V_dyn_expire_lock
mtx_init(&V_dyn_expire_lock, "IPFW expired states list", NULL, MTX_DEF)
#define DYN_EXPIRED_LOCK_DESTROY() mtx_destroy(&V_dyn_expire_lock)
#define DYN_EXPIRED_LOCK() mtx_lock(&V_dyn_expire_lock)
#define DYN_EXPIRED_UNLOCK() mtx_unlock(&V_dyn_expire_lock)