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 5BB64C4332F for ; Thu, 29 Dec 2022 01:15:28 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A97638E0003; Wed, 28 Dec 2022 20:15:27 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id A208B8E0001; Wed, 28 Dec 2022 20:15:27 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 825D98E0003; Wed, 28 Dec 2022 20:15:27 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 715F68E0001 for ; Wed, 28 Dec 2022 20:15:27 -0500 (EST) Received: from smtpin13.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id 33225A08ED for ; Thu, 29 Dec 2022 01:15:27 +0000 (UTC) X-FDA: 80293575894.13.B44BC86 Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by imf10.hostedemail.com (Postfix) with ESMTP id BC96BC000F for ; Thu, 29 Dec 2022 01:15:23 +0000 (UTC) Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=ZwERctMk; spf=pass (imf10.hostedemail.com: domain of fengwei.yin@intel.com designates 192.55.52.151 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=1672276524; 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=vsdxik5Bl7fdxWNCS/7eZttT0Uq8wT7kU8Ab364Mc4w=; b=hJPxJXN7VkleKiqXhAJJE42Wx/zOsvv4IZJra7L7+EPUJ+kPe15tBzbpfuHmPr7ool6+26 jwmCasXlW9wcr7OKQ3MG8PUd5SA8DyOO3u2XFFZ6BdHM20uJyBuuhj/r4EdFaH/v2vMQgG TlUaAU/xbomVimkDtBKACrTY90cSv2k= ARC-Authentication-Results: i=2; imf10.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=ZwERctMk; spf=pass (imf10.hostedemail.com: domain of fengwei.yin@intel.com designates 192.55.52.151 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=1672276524; a=rsa-sha256; cv=fail; b=v/LrICYDfKFfhZJTRY2M6SV7c1l0n15tKezhZ4el7o+bbSGPXiOm375UEMbVs2W2UEhOhB 6nWdnp1zrgiBeZcaUY4m/Eljb6s2on0KXnKIavMtPU/QnihjSe6oAzHzNPvPqEOokXYOk2 cz3zvmrlghTMtRBHHffQiYbZy614ZEA= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1672276523; x=1703812523; h=message-id:date:subject:to:cc:references:from: in-reply-to:content-transfer-encoding:mime-version; bh=qnJ6kbgEteaS3At8oFKBUjdNc8GT2Zrvnuu9EsWYWvs=; b=ZwERctMk8BBZIW3mJ5KgcMGccjfCHsBs8TtEnO/g1gf2wUDPse88aNlO dxDc9j0n42KP7yd5v04kGfiUKok+wGKEJ5r/1j1ZG0EznaQYcFrwp+rPs 3W/th0/PPsQhjTqwCN/Y0ChP+0vr5Ayer2KtMZoy2dMbvPtrzB0jpJkKT g9gOMTa0oyZ0s/4Les+4hckeqq7SsPZYObDufHRZ7OeiIjc/uq6CDaBbQ PG6cbDixhrmWX3/2NN8Ok7cBYBsBHZHa6qTvorKby7BbA2lFsywiqoWN0 u81BjTzlMfk2IDzX/QyFI2Wy/xJi3WZOdowILwS+Up83t5TuEnfCfPQoT g==; X-IronPort-AV: E=McAfee;i="6500,9779,10574"; a="301325857" X-IronPort-AV: E=Sophos;i="5.96,282,1665471600"; d="scan'208";a="301325857" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Dec 2022 17:15:22 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10574"; a="685832621" X-IronPort-AV: E=Sophos;i="5.96,282,1665471600"; d="scan'208";a="685832621" Received: from orsmsx601.amr.corp.intel.com ([10.22.229.14]) by orsmga001.jf.intel.com with ESMTP; 28 Dec 2022 17:15:21 -0800 Received: from orsmsx611.amr.corp.intel.com (10.22.229.24) by ORSMSX601.amr.corp.intel.com (10.22.229.14) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.16; Wed, 28 Dec 2022 17:15:21 -0800 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 15.1.2507.16; Wed, 28 Dec 2022 17:15:21 -0800 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 15.1.2507.16 via Frontend Transport; Wed, 28 Dec 2022 17:15:21 -0800 Received: from NAM02-DM3-obe.outbound.protection.outlook.com (104.47.56.42) 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 15.1.2507.16; Wed, 28 Dec 2022 17:15:20 -0800 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=RHJ4oQdHa6Uy4SYtwpJ8c+fDwZkRT9YlWQJPd/BgXcAw7fdK/tn/EK7qu+QP37LS2KyLfNvMAcKiowfP/qOx1Hk0Qz3RI9Hx+OjjAgIdG0+b6sW1DcImThZF+H5C2LfRk+S/Vrgu6d44hFqLdb0XRnbD1akRktpE4/8zQWCavleyCsulNhKmkoQovKvluoAAdr313ep+pbxpiNkDais+kgjrbHV2QpIoSndmWh0LhkHICo61HU3dUDkP6bKi4kLNDoIRqEF426qEDKTHASf+lUp5mwG8NOHMQOz455F9NYyX2IbQRL3/Cr+hrXJeeaPty/LImEpI9RV/LEEHjuKemg== 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=vsdxik5Bl7fdxWNCS/7eZttT0Uq8wT7kU8Ab364Mc4w=; b=Gs3+0sTh1yGaVWIPsigXwucsVfzd7Vo+d4JVxrtABaN8ppJhbidLhk8e+8apeFbB1f6Km1gJmKQwFhD2WEh52Ss72q7iRQblH/iubViu6smlo7zulIYsTRUX3zwSQrtLUCl1XMQZwwTQx+ebeWG9FTkIj9GVGgLy+8IOkqbGUN+cPQ+HczVm8HMgP+S2i2QMSbs8BM8TX6h0mC2h/Ql0ozmG0hMS14M/UNcqFaVMVfnhavVUX/xs+Lq+mB3uP3iq2FRe+Vy2kkXlq5bioo9cnUjRFnBeuD8eEKOZWWR+TfKIFuVRrnYpyA5Y00bIslm7G0tARyjR/cV3iafQhmkgMg== 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 PH0PR11MB5174.namprd11.prod.outlook.com (2603:10b6:510:3b::12) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.5944.16; Thu, 29 Dec 2022 01:15:18 +0000 Received: from CO1PR11MB4820.namprd11.prod.outlook.com ([fe80::505b:18be:f1dd:104e]) by CO1PR11MB4820.namprd11.prod.outlook.com ([fe80::505b:18be:f1dd:104e%9]) with mapi id 15.20.5944.016; Thu, 29 Dec 2022 01:15:18 +0000 Message-ID: <939213e4-b54e-12c1-1b3e-b179b39dc0ed@intel.com> Date: Thu, 29 Dec 2022 09:15:10 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Firefox/102.0 Thunderbird/102.6.1 Subject: Re: [RFC PATCH] mm/thp: check and bail out if page in deferred queue already Content-Language: en-US To: David Rientjes CC: , , Andrew Morton , , Matthew Wilcox , , , , , References: <20221223135207.2275317-1-fengwei.yin@intel.com> <677d82d8-f8c9-9a60-3af0-e7931c7728c6@google.com> From: "Yin, Fengwei" In-Reply-To: <677d82d8-f8c9-9a60-3af0-e7931c7728c6@google.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SI2PR01CA0049.apcprd01.prod.exchangelabs.com (2603:1096:4:193::13) To CO1PR11MB4820.namprd11.prod.outlook.com (2603:10b6:303:6f::8) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CO1PR11MB4820:EE_|PH0PR11MB5174:EE_ X-MS-Office365-Filtering-Correlation-Id: 6506fc20-311c-4536-3103-08dae93a25bd X-LD-Processed: 46c98d88-e344-4ed4-8496-4ed7712e255d,ExtAddr X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: BTtjKscPMxVAKWRS1IUrcofbjgjWTPqSUOhma2mPrMFAwW5znqy7s9oU22y1wOlzXYqHsYw3GjzBLEPMM1C7RbwLAhn2BZijD8rVk8pmlSDvhKa8jmleXaBsDhRfBGvmxz+/BP9ZflO6S/WNQ7dbx1rLDgTPos0yJWwFxEDf04x/SVuKHyFcbij7qEe3ZSuZe9K9qNXu1b68alDyw92TYXDR5LBMqQpPuiDLmQtC/R1BNgl5W67mvc22QurSWztkKK3aBNlm2ZvngMqn/eoySlTt/5OWTpOVA3sJAV9kn8uiWWEQ3ksxWdvaik/KxnmgLCuX9bSCP75C1Vx9CA9O5nka5hZkz4IebaqmxDHEgRGljIOMrbOArUZ9msAbFW+ugOkdqMr8lA4aC4EJm142pLgMKnijXf/voQG2oxF+7chvaJCIu7jRdTq5bXxt4b44BZyY4RpmkhTLbuDedm3Je0OCgJqReYf+EXrkIkREGUcsTMdkCID/2A+R540pjoH32i17VaGgVkVv4c4Ec+1f+qY7x+6y4B3wevmU18xruvzJrsRJYwib16ON49NixbhPYL/7lXaemhHksVFl1ScHHHYLf0SlpgSbD9OMEhii1xnU60mDN9IQB3w9yDUIJyBmvlbryMUDQqJSR2aUVf9uf4cRjO576Uy0S5nL4Ehl7WjWkOTqCQ3kpfKJ0NLCayS25VItkToGtBZBioif9DNuIqbXfJhR5Ii20sU0OvPfwYnDsDkQ7Y4f5txfE90phbIA 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:(13230022)(396003)(376002)(39860400002)(366004)(346002)(136003)(451199015)(83380400001)(5660300002)(66946007)(66556008)(66476007)(41300700001)(8676002)(31686004)(8936002)(4326008)(86362001)(82960400001)(6486002)(966005)(31696002)(2616005)(6512007)(36756003)(38100700002)(26005)(186003)(2906002)(316002)(6666004)(6916009)(478600001)(54906003)(53546011)(6506007)(43740500002)(45980500001);DIR:OUT;SFP:1102; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?ME9aMFV4a3hpU3QrcnJCNFZ6ZFJPNnJFL3g4U1NINExLUnFxOE9TajBZVW1F?= =?utf-8?B?SzUrK0VaN0pkQnk3K21WaTVEOC9vYjF1WlZpbzF3VkM2dlF2bSszV3g0WUM2?= =?utf-8?B?VGprekt6dDF0eVVJLy9nVVJ3V0p2dWE0VHNLOEEycWp0QnAxTlhhMWF4WHBl?= =?utf-8?B?aWNhQ2dEbEdBaTErenl2Rzh2Y0JKN00vT2hMOHdqZmIwTzFXclBRSVdQcWE5?= =?utf-8?B?VU1UMUZ3RWxLbGtONEM3L292Qld0MFJXQWJreXMyVVIxTUluTVZWMm5QbS8v?= =?utf-8?B?QkR4QUVZVlBhNFZsZ2xMRGs2ZXZIdHVVdTZsUzNYWjhnNHUwMzJ0SWtBbG54?= =?utf-8?B?NTJ5QlNCc2tuV0hRcjVGQzVSV1BmTkFEQSt1TmRUM0tzUFRIWDBnckkrLzhF?= =?utf-8?B?QUJySndYZ1BpeVRURmRiaW56MUdJM1V6UUZlUU9QZDZPMVFZRGZ3TjBQbURD?= =?utf-8?B?eHJtdmZQTjFYZ1hhK2pSSVQva2daa3J2VHhnSVpvY1B3Q24ycFFlTHovSTFL?= =?utf-8?B?VXhyMUlLY1BYTXgwb3hnR3BPTFZXRUdVOG1nTDVYaC9rTVpzYUkzdTlnQ3Jv?= =?utf-8?B?R1NUenhJZXovZTMxZmVrVnNGbWR0MlZ0LzN3RmhYSVZta3UyRVByTTVieXl6?= =?utf-8?B?QXNEcXV4dW1oVjR1S1lhUTA4SzFWbGQycytkUVY3UlhQdG0zU05kZU9Wa1Z5?= =?utf-8?B?Q3BYUkJOMFRUYkV4YVNJNnlvSGkzWk1LQm1teXJHa0pJcEhBVWdDeThIMGhi?= =?utf-8?B?dU5HczhKck1kN203S2xRb0hmRjRZbVhpRzlLWUZEL2ZxbXVxWkF1NjlvYkpU?= =?utf-8?B?eEhrQUZZSHp6V0xCOGtpT0hBekM5cUVITGlycU5mdjAweHhDY2hhL0I0Wk8r?= =?utf-8?B?aytjRGFFd3pnd28wQlZUMkU0R0Nza0U1b1VlUVowOTREOUhONzNIUUtyZWxQ?= =?utf-8?B?Mnhmak1RVFNDeDJCVFdkN3dOUE14M0kyakpGN2V0OTNtVEJUQ0RDakpRU1dQ?= =?utf-8?B?dHRSenl5MHJ1WU02OFpRWjZDVmpwcTJ4R1FBcVhJUEVIM0RqZDlHeklubXha?= =?utf-8?B?OE9hT0JuQVpETnlxQmtqclJ1WnFxclpOSW00ZlNuZlBjR1ltOVJlaTB5b0lq?= =?utf-8?B?WnIwd0RTTDJPelYwaExrZ2NPMVlRY29IVnRqWkJ1VUY3Qm1NTzBEYk5wSlEy?= =?utf-8?B?aVlFRXVKbTB1SnJjZ01pNEloVlhOL1FaWVFJcWV2dDFPWGNlU2orRHN1M3hm?= =?utf-8?B?aWpJQ0dXYXNwRmxwOVlCNUxWakJZQmlBZ0t6Y1VBdG53M29nZHVTSmpkRktC?= =?utf-8?B?SWY2emwzKzdieGhQd0hzNzFOYUNhM1RGeXYvWHFuM2ZLKzF4UW10MVRLMmFV?= =?utf-8?B?aFVUVkhvSFVMSnl1QzZaT1ZKQ2xUTTZYR01NbUZtenVrYTU2QTVwVWViRnFp?= =?utf-8?B?N3A2VDY1RGg3MmZMcVVuVVdRbkJDRWs4eUdwNThXbWMwM0I3bmxiZjE4dkdq?= =?utf-8?B?V1pQUlpHcFhUNXJYc2RrUzdCOW1RZERNbCs5UWk5LytYb0xONVJzU2drSUFj?= =?utf-8?B?NVFkT2J1am1ESjR0VlMvY25DOWlGVi9KN0lSb1pRTGNuTjRDNFA3YnV6bEhM?= =?utf-8?B?d2d2bXhiWnhkOTNNNkx0Q2xjTU1Na3lZc2lpdHc1eXV0UkhhcFNOYVNlVjNU?= =?utf-8?B?eUFxbVRZS0xSYXhneFBSZlh3RE10U1R5QXNKbGM3Ny9Dd2d5dkQybmhiblZN?= =?utf-8?B?ak9mNW1aYUNOZmRHREpWazBTWVlzNmgzQUs0MUVlS2hiOTg4cHhGdjNrMzFN?= =?utf-8?B?VUpKZExQcFlRRDE1Y21QTUJjNU1odVJRaWY3NlJlbGZpdlUxZTV4dEF6bFRT?= =?utf-8?B?R2VQdytEWm5INUFVaGRmaDZKbkp4RmYxcTJQWGZDVVFHMFp2ZjdNNmJUa1JO?= =?utf-8?B?emE2VzY5K3RqMHFSK3Rnc0g2K3RUemhHU2ZuMDZZbDRFKy8xcS9FS3ZBQm9N?= =?utf-8?B?YThXcVRrOEZWV1NOaDFVcEl0cFVuUTJrN1hqeFZFVnRvMFkybFdTOTdyWGdv?= =?utf-8?B?bUgzNzZtTTE3bTVaSERnWFpaRExyUm15ZFhHbFRKSzNUOGQvQmNmSHVQQVls?= =?utf-8?Q?3z8NSYbcNd6Fa0G0/RBH6PkSU?= X-MS-Exchange-CrossTenant-Network-Message-Id: 6506fc20-311c-4536-3103-08dae93a25bd X-MS-Exchange-CrossTenant-AuthSource: CO1PR11MB4820.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 29 Dec 2022 01:15:17.9689 (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: SxdV0AWOlTNv2T9/vJ7r6dtbmgrIaq9YA5xNAc9nd3m0JmiMFH4ZllqpOWHOEx40Xf9iPLmPumJc7HKZY4+6Wg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH0PR11MB5174 X-OriginatorOrg: intel.com X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: BC96BC000F X-Stat-Signature: ttn1ctxbwkb5fzxqygoz13fnzyf9qugp X-HE-Tag: 1672276523-398588 X-HE-Meta: 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 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 12/28/2022 9:24 AM, David Rientjes wrote: > On Fri, 23 Dec 2022, Yin Fengwei wrote: > >> Kernel build regression with LLVM was reported here: >> https://lore.kernel.org/all/Y1GCYXGtEVZbcv%2F5@dev-arch.thelio-3990X/ >> with commit f35b5d7d676e ("mm: align larger anonymous mappings on THP >> boundaries"). And the commit f35b5d7d676e was reverted. >> >> It turned out the regression is related with madvise(MADV_DONTNEED) >> was used by ld.lld. But with none PMD_SIZE aligned parameter len. >> trace-bpfcc captured: >> 531607 531732 ld.lld do_madvise.part.0 start: 0x7feca9000000, len: 0x7fb000, behavior: 0x4 >> 531607 531793 ld.lld do_madvise.part.0 start: 0x7fec86a00000, len: 0x7fb000, behavior: 0x4 >> >> If the underneath physical page is THP, the madvise(MADV_DONTNNED) can >> trigger split_queue_lock contention raised significantly. perf showed >> following data: >> 14.85% 0.00% ld.lld [kernel.kallsyms] [k] >> entry_SYSCALL_64_after_hwframe >> 11.52% >> entry_SYSCALL_64_after_hwframe >> do_syscall_64 >> __x64_sys_madvise >> do_madvise.part.0 >> zap_page_range >> unmap_single_vma >> unmap_page_range >> page_remove_rmap >> deferred_split_huge_page >> __lock_text_start >> native_queued_spin_lock_slowpath >> >> If THP can't be removed from rmap as whole THP, partial THP will be >> removed from rmap by removing sub-pages from rmap. Even the THP >> head page is added to deferred queue already, the split_queue_lock >> will be acquired and check whether the THP head page is in the queue >> already. Thus, the contention of split_queue_lock is raised. >> >> Before acquire split_queue_lock, check and bail out early if the THP >> head page is in the queue already. The checking without holding >> split_queue_lock could race with deferred_split_scan, but it doesn't >> impact the correctness here. >> >> Test result of building kernel with ld.lld: >> commit 7b5a0b664ebe (parent commit of f35b5d7d676e): >> time -f "\t%E real,\t%U user,\t%S sys" make LD=ld.lld -skj96 allmodconfig all >> 6:07.99 real, 26367.77 user, 5063.35 sys >> >> commit f35b5d7d676e: >> time -f "\t%E real,\t%U user,\t%S sys" make LD=ld.lld -skj96 allmodconfig all >> 7:22.15 real, 26235.03 user, 12504.55 sys >> >> commit f35b5d7d676e with the fixing patch: >> time -f "\t%E real,\t%U user,\t%S sys" make LD=ld.lld -skj96 allmodconfig all >> 6:08.49 real, 26520.15 user, 5047.91 sys >> >> Signed-off-by: Yin Fengwei > > Acked-by: David Rientjes Thanks for reviewing the patch. Regards Yin, Fengwei