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23153 commits

Author SHA1 Message Date
Morten Rasmussen
f3f132b8e5 UPSTREAM: sched/fair: Consider spare capacity in find_idlest_group()
In low-utilization scenarios comparing relative loads in
find_idlest_group() doesn't always lead to the most optimum choice.
Systems with groups containing different numbers of cpus and/or cpus of
different compute capacity are significantly better off when considering
spare capacity rather than relative load in those scenarios.

In addition to existing load based search an alternative spare capacity
based candidate sched_group is found and selected instead if sufficient
spare capacity exists. If not, existing behaviour is preserved.

Change-Id: I6097af76c302a5a12e240ca24c70f707ad118242
Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: freedom.tan@mediatek.com
Cc: keita.kobayashi.ym@renesas.com
Cc: mgalbraith@suse.de
Cc: sgurrappadi@nvidia.com
Cc: vincent.guittot@linaro.org
Cc: yuyang.du@intel.com
Link: http://lkml.kernel.org/r/1476452472-24740-3-git-send-email-morten.rasmussen@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
(cherry picked from commit 6a0b19c0f39a7a7b7fb77d3867a733136ff059a3)
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
2017-06-02 08:01:52 -07:00
Morten Rasmussen
68c27298cd UPSTREAM: sched/fair: Compute task/cpu utilization at wake-up correctly
At task wake-up load-tracking isn't updated until the task is enqueued.
The task's own view of its utilization contribution may therefore not be
aligned with its contribution to the cfs_rq load-tracking which may have
been updated in the meantime. Basically, the task's own utilization
hasn't yet accounted for the sleep decay, while the cfs_rq may have
(partially). Estimating the cfs_rq utilization in case the task is
migrated at wake-up as task_rq(p)->cfs.avg.util_avg - p->se.avg.util_avg
is therefore incorrect as the two load-tracking signals aren't time
synchronized (different last update).

To solve this problem, this patch synchronizes the task utilization with
its previous rq before the task utilization is used in the wake-up path.
Currently the update/synchronization is done _after_ the task has been
placed by select_task_rq_fair(). The synchronization is done without
having to take the rq lock using the existing mechanism used in
remove_entity_load_avg().

Change-Id: I5605cca0c94c6ba43d9ce11554765a2456cf85bc
Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: freedom.tan@mediatek.com
Cc: keita.kobayashi.ym@renesas.com
Cc: mgalbraith@suse.de
Cc: sgurrappadi@nvidia.com
Cc: vincent.guittot@linaro.org
Cc: yuyang.du@intel.com
Link: http://lkml.kernel.org/r/1476452472-24740-2-git-send-email-morten.rasmussen@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
(cherry picked from commit 104cb16d9eb684f071d5bf3aa87c0d01af259b7c)
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
2017-06-02 08:01:52 -07:00
Morten Rasmussen
abfff9dece UPSTREAM: sched/fair: Let asymmetric CPU configurations balance at wake-up
Currently, SD_WAKE_AFFINE always takes priority over wakeup balancing if
SD_BALANCE_WAKE is set on the sched_domains. For asymmetric
configurations SD_WAKE_AFFINE is only desirable if the waking task's
compute demand (utilization) is suitable for the waking CPU and the
previous CPU, and all CPUs within their respective
SD_SHARE_PKG_RESOURCES domains (sd_llc). If not, let wakeup balancing
take over (find_idlest_{group, cpu}()).

This patch makes affine wake-ups conditional on whether both the waker
CPU and the previous CPU has sufficient capacity for the waking task,
or not, assuming that the CPU capacities within an SD_SHARE_PKG_RESOURCES
domain (sd_llc) are homogeneous.

Change-Id: I6d5d0426713da9ef6198f574ad9afbe58dacc1f0
Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: freedom.tan@mediatek.com
Cc: keita.kobayashi.ym@renesas.com
Cc: mgalbraith@suse.de
Cc: sgurrappadi@nvidia.com
Cc: yuyang.du@intel.com
Link: http://lkml.kernel.org/r/1469453670-2660-10-git-send-email-morten.rasmussen@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
(cherry picked from commit 3273163c6775c4c21823985304c2364b08ca6ea2)
[removed existing definition of capacity_margin]
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
2017-06-02 08:01:52 -07:00
Morten Rasmussen
5173a85e22 UPSTREAM: sched/core: Enable SD_BALANCE_WAKE for asymmetric capacity systems
A domain with the SD_ASYM_CPUCAPACITY flag set indicate that
sched_groups at this level and below do not include CPUs of all
capacities available (e.g. group containing little-only or big-only CPUs
in big.LITTLE systems). It is therefore necessary to put in more effort
in finding an appropriate CPU at task wake-up by enabling balancing at
wake-up (SD_BALANCE_WAKE) on all lower (child) levels.

Change-Id: I4615917f540d03d7e7ef7de8f0da33b1ad97387c
Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: freedom.tan@mediatek.com
Cc: keita.kobayashi.ym@renesas.com
Cc: mgalbraith@suse.de
Cc: sgurrappadi@nvidia.com
Cc: vincent.guittot@linaro.org
Cc: yuyang.du@intel.com
Link: http://lkml.kernel.org/r/1469453670-2660-8-git-send-email-morten.rasmussen@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
(cherry picked from commit 9ee1cda5ee25c7dd82acf25892e0d229e818f8c7)
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
2017-06-02 08:01:52 -07:00
Morten Rasmussen
e51c057694 UPSTREAM: sched/core: Pass child domain into sd_init()
If behavioural sched_domain flags depend on topology flags set at higher
domain levels we need a way to update the child domain flags. Moving the
child pointer assignment inside sd_init() should make that possible.

Change-Id: If043921fdf102c310adcc9e0280afa33c48c4783
Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: freedom.tan@mediatek.com
Cc: keita.kobayashi.ym@renesas.com
Cc: mgalbraith@suse.de
Cc: sgurrappadi@nvidia.com
Cc: vincent.guittot@linaro.org
Cc: yuyang.du@intel.com
Link: http://lkml.kernel.org/r/1469453670-2660-7-git-send-email-morten.rasmussen@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
(cherry picked from commit 3676b13e8524c576825fe1e731e347dba0083888)
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
2017-06-02 08:01:52 -07:00
Morten Rasmussen
68a3b157d9 UPSTREAM: sched/core: Introduce SD_ASYM_CPUCAPACITY sched_domain topology flag
Add a topology flag to the sched_domain hierarchy indicating the lowest
domain level where the full range of CPU capacities is represented by
the domain members for asymmetric capacity topologies (e.g. ARM
big.LITTLE).

The flag is intended to indicate that extra care should be taken when
placing tasks on CPUs and this level spans all the different types of
CPUs found in the system (no need to look further up the domain
hierarchy). This information is currently only available through
iterating through the capacities of all the CPUs at parent levels in the
sched_domain hierarchy.

  SD 2      [  0      1      2      3]  SD_ASYM_CPUCAPACITY

  SD 1      [  0      1] [   2      3]  !SD_ASYM_CPUCAPACITY

  CPU:         0      1      2      3
  capacity:  756    756   1024   1024

If the topology in the example above is duplicated to create an eight
CPU example with third sched_domain level on top (SD 3), this level
should not have the flag set (!SD_ASYM_CPUCAPACITY) as its two group
would both have all CPU capacities represented within them.

Change-Id: I1526407b90567cac387419719b7d7fdc8b259a85
Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: freedom.tan@mediatek.com
Cc: keita.kobayashi.ym@renesas.com
Cc: mgalbraith@suse.de
Cc: sgurrappadi@nvidia.com
Cc: vincent.guittot@linaro.org
Cc: yuyang.du@intel.com
Link: http://lkml.kernel.org/r/1469453670-2660-6-git-send-email-morten.rasmussen@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
(cherry picked from commit 1f6e6c7cb9bcd58abb5ee11243e0eefe6b36fc8e)
[trivial merge conflict]
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
2017-06-02 08:01:52 -07:00
Morten Rasmussen
3e9cdd5ae9 UPSTREAM: sched/core: Remove unnecessary NULL-pointer check
Checking if the sched_domain pointer returned by sd_init() is NULL seems
pointless as sd_init() neither checks if it is valid to begin with nor
set it to NULL.

Change-Id: I5e16fd0c2ca7234b097be7c95409ddb15c5e9de9
Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: freedom.tan@mediatek.com
Cc: keita.kobayashi.ym@renesas.com
Cc: mgalbraith@suse.de
Cc: sgurrappadi@nvidia.com
Cc: vincent.guittot@linaro.org
Cc: yuyang.du@intel.com
Link: http://lkml.kernel.org/r/1469453670-2660-5-git-send-email-morten.rasmussen@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
(cherry picked from commit 0e6d2a67a41321b3ef650b780a279a37855de08e)
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
2017-06-02 08:01:51 -07:00
Morten Rasmussen
bc7c939b3a UPSTREAM: sched/fair: Optimize find_idlest_cpu() when there is no choice
In the current find_idlest_group()/find_idlest_cpu() search we end up
calling find_idlest_cpu() in a sched_group containing only one CPU in
the end. Checking idle-states becomes pointless when there is no
alternative, so bail out instead.

Change-Id: Ic62bf09b53a7984143ac2431aaa69c69b204cd56
Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: linux-kernel@vger.kernel.org
Cc: mgalbraith@suse.de
Cc: vincent.guittot@linaro.org
Cc: yuyang.du@intel.com
Link: http://lkml.kernel.org/r/1466615004-3503-4-git-send-email-morten.rasmussen@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
(cherry picked from commit eaecf41f5abf80b63c8e025fcb9ee4aa203c3038)
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
2017-06-02 08:01:51 -07:00
Morten Rasmussen
3bb3d7e7d9 BACKPORT: sched/fair: Make the use of prev_cpu consistent in the wakeup path
In commit:

  ac66f54772 ("sched/numa: Introduce migrate_swap()")

select_task_rq() got a 'cpu' argument to enable overriding of prev_cpu
in special cases (NUMA task swapping).

However, the select_task_rq_fair() helper functions: wake_affine() and
select_idle_sibling(), still use task_cpu(p) directly to work out
prev_cpu, which leads to inconsistencies.

This patch passes prev_cpu (potentially overridden by NUMA code) into
the helper functions to ensure prev_cpu is indeed the same CPU
everywhere in the wakeup path.

Change-Id: I4951c4eead2e6045e4fb34e89f6cda17d881d4d7
cc: Ingo Molnar <mingo@redhat.com>
cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: linux-kernel@vger.kernel.org
Cc: mgalbraith@suse.de
Cc: vincent.guittot@linaro.org
Cc: yuyang.du@intel.com
Link: http://lkml.kernel.org/r/1466615004-3503-3-git-send-email-morten.rasmussen@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
(cherry picked from commit 772bd008cd9a1d4e8ce566f2edcc61d1c28fcbe5)
[merged with Android/EAS wakeup path]
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
2017-06-02 08:01:51 -07:00
Dietmar Eggemann
cb88574a68 Partial Revert: "WIP: sched: Add cpu capacity awareness to wakeup balancing"
Revert the changes in find_idlest_cpu() and find_idlest_group().

Keep the infrastructure bits which are used in following EAS patches.

Change-Id: Id516ca5f3e51b9a13db1ebb8de2df3aa25f9679b
Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
2017-06-02 08:01:51 -07:00
Dietmar Eggemann
bd6ff3505f Revert "WIP: sched: Consider spare cpu capacity at task wake-up"
This reverts commit 75a9695b619741019363f889c99c97c7bb823797.

Change-Id: I846b21f2bdeb0b0ca30ad65683564ed07a429428
Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
[ minor merge changes ]
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
2017-06-02 08:01:51 -07:00
Viresh Kumar
5c015afebd FROM-LIST: cpufreq: schedutil: Redefine the rate_limit_us tunable
The rate_limit_us tunable is intended to reduce the possible overhead
from running the schedutil governor.  However, that overhead can be
divided into two separate parts: the governor computations and the
invocation of the scaling driver to set the CPU frequency.  The latter
is where the real overhead comes from.  The former is much less
expensive in terms of execution time and running it every time the
governor callback is invoked by the scheduler, after rate_limit_us
interval has passed since the last frequency update, would not be a
problem.

For this reason, redefine the rate_limit_us tunable so that it means the
minimum time that has to pass between two consecutive invocations of the
scaling driver by the schedutil governor (to set the CPU frequency).

Change-Id: Iced64116b826c25441ef537c27a3dabfcf81919e
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
[pulled from linux-pm linux-next https://patchwork.kernel.org/patch/9583949/ ]
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
2017-06-02 08:01:51 -07:00
Steve Muckle
51b20b214f cpufreq: schedutil: add up/down frequency transition rate limits
The rate-limit tunable in the schedutil governor applies to transitions
to both lower and higher frequencies. On several platforms it is not the
ideal tunable though, as it is difficult to get best power/performance
figures using the same limit in both directions.

It is common on mobile platforms with demanding user interfaces to want
to increase frequency rapidly for example but decrease slowly.

One of the example can be a case where we have short busy periods
followed by similar or longer idle periods. If we keep the rate-limit
high enough, we will not go to higher frequencies soon enough. On the
other hand, if we keep it too low, we will have too many frequency
transitions, as we will always reduce the frequency after the busy
period.

It would be very useful if we can set low rate-limit while increasing
the frequency (so that we can respond to the short busy periods quickly)
and high rate-limit while decreasing frequency (so that we don't reduce
the frequency immediately after the short busy period and that may avoid
frequency transitions before the next busy period).

Implement separate up/down transition rate limits. Note that the
governor avoids frequency recalculations for a period equal to minimum
of up and down rate-limit. A global mutex is also defined to protect
updates to min_rate_limit_us via two separate sysfs files.

Note that this wouldn't change behavior of the schedutil governor for
the platforms which wish to keep same values for both up and down rate
limits.

This is tested with the rt-app [1] on ARM Exynos, dual A15 processor
platform.

Testcase: Run a SCHED_OTHER thread on CPU0 which will emulate work-load
for X ms of busy period out of the total period of Y ms, i.e. Y - X ms
of idle period. The values of X/Y taken were: 20/40, 20/50, 20/70, i.e
idle periods of 20, 30 and 50 ms respectively. These were tested against
values of up/down rate limits as: 10/10 ms and 10/40 ms.

For every test we noticed a performance increase of 5-10% with the
schedutil governor, which was very much expected.

[Viresh]: Simplified user interface and introduced min_rate_limit_us +
	      mutex, rewrote commit log and included test results.

[1] https://github.com/scheduler-tools/rt-app/

Change-Id: I18720a83855b196b8e21dcdc8deae79131635b84
Signed-off-by: Steve Muckle <smuckle.linux@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
(applied from https://marc.info/?l=linux-kernel&m=147936011103832&w=2)
[trivial adaptations]
Signed-off-by: Juri Lelli <juri.lelli@arm.com>
2017-06-02 08:01:51 -07:00
Juri Lelli
f71d9f01c6 sched/cpufreq: make schedutil use WALT signal
If WALT is available and enabled, make schedutil governor use its
utilization signal.

Change-Id: I92bc37989447a76616e9bcc4e9e8616774fb9925
Signed-off-by: Juri Lelli <juri.lelli@arm.com>
[we need to use boosted_cpu_util for schedutil, so make it
 not static]
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
2017-06-02 08:01:51 -07:00
Steve Muckle
e5da6c11b2 sched: cpufreq: use rt_avg as estimate of required RT CPU capacity
A policy of going to fmax on any RT activity will be detrimental
for power on many platforms. Often RT accounts for only a small amount
of CPU activity so sending the CPU frequency to fmax is overkill. Worse
still, some platforms may not be able to even complete the CPU frequency
change before the RT activity has already completed.

Cpufreq governors have not treated RT activity this way in the past so
it is not part of the expected semantics of the RT scheduling class. The
DL class offers guarantees about task completion and could be used for
this purpose.

Modify the schedutil algorithm to instead use rt_avg as an estimate of
RT utilization of the CPU.

Based on previous work by Vincent Guittot <vincent.guittot@linaro.org>.

Change-Id: I1ed605a3e2512a94d34217a8e57c3fd97cca60be
Signed-off-by: Steve Muckle <smuckle@linaro.org>
2017-06-02 08:01:51 -07:00
Viresh Kumar
e2aa75a4c7 cpufreq: schedutil: move slow path from workqueue to SCHED_FIFO task
If slow path frequency changes are conducted in a SCHED_OTHER context
then they may be delayed for some amount of time, including
indefinitely, when real time or deadline activity is taking place.

Move the slow path to a real time kernel thread. In the future the
thread should be made SCHED_DEADLINE. The RT priority is arbitrarily set
to 50 for now.

Hackbench results on ARM Exynos, dual core A15 platform for 10
iterations:

$ hackbench -s 100 -l 100 -g 10 -f 20

Before			After
---------------------------------
1.808			1.603
1.847			1.251
2.229			1.590
1.952			1.600
1.947			1.257
1.925			1.627
2.694			1.620
1.258			1.621
1.919			1.632
1.250			1.240

Average:

1.8829			1.5041

Based on initial work by Steve Muckle.

Change-Id: I8f53037e94f353960c6d10abf07822d671631ef7
Signed-off-by: Steve Muckle <smuckle.linux@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
(cherry picked from 02a7b1ee3baa)
[adapt to the 3.18 kthread interface]
Signed-off-by: Juri Lelli <juri.lelli@arm.com>
2017-06-02 08:01:51 -07:00
Petr Mladek
78213729a7 BACKPORT: kthread: allow to cancel kthread work
We are going to use kthread workers more widely and sometimes we will need
to make sure that the work is neither pending nor running.

This patch implements cancel_*_sync() operations as inspired by
workqueues.  Well, we are synchronized against the other operations via
the worker lock, we use del_timer_sync() and a counter to count parallel
cancel operations.  Therefore the implementation might be easier.

First, we check if a worker is assigned.  If not, the work has newer been
queued after it was initialized.

Second, we take the worker lock.  It must be the right one.  The work must
not be assigned to another worker unless it is initialized in between.

Third, we try to cancel the timer when it exists.  The timer is deleted
synchronously to make sure that the timer call back is not running.  We
need to temporary release the worker->lock to avoid a possible deadlock
with the callback.  In the meantime, we set work->canceling counter to
avoid any queuing.

Fourth, we try to remove the work from a worker list. It might be
the list of either normal or delayed works.

Fifth, if the work is running, we call kthread_flush_work().  It might
take an arbitrary time.  We need to release the worker-lock again.  In the
meantime, we again block any queuing by the canceling counter.

As already mentioned, the check for a pending kthread work is done under a
lock.  In compare with workqueues, we do not need to fight for a single
PENDING bit to block other operations.  Therefore we do not suffer from
the thundering storm problem and all parallel canceling jobs might use
kthread_flush_work().  Any queuing is blocked until the counter gets zero.

Change-Id: I8a8ece0f93c828f311d0ad5c88d80db2388e4808
Link: http://lkml.kernel.org/r/1470754545-17632-10-git-send-email-pmladek@suse.com
Signed-off-by: Petr Mladek <pmladek@suse.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry-picked from 37be45d49dec2a411e29d50c9597cfe8184b5645)
[major changes to the original patch while cherry-picking; only rebased
the sync variant]
Signed-off-by: Juri Lelli <juri.lelli@arm.com>
2017-06-02 08:01:50 -07:00
Steve Muckle
ca7b7d3c99 sched/cpufreq: fix tunables for schedfreq governor
The schedfreq governor does not currently handle cpufreq drivers which
use a global set of tunables (!have_governor_per_policy).

For example on x86 and using the acpi cpufreq driver, doing this

  cat /sys/devices/system/cpu/cpufreq/sched/up_throttle_nsec

will result in a bad pointer access.

Update the tunable code using the upstream schedutil tunable code by
Rafael Wysocki as a guide.

Includes a partial backport of the reorganized cpufreq tunable
infrastructure.

Change-Id: I7e6f8de1dac297077ad43f37dd2f6ddbfe921c98
Signed-off-by: Steve Muckle <smuckle@linaro.org>
[fixed cherry-pick issue]
Signed-off-by: Juri Lelli <juri.lelli@arm.com>
[fixed cherry-pick issue]
Signed-off-by: Thierry Strudel <tstrudel@google.com>
2017-06-02 08:01:50 -07:00
Steve Muckle
6bc6115c16 BACKPORT: cpufreq: schedutil: New governor based on scheduler utilization data
Add a new cpufreq scaling governor, called "schedutil", that uses
scheduler-provided CPU utilization information as input for making
its decisions.

Doing that is possible after commit 34e2c55 (cpufreq: Add
mechanism for registering utilization update callbacks) that
introduced cpufreq_update_util() called by the scheduler on
utilization changes (from CFS) and RT/DL task status updates.
In particular, CPU frequency scaling decisions may be based on
the the utilization data passed to cpufreq_update_util() by CFS.

The new governor is relatively simple.

The frequency selection formula used by it depends on whether or not
the utilization is frequency-invariant.  In the frequency-invariant
case the new CPU frequency is given by

	next_freq = 1.25 * max_freq * util / max

where util and max are the last two arguments of cpufreq_update_util().
In turn, if util is not frequency-invariant, the maximum frequency in
the above formula is replaced with the current frequency of the CPU:

	next_freq = 1.25 * curr_freq * util / max

The coefficient 1.25 corresponds to the frequency tipping point at
(util / max) = 0.8.

All of the computations are carried out in the utilization update
handlers provided by the new governor.  One of those handlers is
used for cpufreq policies shared between multiple CPUs and the other
one is for policies with one CPU only (and therefore it doesn't need
to use any extra synchronization means).

The governor supports fast frequency switching if that is supported
by the cpufreq driver in use and possible for the given policy.
In the fast switching case, all operations of the governor take
place in its utilization update handlers.  If fast switching cannot
be used, the frequency switch operations are carried out with the
help of a work item which only calls __cpufreq_driver_target()
(under a mutex) to trigger a frequency update (to a value already
computed beforehand in one of the utilization update handlers).

Currently, the governor treats all of the RT and DL tasks as
"unknown utilization" and sets the frequency to the allowed
maximum when updated from the RT or DL sched classes.  That
heavy-handed approach should be replaced with something more
subtle and specifically targeted at RT and DL tasks.

The governor shares some tunables management code with the
"ondemand" and "conservative" governors and uses some common
definitions from cpufreq_governor.h, but apart from that it
is stand-alone.

Change-Id: I03876e622768e4b3ee4dc28682af7cce771f2f4c
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
(cherry-picked from 9bdcb44e391da5c41b98573bf0305a0e0b1c9569)
[ Backport the schedutil cpufreq governor from 4.9. Some cpufreq
  tunable infrastructure as well as the resolve_freq API is also
  backported as those are dependencies]
Signed-off-by: Steve Muckle <smuckle@linaro.org>
[trivial cherry-picking fixes]
Signed-off-by: Juri Lelli <juri.lelli@arm.com>
[fixed default governor machinery]
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
2017-06-02 08:01:50 -07:00
Steve Muckle
f02702dcf2 sched: backport cpufreq hooks from 4.9-rc4
The scheduler cpufreq hooks are required by the schedutil cpufreq
governor.

Change-Id: Ied6c46262bb33b7e81bbb3d3d2761124e0c676b7
Signed-off-by: Steve Muckle <smuckle@linaro.org>
[trivial cherry-picking fixes]
Signed-off-by: Juri Lelli <juri.lelli@arm.com>
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
2017-06-02 08:01:50 -07:00
Linux Build Service Account
09f613d5b5 Merge "core_ctl: Add sysfs node to disable core_ctl" 2017-06-01 23:49:00 -07:00
Vikram Mulukutla
259636e7d0 sched: hmp: Optimize cycle counter reads
The cycle counter read is a bit of an expensive operation and requires
locking across all CPUs in a cluster. Optimize this by returning the
same value if the delta between two reads is zero (so if two reads are
done in the same sched context) or if the last read was within a
specific time period prior to the current read.

Change-Id: I99da5a704d3652f53c8564ba7532783d3288f227
Signed-off-by: Vikram Mulukutla <markivx@codeaurora.org>
2017-05-31 18:16:30 -07:00
Prasad Sodagudi
0958ceaaf4 drivers: Warning fixes to disable CC_OPTIMIZE_FOR_SIZE
These are all driver changes needed for disablement of
CONFIG_CC_OPTIMIZE_FOR_SIZE. CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
is enabled by default once CONFIG_CC_OPTIMIZE_FOR_SIZE is disabled.

Change-Id: Ia46a1f24e8a082a29ea6151e41e6d3a85a05fd4f
Signed-off-by: Prasad Sodagudi <psodagud@codeaurora.org>
Signed-off-by: Sridhar Parasuram <sridhar@codeaurora.org>
2017-05-31 16:51:47 -07:00
Pavankumar Kondeti
57fd979fc9 core_ctl: un-isolate BIG CPUs more aggressively
The current algorithm to bring additional BIG CPUs is very
conservative. It works when BIG tasks alone run on BIG
cluster. When co-location and scheduler boost features
are activated, small/medium tasks also run on BIG cluster.
We don't want these tasks to downmigrate, when BIG CPUs are
available but isolated. The following changes are done to
un-isolate CPUs more aggressively.

(1) Round up the big_avg. When the big_avg indicates that
there are 1.5 tasks on an average in the last window, it
indicates that we need 2 BIG CPUs not 1 BIG CPU.

(2) Track the maximum number of running tasks in the last
window on all CPUs. If any of the CPU in a cluster has more
than 4 runnable tasks in the last window, bring an additional
CPU to help out.

Change-Id: Id05d9983af290760cec6d93d1bdc45bc5e924cce
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
2017-05-31 08:33:48 +05:30
Pavankumar Kondeti
f37f0680d7 sched: Improve short sleeping tasks detection
When a short sleeping task goes for a long sleep, the task's
avg_sleep_time signal gets boosted. This signal will not go
below short_sleep threshold for a long time time even when the
task run in short bursts. This results in frequent preemption
of other tasks as the short burst tasks are placed on busy CPUs.

The idea behind tracking avg_sleep_time signal is to detect if a
task is short sleeping or not. Limit the sleep time to twice the
short sleep threshold to make avg_sleep_time signal more responsive.
This won't affect regular long sleeping tasks, as the avg_sleep_time
would be higher than threshold.

Change-Id: Ic0838e81ef7f5d83864a58b318553afc42812853
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
2017-05-31 08:30:01 +05:30
Linux Build Service Account
ec7abeae1a Merge "time: Remove CONFIG_TIMER_STATS" 2017-05-26 21:11:04 -07:00
Sabyasachi Singh
a43e9b1d23 core_ctl: Add sysfs node to disable core_ctl
This core ctl enable sysfs node can be used to enable
and disable the core isolation by core ctl in runtime
for the cluster. By default enable is set to 1, core
ctl is enabled. if this gets set to 0 then isolated
cores, if any, would get available to scheduler for
load balancing and core_ctl will not do any core
isolation.

Change-Id: I856ec9358f3ceb781468e2537b4d086e4d4600f0
Signed-off-by: Sabyasachi Singh <sssingh@codeaurora.org>
2017-05-26 18:11:59 -07:00
Greg Kroah-Hartman
9bc462220d This is the 4.4.70 stable release
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Merge 4.4.70 into android-4.4

Changes in 4.4.70
	usb: misc: legousbtower: Fix buffers on stack
	usb: misc: legousbtower: Fix memory leak
	USB: ene_usb6250: fix DMA to the stack
	watchdog: pcwd_usb: fix NULL-deref at probe
	char: lp: fix possible integer overflow in lp_setup()
	USB: core: replace %p with %pK
	ARM: tegra: paz00: Mark panel regulator as enabled on boot
	tpm_crb: check for bad response size
	infiniband: call ipv6 route lookup via the stub interface
	dm btree: fix for dm_btree_find_lowest_key()
	dm raid: select the Kconfig option CONFIG_MD_RAID0
	dm bufio: avoid a possible ABBA deadlock
	dm bufio: check new buffer allocation watermark every 30 seconds
	dm cache metadata: fail operations if fail_io mode has been established
	dm bufio: make the parameter "retain_bytes" unsigned long
	dm thin metadata: call precommit before saving the roots
	dm space map disk: fix some book keeping in the disk space map
	md: update slab_cache before releasing new stripes when stripes resizing
	rtlwifi: rtl8821ae: setup 8812ae RFE according to device type
	mwifiex: pcie: fix cmd_buf use-after-free in remove/reset
	ima: accept previously set IMA_NEW_FILE
	KVM: x86: Fix load damaged SSEx MXCSR register
	KVM: X86: Fix read out-of-bounds vulnerability in kvm pio emulation
	regulator: tps65023: Fix inverted core enable logic.
	s390/kdump: Add final note
	s390/cputime: fix incorrect system time
	ath9k_htc: Add support of AirTies 1eda:2315 AR9271 device
	ath9k_htc: fix NULL-deref at probe
	drm/amdgpu: Avoid overflows/divide-by-zero in latency_watermark calculations.
	drm/amdgpu: Make display watermark calculations more accurate
	drm/nouveau/therm: remove ineffective workarounds for alarm bugs
	drm/nouveau/tmr: ack interrupt before processing alarms
	drm/nouveau/tmr: fix corruption of the pending list when rescheduling an alarm
	drm/nouveau/tmr: avoid processing completed alarms when adding a new one
	drm/nouveau/tmr: handle races with hw when updating the next alarm time
	cdc-acm: fix possible invalid access when processing notification
	proc: Fix unbalanced hard link numbers
	of: fix sparse warning in of_pci_range_parser_one
	iio: dac: ad7303: fix channel description
	pid_ns: Sleep in TASK_INTERRUPTIBLE in zap_pid_ns_processes
	pid_ns: Fix race between setns'ed fork() and zap_pid_ns_processes()
	USB: serial: ftdi_sio: fix setting latency for unprivileged users
	USB: serial: ftdi_sio: add Olimex ARM-USB-TINY(H) PIDs
	ext4 crypto: don't let data integrity writebacks fail with ENOMEM
	ext4 crypto: fix some error handling
	net: qmi_wwan: Add SIMCom 7230E
	fscrypt: fix context consistency check when key(s) unavailable
	f2fs: check entire encrypted bigname when finding a dentry
	fscrypt: avoid collisions when presenting long encrypted filenames
	sched/fair: Do not announce throttled next buddy in dequeue_task_fair()
	sched/fair: Initialize throttle_count for new task-groups lazily
	usb: host: xhci-plat: propagate return value of platform_get_irq()
	xhci: apply PME_STUCK_QUIRK and MISSING_CAS quirk for Denverton
	usb: host: xhci-mem: allocate zeroed Scratchpad Buffer
	net: irda: irda-usb: fix firmware name on big-endian hosts
	usbvision: fix NULL-deref at probe
	mceusb: fix NULL-deref at probe
	ttusb2: limit messages to buffer size
	usb: musb: tusb6010_omap: Do not reset the other direction's packet size
	USB: iowarrior: fix info ioctl on big-endian hosts
	usb: serial: option: add Telit ME910 support
	USB: serial: qcserial: add more Lenovo EM74xx device IDs
	USB: serial: mct_u232: fix big-endian baud-rate handling
	USB: serial: io_ti: fix div-by-zero in set_termios
	USB: hub: fix SS hub-descriptor handling
	USB: hub: fix non-SS hub-descriptor handling
	ipx: call ipxitf_put() in ioctl error path
	iio: proximity: as3935: fix as3935_write
	ceph: fix recursion between ceph_set_acl() and __ceph_setattr()
	gspca: konica: add missing endpoint sanity check
	s5p-mfc: Fix unbalanced call to clock management
	dib0700: fix NULL-deref at probe
	zr364xx: enforce minimum size when reading header
	dvb-frontends/cxd2841er: define symbol_rate_min/max in T/C fe-ops
	cx231xx-audio: fix init error path
	cx231xx-audio: fix NULL-deref at probe
	cx231xx-cards: fix NULL-deref at probe
	powerpc/book3s/mce: Move add_taint() later in virtual mode
	powerpc/pseries: Fix of_node_put() underflow during DLPAR remove
	powerpc/64e: Fix hang when debugging programs with relocated kernel
	ARM: dts: at91: sama5d3_xplained: fix ADC vref
	ARM: dts: at91: sama5d3_xplained: not all ADC channels are available
	arm64: xchg: hazard against entire exchange variable
	arm64: uaccess: ensure extension of access_ok() addr
	arm64: documentation: document tagged pointer stack constraints
	xc2028: Fix use-after-free bug properly
	mm/huge_memory.c: respect FOLL_FORCE/FOLL_COW for thp
	staging: rtl8192e: fix 2 byte alignment of register BSSIDR.
	staging: rtl8192e: rtl92e_get_eeprom_size Fix read size of EPROM_CMD.
	iommu/vt-d: Flush the IOTLB to get rid of the initial kdump mappings
	metag/uaccess: Fix access_ok()
	metag/uaccess: Check access_ok in strncpy_from_user
	uwb: fix device quirk on big-endian hosts
	genirq: Fix chained interrupt data ordering
	osf_wait4(): fix infoleak
	tracing/kprobes: Enforce kprobes teardown after testing
	PCI: Fix pci_mmap_fits() for HAVE_PCI_RESOURCE_TO_USER platforms
	PCI: Freeze PME scan before suspending devices
	drm/edid: Add 10 bpc quirk for LGD 764 panel in HP zBook 17 G2
	nfsd: encoders mustn't use unitialized values in error cases
	drivers: char: mem: Check for address space wraparound with mmap()
	Linux 4.4.70

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2017-05-25 17:31:28 +02:00
Thomas Gleixner
6384f782a6 tracing/kprobes: Enforce kprobes teardown after testing
commit 30e7d894c1478c88d50ce94ddcdbd7f9763d9cdd upstream.

Enabling the tracer selftest triggers occasionally the warning in
text_poke(), which warns when the to be modified page is not marked
reserved.

The reason is that the tracer selftest installs kprobes on functions marked
__init for testing. These probes are removed after the tests, but that
removal schedules the delayed kprobes_optimizer work, which will do the
actual text poke. If the work is executed after the init text is freed,
then the warning triggers. The bug can be reproduced reliably when the work
delay is increased.

Flush the optimizer work and wait for the optimizing/unoptimizing lists to
become empty before returning from the kprobes tracer selftest. That
ensures that all operations which were queued due to the probes removal
have completed.

Link: http://lkml.kernel.org/r/20170516094802.76a468bb@gandalf.local.home

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Fixes: 6274de498 ("kprobes: Support delayed unoptimizing")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25 14:30:17 +02:00
Thomas Gleixner
e07db0d720 genirq: Fix chained interrupt data ordering
commit 2c4569ca26986d18243f282dd727da27e9adae4c upstream.

irq_set_chained_handler_and_data() sets up the chained interrupt and then
stores the handler data.

That's racy against an immediate interrupt which gets handled before the
store of the handler data happened. The handler will dereference a NULL
pointer and crash.

Cure it by storing handler data before installing the chained handler.

Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25 14:30:17 +02:00
Konstantin Khlebnikov
ada79b5ecd sched/fair: Initialize throttle_count for new task-groups lazily
commit 094f469172e00d6ab0a3130b0e01c83b3cf3a98d upstream.

Cgroup created inside throttled group must inherit current throttle_count.
Broken throttle_count allows to nominate throttled entries as a next buddy,
later this leads to null pointer dereference in pick_next_task_fair().

This patch initialize cfs_rq->throttle_count at first enqueue: laziness
allows to skip locking all rq at group creation. Lazy approach also allows
to skip full sub-tree scan at throttling hierarchy (not in this patch).

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bsegall@google.com
Link: http://lkml.kernel.org/r/146608182119.21870.8439834428248129633.stgit@buzz
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Ben Pineau <benjamin.pineau@mirakl.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25 14:30:12 +02:00
Konstantin Khlebnikov
f01ae9cb0d sched/fair: Do not announce throttled next buddy in dequeue_task_fair()
commit 754bd598be9bbc953bc709a9e8ed7f3188bfb9d7 upstream.

Hierarchy could be already throttled at this point. Throttled next
buddy could trigger a NULL pointer dereference in pick_next_task_fair().

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Ben Segall <bsegall@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/146608183552.21905.15924473394414832071.stgit@buzz
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Ben Pineau <benjamin.pineau@mirakl.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25 14:30:12 +02:00
Kirill Tkhai
6a70a5833e pid_ns: Fix race between setns'ed fork() and zap_pid_ns_processes()
commit 3fd37226216620c1a468afa999739d5016fbc349 upstream.

Imagine we have a pid namespace and a task from its parent's pid_ns,
which made setns() to the pid namespace. The task is doing fork(),
while the pid namespace's child reaper is dying. We have the race
between them:

Task from parent pid_ns             Child reaper
copy_process()                      ..
  alloc_pid()                       ..
  ..                                zap_pid_ns_processes()
  ..                                  disable_pid_allocation()
  ..                                  read_lock(&tasklist_lock)
  ..                                  iterate over pids in pid_ns
  ..                                    kill tasks linked to pids
  ..                                  read_unlock(&tasklist_lock)
  write_lock_irq(&tasklist_lock);   ..
  attach_pid(p, PIDTYPE_PID);       ..
  ..                                ..

So, just created task p won't receive SIGKILL signal,
and the pid namespace will be in contradictory state.
Only manual kill will help there, but does the userspace
care about this? I suppose, the most users just inject
a task into a pid namespace and wait a SIGCHLD from it.

The patch fixes the problem. It simply checks for
(pid_ns->nr_hashed & PIDNS_HASH_ADDING) in copy_process().
We do it under the tasklist_lock, and can't skip
PIDNS_HASH_ADDING as noted by Oleg:

"zap_pid_ns_processes() does disable_pid_allocation()
and then takes tasklist_lock to kill the whole namespace.
Given that copy_process() checks PIDNS_HASH_ADDING
under write_lock(tasklist) they can't race;
if copy_process() takes this lock first, the new child will
be killed, otherwise copy_process() can't miss
the change in ->nr_hashed."

If allocation is disabled, we just return -ENOMEM
like it's made for such cases in alloc_pid().

v2: Do not move disable_pid_allocation(), do not
introduce a new variable in copy_process() and simplify
the patch as suggested by Oleg Nesterov.
Account the problem with double irq enabling
found by Eric W. Biederman.

Fixes: c876ad7682 ("pidns: Stop pid allocation when init dies")
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Ingo Molnar <mingo@kernel.org>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Oleg Nesterov <oleg@redhat.com>
CC: Mike Rapoport <rppt@linux.vnet.ibm.com>
CC: Michal Hocko <mhocko@suse.com>
CC: Andy Lutomirski <luto@kernel.org>
CC: "Eric W. Biederman" <ebiederm@xmission.com>
CC: Andrei Vagin <avagin@openvz.org>
CC: Cyrill Gorcunov <gorcunov@openvz.org>
CC: Serge Hallyn <serge@hallyn.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25 14:30:11 +02:00
Eric W. Biederman
ddf9b92f12 pid_ns: Sleep in TASK_INTERRUPTIBLE in zap_pid_ns_processes
commit b9a985db98961ae1ba0be169f19df1c567e4ffe0 upstream.

The code can potentially sleep for an indefinite amount of time in
zap_pid_ns_processes triggering the hung task timeout, and increasing
the system average.  This is undesirable.  Sleep with a task state of
TASK_INTERRUPTIBLE instead of TASK_UNINTERRUPTIBLE to remove these
undesirable side effects.

Apparently under heavy load this has been allowing Chrome to trigger
the hung time task timeout error and cause ChromeOS to reboot.

Reported-by: Vovo Yang <vovoy@google.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Fixes: 6347e90091 ("pidns: guarantee that the pidns init will be the last pidns process reaped")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25 14:30:11 +02:00
Maulik Shah
4b12a8cc34 genirq: Use irq_set_affinity_locked to change irq affinity
Currently PM QoS is not getting notifications if irq affinity
is changed by core isolation with irq_do_set_affinity.

Use irq_set_affinity_locked instead to get notifications when
updating affinity.

Change-Id: Iab745a23637d9353f730ca77ac7e92cf61b1bf67
Signed-off-by: Maulik Shah <mkshah@codeaurora.org>
2017-05-24 12:44:23 +05:30
Pavankumar Kondeti
3b8631c0d5 hrtimer: Don't drop the base lock when migration during isolation
The current code drops the base lock and wait for the running
hrtimer's expiry event to be processed on the isolated CPU.
This leaves a window, where the running hrtimer can migrate
to a different CPU or even get freed. The pinned hrtimers that
are maintained in a temporarily list also can get freed while
the lock is dropped. The only reason for waiting for the running
hrtimer is to make sure that this hrtimer is migrated away from
the isolated CPU. This is a problem only if this hrtimer gets
rearmed from it's callback. As the possibility of this race is
very rare, it is better to have this limitation instead of fixing
the above mentioned bugs with more intrusive changes.

Change-Id: I14ba67cacb321d8b561195935592bb9979996a27
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
2017-05-22 13:29:16 +05:30
Greg Kroah-Hartman
b2fc10e724 This is the 4.4.69 stable release
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Merge 4.4.69 into android-4.4

Changes in 4.4.69
	xen: adjust early dom0 p2m handling to xen hypervisor behavior
	target: Fix compare_and_write_callback handling for non GOOD status
	target/fileio: Fix zero-length READ and WRITE handling
	target: Convert ACL change queue_depth se_session reference usage
	iscsi-target: Set session_fall_back_to_erl0 when forcing reinstatement
	usb: host: xhci: print correct command ring address
	USB: serial: ftdi_sio: add device ID for Microsemi/Arrow SF2PLUS Dev Kit
	USB: Proper handling of Race Condition when two USB class drivers try to call init_usb_class simultaneously
	staging: vt6656: use off stack for in buffer USB transfers.
	staging: vt6656: use off stack for out buffer USB transfers.
	staging: gdm724x: gdm_mux: fix use-after-free on module unload
	staging: comedi: jr3_pci: fix possible null pointer dereference
	staging: comedi: jr3_pci: cope with jiffies wraparound
	usb: misc: add missing continue in switch
	usb: Make sure usb/phy/of gets built-in
	usb: hub: Fix error loop seen after hub communication errors
	usb: hub: Do not attempt to autosuspend disconnected devices
	x86/boot: Fix BSS corruption/overwrite bug in early x86 kernel startup
	selftests/x86/ldt_gdt_32: Work around a glibc sigaction() bug
	x86, pmem: Fix cache flushing for iovec write < 8 bytes
	um: Fix PTRACE_POKEUSER on x86_64
	KVM: x86: fix user triggerable warning in kvm_apic_accept_events()
	KVM: arm/arm64: fix races in kvm_psci_vcpu_on
	block: fix blk_integrity_register to use template's interval_exp if not 0
	crypto: algif_aead - Require setkey before accept(2)
	dm era: save spacemap metadata root after the pre-commit
	vfio/type1: Remove locked page accounting workqueue
	IB/core: Fix sysfs registration error flow
	IB/IPoIB: ibX: failed to create mcg debug file
	IB/mlx4: Fix ib device initialization error flow
	IB/mlx4: Reduce SRIOV multicast cleanup warning message to debug level
	ext4: evict inline data when writing to memory map
	fs/xattr.c: zero out memory copied to userspace in getxattr
	ceph: fix memory leak in __ceph_setxattr()
	fs/block_dev: always invalidate cleancache in invalidate_bdev()
	Set unicode flag on cifs echo request to avoid Mac error
	SMB3: Work around mount failure when using SMB3 dialect to Macs
	CIFS: fix mapping of SFM_SPACE and SFM_PERIOD
	cifs: fix CIFS_IOC_GET_MNT_INFO oops
	CIFS: add misssing SFM mapping for doublequote
	padata: free correct variable
	arm64: KVM: Fix decoding of Rt/Rt2 when trapping AArch32 CP accesses
	serial: samsung: Use right device for DMA-mapping calls
	serial: omap: fix runtime-pm handling on unbind
	serial: omap: suspend device on probe errors
	tty: pty: Fix ldisc flush after userspace become aware of the data already
	Bluetooth: Fix user channel for 32bit userspace on 64bit kernel
	Bluetooth: hci_bcm: add missing tty-device sanity check
	Bluetooth: hci_intel: add missing tty-device sanity check
	mac80211: pass RX aggregation window size to driver
	mac80211: pass block ack session timeout to to driver
	mac80211: RX BA support for sta max_rx_aggregation_subframes
	wlcore: Pass win_size taken from ieee80211_sta to FW
	wlcore: Add RX_BA_WIN_SIZE_CHANGE_EVENT event
	ipmi: Fix kernel panic at ipmi_ssif_thread()
	Linux 4.4.69

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2017-05-21 19:01:22 +02:00
Jason A. Donenfeld
f08bc4d633 padata: free correct variable
commit 07a77929ba672d93642a56dc2255dd21e6e2290b upstream.

The author meant to free the variable that was just allocated, instead
of the one that failed to be allocated, but made a simple typo. This
patch rectifies that.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-20 14:27:02 +02:00
Syed Rameez Mustafa
5b138bd514 sched: Fix load tracking bug to avoid adding phantom task demand
When update_task_ravg() is called with the TASK_UPDATE event on a task
that is not on the runqueue, task demand accounting incorrectly treats
the time delta as execution time. This can happen when a sleeping
task is moved to/from colocation groups. This phantom execution time can
cause unpredictable changes to demand that in turn can result in
incorrect task placement. Fix the issue by adding special handling of
TASK_UPDATE in task demand accounting. CPU busy time accounting already
has all the necessary checks.

Change-Id: Ibb42d83ac353bf2e849055fa3cb5c22e7acd56de
Signed-off-by: Syed Rameez Mustafa <rameezmustafa@codeaurora.org>
2017-05-19 12:30:51 -07:00
Kees Cook
be814112fd time: Remove CONFIG_TIMER_STATS
Currently CONFIG_TIMER_STATS exposes process information across namespaces:

kernel/time/timer_list.c print_timer():

        SEQ_printf(m, ", %s/%d", tmp, timer->start_pid);

/proc/timer_list:

 #11: <0000000000000000>, hrtimer_wakeup, S:01, do_nanosleep, cron/2570

Given that the tracer can give the same information, this patch entirely
removes CONFIG_TIMER_STATS.

Change-Id: I66e06ae2d6e32c309824310d3d9bf54d1047eab1
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: John Stultz <john.stultz@linaro.org>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: linux-doc@vger.kernel.org
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Xing Gao <xgao01@email.wm.edu>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Jessica Frazelle <me@jessfraz.com>
Cc: kernel-hardening@lists.openwall.com
Cc: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Michal Marek <mmarek@suse.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Olof Johansson <olof@lixom.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-api@vger.kernel.org
Cc: Arjan van de Ven <arjan@linux.intel.com>
Link: http://lkml.kernel.org/r/20170208192659.GA32582@beast
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Git-commit: dfb4357da6ddbdf57d583ba64361c9d792b0e0b1
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
[ohaugan@codeaurora.org: Fixed merge conflicts]
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2017-05-16 14:16:43 -07:00
Linux Build Service Account
df5db93178 Merge "tracing: do not leak kernel addresses" 2017-05-16 06:49:32 -07:00
Nick Desaulniers
ccc9ce7791 tracing: do not leak kernel addresses
This likely breaks tracing tools like trace-cmd.  It logs in the same
format but now addresses are all 0x0.

Bug: 34277115
Change-Id: Ifb0d4d2a184bf0d95726de05b1acee0287a375d9
Git-repo: https://android.googlesource.com/kernel/msm
Git-commit: 9ad8f2cc1bb73a3e2255dff4ee9c45c909869225
Signed-off-by: Dennis Cagle <d-cagle@codeaurora.org>
2017-05-15 10:45:17 -07:00
Neeraj Upadhyay
1ef28deec0 timer: Clear deferrable_pending while handling timer softirq
Clear deferrable_pending everytime timer softirq is run.
This handles a potential race condition, where one CPU
handles all deferrable timers, before the other CPU gets
a change to run timer softirq. Due to the deferrable_pending
not getting cleared, subsequently, CPUs do not raise
the softirq for handling expired deferrable timers,
in nohz idle enter path.

Change-Id: Ie5fd78f9b27e7553ba43101b86ad939c289827e0
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
2017-05-15 00:06:22 -07:00
Syed Rameez Mustafa
64510d4751 sched: Don't active migrate tasks to CPUs in the same cluster
At the tick the scheduler checks whether a running task needs to
be migrated for some reason. If the reason is to up or down migrate
a task, we should only kick active balance when select_best_cpu()
returns a CPU in the appropriate cluster. Active migrating a task
to another CPU in the same cluster is wasteful.

Change-Id: I2c899a9c2dfb8ec4f983d7e355f0960f88bd3b45
Signed-off-by: Syed Rameez Mustafa <rameezmustafa@codeaurora.org>
2017-05-09 14:18:08 -07:00
Linux Build Service Account
7d2dbd9538 Merge "Merge branch 'android-4.4@e4528dd' into branch 'msm-4.4'" 2017-05-03 23:31:48 -07:00
Linux Build Service Account
3939f41b22 Merge "Merge remote-tracking branch 'remotes/quic/dev/msm-4.4-8996au' into msm-4.4" 2017-05-02 09:07:39 -07:00
Blagovest Kolenichev
95a027ead7 Merge branch 'android-4.4@e4528dd' into branch 'msm-4.4'
* refs/heads/tmp-e4528dd:
  Linux 4.4.65
  perf/core: Fix concurrent sys_perf_event_open() vs. 'move_group' race
  ping: implement proper locking
  staging/android/ion : fix a race condition in the ion driver
  vfio/pci: Fix integer overflows, bitmask check
  tipc: check minimum bearer MTU
  netfilter: nfnetlink: correctly validate length of batch messages
  xc2028: avoid use after free
  mnt: Add a per mount namespace limit on the number of mounts
  tipc: fix socket timer deadlock
  tipc: fix random link resets while adding a second bearer
  gfs2: avoid uninitialized variable warning
  hostap: avoid uninitialized variable use in hfa384x_get_rid
  tty: nozomi: avoid a harmless gcc warning
  tipc: correct error in node fsm
  tipc: re-enable compensation for socket receive buffer double counting
  tipc: make dist queue pernet
  tipc: make sure IPv6 header fits in skb headroom
  ANDROID: uid_sys_stats: fix access of task_uid(task)
  BACKPORT: f2fs: sanity check log_blocks_per_seg
  Linux 4.4.64
  tipc: fix crash during node removal
  block: fix del_gendisk() vs blkdev_ioctl crash
  x86, pmem: fix broken __copy_user_nocache cache-bypass assumptions
  hv: don't reset hv_context.tsc_page on crash
  Drivers: hv: balloon: account for gaps in hot add regions
  Drivers: hv: balloon: keep track of where ha_region starts
  Tools: hv: kvp: ensure kvp device fd is closed on exec
  kvm: arm/arm64: Fix locking for kvm_free_stage2_pgd
  x86/mce/AMD: Give a name to MCA bank 3 when accessed with legacy MSRs
  powerpc/kprobe: Fix oops when kprobed on 'stdu' instruction
  ubi/upd: Always flush after prepared for an update
  mac80211: reject ToDS broadcast data frames
  mmc: sdhci-esdhc-imx: increase the pad I/O drive strength for DDR50 card
  ACPI / power: Avoid maybe-uninitialized warning
  Input: elantech - add Fujitsu Lifebook E547 to force crc_enabled
  VSOCK: Detach QP check should filter out non matching QPs.
  Drivers: hv: vmbus: Reduce the delay between retries in vmbus_post_msg()
  Drivers: hv: get rid of timeout in vmbus_open()
  Drivers: hv: don't leak memory in vmbus_establish_gpadl()
  s390/mm: fix CMMA vs KSM vs others
  CIFS: remove bad_network_name flag
  cifs: Do not send echoes before Negotiate is complete
  ring-buffer: Have ring_buffer_iter_empty() return true when empty
  tracing: Allocate the snapshot buffer before enabling probe
  KEYS: fix keyctl_set_reqkey_keyring() to not leak thread keyrings
  KEYS: Change the name of the dead type to ".dead" to prevent user access
  KEYS: Disallow keyrings beginning with '.' to be joined as session keyrings
  ANDROID: sdcardfs: Call lower fs's revalidate
  ANDROID: sdcardfs: Avoid setting GIDs outside of valid ranges
  ANDROID: sdcardfs: Copy meta-data from lower inode
  Revert "Revert "Android: sdcardfs: Don't do d_add for lower fs""
  ANDROID: sdcardfs: Use filesystem specific hash
  ANDROID: AVB error handler to invalidate vbmeta partition.
  ANDROID: Update init/do_mounts_dm.c to the latest ChromiumOS version.
  Revert "[RFC]cgroup: Change from CAP_SYS_NICE to CAP_SYS_RESOURCE for cgroup migration permissions"

Conflicts:
	drivers/md/Makefile

Change-Id: I8f5ed53cb8b6cc66914f10c6ac820003b87b8759
Signed-off-by: Blagovest Kolenichev <bkolenichev@codeaurora.org>
2017-05-02 06:40:36 -07:00
Zhiqiang Tu
b15484bc06 Merge remote-tracking branch 'remotes/quic/dev/msm-4.4-8996au' into msm-4.4
Conflicts:
	arch/arm/boot/dts/qcom/msm8996-auto-cdp.dtsi
	drivers/gpu/drm/msm/Makefile

Change-Id: Ief80c28ff1422fd71a0c3d2041531e2ab078ee7a
Signed-off-by: Zhiqiang Tu <ztu@codeaurora.org>
2017-05-02 08:59:16 +08:00
Greg Kroah-Hartman
e4528dd775 This is the 4.4.65 stable release
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Merge 4.4.65 into android-4.4

Changes in 4.4.65:
	tipc: make sure IPv6 header fits in skb headroom
	tipc: make dist queue pernet
	tipc: re-enable compensation for socket receive buffer double counting
	tipc: correct error in node fsm
	tty: nozomi: avoid a harmless gcc warning
	hostap: avoid uninitialized variable use in hfa384x_get_rid
	gfs2: avoid uninitialized variable warning
	tipc: fix random link resets while adding a second bearer
	tipc: fix socket timer deadlock
	mnt: Add a per mount namespace limit on the number of mounts
	xc2028: avoid use after free
	netfilter: nfnetlink: correctly validate length of batch messages
	tipc: check minimum bearer MTU
	vfio/pci: Fix integer overflows, bitmask check
	staging/android/ion : fix a race condition in the ion driver
	ping: implement proper locking
	perf/core: Fix concurrent sys_perf_event_open() vs. 'move_group' race
	Linux 4.4.65

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2017-04-30 07:30:52 +02:00
Peter Zijlstra
416bd4a366 perf/core: Fix concurrent sys_perf_event_open() vs. 'move_group' race
commit 321027c1fe77f892f4ea07846aeae08cefbbb290 upstream.

Di Shen reported a race between two concurrent sys_perf_event_open()
calls where both try and move the same pre-existing software group
into a hardware context.

The problem is exactly that described in commit:

  f63a8daa58 ("perf: Fix event->ctx locking")

... where, while we wait for a ctx->mutex acquisition, the event->ctx
relation can have changed under us.

That very same commit failed to recognise sys_perf_event_context() as an
external access vector to the events and thereby didn't apply the
established locking rules correctly.

So while one sys_perf_event_open() call is stuck waiting on
mutex_lock_double(), the other (which owns said locks) moves the group
about. So by the time the former sys_perf_event_open() acquires the
locks, the context we've acquired is stale (and possibly dead).

Apply the established locking rules as per perf_event_ctx_lock_nested()
to the mutex_lock_double() for the 'move_group' case. This obviously means
we need to validate state after we acquire the locks.

Reported-by: Di Shen (Keen Lab)
Tested-by: John Dias <joaodias@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Min Chong <mchong@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: f63a8daa58 ("perf: Fix event->ctx locking")
Link: http://lkml.kernel.org/r/20170106131444.GZ3174@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
[bwh: Backported to 4.4:
 - Test perf_event::group_flags instead of group_caps
 - Adjust context]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-30 05:49:29 +02:00