fix the data race problem

Signed-off-by: Ryan Leung <rleungx@gmail.com>

Author: rleungx

server/config/persist_options.go

@@ -495,6 +495,11 @@ func (o *PersistOptions) GetHotRegionCacheHitsThreshold() int {
 	return int(o.GetScheduleConfig().HotRegionCacheHitsThreshold)
 }
 
+// GetStoresLimit gets the stores' limit.
+func (o *PersistOptions) GetStoresLimit() map[uint64]StoreLimitConfig {
+	return o.GetScheduleConfig().StoreLimit
+}
+
 // GetSchedulers gets the scheduler configurations.
 func (o *PersistOptions) GetSchedulers() SchedulerConfigs {
 	return o.GetScheduleConfig().Schedulers

server/server.go

@@ -785,9 +785,7 @@ func (s *Server) GetConfig() *config.Config {
 
 // GetScheduleConfig gets the balance config information.
 func (s *Server) GetScheduleConfig() *config.ScheduleConfig {
-	cfg := &config.ScheduleConfig{}
-	*cfg = *s.persistOptions.GetScheduleConfig()
-	return cfg
+	return s.persistOptions.GetScheduleConfig().Clone()
 }
 
 // SetScheduleConfig sets the balance config information.
@@ -815,9 +813,7 @@ func (s *Server) SetScheduleConfig(cfg config.ScheduleConfig) error {
 
 // GetReplicationConfig get the replication config.
 func (s *Server) GetReplicationConfig() *config.ReplicationConfig {
-	cfg := &config.ReplicationConfig{}
-	*cfg = *s.persistOptions.GetReplicationConfig()
-	return cfg
+	return s.persistOptions.GetReplicationConfig().Clone()
 }
 
 // SetReplicationConfig sets the replication config.
@@ -905,9 +901,7 @@ func (s *Server) SetReplicationConfig(cfg config.ReplicationConfig) error {
 
 // GetPDServerConfig gets the balance config information.
 func (s *Server) GetPDServerConfig() *config.PDServerConfig {
-	cfg := &config.PDServerConfig{}
-	*cfg = *s.persistOptions.GetPDServerConfig()
-	return cfg
+	return s.persistOptions.GetPDServerConfig().Clone()
 }
 
 // SetPDServerConfig sets the server config.

server/statistics/store_collection.go

@@ -187,7 +187,8 @@ func (s *storeStatistics) Collect() {
 		placementStatusGauge.WithLabelValues(labelType, name).Set(float64(value))
 	}
 
-	for storeID, limit := range s.opt.GetScheduleConfig().StoreLimit {
+	storesLimit := s.opt.GetStoresLimit()
+	for storeID, limit := range storesLimit {
 		id := strconv.FormatUint(storeID, 10)
 		StoreLimitGauge.WithLabelValues(id, "add-peer").Set(limit.AddPeer)
 		StoreLimitGauge.WithLabelValues(id, "remove-peer").Set(limit.RemovePeer)