diff options
| author | Andy Lutomirski <luto@amacapital.net> | 2014-06-04 10:31:17 -0700 |
|---|---|---|
| committer | Alex Shi <alex.shi@linaro.org> | 2014-12-03 14:51:48 +0800 |
| commit | 95ec016860904331c594cdfde6385816feb1e16a (patch) | |
| tree | 5f489b0ad0bc923b5d51206943bfd7311746b519 | |
| parent | 86c002558e55a9eb1465c5fe20c041561aa185d4 (diff) | |
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>
(cherry picked from commit 67b9ca70c3030e832999e8d1cdba2984c7bb5bfc)
Signed-off-by: Alex Shi <alex.shi@linaro.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 588c4cc2cdb..bbaf6e5d1d0 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -626,26 +626,7 @@ 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); |