From patchwork Wed Jun 14 08:40:20 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Baolin Wang X-Patchwork-Id: 107827 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:994d:0:b0:3d9:f83d:47d9 with SMTP id k13csp1105277vqr; Wed, 14 Jun 2023 02:21:28 -0700 (PDT) X-Google-Smtp-Source: ACHHUZ6ngDX1CE4lqmBczAPflH9NROKzXT84UvjDFS5tQ5mlYpSWsgz0gkPILM7u7hgpltgFWLWu X-Received: by 2002:a17:907:98d:b0:957:1df0:9cbf with SMTP id bf13-20020a170907098d00b009571df09cbfmr13574081ejc.19.1686734488306; Wed, 14 Jun 2023 02:21:28 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1686734488; cv=none; d=google.com; s=arc-20160816; b=d9h8rS24XF2a09HrfCWR/AefpvP2VswXvX4h/6l4rXfte4QdS51+pT3l2uz314oPIK l5Kf/0kZt0S1xq1vf5F5Hs+3kdeBJm35tXJceeRubAK9y7f86YxsSpCotdJP2M8zMMcV YIX0tpj74Q+Ww09NCM7BWFYMqtYZWSiV1yL7GnzuwKhYLQixzgVqxlG8hhYZyHzaLMfQ w5jB9fw5wBH8hqjaCGMWrsRlJrqYf9aBriTrakmswEWFEdY/zC/ShOjtKnr9duNJhVzJ Bf+ELLJR7+sUaF8axUbjgwwsZnkGnbRsGdJJQq9S/Npj2jTX2WwXvVeooB4jju7WaZhH f9+g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :message-id:date:subject:cc:to:from; bh=anwy2nJenaZMEVPT17e8ThGgvVIZ680A3/ngu4eVbmA=; b=MwXirqLrf156ejNz7WN228yjSFtpAeKO3YmioWWT2hyG8qkIgyFILVALsqbY/A2AHe lD/rRB3zxyMUQKgMzB6hCRVRCYWyvn6FgqwUDLxNG8D3omsEBD7Hp/NZAICCP8jghZut MMpXO5mILovJYdle23CKnzBiOWJsl3UVhQxQ879xfRp9sn4VClfpE6ePJVa82QCuWkyX EvDr7wrY/D4ZgVhl9GI41wNF9/IBW4f5a4VjHq0NsRFg3LDIMgFfKtduJkxPdj21D4Ec VihS5HKfi/refbhXSC4jRmtFqJLpIFt+y4C+wnflHYsdmDUxV0c6UM0KdMWto7ie2LZp WFwg== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=alibaba.com Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id n7-20020a170906688700b00950ea4cbd16si7724249ejr.271.2023.06.14.02.20.22; Wed, 14 Jun 2023 02:21:28 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=alibaba.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243696AbjFNIkh (ORCPT + 99 others); Wed, 14 Jun 2023 04:40:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33442 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243683AbjFNIkc (ORCPT ); Wed, 14 Jun 2023 04:40:32 -0400 Received: from out30-110.freemail.mail.aliyun.com (out30-110.freemail.mail.aliyun.com [115.124.30.110]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4E3DC1BC6 for ; Wed, 14 Jun 2023 01:40:31 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R121e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046049;MF=baolin.wang@linux.alibaba.com;NM=1;PH=DS;RN=8;SR=0;TI=SMTPD_---0Vl5okOP_1686732027; Received: from localhost(mailfrom:baolin.wang@linux.alibaba.com fp:SMTPD_---0Vl5okOP_1686732027) by smtp.aliyun-inc.com; Wed, 14 Jun 2023 16:40:28 +0800 From: Baolin Wang To: akpm@linux-foundation.org Cc: mgorman@techsingularity.net, vbabka@suse.cz, david@redhat.com, ying.huang@intel.com, baolin.wang@linux.alibaba.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v3] mm: compaction: skip memory hole rapidly when isolating migratable pages Date: Wed, 14 Jun 2023 16:40:20 +0800 Message-Id: <75b4c8ca36bf44ad8c42bf0685ac19d272e426ec.1686705221.git.baolin.wang@linux.alibaba.com> X-Mailer: git-send-email 2.27.0 MIME-Version: 1.0 X-Spam-Status: No, score=-9.9 required=5.0 tests=BAYES_00, ENV_AND_HDR_SPF_MATCH,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS, T_SCC_BODY_TEXT_LINE,UNPARSEABLE_RELAY,USER_IN_DEF_SPF_WL autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1768669303048525718?= X-GMAIL-MSGID: =?utf-8?q?1768669303048525718?= On some machines, the normal zone can have a large memory hole like below memory layout, and we can see the range from 0x100000000 to 0x1800000000 is a hole. So when isolating some migratable pages, the scanner can meet the hole and it will take more time to skip the large hole. From my measurement, I can see the isolation scanner will take 80us ~ 100us to skip the large hole [0x100000000 - 0x1800000000]. So adding a new helper to fast search next online memory section to skip the large hole can help to find next suitable pageblock efficiently. With this patch, I can see the large hole scanning only takes < 1us. [ 0.000000] Zone ranges: [ 0.000000] DMA [mem 0x0000000040000000-0x00000000ffffffff] [ 0.000000] DMA32 empty [ 0.000000] Normal [mem 0x0000000100000000-0x0000001fa7ffffff] [ 0.000000] Movable zone start for each node [ 0.000000] Early memory node ranges [ 0.000000] node 0: [mem 0x0000000040000000-0x0000000fffffffff] [ 0.000000] node 0: [mem 0x0000001800000000-0x0000001fa3c7ffff] [ 0.000000] node 0: [mem 0x0000001fa3c80000-0x0000001fa3ffffff] [ 0.000000] node 0: [mem 0x0000001fa4000000-0x0000001fa402ffff] [ 0.000000] node 0: [mem 0x0000001fa4030000-0x0000001fa40effff] [ 0.000000] node 0: [mem 0x0000001fa40f0000-0x0000001fa73cffff] [ 0.000000] node 0: [mem 0x0000001fa73d0000-0x0000001fa745ffff] [ 0.000000] node 0: [mem 0x0000001fa7460000-0x0000001fa746ffff] [ 0.000000] node 0: [mem 0x0000001fa7470000-0x0000001fa758ffff] [ 0.000000] node 0: [mem 0x0000001fa7590000-0x0000001fa7ffffff] Suggested-by: David Hildenbrand Signed-off-by: Baolin Wang Acked-by: David Hildenbrand Acked-by: "Huang, Ying" --- Changes from v2: - Simplify the function suggested by David. - Collect acked tag from David and Ying. Thanks. Changes from v1: - Fix building errors if CONFIG_SPARSEMEM is not selected. - Use NR_MEM_SECTIONS instead of '-1' per Huang Ying. --- mm/compaction.c | 35 ++++++++++++++++++++++++++++++++++- 1 file changed, 34 insertions(+), 1 deletion(-) diff --git a/mm/compaction.c b/mm/compaction.c index 3398ef3a55fe..0b2680b075fd 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -229,6 +229,33 @@ static void reset_cached_positions(struct zone *zone) pageblock_start_pfn(zone_end_pfn(zone) - 1); } +#ifdef CONFIG_SPARSEMEM +/* + * If the PFN falls into an offline section, return the start PFN of the + * next online section. If the PFN falls into an online section or if + * there is no next online section, return 0. + */ +static unsigned long skip_offline_sections(unsigned long start_pfn) +{ + unsigned long start_nr = pfn_to_section_nr(start_pfn); + + if (online_section_nr(start_nr)) + return 0; + + while (++start_nr <= __highest_present_section_nr) { + if (online_section_nr(start_nr)) + return section_nr_to_pfn(start_nr); + } + + return 0; +} +#else +static unsigned long skip_offline_sections(unsigned long start_pfn) +{ + return 0; +} +#endif + /* * Compound pages of >= pageblock_order should consistently be skipped until * released. It is always pointless to compact pages of such order (if they are @@ -1991,8 +2018,14 @@ static isolate_migrate_t isolate_migratepages(struct compact_control *cc) page = pageblock_pfn_to_page(block_start_pfn, block_end_pfn, cc->zone); - if (!page) + if (!page) { + unsigned long next_pfn; + + next_pfn = skip_offline_sections(block_start_pfn); + if (next_pfn) + block_end_pfn = next_pfn; continue; + } /* * If isolation recently failed, do not retry. Only check the