Skip meaningless bw updates on root domain if task still stay in same rd
while calling dl_task_offline_migration.
Signed-off-by: Shang XiaoJing <[email protected]>
---
changes in v2:
- fix subject and comment message
---
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 8e14dc21d829..9660e166c8ec 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
On 8/29/22 13:59, Shang XiaoJing wrote:
> Skip meaningless bw updates on root domain if task still stay in same rd
> while calling dl_task_offline_migration.
>
> Signed-off-by: Shang XiaoJing <[email protected]>
Reviewed-by: Daniel Bristot de Oliveira <[email protected]>
-- Daniel