lkml.org 
[lkml]   [2022]   [Aug]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH -next] sched/deadline: Save processing meaningless ops in dl_task_offline_migration
Date
Task's bw will be sub from old rd, and add to new rd, even though
find_lock_later_rq returns a new rq that belong to the same rd with old
rq. Save ops for moving task's bw if rd is not changed.

Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com>
---
kernel/sched/deadline.c | 28 +++++++++++++++-------------
1 file changed, 15 insertions(+), 13 deletions(-)

diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 3bf4b12ec5b7..58ca9aaa9c44 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -714,20 +714,22 @@ static struct rq *dl_task_offline_migration(struct rq *rq, struct task_struct *p
add_rq_bw(&p->dl, &later_rq->dl);
}

- /*
- * And we finally need to fixup root_domain(s) bandwidth accounting,
- * since p is still hanging out in the old (now moved to default) root
- * domain.
- */
- dl_b = &rq->rd->dl_bw;
- raw_spin_lock(&dl_b->lock);
- __dl_sub(dl_b, p->dl.dl_bw, cpumask_weight(rq->rd->span));
- raw_spin_unlock(&dl_b->lock);
+ if (&rq->rd != &later_rq->rd) {
+ /*
+ * And we finally need to fixup root_domain(s) bandwidth accounting,
+ * since p is still hanging out in the old (now moved to default) root
+ * domain.
+ */
+ dl_b = &rq->rd->dl_bw;
+ raw_spin_lock(&dl_b->lock);
+ __dl_sub(dl_b, p->dl.dl_bw, cpumask_weight(rq->rd->span));
+ raw_spin_unlock(&dl_b->lock);

- dl_b = &later_rq->rd->dl_bw;
- raw_spin_lock(&dl_b->lock);
- __dl_add(dl_b, p->dl.dl_bw, cpumask_weight(later_rq->rd->span));
- raw_spin_unlock(&dl_b->lock);
+ dl_b = &later_rq->rd->dl_bw;
+ raw_spin_lock(&dl_b->lock);
+ __dl_add(dl_b, p->dl.dl_bw, cpumask_weight(later_rq->rd->span));
+ raw_spin_unlock(&dl_b->lock);
+ }

set_task_cpu(p, later_rq->cpu);
double_unlock_balance(later_rq, rq);
--
2.17.1
\
 
 \ /
  Last update: 2022-08-27 03:30    [W:0.166 / U:0.000 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site