From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <Jerin.JacobKollanukkaran@cavium.com>
Received: from NAM02-SN1-obe.outbound.protection.outlook.com
 (mail-sn1nam02on0066.outbound.protection.outlook.com [104.47.36.66])
 by dpdk.org (Postfix) with ESMTP id 58E91727A
 for <dev@dpdk.org>; Tue, 23 Jan 2018 05:36:10 +0100 (CET)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
 d=CAVIUMNETWORKS.onmicrosoft.com; s=selector1-cavium-com;
 h=From:Date:Subject:Message-ID:Content-Type:MIME-Version;
 bh=/OEa4rNnjs8t/FZFd9LaYGSDOIexW+zwc2dhJP7w+dg=;
 b=h+495B8eWxkCOCOaY6ceHUT22CriqKNyEhsRiL5g1Ix/JqqDWS81Neb9KKkUbUNsSopZwcUMvMdT2CQAwDi0e65d0QkBCtPvV3XB+EwG/opedvkmbrb9l/mMl4QhETB0diIX8M171/ekE2Xo1yX1QAIeuhJSXnDYb5DJmnJBlHk=
Authentication-Results: spf=none (sender IP is )
 smtp.mailfrom=Jerin.JacobKollanukkaran@cavium.com; 
Received: from jerin (111.93.218.67) by
 CY1PR07MB2522.namprd07.prod.outlook.com (10.167.16.13) with Microsoft SMTP
 Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384_P256) id
 15.20.428.17; Tue, 23 Jan 2018 04:36:04 +0000
Date: Tue, 23 Jan 2018 10:05:28 +0530
From: Jerin Jacob <jerin.jacob@caviumnetworks.com>
To: Yongseok Koh <yskoh@mellanox.com>
Cc: Andrew Rybchenko <arybchenko@solarflare.com>,
 Thomas Monjalon <thomas@monjalon.net>,
 "jianbo.liu@arm.com" <jianbo.liu@arm.com>,
 Adrien Mazarguil <adrien.mazarguil@6wind.com>,
 =?iso-8859-1?Q?N=E9lio?= Laranjeiro <nelio.laranjeiro@6wind.com>,
 "bruce.richardson@intel.com" <bruce.richardson@intel.com>,
 "Ananyev, Konstantin" <konstantin.ananyev@intel.com>,
 Chao Zhu <chaozhu@linux.vnet.ibm.com>, "dev@dpdk.org" <dev@dpdk.org>
Message-ID: <20180123043527.GA2957@jerin>
References: <20180116011050.18866-1-yskoh@mellanox.com>
 <20180119004430.15305-1-yskoh@mellanox.com>
 <20180119004430.15305-2-yskoh@mellanox.com>
 <805e1578-6e4d-6a1b-00ce-13e3b1c16be8@solarflare.com>
 <5B266F6C-A33B-4019-BFDE-9CAC80835200@mellanox.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=iso-8859-1
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <5B266F6C-A33B-4019-BFDE-9CAC80835200@mellanox.com>
User-Agent: Mutt/1.9.2 (2017-12-15)
X-Originating-IP: [111.93.218.67]
X-ClientProxiedBy: BM1PR01CA0089.INDPRD01.PROD.OUTLOOK.COM (10.174.208.157) To
 CY1PR07MB2522.namprd07.prod.outlook.com (10.167.16.13)
X-MS-PublicTrafficType: Email
X-MS-Office365-Filtering-Correlation-Id: 6d5bc000-e5e8-45b8-e47e-08d5621ad28b
X-Microsoft-Antispam: UriScan:; BCL:0; PCL:0;
 RULEID:(7020095)(4652020)(4534145)(4627221)(201703031133081)(201702281549075)(5600026)(4604075)(2017052603307)(7153060)(7193020);
 SRVR:CY1PR07MB2522; 
X-Microsoft-Exchange-Diagnostics: 1; CY1PR07MB2522;
 3:HXIPwEqIs9D8f3JOFRXVHFuOvioR4BO1INCEQDVQigjPyyNgEMgHlaPtdpXpxjgZof0odqZRaA7SukIbrCpd/FX6oOu4mmz4Zi/Dzb5JMqFJ2e03YxZj/hTP01UjODKurNqRkgMWQDDmspAQi2m5pTwRJmlemeuDXwk/dPr38b8F7fye9jujtibwhYRM/lwjB+FozgFz+zxHQ6UCd816Xjbwfe89Gkj3h4cOwNOuengtIS4rJLC8zgRq7YQXWEvA;
 25:MB+0itYnyMEV519Q82iVCbtFeuhAZAQDCuv8LczhzuCu0AxtmZVdO/gsJabj7JCH3s6lcerTHtMyhZ0enYMxABgifXqnTQnvT650CDLflU+LdqzYShgRyX5BVB8WUA8XN9ywNdZ7xdEXIfAQZj9tsMB7zqJ9fL0G3ns3/jZEBI6KThLC9RY9Zu0C5jdljqHObDkcphRYRDVUS4ndeqOCBREtxd/OZ8kv1HiQX0hnX57CkcOvIhUEBcC07Hk6va5h2fUBez52emyQTvopgDK1rELCI3QBX54R0EBxl4KKhFtwTgHfPL8dj+lBRZDCvLJlSQQpv2BqmkLKSXg20EMz3A==;
 31:RvcJc0mWKKoS7BojjYJ8cFvUudYvoXZe62VjZq5dW7nrhmqcQ5MmcqVwtO5EbQJ98a+N7YKQGu3eCjEQm2nxz8j9LasBmYVWfjqGHx6q/s7z/1BxOxyKqNokaLk7wLIdeG1N8sGCZEkzdxqBiXlhRj6TPQ4QQG2l9V5NpjeZa0CCUUQGyfm94SZ/r9kr/DuXk1j5Kso1witlzB9LH3QumhcQIjowjiV2zyBjzbx4Tec=
X-MS-TrafficTypeDiagnostic: CY1PR07MB2522:
X-Microsoft-Exchange-Diagnostics: 1; CY1PR07MB2522;
 20: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
X-Microsoft-Antispam-PRVS: <CY1PR07MB2522B2F8635F58062935B0C1E3E30@CY1PR07MB2522.namprd07.prod.outlook.com>
X-Exchange-Antispam-Report-Test: UriScan:(180628864354917)(104084551191319)(228905959029699); 
X-Exchange-Antispam-Report-CFA-Test: BCL:0; PCL:0;
 RULEID:(6040501)(2401047)(8121501046)(5005006)(3002001)(3231023)(2400081)(944501161)(10201501046)(93006095)(6041288)(20161123560045)(20161123562045)(201703131423095)(201702281528075)(20161123555045)(201703061421075)(201703061406153)(20161123558120)(20161123564045)(6072148)(201708071742011);
 SRVR:CY1PR07MB2522; BCL:0; PCL:0; RULEID:(100000803101)(100110400095);
 SRVR:CY1PR07MB2522; 
X-Microsoft-Exchange-Diagnostics: 1; CY1PR07MB2522;
 4:a0dlZrVZeF7uCffRtLnhJcXwA1tT/W8hOqNhx2ZJzI1k39//3rwK1kRI1k08tQ5qHRm3ZkHSBwYVD5j8bG0KRdJRzIyeUdzeKGnuH5tbFLYFKriw6qPPbj3FZNXzcLKqur82DTYU4gCNptJjKrvWEcLaPk9KrvAjAIiwB9siEJ/YZQ5K4lgzvXWpNcVYWK6nFb9dNmn0ML9JQxb2GQDp1C1j57hpu074/9m8fSz6gCg5DipZQmFNrbx7nN842DTyVtZI+jhYjsCUeJEP4U3xQhypq6qnF88k4QYP+e5FIYf8GiIme0QV1Uk9ucRXFknfaO8lVEqsaED1S8saHxZCUd+KQcNLCZwzXj0Ndl5bd+q0ywY+5HjYpMGGP+e73aUt
X-Forefront-PRVS: 05610E64EE
X-Forefront-Antispam-Report: SFV:NSPM;
 SFS:(10009020)(39850400004)(346002)(396003)(376002)(366004)(39380400002)(189003)(199004)(13464003)(2950100002)(54906003)(9686003)(33716001)(66066001)(33656002)(47776003)(81166006)(316002)(97736004)(7736002)(305945005)(55016002)(53936002)(2906002)(8676002)(7416002)(8936002)(106356001)(81156014)(52116002)(105586002)(6116002)(3846002)(6246003)(26005)(5660300001)(42882006)(16526018)(23756003)(58126008)(68736007)(386003)(478600001)(5009440100003)(6496006)(59450400001)(72206003)(25786009)(93886005)(83506002)(1076002)(50466002)(6666003)(53546011)(76176011)(4326008)(229853002)(6916009)(2870700001)(33896004)(18370500001);
 DIR:OUT; SFP:1101; SCL:1; SRVR:CY1PR07MB2522; H:jerin; FPR:; SPF:None;
 PTR:InfoNoRecords; MX:1; A:1; LANG:en; 
Received-SPF: None (protection.outlook.com: cavium.com does not designate
 permitted sender hosts)
X-Microsoft-Exchange-Diagnostics: =?iso-8859-1?Q?1; CY1PR07MB2522;
 23:1Wtp1v9UqzMKwKeEo1KvC2w7CN+OZwvVVAvEb+i?=
 =?iso-8859-1?Q?v2mDfb2EWlz2vuXMALTcGcD+iOehmefjImSz3SMeu+h9FsdyqtzsgehcSm?=
 =?iso-8859-1?Q?0BC9zE0kicUXnGgHjZzNFtbJlPwcDY++QRpOuR56aWEezjjwUELrVU8MSL?=
 =?iso-8859-1?Q?8ssSkTwknIKhXFlCmfL1EQC0vDI5Fcn3M5Ux624U6lku0sKhfuJqjV4mfw?=
 =?iso-8859-1?Q?rdg6NNOh6MeurkN/y74wk76p0dfr/zkhLbrwYUDXDNX87Cdh9g1bv3lIbY?=
 =?iso-8859-1?Q?wWUcvxEh85zaIeglgrScSKV4tRHTDaBcTcZ5oEHnN+BG3D6Hk6BcE5m6VT?=
 =?iso-8859-1?Q?XsBnFMzBOCszDRx9uqaKYQE1JT1Gy5zFFDippmB/7K2Y2Ku55eBsGHQfy4?=
 =?iso-8859-1?Q?kRboF4rjmTzlXTb5/O0Xw6x0Ovcd6Y5cGDYSHQ49+A/Uqs+zUiYEROnJq0?=
 =?iso-8859-1?Q?8Tk6lKdMqDgIJ6EoQzPt4bV9UBCyzbA1Jts4c/BZH8Zz7vvSh36TF/AG8Z?=
 =?iso-8859-1?Q?Ky4xNZwd+sPDF0lDxaSJ6Z6rNp2FajdrCDW16nM7A3eS0hfMS12VUzEKC/?=
 =?iso-8859-1?Q?fP0kBGp6JpRHKOPG/gPy2klq+RS+7WwLjmgnxYkF+VIy4iDBWkZw4mflnA?=
 =?iso-8859-1?Q?tyhnAImDvMM0VCNp9ZcvA47RTjbU7ghnkLR/m27wvD+3w/ACJ+aZh8+44D?=
 =?iso-8859-1?Q?rs6pfAWQxX/TdP6gWLl/9S2y+fWM+iKWNhTcXqWbEqdY4/rzf+6tnnZl1f?=
 =?iso-8859-1?Q?WMG/N9fzu2pXmzs4mvFj8CHSYxKfjUYF5/CnWfjK9q9aMSIjknTXv6bW5q?=
 =?iso-8859-1?Q?ZWjptlCf2wrLaxuyNdMKS8BjjdYS2KWeNT/JHO/x8NKuM2Xn4yYOU2vybT?=
 =?iso-8859-1?Q?J9SoS2THaH78jiAc21x1mUIqoVoisrXgWWgc9I6U74CQtbuYPZAvwq/nIt?=
 =?iso-8859-1?Q?qEBfPg4pZW3ruZKuQ2dpaZ0OhI0StittvITNqWxQSkDThRFQWIHq5Z0Mpa?=
 =?iso-8859-1?Q?1PsXvtR94wotNswT7rw0ThnWbd2zGGCAfxRbfiKR/Y7i0FlevCBcMS8i86?=
 =?iso-8859-1?Q?m9WebGR0A5qg8TFNShZTq7VmbpF3sxt/DSs60ADcXltD4tpIqCa0XOLi1b?=
 =?iso-8859-1?Q?c6nXl5tI8chuyE0AMfJdgwzNz1Xqxc92wQjZUlVgrQPfACmsy8BI7XXmeo?=
 =?iso-8859-1?Q?fC0y9HgNQhvfG6tsT/zSHF4wxDU8a3MiSLUEqKrA0/q2vRyg/+lvzYYAhi?=
 =?iso-8859-1?Q?yOlxh4jdRa3xWiQaR/sVr2jTabXvJzX9npZmDESEqDIJiXnjHyp6+XIkJs?=
 =?iso-8859-1?Q?Nyj+XD1CJaQPKd1hbsjd7CzRbsHgJAJzDVYJm7mIMONUcqWnGgUMxyjUnp?=
 =?iso-8859-1?Q?M1T8wpDaU2k59qJxXqFkJ1Klc8Gsx4ZWK0G25BAA4WNzA7E6tXwlS5zjA3?=
 =?iso-8859-1?Q?Y4dxMjxwl8W2fiJdr2zalSlKiWVocKwlQ5t?=
X-Microsoft-Exchange-Diagnostics: 1; CY1PR07MB2522;
 6:gX3t8Q6b7/mMECxMRS8J218/FP57ANdRf28ql/F7N7uQXGBrg3Y97YgD3apg2I63G53FQEGGOxVTCWcjzsXMAXqcw+rph5NBv/slKVVIIdav1o7ppRQJp8ixgKn+r75StUpauKobOiDjSegrZZPx3u92CtOfuLR8Gpa4DyiuRpE0P0RErtKocDEt4LdrnbJVivL3JAHQmOa18f2UyeBBjSx/A3hkRwlt1nrP54F50IBYQEL0AkLPdN+KUHDrVcwCHKzwfA8Skk/slQIav56gMj2AB399/I4UhK8+2tsP4daHdC+u6CFKvwsQJzb+Gc7ZJqryEHELjykclUx6R5epE906/VjNPcvHypZO61K4Sio=;
 5:R5dptG+P1tsVOmzCu37K7WMCwkGTZyl6zrmcDiZRRI/pAe0jGdIW+PpBlAzQM1j73Wquyp+cvYa+wb6gpM6hD4jgijTPEnLkPqRSuN1KvX2BDGhV3QaWqiigp4R27Qdq2OEPJ5VkmZLdTMR4MMKiWMCQcQME2eaeBpA/v9B772I=;
 24:wq+3UzgluADvdga/0gaZqyNJbkyRL4mV9nMKN0kS5qAhJ7xPwOOxrURXxQ3oE0IdGEiKA/887/x+q5zr5qGD8n2FzFlrg2/7XeKSo3yhBvM=;
 7:nYvWoGwvPxaBypVz8q7ByCDo3eApCc0h8Ccs+kO3aWWzulMBinEqmjVD4EXTnVFpoFEkUaClFmn1w6wg8Gh77OUxjEUg779h/QW2chL5uKY4qVtAYHvuiVUi8Q8KUZGIXqIDJxvrS6MsbiE41SYtQ28rQZGCWwbR6EdiQy6B1S7G0d86W5lIoddJ7BcvHVe3M67WqcmApHwISpsT0h/yDM8ONGoUQIyHf5qRfS31IB/UDIJyENHEUtXr+stj8G7Z
SpamDiagnosticOutput: 1:99
SpamDiagnosticMetadata: NSPM
X-OriginatorOrg: caviumnetworks.com
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 23 Jan 2018 04:36:04.8223 (UTC)
X-MS-Exchange-CrossTenant-Network-Message-Id: 6d5bc000-e5e8-45b8-e47e-08d5621ad28b
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 711e4ccf-2e9b-4bcf-a551-4094005b6194
X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY1PR07MB2522
Subject: Re: [dpdk-dev] [PATCH v3 1/8] eal: introduce DMA memory barriers
X-BeenThere: dev@dpdk.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: DPDK patches and discussions <dev.dpdk.org>
List-Unsubscribe: <https://dpdk.org/ml/options/dev>,
 <mailto:dev-request@dpdk.org?subject=unsubscribe>
List-Archive: <http://dpdk.org/ml/archives/dev/>
List-Post: <mailto:dev@dpdk.org>
List-Help: <mailto:dev-request@dpdk.org?subject=help>
List-Subscribe: <https://dpdk.org/ml/listinfo/dev>,
 <mailto:dev-request@dpdk.org?subject=subscribe>
X-List-Received-Date: Tue, 23 Jan 2018 04:36:10 -0000

-----Original Message-----
> Date: Mon, 22 Jan 2018 18:29:31 +0000
> From: Yongseok Koh <yskoh@mellanox.com>
> To: Andrew Rybchenko <arybchenko@solarflare.com>, Thomas Monjalon
>  <thomas@monjalon.net>, "jianbo.liu@arm.com" <jianbo.liu@arm.com>, Jerin
>  Jacob <jerin.jacob@caviumnetworks.com>
> CC: Adrien Mazarguil <adrien.mazarguil@6wind.com>, Nélio Laranjeiro
>  <nelio.laranjeiro@6wind.com>, "bruce.richardson@intel.com"
>  <bruce.richardson@intel.com>, "Ananyev, Konstantin"
>  <konstantin.ananyev@intel.com>, Chao Zhu <chaozhu@linux.vnet.ibm.com>,
>  "dev@dpdk.org" <dev@dpdk.org>
> Subject: Re: [dpdk-dev] [PATCH v3 1/8] eal: introduce DMA memory barriers
> 
> 
> > On Jan 18, 2018, at 11:16 PM, Andrew Rybchenko <arybchenko@solarflare.com> wrote:
> > 
> > On 01/19/2018 03:44 AM, Yongseok Koh wrote:
> >> This commit introduces rte_dma_wmb() and rte_dma_rmb(), in order to
> >> guarantee the ordering of coherent shared memory between the CPU and a DMA
> >> capable device.
> >> 
> >> Signed-off-by: Yongseok Koh 
> >> <yskoh@mellanox.com>
> > 
> > Acked-by: Andrew Rybchenko <arybchenko@solarflare.com>
> > 
> > It is already really good. Many thanks.
> 
> Thank you!
> 
> > Maybe it would be useful to:
> >  - avoid duplication of so long explanations (put in in one place and add reference?)
> 
> May have to ask Thomas how to do this. Thomas?
> 
> >  - explain why it is bound to DMA or call it in a different way, since right now it is bound
> >    to coherent-mapped IO (rte_cio_rmb() ?). Yes, I see benefits to follow Linux
> >    terminology, but may be DPDK can do better :) I just add my concerns, but let
> >    EAL code maintainers to decide
> 
> Good idea. Like to hear from other people. But, following linux terms sometime
> could be good to welcome developers from kernel community to DPDK world. :-)
> 
> To people in the cc list, any other concerns?
> Especially ARM users - Jianbo and Jerin?

I like Andrew's suggestion. IMO, rte_cio_?mb() makes more sense.

> 
> Thanks,
> Yongseok