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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 75304C07E96 for ; Thu, 15 Jul 2021 05:52:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5888961358 for ; Thu, 15 Jul 2021 05:52:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240134AbhGOFzg (ORCPT ); Thu, 15 Jul 2021 01:55:36 -0400 Received: from mga02.intel.com ([134.134.136.20]:22887 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240092AbhGOFzc (ORCPT ); Thu, 15 Jul 2021 01:55:32 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10045"; a="197661970" X-IronPort-AV: E=Sophos;i="5.84,240,1620716400"; d="scan'208";a="197661970" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Jul 2021 22:52:39 -0700 X-IronPort-AV: E=Sophos;i="5.84,240,1620716400"; d="scan'208";a="505591649" Received: from yhuang6-mobl1.sh.intel.com ([10.238.6.138]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Jul 2021 22:52:36 -0700 From: Huang Ying To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Dave Hansen , "Huang, Ying" , Yang Shi , Yang Shi , Michal Hocko , Wei Xu , osalvador , Zi Yan , David Rientjes , Dan Williams , David Hildenbrand Subject: [PATCH -V10 8/9] mm/vmscan: never demote for memcg reclaim Date: Thu, 15 Jul 2021 13:51:44 +0800 Message-Id: <20210715055145.195411-9-ying.huang@intel.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210715055145.195411-1-ying.huang@intel.com> References: <20210715055145.195411-1-ying.huang@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dave Hansen Global reclaim aims to reduce the amount of memory used on a given node or set of nodes. Migrating pages to another node serves this purpose. memcg reclaim is different. Its goal is to reduce the total memory consumption of the entire memcg, across all nodes. Migration does not assist memcg reclaim because it just moves page contents between nodes rather than actually reducing memory consumption. Signed-off-by: Dave Hansen Signed-off-by: "Huang, Ying" Suggested-by: Yang Shi Reviewed-by: Yang Shi Cc: Michal Hocko Cc: Wei Xu Cc: osalvador Cc: Zi Yan Cc: David Rientjes Cc: Dan Williams Cc: David Hildenbrand -- changes from 20210618: * Avoid to scan anon lists for demotion for cgroup reclaim. --- mm/vmscan.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 0f9be998230f..b697f1a6108c 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -521,8 +521,13 @@ static long add_nr_deferred(long nr, struct shrinker *shrinker, static bool can_demote_anon_pages(int nid, struct scan_control *sc) { - if (sc && sc->no_demotion) - return false; + if (sc) { + if (sc->no_demotion) + return false; + /* It is pointless to do demotion in memcg reclaim */ + if (cgroup_reclaim(sc)) + return false; + } if (next_demotion_node(nid) == NUMA_NO_NODE) return false; -- 2.30.2