From patchwork Wed Jan 9 08:19:55 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Hu, Jiayu" X-Patchwork-Id: 49505 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 480301B1F2; Wed, 9 Jan 2019 09:20:08 +0100 (CET) Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by dpdk.org (Postfix) with ESMTP id B71FF1B1CE; Wed, 9 Jan 2019 09:20:06 +0100 (CET) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga107.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 09 Jan 2019 00:20:05 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,456,1539673200"; d="scan'208";a="125459403" Received: from dpdk15.sh.intel.com ([10.67.111.146]) by orsmga001.jf.intel.com with ESMTP; 09 Jan 2019 00:20:03 -0800 From: Jiayu Hu To: dev@dpdk.org Cc: konstantin.ananyev@intel.com, mb@smartsharesystems.com, stephen@networkplumber.org, thomas@monjalon.net, vipin.varghese@intel.com, Jiayu Hu , stable@dpdk.org Date: Wed, 9 Jan 2019 16:19:55 +0800 Message-Id: <1547021995-14231-1-git-send-email-jiayu.hu@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1547002811-6989-1-git-send-email-jiayu.hu@intel.com> References: <1547002811-6989-1-git-send-email-jiayu.hu@intel.com> Subject: [dpdk-dev] [PATCH v5] doc: add GRO API 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 API limitations in the programmer guide. Fixes: 2c900d09055e ("doc: add GRO guide") Cc: stable@dpdk.org Signed-off-by: Jiayu Hu --- 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 | 17 +++++++++++++++++ 1 file changed, 17 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..53c9d5c 100644 --- a/doc/guides/prog_guide/generic_receive_offload_lib.rst +++ b/doc/guides/prog_guide/generic_receive_offload_lib.rst @@ -191,3 +191,20 @@ 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 the values of MBUF->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 call GRO APIs to merge packets, user applications + must set MBUF->l2_len/l3_len/l4_len/outer_l2_len/outer_l3_len + to the same values as the protocol headers of the packet. + +- GRO library doesn't support to process packets with IPv4 Options. + +- 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.