do init limiter if needed

store/tikv/2pc.go

@@ -117,7 +117,8 @@ type twoPhaseCommitter struct {
 
 // batchExecutor is txn controller providing rate control like utils
 type batchExecutor struct {
-	rateLimiter *rateLimit           // rate limit for concurrency control, maybe more strategies
+	rateLim     int                  // concurrent worker numbers
+	rateLimiter *rateLimit           // rate limiter for concurrency control, maybe more strategies
 	committer   *twoPhaseCommitter   // here maybe more different type committer in the future
 	action      twoPhaseCommitAction // the work action type
 	procFn      procOneBatchFn       // injected proc batch function
@@ -1011,10 +1012,17 @@ func appendBatchBySize(b []batchKeys, region RegionVerID, keys [][]byte, sizeFn
 // newBatchExecutor create processor to handle concurrent batch works(prewrite/commit etc)
 func newBatchExecutor(rateLimit int, committer *twoPhaseCommitter,
 	action twoPhaseCommitAction, procFn procOneBatchFn, backoffer *Backoffer) *batchExecutor {
-	return &batchExecutor{newRateLimit(rateLimit), committer,
+	return &batchExecutor{rateLimit, nil, committer,
 		action, procFn, backoffer}
 }
 
+// initUtils do initialize batchExecutor related policies like rateLimit util
+func (batchExe *batchExecutor) initUtils() error {
+	// init rateLimiter by injected rate limit number
+	batchExe.rateLimiter = newRateLimit(batchExe.rateLim)
+	return nil
+}
+
 // startWork concurrently do the work for each batch considering rate limit
 func (batchExe *batchExecutor) startWorker(exitCh chan struct{}, ch chan error, batches []batchKeys) {
 	for idx, batch1 := range batches {
@@ -1066,6 +1074,12 @@ func (batchExe *batchExecutor) process(batches []batchKeys) error {
 		}
 		return errors.Trace(e)
 	}
+	err = batchExe.initUtils()
+	if err != nil {
+		logutil.Logger(batchExe.backoffer.ctx).Error("batchExecutor initUtils failed", zap.Error(err))
+		return err
+	}
+
 	// For prewrite, stop sending other requests after receiving first error.
 	backoffer := batchExe.backoffer
 	var cancel context.CancelFunc