[aggregator] Fix checkCampaignStateLoop (#2867)

src/aggregator/aggregator/election_mgr.go

@@ -572,33 +572,28 @@ func (mgr *electionManager) campaignState() campaignState {
 	return mgr.campaignStateWatchable.Get().(campaignState)
 }
 
+func (mgr *electionManager) checkCampaignState() {
+	enabled, err := mgr.campaignIsEnabledFn()
+	if err != nil {
+		mgr.metrics.campaignCheckErrors.Inc(1)
+		return
+	}
+	newState := newCampaignState(enabled)
+	currState := mgr.campaignState()
+	if currState == newState {
+		return
+	}
+	mgr.processCampaignStateChange(newState)
+}
+
 func (mgr *electionManager) checkCampaignStateLoop() {
 	defer mgr.Done()
 
 	ticker := time.NewTicker(mgr.campaignStateCheckInterval)
 	defer ticker.Stop()
 
 	for {
-		select {
-		case <-mgr.doneCh:
-			return
-		default:
-		}
-
-		enabled, err := mgr.campaignIsEnabledFn()
-		if err != nil {
-			mgr.metrics.campaignCheckErrors.Inc(1)
-
-			continue
-		}
-		newState := newCampaignState(enabled)
-		currState := mgr.campaignState()
-		if currState == newState {
-			continue
-		}
-		mgr.processCampaignStateChange(newState)
-
-		// block on ticker or exit signal
+		mgr.checkCampaignState()
 		select {
 		case <-ticker.C:
 		case <-mgr.doneCh: