Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:2 as permitted sender) client-ip=2620:137:e000::3:2;
MIME-Version: 1.0
References: <20231213013807.897742-1-schatzberg.dan@gmail.com> <20231213013807.897742-3-schatzberg.dan@gmail.com>
In-Reply-To: <20231213013807.897742-3-schatzberg.dan@gmail.com>
From:   Yu Zhao <yuzhao@google.com>
Date:   Tue, 12 Dec 2023 19:05:36 -0700
Message-ID: <CAOUHufarKA5-NGErYzvqeKKJze1XSUcMx4ntBHx2jmAUeqAioA@mail.gmail.com>
Subject: Re: [PATCH V4 2/2] mm: add swapiness= arg to memory.reclaim
To:     Dan Schatzberg <schatzberg.dan@gmail.com>
Cc:     Johannes Weiner <hannes@cmpxchg.org>,
        Roman Gushchin <roman.gushchin@linux.dev>,
        Yosry Ahmed <yosryahmed@google.com>, Huan Yang <link@vivo.com>,
        linux-kernel@vger.kernel.org, cgroups@vger.kernel.org,
        linux-mm@kvack.org, Tejun Heo <tj@kernel.org>,
        Zefan Li <lizefan.x@bytedance.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Michal Hocko <mhocko@kernel.org>,
        Shakeel Butt <shakeelb@google.com>,
        Muchun Song <muchun.song@linux.dev>,
        Andrew Morton <akpm@linux-foundation.org>,
        David Hildenbrand <david@redhat.com>,
        Matthew Wilcox <willy@infradead.org>,
        Kefeng Wang <wangkefeng.wang@huawei.com>,
        Yue Zhao <findns94@gmail.com>, Hugh Dickins <hughd@google.com>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Precedence: bulk

On Tue, Dec 12, 2023 at 6:39=E2=80=AFPM Dan Schatzberg <schatzberg.dan@gmai=
l.com> wrote:
>
> Allow proactive reclaimers to submit an additional swappiness=3D<val>
> argument to memory.reclaim. This overrides the global or per-memcg
> swappiness setting for that reclaim attempt.
>
> For example:
>
> echo "2M swappiness=3D0" > /sys/fs/cgroup/memory.reclaim
>
> will perform reclaim on the rootcg with a swappiness setting of 0 (no
> swap) regardless of the vm.swappiness sysctl setting.
>
> Signed-off-by: Dan Schatzberg <schatzberg.dan@gmail.com>

NAK.

Please initialize new variables properly and test code changes
thoroughly before submission.