Function rte_eth_dev_callback_register

dpdk/lib/ethdev/rte_ethdev.c:5420–5487

}

int
rte_eth_dev_callback_register(uint16_t port_id,
			enum rte_eth_event_type event,
			rte_eth_dev_cb_fn cb_fn, void *cb_arg)
{
	struct rte_eth_dev *dev;
	struct rte_eth_dev_callback *user_cb;
	uint16_t next_port;
	uint16_t last_port;

	if (cb_fn == NULL) {
		RTE_ETHDEV_LOG(ERR,
			"Cannot register ethdev port %u callback from NULL\n",
			port_id);
		return -EINVAL;
	}

	if (!rte_eth_dev_is_valid_port(port_id) && port_id != RTE_ETH_ALL) {
		RTE_ETHDEV_LOG(ERR, "Invalid port_id=%d\n", port_id);
		return -EINVAL;
	}

	if (port_id == RTE_ETH_ALL) {
		next_port = 0;
		last_port = RTE_MAX_ETHPORTS - 1;
	} else {
		next_port = last_port = port_id;
	}

	rte_spinlock_lock(&eth_dev_cb_lock);

	do {
		dev = &rte_eth_devices[next_port];

		TAILQ_FOREACH(user_cb, &(dev->link_intr_cbs), next) {
			if (user_cb->cb_fn == cb_fn &&
				user_cb->cb_arg == cb_arg &&
				user_cb->event == event) {
				break;
			}
		}

		/* create a new callback. */
		if (user_cb == NULL) {
			user_cb = rte_zmalloc("INTR_USER_CALLBACK",
				sizeof(struct rte_eth_dev_callback), 0);
			if (user_cb != NULL) {
				user_cb->cb_fn = cb_fn;
				user_cb->cb_arg = cb_arg;
				user_cb->event = event;
				TAILQ_INSERT_TAIL(&(dev->link_intr_cbs),
						  user_cb, next);
			} else {
				rte_spinlock_unlock(&eth_dev_cb_lock);
				rte_eth_dev_callback_unregister(port_id, event,
								cb_fn, cb_arg);
				return -ENOMEM;
			}