Re: [PATCH 1/5] cgroups: Refactor children cgroups in memcg tests

From: David Vernet <void@manifault.com>
To: Roman Gushchin <roman.gushchin@linux.dev>
Cc: akpm@linux-foundation.org, tj@kernel.org,
	linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	cgroups@vger.kernel.org, hannes@cmpxchg.org, mhocko@kernel.org,
	shakeelb@google.com, kernel-team@fb.com
Subject: Re: [PATCH 1/5] cgroups: Refactor children cgroups in memcg tests
Date: Sat, 23 Apr 2022 04:30:37 -0700	[thread overview]
Message-ID: <20220423113037.gnfysktiuzmfnpmp@dev0025.ash9.facebook.com> (raw)
In-Reply-To: <YmM0b+3thMZaXVDb@carbon>

On Fri, Apr 22, 2022 at 04:04:15PM -0700, Roman Gushchin wrote:
>

Thanks for the reviews on this patchset, Roman. FYI I think Andrew already
merged these patches to the -mm tree. I'll send out a follow-on patch that
fixes everything you pointed out, both here and on the other patches in the
set.

> On Fri, Apr 22, 2022 at 08:57:25AM -0700, David Vernet wrote:
> > In test_memcg_min() and test_memcg_low(), there is an array of four sibling
> > cgroups. All but one of these sibling groups does a 50MB allocation, and
> > the group that does no allocation is the third of four in the array.  This
> > is not a problem per se, but makes it a bit tricky to do some assertions in
> > test_memcg_low(), as we want to make assertions on the siblings based on
> > whether or not they performed allocations. Having a static index before
> > which all groups have performed an allocation makes this cleaner.
> > 
> > This patch therefore reorders the sibling groups so that the group that
> > performs no allocations is the last in the array.
> 
> It makes the comment explaining the test just above the test_memcg_min()
> function obsolete. Please, fix it too.

Thanks for catching that. I'll fix the comment both in test_memcg_min() and
test_memcg_low() when I send out that follow-on patch.