Function if_ref

freebsd/net/if.c:738–744

* Interfaces to keep an ifnet type-stable despite the possibility of the * driver calling if_free(). If there are additional references, we defer * freeing the underlying data structure. */

 * freeing the underlying data structure.
 */
void
if_ref(struct ifnet *ifp)
{

	/* We don't assert the ifnet list lock here, but arguably should. */
	refcount_acquire(&ifp->if_refcount);
}

void
if_rele(struct ifnet *ifp)