The following commit has been merged into the sched/core branch of tip: Commit-ID: e4fe074d6c359c19b74564fa1364fe48343cfa5d Gitweb: https://git.kernel.org/tip/e4fe074d6c359c19b74564fa1364fe48343cfa5d Author: Chengming Zhou <zhouchengming@xxxxxxxxxxxxx> AuthorDate: Thu, 18 Aug 2022 20:48:05 +08:00 Committer: Peter Zijlstra <peterz@xxxxxxxxxxxxx> CommitterDate: Tue, 23 Aug 2022 11:01:20 +02:00 sched/fair: Don't init util/runnable_avg for !fair task post_init_entity_util_avg() init task util_avg according to the cpu util_avg at the time of fork, which will decay when switched_to_fair() some time later, we'd better to not set them at all in the case of !fair task. Suggested-by: Vincent Guittot <vincent.guittot@xxxxxxxxxx> Signed-off-by: Chengming Zhou <zhouchengming@xxxxxxxxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Reviewed-by: Vincent Guittot <vincent.guittot@xxxxxxxxxx> Link: https://lore.kernel.org/r/20220818124805.601-10-zhouchengming@xxxxxxxxxxxxx --- kernel/sched/fair.c | 28 ++++++++++++++-------------- 1 file changed, 14 insertions(+), 14 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index ef325b5..e8c1b88 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -833,20 +833,6 @@ void post_init_entity_util_avg(struct task_struct *p) long cpu_scale = arch_scale_cpu_capacity(cpu_of(rq_of(cfs_rq))); long cap = (long)(cpu_scale - cfs_rq->avg.util_avg) / 2; - if (cap > 0) { - if (cfs_rq->avg.util_avg != 0) { - sa->util_avg = cfs_rq->avg.util_avg * se->load.weight; - sa->util_avg /= (cfs_rq->avg.load_avg + 1); - - if (sa->util_avg > cap) - sa->util_avg = cap; - } else { - sa->util_avg = cap; - } - } - - sa->runnable_avg = sa->util_avg; - if (p->sched_class != &fair_sched_class) { /* * For !fair tasks do: @@ -861,6 +847,20 @@ void post_init_entity_util_avg(struct task_struct *p) se->avg.last_update_time = cfs_rq_clock_pelt(cfs_rq); return; } + + if (cap > 0) { + if (cfs_rq->avg.util_avg != 0) { + sa->util_avg = cfs_rq->avg.util_avg * se->load.weight; + sa->util_avg /= (cfs_rq->avg.load_avg + 1); + + if (sa->util_avg > cap) + sa->util_avg = cap; + } else { + sa->util_avg = cap; + } + } + + sa->runnable_avg = sa->util_avg; } #else /* !CONFIG_SMP */
![]() |