From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D84B63955FA; Thu, 6 Aug 2026 13:51:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786024320; cv=none; b=Vncne8212RISpV5AOETa0fciOcrkwEgBdX+VpgobzVOeXkOGp0Gz/g0XwQ8XOfSrIqvonaBbtZf5TGGX/Qen4x4hBecvZKkTjtenDZU/QvWkD6CwgdO9OjHOPsWWqMSAc05VaVdCWMeK2lQMvBDwtIPTaO3RtTvyQTYMFVvDkTQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786024320; c=relaxed/simple; bh=EKTMi4J+pUd1lF0ny3NBTxiRJRmuv4eWT856Dj2JS2U=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=o63Uh0s76FJjw/1gt/dRi3sPJ9QxzDuqn6LaHBEAF/M45ZjgkJmJ8b7TkC/vMKVieCzieoAVnh2Tujv46EAi1brfuoXvdoPbcWoNLSSbZQdCk7XVUXlfXd5bQ20vJ6VWzzImqsg2/k78P0sTD2VBreNxSnH3banmdkQCFTvaCxw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Iuaa2ASF; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Iuaa2ASF" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A36F51F000E9; Thu, 6 Aug 2026 13:51:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1786024319; bh=mtOtoJPfPoNQ3lP/qAbd+1hDTx3C/med8KgZHUjbjqU=; h=Date:Subject:To:Cc:References:From:In-Reply-To; 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 Precedence: bulk X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: 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 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