dpdk事件通知机制，代码编写示例-DPDK中文网

下面是一个简单的DPDK事件通知机制代码示例：

#include <rte_eventdev.h>
#include <rte_event_eth_rx_adapter.h>

// 初始化Event Device
static int eventdev_init(void)
{
    // 获取第一个Event设备编号
    uint8_t eventdev_id = rte_event_dev_get_dev_id("event");
    if (eventdev_id == RTE_EVENT_DEV_ID_INVALID) {
        printf("Failed to get Event device\n");
        return -1;
    }

    // 初始化Event设备
    struct rte_event_dev_config config = {
        .nb_queues = 1,
        .nb_ports = 1,
        .event_dev_cfg = RTE_EVENT_DEV_CFG_PER_DEQUEUE_TIMEOUT_VAL_MS(100),
    };
    int ret = rte_event_dev_configure(eventdev_id, &config);
    if (ret < 0) {
        printf("Failed to configure Event device\n");
        return -1;
    }

    // 设置Event队列属性
    struct rte_event_queue_conf qconf;
    memset(&qconf, 0, sizeof(qconf));
    qconf.nb_atomic_flows = 1024;
    qconf.event_queue_cfg =
            RTE_EVENT_QUEUE_CFG_ALL_TYPES | RTE_EVENT_QUEUE_CFG_SINGLE_LINK;

   // 创建Event队列和端口并绑定在一起
   const uint8_t queue_id = 0;
   const uint8_t port_id = 0;
   ret = rte_event_port_link(eventdev_id, port_id, &queue_id, NULL, 1);
   if (ret != 1) {
       printf("Failed to link port and queue\n");
       return -1;
   }

   // 启用事件轮询模式，并设置处理函数
   ret = rte_event_dev_start(eventdev_id);
   if (ret < 0) {
       printf("Failed to start Event device\n");
       return -1;
   }

   // 注册感兴趣的事件类型
   const uint8_t event_type = RTE_EVENT_TYPE_ETH_RX_ADAPTER;
   ret = rte_event_eth_rx_adapter_queue_add(port_id, queue_id, event_type);
   if (ret < 0) {
        printf("Failed to register event type\n");
        return -1;
   }

   // 设置Event回调函数
   struct rte_event_callback cb_func = {
        .ev = NULL,
        .cb_fn = event_handler,
        .priority = RTE_EVENT_DEV_CALLBACK_PRIORITY_NORMAL,
    };
    ret = rte_event_dev_callback_register(eventdev_id, 0, &cb_func);
    if (ret != 0) {
        printf("Failed to register callback function\n");
        return -1;
    }

    return 0;
}

// Event回调函数
static void event_handler(struct rte_event *event, void *arg)
{
    // 处理事件数据包
}

int main(int argc, char **argv)
{
    // 初始化DPDK
    int ret = rte_eal_init(argc, argv);
    if (ret < 0) {
        printf("Failed to initialize DPDK\n");
        return -1;
    }

    // 初始化Event设备
    ret = eventdev_init();
    if (ret < 0) {
         printf("Failed to initialize Event device\n");
         return -1;
     }

     // 运行主循环处理程序
     while (!quit_signal) {
         rte_eal_mp_wait_lcore();
     }

     // 关闭Event设备并退出程序
     rte_event_dev_stop(eventdev_id);
     rte_eal_cleanup();

     return 0;
}

这段代码展示了如何使用DPDK的Event库来实现事件通知机制。在初始化Event设备时，我们需要配置Event队列和端口，并注册感兴趣的事件类型。然后通过设置回调函数来处理收到的事件数据包。最后，在主循环中等待事件发生并进行处理。