi(owner, top_waiter);
-               rt_mutex_enqueue_pi(owner, waiter);
+               raw_spin_lock_irqsave(&lock->wait_lock, flags);
 
-               __rt_mutex_adjust_prio(owner);
-               if (owner->pi_blocked_on)
-                       chain_walk = 1;
-       } else if (rt_mutex_cond_detect_deadlock(waiter, chwalk)) {
-               chain_walk = 1;
+               raw_spin_lock(&self->pi_lock);
+               __set_current_state_no_track(TASK_UNINTERRUPTIBLE);
+               raw_spin_unlock(&self->pi_lock);
        }
 
-       /* Store the lock on which owner is blocked or NULL */
-       next_lock = task_blocked_on_lock(owner);
-
-       raw_spin_unlock(&owner->pi_lock);
        /*
-        * Even if full deadlock detection is on, if the owner is not
-        * blocked itself, we can avoid finding this out in the chain
-        * walk.
+        * Restore the task state to current->saved_state. We set it
+        * to the original state above and the try_to_wake_up() code
+        * has possibly updated it when a real (non-rtmutex) wakeup
+        * happened while we were blocked. Clear saved_state so
+        * try_to_wakeup() does not get confused.
         */
-       if (!chain_walk || !next_lock)
-               return 0;
+       raw_spin_lock(&self->pi_lock);
+       __set_current_state_no_track(self->saved_state);
+       self->saved_state = TASK_RUNNING;
+       raw_spin_unlock(&self->pi_lock);
 
        /*
-        * The owner can't disappear while holding a lock,
-        * so the owner struct is protected by wait_lock.
-        * Gets dropped in rt_mutex_adjust_prio_chain()!
+        * try_to_take_rt_mutex() sets the waiter bit
+        * unconditionally. We might have to fix that up:
         */
-       get_task_struct(owner);
-
-       raw_spin_unlock_irq(&lock->wait_lock);
+       fixup_rt_mutex_waiters(lock);
 
-       res = rt_mutex_adjust_prio_chain(owner, chwalk, lock,
-                                        next_lock, waiter, task);
+       BUG_ON(rt_mutex_has_waiters(lock) && &waiter == rt_mutex_top_waiter(lock));
+       BUG_ON(!RB_EMPTY_NODE(&waiter.tree_entry));
 
-       raw_spin_lock_irq(&lock->wait_lock);
+       raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
 
-       return res;
+       debug_rt_mutex_free_waiter(&waiter);
 }
 
+static bool __sched __rt_mutex_unlock_common(struct rt_mutex *lock,
+                                            struct wake_q_head *wake_q,
+                                            struct wake_q_head *wq_sleeper);
 /*
- * Remove the top waiter from the current tasks pi waiter tree and
- * queue it up.
- *
- * Called with lock->wait_lock held and interrupts disabled.
+ * Slow path to release a rt_mutex spin_lock style
  */
-static void mark_wakeup_next_waiter(struct wake_q_head *wake_q,
-                                   struct rt_mutex *lock)
+static void  noinline __sched rt_spin_lock_slowunlock(struct rt_mutex *lock)
 {
-       struct rt_mutex_waiter *waiter;
-
-       raw_spin_lock(&current->pi_lock);
+       unsigned long flags;
+       WAKE_Q(wake_q);
+       WAKE_Q(wake_sleeper_q);
+       bool postunlock;
 
-       waiter = rt_mutex_top_waiter(lock);
+       raw_spin_lock_irqsave(&lock->wait_lock, flags);
+       postunlock = __rt_mutex_unlock_common(lock, &wake_q, &wake_sleeper_q);
+       raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
 
-       /*
-        * Remove it from current->pi_waiters. We do not adjust a
-        * possible priority boost right now. We execute wakeup in the
-        * boosted mode and go back to normal after releasing
-        * lock->wait_lock.
-        */
-       rt_mutex_dequeue_pi(current, waiter);
+       if (postunlock)
+               rt_mutex_postunlock(&wake_q, &wake_sleeper_q);
+}
 
-       /*
-        * As we are waking up the top waiter, and the waiter stays
-        * queued on the lock until it gets the lock, this lock
-        * obviously has waiters. Just set the bit here and this has
-        * the added benefit of forcing all new tasks into the
-        * slow path making sure no task of lower priority than
-        * the top waiter can steal this lock.
-        */
-       lock->owner = (void *) RT_MUTEX_HAS_WAITERS;
+void __lockfunc rt_spin_lock__no_mg(spinlock_t *lock)
+{
+       rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock, false);
+       spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+}
+EXPORT_SYMBOL(rt_spin_lock__no_mg);
 
-       raw_spin_unlock(&current->pi_lock);
+void __lockfunc rt_spin_lock(spinlock_t *lock)
+{
+       rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock, true);
+       spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+}
+EXPORT_SYMBOL(rt_spin_lock);
 
-       wake_q_add(wake_q, waiter->task);
+void __lockfunc __rt_spin_lock(struct rt_mutex *lock)
+{
+       rt_spin_lock_fastlock(lock, rt_spin_lock_slowlock, true);
 }
+EXPORT_SYMBOL(__rt_spin_lock);
 
-/*
- * Remove a waiter from a lock and give up
- *
- * Must be called with lock->wait_lock held and interrupts disabled. I must
- * have just failed to try_to_take_rt_mutex().
- */
-static void remove_waiter(struct rt_mutex *lock,
-                         struct rt_mutex_waiter *waiter)
+void __lockfunc __rt_spin_lock__no_mg(struct rt_mutex *lock)
 {
-       bool is_top_waiter = (waiter == rt_mutex_top_waiter(lock));
-       struct task_struct *owner = rt_mutex_owner(lock);
-       struct rt_mutex *next_lock;
+       rt_spin_lock_fastlock(lock, rt_spin_lock_slowlock, false);
+}
+EXPORT_SYMBOL(__rt_spin_lock__no_mg);
 
-       lockdep_assert_held(&lock->wait_lock);
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+void __lockfunc rt_spin_lock_nested(spinlock_t *lock, int subclass)
+{
+       spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
+       rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock, true);
+}
+EXPORT_SYMBOL(rt_spin_lock_nested);
+#endif
 
-       raw_spin_lock(&current->pi_lock);
-       rt_mutex_dequeue(lock, waiter);
-       current->pi_blocked_on = NULL;
-       raw_spin_unlock(&current->pi_lock);
+void __lockfunc rt_spin_unlock__no_mg(spinlock_t *lock)
+{
+       /* NOTE: we always pass in '1' for nested, for simplicity */
+       spin_release(&lock->dep_map, 1, _RET_IP_);
+       rt_spin_lock_fastunlock(&lock->lock, rt_spin_lock_slowunlock);
+}
+EXPORT_SYMBOL(rt_spin_unlock__no_mg);
 
-       /*
-        * Only update priority if the waiter was the highest priority
-        * waiter of the lock and there is an owner to update.
-        */
-       if (!owner || !is_top_waiter)
-               return;
+void __lockfunc rt_spin_unlock(spinlock_t *lock)
+{
+       /* NOTE: we always pass in '1' for nested, for simplicity */
+       spin_release(&lock->dep_map, 1, _RET_IP_);
+       rt_spin_lock_fastunlock(&lock->lock, rt_spin_lock_slowunlock);
+       migrate_enable();
+}
+EXPORT_SYMBOL(rt_spin_unlock);
 
-       raw_spin_lock(&owner->pi_lock);
+void __lockfunc __rt_spin_unlock(struct rt_mutex *lock)
+{
+       rt_spin_lock_fastunlock(lock, rt_spin_lock_slowunlock);
+}
+EXPORT_SYMBOL(__rt_spin_unlock);
 
-       rt_mutex_dequeue_pi(owner, waiter);
+/*
+ * Wait for the lock to get unlocked: instead of polling for an unlock
+ * (like raw spinlocks do), we lock and unlock, to force the kernel to
+ * schedule if there's contention:
+ */
+void __lockfunc rt_spin_unlock_wait(spinlock_t *lock)
+{
+       spin_lock(lock);
+       spin_unlock(lock);
+}
+EXPORT_SYMBOL(rt_spin_unlock_wait);
 
-       if (rt_mutex_has_waiters(lock))
-               rt_mutex_enqueue_pi(owner, rt_mutex_top_waiter(lock));
+int __lockfunc rt_spin_trylock__no_mg(spinlock_t *lock)
+{
+       int ret;
 
-       __rt_mutex_adjust_prio(owner);
+       ret = rt_mutex_trylock(&lock->lock);
+       if (ret)
+               spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
+       return ret;
+}
+EXPORT_SYMBOL(rt_spin_trylock__no_mg);
+
+int __lockfunc rt_spin_trylock(spinlock_t *lock)
+{
+       int ret;
+
+       migrate_disable();
+       ret = rt_mutex_trylock(&lock->lock);
+       if (ret)
+               spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
+       else
+               migrate_enable();
+       return ret;
+}
+EXPORT_SYMBOL(rt_spin_trylock);
+
+int __lockfunc rt_spin_trylock_bh(spinlock_t *lock)
+{
+       int ret;
+
+       local_bh_disable();
+       ret = rt_mutex_trylock(&lock->lock);
+       if (ret) {
+               migrate_disable();
+               spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
+       } else
+               local_bh_enable();
+       return ret;
+}
+EXPORT_SYMBOL(rt_spin_trylock_bh);
+
+int __lockfunc rt_spin_trylock_irqsave(spinlock_t *lock, unsigned long *flags)
+{
+       int ret;
+
+       *flags = 0;
+       ret = rt_mutex_trylock(&lock->lock);
+       if (ret) {
+               migrate_disable();
+               spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
+       }
+       return ret;
+}
+EXPORT_SYMBOL(rt_spin_trylock_irqsave);
+
+int atomic_dec_and_spin_lock(atomic_t *atomic, spinlock_t *lock)
+{
+       /* Subtract 1 from counter unless that drops it to 0 (ie. it was 1) */
+       if (atomic_add_unless(atomic, -1, 1))
+               return 0;
+       rt_spin_lock(lock);
+       if (atomic_dec_and_test(atomic))
+               return 1;
+       rt_spin_unlock(lock);
+       return 0;
+}
+EXPORT_SYMBOL(atomic_dec_and_spin_lock);
+
+       void
+__rt_spin_lock_init(spinlock_t *lock, char *name, struct lock_class_key *key)
+{
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+       /*
+        * Make sure we are not reinitializing a held lock:
+        */
+       debug_check_no_locks_freed((void *)lock, sizeof(*lock));
+       lockdep_init_map(&lock->dep_map, name, key, 0);
+#endif
+}
+EXPORT_SYMBOL(__rt_spin_lock_init);
+
+#endif /* PREEMPT_RT_FULL */
+
+#ifdef CONFIG_PREEMPT_RT_FULL
+       static inline int __sched
+__mutex_lock_check_stamp(struct rt_mutex *lock, struct ww_acquire_ctx *ctx)
+{
+       struct ww_mutex *ww = container_of(lock, struct ww_mutex, base.lock);
+       struct ww_acquire_ctx *hold_ctx = ACCESS_ONCE(ww->ctx);
+
+       if (!hold_ctx)
+               return 0;
+
+       if (unlikely(ctx == hold_ctx))
+               return -EALREADY;
+
+       if (ctx->stamp - hold_ctx->stamp <= LONG_MAX &&
+           (ctx->stamp != hold_ctx->stamp || ctx > hold_ctx)) {
+#ifdef CONFIG_DEBUG_MUTEXES
+               DEBUG_LOCKS_WARN_ON(ctx->contending_lock);
+               ctx->contending_lock = ww;
+#endif
+               return -EDEADLK;
+       }
+
+       return 0;
+}
+#else
+       static inline int __sched
+__mutex_lock_check_stamp(struct rt_mutex *lock, struct ww_acquire_ctx *ctx)
+{
+       BUG();
+       return 0;
+}
+
+#endif
+
+static inline int
+try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
+                    struct rt_mutex_waiter *waiter)
+{
+       return __try_to_take_rt_mutex(lock, task, waiter, STEAL_NORMAL);
+}
+
+/*
+ * Task blocks on lock.
+ *
+ * Prepare waiter and propagate pi chain
+ *
+ * This must be called with lock->wait_lock held and interrupts disabled
+ */
+static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
+                                  struct rt_mutex_waiter *waiter,
+                                  struct task_struct *task,
+                                  enum rtmutex_chainwalk chwalk)
+{
+       struct task_struct *owner = rt_mutex_owner(lock);
+       struct rt_mutex_waiter *top_waiter = waiter;
+       struct rt_mutex *next_lock;
+       int chain_walk = 0, res;
+
+       lockdep_assert_held(&lock->wait_lock);
+
+       /*
+        * Early deadlock detection. We really don't want the task to
+        * enqueue on itself just to untangle the mess later. It's not
+        * only an optimization. We drop the locks, so another waiter
+        * can come in before the chain walk detects the deadlock. So
+        * the other will detect the deadlock and return -EDEADLOCK,
+        * which is wrong, as the other waiter is not in a deadlock
+        * situation.
+        */
+       if (owner == task)
+               return -EDEADLK;
+
+       raw_spin_lock(&task->pi_lock);
+
+       /*
+        * In the case of futex requeue PI, this will be a proxy
+        * lock. The task will wake unaware that it is enqueueed on
+        * this lock. Avoid blocking on two locks and corrupting
+        * pi_blocked_on via the PI_WAKEUP_INPROGRESS
+        * flag. futex_wait_requeue_pi() sets this when it wakes up
+        * before requeue (due to a signal or timeout). Do not enqueue
+        * the task if PI_WAKEUP_INPROGRESS is set.
+        */
+       if (task != current && task->pi_blocked_on == PI_WAKEUP_INPROGRESS) {
+               raw_spin_unlock(&task->pi_lock);
+               return -EAGAIN;
+       }
+
+       BUG_ON(rt_mutex_real_waiter(task->pi_blocked_on));
+
+       rt_mutex_adjust_prio(task);
+       waiter->task = task;
+       waiter->lock = lock;
+       waiter->prio = task->prio;
+       waiter->deadline = task->dl.deadline;
+
+       /* Get the top priority waiter on the lock */
+       if (rt_mutex_has_waiters(lock))
+               top_waiter = rt_mutex_top_waiter(lock);
+       rt_mutex_enqueue(lock, waiter);
+
+       task->pi_blocked_on = waiter;
+
+       raw_spin_unlock(&task->pi_lock);
+
+       if (!owner)
+               return 0;
+
+       raw_spin_lock(&owner->pi_lock);
+       if (waiter == rt_mutex_top_waiter(lock)) {
+               rt_mutex_dequeue_pi(owner, top_waiter);
+               rt_mutex_enqueue_pi(owner, waiter);
+
+               rt_mutex_adjust_prio(owner);
+               if (rt_mutex_real_waiter(owner->pi_blocked_on))
+                       chain_walk = 1;
+       } else if (rt_mutex_cond_detect_deadlock(waiter, chwalk)) {
+               chain_walk = 1;
+       }
 
        /* Store the lock on which owner is blocked or NULL */
        next_lock = task_blocked_on_lock(owner);
 
        raw_spin_unlock(&owner->pi_lock);
+       /*
+        * Even if full deadlock detection is on, if the owner is not
+        * blocked itself, we can avoid finding this out in the chain
+        * walk.
+        */
+       if (!chain_walk || !next_lock)
+               return 0;
+
+       /*
+        * The owner can't disappear while holding a lock,
+        * so the owner struct is protected by wait_lock.
+        * Gets dropped in rt_mutex_adjust_prio_chain()!
+        */
+       get_task_struct(owner);
+
+       raw_spin_unlock_irq(&lock->wait_lock);
+
+       res = rt_mutex_adjust_prio_chain(owner, chwalk, lock,
+                                        next_lock, waiter, task);
+
+       raw_spin_lock_irq(&lock->wait_lock);
+
+       return res;
+}
+
+/*
+ * Remove the top waiter from the current tasks pi waiter tree and
+ * queue it up.
+ *
+ * Called with lock->wait_lock held and interrupts disabled.
+ */
+static void mark_wakeup_next_waiter(struct wake_q_head *wake_q,
+                                   struct wake_q_head *wake_sleeper_q,
+                                   struct rt_mutex *lock)
+{
+       struct rt_mutex_waiter *waiter;
+
+       raw_spin_lock(&current->pi_lock);
+
+       waiter = rt_mutex_top_waiter(lock);
+
+       /*
+        * Remove it from current->pi_waiters and deboost.
+        *
+        * We must in fact deboost here in order to ensure we call
+        * rt_mutex_setprio() to update p->pi_top_task before the
+        * task unblocks.
+        */
+       rt_mutex_dequeue_pi(current, waiter);
+       rt_mutex_adjust_prio(current);
+
+       /*
+        * As we are waking up the top waiter, and the waiter stays
+        * queued on the lock until it gets the lock, this lock
+        * obviously has waiters. Just set the bit here and this has
+        * the added benefit of forcing all new tasks into the
+        * slow path making sure no task of lower priority than
+        * the top waiter can steal this lock.
+        */
+       lock->owner = (void *) RT_MUTEX_HAS_WAITERS;
+
+       /*
+        * We deboosted before waking the top waiter task such that we don't
+        * run two tasks with the 'same' priority (and ensure the
+        * p->pi_top_task pointer points to a blocked task). This however can
+        * lead to priority inversion if we would get preempted after the
+        * deboost but before waking our donor task, hence the preempt_disable()
+        * before unlock.
+        *
+        * Pairs with preempt_enable() in rt_mutex_postunlock();
+        */
+       preempt_disable();
+       if (waiter->savestate)
+               wake_q_add_sleeper(wake_sleeper_q, waiter->task);
+       else
+               wake_q_add(wake_q, waiter->task);
+       raw_spin_unlock(&current->pi_lock);
+}
+
+/*
+ * Remove a waiter from a lock and give up
+ *
+ * Must be called with lock->wait_lock held and interrupts disabled. I must
+ * have just failed to try_to_take_rt_mutex().
+ */
+static void remove_waiter(struct rt_mutex *lock,
+                         struct rt_mutex_waiter *waiter)
+{
+       bool is_top_waiter = (waiter == rt_mutex_top_waiter(lock));
+       struct task_struct *owner = rt_mutex_owner(lock);
+       struct rt_mutex *next_lock = NULL;
+
+       lockdep_assert_held(&lock->wait_lock);
+
+       raw_spin_lock(&current->pi_lock);
+       rt_mutex_dequeue(lock, waiter);
+       current->pi_blocked_on = NULL;
+       raw_spin_unlock(&current->pi_lock);
+
+       /*
+        * Only update priority if the waiter was the highest priority
+        * waiter of the lock and there is an owner to update.
+        */
+       if (!owner || !is_top_waiter)
+               return;
+
+       raw_spin_lock(&owner->pi_lock);
+
+       rt_mutex_dequeue_pi(owner, waiter);
+
+       if (rt_mutex_has_waiters(lock))
+               rt_mutex_enqueue_pi(owner, rt_mutex_top_waiter(lock));
+
+       rt_mutex_adjust_prio(owner);
+
+       /* Store the lock on which owner is blocked or NULL */
+       if (rt_mutex_real_waiter(owner->pi_blocked_on))
+               next_lock = task_blocked_on_lock(owner);
+
+       raw_spin_unlock(&owner->pi_lock);
 
        /*
         * Don't walk the chain, if the owner task is not blocked
@@ -1163,21 +1586,30 @@ void rt_mutex_adjust_pi(struct task_struct *task)
        raw_spin_lock_irqsave(&task->pi_lock, flags);
 
        waiter = task->pi_blocked_on;
-       if (!waiter || (waiter->prio == task->prio &&
-                       !dl_prio(task->prio))) {
+       if (!rt_mutex_real_waiter(waiter) ||
+           rt_mutex_waiter_equal(waiter, task_to_waiter(task))) {
                raw_spin_unlock_irqrestore(&task->pi_lock, flags);
                return;
        }
        next_lock = waiter->lock;
-       raw_spin_unlock_irqrestore(&task->pi_lock, flags);
 
        /* gets dropped in rt_mutex_adjust_prio_chain()! */
        get_task_struct(task);
 
+       raw_spin_unlock_irqrestore(&task->pi_lock, flags);
        rt_mutex_adjust_prio_chain(task, RT_MUTEX_MIN_CHAINWALK, NULL,
                                   next_lock, NULL, task);
 }
 
+void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter, bool savestate)
+{
+       debug_rt_mutex_init_waiter(waiter);
+       RB_CLEAR_NODE(&waiter->pi_tree_entry);
+       RB_CLEAR_NODE(&waiter->tree_entry);
+       waiter->task = NULL;
+       waiter->savestate = savestate;
+}
+
 /**
  * __rt_mutex_slowlock() - Perform the wait-wake-try-to-take loop
  * @lock:               the rt_mutex to take
@@ -1191,7 +1623,8 @@ void rt_mutex_adjust_pi(struct task_struct *task)
 static int __sched
 __rt_mutex_slowlock(struct rt_mutex *lock, int state,
                    struct hrtimer_sleeper *timeout,
-                   struct rt_mutex_waiter *waiter)
+                   struct rt_mutex_waiter *waiter,
+                   struct ww_acquire_ctx *ww_ctx)
 {
        int ret = 0;
 
@@ -1200,16 +1633,17 @@ __rt_mutex_slowlock(struct rt_mutex *lock, int state,
                if (try_to_take_rt_mutex(lock, current, waiter))
                        break;
 
-               /*
-                * TASK_INTERRUPTIBLE checks for signals and
-                * timeout. Ignored otherwise.
-                */
-               if (unlikely(state == TASK_INTERRUPTIBLE)) {
-                       /* Signal pending? */
-                       if (signal_pending(current))
-                               ret = -EINTR;
-                       if (timeout && !timeout->task)
-                               ret = -ETIMEDOUT;
+               if (timeout && !timeout->task) {
+                       ret = -ETIMEDOUT;
+                       break;
+               }
+               if (signal_pending_state(state, current)) {
+                       ret = -EINTR;
+                       break;
+               }
+
+               if (ww_ctx && ww_ctx->acquired > 0) {
+                       ret = __mutex_lock_check_stamp(lock, ww_ctx);
                        if (ret)
                                break;
                }
@@ -1218,34 +1652,162 @@ __rt_mutex_slowlock(struct rt_mutex *lock, int state,
 
                debug_rt_mutex_print_deadlock(waiter);
 
-               schedule();
+               schedule();
+
+               raw_spin_lock_irq(&lock->wait_lock);
+               set_current_state(state);
+       }
+
+       __set_current_state(TASK_RUNNING);
+       return ret;
+}
+
+static void rt_mutex_handle_deadlock(int res, int detect_deadlock,
+                                    struct rt_mutex_waiter *w)
+{
+       /*
+        * If the result is not -EDEADLOCK or the caller requested
+        * deadlock detection, nothing to do here.
+        */
+       if (res != -EDEADLOCK || detect_deadlock)
+               return;
+
+       /*
+        * Yell lowdly and stop the task right here.
+        */
+       rt_mutex_print_deadlock(w);
+       while (1) {
+               set_current_state(TASK_INTERRUPTIBLE);
+               schedule();
+       }
+}
+
+static __always_inline void ww_mutex_lock_acquired(struct ww_mutex *ww,
+                                                  struct ww_acquire_ctx *ww_ctx)
+{
+#ifdef CONFIG_DEBUG_MUTEXES
+       /*
+        * If this WARN_ON triggers, you used ww_mutex_lock to acquire,
+        * but released with a normal mutex_unlock in this call.
+        *
+        * This should never happen, always use ww_mutex_unlock.
+        */
+       DEBUG_LOCKS_WARN_ON(ww->ctx);
+
+       /*
+        * Not quite done after calling ww_acquire_done() ?
+        */
+       DEBUG_LOCKS_WARN_ON(ww_ctx->done_acquire);
+
+       if (ww_ctx->contending_lock) {
+               /*
+                * After -EDEADLK you tried to
+                * acquire a different ww_mutex? Bad!
+                */
+               DEBUG_LOCKS_WARN_ON(ww_ctx->contending_lock != ww);
+
+               /*
+                * You called ww_mutex_lock after receiving -EDEADLK,
+                * but 'forgot' to unlock everything else first?
+                */
+               DEBUG_LOCKS_WARN_ON(ww_ctx->acquired > 0);
+               ww_ctx->contending_lock = NULL;
+       }
+
+       /*
+        * Naughty, using a different class will lead to undefined behavior!
+        */
+       DEBUG_LOCKS_WARN_ON(ww_ctx->ww_class != ww->ww_class);
+#endif
+       ww_ctx->acquired++;
+}
+
+#ifdef CONFIG_PREEMPT_RT_FULL
+static void ww_mutex_account_lock(struct rt_mutex *lock,
+                                 struct ww_acquire_ctx *ww_ctx)
+{
+       struct ww_mutex *ww = container_of(lock, struct ww_mutex, base.lock);
+       struct rt_mutex_waiter *waiter, *n;
+
+       /*
+        * This branch gets optimized out for the common case,
+        * and is only important for ww_mutex_lock.
+        */
+       ww_mutex_lock_acquired(ww, ww_ctx);
+       ww->ctx = ww_ctx;
+
+       /*
+        * Give any possible sleeping processes the chance to wake up,
+        * so they can recheck if they have to back off.
+        */
+       rbtree_postorder_for_each_entry_safe(waiter, n, &lock->waiters,
+                                            tree_entry) {
+               /* XXX debug rt mutex waiter wakeup */
+
+               BUG_ON(waiter->lock != lock);
+               rt_mutex_wake_waiter(waiter);
+       }
+}
+
+#else
+
+static void ww_mutex_account_lock(struct rt_mutex *lock,
+                                 struct ww_acquire_ctx *ww_ctx)
+{
+       BUG();
+}
+#endif
+
+int __sched rt_mutex_slowlock_locked(struct rt_mutex *lock, int state,
+                                    struct hrtimer_sleeper *timeout,
+                                    enum rtmutex_chainwalk chwalk,
+                                    struct ww_acquire_ctx *ww_ctx,
+                                    struct rt_mutex_waiter *waiter)
+{
+       int ret;
+
+       /* Try to acquire the lock again: */
+       if (try_to_take_rt_mutex(lock, current, NULL)) {
+               if (ww_ctx)
+                       ww_mutex_account_lock(lock, ww_ctx);
+               return 0;
+       }
+
+       set_current_state(state);
+
+       /* Setup the timer, when timeout != NULL */
+       if (unlikely(timeout))
+               hrtimer_start_expires(&timeout->timer, HRTIMER_MODE_ABS);
+
+       ret = task_blocks_on_rt_mutex(lock, waiter, current, chwalk);
 
-               raw_spin_lock_irq(&lock->wait_lock);
-               set_current_state(state);
+       if (likely(!ret)) {
+               /* sleep on the mutex */
+               ret = __rt_mutex_slowlock(lock, state, timeout, waiter,
+                                         ww_ctx);
+       } else if (ww_ctx) {
+               /* ww_mutex received EDEADLK, let it become EALREADY */
+               ret = __mutex_lock_check_stamp(lock, ww_ctx);
+               BUG_ON(!ret);
        }
 
-       __set_current_state(TASK_RUNNING);
-       return ret;
-}
-
-static void rt_mutex_handle_deadlock(int res, int detect_deadlock,
-                                    struct rt_mutex_waiter *w)
-{
-       /*
-        * If the result is not -EDEADLOCK or the caller requested
-        * deadlock detection, nothing to do here.
-        */
-       if (res != -EDEADLOCK || detect_deadlock)
-               return;
+       if (unlikely(ret)) {
+               __set_current_state(TASK_RUNNING);
+               if (rt_mutex_has_waiters(lock))
+                       remove_waiter(lock, waiter);
+               /* ww_mutex want to report EDEADLK/EALREADY, let them */
+               if (!ww_ctx)
+                       rt_mutex_handle_deadlock(ret, chwalk, waiter);
+       } else if (ww_ctx) {
+               ww_mutex_account_lock(lock, ww_ctx);
+       }
 
        /*
-        * Yell lowdly and stop the task right here.
+        * try_to_take_rt_mutex() sets the waiter bit
+        * unconditionally. We might have to fix that up.
         */
-       rt_mutex_print_deadlock(w);
-       while (1) {
-               set_current_state(TASK_INTERRUPTIBLE);
-               schedule();
-       }
+       fixup_rt_mutex_waiters(lock);
+       return ret;
 }
 
 /*
@@ -1254,15 +1816,14 @@ static void rt_mutex_handle_deadlock(int res, int detect_deadlock,
 static int __sched
 rt_mutex_slowlock(struct rt_mutex *lock, int state,
                  struct hrtimer_sleeper *timeout,
-                 enum rtmutex_chainwalk chwalk)
+                 enum rtmutex_chainwalk chwalk,
+                 struct ww_acquire_ctx *ww_ctx)
 {
        struct rt_mutex_waiter waiter;
        unsigned long flags;
        int ret = 0;
 
-       debug_rt_mutex_init_waiter(&waiter);
-       RB_CLEAR_NODE(&waiter.pi_tree_entry);
-       RB_CLEAR_NODE(&waiter.tree_entry);
+       rt_mutex_init_waiter(&waiter, false);
 
        /*
         * Technically we could use raw_spin_[un]lock_irq() here, but this can
@@ -1274,45 +1835,30 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state,
         */
        raw_spin_lock_irqsave(&lock->wait_lock, flags);
 
-       /* Try to acquire the lock again: */
-       if (try_to_take_rt_mutex(lock, current, NULL)) {
-               raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
-               return 0;
-       }
+       ret = rt_mutex_slowlock_locked(lock, state, timeout, chwalk, ww_ctx,
+                                      &waiter);
 
-       set_current_state(state);
+       raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
 
-       /* Setup the timer, when timeout != NULL */
+       /* Remove pending timer: */
        if (unlikely(timeout))
-               hrtimer_start_expires(&timeout->timer, HRTIMER_MODE_ABS);
+               hrtimer_cancel(&timeout->timer);
 
-       ret = task_blocks_on_rt_mutex(lock, &waiter, current, chwalk);
+       debug_rt_mutex_free_waiter(&waiter);
 
-       if (likely(!ret))
-               /* sleep on the mutex */
-               ret = __rt_mutex_slowlock(lock, state, timeout, &waiter);
+       return ret;
+}
 
-       if (unlikely(ret)) {
-               __set_current_state(TASK_RUNNING);
-               if (rt_mutex_has_waiters(lock))
-                       remove_waiter(lock, &waiter);
-               rt_mutex_handle_deadlock(ret, chwalk, &waiter);
-       }
+static inline int __rt_mutex_slowtrylock(struct rt_mutex *lock)
+{
+       int ret = try_to_take_rt_mutex(lock, current, NULL);
 
        /*
-        * try_to_take_rt_mutex() sets the waiter bit
-        * unconditionally. We might have to fix that up.
+        * try_to_take_rt_mutex() sets the lock waiters bit
+        * unconditionally. Clean this up.
         */
        fixup_rt_mutex_waiters(lock);
 
-       raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
-
-       /* Remove pending timer: */
-       if (unlikely(timeout))
-               hrtimer_cancel(&timeout->timer);
-
-       debug_rt_mutex_free_waiter(&waiter);
-
        return ret;
 }
 
@@ -1338,13 +1884,7 @@ static inline int rt_mutex_slowtrylock(struct rt_mutex *lock)
         */
        raw_spin_lock_irqsave(&lock->wait_lock, flags);
 
-       ret = try_to_take_rt_mutex(lock, current, NULL);
-
-       /*
-        * try_to_take_rt_mutex() sets the lock waiters bit
-        * unconditionally. Clean this up.
-        */
-       fixup_rt_mutex_waiters(lock);
+       ret = __rt_mutex_slowtrylock(lock);
 
        raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
 
@@ -1353,10 +1893,12 @@ static inline int rt_mutex_slowtrylock(struct rt_mutex *lock)
 
 /*
  * Slow path to release a rt-mutex.
- * Return whether the current task needs to undo a potential priority boosting.
+ *
+ * Return whether the current task needs to call rt_mutex_postunlock().
  */
 static bool __sched rt_mutex_slowunlock(struct rt_mutex *lock,
-                                       struct wake_q_head *wake_q)
+                                       struct wake_q_head *wake_q,
+                                       struct wake_q_head *wake_sleeper_q)
 {
        unsigned long flags;
 
@@ -1365,8 +1907,6 @@ static bool __sched rt_mutex_slowunlock(struct rt_mutex *lock,
 
        debug_rt_mutex_unlock(lock);
 
-       rt_mutex_deadlock_account_unlock(current);
-
        /*
         * We must be careful here if the fast path is enabled. If we
         * have no waiters queued we cannot set owner to NULL here
@@ -1412,12 +1952,10 @@ static bool __sched rt_mutex_slowunlock(struct rt_mutex *lock,
         *
         * Queue the next waiter for wakeup once we release the wait_lock.
         */
-       mark_wakeup_next_waiter(wake_q, lock);
-
+       mark_wakeup_next_waiter(wake_q, wake_sleeper_q, lock);
        raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
 
-       /* check PI boosting */
-       return true;
+       return true; /* call rt_mutex_postunlock() */
 }
 
 /*
@@ -1428,63 +1966,97 @@ static bool __sched rt_mutex_slowunlock(struct rt_mutex *lock,
  */
 static inline int
 rt_mutex_fastlock(struct rt_mutex *lock, int state,
+                 struct ww_acquire_ctx *ww_ctx,
                  int (*slowfn)(struct rt_mutex *lock, int state,
                                struct hrtimer_sleeper *timeout,
-                               enum rtmutex_chainwalk chwalk))
+                               enum rtmutex_chainwalk chwalk,
+                               struct ww_acquire_ctx *ww_ctx))
 {
-       if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current))) {
-               rt_mutex_deadlock_account_lock(lock, current);
+       if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current)))
                return 0;
-       } else
-               return slowfn(lock, state, NULL, RT_MUTEX_MIN_CHAINWALK);
+
+       /*
+        * If rt_mutex blocks, the function sched_submit_work will not call
+        * blk_schedule_flush_plug (because tsk_is_pi_blocked would be true).
+        * We must call blk_schedule_flush_plug here, if we don't call it,
+        * a deadlock in device mapper may happen.
+        */
+       if (unlikely(blk_needs_flush_plug(current)))
+               blk_schedule_flush_plug(current);
+
+       return slowfn(lock, state, NULL, RT_MUTEX_MIN_CHAINWALK, ww_ctx);
 }
 
 static inline int
 rt_mutex_timed_fastlock(struct rt_mutex *lock, int state,
                        struct hrtimer_sleeper *timeout,
                        enum rtmutex_chainwalk chwalk,
+                       struct ww_acquire_ctx *ww_ctx,
                        int (*slowfn)(struct rt_mutex *lock, int state,
                                      struct hrtimer_sleeper *timeout,
-                                     enum rtmutex_chainwalk chwalk))
+                                     enum rtmutex_chainwalk chwalk,
+                                     struct ww_acquire_ctx *ww_ctx))
 {
        if (chwalk == RT_MUTEX_MIN_CHAINWALK &&
-           likely(rt_mutex_cmpxchg_acquire(lock, NULL, current))) {
-               rt_mutex_deadlock_account_lock(lock, current);
+           likely(rt_mutex_cmpxchg_acquire(lock, NULL, current)))
                return 0;
-       } else
-               return slowfn(lock, state, timeout, chwalk);
+
+       if (unlikely(blk_needs_flush_plug(current)))
+               blk_schedule_flush_plug(current);
+
+       return slowfn(lock, state, timeout, chwalk, ww_ctx);
 }
 
 static inline int
 rt_mutex_fasttrylock(struct rt_mutex *lock,
                     int (*slowfn)(struct rt_mutex *lock))
 {
-       if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current))) {
-               rt_mutex_deadlock_account_lock(lock, current);
+       if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current)))
                return 1;
-       }
+
        return slowfn(lock);
 }
 
+/*
+ * Performs the wakeup of the the top-waiter and re-enables preemption.
+ */
+void rt_mutex_postunlock(struct wake_q_head *wake_q,
+                        struct wake_q_head *wq_sleeper)
+{
+       wake_up_q(wake_q);
+       wake_up_q_sleeper(wq_sleeper);
+
+       /* Pairs with preempt_disable() in rt_mutex_slowunlock() */
+       preempt_enable();
+}
+
 static inline void
 rt_mutex_fastunlock(struct rt_mutex *lock,
                    bool (*slowfn)(struct rt_mutex *lock,
-                                  struct wake_q_head *wqh))
+                                  struct wake_q_head *wqh,
+                                  struct wake_q_head *wq_sleeper))
 {
        WAKE_Q(wake_q);
+       WAKE_Q(wake_sleeper_q);
 
-       if (likely(rt_mutex_cmpxchg_release(lock, current, NULL))) {
-               rt_mutex_deadlock_account_unlock(current);
+       if (likely(rt_mutex_cmpxchg_release(lock, current, NULL)))
+               return;
 
-       } else {
-               bool deboost = slowfn(lock, &wake_q);
+       if (slowfn(lock, &wake_q,  &wake_sleeper_q))
+               rt_mutex_postunlock(&wake_q, &wake_sleeper_q);
+}
 
-               wake_up_q(&wake_q);
+/**
+ * rt_mutex_lock_state - lock a rt_mutex with a given state
+ *
+ * @lock:      The rt_mutex to be locked
+ * @state:     The state to set when blocking on the rt_mutex
+ */
+int __sched rt_mutex_lock_state(struct rt_mutex *lock, int state)
+{
+       might_sleep();
 
-               /* Undo pi boosting if necessary: */
-               if (deboost)
-                       rt_mutex_adjust_prio(current);
-       }
+       return rt_mutex_fastlock(lock, state, NULL, rt_mutex_slowlock);
 }
 
 /**
@@ -1494,15 +2066,13 @@ rt_mutex_fastunlock(struct rt_mutex *lock,
  */
 void __sched rt_mutex_lock(struct rt_mutex *lock)
 {
-       might_sleep();
-
-       rt_mutex_fastlock(lock, TASK_UNINTERRUPTIBLE, rt_mutex_slowlock);
+       rt_mutex_lock_state(lock, TASK_UNINTERRUPTIBLE);
 }
 EXPORT_SYMBOL_GPL(rt_mutex_lock);
 
 /**
  * rt_mutex_lock_interruptible - lock a rt_mutex interruptible
- *
+ **
  * @lock:              the rt_mutex to be locked
  *
  * Returns:
@@ -1511,23 +2081,37 @@ EXPORT_SYMBOL_GPL(rt_mutex_lock);
  */
 int __sched rt_mutex_lock_interruptible(struct rt_mutex *lock)
 {
-       might_sleep();
-
-       return rt_mutex_fastlock(lock, TASK_INTERRUPTIBLE, rt_mutex_slowlock);
+       return rt_mutex_lock_state(lock, TASK_INTERRUPTIBLE);
 }
 EXPORT_SYMBOL_GPL(rt_mutex_lock_interruptible);
 
+/**
+ * rt_mutex_lock_killable - lock a rt_mutex killable
+ *
+ * @lock:              the rt_mutex to be locked
+ * @detect_deadlock:   deadlock detection on/off
+ *
+ * Returns:
+ *  0          on success
+ * -EINTR      when interrupted by a signal
+ */
+int __sched rt_mutex_lock_killable(struct rt_mutex *lock)
+{
+       return rt_mutex_lock_state(lock, TASK_KILLABLE);
+}
+EXPORT_SYMBOL_GPL(rt_mutex_lock_killable);
+
 /*
- * Futex variant with full deadlock detection.
+ * Futex variant, must not use fastpath.
  */
-int rt_mutex_timed_futex_lock(struct rt_mutex *lock,
-                             struct hrtimer_sleeper *timeout)
+int __sched rt_mutex_futex_trylock(struct rt_mutex *lock)
 {
-       might_sleep();
+       return rt_mutex_slowtrylock(lock);
+}
 
-       return rt_mutex_timed_fastlock(lock, TASK_INTERRUPTIBLE, timeout,
-                                      RT_MUTEX_FULL_CHAINWALK,
-                                      rt_mutex_slowlock);
+int __sched __rt_mutex_futex_trylock(struct rt_mutex *lock)
+{
+       return __rt_mutex_slowtrylock(lock);
 }
 
 /**
@@ -1550,6 +2134,7 @@ rt_mutex_timed_lock(struct rt_mutex *lock, struct hrtimer_sleeper *timeout)
 
        return rt_mutex_timed_fastlock(lock, TASK_INTERRUPTIBLE, timeout,
                                       RT_MUTEX_MIN_CHAINWALK,
+                                      NULL,
                                       rt_mutex_slowlock);
 }
 EXPORT_SYMBOL_GPL(rt_mutex_timed_lock);
@@ -1567,7 +2152,11 @@ EXPORT_SYMBOL_GPL(rt_mutex_timed_lock);
  */
 int __sched rt_mutex_trylock(struct rt_mutex *lock)
 {
+#ifdef CONFIG_PREEMPT_RT_FULL
+       if (WARN_ON_ONCE(in_irq() || in_nmi()))
+#else
        if (WARN_ON_ONCE(in_irq() || in_nmi() || in_serving_softirq()))
+#endif
                return 0;
 
        return rt_mutex_fasttrylock(lock, rt_mutex_slowtrylock);
@@ -1585,21 +2174,54 @@ void __sched rt_mutex_unlock(struct rt_mutex *lock)
 }
 EXPORT_SYMBOL_GPL(rt_mutex_unlock);
 
+static bool __sched __rt_mutex_unlock_common(struct rt_mutex *lock,
+                                            struct wake_q_head *wake_q,
+                                            struct wake_q_head *wq_sleeper)
+{
+       lockdep_assert_held(&lock->wait_lock);
+
+       debug_rt_mutex_unlock(lock);
+
+       if (!rt_mutex_has_waiters(lock)) {
+               lock->owner = NULL;
+               return false; /* done */
+       }
+
+       /*
+        * We've already deboosted, mark_wakeup_next_waiter() will
+        * retain preempt_disabled when we drop the wait_lock, to
+        * avoid inversion prior to the wakeup.  preempt_disable()
+        * therein pairs with rt_mutex_postunlock().
+        */
+       mark_wakeup_next_waiter(wake_q, wq_sleeper, lock);
+
+       return true; /* call postunlock() */
+}
+
 /**
- * rt_mutex_futex_unlock - Futex variant of rt_mutex_unlock
- * @lock: the rt_mutex to be unlocked
- *
- * Returns: true/false indicating whether priority adjustment is
- * required or not.
+ * Futex variant, that since futex variants do not use the fast-path, can be
+ * simple and will not need to retry.
  */
-bool __sched rt_mutex_futex_unlock(struct rt_mutex *lock,
-                                  struct wake_q_head *wqh)
+bool __sched __rt_mutex_futex_unlock(struct rt_mutex *lock,
+                                   struct wake_q_head *wake_q,
+                                   struct wake_q_head *wq_sleeper)
 {
-       if (likely(rt_mutex_cmpxchg_release(lock, current, NULL))) {
-               rt_mutex_deadlock_account_unlock(current);
-               return false;
-       }
-       return rt_mutex_slowunlock(lock, wqh);
+       return __rt_mutex_unlock_common(lock, wake_q, wq_sleeper);
+}
+
+void __sched rt_mutex_futex_unlock(struct rt_mutex *lock)
+{
+       WAKE_Q(wake_q);
+       WAKE_Q(wake_sleeper_q);
+       unsigned long flags;
+       bool postunlock;
+
+       raw_spin_lock_irqsave(&lock->wait_lock, flags);
+       postunlock = __rt_mutex_futex_unlock(lock, &wake_q, &wake_sleeper_q);
+       raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
+
+       if (postunlock)
+               rt_mutex_postunlock(&wake_q, &wake_sleeper_q);
 }
 
 /**
@@ -1632,13 +2254,12 @@ EXPORT_SYMBOL_GPL(rt_mutex_destroy);
 void __rt_mutex_init(struct rt_mutex *lock, const char *name)
 {
        lock->owner = NULL;
-       raw_spin_lock_init(&lock->wait_lock);
        lock->waiters = RB_ROOT;
        lock->waiters_leftmost = NULL;
 
        debug_rt_mutex_init(lock, name);
 }
-EXPORT_SYMBOL_GPL(__rt_mutex_init);
+EXPORT_SYMBOL(__rt_mutex_init);
 
 /**
  * rt_mutex_init_proxy_locked - initialize and lock a rt_mutex on behalf of a
@@ -1653,10 +2274,9 @@ EXPORT_SYMBOL_GPL(__rt_mutex_init);
 void rt_mutex_init_proxy_locked(struct rt_mutex *lock,
                                struct task_struct *proxy_owner)
 {
-       __rt_mutex_init(lock, NULL);
+       rt_mutex_init(lock);
        debug_rt_mutex_proxy_lock(lock, proxy_owner);
        rt_mutex_set_owner(lock, proxy_owner);
-       rt_mutex_deadlock_account_lock(lock, proxy_owner);
 }
 
 /**
@@ -1672,34 +2292,44 @@ void rt_mutex_proxy_unlock(struct rt_mutex *lock,
 {
        debug_rt_mutex_proxy_unlock(lock);
        rt_mutex_set_owner(lock, NULL);
-       rt_mutex_deadlock_account_unlock(proxy_owner);
 }
 
-/**
- * rt_mutex_start_proxy_lock() - Start lock acquisition for another task
- * @lock:              the rt_mutex to take
- * @waiter:            the pre-initialized rt_mutex_waiter
- * @task:              the task to prepare
- *
- * Returns:
- *  0 - task blocked on lock
- *  1 - acquired the lock for task, caller should wake it up
- * <0 - error
- *
- * Special API call for FUTEX_REQUEUE_PI support.
- */
-int rt_mutex_start_proxy_lock(struct rt_mutex *lock,
+int __rt_mutex_start_proxy_lock(struct rt_mutex *lock,
                              struct rt_mutex_waiter *waiter,
                              struct task_struct *task)
 {
        int ret;
 
-       raw_spin_lock_irq(&lock->wait_lock);
-
-       if (try_to_take_rt_mutex(lock, task, NULL)) {
-               raw_spin_unlock_irq(&lock->wait_lock);
+       if (try_to_take_rt_mutex(lock, task, NULL))
                return 1;
+
+#ifdef CONFIG_PREEMPT_RT_FULL
+       /*
+        * In PREEMPT_RT there's an added race.
+        * If the task, that we are about to requeue, times out,
+        * it can set the PI_WAKEUP_INPROGRESS. This tells the requeue
+        * to skip this task. But right after the task sets
+        * its pi_blocked_on to PI_WAKEUP_INPROGRESS it can then
+        * block on the spin_lock(&hb->lock), which in RT is an rtmutex.
+        * This will replace the PI_WAKEUP_INPROGRESS with the actual
+        * lock that it blocks on. We *must not* place this task
+        * on this proxy lock in that case.
+        *
+        * To prevent this race, we first take the task's pi_lock
+        * and check if it has updated its pi_blocked_on. If it has,
+        * we assume that it woke up and we return -EAGAIN.
+        * Otherwise, we set the task's pi_blocked_on to
+        * PI_REQUEUE_INPROGRESS, so that if the task is waking up
+        * it will know that we are in the process of requeuing it.
+        */
+       raw_spin_lock(&task->pi_lock);
+       if (task->pi_blocked_on) {
+               raw_spin_unlock(&task->pi_lock);
+               return -EAGAIN;
        }
+       task->pi_blocked_on = PI_REQUEUE_INPROGRESS;
+       raw_spin_unlock(&task->pi_lock);
+#endif
 
        /* We enforce deadlock detection for futexes */
        ret = task_blocks_on_rt_mutex(lock, waiter, task,
@@ -1715,17 +2345,41 @@ int rt_mutex_start_proxy_lock(struct rt_mutex *lock,
                ret = 0;
        }
 
-       if (unlikely(ret))
+       if (ret && rt_mutex_has_waiters(lock))
                remove_waiter(lock, waiter);
 
-       raw_spin_unlock_irq(&lock->wait_lock);
-
        debug_rt_mutex_print_deadlock(waiter);
 
        return ret;
 }
 
 /**
+ * rt_mutex_start_proxy_lock() - Start lock acquisition for another task
+ * @lock:              the rt_mutex to take
+ * @waiter:            the pre-initialized rt_mutex_waiter
+ * @task:              the task to prepare
+ *
+ * Returns:
+ *  0 - task blocked on lock
+ *  1 - acquired the lock for task, caller should wake it up
+ * <0 - error
+ *
+ * Special API call for FUTEX_REQUEUE_PI support.
+ */
+int rt_mutex_start_proxy_lock(struct rt_mutex *lock,
+                             struct rt_mutex_waiter *waiter,
+                             struct task_struct *task)
+{
+       int ret;
+
+       raw_spin_lock_irq(&lock->wait_lock);
+       ret = __rt_mutex_start_proxy_lock(lock, waiter, task);
+       raw_spin_unlock_irq(&lock->wait_lock);
+
+       return ret;
+}
+
+/**
  * rt_mutex_next_owner - return the next owner of the lock
  *
  * @lock: the rt lock query
@@ -1766,21 +2420,36 @@ int rt_mutex_wait_proxy_lock(struct rt_mutex *lock,
                               struct hrtimer_sleeper *to,
                               struct rt_mutex_waiter *waiter)
 {
+       struct task_struct *tsk = current;
        int ret;
 
        raw_spin_lock_irq(&lock->wait_lock);
-
-       set_current_state(TASK_INTERRUPTIBLE);
-
        /* sleep on the mutex */
-       ret = __rt_mutex_slowlock(lock, TASK_INTERRUPTIBLE, to, waiter);
-
+       set_current_state(TASK_INTERRUPTIBLE);
+       ret = __rt_mutex_slowlock(lock, TASK_INTERRUPTIBLE, to, waiter, NULL);
        /*
         * try_to_take_rt_mutex() sets the waiter bit unconditionally. We might
         * have to fix that up.
         */
        fixup_rt_mutex_waiters(lock);
 
+       /*
+        * RT has a problem here when the wait got interrupted by a timeout
+        * or a signal. task->pi_blocked_on is still set. The task must
+        * acquire the hash bucket lock when returning from this function.
+        *
+        * If the hash bucket lock is contended then the
+        * BUG_ON(rt_mutex_real_waiter(task->pi_blocked_on)) in
+        * task_blocks_on_rt_mutex() will trigger. This can be avoided by
+        * clearing task->pi_blocked_on which removes the task from the
+        * boosting chain of the rtmutex. That's correct because the task
+        * is not longer blocked on it.
+        */
+       if (ret) {
+               raw_spin_lock(&tsk->pi_lock);
+               tsk->pi_blocked_on = NULL;
+               raw_spin_unlock(&tsk->pi_lock);
+       }
        raw_spin_unlock_irq(&lock->wait_lock);
 
        return ret;
@@ -1812,15 +2481,119 @@ bool rt_mutex_cleanup_proxy_lock(struct rt_mutex *lock,
 
        raw_spin_lock_irq(&lock->wait_lock);
        /*
+        * Do an unconditional try-lock, this deals with the lock stealing
+        * state where __rt_mutex_futex_unlock() -> mark_wakeup_next_waiter()
+        * sets a NULL owner.
+        *
+        * We're not interested in the return value, because the subsequent
+        * test on rt_mutex_owner() will infer that. If the trylock succeeded,
+        * we will own the lock and it will have removed the waiter. If we
+        * failed the trylock, we're still not owner and we need to remove
+        * ourselves.
+        */
+       try_to_take_rt_mutex(lock, current, waiter);
+       /*
         * Unless we're the owner; we're still enqueued on the wait_list.
         * So check if we became owner, if not, take us off the wait_list.
         */
        if (rt_mutex_owner(lock) != current) {
                remove_waiter(lock, waiter);
-               fixup_rt_mutex_waiters(lock);
                cleanup = true;
        }
+
+       /*
+        * try_to_take_rt_mutex() sets the waiter bit unconditionally. We might
+        * have to fix that up.
+        */
+       fixup_rt_mutex_waiters(lock);
+
        raw_spin_unlock_irq(&lock->wait_lock);
 
        return cleanup;
 }
+
+static inline int
+ww_mutex_deadlock_injection(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
+{
+#ifdef CONFIG_DEBUG_WW_MUTEX_SLOWPATH
+       unsigned tmp;
+
+       if (ctx->deadlock_inject_countdown-- == 0) {
+               tmp = ctx->deadlock_inject_interval;
+               if (tmp > UINT_MAX/4)
+                       tmp = UINT_MAX;
+               else
+                       tmp = tmp*2 + tmp + tmp/2;
+
+               ctx->deadlock_inject_interval = tmp;
+               ctx->deadlock_inject_countdown = tmp;
+               ctx->contending_lock = lock;
+
+               ww_mutex_unlock(lock);
+
+               return -EDEADLK;
+       }
+#endif
+
+       return 0;
+}
+
+#ifdef CONFIG_PREEMPT_RT_FULL
+int __sched
+__ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ww_ctx)
+{
+       int ret;
+
+       might_sleep();
+
+       mutex_acquire_nest(&lock->base.dep_map, 0, 0, &ww_ctx->dep_map, _RET_IP_);
+       ret = rt_mutex_slowlock(&lock->base.lock, TASK_INTERRUPTIBLE, NULL, 0, ww_ctx);
+       if (ret)
+               mutex_release(&lock->base.dep_map, 1, _RET_IP_);
+       else if (!ret && ww_ctx->acquired > 1)
+               return ww_mutex_deadlock_injection(lock, ww_ctx);
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(__ww_mutex_lock_interruptible);
+
+int __sched
+__ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ww_ctx)
+{
+       int ret;
+
+       might_sleep();
+
+       mutex_acquire_nest(&lock->base.dep_map, 0, 0, &ww_ctx->dep_map, _RET_IP_);
+       ret = rt_mutex_slowlock(&lock->base.lock, TASK_UNINTERRUPTIBLE, NULL, 0, ww_ctx);
+       if (ret)
+               mutex_release(&lock->base.dep_map, 1, _RET_IP_);
+       else if (!ret && ww_ctx->acquired > 1)
+               return ww_mutex_deadlock_injection(lock, ww_ctx);
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(__ww_mutex_lock);
+
+void __sched ww_mutex_unlock(struct ww_mutex *lock)
+{
+       int nest = !!lock->ctx;
+
+       /*
+        * The unlocking fastpath is the 0->1 transition from 'locked'
+        * into 'unlocked' state:
+        */
+       if (nest) {
+#ifdef CONFIG_DEBUG_MUTEXES
+               DEBUG_LOCKS_WARN_ON(!lock->ctx->acquired);
+#endif
+               if (lock->ctx->acquired > 0)
+                       lock->ctx->acquired--;
+               lock->ctx = NULL;
+       }
+
+       mutex_release(&lock->base.dep_map, nest, _RET_IP_);
+       rt_mutex_unlock(&lock->base.lock);
+}
+EXPORT_SYMBOL(ww_mutex_unlock);
+#endif
index c406058..6607802 100644 (file)
@@ -11,8 +11,6 @@
  */
 
 #define rt_mutex_deadlock_check(l)                     (0)
-#define rt_mutex_deadlock_account_lock(m, t)           do { } while (0)
-#define rt_mutex_deadlock_account_unlock(l)            do { } while (0)
 #define debug_rt_mutex_init_waiter(w)                  do { } while (0)
 #define debug_rt_mutex_free_waiter(w)                  do { } while (0)
 #define debug_rt_mutex_lock(l)                         do { } while (0)
index 14cbafe..50c0a10 100644 (file)
@@ -27,6 +27,7 @@ struct rt_mutex_waiter {
        struct rb_node          pi_tree_entry;
        struct task_struct      *task;
        struct rt_mutex         *lock;
+       bool                    savestate;
 #ifdef CONFIG_DEBUG_RT_MUTEXES
        unsigned long           ip;
        struct pid              *deadlock_task_pid;
@@ -99,11 +100,18 @@ enum rtmutex_chainwalk {
 /*
  * PI-futex support (proxy locking functions, etc.):
  */
+#define PI_WAKEUP_INPROGRESS   ((struct rt_mutex_waiter *) 1)
+#define PI_REQUEUE_INPROGRESS  ((struct rt_mutex_waiter *) 2)
+
 extern struct task_struct *rt_mutex_next_owner(struct rt_mutex *lock);
 extern void rt_mutex_init_proxy_locked(struct rt_mutex *lock,
                                       struct task_struct *proxy_owner);
 extern void rt_mutex_proxy_unlock(struct rt_mutex *lock,
                                  struct task_struct *proxy_owner);
+extern void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter, bool savetate);
+extern int __rt_mutex_start_proxy_lock(struct rt_mutex *lock,
+                                    struct rt_mutex_waiter *waiter,
+                                    struct task_struct *task);
 extern int rt_mutex_start_proxy_lock(struct rt_mutex *lock,
                                     struct rt_mutex_waiter *waiter,
                                     struct task_struct *task);
@@ -112,10 +120,26 @@ extern int rt_mutex_wait_proxy_lock(struct rt_mutex *lock,
                               struct rt_mutex_waiter *waiter);
 extern bool rt_mutex_cleanup_proxy_lock(struct rt_mutex *lock,
                                 struct rt_mutex_waiter *waiter);
-extern int rt_mutex_timed_futex_lock(struct rt_mutex *l, struct hrtimer_sleeper *to);
-extern bool rt_mutex_futex_unlock(struct rt_mutex *lock,
-                                 struct wake_q_head *wqh);
-extern void rt_mutex_adjust_prio(struct task_struct *task);
+
+extern int rt_mutex_futex_trylock(struct rt_mutex *l);
+extern int __rt_mutex_futex_trylock(struct rt_mutex *l);
+
+extern void rt_mutex_futex_unlock(struct rt_mutex *lock);
+extern bool __rt_mutex_futex_unlock(struct rt_mutex *lock,
+                                struct wake_q_head *wqh,
+                                struct wake_q_head *wq_sleeper);
+
+extern void rt_mutex_postunlock(struct wake_q_head *wake_q,
+                               struct wake_q_head *wq_sleeper);
+
+/* RW semaphore special interface */
+struct ww_acquire_ctx;
+
+int __sched rt_mutex_slowlock_locked(struct rt_mutex *lock, int state,
+                                    struct hrtimer_sleeper *timeout,
+                                    enum rtmutex_chainwalk chwalk,
+                                    struct ww_acquire_ctx *ww_ctx,
+                                    struct rt_mutex_waiter *waiter);
 
 #ifdef CONFIG_DEBUG_RT_MUTEXES
 # include "rtmutex-debug.h"
diff --git a/kernel/locking/rwsem-rt.c b/kernel/locking/rwsem-rt.c
new file mode 100644 (file)
index 0000000..4a708ff
--- /dev/null
@@ -0,0 +1,268 @@
+/*
+ */
+#include <linux/rwsem.h>
+#include <linux/sched.h>
+#include <linux/export.h>
+
+#include "rtmutex_common.h"
+
+/*
+ * RT-specific reader/writer semaphores
+ *
+ * down_write()
+ *  1) Lock sem->rtmutex
+ *  2) Remove the reader BIAS to force readers into the slow path
+ *  3) Wait until all readers have left the critical region
+ *  4) Mark it write locked
+ *
+ * up_write()
+ *  1) Remove the write locked marker
+ *  2) Set the reader BIAS so readers can use the fast path again
+ *  3) Unlock sem->rtmutex to release blocked readers
+ *
+ * down_read()
+ *  1) Try fast path acquisition (reader BIAS is set)
+ *  2) Take sem->rtmutex.wait_lock which protects the writelocked flag
+ *  3) If !writelocked, acquire it for read
+ *  4) If writelocked, block on sem->rtmutex
+ *  5) unlock sem->rtmutex, goto 1)
+ *
+ * up_read()
+ *  1) Try fast path release (reader count != 1)
+ *  2) Wake the writer waiting in down_write()#3
+ *
+ * down_read()#3 has the consequence, that rw semaphores on RT are not writer
+ * fair, but writers, which should be avoided in RT tasks (think mmap_sem),
+ * are subject to the rtmutex priority/DL inheritance mechanism.
+ *
+ * It's possible to make the rw semaphores writer fair by keeping a list of
+ * active readers. A blocked writer would force all newly incoming readers to
+ * block on the rtmutex, but the rtmutex would have to be proxy locked for one
+ * reader after the other. We can't use multi-reader inheritance because there
+ * is no way to support that with SCHED_DEADLINE. Implementing the one by one
+ * reader boosting/handover mechanism is a major surgery for a very dubious
+ * value.
+ *
+ * The risk of writer starvation is there, but the pathological use cases
+ * which trigger it are not necessarily the typical RT workloads.
+ */
+
+void __rwsem_init(struct rw_semaphore *sem, const char *name,
+                 struct lock_class_key *key)
+{
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+       /*
+        * Make sure we are not reinitializing a held semaphore:
+        */
+       debug_check_no_locks_freed((void *)sem, sizeof(*sem));
+       lockdep_init_map(&sem->dep_map, name, key, 0);
+#endif
+       atomic_set(&sem->readers, READER_BIAS);
+}
+EXPORT_SYMBOL(__rwsem_init);
+
+int __down_read_trylock(struct rw_semaphore *sem)
+{
+       int r, old;
+
+       /*
+        * Increment reader count, if sem->readers < 0, i.e. READER_BIAS is
+        * set.
+        */
+       for (r = atomic_read(&sem->readers); r < 0;) {
+               old = atomic_cmpxchg(&sem->readers, r, r + 1);
+               if (likely(old == r))
+                       return 1;
+               r = old;
+       }
+       return 0;
+}
+
+void __sched __down_read(struct rw_semaphore *sem)
+{
+       struct rt_mutex *m = &sem->rtmutex;
+       struct rt_mutex_waiter waiter;
+
+       if (__down_read_trylock(sem))
+               return;
+
+       might_sleep();
+       raw_spin_lock_irq(&m->wait_lock);
+       /*
+        * Allow readers as long as the writer has not completely
+        * acquired the semaphore for write.
+        */
+       if (atomic_read(&sem->readers) != WRITER_BIAS) {
+               atomic_inc(&sem->readers);
+               raw_spin_unlock_irq(&m->wait_lock);
+               return;
+       }
+
+       /*
+        * Call into the slow lock path with the rtmutex->wait_lock
+        * held, so this can't result in the following race:
+        *
+        * Reader1              Reader2         Writer
+        *                      down_read()
+        *                                      down_write()
+        *                                      rtmutex_lock(m)
+        *                                      swait()
+        * down_read()
+        * unlock(m->wait_lock)
+        *                      up_read()
+        *                      swake()
+        *                                      lock(m->wait_lock)
+        *                                      sem->writelocked=true
+        *                                      unlock(m->wait_lock)
+        *
+        *                                      up_write()
+        *                                      sem->writelocked=false
+        *                                      rtmutex_unlock(m)
+        *                      down_read()
+        *                                      down_write()
+        *                                      rtmutex_lock(m)
+        *                                      swait()
+        * rtmutex_lock(m)
+        *
+        * That would put Reader1 behind the writer waiting on
+        * Reader2 to call up_read() which might be unbound.
+        */
+       rt_mutex_init_waiter(&waiter, false);
+       rt_mutex_slowlock_locked(m, TASK_UNINTERRUPTIBLE, NULL,
+                                RT_MUTEX_MIN_CHAINWALK, NULL,
+                                &waiter);
+       /*
+        * The slowlock() above is guaranteed to return with the rtmutex is
+        * now held, so there can't be a writer active. Increment the reader
+        * count and immediately drop the rtmutex again.
+        */
+       atomic_inc(&sem->readers);
+       raw_spin_unlock_irq(&m->wait_lock);
+       rt_mutex_unlock(m);
+
+       debug_rt_mutex_free_waiter(&waiter);
+}
+
+void __up_read(struct rw_semaphore *sem)
+{
+       struct rt_mutex *m = &sem->rtmutex;
+       struct task_struct *tsk;
+
+       /*
+        * sem->readers can only hit 0 when a writer is waiting for the
+        * active readers to leave the critical region.
+        */
+       if (!atomic_dec_and_test(&sem->readers))
+               return;
+
+       might_sleep();
+       raw_spin_lock_irq(&m->wait_lock);
+       /*
+        * Wake the writer, i.e. the rtmutex owner. It might release the
+        * rtmutex concurrently in the fast path (due to a signal), but to
+        * clean up the rwsem it needs to acquire m->wait_lock. The worst
+        * case which can happen is a spurious wakeup.
+        */
+       tsk = rt_mutex_owner(m);
+       if (tsk)
+               wake_up_process(tsk);
+
+       raw_spin_unlock_irq(&m->wait_lock);
+}
+
+static void __up_write_unlock(struct rw_semaphore *sem, int bias,
+                             unsigned long flags)
+{
+       struct rt_mutex *m = &sem->rtmutex;
+
+       atomic_add(READER_BIAS - bias, &sem->readers);
+       raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+       rt_mutex_unlock(m);
+}
+
+static int __sched __down_write_common(struct rw_semaphore *sem, int state)
+{
+       struct rt_mutex *m = &sem->rtmutex;
+       unsigned long flags;
+
+       /* Take the rtmutex as a first step */
+       if (rt_mutex_lock_state(m, state))
+               return -EINTR;
+
+       /* Force readers into slow path */
+       atomic_sub(READER_BIAS, &sem->readers);
+       might_sleep();
+
+       set_current_state(state);
+       for (;;) {
+               raw_spin_lock_irqsave(&m->wait_lock, flags);
+               /* Have all readers left the critical region? */
+               if (!atomic_read(&sem->readers)) {
+                       atomic_set(&sem->readers, WRITER_BIAS);
+                       __set_current_state(TASK_RUNNING);
+                       raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+                       return 0;
+               }
+
+               if (signal_pending_state(state, current)) {
+                       __set_current_state(TASK_RUNNING);
+                       __up_write_unlock(sem, 0, flags);
+                       return -EINTR;
+               }
+               raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+
+               if (atomic_read(&sem->readers) != 0) {
+                       schedule();
+                       set_current_state(state);
+               }
+       }
+}
+
+void __sched __down_write(struct rw_semaphore *sem)
+{
+       __down_write_common(sem, TASK_UNINTERRUPTIBLE);
+}
+
+int __sched __down_write_killable(struct rw_semaphore *sem)
+{
+       return __down_write_common(sem, TASK_KILLABLE);
+}
+
+int __down_write_trylock(struct rw_semaphore *sem)
+{
+       struct rt_mutex *m = &sem->rtmutex;
+       unsigned long flags;
+
+       if (!rt_mutex_trylock(m))
+               return 0;
+
+       atomic_sub(READER_BIAS, &sem->readers);
+
+       raw_spin_lock_irqsave(&m->wait_lock, flags);
+       if (!atomic_read(&sem->readers)) {
+               atomic_set(&sem->readers, WRITER_BIAS);
+               raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+               return 1;
+       }
+       __up_write_unlock(sem, 0, flags);
+       return 0;
+}
+
+void __up_write(struct rw_semaphore *sem)
+{
+       struct rt_mutex *m = &sem->rtmutex;
+       unsigned long flags;
+
+       raw_spin_lock_irqsave(&m->wait_lock, flags);
+       __up_write_unlock(sem, WRITER_BIAS, flags);
+}
+
+void __downgrade_write(struct rw_semaphore *sem)
+{
+       struct rt_mutex *m = &sem->rtmutex;
+       unsigned long flags;
+
+       raw_spin_lock_irqsave(&m->wait_lock, flags);
+       /* Release it and account current as reader */
+       __up_write_unlock(sem, WRITER_BIAS - 1, flags);
+}
index db3ccb1..9097796 100644 (file)
@@ -124,8 +124,11 @@ void __lockfunc __raw_##op##_lock_bh(locktype##_t *lock)           \
  *         __[spin|read|write]_lock_bh()
  */
 BUILD_LOCK_OPS(spin, raw_spinlock);
+
+#ifndef CONFIG_PREEMPT_RT_FULL
 BUILD_LOCK_OPS(read, rwlock);
 BUILD_LOCK_OPS(write, rwlock);
+#endif
 
 #endif
 
@@ -209,6 +212,8 @@ void __lockfunc _raw_spin_unlock_bh(raw_spinlock_t *lock)
 EXPORT_SYMBOL(_raw_spin_unlock_bh);
 #endif
 
+#ifndef CONFIG_PREEMPT_RT_FULL
+
 #ifndef CONFIG_INLINE_READ_TRYLOCK
 int __lockfunc _raw_read_trylock(rwlock_t *lock)
 {
@@ -353,6 +358,8 @@ void __lockfunc _raw_write_unlock_bh(rwlock_t *lock)
 EXPORT_SYMBOL(_raw_write_unlock_bh);
 #endif
 
+#endif /* !PREEMPT_RT_FULL */
+
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 
 void __lockfunc _raw_spin_lock_nested(raw_spinlock_t *lock, int subclass)
index 03595c2..d63df28 100644 (file)
@@ -31,6 +31,7 @@ void __raw_spin_lock_init(raw_spinlock_t *lock, const char *name,
 
 EXPORT_SYMBOL(__raw_spin_lock_init);
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 void __rwlock_init(rwlock_t *lock, const char *name,
                   struct lock_class_key *key)
 {
@@ -48,6 +49,7 @@ void __rwlock_init(rwlock_t *lock, const char *name,
 }
 
 EXPORT_SYMBOL(__rwlock_init);
+#endif
 
 static void spin_dump(raw_spinlock_t *lock, const char *msg)
 {
@@ -135,6 +137,7 @@ void do_raw_spin_unlock(raw_spinlock_t *lock)
        arch_spin_unlock(&lock->raw_lock);
 }
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 static void rwlock_bug(rwlock_t *lock, const char *msg)
 {
        if (!debug_locks_off())
@@ -224,3 +227,5 @@ void do_raw_write_unlock(rwlock_t *lock)
        debug_write_unlock(lock);
        arch_write_unlock(&lock->raw_lock);
 }
+
+#endif
index d86d169..866ad1d 100644 (file)
@@ -660,16 +660,7 @@ static void percpu_modcopy(struct module *mod,
                memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
 }
 
-/**
- * is_module_percpu_address - test whether address is from module static percpu
- * @addr: address to test
- *
- * Test whether @addr belongs to module static percpu area.
- *
- * RETURNS:
- * %true if @addr is from module static percpu area
- */
-bool is_module_percpu_address(unsigned long addr)
+bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
 {
        struct module *mod;
        unsigned int cpu;
@@ -683,9 +674,15 @@ bool is_module_percpu_address(unsigned long addr)
                        continue;
                for_each_possible_cpu(cpu) {
                        void *start = per_cpu_ptr(mod->percpu, cpu);
-
-                       if ((void *)addr >= start &&
-                           (void *)addr < start + mod->percpu_size) {
+                       void *va = (void *)addr;
+
+                       if (va >= start && va < start + mod->percpu_size) {
+                               if (can_addr) {
+                                       *can_addr = (unsigned long) (va - start);
+                                       *can_addr += (unsigned long)
+                                               per_cpu_ptr(mod->percpu,
+                                                           get_boot_cpu_id());
+                               }
                                preempt_enable();
                                return true;
                        }
@@ -696,6 +693,20 @@ bool is_module_percpu_address(unsigned long addr)
        return false;
 }
 
+/**
+ * is_module_percpu_address - test whether address is from module static percpu
+ * @addr: address to test
+ *
+ * Test whether @addr belongs to module static percpu area.
+ *
+ * RETURNS:
+ * %true if @addr is from module static percpu area
+ */
+bool is_module_percpu_address(unsigned long addr)
+{
+       return __is_module_percpu_address(addr, NULL);
+}
+
 #else /* ... !CONFIG_SMP */
 
 static inline void __percpu *mod_percpu(struct module *mod)
@@ -727,6 +738,11 @@ bool is_module_percpu_address(unsigned long addr)
        return false;
 }
 
+bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
+{
+       return false;
+}
+
 #endif /* CONFIG_SMP */
 
 #define MODINFO_ATTR(field)    \
index 1839b44..ec2c803 100644 (file)
@@ -493,9 +493,11 @@ static u64 oops_id;
 
 static int init_oops_id(void)
 {
+#ifndef CONFIG_PREEMPT_RT_FULL
        if (!oops_id)
                get_random_bytes(&oops_id, sizeof(oops_id));
        else
+#endif
                oops_id++;
 
        return 0;
index 7b393fa..18f3162 100644 (file)
@@ -291,6 +291,8 @@ static int create_image(int platform_mode)
 
        local_irq_disable();
 
+       system_state = SYSTEM_SUSPEND;
+
        error = syscore_suspend();
        if (error) {
                printk(KERN_ERR "PM: Some system devices failed to power down, "
@@ -322,6 +324,7 @@ static int create_image(int platform_mode)
        syscore_resume();
 
  Enable_irqs:
+       system_state = SYSTEM_RUNNING;
        local_irq_enable();
 
  Enable_cpus:
@@ -455,6 +458,7 @@ static int resume_target_kernel(bool platform_mode)
                goto Enable_cpus;
 
        local_irq_disable();
+       system_state = SYSTEM_SUSPEND;
 
        error = syscore_suspend();
        if (error)
@@ -488,6 +492,7 @@ static int resume_target_kernel(bool platform_mode)
        syscore_resume();
 
  Enable_irqs:
+       system_state = SYSTEM_RUNNING;
        local_irq_enable();
 
  Enable_cpus:
@@ -573,6 +578,7 @@ int hibernation_platform_enter(void)
                goto Enable_cpus;
 
        local_irq_disable();
+       system_state = SYSTEM_SUSPEND;
        syscore_suspend();
        if (pm_wakeup_pending()) {
                error = -EAGAIN;
@@ -585,6 +591,7 @@ int hibernation_platform_enter(void)
 
  Power_up:
        syscore_resume();
+       system_state = SYSTEM_RUNNING;
        local_irq_enable();
 
  Enable_cpus:
@@ -685,6 +692,10 @@ static int load_image_and_restore(void)
        return error;
 }
 
+#ifndef CONFIG_SUSPEND
+bool pm_in_action;
+#endif
+
 /**
  * hibernate - Carry out system hibernation, including saving the image.
  */
@@ -698,6 +709,8 @@ int hibernate(void)
                return -EPERM;
        }
 
+       pm_in_action = true;
+
        lock_system_sleep();
        /* The snapshot device should not be opened while we're running */
        if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
@@ -775,6 +788,7 @@ int hibernate(void)
        atomic_inc(&snapshot_device_available);
  Unlock:
        unlock_system_sleep();
+       pm_in_action = false;
        return error;
 }
 
index 71050f5..d8b1b9f 100644 (file)
@@ -421,6 +421,8 @@ static int suspend_enter(suspend_state_t state, bool *wakeup)
        arch_suspend_disable_irqs();
        BUG_ON(!irqs_disabled());
 
+       system_state = SYSTEM_SUSPEND;
+
        error = syscore_suspend();
        if (!error) {
                *wakeup = pm_wakeup_pending();
@@ -440,6 +442,8 @@ static int suspend_enter(suspend_state_t state, bool *wakeup)
                syscore_resume();
        }
 
+       system_state = SYSTEM_RUNNING;
+
        arch_suspend_enable_irqs();
        BUG_ON(irqs_disabled());
 
@@ -587,6 +591,8 @@ static int enter_state(suspend_state_t state)
        return error;
 }
 
+bool pm_in_action;
+
 static void pm_suspend_marker(char *annotation)
 {
        struct timespec ts;
@@ -613,6 +619,8 @@ int pm_suspend(suspend_state_t state)
        if (state <= PM_SUSPEND_ON || state >= PM_SUSPEND_MAX)
                return -EINVAL;
 
+       pm_in_action = true;
+
        pm_suspend_marker("entry");
        error = enter_state(state);
        if (error) {
@@ -622,6 +630,7 @@ int pm_suspend(suspend_state_t state)
                suspend_stats.success++;
        }
        pm_suspend_marker("exit");
+       pm_in_action = false;
        return error;
 }
 EXPORT_SYMBOL(pm_suspend);
index fa321b3..01cc148 100644 (file)
@@ -358,6 +358,65 @@ __packed __aligned(4)
  */
 DEFINE_RAW_SPINLOCK(logbuf_lock);
 
+#ifdef CONFIG_EARLY_PRINTK
+struct console *early_console;
+
+static void early_vprintk(const char *fmt, va_list ap)
+{
+       if (early_console) {
+               char buf[512];
+               int n = vscnprintf(buf, sizeof(buf), fmt, ap);
+
+               early_console->write(early_console, buf, n);
+       }
+}
+
+asmlinkage void early_printk(const char *fmt, ...)
+{
+       va_list ap;
+
+       va_start(ap, fmt);
+       early_vprintk(fmt, ap);
+       va_end(ap);
+}
+
+/*
+ * This is independent of any log levels - a global
+ * kill switch that turns off all of printk.
+ *
+ * Used by the NMI watchdog if early-printk is enabled.
+ */
+static bool __read_mostly printk_killswitch;
+
+static int __init force_early_printk_setup(char *str)
+{
+       printk_killswitch = true;
+       return 0;
+}
+early_param("force_early_printk", force_early_printk_setup);
+
+void printk_kill(void)
+{
+       printk_killswitch = true;
+}
+
+#ifdef CONFIG_PRINTK
+static int forced_early_printk(const char *fmt, va_list ap)
+{
+       if (!printk_killswitch)
+               return 0;
+       early_vprintk(fmt, ap);
+       return 1;
+}
+#endif
+
+#else
+static inline int forced_early_printk(const char *fmt, va_list ap)
+{
+       return 0;
+}
+#endif
+
 #ifdef CONFIG_PRINTK
 DECLARE_WAIT_QUEUE_HEAD(log_wait);
 #ifdef CONFIG_AMLOGIC_DRIVER
@@ -1333,6 +1392,7 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
 {
        char *text;
        int len = 0;
+       int attempts = 0;
 
        text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);
        if (!text)
@@ -1343,6 +1403,14 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
                u64 next_seq;
                u64 seq;
                u32 idx;
+               int num_msg;
+try_again:
+               attempts++;
+               if (attempts > 10) {
+                       len = -EBUSY;
+                       goto out;
+               }
+               num_msg = 0;
 
                /*
                 * Find first record that fits, including all following records,
@@ -1356,6 +1424,14 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
                        len += msg_print_text(msg, true, NULL, 0);
                        idx = log_next(idx);
                        seq++;
+                       num_msg++;
+                       if (num_msg > 5) {
+                               num_msg = 0;
+                               raw_spin_unlock_irq(&logbuf_lock);
+                               raw_spin_lock_irq(&logbuf_lock);
+                               if (clear_seq < log_first_seq)
+                                       goto try_again;
+                       }
                }
 
                /* move first record forward until length fits into the buffer */
@@ -1367,6 +1443,14 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
                        len -= msg_print_text(msg, true, NULL, 0);
                        idx = log_next(idx);
                        seq++;
+                       num_msg++;
+                       if (num_msg > 5) {
+                               num_msg = 0;
+                               raw_spin_unlock_irq(&logbuf_lock);
+                               raw_spin_lock_irq(&logbuf_lock);
+                               if (clear_seq < log_first_seq)
+                                       goto try_again;
+                       }
                }
 
                /* last message fitting into this dump */
@@ -1405,6 +1489,7 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
                clear_seq = log_next_seq;
                clear_idx = log_next_idx;
        }
+out:
        raw_spin_unlock_irq(&logbuf_lock);
 
        kfree(text);
@@ -1555,6 +1640,12 @@ static void call_console_drivers(int level,
        if (!console_drivers)
                return;
 
+       if (IS_ENABLED(CONFIG_PREEMPT_RT_BASE)) {
+               if (in_irq() || in_nmi())
+                       return;
+       }
+
+       migrate_disable();
        for_each_console(con) {
                if (exclusive_console && con != exclusive_console)
                        continue;
@@ -1570,6 +1661,7 @@ static void call_console_drivers(int level,
                else
                        con->write(con, text, len);
        }
+       migrate_enable();
 }
 
 /*
@@ -1773,6 +1865,13 @@ asmlinkage int vprintk_emit(int facility, int level,
        /* cpu currently holding logbuf_lock in this function */
        static unsigned int logbuf_cpu = UINT_MAX;
 
+       /*
+        * Fall back to early_printk if a debugging subsystem has
+        * killed printk output
+        */
+       if (unlikely(forced_early_printk(fmt, args)))
+               return 1;
+
        if (level == LOGLEVEL_SCHED) {
                level = LOGLEVEL_DEFAULT;
                in_sched = true;
@@ -1881,13 +1980,23 @@ asmlinkage int vprintk_emit(int facility, int level,
 
        /* If called from the scheduler, we can not call up(). */
        if (!in_sched) {
+               int may_trylock = 1;
+
                lockdep_off();
+#ifdef CONFIG_PREEMPT_RT_FULL
+               /*
+                * we can't take a sleeping lock with IRQs or preeption disabled
+                * so we can't print in these contexts
+                */
+               if (!(preempt_count() == 0 && !irqs_disabled()))
+                       may_trylock = 0;
+#endif
                /*
                 * Try to acquire and then immediately release the console
                 * semaphore.  The release will print out buffers and wake up
                 * /dev/kmsg and syslog() users.
                 */
-               if (console_trylock())
+               if (may_trylock && console_trylock())
                        console_unlock();
                lockdep_on();
        }
@@ -2008,26 +2117,6 @@ DEFINE_PER_CPU(printk_func_t, printk_func);
 
 #endif /* CONFIG_PRINTK */
 
-#ifdef CONFIG_EARLY_PRINTK
-struct console *early_console;
-
-asmlinkage __visible void early_printk(const char *fmt, ...)
-{
-       va_list ap;
-       char buf[512];
-       int n;
-
-       if (!early_console)
-               return;
-
-       va_start(ap, fmt);
-       n = vscnprintf(buf, sizeof(buf), fmt, ap);
-       va_end(ap);
-
-       early_console->write(early_console, buf, n);
-}
-#endif
-
 static int __add_preferred_console(char *name, int idx, char *options,
                                   char *brl_options)
 {
@@ -2300,11 +2389,16 @@ static void console_cont_flush(char *text, size_t size)
                goto out;
 
        len = cont_print_text(text, size);
+#ifdef CONFIG_PREEMPT_RT_FULL
+       raw_spin_unlock_irqrestore(&logbuf_lock, flags);
+       call_console_drivers(cont.level, NULL, 0, text, len);
+#else
        raw_spin_unlock(&logbuf_lock);
        stop_critical_timings();
        call_console_drivers(cont.level, NULL, 0, text, len);
        start_critical_timings();
        local_irq_restore(flags);
+#endif
        return;
 out:
        raw_spin_unlock_irqrestore(&logbuf_lock, flags);
@@ -2428,13 +2522,17 @@ skip:
                }
                console_idx = log_next(console_idx);
                console_seq++;
+#ifdef CONFIG_PREEMPT_RT_FULL
+               raw_spin_unlock_irqrestore(&logbuf_lock, flags);
+               call_console_drivers(level, ext_text, ext_len, text, len);
+#else
                raw_spin_unlock(&logbuf_lock);
 
                stop_critical_timings();        /* don't trace print latency */
                call_console_drivers(level, ext_text, ext_len, text, len);
                start_critical_timings();
                local_irq_restore(flags);
-
+#endif
                if (do_cond_resched)
                        cond_resched();
        }
@@ -2486,6 +2584,11 @@ void console_unblank(void)
 {
        struct console *c;
 
+       if (IS_ENABLED(CONFIG_PREEMPT_RT_BASE)) {
+               if (in_irq() || in_nmi())
+                       return;
+       }
+
        /*
         * console_unblank can no longer be called in interrupt context unless
         * oops_in_progress is set to 1..
index ea3370e..7245160 100644 (file)
@@ -170,7 +170,14 @@ static bool ptrace_freeze_traced(struct task_struct *task)
 
        spin_lock_irq(&task->sighand->siglock);
        if (task_is_traced(task) && !__fatal_signal_pending(task)) {
-               task->state = __TASK_TRACED;
+               unsigned long flags;
+
+               raw_spin_lock_irqsave(&task->pi_lock, flags);
+               if (task->state & __TASK_TRACED)
+                       task->state = __TASK_TRACED;
+               else
+                       task->saved_state = __TASK_TRACED;
+               raw_spin_unlock_irqrestore(&task->pi_lock, flags);
                ret = true;
        }
        spin_unlock_irq(&task->sighand->siglock);
index 5393bbc..91a105f 100644 (file)
@@ -404,6 +404,7 @@ static struct rcu_torture_ops rcu_ops = {
        .name           = "rcu"
 };
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 /*
  * Definitions for rcu_bh torture testing.
  */
@@ -443,6 +444,12 @@ static struct rcu_torture_ops rcu_bh_ops = {
        .name           = "rcu_bh"
 };
 
+#else
+static struct rcu_torture_ops rcu_bh_ops = {
+       .ttype          = INVALID_RCU_FLAVOR,
+};
+#endif
+
 /*
  * Don't even think about trying any of these in real life!!!
  * The names includes "busted", and they really means it!
index d0b113d..7c3b4c8 100644 (file)
 #include <linux/random.h>
 #include <linux/trace_events.h>
 #include <linux/suspend.h>
+#include <linux/delay.h>
+#include <linux/gfp.h>
+#include <linux/oom.h>
+#include <linux/smpboot.h>
+#include "../time/tick-internal.h"
 
 #include "tree.h"
 #include "rcu.h"
@@ -260,6 +265,19 @@ void rcu_sched_qs(void)
                           this_cpu_ptr(&rcu_sched_data), true);
 }
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+static void rcu_preempt_qs(void);
+
+void rcu_bh_qs(void)
+{
+       unsigned long flags;
+
+       /* Callers to this function, rcu_preempt_qs(), must disable irqs. */
+       local_irq_save(flags);
+       rcu_preempt_qs();
+       local_irq_restore(flags);
+}
+#else
 void rcu_bh_qs(void)
 {
        if (__this_cpu_read(rcu_bh_data.cpu_no_qs.s)) {
@@ -269,6 +287,7 @@ void rcu_bh_qs(void)
                __this_cpu_write(rcu_bh_data.cpu_no_qs.b.norm, false);
        }
 }
+#endif
 
 static DEFINE_PER_CPU(int, rcu_sched_qs_mask);
 
@@ -449,11 +468,13 @@ EXPORT_SYMBOL_GPL(rcu_batches_started_sched);
 /*
  * Return the number of RCU BH batches started thus far for debug & stats.
  */
+#ifndef CONFIG_PREEMPT_RT_FULL
 unsigned long rcu_batches_started_bh(void)
 {
        return rcu_bh_state.gpnum;
 }
 EXPORT_SYMBOL_GPL(rcu_batches_started_bh);
+#endif
 
 /*
  * Return the number of RCU batches completed thus far for debug & stats.
@@ -473,6 +494,7 @@ unsigned long rcu_batches_completed_sched(void)
 }
 EXPORT_SYMBOL_GPL(rcu_batches_completed_sched);
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 /*
  * Return the number of RCU BH batches completed thus far for debug & stats.
  */
@@ -481,6 +503,7 @@ unsigned long rcu_batches_completed_bh(void)
        return rcu_bh_state.completed;
 }
 EXPORT_SYMBOL_GPL(rcu_batches_completed_bh);
+#endif
 
 /*
  * Return the number of RCU expedited batches completed thus far for
@@ -504,6 +527,7 @@ unsigned long rcu_exp_batches_completed_sched(void)
 }
 EXPORT_SYMBOL_GPL(rcu_exp_batches_completed_sched);
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 /*
  * Force a quiescent state.
  */
@@ -522,6 +546,13 @@ void rcu_bh_force_quiescent_state(void)
 }
 EXPORT_SYMBOL_GPL(rcu_bh_force_quiescent_state);
 
+#else
+void rcu_force_quiescent_state(void)
+{
+}
+EXPORT_SYMBOL_GPL(rcu_force_quiescent_state);
+#endif
+
 /*
  * Force a quiescent state for RCU-sched.
  */
@@ -572,9 +603,11 @@ void rcutorture_get_gp_data(enum rcutorture_type test_type, int *flags,
        case RCU_FLAVOR:
                rsp = rcu_state_p;
                break;
+#ifndef CONFIG_PREEMPT_RT_FULL
        case RCU_BH_FLAVOR:
                rsp = &rcu_bh_state;
                break;
+#endif
        case RCU_SCHED_FLAVOR:
                rsp = &rcu_sched_state;
                break;
@@ -3034,18 +3067,17 @@ __rcu_process_callbacks(struct rcu_state *rsp)
 /*
  * Do RCU core processing for the current CPU.
  */
-static __latent_entropy void rcu_process_callbacks(struct softirq_action *unused)
+static __latent_entropy void rcu_process_callbacks(void)
 {
        struct rcu_state *rsp;
 
        if (cpu_is_offline(smp_processor_id()))
                return;
-       trace_rcu_utilization(TPS("Start RCU core"));
        for_each_rcu_flavor(rsp)
                __rcu_process_callbacks(rsp);
-       trace_rcu_utilization(TPS("End RCU core"));
 }
 
+static DEFINE_PER_CPU(struct task_struct *, rcu_cpu_kthread_task);
 /*
  * Schedule RCU callback invocation.  If the specified type of RCU
  * does not support RCU priority boosting, just do a direct call,
@@ -3057,20 +3089,107 @@ static void invoke_rcu_callbacks(struct rcu_state *rsp, struct rcu_data *rdp)
 {
        if (unlikely(!READ_ONCE(rcu_scheduler_fully_active)))
                return;
-       if (likely(!rsp->boost)) {
-               rcu_do_batch(rsp, rdp);
-               return;
-       }
-       invoke_rcu_callbacks_kthread();
+       rcu_do_batch(rsp, rdp);
+}
+
+static void rcu_wake_cond(struct task_struct *t, int status)
+{
+       /*
+        * If the thread is yielding, only wake it when this
+        * is invoked from idle
+        */
+       if (t && (status != RCU_KTHREAD_YIELDING || is_idle_task(current)))
+               wake_up_process(t);
 }
 
+/*
+ * Wake up this CPU's rcuc kthread to do RCU core processing.
+ */
 static void invoke_rcu_core(void)
 {
-       if (cpu_online(smp_processor_id()))
-               raise_softirq(RCU_SOFTIRQ);
+       unsigned long flags;
+       struct task_struct *t;
+
+       if (!cpu_online(smp_processor_id()))
+               return;
+       local_irq_save(flags);
+       __this_cpu_write(rcu_cpu_has_work, 1);
+       t = __this_cpu_read(rcu_cpu_kthread_task);
+       if (t != NULL && current != t)
+               rcu_wake_cond(t, __this_cpu_read(rcu_cpu_kthread_status));
+       local_irq_restore(flags);
+}
+
+static void rcu_cpu_kthread_park(unsigned int cpu)
+{
+       per_cpu(rcu_cpu_kthread_status, cpu) = RCU_KTHREAD_OFFCPU;
+}
+
+static int rcu_cpu_kthread_should_run(unsigned int cpu)
+{
+       return __this_cpu_read(rcu_cpu_has_work);
 }
 
 /*
+ * Per-CPU kernel thread that invokes RCU callbacks.  This replaces the
+ * RCU softirq used in flavors and configurations of RCU that do not
+ * support RCU priority boosting.
+ */
+static void rcu_cpu_kthread(unsigned int cpu)
+{
+       unsigned int *statusp = this_cpu_ptr(&rcu_cpu_kthread_status);
+       char work, *workp = this_cpu_ptr(&rcu_cpu_has_work);
+       int spincnt;
+
+       for (spincnt = 0; spincnt < 10; spincnt++) {
+               trace_rcu_utilization(TPS("Start CPU kthread@rcu_wait"));
+               local_bh_disable();
+               *statusp = RCU_KTHREAD_RUNNING;
+               this_cpu_inc(rcu_cpu_kthread_loops);
+               local_irq_disable();
+               work = *workp;
+               *workp = 0;
+               local_irq_enable();
+               if (work)
+                       rcu_process_callbacks();
+               local_bh_enable();
+               if (*workp == 0) {
+                       trace_rcu_utilization(TPS("End CPU kthread@rcu_wait"));
+                       *statusp = RCU_KTHREAD_WAITING;
+                       return;
+               }
+       }
+       *statusp = RCU_KTHREAD_YIELDING;
+       trace_rcu_utilization(TPS("Start CPU kthread@rcu_yield"));
+       schedule_timeout_interruptible(2);
+       trace_rcu_utilization(TPS("End CPU kthread@rcu_yield"));
+       *statusp = RCU_KTHREAD_WAITING;
+}
+
+static struct smp_hotplug_thread rcu_cpu_thread_spec = {
+       .store                  = &rcu_cpu_kthread_task,
+       .thread_should_run      = rcu_cpu_kthread_should_run,
+       .thread_fn              = rcu_cpu_kthread,
+       .thread_comm            = "rcuc/%u",
+       .setup                  = rcu_cpu_kthread_setup,
+       .park                   = rcu_cpu_kthread_park,
+};
+
+/*
+ * Spawn per-CPU RCU core processing kthreads.
+ */
+static int __init rcu_spawn_core_kthreads(void)
+{
+       int cpu;
+
+       for_each_possible_cpu(cpu)
+               per_cpu(rcu_cpu_has_work, cpu) = 0;
+       BUG_ON(smpboot_register_percpu_thread(&rcu_cpu_thread_spec));
+       return 0;
+}
+early_initcall(rcu_spawn_core_kthreads);
+
+/*
  * Handle any core-RCU processing required by a call_rcu() invocation.
  */
 static void __call_rcu_core(struct rcu_state *rsp, struct rcu_data *rdp,
@@ -3213,6 +3332,7 @@ void call_rcu_sched(struct rcu_head *head, rcu_callback_t func)
 }
 EXPORT_SYMBOL_GPL(call_rcu_sched);
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 /*
  * Queue an RCU callback for invocation after a quicker grace period.
  */
@@ -3221,6 +3341,7 @@ void call_rcu_bh(struct rcu_head *head, rcu_callback_t func)
        __call_rcu(head, func, &rcu_bh_state, -1, 0);
 }
 EXPORT_SYMBOL_GPL(call_rcu_bh);
+#endif
 
 /*
  * Queue an RCU callback for lazy invocation after a grace period.
@@ -3312,6 +3433,7 @@ void synchronize_sched(void)
 }
 EXPORT_SYMBOL_GPL(synchronize_sched);
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 /**
  * synchronize_rcu_bh - wait until an rcu_bh grace period has elapsed.
  *
@@ -3338,6 +3460,7 @@ void synchronize_rcu_bh(void)
                wait_rcu_gp(call_rcu_bh);
 }
 EXPORT_SYMBOL_GPL(synchronize_rcu_bh);
+#endif
 
 /**
  * get_state_synchronize_rcu - Snapshot current RCU state
@@ -3716,6 +3839,7 @@ static void _rcu_barrier(struct rcu_state *rsp)
        mutex_unlock(&rsp->barrier_mutex);
 }
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 /**
  * rcu_barrier_bh - Wait until all in-flight call_rcu_bh() callbacks complete.
  */
@@ -3724,6 +3848,7 @@ void rcu_barrier_bh(void)
        _rcu_barrier(&rcu_bh_state);
 }
 EXPORT_SYMBOL_GPL(rcu_barrier_bh);
+#endif
 
 /**
  * rcu_barrier_sched - Wait for in-flight call_rcu_sched() callbacks.
@@ -4245,12 +4370,13 @@ void __init rcu_init(void)
 
        rcu_bootup_announce();
        rcu_init_geometry();
+#ifndef CONFIG_PREEMPT_RT_FULL
        rcu_init_one(&rcu_bh_state);
+#endif
        rcu_init_one(&rcu_sched_state);
        if (dump_tree)
                rcu_dump_rcu_node_tree(&rcu_sched_state);
        __rcu_init_preempt();
-       open_softirq(RCU_SOFTIRQ, rcu_process_callbacks);
 
        /*
         * We don't need protection against CPU-hotplug here because
index e99a523..958ac10 100644 (file)
@@ -588,18 +588,18 @@ extern struct list_head rcu_struct_flavors;
  */
 extern struct rcu_state rcu_sched_state;
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 extern struct rcu_state rcu_bh_state;
+#endif
 
 #ifdef CONFIG_PREEMPT_RCU
 extern struct rcu_state rcu_preempt_state;
 #endif /* #ifdef CONFIG_PREEMPT_RCU */
 
-#ifdef CONFIG_RCU_BOOST
 DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
 DECLARE_PER_CPU(int, rcu_cpu_kthread_cpu);
 DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
 DECLARE_PER_CPU(char, rcu_cpu_has_work);
-#endif /* #ifdef CONFIG_RCU_BOOST */
 
 #ifndef RCU_TREE_NONCORE
 
@@ -619,10 +619,9 @@ void call_rcu(struct rcu_head *head, rcu_callback_t func);
 static void __init __rcu_init_preempt(void);
 static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags);
 static void rcu_preempt_boost_start_gp(struct rcu_node *rnp);
-static void invoke_rcu_callbacks_kthread(void);
 static bool rcu_is_callbacks_kthread(void);
+static void rcu_cpu_kthread_setup(unsigned int cpu);
 #ifdef CONFIG_RCU_BOOST
-static void rcu_preempt_do_callbacks(void);
 static int rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
                                                 struct rcu_node *rnp);
 #endif /* #ifdef CONFIG_RCU_BOOST */
index 554ea54..510de72 100644 (file)
  *        Paul E. McKenney <paulmck@linux.vnet.ibm.com>
  */
 
-#include <linux/delay.h>
-#include <linux/gfp.h>
-#include <linux/oom.h>
-#include <linux/smpboot.h>
-#include "../time/tick-internal.h"
-
 #ifdef CONFIG_RCU_BOOST
 
 #include "../locking/rtmutex_common.h"
 
-/*
- * Control variables for per-CPU and per-rcu_node kthreads.  These
- * handle all flavors of RCU.
- */
-static DEFINE_PER_CPU(struct task_struct *, rcu_cpu_kthread_task);
-DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
-DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
-DEFINE_PER_CPU(char, rcu_cpu_has_work);
-
 #else /* #ifdef CONFIG_RCU_BOOST */
 
 /*
@@ -52,9 +37,18 @@ DEFINE_PER_CPU(char, rcu_cpu_has_work);
  * This probably needs to be excluded from -rt builds.
  */
 #define rt_mutex_owner(a) ({ WARN_ON_ONCE(1); NULL; })
+#define rt_mutex_futex_unlock(x) WARN_ON_ONCE(1)
 
 #endif /* #else #ifdef CONFIG_RCU_BOOST */
 
+/*
+ * Control variables for per-CPU and per-rcu_node kthreads.  These
+ * handle all flavors of RCU.
+ */
+DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
+DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
+DEFINE_PER_CPU(char, rcu_cpu_has_work);
+
 #ifdef CONFIG_RCU_NOCB_CPU
 static cpumask_var_t rcu_nocb_mask; /* CPUs to have callbacks offloaded. */
 static bool have_rcu_nocb_mask;            /* Was rcu_nocb_mask allocated? */
@@ -426,7 +420,7 @@ void rcu_read_unlock_special(struct task_struct *t)
        }
 
        /* Hardware IRQ handlers cannot block, complain if they get here. */
-       if (in_irq() || in_serving_softirq()) {
+       if (preempt_count() & (HARDIRQ_MASK | SOFTIRQ_OFFSET)) {
                lockdep_rcu_suspicious(__FILE__, __LINE__,
                                       "rcu_read_unlock() from irq or softirq with blocking in critical section!!!\n");
                pr_alert("->rcu_read_unlock_special: %#x (b: %d, enq: %d nq: %d)\n",
@@ -492,7 +486,7 @@ void rcu_read_unlock_special(struct task_struct *t)
 
                /* Unboost if we were boosted. */
                if (IS_ENABLED(CONFIG_RCU_BOOST) && drop_boost_mutex)
-                       rt_mutex_unlock(&rnp->boost_mtx);
+                       rt_mutex_futex_unlock(&rnp->boost_mtx);
 
                /*
                 * If this was the last task on the expedited lists,
@@ -638,15 +632,6 @@ static void rcu_preempt_check_callbacks(void)
                t->rcu_read_unlock_special.b.need_qs = true;
 }
 
-#ifdef CONFIG_RCU_BOOST
-
-static void rcu_preempt_do_callbacks(void)
-{
-       rcu_do_batch(rcu_state_p, this_cpu_ptr(rcu_data_p));
-}
-
-#endif /* #ifdef CONFIG_RCU_BOOST */
-
 /*
  * Queue a preemptible-RCU callback for invocation after a grace period.
  */
@@ -835,9 +820,20 @@ void exit_rcu(void)
 
 #endif /* #else #ifdef CONFIG_PREEMPT_RCU */
 
+/*
+ * If boosting, set rcuc kthreads to realtime priority.
+ */
+static void rcu_cpu_kthread_setup(unsigned int cpu)
+{
 #ifdef CONFIG_RCU_BOOST
+       struct sched_param sp;
 
-#include "../locking/rtmutex_common.h"
+       sp.sched_priority = kthread_prio;
+       sched_setscheduler_nocheck(current, SCHED_FIFO, &sp);
+#endif /* #ifdef CONFIG_RCU_BOOST */
+}
+
+#ifdef CONFIG_RCU_BOOST
 
 #ifdef CONFIG_RCU_TRACE
 
@@ -866,16 +862,6 @@ static void rcu_initiate_boost_trace(struct rcu_node *rnp)
 
 #endif /* #else #ifdef CONFIG_RCU_TRACE */
 
-static void rcu_wake_cond(struct task_struct *t, int status)
-{
-       /*
-        * If the thread is yielding, only wake it when this
-        * is invoked from idle
-        */
-       if (status != RCU_KTHREAD_YIELDING || is_idle_task(current))
-               wake_up_process(t);
-}
-
 /*
  * Carry out RCU priority boosting on the task indicated by ->exp_tasks
  * or ->boost_tasks, advancing the pointer to the next task in the
@@ -1019,23 +1005,6 @@ static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags)
 }
 
 /*
- * Wake up the per-CPU kthread to invoke RCU callbacks.
- */
-static void invoke_rcu_callbacks_kthread(void)
-{
-       unsigned long flags;
-
-       local_irq_save(flags);
-       __this_cpu_write(rcu_cpu_has_work, 1);
-       if (__this_cpu_read(rcu_cpu_kthread_task) != NULL &&
-           current != __this_cpu_read(rcu_cpu_kthread_task)) {
-               rcu_wake_cond(__this_cpu_read(rcu_cpu_kthread_task),
-                             __this_cpu_read(rcu_cpu_kthread_status));
-       }
-       local_irq_restore(flags);
-}
-
-/*
  * Is the current CPU running the RCU-callbacks kthread?
  * Caller must have preemption disabled.
  */
@@ -1089,67 +1058,6 @@ static int rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
        return 0;
 }
 
-static void rcu_kthread_do_work(void)
-{
-       rcu_do_batch(&rcu_sched_state, this_cpu_ptr(&rcu_sched_data));
-       rcu_do_batch(&rcu_bh_state, this_cpu_ptr(&rcu_bh_data));
-       rcu_preempt_do_callbacks();
-}
-
-static void rcu_cpu_kthread_setup(unsigned int cpu)
-{
-       struct sched_param sp;
-
-       sp.sched_priority = kthread_prio;
-       sched_setscheduler_nocheck(current, SCHED_FIFO, &sp);
-}
-
-static void rcu_cpu_kthread_park(unsigned int cpu)
-{
-       per_cpu(rcu_cpu_kthread_status, cpu) = RCU_KTHREAD_OFFCPU;
-}
-
-static int rcu_cpu_kthread_should_run(unsigned int cpu)
-{
-       return __this_cpu_read(rcu_cpu_has_work);
-}
-
-/*
- * Per-CPU kernel thread that invokes RCU callbacks.  This replaces the
- * RCU softirq used in flavors and configurations of RCU that do not
- * support RCU priority boosting.
- */
-static void rcu_cpu_kthread(unsigned int cpu)
-{
-       unsigned int *statusp = this_cpu_ptr(&rcu_cpu_kthread_status);
-       char work, *workp = this_cpu_ptr(&rcu_cpu_has_work);
-       int spincnt;
-
-       for (spincnt = 0; spincnt < 10; spincnt++) {
-               trace_rcu_utilization(TPS("Start CPU kthread@rcu_wait"));
-               local_bh_disable();
-               *statusp = RCU_KTHREAD_RUNNING;
-               this_cpu_inc(rcu_cpu_kthread_loops);
-               local_irq_disable();
-               work = *workp;
-               *workp = 0;
-               local_irq_enable();
-               if (work)
-                       rcu_kthread_do_work();
-               local_bh_enable();
-               if (*workp == 0) {
-                       trace_rcu_utilization(TPS("End CPU kthread@rcu_wait"));
-                       *statusp = RCU_KTHREAD_WAITING;
-                       return;
-               }
-       }
-       *statusp = RCU_KTHREAD_YIELDING;
-       trace_rcu_utilization(TPS("Start CPU kthread@rcu_yield"));
-       schedule_timeout_interruptible(2);
-       trace_rcu_utilization(TPS("End CPU kthread@rcu_yield"));
-       *statusp = RCU_KTHREAD_WAITING;
-}
-
 /*
  * Set the per-rcu_node kthread's affinity to cover all CPUs that are
  * served by the rcu_node in question.  The CPU hotplug lock is still
@@ -1180,26 +1088,12 @@ static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu)
        free_cpumask_var(cm);
 }
 
-static struct smp_hotplug_thread rcu_cpu_thread_spec = {
-       .store                  = &rcu_cpu_kthread_task,
-       .thread_should_run      = rcu_cpu_kthread_should_run,
-       .thread_fn              = rcu_cpu_kthread,
-       .thread_comm            = "rcuc/%u",
-       .setup                  = rcu_cpu_kthread_setup,
-       .park                   = rcu_cpu_kthread_park,
-};
-
 /*
  * Spawn boost kthreads -- called as soon as the scheduler is running.
  */
 static void __init rcu_spawn_boost_kthreads(void)
 {
        struct rcu_node *rnp;
-       int cpu;
-
-       for_each_possible_cpu(cpu)
-               per_cpu(rcu_cpu_has_work, cpu) = 0;
-       BUG_ON(smpboot_register_percpu_thread(&rcu_cpu_thread_spec));
        rcu_for_each_leaf_node(rcu_state_p, rnp)
                (void)rcu_spawn_one_boost_kthread(rcu_state_p, rnp);
 }
@@ -1222,11 +1116,6 @@ static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags)
        raw_spin_unlock_irqrestore_rcu_node(rnp, flags);
 }
 
-static void invoke_rcu_callbacks_kthread(void)
-{
-       WARN_ON_ONCE(1);
-}
-
 static bool rcu_is_callbacks_kthread(void)
 {
        return false;
@@ -1250,7 +1139,7 @@ static void rcu_prepare_kthreads(int cpu)
 
 #endif /* #else #ifdef CONFIG_RCU_BOOST */
 
-#if !defined(CONFIG_RCU_FAST_NO_HZ)
+#if !defined(CONFIG_RCU_FAST_NO_HZ) || defined(CONFIG_PREEMPT_RT_FULL)
 
 /*
  * Check to see if any future RCU-related work will need to be done
@@ -1267,7 +1156,9 @@ int rcu_needs_cpu(u64 basemono, u64 *nextevt)
        return IS_ENABLED(CONFIG_RCU_NOCB_CPU_ALL)
               ? 0 : rcu_cpu_has_callbacks(NULL);
 }
+#endif /* !defined(CONFIG_RCU_FAST_NO_HZ) || defined(CONFIG_PREEMPT_RT_FULL) */
 
+#if !defined(CONFIG_RCU_FAST_NO_HZ)
 /*
  * Because we do not have RCU_FAST_NO_HZ, don't bother cleaning up
  * after it.
@@ -1363,6 +1254,8 @@ static bool __maybe_unused rcu_try_advance_all_cbs(void)
        return cbs_ready;
 }
 
+#ifndef CONFIG_PREEMPT_RT_FULL
+
 /*
  * Allow the CPU to enter dyntick-idle mode unless it has callbacks ready
  * to invoke.  If the CPU has callbacks, try to advance them.  Tell the
@@ -1408,6 +1301,7 @@ int rcu_needs_cpu(u64 basemono, u64 *nextevt)
        *nextevt = basemono + dj * TICK_NSEC;
        return 0;
 }
+#endif /* #ifndef CONFIG_PREEMPT_RT_FULL */
 
 /*
  * Prepare a CPU for idle from an RCU perspective.  The first major task
index 4f6db7e..ee02e1e 100644 (file)
@@ -62,7 +62,7 @@
 #ifndef CONFIG_TINY_RCU
 module_param(rcu_expedited, int, 0);
 module_param(rcu_normal, int, 0);
-static int rcu_normal_after_boot;
+static int rcu_normal_after_boot = IS_ENABLED(CONFIG_PREEMPT_RT_FULL);
 module_param(rcu_normal_after_boot, int, 0);
 #endif /* #ifndef CONFIG_TINY_RCU */
 
@@ -132,8 +132,7 @@ bool rcu_gp_is_normal(void)
 }
 EXPORT_SYMBOL_GPL(rcu_gp_is_normal);
 
-static atomic_t rcu_expedited_nesting =
-       ATOMIC_INIT(IS_ENABLED(CONFIG_RCU_EXPEDITE_BOOT) ? 1 : 0);
+static atomic_t rcu_expedited_nesting =        ATOMIC_INIT(1);
 
 /*
  * Should normal grace-period primitives be expedited?  Intended for
@@ -182,8 +181,7 @@ EXPORT_SYMBOL_GPL(rcu_unexpedite_gp);
  */
 void rcu_end_inkernel_boot(void)
 {
-       if (IS_ENABLED(CONFIG_RCU_EXPEDITE_BOOT))
-               rcu_unexpedite_gp();
+       rcu_unexpedite_gp();
        if (rcu_normal_after_boot)
                WRITE_ONCE(rcu_normal, 1);
 }
@@ -298,6 +296,7 @@ int rcu_read_lock_held(void)
 }
 EXPORT_SYMBOL_GPL(rcu_read_lock_held);
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 /**
  * rcu_read_lock_bh_held() - might we be in RCU-bh read-side critical section?
  *
@@ -324,6 +323,7 @@ int rcu_read_lock_bh_held(void)
        return in_softirq() || irqs_disabled();
 }
 EXPORT_SYMBOL_GPL(rcu_read_lock_bh_held);
+#endif
 
 #endif /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */
 
index c9dbe93..82eb026 100644 (file)
@@ -17,7 +17,7 @@ endif
 
 obj-y += core.o loadavg.o clock.o cputime.o
 obj-y += idle_task.o fair.o rt.o deadline.o stop_task.o
-obj-y += wait.o swait.o completion.o idle.o
+obj-y += wait.o swait.o swork.o completion.o idle.o
 obj-$(CONFIG_SMP) += cpupri.o cpudeadline.o energy.o
 obj-$(CONFIG_SCHED_WALT) += walt.o
 obj-$(CONFIG_SCHED_AUTOGROUP) += auto_group.o
index 8d0f35d..b62cf64 100644 (file)
@@ -30,10 +30,10 @@ void complete(struct completion *x)
 {
        unsigned long flags;
 
-       spin_lock_irqsave(&x->wait.lock, flags);
+       raw_spin_lock_irqsave(&x->wait.lock, flags);
        x->done++;
-       __wake_up_locked(&x->wait, TASK_NORMAL, 1);
-       spin_unlock_irqrestore(&x->wait.lock, flags);
+       swake_up_locked(&x->wait);
+       raw_spin_unlock_irqrestore(&x->wait.lock, flags);
 }
 EXPORT_SYMBOL(complete);
 
@@ -50,10 +50,10 @@ void complete_all(struct completion *x)
 {
        unsigned long flags;
 
-       spin_lock_irqsave(&x->wait.lock, flags);
+       raw_spin_lock_irqsave(&x->wait.lock, flags);
        x->done += UINT_MAX/2;
-       __wake_up_locked(&x->wait, TASK_NORMAL, 0);
-       spin_unlock_irqrestore(&x->wait.lock, flags);
+       swake_up_all_locked(&x->wait);
+       raw_spin_unlock_irqrestore(&x->wait.lock, flags);
 }
 EXPORT_SYMBOL(complete_all);
 
@@ -62,20 +62,20 @@ do_wait_for_common(struct completion *x,
                   long (*action)(long), long timeout, int state)
 {
        if (!x->done) {
-               DECLARE_WAITQUEUE(wait, current);
+               DECLARE_SWAITQUEUE(wait);
 
-               __add_wait_queue_tail_exclusive(&x->wait, &wait);
+               __prepare_to_swait(&x->wait, &wait);
                do {
                        if (signal_pending_state(state, current)) {
                                timeout = -ERESTARTSYS;
                                break;
                        }
                        __set_current_state(state);
-                       spin_unlock_irq(&x->wait.lock);
+                       raw_spin_unlock_irq(&x->wait.lock);
                        timeout = action(timeout);
-                       spin_lock_irq(&x->wait.lock);
+                       raw_spin_lock_irq(&x->wait.lock);
                } while (!x->done && timeout);
-               __remove_wait_queue(&x->wait, &wait);
+               __finish_swait(&x->wait, &wait);
                if (!x->done)
                        return timeout;
        }
@@ -89,9 +89,9 @@ __wait_for_common(struct completion *x,
 {
        might_sleep();
 
-       spin_lock_irq(&x->wait.lock);
+       raw_spin_lock_irq(&x->wait.lock);
        timeout = do_wait_for_common(x, action, timeout, state);
-       spin_unlock_irq(&x->wait.lock);
+       raw_spin_unlock_irq(&x->wait.lock);
        return timeout;
 }
 
@@ -277,12 +277,12 @@ bool try_wait_for_completion(struct completion *x)
        if (!READ_ONCE(x->done))
                return 0;
 
-       spin_lock_irqsave(&x->wait.lock, flags);
+       raw_spin_lock_irqsave(&x->wait.lock, flags);
        if (!x->done)
                ret = 0;
        else
                x->done--;
-       spin_unlock_irqrestore(&x->wait.lock, flags);
+       raw_spin_unlock_irqrestore(&x->wait.lock, flags);
        return ret;
 }
 EXPORT_SYMBOL(try_wait_for_completion);
@@ -311,7 +311,7 @@ bool completion_done(struct completion *x)
         * after it's acquired the lock.
         */
        smp_rmb();
-       spin_unlock_wait(&x->wait.lock);
+       raw_spin_unlock_wait(&x->wait.lock);
        return true;
 }
 EXPORT_SYMBOL(completion_done);
index 917ae93..caac2f5 100644 (file)
@@ -131,7 +131,11 @@ const_debug unsigned int sysctl_sched_features =
  * Number of tasks to iterate in a single balance run.
  * Limited because this is done with IRQs disabled.
  */
+#ifndef CONFIG_PREEMPT_RT_FULL
 const_debug unsigned int sysctl_sched_nr_migrate = 32;
+#else
+const_debug unsigned int sysctl_sched_nr_migrate = 8;
+#endif
 
 /*
  * period over which we average the RT time consumption, measured
@@ -359,6 +363,7 @@ static void init_rq_hrtick(struct rq *rq)
 
        hrtimer_init(&rq->hrtick_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
        rq->hrtick_timer.function = hrtick;
+       rq->hrtick_timer.irqsafe = 1;
 }
 #else  /* CONFIG_SCHED_HRTICK */
 static inline void hrtick_clear(struct rq *rq)
@@ -439,9 +444,15 @@ static bool set_nr_if_polling(struct task_struct *p)
 #endif
 #endif
 
-void wake_q_add(struct wake_q_head *head, struct task_struct *task)
+void __wake_q_add(struct wake_q_head *head, struct task_struct *task,
+                 bool sleeper)
 {
-       struct wake_q_node *node = &task->wake_q;
+       struct wake_q_node *node;
+
+       if (sleeper)
+               node = &task->wake_q_sleeper;
+       else
+               node = &task->wake_q;
 
        /*
         * Atomically grab the task, if ->wake_q is !nil already it means
@@ -463,24 +474,33 @@ void wake_q_add(struct wake_q_head *head, struct task_struct *task)
        head->lastp = &node->next;
 }
 
-void wake_up_q(struct wake_q_head *head)
+void __wake_up_q(struct wake_q_head *head, bool sleeper)
 {
        struct wake_q_node *node = head->first;
 
        while (node != WAKE_Q_TAIL) {
                struct task_struct *task;
 
-               task = container_of(node, struct task_struct, wake_q);
+               if (sleeper)
+                       task = container_of(node, struct task_struct, wake_q_sleeper);
+               else
+                       task = container_of(node, struct task_struct, wake_q);
                BUG_ON(!task);
                /* task can safely be re-inserted now */
                node = node->next;
-               task->wake_q.next = NULL;
+               if (sleeper)
+                       task->wake_q_sleeper.next = NULL;
+               else
+                       task->wake_q.next = NULL;
 
                /*
                 * wake_up_process() implies a wmb() to pair with the queueing
                 * in wake_q_add() so as not to miss wakeups.
                 */
-               wake_up_process(task);
+               if (sleeper)
+                       wake_up_lock_sleeper(task);
+               else
+                       wake_up_process(task);
                put_task_struct(task);
        }
 }
@@ -516,6 +536,38 @@ void resched_curr(struct rq *rq)
                trace_sched_wake_idle_without_ipi(cpu);
 }
 
+#ifdef CONFIG_PREEMPT_LAZY
+void resched_curr_lazy(struct rq *rq)
+{
+       struct task_struct *curr = rq->curr;
+       int cpu;
+
+       if (!sched_feat(PREEMPT_LAZY)) {
+               resched_curr(rq);
+               return;
+       }
+
+       lockdep_assert_held(&rq->lock);
+
+       if (test_tsk_need_resched(curr))
+               return;
+
+       if (test_tsk_need_resched_lazy(curr))
+               return;
+
+       set_tsk_need_resched_lazy(curr);
+
+       cpu = cpu_of(rq);
+       if (cpu == smp_processor_id())
+               return;
+
+       /* NEED_RESCHED_LAZY must be visible before we test polling */
+       smp_mb();
+       if (!tsk_is_polling(curr))
+               smp_send_reschedule(cpu);
+}
+#endif
+
 void resched_cpu(int cpu)
 {
        struct rq *rq = cpu_rq(cpu);
@@ -539,11 +591,14 @@ void resched_cpu(int cpu)
  */
 int get_nohz_timer_target(void)
 {
-       int i, cpu = smp_processor_id();
+       int i, cpu;
        struct sched_domain *sd;
 
+       preempt_disable_rt();
+       cpu = smp_processor_id();
+
        if (!idle_cpu(cpu) && is_housekeeping_cpu(cpu))
-               return cpu;
+               goto preempt_en_rt;
 
        rcu_read_lock();
        for_each_domain(cpu, sd) {
@@ -562,6 +617,8 @@ int get_nohz_timer_target(void)
                cpu = housekeeping_any_cpu();
 unlock:
        rcu_read_unlock();
+preempt_en_rt:
+       preempt_enable_rt();
        return cpu;
 }
 /*
@@ -1109,7 +1166,8 @@ void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_ma
        p->nr_cpus_allowed = cpumask_weight(new_mask);
 }
 
-void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
+static void __do_set_cpus_allowed_tail(struct task_struct *p,
+                                      const struct cpumask *new_mask)
 {
        struct rq *rq = task_rq(p);
        bool queued, running;
@@ -1138,6 +1196,98 @@ void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
                set_curr_task(rq, p);
 }
 
+void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
+{
+       if (__migrate_disabled(p)) {
+               lockdep_assert_held(&p->pi_lock);
+
+               cpumask_copy(&p->cpus_allowed, new_mask);
+#if defined(CONFIG_PREEMPT_RT_FULL) && defined(CONFIG_SMP)
+               p->migrate_disable_update = 1;
+#endif
+               return;
+       }
+       __do_set_cpus_allowed_tail(p, new_mask);
+}
+
+static DEFINE_PER_CPU(struct cpumask, sched_cpumasks);
+static DEFINE_MUTEX(sched_down_mutex);
+static cpumask_t sched_down_cpumask;
+
+void tell_sched_cpu_down_begin(int cpu)
+{
+       mutex_lock(&sched_down_mutex);
+       cpumask_set_cpu(cpu, &sched_down_cpumask);
+       mutex_unlock(&sched_down_mutex);
+}
+
+void tell_sched_cpu_down_done(int cpu)
+{
+       mutex_lock(&sched_down_mutex);
+       cpumask_clear_cpu(cpu, &sched_down_cpumask);
+       mutex_unlock(&sched_down_mutex);
+}
+
+/**
+ * migrate_me - try to move the current task off this cpu
+ *
+ * Used by the pin_current_cpu() code to try to get tasks
+ * to move off the current CPU as it is going down.
+ * It will only move the task if the task isn't pinned to
+ * the CPU (with migrate_disable, affinity or NO_SETAFFINITY)
+ * and the task has to be in a RUNNING state. Otherwise the
+ * movement of the task will wake it up (change its state
+ * to running) when the task did not expect it.
+ *
+ * Returns 1 if it succeeded in moving the current task
+ *         0 otherwise.
+ */
+int migrate_me(void)
+{
+       struct task_struct *p = current;
+       struct migration_arg arg;
+       struct cpumask *cpumask;
+       struct cpumask *mask;
+       unsigned int dest_cpu;
+       struct rq_flags rf;
+       struct rq *rq;
+
+       /*
+        * We can not migrate tasks bounded to a CPU or tasks not
+        * running. The movement of the task will wake it up.
+        */
+       if (p->flags & PF_NO_SETAFFINITY || p->state)
+               return 0;
+
+       mutex_lock(&sched_down_mutex);
+       rq = task_rq_lock(p, &rf);
+
+       cpumask = this_cpu_ptr(&sched_cpumasks);
+       mask = &p->cpus_allowed;
+
+       cpumask_andnot(cpumask, mask, &sched_down_cpumask);
+
+       if (!cpumask_weight(cpumask)) {
+               /* It's only on this CPU? */
+               task_rq_unlock(rq, p, &rf);
+               mutex_unlock(&sched_down_mutex);
+               return 0;
+       }
+
+       dest_cpu = cpumask_any_and(cpu_active_mask, cpumask);
+
+       arg.task = p;
+       arg.dest_cpu = dest_cpu;
+
+       task_rq_unlock(rq, p, &rf);
+
+       stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg);
+       tlb_migrate_finish(p->mm);
+       mutex_unlock(&sched_down_mutex);
+
+       return 1;
+}
+
 /*
  * Change a given task's CPU affinity. Migrate the thread to a
  * proper CPU and schedule it away if the CPU it's executing on
@@ -1197,7 +1347,7 @@ static int __set_cpus_allowed_ptr(struct task_struct *p,
        }
 
        /* Can the task run on the task's current CPU? If so, we're done */
-       if (cpumask_test_cpu(task_cpu(p), new_mask))
+       if (cpumask_test_cpu(task_cpu(p), new_mask) || __migrate_disabled(p))
                goto out;
 
        if (task_running(rq, p) || p->state == TASK_WAKING) {
@@ -1387,6 +1537,18 @@ out:
        return ret;
 }
 
+static bool check_task_state(struct task_struct *p, long match_state)
+{
+       bool match = false;
+
+       raw_spin_lock_irq(&p->pi_lock);
+       if (p->state == match_state || p->saved_state == match_state)
+               match = true;
+       raw_spin_unlock_irq(&p->pi_lock);
+
+       return match;
+}
+
 /*
  * wait_task_inactive - wait for a thread to unschedule.
  *
@@ -1431,7 +1593,7 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state)
                 * is actually now running somewhere else!
                 */
                while (task_running(rq, p)) {
-                       if (match_state && unlikely(p->state != match_state))
+                       if (match_state && !check_task_state(p, match_state))
                                return 0;
                        cpu_relax();
                }
@@ -1446,7 +1608,8 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state)
                running = task_running(rq, p);
                queued = task_on_rq_queued(p);
                ncsw = 0;
-               if (!match_state || p->state == match_state)
+               if (!match_state || p->state == match_state ||
+                   p->saved_state == match_state)
                        ncsw = p->nvcsw | LONG_MIN; /* sets MSB */
                task_rq_unlock(rq, p, &rf);
 
@@ -1701,10 +1864,6 @@ static inline void ttwu_activate(struct rq *rq, struct task_struct *p, int en_fl
 {
        activate_task(rq, p, en_flags);
        p->on_rq = TASK_ON_RQ_QUEUED;
-
-       /* if a worker is waking up, notify workqueue */
-       if (p->flags & PF_WQ_WORKER)
-               wq_worker_waking_up(p, cpu_of(rq));
 }
 
 /*
@@ -2043,8 +2202,27 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
         */
        smp_mb__before_spinlock();
        raw_spin_lock_irqsave(&p->pi_lock, flags);
-       if (!(p->state & state))
+       if (!(p->state & state)) {
+               /*
+                * The task might be running due to a spinlock sleeper
+                * wakeup. Check the saved state and set it to running
+                * if the wakeup condition is true.
+                */
+               if (!(wake_flags & WF_LOCK_SLEEPER)) {
+                       if (p->saved_state & state) {
+                               p->saved_state = TASK_RUNNING;
+                               success = 1;
+                       }
+               }
                goto out;
+       }
+
+       /*
+        * If this is a regular wakeup, then we can unconditionally
+        * clear the saved state of a "lock sleeper".
+        */
+       if (!(wake_flags & WF_LOCK_SLEEPER))
+               p->saved_state = TASK_RUNNING;
 
        trace_sched_waking(p);
 
@@ -2137,58 +2315,6 @@ out:
 }
 
 /**
- * try_to_wake_up_local - try to wake up a local task with rq lock held
- * @p: the thread to be awakened
- * @cookie: context's cookie for pinning
- *
- * Put @p on the run-queue if it's not already there. The caller must
- * ensure that this_rq() is locked, @p is bound to this_rq() and not
- * the current task.
- */
-static void try_to_wake_up_local(struct task_struct *p, struct pin_cookie cookie)
-{
-       struct rq *rq = task_rq(p);
-
-       if (WARN_ON_ONCE(rq != this_rq()) ||
-           WARN_ON_ONCE(p == current))
-               return;
-
-       lockdep_assert_held(&rq->lock);
-
-       if (!raw_spin_trylock(&p->pi_lock)) {
-               /*
-                * This is OK, because current is on_cpu, which avoids it being
-                * picked for load-balance and preemption/IRQs are still
-                * disabled avoiding further scheduler activity on it and we've
-                * not yet picked a replacement task.
-                */
-               lockdep_unpin_lock(&rq->lock, cookie);
-               raw_spin_unlock(&rq->lock);
-               raw_spin_lock(&p->pi_lock);
-               raw_spin_lock(&rq->lock);
-               lockdep_repin_lock(&rq->lock, cookie);
-       }
-
-       if (!(p->state & TASK_NORMAL))
-               goto out;
-
-       trace_sched_waking(p);
-
-       if (!task_on_rq_queued(p)) {
-               u64 wallclock = walt_ktime_clock();
-
-               walt_update_task_ravg(rq->curr, rq, TASK_UPDATE, wallclock, 0);
-               walt_update_task_ravg(p, rq, TASK_WAKE, wallclock, 0);
-               ttwu_activate(rq, p, ENQUEUE_WAKEUP);
-       }
-
-       ttwu_do_wakeup(rq, p, 0, cookie);
-       ttwu_stat(p, smp_processor_id(), 0);
-out:
-       raw_spin_unlock(&p->pi_lock);
-}
-
-/**
  * wake_up_process - Wake up a specific process
  * @p: The process to be woken up.
  *
@@ -2206,6 +2332,18 @@ int wake_up_process(struct task_struct *p)
 }
 EXPORT_SYMBOL(wake_up_process);
 
+/**
+ * wake_up_lock_sleeper - Wake up a specific process blocked on a "sleeping lock"
+ * @p: The process to be woken up.
+ *
+ * Same as wake_up_process() above, but wake_flags=WF_LOCK_SLEEPER to indicate
+ * the nature of the wakeup.
+ */
+int wake_up_lock_sleeper(struct task_struct *p)
+{
+       return try_to_wake_up(p, TASK_UNINTERRUPTIBLE, WF_LOCK_SLEEPER);
+}
+
 int wake_up_state(struct task_struct *p, unsigned int state)
 {
        return try_to_wake_up(p, state, 0);
@@ -2488,6 +2626,9 @@ int sched_fork(unsigned long clone_flags, struct task_struct *p)
        p->on_cpu = 0;
 #endif
        init_task_preempt_count(p);
+#ifdef CONFIG_HAVE_PREEMPT_LAZY
+       task_thread_info(p)->preempt_lazy_count = 0;
+#endif
 #ifdef CONFIG_SMP
        plist_node_init(&p->pushable_tasks, MAX_PRIO);
        RB_CLEAR_NODE(&p->pushable_dl_tasks);
@@ -2822,21 +2963,16 @@ static struct rq *finish_task_switch(struct task_struct *prev)
        finish_arch_post_lock_switch();
 
        fire_sched_in_preempt_notifiers(current);
+       /*
+        * We use mmdrop_delayed() here so we don't have to do the
+        * full __mmdrop() when we are the last user.
+        */
        if (mm)
-               mmdrop(mm);
+               mmdrop_delayed(mm);
        if (unlikely(prev_state == TASK_DEAD)) {
                if (prev->sched_class->task_dead)
                        prev->sched_class->task_dead(prev);
 
-               /*
-                * Remove function-return probe instances associated with this
-                * task and put them back on the free list.
-                */
-               kprobe_flush_task(prev);
-
-               /* Task is done with its stack. */
-               put_task_stack(prev);
-
                put_task_struct(prev);
        }
 
@@ -3340,6 +3476,114 @@ static inline void schedule_debug(struct task_struct *prev)
        schedstat_inc(this_rq()->sched_count);
 }
 
+#if defined(CONFIG_PREEMPT_RT_FULL) && defined(CONFIG_SMP)
+
+void migrate_disable(void)
+{
+       struct task_struct *p = current;
+
+       if (in_atomic() || irqs_disabled()) {
+#ifdef CONFIG_SCHED_DEBUG
+               p->migrate_disable_atomic++;
+#endif
+               return;
+       }
+
+#ifdef CONFIG_SCHED_DEBUG
+       if (unlikely(p->migrate_disable_atomic)) {
+               tracing_off();
+               WARN_ON_ONCE(1);
+       }
+#endif
+
+       if (p->migrate_disable) {
+               p->migrate_disable++;
+               return;
+       }
+
+       preempt_disable();
+       preempt_lazy_disable();
+       pin_current_cpu();
+       p->migrate_disable = 1;
+       preempt_enable();
+}
+EXPORT_SYMBOL(migrate_disable);
+
+void migrate_enable(void)
+{
+       struct task_struct *p = current;
+
+       if (in_atomic() || irqs_disabled()) {
+#ifdef CONFIG_SCHED_DEBUG
+               p->migrate_disable_atomic--;
+#endif
+               return;
+       }
+
+#ifdef CONFIG_SCHED_DEBUG
+       if (unlikely(p->migrate_disable_atomic)) {
+               tracing_off();
+               WARN_ON_ONCE(1);
+       }
+#endif
+       WARN_ON_ONCE(p->migrate_disable <= 0);
+
+       if (p->migrate_disable > 1) {
+               p->migrate_disable--;
+               return;
+       }
+
+       preempt_disable();
+       /*
+        * Clearing migrate_disable causes tsk_cpus_allowed to
+        * show the tasks original cpu affinity.
+        */
+       p->migrate_disable = 0;
+
+       if (p->migrate_disable_update) {
+               struct rq *rq;
+               struct rq_flags rf;
+
+               rq = task_rq_lock(p, &rf);
+               update_rq_clock(rq);
+
+               __do_set_cpus_allowed_tail(p, &p->cpus_allowed);
+               task_rq_unlock(rq, p, &rf);
+
+               p->migrate_disable_update = 0;
+
+               WARN_ON(smp_processor_id() != task_cpu(p));
+               if (!cpumask_test_cpu(task_cpu(p), &p->cpus_allowed)) {
+                       const struct cpumask *cpu_valid_mask = cpu_active_mask;
+                       struct migration_arg arg;
+                       unsigned int dest_cpu;
+
+                       if (p->flags & PF_KTHREAD) {
+                               /*
+                                * Kernel threads are allowed on online && !active CPUs
+                                */
+                               cpu_valid_mask = cpu_online_mask;
+                       }
+                       dest_cpu = cpumask_any_and(cpu_valid_mask, &p->cpus_allowed);
+                       arg.task = p;
+                       arg.dest_cpu = dest_cpu;
+
+                       unpin_current_cpu();
+                       preempt_lazy_enable();
+                       preempt_enable();
+                       stop_one_cpu(task_cpu(p), migration_cpu_stop, &arg);
+                       tlb_migrate_finish(p->mm);
+                       return;
+               }
+       }
+
+       unpin_current_cpu();
+       preempt_enable();
+       preempt_lazy_enable();
+}
+EXPORT_SYMBOL(migrate_enable);
+#endif
+
 /*
  * Pick up the highest-prio task:
  */
@@ -3457,19 +3701,6 @@ static void __sched notrace __schedule(bool preempt)
                } else {
                        deactivate_task(rq, prev, DEQUEUE_SLEEP);
                        prev->on_rq = 0;
-
-                       /*
-                        * If a worker went to sleep, notify and ask workqueue
-                        * whether it wants to wake up a task to maintain
-                        * concurrency.
-                        */
-                       if (prev->flags & PF_WQ_WORKER) {
-                               struct task_struct *to_wakeup;
-
-                               to_wakeup = wq_worker_sleeping(prev);
-                               if (to_wakeup)
-                                       try_to_wake_up_local(to_wakeup, cookie);
-                       }
                }
                switch_count = &prev->nvcsw;
        }
@@ -3482,6 +3713,7 @@ static void __sched notrace __schedule(bool preempt)
        walt_update_task_ravg(prev, rq, PUT_PREV_TASK, wallclock, 0);
        walt_update_task_ravg(next, rq, PICK_NEXT_TASK, wallclock, 0);
        clear_tsk_need_resched(prev);
+       clear_tsk_need_resched_lazy(prev);
        clear_preempt_need_resched();
        rq->clock_skip_update = 0;
 
@@ -3533,9 +3765,20 @@ void __noreturn do_task_dead(void)
 
 static inline void sched_submit_work(struct task_struct *tsk)
 {
-       if (!tsk->state || tsk_is_pi_blocked(tsk))
+       if (!tsk->state)
                return;
        /*
+        * If a worker went to sleep, notify and ask workqueue whether
+        * it wants to wake up a task to maintain concurrency.
+        */
+       if (tsk->flags & PF_WQ_WORKER)
+               wq_worker_sleeping(tsk);
+
+
+       if (tsk_is_pi_blocked(tsk))
+               return;
+
+       /*
         * If we are going to sleep and we have plugged IO queued,
         * make sure to submit it to avoid deadlocks.
         */
@@ -3543,6 +3786,12 @@ static inline void sched_submit_work(struct task_struct *tsk)
                blk_schedule_flush_plug(tsk);
 }
 
+static void sched_update_worker(struct task_struct *tsk)
+{
+       if (tsk->flags & PF_WQ_WORKER)
+               wq_worker_running(tsk);
+}
+
 asmlinkage __visible void __sched schedule(void)
 {
        struct task_struct *tsk = current;
@@ -3553,6 +3802,7 @@ asmlinkage __visible void __sched schedule(void)
                __schedule(false);
                sched_preempt_enable_no_resched();
        } while (need_resched());
+       sched_update_worker(tsk);
 }
 EXPORT_SYMBOL(schedule);
 
@@ -3616,6 +3866,30 @@ static void __sched notrace preempt_schedule_common(void)
        } while (need_resched());
 }
 
+#ifdef CONFIG_PREEMPT_LAZY
+/*
+ * If TIF_NEED_RESCHED is then we allow to be scheduled away since this is
+ * set by a RT task. Oterwise we try to avoid beeing scheduled out as long as
+ * preempt_lazy_count counter >0.
+ */
+static __always_inline int preemptible_lazy(void)
+{
+       if (test_thread_flag(TIF_NEED_RESCHED))
+               return 1;
+       if (current_thread_info()->preempt_lazy_count)
+               return 0;
+       return 1;
+}
+
+#else
+
+static inline int preemptible_lazy(void)
+{
+       return 1;
+}
+
+#endif
+
 #ifdef CONFIG_PREEMPT
 /*
  * this is the entry point to schedule() from in-kernel preemption
@@ -3630,7 +3904,8 @@ asmlinkage __visible void __sched notrace preempt_schedule(void)
         */
        if (likely(!preemptible()))
                return;
-
+       if (!preemptible_lazy())
+               return;
        preempt_schedule_common();
 }
 NOKPROBE_SYMBOL(preempt_schedule);
@@ -3657,6 +3932,9 @@ asmlinkage __visible void __sched notrace preempt_schedule_notrace(void)
        if (likely(!preemptible()))
                return;
 
+       if (!preemptible_lazy())
+               return;
+
        do {
                /*
                 * Because the function tracer can trace preempt_count_sub()
@@ -3679,7 +3957,16 @@ asmlinkage __visible void __sched notrace preempt_schedule_notrace(void)
                 * an infinite recursion.
                 */
                prev_ctx = exception_enter();
+               /*
+                * The add/subtract must not be traced by the function
+                * tracer. But we still want to account for the
+                * preempt off latency tracer. Since the _notrace versions
+                * of add/subtract skip the accounting for latency tracer
+                * we must force it manually.
+                */
+               start_critical_timings();
                __schedule(true);
+               stop_critical_timings();
                exception_exit(prev_ctx);
 
                preempt_latency_stop(1);
@@ -3725,10 +4012,25 @@ EXPORT_SYMBOL(default_wake_function);
 
 #ifdef CONFIG_RT_MUTEXES
 
+static inline int __rt_effective_prio(struct task_struct *pi_task, int prio)
+{
+       if (pi_task)
+               prio = min(prio, pi_task->prio);
+
+       return prio;
+}
+
+static inline int rt_effective_prio(struct task_struct *p, int prio)
+{
+       struct task_struct *pi_task = rt_mutex_get_top_task(p);
+
+       return __rt_effective_prio(pi_task, prio);
+}
+
 /*
  * rt_mutex_setprio - set the current priority of a task
- * @p: task
- * @prio: prio value (kernel-internal form)
+ * @p: task to boost
+ * @pi_task: donor task
  *
  * This function changes the 'effective' priority of a task. It does
  * not touch ->normal_prio like __setscheduler().
@@ -3736,17 +4038,41 @@ EXPORT_SYMBOL(default_wake_function);
  * Used by the rt_mutex code to implement priority inheritance
  * logic. Call site only calls if the priority of the task changed.
  */
-void rt_mutex_setprio(struct task_struct *p, int prio)
+void rt_mutex_setprio(struct task_struct *p, struct task_struct *pi_task)
 {
-       int oldprio, queued, running, queue_flag = DEQUEUE_SAVE | DEQUEUE_MOVE;
+       int prio, oldprio, queued, running, queue_flag = DEQUEUE_SAVE | DEQUEUE_MOVE;
        const struct sched_class *prev_class;
        struct rq_flags rf;
        struct rq *rq;
 
-       BUG_ON(prio > MAX_PRIO);
+       /* XXX used to be waiter->prio, not waiter->task->prio */
+       prio = __rt_effective_prio(pi_task, p->normal_prio);
+
+       /*
+        * If nothing changed; bail early.
+        */
+       if (p->pi_top_task == pi_task && prio == p->prio && !dl_prio(prio))
+               return;
 
        rq = __task_rq_lock(p, &rf);
        update_rq_clock(rq);
+       /*
+        * Set under pi_lock && rq->lock, such that the value can be used under
+        * either lock.
+        *
+        * Note that there is loads of tricky to make this pointer cache work
+        * right. rt_mutex_slowunlock()+rt_mutex_postunlock() work together to
+        * ensure a task is de-boosted (pi_task is set to NULL) before the
+        * task is allowed to run again (and can exit). This ensures the pointer
+        * points to a blocked task -- which guaratees the task is present.
+        */
+       p->pi_top_task = pi_task;
+
+       /*
+        * For FIFO/RR we only need to set prio, if that matches we're done.
+        */
+       if (prio == p->prio && !dl_prio(prio))
+               goto out_unlock;
 
        /*
         * Idle task boosting is a nono in general. There is one
@@ -3766,7 +4092,7 @@ void rt_mutex_setprio(struct task_struct *p, int prio)
                goto out_unlock;
        }
 
-       trace_sched_pi_setprio(p, prio);
+       trace_sched_pi_setprio(p, pi_task);
        oldprio = p->prio;
 
        if (oldprio == prio)
@@ -3790,7 +4116,6 @@ void rt_mutex_setprio(struct task_struct *p, int prio)
         *          running task
         */
        if (dl_prio(prio)) {
-               struct task_struct *pi_task = rt_mutex_get_top_task(p);
                if (!dl_prio(p->normal_prio) ||
                    (pi_task && dl_prio(pi_task->prio) &&
                     dl_entity_preempt(&pi_task->dl, &p->dl))) {
@@ -3828,6 +4153,11 @@ out_unlock:
        balance_callback(rq);
        preempt_enable();
 }
+#else
+static inline int rt_effective_prio(struct task_struct *p, int prio)
+{
+       return prio;
+}
 #endif
 
 void set_user_nice(struct task_struct *p, long nice)
@@ -4075,10 +4405,9 @@ static void __setscheduler(struct rq *rq, struct task_struct *p,
         * Keep a potential priority boosting if called from
         * sched_setscheduler().
         */
+       p->prio = normal_prio(p);
        if (keep_boost)
-               p->prio = rt_mutex_get_effective_prio(p, normal_prio(p));
-       else
-               p->prio = normal_prio(p);
+               p->prio = rt_effective_prio(p, p->prio);
 
        if (dl_prio(p->prio))
                p->sched_class = &dl_sched_class;
@@ -4366,7 +4695,7 @@ change:
                 * the runqueue. This will be done when the task deboost
                 * itself.
                 */
-               new_effective_prio = rt_mutex_get_effective_prio(p, newprio);
+               new_effective_prio = rt_effective_prio(p, newprio);
                if (new_effective_prio == oldprio)
                        queue_flags &= ~DEQUEUE_MOVE;
        }
@@ -5041,6 +5370,7 @@ int __cond_resched_lock(spinlock_t *lock)
 }
 EXPORT_SYMBOL(__cond_resched_lock);
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 int __sched __cond_resched_softirq(void)
 {
        BUG_ON(!in_softirq());
@@ -5054,6 +5384,7 @@ int __sched __cond_resched_softirq(void)
        return 0;
 }
 EXPORT_SYMBOL(__cond_resched_softirq);
+#endif
 
 /**
  * yield - yield the current processor to other threads.
@@ -5417,7 +5748,9 @@ void init_idle(struct task_struct *idle, int cpu)
 
        /* Set the preempt count _outside_ the spinlocks! */
        init_idle_preempt_count(idle, cpu);
-
+#ifdef CONFIG_HAVE_PREEMPT_LAZY
+       task_thread_info(idle)->preempt_lazy_count = 0;
+#endif
        /*
         * The idle tasks have their own, simple scheduling class:
         */
@@ -5560,6 +5893,8 @@ void sched_setnuma(struct task_struct *p, int nid)
 #endif /* CONFIG_NUMA_BALANCING */
 
 #ifdef CONFIG_HOTPLUG_CPU
+static DEFINE_PER_CPU(struct mm_struct *, idle_last_mm);
+
 /*
  * Ensures that the idle task is using init_mm right before its cpu goes
  * offline.
@@ -5574,7 +5909,12 @@ void idle_task_exit(void)
                switch_mm(mm, &init_mm, current);
                finish_arch_post_lock_switch();
        }
-       mmdrop(mm);
+       /*
+        * Defer the cleanup to an alive cpu. On RT we can neither
+        * call mmdrop() nor mmdrop_delayed() from here.
+        */
+       per_cpu(idle_last_mm, smp_processor_id()) = mm;
+
 }
 
 /*
@@ -6003,6 +6343,7 @@ static int init_rootdomain(struct root_domain *rd)
        rd->rto_cpu = -1;
        raw_spin_lock_init(&rd->rto_lock);
        init_irq_work(&rd->rto_push_work, rto_push_irq_work_func);
+       rd->rto_push_work.flags |= IRQ_WORK_HARD_IRQ;
 #endif
 
        init_dl_bw(&rd->dl_bw);
@@ -7669,6 +8010,10 @@ int sched_cpu_dying(unsigned int cpu)
        update_max_interval();
        nohz_balance_exit_idle(cpu);
        hrtick_clear(rq);
+       if (per_cpu(idle_last_mm, cpu)) {
+               mmdrop_delayed(per_cpu(idle_last_mm, cpu));
+               per_cpu(idle_last_mm, cpu) = NULL;
+       }
        return 0;
 }
 #endif
@@ -7937,7 +8282,7 @@ void __init sched_init(void)
 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
 static inline int preempt_count_equals(int preempt_offset)
 {
-       int nested = preempt_count() + rcu_preempt_depth();
+       int nested = preempt_count() + sched_rcu_preempt_depth();
 
        return (nested == preempt_offset);
 }
index d464490..cff53a3 100644 (file)
@@ -774,6 +774,7 @@ void init_dl_task_timer(struct sched_dl_entity *dl_se)
 
        hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
        timer->function = dl_task_timer;
+       timer->irqsafe = 1;
 }
 
 /*
index e7f7034..237fc0a 100644 (file)
@@ -633,6 +633,9 @@ void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq)
        P(rt_throttled);
        PN(rt_time);
        PN(rt_runtime);
+#ifdef CONFIG_SMP
+       P(rt_nr_migratory);
+#endif
 
 #undef PN
 #undef P
@@ -1054,6 +1057,10 @@ void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
 #endif
        P(policy);
        P(prio);
+#ifdef CONFIG_PREEMPT_RT_FULL
+       P(migrate_disable);
+#endif
+       P(nr_cpus_allowed);
 #undef PN_SCHEDSTAT
 #undef PN
 #undef __PN
index 43df721..b2cf476 100644 (file)
@@ -3797,7 +3797,7 @@ check_preempt_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr)
        ideal_runtime = sched_slice(cfs_rq, curr);
        delta_exec = curr->sum_exec_runtime - curr->prev_sum_exec_runtime;
        if (delta_exec > ideal_runtime) {
-               resched_curr(rq_of(cfs_rq));
+               resched_curr_lazy(rq_of(cfs_rq));
                /*
                 * The current task ran long enough, ensure it doesn't get
                 * re-elected due to buddy favours.
@@ -3821,7 +3821,7 @@ check_preempt_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr)
                return;
 
        if (delta > ideal_runtime)
-               resched_curr(rq_of(cfs_rq));
+               resched_curr_lazy(rq_of(cfs_rq));
 }
 
 static void
@@ -3963,7 +3963,7 @@ entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr, int queued)
         * validating it and just reschedule.
         */
        if (queued) {
-               resched_curr(rq_of(cfs_rq));
+               resched_curr_lazy(rq_of(cfs_rq));
                return;
        }
        /*
@@ -4147,7 +4147,7 @@ static void __account_cfs_rq_runtime(struct cfs_rq *cfs_rq, u64 delta_exec)
         * hierarchy can be throttled
         */
        if (!assign_cfs_rq_runtime(cfs_rq) && likely(cfs_rq->curr))
-               resched_curr(rq_of(cfs_rq));
+               resched_curr_lazy(rq_of(cfs_rq));
 }
 
 static __always_inline
@@ -4827,7 +4827,7 @@ static void hrtick_start_fair(struct rq *rq, struct task_struct *p)
 
                if (delta < 0) {
                        if (rq->curr == p)
-                               resched_curr(rq);
+                               resched_curr_lazy(rq);
                        return;
                }
                hrtick_start(rq, delta);
@@ -7521,7 +7521,7 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_
        return;
 
 preempt:
-       resched_curr(rq);
+       resched_curr_lazy(rq);
        /*
         * Only set the backward buddy when the current task is still
         * on the rq. This can happen when a wakeup gets interleaved
@@ -10555,7 +10555,7 @@ static void task_fork_fair(struct task_struct *p)
                 * 'current' within the tree based on its new key value.
                 */
                swap(curr->vruntime, se->vruntime);
-               resched_curr(rq);
+               resched_curr_lazy(rq);
        }
 
        se->vruntime -= cfs_rq->min_vruntime;
@@ -10579,7 +10579,7 @@ prio_changed_fair(struct rq *rq, struct task_struct *p, int oldprio)
         */
        if (rq->curr == p) {
                if (p->prio > oldprio)
-                       resched_curr(rq);
+                       resched_curr_lazy(rq);
        } else
                check_preempt_curr(rq, p, 0);
 }
index c7f1bdd..de3f5b0 100644 (file)
@@ -45,11 +45,19 @@ SCHED_FEAT(LB_BIAS, true)
  */
 SCHED_FEAT(NONTASK_CAPACITY, true)
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+SCHED_FEAT(TTWU_QUEUE, false)
+# ifdef CONFIG_PREEMPT_LAZY
+SCHED_FEAT(PREEMPT_LAZY, true)
+# endif
+#else
+
 /*
  * Queue remote wakeups on the target CPU and process them
  * using the scheduler IPI. Reduces rq->lock contention/bounces.
  */
 SCHED_FEAT(TTWU_QUEUE, true)
+#endif
 
 /*
  * When doing wakeups, attempt to limit superfluous scans of the LLC domain.
index e73b9d7..503172c 100644 (file)
@@ -50,6 +50,7 @@ void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime)
 
        hrtimer_init(&rt_b->rt_period_timer,
                        CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+       rt_b->rt_period_timer.irqsafe = 1;
        rt_b->rt_period_timer.function = sched_rt_period_timer;
 }
 
index da38f3f..9181a48 100644 (file)
@@ -1227,6 +1227,7 @@ static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
 #define WF_SYNC                0x01            /* waker goes to sleep after wakeup */
 #define WF_FORK                0x02            /* child wakeup after fork */
 #define WF_MIGRATED    0x4             /* internal use, task got migrated */
+#define WF_LOCK_SLEEPER        0x08            /* wakeup spinlock "sleeper" */
 
 /*
  * To aid in avoiding the subversion of "niceness" due to uneven distribution
@@ -1432,6 +1433,15 @@ extern void init_sched_fair_class(void);
 extern void resched_curr(struct rq *rq);
 extern void resched_cpu(int cpu);
 
+#ifdef CONFIG_PREEMPT_LAZY
+extern void resched_curr_lazy(struct rq *rq);
+#else
+static inline void resched_curr_lazy(struct rq *rq)
+{
+       resched_curr(rq);
+}
+#endif
+
 extern struct rt_bandwidth def_rt_bandwidth;
 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
 
index 9c2da06..d29069d 100644 (file)
@@ -1,5 +1,6 @@
 #include <linux/sched.h>
 #include <linux/swait.h>
+#include <linux/suspend.h>
 
 void __init_swait_queue_head(struct swait_queue_head *q, const char *name,
                             struct lock_class_key *key)
@@ -29,6 +30,25 @@ void swake_up_locked(struct swait_queue_head *q)
 }
 EXPORT_SYMBOL(swake_up_locked);
 
+void swake_up_all_locked(struct swait_queue_head *q)
+{
+       struct swait_queue *curr;
+       int wakes = 0;
+
+       while (!list_empty(&q->task_list)) {
+
+               curr = list_first_entry(&q->task_list, typeof(*curr),
+                                       task_list);
+               wake_up_process(curr->task);
+               list_del_init(&curr->task_list);
+               wakes++;
+       }
+       if (pm_in_action)
+               return;
+       WARN(wakes > 2, "complete_all() with %d waiters\n", wakes);
+}
+EXPORT_SYMBOL(swake_up_all_locked);
+
 void swake_up(struct swait_queue_head *q)
 {
        unsigned long flags;
@@ -48,6 +68,7 @@ void swake_up_all(struct swait_queue_head *q)
        struct swait_queue *curr;
        LIST_HEAD(tmp);
 
+       WARN_ON(irqs_disabled());
        raw_spin_lock_irq(&q->lock);
        list_splice_init(&q->task_list, &tmp);
        while (!list_empty(&tmp)) {
diff --git a/kernel/sched/swork.c b/kernel/sched/swork.c
new file mode 100644 (file)
index 0000000..1950f40
--- /dev/null
@@ -0,0 +1,173 @@
+/*
+ * Copyright (C) 2014 BMW Car IT GmbH, Daniel Wagner daniel.wagner@bmw-carit.de
+ *
+ * Provides a framework for enqueuing callbacks from irq context
+ * PREEMPT_RT_FULL safe. The callbacks are executed in kthread context.
+ */
+
+#include <linux/swait.h>
+#include <linux/swork.h>
+#include <linux/kthread.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/export.h>
+
+#define SWORK_EVENT_PENDING     (1 << 0)
+
+static DEFINE_MUTEX(worker_mutex);
+static struct sworker *glob_worker;
+
+struct sworker {
+       struct list_head events;
+       struct swait_queue_head wq;
+
+       raw_spinlock_t lock;
+
+       struct task_struct *task;
+       int refs;
+};
+
+static bool swork_readable(struct sworker *worker)
+{
+       bool r;
+
+       if (kthread_should_stop())
+               return true;
+
+       raw_spin_lock_irq(&worker->lock);
+       r = !list_empty(&worker->events);
+       raw_spin_unlock_irq(&worker->lock);
+
+       return r;
+}
+
+static int swork_kthread(void *arg)
+{
+       struct sworker *worker = arg;
+
+       for (;;) {
+               swait_event_interruptible(worker->wq,
+                                       swork_readable(worker));
+               if (kthread_should_stop())
+                       break;
+
+               raw_spin_lock_irq(&worker->lock);
+               while (!list_empty(&worker->events)) {
+                       struct swork_event *sev;
+
+                       sev = list_first_entry(&worker->events,
+                                       struct swork_event, item);
+                       list_del(&sev->item);
+                       raw_spin_unlock_irq(&worker->lock);
+
+                       WARN_ON_ONCE(!test_and_clear_bit(SWORK_EVENT_PENDING,
+                                                        &sev->flags));
+                       sev->func(sev);
+                       raw_spin_lock_irq(&worker->lock);
+               }
+               raw_spin_unlock_irq(&worker->lock);
+       }
+       return 0;
+}
+
+static struct sworker *swork_create(void)
+{
+       struct sworker *worker;
+
+       worker = kzalloc(sizeof(*worker), GFP_KERNEL);
+       if (!worker)
+               return ERR_PTR(-ENOMEM);
+
+       INIT_LIST_HEAD(&worker->events);
+       raw_spin_lock_init(&worker->lock);
+       init_swait_queue_head(&worker->wq);
+
+       worker->task = kthread_run(swork_kthread, worker, "kswork");
+       if (IS_ERR(worker->task)) {
+               kfree(worker);
+               return ERR_PTR(-ENOMEM);
+       }
+
+       return worker;
+}
+
+static void swork_destroy(struct sworker *worker)
+{
+       kthread_stop(worker->task);
+
+       WARN_ON(!list_empty(&worker->events));
+       kfree(worker);
+}
+
+/**
+ * swork_queue - queue swork
+ *
+ * Returns %false if @work was already on a queue, %true otherwise.
+ *
+ * The work is queued and processed on a random CPU
+ */
+bool swork_queue(struct swork_event *sev)
+{
+       unsigned long flags;
+
+       if (test_and_set_bit(SWORK_EVENT_PENDING, &sev->flags))
+               return false;
+
+       raw_spin_lock_irqsave(&glob_worker->lock, flags);
+       list_add_tail(&sev->item, &glob_worker->events);
+       raw_spin_unlock_irqrestore(&glob_worker->lock, flags);
+
+       swake_up(&glob_worker->wq);
+       return true;
+}
+EXPORT_SYMBOL_GPL(swork_queue);
+
+/**
+ * swork_get - get an instance of the sworker
+ *
+ * Returns an negative error code if the initialization if the worker did not
+ * work, %0 otherwise.
+ *
+ */
+int swork_get(void)
+{
+       struct sworker *worker;
+
+       mutex_lock(&worker_mutex);
+       if (!glob_worker) {
+               worker = swork_create();
+               if (IS_ERR(worker)) {
+                       mutex_unlock(&worker_mutex);
+                       return -ENOMEM;
+               }
+
+               glob_worker = worker;
+       }
+
+       glob_worker->refs++;
+       mutex_unlock(&worker_mutex);
+
+       return 0;
+}
+EXPORT_SYMBOL_GPL(swork_get);
+
+/**
+ * swork_put - puts an instance of the sworker
+ *
+ * Will destroy the sworker thread. This function must not be called until all
+ * queued events have been completed.
+ */
+void swork_put(void)
+{
+       mutex_lock(&worker_mutex);
+
+       glob_worker->refs--;
+       if (glob_worker->refs > 0)
+               goto out;
+
+       swork_destroy(glob_worker);
+       glob_worker = NULL;
+out:
+       mutex_unlock(&worker_mutex);
+}
+EXPORT_SYMBOL_GPL(swork_put);
index bedca16..aca4b4c 100644 (file)
@@ -14,6 +14,7 @@
 #include <linux/export.h>
 #include <linux/init.h>
 #include <linux/sched.h>
+#include <linux/sched/rt.h>
 #include <linux/fs.h>
 #include <linux/tty.h>
 #include <linux/binfmts.h>
@@ -363,13 +364,30 @@ static bool task_participate_group_stop(struct task_struct *task)
        return false;
 }
 
+static inline struct sigqueue *get_task_cache(struct task_struct *t)
+{
+       struct sigqueue *q = t->sigqueue_cache;
+
+       if (cmpxchg(&t->sigqueue_cache, q, NULL) != q)
+               return NULL;
+       return q;
+}
+
+static inline int put_task_cache(struct task_struct *t, struct sigqueue *q)
+{
+       if (cmpxchg(&t->sigqueue_cache, NULL, q) == NULL)
+               return 0;
+       return 1;
+}
+
 /*
  * allocate a new signal queue record
  * - this may be called without locks if and only if t == current, otherwise an
  *   appropriate lock must be held to stop the target task from exiting
  */
 static struct sigqueue *
-__sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimit)
+__sigqueue_do_alloc(int sig, struct task_struct *t, gfp_t flags,
+                   int override_rlimit, int fromslab)
 {
        struct sigqueue *q = NULL;
        struct user_struct *user;
@@ -390,8 +408,13 @@ __sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimi
                get_uid(user);
        rcu_read_unlock();
 
-       if (override_rlimit || likely(sigpending <= task_rlimit(t, RLIMIT_SIGPENDING))) {
-               q = kmem_cache_alloc(sigqueue_cachep, flags);
+       if (override_rlimit ||
+           atomic_read(&user->sigpending) <=
+                       task_rlimit(t, RLIMIT_SIGPENDING)) {
+               if (!fromslab)
+                       q = get_task_cache(t);
+               if (!q)
+                       q = kmem_cache_alloc(sigqueue_cachep, flags);
        } else {
                print_dropped_signal(sig);
        }
@@ -408,6 +431,13 @@ __sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimi
        return q;
 }
 
+static struct sigqueue *
+__sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags,
+                int override_rlimit)
+{
+       return __sigqueue_do_alloc(sig, t, flags, override_rlimit, 0);
+}
+
 static void __sigqueue_free(struct sigqueue *q)
 {
        if (q->flags & SIGQUEUE_PREALLOC)
@@ -417,6 +447,21 @@ static void __sigqueue_free(struct sigqueue *q)
        kmem_cache_free(sigqueue_cachep, q);
 }
 
+static void sigqueue_free_current(struct sigqueue *q)
+{
+       struct user_struct *up;
+
+       if (q->flags & SIGQUEUE_PREALLOC)
+               return;
+
+       up = q->user;
+       if (rt_prio(current->normal_prio) && !put_task_cache(current, q)) {
+               atomic_dec(&up->sigpending);
+               free_uid(up);
+       } else
+                 __sigqueue_free(q);
+}
+
 void flush_sigqueue(struct sigpending *queue)
 {
        struct sigqueue *q;
@@ -430,6 +475,21 @@ void flush_sigqueue(struct sigpending *queue)
 }
 
 /*
+ * Called from __exit_signal. Flush tsk->pending and
+ * tsk->sigqueue_cache
+ */
+void flush_task_sigqueue(struct task_struct *tsk)
+{
+       struct sigqueue *q;
+
+       flush_sigqueue(&tsk->pending);
+
+       q = get_task_cache(tsk);
+       if (q)
+               kmem_cache_free(sigqueue_cachep, q);
+}
+
+/*
  * Flush all pending signals for this kthread.
  */
 void flush_signals(struct task_struct *t)
@@ -548,7 +608,7 @@ still_pending:
                        (info->si_code == SI_TIMER) &&
                        (info->si_sys_private);
 
-               __sigqueue_free(first);
+               sigqueue_free_current(first);
        } else {
                /*
                 * Ok, it wasn't in the queue.  This must be
@@ -584,6 +644,8 @@ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
        bool resched_timer = false;
        int signr;
 
+       WARN_ON_ONCE(tsk != current);
+
        /* We only dequeue private signals from ourselves, we don't let
         * signalfd steal them
         */
@@ -1222,8 +1284,8 @@ int do_send_sig_info(int sig, struct siginfo *info, struct task_struct *p,
  * We don't want to have recursive SIGSEGV's etc, for example,
  * that is why we also clear SIGNAL_UNKILLABLE.
  */
-int
-force_sig_info(int sig, struct siginfo *info, struct task_struct *t)
+static int
+do_force_sig_info(int sig, struct siginfo *info, struct task_struct *t)
 {
        unsigned long int flags;
        int ret, blocked, ignored;
@@ -1248,6 +1310,39 @@ force_sig_info(int sig, struct siginfo *info, struct task_struct *t)
        return ret;
 }
 
+int force_sig_info(int sig, struct siginfo *info, struct task_struct *t)
+{
+/*
+ * On some archs, PREEMPT_RT has to delay sending a signal from a trap
+ * since it can not enable preemption, and the signal code's spin_locks
+ * turn into mutexes. Instead, it must set TIF_NOTIFY_RESUME which will
+ * send the signal on exit of the trap.
+ */
+#ifdef ARCH_RT_DELAYS_SIGNAL_SEND
+       if (in_atomic()) {
+               if (WARN_ON_ONCE(t != current))
+                       return 0;
+               if (WARN_ON_ONCE(t->forced_info.si_signo))
+                       return 0;
+
+               if (is_si_special(info)) {
+                       WARN_ON_ONCE(info != SEND_SIG_PRIV);
+                       t->forced_info.si_signo = sig;
+                       t->forced_info.si_errno = 0;
+                       t->forced_info.si_code = SI_KERNEL;
+                       t->forced_info.si_pid = 0;
+                       t->forced_info.si_uid = 0;
+               } else {
+                       t->forced_info = *info;
+               }
+
+               set_tsk_thread_flag(t, TIF_NOTIFY_RESUME);
+               return 0;
+       }
+#endif
+       return do_force_sig_info(sig, info, t);
+}
+
 /*
  * Nuke all other threads in the group.
  */
@@ -1282,12 +1377,12 @@ struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
                 * Disable interrupts early to avoid deadlocks.
                 * See rcu_read_unlock() comment header for details.
                 */
-               local_irq_save(*flags);
+               local_irq_save_nort(*flags);
                rcu_read_lock();
                sighand = rcu_dereference(tsk->sighand);
                if (unlikely(sighand == NULL)) {
                        rcu_read_unlock();
-                       local_irq_restore(*flags);
+                       local_irq_restore_nort(*flags);
                        break;
                }
                /*
@@ -1308,7 +1403,7 @@ struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
                }
                spin_unlock(&sighand->siglock);
                rcu_read_unlock();
-               local_irq_restore(*flags);
+               local_irq_restore_nort(*flags);
        }
 
        return sighand;
@@ -1555,7 +1650,8 @@ EXPORT_SYMBOL(kill_pid);
  */
 struct sigqueue *sigqueue_alloc(void)
 {
-       struct sigqueue *q = __sigqueue_alloc(-1, current, GFP_KERNEL, 0);
+       /* Preallocated sigqueue objects always from the slabcache ! */
+       struct sigqueue *q = __sigqueue_do_alloc(-1, current, GFP_KERNEL, 0, 1);
 
        if (q)
                q->flags |= SIGQUEUE_PREALLOC;
@@ -1916,15 +2012,7 @@ static void ptrace_stop(int exit_code, int why, int clear_code, siginfo_t *info)
                if (gstop_done && ptrace_reparented(current))
                        do_notify_parent_cldstop(current, false, why);
 
-               /*
-                * Don't want to allow preemption here, because
-                * sys_ptrace() needs this task to be inactive.
-                *
-                * XXX: implement read_unlock_no_resched().
-                */
-               preempt_disable();
                read_unlock(&tasklist_lock);
-               preempt_enable_no_resched();
                freezable_schedule();
        } else {
                /*
@@ -2403,7 +2491,7 @@ relock:
 }
 
 /**
- * signal_delivered - 
+ * signal_delivered -
  * @ksig:              kernel signal struct
  * @stepping:          nonzero if debugger single-step or block-step in use
  *
@@ -3347,7 +3435,7 @@ int __compat_save_altstack(compat_stack_t __user *uss, unsigned long sp)
  */
 SYSCALL_DEFINE1(sigpending, old_sigset_t __user *, set)
 {
-       return sys_rt_sigpending((sigset_t __user *)set, sizeof(old_sigset_t)); 
+       return sys_rt_sigpending((sigset_t __user *)set, sizeof(old_sigset_t));
 }
 
 #endif
@@ -3472,7 +3560,7 @@ COMPAT_SYSCALL_DEFINE4(rt_sigaction, int, sig,
        ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
        if (!ret && oact) {
                sigset_to_compat(&mask, &old_ka.sa.sa_mask);
-               ret = put_user(ptr_to_compat(old_ka.sa.sa_handler), 
+               ret = put_user(ptr_to_compat(old_ka.sa.sa_handler),
                               &oact->sa_handler);
                ret |= copy_to_user(&oact->sa_mask, &mask, sizeof(mask));
                ret |= put_user(old_ka.sa.sa_flags, &oact->sa_flags);
@@ -3650,7 +3738,7 @@ SYSCALL_DEFINE2(rt_sigsuspend, sigset_t __user *, unewset, size_t, sigsetsize)
                return -EFAULT;
        return sigsuspend(&newset);
 }
+
 #ifdef CONFIG_COMPAT
 COMPAT_SYSCALL_DEFINE2(rt_sigsuspend, compat_sigset_t __user *, unewset, compat_size_t, sigsetsize)
 {
index d7557d4..a1db23f 100644 (file)
 #include <linux/freezer.h>
 #include <linux/kthread.h>
 #include <linux/rcupdate.h>
+#include <linux/delay.h>
 #include <linux/ftrace.h>
 #include <linux/smp.h>
 #include <linux/smpboot.h>
 #include <linux/tick.h>
+#include <linux/locallock.h>
 #include <linux/irq.h>
 
 #ifndef CONFIG_AMLOGIC_MODIFY
@@ -60,12 +62,108 @@ EXPORT_SYMBOL(irq_stat);
 static struct softirq_action softirq_vec[NR_SOFTIRQS] __cacheline_aligned_in_smp;
 
 DEFINE_PER_CPU(struct task_struct *, ksoftirqd);
+#ifdef CONFIG_PREEMPT_RT_FULL
+#define TIMER_SOFTIRQS ((1 << TIMER_SOFTIRQ) | (1 << HRTIMER_SOFTIRQ))
+DEFINE_PER_CPU(struct task_struct *, ktimer_softirqd);
+#endif
 
 const char * const softirq_to_name[NR_SOFTIRQS] = {
        "HI", "TIMER", "NET_TX", "NET_RX", "BLOCK", "IRQ_POLL",
        "TASKLET", "SCHED", "HRTIMER", "RCU"
 };
 
+#ifdef CONFIG_NO_HZ_COMMON
+# ifdef CONFIG_PREEMPT_RT_FULL
+
+struct softirq_runner {
+       struct task_struct *runner[NR_SOFTIRQS];
+};
+
+static DEFINE_PER_CPU(struct softirq_runner, softirq_runners);
+
+static inline void softirq_set_runner(unsigned int sirq)
+{
+       struct softirq_runner *sr = this_cpu_ptr(&softirq_runners);
+
+       sr->runner[sirq] = current;
+}
+
+static inline void softirq_clr_runner(unsigned int sirq)
+{
+       struct softirq_runner *sr = this_cpu_ptr(&softirq_runners);
+
+       sr->runner[sirq] = NULL;
+}
+
+/*
+ * On preempt-rt a softirq running context might be blocked on a
+ * lock. There might be no other runnable task on this CPU because the
+ * lock owner runs on some other CPU. So we have to go into idle with
+ * the pending bit set. Therefor we need to check this otherwise we
+ * warn about false positives which confuses users and defeats the
+ * whole purpose of this test.
+ *
+ * This code is called with interrupts disabled.
+ */
+void softirq_check_pending_idle(void)
+{
+       static int rate_limit;
+       struct softirq_runner *sr = this_cpu_ptr(&softirq_runners);
+       u32 warnpending;
+       int i;
+
+       if (rate_limit >= 10)
+               return;
+
+       warnpending = local_softirq_pending() & SOFTIRQ_STOP_IDLE_MASK;
+       for (i = 0; i < NR_SOFTIRQS; i++) {
+               struct task_struct *tsk = sr->runner[i];
+
+               /*
+                * The wakeup code in rtmutex.c wakes up the task
+                * _before_ it sets pi_blocked_on to NULL under
+                * tsk->pi_lock. So we need to check for both: state
+                * and pi_blocked_on.
+                */
+               if (tsk) {
+                       raw_spin_lock(&tsk->pi_lock);
+                       if (tsk->pi_blocked_on || tsk->state == TASK_RUNNING) {
+                               /* Clear all bits pending in that task */
+                               warnpending &= ~(tsk->softirqs_raised);
+                               warnpending &= ~(1 << i);
+                       }
+                       raw_spin_unlock(&tsk->pi_lock);
+               }
+       }
+
+       if (warnpending) {
+               printk(KERN_ERR "NOHZ: local_softirq_pending %02x\n",
+                      warnpending);
+               rate_limit++;
+       }
+}
+# else
+/*
+ * On !PREEMPT_RT we just printk rate limited:
+ */
+void softirq_check_pending_idle(void)
+{
+       static int rate_limit;
+
+       if (rate_limit < 10 &&
+                       (local_softirq_pending() & SOFTIRQ_STOP_IDLE_MASK)) {
+               printk(KERN_ERR "NOHZ: local_softirq_pending %02x\n",
+                      local_softirq_pending());
+               rate_limit++;
+       }
+}
+# endif
+
+#else /* !CONFIG_NO_HZ_COMMON */
+static inline void softirq_set_runner(unsigned int sirq) { }
+static inline void softirq_clr_runner(unsigned int sirq) { }
+#endif
+
 /*
  * we cannot loop indefinitely here to avoid userspace starvation,
  * but we also don't want to introduce a worst case 1/HZ latency
@@ -81,6 +179,49 @@ static void wakeup_softirqd(void)
                wake_up_process(tsk);
 }
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+static void wakeup_timer_softirqd(void)
+{
+       /* Interrupts are disabled: no need to stop preemption */
+       struct task_struct *tsk = __this_cpu_read(ktimer_softirqd);
+
+       if (tsk && tsk->state != TASK_RUNNING)
+               wake_up_process(tsk);
+}
+#endif
+
+static void handle_softirq(unsigned int vec_nr)
+{
+       struct softirq_action *h = softirq_vec + vec_nr;
+       int prev_count;
+#ifdef CONFIG_AMLOGIC_DEBUG_LOCKUP
+       int cpu;
+       unsigned long long tin;
+#endif
+
+       prev_count = preempt_count();
+
+       kstat_incr_softirqs_this_cpu(vec_nr);
+
+       trace_softirq_entry(vec_nr);
+#ifdef CONFIG_AMLOGIC_DEBUG_LOCKUP
+       cpu = smp_processor_id();
+       sirq_in_hook(cpu, &tin, (void *)h->action);
+#endif
+       h->action(h);
+#ifdef CONFIG_AMLOGIC_DEBUG_LOCKUP
+       sirq_out_hook(cpu, tin, (void *)h->action);
+#endif
+       trace_softirq_exit(vec_nr);
+       if (unlikely(prev_count != preempt_count())) {
+               pr_err("huh, entered softirq %u %s %p with preempt_count %08x, exited with %08x?\n",
+                      vec_nr, softirq_to_name[vec_nr], h->action,
+                      prev_count, preempt_count());
+               preempt_count_set(prev_count);
+       }
+}
+
+#ifndef CONFIG_PREEMPT_RT_FULL
 /*
  * If ksoftirqd is scheduled, we do not want to process pending softirqs
  * right now. Let ksoftirqd handle this at its own rate, to get fairness,
@@ -96,6 +237,47 @@ static bool ksoftirqd_running(unsigned long pending)
        return tsk && (tsk->state == TASK_RUNNING);
 }
 
+static inline int ksoftirqd_softirq_pending(void)
+{
+       return local_softirq_pending();
+}
+
+static void handle_pending_softirqs(u32 pending)
+{
+       struct softirq_action *h = softirq_vec;
+       int softirq_bit;
+
+       local_irq_enable();
+
+       h = softirq_vec;
+
+       while ((softirq_bit = ffs(pending))) {
+               unsigned int vec_nr;
+
+               h += softirq_bit - 1;
+               vec_nr = h - softirq_vec;
+               handle_softirq(vec_nr);
+
+               h++;
+               pending >>= softirq_bit;
+       }
+
+       rcu_bh_qs();
+       local_irq_disable();
+}
+
+static void run_ksoftirqd(unsigned int cpu)
+{
+       local_irq_disable();
+       if (ksoftirqd_softirq_pending()) {
+               __do_softirq();
+               local_irq_enable();
+               cond_resched_rcu_qs();
+               return;
+       }
+       local_irq_enable();
+}
+
 /*
  * preempt_count and SOFTIRQ_OFFSET usage:
  * - preempt_count is changed by SOFTIRQ_OFFSET on entering or leaving
@@ -251,14 +433,8 @@ asmlinkage __visible void __softirq_entry __do_softirq(void)
        unsigned long end = jiffies + MAX_SOFTIRQ_TIME;
        unsigned long old_flags = current->flags;
        int max_restart = MAX_SOFTIRQ_RESTART;
-       struct softirq_action *h;
        bool in_hardirq;
        __u32 pending;
-       int softirq_bit;
-#ifdef CONFIG_AMLOGIC_DEBUG_LOCKUP
-       int cpu;
-       unsigned long long tin;
-#endif
 
        /*
         * Mask out PF_MEMALLOC s current task context is borrowed for the
@@ -277,43 +453,7 @@ restart:
        /* Reset the pending bitmask before enabling irqs */
        set_softirq_pending(0);
 
-       local_irq_enable();
-
-       h = softirq_vec;
-
-       while ((softirq_bit = ffs(pending))) {
-               unsigned int vec_nr;
-               int prev_count;
-
-               h += softirq_bit - 1;
-
-               vec_nr = h - softirq_vec;
-               prev_count = preempt_count();
-
-               kstat_incr_softirqs_this_cpu(vec_nr);
-
-               trace_softirq_entry(vec_nr);
-#ifdef CONFIG_AMLOGIC_DEBUG_LOCKUP
-               cpu = smp_processor_id();
-               sirq_in_hook(cpu, &tin, (void *)h->action);
-#endif
-               h->action(h);
-#ifdef CONFIG_AMLOGIC_DEBUG_LOCKUP
-               sirq_out_hook(cpu, tin, (void *)h->action);
-#endif
-               trace_softirq_exit(vec_nr);
-               if (unlikely(prev_count != preempt_count())) {
-                       pr_err("huh, entered softirq %u %s %p with preempt_count %08x, exited with %08x?\n",
-                              vec_nr, softirq_to_name[vec_nr], h->action,
-                              prev_count, preempt_count());
-                       preempt_count_set(prev_count);
-               }
-               h++;
-               pending >>= softirq_bit;
-       }
-
-       rcu_bh_qs();
-       local_irq_disable();
+       handle_pending_softirqs(pending);
 
        pending = local_softirq_pending();
        if (pending) {
@@ -350,6 +490,309 @@ asmlinkage __visible void do_softirq(void)
 }
 
 /*
+ * This function must run with irqs disabled!
+ */
+void raise_softirq_irqoff(unsigned int nr)
+{
+       __raise_softirq_irqoff(nr);
+
+       /*
+        * If we're in an interrupt or softirq, we're done
+        * (this also catches softirq-disabled code). We will
+        * actually run the softirq once we return from
+        * the irq or softirq.
+        *
+        * Otherwise we wake up ksoftirqd to make sure we
+        * schedule the softirq soon.
+        */
+       if (!in_interrupt())
+               wakeup_softirqd();
+}
+
+void __raise_softirq_irqoff(unsigned int nr)
+{
+       trace_softirq_raise(nr);
+       or_softirq_pending(1UL << nr);
+}
+
+static inline void local_bh_disable_nort(void) { local_bh_disable(); }
+static inline void _local_bh_enable_nort(void) { _local_bh_enable(); }
+static void ksoftirqd_set_sched_params(unsigned int cpu) { }
+
+#else /* !PREEMPT_RT_FULL */
+
+/*
+ * On RT we serialize softirq execution with a cpu local lock per softirq
+ */
+static DEFINE_PER_CPU(struct local_irq_lock [NR_SOFTIRQS], local_softirq_locks);
+
+void __init softirq_early_init(void)
+{
+       int i;
+
+       for (i = 0; i < NR_SOFTIRQS; i++)
+               local_irq_lock_init(local_softirq_locks[i]);
+}
+
+static void lock_softirq(int which)
+{
+       local_lock(local_softirq_locks[which]);
+}
+
+static void unlock_softirq(int which)
+{
+       local_unlock(local_softirq_locks[which]);
+}
+
+static void do_single_softirq(int which)
+{
+       unsigned long old_flags = current->flags;
+
+       current->flags &= ~PF_MEMALLOC;
+       vtime_account_irq_enter(current);
+       current->flags |= PF_IN_SOFTIRQ;
+       lockdep_softirq_enter();
+       local_irq_enable();
+       handle_softirq(which);
+       local_irq_disable();
+       lockdep_softirq_exit();
+       current->flags &= ~PF_IN_SOFTIRQ;
+       vtime_account_irq_enter(current);
+       tsk_restore_flags(current, old_flags, PF_MEMALLOC);
+}
+
+/*
+ * Called with interrupts disabled. Process softirqs which were raised
+ * in current context (or on behalf of ksoftirqd).
+ */
+static void do_current_softirqs(void)
+{
+       while (current->softirqs_raised) {
+               int i = __ffs(current->softirqs_raised);
+               unsigned int pending, mask = (1U << i);
+
+               current->softirqs_raised &= ~mask;
+               local_irq_enable();
+
+               /*
+                * If the lock is contended, we boost the owner to
+                * process the softirq or leave the critical section
+                * now.
+                */
+               lock_softirq(i);
+               local_irq_disable();
+               softirq_set_runner(i);
+               /*
+                * Check with the local_softirq_pending() bits,
+                * whether we need to process this still or if someone
+                * else took care of it.
+                */
+               pending = local_softirq_pending();
+               if (pending & mask) {
+                       set_softirq_pending(pending & ~mask);
+                       do_single_softirq(i);
+               }
+               softirq_clr_runner(i);
+               WARN_ON(current->softirq_nestcnt != 1);
+               local_irq_enable();
+               unlock_softirq(i);
+               local_irq_disable();
+       }
+}
+
+void __local_bh_disable(void)
+{
+       if (++current->softirq_nestcnt == 1)
+               migrate_disable();
+}
+EXPORT_SYMBOL(__local_bh_disable);
+
+void __local_bh_enable(void)
+{
+       if (WARN_ON(current->softirq_nestcnt == 0))
+               return;
+
+       local_irq_disable();
+       if (current->softirq_nestcnt == 1 && current->softirqs_raised)
+               do_current_softirqs();
+       local_irq_enable();
+
+       if (--current->softirq_nestcnt == 0)
+               migrate_enable();
+}
+EXPORT_SYMBOL(__local_bh_enable);
+
+void _local_bh_enable(void)
+{
+       if (WARN_ON(current->softirq_nestcnt == 0))
+               return;
+       if (--current->softirq_nestcnt == 0)
+               migrate_enable();
+}
+EXPORT_SYMBOL(_local_bh_enable);
+
+int in_serving_softirq(void)
+{
+       return current->flags & PF_IN_SOFTIRQ;
+}
+EXPORT_SYMBOL(in_serving_softirq);
+
+/* Called with preemption disabled */
+static void run_ksoftirqd(unsigned int cpu)
+{
+       local_irq_disable();
+       current->softirq_nestcnt++;
+
+       do_current_softirqs();
+       current->softirq_nestcnt--;
+       local_irq_enable();
+       cond_resched_rcu_qs();
+}
+
+/*
+ * Called from netif_rx_ni(). Preemption enabled, but migration
+ * disabled. So the cpu can't go away under us.
+ */
+void thread_do_softirq(void)
+{
+       if (!in_serving_softirq() && current->softirqs_raised) {
+               current->softirq_nestcnt++;
+               do_current_softirqs();
+               current->softirq_nestcnt--;
+       }
+}
+
+static void do_raise_softirq_irqoff(unsigned int nr)
+{
+       unsigned int mask;
+
+       mask = 1UL << nr;
+
+       trace_softirq_raise(nr);
+       or_softirq_pending(mask);
+
+       /*
+        * If we are not in a hard interrupt and inside a bh disabled
+        * region, we simply raise the flag on current. local_bh_enable()
+        * will make sure that the softirq is executed. Otherwise we
+        * delegate it to ksoftirqd.
+        */
+       if (!in_irq() && current->softirq_nestcnt)
+               current->softirqs_raised |= mask;
+       else if (!__this_cpu_read(ksoftirqd) || !__this_cpu_read(ktimer_softirqd))
+               return;
+
+       if (mask & TIMER_SOFTIRQS)
+               __this_cpu_read(ktimer_softirqd)->softirqs_raised |= mask;
+       else
+               __this_cpu_read(ksoftirqd)->softirqs_raised |= mask;
+}
+
+static void wakeup_proper_softirq(unsigned int nr)
+{
+       if ((1UL << nr) & TIMER_SOFTIRQS)
+               wakeup_timer_softirqd();
+       else
+               wakeup_softirqd();
+}
+
+void __raise_softirq_irqoff(unsigned int nr)
+{
+       do_raise_softirq_irqoff(nr);
+       if (!in_irq() && !current->softirq_nestcnt)
+               wakeup_proper_softirq(nr);
+}
+
+/*
+ * Same as __raise_softirq_irqoff() but will process them in ksoftirqd
+ */
+void __raise_softirq_irqoff_ksoft(unsigned int nr)
+{
+       unsigned int mask;
+
+       if (WARN_ON_ONCE(!__this_cpu_read(ksoftirqd) ||
+                        !__this_cpu_read(ktimer_softirqd)))
+               return;
+       mask = 1UL << nr;
+
+       trace_softirq_raise(nr);
+       or_softirq_pending(mask);
+       if (mask & TIMER_SOFTIRQS)
+               __this_cpu_read(ktimer_softirqd)->softirqs_raised |= mask;
+       else
+               __this_cpu_read(ksoftirqd)->softirqs_raised |= mask;
+       wakeup_proper_softirq(nr);
+}
+
+/*
+ * This function must run with irqs disabled!
+ */
+void raise_softirq_irqoff(unsigned int nr)
+{
+       do_raise_softirq_irqoff(nr);
+
+       /*
+        * If we're in an hard interrupt we let irq return code deal
+        * with the wakeup of ksoftirqd.
+        */
+       if (in_irq())
+               return;
+       /*
+        * If we are in thread context but outside of a bh disabled
+        * region, we need to wake ksoftirqd as well.
+        *
+        * CHECKME: Some of the places which do that could be wrapped
+        * into local_bh_disable/enable pairs. Though it's unclear
+        * whether this is worth the effort. To find those places just
+        * raise a WARN() if the condition is met.
+        */
+       if (!current->softirq_nestcnt)
+               wakeup_proper_softirq(nr);
+}
+
+static inline int ksoftirqd_softirq_pending(void)
+{
+       return current->softirqs_raised;
+}
+
+static inline void local_bh_disable_nort(void) { }
+static inline void _local_bh_enable_nort(void) { }
+
+static inline void ksoftirqd_set_sched_params(unsigned int cpu)
+{
+       /* Take over all but timer pending softirqs when starting */
+       local_irq_disable();
+       current->softirqs_raised = local_softirq_pending() & ~TIMER_SOFTIRQS;
+       local_irq_enable();
+}
+
+static inline void ktimer_softirqd_set_sched_params(unsigned int cpu)
+{
+       struct sched_param param = { .sched_priority = 1 };
+
+       sched_setscheduler(current, SCHED_FIFO, &param);
+
+       /* Take over timer pending softirqs when starting */
+       local_irq_disable();
+       current->softirqs_raised = local_softirq_pending() & TIMER_SOFTIRQS;
+       local_irq_enable();
+}
+
+static inline void ktimer_softirqd_clr_sched_params(unsigned int cpu,
+                                                   bool online)
+{
+       struct sched_param param = { .sched_priority = 0 };
+
+       sched_setscheduler(current, SCHED_NORMAL, &param);
+}
+
+static int ktimer_softirqd_should_run(unsigned int cpu)
+{
+       return current->softirqs_raised;
+}
+
+#endif /* PREEMPT_RT_FULL */
+/*
  * Enter an interrupt context.
  */
 void irq_enter(void)
@@ -360,9 +803,9 @@ void irq_enter(void)
                 * Prevent raise_softirq from needlessly waking up ksoftirqd
                 * here, as softirq will be serviced on return from interrupt.
                 */
-               local_bh_disable();
+               local_bh_disable_nort();
                tick_irq_enter();
-               _local_bh_enable();
+               _local_bh_enable_nort();
        }
 
        __irq_enter();
@@ -370,6 +813,7 @@ void irq_enter(void)
 
 static inline void invoke_softirq(void)
 {
+#ifndef CONFIG_PREEMPT_RT_FULL
        if (ksoftirqd_running(local_softirq_pending()))
                return;
 
@@ -392,6 +836,18 @@ static inline void invoke_softirq(void)
        } else {
                wakeup_softirqd();
        }
+#else /* PREEMPT_RT_FULL */
+       unsigned long flags;
+
+       local_irq_save(flags);
+       if (__this_cpu_read(ksoftirqd) &&
+                       __this_cpu_read(ksoftirqd)->softirqs_raised)
+               wakeup_softirqd();
+       if (__this_cpu_read(ktimer_softirqd) &&
+                       __this_cpu_read(ktimer_softirqd)->softirqs_raised)
+               wakeup_timer_softirqd();
+       local_irq_restore(flags);
+#endif
 }
 
 static inline void tick_irq_exit(void)
@@ -428,26 +884,6 @@ void irq_exit(void)
        trace_hardirq_exit(); /* must be last! */
 }
 
-/*
- * This function must run with irqs disabled!
- */
-inline void raise_softirq_irqoff(unsigned int nr)
-{
-       __raise_softirq_irqoff(nr);
-
-       /*
-        * If we're in an interrupt or softirq, we're done
-        * (this also catches softirq-disabled code). We will
-        * actually run the softirq once we return from
-        * the irq or softirq.
-        *
-        * Otherwise we wake up ksoftirqd to make sure we
-        * schedule the softirq soon.
-        */
-       if (!in_interrupt())
-               wakeup_softirqd();
-}
-
 void raise_softirq(unsigned int nr)
 {
        unsigned long flags;
@@ -457,12 +893,6 @@ void raise_softirq(unsigned int nr)
        local_irq_restore(flags);
 }
 
-void __raise_softirq_irqoff(unsigned int nr)
-{
-       trace_softirq_raise(nr);
-       or_softirq_pending(1UL << nr);
-}
-
 void open_softirq(int nr, void (*action)(struct softirq_action *))
 {
        softirq_vec[nr].action = action;
@@ -479,15 +909,45 @@ struct tasklet_head {
 static DEFINE_PER_CPU(struct tasklet_head, tasklet_vec);
 static DEFINE_PER_CPU(struct tasklet_head, tasklet_hi_vec);
 
+static void inline
+__tasklet_common_schedule(struct tasklet_struct *t, struct tasklet_head *head, unsigned int nr)
+{
+       if (tasklet_trylock(t)) {
+again:
+               /* We may have been preempted before tasklet_trylock
+                * and __tasklet_action may have already run.
+                * So double check the sched bit while the takslet
+                * is locked before adding it to the list.
+                */
+               if (test_bit(TASKLET_STATE_SCHED, &t->state)) {
+                       t->next = NULL;
+                       *head->tail = t;
+                       head->tail = &(t->next);
+                       raise_softirq_irqoff(nr);
+                       tasklet_unlock(t);
+               } else {
+                       /* This is subtle. If we hit the corner case above
+                        * It is possible that we get preempted right here,
+                        * and another task has successfully called
+                        * tasklet_schedule(), then this function, and
+                        * failed on the trylock. Thus we must be sure
+                        * before releasing the tasklet lock, that the
+                        * SCHED_BIT is clear. Otherwise the tasklet
+                        * may get its SCHED_BIT set, but not added to the
+                        * list
+                        */
+                       if (!tasklet_tryunlock(t))
+                               goto again;
+               }
+       }
+}
+
 void __tasklet_schedule(struct tasklet_struct *t)
 {
        unsigned long flags;
 
        local_irq_save(flags);
-       t->next = NULL;
-       *__this_cpu_read(tasklet_vec.tail) = t;
-       __this_cpu_write(tasklet_vec.tail, &(t->next));
-       raise_softirq_irqoff(TASKLET_SOFTIRQ);
+       __tasklet_common_schedule(t, this_cpu_ptr(&tasklet_vec), TASKLET_SOFTIRQ);
        local_irq_restore(flags);
 }
 EXPORT_SYMBOL(__tasklet_schedule);
@@ -497,10 +957,7 @@ void __tasklet_hi_schedule(struct tasklet_struct *t)
        unsigned long flags;
 
        local_irq_save(flags);
-       t->next = NULL;
-       *__this_cpu_read(tasklet_hi_vec.tail) = t;
-       __this_cpu_write(tasklet_hi_vec.tail,  &(t->next));
-       raise_softirq_irqoff(HI_SOFTIRQ);
+       __tasklet_common_schedule(t, this_cpu_ptr(&tasklet_hi_vec), HI_SOFTIRQ);
        local_irq_restore(flags);
 }
 EXPORT_SYMBOL(__tasklet_hi_schedule);
@@ -509,82 +966,122 @@ void __tasklet_hi_schedule_first(struct tasklet_struct *t)
 {
        BUG_ON(!irqs_disabled());
 
-       t->next = __this_cpu_read(tasklet_hi_vec.head);
-       __this_cpu_write(tasklet_hi_vec.head, t);
-       __raise_softirq_irqoff(HI_SOFTIRQ);
+       __tasklet_hi_schedule(t);
 }
 EXPORT_SYMBOL(__tasklet_hi_schedule_first);
 
-static __latent_entropy void tasklet_action(struct softirq_action *a)
+void  tasklet_enable(struct tasklet_struct *t)
 {
-       struct tasklet_struct *list;
+       if (!atomic_dec_and_test(&t->count))
+               return;
+       if (test_and_clear_bit(TASKLET_STATE_PENDING, &t->state))
+               tasklet_schedule(t);
+}
+EXPORT_SYMBOL(tasklet_enable);
 
-       local_irq_disable();
-       list = __this_cpu_read(tasklet_vec.head);
-       __this_cpu_write(tasklet_vec.head, NULL);
-       __this_cpu_write(tasklet_vec.tail, this_cpu_ptr(&tasklet_vec.head));
-       local_irq_enable();
+static void __tasklet_action(struct softirq_action *a,
+                            struct tasklet_struct *list)
+{
+       int loops = 1000000;
 
        while (list) {
                struct tasklet_struct *t = list;
 
                list = list->next;
 
-               if (tasklet_trylock(t)) {
-                       if (!atomic_read(&t->count)) {
-                               if (!test_and_clear_bit(TASKLET_STATE_SCHED,
-                                                       &t->state))
-                                       BUG();
-                               t->func(t->data);
-                               tasklet_unlock(t);
-                               continue;
-                       }
-                       tasklet_unlock(t);
+               /*
+                * Should always succeed - after a tasklist got on the
+                * list (after getting the SCHED bit set from 0 to 1),
+                * nothing but the tasklet softirq it got queued to can
+                * lock it:
+                */
+               if (!tasklet_trylock(t)) {
+                       WARN_ON(1);
+                       continue;
                }
 
-               local_irq_disable();
                t->next = NULL;
-               *__this_cpu_read(tasklet_vec.tail) = t;
-               __this_cpu_write(tasklet_vec.tail, &(t->next));
-               __raise_softirq_irqoff(TASKLET_SOFTIRQ);
-               local_irq_enable();
+
+               /*
+                * If we cannot handle the tasklet because it's disabled,
+                * mark it as pending. tasklet_enable() will later
+                * re-schedule the tasklet.
+                */
+               if (unlikely(atomic_read(&t->count))) {
+out_disabled:
+                       /* implicit unlock: */
+                       wmb();
+                       t->state = TASKLET_STATEF_PENDING;
+                       continue;
+               }
+
+               /*
+                * After this point on the tasklet might be rescheduled
+                * on another CPU, but it can only be added to another
+                * CPU's tasklet list if we unlock the tasklet (which we
+                * dont do yet).
+                */
+               if (!test_and_clear_bit(TASKLET_STATE_SCHED, &t->state))
+                       WARN_ON(1);
+
+again:
+               t->func(t->data);
+
+               /*
+                * Try to unlock the tasklet. We must use cmpxchg, because
+                * another CPU might have scheduled or disabled the tasklet.
+                * We only allow the STATE_RUN -> 0 transition here.
+                */
+               while (!tasklet_tryunlock(t)) {
+                       /*
+                        * If it got disabled meanwhile, bail out:
+                        */
+                       if (atomic_read(&t->count))
+                               goto out_disabled;
+                       /*
+                        * If it got scheduled meanwhile, re-execute
+                        * the tasklet function:
+                        */
+                       if (test_and_clear_bit(TASKLET_STATE_SCHED, &t->state))
+                               goto again;
+                       if (!--loops) {
+                               printk("hm, tasklet state: %08lx\n", t->state);
+                               WARN_ON(1);
+                               tasklet_unlock(t);
+                               break;
+                       }
+               }
        }
 }
 
+static void tasklet_action(struct softirq_action *a)
+{
+       struct tasklet_struct *list;
+
+       local_irq_disable();
+
+       list = __this_cpu_read(tasklet_vec.head);
+       __this_cpu_write(tasklet_vec.head, NULL);
+       __this_cpu_write(tasklet_vec.tail, this_cpu_ptr(&tasklet_vec.head));
+
+       local_irq_enable();
+
+       __tasklet_action(a, list);
+}
+
 static __latent_entropy void tasklet_hi_action(struct softirq_action *a)
 {
        struct tasklet_struct *list;
 
        local_irq_disable();
+
        list = __this_cpu_read(tasklet_hi_vec.head);
        __this_cpu_write(tasklet_hi_vec.head, NULL);
        __this_cpu_write(tasklet_hi_vec.tail, this_cpu_ptr(&tasklet_hi_vec.head));
-       local_irq_enable();
 
-       while (list) {
-               struct tasklet_struct *t = list;
-
-               list = list->next;
-
-               if (tasklet_trylock(t)) {
-                       if (!atomic_read(&t->count)) {
-                               if (!test_and_clear_bit(TASKLET_STATE_SCHED,
-                                                       &t->state))
-                                       BUG();
-                               t->func(t->data);
-                               tasklet_unlock(t);
-                               continue;
-                       }
-                       tasklet_unlock(t);
-               }
+       local_irq_enable();
 
-               local_irq_disable();
-               t->next = NULL;
-               *__this_cpu_read(tasklet_hi_vec.tail) = t;
-               __this_cpu_write(tasklet_hi_vec.tail, &(t->next));
-               __raise_softirq_irqoff(HI_SOFTIRQ);
-               local_irq_enable();
-       }
+       __tasklet_action(a, list);
 }
 
 void tasklet_init(struct tasklet_struct *t,
@@ -605,7 +1102,7 @@ void tasklet_kill(struct tasklet_struct *t)
 
        while (test_and_set_bit(TASKLET_STATE_SCHED, &t->state)) {
                do {
-                       yield();
+                       msleep(1);
                } while (test_bit(TASKLET_STATE_SCHED, &t->state));
        }
        tasklet_unlock_wait(t);
@@ -679,25 +1176,26 @@ void __init softirq_init(void)
        open_softirq(HI_SOFTIRQ, tasklet_hi_action);
 }
 
-static int ksoftirqd_should_run(unsigned int cpu)
-{
-       return local_softirq_pending();
-}
-
-static void run_ksoftirqd(unsigned int cpu)
+#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT_FULL)
+void tasklet_unlock_wait(struct tasklet_struct *t)
 {
-       local_irq_disable();
-       if (local_softirq_pending()) {
+       while (test_bit(TASKLET_STATE_RUN, &(t)->state)) {
                /*
-                * We can safely run softirq on inline stack, as we are not deep
-                * in the task stack here.
+                * Hack for now to avoid this busy-loop:
                 */
-               __do_softirq();
-               local_irq_enable();
-               cond_resched_rcu_qs();
-               return;
+#ifdef CONFIG_PREEMPT_RT_FULL
+               msleep(1);
+#else
+               barrier();
+#endif
        }
-       local_irq_enable();
+}
+EXPORT_SYMBOL(tasklet_unlock_wait);
+#endif
+
+static int ksoftirqd_should_run(unsigned int cpu)
+{
+       return ksoftirqd_softirq_pending();
 }
 
 #ifdef CONFIG_HOTPLUG_CPU
@@ -764,17 +1262,31 @@ static int takeover_tasklets(unsigned int cpu)
 
 static struct smp_hotplug_thread softirq_threads = {
        .store                  = &ksoftirqd,
+       .setup                  = ksoftirqd_set_sched_params,
        .thread_should_run      = ksoftirqd_should_run,
        .thread_fn              = run_ksoftirqd,
        .thread_comm            = "ksoftirqd/%u",
 };
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+static struct smp_hotplug_thread softirq_timer_threads = {
+       .store                  = &ktimer_softirqd,
+       .setup                  = ktimer_softirqd_set_sched_params,
+       .cleanup                = ktimer_softirqd_clr_sched_params,
+       .thread_should_run      = ktimer_softirqd_should_run,
+       .thread_fn              = run_ksoftirqd,
+       .thread_comm            = "ktimersoftd/%u",
+};
+#endif
+
 static __init int spawn_ksoftirqd(void)
 {
        cpuhp_setup_state_nocalls(CPUHP_SOFTIRQ_DEAD, "softirq:dead", NULL,
                                  takeover_tasklets);
        BUG_ON(smpboot_register_percpu_thread(&softirq_threads));
-
+#ifdef CONFIG_PREEMPT_RT_FULL
+       BUG_ON(smpboot_register_percpu_thread(&softirq_timer_threads));
+#endif
        return 0;
 }
 early_initcall(spawn_ksoftirqd);
index 9b8cd7e..6b29525 100644 (file)
@@ -475,6 +475,8 @@ repeat:
                struct cpu_stop_done *done = work->done;
                int ret;
 
+               /* XXX */
+
                /* cpu stop callbacks must not sleep, make in_atomic() == T */
                preempt_count_inc();
                ret = fn(arg);
index 6aef4a0..d2e2550 100644 (file)
@@ -407,7 +407,7 @@ int alarm_cancel(struct alarm *alarm)
                int ret = alarm_try_to_cancel(alarm);
                if (ret >= 0)
                        return ret;
-               cpu_relax();
+               hrtimer_wait_for_timer(&alarm->timer);
        }
 }
 EXPORT_SYMBOL_GPL(alarm_cancel);
index f31637c..b01e1fe 100644 (file)
@@ -53,6 +53,7 @@
 #include <asm/uaccess.h>
 
 #include <trace/events/timer.h>
+#include <trace/events/hist.h>
 
 #include "tick-internal.h"
 
@@ -695,6 +696,29 @@ static void hrtimer_switch_to_hres(void)
        retrigger_next_event(NULL);
 }
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+
+static struct swork_event clock_set_delay_work;
+
+static void run_clock_set_delay(struct swork_event *event)
+{
+       clock_was_set();
+}
+
+void clock_was_set_delayed(void)
+{
+       swork_queue(&clock_set_delay_work);
+}
+
+static __init int create_clock_set_delay_thread(void)
+{
+       WARN_ON(swork_get());
+       INIT_SWORK(&clock_set_delay_work, run_clock_set_delay);
+       return 0;
+}
+early_initcall(create_clock_set_delay_thread);
+#else /* PREEMPT_RT_FULL */
+
 static void clock_was_set_work(struct work_struct *work)
 {
        clock_was_set();
@@ -710,6 +734,7 @@ void clock_was_set_delayed(void)
 {
        schedule_work(&hrtimer_work);
 }
+#endif
 
 #else
 
@@ -719,11 +744,8 @@ static inline int hrtimer_is_hres_enabled(void) { return 0; }
 static inline void hrtimer_switch_to_hres(void) { }
 static inline void
 hrtimer_force_reprogram(struct hrtimer_cpu_base *base, int skip_equal) { }
-static inline int hrtimer_reprogram(struct hrtimer *timer,
-                                   struct hrtimer_clock_base *base)
-{
-       return 0;
-}
+static inline void hrtimer_reprogram(struct hrtimer *timer,
+                                    struct hrtimer_clock_base *base) { }
 static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base) { }
 static inline void retrigger_next_event(void *arg) { }
 
@@ -855,6 +877,32 @@ u64 hrtimer_forward(struct hrtimer *timer, ktime_t now, ktime_t interval)
 }
 EXPORT_SYMBOL_GPL(hrtimer_forward);
 
+#ifdef CONFIG_PREEMPT_RT_BASE
+# define wake_up_timer_waiters(b)      wake_up(&(b)->wait)
+
+/**
+ * hrtimer_wait_for_timer - Wait for a running timer
+ *
+ * @timer:     timer to wait for
+ *
+ * The function waits in case the timers callback function is
+ * currently executed on the waitqueue of the timer base. The
+ * waitqueue is woken up after the timer callback function has
+ * finished execution.
+ */
+void hrtimer_wait_for_timer(const struct hrtimer *timer)
+{
+       struct hrtimer_clock_base *base = timer->base;
+
+       if (base && base->cpu_base && !timer->irqsafe)
+               wait_event(base->cpu_base->wait,
+                               !(hrtimer_callback_running(timer)));
+}
+
+#else
+# define wake_up_timer_waiters(b)      do { } while (0)
+#endif
+
 /*
  * enqueue_hrtimer - internal function to (re)start a timer
  *
@@ -898,6 +946,11 @@ static void __remove_hrtimer(struct hrtimer *timer,
        if (!(state & HRTIMER_STATE_ENQUEUED))
                return;
 
+       if (unlikely(!list_empty(&timer->cb_entry))) {
+               list_del_init(&timer->cb_entry);
+               return;
+       }
+
        if (!timerqueue_del(&base->active, &timer->node))
                cpu_base->active_bases &= ~(1 << base->index);
 
@@ -994,7 +1047,16 @@ void hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
        new_base = switch_hrtimer_base(timer, base, mode & HRTIMER_MODE_PINNED);
 
        timer_stats_hrtimer_set_start_info(timer);
+#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
+       {
+               ktime_t now = new_base->get_time();
 
+               if (ktime_to_ns(tim) < ktime_to_ns(now))
+                       timer->praecox = now;
+               else
+                       timer->praecox = ktime_set(0, 0);
+       }
+#endif
        leftmost = enqueue_hrtimer(timer, new_base);
        if (!leftmost)
                goto unlock;
@@ -1066,7 +1128,7 @@ int hrtimer_cancel(struct hrtimer *timer)
 
                if (ret >= 0)
                        return ret;
-               cpu_relax();
+               hrtimer_wait_for_timer(timer);
        }
 }
 EXPORT_SYMBOL_GPL(hrtimer_cancel);
@@ -1147,6 +1209,7 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
 
        base = hrtimer_clockid_to_base(clock_id);
        timer->base = &cpu_base->clock_base[base];
+       INIT_LIST_HEAD(&timer->cb_entry);
        timerqueue_init(&timer->node);
 
 #ifdef CONFIG_TIMER_STATS
@@ -1187,6 +1250,7 @@ bool hrtimer_active(const struct hrtimer *timer)
                seq = raw_read_seqcount_begin(&cpu_base->seq);
 
                if (timer->state != HRTIMER_STATE_INACTIVE ||
+                   cpu_base->running_soft == timer ||
                    cpu_base->running == timer)
                        return true;
 
@@ -1285,10 +1349,112 @@ static void __run_hrtimer(struct hrtimer_cpu_base *cpu_base,
        cpu_base->running = NULL;
 }
 
-static void __hrtimer_run_queues(struct hrtimer_cpu_base *cpu_base, ktime_t now)
+#ifdef CONFIG_PREEMPT_RT_BASE
+static void hrtimer_rt_reprogram(int restart, struct hrtimer *timer,
+                                struct hrtimer_clock_base *base)
+{
+       int leftmost;
+
+       if (restart != HRTIMER_NORESTART &&
+           !(timer->state & HRTIMER_STATE_ENQUEUED)) {
+
+               leftmost = enqueue_hrtimer(timer, base);
+               if (!leftmost)
+                       return;
+#ifdef CONFIG_HIGH_RES_TIMERS
+               if (!hrtimer_is_hres_active(timer)) {
+                       /*
+                        * Kick to reschedule the next tick to handle the new timer
+                        * on dynticks target.
+                        */
+                       if (base->cpu_base->nohz_active)
+                               wake_up_nohz_cpu(base->cpu_base->cpu);
+               } else {
+
+                       hrtimer_reprogram(timer, base);
+               }
+#endif
+       }
+}
+
+/*
+ * The changes in mainline which removed the callback modes from
+ * hrtimer are not yet working with -rt. The non wakeup_process()
+ * based callbacks which involve sleeping locks need to be treated
+ * seperately.
+ */
+static void hrtimer_rt_run_pending(void)
+{
+       enum hrtimer_restart (*fn)(struct hrtimer *);
+       struct hrtimer_cpu_base *cpu_base;
+       struct hrtimer_clock_base *base;
+       struct hrtimer *timer;
+       int index, restart;
+
+       local_irq_disable();
+       cpu_base = &per_cpu(hrtimer_bases, smp_processor_id());
+
+       raw_spin_lock(&cpu_base->lock);
+
+       for (index = 0; index < HRTIMER_MAX_CLOCK_BASES; index++) {
+               base = &cpu_base->clock_base[index];
+
+               while (!list_empty(&base->expired)) {
+                       timer = list_first_entry(&base->expired,
+                                                struct hrtimer, cb_entry);
+
+                       /*
+                        * Same as the above __run_hrtimer function
+                        * just we run with interrupts enabled.
+                        */
+                       debug_deactivate(timer);
+                       cpu_base->running_soft = timer;
+                       raw_write_seqcount_barrier(&cpu_base->seq);
+
+                       __remove_hrtimer(timer, base, HRTIMER_STATE_INACTIVE, 0);
+                       timer_stats_account_hrtimer(timer);
+                       fn = timer->function;
+
+                       raw_spin_unlock_irq(&cpu_base->lock);
+                       restart = fn(timer);
+                       raw_spin_lock_irq(&cpu_base->lock);
+
+                       hrtimer_rt_reprogram(restart, timer, base);
+                       raw_write_seqcount_barrier(&cpu_base->seq);
+
+                       WARN_ON_ONCE(cpu_base->running_soft != timer);
+                       cpu_base->running_soft = NULL;
+               }
+       }
+
+       raw_spin_unlock_irq(&cpu_base->lock);
+
+       wake_up_timer_waiters(cpu_base);
+}
+
+static int hrtimer_rt_defer(struct hrtimer *timer)
+{
+       if (timer->irqsafe)
+               return 0;
+
+       __remove_hrtimer(timer, timer->base, timer->state, 0);
+       list_add_tail(&timer->cb_entry, &timer->base->expired);
+       return 1;
+}
+
+#else
+
+static inline int hrtimer_rt_defer(struct hrtimer *timer) { return 0; }
+
+#endif
+
+static enum hrtimer_restart hrtimer_wakeup(struct hrtimer *timer);
+
+static int __hrtimer_run_queues(struct hrtimer_cpu_base *cpu_base, ktime_t now)
 {
        struct hrtimer_clock_base *base = cpu_base->clock_base;
        unsigned int active = cpu_base->active_bases;
+       int raise = 0;
 
        for (; active; base++, active >>= 1) {
                struct timerqueue_node *node;
@@ -1304,6 +1470,15 @@ static void __hrtimer_run_queues(struct hrtimer_cpu_base *cpu_base, ktime_t now)
 
                        timer = container_of(node, struct hrtimer, node);
 
+                       trace_hrtimer_interrupt(raw_smp_processor_id(),
+                           ktime_to_ns(ktime_sub(ktime_to_ns(timer->praecox) ?
+                               timer->praecox : hrtimer_get_expires(timer),
+                               basenow)),
+                           current,
+                           timer->function == hrtimer_wakeup ?
+                           container_of(timer, struct hrtimer_sleeper,
+                               timer)->task : NULL);
+
                        /*
                         * The immediate goal for using the softexpires is
                         * minimizing wakeups, not running timers at the
@@ -1319,9 +1494,13 @@ static void __hrtimer_run_queues(struct hrtimer_cpu_base *cpu_base, ktime_t now)
                        if (basenow.tv64 < hrtimer_get_softexpires_tv64(timer))
                                break;
 
-                       __run_hrtimer(cpu_base, base, timer, &basenow);
+                       if (!hrtimer_rt_defer(timer))
+                               __run_hrtimer(cpu_base, base, timer, &basenow);
+                       else
+                               raise = 1;
                }
        }
+       return raise;
 }
 
 #ifdef CONFIG_HIGH_RES_TIMERS
@@ -1335,6 +1514,7 @@ void hrtimer_interrupt(struct clock_event_device *dev)
        struct hrtimer_cpu_base *cpu_base = this_cpu_ptr(&hrtimer_bases);
        ktime_t expires_next, now, entry_time, delta;
        int retries = 0;
+       int raise;
 
        BUG_ON(!cpu_base->hres_active);
        cpu_base->nr_events++;
@@ -1353,7 +1533,7 @@ retry:
         */
        cpu_base->expires_next.tv64 = KTIME_MAX;
 
-       __hrtimer_run_queues(cpu_base, now);
+       raise = __hrtimer_run_queues(cpu_base, now);
 
        /* Reevaluate the clock bases for the next expiry */
        expires_next = __hrtimer_get_next_event(cpu_base);
@@ -1364,6 +1544,8 @@ retry:
        cpu_base->expires_next = expires_next;
        cpu_base->in_hrtirq = 0;
        raw_spin_unlock(&cpu_base->lock);
+       if (raise)
+               raise_softirq_irqoff(HRTIMER_SOFTIRQ);
 
        /* Reprogramming necessary ? */
        if (!tick_program_event(expires_next, 0)) {
@@ -1443,6 +1625,7 @@ void hrtimer_run_queues(void)
 {
        struct hrtimer_cpu_base *cpu_base = this_cpu_ptr(&hrtimer_bases);
        ktime_t now;
+       int raise;
 
        if (__hrtimer_hres_active(cpu_base))
                return;
@@ -1461,8 +1644,10 @@ void hrtimer_run_queues(void)
 
        raw_spin_lock(&cpu_base->lock);
        now = hrtimer_update_base(cpu_base);
-       __hrtimer_run_queues(cpu_base, now);
+       raise = __hrtimer_run_queues(cpu_base, now);
        raw_spin_unlock(&cpu_base->lock);
+       if (raise)
+               raise_softirq_irqoff(HRTIMER_SOFTIRQ);
 }
 
 /*
@@ -1484,16 +1669,18 @@ static enum hrtimer_restart hrtimer_wakeup(struct hrtimer *timer)
 void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, struct task_struct *task)
 {
        sl->timer.function = hrtimer_wakeup;
+       sl->timer.irqsafe = 1;
        sl->task = task;
 }
 EXPORT_SYMBOL_GPL(hrtimer_init_sleeper);
 
-static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mode)
+static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mode,
+                               unsigned long state)
 {
        hrtimer_init_sleeper(t, current);
 
        do {
-               set_current_state(TASK_INTERRUPTIBLE);
+               set_current_state(state);
                hrtimer_start_expires(&t->timer, mode);
 
                if (likely(t->task))
@@ -1535,7 +1722,8 @@ long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
                                HRTIMER_MODE_ABS);
        hrtimer_set_expires_tv64(&t.timer, restart->nanosleep.expires);
 
-       if (do_nanosleep(&t, HRTIMER_MODE_ABS))
+       /* cpu_chill() does not care about restart state. */
+       if (do_nanosleep(&t, HRTIMER_MODE_ABS, TASK_INTERRUPTIBLE))
                goto out;
 
        rmtp = restart->nanosleep.rmtp;
@@ -1552,8 +1740,10 @@ out:
        return ret;
 }
 
-long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
-                      const enum hrtimer_mode mode, const clockid_t clockid)
+static long
+__hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
+                   const enum hrtimer_mode mode, const clockid_t clockid,
+                   unsigned long state)
 {
        struct restart_block *restart;
        struct hrtimer_sleeper t;
@@ -1566,7 +1756,7 @@ long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
 
        hrtimer_init_on_stack(&t.timer, clockid, mode);
        hrtimer_set_expires_range_ns(&t.timer, timespec_to_ktime(*rqtp), slack);
-       if (do_nanosleep(&t, mode))
+       if (do_nanosleep(&t, mode, state))
                goto out;
 
        /* Absolute timers do not update the rmtp value and restart: */
@@ -1593,6 +1783,12 @@ out:
        return ret;
 }
 
+long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
+                      const enum hrtimer_mode mode, const clockid_t clockid)
+{
+       return __hrtimer_nanosleep(rqtp, rmtp, mode, clockid, TASK_INTERRUPTIBLE);
+}
+
 SYSCALL_DEFINE2(nanosleep, struct timespec __user *, rqtp,
                struct timespec __user *, rmtp)
 {
@@ -1607,6 +1803,26 @@ SYSCALL_DEFINE2(nanosleep, struct timespec __user *, rqtp,
        return hrtimer_nanosleep(&tu, rmtp, HRTIMER_MODE_REL, CLOCK_MONOTONIC);
 }
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+/*
+ * Sleep for 1 ms in hope whoever holds what we want will let it go.
+ */
+void cpu_chill(void)
+{
+       struct timespec tu = {
+               .tv_nsec = NSEC_PER_MSEC,
+       };
+       unsigned int freeze_flag = current->flags & PF_NOFREEZE;
+
+       current->flags |= PF_NOFREEZE;
+       __hrtimer_nanosleep(&tu, NULL, HRTIMER_MODE_REL, CLOCK_MONOTONIC,
+                           TASK_UNINTERRUPTIBLE);
+       if (!freeze_flag)
+               current->flags &= ~PF_NOFREEZE;
+}
+EXPORT_SYMBOL(cpu_chill);
+#endif
+
 /*
  * Functions related to boot-time initialization:
  */
@@ -1618,17 +1834,21 @@ int hrtimers_prepare_cpu(unsigned int cpu)
        for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
                cpu_base->clock_base[i].cpu_base = cpu_base;
                timerqueue_init_head(&cpu_base->clock_base[i].active);
+               INIT_LIST_HEAD(&cpu_base->clock_base[i].expired);
        }
 
        cpu_base->active_bases = 0;
        cpu_base->cpu = cpu;
        hrtimer_init_hres(cpu_base);
+#ifdef CONFIG_PREEMPT_RT_BASE
+       init_waitqueue_head(&cpu_base->wait);
+#endif
        return 0;
 }
 
 #ifdef CONFIG_HOTPLUG_CPU
 
-static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base,
+static int migrate_hrtimer_list(struct hrtimer_clock_base *old_base,
                                struct hrtimer_clock_base *new_base)
 {
        struct hrtimer *timer;
@@ -1656,12 +1876,21 @@ static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base,
                 */
                enqueue_hrtimer(timer, new_base);
        }
+#ifdef CONFIG_PREEMPT_RT_BASE
+       list_splice_tail(&old_base->expired, &new_base->expired);
+       /*
+        * Tell the caller to raise HRTIMER_SOFTIRQ.  We can't safely
+        * acquire ktimersoftd->pi_lock while the base lock is held.
+        */
+       return !list_empty(&new_base->expired);
+#endif
+       return 0;
 }
 
 int hrtimers_dead_cpu(unsigned int scpu)
 {
        struct hrtimer_cpu_base *old_base, *new_base;
-       int i;
+       int i, raise = 0;
 
        BUG_ON(cpu_online(scpu));
        tick_cancel_sched_timer(scpu);
@@ -1677,13 +1906,16 @@ int hrtimers_dead_cpu(unsigned int scpu)
        raw_spin_lock_nested(&old_base->lock, SINGLE_DEPTH_NESTING);
 
        for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
-               migrate_hrtimer_list(&old_base->clock_base[i],
-                                    &new_base->clock_base[i]);
+               raise |= migrate_hrtimer_list(&old_base->clock_base[i],
+                                             &new_base->clock_base[i]);
        }
 
        raw_spin_unlock(&old_base->lock);
        raw_spin_unlock(&new_base->lock);
 
+       if (raise)
+               raise_softirq_irqoff(HRTIMER_SOFTIRQ);
+
        /* Check, if we got expired work to do */
        __hrtimer_peek_ahead_timers();
        local_irq_enable();
@@ -1692,9 +1924,26 @@ int hrtimers_dead_cpu(unsigned int scpu)
 
 #endif /* CONFIG_HOTPLUG_CPU */
 
+#ifdef CONFIG_PREEMPT_RT_BASE
+
+static void run_hrtimer_softirq(struct softirq_action *h)
+{
+       hrtimer_rt_run_pending();
+}
+
+static void hrtimers_open_softirq(void)
+{
+       open_softirq(HRTIMER_SOFTIRQ, run_hrtimer_softirq);
+}
+
+#else
+static void hrtimers_open_softirq(void) { }
+#endif
+
 void __init hrtimers_init(void)
 {
        hrtimers_prepare_cpu(smp_processor_id());
+       hrtimers_open_softirq();
 }
 
 /**
index 1d5c720..184de67 100644 (file)
@@ -213,6 +213,7 @@ again:
                /* We are sharing ->siglock with it_real_fn() */
                if (hrtimer_try_to_cancel(timer) < 0) {
                        spin_unlock_irq(&tsk->sighand->siglock);
+                       hrtimer_wait_for_timer(&tsk->signal->real_timer);
                        goto again;
                }
                expires = timeval_to_ktime(value->it_value);
index 555e21f..a5d6435 100644 (file)
@@ -74,7 +74,8 @@ static struct clocksource clocksource_jiffies = {
        .max_cycles     = 10,
 };
 
-__cacheline_aligned_in_smp DEFINE_SEQLOCK(jiffies_lock);
+__cacheline_aligned_in_smp DEFINE_RAW_SPINLOCK(jiffies_lock);
+__cacheline_aligned_in_smp seqcount_t jiffies_seq;
 
 #if (BITS_PER_LONG < 64)
 u64 get_jiffies_64(void)
@@ -83,9 +84,9 @@ u64 get_jiffies_64(void)
        u64 ret;
 
        do {
-               seq = read_seqbegin(&jiffies_lock);
+               seq = read_seqcount_begin(&jiffies_seq);
                ret = jiffies_64;
-       } while (read_seqretry(&jiffies_lock, seq));
+       } while (read_seqcount_retry(&jiffies_seq, seq));
        return ret;
 }
 EXPORT_SYMBOL(get_jiffies_64);
index 1ac6189..c64b187 100644 (file)
@@ -3,6 +3,7 @@
  */
 
 #include <linux/sched.h>
+#include <linux/sched/rt.h>
 #include <linux/posix-timers.h>
 #include <linux/errno.h>
 #include <linux/math64.h>
@@ -620,7 +621,7 @@ static int posix_cpu_timer_set(struct k_itimer *timer, int timer_flags,
        /*
         * Disarm any old timer after extracting its expiry time.
         */
-       WARN_ON_ONCE(!irqs_disabled());
+       WARN_ON_ONCE_NONRT(!irqs_disabled());
 
        ret = 0;
        old_incr = timer->it.cpu.incr;
@@ -1064,7 +1065,7 @@ void posix_cpu_timer_schedule(struct k_itimer *timer)
        /*
         * Now re-arm for the new expiry time.
         */
-       WARN_ON_ONCE(!irqs_disabled());
+       WARN_ON_ONCE_NONRT(!irqs_disabled());
        arm_timer(timer);
        unlock_task_sighand(p, &flags);
 
@@ -1153,13 +1154,13 @@ static inline int fastpath_timer_check(struct task_struct *tsk)
  * already updated our counts.  We need to check if any timers fire now.
  * Interrupts are disabled.
  */
-void run_posix_cpu_timers(struct task_struct *tsk)
+static void __run_posix_cpu_timers(struct task_struct *tsk)
 {
        LIST_HEAD(firing);
        struct k_itimer *timer, *next;
        unsigned long flags;
 
-       WARN_ON_ONCE(!irqs_disabled());
+       WARN_ON_ONCE_NONRT(!irqs_disabled());
 
        /*
         * The fast path checks that there are no expired thread or thread
@@ -1213,6 +1214,190 @@ void run_posix_cpu_timers(struct task_struct *tsk)
        }
 }
 
+#ifdef CONFIG_PREEMPT_RT_BASE
+#include <linux/kthread.h>
+#include <linux/cpu.h>
+DEFINE_PER_CPU(struct task_struct *, posix_timer_task);
+DEFINE_PER_CPU(struct task_struct *, posix_timer_tasklist);
+
+static int posix_cpu_timers_thread(void *data)
+{
+       int cpu = (long)data;
+
+       BUG_ON(per_cpu(posix_timer_task,cpu) != current);
+
+       while (!kthread_should_stop()) {
+               struct task_struct *tsk = NULL;
+               struct task_struct *next = NULL;
+
+               if (cpu_is_offline(cpu))
+                       goto wait_to_die;
+
+               /* grab task list */
+               raw_local_irq_disable();
+               tsk = per_cpu(posix_timer_tasklist, cpu);
+               per_cpu(posix_timer_tasklist, cpu) = NULL;
+               raw_local_irq_enable();
+
+               /* its possible the list is empty, just return */
+               if (!tsk) {
+                       set_current_state(TASK_INTERRUPTIBLE);
+                       schedule();
+                       __set_current_state(TASK_RUNNING);
+                       continue;
+               }
+
+               /* Process task list */
+               while (1) {
+                       /* save next */
+                       next = tsk->posix_timer_list;
+
+                       /* run the task timers, clear its ptr and
+                        * unreference it
+                        */
+                       __run_posix_cpu_timers(tsk);
+                       tsk->posix_timer_list = NULL;
+                       put_task_struct(tsk);
+
+                       /* check if this is the last on the list */
+                       if (next == tsk)
+                               break;
+                       tsk = next;
+               }
+       }
+       return 0;
+
+wait_to_die:
+       /* Wait for kthread_stop */
+       set_current_state(TASK_INTERRUPTIBLE);
+       while (!kthread_should_stop()) {
+               schedule();
+               set_current_state(TASK_INTERRUPTIBLE);
+       }
+       __set_current_state(TASK_RUNNING);
+       return 0;
+}
+
+static inline int __fastpath_timer_check(struct task_struct *tsk)
+{
+       /* tsk == current, ensure it is safe to use ->signal/sighand */
+       if (unlikely(tsk->exit_state))
+               return 0;
+
+       if (!task_cputime_zero(&tsk->cputime_expires))
+                       return 1;
+
+       if (!task_cputime_zero(&tsk->signal->cputime_expires))
+                       return 1;
+
+       return 0;
+}
+
+void run_posix_cpu_timers(struct task_struct *tsk)
+{
+       unsigned long cpu = smp_processor_id();
+       struct task_struct *tasklist;
+
+       BUG_ON(!irqs_disabled());
+       if(!per_cpu(posix_timer_task, cpu))
+               return;
+       /* get per-cpu references */
+       tasklist = per_cpu(posix_timer_tasklist, cpu);
+
+       /* check to see if we're already queued */
+       if (!tsk->posix_timer_list && __fastpath_timer_check(tsk)) {
+               get_task_struct(tsk);
+               if (tasklist) {
+                       tsk->posix_timer_list = tasklist;
+               } else {
+                       /*
+                        * The list is terminated by a self-pointing
+                        * task_struct
+                        */
+                       tsk->posix_timer_list = tsk;
+               }
+               per_cpu(posix_timer_tasklist, cpu) = tsk;
+
+               wake_up_process(per_cpu(posix_timer_task, cpu));
+       }
+}
+
+/*
+ * posix_cpu_thread_call - callback that gets triggered when a CPU is added.
+ * Here we can start up the necessary migration thread for the new CPU.
+ */
+static int posix_cpu_thread_call(struct notifier_block *nfb,
+                                unsigned long action, void *hcpu)
+{
+       int cpu = (long)hcpu;
+       struct task_struct *p;
+       struct sched_param param;
+
+       switch (action) {
+       case CPU_UP_PREPARE:
+               p = kthread_create(posix_cpu_timers_thread, hcpu,
+                                       "posixcputmr/%d",cpu);
+               if (IS_ERR(p))
+                       return NOTIFY_BAD;
+               p->flags |= PF_NOFREEZE;
+               kthread_bind(p, cpu);
+               /* Must be high prio to avoid getting starved */
+               param.sched_priority = MAX_RT_PRIO-1;
+               sched_setscheduler(p, SCHED_FIFO, &param);
+               per_cpu(posix_timer_task,cpu) = p;
+               break;
+       case CPU_ONLINE:
+               /* Strictly unneccessary, as first user will wake it. */
+               wake_up_process(per_cpu(posix_timer_task,cpu));
+               break;
+#ifdef CONFIG_HOTPLUG_CPU
+       case CPU_UP_CANCELED:
+               /* Unbind it from offline cpu so it can run.  Fall thru. */
+               kthread_bind(per_cpu(posix_timer_task, cpu),
+                            cpumask_any(cpu_online_mask));
+               kthread_stop(per_cpu(posix_timer_task,cpu));
+               per_cpu(posix_timer_task,cpu) = NULL;
+               break;
+       case CPU_DEAD:
+               kthread_stop(per_cpu(posix_timer_task,cpu));
+               per_cpu(posix_timer_task,cpu) = NULL;
+               break;
+#endif
+       }
+       return NOTIFY_OK;
+}
+
+/* Register at highest priority so that task migration (migrate_all_tasks)
+ * happens before everything else.
+ */
+static struct notifier_block posix_cpu_thread_notifier = {
+       .notifier_call = posix_cpu_thread_call,
+       .priority = 10
+};
+
+static int __init posix_cpu_thread_init(void)
+{
+       void *hcpu = (void *)(long)smp_processor_id();
+       /* Start one for boot CPU. */
+       unsigned long cpu;
+
+       /* init the per-cpu posix_timer_tasklets */
+       for_each_possible_cpu(cpu)
+               per_cpu(posix_timer_tasklist, cpu) = NULL;
+
+       posix_cpu_thread_call(&posix_cpu_thread_notifier, CPU_UP_PREPARE, hcpu);
+       posix_cpu_thread_call(&posix_cpu_thread_notifier, CPU_ONLINE, hcpu);
+       register_cpu_notifier(&posix_cpu_thread_notifier);
+       return 0;
+}
+early_initcall(posix_cpu_thread_init);
+#else /* CONFIG_PREEMPT_RT_BASE */
+void run_posix_cpu_timers(struct task_struct *tsk)
+{
+       __run_posix_cpu_timers(tsk);
+}
+#endif /* CONFIG_PREEMPT_RT_BASE */
+
 /*
  * Set one of the process-wide special case CPU timers or RLIMIT_CPU.
  * The tsk->sighand->siglock must be held by the caller.
index 0e6ed2e..d6d6c19 100644 (file)
@@ -526,6 +526,9 @@ static struct pid *good_sigevent(sigevent_t * event)
        case SIGEV_THREAD:
                if (event->sigev_signo <= 0 || event->sigev_signo > SIGRTMAX)
                        return NULL;
+               if (sig_kernel_only(event->sigev_signo) ||
+                   sig_kernel_coredump(event->sigev_signo))
+                       return NULL;
                /* FALLTHRU */
        case SIGEV_NONE:
                return task_pid(rtn);
@@ -574,7 +577,7 @@ static struct k_itimer * alloc_posix_timer(void)
 
 static void k_itimer_rcu_free(struct rcu_head *head)
 {
-       struct k_itimer *tmr = container_of(head, struct k_itimer, it.rcu);
+       struct k_itimer *tmr = container_of(head, struct k_itimer, rcu);
 
        kmem_cache_free(posix_timers_cache, tmr);
 }
@@ -591,7 +594,7 @@ static void release_posix_timer(struct k_itimer *tmr, int it_id_set)
        }
        put_pid(tmr->it_pid);
        sigqueue_free(tmr->sigq);
-       call_rcu(&tmr->it.rcu, k_itimer_rcu_free);
+       call_rcu(&tmr->rcu, k_itimer_rcu_free);
 }
 
 static struct k_clock *clockid_to_kclock(const clockid_t id)
@@ -839,6 +842,20 @@ SYSCALL_DEFINE1(timer_getoverrun, timer_t, timer_id)
        return overrun;
 }
 
+/*
+ * Protected by RCU!
+ */
+static void timer_wait_for_callback(struct k_clock *kc, struct k_itimer *timr)
+{
+#ifdef CONFIG_PREEMPT_RT_FULL
+       if (kc->timer_set == common_timer_set)
+               hrtimer_wait_for_timer(&timr->it.real.timer);
+       else
+               /* FIXME: Whacky hack for posix-cpu-timers */
+               schedule_timeout(1);
+#endif
+}
+
 /* Set a POSIX.1b interval timer. */
 /* timr->it_lock is taken. */
 static int
@@ -916,6 +933,7 @@ retry:
        if (!timr)
                return -EINVAL;
 
+       rcu_read_lock();
        kc = clockid_to_kclock(timr->it_clock);
        if (WARN_ON_ONCE(!kc || !kc->timer_set))
                error = -EINVAL;
@@ -924,9 +942,12 @@ retry:
 
        unlock_timer(timr, flag);
        if (error == TIMER_RETRY) {
+               timer_wait_for_callback(kc, timr);
                rtn = NULL;     // We already got the old time...
+               rcu_read_unlock();
                goto retry;
        }
+       rcu_read_unlock();
 
        if (old_setting && !error &&
            copy_to_user(old_setting, &old_spec, sizeof (old_spec)))
@@ -964,10 +985,15 @@ retry_delete:
        if (!timer)
                return -EINVAL;
 
+       rcu_read_lock();
        if (timer_delete_hook(timer) == TIMER_RETRY) {
                unlock_timer(timer, flags);
+               timer_wait_for_callback(clockid_to_kclock(timer->it_clock),
+                                       timer);
+               rcu_read_unlock();
                goto retry_delete;
        }
+       rcu_read_unlock();
 
        spin_lock(&current->sighand->siglock);
        list_del(&timer->list);
@@ -993,8 +1019,18 @@ static void itimer_delete(struct k_itimer *timer)
 retry_delete:
        spin_lock_irqsave(&timer->it_lock, flags);
 
+       /* On RT we can race with a deletion */
+       if (!timer->it_signal) {
+               unlock_timer(timer, flags);
+               return;
+       }
+
        if (timer_delete_hook(timer) == TIMER_RETRY) {
+               rcu_read_lock();
                unlock_timer(timer, flags);
+               timer_wait_for_callback(clockid_to_kclock(timer->it_clock),
+                                       timer);
+               rcu_read_unlock();
                goto retry_delete;
        }
        list_del(&timer->list);
index 690b797..fe8ba16 100644 (file)
@@ -107,5 +107,6 @@ void tick_setup_hrtimer_broadcast(void)
 {
        hrtimer_init(&bctimer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
        bctimer.function = bc_handler;
+       bctimer.irqsafe = true;
        clockevents_register_device(&ce_broadcast_hrtimer);
 }
index 4fcd99e..5a47f2e 100644 (file)
@@ -79,13 +79,15 @@ int tick_is_oneshot_available(void)
 static void tick_periodic(int cpu)
 {
        if (tick_do_timer_cpu == cpu) {
-               write_seqlock(&jiffies_lock);
+               raw_spin_lock(&jiffies_lock);
+               write_seqcount_begin(&jiffies_seq);
 
                /* Keep track of the next tick event */
                tick_next_period = ktime_add(tick_next_period, tick_period);
 
                do_timer(1);
-               write_sequnlock(&jiffies_lock);
+               write_seqcount_end(&jiffies_seq);
+               raw_spin_unlock(&jiffies_lock);
                update_wall_time();
        }
 
@@ -157,9 +159,9 @@ void tick_setup_periodic(struct clock_event_device *dev, int broadcast)
                ktime_t next;
 
                do {
-                       seq = read_seqbegin(&jiffies_lock);
+                       seq = read_seqcount_begin(&jiffies_seq);
                        next = tick_next_period;
-               } while (read_seqretry(&jiffies_lock, seq));
+               } while (read_seqcount_retry(&jiffies_seq, seq));
 
                clockevents_switch_state(dev, CLOCK_EVT_STATE_ONESHOT);
 
index 65aafad..c82ddc7 100644 (file)
@@ -62,7 +62,8 @@ static void tick_do_update_jiffies64(ktime_t now)
                return;
 
        /* Reevaluate with jiffies_lock held */
-       write_seqlock(&jiffies_lock);
+       raw_spin_lock(&jiffies_lock);
+       write_seqcount_begin(&jiffies_seq);
 
        delta = ktime_sub(now, last_jiffies_update);
        if (delta.tv64 >= tick_period.tv64) {
@@ -85,10 +86,12 @@ static void tick_do_update_jiffies64(ktime_t now)
                /* Keep the tick_next_period variable up to date */
                tick_next_period = ktime_add(last_jiffies_update, tick_period);
        } else {
-               write_sequnlock(&jiffies_lock);
+               write_seqcount_end(&jiffies_seq);
+               raw_spin_unlock(&jiffies_lock);
                return;
        }
-       write_sequnlock(&jiffies_lock);
+       write_seqcount_end(&jiffies_seq);
+       raw_spin_unlock(&jiffies_lock);
        update_wall_time();
 }
 
@@ -99,12 +102,14 @@ static ktime_t tick_init_jiffy_update(void)
 {
        ktime_t period;
 
-       write_seqlock(&jiffies_lock);
+       raw_spin_lock(&jiffies_lock);
+       write_seqcount_begin(&jiffies_seq);
        /* Did we start the jiffies update yet ? */
        if (last_jiffies_update.tv64 == 0)
                last_jiffies_update = tick_next_period;
        period = last_jiffies_update;
-       write_sequnlock(&jiffies_lock);
+       write_seqcount_end(&jiffies_seq);
+       raw_spin_unlock(&jiffies_lock);
        return period;
 }
 
@@ -215,6 +220,7 @@ static void nohz_full_kick_func(struct irq_work *work)
 
 static DEFINE_PER_CPU(struct irq_work, nohz_full_kick_work) = {
        .func = nohz_full_kick_func,
+       .flags = IRQ_WORK_HARD_IRQ,
 };
 
 /*
@@ -678,10 +684,10 @@ static ktime_t tick_nohz_stop_sched_tick(struct tick_sched *ts,
 
        /* Read jiffies and the time when jiffies were updated last */
        do {
-               seq = read_seqbegin(&jiffies_lock);
+               seq = read_seqcount_begin(&jiffies_seq);
                basemono = last_jiffies_update.tv64;
                basejiff = jiffies;
-       } while (read_seqretry(&jiffies_lock, seq));
+       } while (read_seqcount_retry(&jiffies_seq, seq));
        ts->last_jiffies = basejiff;
 
        /*
@@ -892,14 +898,7 @@ static bool can_stop_idle_tick(int cpu, struct tick_sched *ts)
                return false;
 
        if (unlikely(local_softirq_pending() && cpu_online(cpu))) {
-               static int ratelimit;
-
-               if (ratelimit < 10 &&
-                   (local_softirq_pending() & SOFTIRQ_STOP_IDLE_MASK)) {
-                       pr_warn("NOHZ: local_softirq_pending %02x\n",
-                               (unsigned int) local_softirq_pending());
-                       ratelimit++;
-               }
+               softirq_check_pending_idle();
                return false;
        }
 
@@ -1220,6 +1219,7 @@ void tick_setup_sched_timer(void)
         * Emulate tick processing via per-CPU hrtimers:
         */
        hrtimer_init(&ts->sched_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
+       ts->sched_timer.irqsafe = 1;
        ts->sched_timer.function = tick_sched_timer;
 
        /* Get the next period (per-CPU) */
index f36b524..bca8a74 100644 (file)
@@ -2381,8 +2381,10 @@ EXPORT_SYMBOL(hardpps);
  */
 void xtime_update(unsigned long ticks)
 {
-       write_seqlock(&jiffies_lock);
+       raw_spin_lock(&jiffies_lock);
+       write_seqcount_begin(&jiffies_seq);
        do_timer(ticks);
-       write_sequnlock(&jiffies_lock);
+       write_seqcount_end(&jiffies_seq);
+       raw_spin_unlock(&jiffies_lock);
        update_wall_time();
 }
index 704f595..763a3e5 100644 (file)
@@ -19,7 +19,8 @@ extern void timekeeping_resume(void);
 extern void do_timer(unsigned long ticks);
 extern void update_wall_time(void);
 
-extern seqlock_t jiffies_lock;
+extern raw_spinlock_t jiffies_lock;
+extern seqcount_t jiffies_seq;
 
 #define CS_NAME_LEN    32
 
index d2e4698..db7bf59 100644 (file)
@@ -194,8 +194,11 @@ EXPORT_SYMBOL(jiffies_64);
 #endif
 
 struct timer_base {
-       spinlock_t              lock;
+       raw_spinlock_t          lock;
        struct timer_list       *running_timer;
+#ifdef CONFIG_PREEMPT_RT_FULL
+       struct swait_queue_head wait_for_running_timer;
+#endif
        unsigned long           clk;
        unsigned long           next_expiry;
        unsigned int            cpu;
@@ -954,10 +957,10 @@ static struct timer_base *lock_timer_base(struct timer_list *timer,
 
                if (!(tf & TIMER_MIGRATING)) {
                        base = get_timer_base(tf);
-                       spin_lock_irqsave(&base->lock, *flags);
+                       raw_spin_lock_irqsave(&base->lock, *flags);
                        if (timer->flags == tf)
                                return base;
-                       spin_unlock_irqrestore(&base->lock, *flags);
+                       raw_spin_unlock_irqrestore(&base->lock, *flags);
                }
                cpu_relax();
        }
@@ -1034,9 +1037,9 @@ __mod_timer(struct timer_list *timer, unsigned long expires, bool pending_only)
                        /* See the comment in lock_timer_base() */
                        timer->flags |= TIMER_MIGRATING;
 
-                       spin_unlock(&base->lock);
+                       raw_spin_unlock(&base->lock);
                        base = new_base;
-                       spin_lock(&base->lock);
+                       raw_spin_lock(&base->lock);
                        WRITE_ONCE(timer->flags,
                                   (timer->flags & ~TIMER_BASEMASK) | base->cpu);
                        forward_timer_base(base);
@@ -1061,7 +1064,7 @@ __mod_timer(struct timer_list *timer, unsigned long expires, bool pending_only)
        }
 
 out_unlock:
-       spin_unlock_irqrestore(&base->lock, flags);
+       raw_spin_unlock_irqrestore(&base->lock, flags);
 
        return ret;
 }
@@ -1155,9 +1158,9 @@ void add_timer_on(struct timer_list *timer, int cpu)
        if (base != new_base) {
                timer->flags |= TIMER_MIGRATING;
 
-               spin_unlock(&base->lock);
+               raw_spin_unlock(&base->lock);
                base = new_base;
-               spin_lock(&base->lock);
+               raw_spin_lock(&base->lock);
                WRITE_ONCE(timer->flags,
                           (timer->flags & ~TIMER_BASEMASK) | cpu);
        }
@@ -1165,10 +1168,37 @@ void add_timer_on(struct timer_list *timer, int cpu)
 
        debug_activate(timer, timer->expires);
        internal_add_timer(base, timer);
-       spin_unlock_irqrestore(&base->lock, flags);
+       raw_spin_unlock_irqrestore(&base->lock, flags);
 }
 EXPORT_SYMBOL_GPL(add_timer_on);
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+/*
+ * Wait for a running timer
+ */
+static void wait_for_running_timer(struct timer_list *timer)
+{
+       struct timer_base *base;
+       u32 tf = timer->flags;
+
+       if (tf & TIMER_MIGRATING)
+               return;
+
+       base = get_timer_base(tf);
+       swait_event(base->wait_for_running_timer,
+                  base->running_timer != timer);
+}
+
+# define wakeup_timer_waiters(b)       swake_up_all(&(b)->wait_for_running_timer)
+#else
+static inline void wait_for_running_timer(struct timer_list *timer)
+{
+       cpu_relax();
+}
+
+# define wakeup_timer_waiters(b)       do { } while (0)
+#endif
+
 /**
  * del_timer - deactive a timer.
  * @timer: the timer to be deactivated
@@ -1192,7 +1222,7 @@ int del_timer(struct timer_list *timer)
        if (timer_pending(timer)) {
                base = lock_timer_base(timer, &flags);
                ret = detach_if_pending(timer, base, true);
-               spin_unlock_irqrestore(&base->lock, flags);
+               raw_spin_unlock_irqrestore(&base->lock, flags);
        }
 
        return ret;
@@ -1220,13 +1250,13 @@ int try_to_del_timer_sync(struct timer_list *timer)
                timer_stats_timer_clear_start_info(timer);
                ret = detach_if_pending(timer, base, true);
        }
-       spin_unlock_irqrestore(&base->lock, flags);
+       raw_spin_unlock_irqrestore(&base->lock, flags);
 
        return ret;
 }
 EXPORT_SYMBOL(try_to_del_timer_sync);
 
-#ifdef CONFIG_SMP
+#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT_FULL)
 /**
  * del_timer_sync - deactivate a timer and wait for the handler to finish.
  * @timer: the timer to be deactivated
@@ -1286,7 +1316,7 @@ int del_timer_sync(struct timer_list *timer)
                int ret = try_to_del_timer_sync(timer);
                if (ret >= 0)
                        return ret;
-               cpu_relax();
+               wait_for_running_timer(timer);
        }
 }
 EXPORT_SYMBOL(del_timer_sync);
@@ -1351,14 +1381,17 @@ static void expire_timers(struct timer_base *base, struct hlist_head *head)
                fn = timer->function;
                data = timer->data;
 
-               if (timer->flags & TIMER_IRQSAFE) {
-                       spin_unlock(&base->lock);
+               if (!IS_ENABLED(CONFIG_PREEMPT_RT_FULL) &&
+                   timer->flags & TIMER_IRQSAFE) {
+                       raw_spin_unlock(&base->lock);
                        call_timer_fn(timer, fn, data);
-                       spin_lock(&base->lock);
+                       base->running_timer = NULL;
+                       raw_spin_lock(&base->lock);
                } else {
-                       spin_unlock_irq(&base->lock);
+                       raw_spin_unlock_irq(&base->lock);
                        call_timer_fn(timer, fn, data);
-                       spin_lock_irq(&base->lock);
+                       base->running_timer = NULL;
+                       raw_spin_lock_irq(&base->lock);
                }
        }
 }
@@ -1527,7 +1560,7 @@ u64 get_next_timer_interrupt(unsigned long basej, u64 basem)
        if (cpu_is_offline(smp_processor_id()))
                return expires;
 
-       spin_lock(&base->lock);
+       raw_spin_lock(&base->lock);
        nextevt = __next_timer_interrupt(base);
        is_max_delta = (nextevt == base->clk + NEXT_TIMER_MAX_DELTA);
        base->next_expiry = nextevt;
@@ -1561,7 +1594,7 @@ u64 get_next_timer_interrupt(unsigned long basej, u64 basem)
                        base->is_idle = true;
                }
        }
-       spin_unlock(&base->lock);
+       raw_spin_unlock(&base->lock);
 
        return cmp_next_hrtimer_event(basem, expires);
 }
@@ -1628,13 +1661,13 @@ void update_process_times(int user_tick)
 
        /* Note: this timer irq context must be accounted for as well. */
        account_process_tick(p, user_tick);
+       scheduler_tick();
        run_local_timers();
        rcu_check_callbacks(user_tick);
-#ifdef CONFIG_IRQ_WORK
+#if defined(CONFIG_IRQ_WORK)
        if (in_irq())
                irq_work_tick();
 #endif
-       scheduler_tick();
        run_posix_cpu_timers(p);
 
        /* The current CPU might make use of net randoms without receiving IRQs
@@ -1657,7 +1690,7 @@ static inline void __run_timers(struct timer_base *base)
        if (!time_after_eq(jiffies, base->clk))
                return;
 
-       spin_lock_irq(&base->lock);
+       raw_spin_lock_irq(&base->lock);
 
        /*
         * timer_base::must_forward_clk must be cleared before running
@@ -1683,8 +1716,8 @@ static inline void __run_timers(struct timer_base *base)
                while (levels--)
                        expire_timers(base, heads + levels);
        }
-       base->running_timer = NULL;
-       spin_unlock_irq(&base->lock);
+       raw_spin_unlock_irq(&base->lock);
+       wakeup_timer_waiters(base);
 }
 
 /*
@@ -1694,6 +1727,8 @@ static __latent_entropy void run_timer_softirq(struct softirq_action *h)
 {
        struct timer_base *base = this_cpu_ptr(&timer_bases[BASE_STD]);
 
+       irq_work_tick_soft();
+
        __run_timers(base);
        if (IS_ENABLED(CONFIG_NO_HZ_COMMON))
                __run_timers(this_cpu_ptr(&timer_bases[BASE_DEF]));
@@ -1894,8 +1929,8 @@ int timers_dead_cpu(unsigned int cpu)
                 * The caller is globally serialized and nobody else
                 * takes two locks at once, deadlock is not possible.
                 */
-               spin_lock_irq(&new_base->lock);
-               spin_lock_nested(&old_base->lock, SINGLE_DEPTH_NESTING);
+               raw_spin_lock_irq(&new_base->lock);
+               raw_spin_lock_nested(&old_base->lock, SINGLE_DEPTH_NESTING);
 
                /*
                 * The current CPUs base clock might be stale. Update it
@@ -1908,8 +1943,8 @@ int timers_dead_cpu(unsigned int cpu)
                for (i = 0; i < WHEEL_SIZE; i++)
                        migrate_timer_list(new_base, old_base->vectors + i);
 
-               spin_unlock(&old_base->lock);
-               spin_unlock_irq(&new_base->lock);
+               raw_spin_unlock(&old_base->lock);
+               raw_spin_unlock_irq(&new_base->lock);
                put_cpu_ptr(&timer_bases);
        }
        return 0;
@@ -1925,8 +1960,11 @@ static void __init init_timer_cpu(int cpu)
        for (i = 0; i < NR_BASES; i++) {
                base = per_cpu_ptr(&timer_bases[i], cpu);
                base->cpu = cpu;
-               spin_lock_init(&base->lock);
+               raw_spin_lock_init(&base->lock);
                base->clk = jiffies;
+#ifdef CONFIG_PREEMPT_RT_FULL
+               init_swait_queue_head(&base->wait_for_running_timer);
+#endif
        }
 }
 
index 5771ce7..3e8de30 100644 (file)
@@ -196,6 +196,24 @@ config IRQSOFF_TRACER
          enabled. This option and the preempt-off timing option can be
          used together or separately.)
 
+config INTERRUPT_OFF_HIST
+       bool "Interrupts-off Latency Histogram"
+       depends on IRQSOFF_TRACER
+       help
+         This option generates continuously updated histograms (one per cpu)
+         of the duration of time periods with interrupts disabled. The
+         histograms are disabled by default. To enable them, write a non-zero
+         number to
+
+             /sys/kernel/debug/tracing/latency_hist/enable/preemptirqsoff
+
+         If PREEMPT_OFF_HIST is also selected, additional histograms (one
+         per cpu) are generated that accumulate the duration of time periods
+         when both interrupts and preemption are disabled. The histogram data
+         will be located in the debug file system at
+
+             /sys/kernel/debug/tracing/latency_hist/irqsoff
+
 config PREEMPT_TRACER
        bool "Preemption-off Latency Tracer"
        default n
@@ -220,6 +238,24 @@ config PREEMPT_TRACER
          enabled. This option and the irqs-off timing option can be
          used together or separately.)
 
+config PREEMPT_OFF_HIST
+       bool "Preemption-off Latency Histogram"
+       depends on PREEMPT_TRACER
+       help
+         This option generates continuously updated histograms (one per cpu)
+         of the duration of time periods with preemption disabled. The
+         histograms are disabled by default. To enable them, write a non-zero
+         number to
+
+             /sys/kernel/debug/tracing/latency_hist/enable/preemptirqsoff
+
+         If INTERRUPT_OFF_HIST is also selected, additional histograms (one
+         per cpu) are generated that accumulate the duration of time periods
+         when both interrupts and preemption are disabled. The histogram data
+         will be located in the debug file system at
+
+             /sys/kernel/debug/tracing/latency_hist/preemptoff
+
 config SCHED_TRACER
        bool "Scheduling Latency Tracer"
        select GENERIC_TRACER
@@ -265,6 +301,74 @@ config HWLAT_TRACER
         file. Every time a latency is greater than tracing_thresh, it will
         be recorded into the ring buffer.
 
+config WAKEUP_LATENCY_HIST
+       bool "Scheduling Latency Histogram"
+       depends on SCHED_TRACER
+       help
+         This option generates continuously updated histograms (one per cpu)
+         of the scheduling latency of the highest priority task.
+         The histograms are disabled by default. To enable them, write a
+         non-zero number to
+
+             /sys/kernel/debug/tracing/latency_hist/enable/wakeup
+
+         Two different algorithms are used, one to determine the latency of
+         processes that exclusively use the highest priority of the system and
+         another one to determine the latency of processes that share the
+         highest system priority with other processes. The former is used to
+         improve hardware and system software, the latter to optimize the
+         priority design of a given system. The histogram data will be
+         located in the debug file system at
+
+             /sys/kernel/debug/tracing/latency_hist/wakeup
+
+         and
+
+             /sys/kernel/debug/tracing/latency_hist/wakeup/sharedprio
+
+         If both Scheduling Latency Histogram and Missed Timer Offsets
+         Histogram are selected, additional histogram data will be collected
+         that contain, in addition to the wakeup latency, the timer latency, in
+         case the wakeup was triggered by an expired timer. These histograms
+         are available in the
+
+             /sys/kernel/debug/tracing/latency_hist/timerandwakeup
+
+         directory. They reflect the apparent interrupt and scheduling latency
+         and are best suitable to determine the worst-case latency of a given
+         system. To enable these histograms, write a non-zero number to
+
+             /sys/kernel/debug/tracing/latency_hist/enable/timerandwakeup
+
+config MISSED_TIMER_OFFSETS_HIST
+       depends on HIGH_RES_TIMERS
+       select GENERIC_TRACER
+       bool "Missed Timer Offsets Histogram"
+       help
+         Generate a histogram of missed timer offsets in microseconds. The
+         histograms are disabled by default. To enable them, write a non-zero
+         number to
+
+             /sys/kernel/debug/tracing/latency_hist/enable/missed_timer_offsets
+
+         The histogram data will be located in the debug file system at
+
+             /sys/kernel/debug/tracing/latency_hist/missed_timer_offsets
+
+         If both Scheduling Latency Histogram and Missed Timer Offsets
+         Histogram are selected, additional histogram data will be collected
+         that contain, in addition to the wakeup latency, the timer latency, in
+         case the wakeup was triggered by an expired timer. These histograms
+         are available in the
+
+             /sys/kernel/debug/tracing/latency_hist/timerandwakeup
+
+         directory. They reflect the apparent interrupt and scheduling latency
+         and are best suitable to determine the worst-case latency of a given
+         system. To enable these histograms, write a non-zero number to
+
+             /sys/kernel/debug/tracing/latency_hist/enable/timerandwakeup
+
 config ENABLE_DEFAULT_TRACERS
        bool "Trace process context switches and events"
        depends on !GENERIC_TRACER
index 907c144..77c6a1f 100644 (file)
@@ -39,6 +39,10 @@ obj-$(CONFIG_IRQSOFF_TRACER) += trace_irqsoff.o
 obj-$(CONFIG_PREEMPT_TRACER) += trace_irqsoff.o
 obj-$(CONFIG_SCHED_TRACER) += trace_sched_wakeup.o
 obj-$(CONFIG_HWLAT_TRACER) += trace_hwlat.o
+obj-$(CONFIG_INTERRUPT_OFF_HIST) += latency_hist.o
+obj-$(CONFIG_PREEMPT_OFF_HIST) += latency_hist.o
+obj-$(CONFIG_WAKEUP_LATENCY_HIST) += latency_hist.o
+obj-$(CONFIG_MISSED_TIMER_OFFSETS_HIST) += latency_hist.o
 obj-$(CONFIG_NOP_TRACER) += trace_nop.o
 obj-$(CONFIG_STACK_TRACER) += trace_stack.o
 obj-$(CONFIG_MMIOTRACE) += trace_mmiotrace.o
diff --git a/kernel/trace/latency_hist.c b/kernel/trace/latency_hist.c
new file mode 100644 (file)
index 0000000..7f6ee70
--- /dev/null
@@ -0,0 +1,1178 @@
+/*
+ * kernel/trace/latency_hist.c
+ *
+ * Add support for histograms of preemption-off latency and
+ * interrupt-off latency and wakeup latency, it depends on
+ * Real-Time Preemption Support.
+ *
+ *  Copyright (C) 2005 MontaVista Software, Inc.
+ *  Yi Yang <yyang@ch.mvista.com>
+ *
+ *  Converted to work with the new latency tracer.
+ *  Copyright (C) 2008 Red Hat, Inc.
+ *    Steven Rostedt <srostedt@redhat.com>
+ *
+ */
+#include <linux/module.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+#include <linux/percpu.h>
+#include <linux/kallsyms.h>
+#include <linux/uaccess.h>
+#include <linux/sched.h>
+#include <linux/sched/rt.h>
+#include <linux/slab.h>
+#include <linux/atomic.h>
+#include <asm/div64.h>
+
+#include "trace.h"
+#include <trace/events/sched.h>
+
+#define NSECS_PER_USECS 1000L
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/hist.h>
+
+enum {
+       IRQSOFF_LATENCY = 0,
+       PREEMPTOFF_LATENCY,
+       PREEMPTIRQSOFF_LATENCY,
+       WAKEUP_LATENCY,
+       WAKEUP_LATENCY_SHAREDPRIO,
+       MISSED_TIMER_OFFSETS,
+       TIMERANDWAKEUP_LATENCY,
+       MAX_LATENCY_TYPE,
+};
+
+#define MAX_ENTRY_NUM 10240
+
+struct hist_data {
+       atomic_t hist_mode; /* 0 log, 1 don't log */
+       long offset; /* set it to MAX_ENTRY_NUM/2 for a bipolar scale */
+       long min_lat;
+       long max_lat;
+       unsigned long long below_hist_bound_samples;
+       unsigned long long above_hist_bound_samples;
+       long long accumulate_lat;
+       unsigned long long total_samples;
+       unsigned long long hist_array[MAX_ENTRY_NUM];
+};
+
+struct enable_data {
+       int latency_type;
+       int enabled;
+};
+
+static char *latency_hist_dir_root = "latency_hist";
+
+#ifdef CONFIG_INTERRUPT_OFF_HIST
+static DEFINE_PER_CPU(struct hist_data, irqsoff_hist);
+static char *irqsoff_hist_dir = "irqsoff";
+static DEFINE_PER_CPU(cycles_t, hist_irqsoff_start);
+static DEFINE_PER_CPU(int, hist_irqsoff_counting);
+#endif
+
+#ifdef CONFIG_PREEMPT_OFF_HIST
+static DEFINE_PER_CPU(struct hist_data, preemptoff_hist);
+static char *preemptoff_hist_dir = "preemptoff";
+static DEFINE_PER_CPU(cycles_t, hist_preemptoff_start);
+static DEFINE_PER_CPU(int, hist_preemptoff_counting);
+#endif
+
+#if defined(CONFIG_PREEMPT_OFF_HIST) && defined(CONFIG_INTERRUPT_OFF_HIST)
+static DEFINE_PER_CPU(struct hist_data, preemptirqsoff_hist);
+static char *preemptirqsoff_hist_dir = "preemptirqsoff";
+static DEFINE_PER_CPU(cycles_t, hist_preemptirqsoff_start);
+static DEFINE_PER_CPU(int, hist_preemptirqsoff_counting);
+#endif
+
+#if defined(CONFIG_PREEMPT_OFF_HIST) || defined(CONFIG_INTERRUPT_OFF_HIST)
+static notrace void probe_preemptirqsoff_hist(void *v, int reason, int start);
+static struct enable_data preemptirqsoff_enabled_data = {
+       .latency_type = PREEMPTIRQSOFF_LATENCY,
+       .enabled = 0,
+};
+#endif
+
+#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
+       defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
+struct maxlatproc_data {
+       char comm[FIELD_SIZEOF(struct task_struct, comm)];
+       char current_comm[FIELD_SIZEOF(struct task_struct, comm)];
+       int pid;
+       int current_pid;
+       int prio;
+       int current_prio;
+       long latency;
+       long timeroffset;
+       cycle_t timestamp;
+};
+#endif
+
+#ifdef CONFIG_WAKEUP_LATENCY_HIST
+static DEFINE_PER_CPU(struct hist_data, wakeup_latency_hist);
+static DEFINE_PER_CPU(struct hist_data, wakeup_latency_hist_sharedprio);
+static char *wakeup_latency_hist_dir = "wakeup";
+static char *wakeup_latency_hist_dir_sharedprio = "sharedprio";
+static notrace void probe_wakeup_latency_hist_start(void *v,
+       struct task_struct *p);
+static notrace void probe_wakeup_latency_hist_stop(void *v,
+       bool preempt, struct task_struct *prev, struct task_struct *next);
+static notrace void probe_sched_migrate_task(void *,
+       struct task_struct *task, int cpu);
+static struct enable_data wakeup_latency_enabled_data = {
+       .latency_type = WAKEUP_LATENCY,
+       .enabled = 0,
+};
+static DEFINE_PER_CPU(struct maxlatproc_data, wakeup_maxlatproc);
+static DEFINE_PER_CPU(struct maxlatproc_data, wakeup_maxlatproc_sharedprio);
+static DEFINE_PER_CPU(struct task_struct *, wakeup_task);
+static DEFINE_PER_CPU(int, wakeup_sharedprio);
+static unsigned long wakeup_pid;
+#endif
+
+#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
+static DEFINE_PER_CPU(struct hist_data, missed_timer_offsets);
+static char *missed_timer_offsets_dir = "missed_timer_offsets";
+static notrace void probe_hrtimer_interrupt(void *v, int cpu,
+       long long offset, struct task_struct *curr, struct task_struct *task);
+static struct enable_data missed_timer_offsets_enabled_data = {
+       .latency_type = MISSED_TIMER_OFFSETS,
+       .enabled = 0,
+};
+static DEFINE_PER_CPU(struct maxlatproc_data, missed_timer_offsets_maxlatproc);
+static unsigned long missed_timer_offsets_pid;
+#endif
+
+#if defined(CONFIG_WAKEUP_LATENCY_HIST) && \
+       defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
+static DEFINE_PER_CPU(struct hist_data, timerandwakeup_latency_hist);
+static char *timerandwakeup_latency_hist_dir = "timerandwakeup";
+static struct enable_data timerandwakeup_enabled_data = {
+       .latency_type = TIMERANDWAKEUP_LATENCY,
+       .enabled = 0,
+};
+static DEFINE_PER_CPU(struct maxlatproc_data, timerandwakeup_maxlatproc);
+#endif
+
+void notrace latency_hist(int latency_type, int cpu, long latency,
+                         long timeroffset, cycle_t stop,
+                         struct task_struct *p)
+{
+       struct hist_data *my_hist;
+#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
+       defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
+       struct maxlatproc_data *mp = NULL;
+#endif
+
+       if (!cpu_possible(cpu) || latency_type < 0 ||
+           latency_type >= MAX_LATENCY_TYPE)
+               return;
+
+       switch (latency_type) {
+#ifdef CONFIG_INTERRUPT_OFF_HIST
+       case IRQSOFF_LATENCY:
+               my_hist = &per_cpu(irqsoff_hist, cpu);
+               break;
+#endif
+#ifdef CONFIG_PREEMPT_OFF_HIST
+       case PREEMPTOFF_LATENCY:
+               my_hist = &per_cpu(preemptoff_hist, cpu);
+               break;
+#endif
+#if defined(CONFIG_PREEMPT_OFF_HIST) && defined(CONFIG_INTERRUPT_OFF_HIST)
+       case PREEMPTIRQSOFF_LATENCY:
+               my_hist = &per_cpu(preemptirqsoff_hist, cpu);
+               break;
+#endif
+#ifdef CONFIG_WAKEUP_LATENCY_HIST
+       case WAKEUP_LATENCY:
+               my_hist = &per_cpu(wakeup_latency_hist, cpu);
+               mp = &per_cpu(wakeup_maxlatproc, cpu);
+               break;
+       case WAKEUP_LATENCY_SHAREDPRIO:
+               my_hist = &per_cpu(wakeup_latency_hist_sharedprio, cpu);
+               mp = &per_cpu(wakeup_maxlatproc_sharedprio, cpu);
+               break;
+#endif
+#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
+       case MISSED_TIMER_OFFSETS:
+               my_hist = &per_cpu(missed_timer_offsets, cpu);
+               mp = &per_cpu(missed_timer_offsets_maxlatproc, cpu);
+               break;
+#endif
+#if defined(CONFIG_WAKEUP_LATENCY_HIST) && \
+       defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
+       case TIMERANDWAKEUP_LATENCY:
+               my_hist = &per_cpu(timerandwakeup_latency_hist, cpu);
+               mp = &per_cpu(timerandwakeup_maxlatproc, cpu);
+               break;
+#endif
+
+       default:
+               return;
+       }
+
+       latency += my_hist->offset;
+
+       if (atomic_read(&my_hist->hist_mode) == 0)
+               return;
+
+       if (latency < 0 || latency >= MAX_ENTRY_NUM) {
+               if (latency < 0)
+                       my_hist->below_hist_bound_samples++;
+               else
+                       my_hist->above_hist_bound_samples++;
+       } else
+               my_hist->hist_array[latency]++;
+
+       if (unlikely(latency > my_hist->max_lat ||
+           my_hist->min_lat == LONG_MAX)) {
+#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
+       defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
+               if (latency_type == WAKEUP_LATENCY ||
+                   latency_type == WAKEUP_LATENCY_SHAREDPRIO ||
+                   latency_type == MISSED_TIMER_OFFSETS ||
+                   latency_type == TIMERANDWAKEUP_LATENCY) {
+                       strncpy(mp->comm, p->comm, sizeof(mp->comm));
+                       strncpy(mp->current_comm, current->comm,
+                           sizeof(mp->current_comm));
+                       mp->pid = task_pid_nr(p);
+                       mp->current_pid = task_pid_nr(current);
+                       mp->prio = p->prio;
+                       mp->current_prio = current->prio;
+                       mp->latency = latency;
+                       mp->timeroffset = timeroffset;
+                       mp->timestamp = stop;
+               }
+#endif
+               my_hist->max_lat = latency;
+       }
+       if (unlikely(latency < my_hist->min_lat))
+               my_hist->min_lat = latency;
+       my_hist->total_samples++;
+       my_hist->accumulate_lat += latency;
+}
+
+static void *l_start(struct seq_file *m, loff_t *pos)
+{
+       loff_t *index_ptr = NULL;
+       loff_t index = *pos;
+       struct hist_data *my_hist = m->private;
+
+       if (index == 0) {
+               char minstr[32], avgstr[32], maxstr[32];
+
+               atomic_dec(&my_hist->hist_mode);
+
+               if (likely(my_hist->total_samples)) {
+                       long avg = (long) div64_s64(my_hist->accumulate_lat,
+                           my_hist->total_samples);
+                       snprintf(minstr, sizeof(minstr), "%ld",
+                           my_hist->min_lat - my_hist->offset);
+                       snprintf(avgstr, sizeof(avgstr), "%ld",
+                           avg - my_hist->offset);
+                       snprintf(maxstr, sizeof(maxstr), "%ld",
+                           my_hist->max_lat - my_hist->offset);
+               } else {
+                       strcpy(minstr, "<undef>");
+                       strcpy(avgstr, minstr);
+                       strcpy(maxstr, minstr);
+               }
+
+               seq_printf(m, "#Minimum latency: %s microseconds\n"
+                          "#Average latency: %s microseconds\n"
+                          "#Maximum latency: %s microseconds\n"
+                          "#Total samples: %llu\n"
+                          "#There are %llu samples lower than %ld"
+                          " microseconds.\n"
+                          "#There are %llu samples greater or equal"
+                          " than %ld microseconds.\n"
+                          "#usecs\t%16s\n",
+                          minstr, avgstr, maxstr,
+                          my_hist->total_samples,
+                          my_hist->below_hist_bound_samples,
+                          -my_hist->offset,
+                          my_hist->above_hist_bound_samples,
+                          MAX_ENTRY_NUM - my_hist->offset,
+                          "samples");
+       }
+       if (index < MAX_ENTRY_NUM) {
+               index_ptr = kmalloc(sizeof(loff_t), GFP_KERNEL);
+               if (index_ptr)
+                       *index_ptr = index;
+       }
+
+       return index_ptr;
+}
+
+static void *l_next(struct seq_file *m, void *p, loff_t *pos)
+{
+       loff_t *index_ptr = p;
+       struct hist_data *my_hist = m->private;
+
+       if (++*pos >= MAX_ENTRY_NUM) {
+               atomic_inc(&my_hist->hist_mode);
+               return NULL;
+       }
+       *index_ptr = *pos;
+       return index_ptr;
+}
+
+static void l_stop(struct seq_file *m, void *p)
+{
+       kfree(p);
+}
+
+static int l_show(struct seq_file *m, void *p)
+{
+       int index = *(loff_t *) p;
+       struct hist_data *my_hist = m->private;
+
+       seq_printf(m, "%6ld\t%16llu\n", index - my_hist->offset,
+           my_hist->hist_array[index]);
+       return 0;
+}
+
+static const struct seq_operations latency_hist_seq_op = {
+       .start = l_start,
+       .next  = l_next,
+       .stop  = l_stop,
+       .show  = l_show
+};
+
+static int latency_hist_open(struct inode *inode, struct file *file)
+{
+       int ret;
+
+       ret = seq_open(file, &latency_hist_seq_op);
+       if (!ret) {
+               struct seq_file *seq = file->private_data;
+               seq->private = inode->i_private;
+       }
+       return ret;
+}
+
+static const struct file_operations latency_hist_fops = {
+       .open = latency_hist_open,
+       .read = seq_read,
+       .llseek = seq_lseek,
+       .release = seq_release,
+};
+
+#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
+       defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
+static void clear_maxlatprocdata(struct maxlatproc_data *mp)
+{
+       mp->comm[0] = mp->current_comm[0] = '\0';
+       mp->prio = mp->current_prio = mp->pid = mp->current_pid =
+           mp->latency = mp->timeroffset = -1;
+       mp->timestamp = 0;
+}
+#endif
+
+static void hist_reset(struct hist_data *hist)
+{
+       atomic_dec(&hist->hist_mode);
+
+       memset(hist->hist_array, 0, sizeof(hist->hist_array));
+       hist->below_hist_bound_samples = 0ULL;
+       hist->above_hist_bound_samples = 0ULL;
+       hist->min_lat = LONG_MAX;
+       hist->max_lat = LONG_MIN;
+       hist->total_samples = 0ULL;
+       hist->accumulate_lat = 0LL;
+
+       atomic_inc(&hist->hist_mode);
+}
+
+static ssize_t
+latency_hist_reset(struct file *file, const char __user *a,
+                  size_t size, loff_t *off)
+{
+       int cpu;
+       struct hist_data *hist = NULL;
+#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
+       defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
+       struct maxlatproc_data *mp = NULL;
+#endif
+       off_t latency_type = (off_t) file->private_data;
+
+       for_each_online_cpu(cpu) {
+
+               switch (latency_type) {
+#ifdef CONFIG_PREEMPT_OFF_HIST
+               case PREEMPTOFF_LATENCY:
+                       hist = &per_cpu(preemptoff_hist, cpu);
+                       break;
+#endif
+#ifdef CONFIG_INTERRUPT_OFF_HIST
+               case IRQSOFF_LATENCY:
+                       hist = &per_cpu(irqsoff_hist, cpu);
+                       break;
+#endif
+#if defined(CONFIG_INTERRUPT_OFF_HIST) && defined(CONFIG_PREEMPT_OFF_HIST)
+               case PREEMPTIRQSOFF_LATENCY:
+                       hist = &per_cpu(preemptirqsoff_hist, cpu);
+                       break;
+#endif
+#ifdef CONFIG_WAKEUP_LATENCY_HIST
+               case WAKEUP_LATENCY:
+                       hist = &per_cpu(wakeup_latency_hist, cpu);
+                       mp = &per_cpu(wakeup_maxlatproc, cpu);
+                       break;
+               case WAKEUP_LATENCY_SHAREDPRIO:
+                       hist = &per_cpu(wakeup_latency_hist_sharedprio, cpu);
+                       mp = &per_cpu(wakeup_maxlatproc_sharedprio, cpu);
+                       break;
+#endif
+#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
+               case MISSED_TIMER_OFFSETS:
+                       hist = &per_cpu(missed_timer_offsets, cpu);
+                       mp = &per_cpu(missed_timer_offsets_maxlatproc, cpu);
+                       break;
+#endif
+#if defined(CONFIG_WAKEUP_LATENCY_HIST) && \
+       defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
+               case TIMERANDWAKEUP_LATENCY:
+                       hist = &per_cpu(timerandwakeup_latency_hist, cpu);
+                       mp = &per_cpu(timerandwakeup_maxlatproc, cpu);
+                       break;
+#endif
+               }
+
+               hist_reset(hist);
+#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
+       defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
+               if (latency_type == WAKEUP_LATENCY ||
+                   latency_type == WAKEUP_LATENCY_SHAREDPRIO ||
+                   latency_type == MISSED_TIMER_OFFSETS ||
+                   latency_type == TIMERANDWAKEUP_LATENCY)
+                       clear_maxlatprocdata(mp);
+#endif
+       }
+
+       return size;
+}
+
+#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
+       defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
+static ssize_t
+show_pid(struct file *file, char __user *ubuf, size_t cnt, loff_t *ppos)
+{
+       char buf[64];
+       int r;
+       unsigned long *this_pid = file->private_data;
+
+       r = snprintf(buf, sizeof(buf), "%lu\n", *this_pid);
+       return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+}
+
+static ssize_t do_pid(struct file *file, const char __user *ubuf,
+                     size_t cnt, loff_t *ppos)
+{
+       char buf[64];
+       unsigned long pid;
+       unsigned long *this_pid = file->private_data;
+
+       if (cnt >= sizeof(buf))
+               return -EINVAL;
+
+       if (copy_from_user(&buf, ubuf, cnt))
+               return -EFAULT;
+
+       buf[cnt] = '\0';
+
+       if (kstrtoul(buf, 10, &pid))
+               return -EINVAL;
+
+       *this_pid = pid;
+
+       return cnt;
+}
+#endif
+
+#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
+       defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
+static ssize_t
+show_maxlatproc(struct file *file, char __user *ubuf, size_t cnt, loff_t *ppos)
+{
+       int r;
+       struct maxlatproc_data *mp = file->private_data;
+       int strmaxlen = (TASK_COMM_LEN * 2) + (8 * 8);
+       unsigned long long t;
+       unsigned long usecs, secs;
+       char *buf;
+
+       if (mp->pid == -1 || mp->current_pid == -1) {
+               buf = "(none)\n";
+               return simple_read_from_buffer(ubuf, cnt, ppos, buf,
+                   strlen(buf));
+       }
+
+       buf = kmalloc(strmaxlen, GFP_KERNEL);
+       if (buf == NULL)
+               return -ENOMEM;
+
+       t = ns2usecs(mp->timestamp);
+       usecs = do_div(t, USEC_PER_SEC);
+       secs = (unsigned long) t;
+       r = snprintf(buf, strmaxlen,
+           "%d %d %ld (%ld) %s <- %d %d %s %lu.%06lu\n", mp->pid,
+           MAX_RT_PRIO-1 - mp->prio, mp->latency, mp->timeroffset, mp->comm,
+           mp->current_pid, MAX_RT_PRIO-1 - mp->current_prio, mp->current_comm,
+           secs, usecs);
+       r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+       kfree(buf);
+       return r;
+}
+#endif
+
+static ssize_t
+show_enable(struct file *file, char __user *ubuf, size_t cnt, loff_t *ppos)
+{
+       char buf[64];
+       struct enable_data *ed = file->private_data;
+       int r;
+
+       r = snprintf(buf, sizeof(buf), "%d\n", ed->enabled);
+       return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+}
+
+static ssize_t
+do_enable(struct file *file, const char __user *ubuf, size_t cnt, loff_t *ppos)
+{
+       char buf[64];
+       long enable;
+       struct enable_data *ed = file->private_data;
+
+       if (cnt >= sizeof(buf))
+               return -EINVAL;
+
+       if (copy_from_user(&buf, ubuf, cnt))
+               return -EFAULT;
+
+       buf[cnt] = 0;
+
+       if (kstrtoul(buf, 10, &enable))
+               return -EINVAL;
+
+       if ((enable && ed->enabled) || (!enable && !ed->enabled))
+               return cnt;
+
+       if (enable) {
+               int ret;
+
+               switch (ed->latency_type) {
+#if defined(CONFIG_INTERRUPT_OFF_HIST) || defined(CONFIG_PREEMPT_OFF_HIST)
+               case PREEMPTIRQSOFF_LATENCY:
+                       ret = register_trace_preemptirqsoff_hist(
+                           probe_preemptirqsoff_hist, NULL);
+                       if (ret) {
+                               pr_info("wakeup trace: Couldn't assign "
+                                   "probe_preemptirqsoff_hist "
+                                   "to trace_preemptirqsoff_hist\n");
+                               return ret;
+                       }
+                       break;
+#endif
+#ifdef CONFIG_WAKEUP_LATENCY_HIST
+               case WAKEUP_LATENCY:
+                       ret = register_trace_sched_wakeup(
+                           probe_wakeup_latency_hist_start, NULL);
+                       if (ret) {
+                               pr_info("wakeup trace: Couldn't assign "
+                                   "probe_wakeup_latency_hist_start "
+                                   "to trace_sched_wakeup\n");
+                               return ret;
+                       }
+                       ret = register_trace_sched_wakeup_new(
+                           probe_wakeup_latency_hist_start, NULL);
+                       if (ret) {
+                               pr_info("wakeup trace: Couldn't assign "
+                                   "probe_wakeup_latency_hist_start "
+                                   "to trace_sched_wakeup_new\n");
+                               unregister_trace_sched_wakeup(
+                                   probe_wakeup_latency_hist_start, NULL);
+                               return ret;
+                       }
+                       ret = register_trace_sched_switch(
+                           probe_wakeup_latency_hist_stop, NULL);
+                       if (ret) {
+                               pr_info("wakeup trace: Couldn't assign "
+                                   "probe_wakeup_latency_hist_stop "
+                                   "to trace_sched_switch\n");
+                               unregister_trace_sched_wakeup(
+                                   probe_wakeup_latency_hist_start, NULL);
+                               unregister_trace_sched_wakeup_new(
+                                   probe_wakeup_latency_hist_start, NULL);
+                               return ret;
+                       }
+                       ret = register_trace_sched_migrate_task(
+                           probe_sched_migrate_task, NULL);
+                       if (ret) {
+                               pr_info("wakeup trace: Couldn't assign "
+                                   "probe_sched_migrate_task "
+                                   "to trace_sched_migrate_task\n");
+                               unregister_trace_sched_wakeup(
+                                   probe_wakeup_latency_hist_start, NULL);
+                               unregister_trace_sched_wakeup_new(
+                                   probe_wakeup_latency_hist_start, NULL);
+                               unregister_trace_sched_switch(
+                                   probe_wakeup_latency_hist_stop, NULL);
+                               return ret;
+                       }
+                       break;
+#endif
+#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
+               case MISSED_TIMER_OFFSETS:
+                       ret = register_trace_hrtimer_interrupt(
+                           probe_hrtimer_interrupt, NULL);
+                       if (ret) {
+                               pr_info("wakeup trace: Couldn't assign "
+                                   "probe_hrtimer_interrupt "
+                                   "to trace_hrtimer_interrupt\n");
+                               return ret;
+                       }
+                       break;
+#endif
+#if defined(CONFIG_WAKEUP_LATENCY_HIST) && \
+       defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
+               case TIMERANDWAKEUP_LATENCY:
+                       if (!wakeup_latency_enabled_data.enabled ||
+                           !missed_timer_offsets_enabled_data.enabled)
+                               return -EINVAL;
+                       break;
+#endif
+               default:
+                       break;
+               }
+       } else {
+               switch (ed->latency_type) {
+#if defined(CONFIG_INTERRUPT_OFF_HIST) || defined(CONFIG_PREEMPT_OFF_HIST)
+               case PREEMPTIRQSOFF_LATENCY:
+                       {
+                               int cpu;
+
+                               unregister_trace_preemptirqsoff_hist(
+                                   probe_preemptirqsoff_hist, NULL);
+                               for_each_online_cpu(cpu) {
+#ifdef CONFIG_INTERRUPT_OFF_HIST
+                                       per_cpu(hist_irqsoff_counting,
+                                           cpu) = 0;
+#endif
+#ifdef CONFIG_PREEMPT_OFF_HIST
+                                       per_cpu(hist_preemptoff_counting,
+                                           cpu) = 0;
+#endif
+#if defined(CONFIG_INTERRUPT_OFF_HIST) && defined(CONFIG_PREEMPT_OFF_HIST)
+                                       per_cpu(hist_preemptirqsoff_counting,
+                                           cpu) = 0;
+#endif
+                               }
+                       }
+                       break;
+#endif
+#ifdef CONFIG_WAKEUP_LATENCY_HIST
+               case WAKEUP_LATENCY:
+                       {
+                               int cpu;
+
+                               unregister_trace_sched_wakeup(
+                                   probe_wakeup_latency_hist_start, NULL);
+                               unregister_trace_sched_wakeup_new(
+                                   probe_wakeup_latency_hist_start, NULL);
+                               unregister_trace_sched_switch(
+                                   probe_wakeup_latency_hist_stop, NULL);
+                               unregister_trace_sched_migrate_task(
+                                   probe_sched_migrate_task, NULL);
+
+                               for_each_online_cpu(cpu) {
+                                       per_cpu(wakeup_task, cpu) = NULL;
+                                       per_cpu(wakeup_sharedprio, cpu) = 0;
+                               }
+                       }
+#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
+                       timerandwakeup_enabled_data.enabled = 0;
+#endif
+                       break;
+#endif
+#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
+               case MISSED_TIMER_OFFSETS:
+                       unregister_trace_hrtimer_interrupt(
+                           probe_hrtimer_interrupt, NULL);
+#ifdef CONFIG_WAKEUP_LATENCY_HIST
+                       timerandwakeup_enabled_data.enabled = 0;
+#endif
+                       break;
+#endif
+               default:
+                       break;
+               }
+       }
+       ed->enabled = enable;
+       return cnt;
+}
+
+static const struct file_operations latency_hist_reset_fops = {
+       .open = tracing_open_generic,
+       .write = latency_hist_reset,
+};
+
+static const struct file_operations enable_fops = {
+       .open = tracing_open_generic,
+       .read = show_enable,
+       .write = do_enable,
+};
+
+#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
+       defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
+static const struct file_operations pid_fops = {
+       .open = tracing_open_generic,
+       .read = show_pid,
+       .write = do_pid,
+};
+
+static const struct file_operations maxlatproc_fops = {
+       .open = tracing_open_generic,
+       .read = show_maxlatproc,
+};
+#endif
+
+#if defined(CONFIG_INTERRUPT_OFF_HIST) || defined(CONFIG_PREEMPT_OFF_HIST)
+static notrace void probe_preemptirqsoff_hist(void *v, int reason,
+       int starthist)
+{
+       int cpu = raw_smp_processor_id();
+       int time_set = 0;
+
+       if (starthist) {
+               cycle_t uninitialized_var(start);
+
+               if (!preempt_count() && !irqs_disabled())
+                       return;
+
+#ifdef CONFIG_INTERRUPT_OFF_HIST
+               if ((reason == IRQS_OFF || reason == TRACE_START) &&
+                   !per_cpu(hist_irqsoff_counting, cpu)) {
+                       per_cpu(hist_irqsoff_counting, cpu) = 1;
+                       start = ftrace_now(cpu);
+                       time_set++;
+                       per_cpu(hist_irqsoff_start, cpu) = start;
+               }
+#endif
+
+#ifdef CONFIG_PREEMPT_OFF_HIST
+               if ((reason == PREEMPT_OFF || reason == TRACE_START) &&
+                   !per_cpu(hist_preemptoff_counting, cpu)) {
+                       per_cpu(hist_preemptoff_counting, cpu) = 1;
+                       if (!(time_set++))
+                               start = ftrace_now(cpu);
+                       per_cpu(hist_preemptoff_start, cpu) = start;
+               }
+#endif
+
+#if defined(CONFIG_INTERRUPT_OFF_HIST) && defined(CONFIG_PREEMPT_OFF_HIST)
+               if (per_cpu(hist_irqsoff_counting, cpu) &&
+                   per_cpu(hist_preemptoff_counting, cpu) &&
+                   !per_cpu(hist_preemptirqsoff_counting, cpu)) {
+                       per_cpu(hist_preemptirqsoff_counting, cpu) = 1;
+                       if (!time_set)
+                               start = ftrace_now(cpu);
+                       per_cpu(hist_preemptirqsoff_start, cpu) = start;
+               }
+#endif
+       } else {
+               cycle_t uninitialized_var(stop);
+
+#ifdef CONFIG_INTERRUPT_OFF_HIST
+               if ((reason == IRQS_ON || reason == TRACE_STOP) &&
+                   per_cpu(hist_irqsoff_counting, cpu)) {
+                       cycle_t start = per_cpu(hist_irqsoff_start, cpu);
+
+                       stop = ftrace_now(cpu);
+                       time_set++;
+                       if (start) {
+                               long latency = ((long) (stop - start)) /
+                                   NSECS_PER_USECS;
+
+                               latency_hist(IRQSOFF_LATENCY, cpu, latency, 0,
+                                   stop, NULL);
+                       }
+                       per_cpu(hist_irqsoff_counting, cpu) = 0;
+               }
+#endif
+
+#ifdef CONFIG_PREEMPT_OFF_HIST
+               if ((reason == PREEMPT_ON || reason == TRACE_STOP) &&
+                   per_cpu(hist_preemptoff_counting, cpu)) {
+                       cycle_t start = per_cpu(hist_preemptoff_start, cpu);
+
+                       if (!(time_set++))
+                               stop = ftrace_now(cpu);
+                       if (start) {
+                               long latency = ((long) (stop - start)) /
+                                   NSECS_PER_USECS;
+
+                               latency_hist(PREEMPTOFF_LATENCY, cpu, latency,
+                                   0, stop, NULL);
+                       }
+                       per_cpu(hist_preemptoff_counting, cpu) = 0;
+               }
+#endif
+
+#if defined(CONFIG_INTERRUPT_OFF_HIST) && defined(CONFIG_PREEMPT_OFF_HIST)
+               if ((!per_cpu(hist_irqsoff_counting, cpu) ||
+                    !per_cpu(hist_preemptoff_counting, cpu)) &&
+                  per_cpu(hist_preemptirqsoff_counting, cpu)) {
+                       cycle_t start = per_cpu(hist_preemptirqsoff_start, cpu);
+
+                       if (!time_set)
+                               stop = ftrace_now(cpu);
+                       if (start) {
+                               long latency = ((long) (stop - start)) /
+                                   NSECS_PER_USECS;
+
+                               latency_hist(PREEMPTIRQSOFF_LATENCY, cpu,
+                                   latency, 0, stop, NULL);
+                       }
+                       per_cpu(hist_preemptirqsoff_counting, cpu) = 0;
+               }
+#endif
+       }
+}
+#endif
+
+#ifdef CONFIG_WAKEUP_LATENCY_HIST
+static DEFINE_RAW_SPINLOCK(wakeup_lock);
+static notrace void probe_sched_migrate_task(void *v, struct task_struct *task,
+       int cpu)
+{
+       int old_cpu = task_cpu(task);
+
+       if (cpu != old_cpu) {
+               unsigned long flags;
+               struct task_struct *cpu_wakeup_task;
+
+               raw_spin_lock_irqsave(&wakeup_lock, flags);
+
+               cpu_wakeup_task = per_cpu(wakeup_task, old_cpu);
+               if (task == cpu_wakeup_task) {
+                       put_task_struct(cpu_wakeup_task);
+                       per_cpu(wakeup_task, old_cpu) = NULL;
+                       cpu_wakeup_task = per_cpu(wakeup_task, cpu) = task;
+                       get_task_struct(cpu_wakeup_task);
+               }
+
+               raw_spin_unlock_irqrestore(&wakeup_lock, flags);
+       }
+}
+
+static notrace void probe_wakeup_latency_hist_start(void *v,
+       struct task_struct *p)
+{
+       unsigned long flags;
+       struct task_struct *curr = current;
+       int cpu = task_cpu(p);
+       struct task_struct *cpu_wakeup_task;
+
+       raw_spin_lock_irqsave(&wakeup_lock, flags);
+
+       cpu_wakeup_task = per_cpu(wakeup_task, cpu);
+
+       if (wakeup_pid) {
+               if ((cpu_wakeup_task && p->prio == cpu_wakeup_task->prio) ||
+                   p->prio == curr->prio)
+                       per_cpu(wakeup_sharedprio, cpu) = 1;
+               if (likely(wakeup_pid != task_pid_nr(p)))
+                       goto out;
+       } else {
+               if (likely(!rt_task(p)) ||
+                   (cpu_wakeup_task && p->prio > cpu_wakeup_task->prio) ||
+                   p->prio > curr->prio)
+                       goto out;
+               if ((cpu_wakeup_task && p->prio == cpu_wakeup_task->prio) ||
+                   p->prio == curr->prio)
+                       per_cpu(wakeup_sharedprio, cpu) = 1;
+       }
+
+       if (cpu_wakeup_task)
+               put_task_struct(cpu_wakeup_task);
+       cpu_wakeup_task = per_cpu(wakeup_task, cpu) = p;
+       get_task_struct(cpu_wakeup_task);
+       cpu_wakeup_task->preempt_timestamp_hist =
+               ftrace_now(raw_smp_processor_id());
+out:
+       raw_spin_unlock_irqrestore(&wakeup_lock, flags);
+}
+
+static notrace void probe_wakeup_latency_hist_stop(void *v,
+       bool preempt, struct task_struct *prev, struct task_struct *next)
+{
+       unsigned long flags;
+       int cpu = task_cpu(next);
+       long latency;
+       cycle_t stop;
+       struct task_struct *cpu_wakeup_task;
+
+       raw_spin_lock_irqsave(&wakeup_lock, flags);
+
+       cpu_wakeup_task = per_cpu(wakeup_task, cpu);
+
+       if (cpu_wakeup_task == NULL)
+               goto out;
+
+       /* Already running? */
+       if (unlikely(current == cpu_wakeup_task))
+               goto out_reset;
+
+       if (next != cpu_wakeup_task) {
+               if (next->prio < cpu_wakeup_task->prio)
+                       goto out_reset;
+
+               if (next->prio == cpu_wakeup_task->prio)
+                       per_cpu(wakeup_sharedprio, cpu) = 1;
+
+               goto out;
+       }
+
+       if (current->prio == cpu_wakeup_task->prio)
+               per_cpu(wakeup_sharedprio, cpu) = 1;
+
+       /*
+        * The task we are waiting for is about to be switched to.
+        * Calculate latency and store it in histogram.
+        */
+       stop = ftrace_now(raw_smp_processor_id());
+
+       latency = ((long) (stop - next->preempt_timestamp_hist)) /
+           NSECS_PER_USECS;
+
+       if (per_cpu(wakeup_sharedprio, cpu)) {
+               latency_hist(WAKEUP_LATENCY_SHAREDPRIO, cpu, latency, 0, stop,
+                   next);
+               per_cpu(wakeup_sharedprio, cpu) = 0;
+       } else {
+               latency_hist(WAKEUP_LATENCY, cpu, latency, 0, stop, next);
+#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
+               if (timerandwakeup_enabled_data.enabled) {
+                       latency_hist(TIMERANDWAKEUP_LATENCY, cpu,
+                           next->timer_offset + latency, next->timer_offset,
+                           stop, next);
+               }
+#endif
+       }
+
+out_reset:
+#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
+       next->timer_offset = 0;
+#endif
+       put_task_struct(cpu_wakeup_task);
+       per_cpu(wakeup_task, cpu) = NULL;
+out:
+       raw_spin_unlock_irqrestore(&wakeup_lock, flags);
+}
+#endif
+
+#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
+static notrace void probe_hrtimer_interrupt(void *v, int cpu,
+       long long latency_ns, struct task_struct *curr,
+       struct task_struct *task)
+{
+       if (latency_ns <= 0 && task != NULL && rt_task(task) &&
+           (task->prio < curr->prio ||
+           (task->prio == curr->prio &&
+           !cpumask_test_cpu(cpu, &task->cpus_allowed)))) {
+               long latency;
+               cycle_t now;
+
+               if (missed_timer_offsets_pid) {
+                       if (likely(missed_timer_offsets_pid !=
+                           task_pid_nr(task)))
+                               return;
+               }
+
+               now = ftrace_now(cpu);
+               latency = (long) div_s64(-latency_ns, NSECS_PER_USECS);
+               latency_hist(MISSED_TIMER_OFFSETS, cpu, latency, latency, now,
+                   task);
+#ifdef CONFIG_WAKEUP_LATENCY_HIST
+               task->timer_offset = latency;
+#endif
+       }
+}
+#endif
+
+static __init int latency_hist_init(void)
+{
+       struct dentry *latency_hist_root = NULL;
+       struct dentry *dentry;
+#ifdef CONFIG_WAKEUP_LATENCY_HIST
+       struct dentry *dentry_sharedprio;
+#endif
+       struct dentry *entry;
+       struct dentry *enable_root;
+       int i = 0;
+       struct hist_data *my_hist;
+       char name[64];
+       char *cpufmt = "CPU%d";
+#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \
+       defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
+       char *cpufmt_maxlatproc = "max_latency-CPU%d";
+       struct maxlatproc_data *mp = NULL;
+#endif
+
+       dentry = tracing_init_dentry();
+       latency_hist_root = debugfs_create_dir(latency_hist_dir_root, dentry);
+       enable_root = debugfs_create_dir("enable", latency_hist_root);
+
+#ifdef CONFIG_INTERRUPT_OFF_HIST
+       dentry = debugfs_create_dir(irqsoff_hist_dir, latency_hist_root);
+       for_each_possible_cpu(i) {
+               sprintf(name, cpufmt, i);
+               entry = debugfs_create_file(name, 0444, dentry,
+                   &per_cpu(irqsoff_hist, i), &latency_hist_fops);
+               my_hist = &per_cpu(irqsoff_hist, i);
+               atomic_set(&my_hist->hist_mode, 1);
+               my_hist->min_lat = LONG_MAX;
+       }
+       entry = debugfs_create_file("reset", 0644, dentry,
+           (void *)IRQSOFF_LATENCY, &latency_hist_reset_fops);
+#endif
+
+#ifdef CONFIG_PREEMPT_OFF_HIST
+       dentry = debugfs_create_dir(preemptoff_hist_dir,
+           latency_hist_root);
+       for_each_possible_cpu(i) {
+               sprintf(name, cpufmt, i);
+               entry = debugfs_create_file(name, 0444, dentry,
+                   &per_cpu(preemptoff_hist, i), &latency_hist_fops);
+               my_hist = &per_cpu(preemptoff_hist, i);
+               atomic_set(&my_hist->hist_mode, 1);
+               my_hist->min_lat = LONG_MAX;
+       }
+       entry = debugfs_create_file("reset", 0644, dentry,
+           (void *)PREEMPTOFF_LATENCY, &latency_hist_reset_fops);
+#endif
+
+#if defined(CONFIG_INTERRUPT_OFF_HIST) && defined(CONFIG_PREEMPT_OFF_HIST)
+       dentry = debugfs_create_dir(preemptirqsoff_hist_dir,
+           latency_hist_root);
+       for_each_possible_cpu(i) {
+               sprintf(name, cpufmt, i);
+               entry = debugfs_create_file(name, 0444, dentry,
+                   &per_cpu(preemptirqsoff_hist, i), &latency_hist_fops);
+               my_hist = &per_cpu(preemptirqsoff_hist, i);
+               atomic_set(&my_hist->hist_mode, 1);
+               my_hist->min_lat = LONG_MAX;
+       }
+       entry = debugfs_create_file("reset", 0644, dentry,
+           (void *)PREEMPTIRQSOFF_LATENCY, &latency_hist_reset_fops);
+#endif
+
+#if defined(CONFIG_INTERRUPT_OFF_HIST) || defined(CONFIG_PREEMPT_OFF_HIST)
+       entry = debugfs_create_file("preemptirqsoff", 0644,
+           enable_root, (void *)&preemptirqsoff_enabled_data,
+           &enable_fops);
+#endif
+
+#ifdef CONFIG_WAKEUP_LATENCY_HIST
+       dentry = debugfs_create_dir(wakeup_latency_hist_dir,
+           latency_hist_root);
+       dentry_sharedprio = debugfs_create_dir(
+           wakeup_latency_hist_dir_sharedprio, dentry);
+       for_each_possible_cpu(i) {
+               sprintf(name, cpufmt, i);
+
+               entry = debugfs_create_file(name, 0444, dentry,
+                   &per_cpu(wakeup_latency_hist, i),
+                   &latency_hist_fops);
+               my_hist = &per_cpu(wakeup_latency_hist, i);
+               atomic_set(&my_hist->hist_mode, 1);
+               my_hist->min_lat = LONG_MAX;
+
+               entry = debugfs_create_file(name, 0444, dentry_sharedprio,
+                   &per_cpu(wakeup_latency_hist_sharedprio, i),
+                   &latency_hist_fops);
+               my_hist = &per_cpu(wakeup_latency_hist_sharedprio, i);
+               atomic_set(&my_hist->hist_mode, 1);
+               my_hist->min_lat = LONG_MAX;
+
+               sprintf(name, cpufmt_maxlatproc, i);
+
+               mp = &per_cpu(wakeup_maxlatproc, i);
+               entry = debugfs_create_file(name, 0444, dentry, mp,
+                   &maxlatproc_fops);
+               clear_maxlatprocdata(mp);
+
+               mp = &per_cpu(wakeup_maxlatproc_sharedprio, i);
+               entry = debugfs_create_file(name, 0444, dentry_sharedprio, mp,
+                   &maxlatproc_fops);
+               clear_maxlatprocdata(mp);
+       }
+       entry = debugfs_create_file("pid", 0644, dentry,
+           (void *)&wakeup_pid, &pid_fops);
+       entry = debugfs_create_file("reset", 0644, dentry,
+           (void *)WAKEUP_LATENCY, &latency_hist_reset_fops);
+       entry = debugfs_create_file("reset", 0644, dentry_sharedprio,
+           (void *)WAKEUP_LATENCY_SHAREDPRIO, &latency_hist_reset_fops);
+       entry = debugfs_create_file("wakeup", 0644,
+           enable_root, (void *)&wakeup_latency_enabled_data,
+           &enable_fops);
+#endif
+
+#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST
+       dentry = debugfs_create_dir(missed_timer_offsets_dir,
+           latency_hist_root);
+       for_each_possible_cpu(i) {
+               sprintf(name, cpufmt, i);
+               entry = debugfs_create_file(name, 0444, dentry,
+                   &per_cpu(missed_timer_offsets, i), &latency_hist_fops);
+               my_hist = &per_cpu(missed_timer_offsets, i);
+               atomic_set(&my_hist->hist_mode, 1);
+               my_hist->min_lat = LONG_MAX;
+
+               sprintf(name, cpufmt_maxlatproc, i);
+               mp = &per_cpu(missed_timer_offsets_maxlatproc, i);
+               entry = debugfs_create_file(name, 0444, dentry, mp,
+                   &maxlatproc_fops);
+               clear_maxlatprocdata(mp);
+       }
+       entry = debugfs_create_file("pid", 0644, dentry,
+           (void *)&missed_timer_offsets_pid, &pid_fops);
+       entry = debugfs_create_file("reset", 0644, dentry,
+           (void *)MISSED_TIMER_OFFSETS, &latency_hist_reset_fops);
+       entry = debugfs_create_file("missed_timer_offsets", 0644,
+           enable_root, (void *)&missed_timer_offsets_enabled_data,
+           &enable_fops);
+#endif
+
+#if defined(CONFIG_WAKEUP_LATENCY_HIST) && \
+       defined(CONFIG_MISSED_TIMER_OFFSETS_HIST)
+       dentry = debugfs_create_dir(timerandwakeup_latency_hist_dir,
+           latency_hist_root);
+       for_each_possible_cpu(i) {
+               sprintf(name, cpufmt, i);
+               entry = debugfs_create_file(name, 0444, dentry,
+                   &per_cpu(timerandwakeup_latency_hist, i),
+                   &latency_hist_fops);
+               my_hist = &per_cpu(timerandwakeup_latency_hist, i);
+               atomic_set(&my_hist->hist_mode, 1);
+               my_hist->min_lat = LONG_MAX;
+
+               sprintf(name, cpufmt_maxlatproc, i);
+               mp = &per_cpu(timerandwakeup_maxlatproc, i);
+               entry = debugfs_create_file(name, 0444, dentry, mp,
+                   &maxlatproc_fops);
+               clear_maxlatprocdata(mp);
+       }
+       entry = debugfs_create_file("reset", 0644, dentry,
+           (void *)TIMERANDWAKEUP_LATENCY, &latency_hist_reset_fops);
+       entry = debugfs_create_file("timerandwakeup", 0644,
+           enable_root, (void *)&timerandwakeup_enabled_data,
+           &enable_fops);
+#endif
+       return 0;
+}
+
+device_initcall(latency_hist_init);
index 2d1d25a..ba2fa7c 100644 (file)
@@ -1927,6 +1927,7 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
        struct task_struct *tsk = current;
 
        entry->preempt_count            = pc & 0xff;
+       entry->preempt_lazy_count       = preempt_lazy_count();
        entry->pid                      = (tsk) ? tsk->pid : 0;
        entry->flags =
 #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
@@ -1937,8 +1938,11 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
                ((pc & NMI_MASK    ) ? TRACE_FLAG_NMI     : 0) |
                ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) |
                ((pc & SOFTIRQ_OFFSET) ? TRACE_FLAG_SOFTIRQ : 0) |
-               (tif_need_resched() ? TRACE_FLAG_NEED_RESCHED : 0) |
+               (tif_need_resched_now() ? TRACE_FLAG_NEED_RESCHED : 0) |
+               (need_resched_lazy() ? TRACE_FLAG_NEED_RESCHED_LAZY : 0) |
                (test_preempt_need_resched() ? TRACE_FLAG_PREEMPT_RESCHED : 0);
+
+       entry->migrate_disable = (tsk) ? __migrate_disabled(tsk) & 0xFF : 0;
 }
 EXPORT_SYMBOL_GPL(tracing_generic_entry_update);
 
@@ -2936,14 +2940,17 @@ get_total_entries(struct trace_buffer *buf,
 
 static void print_lat_help_header(struct seq_file *m)
 {
-       seq_puts(m, "#                  _------=> CPU#            \n"
-                   "#                 / _-----=> irqs-off        \n"
-                   "#                | / _----=> need-resched    \n"
-                   "#                || / _---=> hardirq/softirq \n"
-                   "#                ||| / _--=> preempt-depth   \n"
-                   "#                |||| /     delay            \n"
-                   "#  cmd     pid   ||||| time  |   caller      \n"
-                   "#     \\   /      |||||  \\    |   /         \n");
+       seq_puts(m, "#                  _--------=> CPU#              \n"
+                   "#                 / _-------=> irqs-off          \n"
+                   "#                | / _------=> need-resched      \n"
+                   "#                || / _-----=> need-resched_lazy \n"
+                   "#                ||| / _----=> hardirq/softirq   \n"
+                   "#                |||| / _---=> preempt-depth     \n"
+                   "#                ||||| / _--=> preempt-lazy-depth\n"
+                   "#                |||||| / _-=> migrate-disable   \n"
+                   "#                ||||||| /     delay             \n"
+                   "# cmd     pid    |||||||| time   |  caller       \n"
+                   "#     \\   /      ||||||||   \\    |  /            \n");
 }
 
 static void print_event_info(struct trace_buffer *buf, struct seq_file *m)
@@ -2976,11 +2983,14 @@ static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file
        print_event_info(buf, m);
        seq_puts(m, "#                              _-----=> irqs-off\n"
                    "#                             / _----=> need-resched\n"
-                   "#                            | / _---=> hardirq/softirq\n"
-                   "#                            || / _--=> preempt-depth\n"
-                   "#                            ||| /     delay\n"
-                   "#           TASK-PID   CPU#  ||||    TIMESTAMP  FUNCTION\n"
-                   "#              | |       |   ||||       |         |\n");
+                   "#                            |/  _-----=> need-resched_lazy\n"
+                   "#                            || / _---=> hardirq/softirq\n"
+                   "#                            ||| / _--=> preempt-depth\n"
+                   "#                            |||| / _-=> preempt-lazy-depth\n"
+                   "#                            ||||| / _-=> migrate-disable   \n"
+                   "#                            |||||| /    delay\n"
+                   "#           TASK-PID   CPU#  |||||||   TIMESTAMP  FUNCTION\n"
+                   "#              | |       |   |||||||      |         |\n");
 }
 
 static void print_func_help_header_irq_tgid(struct trace_buffer *buf, struct seq_file *m)
index 57ebf29..8797ec5 100644 (file)
@@ -124,6 +124,7 @@ struct kretprobe_trace_entry_head {
  *  NEED_RESCHED       - reschedule is requested
  *  HARDIRQ            - inside an interrupt handler
  *  SOFTIRQ            - inside a softirq handler
+ *  NEED_RESCHED_LAZY  - lazy reschedule is requested
  */
 enum trace_flag_type {
        TRACE_FLAG_IRQS_OFF             = 0x01,
@@ -133,6 +134,7 @@ enum trace_flag_type {
        TRACE_FLAG_SOFTIRQ              = 0x10,
        TRACE_FLAG_PREEMPT_RESCHED      = 0x20,
        TRACE_FLAG_NMI                  = 0x40,
+       TRACE_FLAG_NEED_RESCHED_LAZY    = 0x80,
 };
 
 #define TRACE_BUF_SIZE         1024
index 5bf072e..b374eae 100644 (file)
@@ -187,6 +187,8 @@ static int trace_define_common_fields(void)
        __common_field(unsigned char, flags);
        __common_field(unsigned char, preempt_count);
        __common_field(int, pid);
+       __common_field(unsigned short, migrate_disable);
+       __common_field(unsigned short, padding);
 
        return ret;
 }
index c180fe5..609a4fb 100644 (file)
@@ -13,6 +13,7 @@
 #include <linux/uaccess.h>
 #include <linux/module.h>
 #include <linux/ftrace.h>
+#include <trace/events/hist.h>
 
 #include "trace.h"
 
@@ -428,11 +429,13 @@ void start_critical_timings(void)
 {
        if (preempt_trace() || irq_trace())
                start_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
+       trace_preemptirqsoff_hist_rcuidle(TRACE_START, 1);
 }
 EXPORT_SYMBOL_GPL(start_critical_timings);
 
 void stop_critical_timings(void)
 {
+       trace_preemptirqsoff_hist_rcuidle(TRACE_STOP, 0);
        if (preempt_trace() || irq_trace())
                stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
 }
@@ -442,6 +445,7 @@ EXPORT_SYMBOL_GPL(stop_critical_timings);
 #ifdef CONFIG_PROVE_LOCKING
 void time_hardirqs_on(unsigned long a0, unsigned long a1)
 {
+       trace_preemptirqsoff_hist_rcuidle(IRQS_ON, 0);
        if (!preempt_trace() && irq_trace())
                stop_critical_timing(a0, a1);
 }
@@ -450,6 +454,7 @@ void time_hardirqs_off(unsigned long a0, unsigned long a1)
 {
        if (!preempt_trace() && irq_trace())
                start_critical_timing(a0, a1);
+       trace_preemptirqsoff_hist_rcuidle(IRQS_OFF, 1);
 }
 
 #else /* !CONFIG_PROVE_LOCKING */
@@ -459,6 +464,7 @@ void time_hardirqs_off(unsigned long a0, unsigned long a1)
  */
 static inline void tracer_hardirqs_on(void)
 {
+       trace_preemptirqsoff_hist(IRQS_ON, 0);
        if (!preempt_trace() && irq_trace())
                stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
 }
@@ -467,10 +473,12 @@ static inline void tracer_hardirqs_off(void)
 {
        if (!preempt_trace() && irq_trace())
                start_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
+       trace_preemptirqsoff_hist(IRQS_OFF, 1);
 }
 
 static inline void tracer_hardirqs_on_caller(unsigned long caller_addr)
 {
+       trace_preemptirqsoff_hist(IRQS_ON, 0);
        if (!preempt_trace() && irq_trace())
                stop_critical_timing(CALLER_ADDR0, caller_addr);
 }
@@ -479,6 +487,7 @@ static inline void tracer_hardirqs_off_caller(unsigned long caller_addr)
 {
        if (!preempt_trace() && irq_trace())
                start_critical_timing(CALLER_ADDR0, caller_addr);
+       trace_preemptirqsoff_hist(IRQS_OFF, 1);
 }
 
 #endif /* CONFIG_PROVE_LOCKING */
@@ -487,12 +496,14 @@ static inline void tracer_hardirqs_off_caller(unsigned long caller_addr)
 #ifdef CONFIG_PREEMPT_TRACER
 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1)
 {
+       trace_preemptirqsoff_hist(PREEMPT_ON, 0);
        if (preempt_trace() && !irq_trace())
                stop_critical_timing(a0, a1);
 }
 
 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1)
 {
+       trace_preemptirqsoff_hist(PREEMPT_ON, 1);
        if (preempt_trace() && !irq_trace())
                start_critical_timing(a0, a1);
 }
index 0346759..8da8d50 100644 (file)
@@ -386,6 +386,7 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 {
        char hardsoft_irq;
        char need_resched;
+       char need_resched_lazy;
        char irqs_off;
        int hardirq;
        int softirq;
@@ -416,6 +417,9 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
                break;
        }
 
+       need_resched_lazy =
+               (entry->flags & TRACE_FLAG_NEED_RESCHED_LAZY) ? 'L' : '.';
+
        hardsoft_irq =
                (nmi && hardirq)     ? 'Z' :
                nmi                  ? 'z' :
@@ -424,14 +428,25 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
                softirq              ? 's' :
                                       '.' ;
 
-       trace_seq_printf(s, "%c%c%c",
-                        irqs_off, need_resched, hardsoft_irq);
+       trace_seq_printf(s, "%c%c%c%c",
+                        irqs_off, need_resched, need_resched_lazy,
+                        hardsoft_irq);
 
        if (entry->preempt_count)
                trace_seq_printf(s, "%x", entry->preempt_count);
        else
                trace_seq_putc(s, '.');
 
+       if (entry->preempt_lazy_count)
+               trace_seq_printf(s, "%x", entry->preempt_lazy_count);
+       else
+               trace_seq_putc(s, '.');
+
+       if (entry->migrate_disable)
+               trace_seq_printf(s, "%x", entry->migrate_disable);
+       else
+               trace_seq_putc(s, '.');
+
        return !trace_seq_has_overflowed(s);
 }
 
index 41e94e4..8780af7 100644 (file)
@@ -162,11 +162,11 @@ void free_uid(struct user_struct *up)
        if (!up)
                return;
 
-       local_irq_save(flags);
+       local_irq_save_nort(flags);
        if (atomic_dec_and_lock(&up->__count, &uidhash_lock))
                free_user(up, flags);
        else
-               local_irq_restore(flags);
+               local_irq_restore_nort(flags);
 }
 
 struct user_struct *alloc_uid(kuid_t uid)
index 9df5ac2..2b5a39e 100644 (file)
@@ -392,6 +392,7 @@ static void watchdog_enable(unsigned int cpu)
        /* kick off the timer for the hardlockup detector */
        hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
        hrtimer->function = watchdog_timer_fn;
+       hrtimer->irqsafe = 1;
 
        /* Enable the perf event */
        watchdog_nmi_enable(cpu);
index 9a42b8b..bd4f0b4 100644 (file)
@@ -23,6 +23,7 @@ static cpumask_t __read_mostly watchdog_cpus;
 #endif
 #ifdef CONFIG_HARDLOCKUP_DETECTOR_NMI
 static DEFINE_PER_CPU(struct perf_event *, watchdog_ev);
+static DEFINE_RAW_SPINLOCK(watchdog_output_lock);
 #endif
 DECLARE_PER_CPU(unsigned long, hrtimer_interrupts);
 DECLARE_PER_CPU(unsigned long, hrtimer_interrupts_saved);
@@ -112,6 +113,13 @@ static void watchdog_overflow_callback(struct perf_event *event,
                /* only print hardlockups once */
                if (__this_cpu_read(hard_watchdog_warn) == true)
                        return;
+               /*
+                * If early-printk is enabled then make sure we do not
+                * lock up in printk() and kill console logging:
+                */
+               printk_kill();
+
+               raw_spin_lock(&watchdog_output_lock);
 
                pr_emerg("Watchdog detected hard LOCKUP on cpu %d", this_cpu);
                print_modules();
@@ -132,6 +140,7 @@ static void watchdog_overflow_callback(struct perf_event *event,
 #ifdef CONFIG_AMLOGIC_DEBUG_LOCKUP
                pr_lockup_info(next_cpu);
 #endif
+               raw_spin_unlock(&watchdog_output_lock);
                if (hardlockup_panic)
                        nmi_panic(regs, "Hard LOCKUP");
 
index 1ed736d..a92480b 100644 (file)
@@ -48,6 +48,8 @@
 #include <linux/nodemask.h>
 #include <linux/moduleparam.h>
 #include <linux/uaccess.h>
+#include <linux/locallock.h>
+#include <linux/delay.h>
 #include <linux/nmi.h>
 
 #include "workqueue_internal.h"
@@ -123,11 +125,16 @@ enum {
  *    cpu or grabbing pool->lock is enough for read access.  If
  *    POOL_DISASSOCIATED is set, it's identical to L.
  *
+ *    On RT we need the extra protection via rt_lock_idle_list() for
+ *    the list manipulations against read access from
+ *    wq_worker_sleeping(). All other places are nicely serialized via
+ *    pool->lock.
+ *
  * A: pool->attach_mutex protected.
  *
  * PL: wq_pool_mutex protected.
  *
- * PR: wq_pool_mutex protected for writes.  Sched-RCU protected for reads.
+ * PR: wq_pool_mutex protected for writes.  RCU protected for reads.
  *
  * PW: wq_pool_mutex and wq->mutex protected for writes.  Either for reads.
  *
@@ -136,7 +143,7 @@ enum {
  *
  * WQ: wq->mutex protected.
  *
- * WR: wq->mutex protected for writes.  Sched-RCU protected for reads.
+ * WR: wq->mutex protected for writes.  RCU protected for reads.
  *
  * MD: wq_mayday_lock protected.
  */
@@ -186,7 +193,7 @@ struct worker_pool {
        atomic_t                nr_running ____cacheline_aligned_in_smp;
 
        /*
-        * Destruction of pool is sched-RCU protected to allow dereferences
+        * Destruction of pool is RCU protected to allow dereferences
         * from get_work_pool().
         */
        struct rcu_head         rcu;
@@ -215,7 +222,7 @@ struct pool_workqueue {
        /*
         * Release of unbound pwq is punted to system_wq.  See put_pwq()
         * and pwq_unbound_release_workfn() for details.  pool_workqueue
-        * itself is also sched-RCU protected so that the first pwq can be
+        * itself is also RCU protected so that the first pwq can be
         * determined without grabbing wq->mutex.
         */
        struct work_struct      unbound_release_work;
@@ -350,6 +357,8 @@ EXPORT_SYMBOL_GPL(system_power_efficient_wq);
 struct workqueue_struct *system_freezable_power_efficient_wq __read_mostly;
 EXPORT_SYMBOL_GPL(system_freezable_power_efficient_wq);
 
+static DEFINE_LOCAL_IRQ_LOCK(pendingb_lock);
+
 static int worker_thread(void *__worker);
 static void workqueue_sysfs_unregister(struct workqueue_struct *wq);
 
@@ -357,20 +366,20 @@ static void workqueue_sysfs_unregister(struct workqueue_struct *wq);
 #include <trace/events/workqueue.h>
 
 #define assert_rcu_or_pool_mutex()                                     \
-       RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held() &&                 \
+       RCU_LOCKDEP_WARN(!rcu_read_lock_held() &&                       \
                         !lockdep_is_held(&wq_pool_mutex),              \
-                        "sched RCU or wq_pool_mutex should be held")
+                        "RCU or wq_pool_mutex should be held")
 
 #define assert_rcu_or_wq_mutex(wq)                                     \
-       RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held() &&                 \
+       RCU_LOCKDEP_WARN(!rcu_read_lock_held() &&                       \
                         !lockdep_is_held(&wq->mutex),                  \
-                        "sched RCU or wq->mutex should be held")
+                        "RCU or wq->mutex should be held")
 
 #define assert_rcu_or_wq_mutex_or_pool_mutex(wq)                       \
-       RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held() &&                 \
+       RCU_LOCKDEP_WARN(!rcu_read_lock_held() &&                       \
                         !lockdep_is_held(&wq->mutex) &&                \
                         !lockdep_is_held(&wq_pool_mutex),              \
-                        "sched RCU, wq->mutex or wq_pool_mutex should be held")
+                        "RCU, wq->mutex or wq_pool_mutex should be held")
 
 #define for_each_cpu_worker_pool(pool, cpu)                            \
        for ((pool) = &per_cpu(cpu_worker_pools, cpu)[0];               \
@@ -382,7 +391,7 @@ static void workqueue_sysfs_unregister(struct workqueue_struct *wq);
  * @pool: iteration cursor
  * @pi: integer used for iteration
  *
- * This must be called either with wq_pool_mutex held or sched RCU read
+ * This must be called either with wq_pool_mutex held or RCU read
  * locked.  If the pool needs to be used beyond the locking in effect, the
  * caller is responsible for guaranteeing that the pool stays online.
  *
@@ -414,7 +423,7 @@ static void workqueue_sysfs_unregister(struct workqueue_struct *wq);
  * @pwq: iteration cursor
  * @wq: the target workqueue
  *
- * This must be called either with wq->mutex held or sched RCU read locked.
+ * This must be called either with wq->mutex held or RCU read locked.
  * If the pwq needs to be used beyond the locking in effect, the caller is
  * responsible for guaranteeing that the pwq stays online.
  *
@@ -426,6 +435,31 @@ static void workqueue_sysfs_unregister(struct workqueue_struct *wq);
                if (({ assert_rcu_or_wq_mutex(wq); false; })) { }       \
                else
 
+#ifdef CONFIG_PREEMPT_RT_BASE
+static inline void rt_lock_idle_list(struct worker_pool *pool)
+{
+       preempt_disable();
+}
+static inline void rt_unlock_idle_list(struct worker_pool *pool)
+{
+       preempt_enable();
+}
+static inline void sched_lock_idle_list(struct worker_pool *pool) { }
+static inline void sched_unlock_idle_list(struct worker_pool *pool) { }
+#else
+static inline void rt_lock_idle_list(struct worker_pool *pool) { }
+static inline void rt_unlock_idle_list(struct worker_pool *pool) { }
+static inline void sched_lock_idle_list(struct worker_pool *pool)
+{
+       spin_lock_irq(&pool->lock);
+}
+static inline void sched_unlock_idle_list(struct worker_pool *pool)
+{
+       spin_unlock_irq(&pool->lock);
+}
+#endif
+
+
 #ifdef CONFIG_DEBUG_OBJECTS_WORK
 
 static struct debug_obj_descr work_debug_descr;
@@ -550,7 +584,7 @@ static int worker_pool_assign_id(struct worker_pool *pool)
  * @wq: the target workqueue
  * @node: the node ID
  *
- * This must be called with any of wq_pool_mutex, wq->mutex or sched RCU
+ * This must be called with any of wq_pool_mutex, wq->mutex or RCU
  * read locked.
  * If the pwq needs to be used beyond the locking in effect, the caller is
  * responsible for guaranteeing that the pwq stays online.
@@ -694,8 +728,8 @@ static struct pool_workqueue *get_work_pwq(struct work_struct *work)
  * @work: the work item of interest
  *
  * Pools are created and destroyed under wq_pool_mutex, and allows read
- * access under sched-RCU read lock.  As such, this function should be
- * called under wq_pool_mutex or with preemption disabled.
+ * access under RCU read lock.  As such, this function should be
+ * called under wq_pool_mutex or inside of a rcu_read_lock() region.
  *
  * All fields of the returned pool are accessible as long as the above
  * mentioned locking is in effect.  If the returned pool needs to be used
@@ -832,50 +866,45 @@ static struct worker *first_idle_worker(struct worker_pool *pool)
  */
 static void wake_up_worker(struct worker_pool *pool)
 {
-       struct worker *worker = first_idle_worker(pool);
+       struct worker *worker;
+
+       rt_lock_idle_list(pool);
+
+       worker = first_idle_worker(pool);
 
        if (likely(worker))
                wake_up_process(worker->task);
+
+       rt_unlock_idle_list(pool);
 }
 
 /**
- * wq_worker_waking_up - a worker is waking up
+ * wq_worker_running - a worker is running again
  * @task: task waking up
- * @cpu: CPU @task is waking up to
  *
- * This function is called during try_to_wake_up() when a worker is
- * being awoken.
- *
- * CONTEXT:
- * spin_lock_irq(rq->lock)
+ * This function is called when a worker returns from schedule()
  */
-void wq_worker_waking_up(struct task_struct *task, int cpu)
+void wq_worker_running(struct task_struct *task)
 {
        struct worker *worker = kthread_data(task);
 
-       if (!(worker->flags & WORKER_NOT_RUNNING)) {
-               WARN_ON_ONCE(worker->pool->cpu != cpu);
+       if (!worker->sleeping)
+               return;
+       if (!(worker->flags & WORKER_NOT_RUNNING))
                atomic_inc(&worker->pool->nr_running);
-       }
+       worker->sleeping = 0;
 }
 
 /**
  * wq_worker_sleeping - a worker is going to sleep
  * @task: task going to sleep
  *
- * This function is called during schedule() when a busy worker is
- * going to sleep.  Worker on the same cpu can be woken up by
- * returning pointer to its task.
- *
- * CONTEXT:
- * spin_lock_irq(rq->lock)
- *
- * Return:
- * Worker task on @cpu to wake up, %NULL if none.
+ * This function is called from schedule() when a busy worker is
+ * going to sleep.
  */
-struct task_struct *wq_worker_sleeping(struct task_struct *task)
+void wq_worker_sleeping(struct task_struct *task)
 {
-       struct worker *worker = kthread_data(task), *to_wakeup = NULL;
+       struct worker *worker = kthread_data(task);
        struct worker_pool *pool;
 
        /*
@@ -884,29 +913,26 @@ struct task_struct *wq_worker_sleeping(struct task_struct *task)
         * checking NOT_RUNNING.
         */
        if (worker->flags & WORKER_NOT_RUNNING)
-               return NULL;
+               return;
 
        pool = worker->pool;
 
-       /* this can only happen on the local cpu */
-       if (WARN_ON_ONCE(pool->cpu != raw_smp_processor_id()))
-               return NULL;
+       if (WARN_ON_ONCE(worker->sleeping))
+               return;
+
+       worker->sleeping = 1;
 
        /*
         * The counterpart of the following dec_and_test, implied mb,
         * worklist not empty test sequence is in insert_work().
         * Please read comment there.
-        *
-        * NOT_RUNNING is clear.  This means that we're bound to and
-        * running on the local cpu w/ rq lock held and preemption
-        * disabled, which in turn means that none else could be
-        * manipulating idle_list, so dereferencing idle_list without pool
-        * lock is safe.
         */
        if (atomic_dec_and_test(&pool->nr_running) &&
-           !list_empty(&pool->worklist))
-               to_wakeup = first_idle_worker(pool);
-       return to_wakeup ? to_wakeup->task : NULL;
+           !list_empty(&pool->worklist)) {
+               sched_lock_idle_list(pool);
+               wake_up_worker(pool);
+               sched_unlock_idle_list(pool);
+       }
 }
 
 /**
@@ -1100,12 +1126,14 @@ static void put_pwq_unlocked(struct pool_workqueue *pwq)
 {
        if (pwq) {
                /*
-                * As both pwqs and pools are sched-RCU protected, the
+                * As both pwqs and pools are RCU protected, the
                 * following lock operations are safe.
                 */
-               spin_lock_irq(&pwq->pool->lock);
+               rcu_read_lock();
+               local_spin_lock_irq(pendingb_lock, &pwq->pool->lock);
                put_pwq(pwq);
-               spin_unlock_irq(&pwq->pool->lock);
+               local_spin_unlock_irq(pendingb_lock, &pwq->pool->lock);
+               rcu_read_unlock();
        }
 }
 
@@ -1209,7 +1237,7 @@ static int try_to_grab_pending(struct work_struct *work, bool is_dwork,
        struct worker_pool *pool;
        struct pool_workqueue *pwq;
 
-       local_irq_save(*flags);
+       local_lock_irqsave(pendingb_lock, *flags);
 
        /* try to steal the timer if it exists */
        if (is_dwork) {
@@ -1228,6 +1256,7 @@ static int try_to_grab_pending(struct work_struct *work, bool is_dwork,
        if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work)))
                return 0;
 
+       rcu_read_lock();
        /*
         * The queueing is in progress, or it is already queued. Try to
         * steal it from ->worklist without clearing WORK_STRUCT_PENDING.
@@ -1266,14 +1295,16 @@ static int try_to_grab_pending(struct work_struct *work, bool is_dwork,
                set_work_pool_and_keep_pending(work, pool->id);
 
                spin_unlock(&pool->lock);
+               rcu_read_unlock();
                return 1;
        }
        spin_unlock(&pool->lock);
 fail:
-       local_irq_restore(*flags);
+       rcu_read_unlock();
+       local_unlock_irqrestore(pendingb_lock, *flags);
        if (work_is_canceling(work))
                return -ENOENT;
-       cpu_relax();
+       cpu_chill();
        return -EAGAIN;
 }
 
@@ -1375,7 +1406,7 @@ static void __queue_work(int cpu, struct workqueue_struct *wq,
         * queued or lose PENDING.  Grabbing PENDING and queueing should
         * happen with IRQ disabled.
         */
-       WARN_ON_ONCE(!irqs_disabled());
+       WARN_ON_ONCE_NONRT(!irqs_disabled());
 
        debug_work_activate(work);
 
@@ -1383,6 +1414,7 @@ static void __queue_work(int cpu, struct workqueue_struct *wq,
        if (unlikely(wq->flags & __WQ_DRAINING) &&
            WARN_ON_ONCE(!is_chained_work(wq)))
                return;
+       rcu_read_lock();
 retry:
        /* pwq which will be used unless @work is executing elsewhere */
        if (wq->flags & WQ_UNBOUND) {
@@ -1441,10 +1473,8 @@ retry:
        /* pwq determined, queue */
        trace_workqueue_queue_work(req_cpu, pwq, work);
 
-       if (WARN_ON(!list_empty(&work->entry))) {
-               spin_unlock(&pwq->pool->lock);
-               return;
-       }
+       if (WARN_ON(!list_empty(&work->entry)))
+               goto out;
 
        pwq->nr_in_flight[pwq->work_color]++;
        work_flags = work_color_to_flags(pwq->work_color);
@@ -1462,7 +1492,9 @@ retry:
 
        insert_work(pwq, work, worklist, work_flags);
 
+out:
        spin_unlock(&pwq->pool->lock);
+       rcu_read_unlock();
 }
 
 /**
@@ -1482,14 +1514,14 @@ bool queue_work_on(int cpu, struct workqueue_struct *wq,
        bool ret = false;
        unsigned long flags;
 
-       local_irq_save(flags);
+       local_lock_irqsave(pendingb_lock,flags);
 
        if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))) {
                __queue_work(cpu, wq, work);
                ret = true;
        }
 
-       local_irq_restore(flags);
+       local_unlock_irqrestore(pendingb_lock, flags);
        return ret;
 }
 EXPORT_SYMBOL(queue_work_on);
@@ -1557,14 +1589,14 @@ bool queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
        unsigned long flags;
 
        /* read the comment in __queue_work() */
-       local_irq_save(flags);
+       local_lock_irqsave(pendingb_lock, flags);
 
        if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))) {
                __queue_delayed_work(cpu, wq, dwork, delay);
                ret = true;
        }
 
-       local_irq_restore(flags);
+       local_unlock_irqrestore(pendingb_lock, flags);
        return ret;
 }
 EXPORT_SYMBOL(queue_delayed_work_on);
@@ -1599,7 +1631,7 @@ bool mod_delayed_work_on(int cpu, struct workqueue_struct *wq,
 
        if (likely(ret >= 0)) {
                __queue_delayed_work(cpu, wq, dwork, delay);
-               local_irq_restore(flags);
+               local_unlock_irqrestore(pendingb_lock, flags);
        }
 
        /* -ENOENT from try_to_grab_pending() becomes %true */
@@ -1632,7 +1664,9 @@ static void worker_enter_idle(struct worker *worker)
        worker->last_active = jiffies;
 
        /* idle_list is LIFO */
+       rt_lock_idle_list(pool);
        list_add(&worker->entry, &pool->idle_list);
+       rt_unlock_idle_list(pool);
 
        if (too_many_workers(pool) && !timer_pending(&pool->idle_timer))
                mod_timer(&pool->idle_timer, jiffies + IDLE_WORKER_TIMEOUT);
@@ -1665,7 +1699,9 @@ static void worker_leave_idle(struct worker *worker)
                return;
        worker_clr_flags(worker, WORKER_IDLE);
        pool->nr_idle--;
+       rt_lock_idle_list(pool);
        list_del_init(&worker->entry);
+       rt_unlock_idle_list(pool);
 }
 
 static struct worker *alloc_worker(int node)
@@ -1831,7 +1867,9 @@ static void destroy_worker(struct worker *worker)
        pool->nr_workers--;
        pool->nr_idle--;
 
+       rt_lock_idle_list(pool);
        list_del_init(&worker->entry);
+       rt_unlock_idle_list(pool);
        worker->flags |= WORKER_DIE;
        wake_up_process(worker->task);
 }
@@ -2808,14 +2846,14 @@ static bool start_flush_work(struct work_struct *work, struct wq_barrier *barr)
 
        might_sleep();
 
-       local_irq_disable();
+       rcu_read_lock();
        pool = get_work_pool(work);
        if (!pool) {
-               local_irq_enable();
+               rcu_read_unlock();
                return false;
        }
 
-       spin_lock(&pool->lock);
+       spin_lock_irq(&pool->lock);
        /* see the comment in try_to_grab_pending() with the same code */
        pwq = get_work_pwq(work);
        if (pwq) {
@@ -2844,10 +2882,11 @@ static bool start_flush_work(struct work_struct *work, struct wq_barrier *barr)
        else
                lock_map_acquire_read(&pwq->wq->lockdep_map);
        lock_map_release(&pwq->wq->lockdep_map);
-
+       rcu_read_unlock();
        return true;
 already_gone:
        spin_unlock_irq(&pool->lock);
+       rcu_read_unlock();
        return false;
 }
 
@@ -2934,7 +2973,7 @@ static bool __cancel_work_timer(struct work_struct *work, bool is_dwork)
 
        /* tell other tasks trying to grab @work to back off */
        mark_work_canceling(work);
-       local_irq_restore(flags);
+       local_unlock_irqrestore(pendingb_lock, flags);
 
        flush_work(work);
        clear_work_data(work);
@@ -2989,10 +3028,10 @@ EXPORT_SYMBOL_GPL(cancel_work_sync);
  */
 bool flush_delayed_work(struct delayed_work *dwork)
 {
-       local_irq_disable();
+       local_lock_irq(pendingb_lock);
        if (del_timer_sync(&dwork->timer))
                __queue_work(dwork->cpu, dwork->wq, &dwork->work);
-       local_irq_enable();
+       local_unlock_irq(pendingb_lock);
        return flush_work(&dwork->work);
 }
 EXPORT_SYMBOL(flush_delayed_work);
@@ -3010,7 +3049,7 @@ static bool __cancel_work(struct work_struct *work, bool is_dwork)
                return false;
 
        set_work_pool_and_clear_pending(work, get_work_pool_id(work));
-       local_irq_restore(flags);
+       local_unlock_irqrestore(pendingb_lock, flags);
        return ret;
 }
 
@@ -3267,7 +3306,7 @@ static void rcu_free_pool(struct rcu_head *rcu)
  * put_unbound_pool - put a worker_pool
  * @pool: worker_pool to put
  *
- * Put @pool.  If its refcnt reaches zero, it gets destroyed in sched-RCU
+ * Put @pool.  If its refcnt reaches zero, it gets destroyed in RCU
  * safe manner.  get_unbound_pool() calls this function on its failure path
  * and this function should be able to release pools which went through,
  * successfully or not, init_worker_pool().
@@ -3321,8 +3360,8 @@ static void put_unbound_pool(struct worker_pool *pool)
        del_timer_sync(&pool->idle_timer);
        del_timer_sync(&pool->mayday_timer);
 
-       /* sched-RCU protected to allow dereferences from get_work_pool() */
-       call_rcu_sched(&pool->rcu, rcu_free_pool);
+       /* RCU protected to allow dereferences from get_work_pool() */
+       call_rcu(&pool->rcu, rcu_free_pool);
 }
 
 /**
@@ -3429,14 +3468,14 @@ static void pwq_unbound_release_workfn(struct work_struct *work)
        put_unbound_pool(pool);
        mutex_unlock(&wq_pool_mutex);
 
-       call_rcu_sched(&pwq->rcu, rcu_free_pwq);
+       call_rcu(&pwq->rcu, rcu_free_pwq);
 
        /*
         * If we're the last pwq going away, @wq is already dead and no one
         * is gonna access it anymore.  Schedule RCU free.
         */
        if (is_last)
-               call_rcu_sched(&wq->rcu, rcu_free_wq);
+               call_rcu(&wq->rcu, rcu_free_wq);
 }
 
 /**
@@ -4115,7 +4154,7 @@ void destroy_workqueue(struct workqueue_struct *wq)
                 * The base ref is never dropped on per-cpu pwqs.  Directly
                 * schedule RCU free.
                 */
-               call_rcu_sched(&wq->rcu, rcu_free_wq);
+               call_rcu(&wq->rcu, rcu_free_wq);
        } else {
                /*
                 * We're the sole accessor of @wq at this point.  Directly
@@ -4225,7 +4264,8 @@ bool workqueue_congested(int cpu, struct workqueue_struct *wq)
        struct pool_workqueue *pwq;
        bool ret;
 
-       rcu_read_lock_sched();
+       rcu_read_lock();
+       preempt_disable();
 
        if (cpu == WORK_CPU_UNBOUND)
                cpu = smp_processor_id();
@@ -4236,7 +4276,8 @@ bool workqueue_congested(int cpu, struct workqueue_struct *wq)
                pwq = unbound_pwq_by_node(wq, cpu_to_node(cpu));
 
        ret = !list_empty(&pwq->delayed_works);
-       rcu_read_unlock_sched();
+       preempt_enable();
+       rcu_read_unlock();
 
        return ret;
 }
@@ -4262,15 +4303,15 @@ unsigned int work_busy(struct work_struct *work)
        if (work_pending(work))
                ret |= WORK_BUSY_PENDING;
 
-       local_irq_save(flags);
+       rcu_read_lock();
        pool = get_work_pool(work);
        if (pool) {
-               spin_lock(&pool->lock);
+               spin_lock_irqsave(&pool->lock, flags);
                if (find_worker_executing_work(pool, work))
                        ret |= WORK_BUSY_RUNNING;
-               spin_unlock(&pool->lock);
+               spin_unlock_irqrestore(&pool->lock, flags);
        }
-       local_irq_restore(flags);
+       rcu_read_unlock();
 
        return ret;
 }
@@ -4460,7 +4501,7 @@ void show_workqueue_state(void)
        unsigned long flags;
        int pi;
 
-       rcu_read_lock_sched();
+       rcu_read_lock();
 
        pr_info("Showing busy workqueues and worker pools:\n");
 
@@ -4525,7 +4566,7 @@ void show_workqueue_state(void)
                touch_nmi_watchdog();
        }
 
-       rcu_read_unlock_sched();
+       rcu_read_unlock();
 }
 
 /*
@@ -4863,16 +4904,16 @@ bool freeze_workqueues_busy(void)
                 * nr_active is monotonically decreasing.  It's safe
                 * to peek without lock.
                 */
-               rcu_read_lock_sched();
+               rcu_read_lock();
                for_each_pwq(pwq, wq) {
                        WARN_ON_ONCE(pwq->nr_active < 0);
                        if (pwq->nr_active) {
                                busy = true;
-                               rcu_read_unlock_sched();
+                               rcu_read_unlock();
                                goto out_unlock;
                        }
                }
-               rcu_read_unlock_sched();
+               rcu_read_unlock();
        }
 out_unlock:
        mutex_unlock(&wq_pool_mutex);
@@ -5062,7 +5103,8 @@ static ssize_t wq_pool_ids_show(struct device *dev,
        const char *delim = "";
        int node, written = 0;
 
-       rcu_read_lock_sched();
+       get_online_cpus();
+       rcu_read_lock();
        for_each_node(node) {
                written += scnprintf(buf + written, PAGE_SIZE - written,
                                     "%s%d:%d", delim, node,
@@ -5070,7 +5112,8 @@ static ssize_t wq_pool_ids_show(struct device *dev,
                delim = " ";
        }
        written += scnprintf(buf + written, PAGE_SIZE - written, "\n");
-       rcu_read_unlock_sched();
+       rcu_read_unlock();
+       put_online_cpus();
 
        return written;
 }
index 29fa81f..42d1e39 100644 (file)
@@ -44,6 +44,7 @@ struct worker {
        unsigned long           last_active;    /* L: last active timestamp */
        unsigned int            flags;          /* X: flags */
        int                     id;             /* I: worker id */
+       int                     sleeping;       /* None */
 
        /*
         * Opaque string set with work_set_desc().  Printed out with task
@@ -69,7 +70,7 @@ static inline struct worker *current_wq_worker(void)
  * Scheduler hooks for concurrency managed workqueue.  Only to be used from
  * sched/core.c and workqueue.c.
  */
-void wq_worker_waking_up(struct task_struct *task, int cpu);
-struct task_struct *wq_worker_sleeping(struct task_struct *task);
+void wq_worker_running(struct task_struct *task);
+void wq_worker_sleeping(struct task_struct *task);
 
 #endif /* _KERNEL_WORKQUEUE_INTERNAL_H */
index 2614753..3b1d944 100644 (file)
@@ -419,6 +419,7 @@ config CHECK_SIGNATURE
 
 config CPUMASK_OFFSTACK
        bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS
+       depends on !PREEMPT_RT_FULL
        help
          Use dynamic allocation for cpumask_var_t, instead of putting
          them on the stack.  This is a bit more expensive, but avoids
index 1c43d4c..43872a0 100644 (file)
@@ -311,7 +311,10 @@ __debug_object_init(void *addr, struct debug_obj_descr *descr, int onstack)
        struct debug_obj *obj;
        unsigned long flags;
 
-       fill_pool();
+#ifdef CONFIG_PREEMPT_RT_FULL
+       if (preempt_count() == 0 && !irqs_disabled())
+#endif
+               fill_pool();
 
        db = get_bucket((unsigned long) addr);
 
index 6098336..9decbe9 100644 (file)
--- a/lib/idr.c
+++ b/lib/idr.c
@@ -30,6 +30,7 @@
 #include <linux/idr.h>
 #include <linux/spinlock.h>
 #include <linux/percpu.h>
+#include <linux/locallock.h>
 
 #define MAX_IDR_SHIFT          (sizeof(int) * 8 - 1)
 #define MAX_IDR_BIT            (1U << MAX_IDR_SHIFT)
@@ -45,6 +46,37 @@ static DEFINE_PER_CPU(struct idr_layer *, idr_preload_head);
 static DEFINE_PER_CPU(int, idr_preload_cnt);
 static DEFINE_SPINLOCK(simple_ida_lock);
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+static DEFINE_LOCAL_IRQ_LOCK(idr_lock);
+
+static inline void idr_preload_lock(void)
+{
+       local_lock(idr_lock);
+}
+
+static inline void idr_preload_unlock(void)
+{
+       local_unlock(idr_lock);
+}
+
+void idr_preload_end(void)
+{
+       idr_preload_unlock();
+}
+EXPORT_SYMBOL(idr_preload_end);
+#else
+static inline void idr_preload_lock(void)
+{
+       preempt_disable();
+}
+
+static inline void idr_preload_unlock(void)
+{
+       preempt_enable();
+}
+#endif
+
+
 /* the maximum ID which can be allocated given idr->layers */
 static int idr_max(int layers)
 {
@@ -115,14 +147,14 @@ static struct idr_layer *idr_layer_alloc(gfp_t gfp_mask, struct idr *layer_idr)
         * context.  See idr_preload() for details.
         */
        if (!in_interrupt()) {
-               preempt_disable();
+               idr_preload_lock();
                new = __this_cpu_read(idr_preload_head);
                if (new) {
                        __this_cpu_write(idr_preload_head, new->ary[0]);
                        __this_cpu_dec(idr_preload_cnt);
                        new->ary[0] = NULL;
                }
-               preempt_enable();
+               idr_preload_unlock();
                if (new)
                        return new;
        }
@@ -366,7 +398,6 @@ static void idr_fill_slot(struct idr *idr, void *ptr, int id,
        idr_mark_full(pa, id);
 }
 
-
 /**
  * idr_preload - preload for idr_alloc()
  * @gfp_mask: allocation mask to use for preloading
@@ -401,7 +432,7 @@ void idr_preload(gfp_t gfp_mask)
        WARN_ON_ONCE(in_interrupt());
        might_sleep_if(gfpflags_allow_blocking(gfp_mask));
 
-       preempt_disable();
+       idr_preload_lock();
 
        /*
         * idr_alloc() is likely to succeed w/o full idr_layer buffer and
@@ -413,9 +444,9 @@ void idr_preload(gfp_t gfp_mask)
        while (__this_cpu_read(idr_preload_cnt) < MAX_IDR_FREE) {
                struct idr_layer *new;
 
-               preempt_enable();
+               idr_preload_unlock();
                new = kmem_cache_zalloc(idr_layer_cache, gfp_mask);
-               preempt_disable();
+               idr_preload_lock();
                if (!new)
                        break;
 
index 1d6565e..b23a797 100644 (file)
@@ -36,6 +36,7 @@ void irq_poll_sched(struct irq_poll *iop)
        list_add_tail(&iop->list, this_cpu_ptr(&blk_cpu_iopoll));
        __raise_softirq_irqoff(IRQ_POLL_SOFTIRQ);
        local_irq_restore(flags);
+       preempt_check_resched_rt();
 }
 EXPORT_SYMBOL(irq_poll_sched);
 
@@ -71,6 +72,7 @@ void irq_poll_complete(struct irq_poll *iop)
        local_irq_save(flags);
        __irq_poll_complete(iop);
        local_irq_restore(flags);
+       preempt_check_resched_rt();
 }
 EXPORT_SYMBOL(irq_poll_complete);
 
@@ -95,6 +97,7 @@ static void __latent_entropy irq_poll_softirq(struct softirq_action *h)
                }
 
                local_irq_enable();
+               preempt_check_resched_rt();
 
                /* Even though interrupts have been re-enabled, this
                 * access is safe because interrupts can only add new
@@ -132,6 +135,7 @@ static void __latent_entropy irq_poll_softirq(struct softirq_action *h)
                __raise_softirq_irqoff(IRQ_POLL_SOFTIRQ);
 
        local_irq_enable();
+       preempt_check_resched_rt();
 }
 
 /**
@@ -195,6 +199,7 @@ static int irq_poll_cpu_dead(unsigned int cpu)
                         this_cpu_ptr(&blk_cpu_iopoll));
        __raise_softirq_irqoff(IRQ_POLL_SOFTIRQ);
        local_irq_enable();
+       preempt_check_resched_rt();
 
        return 0;
 }
index f3a217e..4611b15 100644 (file)
@@ -590,6 +590,8 @@ GENERATE_TESTCASE(init_held_rsem)
 #include "locking-selftest-spin-hardirq.h"
 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_spin)
 
+#ifndef CONFIG_PREEMPT_RT_FULL
+
 #include "locking-selftest-rlock-hardirq.h"
 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_rlock)
 
@@ -605,9 +607,12 @@ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_rlock)
 #include "locking-selftest-wlock-softirq.h"
 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_wlock)
 
+#endif
+
 #undef E1
 #undef E2
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 /*
  * Enabling hardirqs with a softirq-safe lock held:
  */
@@ -640,6 +645,8 @@ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_rlock)
 #undef E1
 #undef E2
 
+#endif
+
 /*
  * Enabling irqs with an irq-safe lock held:
  */
@@ -663,6 +670,8 @@ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_rlock)
 #include "locking-selftest-spin-hardirq.h"
 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_spin)
 
+#ifndef CONFIG_PREEMPT_RT_FULL
+
 #include "locking-selftest-rlock-hardirq.h"
 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_rlock)
 
@@ -678,6 +687,8 @@ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_rlock)
 #include "locking-selftest-wlock-softirq.h"
 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_wlock)
 
+#endif
+
 #undef E1
 #undef E2
 
@@ -709,6 +720,8 @@ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_wlock)
 #include "locking-selftest-spin-hardirq.h"
 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_spin)
 
+#ifndef CONFIG_PREEMPT_RT_FULL
+
 #include "locking-selftest-rlock-hardirq.h"
 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_rlock)
 
@@ -724,6 +737,8 @@ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_rlock)
 #include "locking-selftest-wlock-softirq.h"
 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_wlock)
 
+#endif
+
 #undef E1
 #undef E2
 #undef E3
@@ -757,6 +772,8 @@ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_wlock)
 #include "locking-selftest-spin-hardirq.h"
 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_spin)
 
+#ifndef CONFIG_PREEMPT_RT_FULL
+
 #include "locking-selftest-rlock-hardirq.h"
 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_rlock)
 
@@ -772,10 +789,14 @@ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_rlock)
 #include "locking-selftest-wlock-softirq.h"
 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_wlock)
 
+#endif
+
 #undef E1
 #undef E2
 #undef E3
 
+#ifndef CONFIG_PREEMPT_RT_FULL
+
 /*
  * read-lock / write-lock irq inversion.
  *
@@ -838,6 +859,10 @@ GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_soft_wlock)
 #undef E2
 #undef E3
 
+#endif
+
+#ifndef CONFIG_PREEMPT_RT_FULL
+
 /*
  * read-lock / write-lock recursion that is actually safe.
  */
@@ -876,6 +901,8 @@ GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_soft)
 #undef E2
 #undef E3
 
+#endif
+
 /*
  * read-lock / write-lock recursion that is unsafe.
  */
@@ -1858,6 +1885,7 @@ void locking_selftest(void)
 
        printk("  --------------------------------------------------------------------------\n");
 
+#ifndef CONFIG_PREEMPT_RT_FULL
        /*
         * irq-context testcases:
         */
@@ -1870,6 +1898,28 @@ void locking_selftest(void)
 
        DO_TESTCASE_6x2("irq read-recursion", irq_read_recursion);
 //     DO_TESTCASE_6x2B("irq read-recursion #2", irq_read_recursion2);
+#else
+       /* On -rt, we only do hardirq context test for raw spinlock */
+       DO_TESTCASE_1B("hard-irqs-on + irq-safe-A", irqsafe1_hard_spin, 12);
+       DO_TESTCASE_1B("hard-irqs-on + irq-safe-A", irqsafe1_hard_spin, 21);
+
+       DO_TESTCASE_1B("hard-safe-A + irqs-on", irqsafe2B_hard_spin, 12);
+       DO_TESTCASE_1B("hard-safe-A + irqs-on", irqsafe2B_hard_spin, 21);
+
+       DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 123);
+       DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 132);
+       DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 213);
+       DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 231);
+       DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 312);
+       DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 321);
+
+       DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 123);
+       DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 132);
+       DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 213);
+       DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 231);
+       DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 312);
+       DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 321);
+#endif
 
        ww_tests();
 
index 6d40944..822a2c0 100644 (file)
@@ -26,6 +26,9 @@
 #include <linux/string.h>
 #include <linux/spinlock.h>
 #include <linux/percpu_ida.h>
+#include <linux/locallock.h>
+
+static DEFINE_LOCAL_IRQ_LOCK(irq_off_lock);
 
 struct percpu_ida_cpu {
        /*
@@ -148,13 +151,13 @@ int percpu_ida_alloc(struct percpu_ida *pool, int state)
        unsigned long flags;
        int tag;
 
-       local_irq_save(flags);
+       local_lock_irqsave(irq_off_lock, flags);
        tags = this_cpu_ptr(pool->tag_cpu);
 
        /* Fastpath */
        tag = alloc_local_tag(tags);
        if (likely(tag >= 0)) {
-               local_irq_restore(flags);
+               local_unlock_irqrestore(irq_off_lock, flags);
                return tag;
        }
 
@@ -173,6 +176,7 @@ int percpu_ida_alloc(struct percpu_ida *pool, int state)
 
                if (!tags->nr_free)
                        alloc_global_tags(pool, tags);
+
                if (!tags->nr_free)
                        steal_tags(pool, tags);
 
@@ -184,7 +188,7 @@ int percpu_ida_alloc(struct percpu_ida *pool, int state)
                }
 
                spin_unlock(&pool->lock);
-               local_irq_restore(flags);
+               local_unlock_irqrestore(irq_off_lock, flags);
 
                if (tag >= 0 || state == TASK_RUNNING)
                        break;
@@ -196,7 +200,7 @@ int percpu_ida_alloc(struct percpu_ida *pool, int state)
 
                schedule();
 
-               local_irq_save(flags);
+               local_lock_irqsave(irq_off_lock, flags);
                tags = this_cpu_ptr(pool->tag_cpu);
        }
        if (state != TASK_RUNNING)
@@ -221,7 +225,7 @@ void percpu_ida_free(struct percpu_ida *pool, unsigned tag)
 
        BUG_ON(tag >= pool->nr_tags);
 
-       local_irq_save(flags);
+       local_lock_irqsave(irq_off_lock, flags);
        tags = this_cpu_ptr(pool->tag_cpu);
 
        spin_lock(&tags->lock);
@@ -253,7 +257,7 @@ void percpu_ida_free(struct percpu_ida *pool, unsigned tag)
                spin_unlock(&pool->lock);
        }
 
-       local_irq_restore(flags);
+       local_unlock_irqrestore(irq_off_lock, flags);
 }
 EXPORT_SYMBOL_GPL(percpu_ida_free);
 
@@ -345,7 +349,7 @@ int percpu_ida_for_each_free(struct percpu_ida *pool, percpu_ida_cb fn,
        struct percpu_ida_cpu *remote;
        unsigned cpu, i, err = 0;
 
-       local_irq_save(flags);
+       local_lock_irqsave(irq_off_lock, flags);
        for_each_possible_cpu(cpu) {
                remote = per_cpu_ptr(pool->tag_cpu, cpu);
                spin_lock(&remote->lock);
@@ -367,7 +371,7 @@ int percpu_ida_for_each_free(struct percpu_ida *pool, percpu_ida_cb fn,
        }
        spin_unlock(&pool->lock);
 out:
-       local_irq_restore(flags);
+       local_unlock_irqrestore(irq_off_lock, flags);
        return err;
 }
 EXPORT_SYMBOL_GPL(percpu_ida_for_each_free);
index 8e6d552..741da5a 100644 (file)
@@ -36,7 +36,7 @@
 #include <linux/bitops.h>
 #include <linux/rcupdate.h>
 #include <linux/preempt.h>             /* in_interrupt() */
-
+#include <linux/locallock.h>
 
 /* Number of nodes in fully populated tree of given height */
 static unsigned long height_to_maxnodes[RADIX_TREE_MAX_PATH + 1] __read_mostly;
@@ -68,6 +68,7 @@ struct radix_tree_preload {
        struct radix_tree_node *nodes;
 };
 static DEFINE_PER_CPU(struct radix_tree_preload, radix_tree_preloads) = { 0, };
+static DEFINE_LOCAL_IRQ_LOCK(radix_tree_preloads_lock);
 
 static inline void *node_to_entry(void *ptr)
 {
@@ -290,13 +291,14 @@ radix_tree_node_alloc(struct radix_tree_root *root)
                 * succeed in getting a node here (and never reach
                 * kmem_cache_alloc)
                 */
-               rtp = this_cpu_ptr(&radix_tree_preloads);
+               rtp = &get_locked_var(radix_tree_preloads_lock, radix_tree_preloads);
                if (rtp->nr) {
                        ret = rtp->nodes;
                        rtp->nodes = ret->private_data;
                        ret->private_data = NULL;
                        rtp->nr--;
                }
+               put_locked_var(radix_tree_preloads_lock, radix_tree_preloads);
                /*
                 * Update the allocation stack trace as this is more useful
                 * for debugging.
@@ -357,14 +359,14 @@ static int __radix_tree_preload(gfp_t gfp_mask, int nr)
         */
        gfp_mask &= ~__GFP_ACCOUNT;
 
-       preempt_disable();
+       local_lock(radix_tree_preloads_lock);
        rtp = this_cpu_ptr(&radix_tree_preloads);
        while (rtp->nr < nr) {
-               preempt_enable();
+               local_unlock(radix_tree_preloads_lock);
                node = kmem_cache_alloc(radix_tree_node_cachep, gfp_mask);
                if (node == NULL)
                        goto out;
-               preempt_disable();
+               local_lock(radix_tree_preloads_lock);
                rtp = this_cpu_ptr(&radix_tree_preloads);
                if (rtp->nr < nr) {
                        node->private_data = rtp->nodes;
@@ -406,7 +408,7 @@ int radix_tree_maybe_preload(gfp_t gfp_mask)
        if (gfpflags_allow_blocking(gfp_mask))
                return __radix_tree_preload(gfp_mask, RADIX_TREE_PRELOAD_SIZE);
        /* Preloading doesn't help anything with this gfp mask, skip it */
-       preempt_disable();
+       local_lock(radix_tree_preloads_lock);
        return 0;
 }
 EXPORT_SYMBOL(radix_tree_maybe_preload);
@@ -422,7 +424,7 @@ int radix_tree_maybe_preload_order(gfp_t gfp_mask, int order)
 
        /* Preloading doesn't help anything with this gfp mask, skip it */
        if (!gfpflags_allow_blocking(gfp_mask)) {
-               preempt_disable();
+               local_lock(radix_tree_preloads_lock);
                return 0;
        }
 
@@ -456,6 +458,12 @@ int radix_tree_maybe_preload_order(gfp_t gfp_mask, int order)
        return __radix_tree_preload(gfp_mask, nr_nodes);
 }
 
+void radix_tree_preload_end(void)
+{
+       local_unlock(radix_tree_preloads_lock);
+}
+EXPORT_SYMBOL(radix_tree_preload_end);
+
 /*
  * The maximum index which can be stored in a radix tree
  */
index ef8c14a..fe638f9 100644 (file)
@@ -621,7 +621,7 @@ void sg_miter_stop(struct sg_mapping_iter *miter)
                        flush_kernel_dcache_page(miter->page);
 
                if (miter->__flags & SG_MITER_ATOMIC) {
-                       WARN_ON_ONCE(preemptible());
+                       WARN_ON_ONCE(!pagefault_disabled());
                        kunmap_atomic(miter->addr);
                } else
                        kunmap(miter->page);
@@ -665,7 +665,7 @@ size_t sg_copy_buffer(struct scatterlist *sgl, unsigned int nents, void *buf,
        if (!sg_miter_skip(&miter, skip))
                return false;
 
-       local_irq_save(flags);
+       local_irq_save_nort(flags);
 
        while (sg_miter_next(&miter) && offset < buflen) {
                unsigned int len;
@@ -682,7 +682,7 @@ size_t sg_copy_buffer(struct scatterlist *sgl, unsigned int nents, void *buf,
 
        sg_miter_stop(&miter);
 
-       local_irq_restore(flags);
+       local_irq_restore_nort(flags);
        return offset;
 }
 EXPORT_SYMBOL(sg_copy_buffer);
index 1afec32..11fa431 100644 (file)
@@ -39,8 +39,9 @@ notrace static unsigned int check_preemption_disabled(const char *what1,
        if (!printk_ratelimit())
                goto out_enable;
 
-       printk(KERN_ERR "BUG: using %s%s() in preemptible [%08x] code: %s/%d\n",
-               what1, what2, preempt_count() - 1, current->comm, current->pid);
+       printk(KERN_ERR "BUG: using %s%s() in preemptible [%08x %08x] code: %s/%d\n",
+               what1, what2, preempt_count() - 1, __migrate_disabled(current),
+               current->comm, current->pid);
 
        print_symbol("caller is %s\n", (long)__builtin_return_address(0));
        dump_stack();
diff --git a/localversion-rt b/localversion-rt
new file mode 100644 (file)
index 0000000..d17216d
--- /dev/null
@@ -0,0 +1 @@
+-rt156
index ea074a9..ef45be9 100644 (file)
@@ -410,7 +410,7 @@ config NOMMU_INITIAL_TRIM_EXCESS
 
 config TRANSPARENT_HUGEPAGE
        bool "Transparent Hugepage Support"
-       depends on HAVE_ARCH_TRANSPARENT_HUGEPAGE
+       depends on HAVE_ARCH_TRANSPARENT_HUGEPAGE && !PREEMPT_RT_FULL
        select COMPACTION
        select RADIX_TREE_MULTIORDER
        help
index 113b7d3..2f858ef 100644 (file)
@@ -457,9 +457,9 @@ void wb_congested_put(struct bdi_writeback_congested *congested)
 {
        unsigned long flags;
 
-       local_irq_save(flags);
+       local_irq_save_nort(flags);
        if (!atomic_dec_and_lock(&congested->refcnt, &cgwb_lock)) {
-               local_irq_restore(flags);
+               local_irq_restore_nort(flags);
                return;
        }
 
index 372b953..8a2abe6 100644 (file)
@@ -1746,10 +1746,12 @@ check_drain:
                                block_start_pfn(cc->migrate_pfn, cc->order);
 
                        if (cc->last_migrated_pfn < current_block_start) {
-                               cpu = get_cpu();
+                               cpu = get_cpu_light();
+                               local_lock_irq(swapvec_lock);
                                lru_add_drain_cpu(cpu);
+                               local_unlock_irq(swapvec_lock);
                                drain_local_pages(zone);
-                               put_cpu();
+                               put_cpu_light();
                                /* No more flushing until we migrate again */
                                cc->last_migrated_pfn = 0;
                        }
index 4ba171a..395da3d 100644 (file)
@@ -159,9 +159,12 @@ static int page_cache_tree_insert(struct address_space *mapping,
                 * node->private_list is protected by
                 * mapping->tree_lock.
                 */
-               if (!list_empty(&node->private_list))
-                       list_lru_del(&workingset_shadow_nodes,
+               if (!list_empty(&node->private_list)) {
+                       local_lock(workingset_shadow_lock);
+                       list_lru_del(&__workingset_shadow_nodes,
                                     &node->private_list);
+                       local_unlock(workingset_shadow_lock);
+               }
        }
        return 0;
 }
@@ -217,8 +220,10 @@ static void page_cache_tree_delete(struct address_space *mapping,
                if (!dax_mapping(mapping) && !workingset_node_pages(node) &&
                                list_empty(&node->private_list)) {
                        node->private_data = mapping;
-                       list_lru_add(&workingset_shadow_nodes,
-                                       &node->private_list);
+                       local_lock(workingset_shadow_lock);
+                       list_lru_add(&__workingset_shadow_nodes,
+                                    &node->private_list);
+                       local_unlock(workingset_shadow_lock);
                }
        }
 
index 50b4ca6..77518a3 100644 (file)
 #include <linux/kgdb.h>
 #include <asm/tlbflush.h>
 
-
+#ifndef CONFIG_PREEMPT_RT_FULL
 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32)
 DEFINE_PER_CPU(int, __kmap_atomic_idx);
 #endif
+#endif
 
 /*
  * Virtual_count is not a pure "count".
@@ -107,8 +108,9 @@ static inline wait_queue_head_t *get_pkmap_wait_queue_head(unsigned int color)
 unsigned long totalhigh_pages __read_mostly;
 EXPORT_SYMBOL(totalhigh_pages);
 
-
+#ifndef CONFIG_PREEMPT_RT_FULL
 EXPORT_PER_CPU_SYMBOL(__kmap_atomic_idx);
+#endif
 
 unsigned int nr_free_highpages (void)
 {
index d423274..c470339 100644 (file)
@@ -67,6 +67,7 @@
 #include <net/sock.h>
 #include <net/ip.h>
 #include "slab.h"
+#include <linux/locallock.h>
 
 #include <asm/uaccess.h>
 
@@ -92,6 +93,8 @@ int do_swap_account __read_mostly;
 #define do_swap_account                0
 #endif
 
+static DEFINE_LOCAL_IRQ_LOCK(event_lock);
+
 /* Whether legacy memory+swap accounting is active */
 static bool do_memsw_account(void)
 {
@@ -1814,7 +1817,7 @@ static void drain_all_stock(struct mem_cgroup *root_memcg)
                return;
        /* Notify other cpus that system-wide "drain" is running */
        get_online_cpus();
-       curcpu = get_cpu();
+       curcpu = get_cpu_light();
        for_each_online_cpu(cpu) {
                struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu);
                struct mem_cgroup *memcg;
@@ -1831,7 +1834,7 @@ static void drain_all_stock(struct mem_cgroup *root_memcg)
                                schedule_work_on(cpu, &stock->work);
                }
        }
-       put_cpu();
+       put_cpu_light();
        put_online_cpus();
        mutex_unlock(&percpu_charge_mutex);
 }
@@ -4600,12 +4603,12 @@ static int mem_cgroup_move_account(struct page *page,
 
        ret = 0;
 
-       local_irq_disable();
+       local_lock_irq(event_lock);
        mem_cgroup_charge_statistics(to, page, compound, nr_pages);
        memcg_check_events(to, page);
        mem_cgroup_charge_statistics(from, page, compound, -nr_pages);
        memcg_check_events(from, page);
-       local_irq_enable();
+       local_unlock_irq(event_lock);
 out_unlock:
        unlock_page(page);
 out:
@@ -5480,10 +5483,10 @@ void mem_cgroup_commit_charge(struct page *page, struct mem_cgroup *memcg,
 
        commit_charge(page, memcg, lrucare);
 
-       local_irq_disable();
+       local_lock_irq(event_lock);
        mem_cgroup_charge_statistics(memcg, page, compound, nr_pages);
        memcg_check_events(memcg, page);
-       local_irq_enable();
+       local_unlock_irq(event_lock);
 
        if (do_memsw_account() && PageSwapCache(page)) {
                swp_entry_t entry = { .val = page_private(page) };
@@ -5539,14 +5542,14 @@ static void uncharge_batch(struct mem_cgroup *memcg, unsigned long pgpgout,
                memcg_oom_recover(memcg);
        }
 
-       local_irq_save(flags);
+       local_lock_irqsave(event_lock, flags);
        __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_RSS], nr_anon);
        __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_CACHE], nr_file);
        __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_RSS_HUGE], nr_huge);
        __this_cpu_add(memcg->stat->events[MEM_CGROUP_EVENTS_PGPGOUT], pgpgout);
        __this_cpu_add(memcg->stat->nr_page_events, nr_pages);
        memcg_check_events(memcg, dummy_page);
-       local_irq_restore(flags);
+       local_unlock_irqrestore(event_lock, flags);
 
        if (!mem_cgroup_is_root(memcg))
                css_put_many(&memcg->css, nr_pages);
@@ -5701,10 +5704,10 @@ void mem_cgroup_migrate(struct page *oldpage, struct page *newpage)
 
        commit_charge(newpage, memcg, false);
 
-       local_irq_save(flags);
+       local_lock_irqsave(event_lock, flags);
        mem_cgroup_charge_statistics(memcg, newpage, compound, nr_pages);
        memcg_check_events(memcg, newpage);
-       local_irq_restore(flags);
+       local_unlock_irqrestore(event_lock, flags);
 }
 
 DEFINE_STATIC_KEY_FALSE(memcg_sockets_enabled_key);
@@ -5899,6 +5902,7 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
 {
        struct mem_cgroup *memcg, *swap_memcg;
        unsigned short oldid;
+       unsigned long flags;
 
        VM_BUG_ON_PAGE(PageLRU(page), page);
        VM_BUG_ON_PAGE(page_count(page), page);
@@ -5939,12 +5943,16 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
         * important here to have the interrupts disabled because it is the
         * only synchronisation we have for udpating the per-CPU variables.
         */
+       local_lock_irqsave(event_lock, flags);
+#ifndef CONFIG_PREEMPT_RT_BASE
        VM_BUG_ON(!irqs_disabled());
+#endif
        mem_cgroup_charge_statistics(memcg, page, false, -1);
        memcg_check_events(memcg, page);
 
        if (!mem_cgroup_is_root(memcg))
                css_put(&memcg->css);
+       local_unlock_irqrestore(event_lock, flags);
 }
 
 /*
index 6f4d27c..5cd25c7 100644 (file)
@@ -23,6 +23,7 @@ void use_mm(struct mm_struct *mm)
        struct task_struct *tsk = current;
 
        task_lock(tsk);
+       preempt_disable_rt();
        active_mm = tsk->active_mm;
        if (active_mm != mm) {
                atomic_inc(&mm->mm_count);
@@ -30,6 +31,7 @@ void use_mm(struct mm_struct *mm)
        }
        tsk->mm = mm;
        switch_mm(active_mm, mm, tsk);
+       preempt_enable_rt();
        task_unlock(tsk);
 #ifdef finish_arch_post_lock_switch
        finish_arch_post_lock_switch();
index f3c4221..973e741 100644 (file)
@@ -61,6 +61,7 @@
 #include <linux/page_ext.h>
 #include <linux/hugetlb.h>
 #include <linux/sched/rt.h>
+#include <linux/locallock.h>
 #include <linux/page_owner.h>
 #include <linux/kthread.h>
 #include <linux/memcontrol.h>
@@ -297,6 +298,18 @@ EXPORT_SYMBOL(nr_node_ids);
 EXPORT_SYMBOL(nr_online_nodes);
 #endif
 
+static DEFINE_LOCAL_IRQ_LOCK(pa_lock);
+
+#ifdef CONFIG_PREEMPT_RT_BASE
+# define cpu_lock_irqsave(cpu, flags)          \
+       local_lock_irqsave_on(pa_lock, flags, cpu)
+# define cpu_unlock_irqrestore(cpu, flags)     \
+       local_unlock_irqrestore_on(pa_lock, flags, cpu)
+#else
+# define cpu_lock_irqsave(cpu, flags)          local_irq_save(flags)
+# define cpu_unlock_irqrestore(cpu, flags)     local_irq_restore(flags)
+#endif
+
 int page_group_by_mobility_disabled __read_mostly;
 
 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
@@ -1143,7 +1156,7 @@ static bool bulkfree_pcp_prepare(struct page *page)
 #endif /* CONFIG_DEBUG_VM */
 
 /*
- * Frees a number of pages from the PCP lists
+ * Frees a number of pages which have been collected from the pcp lists.
  * Assumes all pages on list are in same zone, and of same order.
  * count is the number of pages to free.
  *
@@ -1154,24 +1167,58 @@ static bool bulkfree_pcp_prepare(struct page *page)
  * pinned" detection logic.
  */
 static void free_pcppages_bulk(struct zone *zone, int count,
-                                       struct per_cpu_pages *pcp)
+                              struct list_head *list)
 {
-       int migratetype = 0;
-       int batch_free = 0;
        unsigned long nr_scanned;
        bool isolated_pageblocks;
+       unsigned long flags;
+
+       spin_lock_irqsave(&zone->lock, flags);
 
-       spin_lock(&zone->lock);
        isolated_pageblocks = has_isolate_pageblock(zone);
        nr_scanned = node_page_state(zone->zone_pgdat, NR_PAGES_SCANNED);
        if (nr_scanned)
                __mod_node_page_state(zone->zone_pgdat, NR_PAGES_SCANNED, -nr_scanned);
 
-       /*
-        * Ensure proper count is passed which otherwise would stuck in the
-        * below while (list_empty(list)) loop.
-        */
-       count = min(pcp->count, count);
+       while (!list_empty(list)) {
+               struct page *page;
+               int mt; /* migratetype of the to-be-freed page */
+
+               page = list_first_entry(list, struct page, lru);
+               /* must delete as __free_one_page list manipulates */
+               list_del(&page->lru);
+
+               mt = get_pcppage_migratetype(page);
+               /* MIGRATE_ISOLATE page should not go to pcplists */
+               VM_BUG_ON_PAGE(is_migrate_isolate(mt), page);
+               /* Pageblock could have been isolated meanwhile */
+               if (unlikely(isolated_pageblocks))
+                       mt = get_pageblock_migratetype(page);
+
+               if (bulkfree_pcp_prepare(page))
+                       continue;
+
+               __free_one_page(page, page_to_pfn(page), zone, 0, mt);
+               trace_mm_page_pcpu_drain(page, 0, mt);
+               count--;
+       }
+       WARN_ON(count != 0);
+       spin_unlock_irqrestore(&zone->lock, flags);
+}
+
+/*
+ * Moves a number of pages from the PCP lists to free list which
+ * is freed outside of the locked region.
+ *
+ * Assumes all pages on list are in same zone, and of same order.
+ * count is the number of pages to free.
+ */
+static void isolate_pcp_pages(int count, struct per_cpu_pages *src,
+                             struct list_head *dst)
+{
+       int migratetype = 0;
+       int batch_free = 0;
+
        while (count) {
                struct page *page;
                struct list_head *list;
@@ -1187,7 +1234,7 @@ static void free_pcppages_bulk(struct zone *zone, int count,
                        batch_free++;
                        if (++migratetype == MIGRATE_PCPTYPES)
                                migratetype = 0;
-                       list = &pcp->lists[migratetype];
+                       list = &src->lists[migratetype];
                } while (list_empty(list));
 
                /* This is the only non-empty list. Free them all. */
@@ -1195,27 +1242,12 @@ static void free_pcppages_bulk(struct zone *zone, int count,
                        batch_free = count;
 
                do {
-                       int mt; /* migratetype of the to-be-freed page */
-
                        page = list_last_entry(list, struct page, lru);
-                       /* must delete as __free_one_page list manipulates */
                        list_del(&page->lru);
 
-                       mt = get_pcppage_migratetype(page);
-                       /* MIGRATE_ISOLATE page should not go to pcplists */
-                       VM_BUG_ON_PAGE(is_migrate_isolate(mt), page);
-                       /* Pageblock could have been isolated meanwhile */
-                       if (unlikely(isolated_pageblocks))
-                               mt = get_pageblock_migratetype(page);
-
-                       if (bulkfree_pcp_prepare(page))
-                               continue;
-
-                       __free_one_page(page, page_to_pfn(page), zone, 0, mt);
-                       trace_mm_page_pcpu_drain(page, 0, mt);
+                       list_add(&page->lru, dst);
                } while (--count && --batch_free && !list_empty(list));
        }
-       spin_unlock(&zone->lock);
 }
 
 static void free_one_page(struct zone *zone,
@@ -1224,7 +1256,9 @@ static void free_one_page(struct zone *zone,
                                int migratetype)
 {
        unsigned long nr_scanned;
-       spin_lock(&zone->lock);
+       unsigned long flags;
+
+       spin_lock_irqsave(&zone->lock, flags);
        nr_scanned = node_page_state(zone->zone_pgdat, NR_PAGES_SCANNED);
        if (nr_scanned)
                __mod_node_page_state(zone->zone_pgdat, NR_PAGES_SCANNED, -nr_scanned);
@@ -1234,7 +1268,7 @@ static void free_one_page(struct zone *zone,
                migratetype = get_pfnblock_migratetype(page, pfn);
        }
        __free_one_page(page, pfn, zone, order, migratetype);
-       spin_unlock(&zone->lock);
+       spin_unlock_irqrestore(&zone->lock, flags);
 }
 
 static void __meminit __init_single_page(struct page *page, unsigned long pfn,
@@ -1320,10 +1354,10 @@ static void __free_pages_ok(struct page *page, unsigned int order)
                return;
 
        migratetype = get_pfnblock_migratetype(page, pfn);
-       local_irq_save(flags);
+       local_lock_irqsave(pa_lock, flags);
        __count_vm_events(PGFREE, 1 << order);
        free_one_page(page_zone(page), page, pfn, order, migratetype);
-       local_irq_restore(flags);
+       local_unlock_irqrestore(pa_lock, flags);
 }
 
 static void __init __free_pages_boot_core(struct page *page, unsigned int order)
@@ -2431,16 +2465,18 @@ static int rmqueue_bulk(struct zone *zone, unsigned int order,
 void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp)
 {
        unsigned long flags;
+       LIST_HEAD(dst);
        int to_drain, batch;
 
-       local_irq_save(flags);
+       local_lock_irqsave(pa_lock, flags);
        batch = READ_ONCE(pcp->batch);
        to_drain = min(pcp->count, batch);
        if (to_drain > 0) {
-               free_pcppages_bulk(zone, to_drain, pcp);
+               isolate_pcp_pages(to_drain, pcp, &dst);
                pcp->count -= to_drain;
        }
-       local_irq_restore(flags);
+       local_unlock_irqrestore(pa_lock, flags);
+       free_pcppages_bulk(zone, to_drain, &dst);
 }
 #endif
 
@@ -2456,16 +2492,21 @@ static void drain_pages_zone(unsigned int cpu, struct zone *zone)
        unsigned long flags;
        struct per_cpu_pageset *pset;
        struct per_cpu_pages *pcp;
+       LIST_HEAD(dst);
+       int count;
 
-       local_irq_save(flags);
+       cpu_lock_irqsave(cpu, flags);
        pset = per_cpu_ptr(zone->pageset, cpu);
 
        pcp = &pset->pcp;
-       if (pcp->count) {
-               free_pcppages_bulk(zone, pcp->count, pcp);
+       count = pcp->count;
+       if (count) {
+               isolate_pcp_pages(count, pcp, &dst);
                pcp->count = 0;
        }
-       local_irq_restore(flags);
+       cpu_unlock_irqrestore(cpu, flags);
+       if (count)
+               free_pcppages_bulk(zone, count, &dst);
 }
 
 /*
@@ -2552,7 +2593,16 @@ void drain_all_pages(struct zone *zone)
                else
                        cpumask_clear_cpu(cpu, &cpus_with_pcps);
        }
+#ifndef CONFIG_PREEMPT_RT_BASE
        on_each_cpu_mask(&cpus_with_pcps, drain_local_pages, zone, 1);
+#else
+       for_each_cpu(cpu, &cpus_with_pcps) {
+               if (zone)
+                       drain_pages_zone(cpu, zone);
+               else
+                       drain_pages(cpu);
+       }
+#endif
 }
 
 #ifdef CONFIG_HIBERNATION
@@ -2612,7 +2662,7 @@ void free_hot_cold_page(struct page *page, bool cold)
 
        migratetype = get_pfnblock_migratetype(page, pfn);
        set_pcppage_migratetype(page, migratetype);
-       local_irq_save(flags);
+       local_lock_irqsave(pa_lock, flags);
        __count_vm_event(PGFREE);
 
        /*
@@ -2655,12 +2705,17 @@ void free_hot_cold_page(struct page *page, bool cold)
        pcp->count++;
        if (pcp->count >= pcp->high) {
                unsigned long batch = READ_ONCE(pcp->batch);
-               free_pcppages_bulk(zone, batch, pcp);
+               LIST_HEAD(dst);
+
+               isolate_pcp_pages(batch, pcp, &dst);
                pcp->count -= batch;
+               local_unlock_irqrestore(pa_lock, flags);
+               free_pcppages_bulk(zone, batch, &dst);
+               return;
        }
 
 out:
-       local_irq_restore(flags);
+       local_unlock_irqrestore(pa_lock, flags);
 }
 
 /*
@@ -2802,7 +2857,7 @@ struct page *buffered_rmqueue(struct zone *preferred_zone,
                struct per_cpu_pages *pcp;
                struct list_head *list;
 
-               local_irq_save(flags);
+               local_lock_irqsave(pa_lock, flags);
                do {
                        pcp = &this_cpu_ptr(zone->pageset)->pcp;
                        list = &pcp->lists[migratetype];
@@ -2875,7 +2930,7 @@ use_pcp:
                 * allocate greater than order-1 page units with __GFP_NOFAIL.
                 */
                WARN_ON_ONCE((gfp_flags & __GFP_NOFAIL) && (order > 1));
-               spin_lock_irqsave(&zone->lock, flags);
+               local_spin_lock_irqsave(pa_lock, &zone->lock, flags);
 
                do {
                        page = NULL;
@@ -2892,11 +2947,13 @@ use_pcp:
                                page = __rmqueue(zone, order, migratetype);
                        #endif /* CONFIG_AMLOGIC_CMA */
                } while (page && check_new_pages(page, order));
-               spin_unlock(&zone->lock);
-               if (!page)
+               if (!page) {
+                       spin_unlock(&zone->lock);
                        goto failed;
+               }
                __mod_zone_freepage_state(zone, -(1 << order),
                                          get_pcppage_migratetype(page));
+               spin_unlock(&zone->lock);
        }
 
 #ifdef CONFIG_AMLOGIC_CMA
@@ -2904,13 +2961,13 @@ alloc_success:
 #endif /* CONFIG_AMLOGIC_CMA */
        __count_zid_vm_events(PGALLOC, page_zonenum(page), 1 << order);
        zone_statistics(preferred_zone, zone, gfp_flags);
-       local_irq_restore(flags);
+       local_unlock_irqrestore(pa_lock, flags);
 
        VM_BUG_ON_PAGE(bad_range(zone, page), page);
        return page;
 
 failed:
-       local_irq_restore(flags);
+       local_unlock_irqrestore(pa_lock, flags);
        return NULL;
 }
 
@@ -6870,7 +6927,9 @@ static int page_alloc_cpu_notify(struct notifier_block *self,
        int cpu = (unsigned long)hcpu;
 
        if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) {
+               local_lock_irq_on(swapvec_lock, cpu);
                lru_add_drain_cpu(cpu);
+               local_unlock_irq_on(swapvec_lock, cpu);
                drain_pages(cpu);
 
                /*
@@ -6896,6 +6955,7 @@ static int page_alloc_cpu_notify(struct notifier_block *self,
 void __init page_alloc_init(void)
 {
        hotcpu_notifier(page_alloc_cpu_notify, 0);
+       local_irq_lock_init(pa_lock);
 }
 
 /*
@@ -7739,7 +7799,7 @@ void zone_pcp_reset(struct zone *zone)
        struct per_cpu_pageset *pset;
 
        /* avoid races with drain_pages()  */
-       local_irq_save(flags);
+       local_lock_irqsave(pa_lock, flags);
        if (zone->pageset != &boot_pageset) {
                for_each_online_cpu(cpu) {
                        pset = per_cpu_ptr(zone->pageset, cpu);
@@ -7748,7 +7808,7 @@ void zone_pcp_reset(struct zone *zone)
                free_percpu(zone->pageset);
                zone->pageset = &boot_pageset;
        }
-       local_irq_restore(flags);
+       local_unlock_irqrestore(pa_lock, flags);
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
index 0462a2a..39b3298 100644 (file)
@@ -1284,18 +1284,7 @@ void free_percpu(void __percpu *ptr)
 }
 EXPORT_SYMBOL_GPL(free_percpu);
 
-/**
- * is_kernel_percpu_address - test whether address is from static percpu area
- * @addr: address to test
- *
- * Test whether @addr belongs to in-kernel static percpu area.  Module
- * static percpu areas are not considered.  For those, use
- * is_module_percpu_address().
- *
- * RETURNS:
- * %true if @addr is from in-kernel static percpu area, %false otherwise.
- */
-bool is_kernel_percpu_address(unsigned long addr)
+bool __is_kernel_percpu_address(unsigned long addr, unsigned long *can_addr)
 {
 #ifdef CONFIG_SMP
        const size_t static_size = __per_cpu_end - __per_cpu_start;
@@ -1304,16 +1293,39 @@ bool is_kernel_percpu_address(unsigned long addr)
 
        for_each_possible_cpu(cpu) {
                void *start = per_cpu_ptr(base, cpu);
+               void *va = (void *)addr;
 
-               if ((void *)addr >= start && (void *)addr < start + static_size)
+               if (va >= start && va < start + static_size) {
+                       if (can_addr) {
+                               *can_addr = (unsigned long) (va - start);
+                               *can_addr += (unsigned long)
+                                       per_cpu_ptr(base, get_boot_cpu_id());
+                       }
                        return true;
-        }
+               }
+       }
 #endif
        /* on UP, can't distinguish from other static vars, always false */
        return false;
 }
 
 /**
+ * is_kernel_percpu_address - test whether address is from static percpu area
+ * @addr: address to test
+ *
+ * Test whether @addr belongs to in-kernel static percpu area.  Module
+ * static percpu areas are not considered.  For those, use
+ * is_module_percpu_address().
+ *
+ * RETURNS:
+ * %true if @addr is from in-kernel static percpu area, %false otherwise.
+ */
+bool is_kernel_percpu_address(unsigned long addr)
+{
+       return __is_kernel_percpu_address(addr, NULL);
+}
+
+/**
  * per_cpu_ptr_to_phys - convert translated percpu address to physical address
  * @addr: the address to be converted to physical address
  *
index ceb7d70..dfd281e 100644 (file)
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -426,7 +426,11 @@ static inline void slab_post_alloc_hook(struct kmem_cache *s, gfp_t flags,
  * The slab lists for all objects.
  */
 struct kmem_cache_node {
+#ifdef CONFIG_SLUB
+       raw_spinlock_t list_lock;
+#else
        spinlock_t list_lock;
+#endif
 
 #ifdef CONFIG_SLAB
        struct list_head slabs_partial; /* partial list first, better asm code */
index eb00e15..0f9bb3d 100644 (file)
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1158,7 +1158,7 @@ static noinline int free_debug_processing(
        unsigned long uninitialized_var(flags);
        int ret = 0;
 
-       spin_lock_irqsave(&n->list_lock, flags);
+       raw_spin_lock_irqsave(&n->list_lock, flags);
        slab_lock(page);
 
        if (s->flags & SLAB_CONSISTENCY_CHECKS) {
@@ -1193,7 +1193,7 @@ out:
                         bulk_cnt, cnt);
 
        slab_unlock(page);
-       spin_unlock_irqrestore(&n->list_lock, flags);
+       raw_spin_unlock_irqrestore(&n->list_lock, flags);
        if (!ret)
                slab_fix(s, "Object at 0x%p not freed", object);
        return ret;
@@ -1326,6 +1326,12 @@ static bool freelist_corrupted(struct kmem_cache *s, struct page *page,
 }
 #endif /* CONFIG_SLUB_DEBUG */
 
+struct slub_free_list {
+       raw_spinlock_t          lock;
+       struct list_head        list;
+};
+static DEFINE_PER_CPU(struct slub_free_list, slub_free_list);
+
 /*
  * Hooks for other subsystems that check memory allocations. In a typical
  * production configuration these hooks all should produce no code at all.
@@ -1552,10 +1558,17 @@ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)
        void *start, *p;
        int idx, order;
        bool shuffle;
+       bool enableirqs = false;
 
        flags &= gfp_allowed_mask;
 
        if (gfpflags_allow_blocking(flags))
+               enableirqs = true;
+#ifdef CONFIG_PREEMPT_RT_FULL
+       if (system_state == SYSTEM_RUNNING)
+               enableirqs = true;
+#endif
+       if (enableirqs)
                local_irq_enable();
 
        flags |= s->allocflags;
@@ -1630,7 +1643,7 @@ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)
        page->frozen = 1;
 
 out:
-       if (gfpflags_allow_blocking(flags))
+       if (enableirqs)
                local_irq_disable();
        if (!page)
                return NULL;
@@ -1692,6 +1705,16 @@ static void __free_slab(struct kmem_cache *s, struct page *page)
        __free_pages(page, order);
 }
 
+static void free_delayed(struct list_head *h)
+{
+       while(!list_empty(h)) {
+               struct page *page = list_first_entry(h, struct page, lru);
+
+               list_del(&page->lru);
+               __free_slab(page->slab_cache, page);
+       }
+}
+
 #define need_reserve_slab_rcu                                          \
        (sizeof(((struct page *)NULL)->lru) < sizeof(struct rcu_head))
 
@@ -1723,6 +1746,12 @@ static void free_slab(struct kmem_cache *s, struct page *page)
                }
 
                call_rcu(head, rcu_free_slab);
+       } else if (irqs_disabled()) {
+               struct slub_free_list *f = this_cpu_ptr(&slub_free_list);
+
+               raw_spin_lock(&f->lock);
+               list_add(&page->lru, &f->list);
+               raw_spin_unlock(&f->lock);
        } else
                __free_slab(s, page);
 }
@@ -1830,7 +1859,7 @@ static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n,
        if (!n || !n->nr_partial)
                return NULL;
 
-       spin_lock(&n->list_lock);
+       raw_spin_lock(&n->list_lock);
        list_for_each_entry_safe(page, page2, &n->partial, lru) {
                void *t;
 
@@ -1855,7 +1884,7 @@ static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n,
                        break;
 
        }
-       spin_unlock(&n->list_lock);
+       raw_spin_unlock(&n->list_lock);
        return object;
 }
 
@@ -2107,7 +2136,7 @@ redo:
                         * that acquire_slab() will see a slab page that
                         * is frozen
                         */
-                       spin_lock(&n->list_lock);
+                       raw_spin_lock(&n->list_lock);
                }
        } else {
                m = M_FULL;
@@ -2118,7 +2147,7 @@ redo:
                         * slabs from diagnostic functions will not see
                         * any frozen slabs.
                         */
-                       spin_lock(&n->list_lock);
+                       raw_spin_lock(&n->list_lock);
                }
        }
 
@@ -2153,7 +2182,7 @@ redo:
                goto redo;
 
        if (lock)
-               spin_unlock(&n->list_lock);
+               raw_spin_unlock(&n->list_lock);
 
        if (m == M_FREE) {
                stat(s, DEACTIVATE_EMPTY);
@@ -2185,10 +2214,10 @@ static void unfreeze_partials(struct kmem_cache *s,
                n2 = get_node(s, page_to_nid(page));
                if (n != n2) {
                        if (n)
-                               spin_unlock(&n->list_lock);
+                               raw_spin_unlock(&n->list_lock);
 
                        n = n2;
-                       spin_lock(&n->list_lock);
+                       raw_spin_lock(&n->list_lock);
                }
 
                do {
@@ -2217,7 +2246,7 @@ static void unfreeze_partials(struct kmem_cache *s,
        }
 
        if (n)
-               spin_unlock(&n->list_lock);
+               raw_spin_unlock(&n->list_lock);
 
        while (discard_page) {
                page = discard_page;
@@ -2256,14 +2285,21 @@ static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain)
                        pobjects = oldpage->pobjects;
                        pages = oldpage->pages;
                        if (drain && pobjects > s->cpu_partial) {
+                               struct slub_free_list *f;
                                unsigned long flags;
+                               LIST_HEAD(tofree);
                                /*
                                 * partial array is full. Move the existing
                                 * set to the per node partial list.
                                 */
                                local_irq_save(flags);
                                unfreeze_partials(s, this_cpu_ptr(s->cpu_slab));
+                               f = this_cpu_ptr(&slub_free_list);
+                               raw_spin_lock(&f->lock);
+                               list_splice_init(&f->list, &tofree);
+                               raw_spin_unlock(&f->lock);
                                local_irq_restore(flags);
+                               free_delayed(&tofree);
                                oldpage = NULL;
                                pobjects = 0;
                                pages = 0;
@@ -2335,7 +2371,22 @@ static bool has_cpu_slab(int cpu, void *info)
 
 static void flush_all(struct kmem_cache *s)
 {
+       LIST_HEAD(tofree);
+       int cpu;
+
        on_each_cpu_cond(has_cpu_slab, flush_cpu_slab, s, 1, GFP_ATOMIC);
+       for_each_online_cpu(cpu) {
+               struct slub_free_list *f;
+
+               if (!has_cpu_slab(cpu, s))
+                       continue;
+
+               f = &per_cpu(slub_free_list, cpu);
+               raw_spin_lock_irq(&f->lock);
+               list_splice_init(&f->list, &tofree);
+               raw_spin_unlock_irq(&f->lock);
+               free_delayed(&tofree);
+       }
 }
 
 /*
@@ -2390,10 +2441,10 @@ static unsigned long count_partial(struct kmem_cache_node *n,
        unsigned long x = 0;
        struct page *page;
 
-       spin_lock_irqsave(&n->list_lock, flags);
+       raw_spin_lock_irqsave(&n->list_lock, flags);
        list_for_each_entry(page, &n->partial, lru)
                x += get_count(page);
-       spin_unlock_irqrestore(&n->list_lock, flags);
+       raw_spin_unlock_irqrestore(&n->list_lock, flags);
        return x;
 }
 #endif /* CONFIG_SLUB_DEBUG || CONFIG_SYSFS */
@@ -2531,8 +2582,10 @@ static inline void *get_freelist(struct kmem_cache *s, struct page *page)
  * already disabled (which is the case for bulk allocation).
  */
 static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
-                         unsigned long addr, struct kmem_cache_cpu *c)
+                         unsigned long addr, struct kmem_cache_cpu *c,
+                         struct list_head *to_free)
 {
+       struct slub_free_list *f;
        void *freelist;
        struct page *page;
 
@@ -2605,6 +2658,13 @@ load_freelist:
 #ifdef CONFIG_AMLOGIC_SLAB_TRACE
        slab_trace_mark_object(freelist, addr, s);
 #endif
+
+out:
+       f = this_cpu_ptr(&slub_free_list);
+       raw_spin_lock(&f->lock);
+       list_splice_init(&f->list, to_free);
+       raw_spin_unlock(&f->lock);
+
        return freelist;
 
 new_slab:
@@ -2639,7 +2699,7 @@ new_slab:
 #ifdef CONFIG_AMLOGIC_SLAB_TRACE
        slab_trace_mark_object(freelist, addr, s);
 #endif
-       return freelist;
+       goto out;
 }
 
 /*
@@ -2651,6 +2711,7 @@ static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
 {
        void *p;
        unsigned long flags;
+       LIST_HEAD(tofree);
 
        local_irq_save(flags);
 #ifdef CONFIG_PREEMPT
@@ -2662,8 +2723,9 @@ static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
        c = this_cpu_ptr(s->cpu_slab);
 #endif
 
-       p = ___slab_alloc(s, gfpflags, node, addr, c);
+       p = ___slab_alloc(s, gfpflags, node, addr, c, &tofree);
        local_irq_restore(flags);
+       free_delayed(&tofree);
        return p;
 }
 
@@ -2852,7 +2914,7 @@ static void __slab_free(struct kmem_cache *s, struct page *page,
 
        do {
                if (unlikely(n)) {
-                       spin_unlock_irqrestore(&n->list_lock, flags);
+                       raw_spin_unlock_irqrestore(&n->list_lock, flags);
                        n = NULL;
                }
                prior = page->freelist;
@@ -2884,7 +2946,7 @@ static void __slab_free(struct kmem_cache *s, struct page *page,
                                 * Otherwise the list_lock will synchronize with
                                 * other processors updating the list of slabs.
                                 */
-                               spin_lock_irqsave(&n->list_lock, flags);
+                               raw_spin_lock_irqsave(&n->list_lock, flags);
 
                        }
                }
@@ -2926,7 +2988,7 @@ static void __slab_free(struct kmem_cache *s, struct page *page,
                add_partial(n, page, DEACTIVATE_TO_TAIL);
                stat(s, FREE_ADD_PARTIAL);
        }
-       spin_unlock_irqrestore(&n->list_lock, flags);
+       raw_spin_unlock_irqrestore(&n->list_lock, flags);
        return;
 
 slab_empty:
@@ -2941,7 +3003,7 @@ slab_empty:
                remove_full(s, n, page);
        }
 
-       spin_unlock_irqrestore(&n->list_lock, flags);
+       raw_spin_unlock_irqrestore(&n->list_lock, flags);
        stat(s, FREE_SLAB);
        discard_slab(s, page);
 }
@@ -3154,6 +3216,7 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size,
                          void **p)
 {
        struct kmem_cache_cpu *c;
+       LIST_HEAD(to_free);
        int i;
 
        /* memcg and kmem_cache debug support */
@@ -3186,7 +3249,7 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size,
                         * of re-populating per CPU c->freelist
                         */
                        p[i] = ___slab_alloc(s, flags, NUMA_NO_NODE,
-                                           _RET_IP_, c);
+                                           _RET_IP_, c, &to_free);
                        if (unlikely(!p[i]))
                                goto error;
 
@@ -3198,6 +3261,7 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size,
        }
        c->tid = next_tid(c->tid);
        local_irq_enable();
+       free_delayed(&to_free);
 
        /* Clear memory outside IRQ disabled fastpath loop */
        if (unlikely(flags & __GFP_ZERO)) {
@@ -3212,6 +3276,7 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size,
        return i;
 error:
        local_irq_enable();
+       free_delayed(&to_free);
        slab_post_alloc_hook(s, flags, i, p);
        __kmem_cache_free_bulk(s, i, p);
        return 0;
@@ -3345,7 +3410,7 @@ static void
 init_kmem_cache_node(struct kmem_cache_node *n)
 {
        n->nr_partial = 0;
-       spin_lock_init(&n->list_lock);
+       raw_spin_lock_init(&n->list_lock);
        INIT_LIST_HEAD(&n->partial);
 #ifdef CONFIG_SLUB_DEBUG
        atomic_long_set(&n->nr_slabs, 0);
@@ -3696,6 +3761,10 @@ static void list_slab_objects(struct kmem_cache *s, struct page *page,
                                                        const char *text)
 {
 #ifdef CONFIG_SLUB_DEBUG
+#ifdef CONFIG_PREEMPT_RT_BASE
+       /* XXX move out of irq-off section */
+       slab_err(s, page, text, s->name);
+#else
        void *addr = page_address(page);
        void *p;
        unsigned long *map = kzalloc(BITS_TO_LONGS(page->objects) *
@@ -3716,6 +3785,7 @@ static void list_slab_objects(struct kmem_cache *s, struct page *page,
        slab_unlock(page);
        kfree(map);
 #endif
+#endif
 }
 
 /*
@@ -3729,7 +3799,7 @@ static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n)
        struct page *page, *h;
 
        BUG_ON(irqs_disabled());
-       spin_lock_irq(&n->list_lock);
+       raw_spin_lock_irq(&n->list_lock);
        list_for_each_entry_safe(page, h, &n->partial, lru) {
                if (!page->inuse) {
                        remove_partial(n, page);
@@ -3739,7 +3809,7 @@ static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n)
                        "Objects remaining in %s on __kmem_cache_shutdown()");
                }
        }
-       spin_unlock_irq(&n->list_lock);
+       raw_spin_unlock_irq(&n->list_lock);
 
        list_for_each_entry_safe(page, h, &discard, lru)
                discard_slab(s, page);
@@ -4022,7 +4092,7 @@ int __kmem_cache_shrink(struct kmem_cache *s)
                for (i = 0; i < SHRINK_PROMOTE_MAX; i++)
                        INIT_LIST_HEAD(promote + i);
 
-               spin_lock_irqsave(&n->list_lock, flags);
+               raw_spin_lock_irqsave(&n->list_lock, flags);
 
                /*
                 * Build lists of slabs to discard or promote.
@@ -4053,7 +4123,7 @@ int __kmem_cache_shrink(struct kmem_cache *s)
                for (i = SHRINK_PROMOTE_MAX - 1; i >= 0; i--)
                        list_splice(promote + i, &n->partial);
 
-               spin_unlock_irqrestore(&n->list_lock, flags);
+               raw_spin_unlock_irqrestore(&n->list_lock, flags);
 
                /* Release empty slabs */
                list_for_each_entry_safe(page, t, &discard, lru)
@@ -4229,6 +4299,12 @@ void __init kmem_cache_init(void)
 {
        static __initdata struct kmem_cache boot_kmem_cache,
                boot_kmem_cache_node;
+       int cpu;
+
+       for_each_possible_cpu(cpu) {
+               raw_spin_lock_init(&per_cpu(slub_free_list, cpu).lock);
+               INIT_LIST_HEAD(&per_cpu(slub_free_list, cpu).list);
+       }
 
        if (debug_guardpage_minorder())
                slub_max_order = 0;
@@ -4440,7 +4516,7 @@ static int validate_slab_node(struct kmem_cache *s,
        struct page *page;
        unsigned long flags;
 
-       spin_lock_irqsave(&n->list_lock, flags);
+       raw_spin_lock_irqsave(&n->list_lock, flags);
 
        list_for_each_entry(page, &n->partial, lru) {
                validate_slab_slab(s, page, map);
@@ -4462,7 +4538,7 @@ static int validate_slab_node(struct kmem_cache *s,
                       s->name, count, atomic_long_read(&n->nr_slabs));
 
 out:
-       spin_unlock_irqrestore(&n->list_lock, flags);
+       raw_spin_unlock_irqrestore(&n->list_lock, flags);
        return count;
 }
 
@@ -4650,12 +4726,12 @@ static int list_locations(struct kmem_cache *s, char *buf,
                if (!atomic_long_read(&n->nr_slabs))
                        continue;
 
-               spin_lock_irqsave(&n->list_lock, flags);
+               raw_spin_lock_irqsave(&n->list_lock, flags);
                list_for_each_entry(page, &n->partial, lru)
                        process_slab(&t, s, page, alloc, map);
                list_for_each_entry(page, &n->full, lru)
                        process_slab(&t, s, page, alloc, map);
-               spin_unlock_irqrestore(&n->list_lock, flags);
+               raw_spin_unlock_irqrestore(&n->list_lock, flags);
        }
 
        for (i = 0; i < t.count; i++) {
index 4dcf852..69c3a5b 100644 (file)
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -32,6 +32,7 @@
 #include <linux/memcontrol.h>
 #include <linux/gfp.h>
 #include <linux/uio.h>
+#include <linux/locallock.h>
 #include <linux/hugetlb.h>
 #include <linux/page_idle.h>
 
@@ -50,6 +51,8 @@ static DEFINE_PER_CPU(struct pagevec, lru_deactivate_pvecs);
 #ifdef CONFIG_SMP
 static DEFINE_PER_CPU(struct pagevec, activate_page_pvecs);
 #endif
+static DEFINE_LOCAL_IRQ_LOCK(rotate_lock);
+DEFINE_LOCAL_IRQ_LOCK(swapvec_lock);
 
 /*
  * This path almost never happens for VM activity - pages are normally
@@ -240,11 +243,11 @@ void rotate_reclaimable_page(struct page *page)
                unsigned long flags;
 
                get_page(page);
-               local_irq_save(flags);
+               local_lock_irqsave(rotate_lock, flags);
                pvec = this_cpu_ptr(&lru_rotate_pvecs);
                if (!pagevec_add(pvec, page) || PageCompound(page))
                        pagevec_move_tail(pvec);
-               local_irq_restore(flags);
+               local_unlock_irqrestore(rotate_lock, flags);
        }
 }
 
@@ -294,12 +297,13 @@ void activate_page(struct page *page)
 {
        page = compound_head(page);
        if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) {
-               struct pagevec *pvec = &get_cpu_var(activate_page_pvecs);
+               struct pagevec *pvec = &get_locked_var(swapvec_lock,
+                                                      activate_page_pvecs);
 
                get_page(page);
                if (!pagevec_add(pvec, page) || PageCompound(page))
                        pagevec_lru_move_fn(pvec, __activate_page, NULL);
-               put_cpu_var(activate_page_pvecs);
+               put_locked_var(swapvec_lock, activate_page_pvecs);
        }
 }
 
@@ -326,7 +330,7 @@ void activate_page(struct page *page)
 
 static void __lru_cache_activate_page(struct page *page)
 {
-       struct pagevec *pvec = &get_cpu_var(lru_add_pvec);
+       struct pagevec *pvec = &get_locked_var(swapvec_lock, lru_add_pvec);
        int i;
 
        /*
@@ -348,7 +352,7 @@ static void __lru_cache_activate_page(struct page *page)
                }
        }
 
-       put_cpu_var(lru_add_pvec);
+       put_locked_var(swapvec_lock, lru_add_pvec);
 }
 
 /*
@@ -390,12 +394,12 @@ EXPORT_SYMBOL(mark_page_accessed);
 
 static void __lru_cache_add(struct page *page)
 {
-       struct pagevec *pvec = &get_cpu_var(lru_add_pvec);
+       struct pagevec *pvec = &get_locked_var(swapvec_lock, lru_add_pvec);
 
        get_page(page);
        if (!pagevec_add(pvec, page) || PageCompound(page))
                __pagevec_lru_add(pvec);
-       put_cpu_var(lru_add_pvec);
+       put_locked_var(swapvec_lock, lru_add_pvec);
 }
 
 /**
@@ -593,9 +597,15 @@ void lru_add_drain_cpu(int cpu)
                unsigned long flags;
 
                /* No harm done if a racing interrupt already did this */
-               local_irq_save(flags);
+#ifdef CONFIG_PREEMPT_RT_BASE
+               local_lock_irqsave_on(rotate_lock, flags, cpu);
                pagevec_move_tail(pvec);
-               local_irq_restore(flags);
+               local_unlock_irqrestore_on(rotate_lock, flags, cpu);
+#else
+               local_lock_irqsave(rotate_lock, flags);
+               pagevec_move_tail(pvec);
+               local_unlock_irqrestore(rotate_lock, flags);
+#endif
        }
 
        pvec = &per_cpu(lru_deactivate_file_pvecs, cpu);
@@ -627,11 +637,12 @@ void deactivate_file_page(struct page *page)
                return;
 
        if (likely(get_page_unless_zero(page))) {
-               struct pagevec *pvec = &get_cpu_var(lru_deactivate_file_pvecs);
+               struct pagevec *pvec = &get_locked_var(swapvec_lock,
+                                                      lru_deactivate_file_pvecs);
 
                if (!pagevec_add(pvec, page) || PageCompound(page))
                        pagevec_lru_move_fn(pvec, lru_deactivate_file_fn, NULL);
-               put_cpu_var(lru_deactivate_file_pvecs);
+               put_locked_var(swapvec_lock, lru_deactivate_file_pvecs);
        }
 }
 
@@ -646,27 +657,31 @@ void deactivate_file_page(struct page *page)
 void deactivate_page(struct page *page)
 {
        if (PageLRU(page) && PageActive(page) && !PageUnevictable(page)) {
-               struct pagevec *pvec = &get_cpu_var(lru_deactivate_pvecs);
+               struct pagevec *pvec = &get_locked_var(swapvec_lock,
+                                                      lru_deactivate_pvecs);
 
                get_page(page);
                if (!pagevec_add(pvec, page) || PageCompound(page))
                        pagevec_lru_move_fn(pvec, lru_deactivate_fn, NULL);
-               put_cpu_var(lru_deactivate_pvecs);
+               put_locked_var(swapvec_lock, lru_deactivate_pvecs);
        }
 }
 
 void lru_add_drain(void)
 {
-       lru_add_drain_cpu(get_cpu());
-       put_cpu();
+       lru_add_drain_cpu(local_lock_cpu(swapvec_lock));
+       local_unlock_cpu(swapvec_lock);
 }
 
-static void lru_add_drain_per_cpu(struct work_struct *dummy)
+#ifdef CONFIG_PREEMPT_RT_BASE
+static inline void remote_lru_add_drain(int cpu, struct cpumask *has_work)
 {
-       lru_add_drain();
+       local_lock_on(swapvec_lock, cpu);
+       lru_add_drain_cpu(cpu);
+       local_unlock_on(swapvec_lock, cpu);
 }
 
-static DEFINE_PER_CPU(struct work_struct, lru_add_drain_work);
+#else
 
 /*
  * lru_add_drain_wq is used to do lru_add_drain_all() from a WQ_MEM_RECLAIM
@@ -686,6 +701,22 @@ static int __init lru_init(void)
 }
 early_initcall(lru_init);
 
+static void lru_add_drain_per_cpu(struct work_struct *dummy)
+{
+       lru_add_drain();
+}
+
+static DEFINE_PER_CPU(struct work_struct, lru_add_drain_work);
+static inline void remote_lru_add_drain(int cpu, struct cpumask *has_work)
+{
+       struct work_struct *work = &per_cpu(lru_add_drain_work, cpu);
+
+       INIT_WORK(work, lru_add_drain_per_cpu);
+       queue_work_on(cpu, lru_add_drain_wq, work);
+       cpumask_set_cpu(cpu, has_work);
+}
+#endif
+
 void lru_add_drain_all(void)
 {
        static DEFINE_MUTEX(lock);
@@ -697,21 +728,18 @@ void lru_add_drain_all(void)
        cpumask_clear(&has_work);
 
        for_each_online_cpu(cpu) {
-               struct work_struct *work = &per_cpu(lru_add_drain_work, cpu);
-
                if (pagevec_count(&per_cpu(lru_add_pvec, cpu)) ||
                    pagevec_count(&per_cpu(lru_rotate_pvecs, cpu)) ||
                    pagevec_count(&per_cpu(lru_deactivate_file_pvecs, cpu)) ||
                    pagevec_count(&per_cpu(lru_deactivate_pvecs, cpu)) ||
-                   need_activate_page_drain(cpu)) {
-                       INIT_WORK(work, lru_add_drain_per_cpu);
-                       queue_work_on(cpu, lru_add_drain_wq, work);
-                       cpumask_set_cpu(cpu, &has_work);
-               }
+                   need_activate_page_drain(cpu))
+                       remote_lru_add_drain(cpu, &has_work);
        }
 
+#ifndef CONFIG_PREEMPT_RT_BASE
        for_each_cpu(cpu, &has_work)
                flush_work(&per_cpu(lru_add_drain_work, cpu));
+#endif
 
        put_online_cpus();
        mutex_unlock(&lock);
index befdc6f..813baac 100644 (file)
@@ -62,9 +62,12 @@ static void clear_exceptional_entry(struct address_space *mapping,
         * protected by mapping->tree_lock.
         */
        if (!workingset_node_shadows(node) &&
-           !list_empty(&node->private_list))
-               list_lru_del(&workingset_shadow_nodes,
+           !list_empty(&node->private_list)) {
+               local_lock(workingset_shadow_lock);
+               list_lru_del(&__workingset_shadow_nodes,
                                &node->private_list);
+               local_unlock(workingset_shadow_lock);
+       }
        __radix_tree_delete_node(&mapping->page_tree, node);
 unlock:
        spin_unlock_irq(&mapping->tree_lock);
index 4d60424..ab58f20 100644 (file)
@@ -882,7 +882,7 @@ static void *new_vmap_block(unsigned int order, gfp_t gfp_mask)
        struct vmap_block *vb;
        struct vmap_area *va;
        unsigned long vb_idx;
-       int node, err;
+       int node, err, cpu;
        void *vaddr;
 
        node = numa_node_id();
@@ -925,11 +925,12 @@ static void *new_vmap_block(unsigned int order, gfp_t gfp_mask)
        BUG_ON(err);
        radix_tree_preload_end();
 
-       vbq = &get_cpu_var(vmap_block_queue);
+       cpu = get_cpu_light();
+       vbq = this_cpu_ptr(&vmap_block_queue);
        spin_lock(&vbq->lock);
        list_add_tail_rcu(&vb->free_list, &vbq->free);
        spin_unlock(&vbq->lock);
-       put_cpu_var(vmap_block_queue);
+       put_cpu_light();
 
        return vaddr;
 }
@@ -998,6 +999,7 @@ static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
        struct vmap_block *vb;
        void *vaddr = NULL;
        unsigned int order;
+       int cpu;
 
        BUG_ON(offset_in_page(size));
        BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC);
@@ -1012,7 +1014,8 @@ static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
        order = get_order(size);
 
        rcu_read_lock();
-       vbq = &get_cpu_var(vmap_block_queue);
+       cpu = get_cpu_light();
+       vbq = this_cpu_ptr(&vmap_block_queue);
        list_for_each_entry_rcu(vb, &vbq->free, free_list) {
                unsigned long pages_off;
 
@@ -1035,7 +1038,7 @@ static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
                break;
        }
 
-       put_cpu_var(vmap_block_queue);
+       put_cpu_light();
        rcu_read_unlock();
 
        /* Allocate new block if nothing was found */
index e60435d..ea66004 100644 (file)
@@ -245,6 +245,7 @@ void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
        long x;
        long t;
 
+       preempt_disable_rt();
        x = delta + __this_cpu_read(*p);
 
        t = __this_cpu_read(pcp->stat_threshold);
@@ -254,6 +255,7 @@ void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
                x = 0;
        }
        __this_cpu_write(*p, x);
+       preempt_enable_rt();
 }
 EXPORT_SYMBOL(__mod_zone_page_state);
 
@@ -265,6 +267,7 @@ void __mod_node_page_state(struct pglist_data *pgdat, enum node_stat_item item,
        long x;
        long t;
 
+       preempt_disable_rt();
        x = delta + __this_cpu_read(*p);
 
        t = __this_cpu_read(pcp->stat_threshold);
@@ -274,6 +277,7 @@ void __mod_node_page_state(struct pglist_data *pgdat, enum node_stat_item item,
                x = 0;
        }
        __this_cpu_write(*p, x);
+       preempt_enable_rt();
 }
 EXPORT_SYMBOL(__mod_node_page_state);
 
@@ -306,6 +310,7 @@ void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
        s8 __percpu *p = pcp->vm_stat_diff + item;
        s8 v, t;
 
+       preempt_disable_rt();
        v = __this_cpu_inc_return(*p);
        t = __this_cpu_read(pcp->stat_threshold);
        if (unlikely(v > t)) {
@@ -314,6 +319,7 @@ void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
                zone_page_state_add(v + overstep, zone, item);
                __this_cpu_write(*p, -overstep);
        }
+       preempt_enable_rt();
 }
 
 void __inc_node_state(struct pglist_data *pgdat, enum node_stat_item item)
@@ -322,6 +328,7 @@ void __inc_node_state(struct pglist_data *pgdat, enum node_stat_item item)
        s8 __percpu *p = pcp->vm_node_stat_diff + item;
        s8 v, t;
 
+       preempt_disable_rt();
        v = __this_cpu_inc_return(*p);
        t = __this_cpu_read(pcp->stat_threshold);
        if (unlikely(v > t)) {
@@ -330,6 +337,7 @@ void __inc_node_state(struct pglist_data *pgdat, enum node_stat_item item)
                node_page_state_add(v + overstep, pgdat, item);
                __this_cpu_write(*p, -overstep);
        }
+       preempt_enable_rt();
 }
 
 void __inc_zone_page_state(struct page *page, enum zone_stat_item item)
@@ -350,6 +358,7 @@ void __dec_zone_state(struct zone *zone, enum zone_stat_item item)
        s8 __percpu *p = pcp->vm_stat_diff + item;
        s8 v, t;
 
+       preempt_disable_rt();
        v = __this_cpu_dec_return(*p);
        t = __this_cpu_read(pcp->stat_threshold);
        if (unlikely(v < - t)) {
@@ -358,6 +367,7 @@ void __dec_zone_state(struct zone *zone, enum zone_stat_item item)
                zone_page_state_add(v - overstep, zone, item);
                __this_cpu_write(*p, overstep);
        }
+       preempt_enable_rt();
 }
 
 void __dec_node_state(struct pglist_data *pgdat, enum node_stat_item item)
@@ -366,6 +376,7 @@ void __dec_node_state(struct pglist_data *pgdat, enum node_stat_item item)
        s8 __percpu *p = pcp->vm_node_stat_diff + item;
        s8 v, t;
 
+       preempt_disable_rt();
        v = __this_cpu_dec_return(*p);
        t = __this_cpu_read(pcp->stat_threshold);
        if (unlikely(v < - t)) {
@@ -374,6 +385,7 @@ void __dec_node_state(struct pglist_data *pgdat, enum node_stat_item item)
                node_page_state_add(v - overstep, pgdat, item);
                __this_cpu_write(*p, overstep);
        }
+       preempt_enable_rt();
 }
 
 void __dec_zone_page_state(struct page *page, enum zone_stat_item item)
index 4c4f056..b97b1e8 100644 (file)
@@ -334,7 +334,8 @@ out:
  * point where they would still be useful.
  */
 
-struct list_lru workingset_shadow_nodes;
+struct list_lru __workingset_shadow_nodes;
+DEFINE_LOCAL_IRQ_LOCK(workingset_shadow_lock);
 
 static unsigned long count_shadow_nodes(struct shrinker *shrinker,
                                        struct shrink_control *sc)
@@ -344,9 +345,9 @@ static unsigned long count_shadow_nodes(struct shrinker *shrinker,
        unsigned long pages;
 
        /* list_lru lock nests inside IRQ-safe mapping->tree_lock */
-       local_irq_disable();
-       shadow_nodes = list_lru_shrink_count(&workingset_shadow_nodes, sc);
-       local_irq_enable();
+       local_lock_irq(workingset_shadow_lock);
+       shadow_nodes = list_lru_shrink_count(&__workingset_shadow_nodes, sc);
+       local_unlock_irq(workingset_shadow_lock);
 
        if (sc->memcg) {
                pages = mem_cgroup_node_nr_lru_pages(sc->memcg, sc->nid,
@@ -438,9 +439,9 @@ static enum lru_status shadow_lru_isolate(struct list_head *item,
        spin_unlock(&mapping->tree_lock);
        ret = LRU_REMOVED_RETRY;
 out:
-       local_irq_enable();
+       local_unlock_irq(workingset_shadow_lock);
        cond_resched();
-       local_irq_disable();
+       local_lock_irq(workingset_shadow_lock);
        spin_lock(lru_lock);
        return ret;
 }
@@ -451,10 +452,10 @@ static unsigned long scan_shadow_nodes(struct shrinker *shrinker,
        unsigned long ret;
 
        /* list_lru lock nests inside IRQ-safe mapping->tree_lock */
-       local_irq_disable();
-       ret =  list_lru_shrink_walk(&workingset_shadow_nodes, sc,
+       local_lock_irq(workingset_shadow_lock);
+       ret =  list_lru_shrink_walk(&__workingset_shadow_nodes, sc,
                                    shadow_lru_isolate, NULL);
-       local_irq_enable();
+       local_unlock_irq(workingset_shadow_lock);
        return ret;
 }
 
@@ -492,7 +493,7 @@ static int __init workingset_init(void)
        pr_info("workingset: timestamp_bits=%d max_order=%d bucket_order=%u\n",
               timestamp_bits, max_order, bucket_order);
 
-       ret = __list_lru_init(&workingset_shadow_nodes, true, &shadow_nodes_key);
+       ret = __list_lru_init(&__workingset_shadow_nodes, true, &shadow_nodes_key);
        if (ret)
                goto err;
        ret = register_shrinker(&workingset_shadow_shrinker);
@@ -500,7 +501,7 @@ static int __init workingset_init(void)
                goto err_list_lru;
        return 0;
 err_list_lru:
-       list_lru_destroy(&workingset_shadow_nodes);
+       list_lru_destroy(&__workingset_shadow_nodes);
 err:
        return ret;
 }
index e4cca3f..5b5b631 100644 (file)
@@ -54,6 +54,7 @@
 #include <linux/migrate.h>
 #include <linux/wait.h>
 #include <linux/pagemap.h>
+#include <linux/locallock.h>
 
 #define ZSPAGE_MAGIC   0x58
 
  */
 #define ZS_MAX_ZSPAGE_ORDER 2
 #define ZS_MAX_PAGES_PER_ZSPAGE (_AC(1, UL) << ZS_MAX_ZSPAGE_ORDER)
-
 #define ZS_HANDLE_SIZE (sizeof(unsigned long))
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+
+struct zsmalloc_handle {
+       unsigned long addr;
+       struct mutex lock;
+};
+
+#define ZS_HANDLE_ALLOC_SIZE (sizeof(struct zsmalloc_handle))
+
+#else
+
+#define ZS_HANDLE_ALLOC_SIZE (sizeof(unsigned long))
+#endif
+
 /*
  * Object location (<PFN>, <obj_idx>) is encoded as
  * as single (unsigned long) handle value.
@@ -332,7 +346,7 @@ static void SetZsPageMovable(struct zs_pool *pool, struct zspage *zspage) {}
 
 static int create_cache(struct zs_pool *pool)
 {
-       pool->handle_cachep = kmem_cache_create("zs_handle", ZS_HANDLE_SIZE,
+       pool->handle_cachep = kmem_cache_create("zs_handle", ZS_HANDLE_ALLOC_SIZE,
                                        0, 0, NULL);
        if (!pool->handle_cachep)
                return 1;
@@ -356,10 +370,27 @@ static void destroy_cache(struct zs_pool *pool)
 
 static unsigned long cache_alloc_handle(struct zs_pool *pool, gfp_t gfp)
 {
-       return (unsigned long)kmem_cache_alloc(pool->handle_cachep,
-                       gfp & ~(__GFP_HIGHMEM|__GFP_MOVABLE));
+       void *p;
+
+       p = kmem_cache_alloc(pool->handle_cachep,
+                            gfp & ~(__GFP_HIGHMEM|__GFP_MOVABLE));
+#ifdef CONFIG_PREEMPT_RT_FULL
+       if (p) {
+               struct zsmalloc_handle *zh = p;
+
+               mutex_init(&zh->lock);
+       }
+#endif
+       return (unsigned long)p;
 }
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+static struct zsmalloc_handle *zs_get_pure_handle(unsigned long handle)
+{
+       return (void *)(handle &~((1 << OBJ_TAG_BITS) - 1));
+}
+#endif
+
 static void cache_free_handle(struct zs_pool *pool, unsigned long handle)
 {
        kmem_cache_free(pool->handle_cachep, (void *)handle);
@@ -378,12 +409,18 @@ static void cache_free_zspage(struct zs_pool *pool, struct zspage *zspage)
 
 static void record_obj(unsigned long handle, unsigned long obj)
 {
+#ifdef CONFIG_PREEMPT_RT_FULL
+       struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+       WRITE_ONCE(zh->addr, obj);
+#else
        /*
         * lsb of @obj represents handle lock while other bits
         * represent object value the handle is pointing so
         * updating shouldn't do store tearing.
         */
        WRITE_ONCE(*(unsigned long *)handle, obj);
+#endif
 }
 
 /* zpool driver */
@@ -472,6 +509,7 @@ MODULE_ALIAS("zpool-zsmalloc");
 
 /* per-cpu VM mapping areas for zspage accesses that cross page boundaries */
 static DEFINE_PER_CPU(struct mapping_area, zs_map_area);
+static DEFINE_LOCAL_IRQ_LOCK(zs_map_area_lock);
 
 static bool is_zspage_isolated(struct zspage *zspage)
 {
@@ -910,7 +948,13 @@ static unsigned long location_to_obj(struct page *page, unsigned int obj_idx)
 
 static unsigned long handle_to_obj(unsigned long handle)
 {
+#ifdef CONFIG_PREEMPT_RT_FULL
+       struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+       return zh->addr;
+#else
        return *(unsigned long *)handle;
+#endif
 }
 
 static unsigned long obj_to_head(struct page *page, void *obj)
@@ -924,22 +968,46 @@ static unsigned long obj_to_head(struct page *page, void *obj)
 
 static inline int testpin_tag(unsigned long handle)
 {
+#ifdef CONFIG_PREEMPT_RT_FULL
+       struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+       return mutex_is_locked(&zh->lock);
+#else
        return bit_spin_is_locked(HANDLE_PIN_BIT, (unsigned long *)handle);
+#endif
 }
 
 static inline int trypin_tag(unsigned long handle)
 {
+#ifdef CONFIG_PREEMPT_RT_FULL
+       struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+       return mutex_trylock(&zh->lock);
+#else
        return bit_spin_trylock(HANDLE_PIN_BIT, (unsigned long *)handle);
+#endif
 }
 
 static void pin_tag(unsigned long handle)
 {
+#ifdef CONFIG_PREEMPT_RT_FULL
+       struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+       return mutex_lock(&zh->lock);
+#else
        bit_spin_lock(HANDLE_PIN_BIT, (unsigned long *)handle);
+#endif
 }
 
 static void unpin_tag(unsigned long handle)
 {
+#ifdef CONFIG_PREEMPT_RT_FULL
+       struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+       return mutex_unlock(&zh->lock);
+#else
        bit_spin_unlock(HANDLE_PIN_BIT, (unsigned long *)handle);
+#endif
 }
 
 static void reset_page(struct page *page)
@@ -1431,7 +1499,7 @@ void *zs_map_object(struct zs_pool *pool, unsigned long handle,
        class = pool->size_class[class_idx];
        off = (class->size * obj_idx) & ~PAGE_MASK;
 
-       area = &get_cpu_var(zs_map_area);
+       area = &get_locked_var(zs_map_area_lock, zs_map_area);
        area->vm_mm = mm;
        if (off + class->size <= PAGE_SIZE) {
                /* this object is contained entirely within a page */
@@ -1485,7 +1553,7 @@ void zs_unmap_object(struct zs_pool *pool, unsigned long handle)
 
                __zs_unmap_object(area, pages, off, class->size);
        }
-       put_cpu_var(zs_map_area);
+       put_locked_var(zs_map_area_lock, zs_map_area);
 
        migrate_read_unlock(zspage);
        unpin_tag(handle);
index 6b93384..766eb83 100644 (file)
@@ -254,15 +254,13 @@ void hci_send_to_sock(struct hci_dev *hdev, struct sk_buff *skb)
 }
 
 /* Send frame to sockets with specific channel */
-void hci_send_to_channel(unsigned short channel, struct sk_buff *skb,
-                        int flag, struct sock *skip_sk)
+static void __hci_send_to_channel(unsigned short channel, struct sk_buff *skb,
+                                 int flag, struct sock *skip_sk)
 {
        struct sock *sk;
 
        BT_DBG("channel %u len %d", channel, skb->len);
 
-       read_lock(&hci_sk_list.lock);
-
        sk_for_each(sk, &hci_sk_list.head) {
                struct sk_buff *nskb;
 
@@ -288,6 +286,13 @@ void hci_send_to_channel(unsigned short channel, struct sk_buff *skb,
                        kfree_skb(nskb);
        }
 
+}
+
+void hci_send_to_channel(unsigned short channel, struct sk_buff *skb,
+                        int flag, struct sock *skip_sk)
+{
+       read_lock(&hci_sk_list.lock);
+       __hci_send_to_channel(channel, skb, flag, skip_sk);
        read_unlock(&hci_sk_list.lock);
 }
 
@@ -391,8 +396,8 @@ void hci_send_monitor_ctrl_event(struct hci_dev *hdev, u16 event,
                hdr->index = index;
                hdr->len = cpu_to_le16(skb->len - HCI_MON_HDR_SIZE);
 
-               hci_send_to_channel(HCI_CHANNEL_MONITOR, skb,
-                                   HCI_SOCK_TRUSTED, NULL);
+               __hci_send_to_channel(HCI_CHANNEL_MONITOR, skb,
+                                     HCI_SOCK_TRUSTED, NULL);
                kfree_skb(skb);
        }
 
index 9ac591d..51da1ba 100644 (file)
@@ -212,14 +212,14 @@ static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex)
 static inline void rps_lock(struct softnet_data *sd)
 {
 #ifdef CONFIG_RPS
-       spin_lock(&sd->input_pkt_queue.lock);
+       raw_spin_lock(&sd->input_pkt_queue.raw_lock);
 #endif
 }
 
 static inline void rps_unlock(struct softnet_data *sd)
 {
 #ifdef CONFIG_RPS
-       spin_unlock(&sd->input_pkt_queue.lock);
+       raw_spin_unlock(&sd->input_pkt_queue.raw_lock);
 #endif
 }
 
@@ -2312,6 +2312,7 @@ static void __netif_reschedule(struct Qdisc *q)
        sd->output_queue_tailp = &q->next_sched;
        raise_softirq_irqoff(NET_TX_SOFTIRQ);
        local_irq_restore(flags);
+       preempt_check_resched_rt();
 }
 
 void __netif_schedule(struct Qdisc *q)
@@ -2396,6 +2397,7 @@ void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
        __this_cpu_write(softnet_data.completion_queue, skb);
        raise_softirq_irqoff(NET_TX_SOFTIRQ);
        local_irq_restore(flags);
+       preempt_check_resched_rt();
 }
 EXPORT_SYMBOL(__dev_kfree_skb_irq);
 
@@ -3148,7 +3150,11 @@ static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
         * This permits qdisc->running owner to get the lock more
         * often and dequeue packets faster.
         */
+#ifdef CONFIG_PREEMPT_RT_FULL
+       contended = true;
+#else
        contended = qdisc_is_running(q);
+#endif
        if (unlikely(contended))
                spin_lock(&q->busylock);
 
@@ -3219,8 +3225,10 @@ static void skb_update_prio(struct sk_buff *skb)
 #define skb_update_prio(skb)
 #endif
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 DEFINE_PER_CPU(int, xmit_recursion);
 EXPORT_SYMBOL(xmit_recursion);
+#endif
 
 /**
  *     dev_loopback_xmit - loop back @skb
@@ -3453,9 +3461,12 @@ static int __dev_queue_xmit(struct sk_buff *skb, void *accel_priv)
        if (dev->flags & IFF_UP) {
                int cpu = smp_processor_id(); /* ok because BHs are off */
 
+#ifdef CONFIG_PREEMPT_RT_FULL
+               if (txq->xmit_lock_owner != current) {
+#else
                if (txq->xmit_lock_owner != cpu) {
-                       if (unlikely(__this_cpu_read(xmit_recursion) >
-                                    XMIT_RECURSION_LIMIT))
+#endif
+                       if (unlikely(xmit_rec_read() > XMIT_RECURSION_LIMIT))
                                goto recursion_alert;
 
                        skb = validate_xmit_skb(skb, dev);
@@ -3465,9 +3476,9 @@ static int __dev_queue_xmit(struct sk_buff *skb, void *accel_priv)
                        HARD_TX_LOCK(dev, txq, cpu);
 
                        if (!netif_xmit_stopped(txq)) {
-                               __this_cpu_inc(xmit_recursion);
+                               xmit_rec_inc();
                                skb = dev_hard_start_xmit(skb, dev, txq, &rc);
-                               __this_cpu_dec(xmit_recursion);
+                               xmit_rec_dec();
                                if (dev_xmit_complete(rc)) {
                                        HARD_TX_UNLOCK(dev, txq);
                                        goto out;
@@ -3841,6 +3852,7 @@ drop:
        rps_unlock(sd);
 
        local_irq_restore(flags);
+       preempt_check_resched_rt();
 
        atomic_long_inc(&skb->dev->rx_dropped);
        kfree_skb(skb);
@@ -3859,7 +3871,7 @@ static int netif_rx_internal(struct sk_buff *skb)
                struct rps_dev_flow voidflow, *rflow = &voidflow;
                int cpu;
 
-               preempt_disable();
+               migrate_disable();
                rcu_read_lock();
 
                cpu = get_rps_cpu(skb->dev, skb, &rflow);
@@ -3869,13 +3881,13 @@ static int netif_rx_internal(struct sk_buff *skb)
                ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
 
                rcu_read_unlock();
-               preempt_enable();
+               migrate_enable();
        } else
 #endif
        {
                unsigned int qtail;
-               ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
-               put_cpu();
+               ret = enqueue_to_backlog(skb, get_cpu_light(), &qtail);
+               put_cpu_light();
        }
        return ret;
 }
@@ -3909,11 +3921,9 @@ int netif_rx_ni(struct sk_buff *skb)
 
        trace_netif_rx_ni_entry(skb);
 
-       preempt_disable();
+       local_bh_disable();
        err = netif_rx_internal(skb);
-       if (local_softirq_pending())
-               do_softirq();
-       preempt_enable();
+       local_bh_enable();
 
        return err;
 }
@@ -4402,11 +4412,14 @@ static void flush_backlog(struct work_struct *work)
        skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
                if (skb->dev->reg_state == NETREG_UNREGISTERING) {
                        __skb_unlink(skb, &sd->process_queue);
-                       kfree_skb(skb);
+                       __skb_queue_tail(&sd->tofree_queue, skb);
                        input_queue_head_incr(sd);
                }
        }
+       if (!skb_queue_empty(&sd->tofree_queue))
+               raise_softirq_irqoff(NET_RX_SOFTIRQ);
        local_bh_enable();
+
 }
 
 static void flush_all_backlogs(void)
@@ -4901,6 +4914,7 @@ static void net_rps_action_and_irq_enable(struct softnet_data *sd)
                sd->rps_ipi_list = NULL;
 
                local_irq_enable();
+               preempt_check_resched_rt();
 
                /* Send pending IPI's to kick RPS processing on remote cpus. */
                while (remsd) {
@@ -4914,6 +4928,7 @@ static void net_rps_action_and_irq_enable(struct softnet_data *sd)
        } else
 #endif
                local_irq_enable();
+       preempt_check_resched_rt();
 }
 
 static bool sd_has_rps_ipi_waiting(struct softnet_data *sd)
@@ -4943,7 +4958,9 @@ static int process_backlog(struct napi_struct *napi, int quota)
        while (again) {
                struct sk_buff *skb;
 
+               local_irq_disable();
                while ((skb = __skb_dequeue(&sd->process_queue))) {
+                       local_irq_enable();
                        rcu_read_lock();
                        __netif_receive_skb(skb);
                        rcu_read_unlock();
@@ -4951,9 +4968,9 @@ static int process_backlog(struct napi_struct *napi, int quota)
                        if (++work >= quota)
                                return work;
 
+                       local_irq_disable();
                }
 
-               local_irq_disable();
                rps_lock(sd);
                if (skb_queue_empty(&sd->input_pkt_queue)) {
                        /*
@@ -4991,9 +5008,11 @@ void __napi_schedule(struct napi_struct *n)
        local_irq_save(flags);
        ____napi_schedule(this_cpu_ptr(&softnet_data), n);
        local_irq_restore(flags);
+       preempt_check_resched_rt();
 }
 EXPORT_SYMBOL(__napi_schedule);
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 /**
  * __napi_schedule_irqoff - schedule for receive
  * @n: entry to schedule
@@ -5005,6 +5024,7 @@ void __napi_schedule_irqoff(struct napi_struct *n)
        ____napi_schedule(this_cpu_ptr(&softnet_data), n);
 }
 EXPORT_SYMBOL(__napi_schedule_irqoff);
+#endif
 
 void __napi_complete(struct napi_struct *n)
 {
@@ -5298,13 +5318,21 @@ static __latent_entropy void net_rx_action(struct softirq_action *h)
        struct softnet_data *sd = this_cpu_ptr(&softnet_data);
        unsigned long time_limit = jiffies + 2;
        int budget = netdev_budget;
+       struct sk_buff_head tofree_q;
+       struct sk_buff *skb;
        LIST_HEAD(list);
        LIST_HEAD(repoll);
 
+       __skb_queue_head_init(&tofree_q);
+
        local_irq_disable();
+       skb_queue_splice_init(&sd->tofree_queue, &tofree_q);
        list_splice_init(&sd->poll_list, &list);
        local_irq_enable();
 
+       while ((skb = __skb_dequeue(&tofree_q)))
+               kfree_skb(skb);
+
        for (;;) {
                struct napi_struct *n;
 
@@ -5335,7 +5363,7 @@ static __latent_entropy void net_rx_action(struct softirq_action *h)
        list_splice_tail(&repoll, &list);
        list_splice(&list, &sd->poll_list);
        if (!list_empty(&sd->poll_list))
-               __raise_softirq_irqoff(NET_RX_SOFTIRQ);
+               __raise_softirq_irqoff_ksoft(NET_RX_SOFTIRQ);
 
        net_rps_action_and_irq_enable(sd);
 }
@@ -7169,7 +7197,7 @@ static void netdev_init_one_queue(struct net_device *dev,
        /* Initialize queue lock */
        spin_lock_init(&queue->_xmit_lock);
        netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type);
-       queue->xmit_lock_owner = -1;
+       netdev_queue_clear_owner(queue);
        netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
        queue->dev = dev;
 #ifdef CONFIG_BQL
@@ -8111,16 +8139,20 @@ static int dev_cpu_callback(struct notifier_block *nfb,
 
        raise_softirq_irqoff(NET_TX_SOFTIRQ);
        local_irq_enable();
+       preempt_check_resched_rt();
 
        /* Process offline CPU's input_pkt_queue */
        while ((skb = __skb_dequeue(&oldsd->process_queue))) {
                netif_rx_ni(skb);
                input_queue_head_incr(oldsd);
        }
-       while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) {
+       while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) {
                netif_rx_ni(skb);
                input_queue_head_incr(oldsd);
        }
+       while ((skb = __skb_dequeue(&oldsd->tofree_queue))) {
+               kfree_skb(skb);
+       }
 
        return NOTIFY_OK;
 }
@@ -8427,8 +8459,9 @@ static int __init net_dev_init(void)
 
                INIT_WORK(flush, flush_backlog);
 
-               skb_queue_head_init(&sd->input_pkt_queue);
-               skb_queue_head_init(&sd->process_queue);
+               skb_queue_head_init_raw(&sd->input_pkt_queue);
+               skb_queue_head_init_raw(&sd->process_queue);
+               skb_queue_head_init_raw(&sd->tofree_queue);
                INIT_LIST_HEAD(&sd->poll_list);
                sd->output_queue_tailp = &sd->output_queue;
 #ifdef CONFIG_RPS
index c385c55..feb96c2 100644 (file)
@@ -1657,7 +1657,7 @@ static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb)
 {
        int ret;
 
-       if (unlikely(__this_cpu_read(xmit_recursion) > XMIT_RECURSION_LIMIT)) {
+       if (unlikely(xmit_rec_read() > XMIT_RECURSION_LIMIT)) {
                net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
                kfree_skb(skb);
                return -ENETDOWN;
@@ -1665,9 +1665,9 @@ static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb)
 
        skb->dev = dev;
 
-       __this_cpu_inc(xmit_recursion);
+       xmit_rec_inc();
        ret = dev_queue_xmit(skb);
-       __this_cpu_dec(xmit_recursion);
+       xmit_rec_dec();
 
        return ret;
 }
index cad8e79..2a9364f 100644 (file)
@@ -84,7 +84,7 @@ struct gen_estimator
        struct gnet_stats_basic_packed  *bstats;
        struct gnet_stats_rate_est64    *rate_est;
        spinlock_t              *stats_lock;
-       seqcount_t              *running;
+       net_seqlock_t           *running;
        int                     ewma_log;
        u32                     last_packets;
        unsigned long           avpps;
@@ -213,7 +213,7 @@ int gen_new_estimator(struct gnet_stats_basic_packed *bstats,
                      struct gnet_stats_basic_cpu __percpu *cpu_bstats,
                      struct gnet_stats_rate_est64 *rate_est,
                      spinlock_t *stats_lock,
-                     seqcount_t *running,
+                     net_seqlock_t *running,
                      struct nlattr *opt)
 {
        struct gen_estimator *est;
@@ -309,7 +309,7 @@ int gen_replace_estimator(struct gnet_stats_basic_packed *bstats,
                          struct gnet_stats_basic_cpu __percpu *cpu_bstats,
                          struct gnet_stats_rate_est64 *rate_est,
                          spinlock_t *stats_lock,
-                         seqcount_t *running, struct nlattr *opt)
+                         net_seqlock_t *running, struct nlattr *opt)
 {
        gen_kill_estimator(bstats, rate_est);
        return gen_new_estimator(bstats, cpu_bstats, rate_est, stats_lock, running, opt);
index 18f17e1..9afe5d6 100644 (file)
@@ -142,7 +142,7 @@ __gnet_stats_copy_basic_cpu(struct gnet_stats_basic_packed *bstats,
 }
 
 void
-__gnet_stats_copy_basic(const seqcount_t *running,
+__gnet_stats_copy_basic(net_seqlock_t *running,
                        struct gnet_stats_basic_packed *bstats,
                        struct gnet_stats_basic_cpu __percpu *cpu,
                        struct gnet_stats_basic_packed *b)
@@ -155,10 +155,10 @@ __gnet_stats_copy_basic(const seqcount_t *running,
        }
        do {
                if (running)
-                       seq = read_seqcount_begin(running);
+                       seq = net_seq_begin(running);
                bstats->bytes = b->bytes;
                bstats->packets = b->packets;
-       } while (running && read_seqcount_retry(running, seq));
+       } while (running && net_seq_retry(running, seq));
 }
 EXPORT_SYMBOL(__gnet_stats_copy_basic);
 
@@ -176,7 +176,7 @@ EXPORT_SYMBOL(__gnet_stats_copy_basic);
  * if the room in the socket buffer was not sufficient.
  */
 int
-gnet_stats_copy_basic(const seqcount_t *running,
+gnet_stats_copy_basic(net_seqlock_t *running,
                      struct gnet_dump *d,
                      struct gnet_stats_basic_cpu __percpu *cpu,
                      struct gnet_stats_basic_packed *b)
index a4c4234..3a4bf11 100644 (file)
@@ -64,6 +64,7 @@
 #include <linux/errqueue.h>
 #include <linux/prefetch.h>
 #include <linux/if_vlan.h>
+#include <linux/locallock.h>
 
 #include <net/protocol.h>
 #include <net/dst.h>
@@ -360,6 +361,8 @@ struct napi_alloc_cache {
 
 static DEFINE_PER_CPU(struct page_frag_cache, netdev_alloc_cache);
 static DEFINE_PER_CPU(struct napi_alloc_cache, napi_alloc_cache);
+static DEFINE_LOCAL_IRQ_LOCK(netdev_alloc_lock);
+static DEFINE_LOCAL_IRQ_LOCK(napi_alloc_cache_lock);
 
 static void *__netdev_alloc_frag(unsigned int fragsz, gfp_t gfp_mask)
 {
@@ -367,10 +370,10 @@ static void *__netdev_alloc_frag(unsigned int fragsz, gfp_t gfp_mask)
        unsigned long flags;
        void *data;
 
-       local_irq_save(flags);
+       local_lock_irqsave(netdev_alloc_lock, flags);
        nc = this_cpu_ptr(&netdev_alloc_cache);
        data = __alloc_page_frag(nc, fragsz, gfp_mask);
-       local_irq_restore(flags);
+       local_unlock_irqrestore(netdev_alloc_lock, flags);
        return data;
 }
 
@@ -391,9 +394,13 @@ EXPORT_SYMBOL(netdev_alloc_frag);
 
 static void *__napi_alloc_frag(unsigned int fragsz, gfp_t gfp_mask)
 {
-       struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);
+       struct napi_alloc_cache *nc;
+       void *data;
 
-       return __alloc_page_frag(&nc->page, fragsz, gfp_mask);
+       nc = &get_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
+       data = __alloc_page_frag(&nc->page, fragsz, gfp_mask);
+       put_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
+       return data;
 }
 
 void *napi_alloc_frag(unsigned int fragsz)
@@ -442,13 +449,13 @@ struct sk_buff *__netdev_alloc_skb(struct net_device *dev, unsigned int len,
        if (sk_memalloc_socks())
                gfp_mask |= __GFP_MEMALLOC;
 
-       local_irq_save(flags);
+       local_lock_irqsave(netdev_alloc_lock, flags);
 
        nc = this_cpu_ptr(&netdev_alloc_cache);
        data = __alloc_page_frag(nc, len, gfp_mask);
        pfmemalloc = nc->pfmemalloc;
 
-       local_irq_restore(flags);
+       local_unlock_irqrestore(netdev_alloc_lock, flags);
 
        if (unlikely(!data))
                return NULL;
@@ -489,9 +496,10 @@ EXPORT_SYMBOL(__netdev_alloc_skb);
 struct sk_buff *__napi_alloc_skb(struct napi_struct *napi, unsigned int len,
                                 gfp_t gfp_mask)
 {
-       struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);
+       struct napi_alloc_cache *nc;
        struct sk_buff *skb;
        void *data;
+       bool pfmemalloc;
 
        len += NET_SKB_PAD + NET_IP_ALIGN;
 
@@ -509,7 +517,10 @@ struct sk_buff *__napi_alloc_skb(struct napi_struct *napi, unsigned int len,
        if (sk_memalloc_socks())
                gfp_mask |= __GFP_MEMALLOC;
 
+       nc = &get_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
        data = __alloc_page_frag(&nc->page, len, gfp_mask);
+       pfmemalloc = nc->page.pfmemalloc;
+       put_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
        if (unlikely(!data))
                return NULL;
 
@@ -520,7 +531,7 @@ struct sk_buff *__napi_alloc_skb(struct napi_struct *napi, unsigned int len,
        }
 
        /* use OR instead of assignment to avoid clearing of bits in mask */
-       if (nc->page.pfmemalloc)
+       if (pfmemalloc)
                skb->pfmemalloc = 1;
        skb->head_frag = 1;
 
@@ -764,23 +775,26 @@ EXPORT_SYMBOL(consume_skb);
 
 void __kfree_skb_flush(void)
 {
-       struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);
+       struct napi_alloc_cache *nc;
 
+       nc = &get_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
        /* flush skb_cache if containing objects */
        if (nc->skb_count) {
                kmem_cache_free_bulk(skbuff_head_cache, nc->skb_count,
                                     nc->skb_cache);
                nc->skb_count = 0;
        }
+       put_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
 }
 
 static inline void _kfree_skb_defer(struct sk_buff *skb)
 {
-       struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);
+       struct napi_alloc_cache *nc;
 
        /* drop skb->head and call any destructors for packet */
        skb_release_all(skb);
 
+       nc = &get_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
        /* record skb to CPU local list */
        nc->skb_cache[nc->skb_count++] = skb;
 
@@ -795,6 +809,7 @@ static inline void _kfree_skb_defer(struct sk_buff *skb)
                                     nc->skb_cache);
                nc->skb_count = 0;
        }
+       put_locked_var(napi_alloc_cache_lock, napi_alloc_cache);
 }
 void __kfree_skb_defer(struct sk_buff *skb)
 {
index 123f3d7..ddd1c69 100644 (file)
@@ -2536,12 +2536,11 @@ void lock_sock_nested(struct sock *sk, int subclass)
        if (sk->sk_lock.owned)
                __lock_sock(sk);
        sk->sk_lock.owned = 1;
-       spin_unlock(&sk->sk_lock.slock);
+       spin_unlock_bh(&sk->sk_lock.slock);
        /*
         * The sk_lock has mutex_lock() semantics here:
         */
        mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
-       local_bh_enable();
 }
 EXPORT_SYMBOL(lock_sock_nested);
 
index 6b66f05..59675d1 100644 (file)
@@ -69,6 +69,7 @@
 #include <linux/jiffies.h>
 #include <linux/kernel.h>
 #include <linux/fcntl.h>
+#include <linux/sysrq.h>
 #include <linux/socket.h>
 #include <linux/in.h>
 #include <linux/inet.h>
@@ -77,6 +78,7 @@
 #include <linux/string.h>
 #include <linux/netfilter_ipv4.h>
 #include <linux/slab.h>
+#include <linux/locallock.h>
 #include <net/snmp.h>
 #include <net/ip.h>
 #include <net/route.h>
@@ -204,6 +206,8 @@ static const struct icmp_control icmp_pointers[NR_ICMP_TYPES+1];
  *
  *     On SMP we have one ICMP socket per-cpu.
  */
+static DEFINE_LOCAL_IRQ_LOCK(icmp_sk_lock);
+
 static struct sock *icmp_sk(struct net *net)
 {
        return *this_cpu_ptr(net->ipv4.icmp_sk);
@@ -215,12 +219,18 @@ static inline struct sock *icmp_xmit_lock(struct net *net)
 
        local_bh_disable();
 
+       if (!local_trylock(icmp_sk_lock)) {
+               local_bh_enable();
+               return NULL;
+       }
+
        sk = icmp_sk(net);
 
        if (unlikely(!spin_trylock(&sk->sk_lock.slock))) {
                /* This can happen if the output path signals a
                 * dst_link_failure() for an outgoing ICMP packet.
                 */
+               local_unlock(icmp_sk_lock);
                local_bh_enable();
                return NULL;
        }
@@ -230,6 +240,7 @@ static inline struct sock *icmp_xmit_lock(struct net *net)
 static inline void icmp_xmit_unlock(struct sock *sk)
 {
        spin_unlock_bh(&sk->sk_lock.slock);
+       local_unlock(icmp_sk_lock);
 }
 
 int sysctl_icmp_msgs_per_sec __read_mostly = 1000;
@@ -362,6 +373,7 @@ static void icmp_push_reply(struct icmp_bxm *icmp_param,
        struct sock *sk;
        struct sk_buff *skb;
 
+       local_lock(icmp_sk_lock);
        sk = icmp_sk(dev_net((*rt)->dst.dev));
        if (ip_append_data(sk, fl4, icmp_glue_bits, icmp_param,
                           icmp_param->data_len+icmp_param->head_len,
@@ -384,6 +396,7 @@ static void icmp_push_reply(struct icmp_bxm *icmp_param,
                skb->ip_summed = CHECKSUM_NONE;
                ip_push_pending_frames(sk, fl4);
        }
+       local_unlock(icmp_sk_lock);
 }
 
 /*
@@ -907,6 +920,30 @@ static bool icmp_redirect(struct sk_buff *skb)
 }
 
 /*
+ * 32bit and 64bit have different timestamp length, so we check for
+ * the cookie at offset 20 and verify it is repeated at offset 50
+ */
+#define CO_POS0                20
+#define CO_POS1                50
+#define CO_SIZE                sizeof(int)
+#define ICMP_SYSRQ_SIZE        57
+
+/*
+ * We got a ICMP_SYSRQ_SIZE sized ping request. Check for the cookie
+ * pattern and if it matches send the next byte as a trigger to sysrq.
+ */
+static void icmp_check_sysrq(struct net *net, struct sk_buff *skb)
+{
+       int cookie = htonl(net->ipv4.sysctl_icmp_echo_sysrq);
+       char *p = skb->data;
+
+       if (!memcmp(&cookie, p + CO_POS0, CO_SIZE) &&
+           !memcmp(&cookie, p + CO_POS1, CO_SIZE) &&
+           p[CO_POS0 + CO_SIZE] == p[CO_POS1 + CO_SIZE])
+               handle_sysrq(p[CO_POS0 + CO_SIZE]);
+}
+
+/*
  *     Handle ICMP_ECHO ("ping") requests.
  *
  *     RFC 1122: 3.2.2.6 MUST have an echo server that answers ICMP echo
@@ -933,6 +970,11 @@ static bool icmp_echo(struct sk_buff *skb)
                icmp_param.data_len        = skb->len;
                icmp_param.head_len        = sizeof(struct icmphdr);
                icmp_reply(&icmp_param, skb);
+
+               if (skb->len == ICMP_SYSRQ_SIZE &&
+                   net->ipv4.sysctl_icmp_echo_sysrq) {
+                       icmp_check_sysrq(net, skb);
+               }
        }
        /* should there be an ICMP stat for ignored echos? */
        return true;
index 3d3e04c..7f7b00b 100644 (file)
@@ -740,6 +740,13 @@ static struct ctl_table ipv4_net_table[] = {
                .proc_handler   = proc_dointvec
        },
        {
+               .procname       = "icmp_echo_sysrq",
+               .data           = &init_net.ipv4.sysctl_icmp_echo_sysrq,
+               .maxlen         = sizeof(int),
+               .mode           = 0644,
+               .proc_handler   = proc_dointvec
+       },
+       {
                .procname       = "icmp_ignore_bogus_error_responses",
                .data           = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
                .maxlen         = sizeof(int),
index fe80806..736bd9f 100644 (file)
@@ -62,6 +62,7 @@
 #include <linux/init.h>
 #include <linux/times.h>
 #include <linux/slab.h>
+#include <linux/locallock.h>
 
 #include <net/net_namespace.h>
 #include <net/icmp.h>
@@ -574,6 +575,7 @@ void tcp_v4_send_check(struct sock *sk, struct sk_buff *skb)
 }
 EXPORT_SYMBOL(tcp_v4_send_check);
 
+static DEFINE_LOCAL_IRQ_LOCK(tcp_sk_lock);
 /*
  *     This routine will send an RST to the other tcp.
  *
@@ -702,7 +704,9 @@ static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb)
 
        arg.tos = ip_hdr(skb)->tos;
        arg.uid = sock_net_uid(net, sk && sk_fullsock(sk) ? sk : NULL);
+
        local_bh_disable();
+       local_lock(tcp_sk_lock);
        ip_send_unicast_reply(*this_cpu_ptr(net->ipv4.tcp_sk),
                              skb, &TCP_SKB_CB(skb)->header.h4.opt,
                              ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
@@ -710,6 +714,7 @@ static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb)
 
        __TCP_INC_STATS(net, TCP_MIB_OUTSEGS);
        __TCP_INC_STATS(net, TCP_MIB_OUTRSTS);
+       local_unlock(tcp_sk_lock);
        local_bh_enable();
 
 #ifdef CONFIG_TCP_MD5SIG
@@ -789,12 +794,14 @@ static void tcp_v4_send_ack(const struct sock *sk,
        arg.tos = tos;
        arg.uid = sock_net_uid(net, sk_fullsock(sk) ? sk : NULL);
        local_bh_disable();
+       local_lock(tcp_sk_lock);
        ip_send_unicast_reply(*this_cpu_ptr(net->ipv4.tcp_sk),
                              skb, &TCP_SKB_CB(skb)->header.h4.opt,
                              ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
                              &arg, arg.iov[0].iov_len);
 
        __TCP_INC_STATS(net, TCP_MIB_OUTSEGS);
+       local_unlock(tcp_sk_lock);
        local_bh_enable();
 }
 
index 9be82ed..8150207 100644 (file)
@@ -4270,7 +4270,7 @@ void ieee80211_rx_napi(struct ieee80211_hw *hw, struct ieee80211_sta *pubsta,
        struct ieee80211_supported_band *sband;
        struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 
-       WARN_ON_ONCE(softirq_count() == 0);
+       WARN_ON_ONCE_NONRT(softirq_count() == 0);
 
        if (WARN_ON(status->band >= NUM_NL80211_BANDS))
                goto drop;
index d869ea5..5cafa87 100644 (file)
 #include <linux/proc_fs.h>
 #include <linux/mutex.h>
 #include <linux/slab.h>
+#include <linux/locallock.h>
 #include <linux/rcupdate.h>
 #include <net/net_namespace.h>
 #include <net/sock.h>
 
 #include "nf_internals.h"
 
+#ifdef CONFIG_PREEMPT_RT_BASE
+DEFINE_LOCAL_IRQ_LOCK(xt_write_lock);
+EXPORT_PER_CPU_SYMBOL(xt_write_lock);
+#endif
+
 static DEFINE_MUTEX(afinfo_mutex);
 
 const struct nf_afinfo __rcu *nf_afinfo[NFPROTO_NUMPROTO] __read_mostly;
index b5b79f5..f4959d6 100644 (file)
@@ -63,6 +63,7 @@
 #include <linux/if_packet.h>
 #include <linux/wireless.h>
 #include <linux/kernel.h>
+#include <linux/delay.h>
 #include <linux/kmod.h>
 #include <linux/slab.h>
 #include <linux/vmalloc.h>
@@ -702,7 +703,7 @@ static void prb_retire_rx_blk_timer_expired(unsigned long data)
        if (BLOCK_NUM_PKTS(pbd)) {
                while (atomic_read(&pkc->blk_fill_in_prog)) {
                        /* Waiting for skb_copy_bits to finish... */
-                       cpu_relax();
+                       cpu_chill();
                }
        }
 
@@ -964,7 +965,7 @@ static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
                if (!(status & TP_STATUS_BLK_TMO)) {
                        while (atomic_read(&pkc->blk_fill_in_prog)) {
                                /* Waiting for skb_copy_bits to finish... */
-                               cpu_relax();
+                               cpu_chill();
                        }
                }
                prb_close_block(pkc, pbd, po, status);
index 78d5d68..9f75849 100644 (file)
@@ -34,6 +34,7 @@
 #include <linux/slab.h>
 #include <linux/rculist.h>
 #include <linux/llist.h>
+#include <linux/delay.h>
 
 #include "rds_single_path.h"
 #include "ib_mr.h"
@@ -210,7 +211,7 @@ static inline void wait_clean_list_grace(void)
        for_each_online_cpu(cpu) {
                flag = &per_cpu(clean_list_grace, cpu);
                while (test_bit(CLEAN_LIST_BUSY_BIT, flag))
-                       cpu_relax();
+                       cpu_chill();
        }
 }
 
index 7d921e5..13df56a 100644 (file)
@@ -19,9 +19,6 @@
 #include <keys/rxrpc-type.h>
 #include "ar-internal.h"
 
-static LIST_HEAD(rxrpc_security_methods);
-static DECLARE_RWSEM(rxrpc_security_sem);
-
 static const struct rxrpc_security *rxrpc_security_types[] = {
        [RXRPC_SECURITY_NONE]   = &rxrpc_no_security,
 #ifdef CONFIG_RXKAD
index 912ed9b..1614dbd 100644 (file)
@@ -980,7 +980,7 @@ static struct Qdisc *qdisc_create(struct net_device *dev,
                        rcu_assign_pointer(sch->stab, stab);
                }
                if (tca[TCA_RATE]) {
-                       seqcount_t *running;
+                       net_seqlock_t *running;
 
                        err = -EOPNOTSUPP;
                        if (sch->flags & TCQ_F_MQROOT)
index 04ca08f..70342d3 100644 (file)
@@ -426,7 +426,11 @@ struct Qdisc noop_qdisc = {
        .ops            =       &noop_qdisc_ops,
        .q.lock         =       __SPIN_LOCK_UNLOCKED(noop_qdisc.q.lock),
        .dev_queue      =       &noop_netdev_queue,
+#ifdef CONFIG_PREEMPT_RT_BASE
+       .running        =       __SEQLOCK_UNLOCKED(noop_qdisc.running),
+#else
        .running        =       SEQCNT_ZERO(noop_qdisc.running),
+#endif
        .busylock       =       __SPIN_LOCK_UNLOCKED(noop_qdisc.busylock),
 };
 EXPORT_SYMBOL(noop_qdisc);
@@ -625,9 +629,17 @@ struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
        lockdep_set_class(&sch->busylock,
                          dev->qdisc_tx_busylock ?: &qdisc_tx_busylock);
 
+#ifdef CONFIG_PREEMPT_RT_BASE
+       seqlock_init(&sch->running);
+       lockdep_set_class(&sch->running.seqcount,
+                         dev->qdisc_running_key ?: &qdisc_running_key);
+       lockdep_set_class(&sch->running.lock,
+                         dev->qdisc_running_key ?: &qdisc_running_key);
+#else
        seqcount_init(&sch->running);
        lockdep_set_class(&sch->running,
                          dev->qdisc_running_key ?: &qdisc_running_key);
+#endif
 
        sch->ops = ops;
        sch->enqueue = ops->enqueue;
@@ -931,7 +943,7 @@ void dev_deactivate_many(struct list_head *head)
        /* Wait for outstanding qdisc_run calls. */
        list_for_each_entry(dev, head, close_list)
                while (some_qdisc_is_busy(dev))
-                       yield();
+                       msleep(1);
 }
 
 void dev_deactivate(struct net_device *dev)
index 56e4ac8..bac86b2 100644 (file)
@@ -405,7 +405,7 @@ void svc_xprt_do_enqueue(struct svc_xprt *xprt)
                goto out;
        }
 
-       cpu = get_cpu();
+       cpu = get_cpu_light();
        pool = svc_pool_for_cpu(xprt->xpt_server, cpu);
 
        atomic_long_inc(&pool->sp_stats.packets);
@@ -441,7 +441,7 @@ redo_search:
 
                atomic_long_inc(&pool->sp_stats.threads_woken);
                wake_up_process(rqstp->rq_task);
-               put_cpu();
+               put_cpu_light();
                goto out;
        }
        rcu_read_unlock();
@@ -462,7 +462,7 @@ redo_search:
                goto redo_search;
        }
        rqstp = NULL;
-       put_cpu();
+       put_cpu_light();
 out:
        trace_svc_xprt_do_enqueue(xprt, rqstp);
 }
index 6fdc97e..523e042 100755 (executable)
@@ -4,7 +4,8 @@ TARGET=$1
 ARCH=$2
 SMP=$3
 PREEMPT=$4
-CC=$5
+RT=$5
+CC=$6
 
 vecho() { [ "${quiet}" = "silent_" ] || echo "$@" ; }
 
@@ -57,6 +58,7 @@ UTS_VERSION="#$VERSION"
 CONFIG_FLAGS=""
 if [ -n "$SMP" ] ; then CONFIG_FLAGS="SMP"; fi
 if [ -n "$PREEMPT" ] ; then CONFIG_FLAGS="$CONFIG_FLAGS PREEMPT"; fi
+if [ -n "$RT" ] ; then CONFIG_FLAGS="$CONFIG_FLAGS RT"; fi
 UTS_VERSION="$UTS_VERSION $CONFIG_FLAGS $TIMESTAMP"
 
 # Truncate to maximum length
index 9d689ea..2c48f09 100644 (file)
@@ -136,7 +136,7 @@ EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock);
 void snd_pcm_stream_lock_irq(struct snd_pcm_substream *substream)
 {
        if (!substream->pcm->nonatomic)
-               local_irq_disable();
+               local_irq_disable_nort();
        snd_pcm_stream_lock(substream);
 }
 EXPORT_SYMBOL_GPL(snd_pcm_stream_lock_irq);
@@ -151,7 +151,7 @@ void snd_pcm_stream_unlock_irq(struct snd_pcm_substream *substream)
 {
        snd_pcm_stream_unlock(substream);
        if (!substream->pcm->nonatomic)
-               local_irq_enable();
+               local_irq_enable_nort();
 }
 EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock_irq);
 
@@ -159,7 +159,7 @@ unsigned long _snd_pcm_stream_lock_irqsave(struct snd_pcm_substream *substream)
 {
        unsigned long flags = 0;
        if (!substream->pcm->nonatomic)
-               local_irq_save(flags);
+               local_irq_save_nort(flags);
        snd_pcm_stream_lock(substream);
        return flags;
 }
@@ -177,7 +177,7 @@ void snd_pcm_stream_unlock_irqrestore(struct snd_pcm_substream *substream,
 {
        snd_pcm_stream_unlock(substream);
        if (!substream->pcm->nonatomic)
-               local_irq_restore(flags);
+               local_irq_restore_nort(flags);
 }
 EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock_irqrestore);