linux-stable.git/kernel/sched_rt.c, branch master Linux kernel stable tree sched: Move all scheduler bits into kernel/sched/ 2011-11-17T11:20:22+00:00 Peter Zijlstra a.p.zijlstra@chello.nl 2011-11-15T16:14:39+00:00 391e43da797a96aeb65410281891f6d0b0e9611c There's too many sched*.[ch] files in kernel/, give them their own directory. (No code changed, other than Makefile glue added.) Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu> 
There's too many sched*.[ch] files in kernel/, give them their own
directory.

(No code changed, other than Makefile glue added.)

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
sched: Make separate sched*.c translation units 2011-11-17T11:20:19+00:00 Peter Zijlstra a.p.zijlstra@chello.nl 2011-10-25T08:00:11+00:00 029632fbb7b7c9d85063cc9eb470de6c54873df3 Since once needs to do something at conferences and fixing compile warnings doesn't actually require much if any attention I decided to break up the sched.c #include "*.c" fest. This further modularizes the scheduler code. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/n/tip-x0fcd3mnp8f9c99grcpewmhi@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu> 
Since once needs to do something at conferences and fixing compile
warnings doesn't actually require much if any attention I decided
to break up the sched.c #include "*.c" fest.

This further modularizes the scheduler code.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-x0fcd3mnp8f9c99grcpewmhi@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
sched: Fix comment for requeue_rt_entity 2011-11-16T07:48:27+00:00 Richard Weinberger richard@nod.at 2011-11-12T17:07:57+00:00 60686317da05049385eae86e44c710cde535f95f Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1321117677-3282-1-git-send-email-richard@nod.at Signed-off-by: Ingo Molnar <mingo@elte.hu> 
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1321117677-3282-1-git-send-email-richard@nod.at
Signed-off-by: Ingo Molnar <mingo@elte.hu>
sched, rt: Provide means of disabling cross-cpu bandwidth sharing 2011-11-14T11:50:40+00:00 Peter Zijlstra a.p.zijlstra@chello.nl 2011-10-06T20:39:14+00:00 4a6184ce7a48c478dee0d8a9ed74c1fa35161858 Normally the RT bandwidth scheme will share bandwidth across the entire root_domain. However sometimes its convenient to disable this sharing for debug purposes. Provide a simple feature switch to this end. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu> 
Normally the RT bandwidth scheme will share bandwidth across the
entire root_domain. However sometimes its convenient to disable this
sharing for debug purposes. Provide a simple feature switch to this
end.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
sched: Warn on rt throttling 2011-10-06T10:47:04+00:00 Thomas Gleixner tglx@linutronix.de 2011-10-05T11:32:34+00:00 1c83437e80186832a9a48dbb6b8868d28e40e562 The default rt-throttling is a source of never ending questions. Warn once when we go into throttling so folks have that info in dmesg. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1110051331480.18778@ionos Signed-off-by: Ingo Molnar <mingo@elte.hu> 
The default rt-throttling is a source of never ending questions. Warn
once when we go into throttling so folks have that info in dmesg.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1110051331480.18778@ionos
Signed-off-by: Ingo Molnar <mingo@elte.hu>
sched: Unify the ->cpus_allowed mask copy 2011-10-06T10:47:00+00:00 Peter Zijlstra peterz@infradead.org 2011-06-25T13:45:46+00:00 4939602a2441306008c6dca38216b741d4e09a42 Currently every sched_class::set_cpus_allowed() implementation has to copy the cpumask into task_struct::cpus_allowed, this is pointless, put this copy in the generic code. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/n/tip-jhl5s9fckd9ptw1fzbqqlrd3@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu> 
Currently every sched_class::set_cpus_allowed() implementation has to
copy the cpumask into task_struct::cpus_allowed, this is pointless,
put this copy in the generic code.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/n/tip-jhl5s9fckd9ptw1fzbqqlrd3@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
sched: Wrap scheduler p->cpus_allowed access 2011-10-06T10:46:56+00:00 Peter Zijlstra peterz@infradead.org 2011-06-16T10:23:22+00:00 fa17b507f142d37aeac322a95f6f7c6375f25601 This task is preparatory for the migrate_disable() implementation, but stands on its own and provides a cleanup. It currently only converts those sites required for task-placement. Kosaki-san once mentioned replacing cpus_allowed with a proper cpumask_t instead of the NR_CPUS sized array it currently is, that would also require something like this. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Link: http://lkml.kernel.org/n/tip-e42skvaddos99psip0vce41o@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu> 
This task is preparatory for the migrate_disable() implementation, but
stands on its own and provides a cleanup.

It currently only converts those sites required for task-placement.
Kosaki-san once mentioned replacing cpus_allowed with a proper
cpumask_t instead of the NR_CPUS sized array it currently is, that
would also require something like this.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Link: http://lkml.kernel.org/n/tip-e42skvaddos99psip0vce41o@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Merge branch 'linus' into sched/core 2011-10-04T09:09:08+00:00 Ingo Molnar mingo@elte.hu 2011-10-04T09:08:16+00:00 22f92bacbeea24b20e447444c28e7cad9f1ac3f8 Merge reason: pick up the latest fixes. Signed-off-by: Ingo Molnar <mingo@elte.hu> 
Merge reason: pick up the latest fixes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
sched/rt: Migrate equal priority tasks to available CPUs 2011-09-18T11:48:56+00:00 Shawn Bohrer sbohrer@rgmadvisors.com 2011-09-12T14:28:04+00:00 3be209a8e22cedafc1b6945608b7bb8d9887ab61 Commit 43fa5460fe60dea5c610490a1d263415419c60f6 ("sched: Try not to migrate higher priority RT tasks") also introduced a change in behavior which keeps RT tasks on the same CPU if there is an equal priority RT task currently running even if there are empty CPUs available. This can cause unnecessary wakeup latencies, and can prevent the scheduler from balancing all RT tasks across available CPUs. This change causes an RT task to search for a new CPU if an equal priority RT task is already running on wakeup. Lower priority tasks will still have to wait on higher priority tasks, but the system should still balance out because there is always the possibility that if there are both a high and low priority RT tasks on a given CPU that the high priority task could wakeup while the low priority task is running and force it to search for a better runqueue. Signed-off-by: Shawn Bohrer <sbohrer@rgmadvisors.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Tested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: stable@kernel.org # 37+ Link: http://lkml.kernel.org/r/1315837684-18733-1-git-send-email-sbohrer@rgmadvisors.com Signed-off-by: Ingo Molnar <mingo@elte.hu> 
Commit 43fa5460fe60dea5c610490a1d263415419c60f6 ("sched: Try not to
migrate higher priority RT tasks") also introduced a change in behavior
which keeps RT tasks on the same CPU if there is an equal priority RT
task currently running even if there are empty CPUs available.

This can cause unnecessary wakeup latencies, and can prevent the
scheduler from balancing all RT tasks across available CPUs.

This change causes an RT task to search for a new CPU if an equal
priority RT task is already running on wakeup.  Lower priority tasks
will still have to wait on higher priority tasks, but the system should
still balance out because there is always the possibility that if there
are both a high and low priority RT tasks on a given CPU that the high
priority task could wakeup while the low priority task is running and
force it to search for a better runqueue.

Signed-off-by: Shawn Bohrer <sbohrer@rgmadvisors.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Tested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: stable@kernel.org # 37+
Link: http://lkml.kernel.org/r/1315837684-18733-1-git-send-email-sbohrer@rgmadvisors.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
sched: Implement hierarchical task accounting for SCHED_OTHER 2011-08-14T10:01:13+00:00 Paul Turner pjt@google.com 2011-07-21T16:43:27+00:00 953bfcd10e6f3697233e8e5128c611d275da39c1 Introduce hierarchical task accounting for the group scheduling case in CFS, as well as promoting the responsibility for maintaining rq->nr_running to the scheduling classes. The primary motivation for this is that with scheduling classes supporting bandwidth throttling it is possible for entities participating in throttled sub-trees to not have root visible changes in rq->nr_running across activate and de-activate operations. This in turn leads to incorrect idle and weight-per-task load balance decisions. This also allows us to make a small fixlet to the fastpath in pick_next_task() under group scheduling. Note: this issue also exists with the existing sched_rt throttling mechanism. This patch does not address that. Signed-off-by: Paul Turner <pjt@google.com> Reviewed-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20110721184756.878333391@google.com Signed-off-by: Ingo Molnar <mingo@elte.hu> 
Introduce hierarchical task accounting for the group scheduling case in CFS, as
well as promoting the responsibility for maintaining rq->nr_running to the
scheduling classes.

The primary motivation for this is that with scheduling classes supporting
bandwidth throttling it is possible for entities participating in throttled
sub-trees to not have root visible changes in rq->nr_running across activate
and de-activate operations.  This in turn leads to incorrect idle and
weight-per-task load balance decisions.

This also allows us to make a small fixlet to the fastpath in pick_next_task()
under group scheduling.

Note: this issue also exists with the existing sched_rt throttling mechanism.
This patch does not address that.

Signed-off-by: Paul Turner <pjt@google.com>
Reviewed-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110721184756.878333391@google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>