code: func (kl *Kubelet) getPluginsRegistrationDir() string {
  	return filepath.Join(kl.getRootDir(), config.DefaultKubeletPluginsRegistrationDirName)
  }
docs: // getPluginsRegistrationDir returns the full path to the directory under which
  // plugins socket should be placed to be registered.
  // More information is available about plugin registration in the pluginwatcher
  // module