platform/kernel/linux-exynos.git
7 years agoLOCAL / dwc3: add otg handling code
Robert Baldyga [Mon, 23 Feb 2015 11:01:54 +0000 (12:01 +0100)]
LOCAL / dwc3: add otg handling code

This code is based on DWC3 driver from https://github.com/hardkernel/linux.

Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>
7 years agoLOCAL / dwc3: core: cleanup suspend/resume code
Robert Baldyga [Mon, 9 Mar 2015 08:41:24 +0000 (09:41 +0100)]
LOCAL / dwc3: core: cleanup suspend/resume code

Remove unused cases from switch-case statement and place
dwc3_event_buffers_cleanup() function outside switch-case
as it's called in each case anyway.

Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>
7 years agoLOCAL / usb: gadget: change gadget connect order
Jaewon Kim [Thu, 26 Feb 2015 07:38:13 +0000 (16:38 +0900)]
LOCAL / usb: gadget: change gadget connect order

This patch changes usb_gadget_connect() order before add config.

Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
7 years agoLOCAL / arm64: dts: fix usb handle for Exynos5433 tm2 borad.
Jaewon Kim [Tue, 31 Mar 2015 05:25:08 +0000 (14:25 +0900)]
LOCAL / arm64: dts: fix usb handle for Exynos5433 tm2 borad.

This patch fixes usb handle name for Exynos5433 tm2 board.

Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
7 years agoLOCAL / arm64: dts: fix usb3.0 host dt handle
Jaewon Kim [Tue, 31 Mar 2015 05:22:03 +0000 (14:22 +0900)]
LOCAL / arm64: dts: fix usb3.0 host dt handle

This patch fixes USB3.0 host dt handle to usbhost30.

Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
7 years agoLOCAL / arm64: dts: fix usbdrd handle name
Jaewon Kim [Tue, 31 Mar 2015 05:18:21 +0000 (14:18 +0900)]
LOCAL / arm64: dts: fix usbdrd handle name

This patch fixes usbdrd handle name

Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
7 years agoLOCAL / arm64: dts: exynos: Remove high-frequency of big core to remove kernel lockup
Chanwoo Choi [Tue, 31 Mar 2015 04:34:09 +0000 (13:34 +0900)]
LOCAL / arm64: dts: exynos: Remove high-frequency of big core to remove kernel lockup

This patch removes the high-frequency of big core from frequency table
to remove kernel lockup issue. This is work-around method to resolve lockup.
Firstly, after making the stable kernel, I'll debug this isuse.

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
7 years agolocal / arm64: configs: update defconfig for syscon-reboot
Joonyoung Shim [Tue, 31 Mar 2015 01:50:18 +0000 (10:50 +0900)]
local / arm64: configs: update defconfig for syscon-reboot

Exynos5433 SoC can support to reboot using syscon-reboot driver.

Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
7 years agolocal / arm64: dts: add reboot node for exynos5433
Joonyoung Shim [Tue, 31 Mar 2015 01:47:51 +0000 (10:47 +0900)]
local / arm64: dts: add reboot node for exynos5433

This reboot node uses syscon-reboot driver.

Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
7 years agolocal / arm64: configs: update defconfig for mali
Joonyoung Shim [Fri, 23 Jan 2015 09:08:10 +0000 (18:08 +0900)]
local / arm64: configs: update defconfig for mali

Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
7 years agogpu: arm: midgard: add initial exynos5433 platform files
Joonyoung Shim [Mon, 19 Jan 2015 08:54:35 +0000 (17:54 +0900)]
gpu: arm: midgard: add initial exynos5433 platform files

We should check more clock and regulator for DVFS.

Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
7 years agogpu: arm: midgard: remove set_dma_ops
Joonyoung Shim [Tue, 10 Mar 2015 01:07:08 +0000 (10:07 +0900)]
gpu: arm: midgard: remove set_dma_ops

Don't use set_dma_ops since commit 9d3bfbb4df58 ("arm64: Combine
coherent and non-coherent swiotlb dma_ops")

Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
7 years agogpu: arm: midgard: Drop CONFIG_PM_RUNTIME
Joonyoung Shim [Wed, 21 Jan 2015 08:13:51 +0000 (17:13 +0900)]
gpu: arm: midgard: Drop CONFIG_PM_RUNTIME

After commit 464ed18ebdb6 ("PM: Eliminate CONFIG_PM_RUNTIME") PM_RUNTIME
is eliminated.

Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
7 years agogpu: arm: midgard: add initial exynos5422 platform files
Joonyoung Shim [Mon, 19 Jan 2015 08:54:35 +0000 (17:54 +0900)]
gpu: arm: midgard: add initial exynos5422 platform files

We should check more clock and regulator for DVFS.

Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
7 years agogpu: arm: midgard: support kernel error defines for platform.
Joonyoung Shim [Tue, 20 Jan 2015 09:07:38 +0000 (18:07 +0900)]
gpu: arm: midgard: support kernel error defines for platform.

Don't use mali error defines, it'a ugly.

Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
7 years agogpu: arm: add mali midgard r5p0-06rel0 driver
Joonyoung Shim [Tue, 20 Jan 2015 02:18:00 +0000 (11:18 +0900)]
gpu: arm: add mali midgard r5p0-06rel0 driver

This comes from below link. Remove sconscript and modify file permission
to 644.

http://malideveloper.arm.com/develop-for-mali/drivers/open-source-mali-t6xx-gpu-kernel-device-drivers/

Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
7 years agosched: hmp: fix spinlock recursion in active migration
Kevin Hilman [Wed, 12 Aug 2015 10:19:09 +0000 (19:19 +0900)]
sched: hmp: fix spinlock recursion in active migration

[original commit message]
Commit cd5c2cc93d3d (hmp: Remove potential for task_struct access
race) introduced a put_task_struct() to prevent races, but in
doing so introduced potential spinlock recursion.  (This change was further
onsolidated in commit 0baa5811bacf -- sched: hmp: unify active migration code.)

Unfortunately, the put_task_struct() is done while the runqueue
spinlock is held, but put_task_struct() can also cause a reschedule
causing the runqueue lock to be acquired recursively.

To fix, move the put_task_struct() outside the runqueue spinlock.

[additional commit message by Chanwoo Choi]
We did not apply hmp patch[1] because patch[1] clean the code by sharing the
same code. When I applied hmp patch[1], scheduling problem issue occured.
[1] commit 0baa5811bacf -- sched: hmp: unify active migration code.)
So, this patch move the put_task_struct() just outside the runqueue spinlock.

Reported-by: Victor Lixin <victor.lixin@hisilicon.com>
Cc: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org>
Cc: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Kevin Hilman <khilman@linaro.org>
Reviewed-by: Jon Medhurst <tixy@linaro.org>
Reviewed-by: Alex Shi <alex.shi@linaro.org>
Reviewed-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[cw00.choi: Fix the merge conflict]
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
7 years agohmp: Restrict ILB events if no CPU has > 1 task
Chris Redpath [Thu, 12 Mar 2015 11:32:13 +0000 (20:32 +0900)]
hmp: Restrict ILB events if no CPU has > 1 task

Frequently in HMP, the big CPUs are only active with one task per
CPU and there may be idle CPUs in the big cluster. This patch avoids
triggering an idle balance in situations where none of the active
CPUs in the current HMP domain have > 1 tasks running.

When packing is enabled, only enforce this behaviour when we are
not in the smallest domain - there we idle balance whenever a CPU
is over the up_threshold regardless of tasks in case one needs to
be moved.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
7 years agoHMP: Do not fork-boost tasks coming from PIDs <= 2
Chris Redpath [Thu, 12 Mar 2015 11:19:34 +0000 (20:19 +0900)]
HMP: Do not fork-boost tasks coming from PIDs <= 2

System services are generally started by init, whilst kernel threads
are started by kthreadd. We do not want to give those tasks a head
start, as this costs power for very little benefit. We do however
wish to do that for tasks which the user launches.

Further, some tasks allocate per-cpu timers directly after launch
which can lead to those tasks being always scheduled on a big CPU
when there is no computational need to do so. Not promoting services
to big CPUs on launch will prevent that unless a service allocates
their per-cpu resources after a period of intense computation, which
is not a common pattern.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
7 years agoHMP: use per cpu cpuidle driver to fix deadlock in hmp_idle_pull
Alex Shi [Thu, 12 Mar 2015 11:13:22 +0000 (20:13 +0900)]
HMP: use per cpu cpuidle driver to fix deadlock in hmp_idle_pull

Using per cpu cpuidle driver to fix deadlock in hmp_idle_pull.
Otherwise a deadlock happened when do bl_idle_init.

[  113.878664] other info that might help us debug this:
[  113.878667]  Possible unsafe locking scenario:
[  113.878667]
[  113.878670]        CPU0
[  113.878673]        ----
[  113.878681]   lock(cpuidle_driver_lock);
[  113.878684]   <Interrupt>
[  113.878691]     lock(cpuidle_driver_lock);
[  113.878693]
[  113.878693]  *** DEADLOCK ***
[  113.878693]
[  113.878697] 1 lock held by ksoftirqd/4/28:
[  113.878719]  #0:  (hmp_force_migration){+.....}, at: [<c0054da5>]
hmp_idle_pull+0x49/0x508

This patch is just a quick/cheap workaround for cpuidle_driver_lock
deadlock. It works for TC2 and any other platform where the idle
driver cannot be changed at runtime.

Signed-off-by: Alex Shi <alex.shi@linaro.org>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
7 years agosched: hmp: fix out-of-range CPU possible
Chris Redpath [Thu, 12 Mar 2015 11:10:45 +0000 (20:10 +0900)]
sched: hmp: fix out-of-range CPU possible

If someone hotplugs all the little CPUs while another CPU is handling
a wakeup, we can potentially return new_cpu == NR_CPUS from
hmp_select_slower_cpu (which is called internally by
hmp_best_little_cpu as well). We will use this to deref the
per_cpu rq array in hmp_next_down_delay which can go boom.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
7 years agohmp: dont attempt to pull tasks if affinity doesn't allow it
Chris Redpath [Thu, 12 Mar 2015 11:04:08 +0000 (20:04 +0900)]
hmp: dont attempt to pull tasks if affinity doesn't allow it

When looking for a task to be idle-pulled, don't consider tasks
where the affinity does not allow that task to be placed on the
target CPU. Also ensure that tasks with restricted affinity
do not block selecting other unrestricted busy tasks.

Use the knowledge of target CPU more effectively in idle pull
by passing to hmp_get_heaviest_task when we know it, otherwise
only checking for general affinity matches with any of the CPUs
in the bigger HMP domain.

We still need to explicitly check affinity is allowed in idle pull
since if we find no match in hmp_get_heaviest_task we will return
the current one, which may not be affine to the new CPU despite
having high enough load. In this case, there is nothing to move.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agohmp: Use idle pull to perform forced up-migrations
Chris Redpath [Thu, 12 Mar 2015 10:57:56 +0000 (19:57 +0900)]
hmp: Use idle pull to perform forced up-migrations

When a normal forced up-migration takes place we stop the task to
be migrated while the target CPU becomes available. This delay can
range from 80us to 1500us on TC2 if the target CPU is in a deep idle
state.

Instead, interrupt the target CPU and ask it to pull a task.
This lets the current eligible task continue executing on the
original CPU while the target CPU wakes. Use a pinned timer to
prevent the pulling CPU going back into power-down with pending
up-migrations.

If we trigger for a nohz kick, it doesn't matter about triggering
for an idle pull since the idle_pull flag will be set when we
execute the softirq and we'll still do the idle pull.

If the target CPU is busy, we will not pull any tasks.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
7 years agosched: hmp: Change small task packing defaults for all platforms
Chris Redpath [Thu, 12 Mar 2015 10:43:19 +0000 (19:43 +0900)]
sched: hmp: Change small task packing defaults for all platforms

All platforms other than TC2 default to enabling packing. Since TC2
shows no performance or energy degradation with this feature enabled
make it default enabled the same as everyone else.
Likewise, vendors have been including TC2 support in multi-machine
kernel builds so they expect the default thresholds to remain the
same when the TC2 #ifdef is removed.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
7 years agoLOCAL / sched: Fix build break by using alternative function
Chanwoo Choi [Thu, 12 Mar 2015 05:45:47 +0000 (14:45 +0900)]
LOCAL / sched: Fix build break by using alternative function

This patch fixes the build break because Linux 4.0 didn't include the
cpumask_scnprintf() function. So, this patch use the alternative function
(cpumap_print_to_pagebuf()).

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
[k.kozlowski: rebased on 4.1]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agohmp: sched: Clean up hmp_up_threshold checks into a utility fn
Chris Redpath [Wed, 4 Feb 2015 05:55:19 +0000 (14:55 +0900)]
hmp: sched: Clean up hmp_up_threshold checks into a utility fn

In anticipation of modifying the up_threshold handling, make all
instances use the same utility fn to check if a task is eligible
for up-migration. This also removes the previous difference in
threshold comparison where up-migration used '!<threshold' and
idle pull used '>threshold' to decide up-migration eligibility.
Make them both use '!<threshold' instead for consistency, although
this is unlikely to change any results.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
7 years agoHMP: Fix rt task allowed cpu mask restriction code on 1x1 system
Dietmar Eggemann [Wed, 4 Feb 2015 05:50:24 +0000 (14:50 +0900)]
HMP: Fix rt task allowed cpu mask restriction code on 1x1 system

There is an error scenario where on a 1x1 HMP system (weight of the
hmp_slow_cpu_mask is 1) the short-cut of restricting the
allowed cpu mask
of an rt tasks leads to triggering a kernel bug in the rt sched class
set_cpus_allowed function set_cpus_allowed_rt().

In case the task is on the run-queue and the weight of the required cpu mask
is 1 and this is different to the p->nr_cpus_allowed value, this back-end
function interprets this in such a way that a task changed from being
migratable to not migratable anymore and decrements the rt_nr_migratory
counter.  There is a BUG_ON(!rq->rt.rt_nr_migratory) check in this code
path which triggers in this situation.

To circumvent this issue, set the number of allowed cpus for a task p to
the weight of the hmp_slow_cpu_mask before calling do_set_cpus_allowed()
in __setscheduler(). It will be set to this value in
do_set_cpus_allowed()
after the call to the sched class related backend function any way.  By
doing this, set_cpus_allowed_rt() returns without trying to update the
rt_nr_migratory counter.

This patch has been tested with a test device driver requiring a
threaded
irq handler on a TC2 system with a reduced cpu mask (1 Cortex A15, 1
Cortex A7).

Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
7 years agoHMP: Restrict irq_default_affinity to hmp_slow_cpu_mask
Dietmar Eggemann [Wed, 4 Feb 2015 05:48:35 +0000 (14:48 +0900)]
HMP: Restrict irq_default_affinity to hmp_slow_cpu_mask

This patch limits the default affinity mask for all irqs to the cluster of
the little cpus.

This patch has the positive side effect that an irq thread which has its
IRQTF_RUNTHREAD set inside irq_thread() -> irq_wait_for_interrupt() will
not overwrite its struct task_struct->cpus_allowed with a full cpu mask of
desc->irq_data.affinity in irq_thread_check_affinity() essentially reverting
patch "HMP: experimental: Force all rt tasks to start on little domain."
for this irq thread.

Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
7 years agosched: hmp: Fix potential task_struct memory leak
Chris Redpath [Wed, 4 Feb 2015 05:44:53 +0000 (14:44 +0900)]
sched: hmp: Fix potential task_struct memory leak

We use get_task_struct to increment the ref count on a task_struct
so that even if the task dies with a pending migration we are still
able to read the memory without causing a fault.

In the case of non-running tasks, we forgot to decrement the ref
count when we are done with the task.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
7 years agosched: hmp: Change TC2 packing config to disabled default if present
Chris Redpath [Wed, 4 Feb 2015 05:42:51 +0000 (14:42 +0900)]
sched: hmp: Change TC2 packing config to disabled default if present

Since TC2 power curves don't really have a utilisation hotspot where
packing makes sense, if it is present for a TC2 system at least make
it default to disabled.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: hmp: Make idle balance behaviour normal when packing disabled
Chris Redpath [Wed, 4 Feb 2015 05:40:41 +0000 (14:40 +0900)]
sched: hmp: Make idle balance behaviour normal when packing disabled

The presence of packing permanently changed the idle balance
behaviour. Do not restrict idle balance on the smallest CPUs when
packing is present but disabled.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: update runqueue clock before migrations away
Chris Redpath [Wed, 4 Feb 2015 05:25:57 +0000 (14:25 +0900)]
sched: update runqueue clock before migrations away

If we migrate a sleeping task away from a CPU which has the
tick stopped, then both the clock_task and decay_counter will
be out of date for that CPU and we will not decay load correctly
regardless of how often we update the blocked load.

This is only an issue for tasks which are not on a runqueue
(because otherwise that CPU would be awake) and simultaneously
the CPU the task previously ran on has had the tick stopped.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: reset blocked load decay_count during synchronization
Chris Redpath [Mon, 23 Feb 2015 06:24:16 +0000 (15:24 +0900)]
sched: reset blocked load decay_count during synchronization

If an entity happens to sleep for less than one tick duration
the tracked load associated with that entity can be decayed by an
unexpectedly large amount if it is later migrated to a different
CPU. This can interfere with correct scheduling when entity load
is used for decision making.

The reason for this is that when an entity is dequeued and enqueued
quickly, such that se.avg.decay_count and cfs_rq.decay_counter
do not differ when that entity is enqueued again,
__synchronize_entity_decay skips the calculation step and also skips
clearing the decay_count. At a later time that entity may be
migrated and its load will be decayed incorrectly.

All users of this function expect decay_count to be zero'ed after
use.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agogenirq: Add default affinity mask command line option
Thomas Gleixner [Wed, 4 Feb 2015 05:12:25 +0000 (14:12 +0900)]
genirq: Add default affinity mask command line option

If we isolate CPUs, then we don't want random device interrupts on
them. Even w/o the user space irq balancer enabled we can end up with
irqs on non boot cpus.

Allow to restrict the default irq affinity mask.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: hmp: Fix build breakage when not using CONFIG_SCHED_HMP
Chris Redpath [Wed, 4 Feb 2015 05:06:14 +0000 (14:06 +0900)]
sched: hmp: Fix build breakage when not using CONFIG_SCHED_HMP

hmp_variable_scale_convert was used without guards in
__update_entity_runnable_avg. Guard it.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoDocumentation: HMP: Small Task Packing explanation
Chris Redpath [Wed, 20 Nov 2013 14:14:44 +0000 (14:14 +0000)]
Documentation: HMP: Small Task Packing explanation

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: hmp: add read-only hmp domain sysfs file
Chris Redpath [Wed, 4 Feb 2015 02:58:09 +0000 (11:58 +0900)]
sched: hmp: add read-only hmp domain sysfs file

In order to allow userspace to restrict known low-load tasks to
little CPUs, we must export this knowledge from the kernel or
expect userspace to make their own attempts at figuring it out.

Since we now have a userspace requirement for an HMP implementation
to always have at least some sysfs files, change the integration
so that it only depends upon CONFIG_SCHED_HMP rather than
CONFIG_HMP_VARIABLE_SCALE. Fix Kconfig text to match.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoHMP: Avoid using the cpu stopper to stop runnable tasks
Mathieu Poirier [Wed, 4 Feb 2015 02:39:05 +0000 (11:39 +0900)]
HMP: Avoid using the cpu stopper to stop runnable tasks

When migrating a runnable task, we use the CPU stopper on
the source CPU to ensure that the task to be moved is not
currently running. Before this patch, all forced migrations
(up, offload, idle pull) use the stopper for every migration.

Using the CPU stopper is mandatory only when a task is currently
running on a CPU.  Otherwise tasks can be moved by locking the
source and destination run queues.

This patch checks to see if the task to be moved are currently
running.  If not the task is moved directly without using the
stopper thread.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosmp: Don't use typedef to work around compiler issue with tracepoints
Mark Brown [Wed, 4 Feb 2015 02:23:34 +0000 (11:23 +0900)]
smp: Don't use typedef to work around compiler issue with tracepoints

Having the typedef in place for the tracepoints causes compiler crashes
in some situations.  Just using void * directly avoids triggering the
issue and should have no effect on the trace.

Signed-off-by: Mark Brown <broonie@linaro.org>
Acked-by: Liviu Dudau <Liviu.Dudau@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoHMP: Implement task packing for small tasks in HMP systems
Chris Redpath [Tue, 3 Feb 2015 12:45:54 +0000 (21:45 +0900)]
HMP: Implement task packing for small tasks in HMP systems

If we wake up a task on a little CPU, fill CPUs rather than
spread. Adds 2 new files to sys/kernel/hmp to control packing
behaviour.

packing_enable: task packing enabled (1) or disabled (0)
packing_limit: Runqueues will be filled up to this load ratio.

This functionality is disabled by default on TC2 as it lacks per-cpu
power gating so packing small tasks there doesn't make sense.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agohmp: Remove potential for task_struct access race
Chris Redpath [Tue, 3 Feb 2015 12:19:41 +0000 (21:19 +0900)]
hmp: Remove potential for task_struct access race

Accessing the task_struct can be racy in certain conditions, so
we need to only acquire the data when needed.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: HMP: fix potential logical errors
Chris Redpath [Tue, 3 Feb 2015 08:34:03 +0000 (17:34 +0900)]
sched: HMP: fix potential logical errors

The previous API for hmp_up_migration reset the destination
CPU every time, regardless of if a migration was desired. The code
using it assumed that the value would not be changed unless
a migration was required. In one rare circumstance, this could
have lead to a task migrating to a little CPU at the wrong time.

Fixing that lead to a slight logical tweak to make the surrounding
APIs operate a bit more obviously.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Robin Randhawa <robin.randhawa@arm.com>
Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosmp: smp_cross_call function pointer tracing
Chris Redpath [Tue, 3 Feb 2015 08:26:54 +0000 (17:26 +0900)]
smp: smp_cross_call function pointer tracing

generic tracing for smp_cross_call function calls

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: HMP: Additional trace points for debugging HMP behaviour
Chris Redpath [Tue, 3 Feb 2015 07:56:54 +0000 (16:56 +0900)]
sched: HMP: Additional trace points for debugging HMP behaviour

1. Replace magic numbers in code for migration trace.
Trace points still emit a number as force=<n> field:
force=0 : wakeup migration
force=1 : forced migration
force=2 : offload migration
force=3 : idle pull migration

2. Add trace to expose offload decision-making.
Also adds tracing rq->nr_running so that you can
look back to see what state the RQ was in at the
time.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: HMP: Change default HMP thresholds
Chris Redpath [Tue, 3 Feb 2015 07:52:16 +0000 (16:52 +0900)]
sched: HMP: Change default HMP thresholds

When the up-threshold is at 512 on TC2, behaviour looks OK since
the graphic-related tasks are very heavy due to lack of a GPU.
Increasing the up-threshold does not reduce power consumption.

When a GPU is present, graphic tasks are much less CPU-heavy and
so additional power may be saved by having a higher threshold.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoHMP: Update migration timer when we fork-migrate
Chris Redpath [Tue, 3 Feb 2015 07:50:59 +0000 (16:50 +0900)]
HMP: Update migration timer when we fork-migrate

Prevents fork-migration adversely interacting with normal
migration (i.e. runqueues containing forked tasks being
selected as migration targets when there is a better
choice available)

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoHMP: Access runqueue task clocks directly.
Chris Redpath [Tue, 3 Feb 2015 07:46:56 +0000 (16:46 +0900)]
HMP: Access runqueue task clocks directly.

Avoids accesses through cfs_rq going bad when the cpu_rq doesn't
have a cfs member.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoHMP: Implement idle pull for HMP
Chris Redpath [Tue, 3 Feb 2015 07:40:16 +0000 (16:40 +0900)]
HMP: Implement idle pull for HMP

When an A15 goes idle, we should up-migrate anything which is
above the threshold and running on an A7.

Reuses the HMP force-migration spinlock, but adds its own new
cpu stopper client.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: HMP change nr_running offload metric
Chris Redpath [Tue, 3 Feb 2015 07:33:30 +0000 (16:33 +0900)]
sched: HMP change nr_running offload metric

rq->nr_running was better than cfs.nr_running, since it includes
all tasks actually on the CPU. However, it includes RT tasks which
we would rather ignore at this point.

Switching to cfs.h_nr_running includes all the CFS tasks but no
RT tasks.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoHMP: Explicitly implement all-load-is-max-load policy for HMP targets
Chris Redpath [Tue, 3 Feb 2015 07:30:36 +0000 (16:30 +0900)]
HMP: Explicitly implement all-load-is-max-load policy for HMP targets

Experimentally, one of the best policies for HMP migration CPU
selection is to completely ignore part-loaded CPUs and only look
for idle ones. If there are no idle ones, we will choose the one
which was least-recently-disturbed.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoHMP: Modify the runqueue stats to add a new child stat
Chris Redpath [Tue, 3 Feb 2015 07:23:22 +0000 (16:23 +0900)]
HMP: Modify the runqueue stats to add a new child stat

The original intent here was to track unweighted runqueue load
with less resolution so we could use the least-recently-disturbed
runqueue to choose between 'closely related' load levels.

However, after experimenting with the resolution it turns out
that the following algorithm is highly beneficial for mobile
workloads.

In hmp_domain_min_load:

  * If any CPU is zero, the overall load is zero
  * If no CPUs are idle, the domain is 'fully loaded'

Additionally, the time since last migration count is used to
discriminate between idle CPUs.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: track per-rq 'last migration time'
Chris Redpath [Tue, 3 Feb 2015 07:08:42 +0000 (16:08 +0900)]
sched: track per-rq 'last migration time'

Track when migrations were performed to runqueues.

Use this to decide between runqueues as migration targets when run
queues in an hmp domain have equal load.

Intention is to spread migration load amongst CPUs more fairly.

When all CPUs in an hmp domain are fully loaded, the existing code
always selects the last CPU as a migration target - this is unfair
and little better than doing no selection.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: HMP fix traversing the rb-tree from the curr pointer
Morten Rasmussen [Tue, 3 Feb 2015 07:02:08 +0000 (16:02 +0900)]
sched: HMP fix traversing the rb-tree from the curr pointer

The hmp_get_{lightest,heaviest}_task() need to use
__pick_first_entity() to get a pointer to a sched_entity on the rq.
The current is not kept on the rq while running, so its rb-tree node
pointers are no longer valid.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoHMP: select 'best' task for migration rather than 'current'
Chris Redpath [Tue, 3 Feb 2015 06:46:36 +0000 (15:46 +0900)]
HMP: select 'best' task for migration rather than 'current'

When we are looking for a task to migrate up, select the heaviest
one in the first 5 runnable on the runqueue.

Likewise, when looking for a task to offload, select the lightest
one in the first 5 runnable on the runqueue.

Ensure task selected is runnable in the target domain.

This change is necessary in order to implement idle pull in a
sensible manner, but here is used in up-migration and offload to
select the correct target task.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoHMP: Check the system has little cpus before forcing rt tasks onto them
Jon Medhurst [Tue, 3 Feb 2015 06:40:18 +0000 (15:40 +0900)]
HMP: Check the system has little cpus before forcing rt tasks onto them

It is sometimes desirable to run a kernel with HMP scheduling enabled
on a system which is not big.LITTLE, e.g. when building a multi-platform
kernel, or when testing a big.LITTLE system with one cluster disabled.

We should therefore allow for the situation where is no little domain.

Signed-off-by: Jon Medhurst <tixy@linaro.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoHMP: experimental: Force all rt tasks to start on little domain.
Dietmar Eggemann [Tue, 3 Feb 2015 06:38:08 +0000 (15:38 +0900)]
HMP: experimental: Force all rt tasks to start on little domain.

This patch restricts the allowed cpu mask for rt tasks initially started
with a full cpu mask to the little domain.

An rt task is specified as real time in __setscheduler() which is finally
called for all rt tasks (kernel and user land). In this function we
restrict the allowed cpu mask to the little domain.

This also prevents that a rt tasks can later be pushed to the big domain
because the function find_lowest_rq() will only recognize the allowed cpu
mask of a task to find the new cpu the task runs on.

Current kludges of the patch:

* Since we do not have an API to get the cpu mask of the A7 cluster,
hmp_slow_cpu_mask is made global in arm/kernel/topology.c for now.

* The watchdog_enable() function calls sched_setscheduler() before
kthread_bind() for the cpu specific watchdog kernel threads. The order of
these two calls has to be changed to make this patch work.

Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoLOCAL / sched: Fix build break
Chanwoo Choi [Tue, 3 Feb 2015 06:32:43 +0000 (15:32 +0900)]
LOCAL / sched: Fix build break

kernel/sched/fair.c: In function â€˜find_new_ilb’:
kernel/sched/fair.c:7973:42: error: â€˜call_cpu’ undeclared (first use in this function)
    &((struct hmp_domain *)hmp_cpu_domain(call_cpu))->cpus);

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
7 years agosched: Restrict nohz balance kicks to stay in the HMP domain
Chris Redpath [Tue, 3 Feb 2015 05:03:11 +0000 (14:03 +0900)]
sched: Restrict nohz balance kicks to stay in the HMP domain

There is little point in doing a nohz balance kick on a CPU from a
different HMP domain, since the unset SD_LOAD_BALANCE flag on the CPU
domain level prevents tasks from being balanced across clusters
except through the per-task load driven hmp_migrate/hmp_offload paths.

Further, the nohz balance kick is actively harmful to power usage if
all the tasks fit into the little domain since it causes the big
domain to wake up and do a lot of calculation to determine that
there is nothing to do.

A more generic solution is to walk the sched domain tree and determine
the intersection of potential idle balance cpus with visibility of
tasks on the current CPU, however HMP domains are more easily
accessible.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoHMP: Force new non-kernel tasks onto big CPUs until load stabilises
Chris Redpath [Mon, 23 Feb 2015 06:19:03 +0000 (15:19 +0900)]
HMP: Force new non-kernel tasks onto big CPUs until load stabilises

Initialise the load stats for new tasks so that they do not
see the instability in early task life which makes it so hard to
decide which CPU is appropriate.

Also, change the fork balance algorithm so that the least loaded of
the CPUs in the big cluster is chosen regardless of the bigness of
the parent task.

This is intended to help performance for applications which use
many short-lived tasks. Although best practise is usually to use
a thread pool, apps which do not do this should not be subject to
the randomness of the early stats.

We should ignore real-time threads for forking on big CPUs, but
it is not possible to figure out if a new thread is real-time or
not at the fork stage. Instead, we prevent kernel threads from
getting the initial boost - when they later become real-time they
will only be on big if their compute requirements demand it.

Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoHMP: Avoid multiple calls to hmp_domain_min_load in fast path
Chris Redpath [Fri, 30 Jan 2015 08:10:42 +0000 (17:10 +0900)]
HMP: Avoid multiple calls to hmp_domain_min_load in fast path

When evaluating a migration we make two calls to hmp_domain_min_load.
This is unnecessary if we pass on the target CPU information from the
hmp_up_migration path.

In hmp_down_migration, we don't consider the load of the target CPUS.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoHMP: Select least-loaded CPU when performing HMP Migrations
Chris Redpath [Fri, 30 Jan 2015 08:04:09 +0000 (17:04 +0900)]
HMP: Select least-loaded CPU when performing HMP Migrations

The reference patch set always selects the first CPU in an HMP
domain as a migration target. In busy situations, this means that
the migrated thread cannot make immediate use of an idle CPU but
must share a busy one until the load balancer runs across the big
domain.

This patch uses the hmp_domain_min_load function introduced in
global balancing to figure out which of the CPUs is the least busy
and selects that as a migration target - in both directions.

This essentially implements a task-spread strategy and is intended
to maximise performance of migrated threads but is likely
to use more power than the packing strategy previously employed.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoHMP: Use unweighted load for hmp migration decisions
Chris Redpath [Fri, 30 Jan 2015 07:59:46 +0000 (16:59 +0900)]
HMP: Use unweighted load for hmp migration decisions

Normal task and runqueue loading is scaled according to priority
to end up with a weighted load, known as the contribution.

We want the CPU time to be allotted according to priority, but
we also want to make big/little decisions based upon raw load.

It is common, for example, for Android apps following the dev
guide to end up with all their long-running or async action
threads as low priority unless they override the AsyncThread
constructor. All these threads are such low priority that they
become invisible to the hmp_offload routine.

Using unweighted load here allows us to maximise CPU usage in busy
situations.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoRevert "sched: Enable HMP priority filter by default"
Chris Redpath [Fri, 30 Jan 2015 07:44:17 +0000 (16:44 +0900)]
Revert "sched: Enable HMP priority filter by default"

This reverts commit 6ede44cadf39e35cd2f4fc0ebda8d85f6eca8947.

Having the priority filter enabled prevents proper operation
on Android systems where a wider range of priorities are used
by userspace to partition types of tasks. Those tasks should still
be able to benefit from the use of big CPUs when required.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
7 years agosched: cfs.nr_running does not contain the intended metric
Chris Redpath [Fri, 30 Jan 2015 07:29:35 +0000 (16:29 +0900)]
sched: cfs.nr_running does not contain the intended metric

rq->nr_running is the actual number of runnable tasks we wish to use
to determine if a task is alone on a CPU.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: Basic global balancing support for HMP
Morten Rasmussen [Fri, 30 Jan 2015 07:27:45 +0000 (16:27 +0900)]
sched: Basic global balancing support for HMP

This patch introduces an extra-check at task up-migration to
prevent overloading the cpus in the faster hmp_domain while the
slower hmp_domain is not fully utilized. The patch also introduces
a periodic balance check that can down-migrate tasks if the faster
domain is oversubscribed and the slower is under-utilized.

Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoARM: Fix build breakage when big.LITTLE.conf is not used.
Chris Redpath [Fri, 30 Jan 2015 07:22:26 +0000 (16:22 +0900)]
ARM: Fix build breakage when big.LITTLE.conf is not used.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoARM: Experimental Frequency-Invariant Load Scaling Patch
Olivier Cozette [Fri, 30 Jan 2015 06:47:57 +0000 (15:47 +0900)]
ARM: Experimental Frequency-Invariant Load Scaling Patch

Evaluation Patch to investigate using load as a representation of the
amount of POTENTIAL cpu compute capacity used rather than a representation
of the CURRENT cpu compute capacity.

If CPUFreq is enabled, scales load in accordance with frequency.

Powersave/performance CPUFreq governors are detected and scaling is
disabled while these governors are in use. This is because when a
single-frequency governor is in use, potential CPU capacity is static.

So long as the governors and CPUFreq subsystem correctly report the
frequencies available, the scaling should self tune.

Adds an additional file to sysfs to allow this feature to be disabled
for experimentation.

/sys/kernel/hmp/frequency_invariant_load_scale

write 0 to disable, 1 to enable.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoARM: Change load tracking scale using sysfs
Olivier Cozette [Fri, 30 Jan 2015 06:08:58 +0000 (15:08 +0900)]
ARM: Change load tracking scale using sysfs

These functions allow to change the load average period used
in the task load average computation through
/sys/kernel/hmp/load_avg_period_ms. This period is the time
in ms to go from 0 to 0.5 load average while running or the
time from 1 to 0.5 while sleeping.

The default one used is 32 and gives the same load_avg_ratio
computation than without this patch. These functions also allow
to change the up and down threshold of HMP using
/sys/kernel/hmp/{up,down}_threshold. Both must be between 0 and
1024. The thresholds are divided by 1024 before being compared
to the load_avg_ratio.

If /sys/kernel/hmp/load_avg_period_ms is 128 and
/sys/kernel/hmp/up_threshold is 512, a task will be migrated
to a bigger cluster after running for 128ms. Because after
load_avg_period_ms the load average is 0.5 and real up_threshold
us 512 / 1024 = 0.5.

Signed-off-by: Olivier Cozette <olivier.cozette@arm.com>
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoched: Ignore offline CPUs in HMP migration & load stats
Chris Redpath [Fri, 30 Jan 2015 05:42:51 +0000 (14:42 +0900)]
ched: Ignore offline CPUs in HMP migration & load stats

Previously, an offline CPU would always appear to have a zero load
and this would distort the offload functionality used for balancing
big and little domains.

Maintain a mask of online CPUs in each domain and use this instead.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: Do not ignore grouped tasks during HMP forced migration.
Chris Redpath [Fri, 30 Jan 2015 05:12:26 +0000 (14:12 +0900)]
sched: Do not ignore grouped tasks during HMP forced migration.

If the entity is not a task, it is a cfs group rq. Iterate up to
find the task entity.

Signed-off-by: Chris Redpath <chris.redpath@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoLOCAL / sched: fix build error for smp_plat.h
Chanwoo Choi [Thu, 29 Jan 2015 09:18:13 +0000 (18:18 +0900)]
LOCAL / sched: fix build error for smp_plat.h

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: fix arch_get_fast_and_slow_cpus to get logical cpumask correctly
Sudeep KarkadaNagesha [Thu, 29 Jan 2015 09:08:20 +0000 (18:08 +0900)]
sched: fix arch_get_fast_and_slow_cpus to get logical cpumask correctly

The patch "sched: Use device-tree to provide fast/slow CPU list for HMP"
depends on the ordering of CPU's in the device tree. It breaks to determine
the logical mask correctly if the logical mask of the CPUs differ from
physical ordering in the device tree.

This patch fix the logic by depending on the mpidr in the device tree
and mapping that mpidr to the logical cpu.

Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: Only down migrate low priority tasks if allowed by affinity mask
Morten Rasmussen [Thu, 29 Jan 2015 09:05:30 +0000 (18:05 +0900)]
sched: Only down migrate low priority tasks if allowed by affinity mask

Adds an extra check intersection of the task affinity mask and the slower
hmp_domain cpumask before down migrating low priority tasks.

Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoARM: sched: Avoid empty 'slow' HMP domain
Jon Medhurst [Thu, 29 Jan 2015 09:01:06 +0000 (18:01 +0900)]
ARM: sched: Avoid empty 'slow' HMP domain

On homogeneous (non-heterogeneous) systems all CPUs will be declared
'fast' and the slow cpu list will be empty. In this situation we need to
avoid adding an empty slow HMP domain otherwise the scheduler code will
blow up when it attempts to move a task to the slow domain.

Signed-off-by: Jon Medhurst <tixy@linaro.org>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: Enable HMP priority filter by default
Morten Rasmussen [Thu, 29 Jan 2015 08:53:50 +0000 (17:53 +0900)]
sched: Enable HMP priority filter by default

This updates the ARM Kconfig to enable the HMP priority filter by default.

Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: SCHED_HMP multi-domain task migration control
Morten Rasmussen [Mon, 23 Feb 2015 06:16:54 +0000 (15:16 +0900)]
sched: SCHED_HMP multi-domain task migration control

We need a way to prevent tasks that are migrating up and down the
hmp_domains from migrating straight on through before the load has
adapted to the new compute capacity of the CPU on the new hmp_domain.
This patch adds a next up/down migration delay that prevents the task
from doing another migration in the same direction until the delay
has expired.

Signed-off-by: Morten Rasmussen <Morten.Rasmussen@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: Add HMP task migration ftrace event
Morten Rasmussen [Thu, 29 Jan 2015 08:37:48 +0000 (17:37 +0900)]
sched: Add HMP task migration ftrace event

Adds ftrace event for tracing task migrations using HMP
optimized scheduling.

Signed-off-by: Morten Rasmussen <Morten.Rasmussen@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: Add ftrace events for entity load-tracking
Morten Rasmussen [Thu, 29 Jan 2015 08:32:52 +0000 (17:32 +0900)]
sched: Add ftrace events for entity load-tracking

Adds ftrace events for key variables related to the entity
load-tracking to help debugging scheduler behaviour. Allows tracing
of load contribution and runqueue residency ratio for both entities
and runqueues as well as entity CPU usage ratio.

Signed-off-by: Morten Rasmussen <Morten.Rasmussen@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoARM: sched: Setup SCHED_HMP domains
Morten Rasmussen [Thu, 29 Jan 2015 08:21:04 +0000 (17:21 +0900)]
ARM: sched: Setup SCHED_HMP domains

SCHED_HMP requires the different cpu types to be represented by an
ordered list of hmp_domains. Each hmp_domain represents all cpus of
a particular type using a cpumask.

The list is platform specific and therefore must be generated by
platform code by implementing arch_get_hmp_domains().

Signed-off-by: Morten Rasmussen <Morten.Rasmussen@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoLOCAL / ARM: sched: Add Cortex-A53 compatible as LITTLE core
Chanwoo Choi [Fri, 30 Jan 2015 02:42:27 +0000 (11:42 +0900)]
LOCAL / ARM: sched: Add Cortex-A53 compatible as LITTLE core

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoARM: sched: Use device-tree to provide fast/slow CPU list for HMP
Morten Rasmussen [Thu, 29 Jan 2015 08:14:12 +0000 (17:14 +0900)]
ARM: sched: Use device-tree to provide fast/slow CPU list for HMP

We can't rely on Kconfig options to set the fast and slow CPU lists for
HMP scheduling if we want a single kernel binary to support multiple
devices with different CPU topology. E.g. TC2 (ARM's Test-Chip-2
big.LITTLE system), Fast Models, or even non big.LITTLE
devices.

This patch adds the function arch_get_fast_and_slow_cpus() to generate
the lists at run-time by parsing the CPU nodes in device-tree; it
assumes slow cores are A7s and everything else is fast. The function
still supports the old Kconfig options as this is useful for testing the
HMP scheduler on devices without big.LITTLE.

This patch is reuse of a patch by Jon Medhurst <tixy@linaro.org> with a
few bits left out.

Signed-off-by: Morten Rasmussen <Morten.Rasmussen@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoARM: Add HMP scheduling support for ARM architecture
Morten Rasmussen [Thu, 29 Jan 2015 08:07:28 +0000 (17:07 +0900)]
ARM: Add HMP scheduling support for ARM architecture

Adds Kconfig entries to enable HMP scheduling on ARM platforms.
Currently, it disables CPU level sched_domain load-balacing in order
to simplify things. This needs fixing in a later revision. HMP
scheduling will do the load-balancing at this level instead.

Signed-off-by: Morten Rasmussen <Morten.Rasmussen@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: Introduce priority-based task migration filter
Morten Rasmussen [Thu, 29 Jan 2015 07:59:01 +0000 (16:59 +0900)]
sched: Introduce priority-based task migration filter

Introduces a priority threshold which prevents low priority task
from migrating to faster hmp_domains (cpus). This is useful for
user-space software which assigns lower task priority to background
task.

Signed-off-by: Morten Rasmussen <Morten.Rasmussen@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agoLOCAL / sched: Use {detach|attach}_task becuase of the absence of move_task()
Chanwoo Choi [Wed, 4 Feb 2015 07:26:19 +0000 (16:26 +0900)]
LOCAL / sched: Use {detach|attach}_task becuase of the absence of move_task()

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: Forced task migration on heterogeneous systems
Morten Rasmussen [Thu, 29 Jan 2015 07:55:00 +0000 (16:55 +0900)]
sched: Forced task migration on heterogeneous systems

This patch introduces forced task migration for moving suitable
currently running tasks between hmp_domains. Task behaviour is likely
to change over time. Tasks running in a less capable hmp_domain may
change to become more demanding and should therefore be migrated up.
They are unlikely go through the select_task_rq_fair() path anytime
soon and therefore need special attention.

This patch introduces a period check (SCHED_TICK) of the currently
running task on all runqueues and sets up a forced migration using
stop_machine_no_wait() if the task needs to be migrated.

Ideally, this should not be implemented by polling all runqueues.

Signed-off-by: Morten Rasmussen <Morten.Rasmussen@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: Task placement for heterogeneous systems based on task load-tracking
Morten Rasmussen [Thu, 29 Jan 2015 07:18:12 +0000 (16:18 +0900)]
sched: Task placement for heterogeneous systems based on task load-tracking

This patch introduces the basic SCHED_HMP infrastructure. Each class of
cpus is represented by a hmp_domain and tasks will only be moved between
these domains when their load profiles suggest it is beneficial.

SCHED_HMP relies heavily on the task load-tracking introduced in Paul
Turners fair group scheduling patch set:

<https://lkml.org/lkml/2012/8/23/267>

SCHED_HMP requires that the platform implements arch_get_hmp_domains()
which should set up the platform specific list of hmp_domains. It is
also assumed that the platform disables SD_LOAD_BALANCE for the
appropriate sched_domains.
Tasks placement takes place every time a task is to be inserted into
a runqueue based on its load history. The task placement decision is
based on load thresholds.

There are no restrictions on the number of hmp_domains, however,
multiple (>2) has not been tested and the up/down migration policy is
rather simple.

Signed-off-by: Morten Rasmussen <Morten.Rasmussen@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: entity load-tracking load_avg_ratio
Morten Rasmussen [Thu, 29 Jan 2015 07:05:42 +0000 (16:05 +0900)]
sched: entity load-tracking load_avg_ratio

This patch adds load_avg_ratio to each task. The load_avg_ratio is a
variant of load_avg_contrib which is not scaled by the task priority. It
is calculated like this:

runnable_avg_sum * NICE_0_LOAD / (runnable_avg_period + 1).

Signed-off-by: Morten Rasmussen <Morten.Rasmussen@arm.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agosched: implement usage tracking
Paul Turner [Thu, 29 Jan 2015 06:58:30 +0000 (15:58 +0900)]
sched: implement usage tracking

With the frame-work for runnable tracking now fully in place.  Per-entity usage
tracking is a simple and low-overhead addition.

Signed-off-by: Paul Turner <pjt@google.com>
Reviewed-by: Ben Segall <bsegall@google.com>
[k.kozlowski: rebased on 4.1, no signed-off-by of previous committer]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
7 years agotty: serial: samsung: set flags for use autoCTS mode
Beomho Seo [Wed, 4 Mar 2015 06:34:47 +0000 (15:34 +0900)]
tty: serial: samsung: set flags for use autoCTS mode

This patch have dependency below,
391f93f serial: core: Rework hw-assited flow control support
Acordding to avobe patch serial drivers which enable H/W autoCTS mode must set
UPSTAT_AUTOCTS to prevent the serial core from inadvertently disabling tx.
So, This patch add set/reset UPSTAT_AUTOCTS flag.

Signed-off-by: Beomho Seo <beomho.seo@samsung.com>
7 years agoLOCAL / ASoC: samsung: enable LPASS uart interrupt
Beomho Seo [Thu, 26 Feb 2015 08:54:50 +0000 (17:54 +0900)]
LOCAL / ASoC: samsung: enable LPASS uart interrupt

This patch enable LPASS uart interrupt for use bluetooth.
Bluetooth system use aud-uart.

Signed-off-by: Beomho Seo <beomho.seo@samsung.com>
7 years agoLOCAL / net: rfkill: add rfkill-bcm driver
Beomho Seo [Thu, 26 Feb 2015 08:08:59 +0000 (17:08 +0900)]
LOCAL / net: rfkill: add rfkill-bcm driver

This patch add rfkill-bcm driver for specific control Broadcom bluetooth
chip. This is based rfkill-gpio driver. This driver control on/off
Broadcom bluetooth chip, handle interrupt and notify.

Signed-off-by: Beomho Seo <beomho.seo@samsung.com>
7 years agoLOCAL / bluetooth: add hci event notification
Beomho Seo [Mon, 23 Feb 2015 08:00:31 +0000 (17:00 +0900)]
LOCAL / bluetooth: add hci event notification

For specific hci events, operations are needed. So this patch adds
event notification and its notifier registration.

Signed-off-by: Beomho Seo <beomho.seo@samsung.com>
7 years agoLOCAL / serial: samsung: fix maximum baudrate
Seung-Woo Kim [Thu, 15 May 2014 03:35:50 +0000 (12:35 +0900)]
LOCAL / serial: samsung: fix maximum baudrate

To support hs uart, maximum baudrate is fixed to 3Mbps.

Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
7 years agoleds: add support for MAX77843 led control driver
Jaewon Kim [Fri, 6 Feb 2015 01:25:44 +0000 (10:25 +0900)]
leds: add support for MAX77843 led control driver

This patch adds MAX77843 led driver.
Maxim Max77843 has 4-channel led controller on
MAX77843 MFD(Multi Function Device).

Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
7 years agomfd: max77843: Add led of_compatible in mfd_cell
Jaewon Kim [Fri, 6 Feb 2015 01:23:46 +0000 (10:23 +0900)]
mfd: max77843: Add led of_compatible in mfd_cell

This patch add of_compatible for led driver using device tree.

Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
7 years agoLOCAL / sensors: add max86902 HRM and UV sensor driver
Jaewon Kim [Mon, 9 Mar 2015 08:21:23 +0000 (17:21 +0900)]
LOCAL / sensors: add max86902 HRM and UV sensor driver

This patch adds max86902 HRM(Heart Rate Monitor) and
UV(Ultraviolet Ray) sensor driver.
This driver supports via sensors core driver.

Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
7 years agoLOCAL / sensors: add sensor_core driver
Jaewon Kim [Wed, 11 Mar 2015 02:46:19 +0000 (11:46 +0900)]
LOCAL / sensors: add sensor_core driver

This patch adds to support "/sys/class/sensors" node.
sensors node shared with sensorhub driver and
each sensor for TIZEN platform. So, sensorhub driver merged with
this sensors driver.

Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
7 years agoLOCAL / misc: add support for ice4_irda driver to use IrDA control
Jaewon Kim [Tue, 24 Feb 2015 05:41:15 +0000 (14:41 +0900)]
LOCAL / misc: add support for ice4_irda driver to use IrDA control

This patch add ice4_irda driver to control IrDA(Infrared Data Association)
FPGA(Field Programmable Gate Array) controller.

Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
7 years agoLOCAL / sec_sysfs: sec_class driver
Jaewon Kim [Tue, 24 Feb 2015 05:06:12 +0000 (14:06 +0900)]
LOCAL / sec_sysfs: sec_class driver

sec_sysfs driver create sysfs node and device in "/dev/class/sec/".
It is used for TIZEN platform specific drivers.

Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
7 years agoLOCAL / ARM: dts: Add sensorhub/IrDA dt node for rinato board
Jaewon Kim [Tue, 24 Feb 2015 06:52:21 +0000 (15:52 +0900)]
LOCAL / ARM: dts: Add sensorhub/IrDA dt node for rinato board

This patch Adds sensorhub dt node using
SPI(Serial Peripheral Interface) to communicate with MCU.

Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>