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 X-Spam-Level: X-Spam-Status: No, score=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,MSGID_FROM_MTA_HEADER,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B6FC9C433E0 for ; Wed, 10 Feb 2021 02:20:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7CF7364E4B for ; Wed, 10 Feb 2021 02:20:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234425AbhBJCUZ (ORCPT ); Tue, 9 Feb 2021 21:20:25 -0500 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:60264 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S234905AbhBJBah (ORCPT ); Tue, 9 Feb 2021 20:30:37 -0500 Received: from pps.filterd (m0001303.ppops.net [127.0.0.1]) by m0001303.ppops.net (8.16.0.43/8.16.0.43) with SMTP id 11A1Rjml022070; Tue, 9 Feb 2021 17:29:38 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=date : from : to : cc : subject : message-id : references : content-type : in-reply-to : mime-version; s=facebook; bh=rvS8m/OZfe3xoVbz9OdPiBteV2pJOn030SHgKciycb8=; b=lG6imbrjtFHdW2Z4B50GSt7EKv8v9t8QsDYb02PEN2zMLOWkOT57kfJ0ACeOR/zt7loe dZjDZLzrEp23LPgUv/jk5S84qd2pNEYnKPdV+tolIfrT0F8xnCiSQfJNpcOq4/JPxbjN Trpy1DZX3wfHZEbI68jdQM0T0iCAuX47VUg= Received: from maileast.thefacebook.com ([163.114.130.16]) by m0001303.ppops.net with ESMTP id 36hqnthuja-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT); Tue, 09 Feb 2021 17:29:38 -0800 Received: from NAM12-DM6-obe.outbound.protection.outlook.com (100.104.31.183) by o365-in.thefacebook.com (100.104.36.102) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Tue, 9 Feb 2021 17:29:37 -0800 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=fNHyzt2ajePis3M6eAdnMcOS74INW1J5/5NF15eabiCvetLwRlWQG6U5gKKu1s7pe8D9Ps43Sxfz1G2VYJ1xZroDMT3pWgxDMVJK32aiQM5qZhqPWS1joyQ/u9rd2+OFJxwsVnhTSG21hgSTPP10anMh6XmyWWG602erxIufEt9RCexwEhaCNjcvIebXlbr4tZmyLkTIt8/BOFvLwsjgxWxKfUDi74wcwiEMJy4lNkykhtzO+2YeIWoHoz8aUdvF0DEu0vCKxm2jp9zW3swu6+V/azr6xAN00ySff3qIL6SICwONywYG0ihOOD6ipHBHMczk0i05cYF2Mix13a3wyA== 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-SenderADCheck; bh=rvS8m/OZfe3xoVbz9OdPiBteV2pJOn030SHgKciycb8=; b=PIYnWB1EvFGaPSOokUN4q7O6iX7MnVB5ahjymAZp+zI5MfG/uL74PZkHzhntpRA4DGRObT1mPbuC3cFkWSigjQaxYGEpk1Fw/1Ree7L4/m9wGtcgiS3pJsdq4bvVuqATSAgo4InFZEIxbRsLGP5tLmE3gUWlzM/rh9QGgp93cveDAT37Pokj43txwWgEbbCElhWnTVEtpb5uJnyeXHCE2+QQKNLICc4Qjcmwg1Mvuv6ngEtJvYIAJSM1EWIxPW1AB91+kqYR0GrYg9Zaa1ae+tHSonAJ/li4Uym5okddGth110oSucnqMCBY3vjqjIWGlDw/W6N0k6QDMIrAybF8Kg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=fb.com; dmarc=pass action=none header.from=fb.com; dkim=pass header.d=fb.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.onmicrosoft.com; s=selector2-fb-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=rvS8m/OZfe3xoVbz9OdPiBteV2pJOn030SHgKciycb8=; b=JgSUJRUkHxDfo18RVmLTSyFF46Nm1vgodSXRR9ibDmXfd6E6dMZkEs20cU1ylShE5EsqclvNUejfkJNsCfHDteHbcAiOU6hCZi1t8aLGCzVFPvqZKuRSznco96bk2FWBB0kRnHEI19AjN5/CfMdDbCNbhjGrwHZwbTAxBAM54T8= Authentication-Results: gmail.com; dkim=none (message not signed) header.d=none;gmail.com; dmarc=none action=none header.from=fb.com; Received: from BYAPR15MB4136.namprd15.prod.outlook.com (2603:10b6:a03:96::24) by BYAPR15MB3350.namprd15.prod.outlook.com (2603:10b6:a03:109::10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3846.26; Wed, 10 Feb 2021 01:29:36 +0000 Received: from BYAPR15MB4136.namprd15.prod.outlook.com ([fe80::53a:b2c3:8b03:12d1]) by BYAPR15MB4136.namprd15.prod.outlook.com ([fe80::53a:b2c3:8b03:12d1%7]) with mapi id 15.20.3825.030; Wed, 10 Feb 2021 01:29:36 +0000 Date: Tue, 9 Feb 2021 17:29:32 -0800 From: Roman Gushchin To: Yang Shi CC: Kirill Tkhai , Vlastimil Babka , Shakeel Butt , Dave Chinner , Johannes Weiner , Michal Hocko , Andrew Morton , Linux MM , Linux FS-devel Mailing List , Linux Kernel Mailing List Subject: Re: [v7 PATCH 06/12] mm: vmscan: add shrinker_info_protected() helper Message-ID: <20210210012932.GP524633@carbon.DHCP.thefacebook.com> References: <20210209174646.1310591-1-shy828301@gmail.com> <20210209174646.1310591-7-shy828301@gmail.com> <20210210002218.GJ524633@carbon.DHCP.thefacebook.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Originating-IP: [2620:10d:c090:400::5:f6e4] X-ClientProxiedBy: MW4PR04CA0249.namprd04.prod.outlook.com (2603:10b6:303:88::14) To BYAPR15MB4136.namprd15.prod.outlook.com (2603:10b6:a03:96::24) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from carbon.DHCP.thefacebook.com (2620:10d:c090:400::5:f6e4) by MW4PR04CA0249.namprd04.prod.outlook.com (2603:10b6:303:88::14) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3846.25 via Frontend Transport; Wed, 10 Feb 2021 01:29:35 +0000 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: ced2486d-eb3d-4a31-2d21-08d8cd6353e8 X-MS-TrafficTypeDiagnostic: BYAPR15MB3350: X-Microsoft-Antispam-PRVS: X-FB-Source: Internal X-MS-Oob-TLC-OOBClassifiers: OLM:1186; X-MS-Exchange-SenderADCheck: 1 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:BYAPR15MB4136.namprd15.prod.outlook.com;PTR:;CAT:NONE;SFS:(376002)(396003)(39860400002)(346002)(136003)(366004)(66556008)(8936002)(4326008)(86362001)(9686003)(66946007)(66476007)(16526019)(186003)(55016002)(478600001)(7696005)(52116002)(6506007)(8676002)(2906002)(7416002)(1076003)(53546011)(316002)(6666004)(5660300002)(6916009)(83380400001)(54906003)(33656002);DIR:OUT;SFP:1102; X-MS-Exchange-AntiSpam-MessageData: =?us-ascii?Q?CKIiY9FL0ha2H2zoBglQW+SIGItkvUSK34BH5rKO6zsW+ygDs+hPu9OvAPbM?= =?us-ascii?Q?d1+umDFI99znFu3lqblTpm1IocRYBHRes5aHhSfSXljamSxWlKZBpL2UnnQQ?= =?us-ascii?Q?vaHgvXDhhWYDVLPZdNvOTr32oH2lYd58alu3t4Ke/dm4Zn8rLSrWhMxThyNb?= =?us-ascii?Q?y23Rh/G8If440DBOcThZmwa3r99b5y5IWofN/4myg2i2Nxgwew1WZWek+dxI?= =?us-ascii?Q?DDul++okVh2Jx3GA5c2rOI/BMEBBJzcE+VIvVEVpBSU80n0z18rmDLukZSfA?= =?us-ascii?Q?74n3GgdXpi/VaDnEeRX1iRQ6fMedAHW3JJTNsINztiiMOTQmXIUrTTi76H3r?= =?us-ascii?Q?zBB43W6p1nyQGu8sHYYWrTOX7bu43Ne3RmCscoUhi1rH2QGHMtrLevM5evp2?= =?us-ascii?Q?V32lNWnhC3ac4Ptxm5cTm59neWmbVpC250Qfo2vlA4VKv1ueMlTZcUpSrroG?= =?us-ascii?Q?vmlvqdpY3RTxbY4O8wNsinxM5PUwEOsRi/6pXarQ6IqupqLouq0mQYMad63O?= =?us-ascii?Q?2v8Ng9c4eEkx+d6T/mlLcdZ8yigjg0vUNhN18kvlwTg+X5kCv3Ik6c5rsALg?= =?us-ascii?Q?351xRdd75hXiuO7EBTMul5pqbsB0ahjhxzIuaBi27qryRSRC9kUtiBHIuyxC?= =?us-ascii?Q?UOWFOpd0isQohQVsf8PzNcNrXuHAKuUu4MkhM8O1CsZRiEkq5VOju139Tbzq?= =?us-ascii?Q?t34C5dCQ0EX3aSfDksuQ74j2tIRbL8qBxso9GQ9xEBhHtN3fRJWFEWcMA0S3?= =?us-ascii?Q?pzxArY/AheoHWBb5Z4jFG+MXd5jR00KrnYX2EY3kTxYr+9OnRJt4W6HzJw0s?= =?us-ascii?Q?xxmVFefTYLwOyJQgi4N2Cg/BEK+hNccEme1mOeeTQMrMq7zdQ6dV0rsSE1Si?= =?us-ascii?Q?3OA1thgXf3Kky/m23Gd1XV/YFfOcjjiSb7q631dUBcOibZtb3uYr8YYQ4CKE?= =?us-ascii?Q?dkTVXh4VdCYMDZj7p4y76h62tcTNyECJF64g+eTixNxx68D55FIyq5bYUURe?= =?us-ascii?Q?cV6TSXzn9lg7qDNNrqvkBUMJWAkLVa+lJVvLQJbtzIsVZjoo7lVf/mDOS1dX?= =?us-ascii?Q?bVGV88qCcl/l2o8gFSXzQAv4881oiFhHfOWqDWQrGA9aKMVy/4xd+at83i7g?= =?us-ascii?Q?u3Ih2w+nK7eVhaiyB6oTx6PAPskk3M2qBGt6+ePnChQ/DrQ7KS9MYABc8IOW?= =?us-ascii?Q?4vVWRk4tkxE5qZUIpdX74x1PbWuTuUXBSuXEhge1BDKoLrXX3pOWULIV1xsE?= =?us-ascii?Q?nAPd3Sk1BIS02jj5nPwPT5sRj1HdikqgfXlcekPjn96Hs4+M3PfRIbjG0FPx?= =?us-ascii?Q?ofpKPFO/uZ+/wec9Avbx/8ZAoT3G2FKpGkXYTgcfEk2d7ldvhQ2ecDg9VsZI?= =?us-ascii?Q?c8/vWaw=3D?= X-MS-Exchange-CrossTenant-Network-Message-Id: ced2486d-eb3d-4a31-2d21-08d8cd6353e8 X-MS-Exchange-CrossTenant-AuthSource: BYAPR15MB4136.namprd15.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Feb 2021 01:29:36.7355 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 8ae927fe-1255-47a7-a2af-5f3a069daaa2 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: jMDDxpLkiKIMGtzDMZfhW/AsFqyzHR0D0XkfwLKJ3SSBqhBMWMmYWIgGgvm5aCA6 X-MS-Exchange-Transport-CrossTenantHeadersStamped: BYAPR15MB3350 X-OriginatorOrg: fb.com X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.369,18.0.737 definitions=2021-02-09_08:2021-02-09,2021-02-09 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 clxscore=1015 spamscore=0 phishscore=0 priorityscore=1501 impostorscore=0 mlxscore=0 lowpriorityscore=0 malwarescore=0 adultscore=0 bulkscore=0 mlxlogscore=867 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2102100012 X-FB-Internal: deliver Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Feb 09, 2021 at 05:07:07PM -0800, Yang Shi wrote: > On Tue, Feb 9, 2021 at 4:22 PM Roman Gushchin wrote: > > > > On Tue, Feb 09, 2021 at 09:46:40AM -0800, Yang Shi wrote: > > > The shrinker_info is dereferenced in a couple of places via rcu_dereference_protected > > > with different calling conventions, for example, using mem_cgroup_nodeinfo helper > > > or dereferencing memcg->nodeinfo[nid]->shrinker_info. And the later patch > > > will add more dereference places. > > > > > > So extract the dereference into a helper to make the code more readable. No > > > functional change. > > > > > > Signed-off-by: Yang Shi > > > --- > > > mm/vmscan.c | 15 ++++++++++----- > > > 1 file changed, 10 insertions(+), 5 deletions(-) > > > > > > diff --git a/mm/vmscan.c b/mm/vmscan.c > > > index 9436f9246d32..273efbf4d53c 100644 > > > --- a/mm/vmscan.c > > > +++ b/mm/vmscan.c > > > @@ -190,6 +190,13 @@ static int shrinker_nr_max; > > > #define NR_MAX_TO_SHR_MAP_SIZE(nr_max) \ > > > (DIV_ROUND_UP(nr_max, BITS_PER_LONG) * sizeof(unsigned long)) > > > > > > +static struct shrinker_info *shrinker_info_protected(struct mem_cgroup *memcg, > > > + int nid) > > > +{ > > > + return rcu_dereference_protected(memcg->nodeinfo[nid]->shrinker_info, > > > + lockdep_is_held(&shrinker_rwsem)); > > > +} > > > + > > > > > > I'd probably drop the "protected" suffix (because there is no unprotected version, > > right?). > > No, actually there is one "unprotected" call in set_shrinker_bit(). Ah, ok. Then it makes sense. Sorry. > > > > > Other than that LGTM. > > > > Acked-by: Roman Gushchin