From patchwork Thu Apr 15 10:35:38 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oscar Salvador X-Patchwork-Id: 12205047 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,URIBL_BLOCKED,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 296C1C43461 for ; Thu, 15 Apr 2021 10:35:53 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id CE6DF61152 for ; Thu, 15 Apr 2021 10:35:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CE6DF61152 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id B58656B006C; Thu, 15 Apr 2021 06:35:51 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B2E4C6B0070; Thu, 15 Apr 2021 06:35:51 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 959856B0071; Thu, 15 Apr 2021 06:35:51 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0135.hostedemail.com [216.40.44.135]) by kanga.kvack.org (Postfix) with ESMTP id 764566B006C for ; Thu, 15 Apr 2021 06:35:51 -0400 (EDT) Received: from smtpin20.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 35ECB180D870D for ; Thu, 15 Apr 2021 10:35:51 +0000 (UTC) X-FDA: 78034245702.20.270E805 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf02.hostedemail.com (Postfix) with ESMTP id D204940002D8 for ; Thu, 15 Apr 2021 10:35:33 +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 B94B8AF0D; Thu, 15 Apr 2021 10:35:49 +0000 (UTC) From: Oscar Salvador To: Andrew Morton Cc: Mike Kravetz , Vlastimil Babka , David Hildenbrand , Michal Hocko , Muchun Song , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Oscar Salvador , Michal Hocko Subject: [PATCH v8 1/7] mm,page_alloc: Bail out earlier on -ENOMEM in alloc_contig_migrate_range Date: Thu, 15 Apr 2021 12:35:38 +0200 Message-Id: <20210415103544.6791-2-osalvador@suse.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20210415103544.6791-1-osalvador@suse.de> References: <20210415103544.6791-1-osalvador@suse.de> MIME-Version: 1.0 X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: D204940002D8 X-Stat-Signature: 5noj7hjs6ee57baf9jg6neutbs989sdw Received-SPF: none (suse.de>: No applicable sender policy available) receiver=imf02; identity=mailfrom; envelope-from=""; helo=mx2.suse.de; client-ip=195.135.220.15 X-HE-DKIM-Result: none/none X-HE-Tag: 1618482933-991213 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: Currently, __alloc_contig_migrate_range can generate -EINTR, -ENOMEM or -EBUSY, and report them down the chain. The problem is that when migrate_pages() reports -ENOMEM, we keep going till we exhaust all the try-attempts (5 at the moment) instead of bailing out. migrate_pages() bails out right away on -ENOMEM because it is considered a fatal error. Do the same here instead of keep going and retrying. Note that this is not fixing a real issue, just a cosmetic change. Although we can save some cycles by backing off ealier Signed-off-by: Oscar Salvador Acked-by: Vlastimil Babka Reviewed-by: David Hildenbrand Acked-by: Michal Hocko Acked-by: Mike Kravetz --- mm/page_alloc.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 1c67c99603a3..689454692de1 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -8697,7 +8697,7 @@ static int __alloc_contig_migrate_range(struct compact_control *cc, } tries = 0; } else if (++tries == 5) { - ret = ret < 0 ? ret : -EBUSY; + ret = -EBUSY; break; } @@ -8707,6 +8707,13 @@ static int __alloc_contig_migrate_range(struct compact_control *cc, ret = migrate_pages(&cc->migratepages, alloc_migration_target, NULL, (unsigned long)&mtc, cc->mode, MR_CONTIG_RANGE); + + /* + * On -ENOMEM, migrate_pages() bails out right away. It is pointless + * to retry again over this error, so do the same here. + */ + if (ret == -ENOMEM) + break; } lru_cache_enable();