+/**
+ * Add a callback to be called on packet RX on a given port and queue.
+ *
+ * This API configures a function to be called for each burst of
+ * packets received on a given NIC port queue. The return value is a pointer
+ * that can be used to later remove the callback using
+ * rte_eth_remove_rx_callback().
+ *
+ * @param port_id
+ * The port identifier of the Ethernet device.
+ * @param queue_id
+ * The queue on the Ethernet device on which the callback is to be added.
+ * @param fn
+ * The callback function
+ * @param user_param
+ * A generic pointer parameter which will be passed to each invocation of the
+ * callback function on this port and queue.
+ *
+ * @return
+ * NULL on error.
+ * On success, a pointer value which can later be used to remove the callback.
+ */
+void *rte_eth_add_rx_callback(uint8_t port_id, uint16_t queue_id,
+ rte_rx_callback_fn fn, void *user_param);
+
+/**
+ * Add a callback to be called on packet TX on a given port and queue.
+ *
+ * This API configures a function to be called for each burst of
+ * packets sent on a given NIC port queue. The return value is a pointer
+ * that can be used to later remove the callback using
+ * rte_eth_remove_tx_callback().
+ *
+ * @param port_id
+ * The port identifier of the Ethernet device.
+ * @param queue_id
+ * The queue on the Ethernet device on which the callback is to be added.
+ * @param fn
+ * The callback function
+ * @param user_param
+ * A generic pointer parameter which will be passed to each invocation of the
+ * callback function on this port and queue.
+ *
+ * @return
+ * NULL on error.
+ * On success, a pointer value which can later be used to remove the callback.
+ */
+void *rte_eth_add_tx_callback(uint8_t port_id, uint16_t queue_id,
+ rte_tx_callback_fn fn, void *user_param);
+
+/**
+ * Remove an RX packet callback from a given port and queue.
+ *
+ * This function is used to removed callbacks that were added to a NIC port
+ * queue using rte_eth_add_rx_callback().
+ *
+ * Note: the callback is removed from the callback list but it isn't freed
+ * since the it may still be in use. The memory for the callback can be
+ * subsequently freed back by the application by calling rte_free():
+ *
+ * - Immediately - if the port is stopped, or the user knows that no
+ * callbacks are in flight e.g. if called from the thread doing RX/TX
+ * on that queue.
+ *
+ * - After a short delay - where the delay is sufficient to allow any
+ * in-flight callbacks to complete.
+ *
+ * @param port_id
+ * The port identifier of the Ethernet device.
+ * @param queue_id
+ * The queue on the Ethernet device from which the callback is to be removed.
+ * @param user_cb
+ * User supplied callback created via rte_eth_add_rx_callback().
+ *
+ * @return
+ * - 0: Success. Callback was removed.
+ * - -ENOTSUP: Callback support is not available.
+ * - -EINVAL: The port_id or the queue_id is out of range, or the callback
+ * is NULL or not found for the port/queue.
+ */
+int rte_eth_remove_rx_callback(uint8_t port_id, uint16_t queue_id,
+ struct rte_eth_rxtx_callback *user_cb);
+
+/**
+ * Remove a TX packet callback from a given port and queue.
+ *
+ * This function is used to removed callbacks that were added to a NIC port
+ * queue using rte_eth_add_tx_callback().
+ *
+ * Note: the callback is removed from the callback list but it isn't freed
+ * since the it may still be in use. The memory for the callback can be
+ * subsequently freed back by the application by calling rte_free():
+ *
+ * - Immediately - if the port is stopped, or the user knows that no
+ * callbacks are in flight e.g. if called from the thread doing RX/TX
+ * on that queue.
+ *
+ * - After a short delay - where the delay is sufficient to allow any
+ * in-flight callbacks to complete.
+ *
+ * @param port_id
+ * The port identifier of the Ethernet device.
+ * @param queue_id
+ * The queue on the Ethernet device from which the callback is to be removed.
+ * @param user_cb
+ * User supplied callback created via rte_eth_add_tx_callback().
+ *
+ * @return
+ * - 0: Success. Callback was removed.
+ * - -ENOTSUP: Callback support is not available.
+ * - -EINVAL: The port_id or the queue_id is out of range, or the callback
+ * is NULL or not found for the port/queue.
+ */
+int rte_eth_remove_tx_callback(uint8_t port_id, uint16_t queue_id,
+ struct rte_eth_rxtx_callback *user_cb);
+