Commit cd76b215 authored Mar 07, 2017 by Joonwoo Park Committed by Todd Kjos Nov 14, 2017

sched: EAS: kill incorrect nohz idle cpu kick



EAS won't allow NOHZ idle balancer until CPU's over utilized.  However
nohz_kick_needed() can return true.  This causes idle CPU wake up for
nothing.

Change-Id: I6e548442e29e4f85cda695e4c7101dd591b12fe6
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
(cherry picked from commit 3989a247e2744f437233a36a0183edf3b3dfc8f1)
[trivial cherry-pick issues]
Signed-off-by: Quentin Perret <quentin.perret@arm.com>

parent d7a6b8be

kernel/sched/fair.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -10145,12 +10145,12 @@ static inline bool nohz_kick_needed(struct rq *rq)
		return true;

		/* Do idle load balance if there have misfit task */
		if (energy_aware() && rq->misfit_task)
		return true;
		if (energy_aware())
		return rq->misfit_task;

		rcu_read_lock();
		sds = rcu_dereference(per_cpu(sd_llc_shared, cpu));
		if (sds && !energy_aware()) {
		if (sds) {
		/*
		* XXX: write a coherent comment on why we do this.
		* See also: http://lkml.kernel.org/r/20111202010832.602203411@sbsiddha-desk.sc.intel.com