umem_walk_fini
bufctl_walk_init, umem_walk_step, umem_walk_fini },
freectl_walk_init, umem_walk_step, umem_walk_fini },
freemem_walk_init, umem_walk_step, umem_walk_fini },
umem_walk_init, umem_walk_step, umem_walk_fini },
w.walk_fini = umem_walk_fini;
extern void umem_walk_fini(mdb_walk_state_t *);