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 X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F061AC433ED for ; Fri, 9 Apr 2021 12:32:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C9316610CA for ; Fri, 9 Apr 2021 12:32:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233505AbhDIMcN (ORCPT ); Fri, 9 Apr 2021 08:32:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59030 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231370AbhDIMcL (ORCPT ); Fri, 9 Apr 2021 08:32:11 -0400 Received: from mail-pj1-x1035.google.com (mail-pj1-x1035.google.com [IPv6:2607:f8b0:4864:20::1035]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B0C98C061760 for ; Fri, 9 Apr 2021 05:31:58 -0700 (PDT) Received: by mail-pj1-x1035.google.com with SMTP id ep1-20020a17090ae641b029014d48811e37so3109718pjb.4 for ; Fri, 09 Apr 2021 05:31:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=58kw73zULk1M3QRMYpGesyQhzu0BFPE8Fnems3AjAyI=; b=jSUh5hJWnp8EpV/wkefSJdZoi2UIab+EAWPvsDiKxRQZFhbegQ6L+Dl6eawxYH4xVP Z5VSbvD4uyhDlqJvsvJE7nm/k4W55DfqLKoNSuW9g0pMbgvsj6VyLm54oHXzQYVgaYOE 1eLC/i/3dlP0Ne5mvo6Zr5HbA191dng758K50uL4U8eC04wsiOi6hu06CioZQfggRe1l cTX182sfC625GWoWUSxyVFANLDFjhgIeRuJ8PabTFygDuLtG7KPWnb+YCntxJixUVreS fnBFBvxfh8qKkvW8XSdGg6kg0d4QTUqphO4HAAsi7LIkqyhWlhrUvL9nB9J62VMFJRCT AIQw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=58kw73zULk1M3QRMYpGesyQhzu0BFPE8Fnems3AjAyI=; b=MhLrPTpnvWdfLFfqzRvwEoDLIG00KhwBhRYcLfGFBsYmrZsPDOA/s45WRhFP9Ba3QO rE3GRuwfJZ5AWkehK//hFKcxP754YlMFmNk0gtQpe7YTXVa5E8syxnlWNcXZ711EUrHS WBkAGGNfs9cOYKu+D/0lwhQA4ipuW5Ub9JMxEhYX7RI2Me+zNThVU1kFfb+MQ4Fkb6WU XCAx7iATPECEnGR6NsYeJbMV2OCLAYAhvvhKcCWMgavAIoHRAVD5h/88L5bj71hDkugD YNM1Czj+x7U4IJcLteqgjaBe3FzADQLJNaes5znzgtM014dmFjcFAtZYuJR5QQusBDUk dX5Q== X-Gm-Message-State: AOAM531v6KG+PMRXQXVTWyx0qxCh7OtNDsDX5jSxZWtSEXghA8ICvOEj xDQW3W4e8Xbm46J9qeBylqgyFA== X-Google-Smtp-Source: ABdhPJxT5HnFu/JWiq7mOhBolL3h47S0OslJDo9Gs2/ZnJOGN15SbV0U6S25bb3U+N8skATR+PwuPQ== X-Received: by 2002:a17:90a:e016:: with SMTP id u22mr13094679pjy.134.1617971518281; Fri, 09 Apr 2021 05:31:58 -0700 (PDT) Received: from localhost.localdomain ([139.177.225.243]) by smtp.gmail.com with ESMTPSA id t3sm2167785pfg.176.2021.04.09.05.31.53 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Fri, 09 Apr 2021 05:31:57 -0700 (PDT) From: Muchun Song To: guro@fb.com, hannes@cmpxchg.org, mhocko@kernel.org, akpm@linux-foundation.org, shakeelb@google.com, vdavydov.dev@gmail.com Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, duanxiongchun@bytedance.com, fam.zheng@bytedance.com, bsingharora@gmail.com, shy828301@gmail.com, alex.shi@linux.alibaba.com, Muchun Song Subject: [RFC PATCH v2 01/18] mm: memcontrol: fix page charging in page replacement Date: Fri, 9 Apr 2021 20:29:42 +0800 Message-Id: <20210409122959.82264-2-songmuchun@bytedance.com> X-Mailer: git-send-email 2.21.0 (Apple Git-122) In-Reply-To: <20210409122959.82264-1-songmuchun@bytedance.com> References: <20210409122959.82264-1-songmuchun@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The pages aren't accounted at the root level, so do not charge the page to the root memcg in page replacement. Although we do not display the value (mem_cgroup_usage) so there shouldn't be any actual problem, but there is a WARN_ON_ONCE in the page_counter_cancel(). Who knows if it will trigger? So it is better to fix it. Signed-off-by: Muchun Song Acked-by: Johannes Weiner --- mm/memcontrol.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 64ada9e650a5..f229de925aa5 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -6806,9 +6806,11 @@ void mem_cgroup_migrate(struct page *oldpage, struct page *newpage) /* Force-charge the new page. The old one will be freed soon */ nr_pages = thp_nr_pages(newpage); - page_counter_charge(&memcg->memory, nr_pages); - if (do_memsw_account()) - page_counter_charge(&memcg->memsw, nr_pages); + if (!mem_cgroup_is_root(memcg)) { + page_counter_charge(&memcg->memory, nr_pages); + if (do_memsw_account()) + page_counter_charge(&memcg->memsw, nr_pages); + } css_get(&memcg->css); commit_charge(newpage, memcg); -- 2.11.0