fixes data races

pkg/kubelet/config/file_linux_test.go

@@ -131,6 +131,7 @@ func TestWatchFileChanged(t *testing.T) {
 }
 
 type testCase struct {
+	lock       *sync.Mutex
 	desc       string
 	linkedFile string
 	pod        runtime.Object
@@ -141,6 +142,7 @@ func getTestCases(hostname types.NodeName) []*testCase {
 	grace := int64(30)
 	return []*testCase{
 		{
+			lock: &sync.Mutex{},
 			desc: "Simple pod",
 			pod: &v1.Pod{
 				TypeMeta: metav1.TypeMeta{
@@ -304,11 +306,10 @@ func watchFileChanged(watchDir bool, symlink bool, t *testing.T) {
 			}
 
 			var file string
-			lock := &sync.Mutex{}
 			ch := make(chan interface{})
 			func() {
-				lock.Lock()
-				defer lock.Unlock()
+				testCase.lock.Lock()
+				defer testCase.lock.Unlock()
 
 				if symlink {
 					file = testCase.writeToFile(linkedDirName, fileName, t)
@@ -332,8 +333,8 @@ func watchFileChanged(watchDir bool, symlink bool, t *testing.T) {
 
 			changeFile := func() {
 				// Edit the file content
-				lock.Lock()
-				defer lock.Unlock()
+				testCase.lock.Lock()
+				defer testCase.lock.Unlock()
 
 				pod := testCase.pod.(*v1.Pod)
 				pod.Spec.Containers[0].Name = "image2"
@@ -352,9 +353,7 @@ func watchFileChanged(watchDir bool, symlink bool, t *testing.T) {
 			expectUpdate(t, ch, testCase)
 
 			if watchDir {
-				from := fileName
-				fileName = fileName + "_ch"
-				go changeFileName(dirName, from, fileName, t)
+				go changeFileName(dirName, fileName, fileName+"_ch", t)
 				// expect an update by MOVED_FROM inotify event cause changing file name
 				expectEmptyUpdate(t, ch)
 				// expect an update by MOVED_TO inotify event cause changing file name
@@ -365,8 +364,12 @@ func watchFileChanged(watchDir bool, symlink bool, t *testing.T) {
 }
 
 func deleteFile(dir, file string, ch chan interface{}, t *testing.T) {
+	path := filepath.Join(dir, file)
+	if _, err := os.Stat(path); err != nil {
+		// The file might absent if it's renamed, deleted..
+		return
+	}
 	go func() {
-		path := filepath.Join(dir, file)
 		err := os.Remove(path)
 		if err != nil {
 			t.Errorf("unable to remove test file %s: %s", path, err)
@@ -397,6 +400,8 @@ func expectUpdate(t *testing.T, ch chan interface{}, testCase *testCase) {
 				}
 			}
 
+			testCase.lock.Lock()
+			defer testCase.lock.Unlock()
 			if !apiequality.Semantic.DeepEqual(testCase.expected, update) {
 				t.Fatalf("%s: Expected: %#v, Got: %#v", testCase.desc, testCase.expected, update)
 			}