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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5B07AC7619A for ; Mon, 27 Mar 2023 01:27:27 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id ABF066B0075; Sun, 26 Mar 2023 21:27:26 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A6F5C6B0078; Sun, 26 Mar 2023 21:27:26 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8C3586B007B; Sun, 26 Mar 2023 21:27:26 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 7C7FA6B0075 for ; Sun, 26 Mar 2023 21:27:26 -0400 (EDT) Received: from smtpin15.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 213DF40563 for ; Mon, 27 Mar 2023 01:27:26 +0000 (UTC) X-FDA: 80612940492.15.000FC97 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by imf18.hostedemail.com (Postfix) with ESMTP id 7CED71C0002 for ; Mon, 27 Mar 2023 01:27:21 +0000 (UTC) Authentication-Results: imf18.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=LGnXOUH5; spf=pass (imf18.hostedemail.com: domain of fengwei.yin@intel.com designates 134.134.136.100 as permitted sender) smtp.mailfrom=fengwei.yin@intel.com; arc=reject ("signature check failed: fail, {[1] = sig:microsoft.com:reject}"); dmarc=pass (policy=none) header.from=intel.com ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1679880441; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=sfR/SjSVIYGcPVziP4kpJKgB4yiUBuCCRpXs70UK0ys=; b=VL0xnb8RzpdPqLJLEGyA4QpUzMmTgJWjGdH39yDnGEMycnJcXJSIo7vcdb2gCyABz1LAXH IGiUIJfK/iFk62kYcD0RA+QmkCdN2XV1kV5UBiulrQ8TtIXOcE7X4wBULCvVx74WPXf9RQ 5datfGuTzehAK5VXXwvcHXhjD4fjbdM= ARC-Authentication-Results: i=2; imf18.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=LGnXOUH5; spf=pass (imf18.hostedemail.com: domain of fengwei.yin@intel.com designates 134.134.136.100 as permitted sender) smtp.mailfrom=fengwei.yin@intel.com; arc=reject ("signature check failed: fail, {[1] = sig:microsoft.com:reject}"); dmarc=pass (policy=none) header.from=intel.com ARC-Seal: i=2; s=arc-20220608; d=hostedemail.com; t=1679880441; a=rsa-sha256; cv=fail; b=PIxXgmPlmXEpEEi8MdebRr9xxvWdskCJ8lBHj++wmIXmtjDYOTbOFfQTvs9iO7wycexcXo hTAkXrwW8/IYiScqARsra3Tc0ooyza66dv/7Mh3K+JZdFN50yZRZBKOA1MS0wjTBQ23MYT k7aDfUv1FcFOih81gHhCgNmD1VgEMO8= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1679880440; x=1711416440; h=message-id:date:subject:to:cc:references:from: in-reply-to:content-transfer-encoding:mime-version; bh=lUpo7MlOcRVoo3I9us1eQD+7dyCzpUms2bKMyRfAF3M=; b=LGnXOUH51rLzvrQSg6NH/NVCJ/xLHtoHFtYK3U/EP/vHbeCmZ9Nbha2z KJsX3JI11X2s3TeEFxtWZWjN5NdnP7cplz+quB3dB1nBHWK50ZMkNKnLk 6enZD8Sn3jo6vj4oqQ3REaKSkosuUaXsHy5zzCcVKygPjOh1IAYqFNc2s TAQEBsRpNW59Uis+EauvPFj2RDkewxt+JFB1vWxRYuW22NXmsT0FNdVWO ulI2cKrkTo4TurXEyI8JPz51GcClc75GrCie9XtbE/X307k67AHNmqhWm kZxVyHCNaPWg3mlHbtDTeApsseRkoZduiNz/i3TZ2Vy2wXzozdv4+IKhb g==; X-IronPort-AV: E=McAfee;i="6600,9927,10661"; a="405077588" X-IronPort-AV: E=Sophos;i="5.98,293,1673942400"; d="scan'208";a="405077588" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Mar 2023 18:27:19 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10661"; a="1012914749" X-IronPort-AV: E=Sophos;i="5.98,293,1673942400"; d="scan'208";a="1012914749" Received: from fmsmsx603.amr.corp.intel.com ([10.18.126.83]) by fmsmga005.fm.intel.com with ESMTP; 26 Mar 2023 18:27:19 -0700 Received: from fmsmsx612.amr.corp.intel.com (10.18.126.92) by fmsmsx603.amr.corp.intel.com (10.18.126.83) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.21; Sun, 26 Mar 2023 18:27:19 -0700 Received: from fmsmsx611.amr.corp.intel.com (10.18.126.91) by fmsmsx612.amr.corp.intel.com (10.18.126.92) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.21; Sun, 26 Mar 2023 18:27:18 -0700 Received: from fmsedg602.ED.cps.intel.com (10.1.192.136) by fmsmsx611.amr.corp.intel.com (10.18.126.91) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.21 via Frontend Transport; Sun, 26 Mar 2023 18:27:18 -0700 Received: from NAM12-DM6-obe.outbound.protection.outlook.com (104.47.59.170) by edgegateway.intel.com (192.55.55.71) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.21; Sun, 26 Mar 2023 18:27:18 -0700 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=nRR8fQaznTjvJxr1o951IbSzFGHevQjSgMPY6Iha39MKO8vJ73QQlv4D98xSyqk2A0+vA81Nul6RLQDKbrgG+LLnR6CjXRUV4BZsefYIpAGvYXtK4NX3FSa1bqAnnOiJXCUuT67N4J2nPCgR8V8m/61VZkpFhLrXnHEDKEQlQgPASClJQBDrTXSXXQiAxZzwFA2GNRWoeqNpmbRV+OyEBxkQTuUoJSWkJrT0N2ukhp9par6TZZVvOh8kHufVLhNIluhAWoixohN/BTDHBBIQbsN+cZRoAGLJoDm2nNsEuUbihxvJudyjQNR+SEANCwOGdi/Pd6CGgtdYgfTbuUyNhQ== 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=sfR/SjSVIYGcPVziP4kpJKgB4yiUBuCCRpXs70UK0ys=; b=n4e3NO+uS7SFjOiPv5SDZtWJdef+t+aGY5wuTAmzGb2f3Sq1gzkOI29fiYO8qB8r6s5v0dSpdYnGiKASPzNKcHuxehhies6J3+0Sa1cD1/FVRIyvn58sc2mfIILrXMsOcdCg9jfcZzCe+0p1Ny2Fmdv7tLEPcxEZ6UMsljIl+vovwHSaQY9VrtT+ITFkc9Gr5sG2SRL8CNa5hWGoRdx3xJ22ATz8JtzpGem01LcnQuQSlVCm6TDMmlqfbqINu7D6vMvXNJedMsXaVjEuTF8WhNnJ6CnvHl6qfiGJ55zbYMvWHIKhx8V3gazwWMLadbUz+s4spYLtvJ5pzh6Kozg/fg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=intel.com; dmarc=pass action=none header.from=intel.com; dkim=pass header.d=intel.com; arc=none Received: from CO1PR11MB4820.namprd11.prod.outlook.com (2603:10b6:303:6f::8) by DS0PR11MB7216.namprd11.prod.outlook.com (2603:10b6:8:11c::12) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6178.41; Mon, 27 Mar 2023 01:27:16 +0000 Received: from CO1PR11MB4820.namprd11.prod.outlook.com ([fe80::8073:f55d:5f64:7c6]) by CO1PR11MB4820.namprd11.prod.outlook.com ([fe80::8073:f55d:5f64:7c6%8]) with mapi id 15.20.6222.030; Mon, 27 Mar 2023 01:27:16 +0000 Message-ID: <240650f1-a5cd-8b0c-fe91-0f8b116d6fe9@intel.com> Date: Mon, 27 Mar 2023 09:23:04 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.8.0 Subject: Re: [PATCH v4 35/36] mm: Convert do_set_pte() to set_pte_range() To: Will Deacon , Matthew Wilcox CC: Ryan Roberts , , , References: <2fa5a911-8432-2fce-c6e1-de4e592219d8@arm.com> <12d7564f-5b33-bdcc-1a06-504ad8487aca@intel.com> <25bf8e75-cc2e-7d08-dbba-41c53ab751b0@arm.com> <20230324145828.GB27199@willie-the-truck> <20230324172319.GA27842@willie-the-truck> Content-Language: en-US From: Yin Fengwei In-Reply-To: <20230324172319.GA27842@willie-the-truck> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SGAP274CA0018.SGPP274.PROD.OUTLOOK.COM (2603:1096:4:b6::30) To CO1PR11MB4820.namprd11.prod.outlook.com (2603:10b6:303:6f::8) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CO1PR11MB4820:EE_|DS0PR11MB7216:EE_ X-MS-Office365-Filtering-Correlation-Id: 4b19ce83-4f1a-479c-dcfe-08db2e62663a 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:CO1PR11MB4820.namprd11.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230028)(39860400002)(366004)(346002)(396003)(376002)(136003)(451199021)(2906002)(86362001)(31696002)(83380400001)(186003)(2616005)(38100700002)(36756003)(6486002)(82960400001)(5660300002)(8936002)(4326008)(8676002)(66476007)(41300700001)(66946007)(66556008)(26005)(6506007)(6512007)(966005)(6666004)(316002)(110136005)(53546011)(478600001)(31686004)(45980500001)(43740500002);DIR:OUT;SFP:1102; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?OFdkQnBqbG5Sc1NxalQ3Z1YzY0dVYWpieUMyczNOYW5BZFl5WDNkQ1h2WXN4?= =?utf-8?B?cHhpaXg2ZXpEM3F2YVljalB5TUNlL1VobWNtREdCUmVkdDNLbGw1UkpYYXBE?= =?utf-8?B?RHEyenlQWjBQd2lpazNDZ0E3cWcrQ3ZHay80TVkzeEhzU0hmbzFpZ0t1MFc4?= =?utf-8?B?M0lNT0F0blhPaVE2QkEzRndMbnVwS2lkMHRJZnZMVUJ6K0VoSCtTKzRwUjNq?= =?utf-8?B?OVFTWWdSZlAxUUxpQnI2b1lnUUFOYTFheHR0TzMwLy9GVHdFWCtwU0Z1NUx4?= =?utf-8?B?ckgrb0Jxc2hndjhoRnh0WTdabjZ6YmV5b3J1akVxaW9xTHNvVTRaWndsdDVV?= =?utf-8?B?U1FlVDM1M3lHNHR1b1RPSy9wbjJ4bzIwVnI5V2NNYWdjTVFnaVEzTjRDVm0w?= =?utf-8?B?ZGV2R1l3RDRiTVc0ei9IeUNTVnNzd1lhUzVvbktYSGVtUnE5M3RJaVNKTGdv?= =?utf-8?B?eWF0dERlNllWY0syS085citXSTNPVlN4OGNGbkN4VnkyVUNsVXBvWldNV3VO?= =?utf-8?B?c2RGOStWNEIxY0tVN1Jnbzh5SXBDY29NL1UxbWpCN0tGc0ticHZZeko4Lzk3?= =?utf-8?B?UTdIeXJLM2FES3MyTXdYL214ZGNLaGRsQ1pjdG5GLzM4TEhNT0p2ODVONk1r?= =?utf-8?B?MHVzbS80dHc3Wm11TzV2Vlcwb0FQNFhTM3hkMVh1YWlFNm96TGtXMUR3Z3dJ?= =?utf-8?B?V2ozbWRteithRDRudmptUkJoTTMwVStUL1NwSE1EYVJKeENWTm1CVmgwMEtR?= =?utf-8?B?bTlOWVg5N0VNV09DczlWK3NxOXN4cFY3VXd1QnRhVXN5TVVMWkdXMFA1Mkpq?= =?utf-8?B?RnAyVHpIQVNJMGpxRkx5U1g5OG5wL3RnbFFSdUVNdjFlU2I0TWRkT0Q4eSt3?= =?utf-8?B?SjEwTEtLK0RreVNCZ2psL2dGTlF5cmlNMTFPZlVnTG9vU29zWWpOd00zWXh2?= =?utf-8?B?eGlDVkpzUUhsR0dnOWpPTUpzTWVnVVBnWHhRS0E4L2k1QkFYdHdodzl4d1dK?= =?utf-8?B?Qm13aWdRa2xLQlBhcitnd2J4WEgrQlZHZHdIYlVvaktkUTBDYkFPdkNPTWVj?= =?utf-8?B?VHBybFl1cHJ5OFQxU2ZqdlJ0UkJFRFBnRlVFRDJWellKNWhidUkxYUtIdVpa?= =?utf-8?B?OUFhVHhVbHl3ekFMSHE5NHRLZ2lDVGtMTDQ0R0I3czZtNEsyaGpLUDNpQ2I2?= =?utf-8?B?MjZHd0svbDFKeFhLMS9FTmlJdVBzSkh4SXl2ZTlEUWZ6NmJXcThiV1YxZWtQ?= =?utf-8?B?NUd3c1hRL1lpakJiRW1aTFl0VWpncnBPNFNCYjhWeU04T2twenVOODFrZ1Rx?= =?utf-8?B?REQzTmh4SFZGemlwTU5icEJnWVAwR0RzK0VkNG92aVdiN1l5NFhTL2E5ODZP?= =?utf-8?B?WlNyTVY3eTVoWG92cXc1a05zOWZQZldFTVdNR0I2TTh2Y21kYnFZN3lXSjJD?= =?utf-8?B?WlpuRGl0Q21ubW1YYklYdDZTYUUyOHFyWUJuNnNBM1lQeG51RURCNkwvSE81?= =?utf-8?B?RmpwNk1QN0dwTVVUNEMvckxvTEY0dzRlcitsRElzS3JzbHplN295enA3bkhE?= =?utf-8?B?MkpyV05aV3Vib1lJSTB2MWdhRXFGNThTTldVWE55M0d1QVlLM3M2WE96N3ZL?= =?utf-8?B?dXZTZm92eGR0d21pRFR0SmdVQ2JCU0ZVTW5pMWlDU1hyZVZLT2R5d3dkSkpK?= =?utf-8?B?R0NteTZkSU1KNEpMMmFaUHJJS2MxNTV5VVZIUDlqZFhFekdTeDZJbVREaWsv?= =?utf-8?B?TTdDSmdmektRZ2RoUHRsTFFROTZEc3VzMmpOZ3ZMZWZFenlPeVBjY0prRXdi?= =?utf-8?B?SHlMcG9ENDRtZkgzOWt0d3NXa1hiNWViRFNucXJRNXN2NVlXSnpoSXZVRTV2?= =?utf-8?B?VlNSSFI3K1FVb01vYlc2bGxvbnhtakFDTDk2c0RwNFFkN3Q5TERMMGpUajkx?= =?utf-8?B?c2MxSWlQZS82RnQ4eDlBSm96YlFuclY0WU12NVFDdjh3TmRYUW40ZWQrY00r?= =?utf-8?B?aGVSbkVvSFUwK0hxSlNMQ21aazdYWXlJcFJNelRESjczbHRpaDhuN0ZuVlBH?= =?utf-8?B?V3VJUTB3ZjBTSDhuVml2ODlxYVFHL0k2Sll4RW4wWGlHV09haHUrME5SVEtm?= =?utf-8?Q?cJ0CmkjzYuAjgiFI146xtv6JM?= X-MS-Exchange-CrossTenant-Network-Message-Id: 4b19ce83-4f1a-479c-dcfe-08db2e62663a X-MS-Exchange-CrossTenant-AuthSource: CO1PR11MB4820.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 27 Mar 2023 01:27:16.3542 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: VaRjZHL1/pIdftiWgb2daG/FykEMx3ziZnbGje7WUXZTcAFscEIneE89P8CVaidnVxe731NN0GehC0tFdmAvXQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS0PR11MB7216 X-OriginatorOrg: intel.com X-Rspamd-Queue-Id: 7CED71C0002 X-Stat-Signature: przpwfz49g8er9mxmcqa5x4m9yxh7z8q X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1679880441-325510 X-HE-Meta: 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 uO3GysLG B4x41ZZasAEl6r8aEih01zQVa6IcSCoYi0hyl/ZhPrQcrUI8vSZ/a4m4dNcnJlbbSO6kxvi+pZY3I37qv6Ndg1oih04Be4nk2A7qqnisLPSbvmO6Q6cO6d5DhldPX87ygv/PNrCpYVzZAlozgvb6ersOhWkcl0vK0ZMlmulNRqUkjNLRAv/2Sb+cGXbOXPVoVkDmZkwLxYMkipjC9jgJNycmoEHfgUz5hy3MuePhKMgcGCAO4cXyLli1g9Uv448f7QX5/c8np4WjUPEXDLa40xANvREeMaf/2NTxpZ68uMcSFdzNPS2J/eTYSDIPPo7IaIPQkJUnCPHqo1+fBEbq6clj7x2eyJ0872mmU8Th5D0gY/PXK0rf7UxYLFJnxh2nuKCXsgqYnauNoMEljIk4f/RQCtQ== 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: On 3/25/23 01:23, Will Deacon wrote: > On Fri, Mar 24, 2023 at 03:11:00PM +0000, Matthew Wilcox wrote: >> On Fri, Mar 24, 2023 at 02:58:29PM +0000, Will Deacon wrote: >>> Yes, please don't fault everything in as young as it has caused horrible >>> vmscan behaviour leading to app-startup slowdown in the past: >>> >>> https://lore.kernel.org/all/20210111140149.GB7642@willie-the-truck/ >>> >>> If we have to use the same value for all the ptes, then just base them >>> all on arch_wants_old_prefaulted_pte() as iirc hardware AF was pretty >>> cheap in practice for us. >> >> I think that's wrong, because this is a different scenario. >> >> Before: >> >> We faulted in N single-page folios. Each page/folio is tracked >> independently. That's N entries on whatever LRU list it ends up on. >> The prefaulted ones _should_ be marked old -- they haven't been >> accessed; we've just decided to put them in the page tables to >> speed up faultaround. The unaccessed pages need to fall off the LRU >> list as quickly as possible; keeping them around only hurts if the >> workload has no locality of reference. >> >> After: >> >> We fault in N folios, some possibly consisting of multiple pages. >> Each folio is tracked separately, but individual pages in the folio >> are not tracked; they belong to their folio. In this scenario, if >> the other PTEs for pages in the same folio are marked as young or old >> doesn't matter; the entire folio will be tracked as young, because we >> referenced one of the pages in this folio. Marking the other PTEs as >> young actually helps because we don't take pagefaults on them (whether >> we have a HW or SW accessed bit). >> >> (can i just say that i dislike how we mix up our old/young accessed/not >> terminology here?) >> >> We should still mark the PTEs referencing unaccessed folios as old. >> No argument there, and this patch does that. But it's fine for all the >> PTEs referencing the accessed folio to have the young bit, at least as >> far as I can tell. > > Ok, thanks for the explanation. So as long as > arch_wants_old_prefaulted_pte() is taken into account for the unaccessed > folios, then I think we should be good? Unconditionally marking those > PTEs as old probably hurts x86. Yes. We do only mark PTEs old for arch_wants_old_prefaulted_pte() system. Thanks. Regards Yin, Fengwei > > Will