Commit 12695578 authored Jul 15, 2015 by Yuyang Du Committed by Ingo Molnar Aug 03, 2015

sched/fair: Remove task and group entity load when they are dead



When task exits or group is destroyed, the entity's load should be
removed from its parent cfs_rq's load. Otherwise, it will take time
for the parent cfs_rq to decay the dead entity's load to 0, which
is not desired.

Signed-off-by: Yuyang Du <yuyang.du@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: arjan@linux.intel.com
Cc: bsegall@google.com
Cc: dietmar.eggemann@arm.com
Cc: fengguang.wu@intel.com
Cc: len.brown@intel.com
Cc: morten.rasmussen@arm.com
Cc: pjt@google.com
Cc: rafael.j.wysocki@intel.com
Cc: umgwanakikbuti@gmail.com
Cc: vincent.guittot@linaro.org
Link: http://lkml.kernel.org/r/1436918682-4971-6-git-send-email-yuyang.du@intel.com


Signed-off-by: Ingo Molnar <mingo@kernel.org>

parent 540247fb

kernel/sched/fair.c

+10 −1

Original line number	Diff line number	Diff line
		@@ -4913,6 +4913,11 @@ static void migrate_task_rq_fair(struct task_struct *p, int next_cpu)
		/* We have migrated, no longer consider this task hot */
		p->se.exec_start = 0;
		}

		static void task_dead_fair(struct task_struct *p)
		{
		remove_entity_load_avg(&p->se);
		}
		#endif /* CONFIG_SMP */

		static unsigned long
		@@ -7991,9 +7996,12 @@ void free_fair_sched_group(struct task_group *tg)
		for_each_possible_cpu(i) {
		if (tg->cfs_rq)
		kfree(tg->cfs_rq[i]);
		if (tg->se)
		if (tg->se) {
		if (tg->se[i])
		remove_entity_load_avg(tg->se[i]);
		kfree(tg->se[i]);
		}
		}

		kfree(tg->cfs_rq);
		kfree(tg->se);
		@@ -8179,6 +8187,7 @@ const struct sched_class fair_sched_class = {
		.rq_offline = rq_offline_fair,

		.task_waking = task_waking_fair,
		.task_dead = task_dead_fair,
		#endif

		.set_curr_task = set_curr_task_fair,