Revert "tidb, variable: refactor retry, add TransactionContext" (ping…

…cap#2255)

executor/builder.go

@@ -133,7 +133,6 @@ func (b *executorBuilder) buildCheckTable(v *plan.CheckTable) Executor {
 	return &CheckTableExec{
 		tables: v.Tables,
 		ctx:    b.ctx,
-		is:     b.is,
 	}
 }
 
@@ -221,7 +220,7 @@ func (b *executorBuilder) buildSimple(v *plan.Simple) Executor {
 	case *ast.GrantStmt:
 		return b.buildGrant(s)
 	}
-	return &SimpleExec{Statement: v.Statement, ctx: b.ctx, is: b.is}
+	return &SimpleExec{Statement: v.Statement, ctx: b.ctx}
 }
 
 func (b *executorBuilder) buildSet(v *plan.Set) Executor {
@@ -306,7 +305,6 @@ func (b *executorBuilder) buildGrant(grant *ast.GrantStmt) Executor {
 		ObjectType: grant.ObjectType,
 		Level:      grant.Level,
 		Users:      grant.Users,
-		is:         b.is,
 	}
 }
 

executor/compiler.go

@@ -20,6 +20,8 @@ import (
 	"github.com/pingcap/tidb/context"
 	"github.com/pingcap/tidb/infoschema"
 	"github.com/pingcap/tidb/plan"
+	"github.com/pingcap/tidb/sessionctx"
+	"github.com/pingcap/tidb/sessionctx/binloginfo"
 )
 
 // Compiler compiles an ast.StmtNode to a stmt.Statement.
@@ -152,7 +154,15 @@ func getSelectStmtLabel(x *ast.SelectStmt) string {
 // then wrappped to an adapter *statement as stmt.Statement.
 func (c *Compiler) Compile(ctx context.Context, node ast.StmtNode) (ast.Statement, error) {
 	stmtCount(node)
-	is := GetInfoSchema(ctx)
+	var is infoschema.InfoSchema
+	sessVar := ctx.GetSessionVars()
+	if snap := sessVar.SnapshotInfoschema; snap != nil {
+		is = snap.(infoschema.InfoSchema)
+		log.Infof("[%d] use snapshot schema %d", sessVar.ConnectionID, is.SchemaMetaVersion())
+	} else {
+		is = sessionctx.GetDomain(ctx).InfoSchema()
+		binloginfo.SetSchemaVersion(ctx, is.SchemaMetaVersion())
+	}
 	if err := plan.Preprocess(node, is, ctx); err != nil {
 		return nil, errors.Trace(err)
 	}
@@ -173,17 +183,3 @@ func (c *Compiler) Compile(ctx context.Context, node ast.StmtNode) (ast.Statemen
 	}
 	return sa, nil
 }
-
-// GetInfoSchema gets TxnCtx InfoSchema if snapshot schema is not set,
-// Otherwise, snapshot schema is returned.
-func GetInfoSchema(ctx context.Context) infoschema.InfoSchema {
-	sessVar := ctx.GetSessionVars()
-	var is infoschema.InfoSchema
-	if snap := sessVar.SnapshotInfoschema; snap != nil {
-		is = snap.(infoschema.InfoSchema)
-		log.Infof("[%d] use snapshot schema %d", sessVar.ConnectionID, is.SchemaMetaVersion())
-	} else {
-		is = sessVar.TxnCtx.InfoSchema.(infoschema.InfoSchema)
-	}
-	return is
-}

executor/executor.go

@@ -29,6 +29,8 @@ import (
 	"github.com/pingcap/tidb/model"
 	"github.com/pingcap/tidb/mysql"
 	"github.com/pingcap/tidb/plan"
+	"github.com/pingcap/tidb/sessionctx"
+	"github.com/pingcap/tidb/sessionctx/forupdate"
 	"github.com/pingcap/tidb/sessionctx/variable"
 	"github.com/pingcap/tidb/table"
 	"github.com/pingcap/tidb/tablecodec"
@@ -188,7 +190,6 @@ type CheckTableExec struct {
 	tables []*ast.TableName
 	ctx    context.Context
 	done   bool
-	is     infoschema.InfoSchema
 }
 
 // Schema implements the Executor Schema interface.
@@ -203,9 +204,10 @@ func (e *CheckTableExec) Next() (*Row, error) {
 	}
 
 	dbName := model.NewCIStr(e.ctx.GetSessionVars().CurrentDB)
+	is := sessionctx.GetDomain(e.ctx).InfoSchema()
 
 	for _, t := range e.tables {
-		tb, err := e.is.TableByName(dbName, t.Name)
+		tb, err := is.TableByName(dbName, t.Name)
 		if err != nil {
 			return nil, errors.Trace(err)
 		}
@@ -258,7 +260,7 @@ func (e *SelectLockExec) Next() (*Row, error) {
 		return nil, nil
 	}
 	if len(row.RowKeys) != 0 && e.Lock == ast.SelectLockForUpdate {
-		e.ctx.GetSessionVars().TxnCtx.ForUpdate = true
+		forupdate.SetForUpdate(e.ctx)
 		txn, err := e.ctx.GetTxn(false)
 		if err != nil {
 			return nil, errors.Trace(err)

executor/executor_simple.go

@@ -28,6 +28,7 @@ import (
 	"github.com/pingcap/tidb/model"
 	"github.com/pingcap/tidb/mysql"
 	"github.com/pingcap/tidb/plan/statistics"
+	"github.com/pingcap/tidb/sessionctx"
 	"github.com/pingcap/tidb/sessionctx/variable"
 	"github.com/pingcap/tidb/terror"
 	"github.com/pingcap/tidb/util"
@@ -44,7 +45,6 @@ type SimpleExec struct {
 	Statement ast.StmtNode
 	ctx       context.Context
 	done      bool
-	is        infoschema.InfoSchema
 }
 
 // Schema implements the Executor Schema interface.
@@ -97,7 +97,7 @@ func (e *SimpleExec) Close() error {
 
 func (e *SimpleExec) executeUse(s *ast.UseStmt) error {
 	dbname := model.NewCIStr(s.DBName)
-	dbinfo, exists := e.is.SchemaByName(dbname)
+	dbinfo, exists := sessionctx.GetDomain(e.ctx).InfoSchema().SchemaByName(dbname)
 	if !exists {
 		return infoschema.ErrDatabaseNotExists.GenByArgs(dbname)
 	}

executor/executor_test.go

@@ -1400,7 +1400,6 @@ func (s *testSuite) TestAdapterStatement(c *C) {
 	c.Check(err, IsNil)
 	compiler := &executor.Compiler{}
 	ctx := se.(context.Context)
-	tidb.PrepareTxnCtx(ctx)
 
 	stmtNode, err := s.ParseOneStmt("select 1", "", "")
 	c.Check(err, IsNil)

executor/grant.go

@@ -21,9 +21,9 @@ import (
 	"github.com/pingcap/tidb/ast"
 	"github.com/pingcap/tidb/context"
 	"github.com/pingcap/tidb/expression"
-	"github.com/pingcap/tidb/infoschema"
 	"github.com/pingcap/tidb/model"
 	"github.com/pingcap/tidb/mysql"
+	"github.com/pingcap/tidb/sessionctx"
 	"github.com/pingcap/tidb/table"
 	"github.com/pingcap/tidb/util/sqlexec"
 	"github.com/pingcap/tidb/util/types"
@@ -45,7 +45,6 @@ type GrantExec struct {
 	Users      []*ast.UserSpec
 
 	ctx  context.Context
-	is   infoschema.InfoSchema
 	done bool
 }
 
@@ -495,7 +494,8 @@ func (e *GrantExec) getTargetSchema() (*model.DBInfo, error) {
 	}
 	//check if db exists
 	schema := model.NewCIStr(dbName)
-	db, ok := e.is.SchemaByName(schema)
+	is := sessionctx.GetDomain(e.ctx).InfoSchema()
+	db, ok := is.SchemaByName(schema)
 	if !ok {
 		return nil, errors.Errorf("Unknown schema name: %s", dbName)
 	}
@@ -509,7 +509,8 @@ func (e *GrantExec) getTargetSchemaAndTable() (*model.DBInfo, table.Table, error
 		return nil, nil, errors.Trace(err)
 	}
 	name := model.NewCIStr(e.Level.TableName)
-	tbl, err := e.is.TableByName(db.Name, name)
+	is := sessionctx.GetDomain(e.ctx).InfoSchema()
+	tbl, err := is.TableByName(db.Name, name)
 	if err != nil {
 		return nil, nil, errors.Trace(err)
 	}

executor/prepared.go

@@ -23,6 +23,7 @@ import (
 	"github.com/pingcap/tidb/infoschema"
 	"github.com/pingcap/tidb/parser"
 	"github.com/pingcap/tidb/plan"
+	"github.com/pingcap/tidb/sessionctx"
 	"github.com/pingcap/tidb/util/sqlexec"
 )
 
@@ -282,7 +283,7 @@ func CompileExecutePreparedStmt(ctx context.Context, ID uint32, args ...interfac
 		execPlan.UsingVars[i] = &expression.Constant{Value: value.Datum, RetType: &value.Type}
 	}
 	sa := &statement{
-		is:   GetInfoSchema(ctx),
+		is:   sessionctx.GetDomain(ctx).InfoSchema(),
 		plan: execPlan,
 	}
 	return sa

executor/union_scan.go

@@ -72,12 +72,21 @@ type dirtyTable struct {
 	truncated   bool
 }
 
+type dirtyDBKeyType int
+
+func (u dirtyDBKeyType) String() string {
+	return "dirtyDBKeyType"
+}
+
+// DirtyDBKey is the key to *dirtyDB for a context.
+const DirtyDBKey dirtyDBKeyType = 1
+
 func getDirtyDB(ctx context.Context) *dirtyDB {
 	var udb *dirtyDB
-	x := ctx.GetSessionVars().TxnCtx.DirtyDB
+	x := ctx.Value(DirtyDBKey)
 	if x == nil {
 		udb = &dirtyDB{tables: make(map[int64]*dirtyTable)}
-		ctx.GetSessionVars().TxnCtx.DirtyDB = udb
+		ctx.SetValue(DirtyDBKey, udb)
 	} else {
 		udb = x.(*dirtyDB)
 	}

kv/kv.go

@@ -27,6 +27,8 @@ const (
 	// PresumeKeyNotExistsError is the option key for error.
 	// When PresumeKeyNotExists is set and condition is not match, should throw the error.
 	PresumeKeyNotExistsError
+	// RetryAttempts is the number of txn retry attempt.
+	RetryAttempts
 	// BinlogData is the binlog data to write.
 	BinlogData
 )