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=-21.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 45274C433EF for ; Sun, 5 Sep 2021 22:21:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 16E4460BD3 for ; Sun, 5 Sep 2021 22:21:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236681AbhIEWWW (ORCPT ); Sun, 5 Sep 2021 18:22:22 -0400 Received: from mail-bn8nam11on2080.outbound.protection.outlook.com ([40.107.236.80]:61297 "EHLO NAM11-BN8-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S232617AbhIEWWV (ORCPT ); Sun, 5 Sep 2021 18:22:21 -0400 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=kwIJoWMnmiJC92jDdH9N3cMMqEVLxdO9+6QnRUUQf2Rs4B0LXNIpZMWoYHYTUUAlEjvZta+NDnkAH1VtpMYCtrory14ftO+JK8fVgx4E06/vzcRsXumZD8hSbNnx57RUlyYKsl2CdW/WXyGRiSH2u4Ojm+KUG8UrHa5OZdB8hTkKry1IoM+ZHch7o1+3IMy3ZSvYeuM7uykRNRAwqukdUjBIqCWEJ888QYfzvW9u34eOgFnA4XOAw7ZaOEp+g5BdLUCSZD4rPActtyyvDHo5rH7d3Wdd8FIR3jgXO0Oj98yl6jkGoVblMf1eNh6tkj7NHm5PyBWraph7ogVuS9Z4zw== 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; bh=jWGdwH6ht//CC0tk8nyEqsG+qD6gMGYuZA5xWVv4VFo=; b=EgQMI/Sc3YyRajDZs0aUa5fQlyKFFUUO88IzgVLUz/EwRY+ae/xeZ+r9CahkmiwDhbvddpyjIzDI5UYxDd1zc/Pon/7xmggdZYKMdkjA2rLQEyB8+xJ9jc+YYzAbk2Q/JpuGCshSF61XVPDW6KXXbKnOLLaL8VWVymRuZiAR7vGz0kJnF9UIgHQeXyZG7rZo3ND10tpKcBjrhhoppO0Iuh0IZbGQeM2b/8Vc5dTEGdTxYx8xAs3OUeGcc3RX8dvN97etHVj2CKOvg4v9bjtGyZls7vX63ARZRrEa2C/9RUhZ0RXm8FLKBFqR1hxMm9Fn/06VCUY88y0MjbARlBmdHw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass (sender ip is 216.228.112.34) smtp.rcpttodomain=lists.linux-foundation.org smtp.mailfrom=nvidia.com; dmarc=pass (p=quarantine sp=none pct=100) action=none header.from=nvidia.com; dkim=none (message not signed); arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Nvidia.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=jWGdwH6ht//CC0tk8nyEqsG+qD6gMGYuZA5xWVv4VFo=; b=HBc6HBYWJhsjFd6Oss9Z3d7D8vmTs2/QXHIVWYThgNfr6TFpG61S2aD37AmjoRAUikkPZ0Fh5OQs+4bGtlzQQsN6jKrGiNVD6iJP4KfCgtI/A49kbIx+bt71IdRSkx24W3j5OCdGm7ppy0gQM2WXb6tZHrMdTmDNMuPZQO/tirQyrw+J+DRcV4jzD2EPCyUiIRqmXEcRhaRl2DZghYB4jvW9L7xc55vBVziAE+71+s6dWMin9Y4jXeYChAN/SmUJl44zwFuRPMk/gZ7gHXThFu4ulKreEpC1R3zEngbL3OCxmAIpDJ8WieC7yQaAgH/aiekcArxDtTts1jFr/FvOSw== Received: from DM6PR01CA0021.prod.exchangelabs.com (2603:10b6:5:296::26) by DM6PR12MB2844.namprd12.prod.outlook.com (2603:10b6:5:45::32) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4478.21; Sun, 5 Sep 2021 22:21:15 +0000 Received: from DM6NAM11FT042.eop-nam11.prod.protection.outlook.com (2603:10b6:5:296:cafe::ea) by DM6PR01CA0021.outlook.office365.com (2603:10b6:5:296::26) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4478.20 via Frontend Transport; Sun, 5 Sep 2021 22:21:15 +0000 X-MS-Exchange-Authentication-Results: spf=pass (sender IP is 216.228.112.34) smtp.mailfrom=nvidia.com; lists.linux-foundation.org; dkim=none (message not signed) header.d=none;lists.linux-foundation.org; dmarc=pass action=none header.from=nvidia.com; Received-SPF: Pass (protection.outlook.com: domain of nvidia.com designates 216.228.112.34 as permitted sender) receiver=protection.outlook.com; client-ip=216.228.112.34; helo=mail.nvidia.com; Received: from mail.nvidia.com (216.228.112.34) by DM6NAM11FT042.mail.protection.outlook.com (10.13.173.165) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.20.4478.19 via Frontend Transport; Sun, 5 Sep 2021 22:21:14 +0000 Received: from [172.27.0.7] (172.20.187.6) by HQMAIL107.nvidia.com (172.20.187.13) with Microsoft SMTP Server (TLS) id 15.0.1497.18; Sun, 5 Sep 2021 22:21:12 +0000 Subject: Re: [PATCH 1/1] virtio: add VIRTIO_F_IN_ORDER to header file To: "Michael S. Tsirkin" CC: , , , , References: <20210905120911.8239-1-mgurtovoy@nvidia.com> <20210905110804-mutt-send-email-mst@kernel.org> From: Max Gurtovoy Message-ID: Date: Mon, 6 Sep 2021 01:21:09 +0300 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.13.0 MIME-Version: 1.0 In-Reply-To: <20210905110804-mutt-send-email-mst@kernel.org> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-Originating-IP: [172.20.187.6] X-ClientProxiedBy: HQMAIL111.nvidia.com (172.20.187.18) To HQMAIL107.nvidia.com (172.20.187.13) X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 3ff48c21-6064-4c29-8b86-08d970bb7987 X-MS-TrafficTypeDiagnostic: DM6PR12MB2844: X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:8273; X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: xJKlSqwcNrtQPajnLY8i7HeG1LImqs5tZN07Wytnv0KZzQXyi1g+biObS1pIpbsj2kfigkWXBneBrL6ESGR6yUKENaMBIVU9n1oTytOW/NSa2JDKefttmHAu05i9Dg3ssTaLtYYItjedQGpMWj7w61XexpHGX1LV0pkqMiASELttRhJLwmxyEZPADQopvrnWb0+fRMuk+CjhQAUHCA1gjJlAs4M00mtTh1FKLh3pEDmdh2do6yKqC7fy/jveeRvKEQR6qf9IVndYBZs8QYOGUYwjjol8g+O2cQZNrANIhwi4GIsfSZWY+siUtC8HXTJXweU4XnYiBhAWe/EKN5rcRBopr6Gf2cP2L8OeKMiROxgXHVT7OoXk/TkZB1gzdMpUcNWYiMilgN5MUFHMJPFh147L2dGQA6P6sD2FJuKIspNGkU72rpaPz9tiIeWUwRYiGsn/Ku7jVj5Gtb7NQjefMgxB8JsT64gApP/iO7+RzgeTzrB8PZlxIj1cS+LkH3MCSf1wnSFzIaFz0Tq6QorNSgt+F2XtLSCS4cwVCnRtT3POhm8RfZRsG4uy3WRs7VXLfseLPnIOuV8yIhULfcODgoiQDxHa2jyhxzP6oVpn27pIW8XaP02rI2xplBwm5JJ314N15Y1yScgUV27pV+rWXDXVYMZQUneHgFSf1jD8/bBvxaxzR+68kguFeUx6Yekx38lV9q7qZp6H32QsmrUDl3mkzJZS9cNKwMR6wSkKjZI= X-Forefront-Antispam-Report: CIP:216.228.112.34;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:mail.nvidia.com;PTR:schybrid03.nvidia.com;CAT:NONE;SFS:(4636009)(376002)(39860400002)(396003)(346002)(136003)(46966006)(36840700001)(53546011)(54906003)(2616005)(36860700001)(83380400001)(6916009)(336012)(426003)(356005)(8936002)(16526019)(186003)(7636003)(8676002)(26005)(36906005)(107886003)(5660300002)(2906002)(31686004)(4326008)(31696002)(36756003)(316002)(16576012)(82740400003)(86362001)(6666004)(47076005)(478600001)(82310400003)(70586007)(70206006)(43740500002);DIR:OUT;SFP:1101; X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 05 Sep 2021 22:21:14.8687 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 3ff48c21-6064-4c29-8b86-08d970bb7987 X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[216.228.112.34];Helo=[mail.nvidia.com] X-MS-Exchange-CrossTenant-AuthSource: DM6NAM11FT042.eop-nam11.prod.protection.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR12MB2844 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On 9/5/2021 6:09 PM, Michael S. Tsirkin wrote: > On Sun, Sep 05, 2021 at 03:09:11PM +0300, Max Gurtovoy wrote: >> For now only add this definition from the spec. In the future, The >> drivers should negotiate this feature to optimize the performance. >> >> Signed-off-by: Max Gurtovoy > So I think IN_ORDER was a mistake since it breaks ability > to do pagefaults efficiently without stopping the ring. I'm not sure I get it. I wanted to use it for improving performance of a virtio-blk device by coalescing many completions to one interrupt. > I think that VIRTIO_F_PARTIAL_ORDER is a better option - > am working on finalizing that proposal, will post RSN now. > > >> --- >> include/uapi/linux/virtio_config.h | 6 ++++++ >> 1 file changed, 6 insertions(+) >> >> diff --git a/include/uapi/linux/virtio_config.h b/include/uapi/linux/virtio_config.h >> index b5eda06f0d57..3fcdc4ab6f19 100644 >> --- a/include/uapi/linux/virtio_config.h >> +++ b/include/uapi/linux/virtio_config.h >> @@ -82,6 +82,12 @@ >> /* This feature indicates support for the packed virtqueue layout. */ >> #define VIRTIO_F_RING_PACKED 34 >> >> +/* >> + * This feature indicates that all buffers are used by the device in the same >> + * order in which they have been made available. >> + */ >> +#define VIRTIO_F_IN_ORDER 35 >> + >> /* >> * This feature indicates that memory accesses by the driver and the >> * device are ordered in a way described by the platform. >> -- >> 2.18.1