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 9A52BC433F5 for ; Mon, 4 Apr 2022 14:51:53 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id BAA908D0020; Mon, 4 Apr 2022 10:36:43 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B07558D001D; Mon, 4 Apr 2022 10:36:43 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8BDFC8D0020; Mon, 4 Apr 2022 10:36:43 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0225.hostedemail.com [216.40.44.225]) by kanga.kvack.org (Postfix) with ESMTP id 735168D001D for ; Mon, 4 Apr 2022 10:36:43 -0400 (EDT) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 3A206AC030 for ; Mon, 4 Apr 2022 14:36:33 +0000 (UTC) X-FDA: 79319447466.28.1E52957 Received: from mx0a-00069f02.pphosted.com (mx0a-00069f02.pphosted.com [205.220.165.32]) by imf02.hostedemail.com (Postfix) with ESMTP id 72F9080034 for ; Mon, 4 Apr 2022 14:36:32 +0000 (UTC) Received: from pps.filterd (m0246617.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.16.1.2/8.16.1.2) with SMTP id 234DlFTM024455; Mon, 4 Apr 2022 14:36:31 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=KilEw5Md/nyyIMGJ4W124Qy8/yQ2ObLbHRJb+FkZrVVXLwA/pK8odaJs12F98MKR+Cuq 0ojvbxru3egaL275QC6N9Y4HrimSYR/mO+Bu2CmsuE1Nh9sjrQiwGggR/Q9x96P6DRsY dHtMGpOxqa2r50oQRmwE3kgWYEnxZoxLetBZRdxtec+yE2ee0iAcJNLeIttH11MFDa63 OB6BeVK5FdZ46LuW4PooMT2oxQ3W2Ocxd/whmfsTmhhIkqP67yRkgjAVZbEdILHKky2J TMdVyVl2CZcCraNp/cLXBLwSO/kTO6/l3iDPMvlpTWbgqGTLTe9EAi8sEN3NV5dFaj6I Ug== Received: from iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta02.appoci.oracle.com [147.154.18.20]) by mx0b-00069f02.pphosted.com with ESMTP id 3f6f1t3cvh-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 04 Apr 2022 14:36:30 +0000 Received: from pps.filterd (iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com (8.16.1.2/8.16.1.2) with SMTP id 234EGceX027671; Mon, 4 Apr 2022 14:36:27 GMT Received: from nam12-bn8-obe.outbound.protection.outlook.com (mail-bn8nam12lp2176.outbound.protection.outlook.com [104.47.55.176]) by iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com with ESMTP id 3f6cx2gn97-5 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 04 Apr 2022 14:36:27 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=HJTDKnfJ7IFpkFBDJ/Gzmg7Q8joyL6O4i75YpWH2Z6Sqww38lNc0iy8c+/Pm3W0TQDks8SW7YdJDwR+siu0WBXJXRIY+e1P3zdG5au3AbNCzUq9YqZQWDFWkoMxpOfimj56ZXgBAHq1+9mQ83l5IRKxJB8dCyDUQNiVaueHY6d6gbvEf39KJlt9JrHc0osyg/NFNZrvrM5/rrxvkCh11WBR1w2qmT4V4YQveeTKEowOvhNcg6GJt/BtSaJcXqyz5lyTvmzCnKEe+XLRUqWxTxtVYOQxBbR+OrpSDL60/gdGcaGqb+oE+n7yW4UHESLwvl19YJVr88eEVSbWf8INfaA== 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=O/FEkBwOcqaSLeSCmHbMGl5EoY5pK5u79qWFgJmi2TLPXrlhLmzaLxgQSHU5FN8PckbHBhN3gKFPvxpmZvjpMyb9cMTHsV1kXE1tdn9EK8hkKdpQyrtkwXAsu/1H93LCLrJtywAUSpxCQahZHGdLtIfZ2XcKv7TvJtxPkTCy05Uox69k4UKmTTr0zXhsxxn0hLiN5PHmpMxIXuMgDlUeRcyWsIlGaxljx6Dt+hOFgGaECz4katQLoC61vIV1ZYGT19SMCzAFQ0xqTpUIPj0cr1UWp+s1he0oivzSD40MrDUlHLFNWwCEd9tZAg+dFVAizjFQzn9AUGB1uDVqD78iug== 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=udl56DNLtyTHz/srt+tyNwBTfvWFDlIXimZgRN2PeM4=; b=uKCWSAzfKPZUz3ok0M9yucaDHEtob1JJuAhQLSagRsPOtwUjf8/xl9S8HpXMcu3MSwL8awhS24qSMJCc5ctfESWpVqzjs/zWAqov3QN4UeGJjm0fpamG/1kSRlVrcVkmTKLGgqOOl2NnQAHbgaFRrYI7o67RUF+eOMTQIj6bRRo= Received: from SN6PR10MB3022.namprd10.prod.outlook.com (2603:10b6:805:d8::25) by BLAPR10MB5329.namprd10.prod.outlook.com (2603:10b6:208:307::24) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.5123.31; Mon, 4 Apr 2022 14:36:26 +0000 Received: from SN6PR10MB3022.namprd10.prod.outlook.com ([fe80::74fd:df41:4c93:24a5]) by SN6PR10MB3022.namprd10.prod.outlook.com ([fe80::74fd:df41:4c93:24a5%6]) with mapi id 15.20.5123.031; Mon, 4 Apr 2022 14:36:26 +0000 From: Liam Howlett To: "maple-tree@lists.infradead.org" , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , Andrew Morton Subject: [PATCH v7 46/70] ipc/shm: Use VMA iterator instead of linked list Thread-Topic: [PATCH v7 46/70] ipc/shm: Use VMA iterator instead of linked list Thread-Index: AQHYSDFID5Y0Mb9m3Eud8kOf1yoQwg== Date: Mon, 4 Apr 2022 14:35:51 +0000 Message-ID: <20220404143501.2016403-47-Liam.Howlett@oracle.com> References: <20220404143501.2016403-1-Liam.Howlett@oracle.com> In-Reply-To: <20220404143501.2016403-1-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: 352d23b9-63eb-40e6-d2d4-08da16487faf x-ms-traffictypediagnostic: BLAPR10MB5329:EE_ x-microsoft-antispam-prvs: x-ms-exchange-senderadcheck: 1 x-ms-exchange-antispam-relay: 0 x-microsoft-antispam: BCL:0; x-microsoft-antispam-message-info: YD459PxsT6+3cNSQ7YAh8ibU8wKib9Ou8sFlOyKvFvHa6uWkkeefiLSzAeS0xdJ33eIBj0FWAU82cPwMP1mBeH3kbSt4hANq8pXoDsUjdfrYOkeERiNDymPM3cWQ3tLYohjv9o3rDk6cs91r3uJ1KsAmWKWiqmLINwcsyYSemRWGvTrDKtpvvFMC//8rEJFuG9qTuvqcEGatVqVn52lG+FggMQ0899rm+9LIhsGoUSKmiowSlqMZLO5ZTcIBzbtllzFYbwrCBr7MFZ/zLHQV6I09K+BZ1K3a4tFlqLvLdlI6wvnwOy3gdihy11j18FLNvTt7gLT4FCUwPL3dQO1zAeH5Ntg6SthltUsnvLL6bKQ8bJI2fm/s5CV+rl+7laGn441d2ev7DcH8eT/NeE+gzVk2Zb20dVWC/g/XO7O/kR0Nb+nlXf7TWANHcWW/EoBba79hNc+Som5YpehZrsW4U3ZAt7SImRfY6vqPmrwQoLPpLUU+MMJNzIXTjcR6wEnV2bwApn8aNFXGZyCEos0pSoQ/0Vg2OIQCCsn4M0m4U4yIZA1itsdxI2ui0Ouibs21kiWWdtcR+LGFCniPEGJzgun2HEDV0aNgqR98a8oiiNi0y7xZ7vp9zCc9skpQCYu+0nh0jFoAUivWVFA5Es+/2mEdipeQbC4juE1PfUtz6qs5jfBC/kTr8Ar3c/6RmvOin123MqYRZCftHxyY1KRApg== 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)(508600001)(6506007)(64756008)(76116006)(66946007)(66476007)(66446008)(91956017)(316002)(83380400001)(38100700002)(66556008)(6486002)(110136005)(38070700005)(86362001)(71200400001)(6666004)(6512007)(122000001)(44832011)(26005)(2616005)(1076003)(186003)(8676002)(8936002)(36756003)(5660300002)(2906002);DIR:OUT;SFP:1101; x-ms-exchange-antispam-messagedata-chunkcount: 1 x-ms-exchange-antispam-messagedata-0: =?iso-8859-1?Q?H9LU2q9B+uIdLQpTFyLWvO7aIR8+r6g6UMLpDg0F1EowtKgSKOQJxE2uvW?= =?iso-8859-1?Q?XjiMF6q7/9DKx8ycIfzR8ITYedFVk4skZ09p8CriKspcQJ9gWDxJOfxQVy?= =?iso-8859-1?Q?Uju02rp1waitlOGvlxoo18nMuh5uK5dW8mnmn+5w7Aj8w+rikSLaPZyh/p?= =?iso-8859-1?Q?3hL++XLO5P9058fIHYjRBQnem9PJepPwfPxxJYMcz5pdeQ380fEvspHa2M?= =?iso-8859-1?Q?8u12+EegU0uuzKlP3hgNfY/X1xtM9PNv4VNQHUNULFKfI6QnCzHlvSZywN?= =?iso-8859-1?Q?EMDbQc5Z4YJG0EGZES+YJ8XGj/4NgZOBg6zMK2hJk5Ic3jEFF7kz4vrTtl?= =?iso-8859-1?Q?kvhnHMcbHOLQylugnNFN4dvMATHKDuF5TbuX02vZ9AsuBGqOee2HcpzsyS?= =?iso-8859-1?Q?notRrEK4nm/ch3MCvFm0nmVNY03wx9BmJ3UE/EQO7wXrE7lGKXYEGxzsQK?= =?iso-8859-1?Q?qjetDTE6FO2VFAnW5IBZ7yCeVy+QcvD+gD/MHUfG1G0s3yNvVfTtKiyyO8?= =?iso-8859-1?Q?X6sJzM2s4IhGUdTM9U1x0zxdjGmtsBGxKwwO22X+kPBsPVli1CRqPKzoFH?= =?iso-8859-1?Q?39DXQejyxP53LEqZWoxaCz+SCJyG7HpibPmonHo5jWXR4WLpP8zIjI9q6y?= =?iso-8859-1?Q?vZW7gNxpx9VkjDDhadpvLQF/EHIjyzdnx+qd2VvD/Uiv+yq2wgGw3HNVY2?= =?iso-8859-1?Q?AKxcy3Nx53UQEEoJ4FHnAYjMMti340z/cAGlUhy25u6RYStT0LhOO/mD74?= =?iso-8859-1?Q?m/lngsdXEXPDXnJQFaguomMeZCBZS9r+aYYlAs/s462KbBsN31v3cpP37U?= =?iso-8859-1?Q?NuyVEKFbiJJTqkaIHYQzrG3R7OiVXnehnmVWpoIcUMBzdh7e00nxJ90ZGq?= =?iso-8859-1?Q?S+gl8353I4G/+9zebuTkkLiwgoYNPK9SMQAUcwqWoQvuKKS1VhNo4oPjtQ?= =?iso-8859-1?Q?aBsWABKMbJGCPly82g4kc+WU2qv2y2AakUUG8vjDuvta2NS8MXSkO861QB?= =?iso-8859-1?Q?RryajqGqbhd61ZMlmOS3nER8RfAPLYtu2SYX8pj5Lm81/iNac1FwlyZNzS?= =?iso-8859-1?Q?ugynfzKfCgnX/sa6+n/lXcU3C+lSjzFXCrxpU9x1K+0GVV86fuoHSdTbfR?= =?iso-8859-1?Q?0VGtcDKhSMvzZqNPPRIaGSDAktMnGC+IAB2hle4ofNaNuoAydOJrGw6xvI?= =?iso-8859-1?Q?V/nGK3uJBmqglWvtv6pYNiHtx729AK3au1n+DCVvfZ4sJzqGORQ1QKRCeN?= =?iso-8859-1?Q?ckMygRlYNNCt2rSKHzI2cpk6h8qSlys6pKcr/9bmu55RWaSxYpdzXHi4zm?= =?iso-8859-1?Q?kheU9R6rxS9l+8DbwABCHKpDxUkXaik9jogaQk6yRGHQysxzDRgDrYKvd8?= =?iso-8859-1?Q?NOL7cPYKv3DDjlE96gjg2ZzWwrF+hzvR5WzXCvyTYa8KiGzg0Rjwotuqwa?= =?iso-8859-1?Q?5bOw3ZtZNbiq56pKhZhq9q0H96F+SS9DylU27bfip3eGMGewzFduFSiaiR?= =?iso-8859-1?Q?7rzOKxumAr54jEHJcA8RPyRof3GOEHVsCo2zuxsAQTrcz6isg/lBY8+Z5p?= =?iso-8859-1?Q?tkUHC9o3ChGNdc9kTe7yHoZLbphdUiQAbNIfA/nr57wwtfbrHMtDRD0fdh?= =?iso-8859-1?Q?82XWkiITPxHiPJMYIaOSjQ5zvqSB5yXgFUo6fHQyYUYrgG0hiCs57wRaAR?= =?iso-8859-1?Q?ONNDl2Nf9md8QVl3ZJOr+/29Jco85QtaTAeev6b1f4yO/YEc14nFypcQ6m?= =?iso-8859-1?Q?0BTgtQ/8Hz3dapFWHAAIb5VUjwguqLH/UN7zDr5XmtPh2GKIi0xKlR79P1?= =?iso-8859-1?Q?p8rHPWf0POIDo5W9IooK7DmhAIsBVFs=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: 352d23b9-63eb-40e6-d2d4-08da16487faf X-MS-Exchange-CrossTenant-originalarrivaltime: 04 Apr 2022 14:35:51.1743 (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: Ghto4EY2g3iuv6D+Ew1K4PUH/rv1n6tsELlYzTs5S6/oaekNr3cmPR7+luLEhJeqsGINIiMdLnWVKOtAKtku9g== X-MS-Exchange-Transport-CrossTenantHeadersStamped: BLAPR10MB5329 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.425,18.0.850 definitions=2022-04-04_05:2022-03-30,2022-04-04 signatures=0 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 malwarescore=0 spamscore=0 adultscore=0 bulkscore=0 mlxlogscore=999 phishscore=0 suspectscore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2202240000 definitions=main-2204040082 X-Proofpoint-ORIG-GUID: KYHYUiGAbFQ9K4w8_KegJhe8aWk9PeVA X-Proofpoint-GUID: KYHYUiGAbFQ9K4w8_KegJhe8aWk9PeVA X-Rspam-User: X-Stat-Signature: 44ehpoz3koa8gypbwwmiut86xin1pg7n Authentication-Results: imf02.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2021-07-09 header.b=KilEw5Md; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=uKCWSAzf; spf=none (imf02.hostedemail.com: domain of liam.howlett@oracle.com has no SPF policy when checking 205.220.165.32) smtp.mailfrom=liam.howlett@oracle.com; dmarc=pass (policy=none) header.from=oracle.com X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 72F9080034 X-HE-Tag: 1649082992-232188 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