txn: remove legacy.SimpleTxnContextProvider

executor/BUILD.bazel

@@ -132,7 +132,6 @@ go_library(
         "//sessionctx/stmtctx",
         "//sessionctx/variable",
         "//sessiontxn",
-        "//sessiontxn/legacy",
         "//sessiontxn/staleread",
         "//statistics",
         "//statistics/handle",

executor/builder.go

@@ -49,7 +49,6 @@ import (
 	"github.com/pingcap/tidb/sessionctx/stmtctx"
 	"github.com/pingcap/tidb/sessionctx/variable"
 	"github.com/pingcap/tidb/sessiontxn"
-	"github.com/pingcap/tidb/sessiontxn/legacy"
 	"github.com/pingcap/tidb/sessiontxn/staleread"
 	"github.com/pingcap/tidb/statistics"
 	"github.com/pingcap/tidb/store/helper"
@@ -88,14 +87,11 @@ var (
 // executorBuilder builds an Executor from a Plan.
 // The InfoSchema must not change during execution.
 type executorBuilder struct {
-	ctx              sessionctx.Context
-	is               infoschema.InfoSchema
-	snapshotTS       uint64 // The ts for snapshot-read. A select statement without for update will use this ts
-	forUpdateTS      uint64 // The ts should be used by insert/update/delete/select-for-update statement
-	snapshotTSCached bool
-	err              error // err is set when there is error happened during Executor building process.
-	hasLock          bool
-	Ti               *TelemetryInfo
+	ctx     sessionctx.Context
+	is      infoschema.InfoSchema
+	err     error // err is set when there is error happened during Executor building process.
+	hasLock bool
+	Ti      *TelemetryInfo
 	// isStaleness means whether this statement use stale read.
 	isStaleness      bool
 	readReplicaScope string
@@ -121,26 +117,13 @@ type CTEStorages struct {
 }
 
 func newExecutorBuilder(ctx sessionctx.Context, is infoschema.InfoSchema, ti *TelemetryInfo, replicaReadScope string) *executorBuilder {
-	b := &executorBuilder{
+	return &executorBuilder{
 		ctx:              ctx,
 		is:               is,
 		Ti:               ti,
 		isStaleness:      staleread.IsStmtStaleness(ctx),
 		readReplicaScope: replicaReadScope,
 	}
-
-	txnManager := sessiontxn.GetTxnManager(ctx)
-	if provider, ok := txnManager.GetContextProvider().(*legacy.SimpleTxnContextProvider); ok {
-		provider.GetReadTSFunc = b.getReadTS
-		provider.GetForUpdateTSFunc = func() (uint64, error) {
-			if b.forUpdateTS != 0 {
-				return b.forUpdateTS, nil
-			}
-			return b.getReadTS()
-		}
-	}
-
-	return b
 }
 
 // MockPhysicalPlan is used to return a specified executor in when build.
@@ -660,8 +643,6 @@ func (b *executorBuilder) buildSelectLock(v *plannercore.PhysicalLock) Executor
 	if b.err = b.updateForUpdateTSIfNeeded(v.Children()[0]); b.err != nil {
 		return nil
 	}
-	// Build 'select for update' using the 'for update' ts.
-	b.forUpdateTS = b.ctx.GetSessionVars().TxnCtx.GetForUpdateTS()
 
 	src := b.build(v.Children()[0])
 	if b.err != nil {
@@ -872,7 +853,6 @@ func (b *executorBuilder) buildInsert(v *plannercore.Insert) Executor {
 			return nil
 		}
 	}
-	b.forUpdateTS = b.ctx.GetSessionVars().TxnCtx.GetForUpdateTS()
 	selectExec := b.build(v.SelectPlan)
 	if b.err != nil {
 		return nil
@@ -1578,44 +1558,6 @@ func (b *executorBuilder) getSnapshotTS() (uint64, error) {
 	return txnManager.GetStmtReadTS()
 }
 
-// getReadTS returns the ts used by select (without for-update clause). The return value is affected by the isolation level
-// and some stale/historical read contexts. For example, it will return txn.StartTS in RR and return
-// the current timestamp in RC isolation
-func (b *executorBuilder) getReadTS() (uint64, error) {
-	failpoint.Inject("assertNotStaleReadForExecutorGetReadTS", func() {
-		// after refactoring stale read will use its own context provider
-		staleread.AssertStmtStaleness(b.ctx, false)
-	})
-
-	if b.snapshotTSCached {
-		return b.snapshotTS, nil
-	}
-
-	if snapshotTS := b.ctx.GetSessionVars().SnapshotTS; snapshotTS != 0 {
-		b.snapshotTS = snapshotTS
-		b.snapshotTSCached = true
-		return snapshotTS, nil
-	}
-
-	if b.snapshotTS != 0 {
-		b.snapshotTSCached = true
-		// Return the cached value.
-		return b.snapshotTS, nil
-	}
-
-	txn, err := b.ctx.Txn(true)
-	if err != nil {
-		return 0, err
-	}
-
-	b.snapshotTS = txn.StartTS()
-	if b.snapshotTS == 0 {
-		return 0, errors.Trace(ErrGetStartTS)
-	}
-	b.snapshotTSCached = true
-	return b.snapshotTS, nil
-}
-
 func (b *executorBuilder) buildMemTable(v *plannercore.PhysicalMemTable) Executor {
 	switch v.DBName.L {
 	case util.MetricSchemaName.L:
@@ -2117,7 +2059,6 @@ func (b *executorBuilder) buildUpdate(v *plannercore.Update) Executor {
 	if b.err = b.updateForUpdateTSIfNeeded(v.SelectPlan); b.err != nil {
 		return nil
 	}
-	b.forUpdateTS = b.ctx.GetSessionVars().TxnCtx.GetForUpdateTS()
 	selExec := b.build(v.SelectPlan)
 	if b.err != nil {
 		return nil
@@ -2174,7 +2115,6 @@ func (b *executorBuilder) buildDelete(v *plannercore.Delete) Executor {
 	if b.err = b.updateForUpdateTSIfNeeded(v.SelectPlan); b.err != nil {
 		return nil
 	}
-	b.forUpdateTS = b.ctx.GetSessionVars().TxnCtx.GetForUpdateTS()
 	selExec := b.build(v.SelectPlan)
 	if b.err != nil {
 		return nil

executor/stale_txn_test.go

@@ -34,10 +34,8 @@ import (
 func enableStaleReadCommonFailPoint(t *testing.T) func() {
 	require.NoError(t, failpoint.Enable("github.com/pingcap/tidb/executor/assertStaleReadValuesSameWithExecuteAndBuilder", "return"))
 	require.NoError(t, failpoint.Enable("github.com/pingcap/tidb/planner/core/assertStaleReadForOptimizePreparedPlan", "return"))
-	require.NoError(t, failpoint.Enable("github.com/pingcap/tidb/executor/assertNotStaleReadForExecutorGetReadTS", "return"))
 	return func() {
 		require.NoError(t, failpoint.Disable("github.com/pingcap/tidb/executor/assertStaleReadValuesSameWithExecuteAndBuilder"))
-		require.NoError(t, failpoint.Disable("github.com/pingcap/tidb/executor/assertNotStaleReadForExecutorGetReadTS"))
 		require.NoError(t, failpoint.Disable("github.com/pingcap/tidb/planner/core/assertStaleReadForOptimizePreparedPlan"))
 	}
 }

session/BUILD.bazel

@@ -49,7 +49,6 @@ go_library(
         "//sessionctx/variable",
         "//sessiontxn",
         "//sessiontxn/isolation",
-        "//sessiontxn/legacy",
         "//sessiontxn/staleread",
         "//statistics",
         "//statistics/handle",

session/session.go

@@ -49,7 +49,6 @@ import (
 	"github.com/pingcap/tidb/parser/terror"
 	"github.com/pingcap/tidb/sessionctx/sessionstates"
 	"github.com/pingcap/tidb/sessiontxn"
-	"github.com/pingcap/tidb/sessiontxn/legacy"
 	"github.com/pingcap/tidb/sessiontxn/staleread"
 	"github.com/pingcap/tidb/store/driver/txn"
 	"github.com/pingcap/tidb/store/helper"
@@ -2385,7 +2384,6 @@ func (s *session) ExecutePreparedStmt(ctx context.Context, stmtID uint32, args [
 		return nil, errors.Errorf("invalid CachedPrepareStmt type")
 	}
 
-	var is infoschema.InfoSchema
 	var snapshotTS uint64
 	replicaReadScope := oracle.GlobalTxnScope
 
@@ -2397,7 +2395,7 @@ func (s *session) ExecutePreparedStmt(ctx context.Context, stmtID uint32, args [
 	txnManager := sessiontxn.GetTxnManager(s)
 	if staleReadProcessor.IsStaleness() {
 		snapshotTS = staleReadProcessor.GetStalenessReadTS()
-		is = staleReadProcessor.GetStalenessInfoSchema()
+		is := staleReadProcessor.GetStalenessInfoSchema()
 		replicaReadScope = config.GetTxnScopeFromConfig()
 		err = txnManager.EnterNewTxn(ctx, &sessiontxn.EnterNewTxnRequest{
 			Type:     sessiontxn.EnterNewTxnWithReplaceProvider,
@@ -2407,8 +2405,6 @@ func (s *session) ExecutePreparedStmt(ctx context.Context, stmtID uint32, args [
 		if err != nil {
 			return nil, err
 		}
-	} else {
-		is = s.GetInfoSchema().(infoschema.InfoSchema)
 	}
 
 	staleness := snapshotTS > 0
@@ -2424,10 +2420,6 @@ func (s *session) ExecutePreparedStmt(ctx context.Context, stmtID uint32, args [
 		return nil, err
 	}
 
-	if p, isOK := txnManager.GetContextProvider().(*legacy.SimpleTxnContextProvider); isOK {
-		p.InfoSchema = is
-	}
-
 	if ok {
 		rs, ok, err := s.cachedPointPlanExec(ctx, txnManager.GetTxnInfoSchema(), stmtID, preparedStmt, replicaReadScope, args)
 		if err != nil {