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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 12E3DC4332F for ; Thu, 9 Nov 2023 08:30:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233497AbjKIIaz (ORCPT ); Thu, 9 Nov 2023 03:30:55 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33790 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231464AbjKIIay (ORCPT ); Thu, 9 Nov 2023 03:30:54 -0500 Received: from APC01-SG2-obe.outbound.protection.outlook.com (mail-sgaapc01on2123.outbound.protection.outlook.com [40.107.215.123]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B07282D54 for ; Thu, 9 Nov 2023 00:30:51 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=gtQ73zCQ55HeiZ4mY9X+9dgOM8/bz3AaqaYUdrC0k3xhHXHaucM1OmnSRcgsp0me+7gF0WqaUOWh0uE7HlfqnUEv4SjO+2GFyaqn55A8x8PuKXeg28FiI5kumnV9iyjgVxUDjDsaWldRKIlhdYAb+uX2jxZBr7ck36UU+eOnlr/o5T6UtbXk48jsmwD8HumhkopE0utUfHxcNIMAnENUtkeHmB0jBiErmCYAkjrgR/G6ZRk0JeZqvCMJeEteAh1saEmZH9ObZTFaa+/3STS2whThwss5IDFi9loZBw/kqyIToqWGYLpZfYcXgaccV7V119t3WUjw6B57r0YHjg26Og== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=wFDjdcPfWiClJnKHfdSrGhthGHGvJzva3CC7UeBiknk=; b=LldWLlWI7Uvoyym+xtsL0c5X6Vhdn5GnuR7bcEEDGBF+or0TVwbnI1v/sPgS2Olr3gHt/mZONOcZ8lz0bM5dAj10sR7tYaYIPD0lb5xqAQSxzzmgmz13sKsPhPnUYZ5OcyTrqvoB1z4jEYFU+xkT9nmT2qhpgEiFIxPsq5g6VM5Xd8DJrd2YZV7tKKRSb8cHtBOlLciNw7L1RU1GnQpDcPSnM+wNl2OkICd+BPQwr/bJyD43jz8HjW/ksnCnZq18HSuVuXQC3fGq/YEtIQ1+hyGdOBLGoEvVEiHAzkq7F7Ebffibf3qnxN6caZJAHbt9r6tCVHIWUJevqd8cWH4hCg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=vivo.com; dmarc=pass action=none header.from=vivo.com; dkim=pass header.d=vivo.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=vivo.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=wFDjdcPfWiClJnKHfdSrGhthGHGvJzva3CC7UeBiknk=; b=msndB3hQhPV19yA91FSsppSSlrrKuvIdLwehr0M1M7tBVM1T1tecqWh2bEoqjE/GITQw85XFLsf+WrV13X8q6Un7O8iLLQL6olxD0oNalOBFnJYUFc0ujM60ZUczFhN6ggJqxaJZ/kWozol7p2cI6VvzzqplUB2JZ4eQeAtLt1raWtR/PDGPus/Kp/GA3Tz9gIr3ngDhRZJLB0qpvx9P+Sbb94MZa8Q9qnlrXb2Qq+xXkKibQ6sJe0XTd0zmJyfaCDfpE9KW2Jbf5i3g0g1SyJ1ZcA1Yz+GJSZaQUkK7Xl5SR5pe6I3bWkO8Kcsb/l56notuoPjZSF+5eHEcD1zKSg== Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=vivo.com; Received: from JH0PR06MB6849.apcprd06.prod.outlook.com (2603:1096:990:47::12) by SEZPR06MB6871.apcprd06.prod.outlook.com (2603:1096:101:197::10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6954.28; Thu, 9 Nov 2023 08:30:45 +0000 Received: from JH0PR06MB6849.apcprd06.prod.outlook.com ([fe80::bdde:31ee:f13c:79fb]) by JH0PR06MB6849.apcprd06.prod.outlook.com ([fe80::bdde:31ee:f13c:79fb%4]) with mapi id 15.20.6954.027; Thu, 9 Nov 2023 08:30:45 +0000 Message-ID: <4e5da8a3-ce86-405c-b480-66cc1a6bbcd5@vivo.com> Date: Thu, 9 Nov 2023 16:30:42 +0800 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] mm:ALLOC_HIGHATOMIC flag allocation issuse To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Johannes Weiner , opensource.kernel@vivo.com References: <20231108065408.1861-1-justinjiang@vivo.com> <20231108135734.7b3820985c288ff98f41d2c4@linux-foundation.org> From: zhiguojiang In-Reply-To: <20231108135734.7b3820985c288ff98f41d2c4@linux-foundation.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-ClientProxiedBy: SI2PR02CA0048.apcprd02.prod.outlook.com (2603:1096:4:196::23) To JH0PR06MB6849.apcprd06.prod.outlook.com (2603:1096:990:47::12) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: JH0PR06MB6849:EE_|SEZPR06MB6871:EE_ X-MS-Office365-Filtering-Correlation-Id: d4a54845-f5f1-4fed-616e-08dbe0fe2afb X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:JH0PR06MB6849.apcprd06.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230031)(396003)(136003)(39860400002)(366004)(346002)(376002)(230922051799003)(1800799009)(186009)(64100799003)(451199024)(38350700005)(31686004)(31696002)(86362001)(83380400001)(26005)(36756003)(107886003)(2616005)(41300700001)(4326008)(6486002)(966005)(38100700002)(6666004)(6512007)(52116002)(478600001)(6506007)(66556008)(5660300002)(66946007)(66476007)(8676002)(8936002)(316002)(6916009)(2906002)(43062005)(45980500001)(43740500002);DIR:OUT;SFP:1102; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?MXpMdURrUjZoMXFlN25ZQjZMM1hSajRNQjIvbStwc21iY2VxaEh6QTRhVHpn?= =?utf-8?B?WUZRZnJZQmlzczhpUE5mQWRDTFA3aHNoaEZnSkhYaFhlbzlkOW9PQlJxZUtC?= =?utf-8?B?ZVQrL2tSOHNWTGFtdnFERWpQYjBMWkVsQlpRVHYzYXI0WlBhZVVJbGZqQ0Nv?= =?utf-8?B?bWJlaWlHUnFkM0Z3ZkxuRU1CWW11dmIvb3RXYktDMHE0c2dRQWhkTVQ2aG10?= =?utf-8?B?V0t1eStQVWFtQTNHdlJOSHI3OGVVNW00TUhSbUFYZWcrLy9EWml1RDhtOUlC?= =?utf-8?B?M25abnlVR01MZlpaS05KRWJTK0hNQkVwRndrV1lQOGdHNUtTU2dUMm5RWmtC?= =?utf-8?B?VCtVN1d1eG1GVWlSN1pwc2g3NWp6c2RWd2FPSVZXRzQ5M1RoYmJIRk5vTCtS?= =?utf-8?B?aExZUHcvc0RYWlZTNG1xUEUzeHN3VkFXazNXRjNOeHd1NXhra09uc28yd2VK?= =?utf-8?B?UXRwOHlYcWw4WGd2ampESHlhWXpaQWJWYnJua2Y5NmQ5bURhK1dxaTJDYmlw?= =?utf-8?B?ZTd1SlJLam1ualgvWS83dFk1eDJaV0k5Zit4MnlVaC9NUm1FWmlCNWhzZlhh?= =?utf-8?B?UEVKYktSL3dIakdPa0VEY1dwUHJPQ1VjOE53UTVlMUlMYVhhN1RzdXNMRVVN?= =?utf-8?B?QWFTdjUxeU9RaXJOQy9lcStQU1VRaDIrdWxBV1ZOQTRUS3pZZlJTdmtEc3Vk?= =?utf-8?B?aFJOY3ZlQStqOXdwNTJvTnovVDFKZnFiL1NQVHBKNmZzVjdxTm9jemZQV0gy?= =?utf-8?B?MVV0Ukt2bTUxUlFFTXRaOUxOandHS0dsMTVoek8rYkpkR1JLZkh4OFpyekdo?= =?utf-8?B?d2t2K1JJZE5sM2N1dHNmcldmblE5eEw0bXNwb2hFSjBZR3psT0NHYzNUSmdL?= =?utf-8?B?WlFROVo1THIwSU04ZXpoaDVZRmxQeFZRSjFlelhsSUFHRUJzZGliS1FIYzZG?= =?utf-8?B?OG1McUlFYmVNZ0lVYjhrc0ozN0RGTEk5ek10R01MMzJaSVhrTWU3Z0lPQVpK?= =?utf-8?B?ZnZINjVCRVUvUlVENTNVeU5NdUZGdTN1RCtWOUZmQzg5Z3ZwblMrREJmcXhG?= =?utf-8?B?ek5yUEVrN2NIM3dLUTdWRkM0Vk9wN2UwcWlSRkcrYjd4UnJyb090YjZWRnRi?= =?utf-8?B?VDJHREwvS0dRY1FzY0RMUnBYSkpLeTdEWHkwT09JVmNWQjdzRzM3VzlpQmpm?= =?utf-8?B?K3FPMkx0bDFTMkRvVXg5VW9HTEsyOTJoelpvVFVpN2tBdGVabzF4SFhLN2dN?= =?utf-8?B?RERhUnZxUDV6T1dZRmRYbjZnVWtFZ0l5NjlFb3I5b3NsanZyVlVVMC8rd0F6?= =?utf-8?B?aU56c1d4TzIyMGZZbW0yUklUWk11SDBkV21DVGkwRXBZblpCakJRNHZkaHV4?= =?utf-8?B?WnJ2ZHZ5MjZiSEJUdFVBWVJwdjF6RTRmUEJUVjBxVlY3YmVJZGQxUFYxc0tW?= =?utf-8?B?VGVFZERxb0hKZktoQkpxeERNZ2FNbmc0WE9ESWFBUkErWk5lQ2hVbWxNcW1Q?= =?utf-8?B?dG9tL0dLR2QrR2lEb0M2MzVzU0RZVkpLYUc3NEJNTW0ycWt2N1B5by8rbGd0?= =?utf-8?B?eldVcnl6ZEJXK29mVzZvTFZwdk4yZi9jMkw1c25kTzduaGNUanBaRGFaTk9J?= =?utf-8?B?c3ZXd0ZMaVlJWXpBaHhGSkJDTXBLNlhBaXhYbnFtckx4QzJPbEhRalIrL3lN?= =?utf-8?B?OGRwc2UyQ0lQc0pwL3Q2NFdQemY2cElCQXRzejJUTjNtR2tJb1NydDRhTnYw?= =?utf-8?B?aHBuMkQxam9yT0xSekUxTjFmV1JTMkM4eEgvZUE1eVlWejNPKzU4SGVDc284?= =?utf-8?B?RFl2NDVlSGZhRndCdWMvUHJjL2VBTDBzcWhLSnFhaHc4NWs3ay94VUpiYTdV?= =?utf-8?B?aHFCRlpmN3k5KzJVdmdjNzhCMTN1a1pjUm9WQ05IZmZkMGVycEpqNERtNFNh?= =?utf-8?B?Y1pTZmZXSHEvTWkxWEhWMHVFZit1Z0p1U1UzcUw4RXNSR0l0bFdoM09JUFRL?= =?utf-8?B?NE9KYVJZbTVMUE5WODkva2lrN0pwUDJxbENUeXZFaEloSkhHRG8wcWgwMkZx?= =?utf-8?B?UnFvdm5TNldRMGlVL3JaSWJsbUpiUFU5ZGRpeTUvNTR4dDVjN3poUUNtR1Nn?= =?utf-8?Q?QHvRCo4j7irJuvv7PyPy3I1h/?= X-OriginatorOrg: vivo.com X-MS-Exchange-CrossTenant-Network-Message-Id: d4a54845-f5f1-4fed-616e-08dbe0fe2afb X-MS-Exchange-CrossTenant-AuthSource: JH0PR06MB6849.apcprd06.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Nov 2023 08:30:45.1508 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 923e42dc-48d5-4cbe-b582-1a797a6412ed X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 5AHxcDZafTVXkuPHzDsXDggPpuu+751ooyiz2F2rGHnA/qp/vgIzcwlDTxEgSM7Q072/QoCsXbJThvGhABUbJw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SEZPR06MB6871 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 在 2023/11/9 5:57, Andrew Morton 写道: > On Wed, 8 Nov 2023 14:54:07 +0800 Zhiguo Jiang wrote: Hi Andrew Morton : In response to your three good suggestions, I have made relevant modifications in [PATCH v2 1/1], thanks for your review. https://lore.kernel.org/all/20231109073133.792-2-justinjiang@vivo.com/ >> In case that alloc_flags contains ALLOC_HIGHATOMIC and alloc order >> is order1/2/3/10 in rmqueue(), if pages are alloced successfully >> from pcplist, a free pageblock will be also moved from the alloced >> migratetype freelist to MIGRATE_HIGHATOMIC freelist, rather than >> alloc from MIGRATE_HIGHATOMIC freelist firstly, so this will result >> in an increasing number of pages on the MIGRATE_HIGHATOMIC freelist, >> pages in other migratetype freelist are reduced and more likely to >> allocation failure. >> >> Currently the sequence of ALLOC_HIGHATOMIC allocation is: >> pcplist --> rmqueue_bulk() --> rmqueue_buddy() MIGRATE_HIGHATOMIC >> --> rmqueue_buddy() allocation migratetype. >> >> Due to the fact that requesting pages from the pcplist is faster than >> buddy, the sequence of modifying the ALLOC_HIGHATOMIC allocation is: >> pcplist --> rmqueue_buddy() MIGRATE_HIGHATOMIC --> rmqueue_buddy() >> allocation migratetype. >> >> This patch can solve the failure problem of allocating other types of >> pages due to excessive MIGRATE_HIGHATOMIC freelist reservations. >> >> In comparative testing, cat /proc/pagetypeinfo and the HighAtomic >> freelist size is: >> Test without this patch: >> Node 0, zone Normal, type HighAtomic 2369 771 138 15 0 0 0 0 0 0 0 >> Test with this patch: >> Node 0, zone Normal, type HighAtomic 206 82 4 2 1 0 0 0 0 0 0 > Hopefully hannes can check this for us, but I have a stylistic concern... > >> +#define ALLOC_PCPLIST 0x1000 /* Allocations from pcplist */ >> >> /* Flags that allow allocations below the min watermark. */ >> #define ALLOC_RESERVES (ALLOC_NON_BLOCK|ALLOC_MIN_RESERVE|ALLOC_HIGHATOMIC|ALLOC_OOM) >> diff --git a/mm/page_alloc.c b/mm/page_alloc.c >> index b8544f08cc36..67cec88164b1 >> --- a/mm/page_alloc.c >> +++ b/mm/page_alloc.c >> @@ -2854,11 +2854,15 @@ struct page *__rmqueue_pcplist(struct zone *zone, unsigned int order, >> int batch = nr_pcp_alloc(pcp, zone, order); >> int alloced; >> >> + if (alloc_flags & ALLOC_HIGHATOMIC) >> + goto out; >> + > A comment here explaining why we're doing this would help readers. add in [PATCH v2 1/1]. > >> alloced = rmqueue_bulk(zone, order, >> batch, list, >> migratetype, alloc_flags); >> >> pcp->count += alloced << order; >> +out: >> if (unlikely(list_empty(list))) >> return NULL; >> } >> @@ -2921,7 +2925,7 @@ __no_sanitize_memory >> static inline >> struct page *rmqueue(struct zone *preferred_zone, >> struct zone *zone, unsigned int order, >> - gfp_t gfp_flags, unsigned int alloc_flags, >> + gfp_t gfp_flags, unsigned int *alloc_flags, >> int migratetype) >> { >> struct page *page; >> @@ -2934,17 +2938,19 @@ struct page *rmqueue(struct zone *preferred_zone, >> >> if (likely(pcp_allowed_order(order))) { >> page = rmqueue_pcplist(preferred_zone, zone, order, >> - migratetype, alloc_flags); >> - if (likely(page)) >> + migratetype, *alloc_flags); >> + if (likely(page)) { >> + *alloc_flags |= ALLOC_PCPLIST; >> goto out; >> + } >> } > So we're effectively returning a boolean to the caller via *alloc_flags. > > This isn't a great way of doing it. Wouldn't it be cleaner to pass a > new bool* argument to rmqueue() for this? Make it explicit? > > rmqueue() will be inlined into its sole caller, so this approach > shouldn't add overhead. Yes，I agree with your suggestion that pass a new bool* argument to rmqueue() for this, it is more clearer. I have modified in [PATCH v2 1/1]. > >> - page = rmqueue_buddy(preferred_zone, zone, order, alloc_flags, >> + page = rmqueue_buddy(preferred_zone, zone, order, *alloc_flags, >> migratetype); >> >> out: >> /* Separate test+clear to avoid unnecessary atomics */ >> - if ((alloc_flags & ALLOC_KSWAPD) && >> + if ((*alloc_flags & ALLOC_KSWAPD) && >> unlikely(test_bit(ZONE_BOOSTED_WATERMARK, &zone->flags))) { >> clear_bit(ZONE_BOOSTED_WATERMARK, &zone->flags); >> wakeup_kswapd(zone, 0, 0, zone_idx(zone)); >> @@ -3343,7 +3349,7 @@ get_page_from_freelist(gfp_t gfp_mask, unsigned int order, int alloc_flags, >> >> try_this_zone: >> page = rmqueue(ac->preferred_zoneref->zone, zone, order, >> - gfp_mask, alloc_flags, ac->migratetype); >> + gfp_mask, &alloc_flags, ac->migratetype); >> if (page) { >> prep_new_page(page, order, gfp_mask, alloc_flags); >> >> @@ -3351,7 +3357,8 @@ get_page_from_freelist(gfp_t gfp_mask, unsigned int order, int alloc_flags, >> * If this is a high-order atomic allocation then check >> * if the pageblock should be reserved for the future >> */ >> - if (unlikely(alloc_flags & ALLOC_HIGHATOMIC)) >> + if (unlikely(alloc_flags & ALLOC_HIGHATOMIC) && >> + unlikely(!(alloc_flags & ALLOC_PCPLIST))) > Again, a comment explaining the reason for the test would be good. add in [PATCH v2 1/1]. > >> reserve_highatomic_pageblock(page, zone); >> >> return page; >> -- >> 2.39.0 >>