fix data race

Signed-off-by: Neil Shen <[email protected]>

pkg/workerpool/pool_test.go

@@ -432,14 +432,19 @@ func TestSynchronizeLog(t *testing.T) {
 	// Always report "synchronize is taking too long".
 	w.slowSynchronizeThreshold = time.Duration(0)
 	w.slowSynchronizeLimiter = rate.NewLimiter(rate.Every(100*time.Minute), 1)
-	go w.synchronize()
 
 	counter := int32(0)
 	logWarn = func(msg string, fields ...zap.Field) {
 		atomic.AddInt32(&counter, 1)
 	}
 	defer func() { logWarn = log.Warn }()
 
+	doneCh := make(chan struct{})
+	go func() {
+		w.synchronize()
+		close(doneCh)
+	}()
+
 	time.Sleep(300 * time.Millisecond)
 	w.stopNotifier.Notify()
 	time.Sleep(300 * time.Millisecond)
@@ -448,6 +453,7 @@ func TestSynchronizeLog(t *testing.T) {
 	// Close worker.
 	atomic.StoreInt32(&w.isRunning, 0)
 	w.stopNotifier.Close()
+	<-doneCh
 
 	require.EqualValues(t, 1, atomic.LoadInt32(&counter))
 }