code: func (kubemarkController *KubemarkController) WaitForCacheSync(stopCh chan struct{}) bool {
  	return controller.WaitForCacheSync("kubemark", stopCh,
  		kubemarkController.externalCluster.rcSynced,
  		kubemarkController.externalCluster.podSynced,
  		kubemarkController.kubemarkCluster.nodeSynced)
  }
docs: // WaitForCacheSync waits until all caches in the controller are populated.