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 A3760C433F5 for ; Wed, 2 Feb 2022 03:27:05 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C6B8F8D00DE; Tue, 1 Feb 2022 22:26:58 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id C1B6B8D00DD; Tue, 1 Feb 2022 22:26:58 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 9F6DF8D00DE; Tue, 1 Feb 2022 22:26:58 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0085.hostedemail.com [216.40.44.85]) by kanga.kvack.org (Postfix) with ESMTP id 89B178D00DD for ; Tue, 1 Feb 2022 22:26:58 -0500 (EST) Received: from smtpin04.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 4F5EF96768 for ; Wed, 2 Feb 2022 03:26:58 +0000 (UTC) X-FDA: 79096403316.04.29897BA Received: from mx0b-00069f02.pphosted.com (mx0b-00069f02.pphosted.com [205.220.177.32]) by imf25.hostedemail.com (Postfix) with ESMTP id BE00CA0006 for ; Wed, 2 Feb 2022 03:26:57 +0000 (UTC) Received: from pps.filterd (m0246630.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.16.1.2/8.16.1.2) with SMTP id 2120QIZj015788; Wed, 2 Feb 2022 02:42:56 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : subject : date : message-id : references : in-reply-to : content-type : content-transfer-encoding : mime-version; s=corp-2021-07-09; bh=udl56DNLtyTHz/srt+tyNwBTfvWFDlIXimZgRN2PeM4=; b=oeyCLX4mMlkuItQOmf9CIIPZBSyF90C7T4Oz03zdm4LRbsvNETeLQN0geVDSRksfFaQF 7iqdjU/M00zN0mLYeg2eV/tpiE4LYYNh5nh8i7f4GumIWQHFxuQykyimwIQb9cZ1fLRO OWuNd5pzeRkWo7Jo89y7hezDgzrBBNMcOgOxIWe7mrecfZJKR09HAWnaaVYT7ApMsCwo WThcDKpggoEsQf3Gm0S6oXFFjvVTuXOsP3oPe3EzMzdbnP6iJG2NOSMObA94F4dVwHBI qAVSVOWBkeWccxrziq6q2jnlfTdtNXsQJhAkILzSDJ6Q7z8oTJq2w338lNsEfeETAiPx jA== Received: from userp3020.oracle.com (userp3020.oracle.com [156.151.31.79]) by mx0b-00069f02.pphosted.com with ESMTP id 3dxj9wcnwb-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 02 Feb 2022 02:42:56 +0000 Received: from pps.filterd (userp3020.oracle.com [127.0.0.1]) by userp3020.oracle.com (8.16.1.2/8.16.1.2) with SMTP id 2122ZsuA007633; Wed, 2 Feb 2022 02:42:55 GMT Received: from nam12-mw2-obe.outbound.protection.outlook.com (mail-mw2nam12lp2048.outbound.protection.outlook.com [104.47.66.48]) by userp3020.oracle.com with ESMTP id 3dvy1r8aet-6 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 02 Feb 2022 02:42:55 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=Du16nweyiD1QlFxL5zOZHj5J9IfZHaxGkRBL+NJ3kPjV4vMdzJJ6T3LEz0lRt7MhKNOjcXUkr0dgTyCFOHsdQ8qqw1IU4nfMoFh09vqAT1a/ynycwO4IXOz9Ir9KAYuDU4i/98R9qGYj1Sscayb7W4cgcldxKRaAsYf5PCdGhoDkUfqxvYN9zzqzBNKsCs/+6oJ1gCq4b2OHy2ftGvXlqJhnFJa7sDL0qHoKENt3lZZO6IoDbD2O5I9NxGMG/DKWqbypt7jKinbNGTfosTjsbMWmSD0ppJ38M+EwQDPlYt9xMN9ZbMBmx/0PLn2d2tSKPKIayc7GOiHdV8aOSgOPGQ== 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=udl56DNLtyTHz/srt+tyNwBTfvWFDlIXimZgRN2PeM4=; b=GfK3u69GWM48ARKrT/+fRpSYgJN5A/pR4aG4pVRmIoKBIQ0/DeRqR+sxguzw3KC/9PDVUOkkItwepG2739vkUBgJvtmhgXJkQvCHW9HPhruuE6b9bDx5WVCiPUOPfM2YEOC81PTiYD7V4AN2RtL/IiNdq8e+InTTyroRfiQOmlPvoPi/1MpDFggxcyacaVlSxDtpnqWIVYZl8b1R7V90iAh0wcGVi2zVfTxFFwLhmgr7fIf145wN8r3OAfBS74a6dmvPIx+w47VVENkeri65xN+n3vM3zAp/X8Zq3LhPzUn6JXQFQKopckHYzFChusOaY3ARdPCJFRxteSG8YRs3eg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=none; dmarc=none; dkim=none; 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=udl56DNLtyTHz/srt+tyNwBTfvWFDlIXimZgRN2PeM4=; b=wcnsR9npEeyB2UdG2ozYZngnKzH5FneR/uunXF/j3ruB4j4Hu6TxuDQlc807S2kWQv9Nuo/ScwUMJgd8UklGPq10mMnEqX65A0IVkkBlsIqgv53L8YpHzGlI46NDdAWdkUHHBFy4WVmCa7DnxHIo15pBITi1D1NfL2NSbQ3LWWk= Received: from SN6PR10MB3022.namprd10.prod.outlook.com (2603:10b6:805:d8::25) by CO1PR10MB4801.namprd10.prod.outlook.com (2603:10b6:303:96::13) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4930.15; Wed, 2 Feb 2022 02:42:52 +0000 Received: from SN6PR10MB3022.namprd10.prod.outlook.com ([fe80::3857:3a25:3444:fdd3]) by SN6PR10MB3022.namprd10.prod.outlook.com ([fe80::3857:3a25:3444:fdd3%5]) with mapi id 15.20.4930.022; Wed, 2 Feb 2022 02:42:52 +0000 From: Liam Howlett To: "maple-tree@lists.infradead.org" , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , Andrew Morton Subject: [PATCH v5 46/70] ipc/shm: Use VMA iterator instead of linked list Thread-Topic: [PATCH v5 46/70] ipc/shm: Use VMA iterator instead of linked list Thread-Index: AQHYF95+BgCkZZ35OUO+v5crkhoqSg== Date: Wed, 2 Feb 2022 02:42:17 +0000 Message-ID: <20220202024137.2516438-47-Liam.Howlett@oracle.com> References: <20220202024137.2516438-1-Liam.Howlett@oracle.com> In-Reply-To: <20220202024137.2516438-1-Liam.Howlett@oracle.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-mailer: git-send-email 2.34.1 x-ms-publictraffictype: Email x-ms-office365-filtering-correlation-id: d4af3700-3fae-4264-0c22-08d9e5f5b5bf x-ms-traffictypediagnostic: CO1PR10MB4801:EE_ x-microsoft-antispam-prvs: x-ms-oob-tlc-oobclassifiers: OLM:7219; x-ms-exchange-senderadcheck: 1 x-ms-exchange-antispam-relay: 0 x-microsoft-antispam: BCL:0; x-microsoft-antispam-message-info: AbJmauyvPEHu2G9RLGicxp20MRy75aa/BV4wPuXl2aMvrn/8J7V9ThYFBKSVUh5PkG+IKQyYKjQZq7VY43BfB9HvEKECqUQUya8MxsCZMgwoWm0kjjJr8gqzxOdgt76LDlG/8DmIbb+GxtwmGnIC6wZvZ/Av0VKPUkKTzmlCj3iop8CMpnGYHA5MsMTTge+yq4DP6EQ0vB76j9B6nJ02qI+SWKRB9+sU1If4WEL6QSgbn/26MucBzIQmQPV5rDeXi1OF8I1He6KE+ipooLl+CjIyauebk3G6R5GefsaiOFAZUvTpRnazAJa+H1Fu3JVvpjD7ksdA46gxZmOGc2EvUZ1Ma4878fkNaPWzmQYMhZ3DeOQl99+nr+PvPDnDwNb7MVgUuWntvatGalx/QRO2Rz3REU8FarDKUWmj7EtTVzFdL/Fnn+wDLpdcbOoGOMRVXeI4o4oYq5D/lZyx8rScIq8fUNzsy+74cWVsoLr9InLmfBYck43QxaqKtswyZCAjkadNNQUmmbxZ7kh0b7ZOHB+HNyZiflmRyq/2uxcN0WStchnenKJEwa4eT6b1VZHCLytHrMuc8CQUIfqmj9Q0SAlJvLr9TcKhQTXngVNfPy0ogNyWLOinayoaMKyScNCMv+kqMlT6XG6vfxpRWqf2XecL4J4H9+oAbGS+zVo4OeYX9cXNJ0SbjCLyEqPsA3R9/LKptBD1vq27+vvCwNjWXw== x-forefront-antispam-report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:SN6PR10MB3022.namprd10.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230001)(366004)(186003)(508600001)(1076003)(26005)(6486002)(122000001)(5660300002)(36756003)(44832011)(2616005)(6512007)(6666004)(6506007)(83380400001)(2906002)(38100700002)(66446008)(76116006)(86362001)(38070700005)(91956017)(71200400001)(110136005)(66476007)(316002)(64756008)(66556008)(66946007)(8936002)(8676002);DIR:OUT;SFP:1101; x-ms-exchange-antispam-messagedata-chunkcount: 1 x-ms-exchange-antispam-messagedata-0: =?iso-8859-1?Q?75+MS/U9PMGBYvHUNmRDm/Fv+ppEOD5fa3U6/czVbpc/EuReBlAl8Pf/LJ?= =?iso-8859-1?Q?oGz7ZpPq4L20N1DoT+0x+gcVDgfYpbTNYCzgE1hnSjathe0zj5C/E60Zu/?= =?iso-8859-1?Q?AB3xd1gp8Lxku0eV+f6f6KcXjQGzLo0p99HBf/mDpU/Cxm4ZBGmpVEB4UA?= =?iso-8859-1?Q?Z00XRGDfym36UTcy526/2lsINUke3yZw7We59Or4SQ/24yOGIUi0ZzHIAe?= =?iso-8859-1?Q?FEF2Z8L5t+IDJRJoG5S+sRLSvuUldWnDCUy6ar1pRAyv9WXBD81jby1pML?= =?iso-8859-1?Q?eljxX+Wu5BjeFe0m9mX9iueBWr03vIDvP9QxnkyuwcUOWtGyqyPGbYzm7i?= =?iso-8859-1?Q?oDLJll9QRyJh/2gOCxkp7JgAlkhIC6CeeQq+3xUqa5MEE+w65xhloc13vt?= =?iso-8859-1?Q?s4wVjrEUfYXzHFZsUsAgCFZAzT3PeKnVK8ch5HHhhLmS78TpKuewQnjrBd?= =?iso-8859-1?Q?AxrbPfhY/VE1gfTNeUOy16gZHSYD8DAWpbKMaXRM2sOdIzfWnyex0s9UP0?= =?iso-8859-1?Q?2POJ2AiB9deP4ONPZz76BibDTEwas2098Jxh91k+oLsMPTWqxK9zbn6PR0?= =?iso-8859-1?Q?UeMugbQj/jQ/Ov0YpPdZ+p9sT7M1Kmzwt5hMwpdzQNlIR6wkK19eNL6DrN?= =?iso-8859-1?Q?YREUGFA52JFniJzmPdoFp2TpRq3ZnB+KL/gpfl/M+Xjwjd89+pzxCoAYxE?= =?iso-8859-1?Q?wTcHfZSO/yR4sST2euDO8xA8DD/g2r6nMJ92LhjEVTqOtg2xYZdLJwb1XD?= =?iso-8859-1?Q?ug8KYpHGXQZpU6SRuxHdkI48Dg72zxRjEF7Rp2oIt2wpKN8dEhocnSBCq1?= =?iso-8859-1?Q?/cQZ8LJQbt3+22x9GmxegpSKLZDpcplAQ8ljakqgiFloIpHzU/YX13mDSR?= =?iso-8859-1?Q?OYmhYOwNITBv1KNQ6euNILKo6peGbFlw+ZHlQZnGrvX9ughcBxHYqOx5Ci?= =?iso-8859-1?Q?ccUbjdUsAUF3NKjnRPsaZvupTYmkVCVlXeXpeI1xWTNXZm9LTlMdbsWTEy?= =?iso-8859-1?Q?YtEWkyi1pOhBcS1VCVygNIWZdOgJBE8q2+IZuJ6rfboRDoH55ZYmBT/XoM?= =?iso-8859-1?Q?olljoHoI2Bl3j4+0H1oLv/Cyx4fNygs0LHAwga83DEiTnhPKz87jdvjnWK?= =?iso-8859-1?Q?eDJ7iHGfiLjrtCUX2oJ0gP/YptWt7zCK9kghnZhXbcTlecTTjnddDH8Y0a?= =?iso-8859-1?Q?m+m0Gbki7ZAXZYXNnYG9Mw0mLe/O/aaatQ63Rl/A0pvx48ZhUHncA42+UW?= =?iso-8859-1?Q?AYArSk4oGVvgHtXL9omZbmHK+4V5af8DSprzly/OTGY9z7tmQIlyc+yzGH?= =?iso-8859-1?Q?ERLMHjQsj07xrOrmECFep0OF5tMwYBXDhi2WRxtW/sVYC3RAoUiErr2PBH?= =?iso-8859-1?Q?lBC0VbH/Mri//m14oGxQLXuU2FDlQysnjXtRnIGseRF75toGlM2adbk62o?= =?iso-8859-1?Q?sthZ8vDCbzNTTl5D4d74XVaQNxRTC0wneFYwzmzLIouK/unpI4GERdE+vE?= =?iso-8859-1?Q?yvn3mse9+9CuaxDnT1rd6XjBnlMhgk2bdMh83CVpKNoiRJqMSv3AmG1T48?= =?iso-8859-1?Q?nTJF+eXSV61sf91L8JwNo+WJi56kH414KsmbU9JMONUCW7USDvD3KDrVHO?= =?iso-8859-1?Q?QsL7MuQsAdPSlEwueXlEUttximzVoyIRwBZbVxXrHMfqHLgXLbvF8RgF0j?= =?iso-8859-1?Q?J7ZIGVWwPr7ceQiGK88=3D?= Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: oracle.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: SN6PR10MB3022.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: d4af3700-3fae-4264-0c22-08d9e5f5b5bf X-MS-Exchange-CrossTenant-originalarrivaltime: 02 Feb 2022 02:42:17.4698 (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: pQ/5USEviTdfJvGrMDhzmSdjeOiihf1KI/zpVf13RNmKzttjZWogXv9nmLDjPYUJtiTqwCw8BMlPSL4aV1C1SA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CO1PR10MB4801 X-Proofpoint-Virus-Version: vendor=nai engine=6300 definitions=10245 signatures=673430 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 mlxscore=0 spamscore=0 bulkscore=0 adultscore=0 mlxlogscore=999 phishscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2201110000 definitions=main-2202020010 X-Proofpoint-ORIG-GUID: 9IQhDarjRR1kWNRiAqw-rK3JCi8UpunV X-Proofpoint-GUID: 9IQhDarjRR1kWNRiAqw-rK3JCi8UpunV X-Stat-Signature: uu6jcji37xdjjxhxji6n1pxp149ydq1h X-Rspam-User: nil Authentication-Results: imf25.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2021-07-09 header.b=oeyCLX4m; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=wcnsR9np; spf=none (imf25.hostedemail.com: domain of liam.howlett@oracle.com has no SPF policy when checking 205.220.177.32) smtp.mailfrom=liam.howlett@oracle.com; dmarc=pass (policy=none) header.from=oracle.com X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: BE00CA0006 X-HE-Tag: 1643772417-31499 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: From: "Liam R. Howlett" The VMA iterator is faster than the linked llist, and it can be walked even when VMAs are being removed from the address space, so there's no need to keep track of 'next'. Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Liam R. Howlett --- ipc/shm.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-) diff --git a/ipc/shm.c b/ipc/shm.c index b3048ebd5c31..7d86f058fb86 100644 --- a/ipc/shm.c +++ b/ipc/shm.c @@ -1721,7 +1721,7 @@ long ksys_shmdt(char __user *shmaddr) #ifdef CONFIG_MMU loff_t size =3D 0; struct file *file; - struct vm_area_struct *next; + VMA_ITERATOR(vmi, mm, addr); #endif =20 if (addr & ~PAGE_MASK) @@ -1751,12 +1751,9 @@ long ksys_shmdt(char __user *shmaddr) * match the usual checks anyway. So assume all vma's are * above the starting address given. */ - vma =3D find_vma(mm, addr); =20 #ifdef CONFIG_MMU - while (vma) { - next =3D vma->vm_next; - + for_each_vma(vmi, vma) { /* * Check if the starting address would match, i.e. it's * a fragment created by mprotect() and/or munmap(), or it @@ -1774,6 +1771,7 @@ long ksys_shmdt(char __user *shmaddr) file =3D vma->vm_file; size =3D i_size_read(file_inode(vma->vm_file)); do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start, NULL); + mas_pause(&vmi.mas); /* * We discovered the size of the shm segment, so * break out of here and fall through to the next @@ -1781,10 +1779,9 @@ long ksys_shmdt(char __user *shmaddr) * searching for matching vma's. */ retval =3D 0; - vma =3D next; + vma =3D vma_next(&vmi); break; } - vma =3D next; } =20 /* @@ -1794,17 +1791,19 @@ long ksys_shmdt(char __user *shmaddr) */ size =3D PAGE_ALIGN(size); while (vma && (loff_t)(vma->vm_end - addr) <=3D size) { - next =3D vma->vm_next; - /* finding a matching vma now does not alter retval */ if ((vma->vm_ops =3D=3D &shm_vm_ops) && ((vma->vm_start - addr)/PAGE_SIZE =3D=3D vma->vm_pgoff) && - (vma->vm_file =3D=3D file)) + (vma->vm_file =3D=3D file)) { do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start, NULL); - vma =3D next; + mas_pause(&vmi.mas); + } + + vma =3D vma_next(&vmi); } =20 #else /* CONFIG_MMU */ + vma =3D vma_lookup(mm, addr); /* under NOMMU conditions, the exact address to be destroyed must be * given */ --=20 2.34.1