if v == mutex_unlocked {
		throw("unlock of unlocked lock")
	}
	if v == mutex_sleeping {
		futexwakeup(key32(&l.key), 1)
	}

	gp := getg()
	gp.m.mLockProfile.recordUnlock(l)
	gp.m.locks--
	if gp.m.locks < 0 {
		throw("runtime·unlock: lock count")
	}
	if gp.m.locks == 0 && gp.preempt { // restore the preemption request in case we've cleared it in newstack

			mp = muintptr(v &^ locked).ptr()
			if atomic.Casuintptr(&l.key, v, uintptr(mp.nextwaitm)) {
				// Dequeued an M.  Wake it.
				semawakeup(mp)
				break
			}
		}
	}
	gp.m.mLockProfile.recordUnlock(l)
	gp.m.locks--
	if gp.m.locks < 0 {
		throw("runtime·unlock: lock count")
	}
	if gp.m.locks == 0 && gp.preempt { // restore the preemption request in case we've cleared it in newstack