From patchwork Thu May 11 05:22:30 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "zhaoyang.huang" X-Patchwork-Id: 92362 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b0ea:0:b0:3b6:4342:cba0 with SMTP id b10csp4128410vqo; Wed, 10 May 2023 22:36:55 -0700 (PDT) X-Google-Smtp-Source: ACHHUZ5Jo6y4kvkIxX8QYhQm+zaM8eM913QJS9tDSCH2jmWbVdwsMQ9Qob5YmdCX/dJ93nYlGdWc X-Received: by 2002:a17:90a:7801:b0:24e:16aa:48 with SMTP id w1-20020a17090a780100b0024e16aa0048mr19788217pjk.15.1683783415575; Wed, 10 May 2023 22:36:55 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1683783415; cv=none; d=google.com; s=arc-20160816; b=f/zzVCb2ZoWhn9QpiD04lJe76We08gn2EatDTiGTHf22YrE31/UfhMvcOusAeJiJBm Wkg4JIMre6PIOWAXCuFRmL5fZmy2dMLUhe8ZzENpoKF88OBYEAGUT8R6UUsl4wp9UxYW mH7EYSXNChU7jYNMgiMFQjwRE8aDllQUyyE0eBnoKmiush3wrUAYN6zvnszuxJZvjV/C lCv2l66SY0B60E+SV2EZ0NHUyjGBtaYnQEe2Ta/kyiQfpzrFnn/F8Wv+vQjHTfbl83XU ziVVnzE/sXif4WGkOd68gntzJfYAjWehzX46cWyrmFE/34IC/863lLWuZFTwvd47Ppeh Scmw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:mime-version:message-id:date:subject:to:from; bh=LdsTI0B0sR0dWH8uXtsF4wlOe+BmEUWOB5z9Wpzc034=; b=xledRl1srDfz9yg3WYcTpG6lP/W8HShS1thPscld3oEm5v1We0XNWKyFBS7NRVQnGW TTaMTm9VyZYcxCvYVmHFhrDhQbjawuYlxThIX/FInPh0tXb8prn1mZfMigIB/6nPAq5Z jLx78CuzH0+hbDA7NjJShwy3YRFtIKXNo9uW62px6D0e82NJSo7COjfQoQdnN37zRsIJ B755+rqIygY3Yp+WtOYXHnxgP5Em5Z4o234w+tVc3oUa2HgnIMLmKGt4Zqvx0vBuMDT5 k22hUpy7WbRXdLMM5ueoY2gkU7ejCBC89Grip78vVI/tae0w8EkjvvxrBKvZBH0f0R/z cbLA== 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 Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id a28-20020a637f1c000000b0052c4e3dafa4si5670618pgd.395.2023.05.10.22.36.38; Wed, 10 May 2023 22:36:55 -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 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237068AbjEKFYg (ORCPT + 99 others); Thu, 11 May 2023 01:24:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44640 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236939AbjEKFYb (ORCPT ); Thu, 11 May 2023 01:24:31 -0400 Received: from SHSQR01.spreadtrum.com (unknown [222.66.158.135]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C6A4E61A2 for ; Wed, 10 May 2023 22:23:57 -0700 (PDT) Received: from SHSend.spreadtrum.com (bjmbx01.spreadtrum.com [10.0.64.7]) by SHSQR01.spreadtrum.com with ESMTP id 34B5MmNo050137; Thu, 11 May 2023 13:22:48 +0800 (+08) (envelope-from zhaoyang.huang@unisoc.com) Received: from bj03382pcu.spreadtrum.com (10.0.74.65) by BJMBX01.spreadtrum.com (10.0.64.7) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Thu, 11 May 2023 13:22:44 +0800 From: "zhaoyang.huang" To: Andrew Morton , Roman Gushchin , Minchan Kim , Roman Gushchin , Joonsoo Kim , , , Zhaoyang Huang , Subject: [PATCHv5] mm: optimization on page allocation when CMA enabled Date: Thu, 11 May 2023 13:22:30 +0800 Message-ID: <1683782550-25799-1-git-send-email-zhaoyang.huang@unisoc.com> X-Mailer: git-send-email 1.9.1 MIME-Version: 1.0 X-Originating-IP: [10.0.74.65] X-ClientProxiedBy: SHCAS03.spreadtrum.com (10.0.1.207) To BJMBX01.spreadtrum.com (10.0.64.7) X-MAIL: SHSQR01.spreadtrum.com 34B5MmNo050137 X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,SPF_HELO_NONE, SPF_PASS,T_SCC_BODY_TEXT_LINE 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?1765574878820607504?= X-GMAIL-MSGID: =?utf-8?q?1765574878820607504?= From: Zhaoyang Huang Let us look at the timeline of scenarios below with WMARK_LOW=25MB WMARK_MIN=5MB (managed pages 1.9GB). We can find that CMA begin to be used until 'C' under the method of 'fixed 2 times of free cma over free pages' which could have the scenario 'A' and 'B' into a fault state, that is, free UNMOVABLE & RECLAIMABLE pages is lower than corresponding watermark without reclaiming which should be deemed as against current memory policy. This commit try to solve this by checking zone_watermark_ok again with removing CMA pages which could lead to a proper time point of CMA's utilization. -- Free_pages | | -- WMARK_LOW | -- Free_CMA | | --- Free_CMA/Free_pages(MB) A(12/30) --> B(12/25) --> C(12/20) fixed 1/2 ratio N N Y this commit Y Y Y Signed-off-by: Zhaoyang Huang --- v2: do proportion check when zone_watermark_ok, update commit message v3: update coding style and simplify the logic when zone_watermark_ok v4: code update according to Roman's suggest v5: update commit message --- --- mm/page_alloc.c | 44 ++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 40 insertions(+), 4 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 0745aed..4719800 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3071,6 +3071,43 @@ static bool unreserve_highatomic_pageblock(const struct alloc_context *ac, } +#ifdef CONFIG_CMA +/* + * GFP_MOVABLE allocation could drain UNMOVABLE & RECLAIMABLE page blocks via + * the help of CMA which makes GFP_KERNEL failed. Checking if zone_watermark_ok + * again without ALLOC_CMA to see if to use CMA first. + */ +static bool use_cma_first(struct zone *zone, unsigned int order, unsigned int alloc_flags) +{ + unsigned long watermark; + bool cma_first = false; + + watermark = wmark_pages(zone, alloc_flags & ALLOC_WMARK_MASK); + /* check if GFP_MOVABLE pass previous zone_watermark_ok via the help of CMA */ + if (zone_watermark_ok(zone, order, watermark, 0, alloc_flags & (~ALLOC_CMA))) { + /* + * Balance movable allocations between regular and CMA areas by + * allocating from CMA when over half of the zone's free memory + * is in the CMA area. + */ + cma_first = (zone_page_state(zone, NR_FREE_CMA_PAGES) > + zone_page_state(zone, NR_FREE_PAGES) / 2); + } else { + /* + * watermark failed means UNMOVABLE & RECLAIMBLE is not enough + * now, we should use cma first to keep them stay around the + * corresponding watermark + */ + cma_first = true; + } + return cma_first; +} +#else +static bool use_cma_first(struct zone *zone, unsigned int order, unsigned int alloc_flags) +{ + return false; +} +#endif /* * Do the hard work of removing an element from the buddy allocator. * Call me with the zone->lock already held. @@ -3084,12 +3121,11 @@ static bool unreserve_highatomic_pageblock(const struct alloc_context *ac, if (IS_ENABLED(CONFIG_CMA)) { /* * Balance movable allocations between regular and CMA areas by - * allocating from CMA when over half of the zone's free memory - * is in the CMA area. + * allocating from CMA base on judging zone_watermark_ok again + * to see if the latest check got pass via the help of CMA */ if (alloc_flags & ALLOC_CMA && - zone_page_state(zone, NR_FREE_CMA_PAGES) > - zone_page_state(zone, NR_FREE_PAGES) / 2) { + use_cma_first(zone, order, alloc_flags)) { page = __rmqueue_cma_fallback(zone, order); if (page) return page;