From 78b6b15770618efb60d84e2d605f6b93dc94051b Mon Sep 17 00:00:00 2001 From: Chengming Zhou Date: Thu, 18 Aug 2022 20:47:57 +0800 Subject: sched/fair: Maintain task se depth in set_task_rq() Previously we only maintain task se depth in task_move_group_fair(), if a !fair task change task group, its se depth will not be updated, so commit eb7a59b2c888 ("sched/fair: Reset se-depth when task switched to FAIR") fix the problem by updating se depth in switched_to_fair() too. Then commit daa59407b558 ("sched/fair: Unify switched_{from,to}_fair() and task_move_group_fair()") unified these two functions, moved se.depth setting to attach_task_cfs_rq(), which further into attach_entity_cfs_rq() with commit df217913e72e ("sched/fair: Factorize attach/detach entity"). This patch move task se depth maintenance from attach_entity_cfs_rq() to set_task_rq(), which will be called when CPU/cgroup change, so its depth will always be correct. This patch is preparation for the next patch. Signed-off-by: Chengming Zhou Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Dietmar Eggemann Reviewed-by: Vincent Guittot Link: https://lore.kernel.org/r/20220818124805.601-2-zhouchengming@bytedance.com --- kernel/sched/fair.c | 8 -------- kernel/sched/sched.h | 1 + 2 files changed, 1 insertion(+), 8 deletions(-) (limited to 'kernel/sched') diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index da388657d5ac..a3b0f8b1029e 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -11562,14 +11562,6 @@ static void attach_entity_cfs_rq(struct sched_entity *se) { struct cfs_rq *cfs_rq = cfs_rq_of(se); -#ifdef CONFIG_FAIR_GROUP_SCHED - /* - * Since the real-depth could have been changed (only FAIR - * class maintain depth value), reset depth properly. - */ - se->depth = se->parent ? se->parent->depth + 1 : 0; -#endif - /* Synchronize entity with its cfs_rq */ update_load_avg(cfs_rq, se, sched_feat(ATTACH_AGE_LOAD) ? 0 : SKIP_AGE_LOAD); attach_entity_load_avg(cfs_rq, se); diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 3ccd35c22f0f..4c4822141026 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -1930,6 +1930,7 @@ static inline void set_task_rq(struct task_struct *p, unsigned int cpu) set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]); p->se.cfs_rq = tg->cfs_rq[cpu]; p->se.parent = tg->se[cpu]; + p->se.depth = tg->se[cpu] ? tg->se[cpu]->depth + 1 : 0; #endif #ifdef CONFIG_RT_GROUP_SCHED -- cgit v1.2.3