以下是一个完整的DPDK实现从rx队列中接收数据包,并hash负载均衡到各个无锁队列rte_ring_ready中的代码,其中包括了初始化DPDK和创建无锁队列的代码:
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <inttypes.h>
#include <string.h>
#include <stdbool.h>
#include <rte_common.h>
#include <rte_eal.h>
#include <rte_ethdev.h>
#include <rte_cycles.h>
#include <rte_lcore.h>
#include <rte_mbuf.h>
#include <rte_ring.h>
#define NUM_RX_QUEUES 4
#define NUM_TX_QUEUES 4
#define RX_RING_SIZE 1024
#define TX_RING_SIZE 1024
#define NUM_READY_RINGS 8
uint16_t port_id = 0;
struct rte_ring *rte_ring_ready[NUM_READY_RINGS];
// 计算哈希值
static inline uint32_t calculate_hash(struct rte_mbuf *pkt) {
/* TODO: 根据具体应用场景自定义计算哈希值的函数 */
return pkt->hash.rss % NUM_READY_RINGS;
}
// 初始化DPDK
int dpdk_init() {
int ret;
char **argv;
int argc;
const char *progname = "my_program";
argc = 3;
argv = (char **)malloc(sizeof(char *) * argc);
argv[0] = strdup(progname);
argv[1] = "--no-pci";
argv[2] = "-n 4"; // 假设使用4个核心运行程序
ret = rte_eal_init(argc, argv);
if (ret < 0) {
rte_panic("Cannot init EAL\n");
return -1;
}
free(argv);
argc -= ret;
argv += ret;
port_id = rte_eth_find_next_owned_by(0, RTE_ETH_DEV_NO_OWNER);
if (port_id == RTE_MAX_ETHPORTS) {
printf("No Ethernet ports - bye\n");
return -1;
}
struct rte_eth_conf port_conf = {
.rxmode = {
.split_hdr_size = 0,
},
.txmode = {
.mq_mode = ETH_MQ_TX_NONE,
},
};
uint16_t nb_rxd = RX_RING_SIZE;
uint16_t nb_txd = TX_RING_SIZE;
/* Configuring Ethernet device */
ret = rte_eth_dev_configure(port_id, NUM_RX_QUEUES, NUM_TX_QUEUES, &port_conf);
if (ret < 0)
rte_exit(EXIT_FAILURE, "Cannot configure device: err=%d, port=%u\n", ret, port_id);
for (int i = 0; i < NUM_RX_QUEUES; i++) {
/* Configure the Ethernet device RX queue */
ret = rte_eth_rx_queue_setup(port_id, i, nb_rxd, rte_eth_dev_socket_id(port_id), NULL, rte_pktmbuf_pool_create("RX_POOL", nb_rxd * rte_eth_dev_count(), 32, 0, RTE_MBUF_DEFAULT_BUF_SIZE, rte_socket_id()));
if (ret < 0)
rte_exit(EXIT_FAILURE, "Cannot setup device RX queue: err=%d, port=%u\n", ret, port_id);
/* Configure the Ethernet device TX queue */
ret = rte_eth_tx_queue_setup(port_id, i, nb_txd, rte_eth_dev_socket_id(port_id), NULL);
if (ret < 0)
rte_exit(EXIT_FAILURE, "Cannot setup device TX queue: err=%d, port=%u\n", ret, port_id);
}
/* Start the Ethernet port */
ret = rte_eth_dev_start(port_id);
if (ret < 0)
rte_exit(EXIT_FAILURE, "Cannot start device: err=%d, port=%u\n", ret, port_id);
printf("DPDK initialized successfully!\n");
return 0;
}
// 初始化无锁队列
int init_ring() {
for (int i = 0; i < NUM_READY_RINGS; i++) {
char ring_name[32];
sprintf(ring_name, "RING_READY%d", i);
rte_ring_ready[i] = rte_ring_create(ring_name, RX_RING_SIZE, SOCKET_ID_ANY, RING_F_SP_ENQ | RING_F_SC_DEQ);
if (rte_ring_ready[i] == NULL) {
printf("Failed to create rte_ring_ready[%d]\n", i);
return -1;
}
}
return 0;
}
// 接收数据包并hash负载均衡到各个无锁队列中
void receive_packets(uint16_t queue_id) {
struct rte_mbuf *packet;
while (1) {
int nb_rx = rte_eth_rx_burst(port_id, queue_id, &packet, 1);
if (nb_rx == 0) {
continue;
}
uint32_t hash = calculate_hash(packet); // 计算哈希值
uint32_t ring_idx = hash % NUM_READY_RINGS; // 根据哈希值决定放入哪个无锁队列
rte_ring_enqueue(rte_ring_ready[ring_idx], packet); // 放入对应的无锁队列
}
}
int main(int argc, char *argv[]) {
int ret;
ret = dpdk_init(); // 初始化DPDK
if (ret < 0) {
return -1;
}
ret = init_ring(); // 初始化无锁队列
if (ret < 0) {
return -1;
}
int nb_lcores = rte_lcore_count();
for (int i = 0; i < nb_lcores; i++) {
if (rte_lcore_is_enabled(i)) {
rte_eal_remote_launch((lcore_function_t *)receive_packets, (void *)(intptr_t)i, i);
}
}
rte_eal_mp_wait_lcore();
rte_eal_cleanup();
return 0;
}
以上代码中,通过使用rte_eth_rx_burst()函数从rx队列中批量接收数据包,并判断是否成功接收到数据包。如果接收到了数据包,则计算该数据包的哈希值,并根据哈希值选择存放在哪个无锁队列中,最后将数据包放入该无锁队列中。
实现该功能,需要在DPDK应用程序的初始化过程中创建无锁队列rte_ring_ready,并分配对应的内存空间。