diff options
| author | Steve Muckle <smuckle@codeaurora.org> | 2013-03-11 16:33:42 -0700 |
|---|---|---|
| committer | Moyster <oysterized@gmail.com> | 2016-09-18 19:40:13 +0200 |
| commit | f8ee38a456756fd5caed57434f30b9e622482104 (patch) | |
| tree | 3dea3950a60597a96265a3b691dd65a31cc4e79f /kernel/sched | |
| parent | 9f1f7e74e397ea5f3d9325ef269d31e99f7322e9 (diff) | |
sched: provide per cpu-cgroup option to notify on migrations
On systems where CPUs may run asynchronously, task migrations
between CPUs running at grossly different speeds can cause
problems.
This change provides a mechanism to notify a subsystem
in the kernel if a task in a particular cgroup migrates to a
different CPU. Other subsystems (such as cpufreq) may then
register for this notifier to take appropriate action when
such a task is migrated.
The cgroup attribute to set for this behavior is
"notify_on_migrate" .
Change-Id: Ie1868249e53ef901b89c837fdc33b0ad0c0a4590
Signed-off-by: Steve Muckle <smuckle@codeaurora.org>
Signed-off-by: W4TCH0UT <ateekujjawal@gmail.com>
Conflicts:
kernel/sched/core.c
kernel/sched/rt.c
Diffstat (limited to 'kernel/sched')
| -rw-r--r-- | kernel/sched/rt.c | 20 |
1 files changed, 19 insertions, 1 deletions
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 692fb1e77..c1b6096fc 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -2401,6 +2401,7 @@ static int push_rt_task(struct rq *rq) struct task_struct *next_task; struct rq *lowest_rq; int ret = 0; + bool moved = false; if (!rq->rt.overloaded) return 0; @@ -2465,6 +2466,7 @@ retry: deactivate_task(rq, next_task, 0); set_task_cpu(next_task, lowest_rq->cpu); + moved = true; activate_task(lowest_rq, next_task, 0); ret = 1; @@ -2475,6 +2477,11 @@ retry: out: put_task_struct(next_task); + if (moved && task_notify_on_migrate(next_task)) + atomic_notifier_call_chain(&migration_notifier_head, + cpu_of(lowest_rq), + (void *)cpu_of(rq)); + return ret; } @@ -2614,9 +2621,11 @@ static int pull_rt_task(struct rq *this_rq) int ret = 0; #ifndef CONFIG_MT_RT_SCHED int cpu; - struct task_struct *p; + struct task_struct *p = NULL; struct rq *src_rq; #endif + bool moved = false; + int src_cpu = 0; mt_sched_printf(sched_rt_info, "0. pull_rt_task %d %d ", rt_overloaded(this_rq), this_rq->cpu); @@ -2689,6 +2698,10 @@ static int pull_rt_task(struct rq *this_rq) deactivate_task(src_rq, p, 0); set_task_cpu(p, this_cpu); activate_task(this_rq, p, 0); + + moved = true; + src_cpu = cpu_of(src_rq); + /* * We continue with the search, just in * case there's an even higher prio task @@ -2701,6 +2714,11 @@ skip: } #endif + if (moved && task_notify_on_migrate(p)) + atomic_notifier_call_chain(&migration_notifier_head, + this_cpu, + (void *)src_cpu); + return ret; } |