From patchwork Tue Feb 23 20:56:25 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shakeel Butt X-Patchwork-Id: 12100923 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=-16.5 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 31CFAC433E0 for ; Tue, 23 Feb 2021 21:04:42 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id A99B160235 for ; Tue, 23 Feb 2021 21:04:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A99B160235 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 153A56B0005; Tue, 23 Feb 2021 16:04:41 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 104B66B0006; Tue, 23 Feb 2021 16:04:41 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 01A7D6B006E; Tue, 23 Feb 2021 16:04:40 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0178.hostedemail.com [216.40.44.178]) by kanga.kvack.org (Postfix) with ESMTP id DED9A6B0005 for ; Tue, 23 Feb 2021 16:04:40 -0500 (EST) Received: from smtpin24.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id B07F6824805A for ; Tue, 23 Feb 2021 21:04:40 +0000 (UTC) X-FDA: 77850761520.24.A54370D Received: from mail-ot1-f73.google.com (mail-ot1-f73.google.com [209.85.210.73]) by imf19.hostedemail.com (Postfix) with ESMTP id A5CD690009D6 for ; Tue, 23 Feb 2021 21:04:36 +0000 (UTC) Received: by mail-ot1-f73.google.com with SMTP id y18so6838185otk.2 for ; Tue, 23 Feb 2021 13:04:40 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:message-id:mime-version:subject:from:to:cc; bh=VjQqR/dV9CmTvhJpIjv+GuV8z4P1stvvAwZgqfJoGxA=; b=mbSLgPRCosw1LgNbfZCQnOf60JkRnE/oZ2dfceOMIrdTSFDoq5FVwWZlenlEN3duNu LohQcoryhXyJfYxvHKWMDVRZhlyTZN7TguKnQS+JgyeHcABPQA1vfuCU7zw9y6PF1NOv vGNMRvc4MSRHE6B10Jeh5MZeB0RSzfOZyOgAKPzC3jN/FH0WswJOXI6mLvbQZC2XS8eW CD7xkAu51CFETtgUy622hl5ARPc+8WRj+WqSjXWQPSYcsO4OkXu6hPon8zk01OvAKWke aFpjOavUMmudXnqIgS/YEaSbEtC8nBwWU4YEvd78Nyscbp3L6S+HxqkqJOSntxdwCHId MHBQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:message-id:mime-version:subject:from :to:cc; bh=VjQqR/dV9CmTvhJpIjv+GuV8z4P1stvvAwZgqfJoGxA=; b=oAlEy7HEtARlmljpVQJ1fCg5gShNVvOu0F5QYP9iIUuCWahK3V4aUMpd5OUPfPXRZN 0OmJZvuhRB/a1bEPxRaeZ1jlwTqKQKodKOS19b0cRv2CP/sWsbfeetfZppHKKO3GEKpB aPJ5e+mpz4L6GC2r2YJDiH5j/Ve4URZ+5lhcOCgB6CfHcmQT/DNhWI5RJgYA7y4+site cd5IyPtP4WNPO9oPyslr9o2MfOkzefAV/eYRCTORddIAmItnS3HVmd7PtuAnsLgLjyxE vu6+fzCi/+MVMjGv9CHD3wBJWT9PlVFTrXcJcBya5SMcRGdMUsGGMo9GrLmfVE2+0++4 C3DA== X-Gm-Message-State: AOAM533xk9vFzsmQXgH1SpEg8xkBwoaS1djWpzk4DU8CNcYtqaySAg0j +UWfTy6pS9vyiad0MQX6RIb8jc1K5hCLDg== X-Google-Smtp-Source: ABdhPJwty35ymd10NafwoqU0YOhxPbcs9qNH9tWIjjldDeiHkjvYzVWjgVg+F5/TZM+guUKIA4j6kxGHHK/4sw== X-Received: from shakeelb.svl.corp.google.com ([2620:15c:2cd:202:8ccd:3283:c85b:61eb]) (user=shakeelb job=sendgmr) by 2002:a17:90a:ab8b:: with SMTP id n11mr607117pjq.85.1614113794713; Tue, 23 Feb 2021 12:56:34 -0800 (PST) Date: Tue, 23 Feb 2021 12:56:25 -0800 Message-Id: <20210223205625.2792891-1-shakeelb@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.30.0.617.g56c4b15f3c-goog Subject: [PATCH] memcg: cleanup root memcg checks From: Shakeel Butt To: Johannes Weiner , Roman Gushchin , Michal Hocko Cc: Andrew Morton , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Shakeel Butt X-Stat-Signature: ukg3xbuekj4emg9j6jt87y86mkg14g17 X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: A5CD690009D6 Received-SPF: none (flex--shakeelb.bounces.google.com>: No applicable sender policy available) receiver=imf19; identity=mailfrom; envelope-from="<3Amw1YAgKCLcpeXhbbiYdlldib.Zljifkru-jjhsXZh.lod@flex--shakeelb.bounces.google.com>"; helo=mail-ot1-f73.google.com; client-ip=209.85.210.73 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1614114276-910154 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Replace the implicit checking of root memcg with explicit root memcg checking i.e. !css->parent with mem_cgroup_is_root(). Signed-off-by: Shakeel Butt Acked-by: Michal Hocko Acked-by: Johannes Weiner --- mm/memcontrol.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index dcb5665aeb69..79046ad3eec0 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -4141,7 +4141,7 @@ static int mem_cgroup_swappiness_write(struct cgroup_subsys_state *css, if (val > 100) return -EINVAL; - if (css->parent) + if (!mem_cgroup_is_root(memcg)) memcg->swappiness = val; else vm_swappiness = val; @@ -4491,7 +4491,7 @@ static int mem_cgroup_oom_control_write(struct cgroup_subsys_state *css, struct mem_cgroup *memcg = mem_cgroup_from_css(css); /* cannot set to root cgroup and only 0 and 1 are allowed */ - if (!css->parent || !((val == 0) || (val == 1))) + if (mem_cgroup_is_root(memcg) || !((val == 0) || (val == 1))) return -EINVAL; memcg->oom_kill_disable = val;