From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <jing.d.chen@intel.com>
Received: from mga04.intel.com (mga04.intel.com [192.55.52.120])
 by dpdk.org (Postfix) with ESMTP id 4714B295B
 for <dev@dpdk.org>; Thu, 25 Feb 2016 11:04:07 +0100 (CET)
Received: from orsmga001.jf.intel.com ([10.7.209.18])
 by fmsmga104.fm.intel.com with ESMTP; 25 Feb 2016 02:04:07 -0800
X-ExtLoop1: 1
X-IronPort-AV: E=Sophos;i="5.22,497,1449561600"; d="scan'208";a="894383451"
Received: from fmsmsx107.amr.corp.intel.com ([10.18.124.205])
 by orsmga001.jf.intel.com with ESMTP; 25 Feb 2016 02:04:06 -0800
Received: from fmsmsx114.amr.corp.intel.com (10.18.116.8) by
 fmsmsx107.amr.corp.intel.com (10.18.124.205) with Microsoft SMTP Server (TLS)
 id 14.3.248.2; Thu, 25 Feb 2016 02:04:05 -0800
Received: from shsmsx104.ccr.corp.intel.com (10.239.4.70) by
 FMSMSX114.amr.corp.intel.com (10.18.116.8) with Microsoft SMTP Server (TLS)
 id 14.3.248.2; Thu, 25 Feb 2016 02:04:05 -0800
Received: from shsmsx102.ccr.corp.intel.com ([169.254.2.232]) by
 SHSMSX104.ccr.corp.intel.com ([169.254.5.132]) with mapi id 14.03.0248.002;
 Thu, 25 Feb 2016 18:04:03 +0800
From: "Chen, Jing D" <jing.d.chen@intel.com>
To: Thomas Monjalon <thomas.monjalon@6wind.com>, "Richardson, Bruce"
 <bruce.richardson@intel.com>, "Wang, Xiao W" <xiao.w.wang@intel.com>
Thread-Topic: [dpdk-dev] [PATCH v3 1/3] fm10k: enable FTAG based forwarding
Thread-Index: AQHRXv2b9vHgG11UkkGrqGmAhlBTXp867/aAgAAPUoCAAaZ94A==
Date: Thu, 25 Feb 2016 10:04:02 +0000
Message-ID: <4341B239C0EFF9468EE453F9E9F4604D04450107@shsmsx102.ccr.corp.intel.com>
References: <1454410216-13333-2-git-send-email-xiao.w.wang@intel.com>
 <1454557129-12825-2-git-send-email-xiao.w.wang@intel.com>
 <20160224154255.GA21808@bricha3-MOBL3> <13026611.uCVrZtfrBT@xps13>
In-Reply-To: <13026611.uCVrZtfrBT@xps13>
Accept-Language: en-US
Content-Language: en-US
X-MS-Has-Attach: 
X-MS-TNEF-Correlator: 
x-originating-ip: [10.239.127.40]
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 v3 1/3] fm10k: enable FTAG based forwarding
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, 25 Feb 2016 10:04:07 -0000

Hi, Bruce, Thomas,

Best Regards,
Mark

> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Thomas Monjalon
> Sent: Thursday, February 25, 2016 12:38 AM
> To: Richardson, Bruce; Wang, Xiao W
> Cc: dev@dpdk.org
> Subject: Re: [dpdk-dev] [PATCH v3 1/3] fm10k: enable FTAG based
> forwarding
>=20
> 2016-02-24 15:42, Bruce Richardson:
> > On Thu, Feb 04, 2016 at 11:38:47AM +0800, Wang Xiao W wrote:
> > > This patch enables reading sglort info into mbuf for RX and inserting
> > > an FTAG at the beginning of the packet for TX. The vlan_tci_outer fie=
ld
> > > selected from rte_mbuf structure for sglort is not used in fm10k now.
> > > In FTAG based forwarding mode, the switch will forward packets
> according
> > > to glort info in FTAG rather than mac and vlan table.
> > >
> > > To activate this feature, user needs to turn
> ``CONFIG_RTE_LIBRTE_FM10K_FTAG_FWD``
> > > to y in common_linuxapp or common_bsdapp. Currently this feature is
> supported
> > > only on PF, because FM10K_PFVTCTL register is read-only for VF.
> > >
> > > Signed-off-by: Wang Xiao W <xiao.w.wang@intel.com>
> >
> > Any comments on this patch?
> >
> > My thoughts: is there a way in which this could be done without adding =
in a
> new
> > build time config option?
>=20
> Bruce, it's simpler to explain that build time options are forbidden to
> enable such options.
> Or the terrific kid's approach: one day, the Big Build-Option Eater will =
come
> and will eat every undecided features! ;)

This feature is trying to use FTAG (a unique tech in fm10k) instead of mac/=
vlan
to forward packets. App need a way to tell PMD driver that which forwarding
style it would like to use.=20
So, the best option is to let packets carry a flag in mbuf to tell drive in=
 fast path.=20
You can see that this is unique to fm10k and we thought community won't lik=
e to see=20
this flag introduced into mbuf. If you do agree, we can introduce a new fla=
g.
So, we step backwards and assume customer will use static configurations to=
 enable
this feature. After it is enabled, we'll assume app will use FTAG for all p=
ackets.