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b=Iuaa2ASFYi8g49KLLXEzA+HefzGQsNEMIPsfpsoiouhzmRqgPB/QEBTXx9j312Y2E WckvlwtBI8SsH47XbWgM/D8zHxJZkBSYaGfjM7A46Hs3r70KUv3YlUJveZXw/Y10Hv xbGjFz/1sm543DrckGD9DHLiFnfZK6ch67XWAwKN1CWZrQoZ6ke4RKT/66f9bzpQD5 9d8xXsynjcE0ruWoytE+WdKpGJmFjFrnoT0jjTKAz7IJABW+hKL5bLL49HWkr2hk42 +g2/rNL6m41kLbrV2tkNeklAINFjBn/ju/xLaQDdCM7yYFDFRycGvTwV5Uyo/jkmal Pz0io5oi4CfNw== Message-ID: <1150896f-de20-4672-b498-6c9dd17e4aca@kernel.org> Date: Thu, 6 Aug 2026 15:51:49 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH v5 1/4] mm: add page_counter_margin() To: Xueyuan Chen , akpm@linux-foundation.org, linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, zhaonanzhe@xiaomi.com, baohua@kernel.org, hannes@cmpxchg.org, youngjun.park@lge.com, baolin.wang@linux.alibaba.com, hughd@google.com, chrisl@kernel.org, kasong@tencent.com, shikemeng@huaweicloud.com, nphamcs@gmail.com, baoquan.he@linux.dev, mhocko@kernel.org, roman.gushchin@linux.dev, shakeel.butt@linux.dev, muchun.song@linux.dev, ljs@kernel.org, liam@infradead.org, vbabka@kernel.org, rppt@kernel.org, surenb@google.com, qi.zheng@linux.dev, axelrasmussen@google.com, yuanchu@google.com, weixugc@google.com References: <20260730122304.2496440-1-xueyuan.chen21@gmail.com> <20260730122304.2496440-2-xueyuan.chen21@gmail.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 8BE7112000C X-Stat-Signature: k1qxgb9quwpjatjudmy3byozcy3mwtj7 X-HE-Tag: 1786024320-24695 X-HE-Meta: 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 peNy1IZ7 PlOVMfKXINACBe6upvN3Xdze+IpxG3DmcXLBO3GZU2tUu0r33ikxkUlbsJTYV2cmzlSbgDeeVkzmqdyLviDNvrtFlu8//ZbVBqXPWpqukZrlB6jUnDffKMd2nKpHfyqVsqJTeVb0MLrL1Cnx9Nby1UDbsBvpoPOfaN+S/JWeT32vFAxI/qRLzr6P8YVu+Spj0BbH0UQKr2r3jU9kYFAOtwsDrVhvwS03wgrjXEmme7YNuNlEAOoyzdV9YzuJRFDJ8qGy/smeJL1Jk6g4OyUR4fn0xbV1bE78wK8xXhgX2iAb63lw2pNM9TV4x/n3rO+xafncOomI0ioiwSsMq7BScAF/nuSXHbQKb3eipCjgChlwAaHJUgmuOdKddm4ZLGVwHb2uylQ572IvVNCuu7jjObwgXzHnWc22G7Kk5MHIbiscQkLcuv2lUuCBS6+3u7GHZfU7S8hE+Fxkur2rJcH3d0/KXQIHa8ccmRijHLp1RqpeN8nI= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 7/30/26 14:23, Xueyuan Chen wrote: > From: Johannes Weiner > > mem_cgroup_get_nr_swap_pages() open-codes the remaining capacity across > the memcg swap counter hierarchy. > > Add page_counter_margin() to return the minimum usable space from a page > counter to the root, and use it in mem_cgroup_get_nr_swap_pages(). This > is a pure refactoring with no intended behavior change. > > Signed-off-by: Johannes Weiner > Signed-off-by: Xueyuan Chen > --- Reviewed-by: David Hildenbrand (Arm) -- Cheers, David