From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <olivier.matz@6wind.com>
Received: from mail.droids-corp.org (zoll.droids-corp.org [94.23.50.67])
 by dpdk.org (Postfix) with ESMTP id E5DAF2951
 for <dev@dpdk.org>; Tue, 16 Jan 2018 11:42:47 +0100 (CET)
Received: from lfbn-lil-1-110-231.w90-45.abo.wanadoo.fr ([90.45.197.231]
 helo=droids-corp.org)
 by mail.droids-corp.org with esmtpsa (TLS1.0:RSA_AES_256_CBC_SHA1:256)
 (Exim 4.89) (envelope-from <olivier.matz@6wind.com>)
 id 1ebOhX-0008Cn-Q2; Tue, 16 Jan 2018 11:42:45 +0100
Received: by droids-corp.org (sSMTP sendmail emulation);
 Tue, 16 Jan 2018 11:42:38 +0100
Date: Tue, 16 Jan 2018 11:42:38 +0100
From: Olivier Matz <olivier.matz@6wind.com>
To: "Wang, Xiao W" <xiao.w.wang@intel.com>
Cc: "yliu@fridaylinux.org" <yliu@fridaylinux.org>,
 "thomas@monjalon.net" <thomas@monjalon.net>,
 "Bie, Tiwei" <tiwei.bie@intel.com>, "dev@dpdk.org" <dev@dpdk.org>,
 "stephen@networkplumber.org" <stephen@networkplumber.org>,
 "maxime.coquelin@redhat.com" <maxime.coquelin@redhat.com>
Message-ID: <20180116104238.n4uzmby46zlyogjn@platinum>
References: <20180109160918.29173-4-xiao.w.wang@intel.com>
 <20180110012356.57456-1-xiao.w.wang@intel.com>
 <20180110012356.57456-4-xiao.w.wang@intel.com>
 <20180116090122.fsvqrgzu5rjqcgre@platinum>
 <B7F2E978279D1D49A3034B7786DACF406F80E17A@SHSMSX101.ccr.corp.intel.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <B7F2E978279D1D49A3034B7786DACF406F80E17A@SHSMSX101.ccr.corp.intel.com>
User-Agent: NeoMutt/20170113 (1.7.2)
Subject: Re: [dpdk-dev] [PATCH v10 3/5] net: add a helper for making RARP
 packet
X-BeenThere: dev@dpdk.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: DPDK patches and discussions <dev.dpdk.org>
List-Unsubscribe: <https://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: <https://dpdk.org/ml/listinfo/dev>,
 <mailto:dev-request@dpdk.org?subject=subscribe>
X-List-Received-Date: Tue, 16 Jan 2018 10:42:48 -0000

Hi Xiao,

On Tue, Jan 16, 2018 at 09:43:43AM +0000, Wang, Xiao W wrote:
> Hi Olivier,
> > You can also use rte_pktmbuf_append() to check for the tailroom and
> > update data_len/pkt_len:
> > 
> > 	m = rte_pktmbuf_alloc();
> > 	if (m == NULL)
> > 		return NULL;
> > 	eth_hdr = rte_pktmbuf_append(m, RARP_PKT_SIZE);
> 
> When data_len is not enough, we need to rte_pktmbuf_append(m, RARP_PKT_SIZE - m->data_len);

Sorry, I don't get your point here.