domain: use dedicated lock for expiredTimeStamp4PC (#45802) (#47519)

close #45400

Author: ti-chi-bot

domain/BUILD.bazel

@@ -128,13 +128,16 @@ go_test(
         "//parser/ast",
         "//parser/auth",
         "//parser/model",
+        "//parser/mysql",
         "//parser/terror",
         "//server",
         "//session",
+        "//sessionctx/stmtctx",
         "//sessionctx/variable",
         "//store/mockstore",
         "//testkit",
         "//testkit/testsetup",
+        "//types",
         "//util",
         "//util/mock",
         "//util/replayer",

domain/domain.go

@@ -146,14 +146,19 @@ type Domain struct {
 	memoryUsageAlarmHandle  *memoryusagealarm.Handle
 	serverMemoryLimitHandle *servermemorylimit.Handle
 	// TODO: use Run for each process in future pr
-	wg                    *util.WaitGroupEnhancedWrapper
-	statsUpdating         atomicutil.Int32
-	cancel                context.CancelFunc
-	indexUsageSyncLease   time.Duration
-	dumpFileGcChecker     *dumpFileGcChecker
-	planReplayerHandle    *planReplayerHandle
-	extractTaskHandle     *ExtractHandle
-	expiredTimeStamp4PC   types.Time
+	wg                  *util.WaitGroupEnhancedWrapper
+	statsUpdating       atomicutil.Int32
+	cancel              context.CancelFunc
+	indexUsageSyncLease time.Duration
+	dumpFileGcChecker   *dumpFileGcChecker
+	planReplayerHandle  *planReplayerHandle
+	extractTaskHandle   *ExtractHandle
+	expiredTimeStamp4PC struct {
+		// let `expiredTimeStamp4PC` use its own lock to avoid any block across domain.Reload()
+		// and compiler.Compile(), see issue https://github.com/pingcap/tidb/issues/45400
+		sync.RWMutex
+		expiredTimeStamp types.Time
+	}
 	logBackupAdvancer     *daemon.OwnerDaemon
 	historicalStatsWorker *HistoricalStatsWorker
 	ttlJobManager         atomic.Pointer[ttlworker.JobManager]
@@ -472,18 +477,18 @@ func (do *Domain) GetSnapshotMeta(startTS uint64) (*meta.Meta, error) {
 
 // ExpiredTimeStamp4PC gets expiredTimeStamp4PC from domain.
 func (do *Domain) ExpiredTimeStamp4PC() types.Time {
-	do.m.Lock()
-	defer do.m.Unlock()
+	do.expiredTimeStamp4PC.RLock()
+	defer do.expiredTimeStamp4PC.RUnlock()
 
-	return do.expiredTimeStamp4PC
+	return do.expiredTimeStamp4PC.expiredTimeStamp
 }
 
 // SetExpiredTimeStamp4PC sets the expiredTimeStamp4PC from domain.
 func (do *Domain) SetExpiredTimeStamp4PC(time types.Time) {
-	do.m.Lock()
-	defer do.m.Unlock()
+	do.expiredTimeStamp4PC.Lock()
+	defer do.expiredTimeStamp4PC.Unlock()
 
-	do.expiredTimeStamp4PC = time
+	do.expiredTimeStamp4PC.expiredTimeStamp = time
 }
 
 // DDL gets DDL from domain.
@@ -1021,7 +1026,6 @@ func NewDomain(store kv.Storage, ddlLease time.Duration, statsLease time.Duratio
 		slowQuery:           newTopNSlowQueries(30, time.Hour*24*7, 500),
 		indexUsageSyncLease: idxUsageSyncLease,
 		dumpFileGcChecker:   &dumpFileGcChecker{gcLease: dumpFileGcLease, paths: []string{replayer.GetPlanReplayerDirName(), GetOptimizerTraceDirName(), GetExtractTaskDirName()}},
-		expiredTimeStamp4PC: types.NewTime(types.ZeroCoreTime, mysql.TypeTimestamp, types.DefaultFsp),
 		mdlCheckTableInfo: &mdlCheckTableInfo{
 			mu:         sync.Mutex{},
 			jobsVerMap: make(map[int64]int64),
@@ -1037,6 +1041,7 @@ func NewDomain(store kv.Storage, ddlLease time.Duration, statsLease time.Duratio
 	do.serverMemoryLimitHandle = servermemorylimit.NewServerMemoryLimitHandle(do.exit)
 	do.sysProcesses = SysProcesses{mu: &sync.RWMutex{}, procMap: make(map[uint64]sessionctx.Context)}
 	do.initDomainSysVars()
+	do.expiredTimeStamp4PC.expiredTimeStamp = types.NewTime(types.ZeroCoreTime, mysql.TypeTimestamp, types.DefaultFsp)
 	return do
 }
 

domain/domain_test.go

@@ -34,8 +34,11 @@ import (
 	"github.com/pingcap/tidb/metrics"
 	"github.com/pingcap/tidb/parser/ast"
 	"github.com/pingcap/tidb/parser/model"
+	"github.com/pingcap/tidb/parser/mysql"
+	"github.com/pingcap/tidb/sessionctx/stmtctx"
 	"github.com/pingcap/tidb/sessionctx/variable"
 	"github.com/pingcap/tidb/store/mockstore"
+	"github.com/pingcap/tidb/types"
 	"github.com/pingcap/tidb/util/mock"
 	dto "github.com/prometheus/client_model/go"
 	"github.com/stretchr/testify/require"
@@ -187,6 +190,17 @@ func TestStatWorkRecoverFromPanic(t *testing.T) {
 	scope := dom.GetScope("status")
 	require.Equal(t, variable.DefaultStatusVarScopeFlag, scope)
 
+	// default expiredTimeStamp4PC = "0000-00-00 00:00:00"
+	ts := types.NewTime(types.ZeroCoreTime, mysql.TypeTimestamp, types.DefaultFsp)
+	expiredTimeStamp := dom.ExpiredTimeStamp4PC()
+	require.Equal(t, expiredTimeStamp, ts)
+
+	// set expiredTimeStamp4PC to "2023-08-02 12:15:00"
+	ts, _ = types.ParseTimestamp(&stmtctx.StatementContext{TimeZone: time.UTC}, "2023-08-02 12:15:00")
+	dom.SetExpiredTimeStamp4PC(ts)
+	expiredTimeStamp = dom.ExpiredTimeStamp4PC()
+	require.Equal(t, expiredTimeStamp, ts)
+
 	err = store.Close()
 	require.NoError(t, err)