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 lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B9A8EC7EE23 for ; Fri, 2 Jun 2023 01:59:03 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.542900.847318 (Exim 4.92) (envelope-from ) id 1q4u3t-0005PG-Hu; Fri, 02 Jun 2023 01:58:41 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 542900.847318; Fri, 02 Jun 2023 01:58:41 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1q4u3t-0005P9-Eo; Fri, 02 Jun 2023 01:58:41 +0000 Received: by outflank-mailman (input) for mailman id 542900; Fri, 02 Jun 2023 01:58:40 +0000 Received: from se1-gles-sth1-in.inumbo.com ([159.253.27.254] helo=se1-gles-sth1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1q4u3s-0005P3-Er for xen-devel@lists.xenproject.org; Fri, 02 Jun 2023 01:58:40 +0000 Received: from EUR04-DB3-obe.outbound.protection.outlook.com (mail-db3eur04on0629.outbound.protection.outlook.com [2a01:111:f400:fe0c::629]) by se1-gles-sth1.inumbo.com (Halon) with ESMTPS id fd94c0bd-00e8-11ee-b231-6b7b168915f2; Fri, 02 Jun 2023 03:58:38 +0200 (CEST) Received: from AM5PR0201CA0004.eurprd02.prod.outlook.com (2603:10a6:203:3d::14) by AS4PR08MB7653.eurprd08.prod.outlook.com (2603:10a6:20b:4cf::5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6433.26; Fri, 2 Jun 2023 01:58:35 +0000 Received: from AM7EUR03FT046.eop-EUR03.prod.protection.outlook.com (2603:10a6:203:3d:cafe::a4) by AM5PR0201CA0004.outlook.office365.com (2603:10a6:203:3d::14) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6455.23 via Frontend Transport; Fri, 2 Jun 2023 01:58:35 +0000 Received: from 64aa7808-outbound-1.mta.getcheckrecipient.com (63.35.35.123) by AM7EUR03FT046.mail.protection.outlook.com (100.127.140.78) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6477.10 via Frontend Transport; Fri, 2 Jun 2023 01:58:35 +0000 Received: ("Tessian outbound 8b05220b4215:v136"); Fri, 02 Jun 2023 01:58:35 +0000 Received: from 7980f28d47d3.1 by 64aa7808-outbound-1.mta.getcheckrecipient.com id 7A7A23AF-BD66-4B3A-80C7-4AE51976150D.1; Fri, 02 Jun 2023 01:58:28 +0000 Received: from EUR02-AM0-obe.outbound.protection.outlook.com by 64aa7808-outbound-1.mta.getcheckrecipient.com with ESMTPS id 7980f28d47d3.1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384); Fri, 02 Jun 2023 01:58:28 +0000 Received: from AS8PR08MB7991.eurprd08.prod.outlook.com (2603:10a6:20b:570::15) by AS2PR08MB8832.eurprd08.prod.outlook.com (2603:10a6:20b:5e6::9) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6455.23; Fri, 2 Jun 2023 01:58:26 +0000 Received: from AS8PR08MB7991.eurprd08.prod.outlook.com ([fe80::2db3:aa30:7be0:10a6]) by AS8PR08MB7991.eurprd08.prod.outlook.com ([fe80::2db3:aa30:7be0:10a6%4]) with mapi id 15.20.6455.020; Fri, 2 Jun 2023 01:58:26 +0000 X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: fd94c0bd-00e8-11ee-b231-6b7b168915f2 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=armh.onmicrosoft.com; s=selector2-armh-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=v6HTBq2BtnCXTO9LEis8hpg7lMj2+rcpyw1lBs0GN7I=; b=ygXelLs82LJDaU1A7zKnoiNG5IrTCA5cnuyMVfCO6oPWl8rSLBtlea8w/6FmPuQgJtPQ6hM8szIZsdR5qNa6WlP+/mcuyKmk9hmeO0Oqxpa6x7CxIFL+sbCpQmrmC32CbTVNYsL70B8jPtIQ+xsZqwTRvsygDrGUZeC2e636kgc= X-MS-Exchange-Authentication-Results: spf=pass (sender IP is 63.35.35.123) smtp.mailfrom=arm.com; dkim=pass (signature was verified) header.d=armh.onmicrosoft.com;dmarc=pass action=none header.from=arm.com; Received-SPF: Pass (protection.outlook.com: domain of arm.com designates 63.35.35.123 as permitted sender) receiver=protection.outlook.com; client-ip=63.35.35.123; helo=64aa7808-outbound-1.mta.getcheckrecipient.com; pr=C X-CR-MTA-TID: 64aa7808 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=Ff5UF5Ggr95yP4h6iHogJxyKMFqr9vw8hxZ+4qBQfwP8+h7Bn6+qk1/xnPEYn1GKMvtfYU8t7AjlvPRYol/Vo/Pokh/49H3753tf5vgpxoZz3CTovvcOcMpWqFGoCrpw8uNNtuXKgbZVhWfg0392P6xm6HNXF0/t6WV7qa0u+7bp9nbgICcuk83pkm1pWPqBYDJquY071jKo7Ms0xtIBWs2qfuCII628gBZyzyeitv0cA689aJk5epvR84FQHvzJcXXf4/U7nR6KW4UWEFYwz159r0GiypeMgYNJzzku1VTWAPDA8lEbH3mdrohYvzusek4cktAvIXN/kg20Dg2C8A== 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=v6HTBq2BtnCXTO9LEis8hpg7lMj2+rcpyw1lBs0GN7I=; b=XktVANklJcKKHDVw5ioVMrfXu6nmhQ09XGQKoc3sFDc9AU6DABzzJ3jjQ0xYQyDOAWHS+okNACc7vWET9lqtG39NpcEjOHcEmfez7165KX/aPIKtQUCuIOSk3sNEyJK3L0qGEB9lpYaY5RT7vjjS5861WrGdXX3AxyXtSRar+FSM0u61C9wSO7nMl4m0r5sg7LgnocywsJojSqssydHKt9wAc2hZQtBYhEgN84Qp9RlQ5nqztMKZPupVFGHpJsLt3R4PnhpKiEqESVPEiLjFNG0NGMQ5ed1XM4KnRW/BqTWekdS0i0WkOb2oIfQ5K/GVA8XNO7D1fazpzMDVaEXaRA== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=arm.com; dmarc=pass action=none header.from=arm.com; dkim=pass header.d=arm.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=armh.onmicrosoft.com; s=selector2-armh-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=v6HTBq2BtnCXTO9LEis8hpg7lMj2+rcpyw1lBs0GN7I=; b=ygXelLs82LJDaU1A7zKnoiNG5IrTCA5cnuyMVfCO6oPWl8rSLBtlea8w/6FmPuQgJtPQ6hM8szIZsdR5qNa6WlP+/mcuyKmk9hmeO0Oqxpa6x7CxIFL+sbCpQmrmC32CbTVNYsL70B8jPtIQ+xsZqwTRvsygDrGUZeC2e636kgc= From: Henry Wang To: Vikram Garhwal , "xen-devel@lists.xenproject.org" CC: "michal.orzel@amd.com" , "sstabellini@kernel.org" , "jbeulich@suse.com" , Julien Grall Subject: RE: [XEN][PATCH v7 14/19] common/device_tree: Add rwlock for dt_host Thread-Topic: [XEN][PATCH v7 14/19] common/device_tree: Add rwlock for dt_host Thread-Index: AQHZlOwaX4LVBFA07UiCkT/feXB9lq92wX/Q Date: Fri, 2 Jun 2023 01:58:25 +0000 Message-ID: References: <20230602004824.20731-1-vikram.garhwal@amd.com> <20230602004824.20731-15-vikram.garhwal@amd.com> In-Reply-To: <20230602004824.20731-15-vikram.garhwal@amd.com> Accept-Language: zh-CN, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ts-tracking-id: 0FC1BC7B3E393F4BA3AE2973372BE4F5.0 x-checkrecipientchecked: true Authentication-Results-Original: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=arm.com; x-ms-traffictypediagnostic: AS8PR08MB7991:EE_|AS2PR08MB8832:EE_|AM7EUR03FT046:EE_|AS4PR08MB7653:EE_ X-MS-Office365-Filtering-Correlation-Id: 7341cc02-9da6-406a-09b0-08db630ce023 x-checkrecipientrouted: true nodisclaimer: true X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam-Untrusted: BCL:0; X-Microsoft-Antispam-Message-Info-Original: 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 X-Forefront-Antispam-Report-Untrusted: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:AS8PR08MB7991.eurprd08.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230028)(4636009)(396003)(366004)(376002)(136003)(346002)(39860400002)(451199021)(86362001)(110136005)(186003)(54906003)(71200400001)(478600001)(55016003)(7696005)(6506007)(9686003)(26005)(41300700001)(38100700002)(8676002)(8936002)(33656002)(83380400001)(316002)(2906002)(38070700005)(4744005)(52536014)(5660300002)(66476007)(64756008)(76116006)(66556008)(66446008)(66946007)(4326008)(122000001);DIR:OUT;SFP:1101; Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-MS-Exchange-Transport-CrossTenantHeadersStamped: AS2PR08MB8832 Original-Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=arm.com; X-EOPAttributedMessage: 0 X-MS-Exchange-Transport-CrossTenantHeadersStripped: AM7EUR03FT046.eop-EUR03.prod.protection.outlook.com X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id-Prvs: ac05e5ad-f007-4813-4a7f-08db630cda86 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:63.35.35.123;CTRY:IE;LANG:en;SCL:1;SRV:;IPV:CAL;SFV:NSPM;H:64aa7808-outbound-1.mta.getcheckrecipient.com;PTR:ec2-63-35-35-123.eu-west-1.compute.amazonaws.com;CAT:NONE;SFS:(13230028)(4636009)(346002)(396003)(376002)(39860400002)(136003)(451199021)(36840700001)(46966006)(40470700004)(82310400005)(47076005)(36860700001)(55016003)(83380400001)(40480700001)(336012)(82740400003)(4326008)(81166007)(356005)(41300700001)(316002)(33656002)(7696005)(6506007)(26005)(9686003)(70206006)(70586007)(52536014)(40460700003)(2906002)(4744005)(8676002)(8936002)(5660300002)(54906003)(110136005)(478600001)(86362001)(186003);DIR:OUT;SFP:1101; X-OriginatorOrg: arm.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 02 Jun 2023 01:58:35.3738 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 7341cc02-9da6-406a-09b0-08db630ce023 X-MS-Exchange-CrossTenant-Id: f34e5979-57d9-4aaa-ad4d-b122a662184d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=f34e5979-57d9-4aaa-ad4d-b122a662184d;Ip=[63.35.35.123];Helo=[64aa7808-outbound-1.mta.getcheckrecipient.com] X-MS-Exchange-CrossTenant-AuthSource: AM7EUR03FT046.eop-EUR03.prod.protection.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: AS4PR08MB7653 Hi Vikram, > -----Original Message----- > Subject: [XEN][PATCH v7 14/19] common/device_tree: Add rwlock for dt_host >=20 > Dynamic programming ops will modify the dt_host and there might be other > function which are browsing the dt_host at the same time. To avoid the r= ace > conditions, adding rwlock for browsing the dt_host during runtime. >=20 > Reason behind adding rwlock instead of spinlock: > For now, dynamic programming is the sole modifier of dt_host in Xen > during > run time. All other access functions like iommu_release_dt_device= () are > just reading the dt_host during run-time. So, there is a need to = protect > others from browsing the dt_host while dynamic programming is > modifying > it. rwlock is better suitable for this task as spinlock won't be = able to > differentiate between read and write access. >=20 > Signed-off-by: Vikram Garhwal Reviewed-by: Henry Wang Kind regards, Henry