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=-7.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MSGID_FROM_MTA_HEADER,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 37B7BC433B4 for ; Thu, 8 Apr 2021 17:28:22 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6700C610CC for ; Thu, 8 Apr 2021 17:28:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6700C610CC Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=virtuozzo.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:39312 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lUYS4-0002KR-0i for qemu-devel@archiver.kernel.org; Thu, 08 Apr 2021 13:28:20 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:33354) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lUYQC-0001Gf-0u; Thu, 08 Apr 2021 13:26:24 -0400 Received: from mail-eopbgr150138.outbound.protection.outlook.com ([40.107.15.138]:17315 helo=EUR01-DB5-obe.outbound.protection.outlook.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lUYQ1-000739-5d; Thu, 08 Apr 2021 13:26:22 -0400 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=Ni0OF8Sh8eqUc6/XtK9jCFxPIg7e236kF1a+UxLQgujDaJ5x6QJU9hVXLvVOtUNl4eUSq6t7Py06WMavuDjGmRSEDGBCZ810FBUXuCn8iTu5meCQyYLbtjAGz58EXNHZZoT260eF/zluOTeXred5XLiEdAIADJyRmc1Phl6Rvj4leP0IRz/yNt9aRfm4DN4QEemdBfc2vLm6zd8hpTUXhYK/EdjmWNCcEfiyUC6UsurscTJp9iagbRgo8ltKZKMRL6t/OP9bvonmA/M9tv/jnu4OA+rR78DPe06uNliyroYrb3ZylxOmT6mopK4gKB6/8qSLV774q1mC7dcEdk+ofg== 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=YIsRrgEJtbX3jgwvHf8vCRxcsQJYr2Rss5xV+O1Jyig=; b=Rs5wXVapiCr6uaVqDSSSIW2In4BDU4AV7xXZBakHpwxomWHl7eASRwjyzNagWrfTlfij2tSF+YeE6YYCxz6/GsPr5w1RFSO8Iq5GRcezQAsIvRN6dhTOQRQk32eHf3FhIgnW5Npbvf90WSLX5mZP4bxYUI7t+6RSNFotIV0/zei9PsD3UdS9XZc4no/kB2klKL+8xPslFkVCkLDEj2oY8Johk4j2o4t0wevXWs3EgJb2jhn8Z/kMTMjIib8Op5SZFH08LllyqXN7N8x8ojB2PmeDBjZFX/OTBzO8IIO+KKvlRLCmyPexkxQI9V9pDLYeUVrV/MeoJMXUWqJEZnlvFA== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=virtuozzo.com; dmarc=pass action=none header.from=virtuozzo.com; dkim=pass header.d=virtuozzo.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=virtuozzo.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=YIsRrgEJtbX3jgwvHf8vCRxcsQJYr2Rss5xV+O1Jyig=; b=CXyE7oeaOvKLzL+KSbkkvdIERQq0LTOcJxLgibXimu6bvb6xaEplnAaVQZ0orqI2lOvYVM2KIpbrQg4dYtW3vGJUNdNbi4ITJF6OjexSpGgE+getUx1rto8MulygCiSj5e/WF2ey7XG9d6y2gxECFWiTvNrG+OxHVRdN1CRvlFg= Authentication-Results: redhat.com; dkim=none (message not signed) header.d=none;redhat.com; dmarc=none action=none header.from=virtuozzo.com; Received: from AM7PR08MB5494.eurprd08.prod.outlook.com (2603:10a6:20b:dc::15) by AM5PR0801MB1651.eurprd08.prod.outlook.com (2603:10a6:203:39::21) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4020.17; Thu, 8 Apr 2021 17:26:09 +0000 Received: from AM7PR08MB5494.eurprd08.prod.outlook.com ([fe80::b403:c1a9:6bb7:133]) by AM7PR08MB5494.eurprd08.prod.outlook.com ([fe80::b403:c1a9:6bb7:133%7]) with mapi id 15.20.4020.017; Thu, 8 Apr 2021 17:26:09 +0000 Subject: Re: [PATCH for-6.0? 1/3] job: Add job_wait_unpaused() for block-job-complete To: John Snow , Max Reitz , qemu-block@nongnu.org Cc: qemu-devel@nongnu.org, Kevin Wolf References: <20210408162039.242670-1-mreitz@redhat.com> <20210408162039.242670-2-mreitz@redhat.com> <505ba75a-996b-0c65-0c49-add50e55e3ce@virtuozzo.com> <66c60724-d3b5-383b-7a19-9e9498e1c132@redhat.com> From: Vladimir Sementsov-Ogievskiy Message-ID: Date: Thu, 8 Apr 2021 20:26:07 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.9.0 In-Reply-To: <66c60724-d3b5-383b-7a19-9e9498e1c132@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [185.215.60.206] X-ClientProxiedBy: FR2P281CA0010.DEUP281.PROD.OUTLOOK.COM (2603:10a6:d10:a::20) To AM7PR08MB5494.eurprd08.prod.outlook.com (2603:10a6:20b:dc::15) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from [192.168.100.8] (185.215.60.206) by FR2P281CA0010.DEUP281.PROD.OUTLOOK.COM (2603:10a6:d10:a::20) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4042.8 via Frontend Transport; Thu, 8 Apr 2021 17:26:09 +0000 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 3142f506-952a-41f6-1b16-08d8fab36639 X-MS-TrafficTypeDiagnostic: AM5PR0801MB1651: X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:10000; 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:AM7PR08MB5494.eurprd08.prod.outlook.com; PTR:; CAT:NONE; SFS:(4636009)(136003)(346002)(39840400004)(396003)(376002)(366004)(38100700001)(2906002)(110136005)(38350700001)(66946007)(5660300002)(316002)(8936002)(6486002)(2616005)(8676002)(36756003)(956004)(16526019)(66556008)(66476007)(86362001)(186003)(31686004)(52116002)(83380400001)(478600001)(26005)(16576012)(4326008)(31696002)(53546011)(45980500001)(43740500002); DIR:OUT; SFP:1102; X-MS-Exchange-AntiSpam-MessageData: =?utf-8?B?NW1nZlFiM2xJb1N0VUtvK1EwcEt6NHdmNkU4Vm1TS1hVRFo3WC9BQS9ySU9n?= =?utf-8?B?SG1NV2ViMEt4eXpaU2pMREp0dXl1NGhQQ2UwMmxKaWNrcnJwem54UUlhR3FX?= =?utf-8?B?Y3loNXBLWEY5cWR4U1VXYmJ1cTQ3MXdwd0sxeW52WG81QkhhUFlKeXlBYlRE?= =?utf-8?B?VS9jZmhVOXk2R3dQenRpN284V01rZ1dTamg3OUJxUzVUeHdkMno1Y3pXQWts?= =?utf-8?B?QlI1UnFjWDdhUlZLVEp2eDZTQVZsOWYzSTdvM3ZPa0szQUFHdVZXcHN6SzQ3?= =?utf-8?B?a3g4cTNUd2luYzl3a1VaNzV4MWFTektVcDZPOGVGK0xFV2JyWEV4T3lsU0xT?= =?utf-8?B?YVkrVkpQNncwdVhrYnJZUkEvRndTUkhCV0dmQ1ZYNWF6UEM0RUFjclVxc1VR?= =?utf-8?B?eTFLTFJWYTN1WHFOdlJUZG9UUlA3UTJXaFJNMTNkbG1BNVliUGVYTDd3aHhn?= =?utf-8?B?ZDZCTTA1QW5nM3J5LzJTa1I0Y0ZCTmhNY25qZ3dXb3F5azV1anIxOStOWVlE?= =?utf-8?B?NkZtdTN1Q05iaE9uelRXZDc4RWF3ZzVhWURGcEdjLzgwbDg2bUNJQ2xKdUNm?= =?utf-8?B?dlZzU2lhNTN3M0hwY1Z1bWg4eWVlWWJBWUcvU1NDS1lyaXh1dzZ4a2M4dzZD?= =?utf-8?B?a0IzZ29hUkcvWDBIamg2QUNxdGdRUzN3TUgyZ29PekduSVRHWjhqb1NvVDRr?= =?utf-8?B?a0JUcHJCeFdpZnY3bGtwVWdDZ0piWWRIMmJUYmRvZ0VZSUwxSHlnRVJlOW9i?= =?utf-8?B?Y2gzeDl5QVVnZHNVZ2hWUGF6N0pEejZEKzZnNGQwSTA2empZVXdNOEtnWHJR?= =?utf-8?B?TWFnOWxvWmNiUTFGcXVDZVowOFZUZUQ5bHFOcm5XRklQNVlDelNpQ1pHZ3hP?= =?utf-8?B?V3IzMkRrQUk3b2pocm9BQXFpdVRHbVpRdDYyN3JiYjdoMGxqQlBBSDVnYTRx?= =?utf-8?B?NUFxVklNeVRrTnJORi9GeTNGWUtHcXdFZmE3NkxlOVFoOWpDdjJPVEx5a1Qz?= =?utf-8?B?YjFMNDFjSXRXWi9uWXlURk9Cdy8reWhIT0IwdUFNR2dyUFRBVVdOMnBnYkho?= =?utf-8?B?NmVhOUxjMnMzbVRLZi9UNnlVeG9WYXVQTVhKQklUcTJCVkJaNEJpajRMYW1H?= =?utf-8?B?ZG54RWxseXF2ZlQreExidEVrSmtMdVdWN2llNU9BYXlhdlVwSGV3RC9YWFR3?= =?utf-8?B?N2N3dTU4eElGOUxXanRXdG1mSUx3QWNySGFiYjB5ZVNoTDNTNE4vblZ4UDZT?= =?utf-8?B?VnRhRDl5b1QyMmpyQ3FYR1VyL3F4UUVKclNNVHErc3VDaXowcHBOczFIaWtY?= =?utf-8?B?SW43cndtem4vazBrL2VLR1pGYVZ1UCtBWlJUUjIvWVBtQlVxYzZBeXRaZkVx?= =?utf-8?B?UkhOU3pZWU95SHpucmViVTJTU3lKemRvYVhrWjBkbmZMNUNFOEZuMlkyREFH?= =?utf-8?B?TWJ2MHVEeE5SL2xJN3Jjak0zajJkUVJjYW9kR090a0J5U1lsN3A0L0xUaGF0?= =?utf-8?B?dVFDc1F1U25wTllUMHUrY0oxNnNieGV5T01sSzRhWGlQdHlPcldOZHk0cVRX?= =?utf-8?B?dkNyd1ZnMmNWWGx1eFVveXBTNkpQbFFVdEo3cTM4bm4yUEVuZGovN0FOZU1X?= =?utf-8?B?WDBKdllVdnVoajh3Zkt4MkJJamVqQW90OC9Ja1JYQjhFZWp0eFRhb1d5QTZs?= =?utf-8?B?c3FtVHhEOG1PRDhaam5SVytPa3BBLzRuaUdXMDYxcUIzMW82NGpzbzRXR2FO?= =?utf-8?Q?Vei2NVIF0yo0KrUDs3hlRhSGtsg56Trg78r97Kt?= X-OriginatorOrg: virtuozzo.com X-MS-Exchange-CrossTenant-Network-Message-Id: 3142f506-952a-41f6-1b16-08d8fab36639 X-MS-Exchange-CrossTenant-AuthSource: AM7PR08MB5494.eurprd08.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 08 Apr 2021 17:26:09.5089 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 0bc7f26d-0264-416e-a6fc-8352af79c58f X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: Zgg++XFA567HAiiNmEJZxWfFJ8reZ55gSL8ISupLSsW9GynqHHtO+MWidpUHEifneL7G3oT0abKBgx2h9L2tMtZz2WQMxVTH//wVUgNHnHY= X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM5PR0801MB1651 Received-SPF: pass client-ip=40.107.15.138; envelope-from=vsementsov@virtuozzo.com; helo=EUR01-DB5-obe.outbound.protection.outlook.com X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, MSGID_FROM_MTA_HEADER=0.001, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" 08.04.2021 20:04, John Snow wrote: > On 4/8/21 12:58 PM, Vladimir Sementsov-Ogievskiy wrote: >> job-complete command is async. Can we instead just add a boolean like job->completion_requested, and set it if job-complete called in STANDBY state, and on job_resume job_complete will be called automatically if this boolean is true? > > job_complete has a synchronous setup, though -- we lose out on a lot of synchronous error checking in that circumstance. yes, that's a problem.. > > I was not able to audit it to determine that it'd be safe to attempt that setup during a drained section -- I imagine it won't work and will fail, though. > > So I thought we'd have to signal completion and run the setup *later*, but what do we do if we get an error then? Does the entire job fail? Do we emit some new event? ("BLOCK_JOB_COMPLETION_FAILED" ?) Is it recoverable? > Isn't it possible even now, that after successful job-complete job still fails and we report BLOCK_JOB_COMPLETED with error? And actually, how much benefit user get from the fact that job-complete may fail? We can make job-complete a simple always-success boolean flag setter like job-pause. And actual completion will be done in background, when possible. And if it fail, job just fails, like it does for any background io error. And user have to check error/success status of final BLOCK_JOB_COMPLETED anyway. -- Best regards, Vladimir