TSF_BOUND
(td_get_sched(td)->ts_flags & TSF_BOUND) != 0,
if (ts->ts_flags & TSF_BOUND)
ts->ts_flags |= TSF_BOUND;
if ((ts->ts_flags & TSF_BOUND) == 0)
ts->ts_flags &= ~TSF_BOUND;
return (td_get_sched(td)->ts_flags & TSF_BOUND);