From patchwork Wed Jan 16 02:13:42 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Hu, Jiayu" X-Patchwork-Id: 49864 X-Patchwork-Delegate: thomas@monjalon.net Return-Path: X-Original-To: patchwork@dpdk.org Delivered-To: patchwork@dpdk.org Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 48BD611C5; Wed, 16 Jan 2019 03:13:46 +0100 (CET) Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by dpdk.org (Postfix) with ESMTP id 1B1061150; Wed, 16 Jan 2019 03:13:44 +0100 (CET) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 15 Jan 2019 18:13:44 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,484,1539673200"; d="scan'208";a="114991219" Received: from dpdk15.sh.intel.com ([10.67.111.146]) by fmsmga007.fm.intel.com with ESMTP; 15 Jan 2019 18:13:43 -0800 From: Jiayu Hu To: dev@dpdk.org Cc: konstantin.ananyev@intel.com, thomas@monjalon.net, Jiayu Hu , stable@dpdk.org Date: Wed, 16 Jan 2019 10:13:42 +0800 Message-Id: <1547604822-9920-1-git-send-email-jiayu.hu@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1547021995-14231-1-git-send-email-jiayu.hu@intel.com> References: <1547021995-14231-1-git-send-email-jiayu.hu@intel.com> Subject: [dpdk-dev] [PATCH v6] doc: add GRO limitations in prog_guide X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" This patch adds GRO limitations in the programmer guide. Fixes: 2c900d09055e ("doc: add GRO guide") Cc: stable@dpdk.org Signed-off-by: Jiayu Hu Acked-by: Konstantin Ananyev --- changes in v6: - add VLAN limitation changes in v5: - remove fix commit 9e0b9d2ec0f4 changes in v4: - update MBUF->l2_len/... requirement changes in v3: - add MBUF limitation changes in v2: - add fix commits - add more limitations doc/guides/prog_guide/generic_receive_offload_lib.rst | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/doc/guides/prog_guide/generic_receive_offload_lib.rst b/doc/guides/prog_guide/generic_receive_offload_lib.rst index 9c6a4d0..5b3fb91 100644 --- a/doc/guides/prog_guide/generic_receive_offload_lib.rst +++ b/doc/guides/prog_guide/generic_receive_offload_lib.rst @@ -191,3 +191,22 @@ Header fields deciding if packets are neighbors include: ignore IPv4 ID fields for the packets whose DF bit is 1. Additionally, packets which have different value of DF bit can't be merged. + +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.