linux-kernel - [PATCH v4 2/2] sched/deadline: Remove superfluous rq clock update in push_dl

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Date:   Sat, 30 Apr 2022 16:58:43 +0800
From:   Hao Jia <jiahao.os@...edance.com>
To:     mingo@...hat.com, peterz@...radead.org, juri.lelli@...hat.com,
        vincent.guittot@...aro.org, dietmar.eggemann@....com,
        rostedt@...dmis.org, bsegall@...gle.com, mgorman@...e.de,
        bristot@...hat.com
Cc:     linux-kernel@...r.kernel.org, Hao Jia <jiahao.os@...edance.com>
Subject: [PATCH v4 2/2] sched/deadline: Remove superfluous rq clock update in push_dl_task()

The change to call update_rq_clock() before activate_task()
commit 840d719604b0 ("sched/deadline: Update rq_clock of later_rq
when pushing a task") is no longer needed since commit f4904815f97a
("sched/deadline: Fix double accounting of rq/running bw in push & pull")
removed the add_running_bw() before the activate_task().

So we remove some comments that are no longer needed and update
rq clock in activate_task().

Signed-off-by: Hao Jia <jiahao.os@...edance.com>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@....com>
Reviewed-by: Daniel Bristot de Oliveira <bristot@...hat.com>
---
 kernel/sched/deadline.c | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index b61281d10458..877f55f3a60e 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -2320,13 +2320,7 @@ static int push_dl_task(struct rq *rq)
 
 	deactivate_task(rq, next_task, 0);
 	set_task_cpu(next_task, later_rq->cpu);
-
-	/*
-	 * Update the later_rq clock here, because the clock is used
-	 * by the cpufreq_update_util() inside __add_running_bw().
-	 */
-	update_rq_clock(later_rq);
-	activate_task(later_rq, next_task, ENQUEUE_NOCLOCK);
+	activate_task(later_rq, next_task, 0);
 	ret = 1;
 
 	resched_curr(later_rq);
-- 
2.32.0