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{
    "id": 26169,
    "url": "https://patches.dpdk.org/api/patches/26169/?format=api",
    "web_url": "https://patches.dpdk.org/project/dpdk/patch/1498907323-17563-3-git-send-email-jiayu.hu@intel.com/",
    "project": {
        "id": 1,
        "url": "https://patches.dpdk.org/api/projects/1/?format=api",
        "name": "DPDK",
        "link_name": "dpdk",
        "list_id": "dev.dpdk.org",
        "list_email": "dev@dpdk.org",
        "web_url": "http://core.dpdk.org",
        "scm_url": "git://dpdk.org/dpdk",
        "webscm_url": "http://git.dpdk.org/dpdk",
        "list_archive_url": "https://inbox.dpdk.org/dev",
        "list_archive_url_format": "https://inbox.dpdk.org/dev/{}",
        "commit_url_format": ""
    },
    "msgid": "<1498907323-17563-3-git-send-email-jiayu.hu@intel.com>",
    "list_archive_url": "https://inbox.dpdk.org/dev/1498907323-17563-3-git-send-email-jiayu.hu@intel.com",
    "date": "2017-07-01T11:08:42",
    "name": "[dpdk-dev,v10,2/3] lib/gro: add TCP/IPv4 GRO support",
    "commit_ref": null,
    "pull_url": null,
    "state": "superseded",
    "archived": true,
    "hash": "b01bfb22109fa38c063687dbb5929c63285f8761",
    "submitter": {
        "id": 539,
        "url": "https://patches.dpdk.org/api/people/539/?format=api",
        "name": "Hu, Jiayu",
        "email": "jiayu.hu@intel.com"
    },
    "delegate": null,
    "mbox": "https://patches.dpdk.org/project/dpdk/patch/1498907323-17563-3-git-send-email-jiayu.hu@intel.com/mbox/",
    "series": [],
    "comments": "https://patches.dpdk.org/api/patches/26169/comments/",
    "check": "fail",
    "checks": "https://patches.dpdk.org/api/patches/26169/checks/",
    "tags": {},
    "related": [],
    "headers": {
        "Return-Path": "<dev-bounces@dpdk.org>",
        "X-Original-To": "patchwork@dpdk.org",
        "Delivered-To": "patchwork@dpdk.org",
        "Received": [
            "from [92.243.14.124] (localhost [IPv6:::1])\n\tby dpdk.org (Postfix) with ESMTP id 58DC25699;\n\tSat,  1 Jul 2017 13:07:27 +0200 (CEST)",
            "from mga06.intel.com (mga06.intel.com [134.134.136.31])\n\tby dpdk.org (Postfix) with ESMTP id 946F94C57\n\tfor <dev@dpdk.org>; Sat,  1 Jul 2017 13:07:24 +0200 (CEST)",
            "from fmsmga002.fm.intel.com ([10.253.24.26])\n\tby orsmga104.jf.intel.com with ESMTP; 01 Jul 2017 04:07:24 -0700",
            "from dpdk15.sh.intel.com ([10.67.111.77])\n\tby fmsmga002.fm.intel.com with ESMTP; 01 Jul 2017 04:07:22 -0700"
        ],
        "X-ExtLoop1": "1",
        "X-IronPort-AV": "E=Sophos; i=\"5.40,291,1496127600\"; d=\"scan'208\";\n\ta=\"1189364785\"",
        "From": "Jiayu Hu <jiayu.hu@intel.com>",
        "To": "dev@dpdk.org",
        "Cc": "konstantin.ananyev@intel.com, stephen@networkplumber.org,\n\tjianfeng.tan@intel.com, yliu@fridaylinux.org, jingjing.wu@intel.com, \n\tlei.a.yao@intel.com, tiwei.bie@intel.com, Jiayu Hu <jiayu.hu@intel.com>",
        "Date": "Sat,  1 Jul 2017 19:08:42 +0800",
        "Message-Id": "<1498907323-17563-3-git-send-email-jiayu.hu@intel.com>",
        "X-Mailer": "git-send-email 2.7.4",
        "In-Reply-To": "<1498907323-17563-1-git-send-email-jiayu.hu@intel.com>",
        "References": "<1498805618-63649-1-git-send-email-jiayu.hu@intel.com>\n\t<1498907323-17563-1-git-send-email-jiayu.hu@intel.com>",
        "Subject": "[dpdk-dev] [PATCH v10 2/3] lib/gro: add TCP/IPv4 GRO support",
        "X-BeenThere": "dev@dpdk.org",
        "X-Mailman-Version": "2.1.15",
        "Precedence": "list",
        "List-Id": "DPDK patches and discussions <dev.dpdk.org>",
        "List-Unsubscribe": "<http://dpdk.org/ml/options/dev>,\n\t<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": "<http://dpdk.org/ml/listinfo/dev>,\n\t<mailto:dev-request@dpdk.org?subject=subscribe>",
        "Errors-To": "dev-bounces@dpdk.org",
        "Sender": "\"dev\" <dev-bounces@dpdk.org>"
    },
    "content": "In this patch, we introduce five APIs to support TCP/IPv4 GRO.\n- gro_tcp4_tbl_create: create a TCP/IPv4 reassembly table, which is used\n    to merge packets.\n- gro_tcp4_tbl_destroy: free memory space of a TCP/IPv4 reassembly table.\n- gro_tcp4_tbl_timeout_flush: flush timeout packets from a TCP/IPv4\n    reassembly table.\n- gro_tcp4_tbl_item_num: return the number of packets in a TCP/IPv4\n    reassembly table.\n- gro_tcp4_reassemble: reassemble an inputted TCP/IPv4 packet.\n\nTCP/IPv4 GRO API assumes all inputted packets are with correct IPv4\nand TCP checksums. And TCP/IPv4 GRO API doesn't update IPv4 and TCP\nchecksums for merged packets. If inputted packets are IP fragmented,\nTCP/IPv4 GRO API assumes they are complete packets (i.e. with L4\nheaders).\n\nIn TCP/IPv4 GRO, we use a table structure, called TCP/IPv4 reassembly\ntable, to reassemble packets. A TCP/IPv4 reassembly table includes a key\narray and a item array, where the key array keeps the criteria to merge\npackets and the item array keeps packet information.\n\nOne key in the key array points to an item group, which consists of\npackets which have the same criteria value. If two packets are able to\nmerge, they must be in the same item group. Each key in the key array\nincludes two parts:\n- criteria: the criteria of merging packets. If two packets can be\n    merged, they must have the same criteria value.\n- start_index: the index of the first incoming packet of the item group.\n\nEach element in the item array keeps the information of one packet. It\nmainly includes two parts:\n- pkt: packet address\n- next_pkt_index: the index of the next packet in the same item group.\n    All packets in the same item group are chained by next_pkt_index.\n    With next_pkt_index, we can locate all packets in the same item\n    group one by one.\n\nTo process an incoming packet needs three steps:\na. check if the packet should be processed. Packets with one of the\n    following properties won't be processed:\n\t- SYN, FIN, RST or PSH bit is set;\n\t- packet payload length is 0.\nb. traverse the key array to find a key which has the same criteria\n    value with the incoming packet. If find, goto step c. Otherwise,\n    insert a new key and insert the packet into the item array.\nc. locate the first packet in the item group via the start_index in the\n    key. Then traverse all packets in the item group via next_pkt_index.\n    If find one packet which can merge with the incoming one, merge them\n    together. If can't find, insert the packet into this item group.\n\nSigned-off-by: Jiayu Hu <jiayu.hu@intel.com>\n---\n doc/guides/rel_notes/release_17_08.rst |   7 +\n lib/librte_gro/Makefile                |   1 +\n lib/librte_gro/rte_gro.c               | 123 ++++++++-\n lib/librte_gro/rte_gro.h               |  10 +-\n lib/librte_gro/rte_gro_tcp4.c          | 439 +++++++++++++++++++++++++++++++++\n lib/librte_gro/rte_gro_tcp4.h          | 172 +++++++++++++\n 6 files changed, 736 insertions(+), 16 deletions(-)\n create mode 100644 lib/librte_gro/rte_gro_tcp4.c\n create mode 100644 lib/librte_gro/rte_gro_tcp4.h",
    "diff": "diff --git a/doc/guides/rel_notes/release_17_08.rst b/doc/guides/rel_notes/release_17_08.rst\nindex 842f46f..f067247 100644\n--- a/doc/guides/rel_notes/release_17_08.rst\n+++ b/doc/guides/rel_notes/release_17_08.rst\n@@ -75,6 +75,13 @@ New Features\n \n   Added support for firmwares with multiple Ethernet ports per physical port.\n \n+* **Add Generic Receive Offload API support.**\n+\n+  Generic Receive Offload (GRO) API supports to reassemble TCP/IPv4\n+  packets. GRO API assumes all inputted packets are with correct\n+  checksums. GRO API doesn't update checksums for merged packets. If\n+  inputted packets are IP fragmented, GRO API assumes they are complete\n+  packets (i.e. with L4 headers).\n \n Resolved Issues\n ---------------\ndiff --git a/lib/librte_gro/Makefile b/lib/librte_gro/Makefile\nindex 7e0f128..43e276e 100644\n--- a/lib/librte_gro/Makefile\n+++ b/lib/librte_gro/Makefile\n@@ -43,6 +43,7 @@ LIBABIVER := 1\n \n # source files\n SRCS-$(CONFIG_RTE_LIBRTE_GRO) += rte_gro.c\n+SRCS-$(CONFIG_RTE_LIBRTE_GRO) += rte_gro_tcp4.c\n \n # install this header file\n SYMLINK-$(CONFIG_RTE_LIBRTE_GRO)-include += rte_gro.h\ndiff --git a/lib/librte_gro/rte_gro.c b/lib/librte_gro/rte_gro.c\nindex 648835b..a4641f9 100644\n--- a/lib/librte_gro/rte_gro.c\n+++ b/lib/librte_gro/rte_gro.c\n@@ -32,8 +32,11 @@\n \n #include <rte_malloc.h>\n #include <rte_mbuf.h>\n+#include <rte_cycles.h>\n+#include <rte_ethdev.h>\n \n #include \"rte_gro.h\"\n+#include \"rte_gro_tcp4.h\"\n \n typedef void *(*gro_tbl_create_fn)(uint16_t socket_id,\n \t\tuint16_t max_flow_num,\n@@ -41,9 +44,12 @@ typedef void *(*gro_tbl_create_fn)(uint16_t socket_id,\n typedef void (*gro_tbl_destroy_fn)(void *tbl);\n typedef uint32_t (*gro_tbl_item_num_fn)(void *tbl);\n \n-static gro_tbl_create_fn tbl_create_functions[RTE_GRO_TYPE_MAX_NUM];\n-static gro_tbl_destroy_fn tbl_destroy_functions[RTE_GRO_TYPE_MAX_NUM];\n-static gro_tbl_item_num_fn tbl_item_num_functions[RTE_GRO_TYPE_MAX_NUM];\n+static gro_tbl_create_fn tbl_create_functions[RTE_GRO_TYPE_MAX_NUM] = {\n+\tgro_tcp4_tbl_create, NULL};\n+static gro_tbl_destroy_fn tbl_destroy_functions[RTE_GRO_TYPE_MAX_NUM] = {\n+\tgro_tcp4_tbl_destroy, NULL};\n+static gro_tbl_item_num_fn tbl_item_num_functions[\n+\tRTE_GRO_TYPE_MAX_NUM] = {gro_tcp4_tbl_item_num, NULL};\n \n /**\n  * GRO table, which is used to merge packets. It keeps many reassembly\n@@ -130,27 +136,118 @@ void rte_gro_tbl_destroy(void *tbl)\n }\n \n uint16_t\n-rte_gro_reassemble_burst(struct rte_mbuf **pkts __rte_unused,\n+rte_gro_reassemble_burst(struct rte_mbuf **pkts,\n \t\tuint16_t nb_pkts,\n-\t\tconst struct rte_gro_param *param __rte_unused)\n+\t\tconst struct rte_gro_param *param)\n {\n-\treturn nb_pkts;\n+\tuint16_t i;\n+\tuint16_t nb_after_gro = nb_pkts;\n+\tuint32_t item_num;\n+\n+\t/* allocate a reassembly table for TCP/IPv4 GRO */\n+\tstruct gro_tcp4_tbl tcp_tbl;\n+\tstruct gro_tcp4_key tcp_keys[RTE_GRO_MAX_BURST_ITEM_NUM] = {0};\n+\tstruct gro_tcp4_item tcp_items[RTE_GRO_MAX_BURST_ITEM_NUM] = {0};\n+\n+\tstruct rte_mbuf *unprocess_pkts[nb_pkts];\n+\tuint16_t unprocess_num = 0;\n+\tint32_t ret;\n+\tuint64_t current_time;\n+\n+\tif ((param->desired_gro_types & RTE_GRO_TCP_IPV4) == 0)\n+\t\treturn nb_pkts;\n+\n+\t/* get the actual number of items */\n+\titem_num = RTE_MIN(nb_pkts, (param->max_flow_num *\n+\t\t\tparam->max_item_per_flow));\n+\titem_num = RTE_MIN(item_num, RTE_GRO_MAX_BURST_ITEM_NUM);\n+\n+\ttcp_tbl.keys = tcp_keys;\n+\ttcp_tbl.items = tcp_items;\n+\ttcp_tbl.key_num = 0;\n+\ttcp_tbl.item_num = 0;\n+\ttcp_tbl.max_key_num = item_num;\n+\ttcp_tbl.max_item_num = item_num;\n+\n+\tcurrent_time = rte_rdtsc();\n+\n+\tfor (i = 0; i < nb_pkts; i++) {\n+\t\tif (RTE_ETH_IS_IPV4_HDR(pkts[i]->packet_type) &&\n+\t\t\t\t(pkts[i]->packet_type & RTE_PTYPE_L4_TCP)) {\n+\t\t\tret = gro_tcp4_reassemble(pkts[i],\n+\t\t\t\t\t&tcp_tbl,\n+\t\t\t\t\tparam->max_packet_size,\n+\t\t\t\t\tcurrent_time);\n+\t\t\tif (ret > 0)\n+\t\t\t\t/* merge successfully */\n+\t\t\t\tnb_after_gro--;\n+\t\t\telse if (ret < 0)\n+\t\t\t\tunprocess_pkts[unprocess_num++] =\n+\t\t\t\t\tpkts[i];\n+\t\t} else\n+\t\t\tunprocess_pkts[unprocess_num++] =\n+\t\t\t\tpkts[i];\n+\t}\n+\n+\t/* re-arrange GROed packets */\n+\tif (nb_after_gro < nb_pkts) {\n+\t\ti = gro_tcp4_tbl_timeout_flush(&tcp_tbl, 0,\n+\t\t\t\tpkts, nb_pkts);\n+\t\tif (unprocess_num > 0)\n+\t\t\tmemcpy(&pkts[i], unprocess_pkts,\n+\t\t\t\t\tsizeof(struct rte_mbuf *) *\n+\t\t\t\t\tunprocess_num);\n+\t}\n+\treturn nb_after_gro;\n }\n \n uint16_t\n-rte_gro_reassemble(struct rte_mbuf **pkts __rte_unused,\n+rte_gro_reassemble(struct rte_mbuf **pkts,\n \t\tuint16_t nb_pkts,\n-\t\tvoid *tbl __rte_unused)\n+\t\tvoid *tbl)\n {\n-\treturn nb_pkts;\n+\tuint16_t i, unprocess_num = 0;\n+\tstruct rte_mbuf *unprocess_pkts[nb_pkts];\n+\tstruct gro_tbl *gro_tbl = (struct gro_tbl *)tbl;\n+\tuint64_t current_time;\n+\n+\tif ((gro_tbl->desired_gro_types & RTE_GRO_TCP_IPV4) == 0)\n+\t\treturn nb_pkts;\n+\n+\tcurrent_time = rte_rdtsc();\n+\tfor (i = 0; i < nb_pkts; i++) {\n+\t\tif (RTE_ETH_IS_IPV4_HDR(pkts[i]->packet_type) &&\n+\t\t\t\t(pkts[i]->packet_type & RTE_PTYPE_L4_TCP)) {\n+\t\t\tif (gro_tcp4_reassemble(pkts[i],\n+\t\t\t\t\t\tgro_tbl->tbls[RTE_GRO_TCP_IPV4_INDEX],\n+\t\t\t\t\t\tgro_tbl->max_packet_size,\n+\t\t\t\t\t\tcurrent_time) < 0)\n+\t\t\t\tunprocess_pkts[unprocess_num++] = pkts[i];\n+\t\t} else\n+\t\t\tunprocess_pkts[unprocess_num++] = pkts[i];\n+\t}\n+\tif (unprocess_num > 0)\n+\t\tmemcpy(pkts, unprocess_pkts,\n+\t\t\t\tsizeof(struct rte_mbuf *) * unprocess_num);\n+\n+\treturn unprocess_num;\n }\n \n uint16_t\n-rte_gro_timeout_flush(void *tbl __rte_unused,\n-\t\tuint64_t desired_gro_types __rte_unused,\n-\t\tstruct rte_mbuf **out __rte_unused,\n-\t\tuint16_t max_nb_out __rte_unused)\n+rte_gro_timeout_flush(void *tbl,\n+\t\tuint64_t desired_gro_types,\n+\t\tstruct rte_mbuf **out,\n+\t\tuint16_t max_nb_out)\n {\n+\tstruct gro_tbl *gro_tbl = (struct gro_tbl *)tbl;\n+\n+\tdesired_gro_types = desired_gro_types &\n+\t\tgro_tbl->desired_gro_types;\n+\tif (desired_gro_types & RTE_GRO_TCP_IPV4)\n+\t\treturn gro_tcp4_tbl_timeout_flush(\n+\t\t\t\tgro_tbl->tbls[RTE_GRO_TCP_IPV4_INDEX],\n+\t\t\t\tgro_tbl->max_timeout_cycles,\n+\t\t\t\tout, max_nb_out);\n \treturn 0;\n }\n \ndiff --git a/lib/librte_gro/rte_gro.h b/lib/librte_gro/rte_gro.h\nindex 02c9113..68d2fc6 100644\n--- a/lib/librte_gro/rte_gro.h\n+++ b/lib/librte_gro/rte_gro.h\n@@ -45,7 +45,11 @@ extern \"C\" {\n \n /* max number of supported GRO types */\n #define RTE_GRO_TYPE_MAX_NUM 64\n-#define RTE_GRO_TYPE_SUPPORT_NUM 0\t/**< current supported GRO num */\n+#define RTE_GRO_TYPE_SUPPORT_NUM 1\t/**< current supported GRO num */\n+\n+/* TCP/IPv4 GRO flag */\n+#define RTE_GRO_TCP_IPV4_INDEX 0\n+#define RTE_GRO_TCP_IPV4 (1ULL << RTE_GRO_TCP_IPV4_INDEX)\n \n \n struct rte_gro_param {\n@@ -118,14 +122,14 @@ uint16_t rte_gro_reassemble_burst(struct rte_mbuf **pkts,\n  *\n  * @param pkts\n  *  packet to reassemble. Besides, after this function finishes, it\n- *  keeps the unprocessed packets (i.e. without data or unsupported\n+ *  keeps the unprocessed packets (e.g. without data or unsupported\n  *  GRO types).\n  * @param nb_pkts\n  *  the number of packets to reassemble.\n  * @param tbl\n  *  a pointer points to a GRO table.\n  * @return\n- *  return the number of unprocessed packets (i.e. without data or\n+ *  return the number of unprocessed packets (e.g. without data or\n  *  unsupported GRO types). If all packets are processed (merged or\n  *  inserted into the table), return 0.\n  */\ndiff --git a/lib/librte_gro/rte_gro_tcp4.c b/lib/librte_gro/rte_gro_tcp4.c\nnew file mode 100644\nindex 0000000..8f2aa86\n--- /dev/null\n+++ b/lib/librte_gro/rte_gro_tcp4.c\n@@ -0,0 +1,439 @@\n+/*-\n+ *   BSD LICENSE\n+ *\n+ *   Copyright(c) 2017 Intel Corporation. All rights reserved.\n+ *\n+ *   Redistribution and use in source and binary forms, with or without\n+ *   modification, are permitted provided that the following conditions\n+ *   are met:\n+ *\n+ *     * Redistributions of source code must retain the above copyright\n+ *       notice, this list of conditions and the following disclaimer.\n+ *     * Redistributions in binary form must reproduce the above copyright\n+ *       notice, this list of conditions and the following disclaimer in\n+ *       the documentation and/or other materials provided with the\n+ *       distribution.\n+ *     * Neither the name of Intel Corporation nor the names of its\n+ *       contributors may be used to endorse or promote products derived\n+ *       from this software without specific prior written permission.\n+ *\n+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS\n+ *   \"AS IS\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT\n+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR\n+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT\n+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,\n+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT\n+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,\n+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY\n+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT\n+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE\n+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.\n+ */\n+\n+#include <rte_malloc.h>\n+#include <rte_mbuf.h>\n+#include <rte_cycles.h>\n+\n+#include <rte_ethdev.h>\n+#include <rte_ip.h>\n+#include <rte_tcp.h>\n+\n+#include \"rte_gro_tcp4.h\"\n+\n+void *gro_tcp4_tbl_create(uint16_t socket_id,\n+\t\tuint16_t max_flow_num,\n+\t\tuint16_t max_item_per_flow)\n+{\n+\tsize_t size;\n+\tuint32_t entries_num;\n+\tstruct gro_tcp4_tbl *tbl;\n+\n+\tentries_num = max_flow_num * max_item_per_flow;\n+\tentries_num = entries_num > GRO_TCP4_TBL_MAX_ITEM_NUM ?\n+\t\tGRO_TCP4_TBL_MAX_ITEM_NUM : entries_num;\n+\n+\tif (entries_num == 0)\n+\t\treturn NULL;\n+\n+\ttbl = (struct gro_tcp4_tbl *)rte_zmalloc_socket(\n+\t\t\t__func__,\n+\t\t\tsizeof(struct gro_tcp4_tbl),\n+\t\t\tRTE_CACHE_LINE_SIZE,\n+\t\t\tsocket_id);\n+\tif (tbl == NULL)\n+\t\treturn NULL;\n+\n+\tsize = sizeof(struct gro_tcp4_item) * entries_num;\n+\ttbl->items = (struct gro_tcp4_item *)rte_zmalloc_socket(\n+\t\t\t__func__,\n+\t\t\tsize,\n+\t\t\tRTE_CACHE_LINE_SIZE,\n+\t\t\tsocket_id);\n+\tif (tbl->items == NULL) {\n+\t\trte_free(tbl);\n+\t\treturn NULL;\n+\t}\n+\ttbl->max_item_num = entries_num;\n+\n+\tsize = sizeof(struct gro_tcp4_key) * entries_num;\n+\ttbl->keys = (struct gro_tcp4_key *)rte_zmalloc_socket(\n+\t\t\t__func__,\n+\t\t\tsize, RTE_CACHE_LINE_SIZE,\n+\t\t\tsocket_id);\n+\tif (tbl->keys == NULL) {\n+\t\trte_free(tbl->items);\n+\t\trte_free(tbl);\n+\t\treturn NULL;\n+\t}\n+\ttbl->max_key_num = entries_num;\n+\treturn tbl;\n+}\n+\n+void gro_tcp4_tbl_destroy(void *tbl)\n+{\n+\tstruct gro_tcp4_tbl *tcp_tbl = (struct gro_tcp4_tbl *)tbl;\n+\n+\tif (tcp_tbl) {\n+\t\trte_free(tcp_tbl->items);\n+\t\trte_free(tcp_tbl->keys);\n+\t}\n+\trte_free(tcp_tbl);\n+}\n+\n+static struct rte_mbuf *get_mbuf_lastseg(struct rte_mbuf *pkt)\n+{\n+\tstruct rte_mbuf *lastseg = pkt;\n+\n+\twhile (lastseg->next)\n+\t\tlastseg = lastseg->next;\n+\n+\treturn lastseg;\n+}\n+\n+/**\n+ * merge two TCP/IPv4 packets without updating checksums.\n+ */\n+static int\n+merge_two_tcp4_packets(struct gro_tcp4_item *item_src,\n+\t\tstruct rte_mbuf *pkt,\n+\t\tuint32_t max_packet_size,\n+\t\tint cmp)\n+{\n+\tstruct rte_mbuf *pkt_head, *pkt_tail, *lastseg;\n+\tstruct ipv4_hdr *ipv4_hdr1, *ipv4_hdr0;\n+\tuint16_t tcp_dl1;\n+\n+\tif (cmp > 0) {\n+\t\t/* append the new packet into tail */\n+\t\tpkt_head = item_src->pkt;\n+\t\tpkt_tail = pkt;\n+\t} else {\n+\t\t/* append the new packet into head */\n+\t\tpkt_head = pkt;\n+\t\tpkt_tail = item_src->pkt;\n+\t}\n+\n+\t/* parse the tail packet */\n+\tipv4_hdr1 = (struct ipv4_hdr *)(rte_pktmbuf_mtod(pkt_tail,\n+\t\t\t\tchar *) + pkt_tail->l2_len);\n+\ttcp_dl1 = rte_be_to_cpu_16(ipv4_hdr1->total_length) -\n+\t\tpkt_tail->l3_len - pkt_tail->l4_len;\n+\n+\tif (pkt_head->pkt_len + tcp_dl1 > max_packet_size)\n+\t\treturn -1;\n+\n+\t/* remove packet header for the tail packet */\n+\trte_pktmbuf_adj(pkt_tail, pkt_tail->l2_len +\n+\t\t\tpkt_tail->l3_len +\n+\t\t\tpkt_tail->l4_len);\n+\n+\tif (cmp > 0) {\n+\t\t/* chain the new packet to the tail of the original packet */\n+\t\titem_src->lastseg->next = pkt_tail;\n+\t\t/* update the lastseg for the item */\n+\t\titem_src->lastseg = get_mbuf_lastseg(pkt_tail);\n+\t} else {\n+\t\t/* chain the original packet to the tail of the new packet */\n+\t\tlastseg = get_mbuf_lastseg(pkt_head);\n+\t\tlastseg->next = pkt_tail;\n+\t\t/* update the item */\n+\t\titem_src->pkt = pkt_head;\n+\t}\n+\n+\t/* parse the head packet */\n+\tipv4_hdr0 = (struct ipv4_hdr *)(rte_pktmbuf_mtod(pkt_head,\n+\t\t\t\tchar *) + pkt_head->l2_len);\n+\n+\t/* update IP header for the head packet */\n+\tipv4_hdr0->total_length = rte_cpu_to_be_16(\n+\t\t\trte_be_to_cpu_16(\n+\t\t\t\tipv4_hdr0->total_length)\n+\t\t\t+ tcp_dl1);\n+\tipv4_hdr0->packet_id = ipv4_hdr1->packet_id;\n+\n+\t/* update mbuf metadata for the merged packet */\n+\tpkt_head->nb_segs += pkt_tail->nb_segs;\n+\tpkt_head->pkt_len += pkt_tail->pkt_len;\n+\treturn 1;\n+}\n+\n+static int\n+check_seq_option(struct rte_mbuf *pkt,\n+\t\tstruct tcp_hdr *tcp_hdr,\n+\t\tuint16_t ip_id,\n+\t\tuint16_t tcp_hl,\n+\t\tuint16_t tcp_dl)\n+{\n+\tstruct ipv4_hdr *ipv4_hdr0;\n+\tstruct tcp_hdr *tcp_hdr0;\n+\tuint16_t tcp_hl0, tcp_dl0, ip_id0;\n+\tuint32_t sent_seq0, sent_seq;\n+\tuint16_t len;\n+\n+\tipv4_hdr0 = (struct ipv4_hdr *)(rte_pktmbuf_mtod(pkt,\n+\t\t\t\tchar *) + pkt->l2_len);\n+\ttcp_hdr0 = (struct tcp_hdr *)((char *)ipv4_hdr0 + pkt->l3_len);\n+\n+\tip_id0 = rte_be_to_cpu_16(ipv4_hdr0->packet_id);\n+\ttcp_hl0 = pkt->l4_len;\n+\ttcp_dl0 = rte_be_to_cpu_16(ipv4_hdr0->total_length) -\n+\t\tpkt->l3_len - tcp_hl0;\n+\n+\t/* check if TCP option fields equal. If not, return 0. */\n+\tlen = RTE_MAX(tcp_hl, tcp_hl0) - sizeof(struct tcp_hdr);\n+\tif ((tcp_hl != tcp_hl0) || ((len > 0) &&\n+\t\t\t\t(memcmp(tcp_hdr + 1,\n+\t\t\t\t\t\ttcp_hdr0 + 1,\n+\t\t\t\t\t\tlen) != 0)))\n+\t\treturn 0;\n+\n+\t/* check if the two packets are neighbors */\n+\tsent_seq0 = rte_be_to_cpu_32(tcp_hdr0->sent_seq);\n+\tsent_seq = rte_be_to_cpu_32(tcp_hdr->sent_seq);\n+\n+\tif ((sent_seq == (sent_seq0 + tcp_dl0)) &&\n+\t\t\t(ip_id == (ip_id0 + 1)))\n+\t\t/* append the new packet into tail */\n+\t\treturn 1;\n+\telse if (((sent_seq + tcp_dl) == sent_seq0) &&\n+\t\t((ip_id + 1) == ip_id0))\n+\t\t/* append the new packet into head */\n+\t\treturn -1;\n+\telse\n+\t\treturn 0;\n+}\n+\n+static uint32_t\n+find_an_empty_item(struct gro_tcp4_tbl *tbl)\n+{\n+\tuint32_t i;\n+\n+\tfor (i = 0; i < tbl->max_item_num; i++)\n+\t\tif (tbl->items[i].pkt == NULL)\n+\t\t\treturn i;\n+\treturn INVALID_ARRAY_INDEX;\n+}\n+\n+static uint32_t\n+find_an_empty_key(struct gro_tcp4_tbl *tbl)\n+{\n+\tuint32_t i;\n+\n+\tfor (i = 0; i < tbl->max_key_num; i++)\n+\t\tif (tbl->keys[i].is_valid == 0)\n+\t\t\treturn i;\n+\treturn INVALID_ARRAY_INDEX;\n+}\n+\n+int32_t\n+gro_tcp4_reassemble(struct rte_mbuf *pkt,\n+\t\tstruct gro_tcp4_tbl *tbl,\n+\t\tuint32_t max_packet_size,\n+\t\tuint64_t start_time)\n+{\n+\tstruct ether_hdr *eth_hdr;\n+\tstruct ipv4_hdr *ipv4_hdr;\n+\tstruct tcp_hdr *tcp_hdr;\n+\tuint16_t tcp_dl, ip_id;\n+\n+\tstruct tcp4_key key;\n+\tuint32_t cur_idx, prev_idx, item_idx;\n+\tuint32_t i, key_idx;\n+\tint cmp;\n+\n+\teth_hdr = rte_pktmbuf_mtod(pkt, struct ether_hdr *);\n+\tipv4_hdr = (struct ipv4_hdr *)((char *)eth_hdr + pkt->l2_len);\n+\n+\t/* check if the packet should be processed */\n+\tif (pkt->l3_len < sizeof(struct ipv4_hdr))\n+\t\treturn -1;\n+\ttcp_hdr = (struct tcp_hdr *)((char *)ipv4_hdr + pkt->l3_len);\n+\t/* if SYN, FIN, RST, PSH or URG is set, return immediately */\n+\tif ((tcp_hdr->tcp_flags & (~((uint8_t)TCP_ACK_FLAG))) ||\n+\t\t\t((tcp_hdr->tcp_flags & TCP_ACK_FLAG) == 0))\n+\t\treturn -1;\n+\ttcp_dl = rte_be_to_cpu_16(ipv4_hdr->total_length) - pkt->l3_len\n+\t\t- pkt->l4_len;\n+\tif (tcp_dl == 0)\n+\t\treturn -1;\n+\n+\tip_id = rte_be_to_cpu_16(ipv4_hdr->packet_id);\n+\n+\t/* find a key and traverse all packets in its item group */\n+\tkey.eth_saddr = eth_hdr->s_addr;\n+\tkey.eth_daddr = eth_hdr->d_addr;\n+\tkey.ip_src_addr = rte_be_to_cpu_32(ipv4_hdr->src_addr);\n+\tkey.ip_dst_addr = rte_be_to_cpu_32(ipv4_hdr->dst_addr);\n+\tkey.src_port = rte_be_to_cpu_16(tcp_hdr->src_port);\n+\tkey.dst_port = rte_be_to_cpu_16(tcp_hdr->dst_port);\n+\tkey.recv_ack = rte_be_to_cpu_32(tcp_hdr->recv_ack);\n+\n+\tfor (i = 0; i < tbl->max_key_num; i++) {\n+\t\t/* search for a key */\n+\t\tif ((tbl->keys[i].is_valid == 0) ||\n+\t\t\t\t(memcmp(&(tbl->keys[i].key), &key,\n+\t\t\t\t\t\tsizeof(struct tcp4_key)) != 0))\n+\t\t\tcontinue;\n+\n+\t\tcur_idx = tbl->keys[i].start_index;\n+\t\tprev_idx = cur_idx;\n+\t\twhile (cur_idx != INVALID_ARRAY_INDEX) {\n+\t\t\tcmp = check_seq_option(tbl->items[cur_idx].pkt,\n+\t\t\t\t\ttcp_hdr,\n+\t\t\t\t\tip_id,\n+\t\t\t\t\tpkt->l4_len,\n+\t\t\t\t\ttcp_dl);\n+\t\t\tif (cmp != 0) {\n+\t\t\t\tif (merge_two_tcp4_packets(\n+\t\t\t\t\t\t\t&(tbl->items[cur_idx]),\n+\t\t\t\t\t\t\tpkt,\n+\t\t\t\t\t\t\tmax_packet_size,\n+\t\t\t\t\t\t\tcmp) > 0)\n+\t\t\t\t\treturn 1;\n+\t\t\t\t/**\n+\t\t\t\t * fail to merge two packets since\n+\t\t\t\t * it's beyond the max packet length.\n+\t\t\t\t * Insert it into the item group.\n+\t\t\t\t */\n+\t\t\t\titem_idx = find_an_empty_item(tbl);\n+\t\t\t\tif (item_idx == INVALID_ARRAY_INDEX)\n+\t\t\t\t\treturn -1;\n+\t\t\t\ttbl->items[prev_idx].next_pkt_idx = item_idx;\n+\t\t\t\ttbl->items[item_idx].pkt = pkt;\n+\t\t\t\ttbl->items[item_idx].lastseg =\n+\t\t\t\t\tget_mbuf_lastseg(pkt);\n+\t\t\t\ttbl->items[item_idx].next_pkt_idx =\n+\t\t\t\t\tINVALID_ARRAY_INDEX;\n+\t\t\t\ttbl->items[item_idx].start_time = start_time;\n+\t\t\t\ttbl->item_num++;\n+\t\t\t\treturn 0;\n+\t\t\t}\n+\t\t\tprev_idx = cur_idx;\n+\t\t\tcur_idx = tbl->items[cur_idx].next_pkt_idx;\n+\t\t}\n+\t\t/**\n+\t\t * find a corresponding item group but fails to find\n+\t\t * one packet to merge. Insert it into this item group.\n+\t\t */\n+\t\titem_idx = find_an_empty_item(tbl);\n+\t\tif (item_idx == INVALID_ARRAY_INDEX)\n+\t\t\treturn -1;\n+\t\ttbl->items[prev_idx].next_pkt_idx = item_idx;\n+\t\ttbl->items[item_idx].pkt = pkt;\n+\t\ttbl->items[item_idx].lastseg =\n+\t\t\tget_mbuf_lastseg(pkt);\n+\t\ttbl->items[item_idx].next_pkt_idx = INVALID_ARRAY_INDEX;\n+\t\ttbl->items[item_idx].start_time = start_time;\n+\t\ttbl->item_num++;\n+\t\treturn 0;\n+\t}\n+\n+\t/**\n+\t * merge fail as the given packet has\n+\t * a new key. So insert a new key.\n+\t */\n+\titem_idx = find_an_empty_item(tbl);\n+\tkey_idx = find_an_empty_key(tbl);\n+\t/**\n+\t * if current key or item number is greater than the max\n+\t * value, don't insert the packet into the table and return\n+\t * immediately.\n+\t */\n+\tif (item_idx == INVALID_ARRAY_INDEX ||\n+\t\t\tkey_idx == INVALID_ARRAY_INDEX)\n+\t\treturn -1;\n+\ttbl->items[item_idx].pkt = pkt;\n+\ttbl->items[item_idx].lastseg = get_mbuf_lastseg(pkt);\n+\ttbl->items[item_idx].next_pkt_idx = INVALID_ARRAY_INDEX;\n+\ttbl->items[item_idx].start_time = start_time;\n+\ttbl->item_num++;\n+\n+\tmemcpy(&(tbl->keys[key_idx].key),\n+\t\t\t&key, sizeof(struct tcp4_key));\n+\ttbl->keys[key_idx].start_index = item_idx;\n+\ttbl->keys[key_idx].is_valid = 1;\n+\ttbl->key_num++;\n+\n+\treturn 0;\n+}\n+\n+uint16_t\n+gro_tcp4_tbl_timeout_flush(struct gro_tcp4_tbl *tbl,\n+\t\tuint64_t timeout_cycles,\n+\t\tstruct rte_mbuf **out,\n+\t\tuint16_t nb_out)\n+{\n+\tuint16_t k = 0;\n+\tuint32_t i, j;\n+\tuint64_t current_time;\n+\n+\tcurrent_time = rte_rdtsc();\n+\tfor (i = 0; i < tbl->max_key_num; i++) {\n+\t\t/* all keys have been checked, return immediately */\n+\t\tif (tbl->key_num == 0)\n+\t\t\treturn k;\n+\n+\t\tif (tbl->keys[i].is_valid == 0)\n+\t\t\tcontinue;\n+\n+\t\tj = tbl->keys[i].start_index;\n+\t\twhile (j != INVALID_ARRAY_INDEX) {\n+\t\t\tif (current_time - tbl->items[j].start_time >=\n+\t\t\t\t\ttimeout_cycles) {\n+\t\t\t\tout[k++] = tbl->items[j].pkt;\n+\t\t\t\ttbl->items[j].pkt = NULL;\n+\t\t\t\ttbl->item_num--;\n+\t\t\t\tj = tbl->items[j].next_pkt_idx;\n+\n+\t\t\t\t/**\n+\t\t\t\t * delete the key as all of\n+\t\t\t\t * its packets are flushed.\n+\t\t\t\t */\n+\t\t\t\tif (j == INVALID_ARRAY_INDEX) {\n+\t\t\t\t\ttbl->keys[i].is_valid = 0;\n+\t\t\t\t\ttbl->key_num--;\n+\t\t\t\t} else\n+\t\t\t\t\t/* update start_index of the key */\n+\t\t\t\t\ttbl->keys[i].start_index = j;\n+\n+\t\t\t\tif (k == nb_out)\n+\t\t\t\t\treturn k;\n+\t\t\t} else\n+\t\t\t\t/**\n+\t\t\t\t * left packets of this key won't be\n+\t\t\t\t * timeout, so go to check other keys.\n+\t\t\t\t */\n+\t\t\t\tbreak;\n+\t\t}\n+\t}\n+\treturn k;\n+}\n+\n+uint32_t gro_tcp4_tbl_item_num(void *tbl)\n+{\n+\tstruct gro_tcp4_tbl *gro_tbl = (struct gro_tcp4_tbl *)tbl;\n+\n+\tif (gro_tbl)\n+\t\treturn gro_tbl->item_num;\n+\treturn 0;\n+}\ndiff --git a/lib/librte_gro/rte_gro_tcp4.h b/lib/librte_gro/rte_gro_tcp4.h\nnew file mode 100644\nindex 0000000..27856f8\n--- /dev/null\n+++ b/lib/librte_gro/rte_gro_tcp4.h\n@@ -0,0 +1,172 @@\n+/*-\n+ *   BSD LICENSE\n+ *\n+ *   Copyright(c) 2017 Intel Corporation. All rights reserved.\n+ *\n+ *   Redistribution and use in source and binary forms, with or without\n+ *   modification, are permitted provided that the following conditions\n+ *   are met:\n+ *\n+ *     * Redistributions of source code must retain the above copyright\n+ *       notice, this list of conditions and the following disclaimer.\n+ *     * Redistributions in binary form must reproduce the above copyright\n+ *       notice, this list of conditions and the following disclaimer in\n+ *       the documentation and/or other materials provided with the\n+ *       distribution.\n+ *     * Neither the name of Intel Corporation nor the names of its\n+ *       contributors may be used to endorse or promote products derived\n+ *       from this software without specific prior written permission.\n+ *\n+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS\n+ *   \"AS IS\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT\n+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR\n+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT\n+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,\n+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT\n+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,\n+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY\n+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT\n+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE\n+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.\n+ */\n+\n+#ifndef _RTE_GRO_TCP4_H_\n+#define _RTE_GRO_TCP4_H_\n+\n+#define INVALID_ARRAY_INDEX 0xffffffffUL\n+#define GRO_TCP4_TBL_MAX_ITEM_NUM (UINT32_MAX - 1)\n+\n+/* criteria of mergeing packets */\n+struct tcp4_key {\n+\tstruct ether_addr eth_saddr;\n+\tstruct ether_addr eth_daddr;\n+\tuint32_t ip_src_addr;\n+\tuint32_t ip_dst_addr;\n+\n+\tuint32_t recv_ack;\t/**< acknowledgment sequence number. */\n+\tuint16_t src_port;\n+\tuint16_t dst_port;\n+};\n+\n+struct gro_tcp4_key {\n+\tstruct tcp4_key key;\n+\tuint32_t start_index;\t/**< the first packet index of the flow */\n+\tuint8_t is_valid;\n+};\n+\n+struct gro_tcp4_item {\n+\tstruct rte_mbuf *pkt;\t/**< packet address. */\n+\tstruct rte_mbuf *lastseg;\t/**< last segment of the packet */\n+\t/* the time when the packet in added into the table */\n+\tuint64_t start_time;\n+\tuint32_t next_pkt_idx;\t/**< next packet index. */\n+};\n+\n+/**\n+ * TCP/IPv4 reassembly table.\n+ */\n+struct gro_tcp4_tbl {\n+\tstruct gro_tcp4_item *items;\t/**< item array */\n+\tstruct gro_tcp4_key *keys;\t/**< key array */\n+\tuint32_t item_num;\t/**< current item number */\n+\tuint32_t key_num;\t/**< current key num */\n+\tuint32_t max_item_num;\t/**< item array size */\n+\tuint32_t max_key_num;\t/**< key array size */\n+};\n+\n+/**\n+ * This function creates a TCP/IPv4 reassembly table.\n+ *\n+ * @param socket_id\n+ *  socket index where the Ethernet port connects to.\n+ * @param max_flow_num\n+ *  the maximum number of flows in the TCP/IPv4 GRO table\n+ * @param max_item_per_flow\n+ *  the maximum packet number per flow.\n+ * @return\n+ *  if create successfully, return a pointer which points to the\n+ *  created TCP/IPv4 GRO table. Otherwise, return NULL.\n+ */\n+void *gro_tcp4_tbl_create(uint16_t socket_id,\n+\t\tuint16_t max_flow_num,\n+\t\tuint16_t max_item_per_flow);\n+\n+/**\n+ * This function destroys a TCP/IPv4 reassembly table.\n+ * @param tbl\n+ *  a pointer points to the TCP/IPv4 reassembly table.\n+ */\n+void gro_tcp4_tbl_destroy(void *tbl);\n+\n+/**\n+ * This function searches for a packet in the TCP/IPv4 reassembly table\n+ * to merge with the inputted one. To merge two packets is to chain them\n+ * together and update packet headers. Packets, whose SYN, FIN, RST, PSH\n+ * or URG bit is set, are returned immediately. Packets which only have\n+ * packet headers (i.e. without data) are also returned immediately.\n+ * Otherwise, the packet is either merged, or inserted into the table.\n+ * Besides, if there is no available space to insert the packet, this\n+ * function returns immediately too.\n+ *\n+ * This function assumes the inputted packet is with correct IPv4 and\n+ * TCP checksums. And if two packets are merged, it won't re-calculate\n+ * IPv4 and TCP checksums. Besides, if the inputted packet is IP\n+ * fragmented, it assumes the packet is complete (with TCP header).\n+ *\n+ * @param pkt\n+ *  packet to reassemble.\n+ * @param tbl\n+ *  a pointer that points to a TCP/IPv4 reassembly table.\n+ * @param max_packet_size\n+ *  max packet length after merged\n+ * @start_time\n+ *  the start time that the packet is inserted into the table\n+ * @return\n+ *  if the packet doesn't have data, or SYN, FIN, RST, PSH or URG bit is\n+ *  set, or there is no available space in the table to insert a new\n+ *  item or a new key, return a negative value. If the packet is merged\n+ *  successfully, return an positive value. If the packet is inserted\n+ *  into the table, return 0.\n+ */\n+int32_t\n+gro_tcp4_reassemble(struct rte_mbuf *pkt,\n+\t\tstruct gro_tcp4_tbl *tbl,\n+\t\tuint32_t max_packet_size,\n+\t\tuint64_t start_time);\n+\n+/**\n+ * This function flushes timeout packets in a TCP/IPv4 reassembly table\n+ * to applications, and without updating checksums for merged packets.\n+ * The max number of flushed timeout packets is the element number of\n+ * the array which is used to keep flushed packets.\n+ *\n+ * @param tbl\n+ *  a pointer that points to a TCP GRO table.\n+ * @param timeout_cycles\n+ *  the maximum time that packets can stay in the table.\n+ * @param out\n+ *  pointer array which is used to keep flushed packets.\n+ * @param nb_out\n+ *  the element number of out. It's also the max number of timeout\n+ *  packets that can be flushed finally.\n+ * @return\n+ *  the number of packets that are returned.\n+ */\n+uint16_t\n+gro_tcp4_tbl_timeout_flush(struct gro_tcp4_tbl *tbl,\n+\t\tuint64_t timeout_cycles,\n+\t\tstruct rte_mbuf **out,\n+\t\tuint16_t nb_out);\n+\n+/**\n+ * This function returns the number of the packets in a TCP/IPv4\n+ * reassembly table.\n+ *\n+ * @param tbl\n+ *  pointer points to a TCP/IPv4 reassembly table.\n+ * @return\n+ *  the number of packets in the table\n+ */\n+uint32_t\n+gro_tcp4_tbl_item_num(void *tbl);\n+#endif\n",
    "prefixes": [
        "dpdk-dev",
        "v10",
        "2/3"
    ]
}