turnstile_wait
turnstile_wait(ts, NULL, TS_SHARED_QUEUE);
turnstile_wait(ts, owner, TS_EXCLUSIVE_QUEUE);
turnstile_wait(ts, prio->rmp_thread,
turnstile_wait(ts, owner, TS_EXCLUSIVE_QUEUE);
turnstile_wait(ts, owner, TS_SHARED_QUEUE);
turnstile_wait(ts, owner,
void turnstile_wait(struct turnstile *, struct thread *, int);