From mboxrd@z Thu Jan  1 00:00:00 1970
From: Roman Gushchin <guro@fb.com>
Subject: Re: [PATCH v4 3/7] cgroup: protect cgroup->nr_(dying_)descendants by
 css_set_lock
Date: Mon, 3 Dec 2018 17:55:32 +0000
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To: Tejun Heo <tj@kernel.org>
Cc: Roman Gushchin <guroan@gmail.com>, Oleg Nesterov <oleg@redhat.com>, Dan Carpenter <dan.carpenter@oracle.com>, Mike Rapoport <rppt@linux.vnet.ibm.com>, "cgroups@vger.kernel.org" <cgroups@vger.kernel.org>, "linux-doc@vger.kernel.org" <linux-doc@vger.kernel.org>, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, Kernel Team <Kernel-team@fb.com>

On Mon, Dec 03, 2018 at 08:17:06AM -0800, Tejun Heo wrote:
> On Fri, Nov 30, 2018 at 03:47:41PM -0800, Roman Gushchin wrote:
> > +	 * nr_descendants and nr_dying_descendants are protected
> > +	 * by cgroup_mutex and css_set_lock.
>=20
> Can you be a bit more specific - hold both for writes, either for
> reads.

Sure. Thanks!