From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: <stephen@networkplumber.org> Received: from mail-pa0-f44.google.com (mail-pa0-f44.google.com [209.85.220.44]) by dpdk.org (Postfix) with ESMTP id 2366B9E5 for <dev@dpdk.org>; Tue, 27 Oct 2015 00:47:10 +0100 (CET) Received: by pabla5 with SMTP id la5so9102458pab.0 for <dev@dpdk.org>; Mon, 26 Oct 2015 16:47:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=networkplumber_org.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:in-reply-to:references :mime-version:content-type:content-transfer-encoding; bh=mjFue5UPthsMLqVHa877guHHHpanpk57843mzjIBlu4=; b=FyG/UB9Q/vVWHiC5tLfPvYTTzr8HCVEtPZ1e8850yQilwWK5kC+gVKgezF5d2U8f+3 6sF1bl7qEqQp7kSmNPCytZNAgzcde7OfIVC2ydprRZ0ZjZRm/IJum+3ty92Jh8CEziDu fQDYrbe0jIcX/fgQaMNK8xcXLG/O0viEVyQh5CDYfNDYkBbU30U0r9rf6Oql9Iu33jXW h0dXwTmt270ajpr5XO1hvJ5zjdBeXv25V1A3+565YN4e9/lAiDUtW/n5JCyb4+yAV3Tb ueZpIcZxf8NMgwqgevNn11mnV1T6QBt6NlIzeoRoGgwQlsBIcwN/1XePZaM7XH2wXlaO ge3Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:mime-version:content-type:content-transfer-encoding; bh=mjFue5UPthsMLqVHa877guHHHpanpk57843mzjIBlu4=; b=jHGfKJ+UI11eyyq396C16RWQ8Hb7Ua0TbXXyswospASk6PQ01Q5YS4OD13Mgov+4M3 yZy+cLTJOk8Y9pJ39ISQnE5HHWvKKyeAFeTMCWk3PE/PTRyQ8+9WYKbi5KyLdSCRPbkF 4HwQ6L/V9RGup13KJg6b+/YNFZ/xRKfHtRpb0O46EqLczuDPvQMWKaZUSgCPc2wzpVKf zBJ3nYXkTZeWokCJgyaJiAo9uhq5rxG8i/idTyfyBQCv1g7mZ4SZd8QUyaErgCTQLGqQ 1Z9HsUrhp56IZo8Q4EgBol2FRkA9yWodBZFKqAT4sCGt46FJLwyH5o35HWzvAOykTA/t y3/w== X-Gm-Message-State: ALoCoQnCNqxSZbwlhmJ7IGzy3+THEL2nO/jZecroj9TIyPqLcuxyPSAgbltT7iRnn6wx4sr8omCs X-Received: by 10.66.90.231 with SMTP id bz7mr24190556pab.47.1445903229334; Mon, 26 Oct 2015 16:47:09 -0700 (PDT) Received: from samsung9 ([144.49.132.22]) by smtp.gmail.com with ESMTPSA id ve8sm35946199pbc.48.2015.10.26.16.47.08 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 26 Oct 2015 16:47:09 -0700 (PDT) Date: Tue, 27 Oct 2015 08:47:00 +0900 From: Stephen Hemminger <stephen@networkplumber.org> To: "Xie, Huawei" <huawei.xie@intel.com> Message-ID: <20151027084700.08d0b093@samsung9> In-Reply-To: <C37D651A908B024F974696C65296B57B4B12CE5D@SHSMSX101.ccr.corp.intel.com> References: <1445231772-17467-1-git-send-email-stephen@networkplumber.org> <1445231772-17467-5-git-send-email-stephen@networkplumber.org> <C37D651A908B024F974696C65296B57B4B12CC68@SHSMSX101.ccr.corp.intel.com> <20151019094316.1fffd775@xeon-e3> <C37D651A908B024F974696C65296B57B4B12CE5D@SHSMSX101.ccr.corp.intel.com> X-Mailer: Claws Mail 3.11.1 (GTK+ 2.24.25; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: "dev@dpdk.org" <dev@dpdk.org> Subject: Re: [dpdk-dev] [PATCH 4/5] virtio: use any layout on transmit 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: Mon, 26 Oct 2015 23:47:10 -0000 On Mon, 19 Oct 2015 16:56:02 +0000 "Xie, Huawei" <huawei.xie@intel.com> wrote: > On 10/20/2015 12:43 AM, Stephen Hemminger wrote: > > On Mon, 19 Oct 2015 16:28:30 +0000 > > "Xie, Huawei" <huawei.xie@intel.com> wrote: > > > >> On 10/19/2015 1:16 PM, Stephen Hemminger wrote: > >>> Virtio supports a feature that allows sender to put transmit > >>> header prepended to data. It requires that the mbuf be writeable, correct > >>> alignment, and the feature has been negotiatied. If all this works out, > >>> then it will be the optimum way to transmit a single segment packet. > >> "When using legacy interfaces, transitional drivers which have not > >> negotiated VIRTIO_F_ANY_LAYOUT > >> MUST use a single descriptor for the struct virtio_net_hdr on both > >> transmit and receive, with the > >> network data in the following descriptors." > > The code checks for the any layout feature, what is the problem? > My reply is removed. I said virtio RX is already implemented using this > feature by default without negotiation(at the time of implementation, no > idea of this feature), is the RX implementation wrong? > No receiver is fine, it is okay to handle it coming in as long as it doesn't assume that is the only possible layout.