diff options
author | Andy Lutomirski <luto@amacapital.net> | 2014-06-04 19:31:17 +0200 |
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committer | Ingo Molnar <mingo@kernel.org> | 2014-06-05 12:09:52 +0200 |
commit | 67b9ca70c3030e832999e8d1cdba2984c7bb5bfc (patch) | |
tree | c7a2d408297c74954e284895cf4ae74172c9747b | |
parent | sched/idle: Clear polling before descheduling the idle thread (diff) | |
download | linux-67b9ca70c3030e832999e8d1cdba2984c7bb5bfc.tar.xz linux-67b9ca70c3030e832999e8d1cdba2984c7bb5bfc.zip |
sched/idle: Simplify wake_up_idle_cpu()
Now that rq->idle's polling bit is a reliable indication that the cpu is
polling, use it.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: nicolas.pitre@linaro.org
Cc: daniel.lezcano@linaro.org
Cc: umgwanakikbuti@gmail.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/922f00761445a830ebb23d058e2ae53956ce2d73.1401902905.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-rw-r--r-- | kernel/sched/core.c | 21 |
1 files changed, 1 insertions, 20 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index e4c0ddd3db8e..6afbfeefddd6 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -628,26 +628,7 @@ static void wake_up_idle_cpu(int cpu) if (cpu == smp_processor_id()) return; - /* - * This is safe, as this function is called with the timer - * wheel base lock of (cpu) held. When the CPU is on the way - * to idle and has not yet set rq->curr to idle then it will - * be serialized on the timer wheel base lock and take the new - * timer into account automatically. - */ - if (rq->curr != rq->idle) - return; - - /* - * We can set TIF_RESCHED on the idle task of the other CPU - * lockless. The worst case is that the other CPU runs the - * idle task through an additional NOOP schedule() - */ - set_tsk_need_resched(rq->idle); - - /* NEED_RESCHED must be visible before we test polling */ - smp_mb(); - if (!tsk_is_polling(rq->idle)) + if (set_nr_and_not_polling(rq->idle)) smp_send_reschedule(cpu); else trace_sched_wake_idle_without_ipi(cpu); |