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=-6.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 5F967C433E7 for ; Tue, 13 Oct 2020 23:53:09 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id E0CE4208B3 for ; Tue, 13 Oct 2020 23:53:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="GpOg8gU7" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E0CE4208B3 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 764C86B00DC; Tue, 13 Oct 2020 19:53:08 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 714346B00DD; Tue, 13 Oct 2020 19:53:08 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 603936B00DE; Tue, 13 Oct 2020 19:53:08 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0118.hostedemail.com [216.40.44.118]) by kanga.kvack.org (Postfix) with ESMTP id 311076B00DC for ; Tue, 13 Oct 2020 19:53:08 -0400 (EDT) Received: from smtpin18.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id D21483629 for ; Tue, 13 Oct 2020 23:53:07 +0000 (UTC) X-FDA: 77368555614.18.mint35_3e169a927207 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin18.hostedemail.com (Postfix) with ESMTP id B450010188D18 for ; Tue, 13 Oct 2020 23:53:07 +0000 (UTC) X-HE-Tag: mint35_3e169a927207 X-Filterd-Recvd-Size: 2912 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf03.hostedemail.com (Postfix) with ESMTP for ; Tue, 13 Oct 2020 23:53:07 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3D187206D5; Tue, 13 Oct 2020 23:53:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602633186; bh=9OjnVqTbjR3zE+/OgtAFul/0ZWu3KIYj0sbrX/HM/Hc=; h=Date:From:To:Subject:In-Reply-To:From; b=GpOg8gU75N/GtHGK12piUG1HhREXBDhGCtyhQmInMdq8qy5XrZYaVwHVOY3CWTeum 30Ru+18aol0cQn0zuTleW8WY/ZzjnB/3+rbNIfMQYlFFbJrLUTGfbR15R4M7mP71kp F6ugGYpXhE8yrlcFVVHoMi20ettyiu4EJGHhT2QQ= Date: Tue, 13 Oct 2020 16:53:05 -0700 From: Andrew Morton To: akpm@linux-foundation.org, hannes@cmpxchg.org, linmiaohe@huawei.com, linux-mm@kvack.org, mhocko@suse.com, mm-commits@vger.kernel.org, torvalds@linux-foundation.org, vdavydov.dev@gmail.com Subject: [patch 087/181] mm: memcontrol: reword obsolete comment of mem_cgroup_unmark_under_oom() Message-ID: <20201013235305.5-1oHu1qh%akpm@linux-foundation.org> In-Reply-To: <20201013164658.3bfd96cc224d8923e66a9f4e@linux-foundation.org> User-Agent: s-nail v14.8.16 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: From: Miaohe Lin Subject: mm: memcontrol: reword obsolete comment of mem_cgroup_unmark_under_oom() Since commit 79dfdaccd1d5 ("memcg: make oom_lock 0 and 1 based rather than counter"), the mem_cgroup_unmark_under_oom() is added and the comment of the mem_cgroup_oom_unlock() is moved here. But this comment make no sense here because mem_cgroup_oom_lock() does not operate on under_oom field. So we reword the comment as this would be helpful. [Thanks Michal Hocko for rewording this comment.] Link: https://lkml.kernel.org/r/20200930095336.21323-1-linmiaohe@huawei.com Signed-off-by: Miaohe Lin Acked-by: Michal Hocko Cc: Johannes Weiner Cc: Vladimir Davydov Signed-off-by: Andrew Morton --- mm/memcontrol.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/mm/memcontrol.c~mm-memcontrol-reword-obsolete-comment-of-mem_cgroup_unmark_under_oom +++ a/mm/memcontrol.c @@ -1826,8 +1826,8 @@ static void mem_cgroup_unmark_under_oom( struct mem_cgroup *iter; /* - * When a new child is created while the hierarchy is under oom, - * mem_cgroup_oom_lock() may not be called. Watch for underflow. + * Be careful about under_oom underflows becase a child memcg + * could have been added after mem_cgroup_mark_under_oom. */ spin_lock(&memcg_oom_lock); for_each_mem_cgroup_tree(iter, memcg) _