From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 04550C7619A for ; Mon, 27 Mar 2023 01:29:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229887AbjC0B3n (ORCPT ); Sun, 26 Mar 2023 21:29:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51664 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229456AbjC0B3m (ORCPT ); Sun, 26 Mar 2023 21:29:42 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 29BF544BE; Sun, 26 Mar 2023 18:29:41 -0700 (PDT) Received: from kwepemi500024.china.huawei.com (unknown [172.30.72.53]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4PlFZT0mWszrX6N; Mon, 27 Mar 2023 09:28:33 +0800 (CST) Received: from [10.67.109.31] (10.67.109.31) by kwepemi500024.china.huawei.com (7.221.188.100) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.21; Mon, 27 Mar 2023 09:29:38 +0800 Message-ID: Date: Mon, 27 Mar 2023 09:29:37 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.5.1 Subject: Re: [PATCH 1/1] mm: memcontrol: fix vmstats_percpu state incorrect subtraction after reparent References: <20230320030648.50663-1-caixinchen1@huawei.com> <20230320030648.50663-2-caixinchen1@huawei.com> <20230324171114.32oru5sdubfsfvgi@blackpad> To: From: Cai Xinchen CC: , , , , , , , , , , , , In-Reply-To: <20230324171114.32oru5sdubfsfvgi@blackpad> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.67.109.31] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To kwepemi500024.china.huawei.com (7.221.188.100) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Yes, only cgroup v1. On 2023/3/25 1:11, Michal Koutný wrote: > Hello. > > On Mon, Mar 20, 2023 at 03:06:48AM +0000, Cai Xinchen wrote: >> When memcg C is offllined, its pages are reparented to memcg P, >> so far P->vmstats (hierarchical) have those pages, and >> P->vmstats_percpu (non-hierarchical) don't. When those pages get >> uncharged, P->vmstats (hierachical) decreases, which is correct, >> but P->vmstats_percpu (non-hierarchical) also decreases, which >> is wrong, as those stats were never added to P->vmstats_percpu to >> begin with. > I was wondering why ->vmstats_percpu matters (in the end all is summed > in ->vmstats) -- do you mean this is a cgroup v1 only issue? As only > that exposes the non-hieararchical stats. > > Thanks, > Michal