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 6F033C35247 for ; Sun, 26 Jan 2020 10:27:30 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 31CD621556 for ; Sun, 26 Jan 2020 10:27:30 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 31CD621556 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 99B206B000A; Sun, 26 Jan 2020 05:27:26 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 925F46B000C; Sun, 26 Jan 2020 05:27:26 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7A2126B000D; Sun, 26 Jan 2020 05:27:26 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0254.hostedemail.com [216.40.44.254]) by kanga.kvack.org (Postfix) with ESMTP id 57E1E6B000A for ; Sun, 26 Jan 2020 05:27:26 -0500 (EST) Received: from smtpin27.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with SMTP id 05C93180AD804 for ; Sun, 26 Jan 2020 10:27:26 +0000 (UTC) X-FDA: 76419408492.27.walk36_40d695dec7214 X-HE-Tag: walk36_40d695dec7214 X-Filterd-Recvd-Size: 3239 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by imf11.hostedemail.com (Postfix) with ESMTP for ; Sun, 26 Jan 2020 10:27:25 +0000 (UTC) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga105.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 26 Jan 2020 02:27:25 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,365,1574150400"; d="scan'208";a="223002745" Received: from richard.sh.intel.com (HELO localhost) ([10.239.159.54]) by fmsmga008.fm.intel.com with ESMTP; 26 Jan 2020 02:27:23 -0800 From: Wei Yang To: akpm@linux-foundation.org Cc: mhocko@suse.com, yang.shi@linux.alibaba.com, rientjes@google.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Wei Yang Subject: [Patch v3 4/4] mm/migrate.c: handle same node and add failure in the same way Date: Sun, 26 Jan 2020 18:26:23 +0800 Message-Id: <20200126102623.9616-5-richardw.yang@linux.intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200126102623.9616-1-richardw.yang@linux.intel.com> References: <20200126102623.9616-1-richardw.yang@linux.intel.com> 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: 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 b123ced445b7..bb4f45b120fd 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -1665,18 +1665,18 @@ 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