Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit f07ab013 authored Feb 19, 2018 by Pavankumar Kondeti

sched/fair: Add EAS_USE_NEED_IDLE feature



The schedtune.prefer_idle flag makes scheduler to look for an idle
CPU across all clusters. Where as the need_idle flag limits the
search to the lower capacity cluster which strikes a better
balance between power and performance compared to prefer_idle.

Add EAS_USE_NEED_IDLE feature, when enabled need_idle path is
enforced for tasks that has schedtune.prefer_idle set.

Change-Id: Ic83cd9f8bae1112efa4e62de3c60a86ba9c777d7
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>

parent ec7e154d

kernel/sched/fair.c

+6 −1

Original line number	Diff line number	Diff line
		@@ -7251,7 +7251,12 @@ static int select_energy_cpu_brute(struct task_struct *p, int prev_cpu, int sync
		#endif

		fbt_env.rtg_target = rtg_target;
		if (sched_feat(EAS_USE_NEED_IDLE) && prefer_idle) {
		fbt_env.need_idle = true;
		prefer_idle = false;
		} else {
		fbt_env.need_idle = wake_to_idle(p);
		}
		fbt_env.placement_boost = task_sched_boost(p) ?
		sched_boost_policy() != SCHED_BOOST_NONE :
		false;

kernel/sched/features.h

+6 −0

Original line number	Diff line number	Diff line
		@@ -98,3 +98,9 @@ SCHED_FEAT(MIN_CAPACITY_CAPPING, false)
		* OFF: Use whichever of target or backup saves most.
		*/
		SCHED_FEAT(FBT_STRICT_ORDER, false)
		/*
		* Enforce schedtune.prefer_idle to take need_idle path.
		* ON: schedtune.prefer_idle is replaced with need_idle
		* OFF: schedtune.prefer_idle is honored as is.
		*/
		SCHED_FEAT(EAS_USE_NEED_IDLE, true)