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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 2121BC433E6 for ; Thu, 18 Feb 2021 19:13:41 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id A04D864EB9 for ; Thu, 18 Feb 2021 19:13:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A04D864EB9 Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 0778A6B006C; Thu, 18 Feb 2021 14:13:38 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 04F3C6B006E; Thu, 18 Feb 2021 14:13:38 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id EA6C86B0070; Thu, 18 Feb 2021 14:13:37 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0144.hostedemail.com [216.40.44.144]) by kanga.kvack.org (Postfix) with ESMTP id D43206B006C for ; Thu, 18 Feb 2021 14:13:37 -0500 (EST) Received: from smtpin01.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 85BBC180AC46A for ; Thu, 18 Feb 2021 19:13:37 +0000 (UTC) X-FDA: 77832337674.01.7E0F0F5 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf24.hostedemail.com (Postfix) with ESMTP id A6F8AA0009DE for ; Thu, 18 Feb 2021 19:13:33 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1613675615; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=coKwHmBVYiHs8qdOkruTnwD9yAp//Y7kxMvu4I7zdqY=; b=RrzzDoFBHuoESeKLGhbYtUZ76hX2PS4zXWM0yFtA3ev3pd8bUmOqRWsEsvLz8Mp9+C2vOZ xuTMlVt1KK6DqHqEnjE6lgIUxNCAJI/xTnFu/bH3lYcLO5H2mpP9smtIWKCM6xxRS1+HiW NVPdOvXpq/zekqTWu5tRnseE0G3iFtE= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id BF44EAED2; Thu, 18 Feb 2021 19:13:35 +0000 (UTC) Date: Thu, 18 Feb 2021 20:13:34 +0100 From: Michal Hocko To: Tim Chen Cc: Andrew Morton , Johannes Weiner , Vladimir Davydov , Dave Hansen , Ying Huang , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 1/3] mm: Fix dropped memcg from mem cgroup soft limit tree Message-ID: References: <8d35206601ccf0e1fe021d24405b2a0c2f4e052f.1613584277.git.tim.c.chen@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <8d35206601ccf0e1fe021d24405b2a0c2f4e052f.1613584277.git.tim.c.chen@linux.intel.com> X-Stat-Signature: tkpkr4ubu3nuahpukd4ckcqbtzidiu6u X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: A6F8AA0009DE Received-SPF: none (suse.com>: No applicable sender policy available) receiver=imf24; identity=mailfrom; envelope-from=""; helo=mx2.suse.de; client-ip=195.135.220.15 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1613675613-683749 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: On Wed 17-02-21 12:41:34, Tim Chen wrote: > During soft limit memory reclaim, we will temporarily remove the target > mem cgroup from the cgroup soft limit tree. We then perform memory > reclaim, update the memory usage excess count and re-insert the mem > cgroup back into the mem cgroup soft limit tree according to the new > memory usage excess count. > > However, when memory reclaim failed for a maximum number of attempts > and we bail out of the reclaim loop, we forgot to put the target mem > cgroup chosen for next reclaim back to the soft limit tree. This prevented > pages in the mem cgroup from being reclaimed in the future even though > the mem cgroup exceeded its soft limit. Fix the logic and put the mem > cgroup back on the tree when page reclaim failed for the mem cgroup. > > Reviewed-by: Ying Huang > Signed-off-by: Tim Chen Fixes: 4e41695356fb ("memory controller: soft limit reclaim on contention") Acked-by: Michal Hocko Thanks! > --- > mm/memcontrol.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index ed5cc78a8dbf..a51bf90732cb 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -3505,8 +3505,12 @@ unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order, > loop > MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS)) > break; > } while (!nr_reclaimed); > - if (next_mz) > + if (next_mz) { > + spin_lock_irq(&mctz->lock); > + __mem_cgroup_insert_exceeded(next_mz, mctz, excess); > + spin_unlock_irq(&mctz->lock); > css_put(&next_mz->memcg->css); > + } > return nr_reclaimed; > } > > -- > 2.20.1 -- Michal Hocko SUSE Labs