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Date:   Tue, 26 Sep 2023 00:29:57 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Liu Shixin <liushixin2@huawei.com>
Cc:     Yosry Ahmed <yosryahmed@google.com>, Tejun Heo <tj@kernel.org>,
        Zefan Li <lizefan.x@bytedance.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Jonathan Corbet <corbet@lwn.net>,
        Michal Hocko <mhocko@kernel.org>,
        Roman Gushchin <roman.gushchin@linux.dev>,
        Shakeel Butt <shakeelb@google.com>,
        Muchun Song <muchun.song@linux.dev>,
        Kefeng Wang <wangkefeng.wang@huawei.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        cgroups@vger.kernel.org, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [PATCH] mm, memcg: expose swapcache stat for memcg v1
Message-ID: <ZRKIdTE+4cm0KDCI@infradead.org>
References: <20230902100728.3850149-1-liushixin2@huawei.com>
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On Sat, Sep 02, 2023 at 06:07:28PM +0800, Liu Shixin wrote:
> Since commit b6038942480e ("mm: memcg: add swapcache stat for memcg v2")
> adds swapcache stat for the cgroup v2, it seems there is no reason to
> hide it in memcg v1. Conversely, with swapcached it is more accurate to
> evaluate the available memory for memcg.

Why are we adding new features to the long deprecated cgroup v1?