code: func (kl *Kubelet) getPluginsDir() string {
  	return filepath.Join(kl.getRootDir(), config.DefaultKubeletPluginsDirName)
  }
docs: // getPluginsDir returns the full path to the directory under which plugin
  // directories are created.  Plugins can use these directories for data that
  // they need to persist.  Plugins should create subdirectories under this named
  // after their own names.