kubelet/volumemanager: simplify GetVolumesInUse

remove the map[v1.UniqueVolumeName]bool allocation
and also accelerate this func.

Author: huww98

pkg/kubelet/volumemanager/volume_manager.go

@@ -351,27 +351,21 @@ func (vm *volumeManager) GetVolumesInUse() []v1.UniqueVolumeName {
 	desiredVolumes := vm.desiredStateOfWorld.GetVolumesToMount()
 	allAttachedVolumes := vm.actualStateOfWorld.GetAttachedVolumes()
 	volumesToReportInUse := make([]v1.UniqueVolumeName, 0, len(desiredVolumes)+len(allAttachedVolumes))
-	desiredVolumesMap := make(map[v1.UniqueVolumeName]bool, len(desiredVolumes)+len(allAttachedVolumes))
 
 	for _, volume := range desiredVolumes {
 		if volume.PluginIsAttachable {
-			if _, exists := desiredVolumesMap[volume.VolumeName]; !exists {
-				desiredVolumesMap[volume.VolumeName] = true
-				volumesToReportInUse = append(volumesToReportInUse, volume.VolumeName)
-			}
+			volumesToReportInUse = append(volumesToReportInUse, volume.VolumeName)
 		}
 	}
 
 	for _, volume := range allAttachedVolumes {
 		if volume.PluginIsAttachable {
-			if _, exists := desiredVolumesMap[volume.VolumeName]; !exists {
-				volumesToReportInUse = append(volumesToReportInUse, volume.VolumeName)
-			}
+			volumesToReportInUse = append(volumesToReportInUse, volume.VolumeName)
 		}
 	}
 
 	slices.Sort(volumesToReportInUse)
-	return volumesToReportInUse
+	return slices.Compact(volumesToReportInUse)
 }
 
 func (vm *volumeManager) ReconcilerStatesHasBeenSynced() bool {