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From:   Lai Jiangshan <jiangshanlai@gmail.com>
Date:   Thu, 4 Aug 2022 18:19:08 +0800
Message-ID: <CAJhGHyDfRGOS0v8vA7Lf+W2K80r2_+CndFBz9O-HXd6AtrexQA@mail.gmail.com>
Subject: Re: [PATCH] workqueue: Make create_worker() safe against spurious wakeups
To:     Petr Mladek <pmladek@suse.com>
Cc:     Tejun Heo <tj@kernel.org>, Michal Hocko <mhocko@suse.com>,
        LKML <linux-kernel@vger.kernel.org>
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On Thu, Aug 4, 2022 at 4:57 PM Lai Jiangshan <jiangshanlai@gmail.com> wrote:
         ;
>
> There might be some wakeups from wake_up_worker() since it is in
> the idle list.  These wakeups will be "spurious wakeups" in the view
> of the completion subsystem.
>


Oh, sorry, I was wrong. "complete(&worker->ready_to_start);" and
"worker_enter_idle(worker);" are in the same pool lock region.

There are no "spurious wakeups" from "wake_up_worker()" as I have
wrongly described.