+/**
+ * Update link carrier state for KNI port.
+ *
+ * Update the linkup/linkdown state of a KNI interface in the kernel.
+ *
+ * @param kni
+ * pointer to struct rte_kni.
+ * @param linkup
+ * New link state:
+ * 0 for linkdown.
+ * > 0 for linkup.
+ *
+ * @return
+ * On failure: -1
+ * Previous link state == linkdown: 0
+ * Previous link state == linkup: 1
+ */
+int __rte_experimental
+rte_kni_update_link(struct rte_kni *kni, unsigned int linkup);
+