sleepq_type
slptype = sleepq_type(wchan);
if (!TD_ON_SLEEPQ(td) || sleepq_type(td->td_wchan) != SLEEPQ_LK ||
if (!TD_ON_SLEEPQ(td) || sleepq_type(td->td_wchan) != SLEEPQ_SX ||
int sleepq_type(const void *wchan);