adding trace to reflector initialization

staging/src/k8s.io/client-go/tools/cache/reflector.go

@@ -40,6 +40,7 @@ import (
 	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
 	"k8s.io/apimachinery/pkg/util/wait"
 	"k8s.io/apimachinery/pkg/watch"
+	utiltrace "k8s.io/apiserver/pkg/util/trace"
 	"k8s.io/klog"
 )
 
@@ -175,47 +176,57 @@ func (r *Reflector) ListAndWatch(stopCh <-chan struct{}) error {
 	options := metav1.ListOptions{ResourceVersion: "0"}
 	r.metrics.numberOfLists.Inc()
 	start := r.clock.Now()
-
-	var list runtime.Object
-	var err error
-	listCh := make(chan struct{}, 1)
-	panicCh := make(chan interface{}, 1)
-	go func() {
-		defer func() {
-			if r := recover(); r != nil {
-				panicCh <- r
-			}
+	if err := func() error {
+		trace := utiltrace.New("Reflector_" + r.name + "_ListAndWatch")
+		defer trace.LogIfLong(10 * time.Second)
+		var list runtime.Object
+		var err error
+		listCh := make(chan struct{}, 1)
+		panicCh := make(chan interface{}, 1)
+		go func() {
+			defer func() {
+				if r := recover(); r != nil {
+					panicCh <- r
+				}
+			}()
+			list, err = r.listerWatcher.List(options)
+			close(listCh)
 		}()
-		list, err = r.listerWatcher.List(options)
-		close(listCh)
-	}()
-	select {
-	case <-stopCh:
+		select {
+		case <-stopCh:
+			return nil
+		case r := <-panicCh:
+			panic(r)
+		case <-listCh:
+		}
+		if err != nil {
+			return fmt.Errorf("%s: Failed to list %v: %v", r.name, r.expectedType, err)
+		}
+		trace.Step("Objects listed")
+		r.metrics.listDuration.Observe(time.Since(start).Seconds())
+		listMetaInterface, err := meta.ListAccessor(list)
+		if err != nil {
+			return fmt.Errorf("%s: Unable to understand list result %#v: %v", r.name, list, err)
+		}
+		resourceVersion = listMetaInterface.GetResourceVersion()
+		trace.Step("Resource version extracted")
+		items, err := meta.ExtractList(list)
+		if err != nil {
+			return fmt.Errorf("%s: Unable to understand list result %#v (%v)", r.name, list, err)
+		}
+		trace.Step("Objects extracted")
+		r.metrics.numberOfItemsInList.Observe(float64(len(items)))
+		if err := r.syncWith(items, resourceVersion); err != nil {
+			return fmt.Errorf("%s: Unable to sync list result: %v", r.name, err)
+		}
+		trace.Step("SyncWith done")
+		r.setLastSyncResourceVersion(resourceVersion)
+		trace.Step("Resource version updated")
 		return nil
-	case r := <-panicCh:
-		panic(r)
-	case <-listCh:
-	}
-	if err != nil {
-		return fmt.Errorf("%s: Failed to list %v: %v", r.name, r.expectedType, err)
+	}(); err != nil {
+		return err
 	}
 
-	r.metrics.listDuration.Observe(time.Since(start).Seconds())
-	listMetaInterface, err := meta.ListAccessor(list)
-	if err != nil {
-		return fmt.Errorf("%s: Unable to understand list result %#v: %v", r.name, list, err)
-	}
-	resourceVersion = listMetaInterface.GetResourceVersion()
-	items, err := meta.ExtractList(list)
-	if err != nil {
-		return fmt.Errorf("%s: Unable to understand list result %#v (%v)", r.name, list, err)
-	}
-	r.metrics.numberOfItemsInList.Observe(float64(len(items)))
-	if err := r.syncWith(items, resourceVersion); err != nil {
-		return fmt.Errorf("%s: Unable to sync list result: %v", r.name, err)
-	}
-	r.setLastSyncResourceVersion(resourceVersion)
-
 	resyncerrc := make(chan error, 1)
 	cancelCh := make(chan struct{})
 	defer close(cancelCh)
@@ -285,7 +296,6 @@ func (r *Reflector) ListAndWatch(stopCh <-chan struct{}) error {
 			}
 			return nil
 		}
-
 		if err := r.watchHandler(w, &resourceVersion, resyncerrc, stopCh); err != nil {
 			if err != errorStopRequested {
 				klog.Warningf("%s: watch of %v ended with: %v", r.name, r.expectedType, err)