Use anonymous function for locking when serving health probes

Updates serveHealthProbes to use the same anonymous function pattern
that serveMetrics does for performing operations that necessitate
acquiring the controller manager's lock.

Signed-off-by: hasheddan <georgedanielmangum@gmail.com>

pkg/manager/internal.go

@@ -418,34 +418,35 @@ func (cm *controllerManager) serveMetrics() {
 }
 
 func (cm *controllerManager) serveHealthProbes() {
-	// TODO(hypnoglow): refactor locking to use anonymous func in the similar way
-	// it's done in serveMetrics.
-	cm.mu.Lock()
 	mux := http.NewServeMux()
-
-	if cm.readyzHandler != nil {
-		mux.Handle(cm.readinessEndpointName, http.StripPrefix(cm.readinessEndpointName, cm.readyzHandler))
-		// Append '/' suffix to handle subpaths
-		mux.Handle(cm.readinessEndpointName+"/", http.StripPrefix(cm.readinessEndpointName, cm.readyzHandler))
-	}
-	if cm.healthzHandler != nil {
-		mux.Handle(cm.livenessEndpointName, http.StripPrefix(cm.livenessEndpointName, cm.healthzHandler))
-		// Append '/' suffix to handle subpaths
-		mux.Handle(cm.livenessEndpointName+"/", http.StripPrefix(cm.livenessEndpointName, cm.healthzHandler))
-	}
-
 	server := http.Server{
 		Handler: mux,
 	}
-	// Run server
-	cm.startRunnable(RunnableFunc(func(_ context.Context) error {
-		if err := server.Serve(cm.healthProbeListener); err != nil && err != http.ErrServerClosed {
-			return err
+
+	func() {
+		cm.mu.Lock()
+		defer cm.mu.Unlock()
+
+		if cm.readyzHandler != nil {
+			mux.Handle(cm.readinessEndpointName, http.StripPrefix(cm.readinessEndpointName, cm.readyzHandler))
+			// Append '/' suffix to handle subpaths
+			mux.Handle(cm.readinessEndpointName+"/", http.StripPrefix(cm.readinessEndpointName, cm.readyzHandler))
 		}
-		return nil
-	}))
-	cm.healthzStarted = true
-	cm.mu.Unlock()
+		if cm.healthzHandler != nil {
+			mux.Handle(cm.livenessEndpointName, http.StripPrefix(cm.livenessEndpointName, cm.healthzHandler))
+			// Append '/' suffix to handle subpaths
+			mux.Handle(cm.livenessEndpointName+"/", http.StripPrefix(cm.livenessEndpointName, cm.healthzHandler))
+		}
+
+		// Run server
+		cm.startRunnable(RunnableFunc(func(_ context.Context) error {
+			if err := server.Serve(cm.healthProbeListener); err != nil && err != http.ErrServerClosed {
+				return err
+			}
+			return nil
+		}))
+		cm.healthzStarted = true
+	}()
 
 	// Shutdown the server when stop is closed
 	<-cm.internalProceduresStop