diff --git a/pkg/util/util.go b/pkg/util/util.go
deleted file mode 100644
index 70b772327..000000000
--- a/pkg/util/util.go
+++ /dev/null
@@ -1,39 +0,0 @@
-package util
-
-import (
-	"k8s.io/apimachinery/pkg/util/sets"
-)
-
-// GetDifferenceSet will get difference set from includeItems and excludeItems.
-func GetDifferenceSet(includeItems, excludeItems []string) []string {
-	if includeItems == nil {
-		includeItems = []string{}
-	}
-	if excludeItems == nil {
-		excludeItems = []string{}
-	}
-	includeSet := sets.NewString()
-	excludeSet := sets.NewString()
-	for _, targetItem := range excludeItems {
-		excludeSet.Insert(targetItem)
-	}
-	for _, targetItem := range includeItems {
-		includeSet.Insert(targetItem)
-	}
-
-	matchItems := includeSet.Difference(excludeSet)
-
-	return matchItems.List()
-}
-
-// GetUniqueElements will delete duplicate element in list.
-func GetUniqueElements(list []string) []string {
-	if list == nil {
-		return []string{}
-	}
-	result := sets.String{}
-	for _, item := range list {
-		result.Insert(item)
-	}
-	return result.List()
-}