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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 1D932C43603 for ; Thu, 5 Dec 2019 08:23:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D235A20707 for ; Thu, 5 Dec 2019 08:23:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726421AbfLEIXz (ORCPT ); Thu, 5 Dec 2019 03:23:55 -0500 Received: from relay.sw.ru ([185.231.240.75]:43666 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725974AbfLEIXz (ORCPT ); Thu, 5 Dec 2019 03:23:55 -0500 Received: from dhcp-172-16-24-104.sw.ru ([172.16.24.104]) by relay.sw.ru with esmtp (Exim 4.92.3) (envelope-from ) id 1icmQ5-00057R-Aj; Thu, 05 Dec 2019 11:23:29 +0300 Subject: Re: [PATCH] mm: vmscan: protect shrinker idr replace with CONFIG_MEMCG To: Yang Shi , hannes@cmpxchg.org, mhocko@suse.com, shakeelb@google.com, guro@fb.com, akpm@linux-foundation.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <1575486978-45249-1-git-send-email-yang.shi@linux.alibaba.com> From: Kirill Tkhai Message-ID: Date: Thu, 5 Dec 2019 11:23:28 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <1575486978-45249-1-git-send-email-yang.shi@linux.alibaba.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04.12.2019 22:16, Yang Shi wrote: > Since commit 0a432dcbeb32edcd211a5d8f7847d0da7642a8b4 ("mm: shrinker: > make shrinker not depend on memcg kmem"), shrinkers' idr is protected by > CONFIG_MEMCG instead of CONFIG_MEMCG_KMEM, so it makes no sense to > protect shrinker idr replace with CONFIG_MEMCG_KMEM. > > Cc: Kirill Tkhai > Cc: Johannes Weiner > Cc: Michal Hocko > Cc: Shakeel Butt > Cc: Roman Gushchin > Signed-off-by: Yang Shi It looks like that in CONFIG_SLOB case we do not even call some shrinkers for subordinate mem cgroups (i.e., we don't call deferred_split_shrinker), since they never become completely registered. Fixes: 0a432dcbeb32edcd211a5d8f7847d0da7642a8b4 ("mm: shrinker: make shrinker not depend on memcg kmem") Reviewed-by: Kirill Tkhai > --- > mm/vmscan.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/vmscan.c b/mm/vmscan.c > index ee4eecc..e7f10c4 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -422,7 +422,7 @@ void register_shrinker_prepared(struct shrinker *shrinker) > { > down_write(&shrinker_rwsem); > list_add_tail(&shrinker->list, &shrinker_list); > -#ifdef CONFIG_MEMCG_KMEM > +#ifdef CONFIG_MEMCG > if (shrinker->flags & SHRINKER_MEMCG_AWARE) > idr_replace(&shrinker_idr, shrinker, shrinker->id); > #endif >