From patchwork Wed May 5 01:36:39 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 12238891 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=unavailable 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 89534C433ED for ; Wed, 5 May 2021 01:36:42 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 3A4A3611AB for ; Wed, 5 May 2021 01:36:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3A4A3611AB Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id C92DA8D005A; Tue, 4 May 2021 21:36:41 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C687B8D003B; Tue, 4 May 2021 21:36:41 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B31418D005A; Tue, 4 May 2021 21:36:41 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0048.hostedemail.com [216.40.44.48]) by kanga.kvack.org (Postfix) with ESMTP id 93B718D003B for ; Tue, 4 May 2021 21:36:41 -0400 (EDT) Received: from smtpin16.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 5AAEF181AF5C2 for ; Wed, 5 May 2021 01:36:41 +0000 (UTC) X-FDA: 78105463002.16.E9B9E38 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf29.hostedemail.com (Postfix) with ESMTP id AC163132 for ; Wed, 5 May 2021 01:36:35 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id CA9B661029; Wed, 5 May 2021 01:36:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1620178600; bh=eGFXdW984VlbspGGB3ahtI20bCqkiC3nJOYik2NDNXc=; h=Date:From:To:Subject:In-Reply-To:From; b=C+SHQqjT929zZpcy0pS9ru69foCNJeYdcKzsXbAAbm0ijLfyJ7aRUrwsyoXUEQmI3 9XocBCnIMlT9PAhNeOENr7EqnqqHF9w1bAInDPR9M7xK7EfJhr2lnJU2N7tchFDeqx flCb5+PDp3ro9a1IP7TdbUTr0z/T6P8uY0QQzjJA= Date: Tue, 04 May 2021 18:36:39 -0700 From: Andrew Morton To: akpm@linux-foundation.org, david@fromorbit.com, guro@fb.com, hannes@cmpxchg.org, ktkhai@virtuozzo.com, linux-mm@kvack.org, mhocko@suse.com, mm-commits@vger.kernel.org, shakeelb@google.com, shy828301@gmail.com, torvalds@linux-foundation.org, vbabka@suse.cz Subject: [patch 072/143] mm: vmscan: don't need allocate shrinker->nr_deferred for memcg aware shrinkers Message-ID: <20210505013639.aAAblJEiX%akpm@linux-foundation.org> In-Reply-To: <20210504183219.a3cc46aee4013d77402276c5@linux-foundation.org> User-Agent: s-nail v14.8.16 Authentication-Results: imf29.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=C+SHQqjT; dmarc=none; spf=pass (imf29.hostedemail.com: domain of akpm@linux-foundation.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org X-Rspamd-Server: rspam03 X-Stat-Signature: ndd8oxc5sdagb3wcefxckwewwomhg63y X-Rspamd-Queue-Id: AC163132 Received-SPF: none (linux-foundation.org>: No applicable sender policy available) receiver=imf29; identity=mailfrom; envelope-from=""; helo=mail.kernel.org; client-ip=198.145.29.99 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1620178595-65102 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: From: Yang Shi Subject: mm: vmscan: don't need allocate shrinker->nr_deferred for memcg aware shrinkers 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. Link: https://lkml.kernel.org/r/20210311190845.9708-12-shy828301@gmail.com Signed-off-by: Yang Shi Acked-by: Vlastimil Babka Reviewed-by: Kirill Tkhai Acked-by: Roman Gushchin Reviewed-by: Shakeel Butt Cc: Dave Chinner Cc: Johannes Weiner Cc: Michal Hocko Signed-off-by: Andrew Morton --- mm/vmscan.c | 31 ++++++++++++++++--------------- 1 file changed, 16 insertions(+), 15 deletions(-) --- a/mm/vmscan.c~mm-vmscan-dont-need-allocate-shrinker-nr_deferred-for-memcg-aware-shrinkers +++ a/mm/vmscan.c @@ -346,6 +346,9 @@ static int prealloc_memcg_shrinker(struc { int id, ret = -ENOMEM; + if (mem_cgroup_disabled()) + return -ENOSYS; + down_write(&shrinker_rwsem); /* This may call shrinker, so it must use down_read_trylock() */ id = idr_alloc(&shrinker_idr, shrinker, 0, 0, GFP_KERNEL); @@ -425,7 +428,7 @@ static bool writeback_throttling_sane(st #else static int prealloc_memcg_shrinker(struct shrinker *shrinker) { - return 0; + return -ENOSYS; } static void unregister_memcg_shrinker(struct shrinker *shrinker) @@ -537,8 +540,18 @@ static unsigned long lruvec_lru_size(str */ 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 != -ENOSYS) + return err; + shrinker->flags &= ~SHRINKER_MEMCG_AWARE; + } + + size = sizeof(*shrinker->nr_deferred); if (shrinker->flags & SHRINKER_NUMA_AWARE) size *= nr_node_ids; @@ -546,28 +559,16 @@ int prealloc_shrinker(struct shrinker *s if (!shrinker->nr_deferred) return -ENOMEM; - if (shrinker->flags & SHRINKER_MEMCG_AWARE) { - if (prealloc_memcg_shrinker(shrinker)) - goto free_deferred; - } - return 0; - -free_deferred: - kfree(shrinker->nr_deferred); - shrinker->nr_deferred = NULL; - return -ENOMEM; } void free_prealloced_shrinker(struct shrinker *shrinker) { - if (!shrinker->nr_deferred) - return; - if (shrinker->flags & SHRINKER_MEMCG_AWARE) { down_write(&shrinker_rwsem); unregister_memcg_shrinker(shrinker); up_write(&shrinker_rwsem); + return; } kfree(shrinker->nr_deferred);