// notifications. The caller must eventually call notifyListWait to wait for
// such a notification, passing the returned ticket number.
//
//go:linkname notifyListAdd sync.runtime_notifyListAdd
func notifyListAdd(l *notifyList) uint32 {
	// This may be called concurrently, for example, when called from
	// sync.Cond.Wait while holding a RWMutex in read mode.
	return l.wait.Add(1) - 1
}