DPDK-实战之l3fwd-vf（虚拟化环境）

0x01 缘由

     年初，学习了l3fwd的例子，进行三层转发，现在学习下特定转发，这个在虚拟化设备中常见，也是加强对dpdk的熟悉。

0x02 介绍

     在虚拟化环境下的L3层转发应用是用DPDK处理数据包的一个简单例子。这个L3层转发应用充分发挥SR-IOV的特征。

     这个应用演示如何使用hash和LPM DPDK库去实现数据包转发。这个转发策略是基于输入包的信息。

     查询方法既有基于hash的也有基于LPM的，你如何选择在编译的时候决定。当所选择的查找方法是基于hash时，使用hash对象来模拟流分类阶段。 哈希对象与流表相关使用，以便在运行时将每个输入数据包映射到其流。

     哈希查询键由DiffServ 5元组表示，它由从输入数据包读取的以下字段组成：源IP地址，目标IP地址，协议，源端口和目标端口。 从识别的流表条目读取输入数据包的输出接口的ID。应用程序使用的一组流在初始化时静态配置并加载到散列中。 当选择的查找方法是基于LPM时，使用LPM对象来模拟IPv4分组的转发阶段。 LPM对象用作路由表，用于在运行时识别每个输入数据包的下一跳。

     LPM查找键由从输入数据包读取的目标IP地址字段表示。 输入数据包的输出接口的ID是LPM查询返回的下一跳。 应用程序使用的一组LPM规则在初始化时被静态配置并加载到LPM对象中。

0x03 运行环境

     运行参数样板：

      ./build/l3fwd-vf [EAL options] -- -p PORTMASK --config(port,queue,lcore)[,(port,queue,lcore)]

     参数解释：

          [EAL options] EAL选项已经在其他例子中已有说明。

          -p [端口掩码 -- 网卡掩码，在部署DPDK运行环境时绑定的网卡]： 十六进制表示

          --config: 哪个网口哪个队列绑定到哪个逻辑核

           –no-numa： 是否关闭对numa结构的识别

     运行实例：

      ./l3fwd-vf -l 1,2 -n 4 -- -p 0x3 --config="(0,0,1),(1,0,2)"

     -这个实例占用的逻辑核为1,2

     -启动1、2号网卡

     -端口映射关系为：

          0号网卡0号队列映射到1号逻辑核上；

          1号网卡0号队列映射到2号逻辑核上；

     运行效果如下（添加了一些提示信息）：

    LPM作为路由查询表：

Initializing port 0 ... Creating queues: nb_rxq=1 nb_txq=1...  Address:A0:36:9F:03:A8:CA, Allocated mbuf pool on socket 0LPM: Adding route 0x01010100 / 24 (0)LPM: Adding route 0x02010100 / 24 (1)LPM: Adding route 0x03010100 / 24 (2)LPM: Adding route 0x04010100 / 24 (3)LPM: Adding route 0x05010100 / 24 (4)LPM: Adding route 0x06010100 / 24 (5)LPM: Adding route 0x07010100 / 24 (6)LPM: Adding route 0x08010100 / 24 (7)txq=0,0,0 PMD: eth_igb_tx_queue_setup(): sw_ring=0x7ffc3814d2c0 hw_ring=0x7ffc3814f300 dma_addr=0x6734f300Initializing port 1 ... Creating queues: nb_rxq=1 nb_txq=1...  Address:A0:36:9F:03:A8:CB, txq=1,0,0 PMD: eth_igb_tx_queue_setup(): sw_ring=0x7ffc3813b040 hw_ring=0x7ffc3813d080 dma_addr=0x6733d080Initializing rx queues on lcore 1 ... rxq=0,0,0 PMD: eth_igb_rx_queue_setup(): sw_ring=0x7ffc3812aac0 hw_ring=0x7ffc3812af00 dma_addr=0x6732af00Initializing rx queues on lcore 2 ... rxq=1,0,0 PMD: eth_igb_rx_queue_setup(): sw_ring=0x7ffc3811a540 hw_ring=0x7ffc3811a980 dma_addr=0x6731a980PMD: eth_igb_start(): <<done: Port 0PMD: eth_igb_start(): <<done: Port 1L3FWD: entering main loop on lcore 2L3FWD:  -- lcoreid=2 portid=1 rxqueueid=0L3FWD: entering main loop on lcore 1L3FWD:  -- lcoreid=1 portid=0 rxqueueid=0

      Hash作为路由查询表：

Initializing port 0 ... Creating queues: nb_rxq=1 nb_txq=1...  Address:A0:36:9F:03:A8:CA, Allocated mbuf pool on socket 0Hash: Adding keyIP dst = 640a0001, IP src = c80a0001, port dst = 101, port src = 11, proto = 6Hash: Adding keyIP dst = 64140002, IP src = c8140002, port dst = 102, port src = 12, proto = 6Hash: Adding keyIP dst = 641e0003, IP src = c81e0003, port dst = 103, port src = 13, proto = 6Hash: Adding keyIP dst = 64280004, IP src = c8280004, port dst = 104, port src = 14, proto = 6txq=0,0,0 PMD: eth_igb_tx_queue_setup(): sw_ring=0x7fd48af7fcc0 hw_ring=0x7fd48af81d00 dma_addr=0x67381d00Initializing port 1 ... Creating queues: nb_rxq=1 nb_txq=1...  Address:A0:36:9F:03:A8:CB, txq=1,0,0 PMD: eth_igb_tx_queue_setup(): sw_ring=0x7fd48af6da40 hw_ring=0x7fd48af6fa80 dma_addr=0x6736fa80Initializing rx queues on lcore 1 ... rxq=0,0,0 PMD: eth_igb_rx_queue_setup(): sw_ring=0x7fd48af5d4c0 hw_ring=0x7fd48af5d900 dma_addr=0x6735d900Initializing rx queues on lcore 2 ... rxq=1,0,0 PMD: eth_igb_rx_queue_setup(): sw_ring=0x7fd48af4cf40 hw_ring=0x7fd48af4d380 dma_addr=0x6734d380PMD: eth_igb_start(): <<done: Port 0PMD: eth_igb_start(): <<done: Port 1L3FWD: entering main loop on lcore 2L3FWD:  -- lcoreid=2 portid=1 rxqueueid=0L3FWD: entering main loop on lcore 1L3FWD:  -- lcoreid=1 portid=0 rxqueueid=0

   模拟发包去查询（添加一些实际输出）：

          绑定两个网口0，1,连接到另一台服务器，另一台服务器抓包，分析数据包修改的情况，运行效果如下：

     

          数据包分析：

     

0x04 整体源码分析

#include <stdio.h>#include <stdlib.h>#include <stdint.h>#include <inttypes.h>#include <sys/types.h>#include <string.h>#include <sys/queue.h>#include <stdarg.h>#include <errno.h>#include <getopt.h>#include <signal.h>#include <rte_common.h>#include <rte_byteorder.h>#include <rte_log.h>#include <rte_memory.h>#include <rte_memcpy.h>#include <rte_memzone.h>#include <rte_eal.h>#include <rte_per_lcore.h>#include <rte_launch.h>#include <rte_atomic.h>#include <rte_spinlock.h>#include <rte_cycles.h>#include <rte_prefetch.h>#include <rte_lcore.h>#include <rte_per_lcore.h>#include <rte_branch_prediction.h>#include <rte_interrupts.h>#include <rte_pci.h>#include <rte_random.h>#include <rte_debug.h>#include <rte_ether.h>#include <rte_ethdev.h>#include <rte_ring.h>#include <rte_mempool.h>#include <rte_mbuf.h>#include <rte_ip.h>#include <rte_tcp.h>#include <rte_udp.h>#include <rte_string_fns.h>#define APP_LOOKUP_EXACT_MATCH          0     //精确匹配算法 #define APP_LOOKUP_LPM                  1     //最长匹配算法#define DO_RFC_1812_CHECKS                    //校验检查 如ip头的合法性//#define APP_LOOKUP_METHOD             APP_LOOKUP_EXACT_MATCH  //使用何种查询表#ifndef APP_LOOKUP_METHOD#define APP_LOOKUP_METHOD             APP_LOOKUP_LPM#endif/* 下面是一些相关头文件 */#if (APP_LOOKUP_METHOD == APP_LOOKUP_EXACT_MATCH)#include <rte_hash.h>#elif (APP_LOOKUP_METHOD == APP_LOOKUP_LPM)#include <rte_lpm.h>#else#error "APP_LOOKUP_METHOD set to incorrect value"#endif#define RTE_LOGTYPE_L3FWD RTE_LOGTYPE_USER1/* 内存池缓存大小 */#define MEMPOOL_CACHE_SIZE 256/* * 该表达式用于根据用户输入计算所需的mbufs数，考虑到rx和tx硬件环的内存，每lcore的缓存和每个端口的mtable . * RTE_MAX用于确保NB_MBUF不会低于最小值 8192。 */#define NB_MBUF RTE_MAX(\(nb_ports*nb_rx_queue*RTE_TEST_RX_DESC_DEFAULT +\nb_ports*nb_lcores*MAX_PKT_BURST +\nb_ports*n_tx_queue*RTE_TEST_TX_DESC_DEFAULT +\nb_lcores*MEMPOOL_CACHE_SIZE),\(unsigned)8192)/* *应优先设置RX和TX预取，主机和写回阈值以获得最佳性能。 请参阅网络控制器的数据表和支持DPDK文档， *了解如何设置这些参数的指导。 */#define RX_PTHRESH 8 /**< Default values of RX prefetch threshold reg. */#define RX_HTHRESH 8 /**< Default values of RX host threshold reg. */#define RX_WTHRESH 4 /**< Default values of RX write-back threshold reg. *//* *这些默认值经过优化，可与Intel（R）82599 10 GbE控制器和DPDK ixgbe PMD配合使用。 考虑为其他网络控 *制器和/或网络驱动程序使用其他值。 */#define TX_PTHRESH 36 /**< Default values of TX prefetch threshold reg. */#define TX_HTHRESH 0  /**< Default values of TX host threshold reg. */#define TX_WTHRESH 0  /**< Default values of TX write-back threshold reg. */#define MAX_PKT_BURST 32#define BURST_TX_DRAIN_US 100 /* TX drain every ~100us */#define NB_SOCKETS 8#define SOCKET0 0/* 在读取数据包时，配置预取数据包数。 */#define PREFETCH_OFFSET3/* * 可配置的RX / TX环形描述符数量。 */#define RTE_TEST_RX_DESC_DEFAULT 128#define RTE_TEST_TX_DESC_DEFAULT 512static uint16_t nb_rxd = RTE_TEST_RX_DESC_DEFAULT;static uint16_t nb_txd = RTE_TEST_TX_DESC_DEFAULT;/* 网口的地址 */static struct ether_addr ports_eth_addr[RTE_MAX_ETHPORTS];/* mask of enabled ports */static uint32_t enabled_port_mask = 0;static int numa_on = 1; /**< 默认启动numa特性 *//* mbuf表*/struct mbuf_table {uint16_t len;  //长度struct rte_mbuf *m_table[MAX_PKT_BURST];//对应的rte_mbuf结构指针数组。};/* 与该逻辑核关联的网口和队列id */struct lcore_rx_queue {uint8_t port_id;  //网口IDuint8_t queue_id; //接收队列ID} __rte_cache_aligned;#define MAX_RX_QUEUE_PER_LCORE 16  //每个逻辑核最多有16个接收队列#define MAX_TX_QUEUE_PER_PORT 1  //每个网口一个发送队列#define MAX_RX_QUEUE_PER_PORT 1  //每个网口一个接受队列#define MAX_LCORE_PARAMS 1024     //最多1024个lcore参数struct lcore_params {     uint8_t port_id;    //网口iduint8_t queue_id;   //队列iduint8_t lcore_id;   //逻辑核id} __rte_cache_aligned;static struct lcore_params lcore_params_array[MAX_LCORE_PARAMS]; //静态全局逻辑核参数//当未配置时使用默认值static struct lcore_params lcore_params_array_default[] = {  {0, 0, 2},{0, 1, 2},{0, 2, 2},{1, 0, 2},{1, 1, 2},{1, 2, 2},{2, 0, 2},{3, 0, 3},{3, 1, 3},};static struct lcore_params * lcore_params = lcore_params_array_default; //使用一个全局指针//配置多少个参数static uint16_t nb_lcore_params = sizeof(lcore_params_array_default) /sizeof(lcore_params_array_default[0]);//网口的一些属性设置，如模式，如巨型侦的处理。static struct rte_eth_conf port_conf = {.rxmode = {.mq_mode= ETH_MQ_RX_RSS,.max_rx_pkt_len = ETHER_MAX_LEN,.split_hdr_size = 0,.header_split   = 0, /**< Header Split disabled */.hw_ip_checksum = 1, /**< IP checksum offload enabled */.hw_vlan_filter = 0, /**< VLAN filtering disabled */.jumbo_frame    = 0, /**< Jumbo Frame Support disabled */.hw_strip_crc   = 0, /**< CRC stripped by hardware */},.rx_adv_conf = {.rss_conf = {.rss_key = NULL,.rss_hf = ETH_RSS_IP,},},.txmode = {.mq_mode = ETH_MQ_TX_NONE,},};//内存池指针，对应物理CPU颗数。static struct rte_mempool * pktmbuf_pool[NB_SOCKETS];//下面是用hash的方式进行精确匹配#if (APP_LOOKUP_METHOD == APP_LOOKUP_EXACT_MATCH)#ifdef RTE_MACHINE_CPUFLAG_SSE4_2#include <rte_hash_crc.h>#define DEFAULT_HASH_FUNC       rte_hash_crc#else#include <rte_jhash.h>#define DEFAULT_HASH_FUNC       rte_jhash#endif//五元组struct ipv4_5tuple {uint32_t ip_dst; //目的IP地址uint32_t ip_src; //源IP地址uint16_t port_dst; //目的端口uint16_t port_src; //源端口uint8_t proto;  //协议类型} __attribute__((__packed__));//三层转发路由struct l3fwd_route {struct ipv4_5tuple key; //五元组keyuint8_t if_out;  //出口网口};//配置hash 路由参数static struct l3fwd_route l3fwd_route_array[] = {{{IPv4(100,10,0,1), IPv4(200,10,0,1), 101, 11, IPPROTO_TCP}, 0},{{IPv4(100,20,0,2), IPv4(200,20,0,2), 102, 12, IPPROTO_TCP}, 1},{{IPv4(100,30,0,3), IPv4(200,30,0,3), 103, 13, IPPROTO_TCP}, 2},{{IPv4(100,40,0,4), IPv4(200,40,0,4), 104, 14, IPPROTO_TCP}, 3},};typedef struct rte_hash lookup_struct_t;  //rte hash结构static lookup_struct_t *l3fwd_lookup_struct[NB_SOCKETS]; //申请指针数组#define L3FWD_HASH_ENTRIES1024//hash 参数struct rte_hash_parameters l3fwd_hash_params = {.name = "l3fwd_hash_0",.entries = L3FWD_HASH_ENTRIES,.key_len = sizeof(struct ipv4_5tuple),.hash_func = DEFAULT_HASH_FUNC,.hash_func_init_val = 0,.socket_id = SOCKET0,};#define L3FWD_NUM_ROUTES \(sizeof(l3fwd_route_array) / sizeof(l3fwd_route_array[0]))static uint8_t l3fwd_out_if[L3FWD_HASH_ENTRIES] __rte_cache_aligned;#endif//LPM 相关结构和初始化#if (APP_LOOKUP_METHOD == APP_LOOKUP_LPM)//三层路由结构struct l3fwd_route {uint32_t ip;  //ipuint8_t  depth; //深度uint8_t  if_out; //出口};//相关参数static struct l3fwd_route l3fwd_route_array[] = {{IPv4(1,1,1,0), 24, 0},{IPv4(2,1,1,0), 24, 1},{IPv4(3,1,1,0), 24, 2},{IPv4(4,1,1,0), 24, 3},{IPv4(5,1,1,0), 24, 4},{IPv4(6,1,1,0), 24, 5},{IPv4(7,1,1,0), 24, 6},{IPv4(8,1,1,0), 24, 7},};//理由参数个数#define L3FWD_NUM_ROUTES \(sizeof(l3fwd_route_array) / sizeof(l3fwd_route_array[0]))//规则个数#define L3FWD_LPM_MAX_RULES     1024typedef struct rte_lpm lookup_struct_t;static lookup_struct_t *l3fwd_lookup_struct[NB_SOCKETS];#endif//逻辑核配置struct lcore_conf {uint16_t n_rx_queue; //接收队列个数struct lcore_rx_queue rx_queue_list[MAX_RX_QUEUE_PER_LCORE]; //接收队列配置数组uint16_t tx_queue_id; //发送队列idstruct mbuf_table tx_mbufs[RTE_MAX_ETHPORTS]; //数据包缓存lookup_struct_t * lookup_struct; //查询结构} __rte_cache_aligned;static struct lcore_conf lcore_conf[RTE_MAX_LCORE]; //逻辑核参数static rte_spinlock_t spinlock_conf[RTE_MAX_ETHPORTS] = {RTE_SPINLOCK_INITIALIZER}; //自旋锁，来保证对一个网口竞争访问；/* 在一个发送网口发送数据包 */static inline intsend_burst(struct lcore_conf *qconf, uint16_t n, uint8_t port){struct rte_mbuf **m_table; //包结构表int ret;uint16_t queueid;queueid = qconf->tx_queue_id;m_table = (struct rte_mbuf **)qconf->tx_mbufs[port].m_table;rte_spinlock_lock(&spinlock_conf[port]); //上锁（在这盘旋）ret = rte_eth_tx_burst(port, queueid, m_table, n); //发送数据rte_spinlock_unlock(&spinlock_conf[port]); //释放锁，其他线程可以访问if (unlikely(ret < n)) {do {rte_pktmbuf_free(m_table[ret]); //释放结构} while (++ret < n);}return 0;}/* 将一个包插入队列，当队列满时将数据发送。*/static inline intsend_single_packet(struct rte_mbuf *m, uint8_t port){uint32_t lcore_id;uint16_t len;struct lcore_conf *qconf;lcore_id = rte_lcore_id(); //获取当前线程处于哪个逻辑核上qconf = &lcore_conf[lcore_id]; //根据对应的逻辑核找对对应的配置len = qconf->tx_mbufs[port].len;  //此时发送队列中的包个数qconf->tx_mbufs[port].m_table[len] = m; //将对应的数据放到对应的位置len++;        //包长度加1/* 当队列数据包达到了MAX_PKT_BURST ，则立刻发送 */if (unlikely(len == MAX_PKT_BURST)) {send_burst(qconf, MAX_PKT_BURST, port); //发送对应的数据包len = 0; //长度置0}qconf->tx_mbufs[port].len = len; //这个网口的发送队列置0return 0;}#ifdef DO_RFC_1812_CHECKS//此处做相关校验。static inline intis_valid_ipv4_pkt(struct ipv4_hdr *pkt, uint32_t link_len){/* From http://www.rfc-editor.org/rfc/rfc1812.txt section 5.2.2 *//* * 1. The packet length reported by the Link Layer must be large * enough to hold the minimum length legal IP datagram (20 bytes). */if (link_len < sizeof(struct ipv4_hdr))return -1;/* 2. The IP checksum must be correct. *//* this is checked in H/W *//* * 3. The IP version number must be 4. If the version number is not 4 * then the packet may be another version of IP, such as IPng or * ST-II. */if (((pkt->version_ihl) >> 4) != 4)return -3;/* * 4. The IP header length field must be large enough to hold the * minimum length legal IP datagram (20 bytes = 5 words). */if ((pkt->version_ihl & 0xf) < 5)return -4;/* * 5. The IP total length field must be large enough to hold the IP * datagram header, whose length is specified in the IP header length * field. */if (rte_cpu_to_be_16(pkt->total_length) < sizeof(struct ipv4_hdr))return -5;return 0;}#endif#if (APP_LOOKUP_METHOD == APP_LOOKUP_EXACT_MATCH)static voidprint_key(struct ipv4_5tuple key){//打印5元组printf("IP dst = %08x, IP src = %08x, port dst = %d, port src = %d, proto = %d\n",       (unsigned)key.ip_dst, (unsigned)key.ip_src, key.port_dst, key.port_src, key.proto);}//得到转发网口static inline uint8_tget_dst_port(struct ipv4_hdr *ipv4_hdr,  uint8_t portid, lookup_struct_t * l3fwd_lookup_struct){struct ipv4_5tuple key; //五元组keystruct tcp_hdr *tcp;  //tcp 头部结构struct udp_hdr *udp;  //udp 头部结构int ret = 0;//将整数值从大端模式转化到cpu序列key.ip_dst = rte_be_to_cpu_32(ipv4_hdr->dst_addr);key.ip_src = rte_be_to_cpu_32(ipv4_hdr->src_addr);key.proto = ipv4_hdr->next_proto_id; //ip层下的协议号，如tcp/udpswitch (ipv4_hdr->next_proto_id) {case IPPROTO_TCP:tcp = (struct tcp_hdr *)((unsigned char *) ipv4_hdr +sizeof(struct ipv4_hdr));key.port_dst = rte_be_to_cpu_16(tcp->dst_port); //目的端口key.port_src = rte_be_to_cpu_16(tcp->src_port);  //源端口break;case IPPROTO_UDP:udp = (struct udp_hdr *)((unsigned char *) ipv4_hdr +sizeof(struct ipv4_hdr));key.port_dst = rte_be_to_cpu_16(udp->dst_port);key.port_src = rte_be_to_cpu_16(udp->src_port);break;default:key.port_dst = 0;key.port_src = 0;}/* 查找目的端口 */ret = rte_hash_lookup(l3fwd_lookup_struct, (const void *)&key);//找不到默认从输入队列出，找到就从l3fwd_out_if[ret]返回；return (uint8_t)((ret < 0)? portid : l3fwd_out_if[ret]);}#endif#if (APP_LOOKUP_METHOD == APP_LOOKUP_LPM)static inline uint8_tget_dst_port(struct ipv4_hdr *ipv4_hdr,  uint8_t portid, lookup_struct_t * l3fwd_lookup_struct){uint32_t next_hop;//将目的地址传入进行查询下一条信息。return (uint8_t) ((rte_lpm_lookup(l3fwd_lookup_struct,rte_be_to_cpu_32(ipv4_hdr->dst_addr), &next_hop) == 0)?next_hop : portid);}#endif//三层转发static inline voidl3fwd_simple_forward(struct rte_mbuf *m, uint8_t portid, lookup_struct_t * l3fwd_lookup_struct){struct ether_hdr *eth_hdr; //以太网头结构struct ipv4_hdr *ipv4_hdr; //IP头void *tmp;uint8_t dst_port;//找到以太网头偏移地址eth_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);  //找到IP头偏移地址 偏移了sizeof(struct ether_hdr)位ipv4_hdr = rte_pktmbuf_mtod_offset(m, struct ipv4_hdr *,   sizeof(struct ether_hdr));#ifdef DO_RFC_1812_CHECKS//做头部检查/* Check to make sure the packet is valid (RFC1812) */if (is_valid_ipv4_pkt(ipv4_hdr, m->pkt_len) < 0) {rte_pktmbuf_free(m);return;}#endif//查找路由dst_port = get_dst_port(ipv4_hdr, portid, l3fwd_lookup_struct);if (dst_port >= RTE_MAX_ETHPORTS || (enabled_port_mask & 1 << dst_port) == 0)dst_port = portid; //查出来的dst_port有问题，或者是未启动的port，则用默认的portprintf("forward to %d port\n", dst_port);/* 02:00:00:00:00:xx ，修改目的mac地址*/tmp = ð_hdr->d_addr.addr_bytes[0];*((uint64_t *)tmp) = 0x000000000002 + ((uint64_t)dst_port << 40);#ifdef DO_RFC_1812_CHECKS/* Update time to live and header checksum */--(ipv4_hdr->time_to_live); //更新TTL++(ipv4_hdr->hdr_checksum);#endif/* src addr 复制源地址 */ether_addr_copy(&ports_eth_addr[dst_port], ð_hdr->s_addr);send_single_packet(m, dst_port);}/* main processing loop */static intmain_loop(__attribute__((unused)) void *dummy){//每个逻辑核都会有一个线程处理struct rte_mbuf *pkts_burst[MAX_PKT_BURST]; //数据包发送缓存unsigned lcore_id;   uint64_t prev_tsc, diff_tsc, cur_tsc;int i, j, nb_rx;uint8_t portid, queueid;struct lcore_conf *qconf;const uint64_t drain_tsc = (rte_get_tsc_hz() + US_PER_S - 1) / US_PER_S * BURST_TX_DRAIN_US;prev_tsc = 0;lcore_id = rte_lcore_id(); //获取逻辑核IDqconf = &lcore_conf[lcore_id]; //逻辑核对应的配置，逻辑核可以找到自己处理那些端口，哪些队列等。if (qconf->n_rx_queue == 0) {//逻辑核为配置任何队列，说明没啥事干，退出RTE_LOG(INFO, L3FWD, "lcore %u has nothing to do\n", lcore_id);return 0;}RTE_LOG(INFO, L3FWD, "entering main loop on lcore %u\n", lcore_id);for (i = 0; i < qconf->n_rx_queue; i++) {portid = qconf->rx_queue_list[i].port_id; //对应的网卡queueid = qconf->rx_queue_list[i].queue_id;  //对应的接收队列idRTE_LOG(INFO, L3FWD, " -- lcoreid=%u portid=%hhu rxqueueid=%hhu\n", lcore_id,portid, queueid);}while (1) {//计时cur_tsc = rte_rdtsc();/* * 发送数据包 */diff_tsc = cur_tsc - prev_tsc;if (unlikely(diff_tsc > drain_tsc)) {/* * This could be optimized (use queueid instead of * portid), but it is not called so often */for (portid = 0; portid < RTE_MAX_ETHPORTS; portid++) {//每个网口就一个发送队列if (qconf->tx_mbufs[portid].len == 0)continue;//发送数据包send_burst(&lcore_conf[lcore_id],qconf->tx_mbufs[portid].len,portid);qconf->tx_mbufs[portid].len = 0;}prev_tsc = cur_tsc;}/* * 从RX queues 读取数据包 */for (i = 0; i < qconf->n_rx_queue; ++i) {portid = qconf->rx_queue_list[i].port_id; //端口queueid = qconf->rx_queue_list[i].queue_id; //队列idnb_rx = rte_eth_rx_burst(portid, queueid, pkts_burst, MAX_PKT_BURST);/* 第一次逾期数据包 */for (j = 0; j < PREFETCH_OFFSET && j < nb_rx; j++) {rte_prefetch0(rte_pktmbuf_mtod(pkts_burst[j], void *));}/* 预取并转发已经预取的数据包 */for (j = 0; j < (nb_rx - PREFETCH_OFFSET); j++) {rte_prefetch0(rte_pktmbuf_mtod(pkts_burst[j + PREFETCH_OFFSET], void *));l3fwd_simple_forward(pkts_burst[j], portid, qconf->lookup_struct);}/*  转发剩余的数据包 */for (; j < nb_rx; j++) {l3fwd_simple_forward(pkts_burst[j], portid, qconf->lookup_struct);}}}}//检查逻辑核相关参数static intcheck_lcore_params(void){uint8_t queue, lcore;uint16_t i;int socketid;for (i = 0; i < nb_lcore_params; ++i) {//队列是否在范围内queue = lcore_params[i].queue_id;if (queue >= MAX_RX_QUEUE_PER_PORT) {printf("invalid queue number: %hhu\n", queue);return -1;}//逻辑核是否在启动参数中指定lcore = lcore_params[i].lcore_id;if (!rte_lcore_is_enabled(lcore)) { printf("error: lcore %hhu is not enabled in lcore mask\n", lcore);return -1;}//numa结构if ((socketid = rte_lcore_to_socket_id(lcore) != 0) &&(numa_on == 0)) {printf("warning: lcore %hhu is on socket %d with numa off \n",lcore, socketid);}}return 0;}//检查网口配置static intcheck_port_config(const unsigned nb_ports){unsigned portid;uint16_t i;for (i = 0; i < nb_lcore_params; ++i) {//是否在运行参数中指定portid = lcore_params[i].port_id;if ((enabled_port_mask & (1 << portid)) == 0) {printf("port %u is not enabled in port mask\n", portid);return -1;}if (portid >= nb_ports) {printf("port %u is not present on the board\n", portid);return -1;}}return 0;}//得到网口的接收队列数static uint8_tget_port_n_rx_queues(const uint8_t port){int queue = -1;uint16_t i;for (i = 0; i < nb_lcore_params; ++i) {if (lcore_params[i].port_id == port && lcore_params[i].queue_id > queue)queue = lcore_params[i].queue_id;}return (uint8_t)(++queue);}//初始化接收队列逻辑核配置结构static intinit_lcore_rx_queues(void){uint16_t i, nb_rx_queue;uint8_t lcore;for (i = 0; i < nb_lcore_params; ++i) {lcore = lcore_params[i].lcore_id; //逻辑核IDnb_rx_queue = lcore_conf[lcore].n_rx_queue; //此逻辑核队列数if (nb_rx_queue >= MAX_RX_QUEUE_PER_LCORE) { //检查合法性printf("error: too many queues (%u) for lcore: %u\n",(unsigned)nb_rx_queue + 1, (unsigned)lcore);return -1;} else {lcore_conf[lcore].rx_queue_list[nb_rx_queue].port_id =lcore_params[i].port_id; //lcore_conf[lcore].rx_queue_list[nb_rx_queue].queue_id =lcore_params[i].queue_id;lcore_conf[lcore].n_rx_queue++;}}return 0;}/* display usage */static voidprint_usage(const char *prgname){printf ("%s [EAL options] -- -p PORTMASK""  [--config (port,queue,lcore)[,(port,queue,lcore]]\n""  -p PORTMASK: hexadecimal bitmask of ports to configure\n""  --config (port,queue,lcore): rx queues configuration\n""  --no-numa: optional, disable numa awareness\n",prgname);}/* 捕获从终端获取的信号，进行善后处理。*/static voidsignal_handler(int signum){uint8_t portid;uint8_t nb_ports = rte_eth_dev_count();/* When we receive a SIGINT signal */if (signum == SIGINT) {for (portid = 0; portid < nb_ports; portid++) {/* skip ports that are not enabled 检查哪些网卡启动 */if ((enabled_port_mask & (1 << portid)) == 0)continue;rte_eth_dev_close(portid); //关闭相关网卡}}rte_exit(EXIT_SUCCESS, "\n User forced exit\n");}//处理网口掩码static intparse_portmask(const char *portmask){char *end = NULL;unsigned long pm;/* parse hexadecimal string */pm = strtoul(portmask, &end, 16);/*strtoul()会将参数nptr字符串根据参数base来转换成无符号的长整型数。参数base范围从2至36，或0。参数base代表采用的进制方式，如base值为10则采用10进制，若base值为16则采用16进制数等。*/if ((portmask[0] == '\0') || (end == NULL) || (*end != '\0'))return -1;if (pm == 0)return -1;return pm;}//解析--config这个参数static intparse_config(const char *q_arg){char s[256];const char *p, *p0 = q_arg;char *end;enum fieldnames {FLD_PORT = 0,FLD_QUEUE,FLD_LCORE,_NUM_FLD};unsigned long int_fld[_NUM_FLD];char *str_fld[_NUM_FLD];int i;unsigned size;nb_lcore_params = 0;while ((p = strchr(p0,'(')) != NULL) {++p;if((p0 = strchr(p,')')) == NULL)return -1;size = p0 - p;if(size >= sizeof(s))return -1;snprintf(s, sizeof(s), "%.*s", size, p);if (rte_strsplit(s, sizeof(s), str_fld, _NUM_FLD, ',') != _NUM_FLD)return -1;for (i = 0; i < _NUM_FLD; i++){errno = 0;int_fld[i] = strtoul(str_fld[i], &end, 0);if (errno != 0 || end == str_fld[i] || int_fld[i] > 255)return -1;}if (nb_lcore_params >= MAX_LCORE_PARAMS) {printf("exceeded max number of lcore params: %hu\n",nb_lcore_params);return -1;}lcore_params_array[nb_lcore_params].port_id = (uint8_t)int_fld[FLD_PORT];lcore_params_array[nb_lcore_params].queue_id = (uint8_t)int_fld[FLD_QUEUE];lcore_params_array[nb_lcore_params].lcore_id = (uint8_t)int_fld[FLD_LCORE];++nb_lcore_params;}lcore_params = lcore_params_array;return 0;}/* Parse the argument given in the command line of the application */static intparse_args(int argc, char **argv){int opt, ret;char **argvopt;int option_index;char *prgname = argv[0];static struct option lgopts[] = {{"config", 1, 0, 0},{"no-numa", 0, 0, 0},{NULL, 0, 0, 0}};argvopt = argv;while ((opt = getopt_long(argc, argvopt, "p:",lgopts, &option_index)) != EOF) {switch (opt) {/* portmask */case 'p':enabled_port_mask = parse_portmask(optarg);if (enabled_port_mask == 0) {printf("invalid portmask\n");print_usage(prgname);return -1;}break;/* long options */case 0:if (!strcmp(lgopts[option_index].name, "config")) {ret = parse_config(optarg);if (ret) {printf("invalid config\n");print_usage(prgname);return -1;}}if (!strcmp(lgopts[option_index].name, "no-numa")) {printf("numa is disabled \n");numa_on = 0;}break;default:print_usage(prgname);return -1;}}if (optind >= 0)argv[optind-1] = prgname;ret = optind-1;optind = 0; /* reset getopt lib */return ret;}//打印mac地址static voidprint_ethaddr(const char *name, const struct ether_addr *eth_addr){char buf[ETHER_ADDR_FMT_SIZE];ether_format_addr(buf, ETHER_ADDR_FMT_SIZE, eth_addr);printf("%s%s", name, buf);}#if (APP_LOOKUP_METHOD == APP_LOOKUP_EXACT_MATCH)//构建hash表 static voidsetup_hash(int socketid){unsigned i;int ret;char s[64];/* create  hashes */snprintf(s, sizeof(s), "l3fwd_hash_%d", socketid);l3fwd_hash_params.name = s; //hash表名称l3fwd_hash_params.socket_id = socketid; //对应的物理cpu idl3fwd_lookup_struct[socketid] = rte_hash_create(&l3fwd_hash_params); //创建相关结构 if (l3fwd_lookup_struct[socketid] == NULL)rte_exit(EXIT_FAILURE, "Unable to create the l3fwd hash on ""socket %d\n", socketid);/* 根据配置添加key,计算hash值 */for (i = 0; i < L3FWD_NUM_ROUTES; i++) {ret = rte_hash_add_key (l3fwd_lookup_struct[socketid],(void *) &l3fwd_route_array[i].key);if (ret < 0) {rte_exit(EXIT_FAILURE, "Unable to add entry %u to the""l3fwd hash on socket %d\n", i, socketid);}l3fwd_out_if[ret] = l3fwd_route_array[i].if_out; //每个hash条目对应的输入网口printf("Hash: Adding key\n");print_key(l3fwd_route_array[i].key);}}#endif#if (APP_LOOKUP_METHOD == APP_LOOKUP_LPM)//最长匹配算法static voidsetup_lpm(int socketid){unsigned i;int ret;char s[64];struct rte_lpm_config lpm_ipv4_config;lpm_ipv4_config.max_rules = L3FWD_LPM_MAX_RULES;lpm_ipv4_config.number_tbl8s = 256;lpm_ipv4_config.flags = 0;/* create the LPM table */snprintf(s, sizeof(s), "L3FWD_LPM_%d", socketid);l3fwd_lookup_struct[socketid] =rte_lpm_create(s, socketid, &lpm_ipv4_config);if (l3fwd_lookup_struct[socketid] == NULL)rte_exit(EXIT_FAILURE, "Unable to create the l3fwd LPM table"" on socket %d\n", socketid);/* populate the LPM table */for (i = 0; i < L3FWD_NUM_ROUTES; i++) {ret = rte_lpm_add(l3fwd_lookup_struct[socketid],l3fwd_route_array[i].ip,l3fwd_route_array[i].depth,l3fwd_route_array[i].if_out);if (ret < 0) {rte_exit(EXIT_FAILURE, "Unable to add entry %u to the ""l3fwd LPM table on socket %d\n",i, socketid);}printf("LPM: Adding route 0x%08x / %d (%d)\n",(unsigned)l3fwd_route_array[i].ip,l3fwd_route_array[i].depth,l3fwd_route_array[i].if_out);}}#endif//初始化相关内存结构static intinit_mem(unsigned nb_mbuf){struct lcore_conf *qconf;int socketid;unsigned lcore_id;char s[64];for (lcore_id = 0; lcore_id < RTE_MAX_LCORE; lcore_id++) {if (rte_lcore_is_enabled(lcore_id) == 0)continue;//numa结构if (numa_on)socketid = rte_lcore_to_socket_id(lcore_id);elsesocketid = 0;if (socketid >= NB_SOCKETS) {rte_exit(EXIT_FAILURE, "Socket %d of lcore %u is out of range %d\n",socketid, lcore_id, NB_SOCKETS);}if (pktmbuf_pool[socketid] == NULL) {//创建内存池snprintf(s, sizeof(s), "mbuf_pool_%d", socketid);pktmbuf_pool[socketid] = rte_pktmbuf_pool_create(s,nb_mbuf, MEMPOOL_CACHE_SIZE, 0,RTE_MBUF_DEFAULT_BUF_SIZE, socketid);if (pktmbuf_pool[socketid] == NULL)rte_exit(EXIT_FAILURE, "Cannot init mbuf pool on socket %d\n", socketid);elseprintf("Allocated mbuf pool on socket %d\n", socketid);#if (APP_LOOKUP_METHOD == APP_LOOKUP_LPM)setup_lpm(socketid);#elsesetup_hash(socketid);#endif}qconf = &lcore_conf[lcore_id];qconf->lookup_struct = l3fwd_lookup_struct[socketid];}return 0;}intmain(int argc, char **argv){struct lcore_conf *qconf;struct rte_eth_dev_info dev_info;struct rte_eth_txconf *txconf;int ret;unsigned nb_ports;uint16_t queueid;unsigned lcore_id;uint32_t nb_lcores;uint16_t n_tx_queue;uint8_t portid, nb_rx_queue, queue, socketid;//处理信号signal(SIGINT, signal_handler);/* init EAL */ret = rte_eal_init(argc, argv);if (ret < 0)rte_exit(EXIT_FAILURE, "Invalid EAL parameters\n");argc -= ret;argv += ret;/* parse application arguments (after the EAL ones) */ret = parse_args(argc, argv);if (ret < 0)rte_exit(EXIT_FAILURE, "Invalid L3FWD-VF parameters\n");if (check_lcore_params() < 0)rte_exit(EXIT_FAILURE, "check_lcore_params failed\n");ret = init_lcore_rx_queues();if (ret < 0)rte_exit(EXIT_FAILURE, "init_lcore_rx_queues failed\n");nb_ports = rte_eth_dev_count();if (nb_ports > RTE_MAX_ETHPORTS)nb_ports = RTE_MAX_ETHPORTS;if (check_port_config(nb_ports) < 0)rte_exit(EXIT_FAILURE, "check_port_config failed\n");nb_lcores = rte_lcore_count();/* initialize all ports */for (portid = 0; portid < nb_ports; portid++) {/* skip ports that are not enabled */if ((enabled_port_mask & (1 << portid)) == 0) {printf("\nSkipping disabled port %d\n", portid);continue;}/* init port */printf("Initializing port %d ... ", portid );fflush(stdout);/* must always equal(=1) */nb_rx_queue = get_port_n_rx_queues(portid);n_tx_queue = MAX_TX_QUEUE_PER_PORT;printf("Creating queues: nb_rxq=%d nb_txq=%u... ",nb_rx_queue, (unsigned)1 );//队列配置ret = rte_eth_dev_configure(portid, nb_rx_queue, n_tx_queue, &port_conf);if (ret < 0)rte_exit(EXIT_FAILURE, "Cannot configure device: err=%d, port=%d\n",ret, portid);rte_eth_macaddr_get(portid, &ports_eth_addr[portid]);print_ethaddr(" Address:", &ports_eth_addr[portid]);printf(", ");ret = init_mem(NB_MBUF);if (ret < 0)rte_exit(EXIT_FAILURE, "init_mem failed\n");/* init one TX queue */socketid = (uint8_t)rte_lcore_to_socket_id(rte_get_master_lcore());printf("txq=%d,%d,%d ", portid, 0, socketid);fflush(stdout);rte_eth_dev_info_get(portid, &dev_info);txconf = &dev_info.default_txconf;if (port_conf.rxmode.jumbo_frame)txconf->txq_flags = 0;//发送队列配置ret = rte_eth_tx_queue_setup(portid, 0, nb_txd, socketid, txconf);if (ret < 0)rte_exit(EXIT_FAILURE, "rte_eth_tx_queue_setup: err=%d, ""port=%d\n", ret, portid);printf("\n");}for (lcore_id = 0; lcore_id < RTE_MAX_LCORE; lcore_id++) {if (rte_lcore_is_enabled(lcore_id) == 0)continue;qconf = &lcore_conf[lcore_id];qconf->tx_queue_id = 0;printf("\nInitializing rx queues on lcore %u ... ", lcore_id );fflush(stdout);/* init RX queues */for(queue = 0; queue < qconf->n_rx_queue; ++queue) {portid = qconf->rx_queue_list[queue].port_id;queueid = qconf->rx_queue_list[queue].queue_id;if (numa_on)socketid = (uint8_t)rte_lcore_to_socket_id(lcore_id);elsesocketid = 0;printf("rxq=%d,%d,%d ", portid, queueid, socketid);fflush(stdout);//接收队列初始化ret = rte_eth_rx_queue_setup(portid, queueid, nb_rxd,socketid, NULL,pktmbuf_pool[socketid]);if (ret < 0)rte_exit(EXIT_FAILURE, "rte_eth_rx_queue_setup: err=%d,""port=%d\n", ret, portid);}}printf("\n");/* start ports */for (portid = 0; portid < nb_ports; portid++) {if ((enabled_port_mask & (1 << portid)) == 0) {continue;}/* Start device，开启设备 */ret = rte_eth_dev_start(portid);if (ret < 0)rte_exit(EXIT_FAILURE, "rte_eth_dev_start: err=%d, port=%d\n",ret, portid);printf("done: Port %d\n", portid);}/* launch per-lcore init on every lcore */rte_eal_mp_remote_launch(main_loop, NULL, CALL_MASTER);RTE_LCORE_FOREACH_SLAVE(lcore_id) {if (rte_eal_wait_lcore(lcore_id) < 0)return -1;}return 0;}

0x05 总结

     遇到一个问题，发现这个程序无法处理TCP的数据包，看后期慢慢熟悉能否解决这个问题。