fix race

Signed-off-by: you06 <[email protected]>

internal/locate/region_cache.go

@@ -452,12 +452,12 @@ func (c *RegionCache) Close() {
 	c.cancelFunc()
 }
 
-var reloadRegionInterval = 10 * time.Second
+var reloadRegionInterval = int64(10 * time.Second)
 
 // asyncCheckAndResolveLoop with
 func (c *RegionCache) asyncCheckAndResolveLoop(interval time.Duration) {
 	ticker := time.NewTicker(interval)
-	reloadRegionTicker := time.NewTicker(reloadRegionInterval)
+	reloadRegionTicker := time.NewTicker(time.Duration(atomic.LoadInt64(&reloadRegionInterval)))
 	defer func() {
 		ticker.Stop()
 		reloadRegionTicker.Stop()

internal/locate/region_request.go

@@ -426,9 +426,9 @@ func (state *tryFollower) next(bo *retry.Backoffer, selector *replicaSelector) (
 		return rpcCtx, err
 	}
 	if state.fallbackFromLeader {
-		replicaRead := true
 		staleRead := false
 		rpcCtx.contextPatcher.staleRead = &staleRead
+		replicaRead := true
 		rpcCtx.contextPatcher.replicaRead = &replicaRead
 	}
 	return rpcCtx, nil
@@ -602,7 +602,9 @@ func (state *accessFollower) next(bo *retry.Backoffer, selector *replicaSelector
 			selector.targetIdx = idx
 			break
 		}
-		if selectReplica.isEpochStale() {
+		if selectReplica.isEpochStale() &&
+			selectReplica.store.getResolveState() == resolved &&
+			selectReplica.store.getLivenessState() == reachable {
 			reloadRegion = true
 		}
 	}
@@ -657,11 +659,9 @@ func (state *accessFollower) isCandidate(idx AccessIndex, replica *replica) bool
 	if replica.isEpochStale() || replica.isExhausted(1) || replica.store.getLivenessState() == unreachable {
 		return false
 	}
-	if state.option.leaderOnly {
+	if state.option.leaderOnly && idx == state.leaderIdx {
 		// The request can only be sent to the leader.
-		if idx == state.leaderIdx {
-			return true
-		}
+		return true
 	} else if !state.tryLeader && idx == state.leaderIdx {
 		// The request cannot be sent to leader.
 		return false

internal/locate/region_request_state_test.go

@@ -249,13 +249,13 @@ func (s *testRegionCacheStaleReadSuite) setTimeout(id uint64) {
 }
 
 func TestRegionCacheStaleRead(t *testing.T) {
-	originReloadRegionInterval := reloadRegionInterval
+	originReloadRegionInterval := atomic.LoadInt64(&reloadRegionInterval)
 	originBoTiKVServerBusy := retry.BoTiKVServerBusy
 	defer func() {
 		reloadRegionInterval = originReloadRegionInterval
 		retry.BoTiKVServerBusy = originBoTiKVServerBusy
 	}()
-	reloadRegionInterval = 24 * time.Hour // disable reload region
+	atomic.StoreInt64(&reloadRegionInterval, int64(24*time.Hour)) // disable reload region
 	retry.BoTiKVServerBusy = retry.NewConfig("tikvServerBusy", &metrics.BackoffHistogramServerBusy, retry.NewBackoffFnCfg(2, 10, retry.EqualJitter), tikverr.ErrTiKVServerBusy)
 	regionCacheTestCases := []RegionCacheTestCase{
 		{

internal/mockstore/mocktikv/cluster.go

@@ -53,14 +53,14 @@ var _ cluster.Cluster = &Cluster{}
 
 // Cluster simulates a TiKV cluster. It focuses on management and the change of
 // meta data. A Cluster mainly includes following 3 kinds of meta data:
-//  1. Region: A Region is a fragment of TiKV's data whose range is [start, end).
-//     The data of a Region is duplicated to multiple Peers and distributed in
-//     multiple Stores.
-//  2. Peer: A Peer is a replica of a Region's data. All peers of a Region form
-//     a group, each group elects a Leader to provide services.
-//  3. Store: A Store is a storage/service node. Try to think it as a TiKV server
-//     process. Only the store with request's Region's leader Peer could respond
-//     to client's request.
+// 1) Region: A Region is a fragment of TiKV's data whose range is [start, end).
+//    The data of a Region is duplicated to multiple Peers and distributed in
+//    multiple Stores.
+// 2) Peer: A Peer is a replica of a Region's data. All peers of a Region form
+//    a group, each group elects a Leader to provide services.
+// 3) Store: A Store is a storage/service node. Try to think it as a TiKV server
+//    process. Only the store with request's Region's leader Peer could respond
+//    to client's request.
 type Cluster struct {
 	sync.RWMutex
 	id      uint64