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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 16EA3C2D0CE for ; Wed, 22 Jan 2020 01:17:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E81D124656 for ; Wed, 22 Jan 2020 01:17:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729148AbgAVBRU (ORCPT ); Tue, 21 Jan 2020 20:17:20 -0500 Received: from mga06.intel.com ([134.134.136.31]:24737 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729113AbgAVBRQ (ORCPT ); Tue, 21 Jan 2020 20:17:16 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga104.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 21 Jan 2020 17:17:16 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,347,1574150400"; d="scan'208";a="244885539" Received: from richard.sh.intel.com (HELO localhost) ([10.239.159.54]) by orsmga002.jf.intel.com with ESMTP; 21 Jan 2020 17:17:14 -0800 From: Wei Yang To: akpm@linux-foundation.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, mhocko@suse.com, yang.shi@linux.alibaba.com, rientjes@google.com, Wei Yang Subject: [Patch v2 4/4] mm/migrate.c: handle same node and add failure in the same way Date: Wed, 22 Jan 2020 09:16:47 +0800 Message-Id: <20200122011647.13636-5-richardw.yang@linux.intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200122011647.13636-1-richardw.yang@linux.intel.com> References: <20200122011647.13636-1-richardw.yang@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When page is not queued for migration, there are two possible cases: * page already on the target node * failed to add to migration queue Current code handle them differently, this leads to a behavior inconsistency. Usually for each page's status, we just do store for once. While for the page already on the target node, we might store the node information for twice: * once when we found the page is on the target node * second when moving the pages to target node successfully after above action The reason is even we don't add the page to pagelist, but store_status() does store in a range which still contains the page. This patch handles these two cases in the same way to reduce this inconsistency and also make the code a little easier to read. Signed-off-by: Wei Yang Acked-by: Michal Hocko --- mm/migrate.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/mm/migrate.c b/mm/migrate.c index 80d2bba57265..591f2e5caed6 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -1654,18 +1654,18 @@ static int do_pages_move(struct mm_struct *mm, nodemask_t task_nodes, err = add_page_for_migration(mm, addr, current_node, &pagelist, flags & MPOL_MF_MOVE_ALL); - if (!err) { - /* The page is already on the target node */ - err = store_status(status, i, current_node, 1); - if (err) - goto out_flush; - continue; - } else if (err > 0) { + if (err > 0) { /* The page is successfully queued for migration */ continue; } - err = store_status(status, i, err, 1); + /* + * Two possible cases for err here: + * == 0: page is already on the target node, then store + * current_node to status + * < 0: failed to add page to list, then store err to status + */ + err = store_status(status, i, err ? : current_node, 1); if (err) goto out_flush; -- 2.17.1