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Date:   Tue, 21 Dec 2021 09:52:28 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     xuhaifeng <xuhaifeng@oppo.com>
Cc:     mingo@redhat.com, juri.lelli@redhat.com, dietmar.eggemann@arm.com,
        rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de,
        bristot@redhat.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] sched: optimize __cond_resched_lock()
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On Tue, Dec 21, 2021 at 03:23:16PM +0800, xuhaifeng wrote:
> if the kernel is preemptible(CONFIG_PREEMPTION=y), schedule()may be
> called twice, once via spin_unlock, once via preempt_schedule_common.
> 
> we can add one conditional, check TIF_NEED_RESCHED flag again,
> to avoid this.

You can also make it more similar to __cond_resched() instead of making
it more different.