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Sender: Tejun Heo <htejun@gmail.com>
Date:   Thu, 21 Apr 2022 14:00:56 -1000
From:   Tejun Heo <tj@kernel.org>
To:     Michal =?iso-8859-1?Q?Koutn=FD?= <mkoutny@suse.com>
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Subject: Re: [PATCH] cgroup: don't queue css_release_work if one already
 pending
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On Thu, Apr 14, 2022 at 06:44:09PM +0200, Michal Koutn? wrote:
> I suspect the double-queuing is a result of the fact that there exists
> only the single reference to the css->refcnt. I.e. it's
> percpu_ref_kill_and_confirm()'d and released both at the same time.
> 
> (Normally (when not killing the last reference), css->destroy_work reuse
> is not a problem because of the sequenced chain
> css_killed_work_fn()->css_put()->css_release().)

If this is the case, we need to hold an extra reference to be put by the
css_killed_work_fn(), right?

Thanks.

-- 
tejun