From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <dev-bounces@dpdk.org>
Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124])
	by inbox.dpdk.org (Postfix) with ESMTP id 13C53A0548;
	Fri,  3 Dec 2021 04:49:12 +0100 (CET)
Received: from [217.70.189.124] (localhost [127.0.0.1])
	by mails.dpdk.org (Postfix) with ESMTP id D12E04014F;
	Fri,  3 Dec 2021 04:49:10 +0100 (CET)
Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187])
 by mails.dpdk.org (Postfix) with ESMTP id 3BBFF40041
 for <dev@dpdk.org>; Fri,  3 Dec 2021 04:49:08 +0100 (CET)
Received: from dggpeml500024.china.huawei.com (unknown [172.30.72.53])
 by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4J4zMY2sLSzcZyQ;
 Fri,  3 Dec 2021 11:48:57 +0800 (CST)
Received: from [127.0.0.1] (10.67.100.224) by dggpeml500024.china.huawei.com
 (7.185.36.10) with Microsoft SMTP Server (version=TLS1_2,
 cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Fri, 3 Dec
 2021 11:49:05 +0800
Subject: Re: [RFC 0/1] integrate dmadev in vhost
To: Jiayu Hu <jiayu.hu@intel.com>, <dev@dpdk.org>
CC: <maxime.coquelin@redhat.com>, <i.maximets@ovn.org>,
 <chenbo.xia@intel.com>, <bruce.richardson@intel.com>,
 <harry.van.haaren@intel.com>, <john.mcnamara@intel.com>,
 <sunil.pai.g@intel.com>
References: <20211122105437.3534231-1-jiayu.hu@intel.com>
From: fengchengwen <fengchengwen@huawei.com>
Message-ID: <e3969d67-9e71-14e6-1593-35a0ed761300@huawei.com>
Date: Fri, 3 Dec 2021 11:49:05 +0800
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101
 Thunderbird/68.11.0
MIME-Version: 1.0
In-Reply-To: <20211122105437.3534231-1-jiayu.hu@intel.com>
Content-Type: text/plain; charset="utf-8"
Content-Language: en-US
Content-Transfer-Encoding: 7bit
X-Originating-IP: [10.67.100.224]
X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To
 dggpeml500024.china.huawei.com (7.185.36.10)
X-CFilter-Loop: Reflected
X-BeenThere: dev@dpdk.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: DPDK patches and discussions <dev.dpdk.org>
List-Unsubscribe: <https://mails.dpdk.org/options/dev>,
 <mailto:dev-request@dpdk.org?subject=unsubscribe>
List-Archive: <http://mails.dpdk.org/archives/dev/>
List-Post: <mailto:dev@dpdk.org>
List-Help: <mailto:dev-request@dpdk.org?subject=help>
List-Subscribe: <https://mails.dpdk.org/listinfo/dev>,
 <mailto:dev-request@dpdk.org?subject=subscribe>
Errors-To: dev-bounces@dpdk.org

Hi Jiayu

I notice that examples/vhost rely on VMDQ, Could the examples/vhost provide
options that do not depend on VMDQ?  In this way, many network adapters can
be used.

Thanks.


On 2021/11/22 18:54, Jiayu Hu wrote:
> Since dmadev is introduced in 21.11, to avoid the overhead of vhost DMA
> abstraction layer and simplify application logics, this patch integrates
> dmadev in vhost.
> 
> To enable the flexibility of using DMA devices in different function
> modules, not limited in vhost, vhost doesn't manage DMA devices.
> Applications, like OVS, need to manage and configure DMA devices and
> tell vhost what DMA device to use in every dataplane function call.
> 
> In addition, vhost supports M:N mapping between vrings and DMA virtual
> channels. Specifically, one vring can use multiple different DMA channels
> and one DMA channel can be shared by multiple vrings at the same time.
> The reason of enabling one vring to use multiple DMA channels is that
> it's possible that more than one dataplane threads enqueue packets to
> the same vring with their own DMA virtual channels. Besides, the number
> of DMA devices is limited. For the purpose of scaling, it's necessary to
> support sharing DMA channels among vrings.
> 

...