From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj@kernel.org>
Subject: Re: [PATCH 1/2] cgroup: pids: show number of failed forks since
 limit reset
Date: Sun, 26 Jun 2016 19:42:58 -0400
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To: Aleksa Sarai <asarai@suse.de>
Cc: Jonathan Corbet <corbet@lwn.net>, Li Zefan <lizefan@huawei.com>, Johannes Weiner <hannes@cmpxchg.org>, Kenny Yu <kennyyu@fb.com>, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org

Hello,

On Sun, Jun 26, 2016 at 09:34:41PM +1000, Aleksa Sarai wrote:
> If a user has a setup where they wait for notifications on changes to
> pids.event, and then auto-adjust the cgroup limits based on the number of
> failures you have a race condition between reading the pids.event file and
> then setting the new limit. Then, upon getting notified again there may have
> been many failed forks with the old limit set, so you might decide to bump
> up the limit again.
> 
> It's not a huge deal, I just though it could be useful to alleviate problems
> like the above.

This is something which can easily be avoided from userland.  I don't
think we need to add extra facilities for this.

Thanks.

-- 
tejun