cond_waiters_user
cvp->cond_waiters_user = 1;
cvp->cond_waiters_user = dequeue_self(qp);
if (!cvp->cond_waiters_user) /* no one sleeping at user-level */
cvp->cond_waiters_user = more;
if (!cvp->cond_waiters_user) /* no one sleeping at user-level */
cvp->cond_waiters_user = 0;
(generic_so.condition.cond_waiters_user |