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From:   Wang You <wangyoua@uniontech.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, mgorman@suse.de,
        bristot@redhat.com, vschneid@redhat.com
Cc:     linux-kernel@vger.kernel.org, Wang You <wangyoua@uniontech.com>
Subject: [RFC] remove preempt in do_sched_yield
Date:   Wed, 23 Aug 2023 18:07:05 +0800
Message-Id: <20230823100705.5363-1-wangyoua@uniontech.com>
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I see do_sched_yield's irq disable cover preempt disable. In this
function, I think preempt op may not work, or it may have some
special effect ? Thanks.

Signed-off-by: Wang You <wangyoua@uniontech.com>
---
 kernel/sched/core.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index a68d1276bab0..b255e54c1d38 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -8487,10 +8487,7 @@ static void do_sched_yield(void)
 
 	schedstat_inc(rq->yld_count);
 	current->sched_class->yield_task(rq);
-
-	preempt_disable();
 	rq_unlock_irq(rq, &rf);
-	sched_preempt_enable_no_resched();
 
 	schedule();
 }
-- 
2.20.1