From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jiayu Hu Subject: [PATCH v5] doc: add GRO API limitations in prog_guide Date: Wed, 9 Jan 2019 16:19:55 +0800 Message-ID: <1547021995-14231-1-git-send-email-jiayu.hu@intel.com> References: <1547002811-6989-1-git-send-email-jiayu.hu@intel.com> Cc: konstantin.ananyev@intel.com, mb@smartsharesystems.com, stephen@networkplumber.org, thomas@monjalon.net, vipin.varghese@intel.com, Jiayu Hu , stable@dpdk.org To: dev@dpdk.org Return-path: In-Reply-To: <1547002811-6989-1-git-send-email-jiayu.hu@intel.com> 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. -- 2.7.4