From 3e386d56bafbb6d2540b49367444997fc671ea69 Mon Sep 17 00:00:00 2001 From: Yuyang Du Date: Tue, 13 Oct 2015 09:18:23 +0800 Subject: [PATCH] sched/fair: Update task group's load_avg after task migration When cfs_rq has cfs_rq->removed_load_avg set (when a task migrates from this cfs_rq), we need to update its contribution to the group's load_avg. This should not increase tg's update too much, because in most cases, the cfs_rq has already decayed its load_avg. Tested-by: Dietmar Eggemann Signed-off-by: Yuyang Du Signed-off-by: Peter Zijlstra (Intel) Acked-by: Dietmar Eggemann Cc: Linus Torvalds Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1444699103-20272-2-git-send-email-yuyang.du@intel.com Signed-off-by: Ingo Molnar --- kernel/sched/fair.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index bc62c5096e54..9a5e60fe721a 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -2664,13 +2664,14 @@ static inline u64 cfs_rq_clock_task(struct cfs_rq *cfs_rq); /* Group cfs_rq's load_avg is used for task_h_load and update_cfs_share */ static inline int update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq) { - int decayed; struct sched_avg *sa = &cfs_rq->avg; + int decayed, removed = 0; if (atomic_long_read(&cfs_rq->removed_load_avg)) { long r = atomic_long_xchg(&cfs_rq->removed_load_avg, 0); sa->load_avg = max_t(long, sa->load_avg - r, 0); sa->load_sum = max_t(s64, sa->load_sum - r * LOAD_AVG_MAX, 0); + removed = 1; } if (atomic_long_read(&cfs_rq->removed_util_avg)) { @@ -2688,7 +2689,7 @@ static inline int update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq) cfs_rq->load_last_update_time_copy = sa->last_update_time; #endif - return decayed; + return decayed || removed; } /* Update task and its cfs_rq load average */ -- 2.20.1