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=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 BF94FC433E0 for ; Fri, 29 Jan 2021 15:41:01 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 4D88F64DE9 for ; Fri, 29 Jan 2021 15:41:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4D88F64DE9 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.cz Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 415A66B006C; Fri, 29 Jan 2021 10:41:00 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 39E786B0070; Fri, 29 Jan 2021 10:41:00 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 23EBA6B0071; Fri, 29 Jan 2021 10:41:00 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0066.hostedemail.com [216.40.44.66]) by kanga.kvack.org (Postfix) with ESMTP id 0ABAA6B006C for ; Fri, 29 Jan 2021 10:41:00 -0500 (EST) Received: from smtpin20.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id BA313180AD81A for ; Fri, 29 Jan 2021 15:40:59 +0000 (UTC) X-FDA: 77759225838.20.rule84_4d16cbb275a9 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin20.hostedemail.com (Postfix) with ESMTP id 83C9B180C07AB for ; Fri, 29 Jan 2021 15:40:59 +0000 (UTC) X-HE-Tag: rule84_4d16cbb275a9 X-Filterd-Recvd-Size: 2490 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf36.hostedemail.com (Postfix) with ESMTP for ; Fri, 29 Jan 2021 15:40:58 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id C92A3ABDA; Fri, 29 Jan 2021 15:40:57 +0000 (UTC) Subject: Re: [v5 PATCH 09/11] mm: vmscan: don't need allocate shrinker->nr_deferred for memcg aware shrinkers To: Yang Shi , guro@fb.com, ktkhai@virtuozzo.com, shakeelb@google.com, david@fromorbit.com, hannes@cmpxchg.org, mhocko@suse.com, akpm@linux-foundation.org Cc: linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org References: <20210127233345.339910-1-shy828301@gmail.com> <20210127233345.339910-10-shy828301@gmail.com> From: Vlastimil Babka Message-ID: Date: Fri, 29 Jan 2021 16:40:57 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.6.1 MIME-Version: 1.0 In-Reply-To: <20210127233345.339910-10-shy828301@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit 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 1/28/21 12:33 AM, Yang Shi wrote: > Now nr_deferred is available on per memcg level for memcg aware shrinkers, so don't need > allocate shrinker->nr_deferred for such shrinkers anymore. > > The prealloc_memcg_shrinker() would return -ENOSYS if !CONFIG_MEMCG or memcg is disabled > by kernel command line, then shrinker's SHRINKER_MEMCG_AWARE flag would be cleared. > This makes the implementation of this patch simpler. > > Signed-off-by: Yang Shi Acked-by: Vlastimil Babka > @@ -525,8 +528,20 @@ unsigned long lruvec_lru_size(struct lruvec *lruvec, enum lru_list lru, int zone > */ > int prealloc_shrinker(struct shrinker *shrinker) > { > - unsigned int size = sizeof(*shrinker->nr_deferred); > + unsigned int size; > + int err; > + > + if (shrinker->flags & SHRINKER_MEMCG_AWARE) { > + err = prealloc_memcg_shrinker(shrinker); > + if (!err) > + return 0; Nit: this err == 0 case is covered below: > + if (err != -ENOSYS) > + return err; > + > + shrinker->flags &= ~SHRINKER_MEMCG_AWARE; > + } > > + size = sizeof(*shrinker->nr_deferred); > if (shrinker->flags & SHRINKER_NUMA_AWARE) > size *= nr_node_ids; >