code: func (i *Instance) wakeOne() {
  	i.waitersByPriority.Iter(func(key interface{}) bool {
  		value := i.waitersByPriority.Get(key).(entryHandleSet)
  		for eh := range value {
  			i.wakeEntry(eh.e)
  			break
  		}
  		return false
  	})
  }
docs: // Wakes the highest priority waiter.