}()
	<-ch
}

// blockMutexDeep produces a block profile event at stack depth n, including the
// caller.
func blockMutexDeep(t *testing.T, n int) {
	if n > 1 {
		blockMutexDeep(t, n-1)
		return
	}
	var mu sync.Mutex
	go func() {
		mu.Lock()
		mu.Lock()
	}()
	awaitBlockedGoroutine(t, "sync.Mutex.Lock", "blockMutexDeep", 1)
	mu.Unlock()
}