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 4B401C83F10 for ; Thu, 10 Jul 2025 01:00:33 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 8B92B6B00AE; Wed, 9 Jul 2025 21:00:14 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 842316B00AF; Wed, 9 Jul 2025 21:00:14 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 696226B00B0; Wed, 9 Jul 2025 21:00:14 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 496D36B00AE for ; Wed, 9 Jul 2025 21:00:14 -0400 (EDT) Received: from smtpin10.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 14FDE1A031F for ; Thu, 10 Jul 2025 01:00:14 +0000 (UTC) X-FDA: 83646548748.10.61C8545 Received: from mx0a-00069f02.pphosted.com (mx0a-00069f02.pphosted.com [205.220.165.32]) by imf13.hostedemail.com (Postfix) with ESMTP id 923442000B for ; Thu, 10 Jul 2025 01:00:10 +0000 (UTC) Authentication-Results: imf13.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2025-04-25 header.b=qiOonKhU; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=Nj3RLLoP; spf=pass (imf13.hostedemail.com: domain of ankur.a.arora@oracle.com designates 205.220.165.32 as permitted sender) smtp.mailfrom=ankur.a.arora@oracle.com; arc=pass ("microsoft.com:s=arcselector10001:i=1"); dmarc=pass (policy=reject) header.from=oracle.com ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1752109210; 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=1isr2Y1EHdAvpFTmBv7zi+TKlEKWkdQE6opsa3ysDr8=; b=4AyJqNv4xG8LIN7jAtYRXbpWqzwPj5Cg9+eLBIaRwerlIZNCXjZP4fAyTsEBQuPYpklFO6 072BFBt+tEXyBA56UCoB2RBTLf2ewWxiDX2kufmo+3PJUakaG0zTwVa2AmI2ILHJmjmyEq im8ohpBHijN3ob7ocmA362kNbfvfrQE= ARC-Authentication-Results: i=2; imf13.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2025-04-25 header.b=qiOonKhU; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=Nj3RLLoP; spf=pass (imf13.hostedemail.com: domain of ankur.a.arora@oracle.com designates 205.220.165.32 as permitted sender) smtp.mailfrom=ankur.a.arora@oracle.com; arc=pass ("microsoft.com:s=arcselector10001:i=1"); dmarc=pass (policy=reject) header.from=oracle.com ARC-Seal: i=2; s=arc-20220608; d=hostedemail.com; t=1752109210; a=rsa-sha256; cv=pass; b=sHlhpadMaXJJsHjUqyWMZ/iMGFWYzYk+O3BuvVaUo+X3PS6c2OvGWG2Ig+Ki52pXtLpxV6 Bt0ienUovfMhVIjCmJVct4h08T3beOJsBfNW8yrBTgu4+ttxzmHOH2bmUy3NTqTndzneDx jE09tttNbWCLsGAYdUauWqEZpunYLCc= Received: from pps.filterd (m0333521.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 569NwZdc010431; Thu, 10 Jul 2025 01:00:01 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=cc :content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s= corp-2025-04-25; bh=1isr2Y1EHdAvpFTmBv7zi+TKlEKWkdQE6opsa3ysDr8=; b= qiOonKhUtXC1PBq+AhqDOK5oMh5QUOoqS2U9lOp33COc5OJDYDYlrEqpFB0QDQs4 Z/jXdvItThLBZkSMkzZQVin+AekIHdlb/B9SllvZs0qfqFeEI292S0D+SfoAsvua HIUw/Ck/AODFw/sobfCi7m3suwyyslOlpuKMqDY0wmO3PBnlGFTFNDyWH9LMHiX4 wEgOIVr66kRfDHLxP8UJqn9axtR4imQVU7087gZ/YOwl208IbIQ3U8rMebWAW/wJ meHCUNFYsGIWlOiDRkM06D8MdGLN3juybZVgQoiwBqGiujF10McE3XVFZQCaaQp1 HzaLtUjaiGcJK0T7AmkHsg== Received: from phxpaimrmta03.imrmtpd1.prodappphxaev1.oraclevcn.com (phxpaimrmta03.appoci.oracle.com [138.1.37.129]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 47t2hwg2me-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 10 Jul 2025 01:00:00 +0000 (GMT) Received: from pps.filterd (phxpaimrmta03.imrmtpd1.prodappphxaev1.oraclevcn.com [127.0.0.1]) by phxpaimrmta03.imrmtpd1.prodappphxaev1.oraclevcn.com (8.18.1.2/8.18.1.2) with ESMTP id 56A057IF023666; Thu, 10 Jul 2025 01:00:00 GMT Received: from nam10-mw2-obe.outbound.protection.outlook.com (mail-mw2nam10on2061.outbound.protection.outlook.com [40.107.94.61]) by phxpaimrmta03.imrmtpd1.prodappphxaev1.oraclevcn.com (PPS) with ESMTPS id 47ptgbvxne-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 10 Jul 2025 01:00:00 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=xkZJaktF7VCJ0JBQVWmpX3qLmTnKQ5XXNVV5cRUxxrmbfVNxUcJO3/RPgNEKZptEPRuAA0mbzKGaQ/ISFyo4iW+O4F0w3Aef0ZkyN3VIsb15dioU/FyRdr7YKf7l43fxe0SYs1ljZGoPNel3zjrJ2GAfVfogq+ZJlLM8XkNFQwKdUDYUDARKsYVCRvujuFkCuzgHIVQoq23EfzNgef3KHedkd2Nu+p2G3W19gWWTckYNlRY3UD5AtYLKzEFMAVF+a6GvsVk4lFMlt5zpEGtGRXKVcS7kQi8YUqb2anozZOtipIhr2dWy0/l6FI/d8EXdNjJVHAEUmdvEI1bnHpfqlg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; 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=1isr2Y1EHdAvpFTmBv7zi+TKlEKWkdQE6opsa3ysDr8=; b=wioxe13c1PnhqlNPMWUDpJi/VqRN+FtBptuDLOQYerfcWqxOB15DnyJ3Sog0bxfpHOm5b3vHKrnELcsq0ZT+9wHnHi4VHBdujl3q/F0Tc2ZMusbz4nX7CWnA84OXjz+pqmug8b53og2Lt0BNbssJXpovCpFKYnX7lDv6z5feH6OG/o5yqvN+G+Z77tC57Q8sjYxF4wVvMsSHbz43fDnO0AD31+olv6BVcC6NRVru03TBZUZr4a99pkWgpUoS8KziCXG40/LaJNzPyoYn5MF/5YuYufE94mO6bJtX+VN0e5SstFbFYI9Dwui/BW3CHGKRvsem/1OV0pDwu+j2aVpcwQ== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=oracle.com; dmarc=pass action=none header.from=oracle.com; dkim=pass header.d=oracle.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.onmicrosoft.com; s=selector2-oracle-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=1isr2Y1EHdAvpFTmBv7zi+TKlEKWkdQE6opsa3ysDr8=; b=Nj3RLLoP2a52aDrCfcf13okg1Mxge+iqYWRJKTBwogG/Bwhu6hcLncTPuwdZWLhaE37UmQxd8oNLtuWG8WF8kBJ2D5UyV4X4mh4yfM3e2NX6Is/HuQ4KvMdZaQw26DvcZb6AF4TA9ux1oCo18NeEya0L/ZRMdZWrN+I3TmOtuDU= Received: from CO6PR10MB5409.namprd10.prod.outlook.com (2603:10b6:5:357::14) by DS7PR10MB4832.namprd10.prod.outlook.com (2603:10b6:5:3a6::19) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8901.28; Thu, 10 Jul 2025 00:59:57 +0000 Received: from CO6PR10MB5409.namprd10.prod.outlook.com ([fe80::3c92:21f3:96a:b574]) by CO6PR10MB5409.namprd10.prod.outlook.com ([fe80::3c92:21f3:96a:b574%4]) with mapi id 15.20.8901.028; Thu, 10 Jul 2025 00:59:57 +0000 From: Ankur Arora To: linux-kernel@vger.kernel.org, linux-mm@kvack.org, x86@kernel.org Cc: akpm@linux-foundation.org, david@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, mingo@redhat.com, mjguzik@gmail.com, luto@kernel.org, peterz@infradead.org, acme@kernel.org, namhyung@kernel.org, tglx@linutronix.de, willy@infradead.org, raghavendra.kt@amd.com, boris.ostrovsky@oracle.com, konrad.wilk@oracle.com, ankur.a.arora@oracle.com Subject: [PATCH v5 13/14] mm: memory: support clearing page-extents Date: Wed, 9 Jul 2025 17:59:25 -0700 Message-Id: <20250710005926.1159009-14-ankur.a.arora@oracle.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20250710005926.1159009-1-ankur.a.arora@oracle.com> References: <20250710005926.1159009-1-ankur.a.arora@oracle.com> Content-Transfer-Encoding: 8bit Content-Type: text/plain X-ClientProxiedBy: MW4PR04CA0054.namprd04.prod.outlook.com (2603:10b6:303:6a::29) To CO6PR10MB5409.namprd10.prod.outlook.com (2603:10b6:5:357::14) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CO6PR10MB5409:EE_|DS7PR10MB4832:EE_ X-MS-Office365-Filtering-Correlation-Id: 7f4cad7a-f4a4-4697-3a2b-08ddbf4d16ed X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|366016|376014|7416014; X-Microsoft-Antispam-Message-Info: =?us-ascii?Q?R6yEeZsEm5EfP6fnOhrzdPY0u2ljCPZT5gqa4QKRi6W+a6MmuTD4lYP2A1wD?= =?us-ascii?Q?+XvtK0H9YZ4yMHxP39YL+BPQ1GY+tWvEBKSdPTPAQ41fWJHx+rvaTE5/oSyF?= =?us-ascii?Q?7egdPjjaq3s/l4hY+xOHL9F3jlPxvElOTjQOivLmp+xpjczWzQCBv0z9YlI2?= =?us-ascii?Q?dz8njNiYjmeOHt9Su0o/ovDRQ87jceS7Af2LJbkzaH6Lj1N+v8Wgzq0O0JL8?= =?us-ascii?Q?TpQhpUphI49bLQCYv+ffu0HIGaEwPHHvMLTZ3kWb46aITtbQS5I2HvljRu5d?= =?us-ascii?Q?bunWRXx9kbggZErVpJxMODox9FE7jgORYGPq9A/c/KR0EqeV/dzmuQyreYFG?= =?us-ascii?Q?uIoVq2LfZfGqceSluYBzjngyCNVwLbrT0nSjTlaAGZ2dhMXYVVxqRaG/CUzT?= =?us-ascii?Q?HT+QTv5CW+D9NxrvnYUTvkdT5oWnT18aE3Bd495BVqj+cJXCCtyUsk2DblFz?= =?us-ascii?Q?7rkhxmi6nYxT8IEh9otvSbQE39b6By+bMCppLpTtzQIREDKdKJ6VhQAG8v3f?= =?us-ascii?Q?KFNbKUORoowd7WPHhtQ/z9Pjmul8V2zCaiuGtKc15wrHo1LxHlLLujQTt6p5?= =?us-ascii?Q?NrOH/9zMUzZTEei4w9exfCHAMBAPJinLtZh5GI1ZfStygnbaXaWydqEWL3hf?= =?us-ascii?Q?EjQGaCmaI5V/Q7uw8PYqNdgx7QxgUii0T8A0eAyipTkjdC34gugrlcARWOb8?= =?us-ascii?Q?DBpcJyOBGUzhtUXv6pms41GtQJo/663iKGdDODTaR0/QAICGkgvQg27hQMuO?= =?us-ascii?Q?C5YfYy0Ls3xxBeLyG0AKrc7jGIyZE0D78RBPEFsHwiFPg9TRODJKcnPNMe2O?= =?us-ascii?Q?Q8YROKM8efX5hWXSOOhRW1LoQYCDoK/+m6Woc7ViQwWcI/R6N1EP4KqPlwif?= =?us-ascii?Q?H7zu+g+equGnU0+s/EvIFuOWv1G9/kGvfMphrdu+TPyiCubUznq2twZ6R4IN?= =?us-ascii?Q?11WppjGM5ATAdFRfUlkkBFoMzIeDTG6Hwyf+7KS1WcM0qt4RMiwrUKcRJQNF?= =?us-ascii?Q?l/UT4UeKIGmSKJFYi/bdpboOw7SN/Mmxl6j4kESdVsy1gNwJvqUplKxu4FhC?= =?us-ascii?Q?ixb8ymFDShr8NLBqmL1oS2gQLzDZQY2sRRWuAGiE+6/NLu+F56/h6C5KxspR?= =?us-ascii?Q?Vz7oaS+pPzzZ4yftx0yp39R1NOaVWL7w1/SallxMvrcRfj9XjnPJ8fr7v0WR?= =?us-ascii?Q?jk7rtp1ZkAotXHxxYagW3BBhQFDZ8piC9dXyZh2gn3nOGbd40cmx5xmu70ES?= =?us-ascii?Q?wuhwzD3m2YtxYpwtN7v+k8bN4JnK4Obabr/RvGO1ZZhWeyou4nnjFWt8yyuW?= =?us-ascii?Q?SmH1HSiwsny3JDmQvqrU5Zk4u/wRnCTglTGQxeDp1ybakfUyjgF0tL5ehK+W?= =?us-ascii?Q?4bVnMaZrqST13fdK0peKjji//psP+Tthz6cBQr30Hacg7cXWDzepmrfgGA/e?= =?us-ascii?Q?h1xPH+caiSs=3D?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:CO6PR10MB5409.namprd10.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(366016)(376014)(7416014);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?YcvpMUCfPHQv9EwQzICgwzFdxIplV6yNhBcDwj2W+9vY+GyfI6nUQbuLK7qL?= =?us-ascii?Q?Ya4HMUmGGY0/lVGH7jS+ke+GH5Xoob5t6T1vj0fUSRku72cM/dhgJnqcT4av?= =?us-ascii?Q?GbbGaUZGYQvNPXT1syT31ruZuw7k8L2VSbP0gvWXFzAaGfPr/n2hQ+qbUgG/?= =?us-ascii?Q?c058HEft83VODh5dOwD4vVImfUQwdi8nF2Kh13+XhbdlkCdOCeICmTaUQYa8?= =?us-ascii?Q?wQAZnZEx3RKTCsJQSWw+nIEBUhYQnibhAMxPlbI4nZlN07bBH2XrGe09sE5z?= =?us-ascii?Q?fMJiJMyIdaO5FGD0KvSwhJcbEEUSHBCKSODjMHlS1MoFb6s53GQXxFkTDpUp?= =?us-ascii?Q?R3YmfC0zbNORn0NZ09P+nuY2C/GvYyPFy5KGrRaNawgcB+TOR7shF9W4Mb53?= =?us-ascii?Q?d8ElqFxWYpvjA71zEi5tlq1oRginbUwGqKbh/qZf8jndHT23wzjYQ4AEATJy?= =?us-ascii?Q?jd4dP2KxA1yf53S3Llq9IavTWCX5iILrE+yptWx7qczeq9R1RvA4u1op/W4t?= =?us-ascii?Q?c6L3Ba1XsIdeByYydCvfvVC8b8fEnx4QnmKFNNpxVjJBKZJOIoDk3PX6Ly5Z?= =?us-ascii?Q?ZuN7llHr5yXxMw375okdJ9SSKVcpOD+wd4jXyle1diNyzzhtOImC6DnShPvN?= =?us-ascii?Q?+tOwqz3nJa+23ueA82dXxeYgFbkbILtGRBDf+fYccVeTEQlwDjyUSNEWQLcB?= =?us-ascii?Q?m9M52DMo6xWEZOVQRbcAL34/71SD/NN27AiACUuxvKEURUj/bPYEjJcTxlqW?= =?us-ascii?Q?fDq/G1AqYqluhnglnEA5og2y+jBXagq/ruHP5b0OVFSJQnWg3UxfM3im38tF?= =?us-ascii?Q?9zRs4iBGum64AKrQC199D8pk0pp0jpX8NEvr0TcMJtrfW0wOkY1AaVU8PxwN?= =?us-ascii?Q?HbGJgxVILmC2MmchsPK0Xa3jGI1QMd+57/sA1qxS/2ztrwyPkLiMCSNirTv3?= =?us-ascii?Q?Jo342PodIfmIzNE/WEUmFiGTWuGrP34+HkqBAKSm2DpxHkx5TDz371WmHJzK?= =?us-ascii?Q?vxRJZKtXIdkENL8ojz2KoYlP3mzSJwMiajSWfPZW31TIgQuw4mQEFKhsPYwq?= =?us-ascii?Q?Lmy0SZMfuvMFUWtvK82xi9qh+29niieoEUIAM9AgxV4tEOlZzVmGaunCDZSy?= =?us-ascii?Q?D4v2l2LWb+sZyoQwwgap8+YatCNaoh7Nx7X2cMTXl6MvsdcKASx6VDXI9P2x?= =?us-ascii?Q?6/W964P9RbUhQ/9ddjk5OeuNbgOkD9biB5b3QwMjwgZsbS5ZMM8q59Z6L5pe?= =?us-ascii?Q?giZ5Ddg0+zhERljv4aNJYDdPzwuJ8KZoPzYbGkCllQ7y3WnVeknh21km91/R?= =?us-ascii?Q?UGOA9UZxw+X6H7Sx6MO/WxXnBJ5qDsDpmRDP99nTd4utFVV42wljcWRfPkcb?= =?us-ascii?Q?Rek6t7ZlcUkHViC8gfBfdIlEpkP5UukNqaYI8knSe2oGAfEBuJCNUqTznpeQ?= =?us-ascii?Q?JjgXuPpO9fd9ztyB8CF/arrMHWXrw3UWguiALJ6PvX2+ZKMQc24WrWwnRxV0?= =?us-ascii?Q?vhFkob/42InBsOhB+KPW/uoB3K90QKg1YbzqmU78Ytk+ih8Lzi4wqs3Wnlg7?= =?us-ascii?Q?PURgMc6zyytPPEHErXbMPg2mAHCXcMwAlcBU1OoaggsUCvFu+wThmvB/ozk8?= =?us-ascii?Q?mw=3D=3D?= X-MS-Exchange-AntiSpam-ExternalHop-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-ExternalHop-MessageData-0: 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 X-OriginatorOrg: oracle.com X-MS-Exchange-CrossTenant-Network-Message-Id: 7f4cad7a-f4a4-4697-3a2b-08ddbf4d16ed X-MS-Exchange-CrossTenant-AuthSource: CO6PR10MB5409.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Jul 2025 00:59:57.5687 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: IPqoHNpaUEAGMUFJQng3xoozQEAIezuFCjHsbjdG+kjXoCMzUZkan+A9eVwpw6XTvOA6nmBQQSPeGXufYyerV9MFP/7eDnVp+PQRnBxn690= X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS7PR10MB4832 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1099,Hydra:6.1.7,FMLib:17.12.80.40 definitions=2025-07-09_05,2025-07-09_01,2025-03-28_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 phishscore=0 bulkscore=0 malwarescore=0 mlxscore=0 mlxlogscore=999 adultscore=0 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2505160000 definitions=main-2507100006 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwNzEwMDAwNiBTYWx0ZWRfXykU9HHgHsTwe ewY8qRgMjoC6rRTIUEnDQUKGTlmfCmmABgie68JqJlxUOOliMmjsPOuSBwyud6SIO+N6fXQvW5U qghxh7G9yfhRviscIagVaaIfB7b/Rev18eczHvVlijNTfMCUhx1k6GMM3Gu7CpAV3n4tZY/CbPA bdW7sT/WQRi9+TTWPTf3tgeZpRmANM0ZorHR97T5QdPObQmgVTpMPRJXalxyYSgNcYLD3a0Birr D+ma/uRYYExkcpYAeYjz8LoHf17EXNcda3csZEWEnjxTP66FBoNwPW0ctebw8f42ZBII9GyTVVu ZXk00+5XWGsFihX2fmBqAw+zbaVUVLNd/GKFmdtUMYNVH9etBawAoCZfsSY9bxHFhwjxTYXUZYo NH8DGF1jf79PBoLvJ7PPJ14h/wSzECA949i0ZZNjOuClFEpD8FvPOo9aMqAR9oXl888EGE4N X-Authority-Analysis: v=2.4 cv=BI6zrEQG c=1 sm=1 tr=0 ts=686f1090 b=1 cx=c_pps a=WeWmnZmh0fydH62SvGsd2A==:117 a=WeWmnZmh0fydH62SvGsd2A==:17 a=6eWqkTHjU83fiwn7nKZWdM+Sl24=:19 a=lCpzRmAYbLLaTzLvsPZ7Mbvzbb8=:19 a=wKuvFiaSGQ0qltdbU6+NXLB8nM8=:19 a=Ol13hO9ccFRV9qXi2t6ftBPywas=:19 a=xqWC_Br6kY4A:10 a=Wb1JkmetP80A:10 a=GoEa3M9JfhUA:10 a=yPCof4ZbAAAA:8 a=ikw_7Nr-yr50B0xR4lgA:9 X-Proofpoint-GUID: AS_8F3hhv_C8grmbKTSYuGsoj2Pd0Ur8 X-Proofpoint-ORIG-GUID: AS_8F3hhv_C8grmbKTSYuGsoj2Pd0Ur8 X-Rspam-User: X-Rspamd-Queue-Id: 923442000B X-Rspamd-Server: rspam09 X-Stat-Signature: udkqcbffwwr85ufho15uqs3p9tmigabw X-HE-Tag: 1752109210-702472 X-HE-Meta: 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 O521iEUy 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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: List-Subscribe: List-Unsubscribe: folio_zero_user() is constrained to clear in a page-at-a-time fashion because it supports CONFIG_HIGHMEM which means that kernel mappings for pages in a folio are not guaranteed to be contiguous. We don't have this problem when running under configurations with CONFIG_CLEAR_PAGE_EXTENT (implies !CONFIG_HIGHMEM), so zero in longer page-extents. This is expected to be faster because the processor can now optimize the clearing based on the knowledge of the extent. However, clearing in larger chunks can have two other problems: - cache locality when clearing small folios (< MAX_ORDER_NR_PAGES) (larger folios don't have any expectation of cache locality). - preemption latency when clearing large folios. Handle the first by splitting the clearing in three parts: the faulting page and its immediate locality, its left and right regions; the local neighbourhood is cleared last. The second problem is relevant only when running under cooperative preemption models. Limit the worst case preemption latency by clearing in architecture specified ARCH_CLEAR_PAGE_EXTENT units. Signed-off-by: Ankur Arora --- mm/memory.c | 86 ++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 85 insertions(+), 1 deletion(-) diff --git a/mm/memory.c b/mm/memory.c index b0cda5aab398..c52806270375 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -7034,6 +7034,7 @@ static inline int process_huge_page( return 0; } +#ifndef CONFIG_CLEAR_PAGE_EXTENT static void clear_gigantic_page(struct folio *folio, unsigned long addr_hint, unsigned int nr_pages) { @@ -7058,7 +7059,10 @@ static int clear_subpage(unsigned long addr, int idx, void *arg) /** * folio_zero_user - Zero a folio which will be mapped to userspace. * @folio: The folio to zero. - * @addr_hint: The address will be accessed or the base address if uncelar. + * @addr_hint: The address accessed by the user or the base address. + * + * folio_zero_user() uses clear_gigantic_page() or process_huge_page() to + * do page-at-a-time zeroing because it needs to handle CONFIG_HIGHMEM. */ void folio_zero_user(struct folio *folio, unsigned long addr_hint) { @@ -7070,6 +7074,86 @@ void folio_zero_user(struct folio *folio, unsigned long addr_hint) process_huge_page(addr_hint, nr_pages, clear_subpage, folio); } +#else /* CONFIG_CLEAR_PAGE_EXTENT */ + +static void clear_pages_resched(void *addr, int npages) +{ + int i, remaining; + + if (preempt_model_preemptible()) { + clear_pages(addr, npages); + goto out; + } + + for (i = 0; i < npages/ARCH_CLEAR_PAGE_EXTENT; i++) { + clear_pages(addr + i * ARCH_CLEAR_PAGE_EXTENT * PAGE_SIZE, + ARCH_CLEAR_PAGE_EXTENT); + cond_resched(); + } + + remaining = npages % ARCH_CLEAR_PAGE_EXTENT; + + if (remaining) + clear_pages(addr + i * ARCH_CLEAR_PAGE_EXTENT * PAGE_SHIFT, + remaining); +out: + cond_resched(); +} + +/* + * folio_zero_user - Zero a folio which will be mapped to userspace. + * @folio: The folio to zero. + * @addr_hint: The address accessed by the user or the base address. + * + * Uses architectural support for clear_pages() to zero page extents + * instead of clearing page-at-a-time. + * + * Clearing of small folios (< MAX_ORDER_NR_PAGES) is split in three parts: + * pages in the immediate locality of the faulting page, and its left, right + * regions; the local neighbourhood cleared last in order to keep cache + * lines of the target region hot. + * + * For larger folios we assume that there is no expectation of cache locality + * and just do a straight zero. + */ +void folio_zero_user(struct folio *folio, unsigned long addr_hint) +{ + unsigned long base_addr = ALIGN_DOWN(addr_hint, folio_size(folio)); + const long fault_idx = (addr_hint - base_addr) / PAGE_SIZE; + const struct range pg = DEFINE_RANGE(0, folio_nr_pages(folio) - 1); + const int width = 2; /* number of pages cleared last on either side */ + struct range r[3]; + int i; + + if (folio_nr_pages(folio) > MAX_ORDER_NR_PAGES) { + clear_pages_resched(page_address(folio_page(folio, 0)), folio_nr_pages(folio)); + return; + } + + /* + * Faulting page and its immediate neighbourhood. Cleared at the end to + * ensure it sticks around in the cache. + */ + r[2] = DEFINE_RANGE(clamp_t(s64, fault_idx - width, pg.start, pg.end), + clamp_t(s64, fault_idx + width, pg.start, pg.end)); + + /* Region to the left of the fault */ + r[1] = DEFINE_RANGE(pg.start, + clamp_t(s64, r[2].start-1, pg.start-1, r[2].start)); + + /* Region to the right of the fault: always valid for the common fault_idx=0 case. */ + r[0] = DEFINE_RANGE(clamp_t(s64, r[2].end+1, r[2].end, pg.end+1), + pg.end); + + for (i = 0; i <= 2; i++) { + int npages = range_len(&r[i]); + + if (npages > 0) + clear_pages_resched(page_address(folio_page(folio, r[i].start)), npages); + } +} +#endif /* CONFIG_CLEAR_PAGE_EXTENT */ + static int copy_user_gigantic_page(struct folio *dst, struct folio *src, unsigned long addr_hint, struct vm_area_struct *vma, -- 2.43.5