USER_RUNNABLE
u->flags |= USER_RUNNABLE;
if (!(u->flags & USER_RUNNABLE) &&
u->flags |= USER_RUNNABLE;
u->flags &= ~USER_RUNNABLE;
u->flags &= ~USER_RUNNABLE;
if (!(s->user->flags & USER_RUNNABLE)) {
s->user->flags |= USER_RUNNABLE;