patch-5.10.100-rt62.patch 59/271959/1
authorLuis Claudio R. Goncalves <lclaudio@uudg.org>
Fri, 18 Feb 2022 13:33:21 +0000 (14:33 +0100)
committerŁukasz Stelmach <l.stelmach@samsung.com>
Fri, 4 Mar 2022 01:33:00 +0000 (02:33 +0100)
Apply PREEMPT_RT patch 5.10.100-rt62.

Change-Id: Ifc945830d28bb3ac251e611043cc625e656eceda
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
425 files changed:
Documentation/RCU/Design/Expedited-Grace-Periods/Expedited-Grace-Periods.rst
Documentation/RCU/Design/Requirements/Requirements.rst
Documentation/RCU/checklist.rst
Documentation/RCU/rcubarrier.rst
Documentation/RCU/stallwarn.rst
Documentation/RCU/whatisRCU.rst
Documentation/admin-guide/kernel-parameters.txt
Documentation/driver-api/io-mapping.rst
arch/Kconfig
arch/alpha/include/asm/kmap_types.h [deleted file]
arch/alpha/include/asm/spinlock_types.h
arch/arc/Kconfig
arch/arc/include/asm/highmem.h
arch/arc/include/asm/kmap_types.h [deleted file]
arch/arc/mm/highmem.c
arch/arm/Kconfig
arch/arm/include/asm/fixmap.h
arch/arm/include/asm/hardirq.h
arch/arm/include/asm/highmem.h
arch/arm/include/asm/irq.h
arch/arm/include/asm/kmap_types.h [deleted file]
arch/arm/include/asm/spinlock_types.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/signal.c
arch/arm/kernel/smp.c
arch/arm/mm/Makefile
arch/arm/mm/cache-feroceon-l2.c
arch/arm/mm/cache-xsc3l2.c
arch/arm/mm/fault.c
arch/arm/mm/highmem.c [deleted file]
arch/arm64/Kconfig
arch/arm64/include/asm/hardirq.h
arch/arm64/include/asm/preempt.h
arch/arm64/include/asm/spinlock_types.h
arch/arm64/include/asm/thread_info.h
arch/arm64/kernel/asm-offsets.c
arch/arm64/kernel/entry.S
arch/arm64/kernel/fpsimd.c
arch/arm64/kernel/signal.c
arch/arm64/kvm/arm.c
arch/csky/Kconfig
arch/csky/include/asm/fixmap.h
arch/csky/include/asm/highmem.h
arch/csky/mm/highmem.c
arch/hexagon/include/asm/spinlock_types.h
arch/ia64/include/asm/kmap_types.h [deleted file]
arch/ia64/include/asm/spinlock_types.h
arch/ia64/kernel/time.c
arch/microblaze/Kconfig
arch/microblaze/include/asm/fixmap.h
arch/microblaze/include/asm/highmem.h
arch/microblaze/mm/Makefile
arch/microblaze/mm/highmem.c [deleted file]
arch/microblaze/mm/init.c
arch/mips/Kconfig
arch/mips/include/asm/fixmap.h
arch/mips/include/asm/highmem.h
arch/mips/include/asm/kmap_types.h [deleted file]
arch/mips/kernel/crash_dump.c
arch/mips/mm/highmem.c
arch/mips/mm/init.c
arch/nds32/Kconfig.cpu
arch/nds32/include/asm/fixmap.h
arch/nds32/include/asm/highmem.h
arch/nds32/mm/Makefile
arch/nds32/mm/highmem.c [deleted file]
arch/openrisc/mm/init.c
arch/openrisc/mm/ioremap.c
arch/parisc/include/asm/hardirq.h
arch/parisc/include/asm/kmap_types.h [deleted file]
arch/powerpc/Kconfig
arch/powerpc/include/asm/cmpxchg.h
arch/powerpc/include/asm/fixmap.h
arch/powerpc/include/asm/highmem.h
arch/powerpc/include/asm/kmap_types.h [deleted file]
arch/powerpc/include/asm/simple_spinlock_types.h
arch/powerpc/include/asm/spinlock_types.h
arch/powerpc/include/asm/stackprotector.h
arch/powerpc/include/asm/thread_info.h
arch/powerpc/kernel/asm-offsets.c
arch/powerpc/kernel/entry_32.S
arch/powerpc/kernel/exceptions-64e.S
arch/powerpc/kernel/irq.c
arch/powerpc/kernel/misc_32.S
arch/powerpc/kernel/misc_64.S
arch/powerpc/kernel/nvram_64.c
arch/powerpc/kernel/syscall_64.c
arch/powerpc/kernel/time.c
arch/powerpc/kernel/traps.c
arch/powerpc/kernel/watchdog.c
arch/powerpc/kexec/crash.c
arch/powerpc/kvm/Kconfig
arch/powerpc/mm/Makefile
arch/powerpc/mm/highmem.c [deleted file]
arch/powerpc/mm/mem.c
arch/powerpc/platforms/powernv/opal-kmsg.c
arch/powerpc/platforms/pseries/iommu.c
arch/powerpc/xmon/xmon.c
arch/s390/Kconfig
arch/s390/include/asm/spinlock_types.h
arch/s390/include/asm/vtime.h
arch/s390/kernel/vtime.c
arch/sh/include/asm/fixmap.h
arch/sh/include/asm/hardirq.h
arch/sh/include/asm/kmap_types.h [deleted file]
arch/sh/include/asm/spinlock_types.h
arch/sh/kernel/irq.c
arch/sh/kernel/traps.c
arch/sh/mm/init.c
arch/sparc/Kconfig
arch/sparc/include/asm/highmem.h
arch/sparc/include/asm/kmap_types.h [deleted file]
arch/sparc/include/asm/vaddrs.h
arch/sparc/kernel/irq_64.c
arch/sparc/mm/Makefile
arch/sparc/mm/highmem.c [deleted file]
arch/sparc/mm/srmmu.c
arch/um/include/asm/fixmap.h
arch/um/include/asm/hardirq.h
arch/um/include/asm/kmap_types.h [deleted file]
arch/um/kernel/kmsg_dump.c
arch/x86/Kconfig
arch/x86/crypto/aesni-intel_glue.c
arch/x86/crypto/cast5_avx_glue.c
arch/x86/crypto/glue_helper.c
arch/x86/include/asm/fixmap.h
arch/x86/include/asm/fpu/api.h
arch/x86/include/asm/highmem.h
arch/x86/include/asm/iomap.h
arch/x86/include/asm/kmap_types.h [deleted file]
arch/x86/include/asm/paravirt_types.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/kernel/cpu/mshyperv.c
arch/x86/kernel/crash_dump_32.c
arch/x86/kernel/fpu/core.c
arch/x86/kernel/irq_32.c
arch/x86/kernel/irq_64.c
arch/x86/kvm/x86.c
arch/x86/mm/highmem_32.c
arch/x86/mm/init_32.c
arch/x86/mm/iomap_32.c
arch/xtensa/Kconfig
arch/xtensa/include/asm/fixmap.h
arch/xtensa/include/asm/highmem.h
arch/xtensa/include/asm/spinlock_types.h
arch/xtensa/mm/highmem.c
block/blk-mq.c
crypto/cryptd.c
drivers/atm/eni.c
drivers/block/zram/zram_drv.c
drivers/block/zram/zram_drv.h
drivers/char/random.c
drivers/char/tpm/tpm-dev-common.c
drivers/char/tpm/tpm_tis.c
drivers/firewire/ohci.c
drivers/firmware/efi/efi.c
drivers/gpu/drm/i915/display/intel_sprite.c
drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
drivers/gpu/drm/i915/gt/intel_breadcrumbs.c
drivers/gpu/drm/i915/gt/intel_engine_pm.c
drivers/gpu/drm/i915/i915_gem.c
drivers/gpu/drm/i915/i915_irq.c
drivers/gpu/drm/i915/i915_trace.h
drivers/gpu/drm/i915/selftests/i915_gem.c
drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
drivers/gpu/drm/nouveau/nvkm/subdev/devinit/fbmem.h
drivers/gpu/drm/qxl/qxl_image.c
drivers/gpu/drm/qxl/qxl_ioctl.c
drivers/gpu/drm/qxl/qxl_object.c
drivers/gpu/drm/qxl/qxl_object.h
drivers/gpu/drm/qxl/qxl_release.c
drivers/gpu/drm/radeon/radeon_display.c
drivers/gpu/drm/ttm/ttm_bo_util.c
drivers/gpu/drm/vmwgfx/vmwgfx_blit.c
drivers/hv/hyperv_vmbus.h
drivers/hv/vmbus_drv.c
drivers/leds/trigger/Kconfig
drivers/md/raid5.c
drivers/md/raid5.h
drivers/mtd/mtdoops.c
drivers/net/arcnet/arc-rimi.c
drivers/net/arcnet/arcdevice.h
drivers/net/arcnet/arcnet.c
drivers/net/arcnet/com20020-isa.c
drivers/net/arcnet/com20020-pci.c
drivers/net/arcnet/com20020_cs.c
drivers/net/arcnet/com90io.c
drivers/net/arcnet/com90xx.c
drivers/net/ethernet/chelsio/cxgb/common.h
drivers/net/ethernet/chelsio/cxgb/cxgb2.c
drivers/net/ethernet/chelsio/cxgb/sge.c
drivers/net/ethernet/chelsio/cxgb/sge.h
drivers/net/ethernet/chelsio/cxgb/subr.c
drivers/net/ethernet/dlink/sundance.c
drivers/net/ethernet/jme.c
drivers/net/ethernet/jme.h
drivers/net/wireless/ath/ath9k/beacon.c
drivers/pci/controller/pci-hyperv.c
drivers/scsi/fcoe/fcoe.c
drivers/scsi/fcoe/fcoe_ctlr.c
drivers/scsi/libfc/fc_exch.c
drivers/tty/serial/8250/8250.h
drivers/tty/serial/8250/8250_core.c
drivers/tty/serial/8250/8250_fsl.c
drivers/tty/serial/8250/8250_ingenic.c
drivers/tty/serial/8250/8250_mtk.c
drivers/tty/serial/8250/8250_port.c
drivers/tty/serial/amba-pl011.c
drivers/tty/serial/omap-serial.c
fs/afs/dir_silly.c
fs/aio.c
fs/btrfs/ctree.h
fs/cifs/readdir.c
fs/dcache.c
fs/eventfd.c
fs/fscache/internal.h
fs/fscache/main.c
fs/fscache/object.c
fs/fuse/readdir.c
fs/inode.c
fs/namei.c
fs/namespace.c
fs/nfs/dir.c
fs/nfs/unlink.c
fs/proc/array.c
fs/proc/base.c
fs/proc/proc_sysctl.c
fs/pstore/platform.c
include/asm-generic/Kbuild
include/asm-generic/hardirq.h
include/asm-generic/kmap_size.h [new file with mode: 0644]
include/asm-generic/kmap_types.h [deleted file]
include/asm-generic/preempt.h
include/linux/blkdev.h
include/linux/bottom_half.h
include/linux/console.h
include/linux/cpuhotplug.h
include/linux/cpumask.h
include/linux/dcache.h
include/linux/debug_locks.h
include/linux/delay.h
include/linux/entry-common.h
include/linux/eventfd.h
include/linux/fs.h
include/linux/hardirq.h
include/linux/highmem-internal.h [new file with mode: 0644]
include/linux/highmem.h
include/linux/interrupt.h
include/linux/io-mapping.h
include/linux/irq_cpustat.h [deleted file]
include/linux/irq_work.h
include/linux/irqdesc.h
include/linux/irqflags.h
include/linux/kernel.h
include/linux/kmsg_dump.h
include/linux/local_lock_internal.h
include/linux/mm_types.h
include/linux/mutex.h
include/linux/mutex_rt.h [new file with mode: 0644]
include/linux/nfs_xdr.h
include/linux/notifier.h
include/linux/pid.h
include/linux/preempt.h
include/linux/printk.h
include/linux/random.h
include/linux/rbtree.h
include/linux/rbtree_type.h [new file with mode: 0644]
include/linux/rcupdate.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-rt.h [new file with mode: 0644]
include/linux/rwsem.h
include/linux/sched.h
include/linux/sched/hotplug.h
include/linux/sched/mm.h
include/linux/sched/rt.h
include/linux/sched/wake_q.h
include/linux/serial_8250.h
include/linux/shmem_fs.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/spinlock_types_up.h
include/linux/stop_machine.h
include/linux/thread_info.h
include/linux/trace_events.h
include/linux/u64_stats_sync.h
include/linux/vmstat.h
include/linux/vtime.h
include/linux/wait.h
include/linux/ww_mutex.h
include/net/gen_stats.h
include/net/net_seq_lock.h [new file with mode: 0644]
include/net/netns/xfrm.h
include/net/sch_generic.h
include/trace/events/sched.h
init/Kconfig
kernel/Kconfig.locks
kernel/Kconfig.preempt
kernel/cgroup/cpuset.c
kernel/cgroup/rstat.c
kernel/cpu.c
kernel/debug/kdb/kdb_main.c
kernel/entry/common.c
kernel/exit.c
kernel/fork.c
kernel/futex.c
kernel/irq/handle.c
kernel/irq/manage.c
kernel/irq/spurious.c
kernel/irq_work.c
kernel/kexec_core.c
kernel/ksysfs.c
kernel/kthread.c
kernel/locking/Makefile
kernel/locking/lockdep.c
kernel/locking/mutex-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/rwlock-rt.c [new file with mode: 0644]
kernel/locking/rwsem-rt.c [new file with mode: 0644]
kernel/locking/rwsem.c
kernel/locking/spinlock.c
kernel/locking/spinlock_debug.c
kernel/notifier.c
kernel/panic.c
kernel/printk/Makefile
kernel/printk/internal.h [deleted file]
kernel/printk/printk.c
kernel/printk/printk_safe.c [deleted file]
kernel/ptrace.c
kernel/rcu/Kconfig
kernel/rcu/tree.c
kernel/rcu/update.c
kernel/sched/core.c
kernel/sched/cpudeadline.c
kernel/sched/cpupri.c
kernel/sched/cputime.c
kernel/sched/deadline.c
kernel/sched/fair.c
kernel/sched/features.h
kernel/sched/rt.c
kernel/sched/sched.h
kernel/sched/swait.c
kernel/sched/topology.c
kernel/signal.c
kernel/smp.c
kernel/softirq.c
kernel/stop_machine.c
kernel/time/hrtimer.c
kernel/time/tick-sched.c
kernel/time/timer.c
kernel/trace/blktrace.c
kernel/trace/trace.c
kernel/trace/trace.h
kernel/trace/trace_branch.c
kernel/trace/trace_event_perf.c
kernel/trace/trace_events.c
kernel/trace/trace_events_inject.c
kernel/trace/trace_functions.c
kernel/trace/trace_functions_graph.c
kernel/trace/trace_hwlat.c
kernel/trace/trace_irqsoff.c
kernel/trace/trace_kprobe.c
kernel/trace/trace_mmiotrace.c
kernel/trace/trace_output.c
kernel/trace/trace_sched_wakeup.c
kernel/trace/trace_syscalls.c
kernel/trace/trace_uprobe.c
kernel/workqueue.c
lib/Kconfig.debug
lib/bug.c
lib/cpumask.c
lib/debugobjects.c
lib/dump_stack.c
lib/irq_poll.c
lib/locking-selftest.c
lib/nmi_backtrace.c
lib/scatterlist.c
lib/smp_processor_id.c
lib/test_lockup.c
localversion-rt [new file with mode: 0644]
mm/Kconfig
mm/highmem.c
mm/memcontrol.c
mm/page_alloc.c
mm/shmem.c
mm/slab.c
mm/slab.h
mm/slub.c
mm/vmalloc.c
mm/vmstat.c
mm/workingset.c
mm/z3fold.c
mm/zsmalloc.c
mm/zswap.c
net/Kconfig
net/core/dev.c
net/core/gen_estimator.c
net/core/gen_stats.c
net/core/sock.c
net/ipv4/inet_hashtables.c
net/ipv6/inet6_hashtables.c
net/sched/sch_api.c
net/sched/sch_generic.c
net/sunrpc/svc_xprt.c
net/xfrm/xfrm_state.c

index 72f0f6f..6f89cf1 100644 (file)
@@ -38,7 +38,7 @@ sections.
 RCU-preempt Expedited Grace Periods
 ===================================
 
-``CONFIG_PREEMPT=y`` kernels implement RCU-preempt.
+``CONFIG_PREEMPTION=y`` kernels implement RCU-preempt.
 The overall flow of the handling of a given CPU by an RCU-preempt
 expedited grace period is shown in the following diagram:
 
@@ -112,7 +112,7 @@ things.
 RCU-sched Expedited Grace Periods
 ---------------------------------
 
-``CONFIG_PREEMPT=n`` kernels implement RCU-sched. The overall flow of
+``CONFIG_PREEMPTION=n`` kernels implement RCU-sched. The overall flow of
 the handling of a given CPU by an RCU-sched expedited grace period is
 shown in the following diagram:
 
index 1ae79a1..17d3848 100644 (file)
@@ -78,7 +78,7 @@ RCU treats a nested set as one big RCU read-side critical section.
 Production-quality implementations of ``rcu_read_lock()`` and
 ``rcu_read_unlock()`` are extremely lightweight, and in fact have
 exactly zero overhead in Linux kernels built for production use with
-``CONFIG_PREEMPT=n``.
+``CONFIG_PREEMPTION=n``.
 
 This guarantee allows ordering to be enforced with extremely low
 overhead to readers, for example:
@@ -1182,7 +1182,7 @@ and has become decreasingly so as memory sizes have expanded and memory
 costs have plummeted. However, as I learned from Matt Mackall's
 `bloatwatch <http://elinux.org/Linux_Tiny-FAQ>`__ efforts, memory
 footprint is critically important on single-CPU systems with
-non-preemptible (``CONFIG_PREEMPT=n``) kernels, and thus `tiny
+non-preemptible (``CONFIG_PREEMPTION=n``) kernels, and thus `tiny
 RCU <https://lkml.kernel.org/g/20090113221724.GA15307@linux.vnet.ibm.com>`__
 was born. Josh Triplett has since taken over the small-memory banner
 with his `Linux kernel tinification <https://tiny.wiki.kernel.org/>`__
@@ -1498,7 +1498,7 @@ limitations.
 
 Implementations of RCU for which ``rcu_read_lock()`` and
 ``rcu_read_unlock()`` generate no code, such as Linux-kernel RCU when
-``CONFIG_PREEMPT=n``, can be nested arbitrarily deeply. After all, there
+``CONFIG_PREEMPTION=n``, can be nested arbitrarily deeply. After all, there
 is no overhead. Except that if all these instances of
 ``rcu_read_lock()`` and ``rcu_read_unlock()`` are visible to the
 compiler, compilation will eventually fail due to exhausting memory,
@@ -1771,7 +1771,7 @@ implementation can be a no-op.
 
 However, once the scheduler has spawned its first kthread, this early
 boot trick fails for ``synchronize_rcu()`` (as well as for
-``synchronize_rcu_expedited()``) in ``CONFIG_PREEMPT=y`` kernels. The
+``synchronize_rcu_expedited()``) in ``CONFIG_PREEMPTION=y`` kernels. The
 reason is that an RCU read-side critical section might be preempted,
 which means that a subsequent ``synchronize_rcu()`` really does have to
 wait for something, as opposed to simply returning immediately.
@@ -2010,7 +2010,7 @@ the following:
        5 rcu_read_unlock();
        6 do_something_with(v, user_v);
 
-If the compiler did make this transformation in a ``CONFIG_PREEMPT=n`` kernel
+If the compiler did make this transformation in a ``CONFIG_PREEMPTION=n`` kernel
 build, and if ``get_user()`` did page fault, the result would be a quiescent
 state in the middle of an RCU read-side critical section.  This misplaced
 quiescent state could result in line 4 being a use-after-free access,
@@ -2289,10 +2289,10 @@ decides to throw at it.
 
 The Linux kernel is used for real-time workloads, especially in
 conjunction with the `-rt
-patchset <https://rt.wiki.kernel.org/index.php/Main_Page>`__. The
+patchset <https://wiki.linuxfoundation.org/realtime/>`__. The
 real-time-latency response requirements are such that the traditional
 approach of disabling preemption across RCU read-side critical sections
-is inappropriate. Kernels built with ``CONFIG_PREEMPT=y`` therefore use
+is inappropriate. Kernels built with ``CONFIG_PREEMPTION=y`` therefore use
 an RCU implementation that allows RCU read-side critical sections to be
 preempted. This requirement made its presence known after users made it
 clear that an earlier `real-time
@@ -2414,7 +2414,7 @@ includes ``rcu_read_lock_bh()``, ``rcu_read_unlock_bh()``,
 ``call_rcu_bh()``, ``rcu_barrier_bh()``, and
 ``rcu_read_lock_bh_held()``. However, the update-side APIs are now
 simple wrappers for other RCU flavors, namely RCU-sched in
-CONFIG_PREEMPT=n kernels and RCU-preempt otherwise.
+CONFIG_PREEMPTION=n kernels and RCU-preempt otherwise.
 
 Sched Flavor (Historical)
 ~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -2432,11 +2432,11 @@ not have this property, given that any point in the code outside of an
 RCU read-side critical section can be a quiescent state. Therefore,
 *RCU-sched* was created, which follows “classic” RCU in that an
 RCU-sched grace period waits for pre-existing interrupt and NMI
-handlers. In kernels built with ``CONFIG_PREEMPT=n``, the RCU and
+handlers. In kernels built with ``CONFIG_PREEMPTION=n``, the RCU and
 RCU-sched APIs have identical implementations, while kernels built with
-``CONFIG_PREEMPT=y`` provide a separate implementation for each.
+``CONFIG_PREEMPTION=y`` provide a separate implementation for each.
 
-Note well that in ``CONFIG_PREEMPT=y`` kernels,
+Note well that in ``CONFIG_PREEMPTION=y`` kernels,
 ``rcu_read_lock_sched()`` and ``rcu_read_unlock_sched()`` disable and
 re-enable preemption, respectively. This means that if there was a
 preemption attempt during the RCU-sched read-side critical section,
@@ -2599,10 +2599,10 @@ userspace execution also delimit tasks-RCU read-side critical sections.
 
 The tasks-RCU API is quite compact, consisting only of
 ``call_rcu_tasks()``, ``synchronize_rcu_tasks()``, and
-``rcu_barrier_tasks()``. In ``CONFIG_PREEMPT=n`` kernels, trampolines
+``rcu_barrier_tasks()``. In ``CONFIG_PREEMPTION=n`` kernels, trampolines
 cannot be preempted, so these APIs map to ``call_rcu()``,
 ``synchronize_rcu()``, and ``rcu_barrier()``, respectively. In
-``CONFIG_PREEMPT=y`` kernels, trampolines can be preempted, and these
+``CONFIG_PREEMPTION=y`` kernels, trampolines can be preempted, and these
 three APIs are therefore implemented by separate functions that check
 for voluntary context switches.
 
index 2efed99..7ed4956 100644 (file)
@@ -214,7 +214,7 @@ over a rather long period of time, but improvements are always welcome!
        the rest of the system.
 
 7.     As of v4.20, a given kernel implements only one RCU flavor,
-       which is RCU-sched for PREEMPT=n and RCU-preempt for PREEMPT=y.
+       which is RCU-sched for PREEMPTION=n and RCU-preempt for PREEMPTION=y.
        If the updater uses call_rcu() or synchronize_rcu(),
        then the corresponding readers my use rcu_read_lock() and
        rcu_read_unlock(), rcu_read_lock_bh() and rcu_read_unlock_bh(),
index f64f441..3b4a248 100644 (file)
@@ -9,7 +9,7 @@ RCU (read-copy update) is a synchronization mechanism that can be thought
 of as a replacement for read-writer locking (among other things), but with
 very low-overhead readers that are immune to deadlock, priority inversion,
 and unbounded latency. RCU read-side critical sections are delimited
-by rcu_read_lock() and rcu_read_unlock(), which, in non-CONFIG_PREEMPT
+by rcu_read_lock() and rcu_read_unlock(), which, in non-CONFIG_PREEMPTION
 kernels, generate no code whatsoever.
 
 This means that RCU writers are unaware of the presence of concurrent
@@ -329,10 +329,10 @@ Answer: This cannot happen. The reason is that on_each_cpu() has its last
        to smp_call_function() and further to smp_call_function_on_cpu(),
        causing this latter to spin until the cross-CPU invocation of
        rcu_barrier_func() has completed. This by itself would prevent
-       a grace period from completing on non-CONFIG_PREEMPT kernels,
+       a grace period from completing on non-CONFIG_PREEMPTION kernels,
        since each CPU must undergo a context switch (or other quiescent
        state) before the grace period can complete. However, this is
-       of no use in CONFIG_PREEMPT kernels.
+       of no use in CONFIG_PREEMPTION kernels.
 
        Therefore, on_each_cpu() disables preemption across its call
        to smp_call_function() and also across the local call to
index c9ab6af..e97d1b4 100644 (file)
@@ -25,7 +25,7 @@ warnings:
 
 -      A CPU looping with bottom halves disabled.
 
--      For !CONFIG_PREEMPT kernels, a CPU looping anywhere in the kernel
+-      For !CONFIG_PREEMPTION kernels, a CPU looping anywhere in the kernel
        without invoking schedule().  If the looping in the kernel is
        really expected and desirable behavior, you might need to add
        some calls to cond_resched().
@@ -44,7 +44,7 @@ warnings:
        result in the ``rcu_.*kthread starved for`` console-log message,
        which will include additional debugging information.
 
--      A CPU-bound real-time task in a CONFIG_PREEMPT kernel, which might
+-      A CPU-bound real-time task in a CONFIG_PREEMPTION kernel, which might
        happen to preempt a low-priority task in the middle of an RCU
        read-side critical section.   This is especially damaging if
        that low-priority task is not permitted to run on any other CPU,
index fb3ff76..3b2b147 100644 (file)
@@ -684,7 +684,7 @@ Quick Quiz #1:
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 This section presents a "toy" RCU implementation that is based on
 "classic RCU".  It is also short on performance (but only for updates) and
-on features such as hotplug CPU and the ability to run in CONFIG_PREEMPT
+on features such as hotplug CPU and the ability to run in CONFIG_PREEMPTION
 kernels.  The definitions of rcu_dereference() and rcu_assign_pointer()
 are the same as those shown in the preceding section, so they are omitted.
 ::
@@ -740,7 +740,7 @@ Quick Quiz #2:
 Quick Quiz #3:
                If it is illegal to block in an RCU read-side
                critical section, what the heck do you do in
-               PREEMPT_RT, where normal spinlocks can block???
+               CONFIG_PREEMPT_RT, where normal spinlocks can block???
 
 :ref:`Answers to Quick Quiz <8_whatisRCU>`
 
@@ -1094,7 +1094,7 @@ Quick Quiz #2:
                overhead is **negative**.
 
 Answer:
-               Imagine a single-CPU system with a non-CONFIG_PREEMPT
+               Imagine a single-CPU system with a non-CONFIG_PREEMPTION
                kernel where a routing table is used by process-context
                code, but can be updated by irq-context code (for example,
                by an "ICMP REDIRECT" packet).  The usual way of handling
@@ -1121,10 +1121,10 @@ Answer:
 Quick Quiz #3:
                If it is illegal to block in an RCU read-side
                critical section, what the heck do you do in
-               PREEMPT_RT, where normal spinlocks can block???
+               CONFIG_PREEMPT_RT, where normal spinlocks can block???
 
 Answer:
-               Just as PREEMPT_RT permits preemption of spinlock
+               Just as CONFIG_PREEMPT_RT permits preemption of spinlock
                critical sections, it permits preemption of RCU
                read-side critical sections.  It also permits
                spinlocks blocking while in RCU read-side critical
index d006189..4ee4dca 100644 (file)
                        value, meaning that RCU_SOFTIRQ is used by default.
                        Specify rcutree.use_softirq=0 to use rcuc kthreads.
 
+                       But note that CONFIG_PREEMPT_RT=y kernels disable
+                       this kernel boot parameter, forcibly setting it
+                       to zero.
+
        rcutree.rcu_fanout_exact= [KNL]
                        Disable autobalancing of the rcu_node combining
                        tree.  This is used by rcutorture, and might
                        only normal grace-period primitives.  No effect
                        on CONFIG_TINY_RCU kernels.
 
+                       But note that CONFIG_PREEMPT_RT=y kernels enables
+                       this kernel boot parameter, forcibly setting
+                       it to the value one, that is, converting any
+                       post-boot attempt at an expedited RCU grace
+                       period to instead use normal non-expedited
+                       grace-period processing.
+
        rcupdate.rcu_task_ipi_delay= [KNL]
                        Set time in jiffies during which RCU tasks will
                        avoid sending IPIs, starting with the beginning
index a966239..a7830c5 100644 (file)
@@ -20,78 +20,64 @@ A mapping object is created during driver initialization using::
 mappable, while 'size' indicates how large a mapping region to
 enable. Both are in bytes.
 
-This _wc variant provides a mapping which may only be used
-with the io_mapping_map_atomic_wc or io_mapping_map_wc.
+This _wc variant provides a mapping which may only be used with
+io_mapping_map_local_wc() or io_mapping_map_wc().
 
-With this mapping object, individual pages can be mapped either atomically
-or not, depending on the necessary scheduling environment. Of course, atomic
-maps are more efficient::
+With this mapping object, individual pages can be mapped either temporarily
+or long term, depending on the requirements. Of course, temporary maps are
+more efficient.
 
-       void *io_mapping_map_atomic_wc(struct io_mapping *mapping,
-                                      unsigned long offset)
+       void *io_mapping_map_local_wc(struct io_mapping *mapping,
+                                     unsigned long offset)
 
-'offset' is the offset within the defined mapping region.
-Accessing addresses beyond the region specified in the
-creation function yields undefined results. Using an offset
-which is not page aligned yields an undefined result. The
-return value points to a single page in CPU address space.
+'offset' is the offset within the defined mapping region.  Accessing
+addresses beyond the region specified in the creation function yields
+undefined results. Using an offset which is not page aligned yields an
+undefined result. The return value points to a single page in CPU address
+space.
 
-This _wc variant returns a write-combining map to the
-page and may only be used with mappings created by
-io_mapping_create_wc
+This _wc variant returns a write-combining map to the page and may only be
+used with mappings created by io_mapping_create_wc()
 
-Note that the task may not sleep while holding this page
-mapped.
+Temporary mappings are only valid in the context of the caller. The mapping
+is not guaranteed to be globaly visible.
 
-::
+io_mapping_map_local_wc() has a side effect on X86 32bit as it disables
+migration to make the mapping code work. No caller can rely on this side
+effect.
 
-       void io_mapping_unmap_atomic(void *vaddr)
+Nested mappings need to be undone in reverse order because the mapping
+code uses a stack for keeping track of them::
 
-'vaddr' must be the value returned by the last
-io_mapping_map_atomic_wc call. This unmaps the specified
-page and allows the task to sleep once again.
+ addr1 = io_mapping_map_local_wc(map1, offset1);
+ addr2 = io_mapping_map_local_wc(map2, offset2);
+ ...
+ io_mapping_unmap_local(addr2);
+ io_mapping_unmap_local(addr1);
 
-If you need to sleep while holding the lock, you can use the non-atomic
-variant, although they may be significantly slower.
+The mappings are released with::
 
-::
+       void io_mapping_unmap_local(void *vaddr)
+
+'vaddr' must be the value returned by the last io_mapping_map_local_wc()
+call. This unmaps the specified mapping and undoes eventual side effects of
+the mapping function.
+
+If you need to sleep while holding a mapping, you can use the regular
+variant, although this may be significantly slower::
 
        void *io_mapping_map_wc(struct io_mapping *mapping,
                                unsigned long offset)
 
-This works like io_mapping_map_atomic_wc except it allows
-the task to sleep while holding the page mapped.
+This works like io_mapping_map_local_wc() except it has no side effects and
+the pointer is globaly visible.
 
-
-::
+The mappings are released with::
 
        void io_mapping_unmap(void *vaddr)
 
-This works like io_mapping_unmap_atomic, except it is used
-for pages mapped with io_mapping_map_wc.
+Use for pages mapped with io_mapping_map_wc().
 
 At driver close time, the io_mapping object must be freed::
 
        void io_mapping_free(struct io_mapping *mapping)
-
-Current Implementation
-======================
-
-The initial implementation of these functions uses existing mapping
-mechanisms and so provides only an abstraction layer and no new
-functionality.
-
-On 64-bit processors, io_mapping_create_wc calls ioremap_wc for the whole
-range, creating a permanent kernel-visible mapping to the resource. The
-map_atomic and map functions add the requested offset to the base of the
-virtual address returned by ioremap_wc.
-
-On 32-bit processors with HIGHMEM defined, io_mapping_map_atomic_wc uses
-kmap_atomic_pfn to map the specified page in an atomic fashion;
-kmap_atomic_pfn isn't really supposed to be used with device pages, but it
-provides an efficient mapping for this usage.
-
-On 32-bit processors without HIGHMEM defined, io_mapping_map_atomic_wc and
-io_mapping_map_wc both use ioremap_wc, a terribly inefficient function which
-performs an IPI to inform all processors about the new mapping. This results
-in a significant performance penalty.
index 632d60e..c471340 100644 (file)
@@ -37,6 +37,7 @@ config OPROFILE
        tristate "OProfile system profiling"
        depends on PROFILING
        depends on HAVE_OPROFILE
+       depends on !PREEMPT_RT
        select RING_BUFFER
        select RING_BUFFER_ALLOW_SWAP
        help
@@ -643,6 +644,12 @@ config HAVE_TIF_NOHZ
 config HAVE_VIRT_CPU_ACCOUNTING
        bool
 
+config HAVE_VIRT_CPU_ACCOUNTING_IDLE
+       bool
+       help
+         Architecture has its own way to account idle CPU time and therefore
+         doesn't implement vtime_account_idle().
+
 config ARCH_HAS_SCALED_CPUTIME
        bool
 
@@ -657,7 +664,6 @@ config HAVE_VIRT_CPU_ACCOUNTING_GEN
          some 32-bit arches may require multiple accesses, so proper
          locking is needed to protect against concurrent accesses.
 
-
 config HAVE_IRQ_TIME_ACCOUNTING
        bool
        help
diff --git a/arch/alpha/include/asm/kmap_types.h b/arch/alpha/include/asm/kmap_types.h
deleted file mode 100644 (file)
index 651714b..0000000
+++ /dev/null
@@ -1,15 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_KMAP_TYPES_H
-#define _ASM_KMAP_TYPES_H
-
-/* Dummy header just to define km_type. */
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-#define  __WITH_KM_FENCE
-#endif
-
-#include <asm-generic/kmap_types.h>
-
-#undef __WITH_KM_FENCE
-
-#endif
index 1d5716b..6883bc9 100644 (file)
@@ -2,10 +2,6 @@
 #ifndef _ALPHA_SPINLOCK_TYPES_H
 #define _ALPHA_SPINLOCK_TYPES_H
 
-#ifndef __LINUX_SPINLOCK_TYPES_H
-# error "please don't include this file directly"
-#endif
-
 typedef struct {
        volatile unsigned int lock;
 } arch_spinlock_t;
index 0a89cc9..d880400 100644 (file)
@@ -507,6 +507,7 @@ config LINUX_RAM_BASE
 config HIGHMEM
        bool "High Memory Support"
        select ARCH_DISCONTIGMEM_ENABLE
+       select KMAP_LOCAL
        help
          With ARC 2G:2G address split, only upper 2G is directly addressable by
          kernel. Enable this to potentially allow access to rest of 2G and PAE
index 6e5eafb..a6b8e2c 100644 (file)
@@ -9,17 +9,29 @@
 #ifdef CONFIG_HIGHMEM
 
 #include <uapi/asm/page.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
+
+#define FIXMAP_SIZE            PGDIR_SIZE
+#define PKMAP_SIZE             PGDIR_SIZE
 
 /* start after vmalloc area */
 #define FIXMAP_BASE            (PAGE_OFFSET - FIXMAP_SIZE - PKMAP_SIZE)
-#define FIXMAP_SIZE            PGDIR_SIZE      /* only 1 PGD worth */
-#define KM_TYPE_NR             ((FIXMAP_SIZE >> PAGE_SHIFT)/NR_CPUS)
-#define FIXMAP_ADDR(nr)                (FIXMAP_BASE + ((nr) << PAGE_SHIFT))
+
+#define FIX_KMAP_SLOTS         (KM_MAX_IDX * NR_CPUS)
+#define FIX_KMAP_BEGIN         (0UL)
+#define FIX_KMAP_END           ((FIX_KMAP_BEGIN + FIX_KMAP_SLOTS) - 1)
+
+#define FIXADDR_TOP            (FIXMAP_BASE + (FIX_KMAP_END << PAGE_SHIFT))
+
+/*
+ * This should be converted to the asm-generic version, but of course this
+ * is needlessly different from all other architectures. Sigh - tglx
+ */
+#define __fix_to_virt(x)       (FIXADDR_TOP - ((x) << PAGE_SHIFT))
+#define __virt_to_fix(x)       (((FIXADDR_TOP - ((x) & PAGE_MASK))) >> PAGE_SHIFT)
 
 /* start after fixmap area */
 #define PKMAP_BASE             (FIXMAP_BASE + FIXMAP_SIZE)
-#define PKMAP_SIZE             PGDIR_SIZE
 #define LAST_PKMAP             (PKMAP_SIZE >> PAGE_SHIFT)
 #define LAST_PKMAP_MASK                (LAST_PKMAP - 1)
 #define PKMAP_ADDR(nr)         (PKMAP_BASE + ((nr) << PAGE_SHIFT))
 
 extern void kmap_init(void);
 
+#define arch_kmap_local_post_unmap(vaddr)                      \
+       local_flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE)
+
 static inline void flush_cache_kmaps(void)
 {
        flush_cache_all();
 }
-
 #endif
 
 #endif
diff --git a/arch/arc/include/asm/kmap_types.h b/arch/arc/include/asm/kmap_types.h
deleted file mode 100644 (file)
index fecf785..0000000
+++ /dev/null
@@ -1,14 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
-/*
- * Copyright (C) 2015 Synopsys, Inc. (www.synopsys.com)
- */
-
-#ifndef _ASM_KMAP_TYPES_H
-#define _ASM_KMAP_TYPES_H
-
-/*
- * We primarily need to define KM_TYPE_NR here but that in turn
- * is a function of PGDIR_SIZE etc.
- * To avoid circular deps issue, put everything in asm/highmem.h
- */
-#endif
index 1b9f473..c79912a 100644 (file)
@@ -36,9 +36,8 @@
  *   This means each only has 1 PGDIR_SIZE worth of kvaddr mappings, which means
  *   2M of kvaddr space for typical config (8K page and 11:8:13 traversal split)
  *
- * - fixmap anyhow needs a limited number of mappings. So 2M kvaddr == 256 PTE
- *   slots across NR_CPUS would be more than sufficient (generic code defines
- *   KM_TYPE_NR as 20).
+ * - The fixed KMAP slots for kmap_local/atomic() require KM_MAX_IDX slots per
+ *   CPU. So the number of CPUs sharing a single PTE page is limited.
  *
  * - pkmap being preemptible, in theory could do with more than 256 concurrent
  *   mappings. However, generic pkmap code: map_new_virtual(), doesn't traverse
  */
 
 extern pte_t * pkmap_page_table;
-static pte_t * fixmap_page_table;
-
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
-       int idx, cpu_idx;
-       unsigned long vaddr;
-
-       cpu_idx = kmap_atomic_idx_push();
-       idx = cpu_idx + KM_TYPE_NR * smp_processor_id();
-       vaddr = FIXMAP_ADDR(idx);
-
-       set_pte_at(&init_mm, vaddr, fixmap_page_table + idx,
-                  mk_pte(page, prot));
-
-       return (void *)vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kv)
-{
-       unsigned long kvaddr = (unsigned long)kv;
-
-       if (kvaddr >= FIXMAP_BASE && kvaddr < (FIXMAP_BASE + FIXMAP_SIZE)) {
-
-               /*
-                * Because preemption is disabled, this vaddr can be associated
-                * with the current allocated index.
-                * But in case of multiple live kmap_atomic(), it still relies on
-                * callers to unmap in right order.
-                */
-               int cpu_idx = kmap_atomic_idx();
-               int idx = cpu_idx + KM_TYPE_NR * smp_processor_id();
-
-               WARN_ON(kvaddr != FIXMAP_ADDR(idx));
-
-               pte_clear(&init_mm, kvaddr, fixmap_page_table + idx);
-               local_flush_tlb_kernel_range(kvaddr, kvaddr + PAGE_SIZE);
-
-               kmap_atomic_idx_pop();
-       }
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
 
 static noinline pte_t * __init alloc_kmap_pgtable(unsigned long kvaddr)
 {
@@ -108,10 +65,9 @@ void __init kmap_init(void)
 {
        /* Due to recursive include hell, we can't do this in processor.h */
        BUILD_BUG_ON(PAGE_OFFSET < (VMALLOC_END + FIXMAP_SIZE + PKMAP_SIZE));
+       BUILD_BUG_ON(LAST_PKMAP > PTRS_PER_PTE);
+       BUILD_BUG_ON(FIX_KMAP_SLOTS > PTRS_PER_PTE);
 
-       BUILD_BUG_ON(KM_TYPE_NR > PTRS_PER_PTE);
        pkmap_page_table = alloc_kmap_pgtable(PKMAP_BASE);
-
-       BUILD_BUG_ON(LAST_PKMAP > PTRS_PER_PTE);
-       fixmap_page_table = alloc_kmap_pgtable(FIXMAP_BASE);
+       alloc_kmap_pgtable(FIXMAP_BASE);
 }
index c349343..a87c79a 100644 (file)
@@ -31,6 +31,7 @@ config ARM
        select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
        select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT if CPU_V7
        select ARCH_SUPPORTS_ATOMIC_RMW
+       select ARCH_SUPPORTS_RT if HAVE_POSIX_CPU_TIMERS_TASK_WORK
        select ARCH_USE_BUILTIN_BSWAP
        select ARCH_USE_CMPXCHG_LOCKREF
        select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
@@ -66,7 +67,7 @@ config ARM
        select HARDIRQS_SW_RESEND
        select HAVE_ARCH_AUDITSYSCALL if AEABI && !OABI_COMPAT
        select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
-       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
        select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
        select HAVE_ARCH_MMAP_RND_BITS if MMU
        select HAVE_ARCH_SECCOMP
@@ -106,6 +107,7 @@ config ARM
        select HAVE_PERF_EVENTS
        select HAVE_PERF_REGS
        select HAVE_PERF_USER_STACK_DUMP
+       select HAVE_PREEMPT_LAZY
        select MMU_GATHER_RCU_TABLE_FREE if SMP && ARM_LPAE
        select HAVE_REGS_AND_STACK_ACCESS_API
        select HAVE_RSEQ
@@ -121,6 +123,7 @@ config ARM
        select OLD_SIGSUSPEND3
        select PCI_SYSCALL if PCI
        select PERF_USE_VMALLOC
+       select HAVE_POSIX_CPU_TIMERS_TASK_WORK if !KVM
        select RTC_LIB
        select SET_FS
        select SYS_SUPPORTS_APM_EMULATION
@@ -1500,6 +1503,7 @@ config HAVE_ARCH_PFN_VALID
 config HIGHMEM
        bool "High Memory Support"
        depends on MMU
+       select KMAP_LOCAL
        help
          The address space of ARM processors is only 4 Gigabytes large
          and it has to accommodate user address space, kernel address
index 9575b40..707068f 100644 (file)
@@ -7,14 +7,14 @@
 #define FIXADDR_TOP            (FIXADDR_END - PAGE_SIZE)
 
 #include <linux/pgtable.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 
 enum fixed_addresses {
        FIX_EARLYCON_MEM_BASE,
        __end_of_permanent_fixed_addresses,
 
        FIX_KMAP_BEGIN = __end_of_permanent_fixed_addresses,
-       FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS) - 1,
+       FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
 
        /* Support writing RO kernel text via kprobes, jump labels, etc. */
        FIX_TEXT_POKE0,
index b95848e..706efaf 100644 (file)
@@ -2,16 +2,11 @@
 #ifndef __ASM_HARDIRQ_H
 #define __ASM_HARDIRQ_H
 
-#include <linux/cache.h>
-#include <linux/threads.h>
 #include <asm/irq.h>
 
-typedef struct {
-       unsigned int __softirq_pending;
-} ____cacheline_aligned irq_cpustat_t;
-
-#include <linux/irq_cpustat.h> /* Standard mappings for irq_cpustat_t above */
-
 #define __ARCH_IRQ_EXIT_IRQS_DISABLED  1
+#define ack_bad_irq ack_bad_irq
+
+#include <asm-generic/hardirq.h>
 
 #endif /* __ASM_HARDIRQ_H */
index 31811be..b22dffa 100644 (file)
@@ -2,7 +2,8 @@
 #ifndef _ASM_HIGHMEM_H
 #define _ASM_HIGHMEM_H
 
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
+#include <asm/fixmap.h>
 
 #define PKMAP_BASE             (PAGE_OFFSET - PMD_SIZE)
 #define LAST_PKMAP             PTRS_PER_PTE
@@ -46,19 +47,32 @@ extern pte_t *pkmap_page_table;
 
 #ifdef ARCH_NEEDS_KMAP_HIGH_GET
 extern void *kmap_high_get(struct page *page);
-#else
+
+static inline void *arch_kmap_local_high_get(struct page *page)
+{
+       if (IS_ENABLED(CONFIG_DEBUG_HIGHMEM) && !cache_is_vivt())
+               return NULL;
+       return kmap_high_get(page);
+}
+#define arch_kmap_local_high_get arch_kmap_local_high_get
+
+#else /* ARCH_NEEDS_KMAP_HIGH_GET */
 static inline void *kmap_high_get(struct page *page)
 {
        return NULL;
 }
-#endif
+#endif /* !ARCH_NEEDS_KMAP_HIGH_GET */
 
-/*
- * The following functions are already defined by <linux/highmem.h>
- * when CONFIG_HIGHMEM is not set.
- */
-#ifdef CONFIG_HIGHMEM
-extern void *kmap_atomic_pfn(unsigned long pfn);
-#endif
+#define arch_kmap_local_post_map(vaddr, pteval)                                \
+       local_flush_tlb_kernel_page(vaddr)
+
+#define arch_kmap_local_pre_unmap(vaddr)                               \
+do {                                                                   \
+       if (cache_is_vivt())                                            \
+               __cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE);     \
+} while (0)
+
+#define arch_kmap_local_post_unmap(vaddr)                              \
+       local_flush_tlb_kernel_page(vaddr)
 
 #endif
index 46d4114..1cbcc46 100644 (file)
@@ -31,6 +31,8 @@ void handle_IRQ(unsigned int, struct pt_regs *);
 void init_IRQ(void);
 
 #ifdef CONFIG_SMP
+#include <linux/cpumask.h>
+
 extern void arch_trigger_cpumask_backtrace(const cpumask_t *mask,
                                           bool exclude_self);
 #define arch_trigger_cpumask_backtrace arch_trigger_cpumask_backtrace
diff --git a/arch/arm/include/asm/kmap_types.h b/arch/arm/include/asm/kmap_types.h
deleted file mode 100644 (file)
index 5590940..0000000
+++ /dev/null
@@ -1,10 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __ARM_KMAP_TYPES_H
-#define __ARM_KMAP_TYPES_H
-
-/*
- * This is the "bare minimum".  AIO seems to require this.
- */
-#define KM_TYPE_NR 16
-
-#endif
index 5976958..a37c080 100644 (file)
@@ -2,10 +2,6 @@
 #ifndef __ASM_SPINLOCK_TYPES_H
 #define __ASM_SPINLOCK_TYPES_H
 
-#ifndef __LINUX_SPINLOCK_TYPES_H
-# error "please don't include this file directly"
-#endif
-
 #define TICKET_SHIFT   16
 
 typedef struct {
index 536b6b9..875aaf9 100644 (file)
@@ -46,6 +46,7 @@ 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 */
@@ -134,7 +135,8 @@ 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_NEED_RESCHED_LAZY  7
+#define TIF_SECCOMP            8       /* seccomp syscall filtering active */
 
 #define TIF_USING_IWMMXT       17
 #define TIF_MEMDIE             18      /* is terminating due to OOM killer */
@@ -143,6 +145,7 @@ 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)
@@ -158,7 +161,8 @@ 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 70993af..024c65c 100644 (file)
@@ -43,6 +43,7 @@ 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 63fbcdc..4a9594f 100644 (file)
@@ -206,11 +206,18 @@ __irq_svc:
 
 #ifdef CONFIG_PREEMPTION
        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
@@ -225,8 +232,14 @@ 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 271cb8a..fd039b1 100644 (file)
@@ -53,7 +53,9 @@ __ret_fast_syscall:
        cmp     r2, #TASK_SIZE
        blne    addr_limit_check_failed
        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
 
 
@@ -90,8 +92,11 @@ __ret_fast_syscall:
        cmp     r2, #TASK_SIZE
        blne    addr_limit_check_failed
        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 2f81d3a..6e69f7b 100644 (file)
@@ -649,7 +649,8 @@ 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 8aa7fa9..3693706 100644 (file)
@@ -671,9 +671,7 @@ static void do_handle_IPI(int ipinr)
                break;
 
        case IPI_CPU_BACKTRACE:
-               printk_nmi_enter();
                nmi_cpu_backtrace(get_irq_regs());
-               printk_nmi_exit();
                break;
 
        default:
index 7cb1699..c4ce477 100644 (file)
@@ -19,7 +19,6 @@ obj-$(CONFIG_MODULES)         += proc-syms.o
 obj-$(CONFIG_DEBUG_VIRTUAL)    += physaddr.o
 
 obj-$(CONFIG_ALIGNMENT_TRAP)   += alignment.o
-obj-$(CONFIG_HIGHMEM)          += highmem.o
 obj-$(CONFIG_HUGETLB_PAGE)     += hugetlbpage.o
 obj-$(CONFIG_ARM_PV_FIXUP)     += pv-fixup-asm.o
 
index 5c1b7a7..8732876 100644 (file)
@@ -49,9 +49,9 @@ static inline unsigned long l2_get_va(unsigned long paddr)
         * we simply install a virtual mapping for it only for the
         * TLB lookup to occur, hence no need to flush the untouched
         * memory mapping afterwards (note: a cache flush may happen
-        * in some circumstances depending on the path taken in kunmap_atomic).
+        * in some circumstances depending on the path taken in kunmap_local).
         */
-       void *vaddr = kmap_atomic_pfn(paddr >> PAGE_SHIFT);
+       void *vaddr = kmap_local_pfn(paddr >> PAGE_SHIFT);
        return (unsigned long)vaddr + (paddr & ~PAGE_MASK);
 #else
        return __phys_to_virt(paddr);
@@ -61,7 +61,7 @@ static inline unsigned long l2_get_va(unsigned long paddr)
 static inline void l2_put_va(unsigned long vaddr)
 {
 #ifdef CONFIG_HIGHMEM
-       kunmap_atomic((void *)vaddr);
+       kunmap_local((void *)vaddr);
 #endif
 }
 
index d20d7af..0e0a3ab 100644 (file)
@@ -59,7 +59,7 @@ static inline void l2_unmap_va(unsigned long va)
 {
 #ifdef CONFIG_HIGHMEM
        if (va != -1)
-               kunmap_atomic((void *)va);
+               kunmap_local((void *)va);
 #endif
 }
 
@@ -75,7 +75,7 @@ static inline unsigned long l2_map_va(unsigned long pa, unsigned long prev_va)
                 * in place for it.
                 */
                l2_unmap_va(prev_va);
-               va = (unsigned long)kmap_atomic_pfn(pa >> PAGE_SHIFT);
+               va = (unsigned long)kmap_local_pfn(pa >> PAGE_SHIFT);
        }
        return va + (pa_offset >> (32 - PAGE_SHIFT));
 #else
index efa4020..59487ee 100644 (file)
@@ -400,6 +400,9 @@ 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;
 
@@ -470,6 +473,9 @@ 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;
 }
diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c
deleted file mode 100644 (file)
index 187fab2..0000000
+++ /dev/null
@@ -1,121 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * arch/arm/mm/highmem.c -- ARM highmem support
- *
- * Author:     Nicolas Pitre
- * Created:    september 8, 2008
- * Copyright:  Marvell Semiconductors Inc.
- */
-
-#include <linux/module.h>
-#include <linux/highmem.h>
-#include <linux/interrupt.h>
-#include <asm/fixmap.h>
-#include <asm/cacheflush.h>
-#include <asm/tlbflush.h>
-#include "mm.h"
-
-static inline void set_fixmap_pte(int idx, pte_t pte)
-{
-       unsigned long vaddr = __fix_to_virt(idx);
-       pte_t *ptep = virt_to_kpte(vaddr);
-
-       set_pte_ext(ptep, pte, 0);
-       local_flush_tlb_kernel_page(vaddr);
-}
-
-static inline pte_t get_fixmap_pte(unsigned long vaddr)
-{
-       pte_t *ptep = virt_to_kpte(vaddr);
-
-       return *ptep;
-}
-
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
-       unsigned int idx;
-       unsigned long vaddr;
-       void *kmap;
-       int type;
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-       /*
-        * There is no cache coherency issue when non VIVT, so force the
-        * dedicated kmap usage for better debugging purposes in that case.
-        */
-       if (!cache_is_vivt())
-               kmap = NULL;
-       else
-#endif
-               kmap = kmap_high_get(page);
-       if (kmap)
-               return kmap;
-
-       type = kmap_atomic_idx_push();
-
-       idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
-       vaddr = __fix_to_virt(idx);
-#ifdef CONFIG_DEBUG_HIGHMEM
-       /*
-        * With debugging enabled, kunmap_atomic forces that entry to 0.
-        * Make sure it was indeed properly unmapped.
-        */
-       BUG_ON(!pte_none(get_fixmap_pte(vaddr)));
-#endif
-       /*
-        * When debugging is off, kunmap_atomic leaves the previous mapping
-        * in place, so the contained TLB flush ensures the TLB is updated
-        * with the new mapping.
-        */
-       set_fixmap_pte(idx, mk_pte(page, prot));
-
-       return (void *)vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
-       unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-       int idx, type;
-
-       if (kvaddr >= (void *)FIXADDR_START) {
-               type = kmap_atomic_idx();
-               idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
-
-               if (cache_is_vivt())
-                       __cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE);
-#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
-               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)]));
-       }
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
-
-void *kmap_atomic_pfn(unsigned long pfn)
-{
-       unsigned long vaddr;
-       int idx, type;
-       struct page *page = pfn_to_page(pfn);
-
-       preempt_disable();
-       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();
-       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));
-
-       return (void *)vaddr;
-}
index 3da71fe..3ba7b56 100644 (file)
@@ -76,6 +76,7 @@ config ARM64
        select ARCH_SUPPORTS_ATOMIC_RMW
        select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && (GCC_VERSION >= 50000 || CC_IS_CLANG)
        select ARCH_SUPPORTS_NUMA_BALANCING
+       select ARCH_SUPPORTS_RT if HAVE_POSIX_CPU_TIMERS_TASK_WORK
        select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
        select ARCH_WANT_DEFAULT_BPF_JIT
        select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
@@ -173,6 +174,7 @@ 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_FUNCTION_ARG_ACCESS_API
        select HAVE_FUTEX_CMPXCHG if FUTEX
@@ -194,6 +196,7 @@ config ARM64
        select PCI_DOMAINS_GENERIC if PCI
        select PCI_ECAM if (ACPI && PCI)
        select PCI_SYSCALL if PCI
+       select HAVE_POSIX_CPU_TIMERS_TASK_WORK if !KVM
        select POWER_RESET
        select POWER_SUPPLY
        select SET_FS
index 5ffa4ba..cbfa7b6 100644 (file)
 #include <asm/kvm_arm.h>
 #include <asm/sysreg.h>
 
-typedef struct {
-       unsigned int __softirq_pending;
-} ____cacheline_aligned irq_cpustat_t;
-
-#include <linux/irq_cpustat.h> /* Standard mappings for irq_cpustat_t above */
+#define ack_bad_irq ack_bad_irq
+#include <asm-generic/hardirq.h>
 
 #define __ARCH_IRQ_EXIT_IRQS_DISABLED  1
 
index e83f098..7a5770d 100644 (file)
@@ -70,17 +70,43 @@ static inline bool __preempt_count_dec_and_test(void)
         * interrupt occurring between the non-atomic READ_ONCE/WRITE_ONCE
         * pair.
         */
-       return !pc || !READ_ONCE(ti->preempt_count);
+       if (!pc || !READ_ONCE(ti->preempt_count))
+               return true;
+#ifdef CONFIG_PREEMPT_LAZY
+       if ((pc & ~PREEMPT_NEED_RESCHED))
+               return false;
+       if (current_thread_info()->preempt_lazy_count)
+               return false;
+       return test_thread_flag(TIF_NEED_RESCHED_LAZY);
+#else
+       return false;
+#endif
 }
 
 static inline bool should_resched(int preempt_offset)
 {
+#ifdef CONFIG_PREEMPT_LAZY
+       u64 pc = READ_ONCE(current_thread_info()->preempt_count);
+       if (pc == preempt_offset)
+               return true;
+
+       if ((pc & ~PREEMPT_NEED_RESCHED) != preempt_offset)
+               return false;
+
+       if (current_thread_info()->preempt_lazy_count)
+               return false;
+       return test_thread_flag(TIF_NEED_RESCHED_LAZY);
+#else
        u64 pc = READ_ONCE(current_thread_info()->preempt_count);
        return pc == preempt_offset;
+#endif
 }
 
 #ifdef CONFIG_PREEMPTION
 void preempt_schedule(void);
+#ifdef CONFIG_PREEMPT_RT
+void preempt_schedule_lock(void);
+#endif
 #define __preempt_schedule() preempt_schedule()
 void preempt_schedule_notrace(void);
 #define __preempt_schedule_notrace() preempt_schedule_notrace()
index 18782f0..6672b05 100644 (file)
@@ -5,10 +5,6 @@
 #ifndef __ASM_SPINLOCK_TYPES_H
 #define __ASM_SPINLOCK_TYPES_H
 
-#if !defined(__LINUX_SPINLOCK_TYPES_H) && !defined(__ASM_SPINLOCK_H)
-# error "please don't include this file directly"
-#endif
-
 #include <asm-generic/qspinlock_types.h>
 #include <asm-generic/qrwlock_types.h>
 
index 1fbab85..148b53d 100644 (file)
@@ -29,6 +29,7 @@ struct thread_info {
 #ifdef CONFIG_ARM64_SW_TTBR0_PAN
        u64                     ttbr0;          /* saved TTBR0_EL1 */
 #endif
+       int                     preempt_lazy_count;     /* 0 => preemptable, <0 => bug */
        union {
                u64             preempt_count;  /* 0 => preemptible, <0 => bug */
                struct {
@@ -68,6 +69,7 @@ void arch_release_task_struct(struct task_struct *tsk);
 #define TIF_UPROBE             4       /* uprobe breakpoint or singlestep */
 #define TIF_FSCHECK            5       /* Check FS is USER_DS on return */
 #define TIF_MTE_ASYNC_FAULT    6       /* MTE Asynchronous Tag Check Fault */
+#define TIF_NEED_RESCHED_LAZY  7
 #define TIF_SYSCALL_TRACE      8       /* syscall trace active */
 #define TIF_SYSCALL_AUDIT      9       /* syscall auditing */
 #define TIF_SYSCALL_TRACEPOINT 10      /* syscall tracepoint for ftrace */
@@ -98,11 +100,14 @@ void arch_release_task_struct(struct task_struct *tsk);
 #define _TIF_32BIT             (1 << TIF_32BIT)
 #define _TIF_SVE               (1 << TIF_SVE)
 #define _TIF_MTE_ASYNC_FAULT   (1 << TIF_MTE_ASYNC_FAULT)
+#define _TIF_NEED_RESCHED_LAZY (1 << TIF_NEED_RESCHED_LAZY)
 
 #define _TIF_WORK_MASK         (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \
                                 _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE | \
-                                _TIF_UPROBE | _TIF_FSCHECK | _TIF_MTE_ASYNC_FAULT)
+                                _TIF_UPROBE | _TIF_FSCHECK | _TIF_MTE_ASYNC_FAULT | \
+                                _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 | \
                                 _TIF_SYSCALL_EMU)
index 7d32fc9..b2f29bd 100644 (file)
@@ -30,6 +30,7 @@ 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 fe83d6d..cd2fc55 100644 (file)
@@ -515,9 +515,18 @@ alternative_if ARM64_HAS_IRQ_PRIO_MASKING
        mrs     x0, daif
        orr     x24, x24, x0
 alternative_else_nop_endif
-       cbnz    x24, 1f                         // preempt count != 0 || NMI return path
-       bl      arm64_preempt_schedule_irq      // irq en/disable is done inside
+
+       cbz     x24, 1f                                 // (need_resched + count) == 0
+       cbnz    w24, 2f                                 // count != 0
+
+       ldr     w24, [tsk, #TSK_TI_PREEMPT_LAZY]        // get preempt lazy count
+       cbnz    w24, 2f                                 // preempt lazy count != 0
+
+       ldr     x0, [tsk, #TSK_TI_FLAGS]                // get flags
+       tbz     x0, #TIF_NEED_RESCHED_LAZY, 2f          // needs rescheduling?
 1:
+       bl      arm64_preempt_schedule_irq              // irq en/disable is done inside
+2:
 #endif
 
        mov     x0, sp
index a9bbfb8..aa63177 100644 (file)
@@ -226,6 +226,16 @@ static void sve_free(struct task_struct *task)
        __sve_free(task);
 }
 
+static void *sve_free_atomic(struct task_struct *task)
+{
+       void *sve_state = task->thread.sve_state;
+
+       WARN_ON(test_tsk_thread_flag(task, TIF_SVE));
+
+       task->thread.sve_state = NULL;
+       return sve_state;
+}
+
 /*
  * TIF_SVE controls whether a task can use SVE without trapping while
  * in userspace, and also the way a task's FPSIMD/SVE state is stored
@@ -1022,6 +1032,7 @@ void fpsimd_thread_switch(struct task_struct *next)
 void fpsimd_flush_thread(void)
 {
        int vl, supported_vl;
+       void *mem = NULL;
 
        if (!system_supports_fpsimd())
                return;
@@ -1034,7 +1045,7 @@ void fpsimd_flush_thread(void)
 
        if (system_supports_sve()) {
                clear_thread_flag(TIF_SVE);
-               sve_free(current);
+               mem = sve_free_atomic(current);
 
                /*
                 * Reset the task vector length as required.
@@ -1068,6 +1079,7 @@ void fpsimd_flush_thread(void)
        }
 
        put_cpu_fpsimd_context();
+       kfree(mem);
 }
 
 /*
index e620053..fe94a3e 100644 (file)
@@ -919,7 +919,7 @@ asmlinkage void do_notify_resume(struct pt_regs *regs,
                /* Check valid user FS if needed */
                addr_limit_user_check();
 
-               if (thread_flags & _TIF_NEED_RESCHED) {
+               if (thread_flags & _TIF_NEED_RESCHED_MASK) {
                        /* Unmask Debug and SError for the next task */
                        local_daif_restore(DAIF_PROCCTX_NOIRQ);
 
index 5bc978b..f262bb6 100644 (file)
@@ -708,7 +708,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
                 * involves poking the GIC, which must be done in a
                 * non-preemptible context.
                 */
-               preempt_disable();
+               migrate_disable();
 
                kvm_pmu_flush_hwstate(vcpu);
 
@@ -757,7 +757,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
                                kvm_timer_sync_user(vcpu);
                        kvm_vgic_sync_hwstate(vcpu);
                        local_irq_enable();
-                       preempt_enable();
+                       migrate_enable();
                        continue;
                }
 
@@ -829,7 +829,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
                /* Exit types that need handling before we can be preempted */
                handle_exit_early(vcpu, ret);
 
-               preempt_enable();
+               migrate_enable();
 
                /*
                 * The ARMv8 architecture doesn't give the hypervisor
index 7bf0a61..c9f2533 100644 (file)
@@ -286,6 +286,7 @@ config NR_CPUS
 config HIGHMEM
        bool "High Memory Support"
        depends on !CPU_CK610
+       select KMAP_LOCAL
        default y
 
 config FORCE_MAX_ZONEORDER
index 81f9477..4b589cc 100644 (file)
@@ -8,7 +8,7 @@
 #include <asm/memory.h>
 #ifdef CONFIG_HIGHMEM
 #include <linux/threads.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 #endif
 
 enum fixed_addresses {
@@ -17,7 +17,7 @@ enum fixed_addresses {
 #endif
 #ifdef CONFIG_HIGHMEM
        FIX_KMAP_BEGIN,
-       FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS) - 1,
+       FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
 #endif
        __end_of_fixed_addresses
 };
index 14645e3..1f4ed3f 100644 (file)
@@ -9,7 +9,7 @@
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/uaccess.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 #include <asm/cache.h>
 
 /* undef for production */
@@ -32,10 +32,12 @@ extern pte_t *pkmap_page_table;
 
 #define ARCH_HAS_KMAP_FLUSH_TLB
 extern void kmap_flush_tlb(unsigned long addr);
-extern void *kmap_atomic_pfn(unsigned long pfn);
 
 #define flush_cache_kmaps() do {} while (0)
 
+#define arch_kmap_local_post_map(vaddr, pteval)        kmap_flush_tlb(vaddr)
+#define arch_kmap_local_post_unmap(vaddr)      kmap_flush_tlb(vaddr)
+
 extern void kmap_init(void);
 
 #endif /* __KERNEL__ */
index 89c1080..4161df3 100644 (file)
@@ -9,8 +9,6 @@
 #include <asm/tlbflush.h>
 #include <asm/cacheflush.h>
 
-static pte_t *kmap_pte;
-
 unsigned long highstart_pfn, highend_pfn;
 
 void kmap_flush_tlb(unsigned long addr)
@@ -19,67 +17,7 @@ void kmap_flush_tlb(unsigned long addr)
 }
 EXPORT_SYMBOL(kmap_flush_tlb);
 
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
-       unsigned long vaddr;
-       int idx, type;
-
-       type = kmap_atomic_idx_push();
-       idx = type + KM_TYPE_NR*smp_processor_id();
-       vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-#ifdef CONFIG_DEBUG_HIGHMEM
-       BUG_ON(!pte_none(*(kmap_pte - idx)));
-#endif
-       set_pte(kmap_pte-idx, mk_pte(page, prot));
-       flush_tlb_one((unsigned long)vaddr);
-
-       return (void *)vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
-       unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-       int idx;
-
-       if (vaddr < FIXADDR_START)
-               return;
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-       idx = KM_TYPE_NR*smp_processor_id() + kmap_atomic_idx();
-
-       BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
-
-       pte_clear(&init_mm, vaddr, kmap_pte - idx);
-       flush_tlb_one(vaddr);
-#else
-       (void) idx; /* to kill a warning */
-#endif
-       kmap_atomic_idx_pop();
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
-
-/*
- * This is the same as kmap_atomic() but can map memory that doesn't
- * have a struct page associated with it.
- */
-void *kmap_atomic_pfn(unsigned long pfn)
-{
-       unsigned long vaddr;
-       int idx, type;
-
-       pagefault_disable();
-
-       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, PAGE_KERNEL));
-       flush_tlb_one(vaddr);
-
-       return (void *) vaddr;
-}
-
-static void __init kmap_pages_init(void)
+void __init kmap_init(void)
 {
        unsigned long vaddr;
        pgd_t *pgd;
@@ -96,14 +34,3 @@ static void __init kmap_pages_init(void)
        pte = pte_offset_kernel(pmd, vaddr);
        pkmap_page_table = pte;
 }
-
-void __init kmap_init(void)
-{
-       unsigned long vaddr;
-
-       kmap_pages_init();
-
-       vaddr = __fix_to_virt(FIX_KMAP_BEGIN);
-
-       kmap_pte = pte_offset_kernel((pmd_t *)pgd_offset_k(vaddr), vaddr);
-}
index 19d2334..de72fb2 100644 (file)
@@ -8,10 +8,6 @@
 #ifndef _ASM_SPINLOCK_TYPES_H
 #define _ASM_SPINLOCK_TYPES_H
 
-#ifndef __LINUX_SPINLOCK_TYPES_H
-# error "please don't include this file directly"
-#endif
-
 typedef struct {
        volatile unsigned int lock;
 } arch_spinlock_t;
diff --git a/arch/ia64/include/asm/kmap_types.h b/arch/ia64/include/asm/kmap_types.h
deleted file mode 100644 (file)
index 5c268cf..0000000
+++ /dev/null
@@ -1,13 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_IA64_KMAP_TYPES_H
-#define _ASM_IA64_KMAP_TYPES_H
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-#define  __WITH_KM_FENCE
-#endif
-
-#include <asm-generic/kmap_types.h>
-
-#undef __WITH_KM_FENCE
-
-#endif /* _ASM_IA64_KMAP_TYPES_H */
index 6e345fe..681408d 100644 (file)
@@ -2,10 +2,6 @@
 #ifndef _ASM_IA64_SPINLOCK_TYPES_H
 #define _ASM_IA64_SPINLOCK_TYPES_H
 
-#ifndef __LINUX_SPINLOCK_TYPES_H
-# error "please don't include this file directly"
-#endif
-
 typedef struct {
        volatile unsigned int lock;
 } arch_spinlock_t;
index 7abc5f3..733e0e3 100644 (file)
@@ -138,12 +138,8 @@ void vtime_account_kernel(struct task_struct *tsk)
        struct thread_info *ti = task_thread_info(tsk);
        __u64 stime = vtime_delta(tsk);
 
-       if ((tsk->flags & PF_VCPU) && !irq_count())
+       if (tsk->flags & PF_VCPU)
                ti->gtime += stime;
-       else if (hardirq_count())
-               ti->hardirq_time += stime;
-       else if (in_serving_softirq())
-               ti->softirq_time += stime;
        else
                ti->stime += stime;
 }
@@ -156,6 +152,20 @@ void vtime_account_idle(struct task_struct *tsk)
        ti->idle_time += vtime_delta(tsk);
 }
 
+void vtime_account_softirq(struct task_struct *tsk)
+{
+       struct thread_info *ti = task_thread_info(tsk);
+
+       ti->softirq_time += vtime_delta(tsk);
+}
+
+void vtime_account_hardirq(struct task_struct *tsk)
+{
+       struct thread_info *ti = task_thread_info(tsk);
+
+       ti->hardirq_time += vtime_delta(tsk);
+}
+
 #endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */
 
 static irqreturn_t
index 33925ff..7f6ca0a 100644 (file)
@@ -155,6 +155,7 @@ config XILINX_UNCACHED_SHADOW
 config HIGHMEM
        bool "High memory support"
        depends on MMU
+       select KMAP_LOCAL
        help
          The address space of Microblaze processors is only 4 Gigabytes large
          and it has to accommodate user address space, kernel address
index 0379ce5..e6e9288 100644 (file)
@@ -20,7 +20,7 @@
 #include <asm/page.h>
 #ifdef CONFIG_HIGHMEM
 #include <linux/threads.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 #endif
 
 #define FIXADDR_TOP    ((unsigned long)(-PAGE_SIZE))
@@ -47,7 +47,7 @@ enum fixed_addresses {
        FIX_HOLE,
 #ifdef CONFIG_HIGHMEM
        FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
-       FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * num_possible_cpus()) - 1,
+       FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * num_possible_cpus()) - 1,
 #endif
        __end_of_fixed_addresses
 };
index 284ca8f..4418633 100644 (file)
@@ -25,7 +25,6 @@
 #include <linux/uaccess.h>
 #include <asm/fixmap.h>
 
-extern pte_t *kmap_pte;
 extern pte_t *pkmap_page_table;
 
 /*
@@ -52,6 +51,11 @@ extern pte_t *pkmap_page_table;
 
 #define flush_cache_kmaps()    { flush_icache(); flush_dcache(); }
 
+#define arch_kmap_local_post_map(vaddr, pteval)        \
+       local_flush_tlb_page(NULL, vaddr);
+#define arch_kmap_local_post_unmap(vaddr)      \
+       local_flush_tlb_page(NULL, vaddr);
+
 #endif /* __KERNEL__ */
 
 #endif /* _ASM_HIGHMEM_H */
index 1b16875..8ced711 100644 (file)
@@ -6,4 +6,3 @@
 obj-y := consistent.o init.o
 
 obj-$(CONFIG_MMU) += pgtable.o mmu_context.o fault.o
-obj-$(CONFIG_HIGHMEM) += highmem.o
diff --git a/arch/microblaze/mm/highmem.c b/arch/microblaze/mm/highmem.c
deleted file mode 100644 (file)
index 92e0890..0000000
+++ /dev/null
@@ -1,78 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * highmem.c: virtual kernel memory mappings for high memory
- *
- * PowerPC version, stolen from the i386 version.
- *
- * Used in CONFIG_HIGHMEM systems for memory pages which
- * are not addressable by direct kernel virtual addresses.
- *
- * Copyright (C) 1999 Gerhard Wichert, Siemens AG
- *                   Gerhard.Wichert@pdb.siemens.de
- *
- *
- * Redesigned the x86 32-bit VM architecture to deal with
- * up to 16 Terrabyte physical memory. With current x86 CPUs
- * we now support up to 64 Gigabytes physical RAM.
- *
- * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com>
- *
- * Reworked for PowerPC by various contributors. Moved from
- * highmem.h by Benjamin Herrenschmidt (c) 2009 IBM Corp.
- */
-
-#include <linux/export.h>
-#include <linux/highmem.h>
-
-/*
- * The use of kmap_atomic/kunmap_atomic is discouraged - kmap/kunmap
- * gives a more generic (and caching) interface. But kmap_atomic can
- * be used in IRQ contexts, so in some (very limited) cases we need
- * it.
- */
-#include <asm/tlbflush.h>
-
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
-
-       unsigned long vaddr;
-       int idx, type;
-
-       type = kmap_atomic_idx_push();
-       idx = type + KM_TYPE_NR*smp_processor_id();
-       vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-#ifdef CONFIG_DEBUG_HIGHMEM
-       BUG_ON(!pte_none(*(kmap_pte-idx)));
-#endif
-       set_pte_at(&init_mm, vaddr, kmap_pte-idx, mk_pte(page, prot));
-       local_flush_tlb_page(NULL, vaddr);
-
-       return (void *) vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
-       unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-       int type;
-       unsigned int idx;
-
-       if (vaddr < __fix_to_virt(FIX_KMAP_END))
-               return;
-
-       type = kmap_atomic_idx();
-
-       idx = type + KM_TYPE_NR * smp_processor_id();
-#ifdef CONFIG_DEBUG_HIGHMEM
-       BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
-#endif
-       /*
-        * force other mappings to Oops if they'll try to access
-        * this pte without first remap it
-        */
-       pte_clear(&init_mm, vaddr, kmap_pte-idx);
-       local_flush_tlb_page(NULL, vaddr);
-
-       kmap_atomic_idx_pop();
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
index 45da639..1f4b5b3 100644 (file)
@@ -49,17 +49,11 @@ unsigned long lowmem_size;
 EXPORT_SYMBOL(min_low_pfn);
 EXPORT_SYMBOL(max_low_pfn);
 
-#ifdef CONFIG_HIGHMEM
-pte_t *kmap_pte;
-EXPORT_SYMBOL(kmap_pte);
-
 static void __init highmem_init(void)
 {
        pr_debug("%x\n", (u32)PKMAP_BASE);
        map_page(PKMAP_BASE, 0, 0);     /* XXX gross */
        pkmap_page_table = virt_to_kpte(PKMAP_BASE);
-
-       kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
 }
 
 static void highmem_setup(void)
index 3442bdd..30622f2 100644 (file)
@@ -2730,6 +2730,7 @@ config WAR_MIPS34K_MISSED_ITLB
 config HIGHMEM
        bool "High Memory Support"
        depends on 32BIT && CPU_SUPPORTS_HIGHMEM && SYS_SUPPORTS_HIGHMEM && !CPU_MIPS32_3_5_EVA
+       select KMAP_LOCAL
 
 config CPU_SUPPORTS_HIGHMEM
        bool
index 743535b..beea147 100644 (file)
@@ -17,7 +17,7 @@
 #include <spaces.h>
 #ifdef CONFIG_HIGHMEM
 #include <linux/threads.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 #endif
 
 /*
@@ -52,7 +52,7 @@ enum fixed_addresses {
 #ifdef CONFIG_HIGHMEM
        /* reserved pte's for temporary kernel mappings */
        FIX_KMAP_BEGIN = FIX_CMAP_END + 1,
-       FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
+       FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
 #endif
        __end_of_fixed_addresses
 };
index 9f021cf..1716181 100644 (file)
@@ -24,7 +24,7 @@
 #include <linux/interrupt.h>
 #include <linux/uaccess.h>
 #include <asm/cpu-features.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 
 /* declarations for highmem.c */
 extern unsigned long highstart_pfn, highend_pfn;
@@ -48,11 +48,11 @@ extern pte_t *pkmap_page_table;
 
 #define ARCH_HAS_KMAP_FLUSH_TLB
 extern void kmap_flush_tlb(unsigned long addr);
-extern void *kmap_atomic_pfn(unsigned long pfn);
 
 #define flush_cache_kmaps()    BUG_ON(cpu_has_dc_aliases)
 
-extern void kmap_init(void);
+#define arch_kmap_local_post_map(vaddr, pteval)        local_flush_tlb_one(vaddr)
+#define arch_kmap_local_post_unmap(vaddr)      local_flush_tlb_one(vaddr)
 
 #endif /* __KERNEL__ */
 
diff --git a/arch/mips/include/asm/kmap_types.h b/arch/mips/include/asm/kmap_types.h
deleted file mode 100644 (file)
index 16665dc..0000000
+++ /dev/null
@@ -1,13 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_KMAP_TYPES_H
-#define _ASM_KMAP_TYPES_H
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-#define         __WITH_KM_FENCE
-#endif
-
-#include <asm-generic/kmap_types.h>
-
-#undef __WITH_KM_FENCE
-
-#endif
index 01b2bd9..9aba83e 100644 (file)
@@ -5,8 +5,6 @@
 #include <linux/uaccess.h>
 #include <linux/slab.h>
 
-static void *kdump_buf_page;
-
 /**
  * copy_oldmem_page - copy one page from "oldmem"
  * @pfn: page frame number to be copied
@@ -17,51 +15,25 @@ static void *kdump_buf_page;
  * @userbuf: if set, @buf is in user address space, use copy_to_user(),
  *     otherwise @buf is in kernel address space, use memcpy().
  *
- * Copy a page from "oldmem". For this page, there is no pte mapped
+ * Copy a page from "oldmem". For this page, there might be no pte mapped
  * in the current kernel.
- *
- * Calling copy_to_user() in atomic context is not desirable. Hence first
- * copying the data to a pre-allocated kernel page and then copying to user
- * space in non-atomic context.
  */
-ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
-                        size_t csize, unsigned long offset, int userbuf)
+ssize_t copy_oldmem_page(unsigned long pfn, char *buf, size_t csize,
+                        unsigned long offset, int userbuf)
 {
        void  *vaddr;
 
        if (!csize)
                return 0;
 
-       vaddr = kmap_atomic_pfn(pfn);
+       vaddr = kmap_local_pfn(pfn);
 
        if (!userbuf) {
-               memcpy(buf, (vaddr + offset), csize);
-               kunmap_atomic(vaddr);
+               memcpy(buf, vaddr + offset, csize);
        } else {
-               if (!kdump_buf_page) {
-                       pr_warn("Kdump: Kdump buffer page not allocated\n");
-
-                       return -EFAULT;
-               }
-               copy_page(kdump_buf_page, vaddr);
-               kunmap_atomic(vaddr);
-               if (copy_to_user(buf, (kdump_buf_page + offset), csize))
-                       return -EFAULT;
+               if (copy_to_user(buf, vaddr + offset, csize))
+                       csize = -EFAULT;
        }
 
        return csize;
 }
-
-static int __init kdump_buf_page_init(void)
-{
-       int ret = 0;
-
-       kdump_buf_page = kmalloc(PAGE_SIZE, GFP_KERNEL);
-       if (!kdump_buf_page) {
-               pr_warn("Kdump: Failed to allocate kdump buffer page\n");
-               ret = -ENOMEM;
-       }
-
-       return ret;
-}
-arch_initcall(kdump_buf_page_init);
index 5fec7f4..57e2f08 100644 (file)
@@ -8,8 +8,6 @@
 #include <asm/fixmap.h>
 #include <asm/tlbflush.h>
 
-static pte_t *kmap_pte;
-
 unsigned long highstart_pfn, highend_pfn;
 
 void kmap_flush_tlb(unsigned long addr)
@@ -17,78 +15,3 @@ void kmap_flush_tlb(unsigned long addr)
        flush_tlb_one(addr);
 }
 EXPORT_SYMBOL(kmap_flush_tlb);
-
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
-       unsigned long vaddr;
-       int idx, type;
-
-       type = kmap_atomic_idx_push();
-       idx = type + KM_TYPE_NR*smp_processor_id();
-       vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-#ifdef CONFIG_DEBUG_HIGHMEM
-       BUG_ON(!pte_none(*(kmap_pte - idx)));
-#endif
-       set_pte(kmap_pte-idx, mk_pte(page, prot));
-       local_flush_tlb_one((unsigned long)vaddr);
-
-       return (void*) vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
-       unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-       int type __maybe_unused;
-
-       if (vaddr < FIXADDR_START)
-               return;
-
-       type = kmap_atomic_idx();
-#ifdef CONFIG_DEBUG_HIGHMEM
-       {
-               int idx = type + KM_TYPE_NR * smp_processor_id();
-
-               BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
-
-               /*
-                * force other mappings to Oops if they'll try to access
-                * this pte without first remap it
-                */
-               pte_clear(&init_mm, vaddr, kmap_pte-idx);
-               local_flush_tlb_one(vaddr);
-       }
-#endif
-       kmap_atomic_idx_pop();
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
-
-/*
- * This is the same as kmap_atomic() but can map memory that doesn't
- * have a struct page associated with it.
- */
-void *kmap_atomic_pfn(unsigned long pfn)
-{
-       unsigned long vaddr;
-       int idx, type;
-
-       preempt_disable();
-       pagefault_disable();
-
-       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, PAGE_KERNEL));
-       flush_tlb_one(vaddr);
-
-       return (void*) vaddr;
-}
-
-void __init kmap_init(void)
-{
-       unsigned long kmap_vstart;
-
-       /* cache the first kmap pte */
-       kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
-       kmap_pte = virt_to_kpte(kmap_vstart);
-}
index 07e84a7..bc80893 100644 (file)
@@ -36,7 +36,6 @@
 #include <asm/cachectl.h>
 #include <asm/cpu.h>
 #include <asm/dma.h>
-#include <asm/kmap_types.h>
 #include <asm/maar.h>
 #include <asm/mmu_context.h>
 #include <asm/sections.h>
@@ -402,9 +401,6 @@ void __init paging_init(void)
 
        pagetable_init();
 
-#ifdef CONFIG_HIGHMEM
-       kmap_init();
-#endif
 #ifdef CONFIG_ZONE_DMA
        max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
 #endif
index f88a12f..c107599 100644 (file)
@@ -157,6 +157,7 @@ config HW_SUPPORT_UNALIGNMENT_ACCESS
 config HIGHMEM
        bool "High Memory Support"
        depends on MMU && !CPU_CACHE_ALIASING
+       select KMAP_LOCAL
        help
          The address space of Andes processors is only 4 Gigabytes large
          and it has to accommodate user address space, kernel address
index 5a4bf11..2fa09a2 100644 (file)
@@ -6,7 +6,7 @@
 
 #ifdef CONFIG_HIGHMEM
 #include <linux/threads.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 #endif
 
 enum fixed_addresses {
@@ -14,7 +14,7 @@ enum fixed_addresses {
        FIX_KMAP_RESERVED,
        FIX_KMAP_BEGIN,
 #ifdef CONFIG_HIGHMEM
-       FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS),
+       FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
 #endif
        FIX_EARLYCON_MEM_BASE,
        __end_of_fixed_addresses
index fe986d0..16159a8 100644 (file)
@@ -5,7 +5,6 @@
 #define _ASM_HIGHMEM_H
 
 #include <asm/proc-fns.h>
-#include <asm/kmap_types.h>
 #include <asm/fixmap.h>
 
 /*
@@ -45,11 +44,22 @@ extern pte_t *pkmap_page_table;
 extern void kmap_init(void);
 
 /*
- * The following functions are already defined by <linux/highmem.h>
- * when CONFIG_HIGHMEM is not set.
+ * FIXME: The below looks broken vs. a kmap_atomic() in task context which
+ * is interupted and another kmap_atomic() happens in interrupt context.
+ * But what do I know about nds32. -- tglx
  */
-#ifdef CONFIG_HIGHMEM
-extern void *kmap_atomic_pfn(unsigned long pfn);
-#endif
+#define arch_kmap_local_post_map(vaddr, pteval)                        \
+       do {                                                    \
+               __nds32__tlbop_inv(vaddr);                      \
+               __nds32__mtsr_dsb(vaddr, NDS32_SR_TLB_VPN);     \
+               __nds32__tlbop_rwr(pteval);                     \
+               __nds32__isb();                                 \
+       } while (0)
+
+#define arch_kmap_local_pre_unmap(vaddr)                       \
+       do {                                                    \
+               __nds32__tlbop_inv(vaddr);                      \
+               __nds32__isb();                                 \
+       } while (0)
 
 #endif
index 897ecaf..14fb2e8 100644 (file)
@@ -3,7 +3,6 @@ obj-y                           := extable.o tlb.o fault.o init.o mmap.o \
                                    mm-nds32.o cacheflush.o proc.o
 
 obj-$(CONFIG_ALIGNMENT_TRAP)   += alignment.o
-obj-$(CONFIG_HIGHMEM)           += highmem.o
 
 ifdef CONFIG_FUNCTION_TRACER
 CFLAGS_REMOVE_proc.o     = $(CC_FLAGS_FTRACE)
diff --git a/arch/nds32/mm/highmem.c b/arch/nds32/mm/highmem.c
deleted file mode 100644 (file)
index 4284cd5..0000000
+++ /dev/null
@@ -1,48 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-// Copyright (C) 2005-2017 Andes Technology Corporation
-
-#include <linux/export.h>
-#include <linux/highmem.h>
-#include <linux/sched.h>
-#include <linux/smp.h>
-#include <linux/interrupt.h>
-#include <linux/memblock.h>
-#include <asm/fixmap.h>
-#include <asm/tlbflush.h>
-
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
-       unsigned int idx;
-       unsigned long vaddr, pte;
-       int type;
-       pte_t *ptep;
-
-       type = kmap_atomic_idx_push();
-
-       idx = type + KM_TYPE_NR * smp_processor_id();
-       vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-       pte = (page_to_pfn(page) << PAGE_SHIFT) | prot;
-       ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr);
-       set_pte(ptep, pte);
-
-       __nds32__tlbop_inv(vaddr);
-       __nds32__mtsr_dsb(vaddr, NDS32_SR_TLB_VPN);
-       __nds32__tlbop_rwr(pte);
-       __nds32__isb();
-       return (void *)vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
-       if (kvaddr >= (void *)FIXADDR_START) {
-               unsigned long vaddr = (unsigned long)kvaddr;
-               pte_t *ptep;
-               kmap_atomic_idx_pop();
-               __nds32__tlbop_inv(vaddr);
-               __nds32__isb();
-               ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr);
-               set_pte(ptep, 0);
-       }
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
index 5e88c35..f3fa02b 100644 (file)
@@ -33,7 +33,6 @@
 #include <asm/io.h>
 #include <asm/tlb.h>
 #include <asm/mmu_context.h>
-#include <asm/kmap_types.h>
 #include <asm/fixmap.h>
 #include <asm/tlbflush.h>
 #include <asm/sections.h>
index a978590..5aed97a 100644 (file)
@@ -15,7 +15,6 @@
 #include <linux/io.h>
 #include <linux/pgtable.h>
 #include <asm/pgalloc.h>
-#include <asm/kmap_types.h>
 #include <asm/fixmap.h>
 #include <asm/bug.h>
 #include <linux/sched.h>
index 7f70395..fad29aa 100644 (file)
@@ -32,7 +32,6 @@ typedef struct {
 DECLARE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
 
 #define __ARCH_IRQ_STAT
-#define __IRQ_STAT(cpu, member) (irq_stat[cpu].member)
 #define inc_irq_stat(member)   this_cpu_inc(irq_stat.member)
 #define __inc_irq_stat(member) __this_cpu_inc(irq_stat.member)
 #define ack_bad_irq(irq) WARN(1, "unexpected IRQ trap at vector %02x\n", irq)
diff --git a/arch/parisc/include/asm/kmap_types.h b/arch/parisc/include/asm/kmap_types.h
deleted file mode 100644 (file)
index 3e70b5c..0000000
+++ /dev/null
@@ -1,13 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_KMAP_TYPES_H
-#define _ASM_KMAP_TYPES_H
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-#define  __WITH_KM_FENCE
-#endif
-
-#include <asm-generic/kmap_types.h>
-
-#undef __WITH_KM_FENCE
-
-#endif
index 5afa0eb..1d3e6f3 100644 (file)
@@ -146,6 +146,7 @@ config PPC
        select ARCH_MIGHT_HAVE_PC_SERIO
        select ARCH_OPTIONAL_KERNEL_RWX         if ARCH_HAS_STRICT_KERNEL_RWX
        select ARCH_SUPPORTS_ATOMIC_RMW
+       select ARCH_SUPPORTS_RT if HAVE_POSIX_CPU_TIMERS_TASK_WORK
        select ARCH_USE_BUILTIN_BSWAP
        select ARCH_USE_CMPXCHG_LOCKREF         if PPC64
        select ARCH_USE_QUEUED_RWLOCKS          if PPC_QUEUED_SPINLOCKS
@@ -230,6 +231,7 @@ config PPC
        select HAVE_HARDLOCKUP_DETECTOR_PERF    if PERF_EVENTS && HAVE_PERF_EVENTS_NMI && !HAVE_HARDLOCKUP_DETECTOR_ARCH
        select HAVE_PERF_REGS
        select HAVE_PERF_USER_STACK_DUMP
+       select HAVE_PREEMPT_LAZY
        select MMU_GATHER_RCU_TABLE_FREE
        select MMU_GATHER_PAGE_SIZE
        select HAVE_REGS_AND_STACK_ACCESS_API
@@ -237,6 +239,7 @@ config PPC
        select HAVE_SYSCALL_TRACEPOINTS
        select HAVE_VIRT_CPU_ACCOUNTING
        select HAVE_IRQ_TIME_ACCOUNTING
+       select HAVE_POSIX_CPU_TIMERS_TASK_WORK  if !KVM
        select HAVE_RSEQ
        select IOMMU_HELPER                     if PPC64
        select IRQ_DOMAIN
@@ -410,6 +413,7 @@ menu "Kernel options"
 config HIGHMEM
        bool "High memory support"
        depends on PPC32
+       select KMAP_LOCAL
 
 source "kernel/Kconfig.hz"
 
index cf091c4..7371f7e 100644 (file)
@@ -5,7 +5,7 @@
 #ifdef __KERNEL__
 #include <linux/compiler.h>
 #include <asm/synch.h>
-#include <linux/bug.h>
+#include <linux/bits.h>
 
 #ifdef __BIG_ENDIAN
 #define BITOFF_CAL(size, off)  ((sizeof(u32) - size - off) * BITS_PER_BYTE)
index 591b2f4..947b5b9 100644 (file)
@@ -20,7 +20,7 @@
 #include <asm/page.h>
 #ifdef CONFIG_HIGHMEM
 #include <linux/threads.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 #endif
 
 #ifdef CONFIG_PPC64
@@ -61,7 +61,7 @@ enum fixed_addresses {
        FIX_EARLY_DEBUG_BASE = FIX_EARLY_DEBUG_TOP+(ALIGN(SZ_128K, PAGE_SIZE)/PAGE_SIZE)-1,
 #ifdef CONFIG_HIGHMEM
        FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
-       FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
+       FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
 #endif
 #ifdef CONFIG_PPC_8xx
        /* For IMMR we need an aligned 512K area */
index 104026f..80a5ae7 100644 (file)
 #ifdef __KERNEL__
 
 #include <linux/interrupt.h>
-#include <asm/kmap_types.h>
 #include <asm/cacheflush.h>
 #include <asm/page.h>
 #include <asm/fixmap.h>
 
-extern pte_t *kmap_pte;
 extern pte_t *pkmap_page_table;
 
 /*
@@ -60,6 +58,11 @@ extern pte_t *pkmap_page_table;
 
 #define flush_cache_kmaps()    flush_cache_all()
 
+#define arch_kmap_local_post_map(vaddr, pteval)        \
+       local_flush_tlb_page(NULL, vaddr)
+#define arch_kmap_local_post_unmap(vaddr)      \
+       local_flush_tlb_page(NULL, vaddr)
+
 #endif /* __KERNEL__ */
 
 #endif /* _ASM_HIGHMEM_H */
diff --git a/arch/powerpc/include/asm/kmap_types.h b/arch/powerpc/include/asm/kmap_types.h
deleted file mode 100644 (file)
index c8fa182..0000000
+++ /dev/null
@@ -1,13 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-or-later */
-#ifndef _ASM_POWERPC_KMAP_TYPES_H
-#define _ASM_POWERPC_KMAP_TYPES_H
-
-#ifdef __KERNEL__
-
-/*
- */
-
-#define KM_TYPE_NR 16
-
-#endif /* __KERNEL__ */
-#endif /* _ASM_POWERPC_KMAP_TYPES_H */
index 0f3cdd8..d45561e 100644 (file)
@@ -2,7 +2,7 @@
 #ifndef _ASM_POWERPC_SIMPLE_SPINLOCK_TYPES_H
 #define _ASM_POWERPC_SIMPLE_SPINLOCK_TYPES_H
 
-#ifndef __LINUX_SPINLOCK_TYPES_H
+#if !defined(__LINUX_SPINLOCK_TYPES_H) && !defined(__LINUX_RT_MUTEX_H)
 # error "please don't include this file directly"
 #endif
 
index c5d742f..cc6922a 100644 (file)
@@ -2,10 +2,6 @@
 #ifndef _ASM_POWERPC_SPINLOCK_TYPES_H
 #define _ASM_POWERPC_SPINLOCK_TYPES_H
 
-#ifndef __LINUX_SPINLOCK_TYPES_H
-# error "please don't include this file directly"
-#endif
-
 #ifdef CONFIG_PPC_QUEUED_SPINLOCKS
 #include <asm-generic/qspinlock_types.h>
 #include <asm-generic/qrwlock_types.h>
index 1c8460e..b1653c1 100644 (file)
@@ -24,7 +24,11 @@ static __always_inline void boot_init_stack_canary(void)
        unsigned long canary;
 
        /* Try to get a semi random initial value. */
+#ifdef CONFIG_PREEMPT_RT
+       canary = (unsigned long)&canary;
+#else
        canary = get_random_canary();
+#endif
        canary ^= mftb();
        canary ^= LINUX_VERSION_CODE;
        canary &= CANARY_MASK;
index 46a210b..0e316b4 100644 (file)
@@ -48,6 +48,8 @@
 struct thread_info {
        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;
@@ -97,11 +99,12 @@ void arch_setup_new_exec(void);
 #define TIF_SINGLESTEP         8       /* singlestepping active */
 #define TIF_NOHZ               9       /* in adaptive nohz mode */
 #define TIF_SECCOMP            10      /* secure computing */
-#define TIF_RESTOREALL         11      /* Restore all regs (implies NOERROR) */
-#define TIF_NOERROR            12      /* Force successful syscall return */
+
+#define TIF_NEED_RESCHED_LAZY  11      /* lazy rescheduling necessary */
+#define TIF_SYSCALL_TRACEPOINT 12      /* syscall tracepoint instrumentation */
+
 #define TIF_NOTIFY_RESUME      13      /* callback before returning to user */
 #define TIF_UPROBE             14      /* breakpointed or single-stepping */
-#define TIF_SYSCALL_TRACEPOINT 15      /* syscall tracepoint instrumentation */
 #define TIF_EMULATE_STACK_STORE        16      /* Is an instruction emulation
                                                for stack store? */
 #define TIF_MEMDIE             17      /* is terminating due to OOM killer */
@@ -110,6 +113,9 @@ void arch_setup_new_exec(void);
 #endif
 #define TIF_POLLING_NRFLAG     19      /* true if poll_idle() is polling TIF_NEED_RESCHED */
 #define TIF_32BIT              20      /* 32 bit binary */
+#define TIF_RESTOREALL         21      /* Restore all regs (implies NOERROR) */
+#define TIF_NOERROR            22      /* Force successful syscall return */
+
 
 /* as above, but as bit values */
 #define _TIF_SYSCALL_TRACE     (1<<TIF_SYSCALL_TRACE)
@@ -129,6 +135,7 @@ void arch_setup_new_exec(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_EMU       (1<<TIF_SYSCALL_EMU)
 #define _TIF_SYSCALL_DOTRACE   (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
                                 _TIF_SECCOMP | _TIF_SYSCALL_TRACEPOINT | \
@@ -136,8 +143,10 @@ void arch_setup_new_exec(void);
 
 #define _TIF_USER_WORK_MASK    (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
                                 _TIF_NOTIFY_RESUME | _TIF_UPROBE | \
-                                _TIF_RESTORE_TM | _TIF_PATCH_PENDING)
+                                _TIF_RESTORE_TM | _TIF_PATCH_PENDING | \
+                                _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 5c12525..5973791 100644 (file)
@@ -189,6 +189,7 @@ int main(void)
        OFFSET(TI_FLAGS, thread_info, flags);
        OFFSET(TI_LOCAL_FLAGS, thread_info, local_flags);
        OFFSET(TI_PREEMPT, thread_info, preempt_count);
+       OFFSET(TI_PREEMPT_LAZY, thread_info, preempt_lazy_count);
 
 #ifdef CONFIG_PPC64
        OFFSET(DCACHEL1BLOCKSIZE, ppc64_caches, l1d.block_size);
index 459f5d0..fc9517a 100644 (file)
@@ -414,7 +414,9 @@ ret_from_syscall:
        mtmsr   r10
        lwz     r9,TI_FLAGS(r2)
        li      r8,-MAX_ERRNO
-       andi.   r0,r9,(_TIF_SYSCALL_DOTRACE|_TIF_SINGLESTEP|_TIF_USER_WORK_MASK|_TIF_PERSYSCALL_MASK)
+       lis     r0,(_TIF_SYSCALL_DOTRACE|_TIF_SINGLESTEP|_TIF_USER_WORK_MASK|_TIF_PERSYSCALL_MASK)@h
+       ori     r0,r0, (_TIF_SYSCALL_DOTRACE|_TIF_SINGLESTEP|_TIF_USER_WORK_MASK|_TIF_PERSYSCALL_MASK)@l
+       and.    r0,r9,r0
        bne-    syscall_exit_work
        cmplw   0,r3,r8
        blt+    syscall_exit_cont
@@ -530,13 +532,13 @@ syscall_dotrace:
        b       syscall_dotrace_cont
 
 syscall_exit_work:
-       andi.   r0,r9,_TIF_RESTOREALL
+       andis.  r0,r9,_TIF_RESTOREALL@h
        beq+    0f
        REST_NVGPRS(r1)
        b       2f
 0:     cmplw   0,r3,r8
        blt+    1f
-       andi.   r0,r9,_TIF_NOERROR
+       andis.  r0,r9,_TIF_NOERROR@h
        bne-    1f
        lwz     r11,_CCR(r1)                    /* Load CR */
        neg     r3,r3
@@ -545,12 +547,12 @@ syscall_exit_work:
 
 1:     stw     r6,RESULT(r1)   /* Save result */
        stw     r3,GPR3(r1)     /* Update return value */
-2:     andi.   r0,r9,(_TIF_PERSYSCALL_MASK)
+2:     andis.  r0,r9,(_TIF_PERSYSCALL_MASK)@h
        beq     4f
 
        /* Clear per-syscall TIF flags if any are set.  */
 
-       li      r11,_TIF_PERSYSCALL_MASK
+       lis     r11,(_TIF_PERSYSCALL_MASK)@h
        addi    r12,r2,TI_FLAGS
 3:     lwarx   r8,0,r12
        andc    r8,r8,r11
@@ -927,7 +929,14 @@ resume_kernel:
        cmpwi   0,r0,0          /* if non-zero, just restore regs and return */
        bne     restore_kuap
        andi.   r8,r8,_TIF_NEED_RESCHED
+       bne+    1f
+       lwz     r0,TI_PREEMPT_LAZY(r2)
+       cmpwi   0,r0,0          /* if non-zero, just restore regs and return */
+       bne     restore_kuap
+       lwz     r0,TI_FLAGS(r2)
+       andi.   r0,r0,_TIF_NEED_RESCHED_LAZY
        beq+    restore_kuap
+1:
        lwz     r3,_MSR(r1)
        andi.   r0,r3,MSR_EE    /* interrupts off? */
        beq     restore_kuap    /* don't schedule if so */
@@ -1248,7 +1257,7 @@ 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 */
@@ -1267,7 +1276,7 @@ recheck:
        LOAD_REG_IMMEDIATE(r10,MSR_KERNEL)
        mtmsr   r10             /* disable interrupts */
        lwz     r9,TI_FLAGS(r2)
-       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 f579ce4..715ff29 100644 (file)
@@ -1080,7 +1080,7 @@ _GLOBAL(ret_from_except_lite)
        li      r10, -1
        mtspr   SPRN_DBSR,r10
        b       restore
-1:     andi.   r0,r4,_TIF_NEED_RESCHED
+1:     andi.   r0,r4,_TIF_NEED_RESCHED_MASK
        beq     2f
        bl      restore_interrupts
        SCHEDULE_USER
@@ -1132,12 +1132,20 @@ resume_kernel:
        bne-    0b
 1:
 
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPTION
        /* 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   cr0,r8,0
        bne     restore
        ld      r0,SOFTE(r1)
@@ -1158,7 +1166,7 @@ resume_kernel:
         * interrupted after loading SRR0/1.
         */
        wrteei  0
-#endif /* CONFIG_PREEMPT */
+#endif /* CONFIG_PREEMPTION */
 
 restore:
        /*
index e8a5484..5ad4f27 100644 (file)
@@ -753,10 +753,12 @@ void *mcheckirq_ctx[NR_CPUS] __read_mostly;
 void *softirq_ctx[NR_CPUS] __read_mostly;
 void *hardirq_ctx[NR_CPUS] __read_mostly;
 
+#ifndef CONFIG_PREEMPT_RT
 void do_softirq_own_stack(void)
 {
        call_do_softirq(softirq_ctx[smp_processor_id()]);
 }
+#endif
 
 irq_hw_number_t virq_to_hw(unsigned int virq)
 {
index 717e658..08ee95a 100644 (file)
@@ -31,6 +31,7 @@
  * We store the saved ksp_limit in the unused part
  * of the STACK_FRAME_OVERHEAD
  */
+#ifndef CONFIG_PREEMPT_RT
 _GLOBAL(call_do_softirq)
        mflr    r0
        stw     r0,4(r1)
@@ -46,6 +47,7 @@ _GLOBAL(call_do_softirq)
        stw     r10,THREAD+KSP_LIMIT(r2)
        mtlr    r0
        blr
+#endif
 
 /*
  * void call_do_irq(struct pt_regs *regs, void *sp);
index 0704658..a6b33f7 100644 (file)
@@ -27,6 +27,7 @@
 
        .text
 
+#ifndef CONFIG_PREEMPT_RT
 _GLOBAL(call_do_softirq)
        mflr    r0
        std     r0,16(r1)
@@ -37,6 +38,7 @@ _GLOBAL(call_do_softirq)
        ld      r0,16(r1)
        mtlr    r0
        blr
+#endif
 
 _GLOBAL(call_do_irq)
        mflr    r0
index 532f226..1ef55f4 100644 (file)
@@ -73,7 +73,8 @@ static const char *nvram_os_partitions[] = {
 };
 
 static void oops_to_nvram(struct kmsg_dumper *dumper,
-                         enum kmsg_dump_reason reason);
+                         enum kmsg_dump_reason reason,
+                         struct kmsg_dumper_iter *iter);
 
 static struct kmsg_dumper nvram_kmsg_dumper = {
        .dump = oops_to_nvram
@@ -643,7 +644,8 @@ void __init nvram_init_oops_partition(int rtas_partition_exists)
  * partition.  If that's too much, go back and capture uncompressed text.
  */
 static void oops_to_nvram(struct kmsg_dumper *dumper,
-                         enum kmsg_dump_reason reason)
+                         enum kmsg_dump_reason reason,
+                         struct kmsg_dumper_iter *iter)
 {
        struct oops_log_info *oops_hdr = (struct oops_log_info *)oops_buf;
        static unsigned int oops_count = 0;
@@ -681,13 +683,13 @@ static void oops_to_nvram(struct kmsg_dumper *dumper,
                return;
 
        if (big_oops_buf) {
-               kmsg_dump_get_buffer(dumper, false,
+               kmsg_dump_get_buffer(iter, false,
                                     big_oops_buf, big_oops_buf_sz, &text_len);
                rc = zip_oops(text_len);
        }
        if (rc != 0) {
-               kmsg_dump_rewind(dumper);
-               kmsg_dump_get_buffer(dumper, false,
+               kmsg_dump_rewind(iter);
+               kmsg_dump_get_buffer(iter, false,
                                     oops_data, oops_data_sz, &text_len);
                err_type = ERR_TYPE_KERNEL_PANIC;
                oops_hdr->version = cpu_to_be16(OOPS_HDR_VERSION);
index 310bcd7..ae3212d 100644 (file)
@@ -193,7 +193,7 @@ again:
        ti_flags = READ_ONCE(*ti_flagsp);
        while (unlikely(ti_flags & (_TIF_USER_WORK_MASK & ~_TIF_RESTORE_TM))) {
                local_irq_enable();
-               if (ti_flags & _TIF_NEED_RESCHED) {
+               if (ti_flags & _TIF_NEED_RESCHED_MASK) {
                        schedule();
                } else {
                        /*
@@ -277,7 +277,7 @@ again:
        ti_flags = READ_ONCE(*ti_flagsp);
        while (unlikely(ti_flags & (_TIF_USER_WORK_MASK & ~_TIF_RESTORE_TM))) {
                local_irq_enable(); /* returning to user: may enable */
-               if (ti_flags & _TIF_NEED_RESCHED) {
+               if (ti_flags & _TIF_NEED_RESCHED_MASK) {
                        schedule();
                } else {
                        if (ti_flags & _TIF_SIGPENDING)
@@ -361,11 +361,15 @@ notrace unsigned long interrupt_exit_kernel_prepare(struct pt_regs *regs, unsign
                /* Returning to a kernel context with local irqs enabled. */
                WARN_ON_ONCE(!(regs->msr & MSR_EE));
 again:
-               if (IS_ENABLED(CONFIG_PREEMPT)) {
+               if (IS_ENABLED(CONFIG_PREEMPTION)) {
                        /* Return to preemptible kernel context */
                        if (unlikely(*ti_flagsp & _TIF_NEED_RESCHED)) {
                                if (preempt_count() == 0)
                                        preempt_schedule_irq();
+                       } else if (unlikely(*ti_flagsp & _TIF_NEED_RESCHED_LAZY)) {
+                               if ((preempt_count() == 0) &&
+                                   (current_thread_info()->preempt_lazy_count == 0))
+                                       preempt_schedule_irq();
                        }
                }
 
index 1d20f0f..7e0a497 100644 (file)
@@ -312,12 +312,11 @@ static unsigned long vtime_delta_scaled(struct cpu_accounting_data *acct,
        return stime_scaled;
 }
 
-static unsigned long vtime_delta(struct task_struct *tsk,
+static unsigned long vtime_delta(struct cpu_accounting_data *acct,
                                 unsigned long *stime_scaled,
                                 unsigned long *steal_time)
 {
        unsigned long now, stime;
-       struct cpu_accounting_data *acct = get_accounting(tsk);
 
        WARN_ON_ONCE(!irqs_disabled());
 
@@ -332,29 +331,30 @@ static unsigned long vtime_delta(struct task_struct *tsk,
        return stime;
 }
 
+static void vtime_delta_kernel(struct cpu_accounting_data *acct,
+                              unsigned long *stime, unsigned long *stime_scaled)
+{
+       unsigned long steal_time;
+
+       *stime = vtime_delta(acct, stime_scaled, &steal_time);
+       *stime -= min(*stime, steal_time);
+       acct->steal_time += steal_time;
+}
+
 void vtime_account_kernel(struct task_struct *tsk)
 {
-       unsigned long stime, stime_scaled, steal_time;
        struct cpu_accounting_data *acct = get_accounting(tsk);
+       unsigned long stime, stime_scaled;
 
-       stime = vtime_delta(tsk, &stime_scaled, &steal_time);
-
-       stime -= min(stime, steal_time);
-       acct->steal_time += steal_time;
+       vtime_delta_kernel(acct, &stime, &stime_scaled);
 
-       if ((tsk->flags & PF_VCPU) && !irq_count()) {
+       if (tsk->flags & PF_VCPU) {
                acct->gtime += stime;
 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
                acct->utime_scaled += stime_scaled;
 #endif
        } else {
-               if (hardirq_count())
-                       acct->hardirq_time += stime;
-               else if (in_serving_softirq())
-                       acct->softirq_time += stime;
-               else
-                       acct->stime += stime;
-
+               acct->stime += stime;
 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
                acct->stime_scaled += stime_scaled;
 #endif
@@ -367,10 +367,34 @@ void vtime_account_idle(struct task_struct *tsk)
        unsigned long stime, stime_scaled, steal_time;
        struct cpu_accounting_data *acct = get_accounting(tsk);
 
-       stime = vtime_delta(tsk, &stime_scaled, &steal_time);
+       stime = vtime_delta(acct, &stime_scaled, &steal_time);
        acct->idle_time += stime + steal_time;
 }
 
+static void vtime_account_irq_field(struct cpu_accounting_data *acct,
+                                   unsigned long *field)
+{
+       unsigned long stime, stime_scaled;
+
+       vtime_delta_kernel(acct, &stime, &stime_scaled);
+       *field += stime;
+#ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
+       acct->stime_scaled += stime_scaled;
+#endif
+}
+
+void vtime_account_softirq(struct task_struct *tsk)
+{
+       struct cpu_accounting_data *acct = get_accounting(tsk);
+       vtime_account_irq_field(acct, &acct->softirq_time);
+}
+
+void vtime_account_hardirq(struct task_struct *tsk)
+{
+       struct cpu_accounting_data *acct = get_accounting(tsk);
+       vtime_account_irq_field(acct, &acct->hardirq_time);
+}
+
 static void vtime_flush_scaled(struct task_struct *tsk,
                               struct cpu_accounting_data *acct)
 {
index 069d451..8eaa8c2 100644 (file)
@@ -170,7 +170,6 @@ extern void panic_flush_kmsg_start(void)
 
 extern void panic_flush_kmsg_end(void)
 {
-       printk_safe_flush_on_panic();
        kmsg_dump(KMSG_DUMP_PANIC);
        bust_spinlocks(0);
        debug_locks_off();
@@ -260,12 +259,17 @@ static char *get_mmu_str(void)
 
 static int __die(const char *str, struct pt_regs *regs, long err)
 {
+       const char *pr = "";
+
        printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter);
 
+       if (IS_ENABLED(CONFIG_PREEMPTION))
+               pr = IS_ENABLED(CONFIG_PREEMPT_RT) ? " PREEMPT_RT" : " PREEMPT";
+
        printk("%s PAGE_SIZE=%luK%s%s%s%s%s%s %s\n",
               IS_ENABLED(CONFIG_CPU_LITTLE_ENDIAN) ? "LE" : "BE",
               PAGE_SIZE / 1024, get_mmu_str(),
-              IS_ENABLED(CONFIG_PREEMPT) ? " PREEMPT" : "",
+              pr,
               IS_ENABLED(CONFIG_SMP) ? " SMP" : "",
               IS_ENABLED(CONFIG_SMP) ? (" NR_CPUS=" __stringify(NR_CPUS)) : "",
               debug_pagealloc_enabled() ? " DEBUG_PAGEALLOC" : "",
index 75b2a6c..db40e20 100644 (file)
@@ -185,11 +185,6 @@ static void watchdog_smp_panic(int cpu, u64 tb)
 
        wd_smp_unlock(&flags);
 
-       printk_safe_flush();
-       /*
-        * printk_safe_flush() seems to require another print
-        * before anything actually goes out to console.
-        */
        if (sysctl_hardlockup_all_cpu_backtrace)
                trigger_allbutself_cpu_backtrace();
 
index c9a8898..d488311 100644 (file)
@@ -311,9 +311,6 @@ void default_machine_crash_shutdown(struct pt_regs *regs)
        unsigned int i;
        int (*old_handler)(struct pt_regs *regs);
 
-       /* Avoid hardlocking with irresponsive CPU holding logbuf_lock */
-       printk_nmi_enter();
-
        /*
         * This function is only called after the system
         * has panicked or is otherwise in a critical state.
index 549591d..efb5bfe 100644 (file)
@@ -178,6 +178,7 @@ config KVM_E500MC
 config KVM_MPIC
        bool "KVM in-kernel MPIC emulation"
        depends on KVM && E500
+       depends on !PREEMPT_RT
        select HAVE_KVM_IRQCHIP
        select HAVE_KVM_IRQFD
        select HAVE_KVM_IRQ_ROUTING
index 55b4a8b..3b4e9e4 100644 (file)
@@ -16,7 +16,6 @@ obj-$(CONFIG_NEED_MULTIPLE_NODES) += numa.o
 obj-$(CONFIG_PPC_MM_SLICES)    += slice.o
 obj-$(CONFIG_HUGETLB_PAGE)     += hugetlbpage.o
 obj-$(CONFIG_NOT_COHERENT_CACHE) += dma-noncoherent.o
-obj-$(CONFIG_HIGHMEM)          += highmem.o
 obj-$(CONFIG_PPC_COPRO_BASE)   += copro_fault.o
 obj-$(CONFIG_PPC_PTDUMP)       += ptdump/
 obj-$(CONFIG_KASAN)            += kasan/
diff --git a/arch/powerpc/mm/highmem.c b/arch/powerpc/mm/highmem.c
deleted file mode 100644 (file)
index 624b443..0000000
+++ /dev/null
@@ -1,67 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * highmem.c: virtual kernel memory mappings for high memory
- *
- * PowerPC version, stolen from the i386 version.
- *
- * Used in CONFIG_HIGHMEM systems for memory pages which
- * are not addressable by direct kernel virtual addresses.
- *
- * Copyright (C) 1999 Gerhard Wichert, Siemens AG
- *                   Gerhard.Wichert@pdb.siemens.de
- *
- *
- * Redesigned the x86 32-bit VM architecture to deal with
- * up to 16 Terrabyte physical memory. With current x86 CPUs
- * we now support up to 64 Gigabytes physical RAM.
- *
- * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com>
- *
- * Reworked for PowerPC by various contributors. Moved from
- * highmem.h by Benjamin Herrenschmidt (c) 2009 IBM Corp.
- */
-
-#include <linux/highmem.h>
-#include <linux/module.h>
-
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
-       unsigned long vaddr;
-       int idx, type;
-
-       type = kmap_atomic_idx_push();
-       idx = type + KM_TYPE_NR*smp_processor_id();
-       vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-       WARN_ON(IS_ENABLED(CONFIG_DEBUG_HIGHMEM) && !pte_none(*(kmap_pte - idx)));
-       __set_pte_at(&init_mm, vaddr, kmap_pte-idx, mk_pte(page, prot), 1);
-       local_flush_tlb_page(NULL, vaddr);
-
-       return (void*) vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
-       unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-
-       if (vaddr < __fix_to_virt(FIX_KMAP_END))
-               return;
-
-       if (IS_ENABLED(CONFIG_DEBUG_HIGHMEM)) {
-               int type = kmap_atomic_idx();
-               unsigned int idx;
-
-               idx = type + KM_TYPE_NR * smp_processor_id();
-               WARN_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
-
-               /*
-                * force other mappings to Oops if they'll try to access
-                * this pte without first remap it
-                */
-               pte_clear(&init_mm, vaddr, kmap_pte-idx);
-               local_flush_tlb_page(NULL, vaddr);
-       }
-
-       kmap_atomic_idx_pop();
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
index 22eb1c7..1b74565 100644 (file)
 unsigned long long memory_limit;
 bool init_mem_is_free;
 
-#ifdef CONFIG_HIGHMEM
-pte_t *kmap_pte;
-EXPORT_SYMBOL(kmap_pte);
-#endif
-
 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
                              unsigned long size, pgprot_t vma_prot)
 {
@@ -236,8 +231,6 @@ void __init paging_init(void)
 
        map_kernel_page(PKMAP_BASE, 0, __pgprot(0));    /* XXX gross */
        pkmap_page_table = virt_to_kpte(PKMAP_BASE);
-
-       kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
 #endif /* CONFIG_HIGHMEM */
 
        printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n",
index 6c3bc4b..ec86284 100644 (file)
@@ -20,7 +20,8 @@
  * message, it just ensures that OPAL completely flushes the console buffer.
  */
 static void kmsg_dump_opal_console_flush(struct kmsg_dumper *dumper,
-                                    enum kmsg_dump_reason reason)
+                                        enum kmsg_dump_reason reason,
+                                        struct kmsg_dumper_iter *iter)
 {
        /*
         * Outside of a panic context the pollers will continue to run,
index 245f1f8..f05555d 100644 (file)
@@ -24,6 +24,7 @@
 #include <linux/of.h>
 #include <linux/iommu.h>
 #include <linux/rculist.h>
+#include <linux/local_lock.h>
 #include <asm/io.h>
 #include <asm/prom.h>
 #include <asm/rtas.h>
@@ -190,7 +191,13 @@ static int tce_build_pSeriesLP(unsigned long liobn, long tcenum, long tceshift,
        return ret;
 }
 
-static DEFINE_PER_CPU(__be64 *, tce_page);
+struct tce_page {
+       __be64 * page;
+       local_lock_t lock;
+};
+static DEFINE_PER_CPU(struct tce_page, tce_page) = {
+       .lock = INIT_LOCAL_LOCK(lock),
+};
 
 static int tce_buildmulti_pSeriesLP(struct iommu_table *tbl, long tcenum,
                                     long npages, unsigned long uaddr,
@@ -212,9 +219,10 @@ static int tce_buildmulti_pSeriesLP(struct iommu_table *tbl, long tcenum,
                                           direction, attrs);
        }
 
-       local_irq_save(flags);  /* to protect tcep and the page behind it */
+       /* to protect tcep and the page behind it */
+       local_lock_irqsave(&tce_page.lock, flags);
 
-       tcep = __this_cpu_read(tce_page);
+       tcep = __this_cpu_read(tce_page.page);
 
        /* This is safe to do since interrupts are off when we're called
         * from iommu_alloc{,_sg}()
@@ -223,12 +231,12 @@ static int tce_buildmulti_pSeriesLP(struct iommu_table *tbl, long tcenum,
                tcep = (__be64 *)__get_free_page(GFP_ATOMIC);
                /* If allocation fails, fall back to the loop implementation */
                if (!tcep) {
-                       local_irq_restore(flags);
+                       local_unlock_irqrestore(&tce_page.lock, flags);
                        return tce_build_pSeriesLP(tbl->it_index, tcenum,
                                        tbl->it_page_shift,
                                        npages, uaddr, direction, attrs);
                }
-               __this_cpu_write(tce_page, tcep);
+               __this_cpu_write(tce_page.page, tcep);
        }
 
        rpn = __pa(uaddr) >> TCE_SHIFT;
@@ -258,7 +266,7 @@ static int tce_buildmulti_pSeriesLP(struct iommu_table *tbl, long tcenum,
                tcenum += limit;
        } while (npages > 0 && !rc);
 
-       local_irq_restore(flags);
+       local_unlock_irqrestore(&tce_page.lock, flags);
 
        if (unlikely(rc == H_NOT_ENOUGH_RESOURCES)) {
                ret = (int)rc;
@@ -429,16 +437,17 @@ static int tce_setrange_multi_pSeriesLP(unsigned long start_pfn,
                                DMA_BIDIRECTIONAL, 0);
        }
 
-       local_irq_disable();    /* to protect tcep and the page behind it */
-       tcep = __this_cpu_read(tce_page);
+       /* to protect tcep and the page behind it */
+       local_lock_irq(&tce_page.lock);
+       tcep = __this_cpu_read(tce_page.page);
 
        if (!tcep) {
                tcep = (__be64 *)__get_free_page(GFP_ATOMIC);
                if (!tcep) {
-                       local_irq_enable();
+                       local_unlock_irq(&tce_page.lock);
                        return -ENOMEM;
                }
-               __this_cpu_write(tce_page, tcep);
+               __this_cpu_write(tce_page.page, tcep);
        }
 
        proto_tce = TCE_PCI_READ | TCE_PCI_WRITE;
@@ -481,7 +490,7 @@ static int tce_setrange_multi_pSeriesLP(unsigned long start_pfn,
 
        /* error cleanup: caller will clear whole range */
 
-       local_irq_enable();
+       local_unlock_irq(&tce_page.lock);
        return rc;
 }
 
index 5559edf..d62b8e0 100644 (file)
@@ -3005,7 +3005,7 @@ print_address(unsigned long addr)
 static void
 dump_log_buf(void)
 {
-       struct kmsg_dumper dumper = { .active = 1 };
+       struct kmsg_dumper_iter iter = { .active = 1 };
        unsigned char buf[128];
        size_t len;
 
@@ -3017,9 +3017,9 @@ dump_log_buf(void)
        catch_memory_errors = 1;
        sync();
 
-       kmsg_dump_rewind_nolock(&dumper);
+       kmsg_dump_rewind(&iter);
        xmon_start_pagination();
-       while (kmsg_dump_get_line_nolock(&dumper, false, buf, sizeof(buf), &len)) {
+       while (kmsg_dump_get_line(&iter, false, buf, sizeof(buf), &len)) {
                buf[len] = '\0';
                printf("%s", buf);
        }
index 896b68e..54a4e77 100644 (file)
@@ -183,6 +183,7 @@ config S390
        select HAVE_RSEQ
        select HAVE_SYSCALL_TRACEPOINTS
        select HAVE_VIRT_CPU_ACCOUNTING
+       select HAVE_VIRT_CPU_ACCOUNTING_IDLE
        select IOMMU_HELPER             if PCI
        select IOMMU_SUPPORT            if PCI
        select MODULES_USE_ELF_RELA
index cfed272..8e28e81 100644 (file)
@@ -2,10 +2,6 @@
 #ifndef __ASM_SPINLOCK_TYPES_H
 #define __ASM_SPINLOCK_TYPES_H
 
-#ifndef __LINUX_SPINLOCK_TYPES_H
-# error "please don't include this file directly"
-#endif
-
 typedef struct {
        int lock;
 } __attribute__ ((aligned (4))) arch_spinlock_t;
index 3622d4e..fac6a67 100644 (file)
@@ -2,7 +2,6 @@
 #ifndef _S390_VTIME_H
 #define _S390_VTIME_H
 
-#define __ARCH_HAS_VTIME_ACCOUNT
 #define __ARCH_HAS_VTIME_TASK_SWITCH
 
 #endif /* _S390_VTIME_H */
index 579ec3a..9b3c597 100644 (file)
@@ -223,35 +223,50 @@ void vtime_flush(struct task_struct *tsk)
        S390_lowcore.avg_steal_timer = avg_steal;
 }
 
+static u64 vtime_delta(void)
+{
+       u64 timer = S390_lowcore.last_update_timer;
+
+       S390_lowcore.last_update_timer = get_vtimer();
+
+       return timer - S390_lowcore.last_update_timer;
+}
+
 /*
  * Update process times based on virtual cpu times stored by entry.S
  * to the lowcore fields user_timer, system_timer & steal_clock.
  */
-void vtime_account_irq_enter(struct task_struct *tsk)
+void vtime_account_kernel(struct task_struct *tsk)
 {
-       u64 timer;
-
-       timer = S390_lowcore.last_update_timer;
-       S390_lowcore.last_update_timer = get_vtimer();
-       timer -= S390_lowcore.last_update_timer;
+       u64 delta = vtime_delta();
 
-       if ((tsk->flags & PF_VCPU) && (irq_count() == 0))
-               S390_lowcore.guest_timer += timer;
-       else if (hardirq_count())
-               S390_lowcore.hardirq_timer += timer;
-       else if (in_serving_softirq())
-               S390_lowcore.softirq_timer += timer;
+       if (tsk->flags & PF_VCPU)
+               S390_lowcore.guest_timer += delta;
        else
-               S390_lowcore.system_timer += timer;
+               S390_lowcore.system_timer += delta;
 
-       virt_timer_forward(timer);
+       virt_timer_forward(delta);
 }
-EXPORT_SYMBOL_GPL(vtime_account_irq_enter);
-
-void vtime_account_kernel(struct task_struct *tsk)
-__attribute__((alias("vtime_account_irq_enter")));
 EXPORT_SYMBOL_GPL(vtime_account_kernel);
 
+void vtime_account_softirq(struct task_struct *tsk)
+{
+       u64 delta = vtime_delta();
+
+       S390_lowcore.softirq_timer += delta;
+
+       virt_timer_forward(delta);
+}
+
+void vtime_account_hardirq(struct task_struct *tsk)
+{
+       u64 delta = vtime_delta();
+
+       S390_lowcore.hardirq_timer += delta;
+
+       virt_timer_forward(delta);
+}
+
 /*
  * Sorted add to a list. List is linear searched until first bigger
  * element is found.
index f38adc1..b07fbc7 100644 (file)
@@ -13,9 +13,6 @@
 #include <linux/kernel.h>
 #include <linux/threads.h>
 #include <asm/page.h>
-#ifdef CONFIG_HIGHMEM
-#include <asm/kmap_types.h>
-#endif
 
 /*
  * Here we define all the compile-time 'special' virtual
@@ -53,11 +50,6 @@ enum fixed_addresses {
        FIX_CMAP_BEGIN,
        FIX_CMAP_END = FIX_CMAP_BEGIN + (FIX_N_COLOURS * NR_CPUS) - 1,
 
-#ifdef CONFIG_HIGHMEM
-       FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
-       FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS) - 1,
-#endif
-
 #ifdef CONFIG_IOREMAP_FIXED
        /*
         * FIX_IOREMAP entries are useful for mapping physical address
index edaea35..9fe4495 100644 (file)
@@ -2,16 +2,10 @@
 #ifndef __ASM_SH_HARDIRQ_H
 #define __ASM_SH_HARDIRQ_H
 
-#include <linux/threads.h>
-#include <linux/irq.h>
-
-typedef struct {
-       unsigned int __softirq_pending;
-       unsigned int __nmi_count;               /* arch dependent */
-} ____cacheline_aligned irq_cpustat_t;
-
-#include <linux/irq_cpustat.h> /* Standard mappings for irq_cpustat_t above */
-
 extern void ack_bad_irq(unsigned int irq);
+#define ack_bad_irq ack_bad_irq
+#define ARCH_WANTS_NMI_IRQSTAT
+
+#include <asm-generic/hardirq.h>
 
 #endif /* __ASM_SH_HARDIRQ_H */
diff --git a/arch/sh/include/asm/kmap_types.h b/arch/sh/include/asm/kmap_types.h
deleted file mode 100644 (file)
index b78107f..0000000
+++ /dev/null
@@ -1,15 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __SH_KMAP_TYPES_H
-#define __SH_KMAP_TYPES_H
-
-/* Dummy header just to define km_type. */
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-#define  __WITH_KM_FENCE
-#endif
-
-#include <asm-generic/kmap_types.h>
-
-#undef __WITH_KM_FENCE
-
-#endif
index e82369f..22ca9a9 100644 (file)
@@ -2,10 +2,6 @@
 #ifndef __ASM_SH_SPINLOCK_TYPES_H
 #define __ASM_SH_SPINLOCK_TYPES_H
 
-#ifndef __LINUX_SPINLOCK_TYPES_H
-# error "please don't include this file directly"
-#endif
-
 typedef struct {
        volatile unsigned int lock;
 } arch_spinlock_t;
index 5717c7c..5db7af5 100644 (file)
@@ -44,7 +44,7 @@ int arch_show_interrupts(struct seq_file *p, int prec)
 
        seq_printf(p, "%*s: ", prec, "NMI");
        for_each_online_cpu(j)
-               seq_printf(p, "%10u ", nmi_count(j));
+               seq_printf(p, "%10u ", per_cpu(irq_stat.__nmi_count, j));
        seq_printf(p, "  Non-maskable interrupts\n");
 
        seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
@@ -148,6 +148,7 @@ void irq_ctx_exit(int cpu)
        hardirq_ctx[cpu] = NULL;
 }
 
+#ifndef CONFIG_PREEMPT_RT
 void do_softirq_own_stack(void)
 {
        struct thread_info *curctx;
@@ -175,6 +176,7 @@ 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 9c3d32b..f5beecd 100644 (file)
@@ -186,7 +186,7 @@ BUILD_TRAP_HANDLER(nmi)
        arch_ftrace_nmi_enter();
 
        nmi_enter();
-       nmi_count(cpu)++;
+       this_cpu_inc(irq_stat.__nmi_count);
 
        switch (notify_die(DIE_NMI, "NMI", regs, 0, vec & 0xff, SIGINT)) {
        case NOTIFY_OK:
index 3348e0c..0db6919 100644 (file)
@@ -362,9 +362,6 @@ void __init mem_init(void)
        mem_init_print_info(NULL);
        pr_info("virtual kernel memory layout:\n"
                "    fixmap  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
-#ifdef CONFIG_HIGHMEM
-               "    pkmap   : 0x%08lx - 0x%08lx   (%4ld kB)\n"
-#endif
                "    vmalloc : 0x%08lx - 0x%08lx   (%4ld MB)\n"
                "    lowmem  : 0x%08lx - 0x%08lx   (%4ld MB) (cached)\n"
 #ifdef CONFIG_UNCACHED_MAPPING
@@ -376,11 +373,6 @@ void __init mem_init(void)
                FIXADDR_START, FIXADDR_TOP,
                (FIXADDR_TOP - FIXADDR_START) >> 10,
 
-#ifdef CONFIG_HIGHMEM
-               PKMAP_BASE, PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
-               (LAST_PKMAP*PAGE_SIZE) >> 10,
-#endif
-
                (unsigned long)VMALLOC_START, VMALLOC_END,
                (VMALLOC_END - VMALLOC_START) >> 20,
 
index 530b7ec..a38d00d 100644 (file)
@@ -139,6 +139,7 @@ config MMU
 config HIGHMEM
        bool
        default y if SPARC32
+       select KMAP_LOCAL
 
 config ZONE_DMA
        bool
index 6c35f0d..8751162 100644 (file)
@@ -24,7 +24,6 @@
 #include <linux/interrupt.h>
 #include <linux/pgtable.h>
 #include <asm/vaddrs.h>
-#include <asm/kmap_types.h>
 #include <asm/pgtsrmmu.h>
 
 /* declarations for highmem.c */
@@ -33,8 +32,6 @@ extern unsigned long highstart_pfn, highend_pfn;
 #define kmap_prot __pgprot(SRMMU_ET_PTE | SRMMU_PRIV | SRMMU_CACHE)
 extern pte_t *pkmap_page_table;
 
-void kmap_init(void) __init;
-
 /*
  * Right now we initialize only a single pte table. It can be extended
  * easily, subsequent pte tables have to be allocated in one physical
@@ -53,6 +50,11 @@ void kmap_init(void) __init;
 
 #define flush_cache_kmaps()    flush_cache_all()
 
+/* FIXME: Use __flush_tlb_one(vaddr) instead of flush_cache_all() -- Anton */
+#define arch_kmap_local_post_map(vaddr, pteval)        flush_cache_all()
+#define arch_kmap_local_post_unmap(vaddr)      flush_cache_all()
+
+
 #endif /* __KERNEL__ */
 
 #endif /* _ASM_HIGHMEM_H */
diff --git a/arch/sparc/include/asm/kmap_types.h b/arch/sparc/include/asm/kmap_types.h
deleted file mode 100644 (file)
index 55a99b6..0000000
+++ /dev/null
@@ -1,11 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_KMAP_TYPES_H
-#define _ASM_KMAP_TYPES_H
-
-/* Dummy header just to define km_type.  None of this
- * is actually used on sparc.  -DaveM
- */
-
-#include <asm-generic/kmap_types.h>
-
-#endif
index 84d054b..4fec034 100644 (file)
 #define SRMMU_NOCACHE_ALCRATIO 64      /* 256 pages per 64MB of system RAM */
 
 #ifndef __ASSEMBLY__
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 
 enum fixed_addresses {
        FIX_HOLE,
 #ifdef CONFIG_HIGHMEM
        FIX_KMAP_BEGIN,
-       FIX_KMAP_END = (KM_TYPE_NR * NR_CPUS),
+       FIX_KMAP_END = (KM_MAX_IDX * NR_CPUS),
 #endif
        __end_of_fixed_addresses
 };
index 3ec9f14..eb21682 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
 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 b078205..68db1f8 100644 (file)
@@ -15,6 +15,3 @@ obj-$(CONFIG_SPARC32)   += leon_mm.o
 
 # Only used by sparc64
 obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
-
-# Only used by sparc32
-obj-$(CONFIG_HIGHMEM)   += highmem.o
diff --git a/arch/sparc/mm/highmem.c b/arch/sparc/mm/highmem.c
deleted file mode 100644 (file)
index 8f2a2af..0000000
+++ /dev/null
@@ -1,115 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- *  highmem.c: virtual kernel memory mappings for high memory
- *
- *  Provides kernel-static versions of atomic kmap functions originally
- *  found as inlines in include/asm-sparc/highmem.h.  These became
- *  needed as kmap_atomic() and kunmap_atomic() started getting
- *  called from within modules.
- *  -- Tomas Szepe <szepe@pinerecords.com>, September 2002
- *
- *  But kmap_atomic() and kunmap_atomic() cannot be inlined in
- *  modules because they are loaded with btfixup-ped functions.
- */
-
-/*
- * The use of kmap_atomic/kunmap_atomic is discouraged - kmap/kunmap
- * gives a more generic (and caching) interface. But kmap_atomic can
- * be used in IRQ contexts, so in some (very limited) cases we need it.
- *
- * XXX This is an old text. Actually, it's good to use atomic kmaps,
- * provided you remember that they are atomic and not try to sleep
- * with a kmap taken, much like a spinlock. Non-atomic kmaps are
- * shared by CPUs, and so precious, and establishing them requires IPI.
- * Atomic kmaps are lightweight and we may have NCPUS more of them.
- */
-#include <linux/highmem.h>
-#include <linux/export.h>
-#include <linux/mm.h>
-
-#include <asm/cacheflush.h>
-#include <asm/tlbflush.h>
-#include <asm/vaddrs.h>
-
-static pte_t *kmap_pte;
-
-void __init kmap_init(void)
-{
-       unsigned long address = __fix_to_virt(FIX_KMAP_BEGIN);
-
-        /* cache the first kmap pte */
-        kmap_pte = virt_to_kpte(address);
-}
-
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
-       unsigned long vaddr;
-       long idx, type;
-
-       type = kmap_atomic_idx_push();
-       idx = type + KM_TYPE_NR*smp_processor_id();
-       vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-
-/* XXX Fix - Anton */
-#if 0
-       __flush_cache_one(vaddr);
-#else
-       flush_cache_all();
-#endif
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-       BUG_ON(!pte_none(*(kmap_pte-idx)));
-#endif
-       set_pte(kmap_pte-idx, mk_pte(page, prot));
-/* XXX Fix - Anton */
-#if 0
-       __flush_tlb_one(vaddr);
-#else
-       flush_tlb_all();
-#endif
-
-       return (void*) vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
-       unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-       int type;
-
-       if (vaddr < FIXADDR_START)
-               return;
-
-       type = kmap_atomic_idx();
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-       {
-               unsigned long idx;
-
-               idx = type + KM_TYPE_NR * smp_processor_id();
-               BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN+idx));
-
-               /* XXX Fix - Anton */
-#if 0
-               __flush_cache_one(vaddr);
-#else
-               flush_cache_all();
-#endif
-
-               /*
-                * force other mappings to Oops if they'll try to access
-                * this pte without first remap it
-                */
-               pte_clear(&init_mm, vaddr, kmap_pte-idx);
-               /* XXX Fix - Anton */
-#if 0
-               __flush_tlb_one(vaddr);
-#else
-               flush_tlb_all();
-#endif
-       }
-#endif
-
-       kmap_atomic_idx_pop();
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
index 0070f8b..a03caa5 100644 (file)
@@ -971,8 +971,6 @@ void __init srmmu_paging_init(void)
 
        sparc_context_init(num_contexts);
 
-       kmap_init();
-
        {
                unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0 };
 
index 2c697a1..2efac58 100644 (file)
@@ -3,7 +3,6 @@
 #define __UM_FIXMAP_H
 
 #include <asm/processor.h>
-#include <asm/kmap_types.h>
 #include <asm/archparam.h>
 #include <asm/page.h>
 #include <linux/threads.h>
index b426796..52e2c36 100644 (file)
@@ -2,22 +2,7 @@
 #ifndef __ASM_UM_HARDIRQ_H
 #define __ASM_UM_HARDIRQ_H
 
-#include <linux/cache.h>
-#include <linux/threads.h>
-
-typedef struct {
-       unsigned int __softirq_pending;
-} ____cacheline_aligned irq_cpustat_t;
-
-#include <linux/irq_cpustat.h> /* Standard mappings for irq_cpustat_t above */
-#include <linux/irq.h>
-
-#ifndef ack_bad_irq
-static inline void ack_bad_irq(unsigned int irq)
-{
-       printk(KERN_CRIT "unexpected IRQ trap at vector %02x\n", irq);
-}
-#endif
+#include <asm-generic/hardirq.h>
 
 #define __ARCH_IRQ_EXIT_IRQS_DISABLED 1
 
diff --git a/arch/um/include/asm/kmap_types.h b/arch/um/include/asm/kmap_types.h
deleted file mode 100644 (file)
index b0bd12d..0000000
+++ /dev/null
@@ -1,13 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-/* 
- * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
- */
-
-#ifndef __UM_KMAP_TYPES_H
-#define __UM_KMAP_TYPES_H
-
-/* No more #include "asm/arch/kmap_types.h" ! */
-
-#define KM_TYPE_NR 14
-
-#endif
index e4abac6..1739994 100644 (file)
@@ -1,15 +1,19 @@
 // SPDX-License-Identifier: GPL-2.0
 #include <linux/kmsg_dump.h>
+#include <linux/spinlock.h>
 #include <linux/console.h>
 #include <shared/init.h>
 #include <shared/kern.h>
 #include <os.h>
 
 static void kmsg_dumper_stdout(struct kmsg_dumper *dumper,
-                               enum kmsg_dump_reason reason)
+                               enum kmsg_dump_reason reason,
+                               struct kmsg_dumper_iter *iter)
 {
+       static DEFINE_SPINLOCK(lock);
        static char line[1024];
        struct console *con;
+       unsigned long flags;
        size_t len = 0;
 
        /* only dump kmsg when no console is available */
@@ -24,11 +28,16 @@ static void kmsg_dumper_stdout(struct kmsg_dumper *dumper,
        if (con)
                return;
 
+       if (!spin_trylock_irqsave(&lock, flags))
+               return;
+
        printf("kmsg_dump:\n");
-       while (kmsg_dump_get_line(dumper, true, line, sizeof(line), &len)) {
+       while (kmsg_dump_get_line(iter, true, line, sizeof(line), &len)) {
                line[len] = '\0';
                printf("%s", line);
        }
+
+       spin_unlock_irqrestore(&lock, flags);
 }
 
 static struct kmsg_dumper kmsg_dumper = {
index fb873a7..38583e9 100644 (file)
@@ -15,6 +15,7 @@ config X86_32
        select CLKSRC_I8253
        select CLONE_BACKWARDS
        select HAVE_DEBUG_STACKOVERFLOW
+       select KMAP_LOCAL
        select MODULES_USE_ELF_REL
        select OLD_SIGACTION
        select GENERIC_VDSO_32
@@ -93,6 +94,7 @@ config X86
        select ARCH_SUPPORTS_ACPI
        select ARCH_SUPPORTS_ATOMIC_RMW
        select ARCH_SUPPORTS_NUMA_BALANCING     if X86_64
+       select ARCH_SUPPORTS_RT
        select ARCH_USE_BUILTIN_BSWAP
        select ARCH_USE_QUEUED_RWLOCKS
        select ARCH_USE_QUEUED_SPINLOCKS
@@ -210,6 +212,7 @@ config X86
        select HAVE_PCI
        select HAVE_PERF_REGS
        select HAVE_PERF_USER_STACK_DUMP
+       select HAVE_PREEMPT_LAZY
        select MMU_GATHER_RCU_TABLE_FREE                if PARAVIRT
        select HAVE_POSIX_CPU_TIMERS_TASK_WORK
        select HAVE_REGS_AND_STACK_ACCESS_API
index be891fd..29c716e 100644 (file)
@@ -379,14 +379,14 @@ static int ecb_encrypt(struct skcipher_request *req)
 
        err = skcipher_walk_virt(&walk, req, true);
 
-       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);
+               kernel_fpu_end();
                nbytes &= AES_BLOCK_SIZE - 1;
                err = skcipher_walk_done(&walk, nbytes);
        }
-       kernel_fpu_end();
 
        return err;
 }
@@ -401,14 +401,14 @@ static int ecb_decrypt(struct skcipher_request *req)
 
        err = skcipher_walk_virt(&walk, req, true);
 
-       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 = skcipher_walk_done(&walk, nbytes);
        }
-       kernel_fpu_end();
 
        return err;
 }
@@ -423,14 +423,14 @@ static int cbc_encrypt(struct skcipher_request *req)
 
        err = skcipher_walk_virt(&walk, req, true);
 
-       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 = skcipher_walk_done(&walk, nbytes);
        }
-       kernel_fpu_end();
 
        return err;
 }
@@ -445,14 +445,14 @@ static int cbc_decrypt(struct skcipher_request *req)
 
        err = skcipher_walk_virt(&walk, req, true);
 
-       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 = skcipher_walk_done(&walk, nbytes);
        }
-       kernel_fpu_end();
 
        return err;
 }
@@ -500,18 +500,20 @@ static int ctr_crypt(struct skcipher_request *req)
 
        err = skcipher_walk_virt(&walk, req, true);
 
-       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 = skcipher_walk_done(&walk, nbytes);
        }
        if (walk.nbytes) {
+               kernel_fpu_begin();
                ctr_crypt_final(ctx, &walk);
+               kernel_fpu_end();
                err = skcipher_walk_done(&walk, 0);
        }
-       kernel_fpu_end();
 
        return err;
 }
index 384ccb0..2f8df8e 100644 (file)
@@ -46,7 +46,7 @@ static inline void cast5_fpu_end(bool fpu_enabled)
 
 static int ecb_crypt(struct skcipher_request *req, bool enc)
 {
-       bool fpu_enabled = false;
+       bool fpu_enabled;
        struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
        struct cast5_ctx *ctx = crypto_skcipher_ctx(tfm);
        struct skcipher_walk walk;
@@ -61,7 +61,7 @@ static int ecb_crypt(struct skcipher_request *req, bool enc)
                u8 *wsrc = walk.src.virt.addr;
                u8 *wdst = walk.dst.virt.addr;
 
-               fpu_enabled = cast5_fpu_begin(fpu_enabled, &walk, nbytes);
+               fpu_enabled = cast5_fpu_begin(false, &walk, nbytes);
 
                /* Process multi-block batch */
                if (nbytes >= bsize * CAST5_PARALLEL_BLOCKS) {
@@ -90,10 +90,9 @@ static int ecb_crypt(struct skcipher_request *req, bool enc)
                } while (nbytes >= bsize);
 
 done:
+               cast5_fpu_end(fpu_enabled);
                err = skcipher_walk_done(&walk, nbytes);
        }
-
-       cast5_fpu_end(fpu_enabled);
        return err;
 }
 
@@ -197,7 +196,7 @@ static int cbc_decrypt(struct skcipher_request *req)
 {
        struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
        struct cast5_ctx *ctx = crypto_skcipher_ctx(tfm);
-       bool fpu_enabled = false;
+       bool fpu_enabled;
        struct skcipher_walk walk;
        unsigned int nbytes;
        int err;
@@ -205,12 +204,11 @@ static int cbc_decrypt(struct skcipher_request *req)
        err = skcipher_walk_virt(&walk, req, false);
 
        while ((nbytes = walk.nbytes)) {
-               fpu_enabled = cast5_fpu_begin(fpu_enabled, &walk, nbytes);
+               fpu_enabled = cast5_fpu_begin(false, &walk, nbytes);
                nbytes = __cbc_decrypt(ctx, &walk);
+               cast5_fpu_end(fpu_enabled);
                err = skcipher_walk_done(&walk, nbytes);
        }
-
-       cast5_fpu_end(fpu_enabled);
        return err;
 }
 
@@ -277,7 +275,7 @@ static int ctr_crypt(struct skcipher_request *req)
 {
        struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
        struct cast5_ctx *ctx = crypto_skcipher_ctx(tfm);
-       bool fpu_enabled = false;
+       bool fpu_enabled;
        struct skcipher_walk walk;
        unsigned int nbytes;
        int err;
@@ -285,13 +283,12 @@ static int ctr_crypt(struct skcipher_request *req)
        err = skcipher_walk_virt(&walk, req, false);
 
        while ((nbytes = walk.nbytes) >= CAST5_BLOCK_SIZE) {
-               fpu_enabled = cast5_fpu_begin(fpu_enabled, &walk, nbytes);
+               fpu_enabled = cast5_fpu_begin(false, &walk, nbytes);
                nbytes = __ctr_crypt(&walk, ctx);
+               cast5_fpu_end(fpu_enabled);
                err = skcipher_walk_done(&walk, nbytes);
        }
 
-       cast5_fpu_end(fpu_enabled);
-
        if (walk.nbytes) {
                ctr_crypt_final(&walk, ctx);
                err = skcipher_walk_done(&walk, 0);
index d3d91a0..6d07747 100644 (file)
@@ -24,7 +24,7 @@ int glue_ecb_req_128bit(const struct common_glue_ctx *gctx,
        void *ctx = crypto_skcipher_ctx(crypto_skcipher_reqtfm(req));
        const unsigned int bsize = 128 / 8;
        struct skcipher_walk walk;
-       bool fpu_enabled = false;
+       bool fpu_enabled;
        unsigned int nbytes;
        int err;
 
@@ -37,7 +37,7 @@ int glue_ecb_req_128bit(const struct common_glue_ctx *gctx,
                unsigned int i;
 
                fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
-                                            &walk, fpu_enabled, nbytes);
+                                            &walk, false, nbytes);
                for (i = 0; i < gctx->num_funcs; i++) {
                        func_bytes = bsize * gctx->funcs[i].num_blocks;
 
@@ -55,10 +55,9 @@ int glue_ecb_req_128bit(const struct common_glue_ctx *gctx,
                        if (nbytes < bsize)
                                break;
                }
+               glue_fpu_end(fpu_enabled);
                err = skcipher_walk_done(&walk, nbytes);
        }
-
-       glue_fpu_end(fpu_enabled);
        return err;
 }
 EXPORT_SYMBOL_GPL(glue_ecb_req_128bit);
@@ -101,7 +100,7 @@ int glue_cbc_decrypt_req_128bit(const struct common_glue_ctx *gctx,
        void *ctx = crypto_skcipher_ctx(crypto_skcipher_reqtfm(req));
        const unsigned int bsize = 128 / 8;
        struct skcipher_walk walk;
-       bool fpu_enabled = false;
+       bool fpu_enabled;
        unsigned int nbytes;
        int err;
 
@@ -115,7 +114,7 @@ int glue_cbc_decrypt_req_128bit(const struct common_glue_ctx *gctx,
                u128 last_iv;
 
                fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
-                                            &walk, fpu_enabled, nbytes);
+                                            &walk, false, nbytes);
                /* Start of the last block. */
                src += nbytes / bsize - 1;
                dst += nbytes / bsize - 1;
@@ -148,10 +147,10 @@ int glue_cbc_decrypt_req_128bit(const struct common_glue_ctx *gctx,
 done:
                u128_xor(dst, dst, (u128 *)walk.iv);
                *(u128 *)walk.iv = last_iv;
+               glue_fpu_end(fpu_enabled);
                err = skcipher_walk_done(&walk, nbytes);
        }
 
-       glue_fpu_end(fpu_enabled);
        return err;
 }
 EXPORT_SYMBOL_GPL(glue_cbc_decrypt_req_128bit);
@@ -162,7 +161,7 @@ int glue_ctr_req_128bit(const struct common_glue_ctx *gctx,
        void *ctx = crypto_skcipher_ctx(crypto_skcipher_reqtfm(req));
        const unsigned int bsize = 128 / 8;
        struct skcipher_walk walk;
-       bool fpu_enabled = false;
+       bool fpu_enabled;
        unsigned int nbytes;
        int err;
 
@@ -176,7 +175,7 @@ int glue_ctr_req_128bit(const struct common_glue_ctx *gctx,
                le128 ctrblk;
 
                fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
-                                            &walk, fpu_enabled, nbytes);
+                                            &walk, false, nbytes);
 
                be128_to_le128(&ctrblk, (be128 *)walk.iv);
 
@@ -202,11 +201,10 @@ int glue_ctr_req_128bit(const struct common_glue_ctx *gctx,
                }
 
                le128_to_be128((be128 *)walk.iv, &ctrblk);
+               glue_fpu_end(fpu_enabled);
                err = skcipher_walk_done(&walk, nbytes);
        }
 
-       glue_fpu_end(fpu_enabled);
-
        if (nbytes) {
                le128 ctrblk;
                u128 tmp;
@@ -306,8 +304,14 @@ int glue_xts_req_128bit(const struct common_glue_ctx *gctx,
        tweak_fn(tweak_ctx, walk.iv, walk.iv);
 
        while (nbytes) {
+               fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
+                                            &walk, fpu_enabled,
+                                            nbytes < bsize ? bsize : nbytes);
                nbytes = __glue_xts_req_128bit(gctx, crypt_ctx, &walk);
 
+               glue_fpu_end(fpu_enabled);
+               fpu_enabled = false;
+
                err = skcipher_walk_done(&walk, nbytes);
                nbytes = walk.nbytes;
        }
index 77217bd..8eba66a 100644 (file)
@@ -31,7 +31,7 @@
 #include <asm/pgtable_types.h>
 #ifdef CONFIG_X86_32
 #include <linux/threads.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 #else
 #include <uapi/asm/vsyscall.h>
 #endif
@@ -94,7 +94,7 @@ enum fixed_addresses {
 #endif
 #ifdef CONFIG_X86_32
        FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
-       FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
+       FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
 #ifdef CONFIG_PCI_MMCONFIG
        FIX_PCIE_MCFG,
 #endif
@@ -151,7 +151,6 @@ extern void reserve_top_address(unsigned long reserve);
 
 extern int fixmaps_set;
 
-extern pte_t *kmap_pte;
 extern pte_t *pkmap_page_table;
 
 void __native_set_fixmap(enum fixed_addresses idx, pte_t pte);
index 8b9bfaa..d31b088 100644 (file)
@@ -28,6 +28,7 @@ extern void kernel_fpu_begin_mask(unsigned int kfpu_mask);
 extern void kernel_fpu_end(void);
 extern bool irq_fpu_usable(void);
 extern void fpregs_mark_activate(void);
+extern void kernel_fpu_resched(void);
 
 /* Code that is unaware of kernel_fpu_begin_mask() can use this */
 static inline void kernel_fpu_begin(void)
@@ -40,17 +41,32 @@ static inline void kernel_fpu_begin(void)
  * A context switch will (and softirq might) save CPU's FPU registers to
  * fpu->state and set TIF_NEED_FPU_LOAD leaving CPU's FPU registers in
  * a random state.
+ *
+ * local_bh_disable() protects against both preemption and soft interrupts
+ * on !RT kernels.
+ *
+ * On RT kernels local_bh_disable() is not sufficient because it only
+ * serializes soft interrupt related sections via a local lock, but stays
+ * preemptible. Disabling preemption is the right choice here as bottom
+ * half processing is always in thread context on RT kernels so it
+ * implicitly prevents bottom half processing as well.
+ *
+ * Disabling preemption also serializes against kernel_fpu_begin().
  */
 static inline void fpregs_lock(void)
 {
-       preempt_disable();
-       local_bh_disable();
+       if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+               local_bh_disable();
+       else
+               preempt_disable();
 }
 
 static inline void fpregs_unlock(void)
 {
-       local_bh_enable();
-       preempt_enable();
+       if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+               local_bh_enable();
+       else
+               preempt_enable();
 }
 
 #ifdef CONFIG_X86_DEBUG_FPU
index 0f420b2..032e020 100644 (file)
@@ -23,7 +23,6 @@
 
 #include <linux/interrupt.h>
 #include <linux/threads.h>
-#include <asm/kmap_types.h>
 #include <asm/tlbflush.h>
 #include <asm/paravirt.h>
 #include <asm/fixmap.h>
@@ -58,11 +57,17 @@ extern unsigned long highstart_pfn, highend_pfn;
 #define PKMAP_NR(virt)  ((virt-PKMAP_BASE) >> PAGE_SHIFT)
 #define PKMAP_ADDR(nr)  (PKMAP_BASE + ((nr) << PAGE_SHIFT))
 
-void *kmap_atomic_pfn(unsigned long pfn);
-void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot);
-
 #define flush_cache_kmaps()    do { } while (0)
 
+#define        arch_kmap_local_post_map(vaddr, pteval)         \
+       arch_flush_lazy_mmu_mode()
+
+#define        arch_kmap_local_post_unmap(vaddr)               \
+       do {                                            \
+               flush_tlb_one_kernel((vaddr));          \
+               arch_flush_lazy_mmu_mode();             \
+       } while (0)
+
 extern void add_highpages_with_active_regions(int nid, unsigned long start_pfn,
                                        unsigned long end_pfn);
 
index bacf68c..e2de092 100644 (file)
@@ -9,19 +9,14 @@
 #include <linux/fs.h>
 #include <linux/mm.h>
 #include <linux/uaccess.h>
+#include <linux/highmem.h>
 #include <asm/cacheflush.h>
 #include <asm/tlbflush.h>
 
-void __iomem *
-iomap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot);
+void __iomem *__iomap_local_pfn_prot(unsigned long pfn, pgprot_t prot);
 
-void
-iounmap_atomic(void __iomem *kvaddr);
+int iomap_create_wc(resource_size_t base, unsigned long size, pgprot_t *prot);
 
-int
-iomap_create_wc(resource_size_t base, unsigned long size, pgprot_t *prot);
-
-void
-iomap_free(resource_size_t base, unsigned long size);
+void iomap_free(resource_size_t base, unsigned long size);
 
 #endif /* _ASM_X86_IOMAP_H */
diff --git a/arch/x86/include/asm/kmap_types.h b/arch/x86/include/asm/kmap_types.h
deleted file mode 100644 (file)
index 04ab826..0000000
+++ /dev/null
@@ -1,13 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_X86_KMAP_TYPES_H
-#define _ASM_X86_KMAP_TYPES_H
-
-#if defined(CONFIG_X86_32) && defined(CONFIG_DEBUG_HIGHMEM)
-#define  __WITH_KM_FENCE
-#endif
-
-#include <asm-generic/kmap_types.h>
-
-#undef __WITH_KM_FENCE
-
-#endif /* _ASM_X86_KMAP_TYPES_H */
index 903d718..130f428 100644 (file)
@@ -41,7 +41,6 @@
 #ifndef __ASSEMBLY__
 
 #include <asm/desc_defs.h>
-#include <asm/kmap_types.h>
 #include <asm/pgtable_types.h>
 #include <asm/nospec-branch.h>
 
index a334dd0..afe37a8 100644 (file)
@@ -89,20 +89,54 @@ 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)
 {
        return GEN_UNARY_RMWcc("decl", __preempt_count, e, __percpu_arg([var]));
 }
 
+static __always_inline bool __preempt_count_dec_and_test(void)
+{
+       if (____preempt_count_dec_and_test())
+               return true;
+#ifdef CONFIG_PREEMPT_LAZY
+       if (preempt_count())
+               return false;
+       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 != preempt_offset)
+               return false;
+       /* XXX PREEMPT_LOCK_OFFSET */
+       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_PREEMPTION
+#ifdef CONFIG_PREEMPT_RT
+  extern void preempt_schedule_lock(void);
+#endif
   extern asmlinkage void preempt_schedule_thunk(void);
 # define __preempt_schedule() \
        asm volatile ("call preempt_schedule_thunk" : ASM_CALL_CONSTRAINT)
index 6fd8410..f3bf2f5 100644 (file)
@@ -28,6 +28,19 @@ 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 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)
+#define ARCH_RT_DELAYS_SIGNAL_SEND
+#endif
+
 #ifndef CONFIG_COMPAT
 typedef sigset_t compat_sigset_t;
 #endif
index 7fb482f..3df0a95 100644 (file)
@@ -65,7 +65,7 @@
  */
 static __always_inline void boot_init_stack_canary(void)
 {
-       u64 canary;
+       u64 canary = 0;
        u64 tsc;
 
 #ifdef CONFIG_X86_64
@@ -76,8 +76,14 @@ 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
        get_random_bytes(&canary, sizeof(canary));
+#endif
        tsc = rdtsc();
        canary += tsc + (tsc << 32UL);
        canary &= CANARY_MASK;
index e701f29..596a46c 100644 (file)
@@ -56,17 +56,24 @@ struct task_struct;
 struct thread_info {
        unsigned long           flags;          /* low level flags */
        u32                     status;         /* thread synchronous flags */
+       int                     preempt_lazy_count;     /* 0 => lazy preemptable
+                                                         <0 => BUG */
 };
 
 #define INIT_THREAD_INFO(tsk)                  \
 {                                              \
        .flags          = 0,                    \
+       .preempt_lazy_count = 0,                \
 }
 
 #else /* !__ASSEMBLY__ */
 
 #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_NOTSC              16      /* TSC is not accessible in userland */
 #define TIF_IA32               17      /* IA32 compatibility process */
 #define TIF_SLD                        18      /* Restore split lock detection on context switch */
+#define TIF_NEED_RESCHED_LAZY  19      /* lazy rescheduling necessary */
 #define TIF_MEMDIE             20      /* is terminating due to OOM killer */
 #define TIF_POLLING_NRFLAG     21      /* idle is polling for TIF_NEED_RESCHED */
 #define TIF_IO_BITMAP          22      /* uses I/O bitmap */
@@ -122,6 +130,7 @@ struct thread_info {
 #define _TIF_NOTSC             (1 << TIF_NOTSC)
 #define _TIF_IA32              (1 << TIF_IA32)
 #define _TIF_SLD               (1 << TIF_SLD)
+#define _TIF_NEED_RESCHED_LAZY (1 << TIF_NEED_RESCHED_LAZY)
 #define _TIF_POLLING_NRFLAG    (1 << TIF_POLLING_NRFLAG)
 #define _TIF_IO_BITMAP         (1 << TIF_IO_BITMAP)
 #define _TIF_FORCED_TF         (1 << TIF_FORCED_TF)
@@ -154,6 +163,8 @@ struct thread_info {
 
 #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 65d1171..1809816 100644 (file)
@@ -80,11 +80,12 @@ EXPORT_SYMBOL_GPL(hv_remove_vmbus_irq);
 DEFINE_IDTENTRY_SYSVEC(sysvec_hyperv_stimer0)
 {
        struct pt_regs *old_regs = set_irq_regs(regs);
+       u64 ip = regs ? instruction_pointer(regs) : 0;
 
        inc_irq_stat(hyperv_stimer0_count);
        if (hv_stimer0_handler)
                hv_stimer0_handler();
-       add_interrupt_randomness(HYPERV_STIMER0_VECTOR, 0);
+       add_interrupt_randomness(HYPERV_STIMER0_VECTOR, 0, ip);
        ack_APIC_irq();
 
        set_irq_regs(old_regs);
index 33ee476..5fcac46 100644 (file)
@@ -13,8 +13,6 @@
 
 #include <linux/uaccess.h>
 
-static void *kdump_buf_page;
-
 static inline bool is_crashed_pfn_valid(unsigned long pfn)
 {
 #ifndef CONFIG_X86_PAE
@@ -41,15 +39,11 @@ static inline bool is_crashed_pfn_valid(unsigned long pfn)
  * @userbuf: if set, @buf is in user address space, use copy_to_user(),
  *     otherwise @buf is in kernel address space, use memcpy().
  *
- * Copy a page from "oldmem". For this page, there is no pte mapped
- * in the current kernel. We stitch up a pte, similar to kmap_atomic.
- *
- * Calling copy_to_user() in atomic context is not desirable. Hence first
- * copying the data to a pre-allocated kernel page and then copying to user
- * space in non-atomic context.
+ * Copy a page from "oldmem". For this page, there might be no pte mapped
+ * in the current kernel.
  */
-ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
-                               size_t csize, unsigned long offset, int userbuf)
+ssize_t copy_oldmem_page(unsigned long pfn, char *buf, size_t csize,
+                        unsigned long offset, int userbuf)
 {
        void  *vaddr;
 
@@ -59,38 +53,16 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
        if (!is_crashed_pfn_valid(pfn))
                return -EFAULT;
 
-       vaddr = kmap_atomic_pfn(pfn);
+       vaddr = kmap_local_pfn(pfn);
 
        if (!userbuf) {
-               memcpy(buf, (vaddr + offset), csize);
-               kunmap_atomic(vaddr);
+               memcpy(buf, vaddr + offset, csize);
        } else {
-               if (!kdump_buf_page) {
-                       printk(KERN_WARNING "Kdump: Kdump buffer page not"
-                               " allocated\n");
-                       kunmap_atomic(vaddr);
-                       return -EFAULT;
-               }
-               copy_page(kdump_buf_page, vaddr);
-               kunmap_atomic(vaddr);
-               if (copy_to_user(buf, (kdump_buf_page + offset), csize))
-                       return -EFAULT;
+               if (copy_to_user(buf, vaddr + offset, csize))
+                       csize = -EFAULT;
        }
 
-       return csize;
-}
+       kunmap_local(vaddr);
 
-static int __init kdump_buf_page_init(void)
-{
-       int ret = 0;
-
-       kdump_buf_page = kmalloc(PAGE_SIZE, GFP_KERNEL);
-       if (!kdump_buf_page) {
-               printk(KERN_WARNING "Kdump: Failed to allocate kdump buffer"
-                        " page\n");
-               ret = -ENOMEM;
-       }
-
-       return ret;
+       return csize;
 }
-arch_initcall(kdump_buf_page_init);
index 571220a..d315d45 100644 (file)
@@ -159,6 +159,18 @@ 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);
+
 /*
  * Save the FPU state (mark it for reload if necessary):
  *
index 0b79efc..93c6b88 100644 (file)
@@ -131,6 +131,7 @@ int irq_init_percpu_irqstack(unsigned int cpu)
        return 0;
 }
 
+#ifndef CONFIG_PREEMPT_RT
 void do_softirq_own_stack(void)
 {
        struct irq_stack *irqstk;
@@ -147,6 +148,7 @@ void do_softirq_own_stack(void)
 
        call_on_stack(__do_softirq, isp);
 }
+#endif
 
 void __handle_irq(struct irq_desc *desc, struct pt_regs *regs)
 {
index 440eed5..7cfc4e6 100644 (file)
@@ -72,7 +72,9 @@ int irq_init_percpu_irqstack(unsigned int cpu)
        return map_irq_stack(cpu);
 }
 
+#ifndef CONFIG_PREEMPT_RT
 void do_softirq_own_stack(void)
 {
        run_on_irqstack_cond(__do_softirq, NULL);
 }
+#endif
index 271669d..f61a0d7 100644 (file)
@@ -7975,6 +7975,14 @@ int kvm_arch_init(void *opaque)
                goto out;
        }
 
+#ifdef CONFIG_PREEMPT_RT
+       if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) {
+               pr_err("RT requires X86_FEATURE_CONSTANT_TSC\n");
+               r = -EOPNOTSUPP;
+               goto out;
+       }
+#endif
+
        r = -ENOMEM;
        x86_fpu_cache = kmem_cache_create("x86_fpu", sizeof(struct fpu),
                                          __alignof__(struct fpu), SLAB_ACCOUNT,
index 075fe51..2c54b76 100644 (file)
@@ -4,65 +4,6 @@
 #include <linux/swap.h> /* for totalram_pages */
 #include <linux/memblock.h>
 
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
-       unsigned long vaddr;
-       int idx, type;
-
-       type = kmap_atomic_idx_push();
-       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));
-       arch_flush_lazy_mmu_mode();
-
-       return (void *)vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-/*
- * This is the same as kmap_atomic() but can map memory that doesn't
- * have a struct page associated with it.
- */
-void *kmap_atomic_pfn(unsigned long pfn)
-{
-       return kmap_atomic_prot_pfn(pfn, kmap_prot);
-}
-EXPORT_SYMBOL_GPL(kmap_atomic_pfn);
-
-void kunmap_atomic_high(void *kvaddr)
-{
-       unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-
-       if (vaddr >= __fix_to_virt(FIX_KMAP_END) &&
-           vaddr <= __fix_to_virt(FIX_KMAP_BEGIN)) {
-               int idx, type;
-
-               type = kmap_atomic_idx();
-               idx = type + KM_TYPE_NR * smp_processor_id();
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-               WARN_ON_ONCE(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
-#endif
-               /*
-                * Force other mappings to Oops if they'll try to access this
-                * pte without first remap it.  Keeping stale mappings around
-                * is a bad idea also, in case the page changes cacheability
-                * attributes or becomes a protected page in a hypervisor.
-                */
-               kpte_clear_flush(kmap_pte-idx, vaddr);
-               kmap_atomic_idx_pop();
-               arch_flush_lazy_mmu_mode();
-       }
-#ifdef CONFIG_DEBUG_HIGHMEM
-       else {
-               BUG_ON(vaddr < PAGE_OFFSET);
-               BUG_ON(vaddr >= (unsigned long)high_memory);
-       }
-#endif
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
-
 void __init set_highmem_pages_init(void)
 {
        struct zone *zone;
index 7c05525..da31c26 100644 (file)
@@ -394,19 +394,6 @@ repeat:
        return last_map_addr;
 }
 
-pte_t *kmap_pte;
-
-static void __init kmap_init(void)
-{
-       unsigned long kmap_vstart;
-
-       /*
-        * Cache the first kmap pte:
-        */
-       kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
-       kmap_pte = virt_to_kpte(kmap_vstart);
-}
-
 #ifdef CONFIG_HIGHMEM
 static void __init permanent_kmaps_init(pgd_t *pgd_base)
 {
@@ -712,8 +699,6 @@ void __init paging_init(void)
 
        __flush_tlb_all();
 
-       kmap_init();
-
        /*
         * NOTE: at this point the bootmem allocator is fully available.
         */
index f60398a..9aaa756 100644 (file)
@@ -44,28 +44,7 @@ void iomap_free(resource_size_t base, unsigned long size)
 }
 EXPORT_SYMBOL_GPL(iomap_free);
 
-void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot)
-{
-       unsigned long vaddr;
-       int idx, type;
-
-       preempt_disable();
-       pagefault_disable();
-
-       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));
-       arch_flush_lazy_mmu_mode();
-
-       return (void *)vaddr;
-}
-
-/*
- * Map 'pfn' using protections 'prot'
- */
-void __iomem *
-iomap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot)
+void __iomem *__iomap_local_pfn_prot(unsigned long pfn, pgprot_t prot)
 {
        /*
         * For non-PAT systems, translate non-WB request to UC- just in
@@ -81,36 +60,6 @@ iomap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot)
        /* Filter out unsupported __PAGE_KERNEL* bits: */
        pgprot_val(prot) &= __default_kernel_pte_mask;
 
-       return (void __force __iomem *) kmap_atomic_prot_pfn(pfn, prot);
-}
-EXPORT_SYMBOL_GPL(iomap_atomic_prot_pfn);
-
-void
-iounmap_atomic(void __iomem *kvaddr)
-{
-       unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-
-       if (vaddr >= __fix_to_virt(FIX_KMAP_END) &&
-           vaddr <= __fix_to_virt(FIX_KMAP_BEGIN)) {
-               int idx, type;
-
-               type = kmap_atomic_idx();
-               idx = type + KM_TYPE_NR * smp_processor_id();
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-               WARN_ON_ONCE(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
-#endif
-               /*
-                * Force other mappings to Oops if they'll try to access this
-                * pte without first remap it.  Keeping stale mappings around
-                * is a bad idea also, in case the page changes cacheability
-                * attributes or becomes a protected page in a hypervisor.
-                */
-               kpte_clear_flush(kmap_pte-idx, vaddr);
-               kmap_atomic_idx_pop();
-       }
-
-       pagefault_enable();
-       preempt_enable();
+       return (void __force __iomem *)__kmap_local_pfn_prot(pfn, prot);
 }
-EXPORT_SYMBOL_GPL(iounmap_atomic);
+EXPORT_SYMBOL_GPL(__iomap_local_pfn_prot);
index 87e08ad..03cbf6b 100644 (file)
@@ -666,6 +666,7 @@ endchoice
 config HIGHMEM
        bool "High Memory Support"
        depends on MMU
+       select KMAP_LOCAL
        help
          Linux can use the full amount of RAM in the system by
          default. However, the default MMUv2 setup only maps the
index a06ffb0..92049b6 100644 (file)
@@ -16,7 +16,7 @@
 #ifdef CONFIG_HIGHMEM
 #include <linux/threads.h>
 #include <linux/pgtable.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 #endif
 
 /*
@@ -39,7 +39,7 @@ enum fixed_addresses {
        /* reserved pte's for temporary kernel mappings */
        FIX_KMAP_BEGIN,
        FIX_KMAP_END = FIX_KMAP_BEGIN +
-               (KM_TYPE_NR * NR_CPUS * DCACHE_N_COLORS) - 1,
+               (KM_MAX_IDX * NR_CPUS * DCACHE_N_COLORS) - 1,
 #endif
        __end_of_fixed_addresses
 };
index eac5032..0fc3b1c 100644 (file)
@@ -16,9 +16,8 @@
 #include <linux/pgtable.h>
 #include <asm/cacheflush.h>
 #include <asm/fixmap.h>
-#include <asm/kmap_types.h>
 
-#define PKMAP_BASE             ((FIXADDR_START - \
+#define PKMAP_BASE             ((FIXADDR_START -                       \
                                  (LAST_PKMAP + 1) * PAGE_SIZE) & PMD_MASK)
 #define LAST_PKMAP             (PTRS_PER_PTE * DCACHE_N_COLORS)
 #define LAST_PKMAP_MASK                (LAST_PKMAP - 1)
@@ -68,6 +67,15 @@ static inline void flush_cache_kmaps(void)
        flush_cache_all();
 }
 
+enum fixed_addresses kmap_local_map_idx(int type, unsigned long pfn);
+#define arch_kmap_local_map_idx                kmap_local_map_idx
+
+enum fixed_addresses kmap_local_unmap_idx(int type, unsigned long addr);
+#define arch_kmap_local_unmap_idx      kmap_local_unmap_idx
+
+#define arch_kmap_local_post_unmap(vaddr)      \
+       local_flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE)
+
 void kmap_init(void);
 
 #endif
index 64c9389..dc84632 100644 (file)
@@ -2,10 +2,6 @@
 #ifndef __ASM_SPINLOCK_TYPES_H
 #define __ASM_SPINLOCK_TYPES_H
 
-#if !defined(__LINUX_SPINLOCK_TYPES_H) && !defined(__ASM_SPINLOCK_H)
-# error "please don't include this file directly"
-#endif
-
 #include <asm-generic/qspinlock_types.h>
 #include <asm-generic/qrwlock_types.h>
 
index 673196f..0735ca5 100644 (file)
@@ -12,8 +12,6 @@
 #include <linux/highmem.h>
 #include <asm/tlbflush.h>
 
-static pte_t *kmap_pte;
-
 #if DCACHE_WAY_SIZE > PAGE_SIZE
 unsigned int last_pkmap_nr_arr[DCACHE_N_COLORS];
 wait_queue_head_t pkmap_map_wait_arr[DCACHE_N_COLORS];
@@ -33,59 +31,25 @@ static inline void kmap_waitqueues_init(void)
 
 static inline enum fixed_addresses kmap_idx(int type, unsigned long color)
 {
-       return (type + KM_TYPE_NR * smp_processor_id()) * DCACHE_N_COLORS +
+       return (type + KM_MAX_IDX * smp_processor_id()) * DCACHE_N_COLORS +
                color;
 }
 
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
+enum fixed_addresses kmap_local_map_idx(int type, unsigned long pfn)
 {
-       enum fixed_addresses idx;
-       unsigned long vaddr;
-
-       idx = kmap_idx(kmap_atomic_idx_push(),
-                      DCACHE_ALIAS(page_to_phys(page)));
-       vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-#ifdef CONFIG_DEBUG_HIGHMEM
-       BUG_ON(!pte_none(*(kmap_pte + idx)));
-#endif
-       set_pte(kmap_pte + idx, mk_pte(page, prot));
-
-       return (void *)vaddr;
+       return kmap_idx(type, DCACHE_ALIAS(pfn << PAGE_SHIFT));
 }
-EXPORT_SYMBOL(kmap_atomic_high_prot);
 
-void kunmap_atomic_high(void *kvaddr)
+enum fixed_addresses kmap_local_unmap_idx(int type, unsigned long addr)
 {
-       if (kvaddr >= (void *)FIXADDR_START &&
-           kvaddr < (void *)FIXADDR_TOP) {
-               int idx = kmap_idx(kmap_atomic_idx(),
-                                  DCACHE_ALIAS((unsigned long)kvaddr));
-
-               /*
-                * Force other mappings to Oops if they'll try to access this
-                * pte without first remap it.  Keeping stale mappings around
-                * is a bad idea also, in case the page changes cacheability
-                * attributes or becomes a protected page in a hypervisor.
-                */
-               pte_clear(&init_mm, kvaddr, kmap_pte + idx);
-               local_flush_tlb_kernel_range((unsigned long)kvaddr,
-                                            (unsigned long)kvaddr + PAGE_SIZE);
-
-               kmap_atomic_idx_pop();
-       }
+       return kmap_idx(type, DCACHE_ALIAS(addr));
 }
-EXPORT_SYMBOL(kunmap_atomic_high);
 
 void __init kmap_init(void)
 {
-       unsigned long kmap_vstart;
-
        /* Check if this memory layout is broken because PKMAP overlaps
         * page table.
         */
        BUILD_BUG_ON(PKMAP_BASE < TLBTEMP_BASE_1 + TLBTEMP_SIZE);
-       /* cache the first kmap pte */
-       kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
-       kmap_pte = virt_to_kpte(kmap_vstart);
        kmap_waitqueues_init();
 }
index 15a11a2..ebd6edb 100644 (file)
@@ -41,7 +41,7 @@
 #include "blk-mq-sched.h"
 #include "blk-rq-qos.h"
 
-static DEFINE_PER_CPU(struct list_head, blk_cpu_done);
+static DEFINE_PER_CPU(struct llist_head, blk_cpu_done);
 
 static void blk_mq_poll_stats_start(struct request_queue *q);
 static void blk_mq_poll_stats_fn(struct blk_stat_callback *cb);
@@ -565,80 +565,29 @@ void blk_mq_end_request(struct request *rq, blk_status_t error)
 }
 EXPORT_SYMBOL(blk_mq_end_request);
 
-/*
- * Softirq action handler - move entries to local list and loop over them
- * while passing them to the queue registered handler.
- */
-static __latent_entropy void blk_done_softirq(struct softirq_action *h)
+static void blk_complete_reqs(struct llist_head *list)
 {
-       struct list_head *cpu_list, local_list;
-
-       local_irq_disable();
-       cpu_list = this_cpu_ptr(&blk_cpu_done);
-       list_replace_init(cpu_list, &local_list);
-       local_irq_enable();
-
-       while (!list_empty(&local_list)) {
-               struct request *rq;
+       struct llist_node *entry = llist_reverse_order(llist_del_all(list));
+       struct request *rq, *next;
 
-               rq = list_entry(local_list.next, struct request, ipi_list);
-               list_del_init(&rq->ipi_list);
+       llist_for_each_entry_safe(rq, next, entry, ipi_list)
                rq->q->mq_ops->complete(rq);
-       }
 }
 
-static void blk_mq_trigger_softirq(struct request *rq)
+static __latent_entropy void blk_done_softirq(struct softirq_action *h)
 {
-       struct list_head *list;
-       unsigned long flags;
-
-       local_irq_save(flags);
-       list = this_cpu_ptr(&blk_cpu_done);
-       list_add_tail(&rq->ipi_list, list);
-
-       /*
-        * If the list only contains our just added request, signal a raise of
-        * the softirq.  If there are already entries there, someone already
-        * raised the irq but it hasn't run yet.
-        */
-       if (list->next == &rq->ipi_list)
-               raise_softirq_irqoff(BLOCK_SOFTIRQ);
-       local_irq_restore(flags);
+       blk_complete_reqs(this_cpu_ptr(&blk_cpu_done));
 }
 
 static int blk_softirq_cpu_dead(unsigned int cpu)
 {
-       /*
-        * If a CPU goes away, splice its entries to the current CPU
-        * and trigger a run of the softirq
-        */
-       local_irq_disable();
-       list_splice_init(&per_cpu(blk_cpu_done, cpu),
-                        this_cpu_ptr(&blk_cpu_done));
-       raise_softirq_irqoff(BLOCK_SOFTIRQ);
-       local_irq_enable();
-
+       blk_complete_reqs(&per_cpu(blk_cpu_done, cpu));
        return 0;
 }
 
-
 static void __blk_mq_complete_request_remote(void *data)
 {
-       struct request *rq = data;
-
-       /*
-        * For most of single queue controllers, there is only one irq vector
-        * for handling I/O completion, and the only irq's affinity is set
-        * to all possible CPUs.  On most of ARCHs, this affinity means the irq
-        * is handled on one specific CPU.
-        *
-        * So complete I/O requests in softirq context in case of single queue
-        * devices to avoid degrading I/O performance due to irqsoff latency.
-        */
-       if (rq->q->nr_hw_queues == 1)
-               blk_mq_trigger_softirq(rq);
-       else
-               rq->q->mq_ops->complete(rq);
+       __raise_softirq_irqoff(BLOCK_SOFTIRQ);
 }
 
 static inline bool blk_mq_complete_need_ipi(struct request *rq)
@@ -648,6 +597,14 @@ static inline bool blk_mq_complete_need_ipi(struct request *rq)
        if (!IS_ENABLED(CONFIG_SMP) ||
            !test_bit(QUEUE_FLAG_SAME_COMP, &rq->q->queue_flags))
                return false;
+       /*
+        * With force threaded interrupts enabled, raising softirq from an SMP
+        * function call will always result in waking the ksoftirqd thread.
+        * This is probably worse than completing the request on a different
+        * cache domain.
+        */
+       if (force_irqthreads)
+               return false;
 
        /* same CPU or cache domain?  Complete locally */
        if (cpu == rq->mq_ctx->cpu ||
@@ -659,6 +616,32 @@ static inline bool blk_mq_complete_need_ipi(struct request *rq)
        return cpu_online(rq->mq_ctx->cpu);
 }
 
+static void blk_mq_complete_send_ipi(struct request *rq)
+{
+       struct llist_head *list;
+       unsigned int cpu;
+
+       cpu = rq->mq_ctx->cpu;
+       list = &per_cpu(blk_cpu_done, cpu);
+       if (llist_add(&rq->ipi_list, list)) {
+               rq->csd.func = __blk_mq_complete_request_remote;
+               rq->csd.info = rq;
+               rq->csd.flags = 0;
+               smp_call_function_single_async(cpu, &rq->csd);
+       }
+}
+
+static void blk_mq_raise_softirq(struct request *rq)
+{
+       struct llist_head *list;
+
+       preempt_disable();
+       list = this_cpu_ptr(&blk_cpu_done);
+       if (llist_add(&rq->ipi_list, list))
+               raise_softirq(BLOCK_SOFTIRQ);
+       preempt_enable();
+}
+
 bool blk_mq_complete_request_remote(struct request *rq)
 {
        WRITE_ONCE(rq->state, MQ_RQ_COMPLETE);
@@ -671,17 +654,15 @@ bool blk_mq_complete_request_remote(struct request *rq)
                return false;
 
        if (blk_mq_complete_need_ipi(rq)) {
-               rq->csd.func = __blk_mq_complete_request_remote;
-               rq->csd.info = rq;
-               rq->csd.flags = 0;
-               smp_call_function_single_async(rq->mq_ctx->cpu, &rq->csd);
-       } else {
-               if (rq->q->nr_hw_queues > 1)
-                       return false;
-               blk_mq_trigger_softirq(rq);
+               blk_mq_complete_send_ipi(rq);
+               return true;
        }
 
-       return true;
+       if (rq->q->nr_hw_queues == 1) {
+               blk_mq_raise_softirq(rq);
+               return true;
+       }
+       return false;
 }
 EXPORT_SYMBOL_GPL(blk_mq_complete_request_remote);
 
@@ -1589,14 +1570,14 @@ static void __blk_mq_delay_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_mod_delayed_work_on(blk_mq_hctx_next_cpu(hctx), &hctx->run_work,
@@ -3979,7 +3960,7 @@ static int __init blk_mq_init(void)
        int i;
 
        for_each_possible_cpu(i)
-               INIT_LIST_HEAD(&per_cpu(blk_cpu_done, i));
+               init_llist_head(&per_cpu(blk_cpu_done, i));
        open_softirq(BLOCK_SOFTIRQ, blk_done_softirq);
 
        cpuhp_setup_state_nocalls(CPUHP_BLOCK_SOFTIRQ_DEAD,
index a1bea0f..5f8ca8c 100644 (file)
@@ -36,6 +36,7 @@ static struct workqueue_struct *cryptd_wq;
 struct cryptd_cpu_queue {
        struct crypto_queue queue;
        struct work_struct work;
+       spinlock_t qlock;
 };
 
 struct cryptd_queue {
@@ -105,6 +106,7 @@ static int cryptd_init_queue(struct cryptd_queue *queue,
                cpu_queue = per_cpu_ptr(queue->cpu_queue, cpu);
                crypto_init_queue(&cpu_queue->queue, max_cpu_qlen);
                INIT_WORK(&cpu_queue->work, cryptd_queue_worker);
+               spin_lock_init(&cpu_queue->qlock);
        }
        pr_info("cryptd: max_cpu_qlen set to %d\n", max_cpu_qlen);
        return 0;
@@ -129,8 +131,10 @@ static int cryptd_enqueue_request(struct cryptd_queue *queue,
        struct cryptd_cpu_queue *cpu_queue;
        refcount_t *refcnt;
 
-       cpu = get_cpu();
-       cpu_queue = this_cpu_ptr(queue->cpu_queue);
+       cpu_queue = raw_cpu_ptr(queue->cpu_queue);
+       spin_lock_bh(&cpu_queue->qlock);
+       cpu = smp_processor_id();
+
        err = crypto_enqueue_request(&cpu_queue->queue, request);
 
        refcnt = crypto_tfm_ctx(request->tfm);
@@ -146,7 +150,7 @@ static int cryptd_enqueue_request(struct cryptd_queue *queue,
        refcount_inc(refcnt);
 
 out_put_cpu:
-       put_cpu();
+       spin_unlock_bh(&cpu_queue->qlock);
 
        return err;
 }
@@ -162,16 +166,11 @@ static void cryptd_queue_worker(struct work_struct *work)
        cpu_queue = container_of(work, struct cryptd_cpu_queue, work);
        /*
         * Only handle one request at a time to avoid hogging crypto workqueue.
-        * preempt_disable/enable is used to prevent being preempted by
-        * cryptd_enqueue_request(). local_bh_disable/enable is used to prevent
-        * cryptd_enqueue_request() being accessed from software interrupts.
         */
-       local_bh_disable();
-       preempt_disable();
+       spin_lock_bh(&cpu_queue->qlock);
        backlog = crypto_get_backlog(&cpu_queue->queue);
        req = crypto_dequeue_request(&cpu_queue->queue);
-       preempt_enable();
-       local_bh_enable();
+       spin_unlock_bh(&cpu_queue->qlock);
 
        if (!req)
                return;
index b574cce..422753d 100644 (file)
@@ -2054,7 +2054,7 @@ static int eni_send(struct atm_vcc *vcc,struct sk_buff *skb)
        }
        submitted++;
        ATM_SKB(skb)->vcc = vcc;
-       tasklet_disable(&ENI_DEV(vcc->dev)->task);
+       tasklet_disable_in_atomic(&ENI_DEV(vcc->dev)->task);
        res = do_tx(skb);
        tasklet_enable(&ENI_DEV(vcc->dev)->task);
        if (res == enq_ok) return 0;
index 0636df6..1a7523c 100644 (file)
@@ -59,6 +59,40 @@ static void zram_free_page(struct zram *zram, size_t index);
 static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec,
                                u32 index, int offset, struct bio *bio);
 
+#ifdef CONFIG_PREEMPT_RT
+static void zram_meta_init_table_locks(struct zram *zram, size_t num_pages)
+{
+       size_t index;
+
+       for (index = 0; index < num_pages; index++)
+               spin_lock_init(&zram->table[index].lock);
+}
+
+static int zram_slot_trylock(struct zram *zram, u32 index)
+{
+       int ret;
+
+       ret = spin_trylock(&zram->table[index].lock);
+       if (ret)
+               __set_bit(ZRAM_LOCK, &zram->table[index].flags);
+       return ret;
+}
+
+static void zram_slot_lock(struct zram *zram, u32 index)
+{
+       spin_lock(&zram->table[index].lock);
+       __set_bit(ZRAM_LOCK, &zram->table[index].flags);
+}
+
+static void zram_slot_unlock(struct zram *zram, u32 index)
+{
+       __clear_bit(ZRAM_LOCK, &zram->table[index].flags);
+       spin_unlock(&zram->table[index].lock);
+}
+
+#else
+
+static void zram_meta_init_table_locks(struct zram *zram, size_t num_pages) { }
 
 static int zram_slot_trylock(struct zram *zram, u32 index)
 {
@@ -74,6 +108,7 @@ static void zram_slot_unlock(struct zram *zram, u32 index)
 {
        bit_spin_unlock(ZRAM_LOCK, &zram->table[index].flags);
 }
+#endif
 
 static inline bool init_done(struct zram *zram)
 {
@@ -1165,6 +1200,7 @@ static bool zram_meta_alloc(struct zram *zram, u64 disksize)
 
        if (!huge_class_size)
                huge_class_size = zs_huge_class_size(zram->mem_pool);
+       zram_meta_init_table_locks(zram, num_pages);
        return true;
 }
 
index f2fd46d..7e4dd44 100644 (file)
@@ -63,6 +63,7 @@ struct zram_table_entry {
                unsigned long element;
        };
        unsigned long flags;
+       spinlock_t lock;
 #ifdef CONFIG_ZRAM_MEMORY_TRACKING
        ktime_t ac_time;
 #endif
index 5444206..7b0b1fe 100644 (file)
@@ -1272,28 +1272,27 @@ 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);
index 1784530..c08cbb3 100644 (file)
@@ -20,7 +20,6 @@
 #include "tpm-dev.h"
 
 static struct workqueue_struct *tpm_dev_wq;
-static DEFINE_MUTEX(tpm_dev_wq_lock);
 
 static ssize_t tpm_dev_transmit(struct tpm_chip *chip, struct tpm_space *space,
                                u8 *buf, size_t bufsiz)
index 4ed6e66..c2bd0d4 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
+/*
+ * 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 int interrupts = -1;
 module_param(interrupts, int, 0444);
 MODULE_PARM_DESC(interrupts, "Enable interrupts");
@@ -169,7 +194,7 @@ 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;
 }
@@ -196,7 +221,7 @@ 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 9811c40..17c9d82 100644 (file)
@@ -2545,7 +2545,7 @@ static int ohci_cancel_packet(struct fw_card *card, struct fw_packet *packet)
        struct driver_data *driver_data = packet->driver_data;
        int ret = -ENOENT;
 
-       tasklet_disable(&ctx->tasklet);
+       tasklet_disable_in_atomic(&ctx->tasklet);
 
        if (packet->ack != 0)
                goto out;
@@ -3465,7 +3465,7 @@ static int ohci_flush_iso_completions(struct fw_iso_context *base)
        struct iso_context *ctx = container_of(base, struct iso_context, base);
        int ret = 0;
 
-       tasklet_disable(&ctx->context.tasklet);
+       tasklet_disable_in_atomic(&ctx->context.tasklet);
 
        if (!test_and_set_bit_lock(0, &ctx->flushing_completions)) {
                context_tasklet((unsigned long)&ctx->context);
index 847f33f..ae79c33 100644 (file)
@@ -66,7 +66,7 @@ struct mm_struct efi_mm = {
 
 struct workqueue_struct *efi_rts_wq;
 
-static bool disable_runtime;
+static bool disable_runtime = IS_ENABLED(CONFIG_PREEMPT_RT);
 static int __init setup_noefi(char *arg)
 {
        disable_runtime = true;
@@ -97,6 +97,9 @@ static int __init parse_efi_cmdline(char *str)
        if (parse_option_str(str, "noruntime"))
                disable_runtime = true;
 
+       if (parse_option_str(str, "runtime"))
+               disable_runtime = false;
+
        if (parse_option_str(str, "nosoftreserve"))
                set_bit(EFI_MEM_NO_SOFT_RESERVE, &efi.flags);
 
index 12f7128..a65061e 100644 (file)
@@ -118,7 +118,8 @@ void intel_pipe_update_start(const struct intel_crtc_state *new_crtc_state)
                        "PSR idle timed out 0x%x, atomic update may fail\n",
                        psr_status);
 
-       local_irq_disable();
+       if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+               local_irq_disable();
 
        crtc->debug.min_vbl = min;
        crtc->debug.max_vbl = max;
@@ -143,11 +144,13 @@ void intel_pipe_update_start(const struct intel_crtc_state *new_crtc_state)
                        break;
                }
 
-               local_irq_enable();
+               if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+                       local_irq_enable();
 
                timeout = schedule_timeout(timeout);
 
-               local_irq_disable();
+               if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+                       local_irq_disable();
        }
 
        finish_wait(wq, &wait);
@@ -180,7 +183,8 @@ void intel_pipe_update_start(const struct intel_crtc_state *new_crtc_state)
        return;
 
 irq_disable:
-       local_irq_disable();
+       if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+               local_irq_disable();
 }
 
 /**
@@ -218,7 +222,8 @@ void intel_pipe_update_end(struct intel_crtc_state *new_crtc_state)
                new_crtc_state->uapi.event = NULL;
        }
 
-       local_irq_enable();
+       if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+               local_irq_enable();
 
        if (intel_vgpu_active(dev_priv))
                return;
index 0c083af..2abf043 100644 (file)
@@ -1080,7 +1080,7 @@ static void reloc_cache_reset(struct reloc_cache *cache, struct i915_execbuffer
                struct i915_ggtt *ggtt = cache_to_ggtt(cache);
 
                intel_gt_flush_ggtt_writes(ggtt->vm.gt);
-               io_mapping_unmap_atomic((void __iomem *)vaddr);
+               io_mapping_unmap_local((void __iomem *)vaddr);
 
                if (drm_mm_node_allocated(&cache->node)) {
                        ggtt->vm.clear_range(&ggtt->vm,
@@ -1146,7 +1146,7 @@ static void *reloc_iomap(struct drm_i915_gem_object *obj,
 
        if (cache->vaddr) {
                intel_gt_flush_ggtt_writes(ggtt->vm.gt);
-               io_mapping_unmap_atomic((void __force __iomem *) unmask_page(cache->vaddr));
+               io_mapping_unmap_local((void __force __iomem *) unmask_page(cache->vaddr));
        } else {
                struct i915_vma *vma;
                int err;
@@ -1194,8 +1194,7 @@ static void *reloc_iomap(struct drm_i915_gem_object *obj,
                offset += page << PAGE_SHIFT;
        }
 
-       vaddr = (void __force *)io_mapping_map_atomic_wc(&ggtt->iomap,
-                                                        offset);
+       vaddr = (void __force *)io_mapping_map_local_wc(&ggtt->iomap, offset);
        cache->page = page;
        cache->vaddr = (unsigned long)vaddr;
 
index 0040b47..3f4f854 100644 (file)
@@ -342,10 +342,9 @@ void intel_breadcrumbs_park(struct intel_breadcrumbs *b)
        /* Kick the work once more to drain the signalers */
        irq_work_sync(&b->irq_work);
        while (unlikely(READ_ONCE(b->irq_armed))) {
-               local_irq_disable();
-               signal_irq_work(&b->irq_work);
-               local_irq_enable();
+               irq_work_queue(&b->irq_work);
                cond_resched();
+               irq_work_sync(&b->irq_work);
        }
        GEM_BUG_ON(!list_empty(&b->signalers));
 }
index f7b2e07..313d8a2 100644 (file)
@@ -60,9 +60,10 @@ static int __engine_unpark(struct intel_wakeref *wf)
 
 static inline unsigned long __timeline_mark_lock(struct intel_context *ce)
 {
-       unsigned long flags;
+       unsigned long flags = 0;
 
-       local_irq_save(flags);
+       if (!force_irqthreads)
+               local_irq_save(flags);
        mutex_acquire(&ce->timeline->mutex.dep_map, 2, 0, _THIS_IP_);
 
        return flags;
@@ -72,7 +73,8 @@ static inline void __timeline_mark_unlock(struct intel_context *ce,
                                          unsigned long flags)
 {
        mutex_release(&ce->timeline->mutex.dep_map, _THIS_IP_);
-       local_irq_restore(flags);
+       if (!force_irqthreads)
+               local_irq_restore(flags);
 }
 
 #else
index 5827669..88944c3 100644 (file)
@@ -355,22 +355,15 @@ gtt_user_read(struct io_mapping *mapping,
              char __user *user_data, int length)
 {
        void __iomem *vaddr;
-       unsigned long unwritten;
+       bool fail = false;
 
        /* We can use the cpu mem copy function because this is X86. */
-       vaddr = io_mapping_map_atomic_wc(mapping, base);
-       unwritten = __copy_to_user_inatomic(user_data,
-                                           (void __force *)vaddr + offset,
-                                           length);
-       io_mapping_unmap_atomic(vaddr);
-       if (unwritten) {
-               vaddr = io_mapping_map_wc(mapping, base, PAGE_SIZE);
-               unwritten = copy_to_user(user_data,
-                                        (void __force *)vaddr + offset,
-                                        length);
-               io_mapping_unmap(vaddr);
-       }
-       return unwritten;
+       vaddr = io_mapping_map_local_wc(mapping, base);
+       if (copy_to_user(user_data, (void __force *)vaddr + offset, length))
+               fail = true;
+       io_mapping_unmap_local(vaddr);
+
+       return fail;
 }
 
 static int
@@ -539,21 +532,14 @@ ggtt_write(struct io_mapping *mapping,
           char __user *user_data, int length)
 {
        void __iomem *vaddr;
-       unsigned long unwritten;
+       bool fail = false;
 
        /* We can use the cpu mem copy function because this is X86. */
-       vaddr = io_mapping_map_atomic_wc(mapping, base);
-       unwritten = __copy_from_user_inatomic_nocache((void __force *)vaddr + offset,
-                                                     user_data, length);
-       io_mapping_unmap_atomic(vaddr);
-       if (unwritten) {
-               vaddr = io_mapping_map_wc(mapping, base, PAGE_SIZE);
-               unwritten = copy_from_user((void __force *)vaddr + offset,
-                                          user_data, length);
-               io_mapping_unmap(vaddr);
-       }
-
-       return unwritten;
+       vaddr = io_mapping_map_local_wc(mapping, base);
+       if (copy_from_user((void __force *)vaddr + offset, user_data, length))
+               fail = true;
+       io_mapping_unmap_local(vaddr);
+       return fail;
 }
 
 /**
index 759f523..7339a42 100644 (file)
@@ -847,6 +847,7 @@ static bool i915_get_crtc_scanoutpos(struct drm_crtc *_crtc,
        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)
@@ -898,6 +899,7 @@ static bool i915_get_crtc_scanoutpos(struct drm_crtc *_crtc,
                *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 a4addcc..396b659 100644 (file)
@@ -2,6 +2,10 @@
 #if !defined(_I915_TRACE_H_) || defined(TRACE_HEADER_MULTI_READ)
 #define _I915_TRACE_H_
 
+#ifdef CONFIG_PREEMPT_RT
+#define NOTRACE
+#endif
+
 #include <linux/stringify.h>
 #include <linux/types.h>
 #include <linux/tracepoint.h>
@@ -778,7 +782,7 @@ DEFINE_EVENT(i915_request, i915_request_add,
            TP_ARGS(rq)
 );
 
-#if defined(CONFIG_DRM_I915_LOW_LEVEL_TRACEPOINTS)
+#if defined(CONFIG_DRM_I915_LOW_LEVEL_TRACEPOINTS) && !defined(NOTRACE)
 DEFINE_EVENT(i915_request, i915_request_submit,
             TP_PROTO(struct i915_request *rq),
             TP_ARGS(rq)
index 412e216..4324931 100644 (file)
@@ -57,12 +57,12 @@ static void trash_stolen(struct drm_i915_private *i915)
 
                ggtt->vm.insert_page(&ggtt->vm, dma, slot, I915_CACHE_NONE, 0);
 
-               s = io_mapping_map_atomic_wc(&ggtt->iomap, slot);
+               s = io_mapping_map_local_wc(&ggtt->iomap, slot);
                for (x = 0; x < PAGE_SIZE / sizeof(u32); x++) {
                        prng = next_pseudo_random32(prng);
                        iowrite32(prng, &s[x]);
                }
-               io_mapping_unmap_atomic(s);
+               io_mapping_unmap_local(s);
        }
 
        ggtt->vm.clear_range(&ggtt->vm, slot, PAGE_SIZE);
index 65e28c4..ca48328 100644 (file)
@@ -1201,9 +1201,9 @@ static int igt_ggtt_page(void *arg)
                u64 offset = tmp.start + order[n] * PAGE_SIZE;
                u32 __iomem *vaddr;
 
-               vaddr = io_mapping_map_atomic_wc(&ggtt->iomap, offset);
+               vaddr = io_mapping_map_local_wc(&ggtt->iomap, offset);
                iowrite32(n, vaddr + n);
-               io_mapping_unmap_atomic(vaddr);
+               io_mapping_unmap_local(vaddr);
        }
        intel_gt_flush_ggtt_writes(ggtt->vm.gt);
 
@@ -1213,9 +1213,9 @@ static int igt_ggtt_page(void *arg)
                u32 __iomem *vaddr;
                u32 val;
 
-               vaddr = io_mapping_map_atomic_wc(&ggtt->iomap, offset);
+               vaddr = io_mapping_map_local_wc(&ggtt->iomap, offset);
                val = ioread32(vaddr + n);
-               io_mapping_unmap_atomic(vaddr);
+               io_mapping_unmap_local(vaddr);
 
                if (val != n) {
                        pr_err("insert page failed: found %d, expected %d\n",
index 6c5bbff..411f91e 100644 (file)
@@ -60,19 +60,19 @@ fbmem_fini(struct io_mapping *fb)
 static inline u32
 fbmem_peek(struct io_mapping *fb, u32 off)
 {
-       u8 __iomem *p = io_mapping_map_atomic_wc(fb, off & PAGE_MASK);
+       u8 __iomem *p = io_mapping_map_local_wc(fb, off & PAGE_MASK);
        u32 val = ioread32(p + (off & ~PAGE_MASK));
-       io_mapping_unmap_atomic(p);
+       io_mapping_unmap_local(p);
        return val;
 }
 
 static inline void
 fbmem_poke(struct io_mapping *fb, u32 off, u32 val)
 {
-       u8 __iomem *p = io_mapping_map_atomic_wc(fb, off & PAGE_MASK);
+       u8 __iomem *p = io_mapping_map_local_wc(fb, off & PAGE_MASK);
        iowrite32(val, p + (off & ~PAGE_MASK));
        wmb();
-       io_mapping_unmap_atomic(p);
+       io_mapping_unmap_local(p);
 }
 
 static inline bool
index 60ab715..93f92cc 100644 (file)
@@ -124,12 +124,12 @@ qxl_image_init_helper(struct qxl_device *qdev,
                                  wrong (check the bitmaps are sent correctly
                                  first) */
 
-       ptr = qxl_bo_kmap_atomic_page(qdev, chunk_bo, 0);
+       ptr = qxl_bo_kmap_local_page(qdev, chunk_bo, 0);
        chunk = ptr;
        chunk->data_size = height * chunk_stride;
        chunk->prev_chunk = 0;
        chunk->next_chunk = 0;
-       qxl_bo_kunmap_atomic_page(qdev, chunk_bo, ptr);
+       qxl_bo_kunmap_local_page(qdev, chunk_bo, ptr);
 
        {
                void *k_data, *i_data;
@@ -143,7 +143,7 @@ qxl_image_init_helper(struct qxl_device *qdev,
                        i_data = (void *)data;
 
                        while (remain > 0) {
-                               ptr = qxl_bo_kmap_atomic_page(qdev, chunk_bo, page << PAGE_SHIFT);
+                               ptr = qxl_bo_kmap_local_page(qdev, chunk_bo, page << PAGE_SHIFT);
 
                                if (page == 0) {
                                        chunk = ptr;
@@ -157,7 +157,7 @@ qxl_image_init_helper(struct qxl_device *qdev,
 
                                memcpy(k_data, i_data, size);
 
-                               qxl_bo_kunmap_atomic_page(qdev, chunk_bo, ptr);
+                               qxl_bo_kunmap_local_page(qdev, chunk_bo, ptr);
                                i_data += size;
                                remain -= size;
                                page++;
@@ -175,10 +175,10 @@ qxl_image_init_helper(struct qxl_device *qdev,
                                        page_offset = offset_in_page(out_offset);
                                        size = min((int)(PAGE_SIZE - page_offset), remain);
 
-                                       ptr = qxl_bo_kmap_atomic_page(qdev, chunk_bo, page_base);
+                                       ptr = qxl_bo_kmap_local_page(qdev, chunk_bo, page_base);
                                        k_data = ptr + page_offset;
                                        memcpy(k_data, i_data, size);
-                                       qxl_bo_kunmap_atomic_page(qdev, chunk_bo, ptr);
+                                       qxl_bo_kunmap_local_page(qdev, chunk_bo, ptr);
                                        remain -= size;
                                        i_data += size;
                                        out_offset += size;
@@ -189,7 +189,7 @@ qxl_image_init_helper(struct qxl_device *qdev,
        qxl_bo_kunmap(chunk_bo);
 
        image_bo = dimage->bo;
-       ptr = qxl_bo_kmap_atomic_page(qdev, image_bo, 0);
+       ptr = qxl_bo_kmap_local_page(qdev, image_bo, 0);
        image = ptr;
 
        image->descriptor.id = 0;
@@ -212,7 +212,7 @@ qxl_image_init_helper(struct qxl_device *qdev,
                break;
        default:
                DRM_ERROR("unsupported image bit depth\n");
-               qxl_bo_kunmap_atomic_page(qdev, image_bo, ptr);
+               qxl_bo_kunmap_local_page(qdev, image_bo, ptr);
                return -EINVAL;
        }
        image->u.bitmap.flags = QXL_BITMAP_TOP_DOWN;
@@ -222,7 +222,7 @@ qxl_image_init_helper(struct qxl_device *qdev,
        image->u.bitmap.palette = 0;
        image->u.bitmap.data = qxl_bo_physical_address(qdev, chunk_bo, 0);
 
-       qxl_bo_kunmap_atomic_page(qdev, image_bo, ptr);
+       qxl_bo_kunmap_local_page(qdev, image_bo, ptr);
 
        return 0;
 }
index 5cea6ee..7850230 100644 (file)
@@ -89,11 +89,11 @@ apply_reloc(struct qxl_device *qdev, struct qxl_reloc_info *info)
 {
        void *reloc_page;
 
-       reloc_page = qxl_bo_kmap_atomic_page(qdev, info->dst_bo, info->dst_offset & PAGE_MASK);
+       reloc_page = qxl_bo_kmap_local_page(qdev, info->dst_bo, info->dst_offset & PAGE_MASK);
        *(uint64_t *)(reloc_page + (info->dst_offset & ~PAGE_MASK)) = qxl_bo_physical_address(qdev,
                                                                                              info->src_bo,
                                                                                              info->src_offset);
-       qxl_bo_kunmap_atomic_page(qdev, info->dst_bo, reloc_page);
+       qxl_bo_kunmap_local_page(qdev, info->dst_bo, reloc_page);
 }
 
 static void
@@ -105,9 +105,9 @@ apply_surf_reloc(struct qxl_device *qdev, struct qxl_reloc_info *info)
        if (info->src_bo && !info->src_bo->is_primary)
                id = info->src_bo->surface_id;
 
-       reloc_page = qxl_bo_kmap_atomic_page(qdev, info->dst_bo, info->dst_offset & PAGE_MASK);
+       reloc_page = qxl_bo_kmap_local_page(qdev, info->dst_bo, info->dst_offset & PAGE_MASK);
        *(uint32_t *)(reloc_page + (info->dst_offset & ~PAGE_MASK)) = id;
-       qxl_bo_kunmap_atomic_page(qdev, info->dst_bo, reloc_page);
+       qxl_bo_kunmap_local_page(qdev, info->dst_bo, reloc_page);
 }
 
 /* return holding the reference to this object */
@@ -149,7 +149,6 @@ static int qxl_process_single_command(struct qxl_device *qdev,
        struct qxl_bo *cmd_bo;
        void *fb_cmd;
        int i, ret, num_relocs;
-       int unwritten;
 
        switch (cmd->type) {
        case QXL_CMD_DRAW:
@@ -185,21 +184,21 @@ static int qxl_process_single_command(struct qxl_device *qdev,
                goto out_free_reloc;
 
        /* TODO copy slow path code from i915 */
-       fb_cmd = qxl_bo_kmap_atomic_page(qdev, cmd_bo, (release->release_offset & PAGE_MASK));
-       unwritten = __copy_from_user_inatomic_nocache
-               (fb_cmd + sizeof(union qxl_release_info) + (release->release_offset & ~PAGE_MASK),
-                u64_to_user_ptr(cmd->command), cmd->command_size);
+       fb_cmd = qxl_bo_kmap_local_page(qdev, cmd_bo, (release->release_offset & PAGE_MASK));
 
-       {
+       if (copy_from_user(fb_cmd + sizeof(union qxl_release_info) +
+                          (release->release_offset & ~PAGE_MASK),
+                          u64_to_user_ptr(cmd->command), cmd->command_size)) {
+               ret = -EFAULT;
+       } else {
                struct qxl_drawable *draw = fb_cmd;
 
                draw->mm_time = qdev->rom->mm_clock;
        }
 
-       qxl_bo_kunmap_atomic_page(qdev, cmd_bo, fb_cmd);
-       if (unwritten) {
-               DRM_ERROR("got unwritten %d\n", unwritten);
-               ret = -EFAULT;
+       qxl_bo_kunmap_local_page(qdev, cmd_bo, fb_cmd);
+       if (ret) {
+               DRM_ERROR("copy from user failed %d\n", ret);
                goto out_free_release;
        }
 
index 544a9e4..5ee5171 100644 (file)
@@ -173,8 +173,8 @@ int qxl_bo_kmap(struct qxl_bo *bo, void **ptr)
        return 0;
 }
 
-void *qxl_bo_kmap_atomic_page(struct qxl_device *qdev,
-                             struct qxl_bo *bo, int page_offset)
+void *qxl_bo_kmap_local_page(struct qxl_device *qdev,
+                            struct qxl_bo *bo, int page_offset)
 {
        unsigned long offset;
        void *rptr;
@@ -189,7 +189,7 @@ void *qxl_bo_kmap_atomic_page(struct qxl_device *qdev,
                goto fallback;
 
        offset = bo->tbo.mem.start << PAGE_SHIFT;
-       return io_mapping_map_atomic_wc(map, offset + page_offset);
+       return io_mapping_map_local_wc(map, offset + page_offset);
 fallback:
        if (bo->kptr) {
                rptr = bo->kptr + (page_offset * PAGE_SIZE);
@@ -215,14 +215,14 @@ void qxl_bo_kunmap(struct qxl_bo *bo)
        ttm_bo_kunmap(&bo->kmap);
 }
 
-void qxl_bo_kunmap_atomic_page(struct qxl_device *qdev,
-                              struct qxl_bo *bo, void *pmap)
+void qxl_bo_kunmap_local_page(struct qxl_device *qdev,
+                             struct qxl_bo *bo, void *pmap)
 {
        if ((bo->tbo.mem.mem_type != TTM_PL_VRAM) &&
            (bo->tbo.mem.mem_type != TTM_PL_PRIV))
                goto fallback;
 
-       io_mapping_unmap_atomic(pmap);
+       io_mapping_unmap_local(pmap);
        return;
  fallback:
        qxl_bo_kunmap(bo);
index 5762ea4..6ae89b1 100644 (file)
@@ -89,8 +89,8 @@ extern int qxl_bo_create(struct qxl_device *qdev,
                         struct qxl_bo **bo_ptr);
 extern int qxl_bo_kmap(struct qxl_bo *bo, void **ptr);
 extern void qxl_bo_kunmap(struct qxl_bo *bo);
-void *qxl_bo_kmap_atomic_page(struct qxl_device *qdev, struct qxl_bo *bo, int page_offset);
-void qxl_bo_kunmap_atomic_page(struct qxl_device *qdev, struct qxl_bo *bo, void *map);
+void *qxl_bo_kmap_local_page(struct qxl_device *qdev, struct qxl_bo *bo, int page_offset);
+void qxl_bo_kunmap_local_page(struct qxl_device *qdev, struct qxl_bo *bo, void *map);
 extern struct qxl_bo *qxl_bo_ref(struct qxl_bo *bo);
 extern void qxl_bo_unref(struct qxl_bo **bo);
 extern int qxl_bo_pin(struct qxl_bo *bo);
index b2a475a..b665a33 100644 (file)
@@ -414,7 +414,7 @@ union qxl_release_info *qxl_release_map(struct qxl_device *qdev,
        union qxl_release_info *info;
        struct qxl_bo *bo = release->release_bo;
 
-       ptr = qxl_bo_kmap_atomic_page(qdev, bo, release->release_offset & PAGE_MASK);
+       ptr = qxl_bo_kmap_local_page(qdev, bo, release->release_offset & PAGE_MASK);
        if (!ptr)
                return NULL;
        info = ptr + (release->release_offset & ~PAGE_MASK);
@@ -429,7 +429,7 @@ void qxl_release_unmap(struct qxl_device *qdev,
        void *ptr;
 
        ptr = ((void *)info) - (release->release_offset & ~PAGE_MASK);
-       qxl_bo_kunmap_atomic_page(qdev, bo, ptr);
+       qxl_bo_kunmap_local_page(qdev, bo, ptr);
 }
 
 void qxl_release_fence_buffer_objects(struct qxl_release *release)
index 71bdafa..95ce311 100644 (file)
@@ -1823,6 +1823,7 @@ 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)
@@ -1915,6 +1916,7 @@ 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 fb2a25f..164b9a0 100644 (file)
@@ -181,13 +181,15 @@ static int ttm_copy_io_ttm_page(struct ttm_tt *ttm, void *src,
                return -ENOMEM;
 
        src = (void *)((unsigned long)src + (page << PAGE_SHIFT));
-       dst = kmap_atomic_prot(d, prot);
-       if (!dst)
-               return -ENOMEM;
+       /*
+        * Ensure that a highmem page is mapped with the correct
+        * pgprot. For non highmem the mapping is already there.
+        */
+       dst = kmap_local_page_prot(d, prot);
 
        memcpy_fromio(dst, src, PAGE_SIZE);
 
-       kunmap_atomic(dst);
+       kunmap_local(dst);
 
        return 0;
 }
@@ -203,13 +205,15 @@ static int ttm_copy_ttm_io_page(struct ttm_tt *ttm, void *dst,
                return -ENOMEM;
 
        dst = (void *)((unsigned long)dst + (page << PAGE_SHIFT));
-       src = kmap_atomic_prot(s, prot);
-       if (!src)
-               return -ENOMEM;
+       /*
+        * Ensure that a highmem page is mapped with the correct
+        * pgprot. For non highmem the mapping is already there.
+        */
+       src = kmap_local_page_prot(s, prot);
 
        memcpy_toio(dst, src, PAGE_SIZE);
 
-       kunmap_atomic(src);
+       kunmap_local(src);
 
        return 0;
 }
index e8d6618..71dba22 100644 (file)
@@ -375,12 +375,12 @@ static int vmw_bo_cpu_blit_line(struct vmw_bo_blit_line_data *d,
                copy_size = min_t(u32, copy_size, PAGE_SIZE - src_page_offset);
 
                if (unmap_src) {
-                       kunmap_atomic(d->src_addr);
+                       kunmap_local(d->src_addr);
                        d->src_addr = NULL;
                }
 
                if (unmap_dst) {
-                       kunmap_atomic(d->dst_addr);
+                       kunmap_local(d->dst_addr);
                        d->dst_addr = NULL;
                }
 
@@ -388,12 +388,8 @@ static int vmw_bo_cpu_blit_line(struct vmw_bo_blit_line_data *d,
                        if (WARN_ON_ONCE(dst_page >= d->dst_num_pages))
                                return -EINVAL;
 
-                       d->dst_addr =
-                               kmap_atomic_prot(d->dst_pages[dst_page],
-                                                d->dst_prot);
-                       if (!d->dst_addr)
-                               return -ENOMEM;
-
+                       d->dst_addr = kmap_local_page_prot(d->dst_pages[dst_page],
+                                                          d->dst_prot);
                        d->mapped_dst = dst_page;
                }
 
@@ -401,12 +397,8 @@ static int vmw_bo_cpu_blit_line(struct vmw_bo_blit_line_data *d,
                        if (WARN_ON_ONCE(src_page >= d->src_num_pages))
                                return -EINVAL;
 
-                       d->src_addr =
-                               kmap_atomic_prot(d->src_pages[src_page],
-                                                d->src_prot);
-                       if (!d->src_addr)
-                               return -ENOMEM;
-
+                       d->src_addr = kmap_local_page_prot(d->src_pages[src_page],
+                                                          d->src_prot);
                        d->mapped_src = src_page;
                }
                diff->do_cpy(diff, d->dst_addr + dst_page_offset,
@@ -436,8 +428,10 @@ static int vmw_bo_cpu_blit_line(struct vmw_bo_blit_line_data *d,
  *
  * Performs a CPU blit from one buffer object to another avoiding a full
  * bo vmap which may exhaust- or fragment vmalloc space.
- * On supported architectures (x86), we're using kmap_atomic which avoids
- * cross-processor TLB- and cache flushes and may, on non-HIGHMEM systems
+ *
+ * On supported architectures (x86), we're using kmap_local_prot() which
+ * avoids cross-processor TLB- and cache flushes. kmap_local_prot() will
+ * either map a highmem page with the proper pgprot on HIGHMEM=y systems or
  * reference already set-up mappings.
  *
  * Neither of the buffer objects may be placed in PCI memory
@@ -500,9 +494,9 @@ int vmw_bo_cpu_blit(struct ttm_buffer_object *dst,
        }
 out:
        if (d.src_addr)
-               kunmap_atomic(d.src_addr);
+               kunmap_local(d.src_addr);
        if (d.dst_addr)
-               kunmap_atomic(d.dst_addr);
+               kunmap_local(d.dst_addr);
 
        return ret;
 }
index 7845fa5..043e058 100644 (file)
@@ -19,6 +19,7 @@
 #include <linux/atomic.h>
 #include <linux/hyperv.h>
 #include <linux/interrupt.h>
+#include <linux/irq.h>
 
 #include "hv_trace.h"
 
index a5a402e..d0763ea 100644 (file)
@@ -22,6 +22,7 @@
 #include <linux/clockchips.h>
 #include <linux/cpu.h>
 #include <linux/sched/task_stack.h>
+#include <linux/irq.h>
 
 #include <linux/delay.h>
 #include <linux/notifier.h>
@@ -1307,6 +1308,8 @@ static void vmbus_isr(void)
        void *page_addr = hv_cpu->synic_event_page;
        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;
 
        if (unlikely(page_addr == NULL))
@@ -1351,7 +1354,7 @@ static void vmbus_isr(void)
                        tasklet_schedule(&hv_cpu->msg_dpc);
        }
 
-       add_interrupt_randomness(hv_get_vector(), 0);
+       add_interrupt_randomness(hv_get_vector(), 0, ip);
 }
 
 /*
@@ -1359,7 +1362,8 @@ static void vmbus_isr(void)
  * buffer and call into Hyper-V to transfer the data.
  */
 static void hv_kmsg_dump(struct kmsg_dumper *dumper,
-                        enum kmsg_dump_reason reason)
+                        enum kmsg_dump_reason reason,
+                        struct kmsg_dumper_iter *iter)
 {
        size_t bytes_written;
        phys_addr_t panic_pa;
@@ -1374,7 +1378,7 @@ static void hv_kmsg_dump(struct kmsg_dumper *dumper,
         * Write dump contents to the page. No need to synchronize; panic should
         * be single-threaded.
         */
-       kmsg_dump_get_buffer(dumper, false, hv_panic_page, HV_HYP_PAGE_SIZE,
+       kmsg_dump_get_buffer(iter, false, hv_panic_page, HV_HYP_PAGE_SIZE,
                             &bytes_written);
        if (bytes_written)
                hyperv_report_panic_msg(panic_pa, bytes_written);
index d45aba3..6e89013 100644 (file)
@@ -64,6 +64,7 @@ config LEDS_TRIGGER_BACKLIGHT
 
 config LEDS_TRIGGER_CPU
        bool "LED CPU Trigger"
+       depends on !PREEMPT_RT
        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 c82953a..061fea7 100644 (file)
@@ -2217,8 +2217,9 @@ 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++;
@@ -2277,7 +2278,8 @@ 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 void free_stripe(struct kmem_cache *sc, struct stripe_head *sh)
@@ -7099,6 +7101,7 @@ 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;
 }
 
index 5c05acf..665fe13 100644 (file)
@@ -635,6 +635,7 @@ 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 */
                void            *scribble;  /* space for constructing buffer
                                             * lists and performing address
index 774970b..6bc2c72 100644 (file)
@@ -267,7 +267,8 @@ static void find_next_position(struct mtdoops_context *cxt)
 }
 
 static void mtdoops_do_dump(struct kmsg_dumper *dumper,
-                           enum kmsg_dump_reason reason)
+                           enum kmsg_dump_reason reason,
+                           struct kmsg_dumper_iter *iter)
 {
        struct mtdoops_context *cxt = container_of(dumper,
                        struct mtdoops_context, dump);
@@ -276,7 +277,7 @@ static void mtdoops_do_dump(struct kmsg_dumper *dumper,
        if (reason == KMSG_DUMP_OOPS && !dump_oops)
                return;
 
-       kmsg_dump_get_buffer(dumper, true, cxt->oops_buf + MTDOOPS_HEADER_SIZE,
+       kmsg_dump_get_buffer(iter, true, cxt->oops_buf + MTDOOPS_HEADER_SIZE,
                             record_size - MTDOOPS_HEADER_SIZE, NULL);
 
        if (reason != KMSG_DUMP_OOPS) {
index 98df38f..12d0854 100644 (file)
@@ -332,7 +332,7 @@ static int __init arc_rimi_init(void)
                dev->irq = 9;
 
        if (arcrimi_probe(dev)) {
-               free_netdev(dev);
+               free_arcdev(dev);
                return -EIO;
        }
 
@@ -349,7 +349,7 @@ static void __exit arc_rimi_exit(void)
        iounmap(lp->mem_start);
        release_mem_region(dev->mem_start, dev->mem_end - dev->mem_start + 1);
        free_irq(dev->irq, dev);
-       free_netdev(dev);
+       free_arcdev(dev);
 }
 
 #ifndef MODULE
index 22a49c6..5d4a4c7 100644 (file)
@@ -298,6 +298,10 @@ struct arcnet_local {
 
        int excnak_pending;    /* We just got an excesive nak interrupt */
 
+       /* RESET flag handling */
+       int reset_in_progress;
+       struct work_struct reset_work;
+
        struct {
                uint16_t sequence;      /* sequence number (incs with each packet) */
                __be16 aborted_seq;
@@ -350,7 +354,9 @@ void arcnet_dump_skb(struct net_device *dev, struct sk_buff *skb, char *desc)
 
 void arcnet_unregister_proto(struct ArcProto *proto);
 irqreturn_t arcnet_interrupt(int irq, void *dev_id);
+
 struct net_device *alloc_arcdev(const char *name);
+void free_arcdev(struct net_device *dev);
 
 int arcnet_open(struct net_device *dev);
 int arcnet_close(struct net_device *dev);
index e04efc0..d76dd7d 100644 (file)
@@ -387,10 +387,44 @@ static void arcnet_timer(struct timer_list *t)
        struct arcnet_local *lp = from_timer(lp, t, timer);
        struct net_device *dev = lp->dev;
 
-       if (!netif_carrier_ok(dev)) {
+       spin_lock_irq(&lp->lock);
+
+       if (!lp->reset_in_progress && !netif_carrier_ok(dev)) {
                netif_carrier_on(dev);
                netdev_info(dev, "link up\n");
        }
+
+       spin_unlock_irq(&lp->lock);
+}
+
+static void reset_device_work(struct work_struct *work)
+{
+       struct arcnet_local *lp;
+       struct net_device *dev;
+
+       lp = container_of(work, struct arcnet_local, reset_work);
+       dev = lp->dev;
+
+       /* Do not bring the network interface back up if an ifdown
+        * was already done.
+        */
+       if (!netif_running(dev) || !lp->reset_in_progress)
+               return;
+
+       rtnl_lock();
+
+       /* Do another check, in case of an ifdown that was triggered in
+        * the small race window between the exit condition above and
+        * acquiring RTNL.
+        */
+       if (!netif_running(dev) || !lp->reset_in_progress)
+               goto out;
+
+       dev_close(dev);
+       dev_open(dev, NULL);
+
+out:
+       rtnl_unlock();
 }
 
 static void arcnet_reply_tasklet(unsigned long data)
@@ -452,12 +486,25 @@ struct net_device *alloc_arcdev(const char *name)
                lp->dev = dev;
                spin_lock_init(&lp->lock);
                timer_setup(&lp->timer, arcnet_timer, 0);
+               INIT_WORK(&lp->reset_work, reset_device_work);
        }
 
        return dev;
 }
 EXPORT_SYMBOL(alloc_arcdev);
 
+void free_arcdev(struct net_device *dev)
+{
+       struct arcnet_local *lp = netdev_priv(dev);
+
+       /* Do not cancel this at ->ndo_close(), as the workqueue itself
+        * indirectly calls the ifdown path through dev_close().
+        */
+       cancel_work_sync(&lp->reset_work);
+       free_netdev(dev);
+}
+EXPORT_SYMBOL(free_arcdev);
+
 /* Open/initialize the board.  This is called sometime after booting when
  * the 'ifconfig' program is run.
  *
@@ -587,6 +634,10 @@ int arcnet_close(struct net_device *dev)
 
        /* shut down the card */
        lp->hw.close(dev);
+
+       /* reset counters */
+       lp->reset_in_progress = 0;
+
        module_put(lp->hw.owner);
        return 0;
 }
@@ -820,6 +871,9 @@ irqreturn_t arcnet_interrupt(int irq, void *dev_id)
 
        spin_lock_irqsave(&lp->lock, flags);
 
+       if (lp->reset_in_progress)
+               goto out;
+
        /* RESET flag was enabled - if device is not running, we must
         * clear it right away (but nothing else).
         */
@@ -852,11 +906,14 @@ irqreturn_t arcnet_interrupt(int irq, void *dev_id)
                if (status & RESETflag) {
                        arc_printk(D_NORMAL, dev, "spurious reset (status=%Xh)\n",
                                   status);
-                       arcnet_close(dev);
-                       arcnet_open(dev);
+
+                       lp->reset_in_progress = 1;
+                       netif_stop_queue(dev);
+                       netif_carrier_off(dev);
+                       schedule_work(&lp->reset_work);
 
                        /* get out of the interrupt handler! */
-                       break;
+                       goto out;
                }
                /* RX is inhibited - we must have received something.
                 * Prepare to receive into the next buffer.
@@ -1052,6 +1109,7 @@ irqreturn_t arcnet_interrupt(int irq, void *dev_id)
        udelay(1);
        lp->hw.intmask(dev, lp->intmask);
 
+out:
        spin_unlock_irqrestore(&lp->lock, flags);
        return retval;
 }
index f983c4c..be618e4 100644 (file)
@@ -169,7 +169,7 @@ static int __init com20020_init(void)
                dev->irq = 9;
 
        if (com20020isa_probe(dev)) {
-               free_netdev(dev);
+               free_arcdev(dev);
                return -EIO;
        }
 
@@ -182,7 +182,7 @@ static void __exit com20020_exit(void)
        unregister_netdev(my_dev);
        free_irq(my_dev->irq, my_dev);
        release_region(my_dev->base_addr, ARCNET_TOTAL_SIZE);
-       free_netdev(my_dev);
+       free_arcdev(my_dev);
 }
 
 #ifndef MODULE
index eb7f767..8bdc44b 100644 (file)
@@ -291,7 +291,7 @@ static void com20020pci_remove(struct pci_dev *pdev)
 
                unregister_netdev(dev);
                free_irq(dev->irq, dev);
-               free_netdev(dev);
+               free_arcdev(dev);
        }
 }
 
index cf607ff..9cc5eb6 100644 (file)
@@ -177,7 +177,7 @@ static void com20020_detach(struct pcmcia_device *link)
                dev = info->dev;
                if (dev) {
                        dev_dbg(&link->dev, "kfree...\n");
-                       free_netdev(dev);
+                       free_arcdev(dev);
                }
                dev_dbg(&link->dev, "kfree2...\n");
                kfree(info);
index cf214b7..3856b44 100644 (file)
@@ -396,7 +396,7 @@ static int __init com90io_init(void)
        err = com90io_probe(dev);
 
        if (err) {
-               free_netdev(dev);
+               free_arcdev(dev);
                return err;
        }
 
@@ -419,7 +419,7 @@ static void __exit com90io_exit(void)
 
        free_irq(dev->irq, dev);
        release_region(dev->base_addr, ARCNET_TOTAL_SIZE);
-       free_netdev(dev);
+       free_arcdev(dev);
 }
 
 module_init(com90io_init)
index 3dc3d53..d8dfb9e 100644 (file)
@@ -554,7 +554,7 @@ err_free_irq:
 err_release_mem:
        release_mem_region(dev->mem_start, dev->mem_end - dev->mem_start + 1);
 err_free_dev:
-       free_netdev(dev);
+       free_arcdev(dev);
        return -EIO;
 }
 
@@ -672,7 +672,7 @@ static void __exit com90xx_exit(void)
                release_region(dev->base_addr, ARCNET_TOTAL_SIZE);
                release_mem_region(dev->mem_start,
                                   dev->mem_end - dev->mem_start + 1);
-               free_netdev(dev);
+               free_arcdev(dev);
        }
 }
 
index 6475060..0321be7 100644 (file)
@@ -238,7 +238,6 @@ struct adapter {
        int msg_enable;
        u32 mmio_len;
 
-       struct work_struct ext_intr_handler_task;
        struct adapter_params params;
 
        /* Terminator modules. */
@@ -257,6 +256,7 @@ struct adapter {
 
        /* guards async operations */
        spinlock_t async_lock ____cacheline_aligned;
+       u32 pending_thread_intr;
        u32 slow_intr_mask;
        int t1powersave;
 };
@@ -334,8 +334,7 @@ void t1_interrupts_enable(adapter_t *adapter);
 void t1_interrupts_disable(adapter_t *adapter);
 void t1_interrupts_clear(adapter_t *adapter);
 int t1_elmer0_ext_intr_handler(adapter_t *adapter);
-void t1_elmer0_ext_intr(adapter_t *adapter);
-int t1_slow_intr_handler(adapter_t *adapter);
+irqreturn_t t1_slow_intr_handler(adapter_t *adapter);
 
 int t1_link_start(struct cphy *phy, struct cmac *mac, struct link_config *lc);
 const struct board_info *t1_get_board_info(unsigned int board_id);
@@ -347,7 +346,6 @@ int t1_get_board_rev(adapter_t *adapter, const struct board_info *bi,
 int t1_init_hw_modules(adapter_t *adapter);
 int t1_init_sw_modules(adapter_t *adapter, const struct board_info *bi);
 void t1_free_sw_modules(adapter_t *adapter);
-void t1_fatal_err(adapter_t *adapter);
 void t1_link_changed(adapter_t *adapter, int port_id);
 void t1_link_negotiated(adapter_t *adapter, int port_id, int link_stat,
                            int speed, int duplex, int pause);
index c6db85f..2a28a38 100644 (file)
@@ -211,9 +211,10 @@ static int cxgb_up(struct adapter *adapter)
        t1_interrupts_clear(adapter);
 
        adapter->params.has_msi = !disable_msi && !pci_enable_msi(adapter->pdev);
-       err = request_irq(adapter->pdev->irq, t1_interrupt,
-                         adapter->params.has_msi ? 0 : IRQF_SHARED,
-                         adapter->name, adapter);
+       err = request_threaded_irq(adapter->pdev->irq, t1_interrupt,
+                                  t1_interrupt_thread,
+                                  adapter->params.has_msi ? 0 : IRQF_SHARED,
+                                  adapter->name, adapter);
        if (err) {
                if (adapter->params.has_msi)
                        pci_disable_msi(adapter->pdev);
@@ -916,51 +917,6 @@ static void mac_stats_task(struct work_struct *work)
        spin_unlock(&adapter->work_lock);
 }
 
-/*
- * Processes elmer0 external interrupts in process context.
- */
-static void ext_intr_task(struct work_struct *work)
-{
-       struct adapter *adapter =
-               container_of(work, struct adapter, ext_intr_handler_task);
-
-       t1_elmer0_ext_intr_handler(adapter);
-
-       /* Now reenable external interrupts */
-       spin_lock_irq(&adapter->async_lock);
-       adapter->slow_intr_mask |= F_PL_INTR_EXT;
-       writel(F_PL_INTR_EXT, adapter->regs + A_PL_CAUSE);
-       writel(adapter->slow_intr_mask | F_PL_INTR_SGE_DATA,
-                  adapter->regs + A_PL_ENABLE);
-       spin_unlock_irq(&adapter->async_lock);
-}
-
-/*
- * Interrupt-context handler for elmer0 external interrupts.
- */
-void t1_elmer0_ext_intr(struct adapter *adapter)
-{
-       /*
-        * Schedule a task to handle external interrupts as we require
-        * a process context.  We disable EXT interrupts in the interim
-        * and let the task reenable them when it's done.
-        */
-       adapter->slow_intr_mask &= ~F_PL_INTR_EXT;
-       writel(adapter->slow_intr_mask | F_PL_INTR_SGE_DATA,
-                  adapter->regs + A_PL_ENABLE);
-       schedule_work(&adapter->ext_intr_handler_task);
-}
-
-void t1_fatal_err(struct adapter *adapter)
-{
-       if (adapter->flags & FULL_INIT_DONE) {
-               t1_sge_stop(adapter->sge);
-               t1_interrupts_disable(adapter);
-       }
-       pr_alert("%s: encountered fatal error, operation suspended\n",
-                adapter->name);
-}
-
 static const struct net_device_ops cxgb_netdev_ops = {
        .ndo_open               = cxgb_open,
        .ndo_stop               = cxgb_close,
@@ -1062,8 +1018,6 @@ static int init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
                        spin_lock_init(&adapter->async_lock);
                        spin_lock_init(&adapter->mac_lock);
 
-                       INIT_WORK(&adapter->ext_intr_handler_task,
-                                 ext_intr_task);
                        INIT_DELAYED_WORK(&adapter->stats_update_task,
                                          mac_stats_task);
 
index 2d9c2b5..cda01f2 100644 (file)
@@ -940,10 +940,11 @@ void t1_sge_intr_clear(struct sge *sge)
 /*
  * SGE 'Error' interrupt handler
  */
-int t1_sge_intr_error_handler(struct sge *sge)
+bool t1_sge_intr_error_handler(struct sge *sge)
 {
        struct adapter *adapter = sge->adapter;
        u32 cause = readl(adapter->regs + A_SG_INT_CAUSE);
+       bool wake = false;
 
        if (adapter->port[0].dev->hw_features & NETIF_F_TSO)
                cause &= ~F_PACKET_TOO_BIG;
@@ -967,11 +968,14 @@ int t1_sge_intr_error_handler(struct sge *sge)
                sge->stats.pkt_mismatch++;
                pr_alert("%s: SGE packet mismatch\n", adapter->name);
        }
-       if (cause & SGE_INT_FATAL)
-               t1_fatal_err(adapter);
+       if (cause & SGE_INT_FATAL) {
+               t1_interrupts_disable(adapter);
+               adapter->pending_thread_intr |= F_PL_INTR_SGE_ERR;
+               wake = true;
+       }
 
        writel(cause, adapter->regs + A_SG_INT_CAUSE);
-       return 0;
+       return wake;
 }
 
 const struct sge_intr_counts *t1_sge_get_intr_counts(const struct sge *sge)
@@ -1619,11 +1623,46 @@ int t1_poll(struct napi_struct *napi, int budget)
        return work_done;
 }
 
+irqreturn_t t1_interrupt_thread(int irq, void *data)
+{
+       struct adapter *adapter = data;
+       u32 pending_thread_intr;
+
+       spin_lock_irq(&adapter->async_lock);
+       pending_thread_intr = adapter->pending_thread_intr;
+       adapter->pending_thread_intr = 0;
+       spin_unlock_irq(&adapter->async_lock);
+
+       if (!pending_thread_intr)
+               return IRQ_NONE;
+
+       if (pending_thread_intr & F_PL_INTR_EXT)
+               t1_elmer0_ext_intr_handler(adapter);
+
+       /* This error is fatal, interrupts remain off */
+       if (pending_thread_intr & F_PL_INTR_SGE_ERR) {
+               pr_alert("%s: encountered fatal error, operation suspended\n",
+                        adapter->name);
+               t1_sge_stop(adapter->sge);
+               return IRQ_HANDLED;
+       }
+
+       spin_lock_irq(&adapter->async_lock);
+       adapter->slow_intr_mask |= F_PL_INTR_EXT;
+
+       writel(F_PL_INTR_EXT, adapter->regs + A_PL_CAUSE);
+       writel(adapter->slow_intr_mask | F_PL_INTR_SGE_DATA,
+              adapter->regs + A_PL_ENABLE);
+       spin_unlock_irq(&adapter->async_lock);
+
+       return IRQ_HANDLED;
+}
+
 irqreturn_t t1_interrupt(int irq, void *data)
 {
        struct adapter *adapter = data;
        struct sge *sge = adapter->sge;
-       int handled;
+       irqreturn_t handled;
 
        if (likely(responses_pending(adapter))) {
                writel(F_PL_INTR_SGE_DATA, adapter->regs + A_PL_CAUSE);
@@ -1645,10 +1684,10 @@ irqreturn_t t1_interrupt(int irq, void *data)
        handled = t1_slow_intr_handler(adapter);
        spin_unlock(&adapter->async_lock);
 
-       if (!handled)
+       if (handled == IRQ_NONE)
                sge->stats.unhandled_irqs++;
 
-       return IRQ_RETVAL(handled != 0);
+       return handled;
 }
 
 /*
index a1ba591..716705b 100644 (file)
@@ -74,6 +74,7 @@ struct sge *t1_sge_create(struct adapter *, struct sge_params *);
 int t1_sge_configure(struct sge *, struct sge_params *);
 int t1_sge_set_coalesce_params(struct sge *, struct sge_params *);
 void t1_sge_destroy(struct sge *);
+irqreturn_t t1_interrupt_thread(int irq, void *data);
 irqreturn_t t1_interrupt(int irq, void *cookie);
 int t1_poll(struct napi_struct *, int);
 
@@ -81,7 +82,7 @@ netdev_tx_t t1_start_xmit(struct sk_buff *skb, struct net_device *dev);
 void t1_vlan_mode(struct adapter *adapter, netdev_features_t features);
 void t1_sge_start(struct sge *);
 void t1_sge_stop(struct sge *);
-int t1_sge_intr_error_handler(struct sge *);
+bool t1_sge_intr_error_handler(struct sge *sge);
 void t1_sge_intr_enable(struct sge *);
 void t1_sge_intr_disable(struct sge *);
 void t1_sge_intr_clear(struct sge *);
index ea0f874..310add2 100644 (file)
@@ -170,7 +170,7 @@ void t1_link_changed(adapter_t *adapter, int port_id)
        t1_link_negotiated(adapter, port_id, link_ok, speed, duplex, fc);
 }
 
-static int t1_pci_intr_handler(adapter_t *adapter)
+static bool t1_pci_intr_handler(adapter_t *adapter)
 {
        u32 pcix_cause;
 
@@ -179,9 +179,13 @@ static int t1_pci_intr_handler(adapter_t *adapter)
        if (pcix_cause) {
                pci_write_config_dword(adapter->pdev, A_PCICFG_INTR_CAUSE,
                                       pcix_cause);
-               t1_fatal_err(adapter);    /* PCI errors are fatal */
+               /* PCI errors are fatal */
+               t1_interrupts_disable(adapter);
+               adapter->pending_thread_intr |= F_PL_INTR_SGE_ERR;
+               pr_alert("%s: PCI error encountered.\n", adapter->name);
+               return true;
        }
-       return 0;
+       return false;
 }
 
 #ifdef CONFIG_CHELSIO_T1_1G
@@ -210,13 +214,16 @@ static int fpga_phy_intr_handler(adapter_t *adapter)
 /*
  * Slow path interrupt handler for FPGAs.
  */
-static int fpga_slow_intr(adapter_t *adapter)
+static irqreturn_t fpga_slow_intr(adapter_t *adapter)
 {
        u32 cause = readl(adapter->regs + A_PL_CAUSE);
+       irqreturn_t ret = IRQ_NONE;
 
        cause &= ~F_PL_INTR_SGE_DATA;
-       if (cause & F_PL_INTR_SGE_ERR)
-               t1_sge_intr_error_handler(adapter->sge);
+       if (cause & F_PL_INTR_SGE_ERR) {
+               if (t1_sge_intr_error_handler(adapter->sge))
+                       ret = IRQ_WAKE_THREAD;
+       }
 
        if (cause & FPGA_PCIX_INTERRUPT_GMAC)
                fpga_phy_intr_handler(adapter);
@@ -231,14 +238,19 @@ static int fpga_slow_intr(adapter_t *adapter)
                /* Clear TP interrupt */
                writel(tp_cause, adapter->regs + FPGA_TP_ADDR_INTERRUPT_CAUSE);
        }
-       if (cause & FPGA_PCIX_INTERRUPT_PCIX)
-               t1_pci_intr_handler(adapter);
+       if (cause & FPGA_PCIX_INTERRUPT_PCIX) {
+               if (t1_pci_intr_handler(adapter))
+                       ret = IRQ_WAKE_THREAD;
+       }
 
        /* Clear the interrupts just processed. */
        if (cause)
                writel(cause, adapter->regs + A_PL_CAUSE);
 
-       return cause != 0;
+       if (ret != IRQ_NONE)
+               return ret;
+
+       return cause == 0 ? IRQ_NONE : IRQ_HANDLED;
 }
 #endif
 
@@ -842,31 +854,45 @@ void t1_interrupts_clear(adapter_t* adapter)
 /*
  * Slow path interrupt handler for ASICs.
  */
-static int asic_slow_intr(adapter_t *adapter)
+static irqreturn_t asic_slow_intr(adapter_t *adapter)
 {
        u32 cause = readl(adapter->regs + A_PL_CAUSE);
+       irqreturn_t ret = IRQ_HANDLED;
 
        cause &= adapter->slow_intr_mask;
        if (!cause)
-               return 0;
-       if (cause & F_PL_INTR_SGE_ERR)
-               t1_sge_intr_error_handler(adapter->sge);
+               return IRQ_NONE;
+       if (cause & F_PL_INTR_SGE_ERR) {
+               if (t1_sge_intr_error_handler(adapter->sge))
+                       ret = IRQ_WAKE_THREAD;
+       }
        if (cause & F_PL_INTR_TP)
                t1_tp_intr_handler(adapter->tp);
        if (cause & F_PL_INTR_ESPI)
                t1_espi_intr_handler(adapter->espi);
-       if (cause & F_PL_INTR_PCIX)
-               t1_pci_intr_handler(adapter);
-       if (cause & F_PL_INTR_EXT)
-               t1_elmer0_ext_intr(adapter);
+       if (cause & F_PL_INTR_PCIX) {
+               if (t1_pci_intr_handler(adapter))
+                       ret = IRQ_WAKE_THREAD;
+       }
+       if (cause & F_PL_INTR_EXT) {
+               /* Wake the threaded interrupt to handle external interrupts as
+                * we require a process context. We disable EXT interrupts in
+                * the interim and let the thread reenable them when it's done.
+                */
+               adapter->pending_thread_intr |= F_PL_INTR_EXT;
+               adapter->slow_intr_mask &= ~F_PL_INTR_EXT;
+               writel(adapter->slow_intr_mask | F_PL_INTR_SGE_DATA,
+                      adapter->regs + A_PL_ENABLE);
+               ret = IRQ_WAKE_THREAD;
+       }
 
        /* Clear the interrupts just processed. */
        writel(cause, adapter->regs + A_PL_CAUSE);
        readl(adapter->regs + A_PL_CAUSE); /* flush writes */
-       return 1;
+       return ret;
 }
 
-int t1_slow_intr_handler(adapter_t *adapter)
+irqreturn_t t1_slow_intr_handler(adapter_t *adapter)
 {
 #ifdef CONFIG_CHELSIO_T1_1G
        if (!t1_is_asic(adapter))
index e3a8858..df0eab4 100644 (file)
@@ -963,7 +963,7 @@ static void tx_timeout(struct net_device *dev, unsigned int txqueue)
        unsigned long flag;
 
        netif_stop_queue(dev);
-       tasklet_disable(&np->tx_tasklet);
+       tasklet_disable_in_atomic(&np->tx_tasklet);
        iowrite16(0, ioaddr + IntrEnable);
        printk(KERN_WARNING "%s: Transmit timed out, TxStatus %2.2x "
                   "TxFrameId %2.2x,"
index e9efe07..f1b9284 100644 (file)
@@ -1265,9 +1265,9 @@ jme_stop_shutdown_timer(struct jme_adapter *jme)
        jwrite32f(jme, JME_APMC, apmc);
 }
 
-static void jme_link_change_tasklet(struct tasklet_struct *t)
+static void jme_link_change_work(struct work_struct *work)
 {
-       struct jme_adapter *jme = from_tasklet(jme, t, linkch_task);
+       struct jme_adapter *jme = container_of(work, struct jme_adapter, linkch_task);
        struct net_device *netdev = jme->dev;
        int rc;
 
@@ -1510,7 +1510,7 @@ jme_intr_msi(struct jme_adapter *jme, u32 intrstat)
                 * all other events are ignored
                 */
                jwrite32(jme, JME_IEVE, intrstat);
-               tasklet_schedule(&jme->linkch_task);
+               schedule_work(&jme->linkch_task);
                goto out_reenable;
        }
 
@@ -1832,7 +1832,6 @@ jme_open(struct net_device *netdev)
        jme_clear_pm_disable_wol(jme);
        JME_NAPI_ENABLE(jme);
 
-       tasklet_setup(&jme->linkch_task, jme_link_change_tasklet);
        tasklet_setup(&jme->txclean_task, jme_tx_clean_tasklet);
        tasklet_setup(&jme->rxclean_task, jme_rx_clean_tasklet);
        tasklet_setup(&jme->rxempty_task, jme_rx_empty_tasklet);
@@ -1920,7 +1919,7 @@ jme_close(struct net_device *netdev)
 
        JME_NAPI_DISABLE(jme);
 
-       tasklet_kill(&jme->linkch_task);
+       cancel_work_sync(&jme->linkch_task);
        tasklet_kill(&jme->txclean_task);
        tasklet_kill(&jme->rxclean_task);
        tasklet_kill(&jme->rxempty_task);
@@ -3035,6 +3034,7 @@ jme_init_one(struct pci_dev *pdev,
        atomic_set(&jme->rx_empty, 1);
 
        tasklet_setup(&jme->pcc_task, jme_pcc_tasklet);
+       INIT_WORK(&jme->linkch_task, jme_link_change_work);
        jme->dpi.cur = PCC_P1;
 
        jme->reg_ghc = 0;
index a2c3b00..2af7632 100644 (file)
@@ -411,7 +411,7 @@ struct jme_adapter {
        struct tasklet_struct   rxempty_task;
        struct tasklet_struct   rxclean_task;
        struct tasklet_struct   txclean_task;
-       struct tasklet_struct   linkch_task;
+       struct work_struct      linkch_task;
        struct tasklet_struct   pcc_task;
        unsigned long           flags;
        u32                     reg_txcs;
index 71e2ada..72e2e71 100644 (file)
@@ -251,7 +251,7 @@ void ath9k_beacon_ensure_primary_slot(struct ath_softc *sc)
        int first_slot = ATH_BCBUF;
        int slot;
 
-       tasklet_disable(&sc->bcon_tasklet);
+       tasklet_disable_in_atomic(&sc->bcon_tasklet);
 
        /* Find first taken slot. */
        for (slot = 0; slot < ATH_BCBUF; slot++) {
index ad3e3cd..c0b8911 100644 (file)
@@ -1457,7 +1457,7 @@ static void hv_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
         * Prevents hv_pci_onchannelcallback() from running concurrently
         * in the tasklet.
         */
-       tasklet_disable(&channel->callback_event);
+       tasklet_disable_in_atomic(&channel->callback_event);
 
        /*
         * Since this function is called with IRQ locks held, can't
index 0f92749..dc97e4f 100644 (file)
@@ -1452,11 +1452,11 @@ 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;
 }
@@ -1641,11 +1641,11 @@ 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;
 }
 
@@ -1686,7 +1686,7 @@ 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 "
@@ -1718,13 +1718,13 @@ 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 5ea426e..0d6b9ac 100644 (file)
@@ -828,7 +828,7 @@ 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;
@@ -864,7 +864,7 @@ 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 a50f1ee..0b2acad 100644 (file)
@@ -826,10 +826,10 @@ 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 34aa271..42cd2ba 100644 (file)
@@ -131,12 +131,55 @@ static inline void serial_dl_write(struct uart_8250_port *up, int value)
        up->dl_write(up, value);
 }
 
+static inline void serial8250_set_IER(struct uart_8250_port *up,
+                                     unsigned char ier)
+{
+       struct uart_port *port = &up->port;
+       unsigned int flags;
+       bool is_console;
+
+       is_console = uart_console(port);
+
+       if (is_console)
+               console_atomic_lock(&flags);
+
+       serial_out(up, UART_IER, ier);
+
+       if (is_console)
+               console_atomic_unlock(flags);
+}
+
+static inline unsigned char serial8250_clear_IER(struct uart_8250_port *up)
+{
+       struct uart_port *port = &up->port;
+       unsigned int clearval = 0;
+       unsigned int prior;
+       unsigned int flags;
+       bool is_console;
+
+       is_console = uart_console(port);
+
+       if (up->capabilities & UART_CAP_UUE)
+               clearval = UART_IER_UUE;
+
+       if (is_console)
+               console_atomic_lock(&flags);
+
+       prior = serial_port_in(port, UART_IER);
+       serial_port_out(port, UART_IER, clearval);
+
+       if (is_console)
+               console_atomic_unlock(flags);
+
+       return prior;
+}
+
 static inline bool serial8250_set_THRI(struct uart_8250_port *up)
 {
        if (up->ier & UART_IER_THRI)
                return false;
        up->ier |= UART_IER_THRI;
-       serial_out(up, UART_IER, up->ier);
+       serial8250_set_IER(up, up->ier);
        return true;
 }
 
@@ -145,7 +188,7 @@ static inline bool serial8250_clear_THRI(struct uart_8250_port *up)
        if (!(up->ier & UART_IER_THRI))
                return false;
        up->ier &= ~UART_IER_THRI;
-       serial_out(up, UART_IER, up->ier);
+       serial8250_set_IER(up, up->ier);
        return true;
 }
 
index cae61d1..47dd230 100644 (file)
@@ -274,10 +274,8 @@ static void serial8250_backup_timeout(struct timer_list *t)
         * Must disable interrupts or else we risk racing with the interrupt
         * based handler.
         */
-       if (up->port.irq) {
-               ier = serial_in(up, UART_IER);
-               serial_out(up, UART_IER, 0);
-       }
+       if (up->port.irq)
+               ier = serial8250_clear_IER(up);
 
        iir = serial_in(up, UART_IIR);
 
@@ -300,7 +298,7 @@ static void serial8250_backup_timeout(struct timer_list *t)
                serial8250_tx_chars(up);
 
        if (up->port.irq)
-               serial_out(up, UART_IER, ier);
+               serial8250_set_IER(up, ier);
 
        spin_unlock_irqrestore(&up->port.lock, flags);
 
@@ -578,6 +576,14 @@ serial8250_register_ports(struct uart_driver *drv, struct device *dev)
 
 #ifdef CONFIG_SERIAL_8250_CONSOLE
 
+static void univ8250_console_write_atomic(struct console *co, const char *s,
+                                         unsigned int count)
+{
+       struct uart_8250_port *up = &serial8250_ports[co->index];
+
+       serial8250_console_write_atomic(up, s, count);
+}
+
 static void univ8250_console_write(struct console *co, const char *s,
                                   unsigned int count)
 {
@@ -671,6 +677,7 @@ static int univ8250_console_match(struct console *co, char *name, int idx,
 
 static struct console univ8250_console = {
        .name           = "ttyS",
+       .write_atomic   = univ8250_console_write_atomic,
        .write          = univ8250_console_write,
        .device         = uart_console_device,
        .setup          = univ8250_console_setup,
index fbcc90c..b33cb45 100644 (file)
@@ -60,9 +60,18 @@ int fsl8250_handle_irq(struct uart_port *port)
 
        /* Stop processing interrupts on input overrun */
        if ((orig_lsr & UART_LSR_OE) && (up->overrun_backoff_time_ms > 0)) {
+               unsigned int ca_flags;
                unsigned long delay;
+               bool is_console;
 
+               is_console = uart_console(port);
+
+               if (is_console)
+                       console_atomic_lock(&ca_flags);
                up->ier = port->serial_in(port, UART_IER);
+               if (is_console)
+                       console_atomic_unlock(ca_flags);
+
                if (up->ier & (UART_IER_RLSI | UART_IER_RDI)) {
                        port->ops->stop_rx(port);
                } else {
index 988bf6b..bcd26d6 100644 (file)
@@ -146,6 +146,8 @@ OF_EARLYCON_DECLARE(x1000_uart, "ingenic,x1000-uart",
 
 static void ingenic_uart_serial_out(struct uart_port *p, int offset, int value)
 {
+       unsigned int flags;
+       bool is_console;
        int ier;
 
        switch (offset) {
@@ -167,7 +169,12 @@ static void ingenic_uart_serial_out(struct uart_port *p, int offset, int value)
                 * If we have enabled modem status IRQs we should enable
                 * modem mode.
                 */
+               is_console = uart_console(p);
+               if (is_console)
+                       console_atomic_lock(&flags);
                ier = p->serial_in(p, UART_IER);
+               if (is_console)
+                       console_atomic_unlock(flags);
 
                if (ier & UART_IER_MSI)
                        value |= UART_MCR_MDCE | UART_MCR_FCM;
index fb65dc6..5bc734c 100644 (file)
@@ -218,12 +218,37 @@ static void mtk8250_shutdown(struct uart_port *port)
 
 static void mtk8250_disable_intrs(struct uart_8250_port *up, int mask)
 {
-       serial_out(up, UART_IER, serial_in(up, UART_IER) & (~mask));
+       struct uart_port *port = &up->port;
+       unsigned int flags;
+       unsigned int ier;
+       bool is_console;
+
+       is_console = uart_console(port);
+
+       if (is_console)
+               console_atomic_lock(&flags);
+
+       ier = serial_in(up, UART_IER);
+       serial_out(up, UART_IER, ier & (~mask));
+
+       if (is_console)
+               console_atomic_unlock(flags);
 }
 
 static void mtk8250_enable_intrs(struct uart_8250_port *up, int mask)
 {
-       serial_out(up, UART_IER, serial_in(up, UART_IER) | mask);
+       struct uart_port *port = &up->port;
+       unsigned int flags;
+       unsigned int ier;
+
+       if (uart_console(port))
+               console_atomic_lock(&flags);
+
+       ier = serial_in(up, UART_IER);
+       serial_out(up, UART_IER, ier | mask);
+
+       if (uart_console(port))
+               console_atomic_unlock(flags);
 }
 
 static void mtk8250_set_flow_ctrl(struct uart_8250_port *up, int mode)
index 7c07ebb..a0a617c 100644 (file)
@@ -762,7 +762,7 @@ static void serial8250_set_sleep(struct uart_8250_port *p, int sleep)
                        serial_out(p, UART_EFR, UART_EFR_ECB);
                        serial_out(p, UART_LCR, 0);
                }
-               serial_out(p, UART_IER, sleep ? UART_IERX_SLEEP : 0);
+               serial8250_set_IER(p, sleep ? UART_IERX_SLEEP : 0);
                if (p->capabilities & UART_CAP_EFR) {
                        serial_out(p, UART_LCR, UART_LCR_CONF_MODE_B);
                        serial_out(p, UART_EFR, efr);
@@ -1436,7 +1436,7 @@ static void serial8250_stop_rx(struct uart_port *port)
 
        up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
        up->port.read_status_mask &= ~UART_LSR_DR;
-       serial_port_out(port, UART_IER, up->ier);
+       serial8250_set_IER(up, up->ier);
 
        serial8250_rpm_put(up);
 }
@@ -1466,7 +1466,7 @@ void serial8250_em485_stop_tx(struct uart_8250_port *p)
                serial8250_clear_and_reinit_fifos(p);
 
                p->ier |= UART_IER_RLSI | UART_IER_RDI;
-               serial_port_out(&p->port, UART_IER, p->ier);
+               serial8250_set_IER(p, p->ier);
        }
 }
 EXPORT_SYMBOL_GPL(serial8250_em485_stop_tx);
@@ -1694,7 +1694,7 @@ static void serial8250_disable_ms(struct uart_port *port)
        mctrl_gpio_disable_ms(up->gpios);
 
        up->ier &= ~UART_IER_MSI;
-       serial_port_out(port, UART_IER, up->ier);
+       serial8250_set_IER(up, up->ier);
 }
 
 static void serial8250_enable_ms(struct uart_port *port)
@@ -1710,7 +1710,7 @@ static void serial8250_enable_ms(struct uart_port *port)
        up->ier |= UART_IER_MSI;
 
        serial8250_rpm_get(up);
-       serial_port_out(port, UART_IER, up->ier);
+       serial8250_set_IER(up, up->ier);
        serial8250_rpm_put(up);
 }
 
@@ -2130,14 +2130,7 @@ static void serial8250_put_poll_char(struct uart_port *port,
        struct uart_8250_port *up = up_to_u8250p(port);
 
        serial8250_rpm_get(up);
-       /*
-        *      First save the IER then disable the interrupts
-        */
-       ier = serial_port_in(port, UART_IER);
-       if (up->capabilities & UART_CAP_UUE)
-               serial_port_out(port, UART_IER, UART_IER_UUE);
-       else
-               serial_port_out(port, UART_IER, 0);
+       ier = serial8250_clear_IER(up);
 
        wait_for_xmitr(up, BOTH_EMPTY);
        /*
@@ -2150,7 +2143,7 @@ static void serial8250_put_poll_char(struct uart_port *port,
         *      and restore the IER
         */
        wait_for_xmitr(up, BOTH_EMPTY);
-       serial_port_out(port, UART_IER, ier);
+       serial8250_set_IER(up, ier);
        serial8250_rpm_put(up);
 }
 
@@ -2453,7 +2446,7 @@ void serial8250_do_shutdown(struct uart_port *port)
         */
        spin_lock_irqsave(&port->lock, flags);
        up->ier = 0;
-       serial_port_out(port, UART_IER, 0);
+       serial8250_set_IER(up, 0);
        spin_unlock_irqrestore(&port->lock, flags);
 
        synchronize_irq(port->irq);
@@ -2809,7 +2802,7 @@ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios,
        if (up->capabilities & UART_CAP_RTOIE)
                up->ier |= UART_IER_RTOIE;
 
-       serial_port_out(port, UART_IER, up->ier);
+       serial8250_set_IER(up, up->ier);
 
        if (up->capabilities & UART_CAP_EFR) {
                unsigned char efr = 0;
@@ -3275,7 +3268,7 @@ EXPORT_SYMBOL_GPL(serial8250_set_defaults);
 
 #ifdef CONFIG_SERIAL_8250_CONSOLE
 
-static void serial8250_console_putchar(struct uart_port *port, int ch)
+static void serial8250_console_putchar_locked(struct uart_port *port, int ch)
 {
        struct uart_8250_port *up = up_to_u8250p(port);
 
@@ -3283,6 +3276,18 @@ static void serial8250_console_putchar(struct uart_port *port, int ch)
        serial_port_out(port, UART_TX, ch);
 }
 
+static void serial8250_console_putchar(struct uart_port *port, int ch)
+{
+       struct uart_8250_port *up = up_to_u8250p(port);
+       unsigned int flags;
+
+       wait_for_xmitr(up, UART_LSR_THRE);
+
+       console_atomic_lock(&flags);
+       serial8250_console_putchar_locked(port, ch);
+       console_atomic_unlock(flags);
+}
+
 /*
  *     Restore serial console when h/w power-off detected
  */
@@ -3304,6 +3309,32 @@ static void serial8250_console_restore(struct uart_8250_port *up)
        serial8250_out_MCR(up, UART_MCR_DTR | UART_MCR_RTS);
 }
 
+void serial8250_console_write_atomic(struct uart_8250_port *up,
+                                    const char *s, unsigned int count)
+{
+       struct uart_port *port = &up->port;
+       unsigned int flags;
+       unsigned int ier;
+
+       console_atomic_lock(&flags);
+
+       touch_nmi_watchdog();
+
+       ier = serial8250_clear_IER(up);
+
+       if (atomic_fetch_inc(&up->console_printing)) {
+               uart_console_write(port, "\n", 1,
+                                  serial8250_console_putchar_locked);
+       }
+       uart_console_write(port, s, count, serial8250_console_putchar_locked);
+       atomic_dec(&up->console_printing);
+
+       wait_for_xmitr(up, BOTH_EMPTY);
+       serial8250_set_IER(up, ier);
+
+       console_atomic_unlock(flags);
+}
+
 /*
  *     Print a string to the serial port trying not to disturb
  *     any possible real use of the port...
@@ -3320,24 +3351,12 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
        struct uart_port *port = &up->port;
        unsigned long flags;
        unsigned int ier;
-       int locked = 1;
 
        touch_nmi_watchdog();
 
-       if (oops_in_progress)
-               locked = spin_trylock_irqsave(&port->lock, flags);
-       else
-               spin_lock_irqsave(&port->lock, flags);
-
-       /*
-        *      First save the IER then disable the interrupts
-        */
-       ier = serial_port_in(port, UART_IER);
+       spin_lock_irqsave(&port->lock, flags);
 
-       if (up->capabilities & UART_CAP_UUE)
-               serial_port_out(port, UART_IER, UART_IER_UUE);
-       else
-               serial_port_out(port, UART_IER, 0);
+       ier = serial8250_clear_IER(up);
 
        /* check scratch reg to see if port powered off during system sleep */
        if (up->canary && (up->canary != serial_port_in(port, UART_SCR))) {
@@ -3351,7 +3370,9 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
                mdelay(port->rs485.delay_rts_before_send);
        }
 
+       atomic_inc(&up->console_printing);
        uart_console_write(port, s, count, serial8250_console_putchar);
+       atomic_dec(&up->console_printing);
 
        /*
         *      Finally, wait for transmitter to become empty
@@ -3364,8 +3385,7 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
                if (em485->tx_stopped)
                        up->rs485_stop_tx(up);
        }
-
-       serial_port_out(port, UART_IER, ier);
+       serial8250_set_IER(up, ier);
 
        /*
         *      The receive handling will happen properly because the
@@ -3377,8 +3397,7 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
        if (up->msr_saved_flags)
                serial8250_modem_status(up);
 
-       if (locked)
-               spin_unlock_irqrestore(&port->lock, flags);
+       spin_unlock_irqrestore(&port->lock, flags);
 }
 
 static unsigned int probe_baud(struct uart_port *port)
@@ -3398,6 +3417,7 @@ static unsigned int probe_baud(struct uart_port *port)
 
 int serial8250_console_setup(struct uart_port *port, char *options, bool probe)
 {
+       struct uart_8250_port *up = up_to_u8250p(port);
        int baud = 9600;
        int bits = 8;
        int parity = 'n';
@@ -3407,6 +3427,8 @@ int serial8250_console_setup(struct uart_port *port, char *options, bool probe)
        if (!port->iobase && !port->membase)
                return -ENODEV;
 
+       atomic_set(&up->console_printing, 0);
+
        if (options)
                uart_parse_options(options, &baud, &parity, &bits, &flow);
        else if (probe)
index 8e45195..7c8906f 100644 (file)
@@ -2235,18 +2235,24 @@ pl011_console_write(struct console *co, const char *s, unsigned int count)
 {
        struct uart_amba_port *uap = amba_ports[co->index];
        unsigned int old_cr = 0, new_cr;
-       unsigned long flags;
+       unsigned long flags = 0;
        int locked = 1;
 
        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
@@ -2272,8 +2278,7 @@ 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 84e8158..342005e 100644 (file)
@@ -1311,13 +1311,10 @@ 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
@@ -1346,8 +1343,7 @@ 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 dae9a57..9a6a0ec 100644 (file)
@@ -239,7 +239,7 @@ int afs_silly_iput(struct dentry *dentry, struct inode *inode)
        struct dentry *alias;
        int ret;
 
-       DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+       DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
 
        _enter("%p{%pd},%llx", dentry, dentry, vnode->fid.vnode);
 
index 2a9dfa5..1a78979 100644 (file)
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -43,7 +43,6 @@
 #include <linux/mount.h>
 #include <linux/pseudo_fs.h>
 
-#include <asm/kmap_types.h>
 #include <linux/uaccess.h>
 #include <linux/nospec.h>
 
@@ -1762,7 +1761,7 @@ static int aio_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
                list_del_init(&req->wait.entry);
                list_del(&iocb->ki_list);
                iocb->ki_res.res = mangle_poll(mask);
-               if (iocb->ki_eventfd && eventfd_signal_count()) {
+               if (iocb->ki_eventfd && !eventfd_signal_allowed()) {
                        iocb = NULL;
                        INIT_WORK(&req->work, aio_poll_put_work);
                        schedule_work(&req->work);
index bcc6848..fabbf6c 100644 (file)
@@ -17,7 +17,6 @@
 #include <linux/wait.h>
 #include <linux/slab.h>
 #include <trace/events/btrfs.h>
-#include <asm/kmap_types.h>
 #include <asm/unaligned.h>
 #include <linux/pagemap.h>
 #include <linux/btrfs.h>
index 799be3a..d5165a7 100644 (file)
@@ -81,7 +81,7 @@ 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 ea04858..26a187a 100644 (file)
@@ -2503,9 +2503,10 @@ 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();
        }
@@ -2513,26 +2514,30 @@ 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_exclusive(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);
@@ -2546,7 +2551,7 @@ 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)) {
@@ -2574,7 +2579,7 @@ 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;
@@ -2647,7 +2652,7 @@ 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);
index df466ef..9035ca6 100644 (file)
@@ -25,8 +25,6 @@
 #include <linux/idr.h>
 #include <linux/uio.h>
 
-DEFINE_PER_CPU(int, eventfd_wake_count);
-
 static DEFINE_IDA(eventfd_ida);
 
 struct eventfd_ctx {
@@ -67,21 +65,21 @@ __u64 eventfd_signal(struct eventfd_ctx *ctx, __u64 n)
         * Deadlock or stack overflow issues can happen if we recurse here
         * through waitqueue wakeup handlers. If the caller users potentially
         * nested waitqueues with custom wakeup handlers, then it should
-        * check eventfd_signal_count() before calling this function. If
-        * it returns true, the eventfd_signal() call should be deferred to a
+        * check eventfd_signal_allowed() before calling this function. If
+        * it returns false, the eventfd_signal() call should be deferred to a
         * safe context.
         */
-       if (WARN_ON_ONCE(this_cpu_read(eventfd_wake_count)))
+       if (WARN_ON_ONCE(current->in_eventfd_signal))
                return 0;
 
        spin_lock_irqsave(&ctx->wqh.lock, flags);
-       this_cpu_inc(eventfd_wake_count);
+       current->in_eventfd_signal = 1;
        if (ULLONG_MAX - ctx->count < n)
                n = ULLONG_MAX - ctx->count;
        ctx->count += n;
        if (waitqueue_active(&ctx->wqh))
                wake_up_locked_poll(&ctx->wqh, EPOLLIN);
-       this_cpu_dec(eventfd_wake_count);
+       current->in_eventfd_signal = 0;
        spin_unlock_irqrestore(&ctx->wqh.lock, flags);
 
        return n;
index 64aa552..7dae569 100644 (file)
@@ -95,7 +95,6 @@ extern unsigned fscache_debug;
 extern struct kobject *fscache_root;
 extern struct workqueue_struct *fscache_object_wq;
 extern struct workqueue_struct *fscache_op_wq;
-DECLARE_PER_CPU(wait_queue_head_t, fscache_object_cong_wait);
 
 extern unsigned int fscache_hash(unsigned int salt, unsigned int *data, unsigned int n);
 
index 4207f98..85f8cf3 100644 (file)
@@ -41,8 +41,6 @@ struct kobject *fscache_root;
 struct workqueue_struct *fscache_object_wq;
 struct workqueue_struct *fscache_op_wq;
 
-DEFINE_PER_CPU(wait_queue_head_t, fscache_object_cong_wait);
-
 /* these values serve as lower bounds, will be adjusted in fscache_init() */
 static unsigned fscache_object_max_active = 4;
 static unsigned fscache_op_max_active = 2;
@@ -138,7 +136,6 @@ unsigned int fscache_hash(unsigned int salt, unsigned int *data, unsigned int n)
 static int __init fscache_init(void)
 {
        unsigned int nr_cpus = num_possible_cpus();
-       unsigned int cpu;
        int ret;
 
        fscache_object_max_active =
@@ -161,9 +158,6 @@ static int __init fscache_init(void)
        if (!fscache_op_wq)
                goto error_op_wq;
 
-       for_each_possible_cpu(cpu)
-               init_waitqueue_head(&per_cpu(fscache_object_cong_wait, cpu));
-
        ret = fscache_proc_init();
        if (ret < 0)
                goto error_proc;
index cb2146e..fb9794d 100644 (file)
@@ -807,6 +807,8 @@ void fscache_object_destroy(struct fscache_object *object)
 }
 EXPORT_SYMBOL(fscache_object_destroy);
 
+static DECLARE_WAIT_QUEUE_HEAD(fscache_object_cong_wait);
+
 /*
  * enqueue an object for metadata-type processing
  */
@@ -815,16 +817,12 @@ void fscache_enqueue_object(struct fscache_object *object)
        _enter("{OBJ%x}", object->debug_id);
 
        if (fscache_get_object(object, fscache_obj_get_queue) >= 0) {
-               wait_queue_head_t *cong_wq =
-                       &get_cpu_var(fscache_object_cong_wait);
 
                if (queue_work(fscache_object_wq, &object->work)) {
                        if (fscache_object_congested())
-                               wake_up(cong_wq);
+                               wake_up(&fscache_object_cong_wait);
                } else
                        fscache_put_object(object, fscache_obj_put_queue);
-
-               put_cpu_var(fscache_object_cong_wait);
        }
 }
 
@@ -842,16 +840,15 @@ void fscache_enqueue_object(struct fscache_object *object)
  */
 bool fscache_object_sleep_till_congested(signed long *timeoutp)
 {
-       wait_queue_head_t *cong_wq = this_cpu_ptr(&fscache_object_cong_wait);
        DEFINE_WAIT(wait);
 
        if (fscache_object_congested())
                return true;
 
-       add_wait_queue_exclusive(cong_wq, &wait);
+       add_wait_queue_exclusive(&fscache_object_cong_wait, &wait);
        if (!fscache_object_congested())
                *timeoutp = schedule_timeout(*timeoutp);
-       finish_wait(cong_wq, &wait);
+       finish_wait(&fscache_object_cong_wait, &wait);
 
        return fscache_object_congested();
 }
index bc26783..3176913 100644 (file)
@@ -158,7 +158,7 @@ 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 638d5d5..7477cf8 100644 (file)
@@ -158,7 +158,7 @@ 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 4c9d0c3..5a6e15a 100644 (file)
@@ -1520,7 +1520,7 @@ static struct dentry *__lookup_slow(const struct qstr *name,
 {
        struct dentry *dentry, *old;
        struct inode *inode = dir->d_inode;
-       DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+       DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq);
 
        /* Don't go there if it's already dead */
        if (unlikely(IS_DEADDIR(inode)))
@@ -3014,7 +3014,7 @@ static struct dentry *lookup_open(struct nameidata *nd, struct file *file,
        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 ERR_PTR(-ENOENT);
index ee120e4..2ee15b6 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/cred.h>
 #include <linux/idr.h>
@@ -321,8 +322,11 @@ int __mnt_want_write(struct vfsmount *m)
         * incremented count after it has set MNT_WRITE_HOLD.
         */
        smp_mb();
-       while (READ_ONCE(mnt->mnt.mnt_flags) & MNT_WRITE_HOLD)
-               cpu_relax();
+       while (READ_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 8b963c7..d3981c1 100644 (file)
@@ -484,7 +484,7 @@ void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry,
                unsigned long dir_verifier)
 {
        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 *inode;
@@ -1670,7 +1670,7 @@ int nfs_atomic_open(struct inode *dir, struct dentry *dentry,
                    struct file *file, unsigned open_flags,
                    umode_t mode)
 {
-       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 };
index b27ebdc..f86c98a 100644 (file)
@@ -13,7 +13,7 @@
 #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>
 
@@ -180,7 +180,7 @@ nfs_async_unlink(struct dentry *dentry, const struct qstr *name)
 
        data->cred = get_current_cred();
        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 18a4588..decaa77 100644 (file)
@@ -384,9 +384,9 @@ static inline void task_context_switch_counts(struct seq_file *m,
 static void task_cpus_allowed(struct seq_file *m, struct task_struct *task)
 {
        seq_printf(m, "Cpus_allowed:\t%*pb\n",
-                  cpumask_pr_args(task->cpus_ptr));
+                  cpumask_pr_args(&task->cpus_mask));
        seq_printf(m, "Cpus_allowed_list:\t%*pbl\n",
-                  cpumask_pr_args(task->cpus_ptr));
+                  cpumask_pr_args(&task->cpus_mask));
 }
 
 static inline void task_core_dumping(struct seq_file *m, struct mm_struct *mm)
index 5d52aea..d89526c 100644 (file)
@@ -96,6 +96,7 @@
 #include <linux/posix-timers.h>
 #include <linux/time_namespace.h>
 #include <linux/resctrl.h>
+#include <linux/swait.h>
 #include <trace/events/oom.h>
 #include "internal.h"
 #include "fd.h"
@@ -2038,7 +2039,7 @@ 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 070d2df..a1a964b 100644 (file)
@@ -683,7 +683,7 @@ 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 b1ebf7b..b7e3a6b 100644 (file)
@@ -383,7 +383,8 @@ void pstore_record_init(struct pstore_record *record,
  * end of the buffer.
  */
 static void pstore_dump(struct kmsg_dumper *dumper,
-                       enum kmsg_dump_reason reason)
+                       enum kmsg_dump_reason reason,
+                       struct kmsg_dumper_iter *iter)
 {
        unsigned long   total = 0;
        const char      *why;
@@ -435,7 +436,7 @@ static void pstore_dump(struct kmsg_dumper *dumper,
                dst_size -= header_size;
 
                /* Write dump contents. */
-               if (!kmsg_dump_get_buffer(dumper, true, dst + header_size,
+               if (!kmsg_dump_get_buffer(iter, true, dst + header_size,
                                          dst_size, &dump_size))
                        break;
 
index d1300c6..267f6df 100644 (file)
@@ -30,7 +30,7 @@ mandatory-y += irq.h
 mandatory-y += irq_regs.h
 mandatory-y += irq_work.h
 mandatory-y += kdebug.h
-mandatory-y += kmap_types.h
+mandatory-y += kmap_size.h
 mandatory-y += kprobes.h
 mandatory-y += linkage.h
 mandatory-y += local.h
index d14214d..7317e82 100644 (file)
@@ -7,9 +7,13 @@
 
 typedef struct {
        unsigned int __softirq_pending;
+#ifdef ARCH_WANTS_NMI_IRQSTAT
+       unsigned int __nmi_count;
+#endif
 } ____cacheline_aligned irq_cpustat_t;
 
-#include <linux/irq_cpustat.h> /* Standard mappings for irq_cpustat_t above */
+DECLARE_PER_CPU_ALIGNED(irq_cpustat_t, irq_stat);
+
 #include <linux/irq.h>
 
 #ifndef ack_bad_irq
diff --git a/include/asm-generic/kmap_size.h b/include/asm-generic/kmap_size.h
new file mode 100644 (file)
index 0000000..9d6c778
--- /dev/null
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_GENERIC_KMAP_SIZE_H
+#define _ASM_GENERIC_KMAP_SIZE_H
+
+/* For debug this provides guard pages between the maps */
+#ifdef CONFIG_DEBUG_HIGHMEM
+# define KM_MAX_IDX    33
+#else
+# define KM_MAX_IDX    16
+#endif
+
+#endif
diff --git a/include/asm-generic/kmap_types.h b/include/asm-generic/kmap_types.h
deleted file mode 100644 (file)
index 9f95b7b..0000000
+++ /dev/null
@@ -1,11 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_GENERIC_KMAP_TYPES_H
-#define _ASM_GENERIC_KMAP_TYPES_H
-
-#ifdef __WITH_KM_FENCE
-# define KM_TYPE_NR 41
-#else
-# define KM_TYPE_NR 20
-#endif
-
-#endif
index b4d43a4..ac255e8 100644 (file)
@@ -79,6 +79,9 @@ static __always_inline bool should_resched(int preempt_offset)
 }
 
 #ifdef CONFIG_PREEMPTION
+#ifdef CONFIG_PREEMPT_RT
+extern void preempt_schedule_lock(void);
+#endif
 extern asmlinkage void preempt_schedule(void);
 #define __preempt_schedule() preempt_schedule()
 extern asmlinkage void preempt_schedule_notrace(void);
index 98fdf5a..b35193a 100644 (file)
@@ -161,7 +161,7 @@ struct request {
         */
        union {
                struct hlist_node hash; /* merge hash */
-               struct list_head ipi_list;
+               struct llist_node ipi_list;
        };
 
        /*
index a19519f..eed86eb 100644 (file)
@@ -4,7 +4,7 @@
 
 #include <linux/preempt.h>
 
-#ifdef CONFIG_TRACE_IRQFLAGS
+#if defined(CONFIG_PREEMPT_RT) || defined(CONFIG_TRACE_IRQFLAGS)
 extern void __local_bh_disable_ip(unsigned long ip, unsigned int cnt);
 #else
 static __always_inline void __local_bh_disable_ip(unsigned long ip, unsigned int cnt)
@@ -32,4 +32,10 @@ static inline void local_bh_enable(void)
        __local_bh_enable_ip(_THIS_IP_, SOFTIRQ_DISABLE_OFFSET);
 }
 
+#ifdef CONFIG_PREEMPT_RT
+extern bool local_bh_blocked(void);
+#else
+static inline bool local_bh_blocked(void) { return false; }
+#endif
+
 #endif /* _LINUX_BH_H */
index bc2a749..0272787 100644 (file)
@@ -16,6 +16,7 @@
 
 #include <linux/atomic.h>
 #include <linux/types.h>
+#include <linux/printk.h>
 
 struct vc_data;
 struct console_font_op;
@@ -137,10 +138,12 @@ static inline int con_debug_leave(void)
 #define CON_ANYTIME    (16) /* Safe to call when cpu is offline */
 #define CON_BRL                (32) /* Used for a braille device */
 #define CON_EXTENDED   (64) /* Use the extended output format a la /dev/kmsg */
+#define CON_HANDOVER   (128) /* Device was previously a boot console. */
 
 struct console {
        char    name[16];
        void    (*write)(struct console *, const char *, unsigned);
+       void    (*write_atomic)(struct console *co, const char *s, unsigned int count);
        int     (*read)(struct console *, char *, unsigned);
        struct tty_driver *(*device)(struct console *, int *);
        void    (*unblank)(void);
@@ -150,6 +153,11 @@ struct console {
        short   flags;
        short   index;
        int     cflag;
+#ifdef CONFIG_PRINTK
+       char    sync_buf[CONSOLE_LOG_MAX];
+#endif
+       atomic64_t printk_seq;
+       struct task_struct *thread;
        uint    ispeed;
        uint    ospeed;
        void    *data;
@@ -232,4 +240,7 @@ extern void console_init(void);
 void dummycon_register_output_notifier(struct notifier_block *nb);
 void dummycon_unregister_output_notifier(struct notifier_block *nb);
 
+extern void console_atomic_lock(unsigned int *flags);
+extern void console_atomic_unlock(unsigned int flags);
+
 #endif /* _LINUX_CONSOLE_H */
index 8fb893e..5c0a088 100644 (file)
@@ -153,6 +153,7 @@ enum cpuhp_state {
        CPUHP_AP_ONLINE,
        CPUHP_TEARDOWN_CPU,
        CPUHP_AP_ONLINE_IDLE,
+       CPUHP_AP_SCHED_WAIT_EMPTY,
        CPUHP_AP_SMPBOOT_THREADS,
        CPUHP_AP_X86_VDSO_VMA_ONLINE,
        CPUHP_AP_IRQ_AFFINITY_ONLINE,
index f0d895d..383684e 100644 (file)
@@ -199,6 +199,11 @@ static inline int cpumask_any_and_distribute(const struct cpumask *src1p,
        return cpumask_next_and(-1, src1p, src2p);
 }
 
+static inline int cpumask_any_distribute(const struct cpumask *srcp)
+{
+       return cpumask_first(srcp);
+}
+
 #define for_each_cpu(cpu, mask)                        \
        for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
 #define for_each_cpu_not(cpu, mask)            \
@@ -252,6 +257,7 @@ int cpumask_any_but(const struct cpumask *mask, unsigned int cpu);
 unsigned int cpumask_local_spread(unsigned int i, int node);
 int cpumask_any_and_distribute(const struct cpumask *src1p,
                               const struct cpumask *src2p);
+int cpumask_any_distribute(const struct cpumask *srcp);
 
 /**
  * for_each_cpu - iterate over every cpu in a mask
index 6f95c33..c1290db 100644 (file)
@@ -106,7 +106,7 @@ 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 */
@@ -238,7 +238,7 @@ 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_anon(struct super_block *);
 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 edb5c18..3f49e65 100644 (file)
@@ -3,8 +3,7 @@
 #define __LINUX_DEBUG_LOCKING_H
 
 #include <linux/atomic.h>
-#include <linux/bug.h>
-#include <linux/printk.h>
+#include <linux/cache.h>
 
 struct task_struct;
 
index 1d0e2ce..02b3717 100644 (file)
@@ -76,4 +76,10 @@ static inline void fsleep(unsigned long usecs)
                msleep(DIV_ROUND_UP(usecs, 1000));
 }
 
+#ifdef CONFIG_PREEMPT_RT
+extern void cpu_chill(void);
+#else
+# define cpu_chill()   cpu_relax()
+#endif
+
 #endif /* defined(_LINUX_DELAY_H) */
index 7dff077..78765ca 100644 (file)
@@ -69,7 +69,7 @@
 
 #define EXIT_TO_USER_MODE_WORK                                         \
        (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_UPROBE |           \
-        _TIF_NEED_RESCHED | _TIF_PATCH_PENDING |                       \
+        _TIF_NEED_RESCHED_MASK | _TIF_PATCH_PENDING |                  \
         ARCH_EXIT_TO_USER_MODE_WORK)
 
 /**
index dc4fd8a..836b4c0 100644 (file)
@@ -14,6 +14,7 @@
 #include <linux/err.h>
 #include <linux/percpu-defs.h>
 #include <linux/percpu.h>
+#include <linux/sched.h>
 
 /*
  * CAREFUL: Check include/uapi/asm-generic/fcntl.h when defining
@@ -42,11 +43,9 @@ __u64 eventfd_signal(struct eventfd_ctx *ctx, __u64 n);
 int eventfd_ctx_remove_wait_queue(struct eventfd_ctx *ctx, wait_queue_entry_t *wait,
                                  __u64 *cnt);
 
-DECLARE_PER_CPU(int, eventfd_wake_count);
-
-static inline bool eventfd_signal_count(void)
+static inline bool eventfd_signal_allowed(void)
 {
-       return this_cpu_read(eventfd_wake_count);
+       return !current->in_eventfd_signal;
 }
 
 #else /* CONFIG_EVENTFD */
@@ -77,9 +76,9 @@ static inline int eventfd_ctx_remove_wait_queue(struct eventfd_ctx *ctx,
        return -ENOSYS;
 }
 
-static inline bool eventfd_signal_count(void)
+static inline bool eventfd_signal_allowed(void)
 {
-       return false;
+       return true;
 }
 
 #endif
index 68217bc..9f2be18 100644 (file)
@@ -699,7 +699,7 @@ 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 754f67a..76878b3 100644 (file)
@@ -6,6 +6,7 @@
 #include <linux/preempt.h>
 #include <linux/lockdep.h>
 #include <linux/ftrace_irq.h>
+#include <linux/sched.h>
 #include <linux/vtime.h>
 #include <asm/hardirq.h>
 
@@ -32,9 +33,9 @@ static __always_inline void rcu_irq_enter_check_tick(void)
  */
 #define __irq_enter()                                  \
        do {                                            \
-               account_irq_enter_time(current);        \
                preempt_count_add(HARDIRQ_OFFSET);      \
                lockdep_hardirq_enter();                \
+               account_hardirq_enter(current);         \
        } while (0)
 
 /*
@@ -62,8 +63,8 @@ void irq_enter_rcu(void);
  */
 #define __irq_exit()                                   \
        do {                                            \
+               account_hardirq_exit(current);          \
                lockdep_hardirq_exit();                 \
-               account_irq_exit_time(current);         \
                preempt_count_sub(HARDIRQ_OFFSET);      \
        } while (0)
 
@@ -115,7 +116,6 @@ extern void rcu_nmi_exit(void);
        do {                                                    \
                lockdep_off();                                  \
                arch_nmi_enter();                               \
-               printk_nmi_enter();                             \
                BUG_ON(in_nmi() == NMI_MASK);                   \
                __preempt_count_add(NMI_OFFSET + HARDIRQ_OFFSET);       \
        } while (0)
@@ -134,7 +134,6 @@ extern void rcu_nmi_exit(void);
        do {                                                    \
                BUG_ON(!in_nmi());                              \
                __preempt_count_sub(NMI_OFFSET + HARDIRQ_OFFSET);       \
-               printk_nmi_exit();                              \
                arch_nmi_exit();                                \
                lockdep_on();                                   \
        } while (0)
diff --git a/include/linux/highmem-internal.h b/include/linux/highmem-internal.h
new file mode 100644 (file)
index 0000000..f9bc6ac
--- /dev/null
@@ -0,0 +1,222 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_HIGHMEM_INTERNAL_H
+#define _LINUX_HIGHMEM_INTERNAL_H
+
+/*
+ * Outside of CONFIG_HIGHMEM to support X86 32bit iomap_atomic() cruft.
+ */
+#ifdef CONFIG_KMAP_LOCAL
+void *__kmap_local_pfn_prot(unsigned long pfn, pgprot_t prot);
+void *__kmap_local_page_prot(struct page *page, pgprot_t prot);
+void kunmap_local_indexed(void *vaddr);
+void kmap_local_fork(struct task_struct *tsk);
+void __kmap_local_sched_out(void);
+void __kmap_local_sched_in(void);
+static inline void kmap_assert_nomap(void)
+{
+       DEBUG_LOCKS_WARN_ON(current->kmap_ctrl.idx);
+}
+#else
+static inline void kmap_local_fork(struct task_struct *tsk) { }
+static inline void kmap_assert_nomap(void) { }
+#endif
+
+#ifdef CONFIG_HIGHMEM
+#include <asm/highmem.h>
+
+#ifndef ARCH_HAS_KMAP_FLUSH_TLB
+static inline void kmap_flush_tlb(unsigned long addr) { }
+#endif
+
+#ifndef kmap_prot
+#define kmap_prot PAGE_KERNEL
+#endif
+
+void *kmap_high(struct page *page);
+void kunmap_high(struct page *page);
+void __kmap_flush_unused(void);
+struct page *__kmap_to_page(void *addr);
+
+static inline void *kmap(struct page *page)
+{
+       void *addr;
+
+       might_sleep();
+       if (!PageHighMem(page))
+               addr = page_address(page);
+       else
+               addr = kmap_high(page);
+       kmap_flush_tlb((unsigned long)addr);
+       return addr;
+}
+
+static inline void kunmap(struct page *page)
+{
+       might_sleep();
+       if (!PageHighMem(page))
+               return;
+       kunmap_high(page);
+}
+
+static inline struct page *kmap_to_page(void *addr)
+{
+       return __kmap_to_page(addr);
+}
+
+static inline void kmap_flush_unused(void)
+{
+       __kmap_flush_unused();
+}
+
+static inline void *kmap_local_page(struct page *page)
+{
+       return __kmap_local_page_prot(page, kmap_prot);
+}
+
+static inline void *kmap_local_page_prot(struct page *page, pgprot_t prot)
+{
+       return __kmap_local_page_prot(page, prot);
+}
+
+static inline void *kmap_local_pfn(unsigned long pfn)
+{
+       return __kmap_local_pfn_prot(pfn, kmap_prot);
+}
+
+static inline void __kunmap_local(void *vaddr)
+{
+       kunmap_local_indexed(vaddr);
+}
+
+static inline void *kmap_atomic(struct page *page)
+{
+       if (IS_ENABLED(CONFIG_PREEMPT_RT))
+               migrate_disable();
+       else
+               preempt_disable();
+       pagefault_disable();
+       return __kmap_local_page_prot(page, kmap_prot);
+}
+
+static inline void __kunmap_atomic(void *addr)
+{
+       kunmap_local_indexed(addr);
+       pagefault_enable();
+       if (IS_ENABLED(CONFIG_PREEMPT_RT))
+               migrate_enable();
+       else
+               preempt_enable();
+}
+
+unsigned int __nr_free_highpages(void);
+extern atomic_long_t _totalhigh_pages;
+
+static inline unsigned int nr_free_highpages(void)
+{
+       return __nr_free_highpages();
+}
+
+static inline unsigned long totalhigh_pages(void)
+{
+       return (unsigned long)atomic_long_read(&_totalhigh_pages);
+}
+
+static inline void totalhigh_pages_inc(void)
+{
+       atomic_long_inc(&_totalhigh_pages);
+}
+
+static inline void totalhigh_pages_add(long count)
+{
+       atomic_long_add(count, &_totalhigh_pages);
+}
+
+#else /* CONFIG_HIGHMEM */
+
+static inline struct page *kmap_to_page(void *addr)
+{
+       return virt_to_page(addr);
+}
+
+static inline void *kmap(struct page *page)
+{
+       might_sleep();
+       return page_address(page);
+}
+
+static inline void kunmap_high(struct page *page) { }
+static inline void kmap_flush_unused(void) { }
+
+static inline void kunmap(struct page *page)
+{
+#ifdef ARCH_HAS_FLUSH_ON_KUNMAP
+       kunmap_flush_on_unmap(page_address(page));
+#endif
+}
+
+static inline void *kmap_local_page(struct page *page)
+{
+       return page_address(page);
+}
+
+static inline void *kmap_local_page_prot(struct page *page, pgprot_t prot)
+{
+       return kmap_local_page(page);
+}
+
+static inline void *kmap_local_pfn(unsigned long pfn)
+{
+       return kmap_local_page(pfn_to_page(pfn));
+}
+
+static inline void __kunmap_local(void *addr)
+{
+#ifdef ARCH_HAS_FLUSH_ON_KUNMAP
+       kunmap_flush_on_unmap(addr);
+#endif
+}
+
+static inline void *kmap_atomic(struct page *page)
+{
+       if (IS_ENABLED(CONFIG_PREEMPT_RT))
+               migrate_disable();
+       else
+               preempt_disable();
+       pagefault_disable();
+       return page_address(page);
+}
+
+static inline void __kunmap_atomic(void *addr)
+{
+#ifdef ARCH_HAS_FLUSH_ON_KUNMAP
+       kunmap_flush_on_unmap(addr);
+#endif
+       pagefault_enable();
+       if (IS_ENABLED(CONFIG_PREEMPT_RT))
+               migrate_enable();
+       else
+               preempt_enable();
+}
+
+static inline unsigned int nr_free_highpages(void) { return 0; }
+static inline unsigned long totalhigh_pages(void) { return 0UL; }
+
+#endif /* CONFIG_HIGHMEM */
+
+/*
+ * Prevent people trying to call kunmap_atomic() as if it were kunmap()
+ * kunmap_atomic() should get the return value of kmap_atomic, not the page.
+ */
+#define kunmap_atomic(__addr)                                  \
+do {                                                           \
+       BUILD_BUG_ON(__same_type((__addr), struct page *));     \
+       __kunmap_atomic(__addr);                                \
+} while (0)
+
+#define kunmap_local(__addr)                                   \
+do {                                                           \
+       BUILD_BUG_ON(__same_type((__addr), struct page *));     \
+       __kunmap_local(__addr);                                 \
+} while (0)
+
+#endif
index 14e6202..f597830 100644 (file)
 
 #include <asm/cacheflush.h>
 
-#ifndef ARCH_HAS_FLUSH_ANON_PAGE
-static inline void flush_anon_page(struct vm_area_struct *vma, struct page *page, unsigned long vmaddr)
-{
-}
-#endif
+#include "highmem-internal.h"
 
-#ifndef ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE
-static inline void flush_kernel_dcache_page(struct page *page)
-{
-}
-static inline void flush_kernel_vmap_range(void *vaddr, int size)
-{
-}
-static inline void invalidate_kernel_vmap_range(void *vaddr, int size)
-{
-}
-#endif
-
-#include <asm/kmap_types.h>
-
-#ifdef CONFIG_HIGHMEM
-extern void *kmap_atomic_high_prot(struct page *page, pgprot_t prot);
-extern void kunmap_atomic_high(void *kvaddr);
-#include <asm/highmem.h>
-
-#ifndef ARCH_HAS_KMAP_FLUSH_TLB
-static inline void kmap_flush_tlb(unsigned long addr) { }
-#endif
-
-#ifndef kmap_prot
-#define kmap_prot PAGE_KERNEL
-#endif
-
-void *kmap_high(struct page *page);
-static inline void *kmap(struct page *page)
-{
-       void *addr;
-
-       might_sleep();
-       if (!PageHighMem(page))
-               addr = page_address(page);
-       else
-               addr = kmap_high(page);
-       kmap_flush_tlb((unsigned long)addr);
-       return addr;
-}
-
-void kunmap_high(struct page *page);
-
-static inline void kunmap(struct page *page)
-{
-       might_sleep();
-       if (!PageHighMem(page))
-               return;
-       kunmap_high(page);
-}
-
-/*
- * kmap_atomic/kunmap_atomic is significantly faster than kmap/kunmap because
- * no global lock is needed and because the kmap code must perform a global TLB
- * invalidation when the kmap pool wraps.
+/**
+ * kmap - Map a page for long term usage
+ * @page:      Pointer to the page to be mapped
+ *
+ * Returns: The virtual address of the mapping
+ *
+ * Can only be invoked from preemptible task context because on 32bit
+ * systems with CONFIG_HIGHMEM enabled this function might sleep.
  *
- * However when holding an atomic kmap it is not legal to sleep, so atomic
- * kmaps are appropriate for short, tight code paths only.
+ * For systems with CONFIG_HIGHMEM=n and for pages in the low memory area
+ * this returns the virtual address of the direct kernel mapping.
  *
- * The use of kmap_atomic/kunmap_atomic is discouraged - kmap/kunmap
- * gives a more generic (and caching) interface. But kmap_atomic can
- * be used in IRQ contexts, so in some (very limited) cases we need
- * it.
+ * The returned virtual address is globally visible and valid up to the
+ * point where it is unmapped via kunmap(). The pointer can be handed to
+ * other contexts.
+ *
+ * For highmem pages on 32bit systems this can be slow as the mapping space
+ * is limited and protected by a global lock. In case that there is no
+ * mapping slot available the function blocks until a slot is released via
+ * kunmap().
  */
-static inline void *kmap_atomic_prot(struct page *page, pgprot_t prot)
-{
-       preempt_disable();
-       pagefault_disable();
-       if (!PageHighMem(page))
-               return page_address(page);
-       return kmap_atomic_high_prot(page, prot);
-}
-#define kmap_atomic(page)      kmap_atomic_prot(page, kmap_prot)
-
-/* declarations for linux/mm/highmem.c */
-unsigned int nr_free_highpages(void);
-extern atomic_long_t _totalhigh_pages;
-static inline unsigned long totalhigh_pages(void)
-{
-       return (unsigned long)atomic_long_read(&_totalhigh_pages);
-}
-
-static inline void totalhigh_pages_inc(void)
-{
-       atomic_long_inc(&_totalhigh_pages);
-}
-
-static inline void totalhigh_pages_dec(void)
-{
-       atomic_long_dec(&_totalhigh_pages);
-}
-
-static inline void totalhigh_pages_add(long count)
-{
-       atomic_long_add(count, &_totalhigh_pages);
-}
-
-static inline void totalhigh_pages_set(long val)
-{
-       atomic_long_set(&_totalhigh_pages, val);
-}
-
-void kmap_flush_unused(void);
+static inline void *kmap(struct page *page);
 
-struct page *kmap_to_page(void *addr);
-
-#else /* CONFIG_HIGHMEM */
+/**
+ * kunmap - Unmap the virtual address mapped by kmap()
+ * @addr:      Virtual address to be unmapped
+ *
+ * Counterpart to kmap(). A NOOP for CONFIG_HIGHMEM=n and for mappings of
+ * pages in the low memory area.
+ */
+static inline void kunmap(struct page *page);
 
-static inline unsigned int nr_free_highpages(void) { return 0; }
+/**
+ * kmap_to_page - Get the page for a kmap'ed address
+ * @addr:      The address to look up
+ *
+ * Returns: The page which is mapped to @addr.
+ */
+static inline struct page *kmap_to_page(void *addr);
 
-static inline struct page *kmap_to_page(void *addr)
-{
-       return virt_to_page(addr);
-}
+/**
+ * kmap_flush_unused - Flush all unused kmap mappings in order to
+ *                    remove stray mappings
+ */
+static inline void kmap_flush_unused(void);
 
-static inline unsigned long totalhigh_pages(void) { return 0UL; }
+/**
+ * kmap_local_page - Map a page for temporary usage
+ * @page:      Pointer to the page to be mapped
+ *
+ * Returns: The virtual address of the mapping
+ *
+ * Can be invoked from any context.
+ *
+ * Requires careful handling when nesting multiple mappings because the map
+ * management is stack based. The unmap has to be in the reverse order of
+ * the map operation:
+ *
+ * addr1 = kmap_local_page(page1);
+ * addr2 = kmap_local_page(page2);
+ * ...
+ * kunmap_local(addr2);
+ * kunmap_local(addr1);
+ *
+ * Unmapping addr1 before addr2 is invalid and causes malfunction.
+ *
+ * Contrary to kmap() mappings the mapping is only valid in the context of
+ * the caller and cannot be handed to other contexts.
+ *
+ * On CONFIG_HIGHMEM=n kernels and for low memory pages this returns the
+ * virtual address of the direct mapping. Only real highmem pages are
+ * temporarily mapped.
+ *
+ * While it is significantly faster than kmap() for the higmem case it
+ * comes with restrictions about the pointer validity. Only use when really
+ * necessary.
+ *
+ * On HIGHMEM enabled systems mapping a highmem page has the side effect of
+ * disabling migration in order to keep the virtual address stable across
+ * preemption. No caller of kmap_local_page() can rely on this side effect.
+ */
+static inline void *kmap_local_page(struct page *page);
 
-static inline void *kmap(struct page *page)
-{
-       might_sleep();
-       return page_address(page);
-}
+/**
+ * kmap_atomic - Atomically map a page for temporary usage - Deprecated!
+ * @page:      Pointer to the page to be mapped
+ *
+ * Returns: The virtual address of the mapping
+ *
+ * Effectively a wrapper around kmap_local_page() which disables pagefaults
+ * and preemption.
+ *
+ * Do not use in new code. Use kmap_local_page() instead.
+ */
+static inline void *kmap_atomic(struct page *page);
 
-static inline void kunmap_high(struct page *page)
-{
-}
+/**
+ * kunmap_atomic - Unmap the virtual address mapped by kmap_atomic()
+ * @addr:      Virtual address to be unmapped
+ *
+ * Counterpart to kmap_atomic().
+ *
+ * Effectively a wrapper around kunmap_local() which additionally undoes
+ * the side effects of kmap_atomic(), i.e. reenabling pagefaults and
+ * preemption.
+ */
 
-static inline void kunmap(struct page *page)
-{
-#ifdef ARCH_HAS_FLUSH_ON_KUNMAP
-       kunmap_flush_on_unmap(page_address(page));
-#endif
-}
+/* Highmem related interfaces for management code */
+static inline unsigned int nr_free_highpages(void);
+static inline unsigned long totalhigh_pages(void);
 
-static inline void *kmap_atomic(struct page *page)
+#ifndef ARCH_HAS_FLUSH_ANON_PAGE
+static inline void flush_anon_page(struct vm_area_struct *vma, struct page *page, unsigned long vmaddr)
 {
-       preempt_disable();
-       pagefault_disable();
-       return page_address(page);
 }
-#define kmap_atomic_prot(page, prot)   kmap_atomic(page)
-
-static inline void kunmap_atomic_high(void *addr)
-{
-       /*
-        * Mostly nothing to do in the CONFIG_HIGHMEM=n case as kunmap_atomic()
-        * handles re-enabling faults + preemption
-        */
-#ifdef ARCH_HAS_FLUSH_ON_KUNMAP
-       kunmap_flush_on_unmap(addr);
 #endif
-}
-
-#define kmap_atomic_pfn(pfn)   kmap_atomic(pfn_to_page(pfn))
-
-#define kmap_flush_unused()    do {} while(0)
-
-#endif /* CONFIG_HIGHMEM */
-
-#if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32)
-
-DECLARE_PER_CPU(int, __kmap_atomic_idx);
 
-static inline int kmap_atomic_idx_push(void)
+#ifndef ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE
+static inline void flush_kernel_dcache_page(struct page *page)
 {
-       int idx = __this_cpu_inc_return(__kmap_atomic_idx) - 1;
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-       WARN_ON_ONCE(in_irq() && !irqs_disabled());
-       BUG_ON(idx >= KM_TYPE_NR);
-#endif
-       return idx;
 }
-
-static inline int kmap_atomic_idx(void)
+static inline void flush_kernel_vmap_range(void *vaddr, int size)
 {
-       return __this_cpu_read(__kmap_atomic_idx) - 1;
 }
-
-static inline void kmap_atomic_idx_pop(void)
+static inline void invalidate_kernel_vmap_range(void *vaddr, int size)
 {
-#ifdef CONFIG_DEBUG_HIGHMEM
-       int idx = __this_cpu_dec_return(__kmap_atomic_idx);
-
-       BUG_ON(idx < 0);
-#else
-       __this_cpu_dec(__kmap_atomic_idx);
-#endif
 }
-
 #endif
 
-/*
- * Prevent people trying to call kunmap_atomic() as if it were kunmap()
- * kunmap_atomic() should get the return value of kmap_atomic, not the page.
- */
-#define kunmap_atomic(addr)                                     \
-do {                                                            \
-       BUILD_BUG_ON(__same_type((addr), struct page *));       \
-       kunmap_atomic_high(addr);                                  \
-       pagefault_enable();                                     \
-       preempt_enable();                                       \
-} while (0)
-
-
 /* when CONFIG_HIGHMEM is not set these will be plain clear/copy_page */
 #ifndef clear_user_highpage
 static inline void clear_user_highpage(struct page *page, unsigned long vaddr)
index ee8299e..7545a2f 100644 (file)
@@ -560,7 +560,7 @@ struct softirq_action
 asmlinkage void do_softirq(void);
 asmlinkage void __do_softirq(void);
 
-#ifdef __ARCH_HAS_DO_SOFTIRQ
+#if defined(__ARCH_HAS_DO_SOFTIRQ) && !defined(CONFIG_PREEMPT_RT)
 void do_softirq_own_stack(void);
 #else
 static inline void do_softirq_own_stack(void)
@@ -654,26 +654,21 @@ enum
        TASKLET_STATE_RUN       /* Tasklet is running (SMP only) */
 };
 
-#ifdef CONFIG_SMP
+#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT)
 static inline int tasklet_trylock(struct tasklet_struct *t)
 {
        return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
 }
 
-static inline void tasklet_unlock(struct tasklet_struct *t)
-{
-       smp_mb__before_atomic();
-       clear_bit(TASKLET_STATE_RUN, &(t)->state);
-}
+void tasklet_unlock(struct tasklet_struct *t);
+void tasklet_unlock_wait(struct tasklet_struct *t);
+void tasklet_unlock_spin_wait(struct tasklet_struct *t);
 
-static inline void tasklet_unlock_wait(struct tasklet_struct *t)
-{
-       while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); }
-}
 #else
-#define tasklet_trylock(t) 1
-#define tasklet_unlock_wait(t) do { } while (0)
-#define tasklet_unlock(t) do { } while (0)
+static inline int tasklet_trylock(struct tasklet_struct *t) { return 1; }
+static inline void tasklet_unlock(struct tasklet_struct *t) { }
+static inline void tasklet_unlock_wait(struct tasklet_struct *t) { }
+static inline void tasklet_unlock_spin_wait(struct tasklet_struct *t) { }
 #endif
 
 extern void __tasklet_schedule(struct tasklet_struct *t);
@@ -698,6 +693,17 @@ static inline void tasklet_disable_nosync(struct tasklet_struct *t)
        smp_mb__after_atomic();
 }
 
+/*
+ * Do not use in new code. Disabling tasklets from atomic contexts is
+ * error prone and should be avoided.
+ */
+static inline void tasklet_disable_in_atomic(struct tasklet_struct *t)
+{
+       tasklet_disable_nosync(t);
+       tasklet_unlock_spin_wait(t);
+       smp_mb();
+}
+
 static inline void tasklet_disable(struct tasklet_struct *t)
 {
        tasklet_disable_nosync(t);
index c75e4d3..4bb8223 100644 (file)
@@ -60,22 +60,20 @@ io_mapping_fini(struct io_mapping *mapping)
        iomap_free(mapping->base, mapping->size);
 }
 
-/* Atomic map/unmap */
+/* Temporary mappings which are only valid in the current context */
 static inline void __iomem *
-io_mapping_map_atomic_wc(struct io_mapping *mapping,
-                        unsigned long offset)
+io_mapping_map_local_wc(struct io_mapping *mapping, unsigned long offset)
 {
        resource_size_t phys_addr;
 
        BUG_ON(offset >= mapping->size);
        phys_addr = mapping->base + offset;
-       return iomap_atomic_prot_pfn(PHYS_PFN(phys_addr), mapping->prot);
+       return __iomap_local_pfn_prot(PHYS_PFN(phys_addr), mapping->prot);
 }
 
-static inline void
-io_mapping_unmap_atomic(void __iomem *vaddr)
+static inline void io_mapping_unmap_local(void __iomem *vaddr)
 {
-       iounmap_atomic(vaddr);
+       kunmap_local_indexed((void __force *)vaddr);
 }
 
 static inline void __iomem *
@@ -97,7 +95,7 @@ io_mapping_unmap(void __iomem *vaddr)
        iounmap(vaddr);
 }
 
-#else
+#else  /* HAVE_ATOMIC_IOMAP */
 
 #include <linux/uaccess.h>
 
@@ -144,25 +142,19 @@ io_mapping_unmap(void __iomem *vaddr)
 {
 }
 
-/* Atomic map/unmap */
+/* Temporary mappings which are only valid in the current context */
 static inline void __iomem *
-io_mapping_map_atomic_wc(struct io_mapping *mapping,
-                        unsigned long offset)
+io_mapping_map_local_wc(struct io_mapping *mapping, unsigned long offset)
 {
-       preempt_disable();
-       pagefault_disable();
        return io_mapping_map_wc(mapping, offset, PAGE_SIZE);
 }
 
-static inline void
-io_mapping_unmap_atomic(void __iomem *vaddr)
+static inline void io_mapping_unmap_local(void __iomem *vaddr)
 {
        io_mapping_unmap(vaddr);
-       pagefault_enable();
-       preempt_enable();
 }
 
-#endif /* HAVE_ATOMIC_IOMAP */
+#endif /* !HAVE_ATOMIC_IOMAP */
 
 static inline struct io_mapping *
 io_mapping_create_wc(resource_size_t base,
diff --git a/include/linux/irq_cpustat.h b/include/linux/irq_cpustat.h
deleted file mode 100644 (file)
index 6e8895c..0000000
+++ /dev/null
@@ -1,28 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __irq_cpustat_h
-#define __irq_cpustat_h
-
-/*
- * Contains default mappings for irq_cpustat_t, used by almost every
- * architecture.  Some arch (like s390) have per cpu hardware pages and
- * they define their own mappings for irq_stat.
- *
- * Keith Owens <kaos@ocs.com.au> July 2000.
- */
-
-
-/*
- * Simple wrappers reducing source bloat.  Define all irq_stat fields
- * here, even ones that are arch dependent.  That way we get common
- * definitions instead of differing sets for each arch.
- */
-
-#ifndef __ARCH_IRQ_STAT
-DECLARE_PER_CPU_ALIGNED(irq_cpustat_t, irq_stat);      /* defined in asm/hardirq.h */
-#define __IRQ_STAT(cpu, member)        (per_cpu(irq_stat.member, cpu))
-#endif
-
-/* arch dependent irq_stat fields */
-#define nmi_count(cpu)         __IRQ_STAT((cpu), __nmi_count)  /* i386 */
-
-#endif /* __irq_cpustat_h */
index 3082378..2c00593 100644 (file)
@@ -3,6 +3,7 @@
 #define _LINUX_IRQ_WORK_H
 
 #include <linux/smp_types.h>
+#include <linux/rcuwait.h>
 
 /*
  * An entry can be in one of four states:
@@ -22,6 +23,7 @@ struct irq_work {
                };
        };
        void (*func)(struct irq_work *);
+       struct rcuwait irqwait;
 };
 
 static inline
@@ -29,13 +31,34 @@ void init_irq_work(struct irq_work *work, void (*func)(struct irq_work *))
 {
        atomic_set(&work->flags, 0);
        work->func = func;
+       rcuwait_init(&work->irqwait);
 }
 
 #define DEFINE_IRQ_WORK(name, _f) struct irq_work name = {     \
                .flags = ATOMIC_INIT(0),                        \
-               .func  = (_f)                                   \
+               .func  = (_f),                                  \
+               .irqwait = __RCUWAIT_INITIALIZER(irqwait),      \
 }
 
+#define __IRQ_WORK_INIT(_func, _flags) (struct irq_work){      \
+       .flags = ATOMIC_INIT(_flags),                           \
+       .func = (_func),                                        \
+       .irqwait = __RCUWAIT_INITIALIZER(irqwait),              \
+}
+
+#define IRQ_WORK_INIT(_func) __IRQ_WORK_INIT(_func, 0)
+#define IRQ_WORK_INIT_LAZY(_func) __IRQ_WORK_INIT(_func, IRQ_WORK_LAZY)
+#define IRQ_WORK_INIT_HARD(_func) __IRQ_WORK_INIT(_func, IRQ_WORK_HARD_IRQ)
+
+static inline bool irq_work_is_busy(struct irq_work *work)
+{
+       return atomic_read(&work->flags) & IRQ_WORK_BUSY;
+}
+
+static inline bool irq_work_is_hard(struct irq_work *work)
+{
+       return atomic_read(&work->flags) & IRQ_WORK_HARD_IRQ;
+}
 
 bool irq_work_queue(struct irq_work *work);
 bool irq_work_queue_on(struct irq_work *work, int cpu);
index 5745491..2b9caf3 100644 (file)
@@ -68,6 +68,7 @@ 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 3ed4e87..a437b2e 100644 (file)
@@ -71,14 +71,6 @@ do {                                         \
 do {                                           \
        __this_cpu_dec(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 lockdep_hrtimer_enter(__hrtimer)              \
 ({                                                     \
@@ -140,6 +132,21 @@ do {                                               \
 # define lockdep_irq_work_exit(__work)         do { } while (0)
 #endif
 
+#if defined(CONFIG_TRACE_IRQFLAGS) && !defined(CONFIG_PREEMPT_RT)
+# 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)
+#endif
+
 #if defined(CONFIG_IRQSOFF_TRACER) || \
        defined(CONFIG_PREEMPT_TRACER)
  extern void stop_critical_timings(void);
index 2f05e91..6eb0ab9 100644 (file)
@@ -204,6 +204,7 @@ extern int _cond_resched(void);
 extern void ___might_sleep(const char *file, int line, int preempt_offset);
 extern void __might_sleep(const char *file, int line, int preempt_offset);
 extern void __cant_sleep(const char *file, int line, int preempt_offset);
+extern void __cant_migrate(const char *file, int line);
 
 /**
  * might_sleep - annotation for functions that can sleep
@@ -219,6 +220,10 @@ extern void __cant_sleep(const char *file, int line, int preempt_offset);
  */
 # 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); } while (0)
+
 /**
  * cant_sleep - annotation for functions that cannot sleep
  *
@@ -227,6 +232,18 @@ extern void __cant_sleep(const char *file, int line, int preempt_offset);
 # define cant_sleep() \
        do { __cant_sleep(__FILE__, __LINE__, 0); } while (0)
 # define sched_annotate_sleep()        (current->task_state_change = 0)
+
+/**
+ * cant_migrate - annotation for functions that cannot migrate
+ *
+ * Will print a stack trace if executed in code which is migratable
+ */
+# define cant_migrate()                                                        \
+       do {                                                            \
+               if (IS_ENABLED(CONFIG_SMP))                             \
+                       __cant_migrate(__FILE__, __LINE__);             \
+       } while (0)
+
 /**
  * non_block_start - annotate the start of section where sleeping is prohibited
  *
@@ -250,7 +267,9 @@ extern void __cant_sleep(const char *file, int line, int preempt_offset);
   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 cant_sleep() do { } while (0)
+# define cant_migrate()                do { } while (0)
 # define sched_annotate_sleep() do { } while (0)
 # define non_block_start() do { } while (0)
 # define non_block_end() do { } while (0)
@@ -258,13 +277,6 @@ extern void __cant_sleep(const char *file, int line, int preempt_offset);
 
 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
 
-#ifndef CONFIG_PREEMPT_RT
-# define cant_migrate()                cant_sleep()
-#else
-  /* Placeholder for now */
-# define cant_migrate()                do { } while (0)
-#endif
-
 /**
  * abs - return absolute value of an argument
  * @x: the value.  If it is unsigned type, it is converted to signed type first.
index 3378bcb..8667393 100644 (file)
@@ -30,6 +30,18 @@ enum kmsg_dump_reason {
 };
 
 /**
+ * struct kmsg_dumper_iter - iterator for kernel crash message dumper
+ * @active:    Flag that specifies if this is currently dumping
+ * @cur_seq:   Points to the oldest message to dump (private)
+ * @next_seq:  Points after the newest message to dump (private)
+ */
+struct kmsg_dumper_iter {
+       bool    active;
+       u64     cur_seq;
+       u64     next_seq;
+};
+
+/**
  * struct kmsg_dumper - kernel crash message dumper structure
  * @list:      Entry in the dumper list (private)
  * @dump:      Call into dumping code which will retrieve the data with
@@ -39,33 +51,22 @@ enum kmsg_dump_reason {
  */
 struct kmsg_dumper {
        struct list_head list;
-       void (*dump)(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason);
+       void (*dump)(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason,
+                    struct kmsg_dumper_iter *iter);
        enum kmsg_dump_reason max_reason;
-       bool active;
        bool registered;
-
-       /* private state of the kmsg iterator */
-       u32 cur_idx;
-       u32 next_idx;
-       u64 cur_seq;
-       u64 next_seq;
 };
 
 #ifdef CONFIG_PRINTK
 void kmsg_dump(enum kmsg_dump_reason reason);
 
-bool kmsg_dump_get_line_nolock(struct kmsg_dumper *dumper, bool syslog,
-                              char *line, size_t size, size_t *len);
-
-bool kmsg_dump_get_line(struct kmsg_dumper *dumper, bool syslog,
+bool kmsg_dump_get_line(struct kmsg_dumper_iter *iter, bool syslog,
                        char *line, size_t size, size_t *len);
 
-bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog,
-                         char *buf, size_t size, size_t *len);
-
-void kmsg_dump_rewind_nolock(struct kmsg_dumper *dumper);
+bool kmsg_dump_get_buffer(struct kmsg_dumper_iter *iter, bool syslog,
+                         char *buf, size_t size, size_t *len_out);
 
-void kmsg_dump_rewind(struct kmsg_dumper *dumper);
+void kmsg_dump_rewind(struct kmsg_dumper_iter *iter);
 
 int kmsg_dump_register(struct kmsg_dumper *dumper);
 
@@ -77,30 +78,19 @@ static inline void kmsg_dump(enum kmsg_dump_reason reason)
 {
 }
 
-static inline bool kmsg_dump_get_line_nolock(struct kmsg_dumper *dumper,
-                                            bool syslog, const char *line,
-                                            size_t size, size_t *len)
-{
-       return false;
-}
-
-static inline bool kmsg_dump_get_line(struct kmsg_dumper *dumper, bool syslog,
+static inline bool kmsg_dump_get_line(struct kmsg_dumper_iter *iter, bool syslog,
                                const char *line, size_t size, size_t *len)
 {
        return false;
 }
 
-static inline bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog,
+static inline bool kmsg_dump_get_buffer(struct kmsg_dumper_iter *iter, bool syslog,
                                        char *buf, size_t size, size_t *len)
 {
        return false;
 }
 
-static inline void kmsg_dump_rewind_nolock(struct kmsg_dumper *dumper)
-{
-}
-
-static inline void kmsg_dump_rewind(struct kmsg_dumper *dumper)
+static inline void kmsg_dump_rewind(struct kmsg_dumper_iter *iter)
 {
 }
 
index 3f02b81..1b8ae03 100644 (file)
@@ -7,13 +7,39 @@
 #include <linux/lockdep.h>
 
 typedef struct {
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
+#ifdef CONFIG_PREEMPT_RT
+       spinlock_t              lock;
+       struct task_struct      *owner;
+       int                     nestcnt;
+
+#elif defined(CONFIG_DEBUG_LOCK_ALLOC)
        struct lockdep_map      dep_map;
        struct task_struct      *owner;
 #endif
 } local_lock_t;
 
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
+#ifdef CONFIG_PREEMPT_RT
+
+#define INIT_LOCAL_LOCK(lockname)      {       \
+       __SPIN_LOCK_UNLOCKED((lockname).lock),  \
+       .owner          = NULL,                 \
+       .nestcnt        = 0,                    \
+       }
+
+static inline void ___local_lock_init(local_lock_t *l)
+{
+       l->owner = NULL;
+       l->nestcnt = 0;
+}
+
+#define __local_lock_init(l)                                   \
+do {                                                           \
+       spin_lock_init(&(l)->lock);                             \
+       ___local_lock_init(l);                                  \
+} while (0)
+
+#elif defined(CONFIG_DEBUG_LOCK_ALLOC)
+
 # define LOCAL_LOCK_DEBUG_INIT(lockname)               \
        .dep_map = {                                    \
                .name = #lockname,                      \
@@ -21,9 +47,35 @@ typedef struct {
                .lock_type = LD_LOCK_PERCPU,            \
        },                                              \
        .owner = NULL,
+#endif
+
+#ifdef CONFIG_PREEMPT_RT
 
 static inline void local_lock_acquire(local_lock_t *l)
 {
+       if (l->owner != current) {
+               spin_lock(&l->lock);
+               DEBUG_LOCKS_WARN_ON(l->owner);
+               DEBUG_LOCKS_WARN_ON(l->nestcnt);
+               l->owner = current;
+       }
+       l->nestcnt++;
+}
+
+static inline void local_lock_release(local_lock_t *l)
+{
+       DEBUG_LOCKS_WARN_ON(l->nestcnt == 0);
+       DEBUG_LOCKS_WARN_ON(l->owner != current);
+       if (--l->nestcnt)
+               return;
+
+       l->owner = NULL;
+       spin_unlock(&l->lock);
+}
+
+#elif defined(CONFIG_DEBUG_LOCK_ALLOC)
+static inline void local_lock_acquire(local_lock_t *l)
+{
        lock_map_acquire(&l->dep_map);
        DEBUG_LOCKS_WARN_ON(l->owner);
        l->owner = current;
@@ -47,6 +99,47 @@ static inline void local_lock_release(local_lock_t *l) { }
 static inline void local_lock_debug_init(local_lock_t *l) { }
 #endif /* !CONFIG_DEBUG_LOCK_ALLOC */
 
+#ifdef CONFIG_PREEMPT_RT
+
+#define __local_lock(lock)                                     \
+       do {                                                    \
+               migrate_disable();                              \
+               local_lock_acquire(this_cpu_ptr(lock));         \
+       } while (0)
+
+#define __local_unlock(lock)                                   \
+       do {                                                    \
+               local_lock_release(this_cpu_ptr(lock));         \
+               migrate_enable();                               \
+       } while (0)
+
+#define __local_lock_irq(lock)                                 \
+       do {                                                    \
+               migrate_disable();                              \
+               local_lock_acquire(this_cpu_ptr(lock));         \
+       } while (0)
+
+#define __local_lock_irqsave(lock, flags)                      \
+       do {                                                    \
+               migrate_disable();                              \
+               flags = 0;                                      \
+               local_lock_acquire(this_cpu_ptr(lock));         \
+       } while (0)
+
+#define __local_unlock_irq(lock)                               \
+       do {                                                    \
+               local_lock_release(this_cpu_ptr(lock));         \
+               migrate_enable();                               \
+       } while (0)
+
+#define __local_unlock_irqrestore(lock, flags)                 \
+       do {                                                    \
+               local_lock_release(this_cpu_ptr(lock));         \
+               migrate_enable();                               \
+       } while (0)
+
+#else
+
 #define INIT_LOCAL_LOCK(lockname)      { LOCAL_LOCK_DEBUG_INIT(lockname) }
 
 #define __local_lock_init(lock)                                        \
@@ -66,6 +159,12 @@ do {                                                                \
                local_lock_acquire(this_cpu_ptr(lock));         \
        } while (0)
 
+#define __local_unlock(lock)                                   \
+       do {                                                    \
+               local_lock_release(this_cpu_ptr(lock));         \
+               preempt_enable();                               \
+       } while (0)
+
 #define __local_lock_irq(lock)                                 \
        do {                                                    \
                local_irq_disable();                            \
@@ -78,12 +177,6 @@ do {                                                                \
                local_lock_acquire(this_cpu_ptr(lock));         \
        } while (0)
 
-#define __local_unlock(lock)                                   \
-       do {                                                    \
-               local_lock_release(this_cpu_ptr(lock));         \
-               preempt_enable();                               \
-       } while (0)
-
 #define __local_unlock_irq(lock)                               \
        do {                                                    \
                local_lock_release(this_cpu_ptr(lock));         \
@@ -95,3 +188,5 @@ do {                                                         \
                local_lock_release(this_cpu_ptr(lock));         \
                local_irq_restore(flags);                       \
        } while (0)
+
+#endif
index 4eb3891..2a83d96 100644 (file)
@@ -12,6 +12,7 @@
 #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 <linux/seqlock.h>
@@ -570,6 +571,9 @@ struct mm_struct {
                bool tlb_flush_batched;
 #endif
                struct uprobes_state uprobes_state;
+#ifdef CONFIG_PREEMPT_RT
+               struct rcu_head delayed_drop;
+#endif
 #ifdef CONFIG_HUGETLB_PAGE
                atomic_long_t hugetlb_usage;
 #endif
index 4d671fb..90923d3 100644 (file)
 
 struct ww_acquire_ctx;
 
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define __DEP_MAP_MUTEX_INITIALIZER(lockname)                 \
+               , .dep_map = {                                  \
+                       .name = #lockname,                      \
+                       .wait_type_inner = LD_WAIT_SLEEP,       \
+               }
+#else
+# define __DEP_MAP_MUTEX_INITIALIZER(lockname)
+#endif
+
+#ifdef CONFIG_PREEMPT_RT
+# include <linux/mutex_rt.h>
+#else
+
 /*
  * Simple, straightforward mutexes with strict semantics:
  *
@@ -68,14 +82,6 @@ struct mutex {
 struct ww_class;
 struct ww_acquire_ctx;
 
-struct ww_mutex {
-       struct mutex base;
-       struct ww_acquire_ctx *ctx;
-#ifdef CONFIG_DEBUG_MUTEXES
-       struct ww_class *ww_class;
-#endif
-};
-
 /*
  * This is the control structure for tasks blocked on mutex,
  * which resides on the blocked task's kernel stack:
@@ -119,16 +125,6 @@ do {                                                                       \
        __mutex_init((mutex), #mutex, &__key);                          \
 } while (0)
 
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# define __DEP_MAP_MUTEX_INITIALIZER(lockname)                 \
-               , .dep_map = {                                  \
-                       .name = #lockname,                      \
-                       .wait_type_inner = LD_WAIT_SLEEP,       \
-               }
-#else
-# define __DEP_MAP_MUTEX_INITIALIZER(lockname)
-#endif
-
 #define __MUTEX_INITIALIZER(lockname) \
                { .owner = ATOMIC_LONG_INIT(0) \
                , .wait_lock = __SPIN_LOCK_UNLOCKED(lockname.wait_lock) \
@@ -224,4 +220,6 @@ enum mutex_trylock_recursive_enum {
 extern /* __deprecated */ __must_check enum mutex_trylock_recursive_enum
 mutex_trylock_recursive(struct mutex *lock);
 
+#endif /* !PREEMPT_RT */
+
 #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..f0b2e07
--- /dev/null
@@ -0,0 +1,130 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#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 void __lockfunc _mutex_lock_io_nested(struct mutex *lock, int subclass);
+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)
+#define mutex_lock_io(l)               _mutex_lock_io_nested(l, 0);
+
+#define __mutex_owner(l)               ((l)->lock.owner)
+
+#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_io_nested(l, s)    _mutex_lock_io_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)
+# define mutex_lock_io_nested(l, s)    _mutex_lock_io_nested(l, s)
+#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)
+
+/**
+ * These values are chosen such that FAIL and SUCCESS match the
+ * values of the regular mutex_trylock().
+ */
+enum mutex_trylock_recursive_enum {
+       MUTEX_TRYLOCK_FAILED    = 0,
+       MUTEX_TRYLOCK_SUCCESS   = 1,
+       MUTEX_TRYLOCK_RECURSIVE,
+};
+/**
+ * mutex_trylock_recursive - trylock variant that allows recursive locking
+ * @lock: mutex to be locked
+ *
+ * This function should not be used, _ever_. It is purely for hysterical GEM
+ * raisins, and once those are gone this will be removed.
+ *
+ * Returns:
+ *  MUTEX_TRYLOCK_FAILED    - trylock failed,
+ *  MUTEX_TRYLOCK_SUCCESS   - lock acquired,
+ *  MUTEX_TRYLOCK_RECURSIVE - we already owned the lock.
+ */
+int __rt_mutex_owner_current(struct rt_mutex *lock);
+
+static inline /* __deprecated */ __must_check enum mutex_trylock_recursive_enum
+mutex_trylock_recursive(struct mutex *lock)
+{
+       if (unlikely(__rt_mutex_owner_current(&lock->lock)))
+               return MUTEX_TRYLOCK_RECURSIVE;
+
+       return mutex_trylock(lock);
+}
+
+extern int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock);
+
+#endif
index 5491ad5..cd9e5b3 100644 (file)
@@ -1675,7 +1675,7 @@ struct nfs_unlinkdata {
        struct nfs_removeargs args;
        struct nfs_removeres res;
        struct dentry *dentry;
-       wait_queue_head_t wq;
+       struct swait_queue_head wq;
        const struct cred *cred;
        struct nfs_fattr dir_attr;
        long timeout;
index 2fb373a..723bc2d 100644 (file)
@@ -58,7 +58,7 @@ struct notifier_block {
 };
 
 struct atomic_notifier_head {
-       spinlock_t lock;
+       raw_spinlock_t lock;
        struct notifier_block __rcu *head;
 };
 
@@ -78,7 +78,7 @@ struct srcu_notifier_head {
 };
 
 #define ATOMIC_INIT_NOTIFIER_HEAD(name) do {   \
-               spin_lock_init(&(name)->lock);  \
+               raw_spin_lock_init(&(name)->lock);      \
                (name)->head = NULL;            \
        } while (0)
 #define BLOCKING_INIT_NOTIFIER_HEAD(name) do { \
@@ -95,7 +95,7 @@ extern void srcu_init_notifier_head(struct srcu_notifier_head *nh);
                cleanup_srcu_struct(&(name)->srcu);
 
 #define ATOMIC_NOTIFIER_INIT(name) {                           \
-               .lock = __SPIN_LOCK_UNLOCKED(name.lock),        \
+               .lock = __RAW_SPIN_LOCK_UNLOCKED(name.lock),    \
                .head = NULL }
 #define BLOCKING_NOTIFIER_INIT(name) {                         \
                .rwsem = __RWSEM_INITIALIZER((name).rwsem),     \
index a19f612..570894a 100644 (file)
@@ -3,6 +3,7 @@
 #define _LINUX_PID_H
 
 #include <linux/rculist.h>
+#include <linux/atomic.h>
 #include <linux/wait.h>
 #include <linux/refcount.h>
 
index 7d9c1c0..7b5b2ed 100644 (file)
 /* preempt_count() and related functions, depends on PREEMPT_NEED_RESCHED */
 #include <asm/preempt.h>
 
+#define nmi_count()    (preempt_count() & NMI_MASK)
 #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))
+#ifdef CONFIG_PREEMPT_RT
+# define softirq_count()       (current->softirq_disable_cnt & SOFTIRQ_MASK)
+#else
+# define softirq_count()       (preempt_count() & SOFTIRQ_MASK)
+#endif
+#define irq_count()    (nmi_count() | hardirq_count() | softirq_count())
 
 /*
- * Are we doing bottom half or hardware interrupt processing?
+ * Macros to retrieve the current execution context:
  *
- * in_irq()       - We're in (hard) IRQ context
+ * in_nmi()            - We're in NMI context
+ * in_hardirq()                - We're in hard IRQ context
+ * in_serving_softirq()        - We're in softirq context
+ * in_task()           - We're in task context
+ */
+#define in_nmi()               (nmi_count())
+#define in_hardirq()           (hardirq_count())
+#define in_serving_softirq()   (softirq_count() & SOFTIRQ_OFFSET)
+#define in_task()              (!(in_nmi() | in_hardirq() | in_serving_softirq()))
+
+/*
+ * The following macros are deprecated and should not be used in new code:
+ * in_irq()       - Obsolete version of in_hardirq()
  * in_softirq()   - We have BH disabled, or are processing softirqs
  * in_interrupt() - We're in NMI,IRQ,SoftIRQ context or have BH disabled
- * in_serving_softirq() - We're in softirq context
- * in_nmi()       - We're in NMI context
- * in_task()     - We're in task context
- *
- * Note: due to the BH disabled confusion: in_softirq(),in_interrupt() really
- *       should not be used in new code.
  */
 #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 preempt_disable();
 /*
  * The preempt_count offset after spin_lock()
  */
+#if !defined(CONFIG_PREEMPT_RT)
 #define PREEMPT_LOCK_OFFSET    PREEMPT_DISABLE_OFFSET
+#else
+#define PREEMPT_LOCK_OFFSET    0
+#endif
 
 /*
  * The preempt_count offset needed for things like:
@@ -164,6 +174,20 @@ 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() \
@@ -172,13 +196,25 @@ 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()
+#ifndef CONFIG_PREEMPT_RT
+# define preempt_enable_no_resched() sched_preempt_enable_no_resched()
+# define preempt_check_resched_rt() barrier();
+#else
+# define preempt_enable_no_resched() preempt_enable()
+# define preempt_check_resched_rt() preempt_check_resched()
+#endif
 
 #define preemptible()  (preempt_count() == 0 && !irqs_disabled())
 
@@ -203,6 +239,18 @@ do { \
                __preempt_schedule(); \
 } while (0)
 
+/*
+ * open code preempt_check_resched() because it is not exported to modules and
+ * used by local_unlock() or bpf_enable_instrumentation().
+ */
+#define preempt_lazy_enable() \
+do { \
+       dec_preempt_lazy_count(); \
+       barrier(); \
+       if (should_resched(0)) \
+               __preempt_schedule(); \
+} while (0)
+
 #else /* !CONFIG_PREEMPTION */
 #define preempt_enable() \
 do { \
@@ -210,6 +258,12 @@ do { \
        preempt_count_dec(); \
 } while (0)
 
+#define preempt_lazy_enable() \
+do { \
+       dec_preempt_lazy_count(); \
+       barrier(); \
+} while (0)
+
 #define preempt_enable_notrace() \
 do { \
        barrier(); \
@@ -248,8 +302,12 @@ 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
 
+#define preempt_lazy_disable()                 barrier()
+#define preempt_lazy_enable()                  barrier()
+
 #endif /* CONFIG_PREEMPT_COUNT */
 
 #ifdef MODULE
@@ -268,10 +326,22 @@ 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
+# define preempt_disable_rt()          preempt_disable()
+# define preempt_enable_rt()           preempt_enable()
+# define preempt_disable_nort()                barrier()
+# define preempt_enable_nort()         barrier()
+#else
+# define preempt_disable_rt()          barrier()
+# define preempt_enable_rt()           barrier()
+# define preempt_disable_nort()                preempt_disable()
+# define preempt_enable_nort()         preempt_enable()
+#endif
+
 #ifdef CONFIG_PREEMPT_NOTIFIERS
 
 struct preempt_notifier;
@@ -322,34 +392,78 @@ static inline void preempt_notifier_init(struct preempt_notifier *notifier,
 
 #endif
 
-/**
- * migrate_disable - Prevent migration of the current task
+#ifdef CONFIG_SMP
+
+/*
+ * Migrate-Disable and why it is undesired.
  *
- * Maps to preempt_disable() which also disables preemption. Use
- * migrate_disable() to annotate that the intent is to prevent migration,
- * but not necessarily preemption.
+ * When a preempted task becomes elegible to run under the ideal model (IOW it
+ * becomes one of the M highest priority tasks), it might still have to wait
+ * for the preemptee's migrate_disable() section to complete. Thereby suffering
+ * a reduction in bandwidth in the exact duration of the migrate_disable()
+ * section.
  *
- * Can be invoked nested like preempt_disable() and needs the corresponding
- * number of migrate_enable() invocations.
- */
-static __always_inline void migrate_disable(void)
-{
-       preempt_disable();
-}
-
-/**
- * migrate_enable - Allow migration of the current task
+ * Per this argument, the change from preempt_disable() to migrate_disable()
+ * gets us:
+ *
+ * - a higher priority tasks gains reduced wake-up latency; with preempt_disable()
+ *   it would have had to wait for the lower priority task.
+ *
+ * - a lower priority tasks; which under preempt_disable() could've instantly
+ *   migrated away when another CPU becomes available, is now constrained
+ *   by the ability to push the higher priority task away, which might itself be
+ *   in a migrate_disable() section, reducing it's available bandwidth.
+ *
+ * IOW it trades latency / moves the interference term, but it stays in the
+ * system, and as long as it remains unbounded, the system is not fully
+ * deterministic.
  *
- * Counterpart to migrate_disable().
  *
- * As migrate_disable() can be invoked nested, only the outermost invocation
- * reenables migration.
+ * The reason we have it anyway.
+ *
+ * PREEMPT_RT breaks a number of assumptions traditionally held. By forcing a
+ * number of primitives into becoming preemptible, they would also allow
+ * migration. This turns out to break a bunch of per-cpu usage. To this end,
+ * all these primitives employ migirate_disable() to restore this implicit
+ * assumption.
+ *
+ * This is a 'temporary' work-around at best. The correct solution is getting
+ * rid of the above assumptions and reworking the code to employ explicit
+ * per-cpu locking or short preempt-disable regions.
+ *
+ * The end goal must be to get rid of migrate_disable(), alternatively we need
+ * a schedulability theory that does not depend on abritrary migration.
+ *
+ *
+ * Notes on the implementation.
+ *
+ * The implementation is particularly tricky since existing code patterns
+ * dictate neither migrate_disable() nor migrate_enable() is allowed to block.
+ * This means that it cannot use cpus_read_lock() to serialize against hotplug,
+ * nor can it easily migrate itself into a pending affinity mask change on
+ * migrate_enable().
+ *
+ *
+ * Note: even non-work-conserving schedulers like semi-partitioned depends on
+ *       migration, so migrate_disable() is not only a problem for
+ *       work-conserving schedulers.
  *
- * Currently mapped to preempt_enable().
  */
-static __always_inline void migrate_enable(void)
+extern void migrate_disable(void);
+extern void migrate_enable(void);
+
+#else
+
+static inline void migrate_disable(void)
 {
-       preempt_enable();
+       preempt_lazy_disable();
 }
 
+static inline void migrate_enable(void)
+{
+       preempt_lazy_enable();
+}
+
+#endif /* CONFIG_SMP */
+
 #endif /* __LINUX_PREEMPT_H */
index fe7eb23..7e43524 100644 (file)
@@ -46,6 +46,12 @@ static inline const char *printk_skip_headers(const char *buffer)
 
 #define CONSOLE_EXT_LOG_MAX    8192
 
+/*
+ * The maximum size of a record formatted for console printing
+ * (i.e. with the prefix prepended to every line).
+ */
+#define CONSOLE_LOG_MAX                4096
+
 /* printk's without a loglevel use this.. */
 #define MESSAGE_LOGLEVEL_DEFAULT CONFIG_MESSAGE_LOGLEVEL_DEFAULT
 
@@ -149,18 +155,6 @@ static inline __printf(1, 2) __cold
 void early_printk(const char *s, ...) { }
 #endif
 
-#ifdef CONFIG_PRINTK_NMI
-extern void printk_nmi_enter(void);
-extern void printk_nmi_exit(void);
-extern void printk_nmi_direct_enter(void);
-extern void printk_nmi_direct_exit(void);
-#else
-static inline void printk_nmi_enter(void) { }
-static inline void printk_nmi_exit(void) { }
-static inline void printk_nmi_direct_enter(void) { }
-static inline void printk_nmi_direct_exit(void) { }
-#endif /* PRINTK_NMI */
-
 struct dev_printk_info;
 
 #ifdef CONFIG_PRINTK
@@ -207,8 +201,6 @@ __printf(1, 2) void dump_stack_set_arch_desc(const char *fmt, ...);
 void dump_stack_print_info(const char *log_lvl);
 void show_regs_print_info(const char *log_lvl);
 extern asmlinkage void dump_stack(void) __cold;
-extern void printk_safe_flush(void);
-extern void printk_safe_flush_on_panic(void);
 #else
 static inline __printf(1, 0)
 int vprintk(const char *s, va_list args)
@@ -272,14 +264,6 @@ static inline void show_regs_print_info(const char *log_lvl)
 static inline void dump_stack(void)
 {
 }
-
-static inline void printk_safe_flush(void)
-{
-}
-
-static inline void printk_safe_flush_on_panic(void)
-{
-}
 #endif
 
 extern int kptr_restrict;
@@ -497,6 +481,8 @@ extern int kptr_restrict;
        no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 #endif
 
+bool pr_flush(int timeout_ms, bool reset_on_progress);
+
 /*
  * ratelimited messages with local ratelimit_state,
  * no local ratelimit_state used in the !PRINTK case
index f45b8be..0e41d05 100644 (file)
@@ -35,7 +35,7 @@ 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 wait_for_random_bytes(void);
index d7db179..c33b0e1 100644 (file)
 
 #include <linux/kernel.h>
 #include <linux/stddef.h>
+#include <linux/rbtree_type.h>
 #include <linux/rcupdate.h>
 
-struct rb_node {
-       unsigned long  __rb_parent_color;
-       struct rb_node *rb_right;
-       struct rb_node *rb_left;
-} __attribute__((aligned(sizeof(long))));
-    /* The alignment might seem pointless, but allegedly CRIS needs it */
-
-struct rb_root {
-       struct rb_node *rb_node;
-};
-
 #define rb_parent(r)   ((struct rb_node *)((r)->__rb_parent_color & ~3))
 
 #define RB_ROOT        (struct rb_root) { NULL, }
@@ -112,21 +102,6 @@ static inline void rb_link_node_rcu(struct rb_node *node, struct rb_node *parent
                        typeof(*pos), field); 1; }); \
             pos = n)
 
-/*
- * Leftmost-cached rbtrees.
- *
- * We do not cache the rightmost node based on footprint
- * size vs number of potential users that could benefit
- * from O(1) rb_last(). Just not worth it, users that want
- * this feature can always implement the logic explicitly.
- * Furthermore, users that want to cache both pointers may
- * find it a bit asymmetric, but that's ok.
- */
-struct rb_root_cached {
-       struct rb_root rb_root;
-       struct rb_node *rb_leftmost;
-};
-
 #define RB_ROOT_CACHED (struct rb_root_cached) { {NULL, }, NULL }
 
 /* Same as rb_first(), but O(1) */
diff --git a/include/linux/rbtree_type.h b/include/linux/rbtree_type.h
new file mode 100644 (file)
index 0000000..77a89dd
--- /dev/null
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _LINUX_RBTREE_TYPE_H
+#define _LINUX_RBTREE_TYPE_H
+
+struct rb_node {
+       unsigned long  __rb_parent_color;
+       struct rb_node *rb_right;
+       struct rb_node *rb_left;
+} __attribute__((aligned(sizeof(long))));
+/* The alignment might seem pointless, but allegedly CRIS needs it */
+
+struct rb_root {
+       struct rb_node *rb_node;
+};
+
+/*
+ * Leftmost-cached rbtrees.
+ *
+ * We do not cache the rightmost node based on footprint
+ * size vs number of potential users that could benefit
+ * from O(1) rb_last(). Just not worth it, users that want
+ * this feature can always implement the logic explicitly.
+ * Furthermore, users that want to cache both pointers may
+ * find it a bit asymmetric, but that's ok.
+ */
+struct rb_root_cached {
+       struct rb_root rb_root;
+       struct rb_node *rb_leftmost;
+};
+
+#endif
index 095b3b3..1effcae 100644 (file)
@@ -54,6 +54,11 @@ void __rcu_read_unlock(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
+#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 */
 
@@ -79,6 +84,8 @@ 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 */
@@ -329,7 +336,8 @@ static inline void rcu_preempt_sleep_check(void) { }
 #define rcu_sleep_check()                                              \
        do {                                                            \
                rcu_preempt_sleep_check();                              \
-               RCU_LOCKDEP_WARN(lock_is_held(&rcu_bh_lock_map),        \
+               if (!IS_ENABLED(CONFIG_PREEMPT_RT))                     \
+                   RCU_LOCKDEP_WARN(lock_is_held(&rcu_bh_lock_map),    \
                                 "Illegal context switch in RCU-bh read-side critical section"); \
                RCU_LOCKDEP_WARN(lock_is_held(&rcu_sched_lock_map),     \
                                 "Illegal context switch in RCU-sched read-side critical section"); \
index 6fd615a..b02009f 100644 (file)
 #define __LINUX_RT_MUTEX_H
 
 #include <linux/linkage.h>
-#include <linux/rbtree.h>
-#include <linux/spinlock_types.h>
+#include <linux/rbtree_type.h>
+#include <linux/spinlock_types_raw.h>
 
 extern int max_lock_depth; /* for sysctl */
 
+#ifdef CONFIG_DEBUG_MUTEXES
+#include <linux/debug_locks.h>
+#endif
+
 /**
  * The rt_mutex structure
  *
@@ -31,12 +35,7 @@ struct rt_mutex {
        raw_spinlock_t          wait_lock;
        struct rb_root_cached   waiters;
        struct task_struct      *owner;
-#ifdef CONFIG_DEBUG_RT_MUTEXES
        int                     save_state;
-       const char              *name, *file;
-       int                     line;
-       void                    *magic;
-#endif
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
        struct lockdep_map      dep_map;
 #endif
@@ -49,6 +48,7 @@ struct hrtimer_sleeper;
  extern int rt_mutex_debug_check_no_locks_freed(const void *from,
                                                unsigned long len);
  extern void rt_mutex_debug_check_no_locks_held(struct task_struct *task);
+ extern void rt_mutex_debug_task_free(struct task_struct *tsk);
 #else
  static inline int rt_mutex_debug_check_no_locks_freed(const void *from,
                                                       unsigned long len)
@@ -56,25 +56,15 @@ struct hrtimer_sleeper;
        return 0;
  }
 # define rt_mutex_debug_check_no_locks_held(task)      do { } while (0)
+# define rt_mutex_debug_task_free(t)                   do { } while (0)
 #endif
 
-#ifdef CONFIG_DEBUG_RT_MUTEXES
-# define __DEBUG_RT_MUTEX_INITIALIZER(mutexname) \
-       , .name = #mutexname, .file = __FILE__, .line = __LINE__
-
-# define rt_mutex_init(mutex) \
+#define rt_mutex_init(mutex) \
 do { \
        static struct lock_class_key __key; \
        __rt_mutex_init(mutex, __func__, &__key); \
 } while (0)
 
- 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, NULL)
-# define rt_mutex_debug_task_free(t)                   do { } while (0)
-#endif
-
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 #define __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname) \
        , .dep_map = { .name = #mutexname }
@@ -82,12 +72,19 @@ do { \
 #define __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname)
 #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_CACHED \
        , .owner = NULL \
-       __DEBUG_RT_MUTEX_INITIALIZER(mutexname) \
-       __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname)}
+       __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname)
+
+#define __RT_MUTEX_INITIALIZER(mutexname) \
+       { __RT_MUTEX_INITIALIZER_PLAIN(mutexname) \
+       , .save_state = 0 }
+
+#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)
@@ -115,9 +112,6 @@ extern void rt_mutex_lock(struct rt_mutex *lock);
 #endif
 
 extern int rt_mutex_lock_interruptible(struct rt_mutex *lock);
-extern int rt_mutex_timed_lock(struct rt_mutex *lock,
-                              struct hrtimer_sleeper *timeout);
-
 extern int rt_mutex_trylock(struct rt_mutex *lock);
 
 extern void rt_mutex_unlock(struct rt_mutex *lock);
diff --git a/include/linux/rwlock_rt.h b/include/linux/rwlock_rt.h
new file mode 100644 (file)
index 0000000..aafdb0a
--- /dev/null
@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#ifndef __LINUX_RWLOCK_RT_H
+#define __LINUX_RWLOCK_RT_H
+
+#ifndef __LINUX_SPINLOCK_H
+#error Do not include directly. Use spinlock.h
+#endif
+
+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_read_trylock(rwlock_t *rwlock);
+extern void __lockfunc rt_write_unlock(rwlock_t *rwlock);
+extern void __lockfunc rt_read_unlock(rwlock_t *rwlock);
+extern int __lockfunc rt_read_can_lock(rwlock_t *rwlock);
+extern int __lockfunc rt_write_can_lock(rwlock_t *rwlock);
+extern void __rt_rwlock_init(rwlock_t *rwlock, char *name, struct lock_class_key *key);
+
+#define read_can_lock(rwlock)          rt_read_can_lock(rwlock)
+#define write_can_lock(rwlock)         rt_write_can_lock(rwlock)
+
+#define read_trylock(lock)     __cond_lock(lock, rt_read_trylock(lock))
+#define write_trylock(lock)    __cond_lock(lock, rt_write_trylock(lock))
+
+static inline int __write_trylock_rt_irqsave(rwlock_t *lock, unsigned long *flags)
+{
+       *flags = 0;
+       return rt_write_trylock(lock);
+}
+
+#define write_trylock_irqsave(lock, flags)             \
+       __cond_lock(lock, __write_trylock_rt_irqsave(lock, &(flags)))
+
+#define read_lock_irqsave(lock, flags)                 \
+       do {                                            \
+               typecheck(unsigned long, flags);        \
+               rt_read_lock(lock);                     \
+               flags = 0;                              \
+       } while (0)
+
+#define write_lock_irqsave(lock, flags)                        \
+       do {                                            \
+               typecheck(unsigned long, flags);        \
+               rt_write_lock(lock);                    \
+               flags = 0;                              \
+       } 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)
+
+#define rwlock_init(rwl)                               \
+do {                                                   \
+       static struct lock_class_key __key;             \
+                                                       \
+       __rt_rwlock_init(rwl, #rwl, &__key);            \
+} while (0)
+
+#endif
index 3bd03e1..0ad226b 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..4762391
--- /dev/null
@@ -0,0 +1,56 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#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
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define RW_DEP_MAP_INIT(lockname)     .dep_map = { .name = #lockname }
+#else
+# define RW_DEP_MAP_INIT(lockname)
+#endif
+
+typedef struct rt_rw_lock rwlock_t;
+
+#define __RW_LOCK_UNLOCKED(name) __RWLOCK_RT_INITIALIZER(name)
+
+#define DEFINE_RWLOCK(name) \
+       rwlock_t name = __RW_LOCK_UNLOCKED(name)
+
+/*
+ * A reader biased implementation primarily for CPU pinning.
+ *
+ * Can be selected as general replacement for the single reader RT rwlock
+ * variant
+ */
+struct rt_rw_lock {
+       struct rt_mutex         rtmutex;
+       atomic_t                readers;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+       struct lockdep_map      dep_map;
+#endif
+};
+
+#define READER_BIAS    (1U << 31)
+#define WRITER_BIAS    (1U << 30)
+
+#define __RWLOCK_RT_INITIALIZER(name)                                  \
+{                                                                      \
+       .readers = ATOMIC_INIT(READER_BIAS),                            \
+       .rtmutex = __RT_MUTEX_INITIALIZER_SAVE_STATE(name.rtmutex),     \
+       RW_DEP_MAP_INIT(name)                                           \
+}
+
+void __rwlock_biased_rt_init(struct rt_rw_lock *lock, const char *name,
+                            struct lock_class_key *key);
+
+#define rwlock_biased_rt_init(rwlock)                                  \
+       do {                                                            \
+               static struct lock_class_key __key;                     \
+                                                                       \
+               __rwlock_biased_rt_init((rwlock), #rwlock, &__key);     \
+       } while (0)
+
+#endif
diff --git a/include/linux/rwsem-rt.h b/include/linux/rwsem-rt.h
new file mode 100644 (file)
index 0000000..0ba8aae
--- /dev/null
@@ -0,0 +1,70 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#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_interruptible(struct rw_semaphore *sem);
+extern int __down_read_killable(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 4c715be..9323af8 100644 (file)
 #include <linux/spinlock.h>
 #include <linux/atomic.h>
 #include <linux/err.h>
+
+#ifdef CONFIG_PREEMPT_RT
+#include <linux/rwsem-rt.h>
+#else /* PREEMPT_RT */
+
 #ifdef CONFIG_RWSEM_SPIN_ON_OWNER
 #include <linux/osq_lock.h>
 #endif
@@ -119,6 +124,13 @@ static inline int rwsem_is_contended(struct rw_semaphore *sem)
        return !list_empty(&sem->wait_list);
 }
 
+#endif /* !PREEMPT_RT */
+
+/*
+ * The functions below are the same for all rwsem implementations including
+ * the RT specific variant.
+ */
+
 /*
  * lock for reading
  */
index b85b26d..29e6ff1 100644 (file)
@@ -34,6 +34,7 @@
 #include <linux/rseq.h>
 #include <linux/seqlock.h>
 #include <linux/kcsan.h>
+#include <asm/kmap_size.h>
 
 /* task_struct member predeclarations (sorted alphabetically): */
 struct audit_context;
@@ -111,12 +112,8 @@ struct io_uring_task;
                                         __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \
                                         TASK_PARKED)
 
-#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)
-
 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
 
 /*
@@ -140,6 +137,9 @@ struct io_uring_task;
                smp_store_mb(current->state, (state_value));    \
        } while (0)
 
+#define __set_current_state_no_track(state_value)              \
+       current->state = (state_value);
+
 #define set_special_state(state_value)                                 \
        do {                                                            \
                unsigned long flags; /* may shadow */                   \
@@ -193,6 +193,9 @@ struct io_uring_task;
 #define set_current_state(state_value)                                 \
        smp_store_mb(current->state, (state_value))
 
+#define __set_current_state_no_track(state_value)      \
+       __set_current_state(state_value)
+
 /*
  * set_special_state() should be used for those states when the blocking task
  * can not use the regular condition based wait-loop. In that case we must
@@ -645,6 +648,13 @@ struct wake_q_node {
        struct wake_q_node *next;
 };
 
+struct kmap_ctrl {
+#ifdef CONFIG_KMAP_LOCAL
+       int                             idx;
+       pte_t                           pteval[KM_MAX_IDX];
+#endif
+};
+
 struct task_struct {
 #ifdef CONFIG_THREAD_INFO_IN_TASK
        /*
@@ -655,6 +665,8 @@ struct task_struct {
 #endif
        /* -1 unrunnable, 0 runnable, >0 stopped: */
        volatile long                   state;
+       /* saved state for "spinlock sleepers" */
+       volatile long                   saved_state;
 
        /*
         * This begins the randomizable portion of task_struct. Only
@@ -730,6 +742,11 @@ struct task_struct {
        int                             nr_cpus_allowed;
        const cpumask_t                 *cpus_ptr;
        cpumask_t                       cpus_mask;
+       void                            *migration_pending;
+#ifdef CONFIG_SMP
+       unsigned short                  migration_disabled;
+#endif
+       unsigned short                  migration_flags;
 
 #ifdef CONFIG_PREEMPT_RCU
        int                             rcu_read_lock_nesting;
@@ -835,6 +852,10 @@ struct task_struct {
        /* Stalled due to lack of memory */
        unsigned                        in_memstall:1;
 #endif
+#ifdef CONFIG_EVENTFD
+       /* Recursion prevention for eventfd_signal() */
+       unsigned                        in_eventfd_signal:1;
+#endif
 
        unsigned long                   atomic_flags; /* Flags requiring atomic access. */
 
@@ -976,11 +997,16 @@ struct task_struct {
        /* Signal handlers: */
        struct signal_struct            *signal;
        struct sighand_struct __rcu             *sighand;
+       struct sigqueue                 *sigqueue_cache;
        sigset_t                        blocked;
        sigset_t                        real_blocked;
        /* Restored if set_restore_sigmask() was used: */
        sigset_t                        saved_sigmask;
        struct sigpending               pending;
+#ifdef CONFIG_PREEMPT_RT
+       /* TODO: move me into ->restart_block ? */
+       struct                          kernel_siginfo forced_info;
+#endif
        unsigned long                   sas_ss_sp;
        size_t                          sas_ss_size;
        unsigned int                    sas_ss_flags;
@@ -1007,6 +1033,7 @@ 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: */
@@ -1034,6 +1061,9 @@ struct task_struct {
        int                             softirq_context;
        int                             irq_config;
 #endif
+#ifdef CONFIG_PREEMPT_RT
+       int                             softirq_disable_cnt;
+#endif
 
 #ifdef CONFIG_LOCKDEP
 # define MAX_LOCK_DEPTH                        48UL
@@ -1319,6 +1349,7 @@ struct task_struct {
        unsigned int                    sequential_io;
        unsigned int                    sequential_io_avg;
 #endif
+       struct kmap_ctrl                kmap_ctrl;
 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
        unsigned long                   task_state_change;
 #endif
@@ -1764,6 +1795,7 @@ extern struct task_struct *find_get_task_by_vpid(pid_t nr);
 
 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
@@ -1854,6 +1886,89 @@ 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 bool __task_is_stopped_or_traced(struct task_struct *task)
+{
+       if (task->state & (__TASK_STOPPED | __TASK_TRACED))
+               return true;
+#ifdef CONFIG_PREEMPT_RT
+       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
+       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
+       /* 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
index 9a62ffd..412cdab 100644 (file)
@@ -11,8 +11,10 @@ extern int sched_cpu_activate(unsigned int cpu);
 extern int sched_cpu_deactivate(unsigned int cpu);
 
 #ifdef CONFIG_HOTPLUG_CPU
+extern int sched_cpu_wait_empty(unsigned int cpu);
 extern int sched_cpu_dying(unsigned int cpu);
 #else
+# define sched_cpu_wait_empty  NULL
 # define sched_cpu_dying       NULL
 #endif
 
index dc1f4dc..9796cc2 100644 (file)
@@ -49,6 +49,17 @@ static inline void mmdrop(struct mm_struct *mm)
                __mmdrop(mm);
 }
 
+#ifdef CONFIG_PREEMPT_RT
+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
+
 /**
  * mmget() - Pin the address space associated with a &struct mm_struct.
  * @mm: The address space to pin.
index e5af028..994c256 100644 (file)
@@ -39,20 +39,12 @@ static inline struct task_struct *rt_mutex_get_top_task(struct task_struct *p)
 }
 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 struct task_struct *rt_mutex_get_top_task(struct task_struct *task)
 {
        return NULL;
 }
 # define rt_mutex_adjust_pi(p)         do { } while (0)
-static inline bool tsk_is_pi_blocked(struct task_struct *tsk)
-{
-       return false;
-}
 #endif
 
 extern void normalize_rt_tasks(void);
index 26a2013..6e2dff7 100644 (file)
@@ -58,6 +58,17 @@ static inline bool wake_q_empty(struct wake_q_head *head)
 
 extern void wake_q_add(struct wake_q_head *head, struct task_struct *task);
 extern void wake_q_add_safe(struct wake_q_head *head, struct task_struct *task);
-extern void wake_up_q(struct wake_q_head *head);
+extern void wake_q_add_sleeper(struct wake_q_head *head, struct task_struct *task);
+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);
+}
 
 #endif /* _LINUX_SCHED_WAKE_Q_H */
index 2b70f73..68d7563 100644 (file)
@@ -7,6 +7,7 @@
 #ifndef _LINUX_SERIAL_8250_H
 #define _LINUX_SERIAL_8250_H
 
+#include <linux/atomic.h>
 #include <linux/serial_core.h>
 #include <linux/serial_reg.h>
 #include <linux/platform_device.h>
@@ -125,6 +126,8 @@ struct uart_8250_port {
 #define MSR_SAVE_FLAGS UART_MSR_ANY_DELTA
        unsigned char           msr_saved_flags;
 
+       atomic_t                console_printing;
+
        struct uart_8250_dma    *dma;
        const struct uart_8250_ops *ops;
 
@@ -180,6 +183,8 @@ void serial8250_init_port(struct uart_8250_port *up);
 void serial8250_set_defaults(struct uart_8250_port *up);
 void serial8250_console_write(struct uart_8250_port *up, const char *s,
                              unsigned int count);
+void serial8250_console_write_atomic(struct uart_8250_port *up, const char *s,
+                                    unsigned int count);
 int serial8250_console_setup(struct uart_port *port, char *options, bool probe);
 int serial8250_console_exit(struct uart_port *port);
 
index a5a5d1d..0470d15 100644 (file)
@@ -31,7 +31,7 @@ struct shmem_sb_info {
        struct percpu_counter used_blocks;  /* How many are allocated */
        unsigned long max_inodes;   /* How many inodes are allowed */
        unsigned long free_inodes;  /* How many are left for allocation */
-       spinlock_t stat_lock;       /* Serialize shmem_sb_info changes */
+       raw_spinlock_t stat_lock;   /* Serialize shmem_sb_info changes */
        umode_t mode;               /* Mount mode for root directory */
        unsigned char huge;         /* Whether to try for hugepages */
        kuid_t uid;                 /* Mount uid for root directory */
index b256f9c..ebf6c51 100644 (file)
@@ -265,6 +265,7 @@ 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 acbf187..9ebefda 100644 (file)
@@ -295,6 +295,7 @@ struct sk_buff_head {
 
        __u32           qlen;
        spinlock_t      lock;
+       raw_spinlock_t  raw_lock;
 };
 
 struct sk_buff;
@@ -1884,6 +1885,12 @@ 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 04f44e0..cae6681 100644 (file)
@@ -239,6 +239,9 @@ static inline int get_boot_cpu_id(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 7989784..c3c7029 100644 (file)
@@ -309,7 +309,11 @@ static inline void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock)
 })
 
 /* Include rwlock functions */
-#include <linux/rwlock.h>
+#ifdef CONFIG_PREEMPT_RT
+# include <linux/rwlock_rt.h>
+#else
+# include <linux/rwlock.h>
+#endif
 
 /*
  * Pull the _spin_*()/_read_*()/_write_*() functions/declarations:
@@ -320,6 +324,10 @@ static inline void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock)
 # include <linux/spinlock_api_up.h>
 #endif
 
+#ifdef CONFIG_PREEMPT_RT
+# include <linux/spinlock_rt.h>
+#else /* PREEMPT_RT */
+
 /*
  * Map the spin_lock functions to the raw variants for PREEMPT_RT=n
  */
@@ -454,6 +462,8 @@ static __always_inline int spin_is_contended(spinlock_t *lock)
 
 #define assert_spin_locked(lock)       assert_raw_spin_locked(&(lock)->rlock)
 
+#endif /* !PREEMPT_RT */
+
 /*
  * Pull the atomic_t declaration:
  * (asm-mips/atomic.h needs above definitions)
index 19a9be9..da38149 100644 (file)
@@ -187,6 +187,8 @@ static inline int __raw_spin_trylock_bh(raw_spinlock_t *lock)
        return 0;
 }
 
-#include <linux/rwlock_api_smp.h>
+#ifndef CONFIG_PREEMPT_RT
+# 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..3085132
--- /dev/null
@@ -0,0 +1,155 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#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, const 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)
+
+extern void __lockfunc rt_spin_lock(spinlock_t *lock);
+extern void __lockfunc rt_spin_lock_nested(spinlock_t *lock, int subclass);
+extern void __lockfunc rt_spin_lock_nest_lock(spinlock_t *lock, struct lockdep_map *nest_lock);
+extern void __lockfunc rt_spin_unlock(spinlock_t *lock);
+extern void __lockfunc rt_spin_lock_unlock(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.
+ * Migrate disable handling must be done at the call site.
+ */
+extern void __lockfunc __rt_spin_lock(struct rt_mutex *lock);
+extern void __lockfunc __rt_spin_trylock(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_nest_lock(lock, subclass)           \
+       do {                                                           \
+               typecheck(struct lockdep_map *, &(subclass)->dep_map);  \
+               rt_spin_lock_nest_lock(lock, &(subclass)->dep_map);     \
+       } 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(((void)(subclass), (lock)))
+# define spin_lock_nest_lock(lock, subclass)   spin_lock(((void)(subclass), (lock)))
+# define spin_lock_bh_nested(lock, subclass)   spin_lock_bh(((void)(subclass), (lock)))
+
+# define spin_lock_irqsave_nested(lock, flags, subclass) \
+       do {                                             \
+               typecheck(unsigned long, flags);         \
+               flags = 0;                               \
+               spin_lock(((void)(subclass), (lock)));   \
+       } while (0)
+#endif
+
+#define spin_lock_irqsave(lock, flags)                  \
+       do {                                             \
+               typecheck(unsigned long, flags);         \
+               flags = 0;                               \
+               spin_lock(lock);                         \
+       } while (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)              \
+({                                                     \
+       int __locked;                                   \
+                                                       \
+       typecheck(unsigned long, flags);                \
+       flags = 0;                                      \
+       __locked = spin_trylock(lock);                  \
+       __locked;                                       \
+})
+
+#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));
+}
+
+#endif
index b981caa..8d896d3 100644 (file)
@@ -9,93 +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_types.h>
-
-typedef struct raw_spinlock {
-       arch_spinlock_t raw_lock;
-#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 RAW_SPIN_DEP_MAP_INIT(lockname)               \
-       .dep_map = {                                    \
-               .name = #lockname,                      \
-               .wait_type_inner = LD_WAIT_SPIN,        \
-       }
-# define SPIN_DEP_MAP_INIT(lockname)                   \
-       .dep_map = {                                    \
-               .name = #lockname,                      \
-               .wait_type_inner = LD_WAIT_CONFIG,      \
-       }
-#else
-# define RAW_SPIN_DEP_MAP_INIT(lockname)
-# 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
+# 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)               \
-       RAW_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)     \
-       {                                       \
-       .raw_lock = __ARCH_SPIN_LOCK_UNLOCKED,  \
-       SPIN_DEBUG_INIT(lockname)               \
-       SPIN_DEP_MAP_INIT(lockname) }
-
-#define __SPIN_LOCK_INITIALIZER(lockname) \
-       { { .rlock = ___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..e4549f0
--- /dev/null
@@ -0,0 +1,39 @@
+#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)     \
+{                                              \
+       .raw_lock = __ARCH_SPIN_LOCK_UNLOCKED,  \
+       SPIN_DEBUG_INIT(lockname)               \
+       SPIN_DEP_MAP_INIT(lockname) }
+
+#define __SPIN_LOCK_INITIALIZER(lockname) \
+       { { .rlock = ___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..1d4a180
--- /dev/null
@@ -0,0 +1,65 @@
+#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_types.h>
+
+typedef struct raw_spinlock {
+       arch_spinlock_t raw_lock;
+#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 RAW_SPIN_DEP_MAP_INIT(lockname)               \
+       .dep_map = {                                    \
+               .name = #lockname,                      \
+               .wait_type_inner = LD_WAIT_SPIN,        \
+       }
+# define SPIN_DEP_MAP_INIT(lockname)                   \
+       .dep_map = {                                    \
+               .name = #lockname,                      \
+               .wait_type_inner = LD_WAIT_CONFIG,      \
+       }
+#else
+# define RAW_SPIN_DEP_MAP_INIT(lockname)
+# 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)               \
+       RAW_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..446da78
--- /dev/null
@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#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;
+
+#define __RT_SPIN_INITIALIZER(name) \
+       { \
+       .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(name.wait_lock), \
+       .save_state = 1, \
+       }
+/*
+.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 c09b640..d9b371f 100644 (file)
@@ -1,7 +1,7 @@
 #ifndef __LINUX_SPINLOCK_TYPES_UP_H
 #define __LINUX_SPINLOCK_TYPES_UP_H
 
-#ifndef __LINUX_SPINLOCK_TYPES_H
+#if !defined(__LINUX_SPINLOCK_TYPES_H) && !defined(__LINUX_RT_MUTEX_H)
 # error "please don't include this file directly"
 #endif
 
index 63ea9af..46fb3eb 100644 (file)
@@ -24,6 +24,7 @@ typedef int (*cpu_stop_fn_t)(void *arg);
 struct cpu_stop_work {
        struct list_head        list;           /* cpu_stopper->works */
        cpu_stop_fn_t           fn;
+       unsigned long           caller;
        void                    *arg;
        struct cpu_stop_done    *done;
 };
@@ -36,6 +37,8 @@ void stop_machine_park(int cpu);
 void stop_machine_unpark(int cpu);
 void stop_machine_yield(const struct cpumask *cpumask);
 
+extern void print_stop_info(const char *log_lvl, struct task_struct *task);
+
 #else  /* CONFIG_SMP */
 
 #include <linux/workqueue.h>
@@ -80,6 +83,8 @@ static inline bool stop_one_cpu_nowait(unsigned int cpu,
        return false;
 }
 
+static inline void print_stop_info(const char *log_lvl, struct task_struct *task) { }
+
 #endif /* CONFIG_SMP */
 
 /*
index f3040b0..3cb02ce 100644 (file)
@@ -110,7 +110,17 @@ 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 c57b793..3b3c9de 100644 (file)
@@ -67,6 +67,8 @@ struct trace_entry {
        unsigned char           flags;
        unsigned char           preempt_count;
        int                     pid;
+       unsigned char           migrate_disable;
+       unsigned char           preempt_lazy_count;
 };
 
 #define TRACE_EVENT_TYPE_MAX                                           \
@@ -148,17 +150,78 @@ enum print_line_t {
 
 enum print_line_t trace_handle_return(struct trace_seq *s);
 
-void tracing_generic_entry_update(struct trace_entry *entry,
-                                 unsigned short type,
-                                 unsigned long flags,
-                                 int pc);
+static inline void tracing_generic_entry_update(struct trace_entry *entry,
+                                               unsigned short type,
+                                               unsigned int trace_ctx)
+{
+       entry->preempt_count            = trace_ctx & 0xff;
+       entry->migrate_disable          = (trace_ctx >> 8) & 0xff;
+       entry->preempt_lazy_count       = (trace_ctx >> 16) & 0xff;
+       entry->pid                      = current->pid;
+       entry->type                     = type;
+       entry->flags                    = trace_ctx >> 24;
+}
+
+unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status);
+
+enum trace_flag_type {
+       TRACE_FLAG_IRQS_OFF             = 0x01,
+       TRACE_FLAG_IRQS_NOSUPPORT       = 0x02,
+       TRACE_FLAG_NEED_RESCHED         = 0x04,
+       TRACE_FLAG_HARDIRQ              = 0x08,
+       TRACE_FLAG_SOFTIRQ              = 0x10,
+       TRACE_FLAG_PREEMPT_RESCHED      = 0x20,
+       TRACE_FLAG_NMI                  = 0x40,
+       TRACE_FLAG_NEED_RESCHED_LAZY    = 0x80,
+};
+
+#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
+static inline unsigned int tracing_gen_ctx_flags(unsigned long irqflags)
+{
+       unsigned int irq_status = irqs_disabled_flags(irqflags) ?
+               TRACE_FLAG_IRQS_OFF : 0;
+       return tracing_gen_ctx_irq_test(irq_status);
+}
+static inline unsigned int tracing_gen_ctx(void)
+{
+       unsigned long irqflags;
+
+       local_save_flags(irqflags);
+       return tracing_gen_ctx_flags(irqflags);
+}
+#else
+
+static inline unsigned int tracing_gen_ctx_flags(unsigned long irqflags)
+{
+       return tracing_gen_ctx_irq_test(TRACE_FLAG_IRQS_NOSUPPORT);
+}
+static inline unsigned int tracing_gen_ctx(void)
+{
+       return tracing_gen_ctx_irq_test(TRACE_FLAG_IRQS_NOSUPPORT);
+}
+#endif
+
+static inline unsigned int tracing_gen_ctx_dec(void)
+{
+       unsigned int trace_ctx;
+
+       trace_ctx = tracing_gen_ctx();
+       /*
+        * Subtract one from the preeption counter if preemption is enabled,
+        * see trace_event_buffer_reserve()for details.
+        */
+       if (IS_ENABLED(CONFIG_PREEMPTION))
+               trace_ctx--;
+       return trace_ctx;
+}
+
 struct trace_event_file;
 
 struct ring_buffer_event *
 trace_event_buffer_lock_reserve(struct trace_buffer **current_buffer,
                                struct trace_event_file *trace_file,
                                int type, unsigned long len,
-                               unsigned long flags, int pc);
+                               unsigned int trace_ctx);
 
 #define TRACE_RECORD_CMDLINE   BIT(0)
 #define TRACE_RECORD_TGID      BIT(1)
@@ -232,8 +295,7 @@ struct trace_event_buffer {
        struct ring_buffer_event        *event;
        struct trace_event_file         *trace_file;
        void                            *entry;
-       unsigned long                   flags;
-       int                             pc;
+       unsigned int                    trace_ctx;
        struct pt_regs                  *regs;
 };
 
index e81856c..66eb968 100644 (file)
@@ -66,7 +66,7 @@
 #include <linux/seqlock.h>
 
 struct u64_stats_sync {
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+#if BITS_PER_LONG==32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
        seqcount_t      seq;
 #endif
 };
@@ -115,7 +115,7 @@ static inline void u64_stats_inc(u64_stats_t *p)
 }
 #endif
 
-#if BITS_PER_LONG == 32 && defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
 #define u64_stats_init(syncp)  seqcount_init(&(syncp)->seq)
 #else
 static inline void u64_stats_init(struct u64_stats_sync *syncp)
@@ -125,15 +125,19 @@ static inline void u64_stats_init(struct u64_stats_sync *syncp)
 
 static inline void u64_stats_update_begin(struct u64_stats_sync *syncp)
 {
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
+       if (IS_ENABLED(CONFIG_PREEMPT_RT))
+               preempt_disable();
        write_seqcount_begin(&syncp->seq);
 #endif
 }
 
 static inline void u64_stats_update_end(struct u64_stats_sync *syncp)
 {
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
        write_seqcount_end(&syncp->seq);
+       if (IS_ENABLED(CONFIG_PREEMPT_RT))
+               preempt_enable();
 #endif
 }
 
@@ -142,8 +146,11 @@ u64_stats_update_begin_irqsave(struct u64_stats_sync *syncp)
 {
        unsigned long flags = 0;
 
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
-       local_irq_save(flags);
+#if BITS_PER_LONG == 32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
+       if (IS_ENABLED(CONFIG_PREEMPT_RT))
+               preempt_disable();
+       else
+               local_irq_save(flags);
        write_seqcount_begin(&syncp->seq);
 #endif
        return flags;
@@ -153,15 +160,18 @@ static inline void
 u64_stats_update_end_irqrestore(struct u64_stats_sync *syncp,
                                unsigned long flags)
 {
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
        write_seqcount_end(&syncp->seq);
-       local_irq_restore(flags);
+       if (IS_ENABLED(CONFIG_PREEMPT_RT))
+               preempt_enable();
+       else
+               local_irq_restore(flags);
 #endif
 }
 
 static inline unsigned int __u64_stats_fetch_begin(const struct u64_stats_sync *syncp)
 {
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
        return read_seqcount_begin(&syncp->seq);
 #else
        return 0;
@@ -170,7 +180,7 @@ static inline unsigned int __u64_stats_fetch_begin(const struct u64_stats_sync *
 
 static inline unsigned int u64_stats_fetch_begin(const struct u64_stats_sync *syncp)
 {
-#if BITS_PER_LONG==32 && !defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (!defined(CONFIG_SMP) && !defined(CONFIG_PREEMPT_RT))
        preempt_disable();
 #endif
        return __u64_stats_fetch_begin(syncp);
@@ -179,7 +189,7 @@ static inline unsigned int u64_stats_fetch_begin(const struct u64_stats_sync *sy
 static inline bool __u64_stats_fetch_retry(const struct u64_stats_sync *syncp,
                                         unsigned int start)
 {
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT))
        return read_seqcount_retry(&syncp->seq, start);
 #else
        return false;
@@ -189,7 +199,7 @@ static inline bool __u64_stats_fetch_retry(const struct u64_stats_sync *syncp,
 static inline bool u64_stats_fetch_retry(const struct u64_stats_sync *syncp,
                                         unsigned int start)
 {
-#if BITS_PER_LONG==32 && !defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && (!defined(CONFIG_SMP) && !defined(CONFIG_PREEMPT_RT))
        preempt_enable();
 #endif
        return __u64_stats_fetch_retry(syncp, start);
@@ -203,7 +213,9 @@ static inline bool u64_stats_fetch_retry(const struct u64_stats_sync *syncp,
  */
 static inline unsigned int u64_stats_fetch_begin_irq(const struct u64_stats_sync *syncp)
 {
-#if BITS_PER_LONG==32 && !defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && defined(CONFIG_PREEMPT_RT)
+       preempt_disable();
+#elif BITS_PER_LONG == 32 && !defined(CONFIG_SMP)
        local_irq_disable();
 #endif
        return __u64_stats_fetch_begin(syncp);
@@ -212,7 +224,9 @@ static inline unsigned int u64_stats_fetch_begin_irq(const struct u64_stats_sync
 static inline bool u64_stats_fetch_retry_irq(const struct u64_stats_sync *syncp,
                                             unsigned int start)
 {
-#if BITS_PER_LONG==32 && !defined(CONFIG_SMP)
+#if BITS_PER_LONG == 32 && defined(CONFIG_PREEMPT_RT)
+       preempt_enable();
+#elif BITS_PER_LONG == 32 && !defined(CONFIG_SMP)
        local_irq_enable();
 #endif
        return __u64_stats_fetch_retry(syncp, start);
index 322dcbf..9a3a10e 100644 (file)
@@ -63,7 +63,9 @@ 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)
@@ -73,7 +75,9 @@ 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 2cdeca0..041d652 100644 (file)
@@ -83,36 +83,46 @@ static inline void vtime_init_idle(struct task_struct *tsk, int cpu) { }
 #endif
 
 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
-extern void vtime_account_irq_enter(struct task_struct *tsk);
-static inline void vtime_account_irq_exit(struct task_struct *tsk)
-{
-       /* On hard|softirq exit we always account to hard|softirq cputime */
-       vtime_account_kernel(tsk);
-}
+extern void vtime_account_irq(struct task_struct *tsk, unsigned int offset);
+extern void vtime_account_softirq(struct task_struct *tsk);
+extern void vtime_account_hardirq(struct task_struct *tsk);
 extern void vtime_flush(struct task_struct *tsk);
 #else /* !CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */
-static inline void vtime_account_irq_enter(struct task_struct *tsk) { }
-static inline void vtime_account_irq_exit(struct task_struct *tsk) { }
+static inline void vtime_account_irq(struct task_struct *tsk, unsigned int offset) { }
+static inline void vtime_account_softirq(struct task_struct *tsk) { }
+static inline void vtime_account_hardirq(struct task_struct *tsk) { }
 static inline void vtime_flush(struct task_struct *tsk) { }
 #endif
 
 
 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
-extern void irqtime_account_irq(struct task_struct *tsk);
+extern void irqtime_account_irq(struct task_struct *tsk, unsigned int offset);
 #else
-static inline void irqtime_account_irq(struct task_struct *tsk) { }
+static inline void irqtime_account_irq(struct task_struct *tsk, unsigned int offset) { }
 #endif
 
-static inline void account_irq_enter_time(struct task_struct *tsk)
+static inline void account_softirq_enter(struct task_struct *tsk)
+{
+       vtime_account_irq(tsk, SOFTIRQ_OFFSET);
+       irqtime_account_irq(tsk, SOFTIRQ_OFFSET);
+}
+
+static inline void account_softirq_exit(struct task_struct *tsk)
+{
+       vtime_account_softirq(tsk);
+       irqtime_account_irq(tsk, 0);
+}
+
+static inline void account_hardirq_enter(struct task_struct *tsk)
 {
-       vtime_account_irq_enter(tsk);
-       irqtime_account_irq(tsk);
+       vtime_account_irq(tsk, HARDIRQ_OFFSET);
+       irqtime_account_irq(tsk, HARDIRQ_OFFSET);
 }
 
-static inline void account_irq_exit_time(struct task_struct *tsk)
+static inline void account_hardirq_exit(struct task_struct *tsk)
 {
-       vtime_account_irq_exit(tsk);
-       irqtime_account_irq(tsk);
+       vtime_account_hardirq(tsk);
+       irqtime_account_irq(tsk, 0);
 }
 
 #endif /* _LINUX_KERNEL_VTIME_H */
index 9b8b083..33001b5 100644 (file)
@@ -10,6 +10,7 @@
 
 #include <asm/current.h>
 #include <uapi/linux/wait.h>
+#include <linux/atomic.h>
 
 typedef struct wait_queue_entry wait_queue_entry_t;
 
index 6ecf2a0..3145de5 100644 (file)
@@ -28,6 +28,14 @@ struct ww_class {
        unsigned int is_wait_die;
 };
 
+struct ww_mutex {
+       struct mutex base;
+       struct ww_acquire_ctx *ctx;
+#ifdef CONFIG_DEBUG_MUTEXES
+       struct ww_class *ww_class;
+#endif
+};
+
 struct ww_acquire_ctx {
        struct task_struct *task;
        unsigned long stamp;
index 1424e02..163f841 100644 (file)
@@ -6,6 +6,7 @@
 #include <linux/socket.h>
 #include <linux/rtnetlink.h>
 #include <linux/pkt_sched.h>
+#include <net/net_seq_lock.h>
 
 /* Note: this used to be in include/uapi/linux/gen_stats.h */
 struct gnet_stats_basic_packed {
@@ -42,15 +43,15 @@ 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);
-int gnet_stats_copy_basic_hw(const seqcount_t *running,
+int gnet_stats_copy_basic_hw(net_seqlock_t *running,
                             struct gnet_dump *d,
                             struct gnet_stats_basic_cpu __percpu *cpu,
                             struct gnet_stats_basic_packed *b);
@@ -70,13 +71,13 @@ int gen_new_estimator(struct gnet_stats_basic_packed *bstats,
                      struct gnet_stats_basic_cpu __percpu *cpu_bstats,
                      struct net_rate_estimator __rcu **rate_est,
                      spinlock_t *lock,
-                     seqcount_t *running, struct nlattr *opt);
+                     net_seqlock_t *running, struct nlattr *opt);
 void gen_kill_estimator(struct net_rate_estimator __rcu **ptr);
 int gen_replace_estimator(struct gnet_stats_basic_packed *bstats,
                          struct gnet_stats_basic_cpu __percpu *cpu_bstats,
                          struct net_rate_estimator __rcu **ptr,
                          spinlock_t *lock,
-                         seqcount_t *running, struct nlattr *opt);
+                         net_seqlock_t *running, struct nlattr *opt);
 bool gen_estimator_active(struct net_rate_estimator __rcu **ptr);
 bool gen_estimator_read(struct net_rate_estimator __rcu **ptr,
                        struct gnet_stats_rate_est64 *sample);
diff --git a/include/net/net_seq_lock.h b/include/net/net_seq_lock.h
new file mode 100644 (file)
index 0000000..67710ba
--- /dev/null
@@ -0,0 +1,15 @@
+#ifndef __NET_NET_SEQ_LOCK_H__
+#define __NET_NET_SEQ_LOCK_H__
+
+#ifdef CONFIG_PREEMPT_RT
+# 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 22e1bc7..9b376b8 100644 (file)
@@ -73,7 +73,7 @@ struct netns_xfrm {
        struct dst_ops          xfrm6_dst_ops;
 #endif
        spinlock_t              xfrm_state_lock;
-       seqcount_t              xfrm_state_hash_generation;
+       seqcount_spinlock_t     xfrm_state_hash_generation;
        seqcount_spinlock_t     xfrm_policy_hash_generation;
 
        spinlock_t xfrm_policy_lock;
index 1042c44..092f75d 100644 (file)
@@ -10,6 +10,7 @@
 #include <linux/percpu.h>
 #include <linux/dynamic_queue_limits.h>
 #include <linux/list.h>
+#include <net/net_seq_lock.h>
 #include <linux/refcount.h>
 #include <linux/workqueue.h>
 #include <linux/mutex.h>
@@ -101,7 +102,7 @@ struct Qdisc {
        struct sk_buff_head     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;
@@ -142,7 +143,11 @@ static inline bool qdisc_is_running(struct Qdisc *qdisc)
 {
        if (qdisc->flags & TCQ_F_NOLOCK)
                return spin_is_locked(&qdisc->seqlock);
+#ifdef CONFIG_PREEMPT_RT
+       return spin_is_locked(&qdisc->running.lock) ? true : false;
+#else
        return (raw_read_seqcount(&qdisc->running) & 1) ? true : false;
+#endif
 }
 
 static inline bool qdisc_is_percpu_stats(const struct Qdisc *q)
@@ -203,17 +208,35 @@ nolock_empty:
        } else if (qdisc_is_running(qdisc)) {
                return false;
        }
+#ifdef CONFIG_PREEMPT_RT
+       if (spin_trylock(&qdisc->running.lock)) {
+               seqcount_t *s = &qdisc->running.seqcount.seqcount;
+               /*
+                * Variant of write_seqcount_t_begin() telling lockdep that a
+                * trylock was attempted.
+                */
+               raw_write_seqcount_t_begin(s);
+               seqcount_acquire(&s->dep_map, 0, 1, _RET_IP_);
+               return true;
+       }
+       return false;
+#else
        /* Variant of write_seqcount_begin() telling lockdep a trylock
         * was attempted.
         */
        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
+       write_sequnlock(&qdisc->running);
+#else
        write_seqcount_end(&qdisc->running);
+#endif
        if (qdisc->flags & TCQ_F_NOLOCK) {
                spin_unlock(&qdisc->seqlock);
 
@@ -597,7 +620,7 @@ 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);
 
index c96a433..e48f584 100644 (file)
@@ -650,6 +650,18 @@ DECLARE_TRACE(sched_update_nr_running_tp,
        TP_PROTO(struct rq *rq, int change),
        TP_ARGS(rq, change));
 
+DECLARE_TRACE(sched_migrate_disable_tp,
+             TP_PROTO(struct task_struct *p),
+             TP_ARGS(p));
+
+DECLARE_TRACE(sched_migrate_enable_tp,
+             TP_PROTO(struct task_struct *p),
+             TP_ARGS(p));
+
+DECLARE_TRACE(sched_migrate_pull_tp,
+             TP_PROTO(struct task_struct *p),
+             TP_ARGS(p));
+
 #endif /* _TRACE_SCHED_H */
 
 /* This part must be outside protection */
index 13685bf..ceda84b 100644 (file)
@@ -861,7 +861,7 @@ config NUMA_BALANCING
        bool "Memory placement aware NUMA scheduler"
        depends on ARCH_SUPPORTS_NUMA_BALANCING
        depends on !ARCH_WANT_NUMA_VARIABLE_LOCALITY
-       depends on SMP && NUMA && MIGRATION
+       depends on SMP && NUMA && MIGRATION && !PREEMPT_RT
        help
          This option adds support for automatic NUMA aware memory/task placement.
          The mechanism is quite primitive and is based on migrating memory when
@@ -968,6 +968,7 @@ config CFS_BANDWIDTH
 config RT_GROUP_SCHED
        bool "Group scheduling for SCHED_RR/FIFO"
        depends on CGROUP_SCHED
+       depends on !PREEMPT_RT
        default n
        help
          This feature lets you explicitly allocate real CPU bandwidth
@@ -1905,6 +1906,7 @@ choice
 
 config SLAB
        bool "SLAB"
+       depends on !PREEMPT_RT
        select HAVE_HARDENED_USERCOPY_ALLOCATOR
        help
          The regular slab allocator that is established and known to work
@@ -1925,6 +1927,7 @@ config SLUB
 config SLOB
        depends on EXPERT
        bool "SLOB (Simple Allocator)"
+       depends on !PREEMPT_RT
        help
           SLOB replaces the stock allocator with a drastically simpler
           allocator. SLOB is generally more space efficient but
@@ -1991,7 +1994,7 @@ config SHUFFLE_PAGE_ALLOCATOR
 
 config SLUB_CPU_PARTIAL
        default y
-       depends on SLUB && SMP
+       depends on SLUB && SMP && !PREEMPT_RT
        bool "SLUB per cpu partial cache"
        help
          Per cpu partial caches accelerate objects allocation and freeing
index 3de8fd1..4198f02 100644 (file)
@@ -251,7 +251,7 @@ config ARCH_USE_QUEUED_RWLOCKS
 
 config QUEUED_RWLOCKS
        def_bool y if ARCH_USE_QUEUED_RWLOCKS
-       depends on SMP
+       depends on SMP && !PREEMPT_RT
 
 config ARCH_HAS_MMIOWB
        bool
index bf82259..b5cd1e2 100644 (file)
@@ -1,5 +1,11 @@
 # SPDX-License-Identifier: GPL-2.0-only
 
+config HAVE_PREEMPT_LAZY
+       bool
+
+config PREEMPT_LAZY
+       def_bool y if HAVE_PREEMPT_LAZY && PREEMPT_RT
+
 choice
        prompt "Preemption Model"
        default PREEMPT_NONE
@@ -59,6 +65,7 @@ config PREEMPT_RT
        bool "Fully Preemptible Kernel (Real-Time)"
        depends on EXPERT && ARCH_SUPPORTS_RT
        select PREEMPTION
+       select RT_MUTEXES
        help
          This option turns the kernel into a real-time kernel by replacing
          various locking primitives (spinlocks, rwlocks, etc.) with
index 7c7758a..4a96ab6 100644 (file)
@@ -345,7 +345,7 @@ void cpuset_read_unlock(void)
        percpu_up_read(&cpuset_rwsem);
 }
 
-static DEFINE_SPINLOCK(callback_lock);
+static DEFINE_RAW_SPINLOCK(callback_lock);
 
 static struct workqueue_struct *cpuset_migrate_mm_wq;
 
@@ -1282,7 +1282,7 @@ static int update_parent_subparts_cpumask(struct cpuset *cpuset, int cmd,
         * Newly added CPUs will be removed from effective_cpus and
         * newly deleted ones will be added back to effective_cpus.
         */
-       spin_lock_irq(&callback_lock);
+       raw_spin_lock_irq(&callback_lock);
        if (adding) {
                cpumask_or(parent->subparts_cpus,
                           parent->subparts_cpus, tmp->addmask);
@@ -1304,7 +1304,7 @@ static int update_parent_subparts_cpumask(struct cpuset *cpuset, int cmd,
 
        if (cpuset->partition_root_state != new_prs)
                cpuset->partition_root_state = new_prs;
-       spin_unlock_irq(&callback_lock);
+       raw_spin_unlock_irq(&callback_lock);
 
        return cmd == partcmd_update;
 }
@@ -1407,7 +1407,7 @@ static void update_cpumasks_hier(struct cpuset *cs, struct tmpmasks *tmp)
                        continue;
                rcu_read_unlock();
 
-               spin_lock_irq(&callback_lock);
+               raw_spin_lock_irq(&callback_lock);
 
                cpumask_copy(cp->effective_cpus, tmp->new_cpus);
                if (cp->nr_subparts_cpus && (new_prs != PRS_ENABLED)) {
@@ -1441,7 +1441,7 @@ static void update_cpumasks_hier(struct cpuset *cs, struct tmpmasks *tmp)
                if (new_prs != cp->partition_root_state)
                        cp->partition_root_state = new_prs;
 
-               spin_unlock_irq(&callback_lock);
+               raw_spin_unlock_irq(&callback_lock);
 
                WARN_ON(!is_in_v2_mode() &&
                        !cpumask_equal(cp->cpus_allowed, cp->effective_cpus));
@@ -1559,7 +1559,7 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs,
                        return -EINVAL;
        }
 
-       spin_lock_irq(&callback_lock);
+       raw_spin_lock_irq(&callback_lock);
        cpumask_copy(cs->cpus_allowed, trialcs->cpus_allowed);
 
        /*
@@ -1569,7 +1569,7 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs,
                cpumask_and(cs->subparts_cpus, cs->subparts_cpus, cs->cpus_allowed);
                cs->nr_subparts_cpus = cpumask_weight(cs->subparts_cpus);
        }
-       spin_unlock_irq(&callback_lock);
+       raw_spin_unlock_irq(&callback_lock);
 
        update_cpumasks_hier(cs, &tmp);
 
@@ -1763,9 +1763,9 @@ 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(!is_in_v2_mode() &&
                        !nodes_equal(cp->mems_allowed, cp->effective_mems));
@@ -1833,9 +1833,9 @@ 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);
@@ -1926,9 +1926,9 @@ 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();
@@ -2019,9 +2019,9 @@ static int update_prstate(struct cpuset *cs, int new_prs)
        rebuild_sched_domains_locked();
 out:
        if (!err) {
-               spin_lock_irq(&callback_lock);
+               raw_spin_lock_irq(&callback_lock);
                cs->partition_root_state = new_prs;
-               spin_unlock_irq(&callback_lock);
+               raw_spin_unlock_irq(&callback_lock);
        }
 
        free_cpumasks(NULL, &tmpmask);
@@ -2437,7 +2437,7 @@ 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:
@@ -2459,7 +2459,7 @@ 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;
 }
 
@@ -2772,14 +2772,14 @@ static int cpuset_css_online(struct cgroup_subsys_state *css)
 
        cpuset_inc();
 
-       spin_lock_irq(&callback_lock);
+       raw_spin_lock_irq(&callback_lock);
        if (is_in_v2_mode()) {
                cpumask_copy(cs->effective_cpus, parent->effective_cpus);
                cs->effective_mems = parent->effective_mems;
                cs->use_parent_ecpus = true;
                parent->child_ecpus_count++;
        }
-       spin_unlock_irq(&callback_lock);
+       raw_spin_unlock_irq(&callback_lock);
 
        if (!test_bit(CGRP_CPUSET_CLONE_CHILDREN, &css->cgroup->flags))
                goto out_unlock;
@@ -2806,12 +2806,12 @@ 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->effective_cpus, parent->cpus_allowed);
-       spin_unlock_irq(&callback_lock);
+       raw_spin_unlock_irq(&callback_lock);
 out_unlock:
        percpu_up_write(&cpuset_rwsem);
        put_online_cpus();
@@ -2867,7 +2867,7 @@ static void cpuset_css_free(struct cgroup_subsys_state *css)
 static void cpuset_bind(struct cgroup_subsys_state *root_css)
 {
        percpu_down_write(&cpuset_rwsem);
-       spin_lock_irq(&callback_lock);
+       raw_spin_lock_irq(&callback_lock);
 
        if (is_in_v2_mode()) {
                cpumask_copy(top_cpuset.cpus_allowed, cpu_possible_mask);
@@ -2878,7 +2878,7 @@ 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);
        percpu_up_write(&cpuset_rwsem);
 }
 
@@ -2975,12 +2975,12 @@ 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,
@@ -3017,10 +3017,10 @@ 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);
@@ -3087,10 +3087,10 @@ retry:
        if (is_partition_root(cs) && (cpumask_empty(&new_cpus) ||
           (parent->partition_root_state == PRS_ERROR))) {
                if (cs->nr_subparts_cpus) {
-                       spin_lock_irq(&callback_lock);
+                       raw_spin_lock_irq(&callback_lock);
                        cs->nr_subparts_cpus = 0;
                        cpumask_clear(cs->subparts_cpus);
-                       spin_unlock_irq(&callback_lock);
+                       raw_spin_unlock_irq(&callback_lock);
                        compute_effective_cpumask(&new_cpus, cs, parent);
                }
 
@@ -3104,9 +3104,9 @@ retry:
                     cpumask_empty(&new_cpus)) {
                        update_parent_subparts_cpumask(cs, partcmd_disable,
                                                       NULL, tmp);
-                       spin_lock_irq(&callback_lock);
+                       raw_spin_lock_irq(&callback_lock);
                        cs->partition_root_state = PRS_ERROR;
-                       spin_unlock_irq(&callback_lock);
+                       raw_spin_unlock_irq(&callback_lock);
                }
                cpuset_force_rebuild();
        }
@@ -3186,7 +3186,7 @@ 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);
                /*
@@ -3206,17 +3206,17 @@ static void cpuset_hotplug_workfn(struct work_struct *work)
                        }
                }
                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);
        }
 
@@ -3317,11 +3317,11 @@ 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);
 }
 
 /**
@@ -3382,11 +3382,11 @@ 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;
 }
@@ -3478,14 +3478,14 @@ 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 89ca9b6..753dc34 100644 (file)
@@ -149,8 +149,9 @@ static void cgroup_rstat_flush_locked(struct cgroup *cgrp, bool may_sleep)
                raw_spinlock_t *cpu_lock = per_cpu_ptr(&cgroup_rstat_cpu_lock,
                                                       cpu);
                struct cgroup *pos = NULL;
+               unsigned long flags;
 
-               raw_spin_lock(cpu_lock);
+               raw_spin_lock_irqsave(cpu_lock, flags);
                while ((pos = cgroup_rstat_cpu_pop_updated(pos, cgrp, cpu))) {
                        struct cgroup_subsys_state *css;
 
@@ -162,7 +163,7 @@ static void cgroup_rstat_flush_locked(struct cgroup *cgrp, bool may_sleep)
                                css->ss->css_rstat_flush(css, cpu);
                        rcu_read_unlock();
                }
-               raw_spin_unlock(cpu_lock);
+               raw_spin_unlock_irqrestore(cpu_lock, flags);
 
                /* if @may_sleep, play nice and yield if necessary */
                if (may_sleep && (need_resched() ||
index c06ced1..10b6287 100644 (file)
@@ -1662,7 +1662,7 @@ static struct cpuhp_step cpuhp_hp_states[] = {
                .name                   = "ap:online",
        },
        /*
-        * Handled on controll processor until the plugged processor manages
+        * Handled on control processor until the plugged processor manages
         * this itself.
         */
        [CPUHP_TEARDOWN_CPU] = {
@@ -1671,6 +1671,13 @@ static struct cpuhp_step cpuhp_hp_states[] = {
                .teardown.single        = takedown_cpu,
                .cant_stop              = true,
        },
+
+       [CPUHP_AP_SCHED_WAIT_EMPTY] = {
+               .name                   = "sched:waitempty",
+               .startup.single         = NULL,
+               .teardown.single        = sched_cpu_wait_empty,
+       },
+
        /* Handle smpboot threads park/unpark */
        [CPUHP_AP_SMPBOOT_THREADS] = {
                .name                   = "smpboot/threads:online",
index 930ac1b..dbf1d12 100644 (file)
@@ -2101,7 +2101,7 @@ static int kdb_dmesg(int argc, const char **argv)
        int adjust = 0;
        int n = 0;
        int skip = 0;
-       struct kmsg_dumper dumper = { .active = 1 };
+       struct kmsg_dumper_iter iter = { .active = 1 };
        size_t len;
        char buf[201];
 
@@ -2126,8 +2126,8 @@ static int kdb_dmesg(int argc, const char **argv)
                kdb_set(2, setargs);
        }
 
-       kmsg_dump_rewind_nolock(&dumper);
-       while (kmsg_dump_get_line_nolock(&dumper, 1, NULL, 0, NULL))
+       kmsg_dump_rewind(&iter);
+       while (kmsg_dump_get_line(&iter, 1, NULL, 0, NULL))
                n++;
 
        if (lines < 0) {
@@ -2159,8 +2159,8 @@ static int kdb_dmesg(int argc, const char **argv)
        if (skip >= n || skip < 0)
                return 0;
 
-       kmsg_dump_rewind_nolock(&dumper);
-       while (kmsg_dump_get_line_nolock(&dumper, 1, buf, sizeof(buf), &len)) {
+       kmsg_dump_rewind(&iter);
+       while (kmsg_dump_get_line(&iter, 1, buf, sizeof(buf), &len)) {
                if (skip) {
                        skip--;
                        continue;
index e289e67..e73fcc5 100644 (file)
@@ -2,6 +2,7 @@
 
 #include <linux/context_tracking.h>
 #include <linux/entry-common.h>
+#include <linux/highmem.h>
 #include <linux/livepatch.h>
 #include <linux/audit.h>
 
@@ -148,9 +149,17 @@ static unsigned long exit_to_user_mode_loop(struct pt_regs *regs,
 
                local_irq_enable_exit_to_user(ti_work);
 
-               if (ti_work & _TIF_NEED_RESCHED)
+               if (ti_work & _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);
+                       t->forced_info.si_signo = 0;
+               }
+#endif
+
                if (ti_work & _TIF_UPROBE)
                        uprobe_notify_resume(regs);
 
@@ -194,6 +203,7 @@ static void exit_to_user_mode_prepare(struct pt_regs *regs)
 
        /* Ensure that the address limit is intact and no locks are held */
        addr_limit_user_check();
+       kmap_assert_nomap();
        lockdep_assert_irqs_disabled();
        lockdep_sys_exit();
 }
@@ -353,7 +363,7 @@ void irqentry_exit_cond_resched(void)
                rcu_irq_exit_check_preempt();
                if (IS_ENABLED(CONFIG_DEBUG_ENTRY))
                        WARN_ON_ONCE(!on_thread_stack());
-               if (need_resched())
+               if (should_resched(0))
                        preempt_schedule_irq();
        }
 }
index d13d67f..f5933bd 100644 (file)
@@ -152,7 +152,7 @@ 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 e465903..bc8f048 100644 (file)
@@ -42,6 +42,7 @@
 #include <linux/mmu_notifier.h>
 #include <linux/fs.h>
 #include <linux/mm.h>
+#include <linux/kprobes.h>
 #include <linux/vmacache.h>
 #include <linux/nsproxy.h>
 #include <linux/capability.h>
@@ -288,7 +289,7 @@ static inline void free_thread_stack(struct task_struct *tsk)
                        return;
                }
 
-               vfree_atomic(tsk->stack);
+               vfree(tsk->stack);
                return;
        }
 #endif
@@ -688,6 +689,19 @@ void __mmdrop(struct mm_struct *mm)
 }
 EXPORT_SYMBOL_GPL(__mmdrop);
 
+#ifdef CONFIG_PREEMPT_RT
+/*
+ * 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 void mmdrop_async_fn(struct work_struct *work)
 {
        struct mm_struct *mm;
@@ -729,6 +743,15 @@ void __put_task_struct(struct task_struct *tsk)
        WARN_ON(refcount_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);
+
        io_uring_free(tsk);
        cgroup_free(tsk);
        task_numa_free(tsk, true);
@@ -926,10 +949,12 @@ 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);
 
        kcov_task_init(tsk);
+       kmap_local_fork(tsk);
 
 #ifdef CONFIG_FAULT_INJECTION
        tsk->fail_nth = 0;
@@ -2001,6 +2026,7 @@ 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;
 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
index 98a6e1b..b2b275b 100644 (file)
@@ -1498,6 +1498,7 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_pi_state *pi_
        struct task_struct *new_owner;
        bool postunlock = false;
        DEFINE_WAKE_Q(wake_q);
+       DEFINE_WAKE_Q(wake_sleeper_q);
        int ret = 0;
 
        new_owner = rt_mutex_next_owner(&pi_state->pi_mutex);
@@ -1547,14 +1548,15 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_pi_state *pi_
                 * not fail.
                 */
                pi_state_update_owner(pi_state, new_owner);
-               postunlock = __rt_mutex_futex_unlock(&pi_state->pi_mutex, &wake_q);
+               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);
 
        if (postunlock)
-               rt_mutex_postunlock(&wake_q);
+               rt_mutex_postunlock(&wake_q, &wake_sleeper_q);
 
        return ret;
 }
@@ -2155,6 +2157,16 @@ retry_private:
                                 */
                                requeue_pi_wake_futex(this, &key2, hb2);
                                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
@@ -2847,7 +2859,7 @@ retry_private:
                goto no_block;
        }
 
-       rt_mutex_init_waiter(&rt_waiter);
+       rt_mutex_init_waiter(&rt_waiter, false);
 
        /*
         * On PREEMPT_RT_FULL, when hb->lock becomes an rt_mutex, we must not
@@ -3172,7 +3184,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
 {
        struct hrtimer_sleeper timeout, *to;
        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;
@@ -3193,7 +3205,7 @@ 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.
         */
-       rt_mutex_init_waiter(&rt_waiter);
+       rt_mutex_init_waiter(&rt_waiter, false);
 
        ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2, FUTEX_WRITE);
        if (unlikely(ret != 0))
@@ -3224,20 +3236,55 @@ 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;
+       /*
+        * 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;
+       }
 
        /*
-        * 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) {
@@ -3246,14 +3293,15 @@ 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);
                        /*
                         * 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);
                        /*
                         * Adjust the return value. It's either -EFAULT or
                         * success (1) but the caller expects 0 for success.
@@ -3272,7 +3320,8 @@ 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;
 
index 762a928..7929fcd 100644 (file)
@@ -192,10 +192,16 @@ 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
+       desc->random_ip = ip;
+#else
+       add_interrupt_randomness(desc->irq_data.irq, flags, ip);
+#endif
 
        if (!noirqdebug)
                note_interrupt(desc, retval);
index 79dc02b..de00a05 100644 (file)
@@ -1159,6 +1159,8 @@ static int irq_thread(void *data)
        irqreturn_t (*handler_fn)(struct irq_desc *desc,
                        struct irqaction *action);
 
+       sched_set_fifo(current);
+
        if (force_irqthreads && test_bit(IRQTF_FORCED_THREAD,
                                        &action->thread_flags))
                handler_fn = irq_forced_thread_fn;
@@ -1179,6 +1181,12 @@ static int irq_thread(void *data)
                if (action_ret == IRQ_WAKE_THREAD)
                        irq_wake_secondary(desc, action);
 
+               if (IS_ENABLED(CONFIG_PREEMPT_RT)) {
+                       migrate_disable();
+                       add_interrupt_randomness(action->irq, 0,
+                                desc->random_ip ^ (unsigned long) action);
+                       migrate_enable();
+               }
                wake_threads_waitq(desc);
        }
 
@@ -1324,8 +1332,6 @@ setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary)
        if (IS_ERR(t))
                return PTR_ERR(t);
 
-       sched_set_fifo(t);
-
        /*
         * We keep the reference to the task struct even if
         * the thread dies to avoid that the interrupt code
@@ -2715,7 +2721,7 @@ 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 f865e5f..dc7311d 100644 (file)
@@ -443,6 +443,10 @@ MODULE_PARM_DESC(noirqdebug, "Disable irq lockup detection when true");
 
 static int __init irqfixup_setup(char *str)
 {
+#ifdef CONFIG_PREEMPT_RT
+       pr_warn("irqfixup boot option not supported w/ CONFIG_PREEMPT_RT\n");
+       return 1;
+#endif
        irqfixup = 1;
        printk(KERN_WARNING "Misrouted IRQ fixup support enabled.\n");
        printk(KERN_WARNING "This may impact system performance.\n");
@@ -455,6 +459,10 @@ module_param(irqfixup, int, 0644);
 
 static int __init irqpoll_setup(char *str)
 {
+#ifdef CONFIG_PREEMPT_RT
+       pr_warn("irqpoll boot option not supported w/ CONFIG_PREEMPT_RT\n");
+       return 1;
+#endif
        irqfixup = 2;
        printk(KERN_WARNING "Misrouted IRQ fixup and polling support "
                                "enabled\n");
index eca8396..cbec10c 100644 (file)
 #include <linux/cpu.h>
 #include <linux/notifier.h>
 #include <linux/smp.h>
+#include <linux/smpboot.h>
+#include <linux/interrupt.h>
 #include <asm/processor.h>
 
 
 static DEFINE_PER_CPU(struct llist_head, raised_list);
 static DEFINE_PER_CPU(struct llist_head, lazy_list);
+static DEFINE_PER_CPU(struct task_struct *, irq_workd);
+
+static void wake_irq_workd(void)
+{
+       struct task_struct *tsk = __this_cpu_read(irq_workd);
+
+       if (!llist_empty(this_cpu_ptr(&lazy_list)) && tsk)
+               wake_up_process(tsk);
+}
+
+#ifdef CONFIG_SMP
+static void irq_work_wake(struct irq_work *entry)
+{
+       wake_irq_workd();
+}
+
+static DEFINE_PER_CPU(struct irq_work, irq_work_wakeup) =
+       IRQ_WORK_INIT_HARD(irq_work_wake);
+#endif
+
+static int irq_workd_should_run(unsigned int cpu)
+{
+       return !llist_empty(this_cpu_ptr(&lazy_list));
+}
 
 /*
  * Claim the entry so that no one else will poke at it.
@@ -52,15 +78,29 @@ void __weak arch_irq_work_raise(void)
 /* Enqueue on current CPU, work must already be claimed and preempt disabled */
 static void __irq_work_queue_local(struct irq_work *work)
 {
+       struct llist_head *list;
+       bool rt_lazy_work = false;
+       bool lazy_work = false;
+       int work_flags;
+
+       work_flags = atomic_read(&work->flags);
+       if (work_flags & IRQ_WORK_LAZY)
+               lazy_work = true;
+       else if (IS_ENABLED(CONFIG_PREEMPT_RT) &&
+                !(work_flags & IRQ_WORK_HARD_IRQ))
+               rt_lazy_work = true;
+
+       if (lazy_work || rt_lazy_work)
+               list = this_cpu_ptr(&lazy_list);
+       else
+               list = this_cpu_ptr(&raised_list);
+
+       if (!llist_add(&work->llnode, list))
+               return;
+
        /* If the work is "lazy", handle it from next tick if any */
-       if (atomic_read(&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)))
-                       arch_irq_work_raise();
-       }
+       if (!lazy_work || tick_nohz_tick_stopped())
+               arch_irq_work_raise();
 }
 
 /* Enqueue the irq work @work on the current CPU */
@@ -102,10 +142,28 @@ bool irq_work_queue_on(struct irq_work *work, int cpu)
        if (cpu != smp_processor_id()) {
                /* Arch remote IPI send/receive backend aren't NMI safe */
                WARN_ON_ONCE(in_nmi());
+
+               /*
+                * On PREEMPT_RT the items which are not marked as
+                * IRQ_WORK_HARD_IRQ are added to the lazy list and a HARD work
+                * item is used on the remote CPU to wake the thread.
+                */
+               if (IS_ENABLED(CONFIG_PREEMPT_RT) &&
+                   !(atomic_read(&work->flags) & IRQ_WORK_HARD_IRQ)) {
+
+                       if (!llist_add(&work->llnode, &per_cpu(lazy_list, cpu)))
+                               goto out;
+
+                       work = &per_cpu(irq_work_wakeup, cpu);
+                       if (!irq_work_claim(work))
+                               goto out;
+               }
+
                __smp_call_single_queue(cpu, &work->llnode);
        } else {
                __irq_work_queue_local(work);
        }
+out:
        preempt_enable();
 
        return true;
@@ -120,9 +178,8 @@ 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()));
@@ -153,6 +210,10 @@ void irq_work_single(void *arg)
         */
        flags &= ~IRQ_WORK_PENDING;
        (void)atomic_cmpxchg(&work->flags, flags, flags & ~IRQ_WORK_BUSY);
+
+       if ((IS_ENABLED(CONFIG_PREEMPT_RT) && !irq_work_is_hard(work)) ||
+           !arch_irq_work_has_interrupt())
+               rcuwait_wake_up(&work->irqwait);
 }
 
 static void irq_work_run_list(struct llist_head *list)
@@ -160,7 +221,12 @@ static void irq_work_run_list(struct llist_head *list)
        struct irq_work *work, *tmp;
        struct llist_node *llnode;
 
-       BUG_ON(!irqs_disabled());
+       /*
+        * On PREEMPT_RT IRQ-work which is not marked as HARD will be processed
+        * in a per-CPU thread in preemptible context. Only the items which are
+        * marked as IRQ_WORK_HARD_IRQ will be processed in hardirq context.
+        */
+       BUG_ON(!irqs_disabled() && !IS_ENABLED(CONFIG_PREEMPT_RT));
 
        if (llist_empty(list))
                return;
@@ -177,7 +243,10 @@ 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))
+               irq_work_run_list(this_cpu_ptr(&lazy_list));
+       else
+               wake_irq_workd();
 }
 EXPORT_SYMBOL_GPL(irq_work_run);
 
@@ -187,7 +256,11 @@ void irq_work_tick(void)
 
        if (!llist_empty(raised) && !arch_irq_work_has_interrupt())
                irq_work_run_list(raised);
-       irq_work_run_list(this_cpu_ptr(&lazy_list));
+
+       if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+               irq_work_run_list(this_cpu_ptr(&lazy_list));
+       else
+               wake_irq_workd();
 }
 
 /*
@@ -197,8 +270,42 @@ void irq_work_tick(void)
 void irq_work_sync(struct irq_work *work)
 {
        lockdep_assert_irqs_enabled();
+       might_sleep();
+
+       if ((IS_ENABLED(CONFIG_PREEMPT_RT) && !irq_work_is_hard(work)) ||
+           !arch_irq_work_has_interrupt()) {
+               rcuwait_wait_event(&work->irqwait, !irq_work_is_busy(work),
+                                  TASK_UNINTERRUPTIBLE);
+               return;
+       }
 
        while (atomic_read(&work->flags) & IRQ_WORK_BUSY)
                cpu_relax();
 }
 EXPORT_SYMBOL_GPL(irq_work_sync);
+
+static void run_irq_workd(unsigned int cpu)
+{
+       irq_work_run_list(this_cpu_ptr(&lazy_list));
+}
+
+static void irq_workd_setup(unsigned int cpu)
+{
+       sched_set_fifo_low(current);
+}
+
+static struct smp_hotplug_thread irqwork_threads = {
+       .store                  = &irq_workd,
+       .setup                  = irq_workd_setup,
+       .thread_should_run      = irq_workd_should_run,
+       .thread_fn              = run_irq_workd,
+       .thread_comm            = "irq_work/%u",
+};
+
+static __init int irq_work_init_threads(void)
+{
+       if (IS_ENABLED(CONFIG_PREEMPT_RT))
+               BUG_ON(smpboot_register_percpu_thread(&irqwork_threads));
+       return 0;
+}
+early_initcall(irq_work_init_threads);
index c589c7a..fb0ca1a 100644 (file)
@@ -978,7 +978,6 @@ void crash_kexec(struct pt_regs *regs)
        old_cpu = atomic_cmpxchg(&panic_cpu, PANIC_CPU_INVALID, this_cpu);
        if (old_cpu == PANIC_CPU_INVALID) {
                /* This is the 1st CPU which comes here, so go ahead. */
-               printk_safe_flush_on_panic();
                __crash_kexec(regs);
 
                /*
index 35859da..dfff31e 100644 (file)
@@ -138,6 +138,15 @@ KERNEL_ATTR_RO(vmcoreinfo);
 
 #endif /* CONFIG_CRASH_CORE */
 
+#if defined(CONFIG_PREEMPT_RT)
+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)
@@ -229,6 +238,9 @@ static struct attribute * kernel_attrs[] = {
        &rcu_expedited_attr.attr,
        &rcu_normal_attr.attr,
 #endif
+#ifdef CONFIG_PREEMPT_RT
+       &realtime_attr.attr,
+#endif
        NULL
 };
 
index 508fe52..3ce6a31 100644 (file)
@@ -264,6 +264,7 @@ EXPORT_SYMBOL_GPL(kthread_parkme);
 
 static int kthread(void *_create)
 {
+       static const struct sched_param param = { .sched_priority = 0 };
        /* Copy data: it's on kthread's stack */
        struct kthread_create_info *create = _create;
        int (*threadfn)(void *data) = create->threadfn;
@@ -294,6 +295,13 @@ static int kthread(void *_create)
        init_completion(&self->parked);
        current->vfork_done = &self->exited;
 
+       /*
+        * The new thread inherited kthreadd's priority and CPU mask. Reset
+        * back to default in case they have been changed.
+        */
+       sched_setscheduler_nocheck(current, SCHED_NORMAL, &param);
+       set_cpus_allowed_ptr(current, housekeeping_cpumask(HK_FLAG_KTHREAD));
+
        /* OK, tell user we're spawned, wait for stop or wakeup */
        __set_current_state(TASK_UNINTERRUPTIBLE);
        create->result = current;
@@ -391,7 +399,6 @@ struct task_struct *__kthread_create_on_node(int (*threadfn)(void *data),
        }
        task = create->result;
        if (!IS_ERR(task)) {
-               static const struct sched_param param = { .sched_priority = 0 };
                char name[TASK_COMM_LEN];
 
                /*
@@ -400,13 +407,6 @@ struct task_struct *__kthread_create_on_node(int (*threadfn)(void *data),
                 */
                vsnprintf(name, sizeof(name), namefmt, args);
                set_task_comm(task, name);
-               /*
-                * root may have changed our (kthreadd's) priority or CPU mask.
-                * The kernel thread should not inherit these properties.
-                */
-               sched_setscheduler_nocheck(task, SCHED_NORMAL, &param);
-               set_cpus_allowed_ptr(task,
-                                    housekeeping_cpumask(HK_FLAG_KTHREAD));
        }
        kfree(create);
        return task;
index 6d11cfb..c7fbf73 100644 (file)
@@ -3,7 +3,7 @@
 # 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 rwsem.o percpu-rwsem.o
 
 # Avoid recursion lockdep -> KCSAN -> ... -> lockdep.
 KCSAN_SANITIZE_lockdep.o := n
@@ -15,19 +15,23 @@ CFLAGS_REMOVE_mutex-debug.o = $(CC_FLAGS_FTRACE)
 CFLAGS_REMOVE_rtmutex-debug.o = $(CC_FLAGS_FTRACE)
 endif
 
-obj-$(CONFIG_DEBUG_MUTEXES) += mutex-debug.o
 obj-$(CONFIG_LOCKDEP) += lockdep.o
 ifeq ($(CONFIG_PROC_FS),y)
 obj-$(CONFIG_LOCKDEP) += lockdep_proc.o
 endif
 obj-$(CONFIG_SMP) += spinlock.o
-obj-$(CONFIG_LOCK_SPIN_ON_OWNER) += osq_lock.o
 obj-$(CONFIG_PROVE_LOCKING) += spinlock.o
 obj-$(CONFIG_QUEUED_SPINLOCKS) += qspinlock.o
 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 ($(CONFIG_PREEMPT_RT),y)
+obj-y += mutex.o
+obj-$(CONFIG_LOCK_SPIN_ON_OWNER) += osq_lock.o
+obj-$(CONFIG_DEBUG_MUTEXES) += mutex-debug.o
+endif
+obj-$(CONFIG_PREEMPT_RT) += mutex-rt.o rwsem-rt.o rwlock-rt.o
 obj-$(CONFIG_QUEUED_RWLOCKS) += qrwlock.o
 obj-$(CONFIG_LOCK_TORTURE_TEST) += locktorture.o
 obj-$(CONFIG_WW_MUTEX_SELFTEST) += test-ww_mutex.o
index 1f6a2f1..cfd0164 100644 (file)
@@ -5410,6 +5410,7 @@ static noinstr void check_flags(unsigned long flags)
                }
        }
 
+#ifndef CONFIG_PREEMPT_RT
        /*
         * We dont accurately track softirq state in e.g.
         * hardirq contexts (such as on 4KSTACKS), so only
@@ -5424,6 +5425,7 @@ static noinstr void check_flags(unsigned long flags)
                        DEBUG_LOCKS_WARN_ON(!current->softirqs_enabled);
                }
        }
+#endif
 
        if (!debug_locks)
                print_irqtrace_events(current);
diff --git a/kernel/locking/mutex-rt.c b/kernel/locking/mutex-rt.c
new file mode 100644 (file)
index 0000000..2b849e6
--- /dev/null
@@ -0,0 +1,224 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * 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 <linux/blkdev.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);
+
+static int _mutex_lock_blk_flush(struct mutex *lock, int state)
+{
+       /*
+        * Flush blk before ->pi_blocked_on is set. At schedule() time it is too
+        * late if one of the callbacks needs to acquire a sleeping lock.
+        */
+       if (blk_needs_flush_plug(current))
+               blk_schedule_flush_plug(current);
+       return __rt_mutex_lock_state(&lock->lock, state);
+}
+
+void __lockfunc _mutex_lock(struct mutex *lock)
+{
+       mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+       _mutex_lock_blk_flush(lock, TASK_UNINTERRUPTIBLE);
+}
+EXPORT_SYMBOL(_mutex_lock);
+
+void __lockfunc _mutex_lock_io_nested(struct mutex *lock, int subclass)
+{
+       int token;
+
+       token = io_schedule_prepare();
+
+       mutex_acquire_nest(&lock->dep_map, subclass, 0, NULL, _RET_IP_);
+       __rt_mutex_lock_state(&lock->lock, TASK_UNINTERRUPTIBLE);
+
+       io_schedule_finish(token);
+}
+EXPORT_SYMBOL_GPL(_mutex_lock_io_nested);
+
+int __lockfunc _mutex_lock_interruptible(struct mutex *lock)
+{
+       int ret;
+
+       mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+       ret = _mutex_lock_blk_flush(lock, TASK_INTERRUPTIBLE);
+       if (ret)
+               mutex_release(&lock->dep_map, _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 = _mutex_lock_blk_flush(lock, TASK_KILLABLE);
+       if (ret)
+               mutex_release(&lock->dep_map, _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_);
+       _mutex_lock_blk_flush(lock, TASK_UNINTERRUPTIBLE);
+}
+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_);
+       _mutex_lock_blk_flush(lock, TASK_UNINTERRUPTIBLE);
+}
+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 = _mutex_lock_blk_flush(lock, TASK_INTERRUPTIBLE);
+       if (ret)
+               mutex_release(&lock->dep_map, _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 = _mutex_lock_blk_flush(lock, TASK_KILLABLE);
+       if (ret)
+               mutex_release(&lock->dep_map, _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, _RET_IP_);
+       __rt_mutex_unlock(&lock->lock);
+}
+EXPORT_SYMBOL(_mutex_unlock);
+
+/**
+ * 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 36e6910..fb15010 100644 (file)
 
 #include "rtmutex_common.h"
 
-static void printk_task(struct task_struct *p)
-{
-       if (p)
-               printk("%16s:%5d [%p, %3d]", p->comm, task_pid_nr(p), p, p->prio);
-       else
-               printk("<none>");
-}
-
-static void printk_lock(struct rt_mutex *lock, int print_owner)
-{
-       if (lock->name)
-               printk(" [%p] {%s}\n",
-                       lock, lock->name);
-       else
-               printk(" [%p] {%s:%d}\n",
-                       lock, lock->file, lock->line);
-
-       if (print_owner && rt_mutex_owner(lock)) {
-               printk(".. ->owner: %p\n", lock->owner);
-               printk(".. held by:  ");
-               printk_task(rt_mutex_owner(lock));
-               printk("\n");
-       }
-}
-
 void rt_mutex_debug_task_free(struct task_struct *task)
 {
        DEBUG_LOCKS_WARN_ON(!RB_EMPTY_ROOT(&task->pi_waiters.rb_root));
        DEBUG_LOCKS_WARN_ON(task->pi_blocked_on);
 }
 
-/*
- * We fill out the fields in the waiter to store the information about
- * the deadlock. We print when we return. act_waiter can be NULL in
- * case of a remove waiter operation.
- */
-void debug_rt_mutex_deadlock(enum rtmutex_chainwalk chwalk,
-                            struct rt_mutex_waiter *act_waiter,
-                            struct rt_mutex *lock)
-{
-       struct task_struct *task;
-
-       if (!debug_locks || chwalk == RT_MUTEX_FULL_CHAINWALK || !act_waiter)
-               return;
-
-       task = rt_mutex_owner(act_waiter->lock);
-       if (task && task != current) {
-               act_waiter->deadlock_task_pid = get_pid(task_pid(task));
-               act_waiter->deadlock_lock = lock;
-       }
-}
-
-void debug_rt_mutex_print_deadlock(struct rt_mutex_waiter *waiter)
-{
-       struct task_struct *task;
-
-       if (!waiter->deadlock_lock || !debug_locks)
-               return;
-
-       rcu_read_lock();
-       task = pid_task(waiter->deadlock_task_pid, PIDTYPE_PID);
-       if (!task) {
-               rcu_read_unlock();
-               return;
-       }
-
-       if (!debug_locks_off()) {
-               rcu_read_unlock();
-               return;
-       }
-
-       pr_warn("\n");
-       pr_warn("============================================\n");
-       pr_warn("WARNING: circular locking deadlock detected!\n");
-       pr_warn("%s\n", print_tainted());
-       pr_warn("--------------------------------------------\n");
-       printk("%s/%d is deadlocking current task %s/%d\n\n",
-              task->comm, task_pid_nr(task),
-              current->comm, task_pid_nr(current));
-
-       printk("\n1) %s/%d is trying to acquire this lock:\n",
-              current->comm, task_pid_nr(current));
-       printk_lock(waiter->lock, 1);
-
-       printk("\n2) %s/%d is blocked on this lock:\n",
-               task->comm, task_pid_nr(task));
-       printk_lock(waiter->deadlock_lock, 1);
-
-       debug_show_held_locks(current);
-       debug_show_held_locks(task);
-
-       printk("\n%s/%d's [blocked] stackdump:\n\n",
-               task->comm, task_pid_nr(task));
-       show_stack(task, NULL, KERN_DEFAULT);
-       printk("\n%s/%d's [current] stackdump:\n\n",
-               current->comm, task_pid_nr(current));
-       dump_stack();
-       debug_show_all_locks();
-       rcu_read_unlock();
-
-       printk("[ turning off deadlock detection."
-              "Please report this trace. ]\n\n");
-}
-
 void debug_rt_mutex_lock(struct rt_mutex *lock)
 {
 }
@@ -158,12 +60,10 @@ void debug_rt_mutex_proxy_unlock(struct rt_mutex *lock)
 void debug_rt_mutex_init_waiter(struct rt_mutex_waiter *waiter)
 {
        memset(waiter, 0x11, sizeof(*waiter));
-       waiter->deadlock_task_pid = NULL;
 }
 
 void debug_rt_mutex_free_waiter(struct rt_mutex_waiter *waiter)
 {
-       put_pid(waiter->deadlock_task_pid);
        memset(waiter, 0x22, sizeof(*waiter));
 }
 
@@ -173,10 +73,8 @@ void debug_rt_mutex_init(struct rt_mutex *lock, const char *name, struct lock_cl
         * Make sure we are not reinitializing a held lock:
         */
        debug_check_no_locks_freed((void *)lock, sizeof(*lock));
-       lock->name = name;
 
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
        lockdep_init_map(&lock->dep_map, name, key, 0);
 #endif
 }
-
index fc54971..659e93e 100644 (file)
@@ -18,20 +18,9 @@ extern void debug_rt_mutex_unlock(struct rt_mutex *lock);
 extern void debug_rt_mutex_proxy_lock(struct rt_mutex *lock,
                                      struct task_struct *powner);
 extern void debug_rt_mutex_proxy_unlock(struct rt_mutex *lock);
-extern void debug_rt_mutex_deadlock(enum rtmutex_chainwalk chwalk,
-                                   struct rt_mutex_waiter *waiter,
-                                   struct rt_mutex *lock);
-extern void debug_rt_mutex_print_deadlock(struct rt_mutex_waiter *waiter);
-# define debug_rt_mutex_reset_waiter(w)                        \
-       do { (w)->deadlock_lock = NULL; } while (0)
 
 static inline bool debug_rt_mutex_detect_deadlock(struct rt_mutex_waiter *waiter,
                                                  enum rtmutex_chainwalk walk)
 {
        return (waiter != NULL);
 }
-
-static inline void rt_mutex_print_deadlock(struct rt_mutex_waiter *w)
-{
-       debug_rt_mutex_print_deadlock(w);
-}
index f00dd92..31b374d 100644 (file)
@@ -8,6 +8,11 @@
  *  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.rst for details.
  */
@@ -19,6 +24,7 @@
 #include <linux/sched/wake_q.h>
 #include <linux/sched/debug.h>
 #include <linux/timer.h>
+#include <linux/ww_mutex.h>
 
 #include "rtmutex_common.h"
 
@@ -136,6 +142,12 @@ 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.
@@ -227,7 +239,7 @@ static inline bool unlock_rt_mutex_safe(struct rt_mutex *lock,
  * Only use with rt_mutex_waiter_{less,equal}()
  */
 #define task_to_waiter(p)      \
-       &(struct rt_mutex_waiter){ .prio = (p)->prio, .deadline = (p)->dl.deadline }
+       &(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,
@@ -267,6 +279,27 @@ rt_mutex_waiter_equal(struct rt_mutex_waiter *left,
        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)
 {
@@ -371,6 +404,14 @@ 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:
  */
@@ -378,7 +419,8 @@ 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;
 }
 
 /*
@@ -514,7 +556,7 @@ 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;
 
        /*
@@ -597,7 +639,6 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
         * walk, we detected a deadlock.
         */
        if (lock == orig_lock || rt_mutex_owner(lock) == top_task) {
-               debug_rt_mutex_deadlock(chwalk, orig_waiter, lock);
                raw_spin_unlock(&lock->wait_lock);
                ret = -EDEADLK;
                goto out_unlock_pi;
@@ -694,13 +735,16 @@ 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;
        }
@@ -801,9 +845,11 @@ 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);
 
@@ -839,12 +885,11 @@ 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.
@@ -862,14 +907,12 @@ 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 (!rt_mutex_waiter_less(task_to_waiter(task),
-                                                 rt_mutex_top_waiter(lock)))
+                       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
@@ -916,6 +959,329 @@ takeit:
        return 1;
 }
 
+#ifdef CONFIG_PREEMPT_RT
+/*
+ * preemptible spin_lock functions:
+ */
+static inline void rt_spin_lock_fastlock(struct rt_mutex *lock,
+                                        void  (*slowfn)(struct rt_mutex *lock))
+{
+       might_sleep_no_state_check();
+
+       if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current)))
+               return;
+       else
+               slowfn(lock);
+}
+
+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);
+/*
+ * 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.
+ */
+void __sched rt_spin_lock_slowlock_locked(struct rt_mutex *lock,
+                                         struct rt_mutex_waiter *waiter,
+                                         unsigned long flags)
+{
+       struct task_struct *lock_owner, *self = current;
+       struct rt_mutex_waiter *top_waiter;
+       int ret;
+
+       if (__try_to_take_rt_mutex(lock, self, NULL, STEAL_LATERAL))
+               return;
+
+       BUG_ON(rt_mutex_owner(lock) == self);
+
+       /*
+        * 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().
+        */
+       raw_spin_lock(&self->pi_lock);
+       self->saved_state = self->state;
+       __set_current_state_no_track(TASK_UNINTERRUPTIBLE);
+       raw_spin_unlock(&self->pi_lock);
+
+       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;
+
+               top_waiter = rt_mutex_top_waiter(lock);
+               lock_owner = rt_mutex_owner(lock);
+
+               raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
+
+               if (top_waiter != waiter || adaptive_wait(lock, lock_owner))
+                       preempt_schedule_lock();
+
+               raw_spin_lock_irqsave(&lock->wait_lock, flags);
+
+               raw_spin_lock(&self->pi_lock);
+               __set_current_state_no_track(TASK_UNINTERRUPTIBLE);
+               raw_spin_unlock(&self->pi_lock);
+       }
+
+       /*
+        * 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.
+        */
+       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);
+
+       /*
+        * try_to_take_rt_mutex() sets the waiter bit
+        * unconditionally. We might have to fix that up:
+        */
+       fixup_rt_mutex_waiters(lock);
+
+       BUG_ON(rt_mutex_has_waiters(lock) && waiter == rt_mutex_top_waiter(lock));
+       BUG_ON(!RB_EMPTY_NODE(&waiter->tree_entry));
+}
+
+static void noinline __sched rt_spin_lock_slowlock(struct rt_mutex *lock)
+{
+       struct rt_mutex_waiter waiter;
+       unsigned long flags;
+
+       rt_mutex_init_waiter(&waiter, true);
+
+       raw_spin_lock_irqsave(&lock->wait_lock, flags);
+       rt_spin_lock_slowlock_locked(lock, &waiter, flags);
+       raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
+       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);
+/*
+ * Slow path to release a rt_mutex spin_lock style
+ */
+void __sched rt_spin_lock_slowunlock(struct rt_mutex *lock)
+{
+       unsigned long flags;
+       DEFINE_WAKE_Q(wake_q);
+       DEFINE_WAKE_Q(wake_sleeper_q);
+       bool postunlock;
+
+       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);
+
+       if (postunlock)
+               rt_mutex_postunlock(&wake_q, &wake_sleeper_q);
+}
+
+void __lockfunc rt_spin_lock(spinlock_t *lock)
+{
+       spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+       rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock);
+       rcu_read_lock();
+       migrate_disable();
+}
+EXPORT_SYMBOL(rt_spin_lock);
+
+void __lockfunc __rt_spin_lock(struct rt_mutex *lock)
+{
+       rt_spin_lock_fastlock(lock, rt_spin_lock_slowlock);
+}
+
+#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);
+       rcu_read_lock();
+       migrate_disable();
+}
+EXPORT_SYMBOL(rt_spin_lock_nested);
+
+void __lockfunc rt_spin_lock_nest_lock(spinlock_t *lock,
+                                      struct lockdep_map *nest_lock)
+{
+       spin_acquire_nest(&lock->dep_map, 0, 0, nest_lock, _RET_IP_);
+       rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock);
+       rcu_read_lock();
+       migrate_disable();
+}
+EXPORT_SYMBOL(rt_spin_lock_nest_lock);
+#endif
+
+void __lockfunc rt_spin_unlock(spinlock_t *lock)
+{
+       /* NOTE: we always pass in '1' for nested, for simplicity */
+       spin_release(&lock->dep_map, _RET_IP_);
+       migrate_enable();
+       rcu_read_unlock();
+       rt_spin_lock_fastunlock(&lock->lock, rt_spin_lock_slowunlock);
+}
+EXPORT_SYMBOL(rt_spin_unlock);
+
+void __lockfunc __rt_spin_unlock(struct rt_mutex *lock)
+{
+       rt_spin_lock_fastunlock(lock, rt_spin_lock_slowunlock);
+}
+EXPORT_SYMBOL(__rt_spin_unlock);
+
+/*
+ * 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_lock_unlock(spinlock_t *lock)
+{
+       spin_lock(lock);
+       spin_unlock(lock);
+}
+EXPORT_SYMBOL(rt_spin_lock_unlock);
+
+int __lockfunc rt_spin_trylock(spinlock_t *lock)
+{
+       int ret;
+
+       ret = __rt_mutex_trylock(&lock->lock);
+       if (ret) {
+               spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
+               rcu_read_lock();
+               migrate_disable();
+       }
+       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) {
+               spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
+               rcu_read_lock();
+               migrate_disable();
+       } else {
+               local_bh_enable();
+       }
+       return ret;
+}
+EXPORT_SYMBOL(rt_spin_trylock_bh);
+
+void
+__rt_spin_lock_init(spinlock_t *lock, 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 *)lock, sizeof(*lock));
+       lockdep_init_map(&lock->dep_map, name, key, 0);
+#endif
+}
+EXPORT_SYMBOL(__rt_spin_lock_init);
+
+#endif /* PREEMPT_RT */
+
+#ifdef CONFIG_PREEMPT_RT
+       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 = READ_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.
  *
@@ -948,6 +1314,22 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
                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));
+
        waiter->task = task;
        waiter->lock = lock;
        waiter->prio = task->prio;
@@ -971,7 +1353,7 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
                rt_mutex_enqueue_pi(owner, waiter);
 
                rt_mutex_adjust_prio(owner);
-               if (owner->pi_blocked_on)
+               if (rt_mutex_real_waiter(owner->pi_blocked_on))
                        chain_walk = 1;
        } else if (rt_mutex_cond_detect_deadlock(waiter, chwalk)) {
                chain_walk = 1;
@@ -1013,6 +1395,7 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
  * 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;
@@ -1052,7 +1435,10 @@ static void mark_wakeup_next_waiter(struct wake_q_head *wake_q,
         * Pairs with preempt_enable() in rt_mutex_postunlock();
         */
        preempt_disable();
-       wake_q_add(wake_q, waiter->task);
+       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);
 }
 
@@ -1067,7 +1453,7 @@ static void remove_waiter(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;
+       struct rt_mutex *next_lock = NULL;
 
        lockdep_assert_held(&lock->wait_lock);
 
@@ -1093,7 +1479,8 @@ static void remove_waiter(struct rt_mutex *lock,
        rt_mutex_adjust_prio(owner);
 
        /* Store the lock on which owner is blocked or NULL */
-       next_lock = task_blocked_on_lock(owner);
+       if (rt_mutex_real_waiter(owner->pi_blocked_on))
+               next_lock = task_blocked_on_lock(owner);
 
        raw_spin_unlock(&owner->pi_lock);
 
@@ -1129,26 +1516,28 @@ void rt_mutex_adjust_pi(struct task_struct *task)
        raw_spin_lock_irqsave(&task->pi_lock, flags);
 
        waiter = task->pi_blocked_on;
-       if (!waiter || rt_mutex_waiter_equal(waiter, task_to_waiter(task))) {
+       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)
+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;
 }
 
 /**
@@ -1164,7 +1553,8 @@ void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter)
 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;
 
@@ -1173,24 +1563,23 @@ __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 (likely(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;
                }
 
                raw_spin_unlock_irq(&lock->wait_lock);
 
-               debug_rt_mutex_print_deadlock(waiter);
-
                schedule();
 
                raw_spin_lock_irq(&lock->wait_lock);
@@ -1211,43 +1600,110 @@ static void rt_mutex_handle_deadlock(int res, int detect_deadlock,
        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();
        }
 }
 
-/*
- * Slow path lock function:
- */
-static int __sched
-rt_mutex_slowlock(struct rt_mutex *lock, int state,
-                 struct hrtimer_sleeper *timeout,
-                 enum rtmutex_chainwalk chwalk)
+static __always_inline void ww_mutex_lock_acquired(struct ww_mutex *ww,
+                                                  struct ww_acquire_ctx *ww_ctx)
 {
-       struct rt_mutex_waiter waiter;
-       unsigned long flags;
-       int ret = 0;
+#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);
 
-       rt_mutex_init_waiter(&waiter);
+       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;
+       }
 
        /*
-        * Technically we could use raw_spin_[un]lock_irq() here, but this can
-        * be called in early boot if the cmpxchg() fast path is disabled
-        * (debug, no architecture support). In this case we will acquire the
-        * rtmutex with lock->wait_lock held. But we cannot unconditionally
-        * enable interrupts in that early boot case. So we need to use the
-        * irqsave/restore variants.
+        * Naughty, using a different class will lead to undefined behavior!
         */
-       raw_spin_lock_irqsave(&lock->wait_lock, flags);
+       DEBUG_LOCKS_WARN_ON(ww_ctx->ww_class != ww->ww_class);
+#endif
+       ww_ctx->acquired++;
+}
+
+#ifdef CONFIG_PREEMPT_RT
+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.rb_root,
+                                            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;
+
+#ifdef CONFIG_PREEMPT_RT
+       if (ww_ctx) {
+               struct ww_mutex *ww;
+
+               ww = container_of(lock, struct ww_mutex, base.lock);
+               if (unlikely(ww_ctx == READ_ONCE(ww->ctx)))
+                       return -EALREADY;
+       }
+#endif
 
        /* Try to acquire the lock again: */
        if (try_to_take_rt_mutex(lock, current, NULL)) {
-               raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
+               if (ww_ctx)
+                       ww_mutex_account_lock(lock, ww_ctx);
                return 0;
        }
 
@@ -1257,16 +1713,26 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state,
        if (unlikely(timeout))
                hrtimer_start_expires(&timeout->timer, HRTIMER_MODE_ABS);
 
-       ret = task_blocks_on_rt_mutex(lock, &waiter, current, chwalk);
+       ret = task_blocks_on_rt_mutex(lock, waiter, current, chwalk);
 
-       if (likely(!ret))
+       if (likely(!ret)) {
                /* sleep on the mutex */
-               ret = __rt_mutex_slowlock(lock, state, timeout, &waiter);
+               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);
+       }
 
        if (unlikely(ret)) {
                __set_current_state(TASK_RUNNING);
-               remove_waiter(lock, &waiter);
-               rt_mutex_handle_deadlock(ret, chwalk, &waiter);
+               remove_waiter(lock, waiter);
+               /* ww_mutex wants to report EDEADLK/EALREADY, let it */
+               if (!ww_ctx)
+                       rt_mutex_handle_deadlock(ret, chwalk, waiter);
+       } else if (ww_ctx) {
+               ww_mutex_account_lock(lock, ww_ctx);
        }
 
        /*
@@ -1274,6 +1740,36 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state,
         * unconditionally. We might have to fix that up.
         */
        fixup_rt_mutex_waiters(lock);
+       return ret;
+}
+
+/*
+ * Slow path lock function:
+ */
+static int __sched
+rt_mutex_slowlock(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;
+       unsigned long flags;
+       int ret = 0;
+
+       rt_mutex_init_waiter(&waiter, false);
+
+       /*
+        * Technically we could use raw_spin_[un]lock_irq() here, but this can
+        * be called in early boot if the cmpxchg() fast path is disabled
+        * (debug, no architecture support). In this case we will acquire the
+        * rtmutex with lock->wait_lock held. But we cannot unconditionally
+        * enable interrupts in that early boot case. So we need to use the
+        * irqsave/restore variants.
+        */
+       raw_spin_lock_irqsave(&lock->wait_lock, flags);
+
+       ret = rt_mutex_slowlock_locked(lock, state, timeout, chwalk, ww_ctx,
+                                      &waiter);
 
        raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
 
@@ -1334,7 +1830,8 @@ static inline int rt_mutex_slowtrylock(struct rt_mutex *lock)
  * 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;
 
@@ -1388,7 +1885,7 @@ 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);
 
        return true; /* call rt_mutex_postunlock() */
@@ -1402,29 +1899,16 @@ 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)))
                return 0;
 
-       return slowfn(lock, state, NULL, RT_MUTEX_MIN_CHAINWALK);
-}
-
-static inline int
-rt_mutex_timed_fastlock(struct rt_mutex *lock, int state,
-                       struct hrtimer_sleeper *timeout,
-                       enum rtmutex_chainwalk chwalk,
-                       int (*slowfn)(struct rt_mutex *lock, int state,
-                                     struct hrtimer_sleeper *timeout,
-                                     enum rtmutex_chainwalk chwalk))
-{
-       if (chwalk == RT_MUTEX_MIN_CHAINWALK &&
-           likely(rt_mutex_cmpxchg_acquire(lock, NULL, current)))
-               return 0;
-
-       return slowfn(lock, state, timeout, chwalk);
+       return slowfn(lock, state, NULL, RT_MUTEX_MIN_CHAINWALK, ww_ctx);
 }
 
 static inline int
@@ -1440,9 +1924,11 @@ rt_mutex_fasttrylock(struct rt_mutex *lock,
 /*
  * Performs the wakeup of the top-waiter and re-enables preemption.
  */
-void rt_mutex_postunlock(struct wake_q_head *wake_q)
+void rt_mutex_postunlock(struct wake_q_head *wake_q,
+                        struct wake_q_head *wake_sleeper_q)
 {
        wake_up_q(wake_q);
+       wake_up_q_sleeper(wake_sleeper_q);
 
        /* Pairs with preempt_disable() in rt_mutex_slowunlock() */
        preempt_enable();
@@ -1451,23 +1937,46 @@ void rt_mutex_postunlock(struct wake_q_head *wake_q)
 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))
 {
        DEFINE_WAKE_Q(wake_q);
+       DEFINE_WAKE_Q(wake_sleeper_q);
 
        if (likely(rt_mutex_cmpxchg_release(lock, current, NULL)))
                return;
 
-       if (slowfn(lock, &wake_q))
-               rt_mutex_postunlock(&wake_q);
+       if (slowfn(lock, &wake_q, &wake_sleeper_q))
+               rt_mutex_postunlock(&wake_q, &wake_sleeper_q);
 }
 
-static inline void __rt_mutex_lock(struct rt_mutex *lock, unsigned int subclass)
+int __sched __rt_mutex_lock_state(struct rt_mutex *lock, int state)
 {
        might_sleep();
+       return rt_mutex_fastlock(lock, state, NULL, rt_mutex_slowlock);
+}
+
+/**
+ * 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
+ */
+static inline int __sched rt_mutex_lock_state(struct rt_mutex *lock,
+                                             unsigned int subclass, int state)
+{
+       int ret;
 
        mutex_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
-       rt_mutex_fastlock(lock, TASK_UNINTERRUPTIBLE, rt_mutex_slowlock);
+       ret = __rt_mutex_lock_state(lock, state);
+       if (ret)
+               mutex_release(&lock->dep_map, _RET_IP_);
+       return ret;
+}
+
+static inline void __rt_mutex_lock(struct rt_mutex *lock, unsigned int subclass)
+{
+       rt_mutex_lock_state(lock, subclass, TASK_UNINTERRUPTIBLE);
 }
 
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
@@ -1508,16 +2017,7 @@ EXPORT_SYMBOL_GPL(rt_mutex_lock);
  */
 int __sched rt_mutex_lock_interruptible(struct rt_mutex *lock)
 {
-       int ret;
-
-       might_sleep();
-
-       mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
-       ret = rt_mutex_fastlock(lock, TASK_INTERRUPTIBLE, rt_mutex_slowlock);
-       if (ret)
-               mutex_release(&lock->dep_map, _RET_IP_);
-
-       return ret;
+       return rt_mutex_lock_state(lock, 0, TASK_INTERRUPTIBLE);
 }
 EXPORT_SYMBOL_GPL(rt_mutex_lock_interruptible);
 
@@ -1534,36 +2034,17 @@ int __sched __rt_mutex_futex_trylock(struct rt_mutex *lock)
        return __rt_mutex_slowtrylock(lock);
 }
 
-/**
- * rt_mutex_timed_lock - lock a rt_mutex interruptible
- *                     the timeout structure is provided
- *                     by the caller
- *
- * @lock:              the rt_mutex to be locked
- * @timeout:           timeout structure or NULL (no timeout)
- *
- * Returns:
- *  0          on success
- * -EINTR      when interrupted by a signal
- * -ETIMEDOUT  when the timeout expired
- */
-int
-rt_mutex_timed_lock(struct rt_mutex *lock, struct hrtimer_sleeper *timeout)
+int __sched __rt_mutex_trylock(struct rt_mutex *lock)
 {
-       int ret;
-
-       might_sleep();
-
-       mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
-       ret = rt_mutex_timed_fastlock(lock, TASK_INTERRUPTIBLE, timeout,
-                                      RT_MUTEX_MIN_CHAINWALK,
-                                      rt_mutex_slowlock);
-       if (ret)
-               mutex_release(&lock->dep_map, _RET_IP_);
+#ifdef CONFIG_PREEMPT_RT
+       if (WARN_ON_ONCE(in_irq() || in_nmi()))
+#else
+       if (WARN_ON_ONCE(in_irq() || in_nmi() || in_serving_softirq()))
+#endif
+               return 0;
 
-       return ret;
+       return rt_mutex_fasttrylock(lock, rt_mutex_slowtrylock);
 }
-EXPORT_SYMBOL_GPL(rt_mutex_timed_lock);
 
 /**
  * rt_mutex_trylock - try to lock a rt_mutex
@@ -1580,10 +2061,7 @@ int __sched rt_mutex_trylock(struct rt_mutex *lock)
 {
        int ret;
 
-       if (WARN_ON_ONCE(in_irq() || in_nmi() || in_serving_softirq()))
-               return 0;
-
-       ret = rt_mutex_fasttrylock(lock, rt_mutex_slowtrylock);
+       ret = __rt_mutex_trylock(lock);
        if (ret)
                mutex_acquire(&lock->dep_map, 0, 1, _RET_IP_);
 
@@ -1591,6 +2069,11 @@ int __sched rt_mutex_trylock(struct rt_mutex *lock)
 }
 EXPORT_SYMBOL_GPL(rt_mutex_trylock);
 
+void __sched __rt_mutex_unlock(struct rt_mutex *lock)
+{
+       rt_mutex_fastunlock(lock, rt_mutex_slowunlock);
+}
+
 /**
  * rt_mutex_unlock - unlock a rt_mutex
  *
@@ -1599,16 +2082,13 @@ EXPORT_SYMBOL_GPL(rt_mutex_trylock);
 void __sched rt_mutex_unlock(struct rt_mutex *lock)
 {
        mutex_release(&lock->dep_map, _RET_IP_);
-       rt_mutex_fastunlock(lock, rt_mutex_slowunlock);
+       __rt_mutex_unlock(lock);
 }
 EXPORT_SYMBOL_GPL(rt_mutex_unlock);
 
-/**
- * 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 *wake_q)
+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);
 
@@ -1625,23 +2105,35 @@ bool __sched __rt_mutex_futex_unlock(struct rt_mutex *lock,
         * avoid inversion prior to the wakeup.  preempt_disable()
         * therein pairs with rt_mutex_postunlock().
         */
-       mark_wakeup_next_waiter(wake_q, lock);
+       mark_wakeup_next_waiter(wake_q, wq_sleeper, lock);
 
        return true; /* call postunlock() */
 }
 
+/**
+ * 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 *wake_q,
+                                    struct wake_q_head *wq_sleeper)
+{
+       return __rt_mutex_unlock_common(lock, wake_q, wq_sleeper);
+}
+
 void __sched rt_mutex_futex_unlock(struct rt_mutex *lock)
 {
        DEFINE_WAKE_Q(wake_q);
+       DEFINE_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);
+       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);
+               rt_mutex_postunlock(&wake_q, &wake_sleeper_q);
 }
 
 /**
@@ -1655,9 +2147,6 @@ void __sched rt_mutex_futex_unlock(struct rt_mutex *lock)
 void rt_mutex_destroy(struct rt_mutex *lock)
 {
        WARN_ON(rt_mutex_is_locked(lock));
-#ifdef CONFIG_DEBUG_RT_MUTEXES
-       lock->magic = NULL;
-#endif
 }
 EXPORT_SYMBOL_GPL(rt_mutex_destroy);
 
@@ -1680,7 +2169,7 @@ void __rt_mutex_init(struct rt_mutex *lock, const char *name,
        if (name && key)
                debug_rt_mutex_init(lock, name, key);
 }
-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
@@ -1700,6 +2189,14 @@ void rt_mutex_init_proxy_locked(struct rt_mutex *lock,
                                struct task_struct *proxy_owner)
 {
        __rt_mutex_init(lock, NULL, NULL);
+#ifdef CONFIG_DEBUG_SPINLOCK
+       /*
+        * get another key class for the wait_lock. LOCK_PI and UNLOCK_PI is
+        * holding the ->wait_lock of the proxy_lock while unlocking a sleeping
+        * lock.
+        */
+       raw_spin_lock_init(&lock->wait_lock);
+#endif
        debug_rt_mutex_proxy_lock(lock, proxy_owner);
        rt_mutex_set_owner(lock, proxy_owner);
 }
@@ -1722,6 +2219,26 @@ void rt_mutex_proxy_unlock(struct rt_mutex *lock)
        rt_mutex_set_owner(lock, NULL);
 }
 
+static void fixup_rt_mutex_blocked(struct rt_mutex *lock)
+{
+       struct task_struct *tsk = current;
+       /*
+        * 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.
+        */
+       raw_spin_lock(&tsk->pi_lock);
+       tsk->pi_blocked_on = NULL;
+       raw_spin_unlock(&tsk->pi_lock);
+}
+
 /**
  * __rt_mutex_start_proxy_lock() - Start lock acquisition for another task
  * @lock:              the rt_mutex to take
@@ -1752,6 +2269,34 @@ int __rt_mutex_start_proxy_lock(struct rt_mutex *lock,
        if (try_to_take_rt_mutex(lock, task, NULL))
                return 1;
 
+#ifdef CONFIG_PREEMPT_RT
+       /*
+        * 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,
                                      RT_MUTEX_FULL_CHAINWALK);
@@ -1766,7 +2311,8 @@ int __rt_mutex_start_proxy_lock(struct rt_mutex *lock,
                ret = 0;
        }
 
-       debug_rt_mutex_print_deadlock(waiter);
+       if (ret)
+               fixup_rt_mutex_blocked(lock);
 
        return ret;
 }
@@ -1851,12 +2397,15 @@ int rt_mutex_wait_proxy_lock(struct rt_mutex *lock,
        raw_spin_lock_irq(&lock->wait_lock);
        /* sleep on the mutex */
        set_current_state(TASK_INTERRUPTIBLE);
-       ret = __rt_mutex_slowlock(lock, TASK_INTERRUPTIBLE, to, waiter);
+       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);
+       if (ret)
+               fixup_rt_mutex_blocked(lock);
+
        raw_spin_unlock_irq(&lock->wait_lock);
 
        return ret;
@@ -1918,3 +2467,97 @@ bool rt_mutex_cleanup_proxy_lock(struct rt_mutex *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 int 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
+int __sched
+ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
+{
+       int ret;
+
+       might_sleep();
+
+       mutex_acquire_nest(&lock->base.dep_map, 0, 0,
+                          ctx ? &ctx->dep_map : NULL, _RET_IP_);
+       ret = rt_mutex_slowlock(&lock->base.lock, TASK_INTERRUPTIBLE, NULL, 0,
+                               ctx);
+       if (ret)
+               mutex_release(&lock->base.dep_map, _RET_IP_);
+       else if (!ret && ctx && ctx->acquired > 1)
+               return ww_mutex_deadlock_injection(lock, ctx);
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(ww_mutex_lock_interruptible);
+
+int __sched
+ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
+{
+       int ret;
+
+       might_sleep();
+
+       mutex_acquire_nest(&lock->base.dep_map, 0, 0,
+                          ctx ? &ctx->dep_map : NULL, _RET_IP_);
+       ret = rt_mutex_slowlock(&lock->base.lock, TASK_UNINTERRUPTIBLE, NULL, 0,
+                               ctx);
+       if (ret)
+               mutex_release(&lock->base.dep_map, _RET_IP_);
+       else if (!ret && ctx && ctx->acquired > 1)
+               return ww_mutex_deadlock_injection(lock, ctx);
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(ww_mutex_lock);
+
+void __sched ww_mutex_unlock(struct ww_mutex *lock)
+{
+       /*
+        * The unlocking fastpath is the 0->1 transition from 'locked'
+        * into 'unlocked' state:
+        */
+       if (lock->ctx) {
+#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, _RET_IP_);
+       __rt_mutex_unlock(&lock->base.lock);
+}
+EXPORT_SYMBOL(ww_mutex_unlock);
+
+int __rt_mutex_owner_current(struct rt_mutex *lock)
+{
+       return rt_mutex_owner(lock) == current;
+}
+EXPORT_SYMBOL(__rt_mutex_owner_current);
+#endif
index 732f96a..338ccd2 100644 (file)
 #define debug_rt_mutex_proxy_unlock(l)                 do { } while (0)
 #define debug_rt_mutex_unlock(l)                       do { } while (0)
 #define debug_rt_mutex_init(m, n, k)                   do { } while (0)
-#define debug_rt_mutex_deadlock(d, a ,l)               do { } while (0)
-#define debug_rt_mutex_print_deadlock(w)               do { } while (0)
 #define debug_rt_mutex_reset_waiter(w)                 do { } while (0)
 
-static inline void rt_mutex_print_deadlock(struct rt_mutex_waiter *w)
-{
-       WARN(1, "rtmutex deadlock detected\n");
-}
-
 static inline bool debug_rt_mutex_detect_deadlock(struct rt_mutex_waiter *w,
                                                  enum rtmutex_chainwalk walk)
 {
index ca6fb48..248a7d9 100644 (file)
@@ -15,6 +15,7 @@
 
 #include <linux/rtmutex.h>
 #include <linux/sched/wake_q.h>
+#include <linux/sched/debug.h>
 
 /*
  * This is the control structure for tasks blocked on a rt_mutex,
@@ -29,12 +30,8 @@ struct rt_mutex_waiter {
        struct rb_node          pi_tree_entry;
        struct task_struct      *task;
        struct rt_mutex         *lock;
-#ifdef CONFIG_DEBUG_RT_MUTEXES
-       unsigned long           ip;
-       struct pid              *deadlock_task_pid;
-       struct rt_mutex         *deadlock_lock;
-#endif
        int prio;
+       bool                    savestate;
        u64 deadline;
 };
 
@@ -130,11 +127,14 @@ 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);
-extern void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter);
+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);
@@ -152,9 +152,27 @@ 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);
-
-extern void rt_mutex_postunlock(struct wake_q_head *wake_q);
+                                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 *wake_sleeper_q);
+
+/* RW semaphore special interface */
+struct ww_acquire_ctx;
+
+extern int __rt_mutex_lock_state(struct rt_mutex *lock, int state);
+extern int __rt_mutex_trylock(struct rt_mutex *lock);
+extern void __rt_mutex_unlock(struct rt_mutex *lock);
+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);
+void __sched rt_spin_lock_slowlock_locked(struct rt_mutex *lock,
+                                         struct rt_mutex_waiter *waiter,
+                                         unsigned long flags);
+void __sched rt_spin_lock_slowunlock(struct rt_mutex *lock);
 
 #ifdef CONFIG_DEBUG_RT_MUTEXES
 # include "rtmutex-debug.h"
diff --git a/kernel/locking/rwlock-rt.c b/kernel/locking/rwlock-rt.c
new file mode 100644 (file)
index 0000000..3d2d1f1
--- /dev/null
@@ -0,0 +1,334 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/sched/debug.h>
+#include <linux/export.h>
+
+#include "rtmutex_common.h"
+#include <linux/rwlock_types_rt.h>
+
+/*
+ * RT-specific reader/writer locks
+ *
+ * write_lock()
+ *  1) Lock lock->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
+ *
+ * write_unlock()
+ *  1) Remove the write locked marker
+ *  2) Set the reader BIAS so readers can use the fast path again
+ *  3) Unlock lock->rtmutex to release blocked readers
+ *
+ * read_lock()
+ *  1) Try fast path acquisition (reader BIAS is set)
+ *  2) Take lock->rtmutex.wait_lock which protects the writelocked flag
+ *  3) If !writelocked, acquire it for read
+ *  4) If writelocked, block on lock->rtmutex
+ *  5) unlock lock->rtmutex, goto 1)
+ *
+ * read_unlock()
+ *  1) Try fast path release (reader count != 1)
+ *  2) Wake the writer waiting in write_lock()#3
+ *
+ * read_lock()#3 has the consequence, that rw locks on RT are not writer
+ * fair, but writers, which should be avoided in RT tasks (think tasklist
+ * lock), are subject to the rtmutex priority/DL inheritance mechanism.
+ *
+ * It's possible to make the rw locks 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 __rwlock_biased_rt_init(struct rt_rw_lock *lock, 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 *)lock, sizeof(*lock));
+       lockdep_init_map(&lock->dep_map, name, key, 0);
+#endif
+       atomic_set(&lock->readers, READER_BIAS);
+       rt_mutex_init(&lock->rtmutex);
+       lock->rtmutex.save_state = 1;
+}
+
+static int __read_rt_trylock(struct rt_rw_lock *lock)
+{
+       int r, old;
+
+       /*
+        * Increment reader count, if lock->readers < 0, i.e. READER_BIAS is
+        * set.
+        */
+       for (r = atomic_read(&lock->readers); r < 0;) {
+               old = atomic_cmpxchg(&lock->readers, r, r + 1);
+               if (likely(old == r))
+                       return 1;
+               r = old;
+       }
+       return 0;
+}
+
+static void __read_rt_lock(struct rt_rw_lock *lock)
+{
+       struct rt_mutex *m = &lock->rtmutex;
+       struct rt_mutex_waiter waiter;
+       unsigned long flags;
+
+       if (__read_rt_trylock(lock))
+               return;
+
+       raw_spin_lock_irqsave(&m->wait_lock, flags);
+       /*
+        * Allow readers as long as the writer has not completely
+        * acquired the semaphore for write.
+        */
+       if (atomic_read(&lock->readers) != WRITER_BIAS) {
+               atomic_inc(&lock->readers);
+               raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+               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
+        *                      read_lock()
+        *                                      write_lock()
+        *                                      rtmutex_lock(m)
+        *                                      swait()
+        * read_lock()
+        * unlock(m->wait_lock)
+        *                      read_unlock()
+        *                      swake()
+        *                                      lock(m->wait_lock)
+        *                                      lock->writelocked=true
+        *                                      unlock(m->wait_lock)
+        *
+        *                                      write_unlock()
+        *                                      lock->writelocked=false
+        *                                      rtmutex_unlock(m)
+        *                      read_lock()
+        *                                      write_lock()
+        *                                      rtmutex_lock(m)
+        *                                      swait()
+        * rtmutex_lock(m)
+        *
+        * That would put Reader1 behind the writer waiting on
+        * Reader2 to call read_unlock() which might be unbound.
+        */
+       rt_mutex_init_waiter(&waiter, true);
+       rt_spin_lock_slowlock_locked(m, &waiter, flags);
+       /*
+        * 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(&lock->readers);
+       raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+       rt_spin_lock_slowunlock(m);
+
+       debug_rt_mutex_free_waiter(&waiter);
+}
+
+static void __read_rt_unlock(struct rt_rw_lock *lock)
+{
+       struct rt_mutex *m = &lock->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(&lock->readers))
+               return;
+
+       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, but to clean up the rw
+        * lock 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 __write_unlock_common(struct rt_rw_lock *lock, int bias,
+                                 unsigned long flags)
+{
+       struct rt_mutex *m = &lock->rtmutex;
+
+       atomic_add(READER_BIAS - bias, &lock->readers);
+       raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+       rt_spin_lock_slowunlock(m);
+}
+
+static void __write_rt_lock(struct rt_rw_lock *lock)
+{
+       struct rt_mutex *m = &lock->rtmutex;
+       struct task_struct *self = current;
+       unsigned long flags;
+
+       /* Take the rtmutex as a first step */
+       __rt_spin_lock(m);
+
+       /* Force readers into slow path */
+       atomic_sub(READER_BIAS, &lock->readers);
+
+       raw_spin_lock_irqsave(&m->wait_lock, flags);
+
+       raw_spin_lock(&self->pi_lock);
+       self->saved_state = self->state;
+       __set_current_state_no_track(TASK_UNINTERRUPTIBLE);
+       raw_spin_unlock(&self->pi_lock);
+
+       for (;;) {
+               /* Have all readers left the critical region? */
+               if (!atomic_read(&lock->readers)) {
+                       atomic_set(&lock->readers, WRITER_BIAS);
+                       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);
+                       raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+                       return;
+               }
+
+               raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+
+               if (atomic_read(&lock->readers) != 0)
+                       preempt_schedule_lock();
+
+               raw_spin_lock_irqsave(&m->wait_lock, flags);
+
+               raw_spin_lock(&self->pi_lock);
+               __set_current_state_no_track(TASK_UNINTERRUPTIBLE);
+               raw_spin_unlock(&self->pi_lock);
+       }
+}
+
+static int __write_rt_trylock(struct rt_rw_lock *lock)
+{
+       struct rt_mutex *m = &lock->rtmutex;
+       unsigned long flags;
+
+       if (!__rt_mutex_trylock(m))
+               return 0;
+
+       atomic_sub(READER_BIAS, &lock->readers);
+
+       raw_spin_lock_irqsave(&m->wait_lock, flags);
+       if (!atomic_read(&lock->readers)) {
+               atomic_set(&lock->readers, WRITER_BIAS);
+               raw_spin_unlock_irqrestore(&m->wait_lock, flags);
+               return 1;
+       }
+       __write_unlock_common(lock, 0, flags);
+       return 0;
+}
+
+static void __write_rt_unlock(struct rt_rw_lock *lock)
+{
+       struct rt_mutex *m = &lock->rtmutex;
+       unsigned long flags;
+
+       raw_spin_lock_irqsave(&m->wait_lock, flags);
+       __write_unlock_common(lock, WRITER_BIAS, flags);
+}
+
+int __lockfunc rt_read_can_lock(rwlock_t *rwlock)
+{
+       return  atomic_read(&rwlock->readers) < 0;
+}
+
+int __lockfunc rt_write_can_lock(rwlock_t *rwlock)
+{
+       return atomic_read(&rwlock->readers) == READER_BIAS;
+}
+
+/*
+ * The common functions which get wrapped into the rwlock API.
+ */
+int __lockfunc rt_read_trylock(rwlock_t *rwlock)
+{
+       int ret;
+
+       ret = __read_rt_trylock(rwlock);
+       if (ret) {
+               rwlock_acquire_read(&rwlock->dep_map, 0, 1, _RET_IP_);
+               rcu_read_lock();
+               migrate_disable();
+       }
+       return ret;
+}
+EXPORT_SYMBOL(rt_read_trylock);
+
+int __lockfunc rt_write_trylock(rwlock_t *rwlock)
+{
+       int ret;
+
+       ret = __write_rt_trylock(rwlock);
+       if (ret) {
+               rwlock_acquire(&rwlock->dep_map, 0, 1, _RET_IP_);
+               rcu_read_lock();
+               migrate_disable();
+       }
+       return ret;
+}
+EXPORT_SYMBOL(rt_write_trylock);
+
+void __lockfunc rt_read_lock(rwlock_t *rwlock)
+{
+       rwlock_acquire_read(&rwlock->dep_map, 0, 0, _RET_IP_);
+       __read_rt_lock(rwlock);
+       rcu_read_lock();
+       migrate_disable();
+}
+EXPORT_SYMBOL(rt_read_lock);
+
+void __lockfunc rt_write_lock(rwlock_t *rwlock)
+{
+       rwlock_acquire(&rwlock->dep_map, 0, 0, _RET_IP_);
+       __write_rt_lock(rwlock);
+       rcu_read_lock();
+       migrate_disable();
+}
+EXPORT_SYMBOL(rt_write_lock);
+
+void __lockfunc rt_read_unlock(rwlock_t *rwlock)
+{
+       rwlock_release(&rwlock->dep_map, _RET_IP_);
+       migrate_enable();
+       rcu_read_unlock();
+       __read_rt_unlock(rwlock);
+}
+EXPORT_SYMBOL(rt_read_unlock);
+
+void __lockfunc rt_write_unlock(rwlock_t *rwlock)
+{
+       rwlock_release(&rwlock->dep_map, _RET_IP_);
+       migrate_enable();
+       rcu_read_unlock();
+       __write_rt_unlock(rwlock);
+}
+EXPORT_SYMBOL(rt_write_unlock);
+
+void __rt_rwlock_init(rwlock_t *rwlock, char *name, struct lock_class_key *key)
+{
+       __rwlock_biased_rt_init(rwlock, name, key);
+}
+EXPORT_SYMBOL(__rt_rwlock_init);
diff --git a/kernel/locking/rwsem-rt.c b/kernel/locking/rwsem-rt.c
new file mode 100644 (file)
index 0000000..b61edc4
--- /dev/null
@@ -0,0 +1,317 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/rwsem.h>
+#include <linux/sched/debug.h>
+#include <linux/sched/signal.h>
+#include <linux/export.h>
+#include <linux/blkdev.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;
+}
+
+static int __sched __down_read_common(struct rw_semaphore *sem, int state)
+{
+       struct rt_mutex *m = &sem->rtmutex;
+       struct rt_mutex_waiter waiter;
+       int ret;
+
+       if (__down_read_trylock(sem))
+               return 0;
+
+       /*
+        * Flush blk before ->pi_blocked_on is set. At schedule() time it is too
+        * late if one of the callbacks needs to acquire a sleeping lock.
+        */
+       if (blk_needs_flush_plug(current))
+               blk_schedule_flush_plug(current);
+
+       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 0;
+       }
+
+       /*
+        * 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);
+       ret = rt_mutex_slowlock_locked(m, state, NULL, RT_MUTEX_MIN_CHAINWALK,
+                                      NULL, &waiter);
+       /*
+        * The slowlock() above is guaranteed to return with the rtmutex (for
+        * ret = 0) is now held, so there can't be a writer active. Increment
+        * the reader count and immediately drop the rtmutex again.
+        * For ret != 0 we don't hold the rtmutex and need unlock the wait_lock.
+        * We don't own the lock then.
+        */
+       if (!ret)
+               atomic_inc(&sem->readers);
+       raw_spin_unlock_irq(&m->wait_lock);
+       if (!ret)
+               __rt_mutex_unlock(m);
+
+       debug_rt_mutex_free_waiter(&waiter);
+       return ret;
+}
+
+void __down_read(struct rw_semaphore *sem)
+{
+       int ret;
+
+       ret = __down_read_common(sem, TASK_UNINTERRUPTIBLE);
+       WARN_ON_ONCE(ret);
+}
+
+int __down_read_interruptible(struct rw_semaphore *sem)
+{
+       int ret;
+
+       ret = __down_read_common(sem, TASK_INTERRUPTIBLE);
+       if (likely(!ret))
+               return ret;
+       WARN_ONCE(ret != -EINTR, "Unexpected state: %d\n", ret);
+       return -EINTR;
+}
+
+int __down_read_killable(struct rw_semaphore *sem)
+{
+       int ret;
+
+       ret = __down_read_common(sem, TASK_KILLABLE);
+       if (likely(!ret))
+               return ret;
+       WARN_ONCE(ret != -EINTR, "Unexpected state: %d\n", ret);
+       return -EINTR;
+}
+
+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;
+
+       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;
+
+       /*
+        * Flush blk before ->pi_blocked_on is set. At schedule() time it is too
+        * late if one of the callbacks needs to acquire a sleeping lock.
+        */
+       if (blk_needs_flush_plug(current))
+               blk_schedule_flush_plug(current);
+
+       /* 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 cc5cc88..f7c909e 100644 (file)
@@ -28,6 +28,7 @@
 #include <linux/rwsem.h>
 #include <linux/atomic.h>
 
+#ifndef CONFIG_PREEMPT_RT
 #include "lock_events.h"
 
 /*
@@ -1494,6 +1495,7 @@ static inline void __downgrade_write(struct rw_semaphore *sem)
        if (tmp & RWSEM_FLAG_WAITERS)
                rwsem_downgrade_wake(sem);
 }
+#endif
 
 /*
  * lock for reading
@@ -1657,7 +1659,9 @@ void down_read_non_owner(struct rw_semaphore *sem)
 {
        might_sleep();
        __down_read(sem);
+#ifndef CONFIG_PREEMPT_RT
        __rwsem_set_reader_owned(sem, NULL);
+#endif
 }
 EXPORT_SYMBOL(down_read_non_owner);
 
@@ -1686,7 +1690,9 @@ EXPORT_SYMBOL(down_write_killable_nested);
 
 void up_read_non_owner(struct rw_semaphore *sem)
 {
+#ifndef CONFIG_PREEMPT_RT
        DEBUG_RWSEMS_WARN_ON(!is_rwsem_reader_owned(sem), sem);
+#endif
        __up_read(sem);
 }
 EXPORT_SYMBOL(up_read_non_owner);
index 0ff0838..45445a2 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
 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
+
 #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 */
+
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 
 void __lockfunc _raw_spin_lock_nested(raw_spinlock_t *lock, int subclass)
index b9d9308..72e306e 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
 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)
 {
@@ -139,6 +141,7 @@ void do_raw_spin_unlock(raw_spinlock_t *lock)
        arch_spin_unlock(&lock->raw_lock);
 }
 
+#ifndef CONFIG_PREEMPT_RT
 static void rwlock_bug(rwlock_t *lock, const char *msg)
 {
        if (!debug_locks_off())
@@ -228,3 +231,5 @@ void do_raw_write_unlock(rwlock_t *lock)
        debug_write_unlock(lock);
        arch_write_unlock(&lock->raw_lock);
 }
+
+#endif
index 1b019cb..c20782f 100644 (file)
@@ -142,9 +142,9 @@ int atomic_notifier_chain_register(struct atomic_notifier_head *nh,
        unsigned long flags;
        int ret;
 
-       spin_lock_irqsave(&nh->lock, flags);
+       raw_spin_lock_irqsave(&nh->lock, flags);
        ret = notifier_chain_register(&nh->head, n);
-       spin_unlock_irqrestore(&nh->lock, flags);
+       raw_spin_unlock_irqrestore(&nh->lock, flags);
        return ret;
 }
 EXPORT_SYMBOL_GPL(atomic_notifier_chain_register);
@@ -164,9 +164,9 @@ int atomic_notifier_chain_unregister(struct atomic_notifier_head *nh,
        unsigned long flags;
        int ret;
 
-       spin_lock_irqsave(&nh->lock, flags);
+       raw_spin_lock_irqsave(&nh->lock, flags);
        ret = notifier_chain_unregister(&nh->head, n);
-       spin_unlock_irqrestore(&nh->lock, flags);
+       raw_spin_unlock_irqrestore(&nh->lock, flags);
        synchronize_rcu();
        return ret;
 }
@@ -182,9 +182,9 @@ int atomic_notifier_call_chain_robust(struct atomic_notifier_head *nh,
         * Musn't use RCU; because then the notifier list can
         * change between the up and down traversal.
         */
-       spin_lock_irqsave(&nh->lock, flags);
+       raw_spin_lock_irqsave(&nh->lock, flags);
        ret = notifier_call_chain_robust(&nh->head, val_up, val_down, v);
-       spin_unlock_irqrestore(&nh->lock, flags);
+       raw_spin_unlock_irqrestore(&nh->lock, flags);
 
        return ret;
 }
index 332736a..a14e2f5 100644 (file)
@@ -177,12 +177,28 @@ static void panic_print_sys_info(void)
 void panic(const char *fmt, ...)
 {
        static char buf[1024];
+       va_list args2;
        va_list args;
        long i, i_next = 0, len;
        int state = 0;
        int old_cpu, this_cpu;
        bool _crash_kexec_post_notifiers = crash_kexec_post_notifiers;
 
+       console_verbose();
+       pr_emerg("Kernel panic - not syncing:\n");
+       va_start(args2, fmt);
+       va_copy(args, args2);
+       vprintk(fmt, args2);
+       va_end(args2);
+#ifdef CONFIG_DEBUG_BUGVERBOSE
+       /*
+        * Avoid nested stack-dumping if a panic occurs during oops processing
+        */
+       if (!test_taint(TAINT_DIE) && oops_in_progress <= 1)
+               dump_stack();
+#endif
+       pr_flush(1000, true);
+
        /*
         * Disable local interrupts. This will prevent panic_smp_self_stop
         * from deadlocking the first cpu that invokes the panic, since
@@ -213,24 +229,13 @@ void panic(const char *fmt, ...)
        if (old_cpu != PANIC_CPU_INVALID && old_cpu != this_cpu)
                panic_smp_self_stop();
 
-       console_verbose();
        bust_spinlocks(1);
-       va_start(args, fmt);
        len = vscnprintf(buf, sizeof(buf), fmt, args);
        va_end(args);
 
        if (len && buf[len - 1] == '\n')
                buf[len - 1] = '\0';
 
-       pr_emerg("Kernel panic - not syncing: %s\n", buf);
-#ifdef CONFIG_DEBUG_BUGVERBOSE
-       /*
-        * Avoid nested stack-dumping if a panic occurs during oops processing
-        */
-       if (!test_taint(TAINT_DIE) && oops_in_progress <= 1)
-               dump_stack();
-#endif
-
        /*
         * If kgdb is enabled, give it a chance to run before we stop all
         * the other CPUs or else we won't be able to debug processes left
@@ -247,7 +252,6 @@ void panic(const char *fmt, ...)
         * Bypass the panic_cpu check and call __crash_kexec directly.
         */
        if (!_crash_kexec_post_notifiers) {
-               printk_safe_flush_on_panic();
                __crash_kexec(NULL);
 
                /*
@@ -271,8 +275,6 @@ void panic(const char *fmt, ...)
         */
        atomic_notifier_call_chain(&panic_notifier_list, 0, buf);
 
-       /* Call flush even twice. It tries harder with a single online CPU */
-       printk_safe_flush_on_panic();
        kmsg_dump(KMSG_DUMP_PANIC);
 
        /*
@@ -542,9 +544,11 @@ static u64 oops_id;
 
 static int init_oops_id(void)
 {
+#ifndef CONFIG_PREEMPT_RT
        if (!oops_id)
                get_random_bytes(&oops_id, sizeof(oops_id));
        else
+#endif
                oops_id++;
 
        return 0;
@@ -555,6 +559,7 @@ static void print_oops_end_marker(void)
 {
        init_oops_id();
        pr_warn("---[ end trace %016llx ]---\n", (unsigned long long)oops_id);
+       pr_flush(1000, true);
 }
 
 /*
index eee3dc9..59cb24e 100644 (file)
@@ -1,5 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0-only
 obj-y  = printk.o
-obj-$(CONFIG_PRINTK)   += printk_safe.o
 obj-$(CONFIG_A11Y_BRAILLE_CONSOLE)     += braille.o
 obj-$(CONFIG_PRINTK)   += printk_ringbuffer.o
diff --git a/kernel/printk/internal.h b/kernel/printk/internal.h
deleted file mode 100644 (file)
index 3a8fd49..0000000
+++ /dev/null
@@ -1,74 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-or-later */
-/*
- * internal.h - printk internal definitions
- */
-#include <linux/percpu.h>
-
-#ifdef CONFIG_PRINTK
-
-#define PRINTK_SAFE_CONTEXT_MASK       0x007ffffff
-#define PRINTK_NMI_DIRECT_CONTEXT_MASK 0x008000000
-#define PRINTK_NMI_CONTEXT_MASK                0xff0000000
-
-#define PRINTK_NMI_CONTEXT_OFFSET      0x010000000
-
-extern raw_spinlock_t logbuf_lock;
-
-__printf(4, 0)
-int vprintk_store(int facility, int level,
-                 const struct dev_printk_info *dev_info,
-                 const char *fmt, va_list args);
-
-__printf(1, 0) int vprintk_default(const char *fmt, va_list args);
-__printf(1, 0) int vprintk_deferred(const char *fmt, va_list args);
-__printf(1, 0) int vprintk_func(const char *fmt, va_list args);
-void __printk_safe_enter(void);
-void __printk_safe_exit(void);
-
-void printk_safe_init(void);
-bool printk_percpu_data_ready(void);
-
-#define printk_safe_enter_irqsave(flags)       \
-       do {                                    \
-               local_irq_save(flags);          \
-               __printk_safe_enter();          \
-       } while (0)
-
-#define printk_safe_exit_irqrestore(flags)     \
-       do {                                    \
-               __printk_safe_exit();           \
-               local_irq_restore(flags);       \
-       } while (0)
-
-#define printk_safe_enter_irq()                \
-       do {                                    \
-               local_irq_disable();            \
-               __printk_safe_enter();          \
-       } while (0)
-
-#define printk_safe_exit_irq()                 \
-       do {                                    \
-               __printk_safe_exit();           \
-               local_irq_enable();             \
-       } while (0)
-
-void defer_console_output(void);
-
-#else
-
-__printf(1, 0) int vprintk_func(const char *fmt, va_list args) { return 0; }
-
-/*
- * In !PRINTK builds we still export logbuf_lock spin_lock, console_sem
- * semaphore and some of console functions (console_unlock()/etc.), so
- * printk-safe must preserve the existing local IRQ guarantees.
- */
-#define printk_safe_enter_irqsave(flags) local_irq_save(flags)
-#define printk_safe_exit_irqrestore(flags) local_irq_restore(flags)
-
-#define printk_safe_enter_irq() local_irq_disable()
-#define printk_safe_exit_irq() local_irq_enable()
-
-static inline void printk_safe_init(void) { }
-static inline bool printk_percpu_data_ready(void) { return false; }
-#endif /* CONFIG_PRINTK */
index 85351a1..dea500d 100644 (file)
@@ -44,6 +44,9 @@
 #include <linux/irq_work.h>
 #include <linux/ctype.h>
 #include <linux/uio.h>
+#include <linux/kthread.h>
+#include <linux/kdb.h>
+#include <linux/clocksource.h>
 #include <linux/sched/clock.h>
 #include <linux/sched/debug.h>
 #include <linux/sched/task_stack.h>
@@ -58,7 +61,6 @@
 #include "printk_ringbuffer.h"
 #include "console_cmdline.h"
 #include "braille.h"
-#include "internal.h"
 
 int console_printk[4] = {
        CONSOLE_LOGLEVEL_DEFAULT,       /* console_loglevel */
@@ -225,19 +227,7 @@ static int nr_ext_console_drivers;
 
 static int __down_trylock_console_sem(unsigned long ip)
 {
-       int lock_failed;
-       unsigned long flags;
-
-       /*
-        * Here and in __up_console_sem() we need to be in safe mode,
-        * because spindump/WARN/etc from under console ->lock will
-        * deadlock in printk()->down_trylock_console_sem() otherwise.
-        */
-       printk_safe_enter_irqsave(flags);
-       lock_failed = down_trylock(&console_sem);
-       printk_safe_exit_irqrestore(flags);
-
-       if (lock_failed)
+       if (down_trylock(&console_sem))
                return 1;
        mutex_acquire(&console_lock_dep_map, 0, 1, ip);
        return 0;
@@ -246,13 +236,9 @@ static int __down_trylock_console_sem(unsigned long ip)
 
 static void __up_console_sem(unsigned long ip)
 {
-       unsigned long flags;
-
        mutex_release(&console_lock_dep_map, ip);
 
-       printk_safe_enter_irqsave(flags);
        up(&console_sem);
-       printk_safe_exit_irqrestore(flags);
 }
 #define up_console_sem() __up_console_sem(_RET_IP_)
 
@@ -267,11 +253,6 @@ static void __up_console_sem(unsigned long ip)
 static int console_locked, console_suspended;
 
 /*
- * If exclusive_console is non-NULL then only this console is to be printed to.
- */
-static struct console *exclusive_console;
-
-/*
  *     Array of consoles built from command line options (console=)
  */
 
@@ -355,61 +336,43 @@ enum log_flags {
        LOG_CONT        = 8,    /* text is a fragment of a continuation line */
 };
 
-/*
- * The logbuf_lock protects kmsg buffer, indices, counters.  This can be taken
- * within the scheduler's rq lock. It must be released before calling
- * console_unlock() or anything else that might wake up a process.
- */
-DEFINE_RAW_SPINLOCK(logbuf_lock);
+#ifdef CONFIG_PRINTK
+/* syslog_lock protects syslog_* variables and write access to clear_seq. */
+static DEFINE_SPINLOCK(syslog_lock);
 
-/*
- * Helper macros to lock/unlock logbuf_lock and switch between
- * printk-safe/unsafe modes.
- */
-#define logbuf_lock_irq()                              \
-       do {                                            \
-               printk_safe_enter_irq();                \
-               raw_spin_lock(&logbuf_lock);            \
-       } while (0)
-
-#define logbuf_unlock_irq()                            \
-       do {                                            \
-               raw_spin_unlock(&logbuf_lock);          \
-               printk_safe_exit_irq();                 \
-       } while (0)
-
-#define logbuf_lock_irqsave(flags)                     \
-       do {                                            \
-               printk_safe_enter_irqsave(flags);       \
-               raw_spin_lock(&logbuf_lock);            \
-       } while (0)
-
-#define logbuf_unlock_irqrestore(flags)                \
-       do {                                            \
-               raw_spin_unlock(&logbuf_lock);          \
-               printk_safe_exit_irqrestore(flags);     \
-       } while (0)
+/* Set to enable sync mode. Once set, it is never cleared. */
+static bool sync_mode;
 
-#ifdef CONFIG_PRINTK
 DECLARE_WAIT_QUEUE_HEAD(log_wait);
+/* All 3 protected by @syslog_lock. */
 /* the next printk record to read by syslog(READ) or /proc/kmsg */
 static u64 syslog_seq;
 static size_t syslog_partial;
 static bool syslog_time;
 
-/* the next printk record to write to the console */
-static u64 console_seq;
-static u64 exclusive_console_stop_seq;
-static unsigned long console_dropped;
+struct latched_seq {
+       seqcount_latch_t        latch;
+       u64                     val[2];
+};
 
-/* the next printk record to read after the last 'clear' command */
-static u64 clear_seq;
+/*
+ * The next printk record to read after the last 'clear' command. There are
+ * two copies (updated with seqcount_latch) so that reads can locklessly
+ * access a valid value. Writers are synchronized by @syslog_lock.
+ */
+static struct latched_seq clear_seq = {
+       .latch          = SEQCNT_LATCH_ZERO(clear_seq.latch),
+       .val[0]         = 0,
+       .val[1]         = 0,
+};
 
 #ifdef CONFIG_PRINTK_CALLER
 #define PREFIX_MAX             48
 #else
 #define PREFIX_MAX             32
 #endif
+
+/* the maximum size allowed to be reserved for a record */
 #define LOG_LINE_MAX           (1024 - PREFIX_MAX)
 
 #define LOG_LEVEL(v)           ((v) & 0x07)
@@ -447,11 +410,36 @@ static struct printk_ringbuffer *prb = &printk_rb_static;
  */
 static bool __printk_percpu_data_ready __read_mostly;
 
-bool printk_percpu_data_ready(void)
+static bool printk_percpu_data_ready(void)
 {
        return __printk_percpu_data_ready;
 }
 
+/* Must be called under syslog_lock. */
+static void latched_seq_write(struct latched_seq *ls, u64 val)
+{
+       raw_write_seqcount_latch(&ls->latch);
+       ls->val[0] = val;
+       raw_write_seqcount_latch(&ls->latch);
+       ls->val[1] = val;
+}
+
+/* Can be called from any context. */
+static u64 latched_seq_read_nolock(struct latched_seq *ls)
+{
+       unsigned int seq;
+       unsigned int idx;
+       u64 val;
+
+       do {
+               seq = raw_read_seqcount_latch(&ls->latch);
+               idx = seq & 0x1;
+               val = ls->val[idx];
+       } while (read_seqcount_latch_retry(&ls->latch, seq));
+
+       return val;
+}
+
 /* Return log buffer address */
 char *log_buf_addr_get(void)
 {
@@ -491,52 +479,6 @@ static void truncate_msg(u16 *text_len, u16 *trunc_msg_len)
                *trunc_msg_len = 0;
 }
 
-/* insert record into the buffer, discard old ones, update heads */
-static int log_store(u32 caller_id, int facility, int level,
-                    enum log_flags flags, u64 ts_nsec,
-                    const struct dev_printk_info *dev_info,
-                    const char *text, u16 text_len)
-{
-       struct prb_reserved_entry e;
-       struct printk_record r;
-       u16 trunc_msg_len = 0;
-
-       prb_rec_init_wr(&r, text_len);
-
-       if (!prb_reserve(&e, prb, &r)) {
-               /* truncate the message if it is too long for empty buffer */
-               truncate_msg(&text_len, &trunc_msg_len);
-               prb_rec_init_wr(&r, text_len + trunc_msg_len);
-               /* survive when the log buffer is too small for trunc_msg */
-               if (!prb_reserve(&e, prb, &r))
-                       return 0;
-       }
-
-       /* fill message */
-       memcpy(&r.text_buf[0], text, text_len);
-       if (trunc_msg_len)
-               memcpy(&r.text_buf[text_len], trunc_msg, trunc_msg_len);
-       r.info->text_len = text_len + trunc_msg_len;
-       r.info->facility = facility;
-       r.info->level = level & 7;
-       r.info->flags = flags & 0x1f;
-       if (ts_nsec > 0)
-               r.info->ts_nsec = ts_nsec;
-       else
-               r.info->ts_nsec = local_clock();
-       r.info->caller_id = caller_id;
-       if (dev_info)
-               memcpy(&r.info->dev_info, dev_info, sizeof(r.info->dev_info));
-
-       /* A message without a trailing newline can be continued. */
-       if (!(flags & LOG_NEWLINE))
-               prb_commit(&e);
-       else
-               prb_final_commit(&e);
-
-       return (text_len + trunc_msg_len);
-}
-
 int dmesg_restrict = IS_ENABLED(CONFIG_SECURITY_DMESG_RESTRICT);
 
 static int syslog_action_restricted(int type)
@@ -665,7 +607,7 @@ out:
 
 /* /dev/kmsg - userspace message inject/listen interface */
 struct devkmsg_user {
-       u64 seq;
+       atomic64_t seq;
        struct ratelimit_state rs;
        struct mutex lock;
        char buf[CONSOLE_EXT_LOG_MAX];
@@ -766,27 +708,22 @@ static ssize_t devkmsg_read(struct file *file, char __user *buf,
        if (ret)
                return ret;
 
-       logbuf_lock_irq();
-       if (!prb_read_valid(prb, user->seq, r)) {
+       if (!prb_read_valid(prb, atomic64_read(&user->seq), r)) {
                if (file->f_flags & O_NONBLOCK) {
                        ret = -EAGAIN;
-                       logbuf_unlock_irq();
                        goto out;
                }
 
-               logbuf_unlock_irq();
                ret = wait_event_interruptible(log_wait,
-                                       prb_read_valid(prb, user->seq, r));
+                               prb_read_valid(prb, atomic64_read(&user->seq), r));
                if (ret)
                        goto out;
-               logbuf_lock_irq();
        }
 
-       if (r->info->seq != user->seq) {
+       if (r->info->seq != atomic64_read(&user->seq)) {
                /* our last seen message is gone, return error and reset */
-               user->seq = r->info->seq;
+               atomic64_set(&user->seq, r->info->seq);
                ret = -EPIPE;
-               logbuf_unlock_irq();
                goto out;
        }
 
@@ -795,8 +732,7 @@ static ssize_t devkmsg_read(struct file *file, char __user *buf,
                                  &r->text_buf[0], r->info->text_len,
                                  &r->info->dev_info);
 
-       user->seq = r->info->seq + 1;
-       logbuf_unlock_irq();
+       atomic64_set(&user->seq, r->info->seq + 1);
 
        if (len > count) {
                ret = -EINVAL;
@@ -831,11 +767,10 @@ static loff_t devkmsg_llseek(struct file *file, loff_t offset, int whence)
        if (offset)
                return -ESPIPE;
 
-       logbuf_lock_irq();
        switch (whence) {
        case SEEK_SET:
                /* the first record */
-               user->seq = prb_first_valid_seq(prb);
+               atomic64_set(&user->seq, prb_first_valid_seq(prb));
                break;
        case SEEK_DATA:
                /*
@@ -843,16 +778,15 @@ static loff_t devkmsg_llseek(struct file *file, loff_t offset, int whence)
                 * like issued by 'dmesg -c'. Reading /dev/kmsg itself
                 * changes no global state, and does not clear anything.
                 */
-               user->seq = clear_seq;
+               atomic64_set(&user->seq, latched_seq_read_nolock(&clear_seq));
                break;
        case SEEK_END:
                /* after the last record */
-               user->seq = prb_next_seq(prb);
+               atomic64_set(&user->seq, prb_next_seq(prb));
                break;
        default:
                ret = -EINVAL;
        }
-       logbuf_unlock_irq();
        return ret;
 }
 
@@ -867,15 +801,13 @@ static __poll_t devkmsg_poll(struct file *file, poll_table *wait)
 
        poll_wait(file, &log_wait, wait);
 
-       logbuf_lock_irq();
-       if (prb_read_valid_info(prb, user->seq, &info, NULL)) {
+       if (prb_read_valid_info(prb, atomic64_read(&user->seq), &info, NULL)) {
                /* return error when data has vanished underneath us */
-               if (info.seq != user->seq)
+               if (info.seq != atomic64_read(&user->seq))
                        ret = EPOLLIN|EPOLLRDNORM|EPOLLERR|EPOLLPRI;
                else
                        ret = EPOLLIN|EPOLLRDNORM;
        }
-       logbuf_unlock_irq();
 
        return ret;
 }
@@ -908,9 +840,7 @@ static int devkmsg_open(struct inode *inode, struct file *file)
        prb_rec_init_rd(&user->record, &user->info,
                        &user->text_buf[0], sizeof(user->text_buf));
 
-       logbuf_lock_irq();
-       user->seq = prb_first_valid_seq(prb);
-       logbuf_unlock_irq();
+       atomic64_set(&user->seq, prb_first_valid_seq(prb));
 
        file->private_data = user;
        return 0;
@@ -1002,6 +932,9 @@ void log_buf_vmcoreinfo_setup(void)
 
        VMCOREINFO_SIZE(atomic_long_t);
        VMCOREINFO_TYPE_OFFSET(atomic_long_t, counter);
+
+       VMCOREINFO_STRUCT_SIZE(latched_seq);
+       VMCOREINFO_OFFSET(latched_seq, val);
 }
 #endif
 
@@ -1073,9 +1006,6 @@ static inline void log_buf_add_cpu(void) {}
 
 static void __init set_percpu_data_ready(void)
 {
-       printk_safe_init();
-       /* Make sure we set this flag only after printk_safe() init is done */
-       barrier();
        __printk_percpu_data_ready = true;
 }
 
@@ -1115,7 +1045,6 @@ void __init setup_log_buf(int early)
        struct printk_record r;
        size_t new_descs_size;
        size_t new_infos_size;
-       unsigned long flags;
        char *new_log_buf;
        unsigned int free;
        u64 seq;
@@ -1173,8 +1102,6 @@ void __init setup_log_buf(int early)
                 new_descs, ilog2(new_descs_count),
                 new_infos);
 
-       logbuf_lock_irqsave(flags);
-
        log_buf_len = new_log_buf_len;
        log_buf = new_log_buf;
        new_log_buf_len = 0;
@@ -1190,8 +1117,6 @@ void __init setup_log_buf(int early)
         */
        prb = &printk_rb_dynamic;
 
-       logbuf_unlock_irqrestore(flags);
-
        if (seq != prb_next_seq(&printk_rb_static)) {
                pr_err("dropped %llu messages\n",
                       prb_next_seq(&printk_rb_static) - seq);
@@ -1468,6 +1393,50 @@ static size_t get_record_print_text_size(struct printk_info *info,
        return ((prefix_len * line_count) + info->text_len + 1);
 }
 
+/*
+ * Beginning with @start_seq, find the first record where it and all following
+ * records up to (but not including) @max_seq fit into @size.
+ *
+ * @max_seq is simply an upper bound and does not need to exist. If the caller
+ * does not require an upper bound, -1 can be used for @max_seq.
+ */
+static u64 find_first_fitting_seq(u64 start_seq, u64 max_seq, size_t size,
+                                 bool syslog, bool time)
+{
+       struct printk_info info;
+       unsigned int line_count;
+       size_t len = 0;
+       u64 seq;
+
+       /* Determine the size of the records up to @max_seq. */
+       prb_for_each_info(start_seq, prb, seq, &info, &line_count) {
+               if (info.seq >= max_seq)
+                       break;
+               len += get_record_print_text_size(&info, line_count, syslog, time);
+       }
+
+       /*
+        * Adjust the upper bound for the next loop to avoid subtracting
+        * lengths that were never added.
+        */
+       if (seq < max_seq)
+               max_seq = seq;
+
+       /*
+        * Move first record forward until length fits into the buffer. Ignore
+        * newest messages that were not counted in the above cycle. Messages
+        * might appear and get lost in the meantime. This is a best effort
+        * that prevents an infinite loop that could occur with a retry.
+        */
+       prb_for_each_info(start_seq, prb, seq, &info, &line_count) {
+               if (len <= size || info.seq >= max_seq)
+                       break;
+               len -= get_record_print_text_size(&info, line_count, syslog, time);
+       }
+
+       return seq;
+}
+
 static int syslog_print(char __user *buf, int size)
 {
        struct printk_info info;
@@ -1475,19 +1444,19 @@ static int syslog_print(char __user *buf, int size)
        char *text;
        int len = 0;
 
-       text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);
+       text = kmalloc(CONSOLE_LOG_MAX, GFP_KERNEL);
        if (!text)
                return -ENOMEM;
 
-       prb_rec_init_rd(&r, &info, text, LOG_LINE_MAX + PREFIX_MAX);
+       prb_rec_init_rd(&r, &info, text, CONSOLE_LOG_MAX);
 
        while (size > 0) {
                size_t n;
                size_t skip;
 
-               logbuf_lock_irq();
+               spin_lock_irq(&syslog_lock);
                if (!prb_read_valid(prb, syslog_seq, &r)) {
-                       logbuf_unlock_irq();
+                       spin_unlock_irq(&syslog_lock);
                        break;
                }
                if (r.info->seq != syslog_seq) {
@@ -1516,7 +1485,7 @@ static int syslog_print(char __user *buf, int size)
                        syslog_partial += n;
                } else
                        n = 0;
-               logbuf_unlock_irq();
+               spin_unlock_irq(&syslog_lock);
 
                if (!n)
                        break;
@@ -1539,34 +1508,25 @@ static int syslog_print(char __user *buf, int size)
 static int syslog_print_all(char __user *buf, int size, bool clear)
 {
        struct printk_info info;
-       unsigned int line_count;
        struct printk_record r;
        char *text;
        int len = 0;
        u64 seq;
        bool time;
 
-       text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);
+       text = kmalloc(CONSOLE_LOG_MAX, GFP_KERNEL);
        if (!text)
                return -ENOMEM;
 
        time = printk_time;
-       logbuf_lock_irq();
        /*
         * Find first record that fits, including all following records,
         * into the user-provided buffer for this dump.
         */
-       prb_for_each_info(clear_seq, prb, seq, &info, &line_count)
-               len += get_record_print_text_size(&info, line_count, true, time);
-
-       /* move first record forward until length fits into the buffer */
-       prb_for_each_info(clear_seq, prb, seq, &info, &line_count) {
-               if (len <= size)
-                       break;
-               len -= get_record_print_text_size(&info, line_count, true, time);
-       }
+       seq = find_first_fitting_seq(latched_seq_read_nolock(&clear_seq), -1,
+                                    size, true, time);
 
-       prb_rec_init_rd(&r, &info, text, LOG_LINE_MAX + PREFIX_MAX);
+       prb_rec_init_rd(&r, &info, text, CONSOLE_LOG_MAX);
 
        len = 0;
        prb_for_each_record(seq, prb, seq, &r) {
@@ -1579,20 +1539,20 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
                        break;
                }
 
-               logbuf_unlock_irq();
                if (copy_to_user(buf + len, text, textlen))
                        len = -EFAULT;
                else
                        len += textlen;
-               logbuf_lock_irq();
 
                if (len < 0)
                        break;
        }
 
-       if (clear)
-               clear_seq = seq;
-       logbuf_unlock_irq();
+       if (clear) {
+               spin_lock_irq(&syslog_lock);
+               latched_seq_write(&clear_seq, seq);
+               spin_unlock_irq(&syslog_lock);
+       }
 
        kfree(text);
        return len;
@@ -1600,9 +1560,21 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
 
 static void syslog_clear(void)
 {
-       logbuf_lock_irq();
-       clear_seq = prb_next_seq(prb);
-       logbuf_unlock_irq();
+       spin_lock_irq(&syslog_lock);
+       latched_seq_write(&clear_seq, prb_next_seq(prb));
+       spin_unlock_irq(&syslog_lock);
+}
+
+/* Return a consistent copy of @syslog_seq. */
+static u64 read_syslog_seq_irq(void)
+{
+       u64 seq;
+
+       spin_lock_irq(&syslog_lock);
+       seq = syslog_seq;
+       spin_unlock_irq(&syslog_lock);
+
+       return seq;
 }
 
 int do_syslog(int type, char __user *buf, int len, int source)
@@ -1628,8 +1600,9 @@ int do_syslog(int type, char __user *buf, int len, int source)
                        return 0;
                if (!access_ok(buf, len))
                        return -EFAULT;
+
                error = wait_event_interruptible(log_wait,
-                               prb_read_valid(prb, syslog_seq, NULL));
+                               prb_read_valid(prb, read_syslog_seq_irq(), NULL));
                if (error)
                        return error;
                error = syslog_print(buf, len);
@@ -1677,10 +1650,10 @@ int do_syslog(int type, char __user *buf, int len, int source)
                break;
        /* Number of chars in the log buffer */
        case SYSLOG_ACTION_SIZE_UNREAD:
-               logbuf_lock_irq();
+               spin_lock_irq(&syslog_lock);
                if (!prb_read_valid_info(prb, syslog_seq, &info, NULL)) {
                        /* No unread messages. */
-                       logbuf_unlock_irq();
+                       spin_unlock_irq(&syslog_lock);
                        return 0;
                }
                if (info.seq != syslog_seq) {
@@ -1708,7 +1681,7 @@ int do_syslog(int type, char __user *buf, int len, int source)
                        }
                        error -= syslog_partial;
                }
-               logbuf_unlock_irq();
+               spin_unlock_irq(&syslog_lock);
                break;
        /* Size of the log buffer */
        case SYSLOG_ACTION_SIZE_BUFFER:
@@ -1727,202 +1700,172 @@ SYSCALL_DEFINE3(syslog, int, type, char __user *, buf, int, len)
        return do_syslog(type, buf, len, SYSLOG_FROM_READER);
 }
 
-/*
- * Special console_lock variants that help to reduce the risk of soft-lockups.
- * They allow to pass console_lock to another printk() call using a busy wait.
- */
-
-#ifdef CONFIG_LOCKDEP
-static struct lockdep_map console_owner_dep_map = {
-       .name = "console_owner"
-};
-#endif
-
-static DEFINE_RAW_SPINLOCK(console_owner_lock);
-static struct task_struct *console_owner;
-static bool console_waiter;
+int printk_delay_msec __read_mostly;
 
-/**
- * console_lock_spinning_enable - mark beginning of code where another
- *     thread might safely busy wait
- *
- * This basically converts console_lock into a spinlock. This marks
- * the section where the console_lock owner can not sleep, because
- * there may be a waiter spinning (like a spinlock). Also it must be
- * ready to hand over the lock at the end of the section.
- */
-static void console_lock_spinning_enable(void)
+static inline void printk_delay(int level)
 {
-       raw_spin_lock(&console_owner_lock);
-       console_owner = current;
-       raw_spin_unlock(&console_owner_lock);
+       boot_delay_msec(level);
+
+       if (unlikely(printk_delay_msec)) {
+               int m = printk_delay_msec;
 
-       /* The waiter may spin on us after setting console_owner */
-       spin_acquire(&console_owner_dep_map, 0, 0, _THIS_IP_);
+               while (m--) {
+                       mdelay(1);
+                       touch_nmi_watchdog();
+               }
+       }
 }
 
-/**
- * console_lock_spinning_disable_and_check - mark end of code where another
- *     thread was able to busy wait and check if there is a waiter
- *
- * This is called at the end of the section where spinning is allowed.
- * It has two functions. First, it is a signal that it is no longer
- * safe to start busy waiting for the lock. Second, it checks if
- * there is a busy waiter and passes the lock rights to her.
- *
- * Important: Callers lose the lock if there was a busy waiter.
- *     They must not touch items synchronized by console_lock
- *     in this case.
- *
- * Return: 1 if the lock rights were passed, 0 otherwise.
- */
-static int console_lock_spinning_disable_and_check(void)
+static bool kernel_sync_mode(void)
 {
-       int waiter;
+       return (oops_in_progress || sync_mode);
+}
 
-       raw_spin_lock(&console_owner_lock);
-       waiter = READ_ONCE(console_waiter);
-       console_owner = NULL;
-       raw_spin_unlock(&console_owner_lock);
+static bool console_can_sync(struct console *con)
+{
+       if (!(con->flags & CON_ENABLED))
+               return false;
+       if (con->write_atomic && kernel_sync_mode())
+               return true;
+       if (con->write_atomic && (con->flags & CON_HANDOVER) && !con->thread)
+               return true;
+       if (con->write && (con->flags & CON_BOOT) && !con->thread)
+               return true;
+       return false;
+}
 
-       if (!waiter) {
-               spin_release(&console_owner_dep_map, _THIS_IP_);
-               return 0;
-       }
+static bool call_sync_console_driver(struct console *con, const char *text, size_t text_len)
+{
+       if (!(con->flags & CON_ENABLED))
+               return false;
+       if (con->write_atomic && kernel_sync_mode())
+               con->write_atomic(con, text, text_len);
+       else if (con->write_atomic && (con->flags & CON_HANDOVER) && !con->thread)
+               con->write_atomic(con, text, text_len);
+       else if (con->write && (con->flags & CON_BOOT) && !con->thread)
+               con->write(con, text, text_len);
+       else
+               return false;
 
-       /* The waiter is now free to continue */
-       WRITE_ONCE(console_waiter, false);
+       return true;
+}
 
-       spin_release(&console_owner_dep_map, _THIS_IP_);
+static bool have_atomic_console(void)
+{
+       struct console *con;
 
-       /*
-        * Hand off console_lock to waiter. The waiter will perform
-        * the up(). After this, the waiter is the console_lock owner.
-        */
-       mutex_release(&console_lock_dep_map, _THIS_IP_);
-       return 1;
+       for_each_console(con) {
+               if (!(con->flags & CON_ENABLED))
+                       continue;
+               if (con->write_atomic)
+                       return true;
+       }
+       return false;
 }
 
-/**
- * console_trylock_spinning - try to get console_lock by busy waiting
- *
- * This allows to busy wait for the console_lock when the current
- * owner is running in specially marked sections. It means that
- * the current owner is running and cannot reschedule until it
- * is ready to lose the lock.
- *
- * Return: 1 if we got the lock, 0 othrewise
- */
-static int console_trylock_spinning(void)
+static bool print_sync(struct console *con, u64 *seq)
 {
-       struct task_struct *owner = NULL;
-       bool waiter;
-       bool spin = false;
-       unsigned long flags;
+       struct printk_info info;
+       struct printk_record r;
+       size_t text_len;
 
-       if (console_trylock())
-               return 1;
+       prb_rec_init_rd(&r, &info, &con->sync_buf[0], sizeof(con->sync_buf));
 
-       printk_safe_enter_irqsave(flags);
+       if (!prb_read_valid(prb, *seq, &r))
+               return false;
 
-       raw_spin_lock(&console_owner_lock);
-       owner = READ_ONCE(console_owner);
-       waiter = READ_ONCE(console_waiter);
-       if (!waiter && owner && owner != current) {
-               WRITE_ONCE(console_waiter, true);
-               spin = true;
-       }
-       raw_spin_unlock(&console_owner_lock);
+       text_len = record_print_text(&r, console_msg_format & MSG_FORMAT_SYSLOG, printk_time);
 
-       /*
-        * If there is an active printk() writing to the
-        * consoles, instead of having it write our data too,
-        * see if we can offload that load from the active
-        * printer, and do some printing ourselves.
-        * Go into a spin only if there isn't already a waiter
-        * spinning, and there is an active printer, and
-        * that active printer isn't us (recursive printk?).
-        */
-       if (!spin) {
-               printk_safe_exit_irqrestore(flags);
-               return 0;
-       }
+       if (!call_sync_console_driver(con, &con->sync_buf[0], text_len))
+               return false;
 
-       /* We spin waiting for the owner to release us */
-       spin_acquire(&console_owner_dep_map, 0, 0, _THIS_IP_);
-       /* Owner will clear console_waiter on hand off */
-       while (READ_ONCE(console_waiter))
-               cpu_relax();
-       spin_release(&console_owner_dep_map, _THIS_IP_);
+       *seq = r.info->seq;
 
-       printk_safe_exit_irqrestore(flags);
-       /*
-        * The owner passed the console lock to us.
-        * Since we did not spin on console lock, annotate
-        * this as a trylock. Otherwise lockdep will
-        * complain.
-        */
-       mutex_acquire(&console_lock_dep_map, 0, 1, _THIS_IP_);
+       touch_softlockup_watchdog_sync();
+       clocksource_touch_watchdog();
+       rcu_cpu_stall_reset();
+       touch_nmi_watchdog();
 
-       return 1;
+       if (text_len)
+               printk_delay(r.info->level);
+
+       return true;
 }
 
-/*
- * Call the console drivers, asking them to write out
- * log_buf[start] to log_buf[end - 1].
- * The console_lock must be held.
- */
-static void call_console_drivers(const char *ext_text, size_t ext_len,
-                                const char *text, size_t len)
+static void print_sync_until(struct console *con, u64 seq)
 {
-       static char dropped_text[64];
-       size_t dropped_len = 0;
-       struct console *con;
+       unsigned int flags;
+       u64 printk_seq;
+
+       console_atomic_lock(&flags);
+       for (;;) {
+               printk_seq = atomic64_read(&con->printk_seq);
+               if (printk_seq >= seq)
+                       break;
+               if (!print_sync(con, &printk_seq))
+                       break;
+               atomic64_set(&con->printk_seq, printk_seq + 1);
+       }
+       console_atomic_unlock(flags);
+}
 
-       trace_console_rcuidle(text, len);
+#ifdef CONFIG_PRINTK_NMI
+#define NUM_RECURSION_CTX 2
+#else
+#define NUM_RECURSION_CTX 1
+#endif
 
-       if (!console_drivers)
-               return;
+struct printk_recursion {
+       char    count[NUM_RECURSION_CTX];
+};
 
-       if (console_dropped) {
-               dropped_len = snprintf(dropped_text, sizeof(dropped_text),
-                                      "** %lu printk messages dropped **\n",
-                                      console_dropped);
-               console_dropped = 0;
-       }
+static DEFINE_PER_CPU(struct printk_recursion, percpu_printk_recursion);
+static char printk_recursion_count[NUM_RECURSION_CTX];
 
-       for_each_console(con) {
-               if (exclusive_console && con != exclusive_console)
-                       continue;
-               if (!(con->flags & CON_ENABLED))
-                       continue;
-               if (!con->write)
-                       continue;
-               if (!cpu_online(smp_processor_id()) &&
-                   !(con->flags & CON_ANYTIME))
-                       continue;
-               if (con->flags & CON_EXTENDED)
-                       con->write(con, ext_text, ext_len);
-               else {
-                       if (dropped_len)
-                               con->write(con, dropped_text, dropped_len);
-                       con->write(con, text, len);
-               }
+static char *printk_recursion_counter(void)
+{
+       struct printk_recursion *rec;
+       char *count;
+
+       if (!printk_percpu_data_ready()) {
+               count = &printk_recursion_count[0];
+       } else {
+               rec = this_cpu_ptr(&percpu_printk_recursion);
+
+               count = &rec->count[0];
        }
-}
 
-int printk_delay_msec __read_mostly;
+#ifdef CONFIG_PRINTK_NMI
+       if (in_nmi())
+               count++;
+#endif
+
+       return count;
+}
 
-static inline void printk_delay(void)
+static bool printk_enter_irqsave(unsigned long *flags)
 {
-       if (unlikely(printk_delay_msec)) {
-               int m = printk_delay_msec;
+       char *count;
 
-               while (m--) {
-                       mdelay(1);
-                       touch_nmi_watchdog();
-               }
+       local_irq_save(*flags);
+       count = printk_recursion_counter();
+       /* Only 1 level of recursion allowed. */
+       if (*count > 1) {
+               local_irq_restore(*flags);
+               return false;
        }
+       (*count)++;
+
+       return true;
+}
+
+static void printk_exit_irqrestore(unsigned long flags)
+{
+       char *count;
+
+       count = printk_recursion_counter();
+       (*count)--;
+       local_irq_restore(flags);
 }
 
 static inline u32 printk_caller_id(void)
@@ -1931,144 +1874,248 @@ static inline u32 printk_caller_id(void)
                0x80000000 + raw_smp_processor_id();
 }
 
-static size_t log_output(int facility, int level, enum log_flags lflags,
-                        const struct dev_printk_info *dev_info,
-                        char *text, size_t text_len)
+/**
+ * parse_prefix - Parse level and control flags.
+ *
+ * @text:     The terminated text message.
+ * @level:    A pointer to the current level value, will be updated.
+ * @lflags:   A pointer to the current log flags, will be updated.
+ *
+ * @level may be NULL if the caller is not interested in the parsed value.
+ * Otherwise the variable pointed to by @level must be set to
+ * LOGLEVEL_DEFAULT in order to be updated with the parsed value.
+ *
+ * @lflags may be NULL if the caller is not interested in the parsed value.
+ * Otherwise the variable pointed to by @lflags will be OR'd with the parsed
+ * value.
+ *
+ * Return: The length of the parsed level and control flags.
+ */
+static u16 parse_prefix(char *text, int *level, enum log_flags *lflags)
 {
-       const u32 caller_id = printk_caller_id();
+       u16 prefix_len = 0;
+       int kern_level;
 
-       if (lflags & LOG_CONT) {
-               struct prb_reserved_entry e;
-               struct printk_record r;
+       while (*text) {
+               kern_level = printk_get_level(text);
+               if (!kern_level)
+                       break;
 
-               prb_rec_init_wr(&r, text_len);
-               if (prb_reserve_in_last(&e, prb, &r, caller_id, LOG_LINE_MAX)) {
-                       memcpy(&r.text_buf[r.info->text_len], text, text_len);
-                       r.info->text_len += text_len;
-                       if (lflags & LOG_NEWLINE) {
-                               r.info->flags |= LOG_NEWLINE;
-                               prb_final_commit(&e);
-                       } else {
-                               prb_commit(&e);
-                       }
-                       return text_len;
+               switch (kern_level) {
+               case '0' ... '7':
+                       if (level && *level == LOGLEVEL_DEFAULT)
+                               *level = kern_level - '0';
+                       break;
+               case 'c':       /* KERN_CONT */
+                       if (lflags)
+                               *lflags |= LOG_CONT;
                }
+
+               prefix_len += 2;
+               text += 2;
        }
 
-       /* Store it in the record log */
-       return log_store(caller_id, facility, level, lflags, 0,
-                        dev_info, text, text_len);
+       return prefix_len;
 }
 
-/* Must be called under logbuf_lock. */
-int vprintk_store(int facility, int level,
-                 const struct dev_printk_info *dev_info,
-                 const char *fmt, va_list args)
+static u16 printk_sprint(char *text, u16 size, int facility, enum log_flags *lflags,
+                        const char *fmt, va_list args)
 {
-       static char textbuf[LOG_LINE_MAX];
-       char *text = textbuf;
-       size_t text_len;
-       enum log_flags lflags = 0;
+       u16 text_len;
 
-       /*
-        * The printf needs to come first; we need the syslog
-        * prefix which might be passed-in as a parameter.
-        */
-       text_len = vscnprintf(text, sizeof(textbuf), fmt, args);
+       text_len = vscnprintf(text, size, fmt, args);
 
-       /* mark and strip a trailing newline */
-       if (text_len && text[text_len-1] == '\n') {
+       /* Mark and strip a trailing newline. */
+       if (text_len && text[text_len - 1] == '\n') {
                text_len--;
-               lflags |= LOG_NEWLINE;
+               *lflags |= LOG_NEWLINE;
        }
 
-       /* strip kernel syslog prefix and extract log level or control flags */
+       /* Strip log level and control flags. */
        if (facility == 0) {
-               int kern_level;
-
-               while ((kern_level = printk_get_level(text)) != 0) {
-                       switch (kern_level) {
-                       case '0' ... '7':
-                               if (level == LOGLEVEL_DEFAULT)
-                                       level = kern_level - '0';
-                               break;
-                       case 'c':       /* KERN_CONT */
-                               lflags |= LOG_CONT;
-                       }
+               u16 prefix_len;
 
-                       text_len -= 2;
-                       text += 2;
+               prefix_len = parse_prefix(text, NULL, NULL);
+               if (prefix_len) {
+                       text_len -= prefix_len;
+                       memmove(text, text + prefix_len, text_len);
                }
        }
 
-       if (level == LOGLEVEL_DEFAULT)
-               level = default_message_loglevel;
-
-       if (dev_info)
-               lflags |= LOG_NEWLINE;
-
-       return log_output(facility, level, lflags, dev_info, text, text_len);
+       return text_len;
 }
 
-asmlinkage int vprintk_emit(int facility, int level,
-                           const struct dev_printk_info *dev_info,
-                           const char *fmt, va_list args)
+__printf(4, 0)
+static int vprintk_store(int facility, int level,
+                        const struct dev_printk_info *dev_info,
+                        const char *fmt, va_list args)
 {
-       int printed_len;
-       bool in_sched = false;
-       unsigned long flags;
-
-       /* Suppress unimportant messages after panic happens */
-       if (unlikely(suppress_printk))
+       const u32 caller_id = printk_caller_id();
+       struct prb_reserved_entry e;
+       enum log_flags lflags = 0;
+       bool final_commit = false;
+       struct printk_record r;
+       unsigned long irqflags;
+       u16 trunc_msg_len = 0;
+       char prefix_buf[8];
+       u16 reserve_size;
+       va_list args2;
+       u16 text_len;
+       int ret = 0;
+       u64 ts_nsec;
+       u64 seq;
+
+       /*
+        * Since the duration of printk() can vary depending on the message
+        * and state of the ringbuffer, grab the timestamp now so that it is
+        * close to the call of printk(). This provides a more deterministic
+        * timestamp with respect to the caller.
+        */
+       ts_nsec = local_clock();
+
+       if (!printk_enter_irqsave(&irqflags))
                return 0;
 
-       if (level == LOGLEVEL_SCHED) {
-               level = LOGLEVEL_DEFAULT;
-               in_sched = true;
+       /*
+        * The sprintf needs to come first since the syslog prefix might be
+        * passed in as a parameter. An extra byte must be reserved so that
+        * later the vscnprintf() into the reserved buffer has room for the
+        * terminating '\0', which is not counted by vsnprintf().
+        */
+       va_copy(args2, args);
+       reserve_size = vsnprintf(&prefix_buf[0], sizeof(prefix_buf), fmt, args2) + 1;
+       va_end(args2);
+
+       if (reserve_size > LOG_LINE_MAX)
+               reserve_size = LOG_LINE_MAX;
+
+       /* Extract log level or control flags. */
+       if (facility == 0)
+               parse_prefix(&prefix_buf[0], &level, &lflags);
+
+       if (level == LOGLEVEL_DEFAULT)
+               level = default_message_loglevel;
+
+       if (dev_info)
+               lflags |= LOG_NEWLINE;
+
+       if (lflags & LOG_CONT) {
+               prb_rec_init_wr(&r, reserve_size);
+               if (prb_reserve_in_last(&e, prb, &r, caller_id, LOG_LINE_MAX)) {
+                       seq = r.info->seq;
+                       text_len = printk_sprint(&r.text_buf[r.info->text_len], reserve_size,
+                                                facility, &lflags, fmt, args);
+                       r.info->text_len += text_len;
+
+                       if (lflags & LOG_NEWLINE) {
+                               r.info->flags |= LOG_NEWLINE;
+                               prb_final_commit(&e);
+                               final_commit = true;
+                       } else {
+                               prb_commit(&e);
+                       }
+
+                       ret = text_len;
+                       goto out;
+               }
        }
 
-       boot_delay_msec(level);
-       printk_delay();
+       /*
+        * Explicitly initialize the record before every prb_reserve() call.
+        * prb_reserve_in_last() and prb_reserve() purposely invalidate the
+        * structure when they fail.
+        */
+       prb_rec_init_wr(&r, reserve_size);
+       if (!prb_reserve(&e, prb, &r)) {
+               /* truncate the message if it is too long for empty buffer */
+               truncate_msg(&reserve_size, &trunc_msg_len);
 
-       /* This stops the holder of console_sem just where we want him */
-       logbuf_lock_irqsave(flags);
-       printed_len = vprintk_store(facility, level, dev_info, fmt, args);
-       logbuf_unlock_irqrestore(flags);
+               prb_rec_init_wr(&r, reserve_size + trunc_msg_len);
+               if (!prb_reserve(&e, prb, &r))
+                       goto out;
+       }
 
-       /* If called from the scheduler, we can not call up(). */
-       if (!in_sched) {
-               /*
-                * Disable preemption to avoid being preempted while holding
-                * console_sem which would prevent anyone from printing to
-                * console
-                */
-               preempt_disable();
-               /*
-                * 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_spinning())
-                       console_unlock();
-               preempt_enable();
+       seq = r.info->seq;
+
+       /* fill message */
+       text_len = printk_sprint(&r.text_buf[0], reserve_size, facility, &lflags, fmt, args);
+       if (trunc_msg_len)
+               memcpy(&r.text_buf[text_len], trunc_msg, trunc_msg_len);
+       r.info->text_len = text_len + trunc_msg_len;
+       r.info->facility = facility;
+       r.info->level = level & 7;
+       r.info->flags = lflags & 0x1f;
+       r.info->ts_nsec = ts_nsec;
+       r.info->caller_id = caller_id;
+       if (dev_info)
+               memcpy(&r.info->dev_info, dev_info, sizeof(r.info->dev_info));
+
+       /* A message without a trailing newline can be continued. */
+       if (!(lflags & LOG_NEWLINE)) {
+               prb_commit(&e);
+       } else {
+               prb_final_commit(&e);
+               final_commit = true;
        }
 
+       ret = text_len + trunc_msg_len;
+out:
+       /* only the kernel may perform synchronous printing */
+       if (facility == 0 && final_commit) {
+               struct console *con;
+
+               for_each_console(con) {
+                       if (console_can_sync(con))
+                               print_sync_until(con, seq + 1);
+               }
+       }
+
+       printk_exit_irqrestore(irqflags);
+       return ret;
+}
+
+asmlinkage int vprintk_emit(int facility, int level,
+                           const struct dev_printk_info *dev_info,
+                           const char *fmt, va_list args)
+{
+       int printed_len;
+
+       /* Suppress unimportant messages after panic happens */
+       if (unlikely(suppress_printk))
+               return 0;
+
+       if (level == LOGLEVEL_SCHED)
+               level = LOGLEVEL_DEFAULT;
+
+       printed_len = vprintk_store(facility, level, dev_info, fmt, args);
+
        wake_up_klogd();
        return printed_len;
 }
 EXPORT_SYMBOL(vprintk_emit);
 
-asmlinkage int vprintk(const char *fmt, va_list args)
+__printf(1, 0)
+static int vprintk_default(const char *fmt, va_list args)
 {
-       return vprintk_func(fmt, args);
+       return vprintk_emit(0, LOGLEVEL_DEFAULT, NULL, fmt, args);
 }
-EXPORT_SYMBOL(vprintk);
 
-int vprintk_default(const char *fmt, va_list args)
+__printf(1, 0)
+static int vprintk_func(const char *fmt, va_list args)
 {
-       return vprintk_emit(0, LOGLEVEL_DEFAULT, NULL, fmt, args);
+#ifdef CONFIG_KGDB_KDB
+       /* Allow to pass printk() to kdb but avoid a recursion. */
+       if (unlikely(kdb_trap_printk && kdb_printf_cpu < 0))
+               return vkdb_printf(KDB_MSGSRC_PRINTK, fmt, args);
+#endif
+       return vprintk_default(fmt, args);
+}
+
+asmlinkage int vprintk(const char *fmt, va_list args)
+{
+       return vprintk_func(fmt, args);
 }
-EXPORT_SYMBOL_GPL(vprintk_default);
+EXPORT_SYMBOL(vprintk);
 
 /**
  * printk - print a kernel message
@@ -2104,38 +2151,158 @@ asmlinkage __visible int printk(const char *fmt, ...)
 }
 EXPORT_SYMBOL(printk);
 
-#else /* CONFIG_PRINTK */
+static int printk_kthread_func(void *data)
+{
+       struct console *con = data;
+       unsigned long dropped = 0;
+       char *dropped_text = NULL;
+       struct printk_info info;
+       struct printk_record r;
+       char *ext_text = NULL;
+       size_t dropped_len;
+       int ret = -ENOMEM;
+       char *text = NULL;
+       char *write_text;
+       u64 printk_seq;
+       size_t len;
+       int error;
+       u64 seq;
 
-#define LOG_LINE_MAX           0
-#define PREFIX_MAX             0
-#define printk_time            false
+       if (con->flags & CON_EXTENDED) {
+               ext_text = kmalloc(CONSOLE_EXT_LOG_MAX, GFP_KERNEL);
+               if (!ext_text)
+                       goto out;
+       }
+       text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);
+       dropped_text = kmalloc(64, GFP_KERNEL);
+       if (!text || !dropped_text)
+               goto out;
 
-#define prb_read_valid(rb, seq, r)     false
-#define prb_first_valid_seq(rb)                0
+       if (con->flags & CON_EXTENDED)
+               write_text = ext_text;
+       else
+               write_text = text;
 
-static u64 syslog_seq;
-static u64 console_seq;
-static u64 exclusive_console_stop_seq;
-static unsigned long console_dropped;
+       seq = atomic64_read(&con->printk_seq);
+
+       prb_rec_init_rd(&r, &info, text, LOG_LINE_MAX + PREFIX_MAX);
+
+       for (;;) {
+               error = wait_event_interruptible(log_wait,
+                               prb_read_valid(prb, seq, &r) || kthread_should_stop());
 
-static size_t record_print_text(const struct printk_record *r,
-                               bool syslog, bool time)
+               if (kthread_should_stop())
+                       break;
+
+               if (error)
+                       continue;
+
+               if (seq != r.info->seq) {
+                       dropped += r.info->seq - seq;
+                       seq = r.info->seq;
+               }
+
+               seq++;
+
+               if (!(con->flags & CON_ENABLED))
+                       continue;
+
+               if (suppress_message_printing(r.info->level))
+                       continue;
+
+               if (con->flags & CON_EXTENDED) {
+                       len = info_print_ext_header(ext_text,
+                               CONSOLE_EXT_LOG_MAX,
+                               r.info);
+                       len += msg_print_ext_body(ext_text + len,
+                               CONSOLE_EXT_LOG_MAX - len,
+                               &r.text_buf[0], r.info->text_len,
+                               &r.info->dev_info);
+               } else {
+                       len = record_print_text(&r,
+                               console_msg_format & MSG_FORMAT_SYSLOG,
+                               printk_time);
+               }
+
+               printk_seq = atomic64_read(&con->printk_seq);
+
+               console_lock();
+               console_may_schedule = 0;
+
+               if (kernel_sync_mode() && con->write_atomic) {
+                       console_unlock();
+                       break;
+               }
+
+               if (!(con->flags & CON_EXTENDED) && dropped) {
+                       dropped_len = snprintf(dropped_text, 64,
+                                              "** %lu printk messages dropped **\n",
+                                              dropped);
+                       dropped = 0;
+
+                       con->write(con, dropped_text, dropped_len);
+                       printk_delay(r.info->level);
+               }
+
+               con->write(con, write_text, len);
+               if (len)
+                       printk_delay(r.info->level);
+
+               atomic64_cmpxchg_relaxed(&con->printk_seq, printk_seq, seq);
+
+               console_unlock();
+       }
+out:
+       kfree(dropped_text);
+       kfree(text);
+       kfree(ext_text);
+       pr_info("%sconsole [%s%d]: printing thread stopped\n",
+               (con->flags & CON_BOOT) ? "boot" : "",
+               con->name, con->index);
+       return ret;
+}
+
+/* Must be called within console_lock(). */
+static void start_printk_kthread(struct console *con)
 {
-       return 0;
+       con->thread = kthread_run(printk_kthread_func, con,
+                                 "pr/%s%d", con->name, con->index);
+       if (IS_ERR(con->thread)) {
+               pr_err("%sconsole [%s%d]: unable to start printing thread\n",
+                       (con->flags & CON_BOOT) ? "boot" : "",
+                       con->name, con->index);
+               return;
+       }
+       pr_info("%sconsole [%s%d]: printing thread started\n",
+               (con->flags & CON_BOOT) ? "boot" : "",
+               con->name, con->index);
 }
-static ssize_t info_print_ext_header(char *buf, size_t size,
-                                    struct printk_info *info)
+
+/* protected by console_lock */
+static bool kthreads_started;
+
+/* Must be called within console_lock(). */
+static void console_try_thread(struct console *con)
 {
-       return 0;
+       if (kthreads_started) {
+               start_printk_kthread(con);
+               return;
+       }
+
+       /*
+        * The printing threads have not been started yet. If this console
+        * can print synchronously, print all unprinted messages.
+        */
+       if (console_can_sync(con))
+               print_sync_until(con, prb_next_seq(prb));
 }
-static ssize_t msg_print_ext_body(char *buf, size_t size,
-                                 char *text, size_t text_len,
-                                 struct dev_printk_info *dev_info) { return 0; }
-static void console_lock_spinning_enable(void) { }
-static int console_lock_spinning_disable_and_check(void) { return 0; }
-static void call_console_drivers(const char *ext_text, size_t ext_len,
-                                const char *text, size_t len) {}
-static bool suppress_message_printing(int level) { return false; }
+
+#else /* CONFIG_PRINTK */
+
+#define prb_first_valid_seq(rb)                0
+#define prb_next_seq(rb)               0
+
+#define console_try_thread(con)
 
 #endif /* CONFIG_PRINTK */
 
@@ -2380,34 +2547,6 @@ int is_console_locked(void)
 }
 EXPORT_SYMBOL(is_console_locked);
 
-/*
- * Check if we have any console that is capable of printing while cpu is
- * booting or shutting down. Requires console_sem.
- */
-static int have_callable_console(void)
-{
-       struct console *con;
-
-       for_each_console(con)
-               if ((con->flags & CON_ENABLED) &&
-                               (con->flags & CON_ANYTIME))
-                       return 1;
-
-       return 0;
-}
-
-/*
- * Can we actually use the console at this time on this cpu?
- *
- * Console drivers may assume that per-cpu resources have been allocated. So
- * unless they're explicitly marked as being able to cope (CON_ANYTIME) don't
- * call them until this CPU is officially up.
- */
-static inline int can_use_console(void)
-{
-       return cpu_online(raw_smp_processor_id()) || have_callable_console();
-}
-
 /**
  * console_unlock - unlock the console system
  *
@@ -2424,142 +2563,14 @@ static inline int can_use_console(void)
  */
 void console_unlock(void)
 {
-       static char ext_text[CONSOLE_EXT_LOG_MAX];
-       static char text[LOG_LINE_MAX + PREFIX_MAX];
-       unsigned long flags;
-       bool do_cond_resched, retry;
-       struct printk_info info;
-       struct printk_record r;
-
        if (console_suspended) {
                up_console_sem();
                return;
        }
 
-       prb_rec_init_rd(&r, &info, text, sizeof(text));
-
-       /*
-        * Console drivers are called with interrupts disabled, so
-        * @console_may_schedule should be cleared before; however, we may
-        * end up dumping a lot of lines, for example, if called from
-        * console registration path, and should invoke cond_resched()
-        * between lines if allowable.  Not doing so can cause a very long
-        * scheduling stall on a slow console leading to RCU stall and
-        * softlockup warnings which exacerbate the issue with more
-        * messages practically incapacitating the system.
-        *
-        * console_trylock() is not able to detect the preemptive
-        * context reliably. Therefore the value must be stored before
-        * and cleared after the "again" goto label.
-        */
-       do_cond_resched = console_may_schedule;
-again:
-       console_may_schedule = 0;
-
-       /*
-        * We released the console_sem lock, so we need to recheck if
-        * cpu is online and (if not) is there at least one CON_ANYTIME
-        * console.
-        */
-       if (!can_use_console()) {
-               console_locked = 0;
-               up_console_sem();
-               return;
-       }
-
-       for (;;) {
-               size_t ext_len = 0;
-               size_t len;
-
-               printk_safe_enter_irqsave(flags);
-               raw_spin_lock(&logbuf_lock);
-skip:
-               if (!prb_read_valid(prb, console_seq, &r))
-                       break;
-
-               if (console_seq != r.info->seq) {
-                       console_dropped += r.info->seq - console_seq;
-                       console_seq = r.info->seq;
-               }
-
-               if (suppress_message_printing(r.info->level)) {
-                       /*
-                        * Skip record we have buffered and already printed
-                        * directly to the console when we received it, and
-                        * record that has level above the console loglevel.
-                        */
-                       console_seq++;
-                       goto skip;
-               }
-
-               /* Output to all consoles once old messages replayed. */
-               if (unlikely(exclusive_console &&
-                            console_seq >= exclusive_console_stop_seq)) {
-                       exclusive_console = NULL;
-               }
-
-               /*
-                * Handle extended console text first because later
-                * record_print_text() will modify the record buffer in-place.
-                */
-               if (nr_ext_console_drivers) {
-                       ext_len = info_print_ext_header(ext_text,
-                                               sizeof(ext_text),
-                                               r.info);
-                       ext_len += msg_print_ext_body(ext_text + ext_len,
-                                               sizeof(ext_text) - ext_len,
-                                               &r.text_buf[0],
-                                               r.info->text_len,
-                                               &r.info->dev_info);
-               }
-               len = record_print_text(&r,
-                               console_msg_format & MSG_FORMAT_SYSLOG,
-                               printk_time);
-               console_seq++;
-               raw_spin_unlock(&logbuf_lock);
-
-               /*
-                * While actively printing out messages, if another printk()
-                * were to occur on another CPU, it may wait for this one to
-                * finish. This task can not be preempted if there is a
-                * waiter waiting to take over.
-                */
-               console_lock_spinning_enable();
-
-               stop_critical_timings();        /* don't trace print latency */
-               call_console_drivers(ext_text, ext_len, text, len);
-               start_critical_timings();
-
-               if (console_lock_spinning_disable_and_check()) {
-                       printk_safe_exit_irqrestore(flags);
-                       return;
-               }
-
-               printk_safe_exit_irqrestore(flags);
-
-               if (do_cond_resched)
-                       cond_resched();
-       }
-
        console_locked = 0;
 
-       raw_spin_unlock(&logbuf_lock);
-
        up_console_sem();
-
-       /*
-        * Someone could have filled up the buffer again, so re-check if there's
-        * something to flush. In case we cannot trylock the console_sem again,
-        * there's a new owner and the console_unlock() from them will do the
-        * flush, no worries.
-        */
-       raw_spin_lock(&logbuf_lock);
-       retry = prb_read_valid(prb, console_seq, NULL);
-       raw_spin_unlock(&logbuf_lock);
-       printk_safe_exit_irqrestore(flags);
-
-       if (retry && console_trylock())
-               goto again;
 }
 EXPORT_SYMBOL(console_unlock);
 
@@ -2609,23 +2620,20 @@ void console_unblank(void)
  */
 void console_flush_on_panic(enum con_flush_mode mode)
 {
-       /*
-        * If someone else is holding the console lock, trylock will fail
-        * and may_schedule may be set.  Ignore and proceed to unlock so
-        * that messages are flushed out.  As this can be called from any
-        * context and we don't want to get preempted while flushing,
-        * ensure may_schedule is cleared.
-        */
-       console_trylock();
+       struct console *c;
+       u64 seq;
+
+       if (!console_trylock())
+               return;
+
        console_may_schedule = 0;
 
        if (mode == CONSOLE_REPLAY_ALL) {
-               unsigned long flags;
-
-               logbuf_lock_irqsave(flags);
-               console_seq = prb_first_valid_seq(prb);
-               logbuf_unlock_irqrestore(flags);
+               seq = prb_first_valid_seq(prb);
+               for_each_console(c)
+                       atomic64_set(&c->printk_seq, seq);
        }
+
        console_unlock();
 }
 
@@ -2760,7 +2768,6 @@ static int try_enable_new_console(struct console *newcon, bool user_specified)
  */
 void register_console(struct console *newcon)
 {
-       unsigned long flags;
        struct console *bcon = NULL;
        int err;
 
@@ -2784,6 +2791,8 @@ void register_console(struct console *newcon)
                }
        }
 
+       newcon->thread = NULL;
+
        if (console_drivers && console_drivers->flags & CON_BOOT)
                bcon = console_drivers;
 
@@ -2825,8 +2834,10 @@ void register_console(struct console *newcon)
         * the real console are the same physical device, it's annoying to
         * see the beginning boot messages twice
         */
-       if (bcon && ((newcon->flags & (CON_CONSDEV | CON_BOOT)) == CON_CONSDEV))
+       if (bcon && ((newcon->flags & (CON_CONSDEV | CON_BOOT)) == CON_CONSDEV)) {
                newcon->flags &= ~CON_PRINTBUFFER;
+               newcon->flags |= CON_HANDOVER;
+       }
 
        /*
         *      Put this console in the list - keep the
@@ -2848,26 +2859,12 @@ void register_console(struct console *newcon)
        if (newcon->flags & CON_EXTENDED)
                nr_ext_console_drivers++;
 
-       if (newcon->flags & CON_PRINTBUFFER) {
-               /*
-                * console_unlock(); will print out the buffered messages
-                * for us.
-                */
-               logbuf_lock_irqsave(flags);
-               /*
-                * We're about to replay the log buffer.  Only do this to the
-                * just-registered console to avoid excessive message spam to
-                * the already-registered consoles.
-                *
-                * Set exclusive_console with disabled interrupts to reduce
-                * race window with eventual console_flush_on_panic() that
-                * ignores console_lock.
-                */
-               exclusive_console = newcon;
-               exclusive_console_stop_seq = console_seq;
-               console_seq = syslog_seq;
-               logbuf_unlock_irqrestore(flags);
-       }
+       if (newcon->flags & CON_PRINTBUFFER)
+               atomic64_set(&newcon->printk_seq, 0);
+       else
+               atomic64_set(&newcon->printk_seq, prb_next_seq(prb));
+
+       console_try_thread(newcon);
        console_unlock();
        console_sysfs_notify();
 
@@ -2941,6 +2938,9 @@ int unregister_console(struct console *console)
        console_unlock();
        console_sysfs_notify();
 
+       if (console->thread && !IS_ERR(console->thread))
+               kthread_stop(console->thread);
+
        if (console->exit)
                res = console->exit(console);
 
@@ -3023,6 +3023,15 @@ static int __init printk_late_init(void)
                        unregister_console(con);
                }
        }
+
+#ifdef CONFIG_PRINTK
+       console_lock();
+       for_each_console(con)
+               start_printk_kthread(con);
+       kthreads_started = true;
+       console_unlock();
+#endif
+
        ret = cpuhp_setup_state_nocalls(CPUHP_PRINTK_DEAD, "printk:dead", NULL,
                                        console_cpu_notify);
        WARN_ON(ret < 0);
@@ -3038,7 +3047,6 @@ late_initcall(printk_late_init);
  * Delayed printk version, for scheduler-internal messages:
  */
 #define PRINTK_PENDING_WAKEUP  0x01
-#define PRINTK_PENDING_OUTPUT  0x02
 
 static DEFINE_PER_CPU(int, printk_pending);
 
@@ -3046,14 +3054,8 @@ static void wake_up_klogd_work_func(struct irq_work *irq_work)
 {
        int pending = __this_cpu_xchg(printk_pending, 0);
 
-       if (pending & PRINTK_PENDING_OUTPUT) {
-               /* If trylock fails, someone else is doing the printing */
-               if (console_trylock())
-                       console_unlock();
-       }
-
        if (pending & PRINTK_PENDING_WAKEUP)
-               wake_up_interruptible(&log_wait);
+               wake_up_interruptible_all(&log_wait);
 }
 
 static DEFINE_PER_CPU(struct irq_work, wake_up_klogd_work) = {
@@ -3074,25 +3076,10 @@ void wake_up_klogd(void)
        preempt_enable();
 }
 
-void defer_console_output(void)
-{
-       if (!printk_percpu_data_ready())
-               return;
-
-       preempt_disable();
-       __this_cpu_or(printk_pending, PRINTK_PENDING_OUTPUT);
-       irq_work_queue(this_cpu_ptr(&wake_up_klogd_work));
-       preempt_enable();
-}
-
-int vprintk_deferred(const char *fmt, va_list args)
+__printf(1, 0)
+static int vprintk_deferred(const char *fmt, va_list args)
 {
-       int r;
-
-       r = vprintk_emit(0, LOGLEVEL_SCHED, NULL, fmt, args);
-       defer_console_output();
-
-       return r;
+       return vprintk_emit(0, LOGLEVEL_DEFAULT, NULL, fmt, args);
 }
 
 int printk_deferred(const char *fmt, ...)
@@ -3231,8 +3218,26 @@ EXPORT_SYMBOL_GPL(kmsg_dump_reason_str);
  */
 void kmsg_dump(enum kmsg_dump_reason reason)
 {
+       struct kmsg_dumper_iter iter;
        struct kmsg_dumper *dumper;
-       unsigned long flags;
+
+       if (!oops_in_progress) {
+               /*
+                * If atomic consoles are available, activate kernel sync mode
+                * to make sure any final messages are visible. The trailing
+                * printk message is important to flush any pending messages.
+                */
+               if (have_atomic_console()) {
+                       sync_mode = true;
+                       pr_info("enabled sync mode\n");
+               }
+
+               /*
+                * Give the printing threads time to flush, allowing up to
+                * 1s of no printing forward progress before giving up.
+                */
+               pr_flush(1000, true);
+       }
 
        rcu_read_lock();
        list_for_each_entry_rcu(dumper, &dump_list, list) {
@@ -3250,25 +3255,18 @@ void kmsg_dump(enum kmsg_dump_reason reason)
                        continue;
 
                /* initialize iterator with data about the stored records */
-               dumper->active = true;
-
-               logbuf_lock_irqsave(flags);
-               dumper->cur_seq = clear_seq;
-               dumper->next_seq = prb_next_seq(prb);
-               logbuf_unlock_irqrestore(flags);
+               iter.active = true;
+               kmsg_dump_rewind(&iter);
 
                /* invoke dumper which will iterate over records */
-               dumper->dump(dumper, reason);
-
-               /* reset iterator */
-               dumper->active = false;
+               dumper->dump(dumper, reason, &iter);
        }
        rcu_read_unlock();
 }
 
 /**
- * kmsg_dump_get_line_nolock - retrieve one kmsg log line (unlocked version)
- * @dumper: registered kmsg dumper
+ * kmsg_dump_get_line - retrieve one kmsg log line
+ * @iter: kmsg dumper iterator
  * @syslog: include the "<4>" prefixes
  * @line: buffer to copy the line to
  * @size: maximum size of the buffer
@@ -3282,11 +3280,9 @@ void kmsg_dump(enum kmsg_dump_reason reason)
  *
  * A return value of FALSE indicates that there are no more records to
  * read.
- *
- * The function is similar to kmsg_dump_get_line(), but grabs no locks.
  */
-bool kmsg_dump_get_line_nolock(struct kmsg_dumper *dumper, bool syslog,
-                              char *line, size_t size, size_t *len)
+bool kmsg_dump_get_line(struct kmsg_dumper_iter *iter, bool syslog,
+                       char *line, size_t size, size_t *len)
 {
        struct printk_info info;
        unsigned int line_count;
@@ -3296,16 +3292,16 @@ bool kmsg_dump_get_line_nolock(struct kmsg_dumper *dumper, bool syslog,
 
        prb_rec_init_rd(&r, &info, line, size);
 
-       if (!dumper->active)
+       if (!iter->active)
                goto out;
 
        /* Read text or count text lines? */
        if (line) {
-               if (!prb_read_valid(prb, dumper->cur_seq, &r))
+               if (!prb_read_valid(prb, iter->cur_seq, &r))
                        goto out;
                l = record_print_text(&r, syslog, printk_time);
        } else {
-               if (!prb_read_valid_info(prb, dumper->cur_seq,
+               if (!prb_read_valid_info(prb, iter->cur_seq,
                                         &info, &line_count)) {
                        goto out;
                }
@@ -3314,48 +3310,18 @@ bool kmsg_dump_get_line_nolock(struct kmsg_dumper *dumper, bool syslog,
 
        }
 
-       dumper->cur_seq = r.info->seq + 1;
+       iter->cur_seq = r.info->seq + 1;
        ret = true;
 out:
        if (len)
                *len = l;
        return ret;
 }
-
-/**
- * kmsg_dump_get_line - retrieve one kmsg log line
- * @dumper: registered kmsg dumper
- * @syslog: include the "<4>" prefixes
- * @line: buffer to copy the line to
- * @size: maximum size of the buffer
- * @len: length of line placed into buffer
- *
- * Start at the beginning of the kmsg buffer, with the oldest kmsg
- * record, and copy one record into the provided buffer.
- *
- * Consecutive calls will return the next available record moving
- * towards the end of the buffer with the youngest messages.
- *
- * A return value of FALSE indicates that there are no more records to
- * read.
- */
-bool kmsg_dump_get_line(struct kmsg_dumper *dumper, bool syslog,
-                       char *line, size_t size, size_t *len)
-{
-       unsigned long flags;
-       bool ret;
-
-       logbuf_lock_irqsave(flags);
-       ret = kmsg_dump_get_line_nolock(dumper, syslog, line, size, len);
-       logbuf_unlock_irqrestore(flags);
-
-       return ret;
-}
 EXPORT_SYMBOL_GPL(kmsg_dump_get_line);
 
 /**
  * kmsg_dump_get_buffer - copy kmsg log lines
- * @dumper: registered kmsg dumper
+ * @iter: kmsg dumper iterator
  * @syslog: include the "<4>" prefixes
  * @buf: buffer to copy the line to
  * @size: maximum size of the buffer
@@ -3372,116 +3338,256 @@ EXPORT_SYMBOL_GPL(kmsg_dump_get_line);
  * A return value of FALSE indicates that there are no more records to
  * read.
  */
-bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog,
-                         char *buf, size_t size, size_t *len)
+bool kmsg_dump_get_buffer(struct kmsg_dumper_iter *iter, bool syslog,
+                         char *buf, size_t size, size_t *len_out)
 {
        struct printk_info info;
-       unsigned int line_count;
        struct printk_record r;
-       unsigned long flags;
        u64 seq;
        u64 next_seq;
-       size_t l = 0;
+       size_t len = 0;
        bool ret = false;
        bool time = printk_time;
 
-       prb_rec_init_rd(&r, &info, buf, size);
-
-       if (!dumper->active || !buf || !size)
+       if (!iter->active || !buf || !size)
                goto out;
 
-       logbuf_lock_irqsave(flags);
-       if (prb_read_valid_info(prb, dumper->cur_seq, &info, NULL)) {
-               if (info.seq != dumper->cur_seq) {
+       if (prb_read_valid_info(prb, iter->cur_seq, &info, NULL)) {
+               if (info.seq != iter->cur_seq) {
                        /* messages are gone, move to first available one */
-                       dumper->cur_seq = info.seq;
+                       iter->cur_seq = info.seq;
                }
        }
 
        /* last entry */
-       if (dumper->cur_seq >= dumper->next_seq) {
-               logbuf_unlock_irqrestore(flags);
+       if (iter->cur_seq >= iter->next_seq)
                goto out;
-       }
-
-       /* calculate length of entire buffer */
-       seq = dumper->cur_seq;
-       while (prb_read_valid_info(prb, seq, &info, &line_count)) {
-               if (r.info->seq >= dumper->next_seq)
-                       break;
-               l += get_record_print_text_size(&info, line_count, syslog, time);
-               seq = r.info->seq + 1;
-       }
 
-       /* move first record forward until length fits into the buffer */
-       seq = dumper->cur_seq;
-       while (l >= size && prb_read_valid_info(prb, seq,
-                                               &info, &line_count)) {
-               if (r.info->seq >= dumper->next_seq)
-                       break;
-               l -= get_record_print_text_size(&info, line_count, syslog, time);
-               seq = r.info->seq + 1;
-       }
+       /*
+        * Find first record that fits, including all following records,
+        * into the user-provided buffer for this dump. Pass in size-1
+        * because this function (by way of record_print_text()) will
+        * not write more than size-1 bytes of text into @buf.
+        */
+       seq = find_first_fitting_seq(iter->cur_seq, iter->next_seq,
+                                    size - 1, syslog, time);
 
-       /* last message in next interation */
+       /*
+        * Next kmsg_dump_get_buffer() invocation will dump block of
+        * older records stored right before this one.
+        */
        next_seq = seq;
 
-       /* actually read text into the buffer now */
-       l = 0;
-       while (prb_read_valid(prb, seq, &r)) {
-               if (r.info->seq >= dumper->next_seq)
-                       break;
+       prb_rec_init_rd(&r, &info, buf, size);
 
-               l += record_print_text(&r, syslog, time);
+       len = 0;
+       prb_for_each_record(seq, prb, seq, &r) {
+               if (r.info->seq >= iter->next_seq)
+                       break;
 
-               /* adjust record to store to remaining buffer space */
-               prb_rec_init_rd(&r, &info, buf + l, size - l);
+               len += record_print_text(&r, syslog, time);
 
-               seq = r.info->seq + 1;
+               /* Adjust record to store to remaining buffer space. */
+               prb_rec_init_rd(&r, &info, buf + len, size - len);
        }
 
-       dumper->next_seq = next_seq;
+       iter->next_seq = next_seq;
        ret = true;
-       logbuf_unlock_irqrestore(flags);
 out:
-       if (len)
-               *len = l;
+       if (len_out)
+               *len_out = len;
        return ret;
 }
 EXPORT_SYMBOL_GPL(kmsg_dump_get_buffer);
 
 /**
- * kmsg_dump_rewind_nolock - reset the iterator (unlocked version)
- * @dumper: registered kmsg dumper
+ * kmsg_dump_rewind - reset the iterator
+ * @iter: kmsg dumper iterator
  *
  * Reset the dumper's iterator so that kmsg_dump_get_line() and
  * kmsg_dump_get_buffer() can be called again and used multiple
  * times within the same dumper.dump() callback.
+ */
+void kmsg_dump_rewind(struct kmsg_dumper_iter *iter)
+{
+       iter->cur_seq = latched_seq_read_nolock(&clear_seq);
+       iter->next_seq = prb_next_seq(prb);
+}
+EXPORT_SYMBOL_GPL(kmsg_dump_rewind);
+
+#endif
+
+struct prb_cpulock {
+       atomic_t owner;
+       unsigned long __percpu *irqflags;
+};
+
+#define DECLARE_STATIC_PRINTKRB_CPULOCK(name)                          \
+static DEFINE_PER_CPU(unsigned long, _##name##_percpu_irqflags);       \
+static struct prb_cpulock name = {                                     \
+       .owner = ATOMIC_INIT(-1),                                       \
+       .irqflags = &_##name##_percpu_irqflags,                         \
+}
+
+static bool __prb_trylock(struct prb_cpulock *cpu_lock,
+                         unsigned int *cpu_store)
+{
+       unsigned long *flags;
+       unsigned int cpu;
+
+       cpu = get_cpu();
+
+       *cpu_store = atomic_read(&cpu_lock->owner);
+       /* memory barrier to ensure the current lock owner is visible */
+       smp_rmb();
+       if (*cpu_store == -1) {
+               flags = per_cpu_ptr(cpu_lock->irqflags, cpu);
+               local_irq_save(*flags);
+               if (atomic_try_cmpxchg_acquire(&cpu_lock->owner,
+                                              cpu_store, cpu)) {
+                       return true;
+               }
+               local_irq_restore(*flags);
+       } else if (*cpu_store == cpu) {
+               return true;
+       }
+
+       put_cpu();
+       return false;
+}
+
+/*
+ * prb_lock: Perform a processor-reentrant spin lock.
+ * @cpu_lock: A pointer to the lock object.
+ * @cpu_store: A "flags" pointer to store lock status information.
+ *
+ * If no processor has the lock, the calling processor takes the lock and
+ * becomes the owner. If the calling processor is already the owner of the
+ * lock, this function succeeds immediately. If lock is locked by another
+ * processor, this function spins until the calling processor becomes the
+ * owner.
+ *
+ * It is safe to call this function from any context and state.
+ */
+static void prb_lock(struct prb_cpulock *cpu_lock, unsigned int *cpu_store)
+{
+       for (;;) {
+               if (__prb_trylock(cpu_lock, cpu_store))
+                       break;
+               cpu_relax();
+       }
+}
+
+/*
+ * prb_unlock: Perform a processor-reentrant spin unlock.
+ * @cpu_lock: A pointer to the lock object.
+ * @cpu_store: A "flags" object storing lock status information.
  *
- * The function is similar to kmsg_dump_rewind(), but grabs no locks.
+ * Release the lock. The calling processor must be the owner of the lock.
+ *
+ * It is safe to call this function from any context and state.
  */
-void kmsg_dump_rewind_nolock(struct kmsg_dumper *dumper)
+static void prb_unlock(struct prb_cpulock *cpu_lock, unsigned int cpu_store)
 {
-       dumper->cur_seq = clear_seq;
-       dumper->next_seq = prb_next_seq(prb);
+       unsigned long *flags;
+       unsigned int cpu;
+
+       cpu = atomic_read(&cpu_lock->owner);
+       atomic_set_release(&cpu_lock->owner, cpu_store);
+
+       if (cpu_store == -1) {
+               flags = per_cpu_ptr(cpu_lock->irqflags, cpu);
+               local_irq_restore(*flags);
+       }
+
+       put_cpu();
+}
+
+DECLARE_STATIC_PRINTKRB_CPULOCK(printk_cpulock);
+
+void console_atomic_lock(unsigned int *flags)
+{
+       prb_lock(&printk_cpulock, flags);
+}
+EXPORT_SYMBOL(console_atomic_lock);
+
+void console_atomic_unlock(unsigned int flags)
+{
+       prb_unlock(&printk_cpulock, flags);
+}
+EXPORT_SYMBOL(console_atomic_unlock);
+
+static void pr_msleep(bool may_sleep, int ms)
+{
+       if (may_sleep) {
+               msleep(ms);
+       } else {
+               while (ms--)
+                       udelay(1000);
+       }
 }
 
 /**
- * kmsg_dump_rewind - reset the iterator
- * @dumper: registered kmsg dumper
+ * pr_flush() - Wait for printing threads to catch up.
  *
- * Reset the dumper's iterator so that kmsg_dump_get_line() and
- * kmsg_dump_get_buffer() can be called again and used multiple
- * times within the same dumper.dump() callback.
+ * @timeout_ms:        The maximum time (in ms) to wait.
+ * @reset_on_progress: Reset the timeout if forward progress is seen.
+ *
+ * A value of 0 for @timeout_ms means no waiting will occur. A value of -1
+ * represents infinite waiting.
+ *
+ * If @reset_on_progress is true, the timeout will be reset whenever any
+ * printer has been seen to make some forward progress.
+ *
+ * Context: Any context.
+ * Return: true if all enabled printers are caught up.
  */
-void kmsg_dump_rewind(struct kmsg_dumper *dumper)
+bool pr_flush(int timeout_ms, bool reset_on_progress)
 {
-       unsigned long flags;
+       int remaining = timeout_ms;
+       struct console *con;
+       u64 last_diff = 0;
+       bool may_sleep;
+       u64 printk_seq;
+       u64 diff;
+       u64 seq;
 
-       logbuf_lock_irqsave(flags);
-       kmsg_dump_rewind_nolock(dumper);
-       logbuf_unlock_irqrestore(flags);
-}
-EXPORT_SYMBOL_GPL(kmsg_dump_rewind);
+       may_sleep = (preemptible() &&
+                    !in_softirq() &&
+                    system_state >= SYSTEM_RUNNING);
 
-#endif
+       seq = prb_next_seq(prb);
+
+       for (;;) {
+               diff = 0;
+
+               for_each_console(con) {
+                       if (!(con->flags & CON_ENABLED))
+                               continue;
+                       printk_seq = atomic64_read(&con->printk_seq);
+                       if (printk_seq < seq)
+                               diff += seq - printk_seq;
+               }
+
+               if (diff != last_diff && reset_on_progress)
+                       remaining = timeout_ms;
+
+               if (!diff || remaining == 0)
+                       break;
+
+               if (remaining < 0) {
+                       pr_msleep(may_sleep, 100);
+               } else if (remaining < 100) {
+                       pr_msleep(may_sleep, remaining);
+                       remaining = 0;
+               } else {
+                       pr_msleep(may_sleep, 100);
+                       remaining -= 100;
+               }
+
+               last_diff = diff;
+       }
+
+       return (diff == 0);
+}
+EXPORT_SYMBOL(pr_flush);
diff --git a/kernel/printk/printk_safe.c b/kernel/printk/printk_safe.c
deleted file mode 100644 (file)
index 2e9e3ed..0000000
+++ /dev/null
@@ -1,422 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * printk_safe.c - Safe printk for printk-deadlock-prone contexts
- */
-
-#include <linux/preempt.h>
-#include <linux/spinlock.h>
-#include <linux/debug_locks.h>
-#include <linux/kdb.h>
-#include <linux/smp.h>
-#include <linux/cpumask.h>
-#include <linux/irq_work.h>
-#include <linux/printk.h>
-#include <linux/kprobes.h>
-
-#include "internal.h"
-
-/*
- * printk() could not take logbuf_lock in NMI context. Instead,
- * it uses an alternative implementation that temporary stores
- * the strings into a per-CPU buffer. The content of the buffer
- * is later flushed into the main ring buffer via IRQ work.
- *
- * The alternative implementation is chosen transparently
- * by examining current printk() context mask stored in @printk_context
- * per-CPU variable.
- *
- * The implementation allows to flush the strings also from another CPU.
- * There are situations when we want to make sure that all buffers
- * were handled or when IRQs are blocked.
- */
-
-#define SAFE_LOG_BUF_LEN ((1 << CONFIG_PRINTK_SAFE_LOG_BUF_SHIFT) -    \
-                               sizeof(atomic_t) -                      \
-                               sizeof(atomic_t) -                      \
-                               sizeof(struct irq_work))
-
-struct printk_safe_seq_buf {
-       atomic_t                len;    /* length of written data */
-       atomic_t                message_lost;
-       struct irq_work         work;   /* IRQ work that flushes the buffer */
-       unsigned char           buffer[SAFE_LOG_BUF_LEN];
-};
-
-static DEFINE_PER_CPU(struct printk_safe_seq_buf, safe_print_seq);
-static DEFINE_PER_CPU(int, printk_context);
-
-static DEFINE_RAW_SPINLOCK(safe_read_lock);
-
-#ifdef CONFIG_PRINTK_NMI
-static DEFINE_PER_CPU(struct printk_safe_seq_buf, nmi_print_seq);
-#endif
-
-/* Get flushed in a more safe context. */
-static void queue_flush_work(struct printk_safe_seq_buf *s)
-{
-       if (printk_percpu_data_ready())
-               irq_work_queue(&s->work);
-}
-
-/*
- * Add a message to per-CPU context-dependent buffer. NMI and printk-safe
- * have dedicated buffers, because otherwise printk-safe preempted by
- * NMI-printk would have overwritten the NMI messages.
- *
- * The messages are flushed from irq work (or from panic()), possibly,
- * from other CPU, concurrently with printk_safe_log_store(). Should this
- * happen, printk_safe_log_store() will notice the buffer->len mismatch
- * and repeat the write.
- */
-static __printf(2, 0) int printk_safe_log_store(struct printk_safe_seq_buf *s,
-                                               const char *fmt, va_list args)
-{
-       int add;
-       size_t len;
-       va_list ap;
-
-again:
-       len = atomic_read(&s->len);
-
-       /* The trailing '\0' is not counted into len. */
-       if (len >= sizeof(s->buffer) - 1) {
-               atomic_inc(&s->message_lost);
-               queue_flush_work(s);
-               return 0;
-       }
-
-       /*
-        * Make sure that all old data have been read before the buffer
-        * was reset. This is not needed when we just append data.
-        */
-       if (!len)
-               smp_rmb();
-
-       va_copy(ap, args);
-       add = vscnprintf(s->buffer + len, sizeof(s->buffer) - len, fmt, ap);
-       va_end(ap);
-       if (!add)
-               return 0;
-
-       /*
-        * Do it once again if the buffer has been flushed in the meantime.
-        * Note that atomic_cmpxchg() is an implicit memory barrier that
-        * makes sure that the data were written before updating s->len.
-        */
-       if (atomic_cmpxchg(&s->len, len, len + add) != len)
-               goto again;
-
-       queue_flush_work(s);
-       return add;
-}
-
-static inline void printk_safe_flush_line(const char *text, int len)
-{
-       /*
-        * Avoid any console drivers calls from here, because we may be
-        * in NMI or printk_safe context (when in panic). The messages
-        * must go only into the ring buffer at this stage.  Consoles will
-        * get explicitly called later when a crashdump is not generated.
-        */
-       printk_deferred("%.*s", len, text);
-}
-
-/* printk part of the temporary buffer line by line */
-static int printk_safe_flush_buffer(const char *start, size_t len)
-{
-       const char *c, *end;
-       bool header;
-
-       c = start;
-       end = start + len;
-       header = true;
-
-       /* Print line by line. */
-       while (c < end) {
-               if (*c == '\n') {
-                       printk_safe_flush_line(start, c - start + 1);
-                       start = ++c;
-                       header = true;
-                       continue;
-               }
-
-               /* Handle continuous lines or missing new line. */
-               if ((c + 1 < end) && printk_get_level(c)) {
-                       if (header) {
-                               c = printk_skip_level(c);
-                               continue;
-                       }
-
-                       printk_safe_flush_line(start, c - start);
-                       start = c++;
-                       header = true;
-                       continue;
-               }
-
-               header = false;
-               c++;
-       }
-
-       /* Check if there was a partial line. Ignore pure header. */
-       if (start < end && !header) {
-               static const char newline[] = KERN_CONT "\n";
-
-               printk_safe_flush_line(start, end - start);
-               printk_safe_flush_line(newline, strlen(newline));
-       }
-
-       return len;
-}
-
-static void report_message_lost(struct printk_safe_seq_buf *s)
-{
-       int lost = atomic_xchg(&s->message_lost, 0);
-
-       if (lost)
-               printk_deferred("Lost %d message(s)!\n", lost);
-}
-
-/*
- * Flush data from the associated per-CPU buffer. The function
- * can be called either via IRQ work or independently.
- */
-static void __printk_safe_flush(struct irq_work *work)
-{
-       struct printk_safe_seq_buf *s =
-               container_of(work, struct printk_safe_seq_buf, work);
-       unsigned long flags;
-       size_t len;
-       int i;
-
-       /*
-        * The lock has two functions. First, one reader has to flush all
-        * available message to make the lockless synchronization with
-        * writers easier. Second, we do not want to mix messages from
-        * different CPUs. This is especially important when printing
-        * a backtrace.
-        */
-       raw_spin_lock_irqsave(&safe_read_lock, flags);
-
-       i = 0;
-more:
-       len = atomic_read(&s->len);
-
-       /*
-        * This is just a paranoid check that nobody has manipulated
-        * the buffer an unexpected way. If we printed something then
-        * @len must only increase. Also it should never overflow the
-        * buffer size.
-        */
-       if ((i && i >= len) || len > sizeof(s->buffer)) {
-               const char *msg = "printk_safe_flush: internal error\n";
-
-               printk_safe_flush_line(msg, strlen(msg));
-               len = 0;
-       }
-
-       if (!len)
-               goto out; /* Someone else has already flushed the buffer. */
-
-       /* Make sure that data has been written up to the @len */
-       smp_rmb();
-       i += printk_safe_flush_buffer(s->buffer + i, len - i);
-
-       /*
-        * Check that nothing has got added in the meantime and truncate
-        * the buffer. Note that atomic_cmpxchg() is an implicit memory
-        * barrier that makes sure that the data were copied before
-        * updating s->len.
-        */
-       if (atomic_cmpxchg(&s->len, len, 0) != len)
-               goto more;
-
-out:
-       report_message_lost(s);
-       raw_spin_unlock_irqrestore(&safe_read_lock, flags);
-}
-
-/**
- * printk_safe_flush - flush all per-cpu nmi buffers.
- *
- * The buffers are flushed automatically via IRQ work. This function
- * is useful only when someone wants to be sure that all buffers have
- * been flushed at some point.
- */
-void printk_safe_flush(void)
-{
-       int cpu;
-
-       for_each_possible_cpu(cpu) {
-#ifdef CONFIG_PRINTK_NMI
-               __printk_safe_flush(&per_cpu(nmi_print_seq, cpu).work);
-#endif
-               __printk_safe_flush(&per_cpu(safe_print_seq, cpu).work);
-       }
-}
-
-/**
- * printk_safe_flush_on_panic - flush all per-cpu nmi buffers when the system
- *     goes down.
- *
- * Similar to printk_safe_flush() but it can be called even in NMI context when
- * the system goes down. It does the best effort to get NMI messages into
- * the main ring buffer.
- *
- * Note that it could try harder when there is only one CPU online.
- */
-void printk_safe_flush_on_panic(void)
-{
-       /*
-        * Make sure that we could access the main ring buffer.
-        * Do not risk a double release when more CPUs are up.
-        */
-       if (raw_spin_is_locked(&logbuf_lock)) {
-               if (num_online_cpus() > 1)
-                       return;
-
-               debug_locks_off();
-               raw_spin_lock_init(&logbuf_lock);
-       }
-
-       if (raw_spin_is_locked(&safe_read_lock)) {
-               if (num_online_cpus() > 1)
-                       return;
-
-               debug_locks_off();
-               raw_spin_lock_init(&safe_read_lock);
-       }
-
-       printk_safe_flush();
-}
-
-#ifdef CONFIG_PRINTK_NMI
-/*
- * Safe printk() for NMI context. It uses a per-CPU buffer to
- * store the message. NMIs are not nested, so there is always only
- * one writer running. But the buffer might get flushed from another
- * CPU, so we need to be careful.
- */
-static __printf(1, 0) int vprintk_nmi(const char *fmt, va_list args)
-{
-       struct printk_safe_seq_buf *s = this_cpu_ptr(&nmi_print_seq);
-
-       return printk_safe_log_store(s, fmt, args);
-}
-
-void noinstr printk_nmi_enter(void)
-{
-       this_cpu_add(printk_context, PRINTK_NMI_CONTEXT_OFFSET);
-}
-
-void noinstr printk_nmi_exit(void)
-{
-       this_cpu_sub(printk_context, PRINTK_NMI_CONTEXT_OFFSET);
-}
-
-/*
- * Marks a code that might produce many messages in NMI context
- * and the risk of losing them is more critical than eventual
- * reordering.
- *
- * It has effect only when called in NMI context. Then printk()
- * will try to store the messages into the main logbuf directly
- * and use the per-CPU buffers only as a fallback when the lock
- * is not available.
- */
-void printk_nmi_direct_enter(void)
-{
-       if (this_cpu_read(printk_context) & PRINTK_NMI_CONTEXT_MASK)
-               this_cpu_or(printk_context, PRINTK_NMI_DIRECT_CONTEXT_MASK);
-}
-
-void printk_nmi_direct_exit(void)
-{
-       this_cpu_and(printk_context, ~PRINTK_NMI_DIRECT_CONTEXT_MASK);
-}
-
-#else
-
-static __printf(1, 0) int vprintk_nmi(const char *fmt, va_list args)
-{
-       return 0;
-}
-
-#endif /* CONFIG_PRINTK_NMI */
-
-/*
- * Lock-less printk(), to avoid deadlocks should the printk() recurse
- * into itself. It uses a per-CPU buffer to store the message, just like
- * NMI.
- */
-static __printf(1, 0) int vprintk_safe(const char *fmt, va_list args)
-{
-       struct printk_safe_seq_buf *s = this_cpu_ptr(&safe_print_seq);
-
-       return printk_safe_log_store(s, fmt, args);
-}
-
-/* Can be preempted by NMI. */
-void __printk_safe_enter(void)
-{
-       this_cpu_inc(printk_context);
-}
-
-/* Can be preempted by NMI. */
-void __printk_safe_exit(void)
-{
-       this_cpu_dec(printk_context);
-}
-
-__printf(1, 0) int vprintk_func(const char *fmt, va_list args)
-{
-#ifdef CONFIG_KGDB_KDB
-       /* Allow to pass printk() to kdb but avoid a recursion. */
-       if (unlikely(kdb_trap_printk && kdb_printf_cpu < 0))
-               return vkdb_printf(KDB_MSGSRC_PRINTK, fmt, args);
-#endif
-
-       /*
-        * Try to use the main logbuf even in NMI. But avoid calling console
-        * drivers that might have their own locks.
-        */
-       if ((this_cpu_read(printk_context) & PRINTK_NMI_DIRECT_CONTEXT_MASK) &&
-           raw_spin_trylock(&logbuf_lock)) {
-               int len;
-
-               len = vprintk_store(0, LOGLEVEL_DEFAULT, NULL, fmt, args);
-               raw_spin_unlock(&logbuf_lock);
-               defer_console_output();
-               return len;
-       }
-
-       /* Use extra buffer in NMI when logbuf_lock is taken or in safe mode. */
-       if (this_cpu_read(printk_context) & PRINTK_NMI_CONTEXT_MASK)
-               return vprintk_nmi(fmt, args);
-
-       /* Use extra buffer to prevent a recursion deadlock in safe mode. */
-       if (this_cpu_read(printk_context) & PRINTK_SAFE_CONTEXT_MASK)
-               return vprintk_safe(fmt, args);
-
-       /* No obstacles. */
-       return vprintk_default(fmt, args);
-}
-
-void __init printk_safe_init(void)
-{
-       int cpu;
-
-       for_each_possible_cpu(cpu) {
-               struct printk_safe_seq_buf *s;
-
-               s = &per_cpu(safe_print_seq, cpu);
-               init_irq_work(&s->work, __printk_safe_flush);
-
-#ifdef CONFIG_PRINTK_NMI
-               s = &per_cpu(nmi_print_seq, cpu);
-               init_irq_work(&s->work, __printk_safe_flush);
-#endif
-       }
-
-       /* Flush pending messages that did not have scheduled IRQ works. */
-       printk_safe_flush();
-}
index eb4d04c..ec2d9fd 100644 (file)
@@ -196,7 +196,14 @@ static bool ptrace_freeze_traced(struct task_struct *task)
        spin_lock_irq(&task->sighand->siglock);
        if (task_is_traced(task) && !looks_like_a_spurious_pid(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);
@@ -206,8 +213,8 @@ static bool ptrace_freeze_traced(struct task_struct *task)
 
 static void ptrace_unfreeze_traced(struct task_struct *task)
 {
-       if (task->state != __TASK_TRACED)
-               return;
+       unsigned long flags;
+       bool frozen = true;
 
        WARN_ON(!task->ptrace || task->parent != current);
 
@@ -216,12 +223,19 @@ static void ptrace_unfreeze_traced(struct task_struct *task)
         * Recheck state under the lock to close this race.
         */
        spin_lock_irq(&task->sighand->siglock);
-       if (task->state == __TASK_TRACED) {
-               if (__fatal_signal_pending(task))
-                       wake_up_state(task, __TASK_TRACED);
-               else
-                       task->state = TASK_TRACED;
-       }
+
+       raw_spin_lock_irqsave(&task->pi_lock, flags);
+       if (task->state == __TASK_TRACED)
+               task->state = TASK_TRACED;
+       else if (task->saved_state == __TASK_TRACED)
+               task->saved_state = TASK_TRACED;
+       else
+               frozen = false;
+       raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+
+       if (frozen && __fatal_signal_pending(task))
+               wake_up_state(task, __TASK_TRACED);
+
        spin_unlock_irq(&task->sighand->siglock);
 }
 
index b71e21f..a2534cd 100644 (file)
@@ -188,8 +188,8 @@ config RCU_FAST_NO_HZ
 
 config RCU_BOOST
        bool "Enable RCU priority boosting"
-       depends on RT_MUTEXES && PREEMPT_RCU && RCU_EXPERT
-       default n
+       depends on (RT_MUTEXES && PREEMPT_RCU && RCU_EXPERT) || PREEMPT_RT
+       default y if PREEMPT_RT
        help
          This option boosts the priority of preempted RCU readers that
          block the current preemptible RCU grace period for too long.
index 844c358..5deac4e 100644 (file)
@@ -100,8 +100,10 @@ static struct rcu_state rcu_state = {
 static bool dump_tree;
 module_param(dump_tree, bool, 0444);
 /* By default, use RCU_SOFTIRQ instead of rcuc kthreads. */
-static bool use_softirq = true;
+static bool use_softirq = !IS_ENABLED(CONFIG_PREEMPT_RT);
+#ifndef CONFIG_PREEMPT_RT
 module_param(use_softirq, bool, 0444);
+#endif
 /* Control rcu_node-tree auto-balancing at boot time. */
 static bool rcu_fanout_exact;
 module_param(rcu_fanout_exact, bool, 0444);
index 849f0aa..dd94a60 100644 (file)
 #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);
+#ifndef CONFIG_PREEMPT_RT
 module_param(rcu_normal_after_boot, int, 0);
+#endif
 #endif /* #ifndef CONFIG_TINY_RCU */
 
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
index 1c7cf6d..b1271cf 100644 (file)
@@ -64,7 +64,11 @@ 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.
  */
+#ifdef CONFIG_PREEMPT_RT
+const_debug unsigned int sysctl_sched_nr_migrate = 8;
+#else
 const_debug unsigned int sysctl_sched_nr_migrate = 32;
+#endif
 
 /*
  * period over which we measure -rt task CPU usage in us.
@@ -510,9 +514,15 @@ static bool set_nr_if_polling(struct task_struct *p)
 #endif
 #endif
 
-static bool __wake_q_add(struct wake_q_head *head, struct task_struct *task)
+static bool __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
@@ -548,7 +558,13 @@ static bool __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)
 {
-       if (__wake_q_add(head, task))
+       if (__wake_q_add(head, task, false))
+               get_task_struct(task);
+}
+
+void wake_q_add_sleeper(struct wake_q_head *head, struct task_struct *task)
+{
+       if (__wake_q_add(head, task, true))
                get_task_struct(task);
 }
 
@@ -571,28 +587,39 @@ void wake_q_add(struct wake_q_head *head, struct task_struct *task)
  */
 void wake_q_add_safe(struct wake_q_head *head, struct task_struct *task)
 {
-       if (!__wake_q_add(head, task))
+       if (!__wake_q_add(head, task, false))
                put_task_struct(task);
 }
 
-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() executes a full barrier, which pairs 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);
        }
 }
@@ -628,6 +655,48 @@ void resched_curr(struct rq *rq)
                trace_sched_wake_idle_without_ipi(cpu);
 }
 
+#ifdef CONFIG_PREEMPT_LAZY
+
+static int tsk_is_polling(struct task_struct *p)
+{
+#ifdef TIF_POLLING_NRFLAG
+       return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG);
+#else
+       return 0;
+#endif
+}
+
+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);
@@ -1705,6 +1774,82 @@ void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags)
 
 #ifdef CONFIG_SMP
 
+static void
+__do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask, u32 flags);
+
+static int __set_cpus_allowed_ptr(struct task_struct *p,
+                                 const struct cpumask *new_mask,
+                                 u32 flags);
+
+static void migrate_disable_switch(struct rq *rq, struct task_struct *p)
+{
+       if (likely(!p->migration_disabled))
+               return;
+
+       if (p->cpus_ptr != &p->cpus_mask)
+               return;
+
+       /*
+        * Violates locking rules! see comment in __do_set_cpus_allowed().
+        */
+       __do_set_cpus_allowed(p, cpumask_of(rq->cpu), SCA_MIGRATE_DISABLE);
+}
+
+void migrate_disable(void)
+{
+       struct task_struct *p = current;
+
+       if (p->migration_disabled) {
+               p->migration_disabled++;
+               return;
+       }
+
+       trace_sched_migrate_disable_tp(p);
+
+       preempt_disable();
+       this_rq()->nr_pinned++;
+       p->migration_disabled = 1;
+       preempt_lazy_disable();
+       preempt_enable();
+}
+EXPORT_SYMBOL_GPL(migrate_disable);
+
+void migrate_enable(void)
+{
+       struct task_struct *p = current;
+
+       if (p->migration_disabled > 1) {
+               p->migration_disabled--;
+               return;
+       }
+
+       /*
+        * Ensure stop_task runs either before or after this, and that
+        * __set_cpus_allowed_ptr(SCA_MIGRATE_ENABLE) doesn't schedule().
+        */
+       preempt_disable();
+       if (p->cpus_ptr != &p->cpus_mask)
+               __set_cpus_allowed_ptr(p, &p->cpus_mask, SCA_MIGRATE_ENABLE);
+       /*
+        * Mustn't clear migration_disabled() until cpus_ptr points back at the
+        * regular cpus_mask, otherwise things that race (eg.
+        * select_fallback_rq) get confused.
+        */
+       barrier();
+       p->migration_disabled = 0;
+       this_rq()->nr_pinned--;
+       preempt_lazy_enable();
+       preempt_enable();
+
+       trace_sched_migrate_enable_tp(p);
+}
+EXPORT_SYMBOL_GPL(migrate_enable);
+
+static inline bool rq_has_pinned_tasks(struct rq *rq)
+{
+       return rq->nr_pinned;
+}
+
 /*
  * Per-CPU kthreads are allowed to run on !active && online CPUs, see
  * __set_cpus_allowed_ptr() and select_fallback_rq().
@@ -1714,7 +1859,7 @@ static inline bool is_cpu_allowed(struct task_struct *p, int cpu)
        if (!cpumask_test_cpu(cpu, p->cpus_ptr))
                return false;
 
-       if (is_per_cpu_kthread(p))
+       if (is_per_cpu_kthread(p) || is_migration_disabled(p))
                return cpu_online(cpu);
 
        return cpu_active(cpu);
@@ -1759,8 +1904,21 @@ static struct rq *move_queued_task(struct rq *rq, struct rq_flags *rf,
 }
 
 struct migration_arg {
-       struct task_struct *task;
-       int dest_cpu;
+       struct task_struct              *task;
+       int                             dest_cpu;
+       struct set_affinity_pending     *pending;
+};
+
+/*
+ * @refs: number of wait_for_completion()
+ * @stop_pending: is @stop_work in use
+ */
+struct set_affinity_pending {
+       refcount_t              refs;
+       unsigned int            stop_pending;
+       struct completion       done;
+       struct cpu_stop_work    stop_work;
+       struct migration_arg    arg;
 };
 
 /*
@@ -1793,15 +1951,17 @@ static struct rq *__migrate_task(struct rq *rq, struct rq_flags *rf,
 static int migration_cpu_stop(void *data)
 {
        struct migration_arg *arg = data;
+       struct set_affinity_pending *pending = arg->pending;
        struct task_struct *p = arg->task;
        struct rq *rq = this_rq();
+       bool complete = false;
        struct rq_flags rf;
 
        /*
         * The original target CPU might have gone down and we might
         * be on another CPU but it doesn't matter.
         */
-       local_irq_disable();
+       local_irq_save(rf.flags);
        /*
         * We need to explicitly wake pending tasks before running
         * __migrate_task() such that we will not miss enforcing cpus_ptr
@@ -1811,21 +1971,121 @@ static int migration_cpu_stop(void *data)
 
        raw_spin_lock(&p->pi_lock);
        rq_lock(rq, &rf);
+
        /*
         * If task_rq(p) != rq, it cannot be migrated here, because we're
         * holding rq->lock, if p->on_rq == 0 it cannot get enqueued because
         * we're holding p->pi_lock.
         */
        if (task_rq(p) == rq) {
+               if (is_migration_disabled(p))
+                       goto out;
+
+               if (pending) {
+                       if (p->migration_pending == pending)
+                               p->migration_pending = NULL;
+                       complete = true;
+
+                       if (cpumask_test_cpu(task_cpu(p), &p->cpus_mask))
+                               goto out;
+               }
+
                if (task_on_rq_queued(p))
                        rq = __migrate_task(rq, &rf, p, arg->dest_cpu);
                else
                        p->wake_cpu = arg->dest_cpu;
+
+               /*
+                * XXX __migrate_task() can fail, at which point we might end
+                * up running on a dodgy CPU, AFAICT this can only happen
+                * during CPU hotplug, at which point we'll get pushed out
+                * anyway, so it's probably not a big deal.
+                */
+
+       } else if (pending) {
+               /*
+                * This happens when we get migrated between migrate_enable()'s
+                * preempt_enable() and scheduling the stopper task. At that
+                * point we're a regular task again and not current anymore.
+                *
+                * A !PREEMPT kernel has a giant hole here, which makes it far
+                * more likely.
+                */
+
+               /*
+                * The task moved before the stopper got to run. We're holding
+                * ->pi_lock, so the allowed mask is stable - if it got
+                * somewhere allowed, we're done.
+                */
+               if (cpumask_test_cpu(task_cpu(p), p->cpus_ptr)) {
+                       if (p->migration_pending == pending)
+                               p->migration_pending = NULL;
+                       complete = true;
+                       goto out;
+               }
+
+               /*
+                * When migrate_enable() hits a rq mis-match we can't reliably
+                * determine is_migration_disabled() and so have to chase after
+                * it.
+                */
+               WARN_ON_ONCE(!pending->stop_pending);
+               task_rq_unlock(rq, p, &rf);
+               stop_one_cpu_nowait(task_cpu(p), migration_cpu_stop,
+                                   &pending->arg, &pending->stop_work);
+               return 0;
        }
-       rq_unlock(rq, &rf);
-       raw_spin_unlock(&p->pi_lock);
+out:
+       if (pending)
+               pending->stop_pending = false;
+       task_rq_unlock(rq, p, &rf);
+
+       if (complete)
+               complete_all(&pending->done);
 
-       local_irq_enable();
+       return 0;
+}
+
+int push_cpu_stop(void *arg)
+{
+       struct rq *lowest_rq = NULL, *rq = this_rq();
+       struct task_struct *p = arg;
+
+       raw_spin_lock_irq(&p->pi_lock);
+       raw_spin_lock(&rq->lock);
+
+       if (task_rq(p) != rq)
+               goto out_unlock;
+
+       if (is_migration_disabled(p)) {
+               p->migration_flags |= MDF_PUSH;
+               goto out_unlock;
+       }
+
+       p->migration_flags &= ~MDF_PUSH;
+
+       if (p->sched_class->find_lock_rq)
+               lowest_rq = p->sched_class->find_lock_rq(p, rq);
+
+       if (!lowest_rq)
+               goto out_unlock;
+
+       // XXX validate p is still the highest prio task
+       if (task_rq(p) == rq) {
+               deactivate_task(rq, p, 0);
+               set_task_cpu(p, lowest_rq->cpu);
+               activate_task(lowest_rq, p, 0);
+               resched_curr(lowest_rq);
+       }
+
+       double_unlock_balance(rq, lowest_rq);
+
+out_unlock:
+       rq->push_busy = false;
+       raw_spin_unlock(&rq->lock);
+       raw_spin_unlock_irq(&p->pi_lock);
+
+       put_task_struct(p);
        return 0;
 }
 
@@ -1833,18 +2093,39 @@ static int migration_cpu_stop(void *data)
  * sched_class::set_cpus_allowed must do the below, but is not required to
  * actually call this function.
  */
-void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask)
+void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask, u32 flags)
 {
+       if (flags & (SCA_MIGRATE_ENABLE | SCA_MIGRATE_DISABLE)) {
+               p->cpus_ptr = new_mask;
+               return;
+       }
+
        cpumask_copy(&p->cpus_mask, new_mask);
        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(struct task_struct *p, const struct cpumask *new_mask, u32 flags)
 {
        struct rq *rq = task_rq(p);
        bool queued, running;
 
-       lockdep_assert_held(&p->pi_lock);
+       /*
+        * This here violates the locking rules for affinity, since we're only
+        * supposed to change these variables while holding both rq->lock and
+        * p->pi_lock.
+        *
+        * HOWEVER, it magically works, because ttwu() is the only code that
+        * accesses these variables under p->pi_lock and only does so after
+        * smp_cond_load_acquire(&p->on_cpu, !VAL), and we're in __schedule()
+        * before finish_task().
+        *
+        * XXX do further audits, this smells like something putrid.
+        */
+       if (flags & SCA_MIGRATE_DISABLE)
+               SCHED_WARN_ON(!p->on_cpu);
+       else
+               lockdep_assert_held(&p->pi_lock);
 
        queued = task_on_rq_queued(p);
        running = task_current(rq, p);
@@ -1860,7 +2141,7 @@ void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
        if (running)
                put_prev_task(rq, p);
 
-       p->sched_class->set_cpus_allowed(p, new_mask);
+       p->sched_class->set_cpus_allowed(p, new_mask, flags);
 
        if (queued)
                enqueue_task(rq, p, ENQUEUE_RESTORE | ENQUEUE_NOCLOCK);
@@ -1868,6 +2149,222 @@ void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
                set_next_task(rq, p);
 }
 
+void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
+{
+       __do_set_cpus_allowed(p, new_mask, 0);
+}
+
+/*
+ * This function is wildly self concurrent; here be dragons.
+ *
+ *
+ * When given a valid mask, __set_cpus_allowed_ptr() must block until the
+ * designated task is enqueued on an allowed CPU. If that task is currently
+ * running, we have to kick it out using the CPU stopper.
+ *
+ * Migrate-Disable comes along and tramples all over our nice sandcastle.
+ * Consider:
+ *
+ *     Initial conditions: P0->cpus_mask = [0, 1]
+ *
+ *     P0@CPU0                  P1
+ *
+ *     migrate_disable();
+ *     <preempted>
+ *                              set_cpus_allowed_ptr(P0, [1]);
+ *
+ * P1 *cannot* return from this set_cpus_allowed_ptr() call until P0 executes
+ * its outermost migrate_enable() (i.e. it exits its Migrate-Disable region).
+ * This means we need the following scheme:
+ *
+ *     P0@CPU0                  P1
+ *
+ *     migrate_disable();
+ *     <preempted>
+ *                              set_cpus_allowed_ptr(P0, [1]);
+ *                                <blocks>
+ *     <resumes>
+ *     migrate_enable();
+ *       __set_cpus_allowed_ptr();
+ *       <wakes local stopper>
+ *                         `--> <woken on migration completion>
+ *
+ * Now the fun stuff: there may be several P1-like tasks, i.e. multiple
+ * concurrent set_cpus_allowed_ptr(P0, [*]) calls. CPU affinity changes of any
+ * task p are serialized by p->pi_lock, which we can leverage: the one that
+ * should come into effect at the end of the Migrate-Disable region is the last
+ * one. This means we only need to track a single cpumask (i.e. p->cpus_mask),
+ * but we still need to properly signal those waiting tasks at the appropriate
+ * moment.
+ *
+ * This is implemented using struct set_affinity_pending. The first
+ * __set_cpus_allowed_ptr() caller within a given Migrate-Disable region will
+ * setup an instance of that struct and install it on the targeted task_struct.
+ * Any and all further callers will reuse that instance. Those then wait for
+ * a completion signaled at the tail of the CPU stopper callback (1), triggered
+ * on the end of the Migrate-Disable region (i.e. outermost migrate_enable()).
+ *
+ *
+ * (1) In the cases covered above. There is one more where the completion is
+ * signaled within affine_move_task() itself: when a subsequent affinity request
+ * cancels the need for an active migration. Consider:
+ *
+ *     Initial conditions: P0->cpus_mask = [0, 1]
+ *
+ *     P0@CPU0            P1                             P2
+ *
+ *     migrate_disable();
+ *     <preempted>
+ *                        set_cpus_allowed_ptr(P0, [1]);
+ *                          <blocks>
+ *                                                       set_cpus_allowed_ptr(P0, [0, 1]);
+ *                                                         <signal completion>
+ *                          <awakes>
+ *
+ * Note that the above is safe vs a concurrent migrate_enable(), as any
+ * pending affinity completion is preceded an uninstallion of
+ * p->migration_pending done with p->pi_lock held.
+ */
+static int affine_move_task(struct rq *rq, struct task_struct *p, struct rq_flags *rf,
+                           int dest_cpu, unsigned int flags)
+{
+       struct set_affinity_pending my_pending = { }, *pending = NULL;
+       bool stop_pending, complete = false;
+
+       /* Can the task run on the task's current CPU? If so, we're done */
+       if (cpumask_test_cpu(task_cpu(p), &p->cpus_mask)) {
+               struct task_struct *push_task = NULL;
+
+               if ((flags & SCA_MIGRATE_ENABLE) &&
+                   (p->migration_flags & MDF_PUSH) && !rq->push_busy) {
+                       rq->push_busy = true;
+                       push_task = get_task_struct(p);
+               }
+
+               /*
+                * If there are pending waiters, but no pending stop_work,
+                * then complete now.
+                */
+               pending = p->migration_pending;
+               if (pending && !pending->stop_pending) {
+                       p->migration_pending = NULL;
+                       complete = true;
+               }
+
+               task_rq_unlock(rq, p, rf);
+
+               if (push_task) {
+                       stop_one_cpu_nowait(rq->cpu, push_cpu_stop,
+                                           p, &rq->push_work);
+               }
+
+               if (complete)
+                       complete_all(&pending->done);
+
+               return 0;
+       }
+
+       if (!(flags & SCA_MIGRATE_ENABLE)) {
+               /* serialized by p->pi_lock */
+               if (!p->migration_pending) {
+                       /* Install the request */
+                       refcount_set(&my_pending.refs, 1);
+                       init_completion(&my_pending.done);
+                       my_pending.arg = (struct migration_arg) {
+                               .task = p,
+                               .dest_cpu = dest_cpu,
+                               .pending = &my_pending,
+                       };
+
+                       p->migration_pending = &my_pending;
+               } else {
+                       pending = p->migration_pending;
+                       refcount_inc(&pending->refs);
+                       /*
+                        * Affinity has changed, but we've already installed a
+                        * pending. migration_cpu_stop() *must* see this, else
+                        * we risk a completion of the pending despite having a
+                        * task on a disallowed CPU.
+                        *
+                        * Serialized by p->pi_lock, so this is safe.
+                        */
+                       pending->arg.dest_cpu = dest_cpu;
+               }
+       }
+       pending = p->migration_pending;
+       /*
+        * - !MIGRATE_ENABLE:
+        *   we'll have installed a pending if there wasn't one already.
+        *
+        * - MIGRATE_ENABLE:
+        *   we're here because the current CPU isn't matching anymore,
+        *   the only way that can happen is because of a concurrent
+        *   set_cpus_allowed_ptr() call, which should then still be
+        *   pending completion.
+        *
+        * Either way, we really should have a @pending here.
+        */
+       if (WARN_ON_ONCE(!pending)) {
+               task_rq_unlock(rq, p, rf);
+               return -EINVAL;
+       }
+
+       if (task_running(rq, p) || p->state == TASK_WAKING) {
+               /*
+                * MIGRATE_ENABLE gets here because 'p == current', but for
+                * anything else we cannot do is_migration_disabled(), punt
+                * and have the stopper function handle it all race-free.
+                */
+               stop_pending = pending->stop_pending;
+               if (!stop_pending)
+                       pending->stop_pending = true;
+
+               if (flags & SCA_MIGRATE_ENABLE)
+                       p->migration_flags &= ~MDF_PUSH;
+
+               task_rq_unlock(rq, p, rf);
+
+               if (!stop_pending) {
+                       stop_one_cpu_nowait(cpu_of(rq), migration_cpu_stop,
+                                           &pending->arg, &pending->stop_work);
+               }
+
+               if (flags & SCA_MIGRATE_ENABLE)
+                       return 0;
+       } else {
+
+               if (!is_migration_disabled(p)) {
+                       if (task_on_rq_queued(p))
+                               rq = move_queued_task(rq, rf, p, dest_cpu);
+
+                       if (!pending->stop_pending) {
+                               p->migration_pending = NULL;
+                               complete = true;
+                       }
+               }
+               task_rq_unlock(rq, p, rf);
+
+               if (complete)
+                       complete_all(&pending->done);
+       }
+
+       wait_for_completion(&pending->done);
+
+       if (refcount_dec_and_test(&pending->refs))
+               wake_up_var(&pending->refs); /* No UaF, just an address */
+
+       /*
+        * Block the original owner of &pending until all subsequent callers
+        * have seen the completion and decremented the refcount
+        */
+       wait_var_event(&my_pending.refs, !refcount_read(&my_pending.refs));
+
+       /* ARGH */
+       WARN_ON_ONCE(my_pending.stop_pending);
+
+       return 0;
+}
+
 /*
  * 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
@@ -1878,7 +2375,8 @@ void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
  * call is not atomic; no spinlocks may be held.
  */
 static int __set_cpus_allowed_ptr(struct task_struct *p,
-                                 const struct cpumask *new_mask, bool check)
+                                 const struct cpumask *new_mask,
+                                 u32 flags)
 {
        const struct cpumask *cpu_valid_mask = cpu_active_mask;
        unsigned int dest_cpu;
@@ -1889,9 +2387,14 @@ static int __set_cpus_allowed_ptr(struct task_struct *p,
        rq = task_rq_lock(p, &rf);
        update_rq_clock(rq);
 
-       if (p->flags & PF_KTHREAD) {
+       if (p->flags & PF_KTHREAD || is_migration_disabled(p)) {
                /*
-                * Kernel threads are allowed on online && !active CPUs
+                * Kernel threads are allowed on online && !active CPUs.
+                *
+                * Specifically, migration_disabled() tasks must not fail the
+                * cpumask_any_and_distribute() pick below, esp. so on
+                * SCA_MIGRATE_ENABLE, otherwise we'll not call
+                * set_cpus_allowed_common() and actually reset p->cpus_ptr.
                 */
                cpu_valid_mask = cpu_online_mask;
        }
@@ -1900,13 +2403,22 @@ static int __set_cpus_allowed_ptr(struct task_struct *p,
         * Must re-check here, to close a race against __kthread_bind(),
         * sched_setaffinity() is not guaranteed to observe the flag.
         */
-       if (check && (p->flags & PF_NO_SETAFFINITY)) {
+       if ((flags & SCA_CHECK) && (p->flags & PF_NO_SETAFFINITY)) {
                ret = -EINVAL;
                goto out;
        }
 
-       if (cpumask_equal(&p->cpus_mask, new_mask))
-               goto out;
+       if (!(flags & SCA_MIGRATE_ENABLE)) {
+               if (cpumask_equal(&p->cpus_mask, new_mask))
+                       goto out;
+
+               if (WARN_ON_ONCE(p == current &&
+                                is_migration_disabled(p) &&
+                                !cpumask_test_cpu(task_cpu(p), new_mask))) {
+                       ret = -EBUSY;
+                       goto out;
+               }
+       }
 
        /*
         * Picking a ~random cpu helps in cases where we are changing affinity
@@ -1919,7 +2431,7 @@ static int __set_cpus_allowed_ptr(struct task_struct *p,
                goto out;
        }
 
-       do_set_cpus_allowed(p, new_mask);
+       __do_set_cpus_allowed(p, new_mask, flags);
 
        if (p->flags & PF_KTHREAD) {
                /*
@@ -1931,23 +2443,8 @@ static int __set_cpus_allowed_ptr(struct task_struct *p,
                        p->nr_cpus_allowed != 1);
        }
 
-       /* Can the task run on the task's current CPU? If so, we're done */
-       if (cpumask_test_cpu(task_cpu(p), new_mask))
-               goto out;
+       return affine_move_task(rq, p, &rf, dest_cpu, flags);
 
-       if (task_running(rq, p) || p->state == TASK_WAKING) {
-               struct migration_arg arg = { p, dest_cpu };
-               /* Need help from migration thread: drop lock and wait. */
-               task_rq_unlock(rq, p, &rf);
-               stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg);
-               return 0;
-       } else if (task_on_rq_queued(p)) {
-               /*
-                * OK, since we're going to drop the lock immediately
-                * afterwards anyway.
-                */
-               rq = move_queued_task(rq, &rf, p, dest_cpu);
-       }
 out:
        task_rq_unlock(rq, p, &rf);
 
@@ -1956,7 +2453,7 @@ out:
 
 int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
 {
-       return __set_cpus_allowed_ptr(p, new_mask, false);
+       return __set_cpus_allowed_ptr(p, new_mask, 0);
 }
 EXPORT_SYMBOL_GPL(set_cpus_allowed_ptr);
 
@@ -1997,6 +2494,8 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu)
         * Clearly, migrating tasks to offline CPUs is a fairly daft thing.
         */
        WARN_ON_ONCE(!cpu_online(new_cpu));
+
+       WARN_ON_ONCE(is_migration_disabled(p));
 #endif
 
        trace_sched_migrate_task(p, new_cpu);
@@ -2129,6 +2628,18 @@ out:
 }
 #endif /* CONFIG_NUMA_BALANCING */
 
+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.
  *
@@ -2173,7 +2684,7 @@ 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();
                }
@@ -2188,7 +2699,8 @@ 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);
 
@@ -2222,7 +2734,7 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state)
                        ktime_t to = NSEC_PER_SEC / HZ;
 
                        set_current_state(TASK_UNINTERRUPTIBLE);
-                       schedule_hrtimeout(&to, HRTIMER_MODE_REL);
+                       schedule_hrtimeout(&to, HRTIMER_MODE_REL_HARD);
                        continue;
                }
 
@@ -2327,6 +2839,12 @@ static int select_fallback_rq(int cpu, struct task_struct *p)
                        }
                        fallthrough;
                case possible:
+                       /*
+                        * XXX When called from select_task_rq() we only
+                        * hold p->pi_lock and again violate locking order.
+                        *
+                        * More yuck to audit.
+                        */
                        do_set_cpus_allowed(p, cpu_possible_mask);
                        state = fail;
                        break;
@@ -2361,7 +2879,7 @@ int select_task_rq(struct task_struct *p, int cpu, int sd_flags, int wake_flags)
 {
        lockdep_assert_held(&p->pi_lock);
 
-       if (p->nr_cpus_allowed > 1)
+       if (p->nr_cpus_allowed > 1 && !is_migration_disabled(p))
                cpu = p->sched_class->select_task_rq(p, cpu, sd_flags, wake_flags);
        else
                cpu = cpumask_any(p->cpus_ptr);
@@ -2384,6 +2902,7 @@ int select_task_rq(struct task_struct *p, int cpu, int sd_flags, int wake_flags)
 
 void sched_set_stop_task(int cpu, struct task_struct *stop)
 {
+       static struct lock_class_key stop_pi_lock;
        struct sched_param param = { .sched_priority = MAX_RT_PRIO - 1 };
        struct task_struct *old_stop = cpu_rq(cpu)->stop;
 
@@ -2399,6 +2918,20 @@ void sched_set_stop_task(int cpu, struct task_struct *stop)
                sched_setscheduler_nocheck(stop, SCHED_FIFO, &param);
 
                stop->sched_class = &stop_sched_class;
+
+               /*
+                * The PI code calls rt_mutex_setprio() with ->pi_lock held to
+                * adjust the effective priority of a task. As a result,
+                * rt_mutex_setprio() can trigger (RT) balancing operations,
+                * which can then trigger wakeups of the stop thread to push
+                * around the current task.
+                *
+                * The stop task itself will never be part of the PI-chain, it
+                * never blocks, therefore that ->pi_lock recursion is safe.
+                * Tell lockdep about this by placing the stop->pi_lock in its
+                * own class.
+                */
+               lockdep_set_class(&stop->pi_lock, &stop_pi_lock);
        }
 
        cpu_rq(cpu)->stop = stop;
@@ -2412,15 +2945,23 @@ void sched_set_stop_task(int cpu, struct task_struct *stop)
        }
 }
 
-#else
+#else /* CONFIG_SMP */
 
 static inline int __set_cpus_allowed_ptr(struct task_struct *p,
-                                        const struct cpumask *new_mask, bool check)
+                                        const struct cpumask *new_mask,
+                                        u32 flags)
 {
        return set_cpus_allowed_ptr(p, new_mask);
 }
 
-#endif /* CONFIG_SMP */
+static inline void migrate_disable_switch(struct rq *rq, struct task_struct *p) { }
+
+static inline bool rq_has_pinned_tasks(struct rq *rq)
+{
+       return false;
+}
+
+#endif /* !CONFIG_SMP */
 
 static void
 ttwu_stat(struct task_struct *p, int cpu, int wake_flags)
@@ -2841,7 +3382,7 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
        int cpu, success = 0;
 
        preempt_disable();
-       if (p == current) {
+       if (!IS_ENABLED(CONFIG_PREEMPT_RT) && p == current) {
                /*
                 * We're waking current, this means 'p->on_rq' and 'task_cpu(p)
                 * == smp_processor_id()'. Together this means we can special
@@ -2871,8 +3412,26 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
         */
        raw_spin_lock_irqsave(&p->pi_lock, flags);
        smp_mb__after_spinlock();
-       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 unlock;
+       }
+       /*
+        * 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);
 
@@ -3061,6 +3620,18 @@ 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);
@@ -3114,6 +3685,7 @@ static void __sched_fork(unsigned long clone_flags, struct task_struct *p)
        init_numa_balancing(clone_flags, p);
 #ifdef CONFIG_SMP
        p->wake_entry.u_flags = CSD_TYPE_TTWU;
+       p->migration_pending = NULL;
 #endif
 }
 
@@ -3287,6 +3859,9 @@ 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);
@@ -3459,49 +4034,133 @@ fire_sched_out_preempt_notifiers(struct task_struct *curr,
 
 #else /* !CONFIG_PREEMPT_NOTIFIERS */
 
-static inline void fire_sched_in_preempt_notifiers(struct task_struct *curr)
+static inline void fire_sched_in_preempt_notifiers(struct task_struct *curr)
+{
+}
+
+static inline void
+fire_sched_out_preempt_notifiers(struct task_struct *curr,
+                                struct task_struct *next)
+{
+}
+
+#endif /* CONFIG_PREEMPT_NOTIFIERS */
+
+static inline void prepare_task(struct task_struct *next)
+{
+#ifdef CONFIG_SMP
+       /*
+        * Claim the task as running, we do this before switching to it
+        * such that any running task will have this set.
+        *
+        * See the ttwu() WF_ON_CPU case and its ordering comment.
+        */
+       WRITE_ONCE(next->on_cpu, 1);
+#endif
+}
+
+static inline void finish_task(struct task_struct *prev)
+{
+#ifdef CONFIG_SMP
+       /*
+        * This must be the very last reference to @prev from this CPU. After
+        * p->on_cpu is cleared, the task can be moved to a different CPU. We
+        * must ensure this doesn't happen until the switch is completely
+        * finished.
+        *
+        * In particular, the load of prev->state in finish_task_switch() must
+        * happen before this.
+        *
+        * Pairs with the smp_cond_load_acquire() in try_to_wake_up().
+        */
+       smp_store_release(&prev->on_cpu, 0);
+#endif
+}
+
+#ifdef CONFIG_SMP
+
+static void do_balance_callbacks(struct rq *rq, struct callback_head *head)
+{
+       void (*func)(struct rq *rq);
+       struct callback_head *next;
+
+       lockdep_assert_held(&rq->lock);
+
+       while (head) {
+               func = (void (*)(struct rq *))head->func;
+               next = head->next;
+               head->next = NULL;
+               head = next;
+
+               func(rq);
+       }
+}
+
+static inline struct callback_head *splice_balance_callbacks(struct rq *rq)
+{
+       struct callback_head *head = rq->balance_callback;
+
+       lockdep_assert_held(&rq->lock);
+       if (head) {
+               rq->balance_callback = NULL;
+               rq->balance_flags &= ~BALANCE_WORK;
+       }
+
+       return head;
+}
+
+static void __balance_callbacks(struct rq *rq)
+{
+       do_balance_callbacks(rq, splice_balance_callbacks(rq));
+}
+
+static inline void balance_callbacks(struct rq *rq, struct callback_head *head)
+{
+       unsigned long flags;
+
+       if (unlikely(head)) {
+               raw_spin_lock_irqsave(&rq->lock, flags);
+               do_balance_callbacks(rq, head);
+               raw_spin_unlock_irqrestore(&rq->lock, flags);
+       }
+}
+
+static void balance_push(struct rq *rq);
+
+static inline void balance_switch(struct rq *rq)
+{
+       if (likely(!rq->balance_flags))
+               return;
+
+       if (rq->balance_flags & BALANCE_PUSH) {
+               balance_push(rq);
+               return;
+       }
+
+       __balance_callbacks(rq);
+}
+
+#else
+
+static inline void __balance_callbacks(struct rq *rq)
 {
 }
 
-static inline void
-fire_sched_out_preempt_notifiers(struct task_struct *curr,
-                                struct task_struct *next)
+static inline struct callback_head *splice_balance_callbacks(struct rq *rq)
 {
+       return NULL;
 }
 
-#endif /* CONFIG_PREEMPT_NOTIFIERS */
-
-static inline void prepare_task(struct task_struct *next)
+static inline void balance_callbacks(struct rq *rq, struct callback_head *head)
 {
-#ifdef CONFIG_SMP
-       /*
-        * Claim the task as running, we do this before switching to it
-        * such that any running task will have this set.
-        *
-        * See the ttwu() WF_ON_CPU case and its ordering comment.
-        */
-       WRITE_ONCE(next->on_cpu, 1);
-#endif
 }
 
-static inline void finish_task(struct task_struct *prev)
+static inline void balance_switch(struct rq *rq)
 {
-#ifdef CONFIG_SMP
-       /*
-        * This must be the very last reference to @prev from this CPU. After
-        * p->on_cpu is cleared, the task can be moved to a different CPU. We
-        * must ensure this doesn't happen until the switch is completely
-        * finished.
-        *
-        * In particular, the load of prev->state in finish_task_switch() must
-        * happen before this.
-        *
-        * Pairs with the smp_cond_load_acquire() in try_to_wake_up().
-        */
-       smp_store_release(&prev->on_cpu, 0);
-#endif
 }
 
+#endif
+
 static inline void
 prepare_lock_switch(struct rq *rq, struct task_struct *next, struct rq_flags *rf)
 {
@@ -3527,6 +4186,7 @@ static inline void finish_lock_switch(struct rq *rq)
         * prev into current:
         */
        spin_acquire(&rq->lock.dep_map, 0, 0, _THIS_IP_);
+       balance_switch(rq);
        raw_spin_unlock_irq(&rq->lock);
 }
 
@@ -3542,6 +4202,22 @@ static inline void finish_lock_switch(struct rq *rq)
 # define finish_arch_post_lock_switch()        do { } while (0)
 #endif
 
+static inline void kmap_local_sched_out(void)
+{
+#ifdef CONFIG_KMAP_LOCAL
+       if (unlikely(current->kmap_ctrl.idx))
+               __kmap_local_sched_out();
+#endif
+}
+
+static inline void kmap_local_sched_in(void)
+{
+#ifdef CONFIG_KMAP_LOCAL
+       if (unlikely(current->kmap_ctrl.idx))
+               __kmap_local_sched_in();
+#endif
+}
+
 /**
  * prepare_task_switch - prepare to switch tasks
  * @rq: the runqueue preparing to switch
@@ -3564,6 +4240,7 @@ prepare_task_switch(struct rq *rq, struct task_struct *prev,
        perf_event_task_sched_out(prev, next);
        rseq_preempt(prev);
        fire_sched_out_preempt_notifiers(prev, next);
+       kmap_local_sched_out();
        prepare_task(next);
        prepare_arch_switch(next);
 }
@@ -3630,6 +4307,7 @@ static struct rq *finish_task_switch(struct task_struct *prev)
        finish_lock_switch(rq);
        finish_arch_post_lock_switch();
        kcov_finish_switch(current);
+       kmap_local_sched_in();
 
        fire_sched_in_preempt_notifiers(current);
        /*
@@ -3644,23 +4322,18 @@ static struct rq *finish_task_switch(struct task_struct *prev)
         *   provided by mmdrop(),
         * - a sync_core for SYNC_CORE.
         */
+       /*
+        * We use mmdrop_delayed() here so we don't have to do the
+        * full __mmdrop() when we are the last user.
+        */
        if (mm) {
                membarrier_mm_sync_core_before_usermode(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_rcu_user(prev);
        }
 
@@ -3668,43 +4341,6 @@ static struct rq *finish_task_switch(struct task_struct *prev)
        return rq;
 }
 
-#ifdef CONFIG_SMP
-
-/* rq->lock is NOT held, but preemption is disabled */
-static void __balance_callback(struct rq *rq)
-{
-       struct callback_head *head, *next;
-       void (*func)(struct rq *rq);
-       unsigned long flags;
-
-       raw_spin_lock_irqsave(&rq->lock, flags);
-       head = rq->balance_callback;
-       rq->balance_callback = NULL;
-       while (head) {
-               func = (void (*)(struct rq *))head->func;
-               next = head->next;
-               head->next = NULL;
-               head = next;
-
-               func(rq);
-       }
-       raw_spin_unlock_irqrestore(&rq->lock, flags);
-}
-
-static inline void balance_callback(struct rq *rq)
-{
-       if (unlikely(rq->balance_callback))
-               __balance_callback(rq);
-}
-
-#else
-
-static inline void balance_callback(struct rq *rq)
-{
-}
-
-#endif
-
 /**
  * schedule_tail - first thing a freshly forked thread must call.
  * @prev: the thread we just switched away from.
@@ -3724,7 +4360,6 @@ asmlinkage __visible void schedule_tail(struct task_struct *prev)
         */
 
        rq = finish_task_switch(prev);
-       balance_callback(rq);
        preempt_enable();
 
        if (current->set_child_tid)
@@ -4419,7 +5054,7 @@ restart:
  *
  * WARNING: must be called with preemption disabled!
  */
-static void __sched notrace __schedule(bool preempt)
+static void __sched notrace __schedule(bool preempt, bool spinning_lock)
 {
        struct task_struct *prev, *next;
        unsigned long *switch_count;
@@ -4472,7 +5107,7 @@ static void __sched notrace __schedule(bool preempt)
         *  - ptrace_{,un}freeze_traced() can change ->state underneath us.
         */
        prev_state = prev->state;
-       if (!preempt && prev_state) {
+       if ((!preempt || spinning_lock) && prev_state) {
                if (signal_pending_state(prev_state, prev)) {
                        prev->state = TASK_RUNNING;
                } else {
@@ -4507,6 +5142,7 @@ static void __sched notrace __schedule(bool preempt)
 
        next = pick_next_task(rq, prev, &rf);
        clear_tsk_need_resched(prev);
+       clear_tsk_need_resched_lazy(prev);
        clear_preempt_need_resched();
 
        if (likely(prev != next)) {
@@ -4532,6 +5168,7 @@ static void __sched notrace __schedule(bool preempt)
                 */
                ++*switch_count;
 
+               migrate_disable_switch(rq, prev);
                psi_sched_switch(prev, next, !task_on_rq_queued(prev));
 
                trace_sched_switch(preempt, prev, next);
@@ -4540,10 +5177,11 @@ static void __sched notrace __schedule(bool preempt)
                rq = context_switch(rq, prev, next, &rf);
        } else {
                rq->clock_update_flags &= ~(RQCF_ACT_SKIP|RQCF_REQ_SKIP);
-               rq_unlock_irq(rq, &rf);
-       }
 
-       balance_callback(rq);
+               rq_unpin_lock(rq, &rf);
+               __balance_callbacks(rq);
+               raw_spin_unlock_irq(&rq->lock);
+       }
 }
 
 void __noreturn do_task_dead(void)
@@ -4554,7 +5192,7 @@ void __noreturn do_task_dead(void)
        /* Tell freezer to ignore us: */
        current->flags |= PF_NOFREEZE;
 
-       __schedule(false);
+       __schedule(false, false);
        BUG();
 
        /* Avoid "noreturn function does return" - but don't continue if BUG() is a NOP: */
@@ -4587,9 +5225,6 @@ static inline void sched_submit_work(struct task_struct *tsk)
                preempt_enable_no_resched();
        }
 
-       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.
@@ -4615,7 +5250,7 @@ asmlinkage __visible void __sched schedule(void)
        sched_submit_work(tsk);
        do {
                preempt_disable();
-               __schedule(false);
+               __schedule(false, false);
                sched_preempt_enable_no_resched();
        } while (need_resched());
        sched_update_worker(tsk);
@@ -4643,7 +5278,7 @@ void __sched schedule_idle(void)
         */
        WARN_ON_ONCE(current->state);
        do {
-               __schedule(false);
+               __schedule(false, false);
        } while (need_resched());
 }
 
@@ -4696,7 +5331,7 @@ static void __sched notrace preempt_schedule_common(void)
                 */
                preempt_disable_notrace();
                preempt_latency_start(1);
-               __schedule(true);
+               __schedule(true, false);
                preempt_latency_stop(1);
                preempt_enable_no_resched_notrace();
 
@@ -4707,6 +5342,30 @@ 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_PREEMPTION
 /*
  * This is the entry point to schedule() from in-kernel preemption
@@ -4720,12 +5379,26 @@ asmlinkage __visible void __sched notrace preempt_schedule(void)
         */
        if (likely(!preemptible()))
                return;
-
+       if (!preemptible_lazy())
+               return;
        preempt_schedule_common();
 }
 NOKPROBE_SYMBOL(preempt_schedule);
 EXPORT_SYMBOL(preempt_schedule);
 
+#ifdef CONFIG_PREEMPT_RT
+void __sched notrace preempt_schedule_lock(void)
+{
+       do {
+               preempt_disable();
+               __schedule(true, true);
+               sched_preempt_enable_no_resched();
+       } while (need_resched());
+}
+NOKPROBE_SYMBOL(preempt_schedule_lock);
+EXPORT_SYMBOL(preempt_schedule_lock);
+#endif
+
 /**
  * preempt_schedule_notrace - preempt_schedule called by tracing
  *
@@ -4747,6 +5420,9 @@ 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()
@@ -4769,7 +5445,7 @@ asmlinkage __visible void __sched notrace preempt_schedule_notrace(void)
                 * an infinite recursion.
                 */
                prev_ctx = exception_enter();
-               __schedule(true);
+               __schedule(true, false);
                exception_exit(prev_ctx);
 
                preempt_latency_stop(1);
@@ -4798,7 +5474,7 @@ asmlinkage __visible void __sched preempt_schedule_irq(void)
        do {
                preempt_disable();
                local_irq_enable();
-               __schedule(true);
+               __schedule(true, false);
                local_irq_disable();
                sched_preempt_enable_no_resched();
        } while (need_resched());
@@ -4964,9 +5640,11 @@ void rt_mutex_setprio(struct task_struct *p, struct task_struct *pi_task)
 out_unlock:
        /* Avoid rq from going away on us: */
        preempt_disable();
-       __task_rq_unlock(rq, &rf);
 
-       balance_callback(rq);
+       rq_unpin_lock(rq, &rf);
+       __balance_callbacks(rq);
+       raw_spin_unlock(&rq->lock);
+
        preempt_enable();
 }
 #else
@@ -5209,6 +5887,7 @@ static int __sched_setscheduler(struct task_struct *p,
        int oldpolicy = -1, policy = attr->sched_policy;
        int retval, oldprio, newprio, queued, running;
        const struct sched_class *prev_class;
+       struct callback_head *head;
        struct rq_flags rf;
        int reset_on_fork;
        int queue_flags = DEQUEUE_SAVE | DEQUEUE_MOVE | DEQUEUE_NOCLOCK;
@@ -5451,6 +6130,7 @@ change:
 
        /* Avoid rq from going away on us: */
        preempt_disable();
+       head = splice_balance_callbacks(rq);
        task_rq_unlock(rq, p, &rf);
 
        if (pi) {
@@ -5459,7 +6139,7 @@ change:
        }
 
        /* Run balance callbacks after we've adjusted the PI chain: */
-       balance_callback(rq);
+       balance_callbacks(rq, head);
        preempt_enable();
 
        return 0;
@@ -5957,7 +6637,7 @@ long sched_setaffinity(pid_t pid, const struct cpumask *in_mask)
        }
 #endif
 again:
-       retval = __set_cpus_allowed_ptr(p, new_mask, true);
+       retval = __set_cpus_allowed_ptr(p, new_mask, SCA_CHECK);
 
        if (!retval) {
                cpuset_cpus_allowed(p, cpus_allowed);
@@ -6533,7 +7213,7 @@ void __init init_idle(struct task_struct *idle, int cpu)
         *
         * And since this is boot we can forgo the serialization.
         */
-       set_cpus_allowed_common(idle, cpumask_of(cpu));
+       set_cpus_allowed_common(idle, cpumask_of(cpu), 0);
 #endif
        /*
         * We're having a chicken and egg problem, even though we are
@@ -6560,7 +7240,9 @@ void __init 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:
         */
@@ -6665,6 +7347,7 @@ void sched_setnuma(struct task_struct *p, int nid)
 #endif /* CONFIG_NUMA_BALANCING */
 
 #ifdef CONFIG_HOTPLUG_CPU
+
 /*
  * Ensure that the idle task is using init_mm right before its CPU goes
  * offline.
@@ -6684,119 +7367,126 @@ void idle_task_exit(void)
        /* finish_cpu(), as ran on the BP, will clean up the active_mm state */
 }
 
-/*
- * Since this CPU is going 'away' for a while, fold any nr_active delta
- * we might have. Assumes we're called after migrate_tasks() so that the
- * nr_active count is stable. We need to take the teardown thread which
- * is calling this into account, so we hand in adjust = 1 to the load
- * calculation.
- *
- * Also see the comment "Global load-average calculations".
- */
-static void calc_load_migrate(struct rq *rq)
+static int __balance_push_cpu_stop(void *arg)
 {
-       long delta = calc_load_fold_active(rq, 1);
-       if (delta)
-               atomic_long_add(delta, &calc_load_tasks);
-}
+       struct task_struct *p = arg;
+       struct rq *rq = this_rq();
+       struct rq_flags rf;
+       int cpu;
 
-static struct task_struct *__pick_migrate_task(struct rq *rq)
-{
-       const struct sched_class *class;
-       struct task_struct *next;
+       raw_spin_lock_irq(&p->pi_lock);
+       rq_lock(rq, &rf);
 
-       for_each_class(class) {
-               next = class->pick_next_task(rq);
-               if (next) {
-                       next->sched_class->put_prev_task(rq, next);
-                       return next;
-               }
+       update_rq_clock(rq);
+
+       if (task_rq(p) == rq && task_on_rq_queued(p)) {
+               cpu = select_fallback_rq(rq->cpu, p);
+               rq = __migrate_task(rq, &rf, p, cpu);
        }
 
-       /* The idle class should always have a runnable task */
-       BUG();
+       rq_unlock(rq, &rf);
+       raw_spin_unlock_irq(&p->pi_lock);
+
+       put_task_struct(p);
+
+       return 0;
 }
 
+static DEFINE_PER_CPU(struct cpu_stop_work, push_work);
+
 /*
- * Migrate all tasks from the rq, sleeping tasks will be migrated by
- * try_to_wake_up()->select_task_rq().
- *
- * Called with rq->lock held even though we'er in stop_machine() and
- * there's no concurrency possible, we hold the required locks anyway
- * because of lock validation efforts.
+ * Ensure we only run per-cpu kthreads once the CPU goes !active.
  */
-static void migrate_tasks(struct rq *dead_rq, struct rq_flags *rf)
+static void balance_push(struct rq *rq)
 {
-       struct rq *rq = dead_rq;
-       struct task_struct *next, *stop = rq->stop;
-       struct rq_flags orf = *rf;
-       int dest_cpu;
+       struct task_struct *push_task = rq->curr;
+
+       lockdep_assert_held(&rq->lock);
+       SCHED_WARN_ON(rq->cpu != smp_processor_id());
 
        /*
-        * Fudge the rq selection such that the below task selection loop
-        * doesn't get stuck on the currently eligible stop task.
-        *
-        * We're currently inside stop_machine() and the rq is either stuck
-        * in the stop_machine_cpu_stop() loop, or we're executing this code,
-        * either way we should never end up calling schedule() until we're
-        * done here.
+        * Both the cpu-hotplug and stop task are in this case and are
+        * required to complete the hotplug process.
         */
-       rq->stop = NULL;
+       if (is_per_cpu_kthread(push_task) || is_migration_disabled(push_task)) {
+               /*
+                * If this is the idle task on the outgoing CPU try to wake
+                * up the hotplug control thread which might wait for the
+                * last task to vanish. The rcuwait_active() check is
+                * accurate here because the waiter is pinned on this CPU
+                * and can't obviously be running in parallel.
+                *
+                * On RT kernels this also has to check whether there are
+                * pinned and scheduled out tasks on the runqueue. They
+                * need to leave the migrate disabled section first.
+                */
+               if (!rq->nr_running && !rq_has_pinned_tasks(rq) &&
+                   rcuwait_active(&rq->hotplug_wait)) {
+                       raw_spin_unlock(&rq->lock);
+                       rcuwait_wake_up(&rq->hotplug_wait);
+                       raw_spin_lock(&rq->lock);
+               }
+               return;
+       }
 
+       get_task_struct(push_task);
        /*
-        * put_prev_task() and pick_next_task() sched
-        * class method both need to have an up-to-date
-        * value of rq->clock[_task]
+        * Temporarily drop rq->lock such that we can wake-up the stop task.
+        * Both preemption and IRQs are still disabled.
         */
-       update_rq_clock(rq);
+       raw_spin_unlock(&rq->lock);
+       stop_one_cpu_nowait(rq->cpu, __balance_push_cpu_stop, push_task,
+                           this_cpu_ptr(&push_work));
+       /*
+        * At this point need_resched() is true and we'll take the loop in
+        * schedule(). The next pick is obviously going to be the stop task
+        * which is_per_cpu_kthread() and will push this task away.
+        */
+       raw_spin_lock(&rq->lock);
+}
 
-       for (;;) {
-               /*
-                * There's this thread running, bail when that's the only
-                * remaining thread:
-                */
-               if (rq->nr_running == 1)
-                       break;
+static void balance_push_set(int cpu, bool on)
+{
+       struct rq *rq = cpu_rq(cpu);
+       struct rq_flags rf;
 
-               next = __pick_migrate_task(rq);
+       rq_lock_irqsave(rq, &rf);
+       if (on)
+               rq->balance_flags |= BALANCE_PUSH;
+       else
+               rq->balance_flags &= ~BALANCE_PUSH;
+       rq_unlock_irqrestore(rq, &rf);
+}
 
-               /*
-                * Rules for changing task_struct::cpus_mask are holding
-                * both pi_lock and rq->lock, such that holding either
-                * stabilizes the mask.
-                *
-                * Drop rq->lock is not quite as disastrous as it usually is
-                * because !cpu_active at this point, which means load-balance
-                * will not interfere. Also, stop-machine.
-                */
-               rq_unlock(rq, rf);
-               raw_spin_lock(&next->pi_lock);
-               rq_relock(rq, rf);
+/*
+ * Invoked from a CPUs hotplug control thread after the CPU has been marked
+ * inactive. All tasks which are not per CPU kernel threads are either
+ * pushed off this CPU now via balance_push() or placed on a different CPU
+ * during wakeup. Wait until the CPU is quiescent.
+ */
+static void balance_hotplug_wait(void)
+{
+       struct rq *rq = this_rq();
 
-               /*
-                * Since we're inside stop-machine, _nothing_ should have
-                * changed the task, WARN if weird stuff happened, because in
-                * that case the above rq->lock drop is a fail too.
-                */
-               if (WARN_ON(task_rq(next) != rq || !task_on_rq_queued(next))) {
-                       raw_spin_unlock(&next->pi_lock);
-                       continue;
-               }
+       rcuwait_wait_event(&rq->hotplug_wait,
+                          rq->nr_running == 1 && !rq_has_pinned_tasks(rq),
+                          TASK_UNINTERRUPTIBLE);
+}
 
-               /* Find suitable destination for @next, with force if needed. */
-               dest_cpu = select_fallback_rq(dead_rq->cpu, next);
-               rq = __migrate_task(rq, rf, next, dest_cpu);
-               if (rq != dead_rq) {
-                       rq_unlock(rq, rf);
-                       rq = dead_rq;
-                       *rf = orf;
-                       rq_relock(rq, rf);
-               }
-               raw_spin_unlock(&next->pi_lock);
-       }
+#else
+
+static inline void balance_push(struct rq *rq)
+{
+}
 
-       rq->stop = stop;
+static inline void balance_push_set(int cpu, bool on)
+{
+}
+
+static inline void balance_hotplug_wait(void)
+{
 }
+
 #endif /* CONFIG_HOTPLUG_CPU */
 
 void set_rq_online(struct rq *rq)
@@ -6882,6 +7572,8 @@ int sched_cpu_activate(unsigned int cpu)
        struct rq *rq = cpu_rq(cpu);
        struct rq_flags rf;
 
+       balance_push_set(cpu, false);
+
 #ifdef CONFIG_SCHED_SMT
        /*
         * When going up, increment the number of cores with SMT present.
@@ -6917,6 +7609,8 @@ int sched_cpu_activate(unsigned int cpu)
 
 int sched_cpu_deactivate(unsigned int cpu)
 {
+       struct rq *rq = cpu_rq(cpu);
+       struct rq_flags rf;
        int ret;
 
        set_cpu_active(cpu, false);
@@ -6929,6 +7623,16 @@ int sched_cpu_deactivate(unsigned int cpu)
         */
        synchronize_rcu();
 
+       balance_push_set(cpu, true);
+
+       rq_lock_irqsave(rq, &rf);
+       if (rq->rd) {
+               update_rq_clock(rq);
+               BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span));
+               set_rq_offline(rq);
+       }
+       rq_unlock_irqrestore(rq, &rf);
+
 #ifdef CONFIG_SCHED_SMT
        /*
         * When going down, decrement the number of cores with SMT present.
@@ -6942,6 +7646,7 @@ int sched_cpu_deactivate(unsigned int cpu)
 
        ret = cpuset_cpu_inactive(cpu);
        if (ret) {
+               balance_push_set(cpu, false);
                set_cpu_active(cpu, true);
                return ret;
        }
@@ -6965,6 +7670,41 @@ int sched_cpu_starting(unsigned int cpu)
 }
 
 #ifdef CONFIG_HOTPLUG_CPU
+
+/*
+ * Invoked immediately before the stopper thread is invoked to bring the
+ * CPU down completely. At this point all per CPU kthreads except the
+ * hotplug thread (current) and the stopper thread (inactive) have been
+ * either parked or have been unbound from the outgoing CPU. Ensure that
+ * any of those which might be on the way out are gone.
+ *
+ * If after this point a bound task is being woken on this CPU then the
+ * responsible hotplug callback has failed to do it's job.
+ * sched_cpu_dying() will catch it with the appropriate fireworks.
+ */
+int sched_cpu_wait_empty(unsigned int cpu)
+{
+       balance_hotplug_wait();
+       return 0;
+}
+
+/*
+ * Since this CPU is going 'away' for a while, fold any nr_active delta we
+ * might have. Called from the CPU stopper task after ensuring that the
+ * stopper is the last running task on the CPU, so nr_active count is
+ * stable. We need to take the teardown thread which is calling this into
+ * account, so we hand in adjust = 1 to the load calculation.
+ *
+ * Also see the comment "Global load-average calculations".
+ */
+static void calc_load_migrate(struct rq *rq)
+{
+       long delta = calc_load_fold_active(rq, 1);
+
+       if (delta)
+               atomic_long_add(delta, &calc_load_tasks);
+}
+
 int sched_cpu_dying(unsigned int cpu)
 {
        struct rq *rq = cpu_rq(cpu);
@@ -6974,12 +7714,7 @@ int sched_cpu_dying(unsigned int cpu)
        sched_tick_stop(cpu);
 
        rq_lock_irqsave(rq, &rf);
-       if (rq->rd) {
-               BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span));
-               set_rq_offline(rq);
-       }
-       migrate_tasks(rq, &rf);
-       BUG_ON(rq->nr_running != 1);
+       BUG_ON(rq->nr_running != 1 || rq_has_pinned_tasks(rq));
        rq_unlock_irqrestore(rq, &rf);
 
        calc_load_migrate(rq);
@@ -7186,6 +7921,9 @@ void __init sched_init(void)
 
                rq_csd_init(rq, &rq->nohz_csd, nohz_csd_func);
 #endif
+#ifdef CONFIG_HOTPLUG_CPU
+               rcuwait_init(&rq->hotplug_wait);
+#endif
 #endif /* CONFIG_SMP */
                hrtick_rq_init(rq);
                atomic_set(&rq->nr_iowait, 0);
@@ -7226,7 +7964,7 @@ 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);
 }
@@ -7323,6 +8061,39 @@ void __cant_sleep(const char *file, int line, int preempt_offset)
        add_taint(TAINT_WARN, LOCKDEP_STILL_OK);
 }
 EXPORT_SYMBOL_GPL(__cant_sleep);
+
+#ifdef CONFIG_SMP
+void __cant_migrate(const char *file, int line)
+{
+       static unsigned long prev_jiffy;
+
+       if (irqs_disabled())
+               return;
+
+       if (is_migration_disabled(current))
+               return;
+
+       if (!IS_ENABLED(CONFIG_PREEMPT_COUNT))
+               return;
+
+       if (preempt_count() > 0)
+               return;
+
+       if (time_before(jiffies, prev_jiffy + HZ) && prev_jiffy)
+               return;
+       prev_jiffy = jiffies;
+
+       pr_err("BUG: assuming non migratable context at %s:%d\n", file, line);
+       pr_err("in_atomic(): %d, irqs_disabled(): %d, migration_disabled() %u pid: %d, name: %s\n",
+              in_atomic(), irqs_disabled(), is_migration_disabled(current),
+              current->pid, current->comm);
+
+       debug_show_held_locks(current);
+       dump_stack();
+       add_taint(TAINT_WARN, LOCKDEP_STILL_OK);
+}
+EXPORT_SYMBOL_GPL(__cant_migrate);
+#endif
 #endif
 
 #ifdef CONFIG_MAGIC_SYSRQ
index 8cb06c8..ceb03d7 100644 (file)
@@ -120,7 +120,7 @@ int cpudl_find(struct cpudl *cp, struct task_struct *p,
        const struct sched_dl_entity *dl_se = &p->dl;
 
        if (later_mask &&
-           cpumask_and(later_mask, cp->free_cpus, p->cpus_ptr)) {
+           cpumask_and(later_mask, cp->free_cpus, &p->cpus_mask)) {
                unsigned long cap, max_cap = 0;
                int cpu, max_cpu = -1;
 
@@ -151,7 +151,7 @@ int cpudl_find(struct cpudl *cp, struct task_struct *p,
 
                WARN_ON(best_cpu != -1 && !cpu_present(best_cpu));
 
-               if (cpumask_test_cpu(best_cpu, p->cpus_ptr) &&
+               if (cpumask_test_cpu(best_cpu, &p->cpus_mask) &&
                    dl_time_before(dl_se->deadline, cp->elements[0].dl)) {
                        if (later_mask)
                                cpumask_set_cpu(best_cpu, later_mask);
index 0033731..11c4df2 100644 (file)
@@ -73,11 +73,11 @@ static inline int __cpupri_find(struct cpupri *cp, struct task_struct *p,
        if (skip)
                return 0;
 
-       if (cpumask_any_and(p->cpus_ptr, vec->mask) >= nr_cpu_ids)
+       if (cpumask_any_and(&p->cpus_mask, vec->mask) >= nr_cpu_ids)
                return 0;
 
        if (lowest_mask) {
-               cpumask_and(lowest_mask, p->cpus_ptr, vec->mask);
+               cpumask_and(lowest_mask, &p->cpus_mask, vec->mask);
 
                /*
                 * We have to ensure that we have at least one bit
index ca0eef7..02a5aa6 100644 (file)
@@ -44,12 +44,13 @@ static void irqtime_account_delta(struct irqtime *irqtime, u64 delta,
 }
 
 /*
- * Called before incrementing preempt_count on {soft,}irq_enter
+ * Called after incrementing preempt_count on {soft,}irq_enter
  * and before decrementing preempt_count on {soft,}irq_exit.
  */
-void irqtime_account_irq(struct task_struct *curr)
+void irqtime_account_irq(struct task_struct *curr, unsigned int offset)
 {
        struct irqtime *irqtime = this_cpu_ptr(&cpu_irqtime);
+       unsigned int pc;
        s64 delta;
        int cpu;
 
@@ -59,6 +60,7 @@ void irqtime_account_irq(struct task_struct *curr)
        cpu = smp_processor_id();
        delta = sched_clock_cpu(cpu) - irqtime->irq_start_time;
        irqtime->irq_start_time += delta;
+       pc = irq_count() - offset;
 
        /*
         * We do not account for softirq time from ksoftirqd here.
@@ -66,12 +68,11 @@ void irqtime_account_irq(struct task_struct *curr)
         * in that case, so as not to confuse scheduler with a special task
         * that do not consume any time, but still wants to run.
         */
-       if (hardirq_count())
+       if (pc & HARDIRQ_MASK)
                irqtime_account_delta(irqtime, delta, CPUTIME_IRQ);
-       else if (in_serving_softirq() && curr != this_cpu_ksoftirqd())
+       else if ((pc & SOFTIRQ_OFFSET) && curr != this_cpu_ksoftirqd())
                irqtime_account_delta(irqtime, delta, CPUTIME_SOFTIRQ);
 }
-EXPORT_SYMBOL_GPL(irqtime_account_irq);
 
 static u64 irqtime_tick_accounted(u64 maxtime)
 {
@@ -418,24 +419,21 @@ void vtime_task_switch(struct task_struct *prev)
 }
 # endif
 
-/*
- * Archs that account the whole time spent in the idle task
- * (outside irq) as idle time can rely on this and just implement
- * vtime_account_kernel() and vtime_account_idle(). Archs that
- * have other meaning of the idle time (s390 only includes the
- * time spent by the CPU when it's in low power mode) must override
- * vtime_account().
- */
-#ifndef __ARCH_HAS_VTIME_ACCOUNT
-void vtime_account_irq_enter(struct task_struct *tsk)
+void vtime_account_irq(struct task_struct *tsk, unsigned int offset)
 {
-       if (!in_interrupt() && is_idle_task(tsk))
+       unsigned int pc = irq_count() - offset;
+
+       if (pc & HARDIRQ_OFFSET) {
+               vtime_account_hardirq(tsk);
+       } else if (pc & SOFTIRQ_OFFSET) {
+               vtime_account_softirq(tsk);
+       } else if (!IS_ENABLED(CONFIG_HAVE_VIRT_CPU_ACCOUNTING_IDLE) &&
+                  is_idle_task(tsk)) {
                vtime_account_idle(tsk);
-       else
+       } else {
                vtime_account_kernel(tsk);
+       }
 }
-EXPORT_SYMBOL_GPL(vtime_account_irq_enter);
-#endif /* __ARCH_HAS_VTIME_ACCOUNT */
 
 void cputime_adjust(struct task_cputime *curr, struct prev_cputime *prev,
                    u64 *ut, u64 *st)
index a3ae00c..d7e3adf 100644 (file)
@@ -565,7 +565,7 @@ static int push_dl_task(struct rq *rq);
 
 static inline bool need_pull_dl_task(struct rq *rq, struct task_struct *prev)
 {
-       return dl_task(prev);
+       return rq->online && dl_task(prev);
 }
 
 static DEFINE_PER_CPU(struct callback_head, dl_push_head);
@@ -1919,7 +1919,7 @@ static void task_fork_dl(struct task_struct *p)
 static int pick_dl_task(struct rq *rq, struct task_struct *p, int cpu)
 {
        if (!task_running(rq, p) &&
-           cpumask_test_cpu(cpu, p->cpus_ptr))
+           cpumask_test_cpu(cpu, &p->cpus_mask))
                return 1;
        return 0;
 }
@@ -2009,8 +2009,8 @@ static int find_later_rq(struct task_struct *task)
                                return this_cpu;
                        }
 
-                       best_cpu = cpumask_first_and(later_mask,
-                                                       sched_domain_span(sd));
+                       best_cpu = cpumask_any_and_distribute(later_mask,
+                                                             sched_domain_span(sd));
                        /*
                         * Last chance: if a CPU being in both later_mask
                         * and current sd span is valid, that becomes our
@@ -2032,7 +2032,7 @@ static int find_later_rq(struct task_struct *task)
        if (this_cpu != -1)
                return this_cpu;
 
-       cpu = cpumask_any(later_mask);
+       cpu = cpumask_any_distribute(later_mask);
        if (cpu < nr_cpu_ids)
                return cpu;
 
@@ -2069,7 +2069,7 @@ static struct rq *find_lock_later_rq(struct task_struct *task, struct rq *rq)
                /* Retry if something changed. */
                if (double_lock_balance(rq, later_rq)) {
                        if (unlikely(task_rq(task) != rq ||
-                                    !cpumask_test_cpu(later_rq->cpu, task->cpus_ptr) ||
+                                    !cpumask_test_cpu(later_rq->cpu, &task->cpus_mask) ||
                                     task_running(rq, task) ||
                                     !dl_task(task) ||
                                     !task_on_rq_queued(task))) {
@@ -2136,6 +2136,9 @@ static int push_dl_task(struct rq *rq)
                return 0;
 
 retry:
+       if (is_migration_disabled(next_task))
+               return 0;
+
        if (WARN_ON(next_task == rq->curr))
                return 0;
 
@@ -2213,7 +2216,7 @@ static void push_dl_tasks(struct rq *rq)
 static void pull_dl_task(struct rq *this_rq)
 {
        int this_cpu = this_rq->cpu, cpu;
-       struct task_struct *p;
+       struct task_struct *p, *push_task;
        bool resched = false;
        struct rq *src_rq;
        u64 dmin = LONG_MAX;
@@ -2243,6 +2246,7 @@ static void pull_dl_task(struct rq *this_rq)
                        continue;
 
                /* Might drop this_rq->lock */
+               push_task = NULL;
                double_lock_balance(this_rq, src_rq);
 
                /*
@@ -2274,17 +2278,28 @@ static void pull_dl_task(struct rq *this_rq)
                                           src_rq->curr->dl.deadline))
                                goto skip;
 
-                       resched = true;
-
-                       deactivate_task(src_rq, p, 0);
-                       set_task_cpu(p, this_cpu);
-                       activate_task(this_rq, p, 0);
-                       dmin = p->dl.deadline;
+                       if (is_migration_disabled(p)) {
+                               trace_sched_migrate_pull_tp(p);
+                               push_task = get_push_task(src_rq);
+                       } else {
+                               deactivate_task(src_rq, p, 0);
+                               set_task_cpu(p, this_cpu);
+                               activate_task(this_rq, p, 0);
+                               dmin = p->dl.deadline;
+                               resched = true;
+                       }
 
                        /* Is there any other task even earlier? */
                }
 skip:
                double_unlock_balance(this_rq, src_rq);
+
+               if (push_task) {
+                       raw_spin_unlock(&this_rq->lock);
+                       stop_one_cpu_nowait(src_rq->cpu, push_cpu_stop,
+                                           push_task, &src_rq->push_work);
+                       raw_spin_lock(&this_rq->lock);
+               }
        }
 
        if (resched)
@@ -2308,7 +2323,8 @@ static void task_woken_dl(struct rq *rq, struct task_struct *p)
 }
 
 static void set_cpus_allowed_dl(struct task_struct *p,
-                               const struct cpumask *new_mask)
+                               const struct cpumask *new_mask,
+                               u32 flags)
 {
        struct root_domain *src_rd;
        struct rq *rq;
@@ -2337,7 +2353,7 @@ static void set_cpus_allowed_dl(struct task_struct *p,
                raw_spin_unlock(&src_dl_b->lock);
        }
 
-       set_cpus_allowed_common(p, new_mask);
+       set_cpus_allowed_common(p, new_mask, flags);
 }
 
 /* Assumes rq->lock is held */
@@ -2532,6 +2548,7 @@ const struct sched_class dl_sched_class
        .rq_online              = rq_online_dl,
        .rq_offline             = rq_offline_dl,
        .task_woken             = task_woken_dl,
+       .find_lock_rq           = find_lock_later_rq,
 #endif
 
        .task_tick              = task_tick_dl,
index 8d2f238..d18733a 100644 (file)
@@ -4397,7 +4397,7 @@ 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.
@@ -4421,7 +4421,7 @@ 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
@@ -4564,7 +4564,7 @@ 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;
        }
        /*
@@ -4701,7 +4701,7 @@ 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
@@ -5436,7 +5436,7 @@ 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);
@@ -7019,7 +7019,7 @@ 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
@@ -10779,7 +10779,7 @@ 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;
@@ -10806,7 +10806,7 @@ 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 f1bf5e1..bc2466a 100644 (file)
@@ -45,11 +45,19 @@ SCHED_FEAT(DOUBLE_TICK, false)
  */
 SCHED_FEAT(NONTASK_CAPACITY, true)
 
+#ifdef CONFIG_PREEMPT_RT
+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 41b14d9..bdba3e2 100644 (file)
@@ -270,7 +270,7 @@ static void pull_rt_task(struct rq *this_rq);
 static inline bool need_pull_rt_task(struct rq *rq, struct task_struct *prev)
 {
        /* Try to pull RT tasks here if we lower this rq's prio */
-       return rq->rt.highest_prio.curr > prev->prio;
+       return rq->online && rq->rt.highest_prio.curr > prev->prio;
 }
 
 static inline int rt_overloaded(struct rq *rq)
@@ -1667,7 +1667,7 @@ static void put_prev_task_rt(struct rq *rq, struct task_struct *p)
 static int pick_rt_task(struct rq *rq, struct task_struct *p, int cpu)
 {
        if (!task_running(rq, p) &&
-           cpumask_test_cpu(cpu, p->cpus_ptr))
+           cpumask_test_cpu(cpu, &p->cpus_mask))
                return 1;
 
        return 0;
@@ -1761,8 +1761,8 @@ static int find_lowest_rq(struct task_struct *task)
                                return this_cpu;
                        }
 
-                       best_cpu = cpumask_first_and(lowest_mask,
-                                                    sched_domain_span(sd));
+                       best_cpu = cpumask_any_and_distribute(lowest_mask,
+                                                             sched_domain_span(sd));
                        if (best_cpu < nr_cpu_ids) {
                                rcu_read_unlock();
                                return best_cpu;
@@ -1779,7 +1779,7 @@ static int find_lowest_rq(struct task_struct *task)
        if (this_cpu != -1)
                return this_cpu;
 
-       cpu = cpumask_any(lowest_mask);
+       cpu = cpumask_any_distribute(lowest_mask);
        if (cpu < nr_cpu_ids)
                return cpu;
 
@@ -1820,7 +1820,7 @@ static struct rq *find_lock_lowest_rq(struct task_struct *task, struct rq *rq)
                         * Also make sure that it wasn't scheduled on its rq.
                         */
                        if (unlikely(task_rq(task) != rq ||
-                                    !cpumask_test_cpu(lowest_rq->cpu, task->cpus_ptr) ||
+                                    !cpumask_test_cpu(lowest_rq->cpu, &task->cpus_mask) ||
                                     task_running(rq, task) ||
                                     !rt_task(task) ||
                                     !task_on_rq_queued(task))) {
@@ -1868,7 +1868,7 @@ static struct task_struct *pick_next_pushable_task(struct rq *rq)
  * running task can migrate over to a CPU that is running a task
  * of lesser priority.
  */
-static int push_rt_task(struct rq *rq)
+static int push_rt_task(struct rq *rq, bool pull)
 {
        struct task_struct *next_task;
        struct rq *lowest_rq;
@@ -1882,6 +1882,39 @@ static int push_rt_task(struct rq *rq)
                return 0;
 
 retry:
+       if (is_migration_disabled(next_task)) {
+               struct task_struct *push_task = NULL;
+               int cpu;
+
+               if (!pull)
+                       return 0;
+
+               trace_sched_migrate_pull_tp(next_task);
+
+               if (rq->push_busy)
+                       return 0;
+
+               cpu = find_lowest_rq(rq->curr);
+               if (cpu == -1 || cpu == rq->cpu)
+                       return 0;
+
+               /*
+                * Given we found a CPU with lower priority than @next_task,
+                * therefore it should be running. However we cannot migrate it
+                * to this other CPU, instead attempt to push the current
+                * running task on this CPU away.
+                */
+               push_task = get_push_task(rq);
+               if (push_task) {
+                       raw_spin_unlock(&rq->lock);
+                       stop_one_cpu_nowait(rq->cpu, push_cpu_stop,
+                                           push_task, &rq->push_work);
+                       raw_spin_lock(&rq->lock);
+               }
+
+               return 0;
+       }
+
        if (WARN_ON(next_task == rq->curr))
                return 0;
 
@@ -1936,12 +1969,10 @@ retry:
        deactivate_task(rq, next_task, 0);
        set_task_cpu(next_task, lowest_rq->cpu);
        activate_task(lowest_rq, next_task, 0);
-       ret = 1;
-
        resched_curr(lowest_rq);
+       ret = 1;
 
        double_unlock_balance(rq, lowest_rq);
-
 out:
        put_task_struct(next_task);
 
@@ -1951,7 +1982,7 @@ out:
 static void push_rt_tasks(struct rq *rq)
 {
        /* push_rt_task will return true if it moved an RT */
-       while (push_rt_task(rq))
+       while (push_rt_task(rq, false))
                ;
 }
 
@@ -2104,7 +2135,8 @@ void rto_push_irq_work_func(struct irq_work *work)
         */
        if (has_pushable_tasks(rq)) {
                raw_spin_lock(&rq->lock);
-               push_rt_tasks(rq);
+               while (push_rt_task(rq, true))
+                       ;
                raw_spin_unlock(&rq->lock);
        }
 
@@ -2129,7 +2161,7 @@ static void pull_rt_task(struct rq *this_rq)
 {
        int this_cpu = this_rq->cpu, cpu;
        bool resched = false;
-       struct task_struct *p;
+       struct task_struct *p, *push_task;
        struct rq *src_rq;
        int rt_overload_count = rt_overloaded(this_rq);
 
@@ -2176,6 +2208,7 @@ static void pull_rt_task(struct rq *this_rq)
                 * double_lock_balance, and another CPU could
                 * alter this_rq
                 */
+               push_task = NULL;
                double_lock_balance(this_rq, src_rq);
 
                /*
@@ -2203,11 +2236,15 @@ static void pull_rt_task(struct rq *this_rq)
                        if (p->prio < src_rq->curr->prio)
                                goto skip;
 
-                       resched = true;
-
-                       deactivate_task(src_rq, p, 0);
-                       set_task_cpu(p, this_cpu);
-                       activate_task(this_rq, p, 0);
+                       if (is_migration_disabled(p)) {
+                               trace_sched_migrate_pull_tp(p);
+                               push_task = get_push_task(src_rq);
+                       } else {
+                               deactivate_task(src_rq, p, 0);
+                               set_task_cpu(p, this_cpu);
+                               activate_task(this_rq, p, 0);
+                               resched = true;
+                       }
                        /*
                         * We continue with the search, just in
                         * case there's an even higher prio task
@@ -2217,6 +2254,13 @@ static void pull_rt_task(struct rq *this_rq)
                }
 skip:
                double_unlock_balance(this_rq, src_rq);
+
+               if (push_task) {
+                       raw_spin_unlock(&this_rq->lock);
+                       stop_one_cpu_nowait(src_rq->cpu, push_cpu_stop,
+                                           push_task, &src_rq->push_work);
+                       raw_spin_lock(&this_rq->lock);
+               }
        }
 
        if (resched)
@@ -2465,6 +2509,7 @@ const struct sched_class rt_sched_class
        .rq_offline             = rq_offline_rt,
        .task_woken             = task_woken_rt,
        .switched_from          = switched_from_rt,
+       .find_lock_rq           = find_lock_lowest_rq,
 #endif
 
        .task_tick              = task_tick_rt,
index 08db8e0..c2c9c38 100644 (file)
@@ -976,6 +976,7 @@ struct rq {
        unsigned long           cpu_capacity_orig;
 
        struct callback_head    *balance_callback;
+       unsigned char           balance_flags;
 
        unsigned char           nohz_idle_balance;
        unsigned char           idle_balance;
@@ -1006,6 +1007,10 @@ struct rq {
 
        /* This is used to determine avg_idle's max value */
        u64                     max_idle_balance_cost;
+
+#ifdef CONFIG_HOTPLUG_CPU
+       struct rcuwait          hotplug_wait;
+#endif
 #endif /* CONFIG_SMP */
 
 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
@@ -1052,6 +1057,12 @@ struct rq {
        /* Must be inspected within a rcu lock section */
        struct cpuidle_state    *idle_state;
 #endif
+
+#ifdef CONFIG_SMP
+       unsigned int            nr_pinned;
+#endif
+       unsigned int            push_busy;
+       struct cpu_stop_work    push_work;
 };
 
 #ifdef CONFIG_FAIR_GROUP_SCHED
@@ -1079,6 +1090,16 @@ static inline int cpu_of(struct rq *rq)
 #endif
 }
 
+#define MDF_PUSH       0x01
+
+static inline bool is_migration_disabled(struct task_struct *p)
+{
+#ifdef CONFIG_SMP
+       return p->migration_disabled;
+#else
+       return false;
+#endif
+}
 
 #ifdef CONFIG_SCHED_SMT
 extern void __update_idle_core(struct rq *rq);
@@ -1225,6 +1246,9 @@ static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
        rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
        rf->clock_update_flags = 0;
 #endif
+#ifdef CONFIG_SMP
+       SCHED_WARN_ON(rq->balance_callback);
+#endif
 }
 
 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
@@ -1386,6 +1410,9 @@ init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
 
 #ifdef CONFIG_SMP
 
+#define BALANCE_WORK   0x01
+#define BALANCE_PUSH   0x02
+
 static inline void
 queue_balance_callback(struct rq *rq,
                       struct callback_head *head,
@@ -1393,12 +1420,13 @@ queue_balance_callback(struct rq *rq,
 {
        lockdep_assert_held(&rq->lock);
 
-       if (unlikely(head->next))
+       if (unlikely(head->next || (rq->balance_flags & BALANCE_PUSH)))
                return;
 
        head->func = (void (*)(struct callback_head *))func;
        head->next = rq->balance_callback;
        rq->balance_callback = head;
+       rq->balance_flags |= BALANCE_WORK;
 }
 
 #define rcu_dereference_check_sched_domain(p) \
@@ -1725,6 +1753,7 @@ static inline int task_on_rq_migrating(struct task_struct *p)
 #define WF_FORK                        0x02            /* Child wakeup after fork */
 #define WF_MIGRATED            0x04            /* Internal use, task got migrated */
 #define WF_ON_CPU              0x08            /* Wakee is on_cpu */
+#define WF_LOCK_SLEEPER                0x10            /* Wakeup spinlock "sleeper" */
 
 /*
  * To aid in avoiding the subversion of "niceness" due to uneven distribution
@@ -1806,10 +1835,13 @@ struct sched_class {
        void (*task_woken)(struct rq *this_rq, struct task_struct *task);
 
        void (*set_cpus_allowed)(struct task_struct *p,
-                                const struct cpumask *newmask);
+                                const struct cpumask *newmask,
+                                u32 flags);
 
        void (*rq_online)(struct rq *rq);
        void (*rq_offline)(struct rq *rq);
+
+       struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq);
 #endif
 
        void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
@@ -1893,13 +1925,38 @@ static inline bool sched_fair_runnable(struct rq *rq)
 extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
 extern struct task_struct *pick_next_task_idle(struct rq *rq);
 
+#define SCA_CHECK              0x01
+#define SCA_MIGRATE_DISABLE    0x02
+#define SCA_MIGRATE_ENABLE     0x04
+
 #ifdef CONFIG_SMP
 
 extern void update_group_capacity(struct sched_domain *sd, int cpu);
 
 extern void trigger_load_balance(struct rq *rq);
 
-extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask);
+extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask, u32 flags);
+
+static inline struct task_struct *get_push_task(struct rq *rq)
+{
+       struct task_struct *p = rq->curr;
+
+       lockdep_assert_held(&rq->lock);
+
+       if (rq->push_busy)
+               return NULL;
+
+       if (p->nr_cpus_allowed == 1)
+               return NULL;
+
+       if (p->migration_disabled)
+               return NULL;
+
+       rq->push_busy = true;
+       return get_task_struct(p);
+}
+
+extern int push_cpu_stop(void *arg);
 
 #endif
 
@@ -1943,6 +2000,15 @@ extern void reweight_task(struct task_struct *p, int prio);
 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 e1c655f..f230b1a 100644 (file)
@@ -64,6 +64,7 @@ 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)) {
index dd77702..c2d1d1e 100644 (file)
@@ -514,6 +514,7 @@ 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);
+       atomic_or(IRQ_WORK_HARD_IRQ, &rd->rto_push_work.flags);
 #endif
 
        init_dl_bw(&rd->dl_bw);
index 6bb2df4..16f9014 100644 (file)
@@ -20,6 +20,7 @@
 #include <linux/sched/task.h>
 #include <linux/sched/task_stack.h>
 #include <linux/sched/cputime.h>
+#include <linux/sched/rt.h>
 #include <linux/file.h>
 #include <linux/fs.h>
 #include <linux/proc_fs.h>
@@ -404,13 +405,30 @@ void task_join_group_stop(struct task_struct *task)
        task_set_jobctl_pending(task, mask | JOBCTL_STOP_PENDING);
 }
 
+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;
@@ -432,7 +450,10 @@ __sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimi
        rcu_read_unlock();
 
        if (override_rlimit || likely(sigpending <= task_rlimit(t, RLIMIT_SIGPENDING))) {
-               q = kmem_cache_alloc(sigqueue_cachep, flags);
+               if (!fromslab)
+                       q = get_task_cache(t);
+               if (!q)
+                       q = kmem_cache_alloc(sigqueue_cachep, flags);
        } else {
                print_dropped_signal(sig);
        }
@@ -449,6 +470,13 @@ __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)
@@ -458,6 +486,21 @@ 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)) {
+               if (atomic_dec_and_test(&up->sigpending))
+                       free_uid(up);
+       } else
+                 __sigqueue_free(q);
+}
+
 void flush_sigqueue(struct sigpending *queue)
 {
        struct sigqueue *q;
@@ -471,6 +514,21 @@ 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)
@@ -594,7 +652,7 @@ 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
@@ -631,6 +689,8 @@ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, kernel_siginfo_t *in
        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
         */
@@ -1314,6 +1374,34 @@ force_sig_info_to_task(struct kernel_siginfo *info, struct task_struct *t)
        struct k_sigaction *action;
        int sig = info->si_signo;
 
+       /*
+        * 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()) {
+               struct task_struct *t = current;
+
+               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 = info->si_signo;
+                       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
        spin_lock_irqsave(&t->sighand->siglock, flags);
        action = &t->sighand->action[sig-1];
        ignored = action->sa.sa_handler == SIG_IGN;
@@ -1807,7 +1895,8 @@ 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;
@@ -2193,16 +2282,8 @@ static void ptrace_stop(int exit_code, int why, int clear_code, kernel_siginfo_t
                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);
                cgroup_enter_frozen();
-               preempt_enable_no_resched();
                freezable_schedule();
                cgroup_leave_frozen(true);
        } else {
index f73a597..244462d 100644 (file)
@@ -450,8 +450,18 @@ void flush_smp_call_function_from_idle(void)
 
        local_irq_save(flags);
        flush_smp_call_function_queue(true);
-       if (local_softirq_pending())
-               do_softirq();
+
+       if (local_softirq_pending()) {
+
+               if (!IS_ENABLED(CONFIG_PREEMPT_RT)) {
+                       do_softirq();
+               } else {
+                       struct task_struct *ksoftirqd = this_cpu_ksoftirqd();
+
+                       if (ksoftirqd && ksoftirqd->state != TASK_RUNNING)
+                               wake_up_process(ksoftirqd);
+               }
+       }
 
        local_irq_restore(flags);
 }
index 09229ad..c9adc5c 100644 (file)
@@ -13,6 +13,7 @@
 #include <linux/kernel_stat.h>
 #include <linux/interrupt.h>
 #include <linux/init.h>
+#include <linux/local_lock.h>
 #include <linux/mm.h>
 #include <linux/notifier.h>
 #include <linux/percpu.h>
@@ -25,6 +26,7 @@
 #include <linux/smpboot.h>
 #include <linux/tick.h>
 #include <linux/irq.h>
+#include <linux/wait_bit.h>
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/irq.h>
@@ -92,27 +94,212 @@ static bool ksoftirqd_running(unsigned long pending)
                !__kthread_should_park(tsk);
 }
 
+#ifdef CONFIG_TRACE_IRQFLAGS
+DEFINE_PER_CPU(int, hardirqs_enabled);
+DEFINE_PER_CPU(int, hardirq_context);
+EXPORT_PER_CPU_SYMBOL_GPL(hardirqs_enabled);
+EXPORT_PER_CPU_SYMBOL_GPL(hardirq_context);
+#endif
+
 /*
- * preempt_count and SOFTIRQ_OFFSET usage:
- * - preempt_count is changed by SOFTIRQ_OFFSET on entering or leaving
- *   softirq processing.
- * - preempt_count is changed by SOFTIRQ_DISABLE_OFFSET (= 2 * SOFTIRQ_OFFSET)
+ * SOFTIRQ_OFFSET usage:
+ *
+ * On !RT kernels 'count' is the preempt counter, on RT kernels this applies
+ * to a per CPU counter and to task::softirqs_disabled_cnt.
+ *
+ * - count is changed by SOFTIRQ_OFFSET on entering or leaving softirq
+ *   processing.
+ *
+ * - count is changed by SOFTIRQ_DISABLE_OFFSET (= 2 * SOFTIRQ_OFFSET)
  *   on local_bh_disable or local_bh_enable.
+ *
  * This lets us distinguish between whether we are currently processing
  * softirq and whether we just have bh disabled.
  */
+#ifdef CONFIG_PREEMPT_RT
 
 /*
- * This one is for softirq.c-internal use,
- * where hardirqs are disabled legitimately:
+ * RT accounts for BH disabled sections in task::softirqs_disabled_cnt and
+ * also in per CPU softirq_ctrl::cnt. This is necessary to allow tasks in a
+ * softirq disabled section to be preempted.
+ *
+ * The per task counter is used for softirq_count(), in_softirq() and
+ * in_serving_softirqs() because these counts are only valid when the task
+ * holding softirq_ctrl::lock is running.
+ *
+ * The per CPU counter prevents pointless wakeups of ksoftirqd in case that
+ * the task which is in a softirq disabled section is preempted or blocks.
  */
-#ifdef CONFIG_TRACE_IRQFLAGS
+struct softirq_ctrl {
+       local_lock_t    lock;
+       int             cnt;
+};
 
-DEFINE_PER_CPU(int, hardirqs_enabled);
-DEFINE_PER_CPU(int, hardirq_context);
-EXPORT_PER_CPU_SYMBOL_GPL(hardirqs_enabled);
-EXPORT_PER_CPU_SYMBOL_GPL(hardirq_context);
+static DEFINE_PER_CPU(struct softirq_ctrl, softirq_ctrl) = {
+       .lock   = INIT_LOCAL_LOCK(softirq_ctrl.lock),
+};
+
+/**
+ * local_bh_blocked() - Check for idle whether BH processing is blocked
+ *
+ * Returns false if the per CPU softirq::cnt is 0 otherwise true.
+ *
+ * This is invoked from the idle task to guard against false positive
+ * softirq pending warnings, which would happen when the task which holds
+ * softirq_ctrl::lock was the only running task on the CPU and blocks on
+ * some other lock.
+ */
+bool local_bh_blocked(void)
+{
+       return __this_cpu_read(softirq_ctrl.cnt) != 0;
+}
+
+void __local_bh_disable_ip(unsigned long ip, unsigned int cnt)
+{
+       unsigned long flags;
+       int newcnt;
+
+       WARN_ON_ONCE(in_hardirq());
+
+       /* First entry of a task into a BH disabled section? */
+       if (!current->softirq_disable_cnt) {
+               if (preemptible()) {
+                       local_lock(&softirq_ctrl.lock);
+                       /* Required to meet the RCU bottomhalf requirements. */
+                       rcu_read_lock();
+               } else {
+                       DEBUG_LOCKS_WARN_ON(this_cpu_read(softirq_ctrl.cnt));
+               }
+       }
+
+       /*
+        * Track the per CPU softirq disabled state. On RT this is per CPU
+        * state to allow preemption of bottom half disabled sections.
+        */
+       newcnt = __this_cpu_add_return(softirq_ctrl.cnt, cnt);
+       /*
+        * Reflect the result in the task state to prevent recursion on the
+        * local lock and to make softirq_count() & al work.
+        */
+       current->softirq_disable_cnt = newcnt;
+
+       if (IS_ENABLED(CONFIG_TRACE_IRQFLAGS) && newcnt == cnt) {
+               raw_local_irq_save(flags);
+               lockdep_softirqs_off(ip);
+               raw_local_irq_restore(flags);
+       }
+}
+EXPORT_SYMBOL(__local_bh_disable_ip);
+
+static void __local_bh_enable(unsigned int cnt, bool unlock)
+{
+       unsigned long flags;
+       int newcnt;
+
+       DEBUG_LOCKS_WARN_ON(current->softirq_disable_cnt !=
+                           this_cpu_read(softirq_ctrl.cnt));
+
+       if (IS_ENABLED(CONFIG_TRACE_IRQFLAGS) && softirq_count() == cnt) {
+               raw_local_irq_save(flags);
+               lockdep_softirqs_on(_RET_IP_);
+               raw_local_irq_restore(flags);
+       }
+
+       newcnt = __this_cpu_sub_return(softirq_ctrl.cnt, cnt);
+       current->softirq_disable_cnt = newcnt;
+
+       if (!newcnt && unlock) {
+               rcu_read_unlock();
+               local_unlock(&softirq_ctrl.lock);
+       }
+}
+
+void __local_bh_enable_ip(unsigned long ip, unsigned int cnt)
+{
+       bool preempt_on = preemptible();
+       unsigned long flags;
+       u32 pending;
+       int curcnt;
+
+       WARN_ON_ONCE(in_irq());
+       lockdep_assert_irqs_enabled();
+
+       local_irq_save(flags);
+       curcnt = __this_cpu_read(softirq_ctrl.cnt);
+
+       /*
+        * If this is not reenabling soft interrupts, no point in trying to
+        * run pending ones.
+        */
+       if (curcnt != cnt)
+               goto out;
+
+       pending = local_softirq_pending();
+       if (!pending || ksoftirqd_running(pending))
+               goto out;
+
+       /*
+        * If this was called from non preemptible context, wake up the
+        * softirq daemon.
+        */
+       if (!preempt_on) {
+               wakeup_softirqd();
+               goto out;
+       }
+
+       /*
+        * Adjust softirq count to SOFTIRQ_OFFSET which makes
+        * in_serving_softirq() become true.
+        */
+       cnt = SOFTIRQ_OFFSET;
+       __local_bh_enable(cnt, false);
+       __do_softirq();
+
+out:
+       __local_bh_enable(cnt, preempt_on);
+       local_irq_restore(flags);
+}
+EXPORT_SYMBOL(__local_bh_enable_ip);
+
+/*
+ * Invoked from ksoftirqd_run() outside of the interrupt disabled section
+ * to acquire the per CPU local lock for reentrancy protection.
+ */
+static inline void ksoftirqd_run_begin(void)
+{
+       __local_bh_disable_ip(_RET_IP_, SOFTIRQ_OFFSET);
+       local_irq_disable();
+}
+
+/* Counterpart to ksoftirqd_run_begin() */
+static inline void ksoftirqd_run_end(void)
+{
+       __local_bh_enable(SOFTIRQ_OFFSET, true);
+       WARN_ON_ONCE(in_interrupt());
+       local_irq_enable();
+}
+
+static inline void softirq_handle_begin(void) { }
+static inline void softirq_handle_end(void) { }
 
+static inline bool should_wake_ksoftirqd(void)
+{
+       return !this_cpu_read(softirq_ctrl.cnt);
+}
+
+static inline void invoke_softirq(void)
+{
+       if (should_wake_ksoftirqd())
+               wakeup_softirqd();
+}
+
+#else /* CONFIG_PREEMPT_RT */
+
+/*
+ * This one is for softirq.c-internal use, where hardirqs are disabled
+ * legitimately:
+ */
+#ifdef CONFIG_TRACE_IRQFLAGS
 void __local_bh_disable_ip(unsigned long ip, unsigned int cnt)
 {
        unsigned long flags;
@@ -203,6 +390,78 @@ void __local_bh_enable_ip(unsigned long ip, unsigned int cnt)
 }
 EXPORT_SYMBOL(__local_bh_enable_ip);
 
+static inline void softirq_handle_begin(void)
+{
+       __local_bh_disable_ip(_RET_IP_, SOFTIRQ_OFFSET);
+}
+
+static inline void softirq_handle_end(void)
+{
+       __local_bh_enable(SOFTIRQ_OFFSET);
+       WARN_ON_ONCE(in_interrupt());
+}
+
+static inline void ksoftirqd_run_begin(void)
+{
+       local_irq_disable();
+}
+
+static inline void ksoftirqd_run_end(void)
+{
+       local_irq_enable();
+}
+
+static inline bool should_wake_ksoftirqd(void)
+{
+       return true;
+}
+
+static inline void invoke_softirq(void)
+{
+       if (ksoftirqd_running(local_softirq_pending()))
+               return;
+
+       if (!force_irqthreads) {
+#ifdef CONFIG_HAVE_IRQ_EXIT_ON_IRQ_STACK
+               /*
+                * We can safely execute softirq on the current stack if
+                * it is the irq stack, because it should be near empty
+                * at this stage.
+                */
+               __do_softirq();
+#else
+               /*
+                * Otherwise, irq_exit() is called on the task stack that can
+                * be potentially deep already. So call softirq in its own stack
+                * to prevent from any overrun.
+                */
+               do_softirq_own_stack();
+#endif
+       } else {
+               wakeup_softirqd();
+       }
+}
+
+asmlinkage __visible void do_softirq(void)
+{
+       __u32 pending;
+       unsigned long flags;
+
+       if (in_interrupt())
+               return;
+
+       local_irq_save(flags);
+
+       pending = local_softirq_pending();
+
+       if (pending && !ksoftirqd_running(pending))
+               do_softirq_own_stack();
+
+       local_irq_restore(flags);
+}
+
+#endif /* !CONFIG_PREEMPT_RT */
+
 /*
  * We restart softirq processing for at most MAX_SOFTIRQ_RESTART times,
  * but break the loop if need_resched() is set or after 2 ms.
@@ -270,10 +529,10 @@ asmlinkage __visible void __softirq_entry __do_softirq(void)
        current->flags &= ~PF_MEMALLOC;
 
        pending = local_softirq_pending();
-       account_irq_enter_time(current);
 
-       __local_bh_disable_ip(_RET_IP_, SOFTIRQ_OFFSET);
+       softirq_handle_begin();
        in_hardirq = lockdep_softirq_start();
+       account_softirq_enter(current);
 
 restart:
        /* Reset the pending bitmask before enabling irqs */
@@ -307,8 +566,10 @@ restart:
                pending >>= softirq_bit;
        }
 
-       if (__this_cpu_read(ksoftirqd) == current)
+       if (!IS_ENABLED(CONFIG_PREEMPT_RT) &&
+           __this_cpu_read(ksoftirqd) == current)
                rcu_softirq_qs();
+
        local_irq_disable();
 
        pending = local_softirq_pending();
@@ -320,46 +581,23 @@ restart:
                wakeup_softirqd();
        }
 
+       account_softirq_exit(current);
        lockdep_softirq_end(in_hardirq);
-       account_irq_exit_time(current);
-       __local_bh_enable(SOFTIRQ_OFFSET);
-       WARN_ON_ONCE(in_interrupt());
+       softirq_handle_end();
        current_restore_flags(old_flags, PF_MEMALLOC);
 }
 
-asmlinkage __visible void do_softirq(void)
-{
-       __u32 pending;
-       unsigned long flags;
-
-       if (in_interrupt())
-               return;
-
-       local_irq_save(flags);
-
-       pending = local_softirq_pending();
-
-       if (pending && !ksoftirqd_running(pending))
-               do_softirq_own_stack();
-
-       local_irq_restore(flags);
-}
-
 /**
  * irq_enter_rcu - Enter an interrupt context with RCU watching
  */
 void irq_enter_rcu(void)
 {
-       if (is_idle_task(current) && !in_interrupt()) {
-               /*
-                * Prevent raise_softirq from needlessly waking up ksoftirqd
-                * here, as softirq will be serviced on return from interrupt.
-                */
-               local_bh_disable();
+       __irq_enter_raw();
+
+       if (is_idle_task(current) && (irq_count() == HARDIRQ_OFFSET))
                tick_irq_enter();
-               _local_bh_enable();
-       }
-       __irq_enter();
+
+       account_hardirq_enter(current);
 }
 
 /**
@@ -371,32 +609,6 @@ void irq_enter(void)
        irq_enter_rcu();
 }
 
-static inline void invoke_softirq(void)
-{
-       if (ksoftirqd_running(local_softirq_pending()))
-               return;
-
-       if (!force_irqthreads) {
-#ifdef CONFIG_HAVE_IRQ_EXIT_ON_IRQ_STACK
-               /*
-                * We can safely execute softirq on the current stack if
-                * it is the irq stack, because it should be near empty
-                * at this stage.
-                */
-               __do_softirq();
-#else
-               /*
-                * Otherwise, irq_exit() is called on the task stack that can
-                * be potentially deep already. So call softirq in its own stack
-                * to prevent from any overrun.
-                */
-               do_softirq_own_stack();
-#endif
-       } else {
-               wakeup_softirqd();
-       }
-}
-
 static inline void tick_irq_exit(void)
 {
 #ifdef CONFIG_NO_HZ_COMMON
@@ -417,7 +629,7 @@ static inline void __irq_exit_rcu(void)
 #else
        lockdep_assert_irqs_disabled();
 #endif
-       account_irq_exit_time(current);
+       account_hardirq_exit(current);
        preempt_count_sub(HARDIRQ_OFFSET);
        if (!in_interrupt() && local_softirq_pending())
                invoke_softirq();
@@ -466,7 +678,7 @@ inline void raise_softirq_irqoff(unsigned int nr)
         * Otherwise we wake up ksoftirqd to make sure we
         * schedule the softirq soon.
         */
-       if (!in_interrupt())
+       if (!in_interrupt() && should_wake_ksoftirqd())
                wakeup_softirqd();
 }
 
@@ -532,6 +744,16 @@ void __tasklet_hi_schedule(struct tasklet_struct *t)
 }
 EXPORT_SYMBOL(__tasklet_hi_schedule);
 
+static inline bool tasklet_clear_sched(struct tasklet_struct *t)
+{
+       if (test_and_clear_bit(TASKLET_STATE_SCHED, &t->state)) {
+               wake_up_var(&t->state);
+               return true;
+       }
+
+       return false;
+}
+
 static void tasklet_action_common(struct softirq_action *a,
                                  struct tasklet_head *tl_head,
                                  unsigned int softirq_nr)
@@ -551,8 +773,7 @@ static void tasklet_action_common(struct softirq_action *a,
 
                if (tasklet_trylock(t)) {
                        if (!atomic_read(&t->count)) {
-                               if (!test_and_clear_bit(TASKLET_STATE_SCHED,
-                                                       &t->state))
+                               if (!tasklet_clear_sched(t))
                                        BUG();
                                if (t->use_callback)
                                        t->callback(t);
@@ -607,21 +828,62 @@ void tasklet_init(struct tasklet_struct *t,
 }
 EXPORT_SYMBOL(tasklet_init);
 
+#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT)
+/*
+ * Do not use in new code. Waiting for tasklets from atomic contexts is
+ * error prone and should be avoided.
+ */
+void tasklet_unlock_spin_wait(struct tasklet_struct *t)
+{
+       while (test_bit(TASKLET_STATE_RUN, &(t)->state)) {
+               if (IS_ENABLED(CONFIG_PREEMPT_RT)) {
+                       /*
+                        * Prevent a live lock when current preempted soft
+                        * interrupt processing or prevents ksoftirqd from
+                        * running. If the tasklet runs on a different CPU
+                        * then this has no effect other than doing the BH
+                        * disable/enable dance for nothing.
+                        */
+                       local_bh_disable();
+                       local_bh_enable();
+               } else {
+                       cpu_relax();
+               }
+       }
+}
+EXPORT_SYMBOL(tasklet_unlock_spin_wait);
+#endif
+
 void tasklet_kill(struct tasklet_struct *t)
 {
        if (in_interrupt())
                pr_notice("Attempt to kill tasklet from interrupt\n");
 
-       while (test_and_set_bit(TASKLET_STATE_SCHED, &t->state)) {
-               do {
-                       yield();
-               } while (test_bit(TASKLET_STATE_SCHED, &t->state));
-       }
+       while (test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
+               wait_var_event(&t->state, !test_bit(TASKLET_STATE_SCHED, &t->state));
+
        tasklet_unlock_wait(t);
-       clear_bit(TASKLET_STATE_SCHED, &t->state);
+       tasklet_clear_sched(t);
 }
 EXPORT_SYMBOL(tasklet_kill);
 
+#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT)
+void tasklet_unlock(struct tasklet_struct *t)
+{
+       smp_mb__before_atomic();
+       clear_bit(TASKLET_STATE_RUN, &t->state);
+       smp_mb__after_atomic();
+       wake_up_var(&t->state);
+}
+EXPORT_SYMBOL_GPL(tasklet_unlock);
+
+void tasklet_unlock_wait(struct tasklet_struct *t)
+{
+       wait_var_event(&t->state, !test_bit(TASKLET_STATE_RUN, &t->state));
+}
+EXPORT_SYMBOL_GPL(tasklet_unlock_wait);
+#endif
+
 void __init softirq_init(void)
 {
        int cpu;
@@ -644,18 +906,18 @@ static int ksoftirqd_should_run(unsigned int cpu)
 
 static void run_ksoftirqd(unsigned int cpu)
 {
-       local_irq_disable();
+       ksoftirqd_run_begin();
        if (local_softirq_pending()) {
                /*
                 * We can safely run softirq on inline stack, as we are not deep
                 * in the task stack here.
                 */
                __do_softirq();
-               local_irq_enable();
+               ksoftirqd_run_end();
                cond_resched();
                return;
        }
-       local_irq_enable();
+       ksoftirqd_run_end();
 }
 
 #ifdef CONFIG_HOTPLUG_CPU
index 890b79c..971d8ac 100644 (file)
@@ -42,11 +42,27 @@ struct cpu_stopper {
        struct list_head        works;          /* list of pending works */
 
        struct cpu_stop_work    stop_work;      /* for stop_cpus */
+       unsigned long           caller;
+       cpu_stop_fn_t           fn;
 };
 
 static DEFINE_PER_CPU(struct cpu_stopper, cpu_stopper);
 static bool stop_machine_initialized = false;
 
+void print_stop_info(const char *log_lvl, struct task_struct *task)
+{
+       /*
+        * If @task is a stopper task, it cannot migrate and task_cpu() is
+        * stable.
+        */
+       struct cpu_stopper *stopper = per_cpu_ptr(&cpu_stopper, task_cpu(task));
+
+       if (task != stopper->thread)
+               return;
+
+       printk("%sStopper: %pS <- %pS\n", log_lvl, stopper->fn, (void *)stopper->caller);
+}
+
 /* static data for stop_cpus */
 static DEFINE_MUTEX(stop_cpus_mutex);
 static bool stop_cpus_in_progress;
@@ -123,7 +139,7 @@ static bool cpu_stop_queue_work(unsigned int cpu, struct cpu_stop_work *work)
 int stop_one_cpu(unsigned int cpu, cpu_stop_fn_t fn, void *arg)
 {
        struct cpu_stop_done done;
-       struct cpu_stop_work work = { .fn = fn, .arg = arg, .done = &done };
+       struct cpu_stop_work work = { .fn = fn, .arg = arg, .done = &done, .caller = _RET_IP_ };
 
        cpu_stop_init_done(&done, 1);
        if (!cpu_stop_queue_work(cpu, &work))
@@ -331,7 +347,8 @@ int stop_two_cpus(unsigned int cpu1, unsigned int cpu2, cpu_stop_fn_t fn, void *
        work1 = work2 = (struct cpu_stop_work){
                .fn = multi_cpu_stop,
                .arg = &msdata,
-               .done = &done
+               .done = &done,
+               .caller = _RET_IP_,
        };
 
        cpu_stop_init_done(&done, 2);
@@ -367,7 +384,7 @@ int stop_two_cpus(unsigned int cpu1, unsigned int cpu2, cpu_stop_fn_t fn, void *
 bool stop_one_cpu_nowait(unsigned int cpu, cpu_stop_fn_t fn, void *arg,
                        struct cpu_stop_work *work_buf)
 {
-       *work_buf = (struct cpu_stop_work){ .fn = fn, .arg = arg, };
+       *work_buf = (struct cpu_stop_work){ .fn = fn, .arg = arg, .caller = _RET_IP_, };
        return cpu_stop_queue_work(cpu, work_buf);
 }
 
@@ -487,6 +504,8 @@ repeat:
                int ret;
 
                /* cpu stop callbacks must not sleep, make in_atomic() == T */
+               stopper->caller = work->caller;
+               stopper->fn = fn;
                preempt_count_inc();
                ret = fn(arg);
                if (done) {
@@ -495,6 +514,8 @@ repeat:
                        cpu_stop_signal_done(done);
                }
                preempt_count_dec();
+               stopper->fn = NULL;
+               stopper->caller = 0;
                WARN_ONCE(preempt_count(),
                          "cpu_stop: %ps(%p) leaked preempt count\n", fn, arg);
                goto repeat;
index 4ef9071..6eb4432 100644 (file)
@@ -2052,6 +2052,36 @@ SYSCALL_DEFINE2(nanosleep_time32, struct old_timespec32 __user *, rqtp,
 }
 #endif
 
+#ifdef CONFIG_PREEMPT_RT
+/*
+ * Sleep for 1 ms in hope whoever holds what we want will let it go.
+ */
+void cpu_chill(void)
+{
+       unsigned int freeze_flag = current->flags & PF_NOFREEZE;
+       struct task_struct *self = current;
+       ktime_t chill_time;
+
+       raw_spin_lock_irq(&self->pi_lock);
+       self->saved_state = self->state;
+       __set_current_state_no_track(TASK_UNINTERRUPTIBLE);
+       raw_spin_unlock_irq(&self->pi_lock);
+
+       chill_time = ktime_set(0, NSEC_PER_MSEC);
+
+       current->flags |= PF_NOFREEZE;
+       schedule_hrtimeout(&chill_time, HRTIMER_MODE_REL_HARD);
+       if (!freeze_flag)
+               current->flags &= ~PF_NOFREEZE;
+
+       raw_spin_lock_irq(&self->pi_lock);
+       __set_current_state_no_track(self->saved_state);
+       self->saved_state = TASK_RUNNING;
+       raw_spin_unlock_irq(&self->pi_lock);
+}
+EXPORT_SYMBOL(cpu_chill);
+#endif
+
 /*
  * Functions related to boot-time initialization:
  */
index e8d351b..3e3130a 100644 (file)
@@ -925,7 +925,7 @@ static bool can_stop_idle_tick(int cpu, struct tick_sched *ts)
        if (unlikely(local_softirq_pending())) {
                static int ratelimit;
 
-               if (ratelimit < 10 &&
+               if (ratelimit < 10 && !local_bh_blocked() &&
                    (local_softirq_pending() & SOFTIRQ_STOP_IDLE_MASK)) {
                        pr_warn("NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #%02x!!!\n",
                                (unsigned int) local_softirq_pending());
index a3ec21b..cd67ee6 100644 (file)
@@ -1287,7 +1287,7 @@ static void del_timer_wait_running(struct timer_list *timer)
        u32 tf;
 
        tf = READ_ONCE(timer->flags);
-       if (!(tf & TIMER_MIGRATING)) {
+       if (!(tf & (TIMER_MIGRATING | TIMER_IRQSAFE))) {
                struct timer_base *base = get_timer_base(tf);
 
                /*
@@ -1371,6 +1371,13 @@ int del_timer_sync(struct timer_list *timer)
         */
        WARN_ON(in_irq() && !(timer->flags & TIMER_IRQSAFE));
 
+       /*
+        * Must be able to sleep on PREEMPT_RT because of the slowpath in
+        * del_timer_wait_running().
+        */
+       if (IS_ENABLED(CONFIG_PREEMPT_RT) && !(timer->flags & TIMER_IRQSAFE))
+               lockdep_assert_preemption_enabled();
+
        do {
                ret = try_to_del_timer_sync(timer);
 
index b89ff18..b3afd10 100644 (file)
@@ -72,17 +72,17 @@ static void trace_note(struct blk_trace *bt, pid_t pid, int action,
        struct blk_io_trace *t;
        struct ring_buffer_event *event = NULL;
        struct trace_buffer *buffer = NULL;
-       int pc = 0;
+       unsigned int trace_ctx = 0;
        int cpu = smp_processor_id();
        bool blk_tracer = blk_tracer_enabled;
        ssize_t cgid_len = cgid ? sizeof(cgid) : 0;
 
        if (blk_tracer) {
                buffer = blk_tr->array_buffer.buffer;
-               pc = preempt_count();
+               trace_ctx = tracing_gen_ctx_flags(0);
                event = trace_buffer_lock_reserve(buffer, TRACE_BLK,
                                                  sizeof(*t) + len + cgid_len,
-                                                 0, pc);
+                                                 trace_ctx);
                if (!event)
                        return;
                t = ring_buffer_event_data(event);
@@ -107,7 +107,7 @@ record_it:
                memcpy((void *) t + sizeof(*t) + cgid_len, data, len);
 
                if (blk_tracer)
-                       trace_buffer_unlock_commit(blk_tr, buffer, event, 0, pc);
+                       trace_buffer_unlock_commit(blk_tr, buffer, event, trace_ctx);
        }
 }
 
@@ -222,8 +222,9 @@ static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes,
        struct blk_io_trace *t;
        unsigned long flags = 0;
        unsigned long *sequence;
+       unsigned int trace_ctx = 0;
        pid_t pid;
-       int cpu, pc = 0;
+       int cpu;
        bool blk_tracer = blk_tracer_enabled;
        ssize_t cgid_len = cgid ? sizeof(cgid) : 0;
 
@@ -252,10 +253,10 @@ static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes,
                tracing_record_cmdline(current);
 
                buffer = blk_tr->array_buffer.buffer;
-               pc = preempt_count();
+               trace_ctx = tracing_gen_ctx_flags(0);
                event = trace_buffer_lock_reserve(buffer, TRACE_BLK,
                                                  sizeof(*t) + pdu_len + cgid_len,
-                                                 0, pc);
+                                                 trace_ctx);
                if (!event)
                        return;
                t = ring_buffer_event_data(event);
@@ -301,7 +302,7 @@ record_it:
                        memcpy((void *)t + sizeof(*t) + cgid_len, pdu_data, pdu_len);
 
                if (blk_tracer) {
-                       trace_buffer_unlock_commit(blk_tr, buffer, event, 0, pc);
+                       trace_buffer_unlock_commit(blk_tr, buffer, event, trace_ctx);
                        return;
                }
        }
index cd2d094..96107b4 100644 (file)
@@ -176,7 +176,7 @@ static union trace_eval_map_item *trace_eval_maps;
 int tracing_set_tracer(struct trace_array *tr, const char *buf);
 static void ftrace_trace_userstack(struct trace_array *tr,
                                   struct trace_buffer *buffer,
-                                  unsigned long flags, int pc);
+                                  unsigned int trace_ctx);
 
 #define MAX_TRACER_SIZE                100
 static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata;
@@ -905,23 +905,23 @@ static inline void trace_access_lock_init(void)
 
 #ifdef CONFIG_STACKTRACE
 static void __ftrace_trace_stack(struct trace_buffer *buffer,
-                                unsigned long flags,
-                                int skip, int pc, struct pt_regs *regs);
+                                unsigned int trace_ctx,
+                                int skip, struct pt_regs *regs);
 static inline void ftrace_trace_stack(struct trace_array *tr,
                                      struct trace_buffer *buffer,
-                                     unsigned long flags,
-                                     int skip, int pc, struct pt_regs *regs);
+                                     unsigned int trace_ctx,
+                                     int skip, struct pt_regs *regs);
 
 #else
 static inline void __ftrace_trace_stack(struct trace_buffer *buffer,
-                                       unsigned long flags,
-                                       int skip, int pc, struct pt_regs *regs)
+                                       unsigned int trace_ctx,
+                                       int skip, struct pt_regs *regs)
 {
 }
 static inline void ftrace_trace_stack(struct trace_array *tr,
                                      struct trace_buffer *buffer,
-                                     unsigned long flags,
-                                     int skip, int pc, struct pt_regs *regs)
+                                     unsigned long trace_ctx,
+                                     int skip, struct pt_regs *regs)
 {
 }
 
@@ -929,24 +929,24 @@ static inline void ftrace_trace_stack(struct trace_array *tr,
 
 static __always_inline void
 trace_event_setup(struct ring_buffer_event *event,
-                 int type, unsigned long flags, int pc)
+                 int type, unsigned int trace_ctx)
 {
        struct trace_entry *ent = ring_buffer_event_data(event);
 
-       tracing_generic_entry_update(ent, type, flags, pc);
+       tracing_generic_entry_update(ent, type, trace_ctx);
 }
 
 static __always_inline struct ring_buffer_event *
 __trace_buffer_lock_reserve(struct trace_buffer *buffer,
                          int type,
                          unsigned long len,
-                         unsigned long flags, int pc)
+                         unsigned int trace_ctx)
 {
        struct ring_buffer_event *event;
 
        event = ring_buffer_lock_reserve(buffer, len);
        if (event != NULL)
-               trace_event_setup(event, type, flags, pc);
+               trace_event_setup(event, type, trace_ctx);
 
        return event;
 }
@@ -1007,25 +1007,22 @@ int __trace_puts(unsigned long ip, const char *str, int size)
        struct ring_buffer_event *event;
        struct trace_buffer *buffer;
        struct print_entry *entry;
-       unsigned long irq_flags;
+       unsigned int trace_ctx;
        int alloc;
-       int pc;
 
        if (!(global_trace.trace_flags & TRACE_ITER_PRINTK))
                return 0;
 
-       pc = preempt_count();
-
        if (unlikely(tracing_selftest_running || tracing_disabled))
                return 0;
 
        alloc = sizeof(*entry) + size + 2; /* possible \n added */
 
-       local_save_flags(irq_flags);
+       trace_ctx = tracing_gen_ctx();
        buffer = global_trace.array_buffer.buffer;
        ring_buffer_nest_start(buffer);
-       event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, 
-                                           irq_flags, pc);
+       event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc,
+                                           trace_ctx);
        if (!event) {
                size = 0;
                goto out;
@@ -1044,7 +1041,7 @@ int __trace_puts(unsigned long ip, const char *str, int size)
                entry->buf[size] = '\0';
 
        __buffer_unlock_commit(buffer, event);
-       ftrace_trace_stack(&global_trace, buffer, irq_flags, 4, pc, NULL);
+       ftrace_trace_stack(&global_trace, buffer, trace_ctx, 4, NULL);
  out:
        ring_buffer_nest_end(buffer);
        return size;
@@ -1061,25 +1058,22 @@ int __trace_bputs(unsigned long ip, const char *str)
        struct ring_buffer_event *event;
        struct trace_buffer *buffer;
        struct bputs_entry *entry;
-       unsigned long irq_flags;
+       unsigned int trace_ctx;
        int size = sizeof(struct bputs_entry);
        int ret = 0;
-       int pc;
 
        if (!(global_trace.trace_flags & TRACE_ITER_PRINTK))
                return 0;
 
-       pc = preempt_count();
-
        if (unlikely(tracing_selftest_running || tracing_disabled))
                return 0;
 
-       local_save_flags(irq_flags);
+       trace_ctx = tracing_gen_ctx();
        buffer = global_trace.array_buffer.buffer;
 
        ring_buffer_nest_start(buffer);
        event = __trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size,
-                                           irq_flags, pc);
+                                           trace_ctx);
        if (!event)
                goto out;
 
@@ -1088,7 +1082,7 @@ int __trace_bputs(unsigned long ip, const char *str)
        entry->str                      = str;
 
        __buffer_unlock_commit(buffer, event);
-       ftrace_trace_stack(&global_trace, buffer, irq_flags, 4, pc, NULL);
+       ftrace_trace_stack(&global_trace, buffer, trace_ctx, 4, NULL);
 
        ret = 1;
  out:
@@ -2592,36 +2586,52 @@ enum print_line_t trace_handle_return(struct trace_seq *s)
 }
 EXPORT_SYMBOL_GPL(trace_handle_return);
 
-void
-tracing_generic_entry_update(struct trace_entry *entry, unsigned short type,
-                            unsigned long flags, int pc)
+static unsigned short migration_disable_value(void)
 {
-       struct task_struct *tsk = current;
-
-       entry->preempt_count            = pc & 0xff;
-       entry->pid                      = (tsk) ? tsk->pid : 0;
-       entry->type                     = type;
-       entry->flags =
-#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
-               (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) |
+#if defined(CONFIG_SMP) && defined(CONFIG_PREEMPT_RT)
+       return current->migration_disabled;
 #else
-               TRACE_FLAG_IRQS_NOSUPPORT |
+       return 0;
+#endif
+}
+
+unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status)
+{
+       unsigned int trace_flags = irqs_status;
+       unsigned int pc;
+
+       pc = preempt_count();
+
+       if (pc & NMI_MASK)
+               trace_flags |= TRACE_FLAG_NMI;
+       if (pc & HARDIRQ_MASK)
+               trace_flags |= TRACE_FLAG_HARDIRQ;
+       if (in_serving_softirq())
+               trace_flags |= TRACE_FLAG_SOFTIRQ;
+
+       if (tif_need_resched())
+               trace_flags |= TRACE_FLAG_NEED_RESCHED;
+       if (test_preempt_need_resched())
+               trace_flags |= TRACE_FLAG_PREEMPT_RESCHED;
+
+#ifdef CONFIG_PREEMPT_LAZY
+       if (need_resched_lazy())
+               trace_flags |= TRACE_FLAG_NEED_RESCHED_LAZY;
 #endif
-               ((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) |
-               (test_preempt_need_resched() ? TRACE_FLAG_PREEMPT_RESCHED : 0);
+
+       return (pc & 0xff) |
+               (migration_disable_value() & 0xff) << 8 |
+               (preempt_lazy_count() & 0xff) << 16 |
+               (trace_flags << 24);
 }
-EXPORT_SYMBOL_GPL(tracing_generic_entry_update);
 
 struct ring_buffer_event *
 trace_buffer_lock_reserve(struct trace_buffer *buffer,
                          int type,
                          unsigned long len,
-                         unsigned long flags, int pc)
+                         unsigned int trace_ctx)
 {
-       return __trace_buffer_lock_reserve(buffer, type, len, flags, pc);
+       return __trace_buffer_lock_reserve(buffer, type, len, trace_ctx);
 }
 
 DEFINE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
@@ -2741,7 +2751,7 @@ struct ring_buffer_event *
 trace_event_buffer_lock_reserve(struct trace_buffer **current_rb,
                          struct trace_event_file *trace_file,
                          int type, unsigned long len,
-                         unsigned long flags, int pc)
+                         unsigned int trace_ctx)
 {
        struct ring_buffer_event *entry;
        int val;
@@ -2754,7 +2764,7 @@ trace_event_buffer_lock_reserve(struct trace_buffer **current_rb,
                /* Try to use the per cpu buffer first */
                val = this_cpu_inc_return(trace_buffered_event_cnt);
                if ((len < (PAGE_SIZE - sizeof(*entry) - sizeof(entry->array[0]))) && val == 1) {
-                       trace_event_setup(entry, type, flags, pc);
+                       trace_event_setup(entry, type, trace_ctx);
                        entry->array[0] = len;
                        return entry;
                }
@@ -2762,7 +2772,7 @@ trace_event_buffer_lock_reserve(struct trace_buffer **current_rb,
        }
 
        entry = __trace_buffer_lock_reserve(*current_rb,
-                                           type, len, flags, pc);
+                                           type, len, trace_ctx);
        /*
         * If tracing is off, but we have triggers enabled
         * we still need to look at the event data. Use the temp_buffer
@@ -2771,8 +2781,8 @@ trace_event_buffer_lock_reserve(struct trace_buffer **current_rb,
         */
        if (!entry && trace_file->flags & EVENT_FILE_FL_TRIGGER_COND) {
                *current_rb = temp_buffer;
-               entry = __trace_buffer_lock_reserve(*current_rb,
-                                                   type, len, flags, pc);
+               entry = __trace_buffer_lock_reserve(*current_rb, type, len,
+                                                   trace_ctx);
        }
        return entry;
 }
@@ -2858,7 +2868,7 @@ void trace_event_buffer_commit(struct trace_event_buffer *fbuffer)
                ftrace_exports(fbuffer->event, TRACE_EXPORT_EVENT);
        event_trigger_unlock_commit_regs(fbuffer->trace_file, fbuffer->buffer,
                                    fbuffer->event, fbuffer->entry,
-                                   fbuffer->flags, fbuffer->pc, fbuffer->regs);
+                                   fbuffer->trace_ctx, fbuffer->regs);
 }
 EXPORT_SYMBOL_GPL(trace_event_buffer_commit);
 
@@ -2874,7 +2884,7 @@ EXPORT_SYMBOL_GPL(trace_event_buffer_commit);
 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
                                     struct trace_buffer *buffer,
                                     struct ring_buffer_event *event,
-                                    unsigned long flags, int pc,
+                                    unsigned int trace_ctx,
                                     struct pt_regs *regs)
 {
        __buffer_unlock_commit(buffer, event);
@@ -2885,8 +2895,8 @@ void trace_buffer_unlock_commit_regs(struct trace_array *tr,
         * and mmiotrace, but that's ok if they lose a function or
         * two. They are not that meaningful.
         */
-       ftrace_trace_stack(tr, buffer, flags, regs ? 0 : STACK_SKIP, pc, regs);
-       ftrace_trace_userstack(tr, buffer, flags, pc);
+       ftrace_trace_stack(tr, buffer, trace_ctx, regs ? 0 : STACK_SKIP, regs);
+       ftrace_trace_userstack(tr, buffer, trace_ctx);
 }
 
 /*
@@ -2900,9 +2910,8 @@ trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
 }
 
 void
-trace_function(struct trace_array *tr,
-              unsigned long ip, unsigned long parent_ip, unsigned long flags,
-              int pc)
+trace_function(struct trace_array *tr, unsigned long ip, unsigned long
+              parent_ip, unsigned int trace_ctx)
 {
        struct trace_event_call *call = &event_function;
        struct trace_buffer *buffer = tr->array_buffer.buffer;
@@ -2910,7 +2919,7 @@ trace_function(struct trace_array *tr,
        struct ftrace_entry *entry;
 
        event = __trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry),
-                                           flags, pc);
+                                           trace_ctx);
        if (!event)
                return;
        entry   = ring_buffer_event_data(event);
@@ -2944,8 +2953,8 @@ static DEFINE_PER_CPU(struct ftrace_stacks, ftrace_stacks);
 static DEFINE_PER_CPU(int, ftrace_stack_reserve);
 
 static void __ftrace_trace_stack(struct trace_buffer *buffer,
-                                unsigned long flags,
-                                int skip, int pc, struct pt_regs *regs)
+                                unsigned int trace_ctx,
+                                int skip, struct pt_regs *regs)
 {
        struct trace_event_call *call = &event_kernel_stack;
        struct ring_buffer_event *event;
@@ -2993,7 +3002,7 @@ static void __ftrace_trace_stack(struct trace_buffer *buffer,
        size = nr_entries * sizeof(unsigned long);
        event = __trace_buffer_lock_reserve(buffer, TRACE_STACK,
                                    (sizeof(*entry) - sizeof(entry->caller)) + size,
-                                   flags, pc);
+                                   trace_ctx);
        if (!event)
                goto out;
        entry = ring_buffer_event_data(event);
@@ -3014,22 +3023,22 @@ static void __ftrace_trace_stack(struct trace_buffer *buffer,
 
 static inline void ftrace_trace_stack(struct trace_array *tr,
                                      struct trace_buffer *buffer,
-                                     unsigned long flags,
-                                     int skip, int pc, struct pt_regs *regs)
+                                     unsigned int trace_ctx,
+                                     int skip, struct pt_regs *regs)
 {
        if (!(tr->trace_flags & TRACE_ITER_STACKTRACE))
                return;
 
-       __ftrace_trace_stack(buffer, flags, skip, pc, regs);
+       __ftrace_trace_stack(buffer, trace_ctx, skip, regs);
 }
 
-void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
-                  int pc)
+void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
+                  int skip)
 {
        struct trace_buffer *buffer = tr->array_buffer.buffer;
 
        if (rcu_is_watching()) {
-               __ftrace_trace_stack(buffer, flags, skip, pc, NULL);
+               __ftrace_trace_stack(buffer, trace_ctx, skip, NULL);
                return;
        }
 
@@ -3043,7 +3052,7 @@ void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
                return;
 
        rcu_irq_enter_irqson();
-       __ftrace_trace_stack(buffer, flags, skip, pc, NULL);
+       __ftrace_trace_stack(buffer, trace_ctx, skip, NULL);
        rcu_irq_exit_irqson();
 }
 
@@ -3053,19 +3062,15 @@ void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
  */
 void trace_dump_stack(int skip)
 {
-       unsigned long flags;
-
        if (tracing_disabled || tracing_selftest_running)
                return;
 
-       local_save_flags(flags);
-
 #ifndef CONFIG_UNWINDER_ORC
        /* Skip 1 to skip this function. */
        skip++;
 #endif
        __ftrace_trace_stack(global_trace.array_buffer.buffer,
-                            flags, skip, preempt_count(), NULL);
+                            tracing_gen_ctx(), skip, NULL);
 }
 EXPORT_SYMBOL_GPL(trace_dump_stack);
 
@@ -3074,7 +3079,7 @@ static DEFINE_PER_CPU(int, user_stack_count);
 
 static void
 ftrace_trace_userstack(struct trace_array *tr,
-                      struct trace_buffer *buffer, unsigned long flags, int pc)
+                      struct trace_buffer *buffer, unsigned int trace_ctx)
 {
        struct trace_event_call *call = &event_user_stack;
        struct ring_buffer_event *event;
@@ -3101,7 +3106,7 @@ ftrace_trace_userstack(struct trace_array *tr,
        __this_cpu_inc(user_stack_count);
 
        event = __trace_buffer_lock_reserve(buffer, TRACE_USER_STACK,
-                                           sizeof(*entry), flags, pc);
+                                           sizeof(*entry), trace_ctx);
        if (!event)
                goto out_drop_count;
        entry   = ring_buffer_event_data(event);
@@ -3121,7 +3126,7 @@ ftrace_trace_userstack(struct trace_array *tr,
 #else /* CONFIG_USER_STACKTRACE_SUPPORT */
 static void ftrace_trace_userstack(struct trace_array *tr,
                                   struct trace_buffer *buffer,
-                                  unsigned long flags, int pc)
+                                  unsigned int trace_ctx)
 {
 }
 #endif /* !CONFIG_USER_STACKTRACE_SUPPORT */
@@ -3251,9 +3256,9 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
        struct trace_buffer *buffer;
        struct trace_array *tr = &global_trace;
        struct bprint_entry *entry;
-       unsigned long flags;
+       unsigned int trace_ctx;
        char *tbuffer;
-       int len = 0, size, pc;
+       int len = 0, size;
 
        if (unlikely(tracing_selftest_running || tracing_disabled))
                return 0;
@@ -3261,7 +3266,7 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
        /* Don't pollute graph traces with trace_vprintk internals */
        pause_graph_tracing();
 
-       pc = preempt_count();
+       trace_ctx = tracing_gen_ctx();
        preempt_disable_notrace();
 
        tbuffer = get_trace_buf();
@@ -3275,12 +3280,11 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
        if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0)
                goto out_put;
 
-       local_save_flags(flags);
        size = sizeof(*entry) + sizeof(u32) * len;
        buffer = tr->array_buffer.buffer;
        ring_buffer_nest_start(buffer);
        event = __trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size,
-                                           flags, pc);
+                                           trace_ctx);
        if (!event)
                goto out;
        entry = ring_buffer_event_data(event);
@@ -3290,7 +3294,7 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
        memcpy(entry->buf, tbuffer, sizeof(u32) * len);
        if (!call_filter_check_discard(call, entry, buffer, event)) {
                __buffer_unlock_commit(buffer, event);
-               ftrace_trace_stack(tr, buffer, flags, 6, pc, NULL);
+               ftrace_trace_stack(tr, buffer, trace_ctx, 6, NULL);
        }
 
 out:
@@ -3313,9 +3317,9 @@ __trace_array_vprintk(struct trace_buffer *buffer,
 {
        struct trace_event_call *call = &event_print;
        struct ring_buffer_event *event;
-       int len = 0, size, pc;
+       int len = 0, size;
        struct print_entry *entry;
-       unsigned long flags;
+       unsigned int trace_ctx;
        char *tbuffer;
 
        if (tracing_disabled || tracing_selftest_running)
@@ -3324,7 +3328,7 @@ __trace_array_vprintk(struct trace_buffer *buffer,
        /* Don't pollute graph traces with trace_vprintk internals */
        pause_graph_tracing();
 
-       pc = preempt_count();
+       trace_ctx = tracing_gen_ctx();
        preempt_disable_notrace();
 
 
@@ -3336,11 +3340,10 @@ __trace_array_vprintk(struct trace_buffer *buffer,
 
        len = vscnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args);
 
-       local_save_flags(flags);
        size = sizeof(*entry) + len + 1;
        ring_buffer_nest_start(buffer);
        event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, size,
-                                           flags, pc);
+                                           trace_ctx);
        if (!event)
                goto out;
        entry = ring_buffer_event_data(event);
@@ -3349,7 +3352,7 @@ __trace_array_vprintk(struct trace_buffer *buffer,
        memcpy(&entry->buf, tbuffer, len + 1);
        if (!call_filter_check_discard(call, entry, buffer, event)) {
                __buffer_unlock_commit(buffer, event);
-               ftrace_trace_stack(&global_trace, buffer, flags, 6, pc, NULL);
+               ftrace_trace_stack(&global_trace, buffer, trace_ctx, 6, NULL);
        }
 
 out:
@@ -3815,14 +3818,17 @@ unsigned long trace_total_entries(struct trace_array *tr)
 
 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 array_buffer *buf, struct seq_file *m)
@@ -3856,13 +3862,16 @@ static void print_func_help_header_irq(struct array_buffer *buf, struct seq_file
 
        print_event_info(buf, m);
 
-       seq_printf(m, "#                            %.*s  _-----=> irqs-off\n", prec, space);
-       seq_printf(m, "#                            %.*s / _----=> need-resched\n", prec, space);
-       seq_printf(m, "#                            %.*s| / _---=> hardirq/softirq\n", prec, space);
-       seq_printf(m, "#                            %.*s|| / _--=> preempt-depth\n", prec, space);
-       seq_printf(m, "#                            %.*s||| /     delay\n", prec, space);
-       seq_printf(m, "#           TASK-PID  %.*s CPU#  ||||   TIMESTAMP  FUNCTION\n", prec, "     TGID   ");
-       seq_printf(m, "#              | |    %.*s   |   ||||      |         |\n", prec, "       |    ");
+       seq_printf(m, "#                            %.*s  _-------=> irqs-off\n", prec, space);
+       seq_printf(m, "#                            %.*s / _------=> need-resched\n", prec, space);
+       seq_printf(m, "#                            %.*s| / _-----=> need-resched-lazy\n", prec, space);
+       seq_printf(m, "#                            %.*s|| / _----=> hardirq/softirq\n", prec, space);
+       seq_printf(m, "#                            %.*s||| / _---=> preempt-depth\n", prec, space);
+       seq_printf(m, "#                            %.*s|||| / _--=> preempt-lazy-depth\n", prec, space);
+       seq_printf(m, "#                            %.*s||||| / _-=> migrate-disable\n", prec, space);
+       seq_printf(m, "#                            %.*s|||||| /     delay\n", prec, space);
+       seq_printf(m, "#           TASK-PID  %.*s CPU#  |||||||  TIMESTAMP  FUNCTION\n", prec, "     TGID   ");
+       seq_printf(m, "#              | |    %.*s   |   |||||||      |         |\n", prec, "       |    ");
 }
 
 void
@@ -6655,7 +6664,6 @@ tracing_mark_write(struct file *filp, const char __user *ubuf,
        enum event_trigger_type tt = ETT_NONE;
        struct trace_buffer *buffer;
        struct print_entry *entry;
-       unsigned long irq_flags;
        ssize_t written;
        int size;
        int len;
@@ -6675,7 +6683,6 @@ tracing_mark_write(struct file *filp, const char __user *ubuf,
 
        BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE);
 
-       local_save_flags(irq_flags);
        size = sizeof(*entry) + cnt + 2; /* add '\0' and possible '\n' */
 
        /* If less than "<faulted>", then make sure we can still add that */
@@ -6684,7 +6691,7 @@ tracing_mark_write(struct file *filp, const char __user *ubuf,
 
        buffer = tr->array_buffer.buffer;
        event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, size,
-                                           irq_flags, preempt_count());
+                                           tracing_gen_ctx());
        if (unlikely(!event))
                /* Ring buffer disabled, return as if not open for write */
                return -EBADF;
@@ -6736,7 +6743,6 @@ tracing_mark_raw_write(struct file *filp, const char __user *ubuf,
        struct ring_buffer_event *event;
        struct trace_buffer *buffer;
        struct raw_data_entry *entry;
-       unsigned long irq_flags;
        ssize_t written;
        int size;
        int len;
@@ -6758,14 +6764,13 @@ tracing_mark_raw_write(struct file *filp, const char __user *ubuf,
 
        BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE);
 
-       local_save_flags(irq_flags);
        size = sizeof(*entry) + cnt;
        if (cnt < FAULT_SIZE_ID)
                size += FAULT_SIZE_ID - cnt;
 
        buffer = tr->array_buffer.buffer;
        event = __trace_buffer_lock_reserve(buffer, TRACE_RAW_DATA, size,
-                                           irq_flags, preempt_count());
+                                           tracing_gen_ctx());
        if (!event)
                /* Ring buffer disabled, return as if not open for write */
                return -EBADF;
@@ -9318,7 +9323,6 @@ void ftrace_dump(enum ftrace_dump_mode oops_dump_mode)
        tracing_off();
 
        local_irq_save(flags);
-       printk_nmi_direct_enter();
 
        /* Simulate the iterator */
        trace_init_global_iter(&iter);
@@ -9398,7 +9402,6 @@ void ftrace_dump(enum ftrace_dump_mode oops_dump_mode)
                atomic_dec(&per_cpu_ptr(iter.array_buffer->data, cpu)->disabled);
        }
        atomic_dec(&dump_running);
-       printk_nmi_direct_exit();
        local_irq_restore(flags);
 }
 EXPORT_SYMBOL_GPL(ftrace_dump);
index 8d67f7f..bfb9fe2 100644 (file)
@@ -136,25 +136,6 @@ struct kretprobe_trace_entry_head {
        unsigned long           ret_ip;
 };
 
-/*
- * trace_flag_type is an enumeration that holds different
- * states when a trace occurs. These are:
- *  IRQS_OFF           - interrupts were disabled
- *  IRQS_NOSUPPORT     - arch does not support irqs_disabled_flags
- *  NEED_RESCHED       - reschedule is requested
- *  HARDIRQ            - inside an interrupt handler
- *  SOFTIRQ            - inside a softirq handler
- */
-enum trace_flag_type {
-       TRACE_FLAG_IRQS_OFF             = 0x01,
-       TRACE_FLAG_IRQS_NOSUPPORT       = 0x02,
-       TRACE_FLAG_NEED_RESCHED         = 0x04,
-       TRACE_FLAG_HARDIRQ              = 0x08,
-       TRACE_FLAG_SOFTIRQ              = 0x10,
-       TRACE_FLAG_PREEMPT_RESCHED      = 0x20,
-       TRACE_FLAG_NMI                  = 0x40,
-};
-
 #define TRACE_BUF_SIZE         1024
 
 struct trace_array;
@@ -745,8 +726,7 @@ struct ring_buffer_event *
 trace_buffer_lock_reserve(struct trace_buffer *buffer,
                          int type,
                          unsigned long len,
-                         unsigned long flags,
-                         int pc);
+                         unsigned int trace_ctx);
 
 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
                                                struct trace_array_cpu *data);
@@ -771,11 +751,11 @@ unsigned long trace_total_entries(struct trace_array *tr);
 void trace_function(struct trace_array *tr,
                    unsigned long ip,
                    unsigned long parent_ip,
-                   unsigned long flags, int pc);
+                   unsigned int trace_ctx);
 void trace_graph_function(struct trace_array *tr,
                    unsigned long ip,
                    unsigned long parent_ip,
-                   unsigned long flags, int pc);
+                   unsigned int trace_ctx);
 void trace_latency_header(struct seq_file *m);
 void trace_default_header(struct seq_file *m);
 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
@@ -843,11 +823,10 @@ static inline void latency_fsnotify(struct trace_array *tr) { }
 #endif
 
 #ifdef CONFIG_STACKTRACE
-void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
-                  int pc);
+void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip);
 #else
-static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
-                                int skip, int pc)
+static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
+                                int skip)
 {
 }
 #endif /* CONFIG_STACKTRACE */
@@ -987,10 +966,10 @@ extern void graph_trace_open(struct trace_iterator *iter);
 extern void graph_trace_close(struct trace_iterator *iter);
 extern int __trace_graph_entry(struct trace_array *tr,
                               struct ftrace_graph_ent *trace,
-                              unsigned long flags, int pc);
+                              unsigned int trace_ctx);
 extern void __trace_graph_return(struct trace_array *tr,
                                 struct ftrace_graph_ret *trace,
-                                unsigned long flags, int pc);
+                                unsigned int trace_ctx);
 
 #ifdef CONFIG_DYNAMIC_FTRACE
 extern struct ftrace_hash __rcu *ftrace_graph_hash;
@@ -1453,15 +1432,15 @@ extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
                                     struct trace_buffer *buffer,
                                     struct ring_buffer_event *event,
-                                    unsigned long flags, int pc,
+                                    unsigned int trcace_ctx,
                                     struct pt_regs *regs);
 
 static inline void trace_buffer_unlock_commit(struct trace_array *tr,
                                              struct trace_buffer *buffer,
                                              struct ring_buffer_event *event,
-                                             unsigned long flags, int pc)
+                                             unsigned int trace_ctx)
 {
-       trace_buffer_unlock_commit_regs(tr, buffer, event, flags, pc, NULL);
+       trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL);
 }
 
 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
@@ -1534,8 +1513,7 @@ __event_trigger_test_discard(struct trace_event_file *file,
  * @buffer: The ring buffer that the event is being written to
  * @event: The event meta data in the ring buffer
  * @entry: The event itself
- * @irq_flags: The state of the interrupts at the start of the event
- * @pc: The state of the preempt count at the start of the event.
+ * @trace_ctx: The tracing context flags.
  *
  * This is a helper function to handle triggers that require data
  * from the event itself. It also tests the event against filters and
@@ -1545,12 +1523,12 @@ static inline void
 event_trigger_unlock_commit(struct trace_event_file *file,
                            struct trace_buffer *buffer,
                            struct ring_buffer_event *event,
-                           void *entry, unsigned long irq_flags, int pc)
+                           void *entry, unsigned int trace_ctx)
 {
        enum event_trigger_type tt = ETT_NONE;
 
        if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
-               trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc);
+               trace_buffer_unlock_commit(file->tr, buffer, event, trace_ctx);
 
        if (tt)
                event_triggers_post_call(file, tt);
@@ -1562,8 +1540,7 @@ event_trigger_unlock_commit(struct trace_event_file *file,
  * @buffer: The ring buffer that the event is being written to
  * @event: The event meta data in the ring buffer
  * @entry: The event itself
- * @irq_flags: The state of the interrupts at the start of the event
- * @pc: The state of the preempt count at the start of the event.
+ * @trace_ctx: The tracing context flags.
  *
  * This is a helper function to handle triggers that require data
  * from the event itself. It also tests the event against filters and
@@ -1576,14 +1553,14 @@ static inline void
 event_trigger_unlock_commit_regs(struct trace_event_file *file,
                                 struct trace_buffer *buffer,
                                 struct ring_buffer_event *event,
-                                void *entry, unsigned long irq_flags, int pc,
+                                void *entry, unsigned int trace_ctx,
                                 struct pt_regs *regs)
 {
        enum event_trigger_type tt = ETT_NONE;
 
        if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
                trace_buffer_unlock_commit_regs(file->tr, buffer, event,
-                                               irq_flags, pc, regs);
+                                               trace_ctx, regs);
 
        if (tt)
                event_triggers_post_call(file, tt);
index eff0991..e47fdb4 100644 (file)
@@ -37,7 +37,7 @@ probe_likely_condition(struct ftrace_likely_data *f, int val, int expect)
        struct ring_buffer_event *event;
        struct trace_branch *entry;
        unsigned long flags;
-       int pc;
+       unsigned int trace_ctx;
        const char *p;
 
        if (current->trace_recursion & TRACE_BRANCH_BIT)
@@ -59,10 +59,10 @@ probe_likely_condition(struct ftrace_likely_data *f, int val, int expect)
        if (atomic_read(&data->disabled))
                goto out;
 
-       pc = preempt_count();
+       trace_ctx = tracing_gen_ctx_flags(flags);
        buffer = tr->array_buffer.buffer;
        event = trace_buffer_lock_reserve(buffer, TRACE_BRANCH,
-                                         sizeof(*entry), flags, pc);
+                                         sizeof(*entry), trace_ctx);
        if (!event)
                goto out;
 
index 643e0b1..0443dd6 100644 (file)
@@ -421,11 +421,8 @@ NOKPROBE_SYMBOL(perf_trace_buf_alloc);
 void perf_trace_buf_update(void *record, u16 type)
 {
        struct trace_entry *entry = record;
-       int pc = preempt_count();
-       unsigned long flags;
 
-       local_save_flags(flags);
-       tracing_generic_entry_update(entry, type, flags, pc);
+       tracing_generic_entry_update(entry, type, tracing_gen_ctx());
 }
 NOKPROBE_SYMBOL(perf_trace_buf_update);
 
index 7cc5f0a..1a1e9a6 100644 (file)
@@ -183,6 +183,8 @@ 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 char, migrate_disable);
+       __common_field(unsigned char, preempt_lazy_count);
 
        return ret;
 }
@@ -258,22 +260,19 @@ void *trace_event_buffer_reserve(struct trace_event_buffer *fbuffer,
            trace_event_ignore_this_pid(trace_file))
                return NULL;
 
-       local_save_flags(fbuffer->flags);
-       fbuffer->pc = preempt_count();
        /*
         * If CONFIG_PREEMPTION is enabled, then the tracepoint itself disables
         * preemption (adding one to the preempt_count). Since we are
         * interested in the preempt_count at the time the tracepoint was
         * hit, we need to subtract one to offset the increment.
         */
-       if (IS_ENABLED(CONFIG_PREEMPTION))
-               fbuffer->pc--;
+       fbuffer->trace_ctx = tracing_gen_ctx_dec();
        fbuffer->trace_file = trace_file;
 
        fbuffer->event =
                trace_event_buffer_lock_reserve(&fbuffer->buffer, trace_file,
                                                event_call->event.type, len,
-                                               fbuffer->flags, fbuffer->pc);
+                                               fbuffer->trace_ctx);
        if (!fbuffer->event)
                return NULL;
 
@@ -3689,12 +3688,11 @@ function_test_events_call(unsigned long ip, unsigned long parent_ip,
        struct trace_buffer *buffer;
        struct ring_buffer_event *event;
        struct ftrace_entry *entry;
-       unsigned long flags;
+       unsigned int trace_ctx;
        long disabled;
        int cpu;
-       int pc;
 
-       pc = preempt_count();
+       trace_ctx = tracing_gen_ctx();
        preempt_disable_notrace();
        cpu = raw_smp_processor_id();
        disabled = atomic_inc_return(&per_cpu(ftrace_test_event_disable, cpu));
@@ -3702,11 +3700,9 @@ function_test_events_call(unsigned long ip, unsigned long parent_ip,
        if (disabled != 1)
                goto out;
 
-       local_save_flags(flags);
-
        event = trace_event_buffer_lock_reserve(&buffer, &event_trace_file,
                                                TRACE_FN, sizeof(*entry),
-                                               flags, pc);
+                                               trace_ctx);
        if (!event)
                goto out;
        entry   = ring_buffer_event_data(event);
@@ -3714,7 +3710,7 @@ function_test_events_call(unsigned long ip, unsigned long parent_ip,
        entry->parent_ip                = parent_ip;
 
        event_trigger_unlock_commit(&event_trace_file, buffer, event,
-                                   entry, flags, pc);
+                                   entry, trace_ctx);
  out:
        atomic_dec(&per_cpu(ftrace_test_event_disable, cpu));
        preempt_enable_notrace();
index 22bcf7c..c188045 100644 (file)
@@ -192,7 +192,6 @@ static void *trace_alloc_entry(struct trace_event_call *call, int *size)
 static int parse_entry(char *str, struct trace_event_call *call, void **pentry)
 {
        struct ftrace_event_field *field;
-       unsigned long irq_flags;
        void *entry = NULL;
        int entry_size;
        u64 val = 0;
@@ -203,9 +202,8 @@ static int parse_entry(char *str, struct trace_event_call *call, void **pentry)
        if (!entry)
                return -ENOMEM;
 
-       local_save_flags(irq_flags);
-       tracing_generic_entry_update(entry, call->event.type, irq_flags,
-                                    preempt_count());
+       tracing_generic_entry_update(entry, call->event.type,
+                                    tracing_gen_ctx());
 
        while ((len = parse_field(str, call, &field, &val)) > 0) {
                if (is_function_field(field))
index 93e20ed..8606cb7 100644 (file)
@@ -133,15 +133,14 @@ function_trace_call(unsigned long ip, unsigned long parent_ip,
 {
        struct trace_array *tr = op->private;
        struct trace_array_cpu *data;
-       unsigned long flags;
+       unsigned int trace_ctx;
        int bit;
        int cpu;
-       int pc;
 
        if (unlikely(!tr->function_enabled))
                return;
 
-       pc = preempt_count();
+       trace_ctx = tracing_gen_ctx();
        preempt_disable_notrace();
 
        bit = trace_test_and_set_recursion(TRACE_FTRACE_START);
@@ -150,10 +149,9 @@ function_trace_call(unsigned long ip, unsigned long parent_ip,
 
        cpu = smp_processor_id();
        data = per_cpu_ptr(tr->array_buffer.data, cpu);
-       if (!atomic_read(&data->disabled)) {
-               local_save_flags(flags);
-               trace_function(tr, ip, parent_ip, flags, pc);
-       }
+       if (!atomic_read(&data->disabled))
+               trace_function(tr, ip, parent_ip, trace_ctx);
+
        trace_clear_recursion(bit);
 
  out:
@@ -187,7 +185,7 @@ function_stack_trace_call(unsigned long ip, unsigned long parent_ip,
        unsigned long flags;
        long disabled;
        int cpu;
-       int pc;
+       unsigned int trace_ctx;
 
        if (unlikely(!tr->function_enabled))
                return;
@@ -202,9 +200,9 @@ function_stack_trace_call(unsigned long ip, unsigned long parent_ip,
        disabled = atomic_inc_return(&data->disabled);
 
        if (likely(disabled == 1)) {
-               pc = preempt_count();
-               trace_function(tr, ip, parent_ip, flags, pc);
-               __trace_stack(tr, flags, STACK_SKIP, pc);
+               trace_ctx = tracing_gen_ctx_flags(flags);
+               trace_function(tr, ip, parent_ip, trace_ctx);
+               __trace_stack(tr, trace_ctx, STACK_SKIP);
        }
 
        atomic_dec(&data->disabled);
@@ -407,13 +405,11 @@ ftrace_traceoff(unsigned long ip, unsigned long parent_ip,
 
 static __always_inline void trace_stack(struct trace_array *tr)
 {
-       unsigned long flags;
-       int pc;
+       unsigned int trace_ctx;
 
-       local_save_flags(flags);
-       pc = preempt_count();
+       trace_ctx = tracing_gen_ctx();
 
-       __trace_stack(tr, flags, FTRACE_STACK_SKIP, pc);
+       __trace_stack(tr, trace_ctx, FTRACE_STACK_SKIP);
 }
 
 static void
index 60d6627..b086ba8 100644 (file)
@@ -96,8 +96,7 @@ print_graph_duration(struct trace_array *tr, unsigned long long duration,
 
 int __trace_graph_entry(struct trace_array *tr,
                                struct ftrace_graph_ent *trace,
-                               unsigned long flags,
-                               int pc)
+                               unsigned int trace_ctx)
 {
        struct trace_event_call *call = &event_funcgraph_entry;
        struct ring_buffer_event *event;
@@ -105,7 +104,7 @@ int __trace_graph_entry(struct trace_array *tr,
        struct ftrace_graph_ent_entry *entry;
 
        event = trace_buffer_lock_reserve(buffer, TRACE_GRAPH_ENT,
-                                         sizeof(*entry), flags, pc);
+                                         sizeof(*entry), trace_ctx);
        if (!event)
                return 0;
        entry   = ring_buffer_event_data(event);
@@ -129,10 +128,10 @@ int trace_graph_entry(struct ftrace_graph_ent *trace)
        struct trace_array *tr = graph_array;
        struct trace_array_cpu *data;
        unsigned long flags;
+       unsigned int trace_ctx;
        long disabled;
        int ret;
        int cpu;
-       int pc;
 
        if (trace_recursion_test(TRACE_GRAPH_NOTRACE_BIT))
                return 0;
@@ -174,8 +173,8 @@ int trace_graph_entry(struct ftrace_graph_ent *trace)
        data = per_cpu_ptr(tr->array_buffer.data, cpu);
        disabled = atomic_inc_return(&data->disabled);
        if (likely(disabled == 1)) {
-               pc = preempt_count();
-               ret = __trace_graph_entry(tr, trace, flags, pc);
+               trace_ctx = tracing_gen_ctx_flags(flags);
+               ret = __trace_graph_entry(tr, trace, trace_ctx);
        } else {
                ret = 0;
        }
@@ -188,7 +187,7 @@ int trace_graph_entry(struct ftrace_graph_ent *trace)
 
 static void
 __trace_graph_function(struct trace_array *tr,
-               unsigned long ip, unsigned long flags, int pc)
+               unsigned long ip, unsigned int trace_ctx)
 {
        u64 time = trace_clock_local();
        struct ftrace_graph_ent ent = {
@@ -202,22 +201,21 @@ __trace_graph_function(struct trace_array *tr,
                .rettime  = time,
        };
 
-       __trace_graph_entry(tr, &ent, flags, pc);
-       __trace_graph_return(tr, &ret, flags, pc);
+       __trace_graph_entry(tr, &ent, trace_ctx);
+       __trace_graph_return(tr, &ret, trace_ctx);
 }
 
 void
 trace_graph_function(struct trace_array *tr,
                unsigned long ip, unsigned long parent_ip,
-               unsigned long flags, int pc)
+               unsigned int trace_ctx)
 {
-       __trace_graph_function(tr, ip, flags, pc);
+       __trace_graph_function(tr, ip, trace_ctx);
 }
 
 void __trace_graph_return(struct trace_array *tr,
                                struct ftrace_graph_ret *trace,
-                               unsigned long flags,
-                               int pc)
+                               unsigned int trace_ctx)
 {
        struct trace_event_call *call = &event_funcgraph_exit;
        struct ring_buffer_event *event;
@@ -225,7 +223,7 @@ void __trace_graph_return(struct trace_array *tr,
        struct ftrace_graph_ret_entry *entry;
 
        event = trace_buffer_lock_reserve(buffer, TRACE_GRAPH_RET,
-                                         sizeof(*entry), flags, pc);
+                                         sizeof(*entry), trace_ctx);
        if (!event)
                return;
        entry   = ring_buffer_event_data(event);
@@ -239,9 +237,9 @@ void trace_graph_return(struct ftrace_graph_ret *trace)
        struct trace_array *tr = graph_array;
        struct trace_array_cpu *data;
        unsigned long flags;
+       unsigned int trace_ctx;
        long disabled;
        int cpu;
-       int pc;
 
        ftrace_graph_addr_finish(trace);
 
@@ -255,8 +253,8 @@ void trace_graph_return(struct ftrace_graph_ret *trace)
        data = per_cpu_ptr(tr->array_buffer.data, cpu);
        disabled = atomic_inc_return(&data->disabled);
        if (likely(disabled == 1)) {
-               pc = preempt_count();
-               __trace_graph_return(tr, trace, flags, pc);
+               trace_ctx = tracing_gen_ctx_flags(flags);
+               __trace_graph_return(tr, trace, trace_ctx);
        }
        atomic_dec(&data->disabled);
        local_irq_restore(flags);
index d071fc2..4c01c5d 100644 (file)
@@ -108,14 +108,9 @@ static void trace_hwlat_sample(struct hwlat_sample *sample)
        struct trace_buffer *buffer = tr->array_buffer.buffer;
        struct ring_buffer_event *event;
        struct hwlat_entry *entry;
-       unsigned long flags;
-       int pc;
-
-       pc = preempt_count();
-       local_save_flags(flags);
 
        event = trace_buffer_lock_reserve(buffer, TRACE_HWLAT, sizeof(*entry),
-                                         flags, pc);
+                                         tracing_gen_ctx());
        if (!event)
                return;
        entry   = ring_buffer_event_data(event);
index ee4571b..f11add8 100644 (file)
@@ -143,11 +143,14 @@ irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip,
        struct trace_array *tr = irqsoff_trace;
        struct trace_array_cpu *data;
        unsigned long flags;
+       unsigned int trace_ctx;
 
        if (!func_prolog_dec(tr, &data, &flags))
                return;
 
-       trace_function(tr, ip, parent_ip, flags, preempt_count());
+       trace_ctx = tracing_gen_ctx_flags(flags);
+
+       trace_function(tr, ip, parent_ip, trace_ctx);
 
        atomic_dec(&data->disabled);
 }
@@ -177,8 +180,8 @@ static int irqsoff_graph_entry(struct ftrace_graph_ent *trace)
        struct trace_array *tr = irqsoff_trace;
        struct trace_array_cpu *data;
        unsigned long flags;
+       unsigned int trace_ctx;
        int ret;
-       int pc;
 
        if (ftrace_graph_ignore_func(trace))
                return 0;
@@ -195,8 +198,8 @@ static int irqsoff_graph_entry(struct ftrace_graph_ent *trace)
        if (!func_prolog_dec(tr, &data, &flags))
                return 0;
 
-       pc = preempt_count();
-       ret = __trace_graph_entry(tr, trace, flags, pc);
+       trace_ctx = tracing_gen_ctx_flags(flags);
+       ret = __trace_graph_entry(tr, trace, trace_ctx);
        atomic_dec(&data->disabled);
 
        return ret;
@@ -207,15 +210,15 @@ static void irqsoff_graph_return(struct ftrace_graph_ret *trace)
        struct trace_array *tr = irqsoff_trace;
        struct trace_array_cpu *data;
        unsigned long flags;
-       int pc;
+       unsigned int trace_ctx;
 
        ftrace_graph_addr_finish(trace);
 
        if (!func_prolog_dec(tr, &data, &flags))
                return;
 
-       pc = preempt_count();
-       __trace_graph_return(tr, trace, flags, pc);
+       trace_ctx = tracing_gen_ctx_flags(flags);
+       __trace_graph_return(tr, trace, trace_ctx);
        atomic_dec(&data->disabled);
 }
 
@@ -267,12 +270,12 @@ static void irqsoff_print_header(struct seq_file *s)
 static void
 __trace_function(struct trace_array *tr,
                 unsigned long ip, unsigned long parent_ip,
-                unsigned long flags, int pc)
+                unsigned int trace_ctx)
 {
        if (is_graph(tr))
-               trace_graph_function(tr, ip, parent_ip, flags, pc);
+               trace_graph_function(tr, ip, parent_ip, trace_ctx);
        else
-               trace_function(tr, ip, parent_ip, flags, pc);
+               trace_function(tr, ip, parent_ip, trace_ctx);
 }
 
 #else
@@ -322,15 +325,13 @@ check_critical_timing(struct trace_array *tr,
 {
        u64 T0, T1, delta;
        unsigned long flags;
-       int pc;
+       unsigned int trace_ctx;
 
        T0 = data->preempt_timestamp;
        T1 = ftrace_now(cpu);
        delta = T1-T0;
 
-       local_save_flags(flags);
-
-       pc = preempt_count();
+       trace_ctx = tracing_gen_ctx();
 
        if (!report_latency(tr, delta))
                goto out;
@@ -341,9 +342,9 @@ check_critical_timing(struct trace_array *tr,
        if (!report_latency(tr, delta))
                goto out_unlock;
 
-       __trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc);
+       __trace_function(tr, CALLER_ADDR0, parent_ip, trace_ctx);
        /* Skip 5 functions to get to the irq/preempt enable function */
-       __trace_stack(tr, flags, 5, pc);
+       __trace_stack(tr, trace_ctx, 5);
 
        if (data->critical_sequence != max_sequence)
                goto out_unlock;
@@ -363,16 +364,15 @@ out_unlock:
 out:
        data->critical_sequence = max_sequence;
        data->preempt_timestamp = ftrace_now(cpu);
-       __trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc);
+       __trace_function(tr, CALLER_ADDR0, parent_ip, trace_ctx);
 }
 
 static nokprobe_inline void
-start_critical_timing(unsigned long ip, unsigned long parent_ip, int pc)
+start_critical_timing(unsigned long ip, unsigned long parent_ip)
 {
        int cpu;
        struct trace_array *tr = irqsoff_trace;
        struct trace_array_cpu *data;
-       unsigned long flags;
 
        if (!tracer_enabled || !tracing_is_enabled())
                return;
@@ -393,9 +393,7 @@ start_critical_timing(unsigned long ip, unsigned long parent_ip, int pc)
        data->preempt_timestamp = ftrace_now(cpu);
        data->critical_start = parent_ip ? : ip;
 
-       local_save_flags(flags);
-
-       __trace_function(tr, ip, parent_ip, flags, pc);
+       __trace_function(tr, ip, parent_ip, tracing_gen_ctx());
 
        per_cpu(tracing_cpu, cpu) = 1;
 
@@ -403,12 +401,12 @@ start_critical_timing(unsigned long ip, unsigned long parent_ip, int pc)
 }
 
 static nokprobe_inline void
-stop_critical_timing(unsigned long ip, unsigned long parent_ip, int pc)
+stop_critical_timing(unsigned long ip, unsigned long parent_ip)
 {
        int cpu;
        struct trace_array *tr = irqsoff_trace;
        struct trace_array_cpu *data;
-       unsigned long flags;
+       unsigned int trace_ctx;
 
        cpu = raw_smp_processor_id();
        /* Always clear the tracing cpu on stopping the trace */
@@ -428,8 +426,8 @@ stop_critical_timing(unsigned long ip, unsigned long parent_ip, int pc)
 
        atomic_inc(&data->disabled);
 
-       local_save_flags(flags);
-       __trace_function(tr, ip, parent_ip, flags, pc);
+       trace_ctx = tracing_gen_ctx();
+       __trace_function(tr, ip, parent_ip, trace_ctx);
        check_critical_timing(tr, data, parent_ip ? : ip, cpu);
        data->critical_start = 0;
        atomic_dec(&data->disabled);
@@ -438,20 +436,16 @@ stop_critical_timing(unsigned long ip, unsigned long parent_ip, int pc)
 /* start and stop critical timings used to for stoppage (in idle) */
 void start_critical_timings(void)
 {
-       int pc = preempt_count();
-
-       if (preempt_trace(pc) || irq_trace())
-               start_critical_timing(CALLER_ADDR0, CALLER_ADDR1, pc);
+       if (preempt_trace(preempt_count()) || irq_trace())
+               start_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
 }
 EXPORT_SYMBOL_GPL(start_critical_timings);
 NOKPROBE_SYMBOL(start_critical_timings);
 
 void stop_critical_timings(void)
 {
-       int pc = preempt_count();
-
-       if (preempt_trace(pc) || irq_trace())
-               stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1, pc);
+       if (preempt_trace(preempt_count()) || irq_trace())
+               stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
 }
 EXPORT_SYMBOL_GPL(stop_critical_timings);
 NOKPROBE_SYMBOL(stop_critical_timings);
@@ -613,19 +607,15 @@ static void irqsoff_tracer_stop(struct trace_array *tr)
  */
 void tracer_hardirqs_on(unsigned long a0, unsigned long a1)
 {
-       unsigned int pc = preempt_count();
-
-       if (!preempt_trace(pc) && irq_trace())
-               stop_critical_timing(a0, a1, pc);
+       if (!preempt_trace(preempt_count()) && irq_trace())
+               stop_critical_timing(a0, a1);
 }
 NOKPROBE_SYMBOL(tracer_hardirqs_on);
 
 void tracer_hardirqs_off(unsigned long a0, unsigned long a1)
 {
-       unsigned int pc = preempt_count();
-
-       if (!preempt_trace(pc) && irq_trace())
-               start_critical_timing(a0, a1, pc);
+       if (!preempt_trace(preempt_count()) && irq_trace())
+               start_critical_timing(a0, a1);
 }
 NOKPROBE_SYMBOL(tracer_hardirqs_off);
 
@@ -665,18 +655,14 @@ static struct tracer irqsoff_tracer __read_mostly =
 #ifdef CONFIG_PREEMPT_TRACER
 void tracer_preempt_on(unsigned long a0, unsigned long a1)
 {
-       int pc = preempt_count();
-
-       if (preempt_trace(pc) && !irq_trace())
-               stop_critical_timing(a0, a1, pc);
+       if (preempt_trace(preempt_count()) && !irq_trace())
+               stop_critical_timing(a0, a1);
 }
 
 void tracer_preempt_off(unsigned long a0, unsigned long a1)
 {
-       int pc = preempt_count();
-
-       if (preempt_trace(pc) && !irq_trace())
-               start_critical_timing(a0, a1, pc);
+       if (preempt_trace(preempt_count()) && !irq_trace())
+               start_critical_timing(a0, a1);
 }
 
 static int preemptoff_tracer_init(struct trace_array *tr)
index d8a9fc7..15b3af5 100644 (file)
@@ -1393,8 +1393,7 @@ __kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs,
        if (trace_trigger_soft_disabled(trace_file))
                return;
 
-       local_save_flags(fbuffer.flags);
-       fbuffer.pc = preempt_count();
+       fbuffer.trace_ctx = tracing_gen_ctx();
        fbuffer.trace_file = trace_file;
 
        dsize = __get_data_size(&tk->tp, regs);
@@ -1403,7 +1402,7 @@ __kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs,
                trace_event_buffer_lock_reserve(&fbuffer.buffer, trace_file,
                                        call->event.type,
                                        sizeof(*entry) + tk->tp.size + dsize,
-                                       fbuffer.flags, fbuffer.pc);
+                                       fbuffer.trace_ctx);
        if (!fbuffer.event)
                return;
 
@@ -1441,8 +1440,7 @@ __kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,
        if (trace_trigger_soft_disabled(trace_file))
                return;
 
-       local_save_flags(fbuffer.flags);
-       fbuffer.pc = preempt_count();
+       fbuffer.trace_ctx = tracing_gen_ctx();
        fbuffer.trace_file = trace_file;
 
        dsize = __get_data_size(&tk->tp, regs);
@@ -1450,7 +1448,7 @@ __kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,
                trace_event_buffer_lock_reserve(&fbuffer.buffer, trace_file,
                                        call->event.type,
                                        sizeof(*entry) + tk->tp.size + dsize,
-                                       fbuffer.flags, fbuffer.pc);
+                                       fbuffer.trace_ctx);
        if (!fbuffer.event)
                return;
 
index 84582bf..7221ae0 100644 (file)
@@ -300,10 +300,11 @@ static void __trace_mmiotrace_rw(struct trace_array *tr,
        struct trace_buffer *buffer = tr->array_buffer.buffer;
        struct ring_buffer_event *event;
        struct trace_mmiotrace_rw *entry;
-       int pc = preempt_count();
+       unsigned int trace_ctx;
 
+       trace_ctx = tracing_gen_ctx_flags(0);
        event = trace_buffer_lock_reserve(buffer, TRACE_MMIO_RW,
-                                         sizeof(*entry), 0, pc);
+                                         sizeof(*entry), trace_ctx);
        if (!event) {
                atomic_inc(&dropped_count);
                return;
@@ -312,7 +313,7 @@ static void __trace_mmiotrace_rw(struct trace_array *tr,
        entry->rw                       = *rw;
 
        if (!call_filter_check_discard(call, entry, buffer, event))
-               trace_buffer_unlock_commit(tr, buffer, event, 0, pc);
+               trace_buffer_unlock_commit(tr, buffer, event, trace_ctx);
 }
 
 void mmio_trace_rw(struct mmiotrace_rw *rw)
@@ -330,10 +331,11 @@ static void __trace_mmiotrace_map(struct trace_array *tr,
        struct trace_buffer *buffer = tr->array_buffer.buffer;
        struct ring_buffer_event *event;
        struct trace_mmiotrace_map *entry;
-       int pc = preempt_count();
+       unsigned int trace_ctx;
 
+       trace_ctx = tracing_gen_ctx_flags(0);
        event = trace_buffer_lock_reserve(buffer, TRACE_MMIO_MAP,
-                                         sizeof(*entry), 0, pc);
+                                         sizeof(*entry), trace_ctx);
        if (!event) {
                atomic_inc(&dropped_count);
                return;
@@ -342,7 +344,7 @@ static void __trace_mmiotrace_map(struct trace_array *tr,
        entry->map                      = *map;
 
        if (!call_filter_check_discard(call, entry, buffer, event))
-               trace_buffer_unlock_commit(tr, buffer, event, 0, pc);
+               trace_buffer_unlock_commit(tr, buffer, event, trace_ctx);
 }
 
 void mmio_trace_mapping(struct mmiotrace_map *map)
index 000e9dc..bc24ae8 100644 (file)
@@ -441,6 +441,7 @@ 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;
@@ -471,6 +472,9 @@ 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' :
@@ -479,14 +483,25 @@ 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 97b10bb..f1c6033 100644 (file)
@@ -67,7 +67,7 @@ static bool function_enabled;
 static int
 func_prolog_preempt_disable(struct trace_array *tr,
                            struct trace_array_cpu **data,
-                           int *pc)
+                           unsigned int *trace_ctx)
 {
        long disabled;
        int cpu;
@@ -75,7 +75,7 @@ func_prolog_preempt_disable(struct trace_array *tr,
        if (likely(!wakeup_task))
                return 0;
 
-       *pc = preempt_count();
+       *trace_ctx = tracing_gen_ctx();
        preempt_disable_notrace();
 
        cpu = raw_smp_processor_id();
@@ -116,8 +116,8 @@ static int wakeup_graph_entry(struct ftrace_graph_ent *trace)
 {
        struct trace_array *tr = wakeup_trace;
        struct trace_array_cpu *data;
-       unsigned long flags;
-       int pc, ret = 0;
+       unsigned int trace_ctx;
+       int ret = 0;
 
        if (ftrace_graph_ignore_func(trace))
                return 0;
@@ -131,11 +131,10 @@ static int wakeup_graph_entry(struct ftrace_graph_ent *trace)
        if (ftrace_graph_notrace_addr(trace->func))
                return 1;
 
-       if (!func_prolog_preempt_disable(tr, &data, &pc))
+       if (!func_prolog_preempt_disable(tr, &data, &trace_ctx))
                return 0;
 
-       local_save_flags(flags);
-       ret = __trace_graph_entry(tr, trace, flags, pc);
+       ret = __trace_graph_entry(tr, trace, trace_ctx);
        atomic_dec(&data->disabled);
        preempt_enable_notrace();
 
@@ -146,16 +145,14 @@ static void wakeup_graph_return(struct ftrace_graph_ret *trace)
 {
        struct trace_array *tr = wakeup_trace;
        struct trace_array_cpu *data;
-       unsigned long flags;
-       int pc;
+       unsigned int trace_ctx;
 
        ftrace_graph_addr_finish(trace);
 
-       if (!func_prolog_preempt_disable(tr, &data, &pc))
+       if (!func_prolog_preempt_disable(tr, &data, &trace_ctx))
                return;
 
-       local_save_flags(flags);
-       __trace_graph_return(tr, trace, flags, pc);
+       __trace_graph_return(tr, trace, trace_ctx);
        atomic_dec(&data->disabled);
 
        preempt_enable_notrace();
@@ -217,13 +214,13 @@ wakeup_tracer_call(unsigned long ip, unsigned long parent_ip,
        struct trace_array *tr = wakeup_trace;
        struct trace_array_cpu *data;
        unsigned long flags;
-       int pc;
+       unsigned int trace_ctx;
 
-       if (!func_prolog_preempt_disable(tr, &data, &pc))
+       if (!func_prolog_preempt_disable(tr, &data, &trace_ctx))
                return;
 
        local_irq_save(flags);
-       trace_function(tr, ip, parent_ip, flags, pc);
+       trace_function(tr, ip, parent_ip, trace_ctx);
        local_irq_restore(flags);
 
        atomic_dec(&data->disabled);
@@ -303,12 +300,12 @@ static void wakeup_print_header(struct seq_file *s)
 static void
 __trace_function(struct trace_array *tr,
                 unsigned long ip, unsigned long parent_ip,
-                unsigned long flags, int pc)
+                unsigned int trace_ctx)
 {
        if (is_graph(tr))
-               trace_graph_function(tr, ip, parent_ip, flags, pc);
+               trace_graph_function(tr, ip, parent_ip, trace_ctx);
        else
-               trace_function(tr, ip, parent_ip, flags, pc);
+               trace_function(tr, ip, parent_ip, trace_ctx);
 }
 
 static int wakeup_flag_changed(struct trace_array *tr, u32 mask, int set)
@@ -375,7 +372,7 @@ static void
 tracing_sched_switch_trace(struct trace_array *tr,
                           struct task_struct *prev,
                           struct task_struct *next,
-                          unsigned long flags, int pc)
+                          unsigned int trace_ctx)
 {
        struct trace_event_call *call = &event_context_switch;
        struct trace_buffer *buffer = tr->array_buffer.buffer;
@@ -383,7 +380,7 @@ tracing_sched_switch_trace(struct trace_array *tr,
        struct ctx_switch_entry *entry;
 
        event = trace_buffer_lock_reserve(buffer, TRACE_CTX,
-                                         sizeof(*entry), flags, pc);
+                                         sizeof(*entry), trace_ctx);
        if (!event)
                return;
        entry   = ring_buffer_event_data(event);
@@ -396,14 +393,14 @@ tracing_sched_switch_trace(struct trace_array *tr,
        entry->next_cpu = task_cpu(next);
 
        if (!call_filter_check_discard(call, entry, buffer, event))
-               trace_buffer_unlock_commit(tr, buffer, event, flags, pc);
+               trace_buffer_unlock_commit(tr, buffer, event, trace_ctx);
 }
 
 static void
 tracing_sched_wakeup_trace(struct trace_array *tr,
                           struct task_struct *wakee,
                           struct task_struct *curr,
-                          unsigned long flags, int pc)
+                          unsigned int trace_ctx)
 {
        struct trace_event_call *call = &event_wakeup;
        struct ring_buffer_event *event;
@@ -411,7 +408,7 @@ tracing_sched_wakeup_trace(struct trace_array *tr,
        struct trace_buffer *buffer = tr->array_buffer.buffer;
 
        event = trace_buffer_lock_reserve(buffer, TRACE_WAKE,
-                                         sizeof(*entry), flags, pc);
+                                         sizeof(*entry), trace_ctx);
        if (!event)
                return;
        entry   = ring_buffer_event_data(event);
@@ -424,7 +421,7 @@ tracing_sched_wakeup_trace(struct trace_array *tr,
        entry->next_cpu                 = task_cpu(wakee);
 
        if (!call_filter_check_discard(call, entry, buffer, event))
-               trace_buffer_unlock_commit(tr, buffer, event, flags, pc);
+               trace_buffer_unlock_commit(tr, buffer, event, trace_ctx);
 }
 
 static void notrace
@@ -436,7 +433,7 @@ probe_wakeup_sched_switch(void *ignore, bool preempt,
        unsigned long flags;
        long disabled;
        int cpu;
-       int pc;
+       unsigned int trace_ctx;
 
        tracing_record_cmdline(prev);
 
@@ -455,8 +452,6 @@ probe_wakeup_sched_switch(void *ignore, bool preempt,
        if (next != wakeup_task)
                return;
 
-       pc = preempt_count();
-
        /* disable local data, not wakeup_cpu data */
        cpu = raw_smp_processor_id();
        disabled = atomic_inc_return(&per_cpu_ptr(wakeup_trace->array_buffer.data, cpu)->disabled);
@@ -464,6 +459,8 @@ probe_wakeup_sched_switch(void *ignore, bool preempt,
                goto out;
 
        local_irq_save(flags);
+       trace_ctx = tracing_gen_ctx_flags(flags);
+
        arch_spin_lock(&wakeup_lock);
 
        /* We could race with grabbing wakeup_lock */
@@ -473,9 +470,9 @@ probe_wakeup_sched_switch(void *ignore, bool preempt,
        /* The task we are waiting for is waking up */
        data = per_cpu_ptr(wakeup_trace->array_buffer.data, wakeup_cpu);
 
-       __trace_function(wakeup_trace, CALLER_ADDR0, CALLER_ADDR1, flags, pc);
-       tracing_sched_switch_trace(wakeup_trace, prev, next, flags, pc);
-       __trace_stack(wakeup_trace, flags, 0, pc);
+       __trace_function(wakeup_trace, CALLER_ADDR0, CALLER_ADDR1, trace_ctx);
+       tracing_sched_switch_trace(wakeup_trace, prev, next, trace_ctx);
+       __trace_stack(wakeup_trace, trace_ctx, 0);
 
        T0 = data->preempt_timestamp;
        T1 = ftrace_now(cpu);
@@ -527,9 +524,8 @@ probe_wakeup(void *ignore, struct task_struct *p)
 {
        struct trace_array_cpu *data;
        int cpu = smp_processor_id();
-       unsigned long flags;
        long disabled;
-       int pc;
+       unsigned int trace_ctx;
 
        if (likely(!tracer_enabled))
                return;
@@ -550,11 +546,12 @@ probe_wakeup(void *ignore, struct task_struct *p)
            (!dl_task(p) && (p->prio >= wakeup_prio || p->prio >= current->prio)))
                return;
 
-       pc = preempt_count();
        disabled = atomic_inc_return(&per_cpu_ptr(wakeup_trace->array_buffer.data, cpu)->disabled);
        if (unlikely(disabled != 1))
                goto out;
 
+       trace_ctx = tracing_gen_ctx();
+
        /* interrupts should be off from try_to_wake_up */
        arch_spin_lock(&wakeup_lock);
 
@@ -581,19 +578,17 @@ probe_wakeup(void *ignore, struct task_struct *p)
 
        wakeup_task = get_task_struct(p);
 
-       local_save_flags(flags);
-
        data = per_cpu_ptr(wakeup_trace->array_buffer.data, wakeup_cpu);
        data->preempt_timestamp = ftrace_now(cpu);
-       tracing_sched_wakeup_trace(wakeup_trace, p, current, flags, pc);
-       __trace_stack(wakeup_trace, flags, 0, pc);
+       tracing_sched_wakeup_trace(wakeup_trace, p, current, trace_ctx);
+       __trace_stack(wakeup_trace, trace_ctx, 0);
 
        /*
         * We must be careful in using CALLER_ADDR2. But since wake_up
         * is not called by an assembly function  (where as schedule is)
         * it should be safe to use it here.
         */
-       __trace_function(wakeup_trace, CALLER_ADDR1, CALLER_ADDR2, flags, pc);
+       __trace_function(wakeup_trace, CALLER_ADDR1, CALLER_ADDR2, trace_ctx);
 
 out_locked:
        arch_spin_unlock(&wakeup_lock);
index d85a2f0..8bfcd3b 100644 (file)
@@ -298,9 +298,8 @@ static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id)
        struct syscall_metadata *sys_data;
        struct ring_buffer_event *event;
        struct trace_buffer *buffer;
-       unsigned long irq_flags;
+       unsigned int trace_ctx;
        unsigned long args[6];
-       int pc;
        int syscall_nr;
        int size;
 
@@ -322,12 +321,11 @@ static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id)
 
        size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args;
 
-       local_save_flags(irq_flags);
-       pc = preempt_count();
+       trace_ctx = tracing_gen_ctx();
 
        buffer = tr->array_buffer.buffer;
        event = trace_buffer_lock_reserve(buffer,
-                       sys_data->enter_event->event.type, size, irq_flags, pc);
+                       sys_data->enter_event->event.type, size, trace_ctx);
        if (!event)
                return;
 
@@ -337,7 +335,7 @@ static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id)
        memcpy(entry->args, args, sizeof(unsigned long) * sys_data->nb_args);
 
        event_trigger_unlock_commit(trace_file, buffer, event, entry,
-                                   irq_flags, pc);
+                                   trace_ctx);
 }
 
 static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret)
@@ -348,8 +346,7 @@ static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret)
        struct syscall_metadata *sys_data;
        struct ring_buffer_event *event;
        struct trace_buffer *buffer;
-       unsigned long irq_flags;
-       int pc;
+       unsigned int trace_ctx;
        int syscall_nr;
 
        syscall_nr = trace_get_syscall_nr(current, regs);
@@ -368,13 +365,12 @@ static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret)
        if (!sys_data)
                return;
 
-       local_save_flags(irq_flags);
-       pc = preempt_count();
+       trace_ctx = tracing_gen_ctx();
 
        buffer = tr->array_buffer.buffer;
        event = trace_buffer_lock_reserve(buffer,
                        sys_data->exit_event->event.type, sizeof(*entry),
-                       irq_flags, pc);
+                       trace_ctx);
        if (!event)
                return;
 
@@ -383,7 +379,7 @@ static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret)
        entry->ret = syscall_get_return_value(current, regs);
 
        event_trigger_unlock_commit(trace_file, buffer, event, entry,
-                                   irq_flags, pc);
+                                   trace_ctx);
 }
 
 static int reg_event_syscall_enter(struct trace_event_file *file,
index 9900d4e..7be4f5d 100644 (file)
@@ -965,7 +965,7 @@ static void __uprobe_trace_func(struct trace_uprobe *tu,
        esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
        size = esize + tu->tp.size + dsize;
        event = trace_event_buffer_lock_reserve(&buffer, trace_file,
-                                               call->event.type, size, 0, 0);
+                                               call->event.type, size, 0);
        if (!event)
                return;
 
@@ -981,7 +981,7 @@ static void __uprobe_trace_func(struct trace_uprobe *tu,
 
        memcpy(data, ucb->buf, tu->tp.size + dsize);
 
-       event_trigger_unlock_commit(trace_file, buffer, event, entry, 0, 0);
+       event_trigger_unlock_commit(trace_file, buffer, event, entry, 0);
 }
 
 /* uprobe handler */
index fdf5fa4..dbeafe2 100644 (file)
@@ -4928,6 +4928,10 @@ static void unbind_workers(int cpu)
                pool->flags |= POOL_DISASSOCIATED;
 
                raw_spin_unlock_irq(&pool->lock);
+
+               for_each_pool_worker(worker, pool)
+                       WARN_ON_ONCE(set_cpus_allowed_ptr(worker->task, cpu_active_mask) < 0);
+
                mutex_unlock(&wq_pool_attach_mutex);
 
                /*
index 95f9095..a601578 100644 (file)
@@ -1328,7 +1328,7 @@ config DEBUG_ATOMIC_SLEEP
 
 config DEBUG_LOCKING_API_SELFTESTS
        bool "Locking API boot-time self-tests"
-       depends on DEBUG_KERNEL
+       depends on DEBUG_KERNEL && !PREEMPT_RT
        help
          Say Y here if you want the kernel to run a short self-test during
          bootup. The self-test checks whether common types of locking bugs
index 4ab398a..9c681f2 100644 (file)
--- a/lib/bug.c
+++ b/lib/bug.c
@@ -202,6 +202,7 @@ enum bug_trap_type report_bug(unsigned long bugaddr, struct pt_regs *regs)
        else
                pr_crit("Kernel BUG at %pB [verbose debug info unavailable]\n",
                        (void *)bugaddr);
+       pr_flush(1000, true);
 
        return BUG_TRAP_TYPE_BUG;
 }
index fb22fb2..c3c76b8 100644 (file)
@@ -261,3 +261,21 @@ int cpumask_any_and_distribute(const struct cpumask *src1p,
        return next;
 }
 EXPORT_SYMBOL(cpumask_any_and_distribute);
+
+int cpumask_any_distribute(const struct cpumask *srcp)
+{
+       int next, prev;
+
+       /* NOTE: our first selection will skip 0. */
+       prev = __this_cpu_read(distribute_cpu_mask_prev);
+
+       next = cpumask_next(prev, srcp);
+       if (next >= nr_cpu_ids)
+               next = cpumask_first(srcp);
+
+       if (next < nr_cpu_ids)
+               __this_cpu_write(distribute_cpu_mask_prev, next);
+
+       return next;
+}
+EXPORT_SYMBOL(cpumask_any_distribute);
index 9e14ae0..083882a 100644 (file)
@@ -557,7 +557,10 @@ __debug_object_init(void *addr, const struct debug_obj_descr *descr, int onstack
        struct debug_obj *obj;
        unsigned long flags;
 
-       fill_pool();
+#ifdef CONFIG_PREEMPT_RT
+       if (preempt_count() == 0 && !irqs_disabled())
+#endif
+               fill_pool();
 
        db = get_bucket((unsigned long) addr);
 
index a00ee6e..f5a33b6 100644 (file)
@@ -12,6 +12,7 @@
 #include <linux/atomic.h>
 #include <linux/kexec.h>
 #include <linux/utsname.h>
+#include <linux/stop_machine.h>
 
 static char dump_stack_arch_desc_str[128];
 
@@ -57,6 +58,7 @@ void dump_stack_print_info(const char *log_lvl)
                       log_lvl, dump_stack_arch_desc_str);
 
        print_worker_info(log_lvl, current);
+       print_stop_info(log_lvl, current);
 }
 
 /**
index 2f17b48..7557bf7 100644 (file)
@@ -37,6 +37,7 @@ 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);
 
@@ -72,6 +73,7 @@ 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);
 
@@ -96,6 +98,7 @@ 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
@@ -133,6 +136,7 @@ static void __latent_entropy irq_poll_softirq(struct softirq_action *h)
                __raise_softirq_irqoff(IRQ_POLL_SOFTIRQ);
 
        local_irq_enable();
+       preempt_check_resched_rt();
 }
 
 /**
@@ -196,6 +200,7 @@ 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 76c52b0..98c376b 100644 (file)
@@ -787,6 +787,8 @@ GENERATE_TESTCASE(init_held_rtmutex);
 #include "locking-selftest-spin-hardirq.h"
 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_spin)
 
+#ifndef CONFIG_PREEMPT_RT
+
 #include "locking-selftest-rlock-hardirq.h"
 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_rlock)
 
@@ -802,9 +804,12 @@ 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
 /*
  * Enabling hardirqs with a softirq-safe lock held:
  */
@@ -837,6 +842,8 @@ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_rlock)
 #undef E1
 #undef E2
 
+#endif
+
 /*
  * Enabling irqs with an irq-safe lock held:
  */
@@ -860,6 +867,8 @@ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_rlock)
 #include "locking-selftest-spin-hardirq.h"
 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_spin)
 
+#ifndef CONFIG_PREEMPT_RT
+
 #include "locking-selftest-rlock-hardirq.h"
 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_rlock)
 
@@ -875,6 +884,8 @@ 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
 
@@ -906,6 +917,8 @@ GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_wlock)
 #include "locking-selftest-spin-hardirq.h"
 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_spin)
 
+#ifndef CONFIG_PREEMPT_RT
+
 #include "locking-selftest-rlock-hardirq.h"
 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_rlock)
 
@@ -921,6 +934,8 @@ 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
@@ -954,6 +969,8 @@ GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_wlock)
 #include "locking-selftest-spin-hardirq.h"
 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_spin)
 
+#ifndef CONFIG_PREEMPT_RT
+
 #include "locking-selftest-rlock-hardirq.h"
 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_rlock)
 
@@ -969,10 +986,14 @@ 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
+
 /*
  * read-lock / write-lock irq inversion.
  *
@@ -1162,6 +1183,11 @@ GENERATE_PERMUTATIONS_3_EVENTS(W1W2_R2R3_R3W1)
 #undef E1
 #undef E2
 #undef E3
+
+#endif
+
+#ifndef CONFIG_PREEMPT_RT
+
 /*
  * read-lock / write-lock recursion that is actually safe.
  */
@@ -1208,6 +1234,8 @@ GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_soft_wlock)
 #undef E2
 #undef E3
 
+#endif
+
 /*
  * read-lock / write-lock recursion that is unsafe.
  */
@@ -2456,6 +2484,7 @@ void locking_selftest(void)
 
        printk("  --------------------------------------------------------------------------\n");
 
+#ifndef CONFIG_PREEMPT_RT
        /*
         * irq-context testcases:
         */
@@ -2470,6 +2499,28 @@ void locking_selftest(void)
        DO_TESTCASE_6x2x2RW("irq read-recursion #2", irq_read_recursion2);
        DO_TESTCASE_6x2x2RW("irq read-recursion #3", irq_read_recursion3);
 
+#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();
 
        force_read_lock_recursive = 0;
index 8abe187..b09a490 100644 (file)
@@ -75,12 +75,6 @@ void nmi_trigger_cpumask_backtrace(const cpumask_t *mask,
                touch_softlockup_watchdog();
        }
 
-       /*
-        * Force flush any remote buffers that might be stuck in IRQ context
-        * and therefore could not run their irq_work.
-        */
-       printk_safe_flush();
-
        clear_bit_unlock(0, &backtrace_flag);
        put_cpu();
 }
index a597789..907f590 100644 (file)
@@ -892,7 +892,7 @@ 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);
index 525222e..1c1dbd3 100644 (file)
@@ -26,6 +26,11 @@ unsigned int check_preemption_disabled(const char *what1, const char *what2)
        if (current->nr_cpus_allowed == 1)
                goto out;
 
+#ifdef CONFIG_SMP
+       if (current->migration_disabled)
+               goto out;
+#endif
+
        /*
         * It is valid to assume CPU-locality during early bootup:
         */
index f1a020b..864554e 100644 (file)
@@ -480,6 +480,21 @@ static int __init test_lockup_init(void)
                return -EINVAL;
 
 #ifdef CONFIG_DEBUG_SPINLOCK
+#ifdef CONFIG_PREEMPT_RT
+       if (test_magic(lock_spinlock_ptr,
+                      offsetof(spinlock_t, lock.wait_lock.magic),
+                      SPINLOCK_MAGIC) ||
+           test_magic(lock_rwlock_ptr,
+                      offsetof(rwlock_t, rtmutex.wait_lock.magic),
+                      SPINLOCK_MAGIC) ||
+           test_magic(lock_mutex_ptr,
+                      offsetof(struct mutex, lock.wait_lock.magic),
+                      SPINLOCK_MAGIC) ||
+           test_magic(lock_rwsem_ptr,
+                      offsetof(struct rw_semaphore, rtmutex.wait_lock.magic),
+                      SPINLOCK_MAGIC))
+               return -EINVAL;
+#else
        if (test_magic(lock_spinlock_ptr,
                       offsetof(spinlock_t, rlock.magic),
                       SPINLOCK_MAGIC) ||
@@ -494,6 +509,7 @@ static int __init test_lockup_init(void)
                       SPINLOCK_MAGIC))
                return -EINVAL;
 #endif
+#endif
 
        if ((wait_state != TASK_RUNNING ||
             (call_cond_resched && !reacquire_locks) ||
diff --git a/localversion-rt b/localversion-rt
new file mode 100644 (file)
index 0000000..40d81d8
--- /dev/null
@@ -0,0 +1 @@
+-rt62
index 3965f52..4480726 100644 (file)
@@ -412,7 +412,7 @@ 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
        select COMPACTION
        select XARRAY_MULTI
        help
@@ -908,4 +908,7 @@ config ARCH_HAS_HUGEPD
 config MAPPING_DIRTY_HELPERS
         bool
 
+config KMAP_LOCAL
+       bool
+
 endmenu
index 1352a27..72b9a2d 100644 (file)
 #include <asm/tlbflush.h>
 #include <linux/vmalloc.h>
 
-#if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32)
-DEFINE_PER_CPU(int, __kmap_atomic_idx);
-#endif
-
 /*
  * Virtual_count is not a pure "count".
  *  0 means that it is not mapped, and has not been mapped
@@ -108,9 +104,7 @@ static inline wait_queue_head_t *get_pkmap_wait_queue_head(unsigned int color)
 atomic_long_t _totalhigh_pages __read_mostly;
 EXPORT_SYMBOL(_totalhigh_pages);
 
-EXPORT_PER_CPU_SYMBOL(__kmap_atomic_idx);
-
-unsigned int nr_free_highpages (void)
+unsigned int __nr_free_highpages (void)
 {
        struct zone *zone;
        unsigned int pages = 0;
@@ -147,7 +141,7 @@ pte_t * pkmap_page_table;
                do { spin_unlock(&kmap_lock); (void)(flags); } while (0)
 #endif
 
-struct page *kmap_to_page(void *vaddr)
+struct page *__kmap_to_page(void *vaddr)
 {
        unsigned long addr = (unsigned long)vaddr;
 
@@ -158,7 +152,7 @@ struct page *kmap_to_page(void *vaddr)
 
        return virt_to_page(addr);
 }
-EXPORT_SYMBOL(kmap_to_page);
+EXPORT_SYMBOL(__kmap_to_page);
 
 static void flush_all_zero_pkmaps(void)
 {
@@ -200,10 +194,7 @@ static void flush_all_zero_pkmaps(void)
                flush_tlb_kernel_range(PKMAP_ADDR(0), PKMAP_ADDR(LAST_PKMAP));
 }
 
-/**
- * kmap_flush_unused - flush all unused kmap mappings in order to remove stray mappings
- */
-void kmap_flush_unused(void)
+void __kmap_flush_unused(void)
 {
        lock_kmap();
        flush_all_zero_pkmaps();
@@ -367,9 +358,250 @@ void kunmap_high(struct page *page)
        if (need_wakeup)
                wake_up(pkmap_map_wait);
 }
-
 EXPORT_SYMBOL(kunmap_high);
-#endif /* CONFIG_HIGHMEM */
+#endif /* CONFIG_HIGHMEM */
+
+#ifdef CONFIG_KMAP_LOCAL
+
+#include <asm/kmap_size.h>
+
+/*
+ * With DEBUG_HIGHMEM the stack depth is doubled and every second
+ * slot is unused which acts as a guard page
+ */
+#ifdef CONFIG_DEBUG_HIGHMEM
+# define KM_INCR       2
+#else
+# define KM_INCR       1
+#endif
+
+static inline int kmap_local_idx_push(void)
+{
+       WARN_ON_ONCE(in_irq() && !irqs_disabled());
+       current->kmap_ctrl.idx += KM_INCR;
+       BUG_ON(current->kmap_ctrl.idx >= KM_MAX_IDX);
+       return current->kmap_ctrl.idx - 1;
+}
+
+static inline int kmap_local_idx(void)
+{
+       return current->kmap_ctrl.idx - 1;
+}
+
+static inline void kmap_local_idx_pop(void)
+{
+       current->kmap_ctrl.idx -= KM_INCR;
+       BUG_ON(current->kmap_ctrl.idx < 0);
+}
+
+#ifndef arch_kmap_local_post_map
+# define arch_kmap_local_post_map(vaddr, pteval)       do { } while (0)
+#endif
+
+#ifndef arch_kmap_local_pre_unmap
+# define arch_kmap_local_pre_unmap(vaddr)              do { } while (0)
+#endif
+
+#ifndef arch_kmap_local_post_unmap
+# define arch_kmap_local_post_unmap(vaddr)             do { } while (0)
+#endif
+
+#ifndef arch_kmap_local_map_idx
+#define arch_kmap_local_map_idx(idx, pfn)      kmap_local_calc_idx(idx)
+#endif
+
+#ifndef arch_kmap_local_unmap_idx
+#define arch_kmap_local_unmap_idx(idx, vaddr)  kmap_local_calc_idx(idx)
+#endif
+
+#ifndef arch_kmap_local_high_get
+static inline void *arch_kmap_local_high_get(struct page *page)
+{
+       return NULL;
+}
+#endif
+
+/* Unmap a local mapping which was obtained by kmap_high_get() */
+static inline bool kmap_high_unmap_local(unsigned long vaddr)
+{
+#ifdef ARCH_NEEDS_KMAP_HIGH_GET
+       if (vaddr >= PKMAP_ADDR(0) && vaddr < PKMAP_ADDR(LAST_PKMAP)) {
+               kunmap_high(pte_page(pkmap_page_table[PKMAP_NR(vaddr)]));
+               return true;
+       }
+#endif
+       return false;
+}
+
+static inline int kmap_local_calc_idx(int idx)
+{
+       return idx + KM_MAX_IDX * smp_processor_id();
+}
+
+static pte_t *__kmap_pte;
+
+static pte_t *kmap_get_pte(void)
+{
+       if (!__kmap_pte)
+               __kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
+       return __kmap_pte;
+}
+
+void *__kmap_local_pfn_prot(unsigned long pfn, pgprot_t prot)
+{
+       pte_t pteval, *kmap_pte = kmap_get_pte();
+       unsigned long vaddr;
+       int idx;
+
+       /*
+        * Disable migration so resulting virtual address is stable
+        * accross preemption.
+        */
+       migrate_disable();
+       preempt_disable();
+       idx = arch_kmap_local_map_idx(kmap_local_idx_push(), pfn);
+       vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+       BUG_ON(!pte_none(*(kmap_pte - idx)));
+       pteval = pfn_pte(pfn, prot);
+       set_pte_at(&init_mm, vaddr, kmap_pte - idx, pteval);
+       arch_kmap_local_post_map(vaddr, pteval);
+       current->kmap_ctrl.pteval[kmap_local_idx()] = pteval;
+       preempt_enable();
+
+       return (void *)vaddr;
+}
+EXPORT_SYMBOL_GPL(__kmap_local_pfn_prot);
+
+void *__kmap_local_page_prot(struct page *page, pgprot_t prot)
+{
+       void *kmap;
+
+       if (!PageHighMem(page))
+               return page_address(page);
+
+       /* Try kmap_high_get() if architecture has it enabled */
+       kmap = arch_kmap_local_high_get(page);
+       if (kmap)
+               return kmap;
+
+       return __kmap_local_pfn_prot(page_to_pfn(page), prot);
+}
+EXPORT_SYMBOL(__kmap_local_page_prot);
+
+void kunmap_local_indexed(void *vaddr)
+{
+       unsigned long addr = (unsigned long) vaddr & PAGE_MASK;
+       pte_t *kmap_pte = kmap_get_pte();
+       int idx;
+
+       if (addr < __fix_to_virt(FIX_KMAP_END) ||
+           addr > __fix_to_virt(FIX_KMAP_BEGIN)) {
+               /*
+                * Handle mappings which were obtained by kmap_high_get()
+                * first as the virtual address of such mappings is below
+                * PAGE_OFFSET. Warn for all other addresses which are in
+                * the user space part of the virtual address space.
+                */
+               if (!kmap_high_unmap_local(addr))
+                       WARN_ON_ONCE(addr < PAGE_OFFSET);
+               return;
+       }
+
+       preempt_disable();
+       idx = arch_kmap_local_unmap_idx(kmap_local_idx(), addr);
+       WARN_ON_ONCE(addr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
+
+       arch_kmap_local_pre_unmap(addr);
+       pte_clear(&init_mm, addr, kmap_pte - idx);
+       arch_kmap_local_post_unmap(addr);
+       current->kmap_ctrl.pteval[kmap_local_idx()] = __pte(0);
+       kmap_local_idx_pop();
+       preempt_enable();
+       migrate_enable();
+}
+EXPORT_SYMBOL(kunmap_local_indexed);
+
+/*
+ * Invoked before switch_to(). This is safe even when during or after
+ * clearing the maps an interrupt which needs a kmap_local happens because
+ * the task::kmap_ctrl.idx is not modified by the unmapping code so a
+ * nested kmap_local will use the next unused index and restore the index
+ * on unmap. The already cleared kmaps of the outgoing task are irrelevant
+ * because the interrupt context does not know about them. The same applies
+ * when scheduling back in for an interrupt which happens before the
+ * restore is complete.
+ */
+void __kmap_local_sched_out(void)
+{
+       struct task_struct *tsk = current;
+       pte_t *kmap_pte = kmap_get_pte();
+       int i;
+
+       /* Clear kmaps */
+       for (i = 0; i < tsk->kmap_ctrl.idx; i++) {
+               pte_t pteval = tsk->kmap_ctrl.pteval[i];
+               unsigned long addr;
+               int idx;
+
+               /* With debug all even slots are unmapped and act as guard */
+               if (IS_ENABLED(CONFIG_DEBUG_HIGHMEM) && !(i & 0x01)) {
+                       WARN_ON_ONCE(!pte_none(pteval));
+                       continue;
+               }
+               if (WARN_ON_ONCE(pte_none(pteval)))
+                       continue;
+
+               /*
+                * This is a horrible hack for XTENSA to calculate the
+                * coloured PTE index. Uses the PFN encoded into the pteval
+                * and the map index calculation because the actual mapped
+                * virtual address is not stored in task::kmap_ctrl.
+                * For any sane architecture this is optimized out.
+                */
+               idx = arch_kmap_local_map_idx(i, pte_pfn(pteval));
+
+               addr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+               arch_kmap_local_pre_unmap(addr);
+               pte_clear(&init_mm, addr, kmap_pte - idx);
+               arch_kmap_local_post_unmap(addr);
+       }
+}
+
+void __kmap_local_sched_in(void)
+{
+       struct task_struct *tsk = current;
+       pte_t *kmap_pte = kmap_get_pte();
+       int i;
+
+       /* Restore kmaps */
+       for (i = 0; i < tsk->kmap_ctrl.idx; i++) {
+               pte_t pteval = tsk->kmap_ctrl.pteval[i];
+               unsigned long addr;
+               int idx;
+
+               /* With debug all even slots are unmapped and act as guard */
+               if (IS_ENABLED(CONFIG_DEBUG_HIGHMEM) && !(i & 0x01)) {
+                       WARN_ON_ONCE(!pte_none(pteval));
+                       continue;
+               }
+               if (WARN_ON_ONCE(pte_none(pteval)))
+                       continue;
+
+               /* See comment in __kmap_local_sched_out() */
+               idx = arch_kmap_local_map_idx(i, pte_pfn(pteval));
+               addr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+               set_pte_at(&init_mm, addr, kmap_pte - idx, pteval);
+               arch_kmap_local_post_map(addr, pteval);
+       }
+}
+
+void kmap_local_fork(struct task_struct *tsk)
+{
+       if (WARN_ON_ONCE(tsk->kmap_ctrl.idx))
+               memset(&tsk->kmap_ctrl, 0, sizeof(tsk->kmap_ctrl));
+}
+
+#endif
 
 #if defined(HASHED_PAGE_VIRTUAL)
 
index db473e7..73ec4c1 100644 (file)
@@ -63,6 +63,7 @@
 #include <net/sock.h>
 #include <net/ip.h>
 #include "slab.h"
+#include <linux/local_lock.h>
 
 #include <linux/uaccess.h>
 
@@ -93,6 +94,13 @@ bool cgroup_memory_noswap __read_mostly;
 static DECLARE_WAIT_QUEUE_HEAD(memcg_cgwb_frn_waitq);
 #endif
 
+struct event_lock {
+       local_lock_t l;
+};
+static DEFINE_PER_CPU(struct event_lock, event_lock) = {
+       .l      = INIT_LOCAL_LOCK(l),
+};
+
 /* Whether legacy memory+swap accounting is active */
 static bool do_memsw_account(void)
 {
@@ -816,6 +824,7 @@ void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx,
        pn = container_of(lruvec, struct mem_cgroup_per_node, lruvec);
        memcg = pn->memcg;
 
+       preempt_disable_rt();
        /* Update memcg */
        __mod_memcg_state(memcg, idx, val);
 
@@ -835,6 +844,7 @@ void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx,
                x = 0;
        }
        __this_cpu_write(pn->lruvec_stat_cpu->count[idx], x);
+       preempt_enable_rt();
 }
 
 /**
@@ -2200,6 +2210,7 @@ void unlock_page_memcg(struct page *page)
 EXPORT_SYMBOL(unlock_page_memcg);
 
 struct memcg_stock_pcp {
+       local_lock_t lock;
        struct mem_cgroup *cached; /* this never be root cgroup */
        unsigned int nr_pages;
 
@@ -2251,7 +2262,7 @@ static bool consume_stock(struct mem_cgroup *memcg, unsigned int nr_pages)
        if (nr_pages > MEMCG_CHARGE_BATCH)
                return ret;
 
-       local_irq_save(flags);
+       local_lock_irqsave(&memcg_stock.lock, flags);
 
        stock = this_cpu_ptr(&memcg_stock);
        if (memcg == stock->cached && stock->nr_pages >= nr_pages) {
@@ -2259,7 +2270,7 @@ static bool consume_stock(struct mem_cgroup *memcg, unsigned int nr_pages)
                ret = true;
        }
 
-       local_irq_restore(flags);
+       local_unlock_irqrestore(&memcg_stock.lock, flags);
 
        return ret;
 }
@@ -2294,14 +2305,14 @@ static void drain_local_stock(struct work_struct *dummy)
         * The only protection from memory hotplug vs. drain_stock races is
         * that we always operate on local CPU stock here with IRQ disabled
         */
-       local_irq_save(flags);
+       local_lock_irqsave(&memcg_stock.lock, flags);
 
        stock = this_cpu_ptr(&memcg_stock);
        drain_obj_stock(stock);
        drain_stock(stock);
        clear_bit(FLUSHING_CACHED_CHARGE, &stock->flags);
 
-       local_irq_restore(flags);
+       local_unlock_irqrestore(&memcg_stock.lock, flags);
 }
 
 /*
@@ -2313,7 +2324,7 @@ static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages)
        struct memcg_stock_pcp *stock;
        unsigned long flags;
 
-       local_irq_save(flags);
+       local_lock_irqsave(&memcg_stock.lock, flags);
 
        stock = this_cpu_ptr(&memcg_stock);
        if (stock->cached != memcg) { /* reset if necessary */
@@ -2326,7 +2337,7 @@ static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages)
        if (stock->nr_pages > MEMCG_CHARGE_BATCH)
                drain_stock(stock);
 
-       local_irq_restore(flags);
+       local_unlock_irqrestore(&memcg_stock.lock, flags);
 }
 
 /*
@@ -2346,7 +2357,7 @@ static void drain_all_stock(struct mem_cgroup *root_memcg)
         * as well as workers from this path always operate on the local
         * per-cpu data. CPU up doesn't touch memcg_stock at all.
         */
-       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;
@@ -2369,7 +2380,7 @@ static void drain_all_stock(struct mem_cgroup *root_memcg)
                                schedule_work_on(cpu, &stock->work);
                }
        }
-       put_cpu();
+       put_cpu_light();
        mutex_unlock(&percpu_charge_mutex);
 }
 
@@ -3134,7 +3145,7 @@ static bool consume_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes)
        unsigned long flags;
        bool ret = false;
 
-       local_irq_save(flags);
+       local_lock_irqsave(&memcg_stock.lock, flags);
 
        stock = this_cpu_ptr(&memcg_stock);
        if (objcg == stock->cached_objcg && stock->nr_bytes >= nr_bytes) {
@@ -3142,7 +3153,7 @@ static bool consume_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes)
                ret = true;
        }
 
-       local_irq_restore(flags);
+       local_unlock_irqrestore(&memcg_stock.lock, flags);
 
        return ret;
 }
@@ -3209,7 +3220,7 @@ static void refill_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes)
        struct memcg_stock_pcp *stock;
        unsigned long flags;
 
-       local_irq_save(flags);
+       local_lock_irqsave(&memcg_stock.lock, flags);
 
        stock = this_cpu_ptr(&memcg_stock);
        if (stock->cached_objcg != objcg) { /* reset if necessary */
@@ -3223,7 +3234,7 @@ static void refill_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes)
        if (stock->nr_bytes > PAGE_SIZE)
                drain_obj_stock(stock);
 
-       local_irq_restore(flags);
+       local_unlock_irqrestore(&memcg_stock.lock, flags);
 }
 
 int obj_cgroup_charge(struct obj_cgroup *objcg, gfp_t gfp, size_t size)
@@ -5758,12 +5769,12 @@ static int mem_cgroup_move_account(struct page *page,
 
        ret = 0;
 
-       local_irq_disable();
+       local_lock_irq(&event_lock.l);
        mem_cgroup_charge_statistics(to, page, nr_pages);
        memcg_check_events(to, page);
        mem_cgroup_charge_statistics(from, page, -nr_pages);
        memcg_check_events(from, page);
-       local_irq_enable();
+       local_unlock_irq(&event_lock.l);
 out_unlock:
        unlock_page(page);
 out:
@@ -6833,10 +6844,10 @@ int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask)
        css_get(&memcg->css);
        commit_charge(page, memcg);
 
-       local_irq_disable();
+       local_lock_irq(&event_lock.l);
        mem_cgroup_charge_statistics(memcg, page, nr_pages);
        memcg_check_events(memcg, page);
-       local_irq_enable();
+       local_unlock_irq(&event_lock.l);
 
        /*
         * Cgroup1's unified memory+swap counter has been charged with the
@@ -6892,11 +6903,11 @@ static void uncharge_batch(const struct uncharge_gather *ug)
                memcg_oom_recover(ug->memcg);
        }
 
-       local_irq_save(flags);
+       local_lock_irqsave(&event_lock.l, flags);
        __count_memcg_events(ug->memcg, PGPGOUT, ug->pgpgout);
        __this_cpu_add(ug->memcg->vmstats_percpu->nr_page_events, ug->nr_pages);
        memcg_check_events(ug->memcg, ug->dummy_page);
-       local_irq_restore(flags);
+       local_unlock_irqrestore(&event_lock.l, flags);
 
        /* drop reference from uncharge_page */
        css_put(&ug->memcg->css);
@@ -7050,10 +7061,10 @@ void mem_cgroup_migrate(struct page *oldpage, struct page *newpage)
        css_get(&memcg->css);
        commit_charge(newpage, memcg);
 
-       local_irq_save(flags);
+       local_lock_irqsave(&event_lock.l, flags);
        mem_cgroup_charge_statistics(memcg, newpage, nr_pages);
        memcg_check_events(memcg, newpage);
-       local_irq_restore(flags);
+       local_unlock_irqrestore(&event_lock.l, flags);
 }
 
 DEFINE_STATIC_KEY_FALSE(memcg_sockets_enabled_key);
@@ -7173,9 +7184,13 @@ static int __init mem_cgroup_init(void)
        cpuhp_setup_state_nocalls(CPUHP_MM_MEMCQ_DEAD, "mm/memctrl:dead", NULL,
                                  memcg_hotplug_cpu_dead);
 
-       for_each_possible_cpu(cpu)
-               INIT_WORK(&per_cpu_ptr(&memcg_stock, cpu)->work,
-                         drain_local_stock);
+       for_each_possible_cpu(cpu) {
+               struct memcg_stock_pcp *stock;
+
+               stock = per_cpu_ptr(&memcg_stock, cpu);
+               INIT_WORK(&stock->work, drain_local_stock);
+               local_lock_init(&stock->lock);
+       }
 
        for_each_node(node) {
                struct mem_cgroup_tree_per_node *rtpn;
@@ -7224,6 +7239,7 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
        struct mem_cgroup *memcg, *swap_memcg;
        unsigned int nr_entries;
        unsigned short oldid;
+       unsigned long flags;
 
        VM_BUG_ON_PAGE(PageLRU(page), page);
        VM_BUG_ON_PAGE(page_count(page), page);
@@ -7269,9 +7285,13 @@ 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 updating the per-CPU variables.
         */
+       local_lock_irqsave(&event_lock.l, flags);
+#ifndef CONFIG_PREEMPT_RT
        VM_BUG_ON(!irqs_disabled());
+#endif
        mem_cgroup_charge_statistics(memcg, page, -nr_entries);
        memcg_check_events(memcg, page);
+       local_unlock_irqrestore(&event_lock.l, flags);
 
        css_put(&memcg->css);
 }
index 53e6be1..336e0da 100644 (file)
@@ -61,6 +61,7 @@
 #include <linux/hugetlb.h>
 #include <linux/sched/rt.h>
 #include <linux/sched/mm.h>
+#include <linux/local_lock.h>
 #include <linux/page_owner.h>
 #include <linux/kthread.h>
 #include <linux/memcontrol.h>
@@ -386,6 +387,13 @@ EXPORT_SYMBOL(nr_node_ids);
 EXPORT_SYMBOL(nr_online_nodes);
 #endif
 
+struct pa_lock {
+       local_lock_t l;
+};
+static DEFINE_PER_CPU(struct pa_lock, pa_lock) = {
+       .l      = INIT_LOCAL_LOCK(l),
+};
+
 int page_group_by_mobility_disabled __read_mostly;
 
 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
@@ -1331,7 +1339,7 @@ static inline void prefetch_buddy(struct page *page)
 }
 
 /*
- * 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.
  *
@@ -1341,15 +1349,56 @@ static inline void prefetch_buddy(struct page *page)
  * And clear the zone's pages_scanned counter, to hold off the "all pages are
  * pinned" detection logic.
  */
-static void free_pcppages_bulk(struct zone *zone, int count,
-                                       struct per_cpu_pages *pcp)
+static void free_pcppages_bulk(struct zone *zone, struct list_head *head,
+                              bool zone_retry)
+{
+       bool isolated_pageblocks;
+       struct page *page, *tmp;
+       unsigned long flags;
+
+       spin_lock_irqsave(&zone->lock, flags);
+       isolated_pageblocks = has_isolate_pageblock(zone);
+
+       /*
+        * Use safe version since after __free_one_page(),
+        * page->lru.next will not point to original list.
+        */
+       list_for_each_entry_safe(page, tmp, head, lru) {
+               int mt = get_pcppage_migratetype(page);
+
+               if (page_zone(page) != zone) {
+                       /*
+                        * free_unref_page_list() sorts pages by zone. If we end
+                        * up with pages from a different NUMA nodes belonging
+                        * to the same ZONE index then we need to redo with the
+                        * correct ZONE pointer. Skip the page for now, redo it
+                        * on the next iteration.
+                        */
+                       WARN_ON_ONCE(zone_retry == false);
+                       if (zone_retry)
+                               continue;
+               }
+
+               /* 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);
+
+               list_del(&page->lru);
+               __free_one_page(page, page_to_pfn(page), zone, 0, mt, FPI_NONE);
+               trace_mm_page_pcpu_drain(page, 0, mt);
+       }
+       spin_unlock_irqrestore(&zone->lock, flags);
+}
+
+static void isolate_pcp_pages(int count, struct per_cpu_pages *pcp,
+                             struct list_head *dst)
 {
        int migratetype = 0;
        int batch_free = 0;
        int prefetch_nr = 0;
-       bool isolated_pageblocks;
-       struct page *page, *tmp;
-       LIST_HEAD(head);
+       struct page *page;
 
        /*
         * Ensure proper count is passed which otherwise would stuck in the
@@ -1386,7 +1435,7 @@ static void free_pcppages_bulk(struct zone *zone, int count,
                        if (bulkfree_pcp_prepare(page))
                                continue;
 
-                       list_add_tail(&page->lru, &head);
+                       list_add_tail(&page->lru, dst);
 
                        /*
                         * We are going to put the page back to the global
@@ -1401,26 +1450,6 @@ static void free_pcppages_bulk(struct zone *zone, int count,
                                prefetch_buddy(page);
                } while (--count && --batch_free && !list_empty(list));
        }
-
-       spin_lock(&zone->lock);
-       isolated_pageblocks = has_isolate_pageblock(zone);
-
-       /*
-        * Use safe version since after __free_one_page(),
-        * page->lru.next will not point to original list.
-        */
-       list_for_each_entry_safe(page, tmp, &head, lru) {
-               int 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);
-
-               __free_one_page(page, page_to_pfn(page), zone, 0, mt, FPI_NONE);
-               trace_mm_page_pcpu_drain(page, 0, mt);
-       }
-       spin_unlock(&zone->lock);
 }
 
 static void free_one_page(struct zone *zone,
@@ -1522,11 +1551,11 @@ 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.l, flags);
        __count_vm_events(PGFREE, 1 << order);
        free_one_page(page_zone(page), page, pfn, order, migratetype,
                      fpi_flags);
-       local_irq_restore(flags);
+       local_unlock_irqrestore(&pa_lock.l, flags);
 }
 
 void __free_pages_core(struct page *page, unsigned int order)
@@ -2938,13 +2967,18 @@ void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp)
 {
        unsigned long flags;
        int to_drain, batch;
+       LIST_HEAD(dst);
 
-       local_irq_save(flags);
+       local_lock_irqsave(&pa_lock.l, flags);
        batch = READ_ONCE(pcp->batch);
        to_drain = min(pcp->count, batch);
        if (to_drain > 0)
-               free_pcppages_bulk(zone, to_drain, pcp);
-       local_irq_restore(flags);
+               isolate_pcp_pages(to_drain, pcp, &dst);
+
+       local_unlock_irqrestore(&pa_lock.l, flags);
+
+       if (to_drain > 0)
+               free_pcppages_bulk(zone, &dst, false);
 }
 #endif
 
@@ -2960,14 +2994,21 @@ 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);
+       local_lock_irqsave(&pa_lock.l, flags);
        pset = per_cpu_ptr(zone->pageset, cpu);
 
        pcp = &pset->pcp;
-       if (pcp->count)
-               free_pcppages_bulk(zone, pcp->count, pcp);
-       local_irq_restore(flags);
+       count = pcp->count;
+       if (count)
+               isolate_pcp_pages(count, pcp, &dst);
+
+       local_unlock_irqrestore(&pa_lock.l, flags);
+
+       if (count)
+               free_pcppages_bulk(zone, &dst, false);
 }
 
 /*
@@ -3015,9 +3056,9 @@ static void drain_local_pages_wq(struct work_struct *work)
         * cpu which is allright but we also have to make sure to not move to
         * a different one.
         */
-       preempt_disable();
+       migrate_disable();
        drain_local_pages(drain->zone);
-       preempt_enable();
+       migrate_enable();
 }
 
 /*
@@ -3166,7 +3207,8 @@ static bool free_unref_page_prepare(struct page *page, unsigned long pfn)
        return true;
 }
 
-static void free_unref_page_commit(struct page *page, unsigned long pfn)
+static void free_unref_page_commit(struct page *page, unsigned long pfn,
+                                  struct list_head *dst)
 {
        struct zone *zone = page_zone(page);
        struct per_cpu_pages *pcp;
@@ -3196,7 +3238,8 @@ static void free_unref_page_commit(struct page *page, unsigned long pfn)
        pcp->count++;
        if (pcp->count >= pcp->high) {
                unsigned long batch = READ_ONCE(pcp->batch);
-               free_pcppages_bulk(zone, batch, pcp);
+
+               isolate_pcp_pages(batch, pcp, dst);
        }
 }
 
@@ -3207,13 +3250,17 @@ void free_unref_page(struct page *page)
 {
        unsigned long flags;
        unsigned long pfn = page_to_pfn(page);
+       struct zone *zone = page_zone(page);
+       LIST_HEAD(dst);
 
        if (!free_unref_page_prepare(page, pfn))
                return;
 
-       local_irq_save(flags);
-       free_unref_page_commit(page, pfn);
-       local_irq_restore(flags);
+       local_lock_irqsave(&pa_lock.l, flags);
+       free_unref_page_commit(page, pfn, &dst);
+       local_unlock_irqrestore(&pa_lock.l, flags);
+       if (!list_empty(&dst))
+               free_pcppages_bulk(zone, &dst, false);
 }
 
 /*
@@ -3224,6 +3271,11 @@ void free_unref_page_list(struct list_head *list)
        struct page *page, *next;
        unsigned long flags, pfn;
        int batch_count = 0;
+       struct list_head dsts[__MAX_NR_ZONES];
+       int i;
+
+       for (i = 0; i < __MAX_NR_ZONES; i++)
+               INIT_LIST_HEAD(&dsts[i]);
 
        /* Prepare pages for freeing */
        list_for_each_entry_safe(page, next, list, lru) {
@@ -3233,25 +3285,42 @@ void free_unref_page_list(struct list_head *list)
                set_page_private(page, pfn);
        }
 
-       local_irq_save(flags);
+       local_lock_irqsave(&pa_lock.l, flags);
        list_for_each_entry_safe(page, next, list, lru) {
                unsigned long pfn = page_private(page);
+               enum zone_type type;
 
                set_page_private(page, 0);
                trace_mm_page_free_batched(page);
-               free_unref_page_commit(page, pfn);
+               type = page_zonenum(page);
+               free_unref_page_commit(page, pfn, &dsts[type]);
 
                /*
                 * Guard against excessive IRQ disabled times when we get
                 * a large list of pages to free.
                 */
                if (++batch_count == SWAP_CLUSTER_MAX) {
-                       local_irq_restore(flags);
+                       local_unlock_irqrestore(&pa_lock.l, flags);
                        batch_count = 0;
-                       local_irq_save(flags);
+                       local_lock_irqsave(&pa_lock.l, flags);
                }
        }
-       local_irq_restore(flags);
+       local_unlock_irqrestore(&pa_lock.l, flags);
+
+       for (i = 0; i < __MAX_NR_ZONES; ) {
+               struct page *page;
+               struct zone *zone;
+
+               if (list_empty(&dsts[i])) {
+                       i++;
+                       continue;
+               }
+
+               page = list_first_entry(&dsts[i], struct page, lru);
+               zone = page_zone(page);
+
+               free_pcppages_bulk(zone, &dsts[i], true);
+       }
 }
 
 /*
@@ -3407,7 +3476,7 @@ static struct page *rmqueue_pcplist(struct zone *preferred_zone,
        struct page *page;
        unsigned long flags;
 
-       local_irq_save(flags);
+       local_lock_irqsave(&pa_lock.l, flags);
        pcp = &this_cpu_ptr(zone->pageset)->pcp;
        list = &pcp->lists[migratetype];
        page = __rmqueue_pcplist(zone,  migratetype, alloc_flags, pcp, list);
@@ -3415,7 +3484,7 @@ static struct page *rmqueue_pcplist(struct zone *preferred_zone,
                __count_zid_vm_events(PGALLOC, page_zonenum(page), 1);
                zone_statistics(preferred_zone, zone);
        }
-       local_irq_restore(flags);
+       local_unlock_irqrestore(&pa_lock.l, flags);
        return page;
 }
 
@@ -3449,7 +3518,8 @@ struct page *rmqueue(struct zone *preferred_zone,
         * 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_lock_irqsave(&pa_lock.l, flags);
+       spin_lock(&zone->lock);
 
        do {
                page = NULL;
@@ -3475,7 +3545,7 @@ struct page *rmqueue(struct zone *preferred_zone,
 
        __count_zid_vm_events(PGALLOC, page_zonenum(page), 1 << order);
        zone_statistics(preferred_zone, zone);
-       local_irq_restore(flags);
+       local_unlock_irqrestore(&pa_lock.l, flags);
 
 out:
        /* Separate test+clear to avoid unnecessary atomics */
@@ -3488,7 +3558,7 @@ out:
        return page;
 
 failed:
-       local_irq_restore(flags);
+       local_unlock_irqrestore(&pa_lock.l, flags);
        return NULL;
 }
 
@@ -8763,7 +8833,7 @@ 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.l, flags);
        if (zone->pageset != &boot_pageset) {
                for_each_online_cpu(cpu) {
                        pset = per_cpu_ptr(zone->pageset, cpu);
@@ -8772,7 +8842,7 @@ void zone_pcp_reset(struct zone *zone)
                free_percpu(zone->pageset);
                zone->pageset = &boot_pageset;
        }
-       local_irq_restore(flags);
+       local_unlock_irqrestore(&pa_lock.l, flags);
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
index 67a8d5b..3d586b5 100644 (file)
@@ -278,10 +278,10 @@ static int shmem_reserve_inode(struct super_block *sb, ino_t *inop)
        ino_t ino;
 
        if (!(sb->s_flags & SB_KERNMOUNT)) {
-               spin_lock(&sbinfo->stat_lock);
+               raw_spin_lock(&sbinfo->stat_lock);
                if (sbinfo->max_inodes) {
                        if (!sbinfo->free_inodes) {
-                               spin_unlock(&sbinfo->stat_lock);
+                               raw_spin_unlock(&sbinfo->stat_lock);
                                return -ENOSPC;
                        }
                        sbinfo->free_inodes--;
@@ -304,7 +304,7 @@ static int shmem_reserve_inode(struct super_block *sb, ino_t *inop)
                        }
                        *inop = ino;
                }
-               spin_unlock(&sbinfo->stat_lock);
+               raw_spin_unlock(&sbinfo->stat_lock);
        } else if (inop) {
                /*
                 * __shmem_file_setup, one of our callers, is lock-free: it
@@ -319,13 +319,14 @@ static int shmem_reserve_inode(struct super_block *sb, ino_t *inop)
                 * to worry about things like glibc compatibility.
                 */
                ino_t *next_ino;
+
                next_ino = per_cpu_ptr(sbinfo->ino_batch, get_cpu());
                ino = *next_ino;
                if (unlikely(ino % SHMEM_INO_BATCH == 0)) {
-                       spin_lock(&sbinfo->stat_lock);
+                       raw_spin_lock(&sbinfo->stat_lock);
                        ino = sbinfo->next_ino;
                        sbinfo->next_ino += SHMEM_INO_BATCH;
-                       spin_unlock(&sbinfo->stat_lock);
+                       raw_spin_unlock(&sbinfo->stat_lock);
                        if (unlikely(is_zero_ino(ino)))
                                ino++;
                }
@@ -341,9 +342,9 @@ static void shmem_free_inode(struct super_block *sb)
 {
        struct shmem_sb_info *sbinfo = SHMEM_SB(sb);
        if (sbinfo->max_inodes) {
-               spin_lock(&sbinfo->stat_lock);
+               raw_spin_lock(&sbinfo->stat_lock);
                sbinfo->free_inodes++;
-               spin_unlock(&sbinfo->stat_lock);
+               raw_spin_unlock(&sbinfo->stat_lock);
        }
 }
 
@@ -1501,10 +1502,10 @@ static struct mempolicy *shmem_get_sbmpol(struct shmem_sb_info *sbinfo)
 {
        struct mempolicy *mpol = NULL;
        if (sbinfo->mpol) {
-               spin_lock(&sbinfo->stat_lock);  /* prevent replace/use races */
+               raw_spin_lock(&sbinfo->stat_lock);      /* prevent replace/use races */
                mpol = sbinfo->mpol;
                mpol_get(mpol);
-               spin_unlock(&sbinfo->stat_lock);
+               raw_spin_unlock(&sbinfo->stat_lock);
        }
        return mpol;
 }
@@ -3701,9 +3702,10 @@ static int shmem_reconfigure(struct fs_context *fc)
        struct shmem_options *ctx = fc->fs_private;
        struct shmem_sb_info *sbinfo = SHMEM_SB(fc->root->d_sb);
        unsigned long inodes;
+       struct mempolicy *mpol = NULL;
        const char *err;
 
-       spin_lock(&sbinfo->stat_lock);
+       raw_spin_lock(&sbinfo->stat_lock);
        inodes = sbinfo->max_inodes - sbinfo->free_inodes;
        if ((ctx->seen & SHMEM_SEEN_BLOCKS) && ctx->blocks) {
                if (!sbinfo->max_blocks) {
@@ -3748,14 +3750,15 @@ static int shmem_reconfigure(struct fs_context *fc)
         * Preserve previous mempolicy unless mpol remount option was specified.
         */
        if (ctx->mpol) {
-               mpol_put(sbinfo->mpol);
+               mpol = sbinfo->mpol;
                sbinfo->mpol = ctx->mpol;       /* transfers initial ref */
                ctx->mpol = NULL;
        }
-       spin_unlock(&sbinfo->stat_lock);
+       raw_spin_unlock(&sbinfo->stat_lock);
+       mpol_put(mpol);
        return 0;
 out:
-       spin_unlock(&sbinfo->stat_lock);
+       raw_spin_unlock(&sbinfo->stat_lock);
        return invalfc(fc, "%s", err);
 }
 
@@ -3872,7 +3875,7 @@ static int shmem_fill_super(struct super_block *sb, struct fs_context *fc)
        sbinfo->mpol = ctx->mpol;
        ctx->mpol = NULL;
 
-       spin_lock_init(&sbinfo->stat_lock);
+       raw_spin_lock_init(&sbinfo->stat_lock);
        if (percpu_counter_init(&sbinfo->used_blocks, 0, GFP_KERNEL))
                goto failed;
        spin_lock_init(&sbinfo->shrinklist_lock);
index b2cc2cf..677c065 100644 (file)
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -233,7 +233,7 @@ static void kmem_cache_node_init(struct kmem_cache_node *parent)
        parent->shared = NULL;
        parent->alien = NULL;
        parent->colour_next = 0;
-       spin_lock_init(&parent->list_lock);
+       raw_spin_lock_init(&parent->list_lock);
        parent->free_objects = 0;
        parent->free_touched = 0;
 }
@@ -558,9 +558,9 @@ static noinline void cache_free_pfmemalloc(struct kmem_cache *cachep,
        page_node = page_to_nid(page);
        n = get_node(cachep, page_node);
 
-       spin_lock(&n->list_lock);
+       raw_spin_lock(&n->list_lock);
        free_block(cachep, &objp, 1, page_node, &list);
-       spin_unlock(&n->list_lock);
+       raw_spin_unlock(&n->list_lock);
 
        slabs_destroy(cachep, &list);
 }
@@ -698,7 +698,7 @@ static void __drain_alien_cache(struct kmem_cache *cachep,
        struct kmem_cache_node *n = get_node(cachep, node);
 
        if (ac->avail) {
-               spin_lock(&n->list_lock);
+               raw_spin_lock(&n->list_lock);
                /*
                 * Stuff objects into the remote nodes shared array first.
                 * That way we could avoid the overhead of putting the objects
@@ -709,7 +709,7 @@ static void __drain_alien_cache(struct kmem_cache *cachep,
 
                free_block(cachep, ac->entry, ac->avail, node, list);
                ac->avail = 0;
-               spin_unlock(&n->list_lock);
+               raw_spin_unlock(&n->list_lock);
        }
 }
 
@@ -782,9 +782,9 @@ static int __cache_free_alien(struct kmem_cache *cachep, void *objp,
                slabs_destroy(cachep, &list);
        } else {
                n = get_node(cachep, page_node);
-               spin_lock(&n->list_lock);
+               raw_spin_lock(&n->list_lock);
                free_block(cachep, &objp, 1, page_node, &list);
-               spin_unlock(&n->list_lock);
+               raw_spin_unlock(&n->list_lock);
                slabs_destroy(cachep, &list);
        }
        return 1;
@@ -825,10 +825,10 @@ static int init_cache_node(struct kmem_cache *cachep, int node, gfp_t gfp)
         */
        n = get_node(cachep, node);
        if (n) {
-               spin_lock_irq(&n->list_lock);
+               raw_spin_lock_irq(&n->list_lock);
                n->free_limit = (1 + nr_cpus_node(node)) * cachep->batchcount +
                                cachep->num;
-               spin_unlock_irq(&n->list_lock);
+               raw_spin_unlock_irq(&n->list_lock);
 
                return 0;
        }
@@ -907,7 +907,7 @@ static int setup_kmem_cache_node(struct kmem_cache *cachep,
                goto fail;
 
        n = get_node(cachep, node);
-       spin_lock_irq(&n->list_lock);
+       raw_spin_lock_irq(&n->list_lock);
        if (n->shared && force_change) {
                free_block(cachep, n->shared->entry,
                                n->shared->avail, node, &list);
@@ -925,7 +925,7 @@ static int setup_kmem_cache_node(struct kmem_cache *cachep,
                new_alien = NULL;
        }
 
-       spin_unlock_irq(&n->list_lock);
+       raw_spin_unlock_irq(&n->list_lock);
        slabs_destroy(cachep, &list);
 
        /*
@@ -964,7 +964,7 @@ static void cpuup_canceled(long cpu)
                if (!n)
                        continue;
 
-               spin_lock_irq(&n->list_lock);
+               raw_spin_lock_irq(&n->list_lock);
 
                /* Free limit for this kmem_cache_node */
                n->free_limit -= cachep->batchcount;
@@ -975,7 +975,7 @@ static void cpuup_canceled(long cpu)
                nc->avail = 0;
 
                if (!cpumask_empty(mask)) {
-                       spin_unlock_irq(&n->list_lock);
+                       raw_spin_unlock_irq(&n->list_lock);
                        goto free_slab;
                }
 
@@ -989,7 +989,7 @@ static void cpuup_canceled(long cpu)
                alien = n->alien;
                n->alien = NULL;
 
-               spin_unlock_irq(&n->list_lock);
+               raw_spin_unlock_irq(&n->list_lock);
 
                kfree(shared);
                if (alien) {
@@ -1173,7 +1173,7 @@ static void __init init_list(struct kmem_cache *cachep, struct kmem_cache_node *
        /*
         * Do not assume that spinlocks can be initialized via memcpy:
         */
-       spin_lock_init(&ptr->list_lock);
+       raw_spin_lock_init(&ptr->list_lock);
 
        MAKE_ALL_LISTS(cachep, ptr, nodeid);
        cachep->node[nodeid] = ptr;
@@ -1344,11 +1344,11 @@ slab_out_of_memory(struct kmem_cache *cachep, gfp_t gfpflags, int nodeid)
        for_each_kmem_cache_node(cachep, node, n) {
                unsigned long total_slabs, free_slabs, free_objs;
 
-               spin_lock_irqsave(&n->list_lock, flags);
+               raw_spin_lock_irqsave(&n->list_lock, flags);
                total_slabs = n->total_slabs;
                free_slabs = n->free_slabs;
                free_objs = n->free_objects;
-               spin_unlock_irqrestore(&n->list_lock, flags);
+               raw_spin_unlock_irqrestore(&n->list_lock, flags);
 
                pr_warn("  node %d: slabs: %ld/%ld, objs: %ld/%ld\n",
                        node, total_slabs - free_slabs, total_slabs,
@@ -2105,7 +2105,7 @@ static void check_spinlock_acquired(struct kmem_cache *cachep)
 {
 #ifdef CONFIG_SMP
        check_irq_off();
-       assert_spin_locked(&get_node(cachep, numa_mem_id())->list_lock);
+       assert_raw_spin_locked(&get_node(cachep, numa_mem_id())->list_lock);
 #endif
 }
 
@@ -2113,7 +2113,7 @@ static void check_spinlock_acquired_node(struct kmem_cache *cachep, int node)
 {
 #ifdef CONFIG_SMP
        check_irq_off();
-       assert_spin_locked(&get_node(cachep, node)->list_lock);
+       assert_raw_spin_locked(&get_node(cachep, node)->list_lock);
 #endif
 }
 
@@ -2153,9 +2153,9 @@ static void do_drain(void *arg)
        check_irq_off();
        ac = cpu_cache_get(cachep);
        n = get_node(cachep, node);
-       spin_lock(&n->list_lock);
+       raw_spin_lock(&n->list_lock);
        free_block(cachep, ac->entry, ac->avail, node, &list);
-       spin_unlock(&n->list_lock);
+       raw_spin_unlock(&n->list_lock);
        ac->avail = 0;
        slabs_destroy(cachep, &list);
 }
@@ -2173,9 +2173,9 @@ static void drain_cpu_caches(struct kmem_cache *cachep)
                        drain_alien_cache(cachep, n->alien);
 
        for_each_kmem_cache_node(cachep, node, n) {
-               spin_lock_irq(&n->list_lock);
+               raw_spin_lock_irq(&n->list_lock);
                drain_array_locked(cachep, n->shared, node, true, &list);
-               spin_unlock_irq(&n->list_lock);
+               raw_spin_unlock_irq(&n->list_lock);
 
                slabs_destroy(cachep, &list);
        }
@@ -2197,10 +2197,10 @@ static int drain_freelist(struct kmem_cache *cache,
        nr_freed = 0;
        while (nr_freed < tofree && !list_empty(&n->slabs_free)) {
 
-               spin_lock_irq(&n->list_lock);
+               raw_spin_lock_irq(&n->list_lock);
                p = n->slabs_free.prev;
                if (p == &n->slabs_free) {
-                       spin_unlock_irq(&n->list_lock);
+                       raw_spin_unlock_irq(&n->list_lock);
                        goto out;
                }
 
@@ -2213,7 +2213,7 @@ static int drain_freelist(struct kmem_cache *cache,
                 * to the cache.
                 */
                n->free_objects -= cache->num;
-               spin_unlock_irq(&n->list_lock);
+               raw_spin_unlock_irq(&n->list_lock);
                slab_destroy(cache, page);
                nr_freed++;
        }
@@ -2649,7 +2649,7 @@ static void cache_grow_end(struct kmem_cache *cachep, struct page *page)
        INIT_LIST_HEAD(&page->slab_list);
        n = get_node(cachep, page_to_nid(page));
 
-       spin_lock(&n->list_lock);
+       raw_spin_lock(&n->list_lock);
        n->total_slabs++;
        if (!page->active) {
                list_add_tail(&page->slab_list, &n->slabs_free);
@@ -2659,7 +2659,7 @@ static void cache_grow_end(struct kmem_cache *cachep, struct page *page)
 
        STATS_INC_GROWN(cachep);
        n->free_objects += cachep->num - page->active;
-       spin_unlock(&n->list_lock);
+       raw_spin_unlock(&n->list_lock);
 
        fixup_objfreelist_debug(cachep, &list);
 }
@@ -2825,7 +2825,7 @@ static struct page *get_first_slab(struct kmem_cache_node *n, bool pfmemalloc)
 {
        struct page *page;
 
-       assert_spin_locked(&n->list_lock);
+       assert_raw_spin_locked(&n->list_lock);
        page = list_first_entry_or_null(&n->slabs_partial, struct page,
                                        slab_list);
        if (!page) {
@@ -2852,10 +2852,10 @@ static noinline void *cache_alloc_pfmemalloc(struct kmem_cache *cachep,
        if (!gfp_pfmemalloc_allowed(flags))
                return NULL;
 
-       spin_lock(&n->list_lock);
+       raw_spin_lock(&n->list_lock);
        page = get_first_slab(n, true);
        if (!page) {
-               spin_unlock(&n->list_lock);
+               raw_spin_unlock(&n->list_lock);
                return NULL;
        }
 
@@ -2864,7 +2864,7 @@ static noinline void *cache_alloc_pfmemalloc(struct kmem_cache *cachep,
 
        fixup_slab_list(cachep, n, page, &list);
 
-       spin_unlock(&n->list_lock);
+       raw_spin_unlock(&n->list_lock);
        fixup_objfreelist_debug(cachep, &list);
 
        return obj;
@@ -2923,7 +2923,7 @@ static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags)
        if (!n->free_objects && (!shared || !shared->avail))
                goto direct_grow;
 
-       spin_lock(&n->list_lock);
+       raw_spin_lock(&n->list_lock);
        shared = READ_ONCE(n->shared);
 
        /* See if we can refill from the shared array */
@@ -2947,7 +2947,7 @@ static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags)
 must_grow:
        n->free_objects -= ac->avail;
 alloc_done:
-       spin_unlock(&n->list_lock);
+       raw_spin_unlock(&n->list_lock);
        fixup_objfreelist_debug(cachep, &list);
 
 direct_grow:
@@ -3172,7 +3172,7 @@ static void *____cache_alloc_node(struct kmem_cache *cachep, gfp_t flags,
        BUG_ON(!n);
 
        check_irq_off();
-       spin_lock(&n->list_lock);
+       raw_spin_lock(&n->list_lock);
        page = get_first_slab(n, false);
        if (!page)
                goto must_grow;
@@ -3190,12 +3190,12 @@ static void *____cache_alloc_node(struct kmem_cache *cachep, gfp_t flags,
 
        fixup_slab_list(cachep, n, page, &list);
 
-       spin_unlock(&n->list_lock);
+       raw_spin_unlock(&n->list_lock);
        fixup_objfreelist_debug(cachep, &list);
        return obj;
 
 must_grow:
-       spin_unlock(&n->list_lock);
+       raw_spin_unlock(&n->list_lock);
        page = cache_grow_begin(cachep, gfp_exact_node(flags), nodeid);
        if (page) {
                /* This slab isn't counted yet so don't update free_objects */
@@ -3373,7 +3373,7 @@ static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac)
 
        check_irq_off();
        n = get_node(cachep, node);
-       spin_lock(&n->list_lock);
+       raw_spin_lock(&n->list_lock);
        if (n->shared) {
                struct array_cache *shared_array = n->shared;
                int max = shared_array->limit - shared_array->avail;
@@ -3402,7 +3402,7 @@ free_done:
                STATS_SET_FREEABLE(cachep, i);
        }
 #endif
-       spin_unlock(&n->list_lock);
+       raw_spin_unlock(&n->list_lock);
        ac->avail -= batchcount;
        memmove(ac->entry, &(ac->entry[batchcount]), sizeof(void *)*ac->avail);
        slabs_destroy(cachep, &list);
@@ -3831,9 +3831,9 @@ static int do_tune_cpucache(struct kmem_cache *cachep, int limit,
 
                node = cpu_to_mem(cpu);
                n = get_node(cachep, node);
-               spin_lock_irq(&n->list_lock);
+               raw_spin_lock_irq(&n->list_lock);
                free_block(cachep, ac->entry, ac->avail, node, &list);
-               spin_unlock_irq(&n->list_lock);
+               raw_spin_unlock_irq(&n->list_lock);
                slabs_destroy(cachep, &list);
        }
        free_percpu(prev);
@@ -3928,9 +3928,9 @@ static void drain_array(struct kmem_cache *cachep, struct kmem_cache_node *n,
                return;
        }
 
-       spin_lock_irq(&n->list_lock);
+       raw_spin_lock_irq(&n->list_lock);
        drain_array_locked(cachep, ac, node, false, &list);
-       spin_unlock_irq(&n->list_lock);
+       raw_spin_unlock_irq(&n->list_lock);
 
        slabs_destroy(cachep, &list);
 }
@@ -4014,7 +4014,7 @@ void get_slabinfo(struct kmem_cache *cachep, struct slabinfo *sinfo)
 
        for_each_kmem_cache_node(cachep, node, n) {
                check_irq_on();
-               spin_lock_irq(&n->list_lock);
+               raw_spin_lock_irq(&n->list_lock);
 
                total_slabs += n->total_slabs;
                free_slabs += n->free_slabs;
@@ -4023,7 +4023,7 @@ void get_slabinfo(struct kmem_cache *cachep, struct slabinfo *sinfo)
                if (n->shared)
                        shared_avail += n->shared->avail;
 
-               spin_unlock_irq(&n->list_lock);
+               raw_spin_unlock_irq(&n->list_lock);
        }
        num_objs = total_slabs * cachep->num;
        active_slabs = total_slabs - free_slabs;
index 6952e10..ed5dd6e 100644 (file)
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -543,7 +543,7 @@ static inline void slab_post_alloc_hook(struct kmem_cache *s,
  * The slab lists for all objects.
  */
 struct kmem_cache_node {
-       spinlock_t list_lock;
+       raw_spinlock_t list_lock;
 
 #ifdef CONFIG_SLAB
        struct list_head slabs_partial; /* partial list first, better asm code */
index 1384dc9..d90d8f9 100644 (file)
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -435,7 +435,7 @@ static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct page *page,
 
 #ifdef CONFIG_SLUB_DEBUG
 static unsigned long object_map[BITS_TO_LONGS(MAX_OBJS_PER_PAGE)];
-static DEFINE_SPINLOCK(object_map_lock);
+static DEFINE_RAW_SPINLOCK(object_map_lock);
 
 /*
  * Determine a map of object in use on a page.
@@ -451,7 +451,7 @@ static unsigned long *get_map(struct kmem_cache *s, struct page *page)
 
        VM_BUG_ON(!irqs_disabled());
 
-       spin_lock(&object_map_lock);
+       raw_spin_lock(&object_map_lock);
 
        bitmap_zero(object_map, page->objects);
 
@@ -464,7 +464,7 @@ static unsigned long *get_map(struct kmem_cache *s, struct page *page)
 static void put_map(unsigned long *map) __releases(&object_map_lock)
 {
        VM_BUG_ON(map != object_map);
-       spin_unlock(&object_map_lock);
+       raw_spin_unlock(&object_map_lock);
 }
 
 static inline unsigned int size_from_object(struct kmem_cache *s)
@@ -1214,7 +1214,7 @@ static noinline int free_debug_processing(
        unsigned long 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) {
@@ -1249,7 +1249,7 @@ 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;
@@ -1494,6 +1494,12 @@ 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.
@@ -1744,10 +1750,18 @@ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)
        void *start, *p, *next;
        int idx;
        bool shuffle;
+       bool enableirqs = false;
 
        flags &= gfp_allowed_mask;
 
        if (gfpflags_allow_blocking(flags))
+               enableirqs = true;
+
+#ifdef CONFIG_PREEMPT_RT
+       if (system_state > SYSTEM_BOOTING && system_state < SYSTEM_SUSPEND)
+               enableirqs = true;
+#endif
+       if (enableirqs)
                local_irq_enable();
 
        flags |= s->allocflags;
@@ -1806,7 +1820,7 @@ 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;
@@ -1849,6 +1863,16 @@ 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);
+       }
+}
+
 static void rcu_free_slab(struct rcu_head *h)
 {
        struct page *page = container_of(h, struct page, rcu_head);
@@ -1860,6 +1884,12 @@ static void free_slab(struct kmem_cache *s, struct page *page)
 {
        if (unlikely(s->flags & SLAB_TYPESAFE_BY_RCU)) {
                call_rcu(&page->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);
 }
@@ -1967,7 +1997,7 @@ 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, slab_list) {
                void *t;
 
@@ -1992,7 +2022,7 @@ 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;
 }
 
@@ -2246,7 +2276,7 @@ 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;
@@ -2258,7 +2288,7 @@ redo:
                         * slabs from diagnostic functions will not see
                         * any frozen slabs.
                         */
-                       spin_lock(&n->list_lock);
+                       raw_spin_lock(&n->list_lock);
                }
 #endif
        }
@@ -2283,7 +2313,7 @@ redo:
                goto redo;
 
        if (lock)
-               spin_unlock(&n->list_lock);
+               raw_spin_unlock(&n->list_lock);
 
        if (m == M_PARTIAL)
                stat(s, tail);
@@ -2322,10 +2352,10 @@ 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 {
@@ -2354,7 +2384,7 @@ 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;
@@ -2391,14 +2421,21 @@ static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain)
                        pobjects = oldpage->pobjects;
                        pages = oldpage->pages;
                        if (drain && pobjects > slub_cpu_partial(s)) {
+                               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;
@@ -2466,7 +2503,19 @@ 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);
+       for_each_online_cpu(cpu) {
+               struct slub_free_list *f;
+
+               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);
+       }
 }
 
 /*
@@ -2521,10 +2570,10 @@ 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, slab_list)
                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 */
@@ -2663,8 +2712,10 @@ 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;
 
@@ -2732,6 +2783,13 @@ load_freelist:
        VM_BUG_ON(!c->page->frozen);
        c->freelist = get_freepointer(s, freelist);
        c->tid = next_tid(c->tid);
+
+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:
@@ -2747,7 +2805,7 @@ new_slab:
 
        if (unlikely(!freelist)) {
                slab_out_of_memory(s, gfpflags, node);
-               return NULL;
+               goto out;
        }
 
        page = c->page;
@@ -2760,7 +2818,7 @@ new_slab:
                goto new_slab;  /* Slab failed checks. Next slab needed */
 
        deactivate_slab(s, page, get_freepointer(s, freelist), c);
-       return freelist;
+       goto out;
 }
 
 /*
@@ -2772,6 +2830,7 @@ 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_PREEMPTION
@@ -2783,8 +2842,9 @@ 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;
 }
 
@@ -2818,6 +2878,10 @@ static __always_inline void *slab_alloc_node(struct kmem_cache *s,
        unsigned long tid;
        struct obj_cgroup *objcg = NULL;
 
+       if (IS_ENABLED(CONFIG_PREEMPT_RT) && IS_ENABLED(CONFIG_DEBUG_ATOMIC_SLEEP))
+               WARN_ON_ONCE(!preemptible() &&
+                            (system_state > SYSTEM_BOOTING && system_state < SYSTEM_SUSPEND));
+
        s = slab_pre_alloc_hook(s, &objcg, 1, gfpflags);
        if (!s)
                return NULL;
@@ -2983,7 +3047,7 @@ 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;
@@ -3015,7 +3079,7 @@ 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);
 
                        }
                }
@@ -3057,7 +3121,7 @@ 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:
@@ -3072,7 +3136,7 @@ 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);
 }
@@ -3282,9 +3346,14 @@ 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;
        struct obj_cgroup *objcg = NULL;
 
+       if (IS_ENABLED(CONFIG_PREEMPT_RT) && IS_ENABLED(CONFIG_DEBUG_ATOMIC_SLEEP))
+               WARN_ON_ONCE(!preemptible() &&
+                            (system_state > SYSTEM_BOOTING && system_state < SYSTEM_SUSPEND));
+
        /* memcg and kmem_cache debug support */
        s = slab_pre_alloc_hook(s, &objcg, size, flags);
        if (unlikely(!s))
@@ -3315,7 +3384,7 @@ 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;
 
@@ -3330,6 +3399,7 @@ 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(slab_want_init_on_alloc(flags, s))) {
@@ -3344,6 +3414,7 @@ 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, objcg, flags, i, p);
        __kmem_cache_free_bulk(s, i, p);
        return 0;
@@ -3479,7 +3550,7 @@ 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);
@@ -3874,7 +3945,7 @@ 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, slab_list) {
                if (!page->inuse) {
                        remove_partial(n, page);
@@ -3884,7 +3955,7 @@ 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, slab_list)
                discard_slab(s, page);
@@ -4155,7 +4226,7 @@ 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.
@@ -4186,7 +4257,7 @@ 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, slab_list)
@@ -4361,6 +4432,12 @@ 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;
@@ -4548,7 +4625,7 @@ 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, slab_list) {
                validate_slab(s, page);
@@ -4570,7 +4647,7 @@ 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;
 }
 
@@ -4621,6 +4698,9 @@ static int alloc_loc_track(struct loc_track *t, unsigned long max, gfp_t flags)
        struct location *l;
        int order;
 
+       if (IS_ENABLED(CONFIG_PREEMPT_RT) && flags == GFP_ATOMIC)
+               return 0;
+
        order = get_order(sizeof(struct location) * max);
 
        l = (void *)__get_free_pages(flags, order);
@@ -4749,12 +4829,12 @@ 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, slab_list)
                        process_slab(&t, s, page, alloc);
                list_for_each_entry(page, &n->full, slab_list)
                        process_slab(&t, s, page, alloc);
-               spin_unlock_irqrestore(&n->list_lock, flags);
+               raw_spin_unlock_irqrestore(&n->list_lock, flags);
        }
 
        for (i = 0; i < t.count; i++) {
index fff03a3..2cbbbdb 100644 (file)
@@ -1542,7 +1542,7 @@ 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();
@@ -1579,11 +1579,12 @@ static void *new_vmap_block(unsigned int order, gfp_t gfp_mask)
                return ERR_PTR(err);
        }
 
-       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;
 }
@@ -1648,6 +1649,7 @@ 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);
@@ -1662,7 +1664,8 @@ 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;
 
@@ -1685,7 +1688,7 @@ 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 feb65b0..c43f83c 100644 (file)
@@ -321,6 +321,7 @@ 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);
@@ -330,6 +331,7 @@ 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);
 
@@ -346,6 +348,7 @@ void __mod_node_page_state(struct pglist_data *pgdat, enum node_stat_item item,
                delta >>= PAGE_SHIFT;
        }
 
+       preempt_disable_rt();
        x = delta + __this_cpu_read(*p);
 
        t = __this_cpu_read(pcp->stat_threshold);
@@ -355,6 +358,7 @@ 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);
 
@@ -387,6 +391,7 @@ 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)) {
@@ -395,6 +400,7 @@ 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)
@@ -405,6 +411,7 @@ void __inc_node_state(struct pglist_data *pgdat, enum node_stat_item item)
 
        VM_WARN_ON_ONCE(vmstat_item_in_bytes(item));
 
+       preempt_disable_rt();
        v = __this_cpu_inc_return(*p);
        t = __this_cpu_read(pcp->stat_threshold);
        if (unlikely(v > t)) {
@@ -413,6 +420,7 @@ 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)
@@ -433,6 +441,7 @@ 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)) {
@@ -441,6 +450,7 @@ 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)
@@ -451,6 +461,7 @@ void __dec_node_state(struct pglist_data *pgdat, enum node_stat_item item)
 
        VM_WARN_ON_ONCE(vmstat_item_in_bytes(item));
 
+       preempt_disable_rt();
        v = __this_cpu_dec_return(*p);
        t = __this_cpu_read(pcp->stat_threshold);
        if (unlikely(v < - t)) {
@@ -459,6 +470,7 @@ 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 975a4d2..c3d098c 100644 (file)
@@ -432,6 +432,8 @@ static struct list_lru shadow_nodes;
 
 void workingset_update_node(struct xa_node *node)
 {
+       struct address_space *mapping;
+
        /*
         * Track non-empty nodes that contain only shadow entries;
         * unlink those that contain pages or are being freed.
@@ -440,7 +442,8 @@ void workingset_update_node(struct xa_node *node)
         * already where they should be. The list_empty() test is safe
         * as node->private_list is protected by the i_pages lock.
         */
-       VM_WARN_ON_ONCE(!irqs_disabled());  /* For __inc_lruvec_page_state */
+       mapping = container_of(node->array, struct address_space, i_pages);
+       lockdep_assert_held(&mapping->i_pages.xa_lock);
 
        if (node->count && node->count == node->nr_values) {
                if (list_empty(&node->private_list)) {
index 912ac9a..f3d875f 100644 (file)
@@ -623,14 +623,16 @@ static inline void add_to_unbuddied(struct z3fold_pool *pool,
 {
        if (zhdr->first_chunks == 0 || zhdr->last_chunks == 0 ||
                        zhdr->middle_chunks == 0) {
-               struct list_head *unbuddied = get_cpu_ptr(pool->unbuddied);
-
+               struct list_head *unbuddied;
                int freechunks = num_free_chunks(zhdr);
+
+               migrate_disable();
+               unbuddied = this_cpu_ptr(pool->unbuddied);
                spin_lock(&pool->lock);
                list_add(&zhdr->buddy, &unbuddied[freechunks]);
                spin_unlock(&pool->lock);
                zhdr->cpu = smp_processor_id();
-               put_cpu_ptr(pool->unbuddied);
+               migrate_enable();
        }
 }
 
@@ -880,8 +882,9 @@ static inline struct z3fold_header *__z3fold_alloc(struct z3fold_pool *pool,
        int chunks = size_to_chunks(size), i;
 
 lookup:
+       migrate_disable();
        /* First, try to find an unbuddied z3fold page. */
-       unbuddied = get_cpu_ptr(pool->unbuddied);
+       unbuddied = this_cpu_ptr(pool->unbuddied);
        for_each_unbuddied_list(i, chunks) {
                struct list_head *l = &unbuddied[i];
 
@@ -899,7 +902,7 @@ lookup:
                    !z3fold_page_trylock(zhdr)) {
                        spin_unlock(&pool->lock);
                        zhdr = NULL;
-                       put_cpu_ptr(pool->unbuddied);
+                       migrate_enable();
                        if (can_sleep)
                                cond_resched();
                        goto lookup;
@@ -913,7 +916,7 @@ lookup:
                    test_bit(PAGE_CLAIMED, &page->private)) {
                        z3fold_page_unlock(zhdr);
                        zhdr = NULL;
-                       put_cpu_ptr(pool->unbuddied);
+                       migrate_enable();
                        if (can_sleep)
                                cond_resched();
                        goto lookup;
@@ -928,7 +931,7 @@ lookup:
                kref_get(&zhdr->refcount);
                break;
        }
-       put_cpu_ptr(pool->unbuddied);
+       migrate_enable();
 
        if (!zhdr) {
                int cpu;
index 73cd507..142170f 100644 (file)
@@ -57,6 +57,7 @@
 #include <linux/wait.h>
 #include <linux/pagemap.h>
 #include <linux/fs.h>
+#include <linux/local_lock.h>
 
 #define ZSPAGE_MAGIC   0x58
 
 
 #define ZS_HANDLE_SIZE (sizeof(unsigned long))
 
+#ifdef CONFIG_PREEMPT_RT
+
+struct zsmalloc_handle {
+       unsigned long addr;
+       spinlock_t 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
  * a single (unsigned long) handle value.
@@ -293,6 +308,7 @@ struct zspage {
 };
 
 struct mapping_area {
+       local_lock_t lock;
        char *vm_buf; /* copy buffer for objects that span pages */
        char *vm_addr; /* address of kmap_atomic()'ed pages */
        enum zs_mapmode vm_mm; /* mapping mode */
@@ -322,7 +338,7 @@ 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;
@@ -346,10 +362,27 @@ 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
+       if (p) {
+               struct zsmalloc_handle *zh = p;
+
+               spin_lock_init(&zh->lock);
+       }
+#endif
+       return (unsigned long)p;
 }
 
+#ifdef CONFIG_PREEMPT_RT
+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);
@@ -368,12 +401,18 @@ 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
+       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 */
@@ -455,7 +494,10 @@ MODULE_ALIAS("zpool-zsmalloc");
 #endif /* CONFIG_ZPOOL */
 
 /* per-cpu VM mapping areas for zspage accesses that cross page boundaries */
-static DEFINE_PER_CPU(struct mapping_area, zs_map_area);
+static DEFINE_PER_CPU(struct mapping_area, zs_map_area) = {
+       /* XXX remove this and use a spin_lock_t in pin_tag() */
+       .lock   = INIT_LOCAL_LOCK(lock),
+};
 
 static bool is_zspage_isolated(struct zspage *zspage)
 {
@@ -865,7 +907,13 @@ 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
+       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)
@@ -879,22 +927,46 @@ static unsigned long obj_to_head(struct page *page, void *obj)
 
 static inline int testpin_tag(unsigned long handle)
 {
+#ifdef CONFIG_PREEMPT_RT
+       struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+       return spin_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
+       struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+       return spin_trylock(&zh->lock);
+#else
        return bit_spin_trylock(HANDLE_PIN_BIT, (unsigned long *)handle);
+#endif
 }
 
 static void pin_tag(unsigned long handle) __acquires(bitlock)
 {
+#ifdef CONFIG_PREEMPT_RT
+       struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+       return spin_lock(&zh->lock);
+#else
        bit_spin_lock(HANDLE_PIN_BIT, (unsigned long *)handle);
+#endif
 }
 
 static void unpin_tag(unsigned long handle) __releases(bitlock)
 {
+#ifdef CONFIG_PREEMPT_RT
+       struct zsmalloc_handle *zh = zs_get_pure_handle(handle);
+
+       return spin_unlock(&zh->lock);
+#else
        bit_spin_unlock(HANDLE_PIN_BIT, (unsigned long *)handle);
+#endif
 }
 
 static void reset_page(struct page *page)
@@ -1278,7 +1350,8 @@ 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);
+       local_lock(&zs_map_area.lock);
+       area = this_cpu_ptr(&zs_map_area);
        area->vm_mm = mm;
        if (off + class->size <= PAGE_SIZE) {
                /* this object is contained entirely within a page */
@@ -1332,7 +1405,7 @@ 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);
+       local_unlock(&zs_map_area.lock);
 
        migrate_read_unlock(zspage);
        unpin_tag(handle);
index 0ca7f6a..6463fac 100644 (file)
@@ -18,6 +18,7 @@
 #include <linux/highmem.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
+#include <linux/local_lock.h>
 #include <linux/types.h>
 #include <linux/atomic.h>
 #include <linux/frontswap.h>
@@ -387,27 +388,37 @@ static struct zswap_entry *zswap_entry_find_get(struct rb_root *root,
 /*********************************
 * per-cpu code
 **********************************/
-static DEFINE_PER_CPU(u8 *, zswap_dstmem);
+struct zswap_comp {
+       /* Used for per-CPU dstmem and tfm */
+       local_lock_t lock;
+       u8 *dstmem;
+};
+
+static DEFINE_PER_CPU(struct zswap_comp, zswap_comp) = {
+       .lock = INIT_LOCAL_LOCK(lock),
+};
 
 static int zswap_dstmem_prepare(unsigned int cpu)
 {
+       struct zswap_comp *zcomp;
        u8 *dst;
 
        dst = kmalloc_node(PAGE_SIZE * 2, GFP_KERNEL, cpu_to_node(cpu));
        if (!dst)
                return -ENOMEM;
 
-       per_cpu(zswap_dstmem, cpu) = dst;
+       zcomp = per_cpu_ptr(&zswap_comp, cpu);
+       zcomp->dstmem = dst;
        return 0;
 }
 
 static int zswap_dstmem_dead(unsigned int cpu)
 {
-       u8 *dst;
+       struct zswap_comp *zcomp;
 
-       dst = per_cpu(zswap_dstmem, cpu);
-       kfree(dst);
-       per_cpu(zswap_dstmem, cpu) = NULL;
+       zcomp = per_cpu_ptr(&zswap_comp, cpu);
+       kfree(zcomp->dstmem);
+       zcomp->dstmem = NULL;
 
        return 0;
 }
@@ -935,10 +946,11 @@ static int zswap_writeback_entry(struct zpool *pool, unsigned long handle)
                dlen = PAGE_SIZE;
                src = (u8 *)zhdr + sizeof(struct zswap_header);
                dst = kmap_atomic(page);
-               tfm = *get_cpu_ptr(entry->pool->tfm);
+               local_lock(&zswap_comp.lock);
+               tfm = *this_cpu_ptr(entry->pool->tfm);
                ret = crypto_comp_decompress(tfm, src, entry->length,
                                             dst, &dlen);
-               put_cpu_ptr(entry->pool->tfm);
+               local_unlock(&zswap_comp.lock);
                kunmap_atomic(dst);
                BUG_ON(ret);
                BUG_ON(dlen != PAGE_SIZE);
@@ -1090,12 +1102,12 @@ static int zswap_frontswap_store(unsigned type, pgoff_t offset,
        }
 
        /* compress */
-       dst = get_cpu_var(zswap_dstmem);
-       tfm = *get_cpu_ptr(entry->pool->tfm);
+       local_lock(&zswap_comp.lock);
+       dst = *this_cpu_ptr(&zswap_comp.dstmem);
+       tfm = *this_cpu_ptr(entry->pool->tfm);
        src = kmap_atomic(page);
        ret = crypto_comp_compress(tfm, src, PAGE_SIZE, dst, &dlen);
        kunmap_atomic(src);
-       put_cpu_ptr(entry->pool->tfm);
        if (ret) {
                ret = -EINVAL;
                goto put_dstmem;
@@ -1119,7 +1131,7 @@ static int zswap_frontswap_store(unsigned type, pgoff_t offset,
        memcpy(buf, &zhdr, hlen);
        memcpy(buf + hlen, dst, dlen);
        zpool_unmap_handle(entry->pool->zpool, handle);
-       put_cpu_var(zswap_dstmem);
+       local_unlock(&zswap_comp.lock);
 
        /* populate entry */
        entry->offset = offset;
@@ -1147,7 +1159,7 @@ insert_entry:
        return 0;
 
 put_dstmem:
-       put_cpu_var(zswap_dstmem);
+       local_unlock(&zswap_comp.lock);
        zswap_pool_put(entry->pool);
 freepage:
        zswap_entry_cache_free(entry);
@@ -1192,9 +1204,10 @@ static int zswap_frontswap_load(unsigned type, pgoff_t offset,
        if (zpool_evictable(entry->pool->zpool))
                src += sizeof(struct zswap_header);
        dst = kmap_atomic(page);
-       tfm = *get_cpu_ptr(entry->pool->tfm);
+       local_lock(&zswap_comp.lock);
+       tfm = *this_cpu_ptr(entry->pool->tfm);
        ret = crypto_comp_decompress(tfm, src, entry->length, dst, &dlen);
-       put_cpu_ptr(entry->pool->tfm);
+       local_unlock(&zswap_comp.lock);
        kunmap_atomic(dst);
        zpool_unmap_handle(entry->pool->zpool, entry->handle);
        BUG_ON(ret);
index d656716..05b0f04 100644 (file)
@@ -282,7 +282,7 @@ config CGROUP_NET_CLASSID
 
 config NET_RX_BUSY_POLL
        bool
-       default y
+       default y if !PREEMPT_RT
 
 config BQL
        bool
index 0bab2ac..bccaf66 100644 (file)
@@ -221,14 +221,14 @@ 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
 }
 
@@ -3050,6 +3050,7 @@ 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)
@@ -3112,6 +3113,7 @@ 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);
 
@@ -3786,7 +3788,11 @@ 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
+       contended = true;
+#else
        contended = qdisc_is_running(q);
+#endif
        if (unlikely(contended))
                spin_lock(&q->busylock);
 
@@ -4585,6 +4591,7 @@ drop:
        rps_unlock(sd);
 
        local_irq_restore(flags);
+       preempt_check_resched_rt();
 
        atomic_long_inc(&skb->dev->rx_dropped);
        kfree_skb(skb);
@@ -4800,7 +4807,7 @@ 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);
@@ -4810,14 +4817,14 @@ 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;
 }
@@ -4856,11 +4863,9 @@ 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();
        trace_netif_rx_ni_exit(err);
 
        return err;
@@ -6336,12 +6341,14 @@ 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. */
                net_rps_send_ipi(remsd);
        } else
 #endif
                local_irq_enable();
+       preempt_check_resched_rt();
 }
 
 static bool sd_has_rps_ipi_waiting(struct softnet_data *sd)
@@ -6419,6 +6426,7 @@ 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);
 
@@ -10969,6 +10977,7 @@ static int dev_cpu_dead(unsigned int oldcpu)
 
        raise_softirq_irqoff(NET_TX_SOFTIRQ);
        local_irq_enable();
+       preempt_check_resched_rt();
 
 #ifdef CONFIG_RPS
        remsd = oldsd->rps_ipi_list;
@@ -10982,7 +10991,7 @@ static int dev_cpu_dead(unsigned int oldcpu)
                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);
        }
@@ -11298,7 +11307,7 @@ static int __init net_dev_init(void)
 
                INIT_WORK(flush, flush_backlog);
 
-               skb_queue_head_init(&sd->input_pkt_queue);
+               skb_queue_head_init_raw(&sd->input_pkt_queue);
                skb_queue_head_init(&sd->process_queue);
 #ifdef CONFIG_XFRM_OFFLOAD
                skb_queue_head_init(&sd->xfrm_backlog);
index 8e582e2..e51f485 100644 (file)
@@ -42,7 +42,7 @@
 struct net_rate_estimator {
        struct gnet_stats_basic_packed  *bstats;
        spinlock_t              *stats_lock;
-       seqcount_t              *running;
+       net_seqlock_t           *running;
        struct gnet_stats_basic_cpu __percpu *cpu_bstats;
        u8                      ewma_log;
        u8                      intvl_log; /* period : (250ms << intvl_log) */
@@ -125,7 +125,7 @@ int gen_new_estimator(struct gnet_stats_basic_packed *bstats,
                      struct gnet_stats_basic_cpu __percpu *cpu_bstats,
                      struct net_rate_estimator __rcu **rate_est,
                      spinlock_t *lock,
-                     seqcount_t *running,
+                     net_seqlock_t *running,
                      struct nlattr *opt)
 {
        struct gnet_estimator *parm = nla_data(opt);
@@ -226,7 +226,7 @@ int gen_replace_estimator(struct gnet_stats_basic_packed *bstats,
                          struct gnet_stats_basic_cpu __percpu *cpu_bstats,
                          struct net_rate_estimator __rcu **rate_est,
                          spinlock_t *lock,
-                         seqcount_t *running, struct nlattr *opt)
+                         net_seqlock_t *running, struct nlattr *opt)
 {
        return gen_new_estimator(bstats, cpu_bstats, rate_est,
                                 lock, running, opt);
index e491b08..ef432ce 100644 (file)
@@ -137,7 +137,7 @@ __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)
@@ -150,15 +150,15 @@ __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);
 
 static 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,
@@ -204,7 +204,7 @@ ___gnet_stats_copy_basic(const seqcount_t *running,
  * 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)
@@ -228,7 +228,7 @@ EXPORT_SYMBOL(gnet_stats_copy_basic);
  * if the room in the socket buffer was not sufficient.
  */
 int
-gnet_stats_copy_basic_hw(const seqcount_t *running,
+gnet_stats_copy_basic_hw(net_seqlock_t *running,
                         struct gnet_dump *d,
                         struct gnet_stats_basic_cpu __percpu *cpu,
                         struct gnet_stats_basic_packed *b)
index 6d9af4e..7a17590 100644 (file)
@@ -3056,12 +3056,11 @@ 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);
 
@@ -3110,12 +3109,11 @@ bool lock_sock_fast(struct sock *sk)
 
        __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, 0, 0, _RET_IP_);
-       local_bh_enable();
        return true;
 }
 EXPORT_SYMBOL(lock_sock_fast);
index e093847..b8369af 100644 (file)
@@ -637,7 +637,9 @@ int __inet_hash(struct sock *sk, struct sock *osk)
        int err = 0;
 
        if (sk->sk_state != TCP_LISTEN) {
+               local_bh_disable();
                inet_ehash_nolisten(sk, osk, NULL);
+               local_bh_enable();
                return 0;
        }
        WARN_ON(!sk_unhashed(sk));
@@ -669,11 +671,8 @@ int inet_hash(struct sock *sk)
 {
        int err = 0;
 
-       if (sk->sk_state != TCP_CLOSE) {
-               local_bh_disable();
+       if (sk->sk_state != TCP_CLOSE)
                err = __inet_hash(sk, NULL);
-               local_bh_enable();
-       }
 
        return err;
 }
@@ -684,17 +683,20 @@ void inet_unhash(struct sock *sk)
        struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo;
        struct inet_listen_hashbucket *ilb = NULL;
        spinlock_t *lock;
+       bool state_listen;
 
        if (sk_unhashed(sk))
                return;
 
        if (sk->sk_state == TCP_LISTEN) {
+               state_listen = true;
                ilb = &hashinfo->listening_hash[inet_sk_listen_hashfn(sk)];
-               lock = &ilb->lock;
+               spin_lock(&ilb->lock);
        } else {
+               state_listen = false;
                lock = inet_ehash_lockp(hashinfo, sk->sk_hash);
+               spin_lock_bh(lock);
        }
-       spin_lock_bh(lock);
        if (sk_unhashed(sk))
                goto unlock;
 
@@ -707,7 +709,10 @@ void inet_unhash(struct sock *sk)
        __sk_nulls_del_node_init_rcu(sk);
        sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
 unlock:
-       spin_unlock_bh(lock);
+       if (state_listen)
+               spin_unlock(&ilb->lock);
+       else
+               spin_unlock_bh(lock);
 }
 EXPORT_SYMBOL_GPL(inet_unhash);
 
index 67c9114..0a2e7f2 100644 (file)
@@ -333,11 +333,8 @@ int inet6_hash(struct sock *sk)
 {
        int err = 0;
 
-       if (sk->sk_state != TCP_CLOSE) {
-               local_bh_disable();
+       if (sk->sk_state != TCP_CLOSE)
                err = __inet_hash(sk, NULL);
-               local_bh_enable();
-       }
 
        return err;
 }
index 7b24582..99390f2 100644 (file)
@@ -1264,7 +1264,7 @@ 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 b5005ab..60013a6 100644 (file)
@@ -578,7 +578,11 @@ 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
+       .running        =       __SEQLOCK_UNLOCKED(noop_qdisc.running),
+#else
        .running        =       SEQCNT_ZERO(noop_qdisc.running),
+#endif
        .busylock       =       __SPIN_LOCK_UNLOCKED(noop_qdisc.busylock),
        .gso_skb = {
                .next = (struct sk_buff *)&noop_qdisc.gso_skb,
@@ -889,9 +893,15 @@ struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
        lockdep_set_class(&sch->seqlock,
                          dev->qdisc_tx_busylock ?: &qdisc_tx_busylock);
 
+#ifdef CONFIG_PREEMPT_RT
+       seqlock_init(&sch->running);
+       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->flags = ops->static_flags;
index 06e5034..16bd127 100644 (file)
@@ -422,7 +422,7 @@ void svc_xprt_do_enqueue(struct svc_xprt *xprt)
        if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags))
                return;
 
-       cpu = get_cpu();
+       cpu = get_cpu_light();
        pool = svc_pool_for_cpu(xprt->xpt_server, cpu);
 
        atomic_long_inc(&pool->sp_stats.packets);
@@ -446,7 +446,7 @@ void svc_xprt_do_enqueue(struct svc_xprt *xprt)
        rqstp = NULL;
 out_unlock:
        rcu_read_unlock();
-       put_cpu();
+       put_cpu_light();
        trace_svc_xprt_do_enqueue(xprt, rqstp);
 }
 EXPORT_SYMBOL_GPL(svc_xprt_do_enqueue);
index 65e2805..3a6f683 100644 (file)
@@ -2694,7 +2694,8 @@ int __net_init xfrm_state_init(struct net *net)
        net->xfrm.state_num = 0;
        INIT_WORK(&net->xfrm.state_hash_work, xfrm_hash_resize);
        spin_lock_init(&net->xfrm.xfrm_state_lock);
-       seqcount_init(&net->xfrm.xfrm_state_hash_generation);
+       seqcount_spinlock_init(&net->xfrm.xfrm_state_hash_generation,
+                              &net->xfrm.xfrm_state_lock);
        return 0;
 
 out_byspi: