From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj@kernel.org>
Subject: Re: [PATCH] cgroup: pids: use {READ,WRITE}_ONCE for pids->limit
 operations
Date: Mon, 14 Oct 2019 08:41:36 -0700
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To: Aleksa Sarai <cyphar@cyphar.com>
Cc: Li Zefan <lizefan@huawei.com>, Johannes Weiner <hannes@cmpxchg.org>, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org

On Sat, Oct 12, 2019 at 12:05:39PM +1100, Aleksa Sarai wrote:
> Because pids->limit can be changed concurrently (but we don't want to
> take a lock because it would be needlessly expensive), use the
> appropriate memory barriers.

I can't quite tell what problem it's fixing.  Can you elaborate a
scenario where the current code would break that your patch fixes?

Thanks.

-- 
tejun