From 476d9b3128cd090bf1dbbbbe83ddf8c0316a64b5 Mon Sep 17 00:00:00 2001
From: Jianjun Liao <36503113+Leavrth@users.noreply.github.com>
Date: Mon, 16 Oct 2023 13:09:28 +0800
Subject: [PATCH] br: lock the call of update stats meta (#47610)

ref pingcap/tidb#47596
---
 br/pkg/backup/schema.go  | 8 ++++----
 br/pkg/restore/client.go | 7 +++++++
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/br/pkg/backup/schema.go b/br/pkg/backup/schema.go
index eb9f910cb0b2a..259b891dfce9a 100644
--- a/br/pkg/backup/schema.go
+++ b/br/pkg/backup/schema.go
@@ -147,7 +147,7 @@ func (ss *Schemas) BackupSchemas(
 					}
 				}
 				if statsHandle != nil {
-					if err := schema.dumpStatsToJSON(statsHandle); err != nil {
+					if err := schema.dumpStatsToJSON(statsHandle, backupTS); err != nil {
 						logger.Error("dump table stats failed", logutil.ShortError(err))
 					}
 				}
@@ -209,9 +209,9 @@ func (s *schemaInfo) calculateChecksum(
 	return nil
 }
 
-func (s *schemaInfo) dumpStatsToJSON(statsHandle *handle.Handle) error {
-	jsonTable, err := statsHandle.DumpStatsToJSON(
-		s.dbInfo.Name.String(), s.tableInfo, nil, true)
+func (s *schemaInfo) dumpStatsToJSON(statsHandle *handle.Handle, backupTS uint64) error {
+	jsonTable, err := statsHandle.DumpStatsToJSONBySnapshot(
+		s.dbInfo.Name.String(), s.tableInfo, backupTS, true)
 	if err != nil {
 		return errors.Trace(err)
 	}
diff --git a/br/pkg/restore/client.go b/br/pkg/restore/client.go
index c79b45673e42a..a8e8d6a5135ea 100644
--- a/br/pkg/restore/client.go
+++ b/br/pkg/restore/client.go
@@ -1758,6 +1758,9 @@ func (rc *Client) GoUpdateMetaAndLoadStats(ctx context.Context, inCh <-chan *Cre
 	log.Info("Start to update meta then load stats")
 	outCh := DefaultOutputTableChan()
 	workers := utils.NewWorkerPool(16, "UpdateStats")
+	// The rc.db is not thread safe
+	var updateMetaLock sync.Mutex
+
 	go concurrentHandleTablesCh(ctx, inCh, outCh, errCh, workers, func(c context.Context, tbl *CreatedTable) error {
 		oldTable := tbl.OldTable
 		// Not need to return err when failed because of update analysis-meta
@@ -1765,6 +1768,8 @@ func (rc *Client) GoUpdateMetaAndLoadStats(ctx context.Context, inCh <-chan *Cre
 		if err != nil {
 			log.Error("getTS failed", zap.Error(err))
 		} else {
+			updateMetaLock.Lock()
+
 			log.Info("start update metas",
 				zap.Stringer("table", oldTable.Info.Name),
 				zap.Stringer("db", oldTable.DB.Name))
@@ -1772,6 +1777,8 @@ func (rc *Client) GoUpdateMetaAndLoadStats(ctx context.Context, inCh <-chan *Cre
 			if err != nil {
 				log.Error("update stats meta failed", zap.Any("table", tbl.Table), zap.Error(err))
 			}
+
+			updateMetaLock.Unlock()
 		}
 
 		if oldTable.Stats != nil {