From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from dggsgout11.his.huawei.com (dggsgout11.his.huawei.com [45.249.212.51]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 60C5F1D8DEE; Wed, 12 Feb 2025 03:24:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.51 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739330686; cv=none; b=iIBxR+QriFiqSNczgvpayRRBJH9goILDn0PQpEv9IrSEu9HtLvj4upfrvj8vfqOJpxSrTuu+cGFoV1M7wKqe0uEf1zqAD4ag0Ug8yLn5RyGcTJvb7jK7WZY5f4NCpkZRePT6GeSeOCOScQi6Aoanb9NX67VhLzAJubSKbsIFM6M= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739330686; c=relaxed/simple; bh=D6rd0kRCvnMgB1deU5946QLL3NJQk4kXAS0NXcvduu0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=trPsGtnSQs0ff3XMeG6NDwRZRQSqWFobemdnKfVHs6Gc7mkCGRDiQqOVjlbpHlRAqwTdIEmRPZ5r0Nlj5kMN+5QWaCM1grJU4k5/5oRMzcqiFCM8e5qqry3rFqe7/1MpJgqY4IjtU7uNCDbK3TIM/Fo0JvipjffDicxALCOAwLU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.51 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.93.142]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4Yt3ZS1gZpz4f3kvf; Wed, 12 Feb 2025 11:24:16 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.75]) by mail.maildlp.com (Postfix) with ESMTP id E78AB1A0D7E; Wed, 12 Feb 2025 11:24:38 +0800 (CST) Received: from [10.67.109.79] (unknown [10.67.109.79]) by APP2 (Coremail) with SMTP id Syh0CgDX4GNzFKxnNpxXDg--.64293S2; Wed, 12 Feb 2025 11:24:36 +0800 (CST) Message-ID: Date: Wed, 12 Feb 2025 11:24:35 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] mm/oom_kill: revert watchdog reset in global OOM process To: akpm@linux-foundation.org, mhocko@kernel.org, hannes@cmpxchg.org, yosryahmed@google.com, roman.gushchin@linux.dev, shakeel.butt@linux.dev, muchun.song@linux.dev, davidf@vimeo.com, vbabka@suse.cz, mkoutny@suse.com, paulmck@kernel.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, chenridong@huawei.com, wangweiyang2@huawei.com References: <20250212025707.67009-1-chenridong@huaweicloud.com> Content-Language: en-US From: Chen Ridong In-Reply-To: <20250212025707.67009-1-chenridong@huaweicloud.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-CM-TRANSID:Syh0CgDX4GNzFKxnNpxXDg--.64293S2 X-Coremail-Antispam: 1UD129KBjvJXoW7urWxuryrWryrKF1xCr1UGFg_yoW8Aryxpa yDu3WUKws8ta45Z3W7ZrWI9F17J3yrZr48tF9rt34rZwsxtrn2krWIkrnIqr95AFZI9a4Y vFnIgrn7JrZ0qw7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUv0b4IE77IF4wAFF20E14v26r4j6ryUM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rwA2F7IY1VAKz4 vEj48ve4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7Cj xVAFwI0_Gr1j6F4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x 0267AKxVW0oVCq3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG 6I80ewAv7VC0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFV Cjc4AY6r1j6r4UM4x0Y48IcVAKI48JM4IIrI8v6xkF7I0E8cxan2IY04v7MxkF7I0En4kS 14v26r1q6r43MxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY6r1j6r4UMI8I3I0E5I 8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17CEb7AF67AKxVW8ZVWr XwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY1x 0267AKxVW8JVWxJwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_ Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxVW8JVW8JrUvcSsGvfC2KfnxnUUI43ZEXa7IU1 7KsUUUUUU== X-CM-SenderInfo: hfkh02xlgr0w46kxt4xhlfz01xgou0bp/ On 2025/2/12 10:57, Chen Ridong wrote: > From: Chen Ridong > > Unlike memcg OOM, which is relatively common, global OOM events are rare > and typically indicate that the entire system is under severe memory > pressure. The commit ade81479c7dd ("memcg: fix soft lockup in the OOM > process") added the touch_softlockup_watchdog in the global OOM handler to > suppess the soft lockup issues. However, while this change can suppress > soft lockup warnings, it does not address RCU stalls, which can still be > detected and may cause unnecessary disturbances. Simply remove the > modification from the global OOM handler. > > Fixes: ade81479c7dd ("memcg: fix soft lockup in the OOM process") > Signed-off-by: Chen Ridong > --- > mm/oom_kill.c | 8 +------- > 1 file changed, 1 insertion(+), 7 deletions(-) > > diff --git a/mm/oom_kill.c b/mm/oom_kill.c > index 25923cfec9c6..2d8b27604ef8 100644 > --- a/mm/oom_kill.c > +++ b/mm/oom_kill.c > @@ -44,7 +44,6 @@ > #include > #include > #include > -#include > > #include > #include "internal.h" > @@ -431,15 +430,10 @@ static void dump_tasks(struct oom_control *oc) > mem_cgroup_scan_tasks(oc->memcg, dump_task, oc); > else { > struct task_struct *p; > - int i = 0; > > rcu_read_lock(); > - for_each_process(p) { > - /* Avoid potential softlockup warning */ > - if ((++i & 1023) == 0) > - touch_softlockup_watchdog(); > + for_each_process(p) > dump_task(p, oc); > - } > rcu_read_unlock(); > } > } Add discussion link: https://lore.kernel.org/cgroups/0d9ea655-5c1a-4ba9-9eeb-b45d74cc68d0@huaweicloud.com/