func (m *rwmutexWriteRead) Unlock2() { m.mu.RUnlock() }

// generateMutexWaitTime causes a couple of goroutines
// to block a whole bunch of times on a sync.Mutex, returning
// the minimum amount of time that should be visible in the
// /sync/mutex-wait:seconds metric.
func generateMutexWaitTime(mu locker2) time.Duration {
	// Set up the runtime to always track casgstatus transitions for metrics.