From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: <xiao.w.wang@intel.com> Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by dpdk.org (Postfix) with ESMTP id ADE612C64 for <dev@dpdk.org>; Fri, 26 Feb 2016 10:24:10 +0100 (CET) Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga102.jf.intel.com with ESMTP; 26 Feb 2016 01:24:09 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.22,498,1449561600"; d="scan'208";a="659631438" Received: from fmsmsx108.amr.corp.intel.com ([10.18.124.206]) by FMSMGA003.fm.intel.com with ESMTP; 26 Feb 2016 01:24:09 -0800 Received: from fmsmsx113.amr.corp.intel.com (10.18.116.7) by FMSMSX108.amr.corp.intel.com (10.18.124.206) with Microsoft SMTP Server (TLS) id 14.3.248.2; Fri, 26 Feb 2016 01:24:08 -0800 Received: from shsmsx151.ccr.corp.intel.com (10.239.6.50) by FMSMSX113.amr.corp.intel.com (10.18.116.7) with Microsoft SMTP Server (TLS) id 14.3.248.2; Fri, 26 Feb 2016 01:24:08 -0800 Received: from shsmsx101.ccr.corp.intel.com ([169.254.1.136]) by SHSMSX151.ccr.corp.intel.com ([169.254.3.18]) with mapi id 14.03.0248.002; Fri, 26 Feb 2016 17:24:07 +0800 From: "Wang, Xiao W" <xiao.w.wang@intel.com> To: Thomas Monjalon <thomas.monjalon@6wind.com> Thread-Topic: [dpdk-dev] [PATCH v3 1/3] fm10k: enable FTAG based forwarding Thread-Index: AQHRXv2babUM9wifAkaFm8+HJNJY45867/aAgAAPUoCAASRUAIAAOwcAgAAkc4CAAAfsAIABMycA///npwCAAIggUA== Date: Fri, 26 Feb 2016 09:24:06 +0000 Message-ID: <B7F2E978279D1D49A3034B7786DACF403DBAD229@SHSMSX101.ccr.corp.intel.com> References: <1454410216-13333-2-git-send-email-xiao.w.wang@intel.com> <20160225161406.GA22772@bricha3-MOBL3> <B7F2E978279D1D49A3034B7786DACF403DBAD052@SHSMSX101.ccr.corp.intel.com> <4126401.C51dJZWCEs@xps13> In-Reply-To: <4126401.C51dJZWCEs@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: Fri, 26 Feb 2016 09:24:11 -0000 Hi, > -----Original Message----- > From: Thomas Monjalon [mailto:thomas.monjalon@6wind.com] > Sent: Friday, February 26, 2016 5:06 PM > To: Wang, Xiao W <xiao.w.wang@intel.com> > Cc: Richardson, Bruce <bruce.richardson@intel.com>; Chen, Jing D > <jing.d.chen@intel.com>; dev@dpdk.org > Subject: Re: [dpdk-dev] [PATCH v3 1/3] fm10k: enable FTAG based forwardin= g >=20 > 2016-02-26 04:31, Wang, Xiao W: > > From: Richardson, Bruce > > > On Thu, Feb 25, 2016 at 03:45:45PM +0000, Chen, Jing D wrote: > > > > From: Richardson, Bruce > > > > > On Thu, Feb 25, 2016 at 10:04:02AM +0000, Chen, Jing D wrote: > > > > > > 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. > > > > > > > > > > Why not just specify this in the port configuration at setup time= ? > > > > > > > > > > > > > Please educate me. I think the port configuration flags are also > > > > common to all PMD Drivers. Is it possible to add a flag like > "RTE_USE_FTAG" > > > and pass to PMD driver? > > > > > > > They are. > > > For something PMD specific, like FTAG, it's always a challenge, and > > > I don't know off the top of my head if there is a simple option. > > > However, given the choice between an mbuf flag and a port config > > > flag, I'd always choose the former. > > > Other alternatives would be to have a fm10k specific API in the > > > fm10k driver alone. > > > > > > I'll let Thomas as ethdev maintainer comment if he has other > > > suggestions as to how to handle this case. I suspect this won't be > > > the first device-specific piece of functionality we need to deal with= . > > > > > > /Bruce > > > > Whatever method we choose, we have to find a way for the user to > > express his need for FTAG, it maybe a build time config option, or a > > port config flag (no such flag now), or a fast path flag in mbuf (no > > such flag now) etc. For the customer Topsec's use case, they use FTAG > > for all the TX packets, so all the above methods (per build config, > > per port config, per mbuf config) can meet their need. Since the pmd > > frame work is for common, it's hard to add new fields only for one spec= ific > NIC, so I add a build time config and make an introduction in the doc. > > > > Thanks for the discussion, Thomas, do you have any suggestions? >=20 > I don't understand why you say this feature is specific to fm10k. Can we > imagine another NIC having this capability? As you know, fm10k has a switch logic between the Mac and Phy, every packet= s Sent out from the host will be switched inside the NIC, other NICs don't ha= ve a switch inside, and the FTAG feature is related to the switch function. As introduced in the second patch: The FM10K family of NICs support the addition of a Fabric Tag (FTAG) to car= ry special information. The FTAG is placed at the beginning of the frame, it c= ontains information such as where the packet comes from and goes, and the vlan tag.= In FTAG based forwarding mode, the switch logic forwards packets according to glort (global resource tag) information, rather than the mac and vlan table= . So this is a feature specific to fm10k. Best Regards, Xiao > I think it must be an port configuration, as Bruce suggested. > What about a field in struct rte_eth_conf?