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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id B5921E77188 for ; Tue, 14 Jan 2025 12:19:45 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 4CF776B007B; Tue, 14 Jan 2025 07:19:45 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 47F646B0083; Tue, 14 Jan 2025 07:19:45 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 346DF6B0085; Tue, 14 Jan 2025 07:19:45 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 174366B007B for ; Tue, 14 Jan 2025 07:19:45 -0500 (EST) Received: from smtpin22.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id BE717160923 for ; 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imf05.hostedemail.com; dkim=none; spf=pass (imf05.hostedemail.com: domain of chenridong@huaweicloud.com designates 45.249.212.56 as permitted sender) smtp.mailfrom=chenridong@huaweicloud.com; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1736857182; a=rsa-sha256; cv=none; b=NAWVZbOGBLS3v1vYaBGT6IDkuEyp4PVHxeHUHypk3xhBs9171UAslK2Fqpq/R/Utf79M4c k2JQQF/1NBGAoGy++YLfYfTyYGL1qtRB750jW6f35kvniieE2nhEkrkbJgvdCv8NGp2B0S 3ScdSwL1EQqvBfmcf0DMaor5Hb7RjK4= Received: from mail.maildlp.com (unknown [172.19.163.235]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4YXSq72GNSz4f3jdG for ; Tue, 14 Jan 2025 20:19:15 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.252]) by mail.maildlp.com (Postfix) with ESMTP id ACC8A1A0B92 for ; Tue, 14 Jan 2025 20:19:35 +0800 (CST) Received: from [10.67.109.79] (unknown [10.67.109.79]) by APP3 (Coremail) with SMTP id _Ch0CgC3V8JXVoZnvH+uAw--.4723S2; Tue, 14 Jan 2025 20:19:35 +0800 (CST) Message-ID: <0d9ea655-5c1a-4ba9-9eeb-b45d74cc68d0@huaweicloud.com> Date: Tue, 14 Jan 2025 20:19:35 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3] memcg: fix soft lockup in the OOM process To: Michal Hocko , Vlastimil Babka Cc: Andrew Morton , hannes@cmpxchg.org, yosryahmed@google.com, roman.gushchin@linux.dev, shakeel.butt@linux.dev, muchun.song@linux.dev, davidf@vimeo.com, handai.szj@taobao.com, rientjes@google.com, kamezawa.hiroyu@jp.fujitsu.com, RCU , linux-mm@kvack.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, chenridong@huawei.com, wangweiyang2@huawei.com References: <20241224025238.3768787-1-chenridong@huaweicloud.com> <1ea309c1-d0f8-4209-b0b0-e69ad4e986ae@suse.cz> <58caaa4f-cf78-4d0f-af31-8a9277b6ebf5@huaweicloud.com> <20250113194546.3de1af46fa7a668111909b63@linux-foundation.org> Content-Language: en-US From: Chen Ridong In-Reply-To: Content-Type: text/plain; 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The code to iterate over all processes >>> under RCU is there (basically) since ever and yet we do not seem to have >>> many reports of stalls? Chen's situation is specific to memcg OOM and >>> touching the global case was mostly for consistency reasons. >> >> Then I'd rather not touch the global case then if it's theoretical? > > No strong opinion on this on my side. The only actual reason > touch_softlockup_watchdog is there is becuase it originally had > incorrectly cond_resched there. If half silencing (soft lock up > detector only) disturbs people then let's just drop that hunk. So do I. If there are no other opinions, I will drop it. Best regards, Ridong