*: simplify some code

server/cluster/cluster.go

@@ -680,7 +680,7 @@ func (c *RaftCluster) processRegionHeartbeat(region *core.RegionInfo) error {
 	}
 
 	if c.regionStats != nil {
-		c.regionStats.Observe(region, c.takeRegionStoresLocked(region))
+		c.regionStats.Observe(region, c.getRegionStoresLocked(region))
 	}
 
 	for _, writeItem := range writeItems {
@@ -1339,14 +1339,14 @@ func (c *RaftCluster) updateRegionsLabelLevelStats(regions []*core.RegionInfo) {
 	c.Lock()
 	defer c.Unlock()
 	for _, region := range regions {
-		c.labelLevelStats.Observe(region, c.takeRegionStoresLocked(region), c.opt.GetLocationLabels())
+		c.labelLevelStats.Observe(region, c.getRegionStoresLocked(region), c.opt.GetLocationLabels())
 	}
 }
 
-func (c *RaftCluster) takeRegionStoresLocked(region *core.RegionInfo) []*core.StoreInfo {
+func (c *RaftCluster) getRegionStoresLocked(region *core.RegionInfo) []*core.StoreInfo {
 	stores := make([]*core.StoreInfo, 0, len(region.GetPeers()))
 	for _, p := range region.GetPeers() {
-		if store := c.core.TakeStore(p.StoreId); store != nil {
+		if store := c.core.GetStore(p.StoreId); store != nil {
 			stores = append(stores, store)
 		}
 	}

server/core/basic_cluster.go

@@ -282,13 +282,6 @@ func (bc *BasicCluster) DeleteStore(store *StoreInfo) {
 	bc.Stores.DeleteStore(store)
 }
 
-// TakeStore returns the point of the origin StoreInfo with the specified storeID.
-func (bc *BasicCluster) TakeStore(storeID uint64) *StoreInfo {
-	bc.RLock()
-	defer bc.RUnlock()
-	return bc.Stores.TakeStore(storeID)
-}
-
 // PreCheckPutRegion checks if the region is valid to put.
 func (bc *BasicCluster) PreCheckPutRegion(region *RegionInfo) (*RegionInfo, error) {
 	bc.RLock()

server/core/store.go

@@ -515,15 +515,6 @@ func (s *StoresInfo) GetStore(storeID uint64) *StoreInfo {
 	return store
 }
 
-// TakeStore returns the point of the origin StoreInfo with the specified storeID.
-func (s *StoresInfo) TakeStore(storeID uint64) *StoreInfo {
-	store, ok := s.stores[storeID]
-	if !ok {
-		return nil
-	}
-	return store
-}
-
 // SetStore sets a StoreInfo with storeID.
 func (s *StoresInfo) SetStore(store *StoreInfo) {
 	s.stores[store.GetID()] = store

server/schedule/checker/rule_checker_test.go

@@ -341,7 +341,7 @@ func (s *testRuleCheckerSuite) TestIssue2419(c *C) {
 // Ref https://github.com/tikv/pd/issues/3521
 // The problem is when offline a store, we may add learner multiple times if
 // the operator is timeout.
-func (s *testRuleCheckerSuite) TestIssue3521_PriorityFixOrphanPeer(c *C) {
+func (s *testRuleCheckerSuite) TestPriorityFixOrphanPeer(c *C) {
 	s.cluster.AddLabelsStore(1, 1, map[string]string{"host": "host1"})
 	s.cluster.AddLabelsStore(2, 1, map[string]string{"host": "host1"})
 	s.cluster.AddLabelsStore(3, 1, map[string]string{"host": "host2"})
@@ -392,7 +392,7 @@ func (s *testRuleCheckerSuite) TestIssue3293(c *C) {
 		},
 	})
 	c.Assert(err, IsNil)
-	s.cluster.DeleteStore(s.cluster.TakeStore(5))
+	s.cluster.DeleteStore(s.cluster.GetStore(5))
 	err = s.ruleManager.SetRule(&placement.Rule{
 		GroupID: "TiDB_DDL_51",
 		ID:      "default",

server/schedule/operator_controller.go

@@ -641,85 +641,29 @@ func (oc *OperatorController) SendScheduleCommand(region *core.RegionInfo, step
 			// The newly added peer is pending.
 			return
 		}
-		cmd = &pdpb.RegionHeartbeatResponse{
-			ChangePeer: &pdpb.ChangePeer{
-				ChangeType: eraftpb.ConfChangeType_AddNode,
-				Peer: &metapb.Peer{
-					Id:      st.PeerID,
-					StoreId: st.ToStore,
-					Role:    metapb.PeerRole_Voter,
-				},
-			},
-		}
+		cmd = addNode(st.PeerID, st.ToStore)
 	case operator.AddLightPeer:
 		if region.GetStorePeer(st.ToStore) != nil {
 			// The newly added peer is pending.
 			return
 		}
-		cmd = &pdpb.RegionHeartbeatResponse{
-			ChangePeer: &pdpb.ChangePeer{
-				ChangeType: eraftpb.ConfChangeType_AddNode,
-				Peer: &metapb.Peer{
-					Id:      st.PeerID,
-					StoreId: st.ToStore,
-					Role:    metapb.PeerRole_Voter,
-				},
-			},
-		}
+		cmd = addNode(st.PeerID, st.ToStore)
 	case operator.AddLearner:
 		if region.GetStorePeer(st.ToStore) != nil {
 			// The newly added peer is pending.
 			return
 		}
-		cmd = &pdpb.RegionHeartbeatResponse{
-			ChangePeer: &pdpb.ChangePeer{
-				ChangeType: eraftpb.ConfChangeType_AddLearnerNode,
-				Peer: &metapb.Peer{
-					Id:      st.PeerID,
-					StoreId: st.ToStore,
-					Role:    metapb.PeerRole_Learner,
-				},
-			},
-		}
+		cmd = addLearnerNode(st.PeerID, st.ToStore)
 	case operator.AddLightLearner:
 		if region.GetStorePeer(st.ToStore) != nil {
 			// The newly added peer is pending.
 			return
 		}
-		cmd = &pdpb.RegionHeartbeatResponse{
-			ChangePeer: &pdpb.ChangePeer{
-				ChangeType: eraftpb.ConfChangeType_AddLearnerNode,
-				Peer: &metapb.Peer{
-					Id:      st.PeerID,
-					StoreId: st.ToStore,
-					Role:    metapb.PeerRole_Learner,
-				},
-			},
-		}
+		cmd = addLearnerNode(st.PeerID, st.ToStore)
 	case operator.PromoteLearner:
-		cmd = &pdpb.RegionHeartbeatResponse{
-			ChangePeer: &pdpb.ChangePeer{
-				// reuse AddNode type
-				ChangeType: eraftpb.ConfChangeType_AddNode,
-				Peer: &metapb.Peer{
-					Id:      st.PeerID,
-					StoreId: st.ToStore,
-					Role:    metapb.PeerRole_Voter,
-				},
-			},
-		}
+		cmd = addNode(st.PeerID, st.ToStore)
 	case operator.DemoteFollower:
-		cmd = &pdpb.RegionHeartbeatResponse{
-			ChangePeer: &pdpb.ChangePeer{
-				// reuse AddLearnerNode type
-				ChangeType: eraftpb.ConfChangeType_AddLearnerNode,
-				Peer: &metapb.Peer{
-					Id:      st.PeerID,
-					StoreId: st.ToStore,
-					Role:    metapb.PeerRole_Learner,
-				},
-			},
-		}
+		cmd = addLearnerNode(st.PeerID, st.ToStore)
 	case operator.RemovePeer:
 		cmd = &pdpb.RegionHeartbeatResponse{
 			ChangePeer: &pdpb.ChangePeer{
@@ -758,6 +702,32 @@ func (oc *OperatorController) SendScheduleCommand(region *core.RegionInfo, step
 	oc.hbStreams.SendMsg(region, cmd)
 }
 
+func addNode(id, storeID uint64) *pdpb.RegionHeartbeatResponse {
+	return &pdpb.RegionHeartbeatResponse{
+		ChangePeer: &pdpb.ChangePeer{
+			ChangeType: eraftpb.ConfChangeType_AddNode,
+			Peer: &metapb.Peer{
+				Id:      id,
+				StoreId: storeID,
+				Role:    metapb.PeerRole_Voter,
+			},
+		},
+	}
+}
+
+func addLearnerNode(id, storeID uint64) *pdpb.RegionHeartbeatResponse {
+	return &pdpb.RegionHeartbeatResponse{
+		ChangePeer: &pdpb.ChangePeer{
+			ChangeType: eraftpb.ConfChangeType_AddLearnerNode,
+			Peer: &metapb.Peer{
+				Id:      id,
+				StoreId: storeID,
+				Role:    metapb.PeerRole_Learner,
+			},
+		},
+	}
+}
+
 func (oc *OperatorController) pushHistory(op *operator.Operator) {
 	oc.Lock()
 	defer oc.Unlock()

server/statistics/hot_peer_cache_test.go

@@ -277,6 +277,7 @@ func (t *testHotPeerCache) TestThresholdWithUpdateHotPeerStat(c *C) {
 	t.testMetrics(c, 17., byteRate, expectThreshold)
 	t.testMetrics(c, 1., byteRate, expectThreshold)
 }
+
 func (t *testHotPeerCache) testMetrics(c *C, interval, byteRate, expectThreshold float64) {
 	cache := NewHotStoresStats(ReadFlow)
 	minThresholds := minHotThresholds[cache.kind]