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From:   Yosry Ahmed <yosryahmed@google.com>
Date:   Tue, 25 Jul 2023 12:25:03 -0700
Message-ID: <CAJD7tkb47j48TkpH=zwdJZqo5QBehVmyeMMekd6JSbNbR7XLMw@mail.gmail.com>
Subject: Re: [PATCH] mm: memcg: use rstat for non-hierarchical stats
To:     Andrew Morton <akpm@linux-foundation.org>
Cc:     Johannes Weiner <hannes@cmpxchg.org>,
        Michal Hocko <mhocko@kernel.org>,
        Roman Gushchin <roman.gushchin@linux.dev>,
        Shakeel Butt <shakeelb@google.com>,
        Muchun Song <muchun.song@linux.dev>,
        linux-kernel@vger.kernel.org, cgroups@vger.kernel.org,
        linux-mm@kvack.org
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On Tue, Jul 25, 2023 at 10:43=E2=80=AFAM Andrew Morton
<akpm@linux-foundation.org> wrote:
>
> On Tue, 25 Jul 2023 10:04:35 -0400 Johannes Weiner <hannes@cmpxchg.org> w=
rote:
>
> > > Signed-off-by: Yosry Ahmed <yosryahmed@google.com>
> >
> > Acked-by: Johannes Weiner <hannes@cmpxchg.org>
> >
> > But I want to be clear: this isn't a regression fix. It's a new
> > performance optimization for the deprecated cgroup1 code. And it comes
> > at the cost of higher memory footprint for both cgroup1 AND cgroup2.
>
> Thanks.
>
> Yosry, could you please send along a suitably modified changelog?

I will send a v2 once we agree on the history story and whether or not
this fixes a regression.

Thanks!