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 0905FC41513 for ; Tue, 8 Aug 2023 00:02:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230452AbjHHACu (ORCPT ); Mon, 7 Aug 2023 20:02:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41338 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229628AbjHHACr (ORCPT ); Mon, 7 Aug 2023 20:02:47 -0400 Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.136]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 099D5BD; Mon, 7 Aug 2023 17:02:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1691452965; x=1722988965; h=message-id:date:subject:to:cc:references:from: in-reply-to:content-transfer-encoding:mime-version; bh=iLsAI05iVgfkB1N2st8m/Rx7c7rCmLQqmQ5UKrcjgBs=; b=d9S77yfAEs/pNSaq5jvktx5j0xDdp/9PgNKiDY/Vq8TsipZjNBOBAEtS m/oolV4EB21QpwruYXttuxCMlv5KEBSZ57fAbj1dUfsTjaLDydf6zRSt0 abhCqjJL/8CsUIF2YB9tALl98JwyT49oHeU1ilSM9YyumsZg5UN+0H7zr 1CNcIAAFuMy92BhEMks+iiEz6xm0mfoDR2sPCCMcYoDJnwx7MJOA0ODzN /IyvQaU1luinXbS4bnBTdXWgb/A9Mi6y07eWPzk5UFSEEHsRF2aLoNnk3 +1TbfdmTNjVSVMcuqwM3uKO4RHmm5QuY5GiKcVOgkmF45x4BSE3Y0LFWM Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10795"; a="350272033" X-IronPort-AV: E=Sophos;i="6.01,263,1684825200"; d="scan'208";a="350272033" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Aug 2023 17:02:45 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10795"; a="821145705" X-IronPort-AV: E=Sophos;i="6.01,263,1684825200"; d="scan'208";a="821145705" Received: from orsmsx603.amr.corp.intel.com ([10.22.229.16]) by FMSMGA003.fm.intel.com with ESMTP; 07 Aug 2023 17:02:45 -0700 Received: from orsmsx611.amr.corp.intel.com (10.22.229.24) by ORSMSX603.amr.corp.intel.com (10.22.229.16) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.27; Mon, 7 Aug 2023 17:02:44 -0700 Received: from orsmsx610.amr.corp.intel.com (10.22.229.23) by ORSMSX611.amr.corp.intel.com (10.22.229.24) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.27; Mon, 7 Aug 2023 17:02:44 -0700 Received: from ORSEDG601.ED.cps.intel.com (10.7.248.6) by orsmsx610.amr.corp.intel.com (10.22.229.23) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.27 via Frontend Transport; Mon, 7 Aug 2023 17:02:44 -0700 Received: from NAM10-MW2-obe.outbound.protection.outlook.com (104.47.55.103) by edgegateway.intel.com (134.134.137.102) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.27; Mon, 7 Aug 2023 17:02:44 -0700 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=mxcJVgnp5ImicGVILhdCbOOAR6uTC1mjgWqWr1IkR7IzMgTRv0p51J9H4l+SVZ0dyK7USua+zdwG/7jCirs+ymZDLkA/0lP11kTMX/tByqU/EbopQrnlEsn88wJ9Mx/CLnspBQeOOYFQhWHe3XOcmfIFEQviqQbehYmhT6bXKwPlnAEXBMj2Wk0a2yX89KRx7/pQG+JMSBWf6y55bEmbHf/nGWPw1MonGSpTyxB0EbHpmh+ciS4RDZKC8DVR6PAZPU2Oy0lmjWxTr2XE+OCaQY3K3m+lTMDB5qiT0KORF8+6JrqxuiKCH4L5vYvqI05ZJyFqfRib1w8gNWXAE+wPAw== 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=iSkH9HsPoS+Dkj4bOXnNHIopqeHtQMORfjo5cVYVbKQ=; b=TZ/qVMyQwB8VLR+mVqssmywXoAAmOhjza2FyM5YQE4hbCu2FPoNAO4rjnAqyepz8JXOeAB/4Xp65NGU6JYJuOWRfNvcMYpPo5vwaLTq3L2FlcTwMrGO9tZuk0yxH9PeJfDznz5RO3ZO3TBIr+ZvH7M/4d/XaCrElUqsyNdAl9K8ifFKjyWDXXcbbkBiDp7M50zqafkYwz47A1urtzXq5TAQJvhIejQa2ecSQqxIksEhfOACWntWRifXEX/MTrvbKQ0XhrBwHCGkyaBcE46uRRqg8Kz5kqViotL1RYF4Gds/ow2+FtQsqcH71zf4sbc8jJfGbiuUyec94VTnJTIQ/ew== 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 Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=intel.com; Received: from CO1PR11MB4820.namprd11.prod.outlook.com (2603:10b6:303:6f::8) by SA2PR11MB4986.namprd11.prod.outlook.com (2603:10b6:806:114::13) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6652.26; Tue, 8 Aug 2023 00:02:37 +0000 Received: from CO1PR11MB4820.namprd11.prod.outlook.com ([fe80::221b:d422:710b:c9e6]) by CO1PR11MB4820.namprd11.prod.outlook.com ([fe80::221b:d422:710b:c9e6%3]) with mapi id 15.20.6652.026; Tue, 8 Aug 2023 00:02:37 +0000 Message-ID: <9e92e42d-488f-47db-ac9d-75b24cd0d037@intel.com> Date: Tue, 8 Aug 2023 08:02:28 +0800 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 0/2] don't use mapcount() to check large folio sharing To: Andrew Morton CC: , , , , , , , , , , References: <20230728161356.1784568-1-fengwei.yin@intel.com> <20230728102405.7b456eb87fb46042fbce5e4b@linux-foundation.org> <29cd58c4-08d3-c03c-7232-15f85878934d@intel.com> <6dbf9f37-e4bf-656d-4121-789e2e6cfae2@intel.com> <20230807094342.17199a897f51a298f20fda57@linux-foundation.org> Content-Language: en-US From: "Yin, Fengwei" In-Reply-To: <20230807094342.17199a897f51a298f20fda57@linux-foundation.org> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: OS0PR01CA0041.jpnprd01.prod.outlook.com (2603:1096:604:98::12) To CO1PR11MB4820.namprd11.prod.outlook.com (2603:10b6:303:6f::8) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CO1PR11MB4820:EE_|SA2PR11MB4986:EE_ X-MS-Office365-Filtering-Correlation-Id: 6dd544b7-e871-4344-609d-08db97a2c610 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)(346002)(376002)(366004)(136003)(396003)(39860400002)(90011799007)(186006)(1800799003)(90021799007)(451199021)(41300700001)(26005)(2906002)(5660300002)(31686004)(7416002)(8676002)(66899021)(8936002)(2616005)(6916009)(86362001)(316002)(31696002)(53546011)(6506007)(6486002)(38100700002)(82960400001)(478600001)(66476007)(66556008)(6666004)(66946007)(6512007)(4326008)(36756003)(43740500002)(45980500001);DIR:OUT;SFP:1102; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?K0RVWGdQTXEwc1NqcUp5VE02ckc1MU9NVXRuWVVwRE9xUWw2dWZteWpHZURz?= =?utf-8?B?cHRSaDJrNERtN3dVYzgyNmxTOC9CTk1jZjBzK01zWmtjTWVRTll3MHE3WFVx?= =?utf-8?B?WFhDbjJnTW5iRncyOEt4M3JQWHV5RXFXMkVmcTBRS0xGWFQyd2xOUE01N1N2?= =?utf-8?B?R3JncWVESGtJNTNuWFhOeWNNZnZ1ZVh6Q2RWN0Y3ZkJHM29nRkYydUFWa1Rr?= =?utf-8?B?L0tVRm5aL0pDcmhiZ0E4TDNpTFQ5SkMvTWoxaEJBUDByRUVuczFYTi9TV0xh?= =?utf-8?B?bTF6b0JkRzVxcHZLK253N2tORG56ZVZKM3VkQVY3dlNaUDJqS29zNyttLzlF?= =?utf-8?B?UVVDeVFoa1Rud1dZdWZpNUYwZWZGaFZlT1VNRjdGZGExYnR4WE9FaHFFVkox?= =?utf-8?B?U0djWHNjT3lyYmMwUmZDbVlSSXhxMGJZcWdGQXMrcEFsV0FkTGRlKytnaVNt?= =?utf-8?B?ampUYjF0eU1YY3lOSEVmTUpnbStFcWdFMDR1bHByd1ZMNGIzRHNkN1hpaXhZ?= =?utf-8?B?UEJZaW1nTFFqQmVEMTNLaVRheGhPYXFnclFvTEdQQkxkVC9XRFpyWHc5YU5Q?= =?utf-8?B?S1h3bmJNU1lVQU5QNWxFMzlFQ2EyYy9xc2pHZG1JLzhUSWZiRXhoRWFzbHRa?= =?utf-8?B?OGpOWW1YQUZ4MnVWSnUxYmlzQlpVVWdtWjVYVWRSWWRpMmtzdG1yaU91WHZH?= =?utf-8?B?L1VJZ3dMdlVPOEp3MklsTDVmbFFESVMzRld1YWlkcHFZZ1k0aHZaTlBZb1Y4?= =?utf-8?B?Z2tkTlpDVlhqYThUUkxmWG9sOVVIRXQ1VVppVUZRSkpCRHFmV2FjR01WQ3dp?= =?utf-8?B?WktEaGpXMnNNL1hUeWpzWEdpQmlLdm81UjdEejhrMmt3bWllOWFsR2dUOTd1?= =?utf-8?B?RUJIWENCVVVuQVgzK1VjMy9rY05Vb3dxckNZM25oYkJmK1NudEcySXF0UEJ1?= =?utf-8?B?KzdkZzlKNVByN1lBNnBZQUpQQll0N3U2V3Y1U0VLWmdFOTJkNVJ1QXlHekdY?= =?utf-8?B?TUJDL1VYMkIycWdMaE5qUFJnWUh1MlVndllDaEFhT0JraEF0YldmUHpmY0E4?= =?utf-8?B?OHIySWhqdnRzNXVIRDBSZXJZZXN2L3ZVWnU3UU9PdE9NemVvKzc2NWwxZGVj?= =?utf-8?B?WGZkUU1BeDBORHl5RmoyRXVVVW5xaWJtM3NGaWhyQjVwNUQ2TmhhWXovajJl?= =?utf-8?B?b0RxOHVnZmE4cUNLWG41K0tiOFhUSnBVaWhlQU4wT1pYZzlQZWNIc1pQS2xk?= =?utf-8?B?L2RJNmlkU3E1UXZoVmJsYlJ6enRkSUxiNHUzbXlwdFBvQUMreXI4a1F1Zndx?= =?utf-8?B?T1h2ZlZvcGpxZlFvRFNUZnpkWURyNkU5SkFmeitLQXlsU1RUVVdGMzZNMHll?= =?utf-8?B?QjNuYWoxODNvUWVqell0UXhHZ01CNDd4dHhmZ2dzTUhnY3JhSmtobVNuVkdW?= =?utf-8?B?Y0Vud0I5aHY3cGpYcDZxMk5acjdEeWdnY25rT3Z5QlhDd1RYUzBRcFhlVlph?= =?utf-8?B?M05SczVwQkxVR1JJaFpseEFlN3ZjYmE0RW9WZm10RXVoU3hXU0wrR2NpOUFq?= =?utf-8?B?cVNHOVlzSk5UTkxpclU1RWVHNWEwM0M5WHFhVURYckw2N0pUUmR1bGpha0Nn?= =?utf-8?B?UTI2dkx1MTRMckdDZXBIRTByQ2FuNzVYTW1IMjVMQzRyQ2p3ZjBOZEdCS21M?= =?utf-8?B?WWd0WCtXZFo5aXg3OWRyQWxPc1FQbzIveHhpTEpUZEIxUGs3NUZqMStNZmVU?= =?utf-8?B?c1YzelpWS3BCemtQZlZzT1AvU0tnUmthUWQ5dEE0c043MzFabWVta1dsUE1s?= =?utf-8?B?Q0U5MC9TdnpuTDFSMXo5MkpWTDRqY1N4RXZnYVdxS2hoWnpaeFRjOXZoS1M4?= =?utf-8?B?dTFQUUI0T0tyQUJIMXRGWmhhekVGVzJaWXBpTVZFeE15Mk83TS9NS0FYcWJm?= =?utf-8?B?bW1WS3RZSXZVVUdhWDhyOHM3bVMrNTdhOWF5dWpwdVNmSlF4cHlPbjhEZ3Mz?= =?utf-8?B?RkRCd1d1Q1FWZUhMaXM4QkRMVHBrblJFck1GQjlxdHVvQXg4UVJHVmlpZXFG?= =?utf-8?B?QmF5UGxkVlRCN1JmNWVpQXIwU3Jod0tFQ3BydWFiUVNiSVRTTTM0QjBRaWFv?= =?utf-8?Q?NGEtBFIpsh+KqpFY4UYU1zVgM?= X-MS-Exchange-CrossTenant-Network-Message-Id: 6dd544b7-e871-4344-609d-08db97a2c610 X-MS-Exchange-CrossTenant-AuthSource: CO1PR11MB4820.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 08 Aug 2023 00:02:36.9663 (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: na3NpvwRAHPOKqoEAo9dqA5u40lEGYwyLmna5cAJy8ZYI8b8viIu4TMIPKHNzmnziRdvHmSPpzN0+QvTtonOeg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA2PR11MB4986 X-OriginatorOrg: intel.com Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Andrew, On 8/8/2023 12:43 AM, Andrew Morton wrote: > On Fri, 4 Aug 2023 15:14:53 +0800 "Yin, Fengwei" wrote: > >> Hi Andrew, >> >> On 8/2/2023 8:39 PM, Yin, Fengwei wrote: >>> Hi Andrew, >>> >>> On 7/29/2023 1:24 AM, Andrew Morton wrote: >>>> On Sat, 29 Jul 2023 00:13:54 +0800 Yin Fengwei wrote: >>>> >>>>> In madvise_cold_or_pageout_pte_range() and madvise_free_pte_range(), >>>>> folio_mapcount() is used to check whether the folio is shared. But it's >>>>> not correct as folio_mapcount() returns total mapcount of large folio. >>>>> >>>>> Use folio_estimated_sharers() here as the estimated number is enough. >>>> >>>> What are the user-visible runtime effects of these changes? >>>> >>>> (and please try to avoid using the same Subject: for different patches) >>>> >>> >>> Can you hold on these patches to mm-unstable? I think we need to wait for >>> David's work on folio_maybe_mapped_shared() and redo the fix base on that. >>> Thanks and sorry for the noise. >> Sorry for bothering you again for this patchset. >> >> Let me explain the situation here: >> - The reason to hold on the patches to mm-unstable is that I don't want to >> promote the fix in this patch (using folio_estimated_sharers()). The >> correct way is waiting for folio_maybe_mapped_shared() from David. >> >> Merging these patches motivate using folio_estimated_sharers() in other >> places. So once folio_maybe_mapped_shared() is ready, we need to replace >> folio_estimated_sharers() with folio_maybe_mapped_shared(). >> >> - For this specific patches, if they are suitable for stable, we may want to >> merge it (special for stable branch. I assume folio_maybe_mapped_shared() >> may not be back ported to stable branch). >> >> So how do we deal with this situation? Thanks in advance. >> > > I think I'll stage them for 6.5, with a cc:stable. > > I'll drop the current three patches. Please resend with Thanks. Will resend the patches. Regards Yin, Fengwei > > a) different Subject:s for all patches and > > b) changelogs which fully describe the user-visible effects of the change. > > Thanks.