From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <przemyslaw.czesnowicz@intel.com>
Received: from mga03.intel.com (mga03.intel.com [134.134.136.65])
 by dpdk.org (Postfix) with ESMTP id E025D68BF
 for <dev@dpdk.org>; Thu, 18 Dec 2014 18:25:49 +0100 (CET)
Received: from orsmga001.jf.intel.com ([10.7.209.18])
 by orsmga103.jf.intel.com with ESMTP; 18 Dec 2014 09:18:19 -0800
X-ExtLoop1: 1
X-IronPort-AV: E=Sophos;i="5.07,601,1413270000"; d="scan'208";a="626095515"
Received: from irsmsx153.ger.corp.intel.com ([163.33.192.75])
 by orsmga001.jf.intel.com with ESMTP; 18 Dec 2014 09:20:39 -0800
Received: from irsmsx108.ger.corp.intel.com ([169.254.11.71]) by
 IRSMSX153.ger.corp.intel.com ([163.33.192.75]) with mapi id 14.03.0195.001;
 Thu, 18 Dec 2014 17:20:38 +0000
From: "Czesnowicz, Przemyslaw" <przemyslaw.czesnowicz@intel.com>
To: "Loftus, Ciara" <ciara.loftus@intel.com>, Thomas Monjalon
 <thomas.monjalon@6wind.com>
Thread-Topic: [dpdk-dev] [PATCH] vhost: add interface name to virtio-net struct
Thread-Index: AQHQGtLEcjdlFXE5jESNg2FD7ncNQpyVejoAgAAYGeCAAAHSEA==
Date: Thu, 18 Dec 2014 17:20:38 +0000
Message-ID: <FD920D91FA434C4988D04BF2D401125919D001B3@IRSMSX108.ger.corp.intel.com>
References: <1418914523-24530-1-git-send-email-ciara.loftus@intel.com>
 <2861628.6qtiPmT13X@xps13>
 <74F120C019F4A64C9B78E802F6AD4CC212578FCB@IRSMSX106.ger.corp.intel.com>
In-Reply-To: <74F120C019F4A64C9B78E802F6AD4CC212578FCB@IRSMSX106.ger.corp.intel.com>
Accept-Language: en-IE, en-US
Content-Language: en-US
X-MS-Has-Attach: 
X-MS-TNEF-Correlator: 
x-originating-ip: [163.33.239.180]
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
Cc: "dev@dpdk.org" <dev@dpdk.org>
Subject: Re: [dpdk-dev] [PATCH] vhost: add interface name to virtio-net
 struct
X-BeenThere: dev@dpdk.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: patches and discussions about DPDK <dev.dpdk.org>
List-Unsubscribe: <http://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: <http://dpdk.org/ml/listinfo/dev>,
 <mailto:dev-request@dpdk.org?subject=subscribe>
X-List-Received-Date: Thu, 18 Dec 2014 17:25:50 -0000


> Hi Thomas,
>=20
> A basic vHost use case will work, for example a single Virtual Machine wi=
th a
> vHost port. However normal vSwitching use cases will require the use of m=
ultiple
> vHost ports and multiple VMs. With that in mind, it is essential that the=
 vSwitch
> has some way of knowing which vHost port it is sending to and receiving p=
ackets
> from. This patch resolves this issue by exposing the tap device name of t=
he
> vHost device. Without that information we cannot determine the particular
> vHost port to send/receive from, which in the context of switching, is a =
critical
> problem.


Exactly.
The vSwitch uses tap name to associate the virtio device with ovs port.
Without this change the vhost library cannot be used in vSwitch.

Regards
Przemek

>=20
> Thanks,
> Ciara
>=20