From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas@monjalon.net>
Subject: Re: [dpdk-stable] [PATCH v6] doc: add GRO limitations in
	prog_guide
Date: Thu, 17 Jan 2019 23:08:07 +0100
Message-ID: <6102338.UvBRKH1dAI@xps>
References: <1547021995-14231-1-git-send-email-jiayu.hu@intel.com>
 <1547604822-9920-1-git-send-email-jiayu.hu@intel.com>
 <6DC05C7C5F25994B81B3F2F214251F660207DB1F@IRSMSX104.ger.corp.intel.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7Bit
Cc: stable@dpdk.org, "Kovacevic, Marko" <marko.kovacevic@intel.com>,
 "dev@dpdk.org" <dev@dpdk.org>, "Ananyev,
 Konstantin" <konstantin.ananyev@intel.com>
To: "Hu, Jiayu" <jiayu.hu@intel.com>
Return-path: <dev-bounces@dpdk.org>
In-Reply-To: <6DC05C7C5F25994B81B3F2F214251F660207DB1F@IRSMSX104.ger.corp.intel.com>
List-Id: DPDK patches and discussions <dev.dpdk.org>
List-Unsubscribe: <https://mails.dpdk.org/options/dev>,
 <mailto:dev-request@dpdk.org?subject=unsubscribe>
List-Archive: <http://mails.dpdk.org/archives/dev/>
List-Post: <mailto:dev@dpdk.org>
List-Help: <mailto:dev-request@dpdk.org?subject=help>
List-Subscribe: <https://mails.dpdk.org/listinfo/dev>,
 <mailto:dev-request@dpdk.org?subject=subscribe>
Errors-To: dev-bounces@dpdk.org
Sender: "dev" <dev-bounces@dpdk.org>

17/01/2019 14:55, Kovacevic, Marko:
> > +GRO Library Limitations
> > +-----------------------
> > +
> > +- GRO library uses MBUF->l2_len/l3_len/l4_len/outer_l2_len/
> > +  outer_l3_len/packet_type to get protocol headers for the
> > +  input packet, rather than parsing the packet header. Therefore,
> > +  before call GRO APIs to merge packets, user applications
> > +  must set MBUF->l2_len/l3_len/l4_len/outer_l2_len/outer_l3_len/
> > +  packet_type to the same values as the protocol headers of the
> > +  packet.
> > +
> > +- GRO library doesn't support to process the packets with IPv4
> > +  Options or VLAN tagged.
> > +
> > +- GRO library just supports to process the packet organized
> > +  in a single MBUF. If the input packet consists of multiple
> > +  MBUFs (i.e. chained MBUFs), GRO reassembly behaviors are
> > +  unknown.
> > --
> 
> Would it be better said like this ??
> 
> - GRO library uses different MBUF->packet_types for example
>   ``l2_len, l3_len, l4_len, outer_l2_len, outer_l3_len`` to get protocol
>   headers for the input packet, rather than parsing the packet header.
>   Therefore, before calling GRO APIs to merge packets, user applications
>   must set MBUF->packet_type to the same values as the protocol headers of
>   the packet.

packet_type is really a field in mbuf.
I think the wording from Jiayu is more correct.