From: Chengming Zhou <zhouchengming@bytedance.com>
To: mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com,
vincent.guittot@linaro.org, dietmar.eggemann@arm.com,
rostedt@goodmis.org, bsegall@google.com, vschneid@redhat.com
Cc: linux-kernel@vger.kernel.org,
Chengming Zhou <zhouchengming@bytedance.com>
Subject: [PATCH v4 9/9] sched/fair: don't init util/runnable_avg for !fair task
Date: Mon, 8 Aug 2022 20:57:45 +0800 [thread overview]
Message-ID: <20220808125745.22566-10-zhouchengming@bytedance.com> (raw)
In-Reply-To: <20220808125745.22566-1-zhouchengming@bytedance.com>
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@linaro.org>
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
---
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 2063e30b2a8f..082174cb0e47 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 */
--
2.36.1
prev parent reply other threads:[~2022-08-08 12:59 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-08-08 12:57 [PATCH v4 0/9] sched/fair: task load tracking optimization and cleanup Chengming Zhou
2022-08-08 12:57 ` [PATCH v4 1/9] sched/fair: maintain task se depth in set_task_rq() Chengming Zhou
2022-08-08 12:57 ` [PATCH v4 2/9] sched/fair: remove redundant cpu_cgrp_subsys->fork() Chengming Zhou
2022-08-08 12:57 ` [PATCH v4 3/9] sched/fair: reset sched_avg last_update_time before set_task_rq() Chengming Zhou
2022-08-08 12:57 ` [PATCH v4 4/9] sched/fair: update comments in enqueue/dequeue_entity() Chengming Zhou
2022-08-08 12:57 ` [PATCH v4 5/9] sched/fair: combine detach into dequeue when migrating task Chengming Zhou
2022-08-08 12:57 ` [PATCH v4 6/9] sched/fair: fix another detach on unattached task corner case Chengming Zhou
2022-08-17 15:01 ` Vincent Guittot
2022-08-17 15:04 ` Chengming Zhou
2022-08-17 15:08 ` Vincent Guittot
2022-08-17 15:10 ` Chengming Zhou
2022-08-08 12:57 ` [PATCH v4 7/9] sched/fair: allow changing cgroup of new forked task Chengming Zhou
2022-08-08 14:57 ` Chengming Zhou
2022-08-08 16:42 ` kernel test robot
2022-08-15 21:11 ` Tejun Heo
2022-08-16 13:14 ` Chengming Zhou
2022-08-08 12:57 ` [PATCH v4 8/9] sched/fair: defer task sched_avg attach to enqueue_entity() Chengming Zhou
2022-08-08 12:57 ` Chengming Zhou [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20220808125745.22566-10-zhouchengming@bytedance.com \
--to=zhouchengming@bytedance.com \
--cc=bsegall@google.com \
--cc=dietmar.eggemann@arm.com \
--cc=juri.lelli@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
--cc=rostedt@goodmis.org \
--cc=vincent.guittot@linaro.org \
--cc=vschneid@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).