Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20230328061638.203420-1-yosryahmed@google.com> <20230328061638.203420-10-yosryahmed@google.com>
In-Reply-To: <20230328061638.203420-10-yosryahmed@google.com>
From:   Shakeel Butt <shakeelb@google.com>
Date:   Tue, 28 Mar 2023 08:20:15 -0700
Message-ID: <CALvZod4boccrKxrCm9aDBCupror1zC0J3spHeidSiAZgei_r9Q@mail.gmail.com>
Subject: Re: [PATCH v1 9/9] memcg: do not modify rstat tree for zero updates
To:     Yosry Ahmed <yosryahmed@google.com>
Cc:     Tejun Heo <tj@kernel.org>, Josef Bacik <josef@toxicpanda.com>,
        Jens Axboe <axboe@kernel.dk>,
        Zefan Li <lizefan.x@bytedance.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Michal Hocko <mhocko@kernel.org>,
        Roman Gushchin <roman.gushchin@linux.dev>,
        Muchun Song <muchun.song@linux.dev>,
        Andrew Morton <akpm@linux-foundation.org>,
        =?UTF-8?Q?Michal_Koutn=C3=BD?= <mkoutny@suse.com>,
        Vasily Averin <vasily.averin@linux.dev>,
        cgroups@vger.kernel.org, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        bpf@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Precedence: bulk

On Mon, Mar 27, 2023 at 11:17=E2=80=AFPM Yosry Ahmed <yosryahmed@google.com=
> wrote:
>
> In some situations, we may end up calling memcg_rstat_updated() with a
> value of 0, which means the stat was not actually updated. An example is
> if we fail to reclaim any pages in shrink_folio_list().
>
> Do not add the cgroup to the rstat updated tree in this case, to avoid
> unnecessarily flushing it.
>
> Signed-off-by: Yosry Ahmed <yosryahmed@google.com>

Acked-by: Shakeel Butt <shakeelb@google.com>