From 1269557889b477e3e43ab99a21035ddf8f7cea4d Mon Sep 17 00:00:00 2001 From: Yuyang Du Date: Wed, 15 Jul 2015 08:04:40 +0800 Subject: [PATCH] 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 Signed-off-by: Peter Zijlstra (Intel) Cc: Linus Torvalds Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Thomas Gleixner 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 --- kernel/sched/fair.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index f636db0e086c..5532bf38e844 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -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 @@ -7991,8 +7996,11 @@ 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); @@ -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,