store/tikv: resolve ReplicaReadType dependencies

distsql/request_builder_test.go

@@ -25,7 +25,6 @@ import (
 	"github.com/pingcap/tidb/sessionctx/stmtctx"
 	"github.com/pingcap/tidb/sessionctx/variable"
 	"github.com/pingcap/tidb/statistics"
-	tikvstore "github.com/pingcap/tidb/store/tikv/kv"
 	"github.com/pingcap/tidb/tablecodec"
 	"github.com/pingcap/tidb/types"
 	"github.com/pingcap/tidb/util/chunk"
@@ -324,7 +323,7 @@ func (s *testSuite) TestRequestBuilder1(c *C) {
 		NotFillCache:   false,
 		SyncLog:        false,
 		Streaming:      false,
-		ReplicaRead:    tikvstore.ReplicaReadLeader,
+		ReplicaRead:    kv.ReplicaReadLeader,
 	}
 	c.Assert(actual, DeepEquals, expect)
 }
@@ -400,7 +399,7 @@ func (s *testSuite) TestRequestBuilder2(c *C) {
 		NotFillCache:   false,
 		SyncLog:        false,
 		Streaming:      false,
-		ReplicaRead:    tikvstore.ReplicaReadLeader,
+		ReplicaRead:    kv.ReplicaReadLeader,
 	}
 	c.Assert(actual, DeepEquals, expect)
 }
@@ -447,7 +446,7 @@ func (s *testSuite) TestRequestBuilder3(c *C) {
 		NotFillCache:   false,
 		SyncLog:        false,
 		Streaming:      false,
-		ReplicaRead:    tikvstore.ReplicaReadLeader,
+		ReplicaRead:    kv.ReplicaReadLeader,
 	}
 	c.Assert(actual, DeepEquals, expect)
 }
@@ -494,7 +493,7 @@ func (s *testSuite) TestRequestBuilder4(c *C) {
 		Streaming:      true,
 		NotFillCache:   false,
 		SyncLog:        false,
-		ReplicaRead:    tikvstore.ReplicaReadLeader,
+		ReplicaRead:    kv.ReplicaReadLeader,
 	}
 	c.Assert(actual, DeepEquals, expect)
 }
@@ -577,10 +576,10 @@ func (s *testSuite) TestRequestBuilder6(c *C) {
 }
 
 func (s *testSuite) TestRequestBuilder7(c *C) {
-	for _, replicaRead := range []tikvstore.ReplicaReadType{
-		tikvstore.ReplicaReadLeader,
-		tikvstore.ReplicaReadFollower,
-		tikvstore.ReplicaReadMixed,
+	for _, replicaRead := range []kv.ReplicaReadType{
+		kv.ReplicaReadLeader,
+		kv.ReplicaReadFollower,
+		kv.ReplicaReadMixed,
 	} {
 		vars := variable.NewSessionVars()
 		vars.SetReplicaRead(replicaRead)

executor/analyze.go

@@ -45,7 +45,6 @@ import (
 	"github.com/pingcap/tidb/sessionctx/variable"
 	"github.com/pingcap/tidb/statistics"
 	"github.com/pingcap/tidb/store/tikv"
-	tikvstore "github.com/pingcap/tidb/store/tikv/kv"
 	"github.com/pingcap/tidb/table"
 	"github.com/pingcap/tidb/tablecodec"
 	"github.com/pingcap/tidb/types"
@@ -1322,7 +1321,7 @@ func (e *AnalyzeFastExec) handleScanIter(iter kv.Iterator) (scanKeysSize int, er
 func (e *AnalyzeFastExec) handleScanTasks(bo *tikv.Backoffer) (keysSize int, err error) {
 	snapshot := e.ctx.GetStore().GetSnapshot(kv.MaxVersion)
 	if e.ctx.GetSessionVars().GetReplicaRead().IsFollowerRead() {
-		snapshot.SetOption(kv.ReplicaRead, tikvstore.ReplicaReadFollower)
+		snapshot.SetOption(kv.ReplicaRead, kv.ReplicaReadFollower)
 	}
 	for _, t := range e.scanTasks {
 		iter, err := snapshot.Iter(kv.Key(t.StartKey), kv.Key(t.EndKey))
@@ -1345,7 +1344,7 @@ func (e *AnalyzeFastExec) handleSampTasks(workID int, step uint32, err *error) {
 	snapshot.SetOption(kv.IsolationLevel, kv.RC)
 	snapshot.SetOption(kv.Priority, kv.PriorityLow)
 	if e.ctx.GetSessionVars().GetReplicaRead().IsFollowerRead() {
-		snapshot.SetOption(kv.ReplicaRead, tikvstore.ReplicaReadFollower)
+		snapshot.SetOption(kv.ReplicaRead, kv.ReplicaReadFollower)
 	}
 
 	rander := rand.New(rand.NewSource(e.randSeed))

executor/analyze_test.go

@@ -29,6 +29,7 @@ import (
 	"github.com/pingcap/tidb/domain"
 	"github.com/pingcap/tidb/executor"
 	"github.com/pingcap/tidb/infoschema"
+	"github.com/pingcap/tidb/kv"
 	"github.com/pingcap/tidb/planner/core"
 	"github.com/pingcap/tidb/session"
 	"github.com/pingcap/tidb/sessionctx"
@@ -38,7 +39,6 @@ import (
 	"github.com/pingcap/tidb/statistics/handle"
 	"github.com/pingcap/tidb/store/mockstore"
 	"github.com/pingcap/tidb/store/tikv"
-	tikvstore "github.com/pingcap/tidb/store/tikv/kv"
 	"github.com/pingcap/tidb/store/tikv/mockstore/cluster"
 	"github.com/pingcap/tidb/store/tikv/tikvrpc"
 	"github.com/pingcap/tidb/table"
@@ -121,7 +121,7 @@ func (s *testSuite1) TestAnalyzeReplicaReadFollower(c *C) {
 	tk.MustExec("drop table if exists t")
 	tk.MustExec("create table t(a int)")
 	ctx := tk.Se.(sessionctx.Context)
-	ctx.GetSessionVars().SetReplicaRead(tikvstore.ReplicaReadFollower)
+	ctx.GetSessionVars().SetReplicaRead(kv.ReplicaReadFollower)
 	tk.MustExec("analyze table t")
 }
 

executor/batch_point_get.go

@@ -117,7 +117,7 @@ func (e *BatchPointGetExec) Open(context.Context) error {
 		e.ctx.GetSessionVars().StmtCtx.RuntimeStatsColl.RegisterStats(e.id, e.stats)
 	}
 	if e.ctx.GetSessionVars().GetReplicaRead().IsFollowerRead() {
-		snapshot.SetOption(kv.ReplicaRead, tikvstore.ReplicaReadFollower)
+		snapshot.SetOption(kv.ReplicaRead, kv.ReplicaReadFollower)
 	}
 	snapshot.SetOption(kv.TaskID, e.ctx.GetSessionVars().StmtCtx.TaskID)
 	isStaleness := e.ctx.GetSessionVars().TxnCtx.IsStaleness

executor/point_get.go

@@ -148,7 +148,7 @@ func (e *PointGetExecutor) Open(context.Context) error {
 		e.ctx.GetSessionVars().StmtCtx.RuntimeStatsColl.RegisterStats(e.id, e.stats)
 	}
 	if e.ctx.GetSessionVars().GetReplicaRead().IsFollowerRead() {
-		e.snapshot.SetOption(kv.ReplicaRead, tikvstore.ReplicaReadFollower)
+		e.snapshot.SetOption(kv.ReplicaRead, kv.ReplicaReadFollower)
 	}
 	e.snapshot.SetOption(kv.TaskID, e.ctx.GetSessionVars().StmtCtx.TaskID)
 	isStaleness := e.ctx.GetSessionVars().TxnCtx.IsStaleness

kv/kv.go

@@ -273,7 +273,7 @@ type Request struct {
 	// call would not corresponds to a whole region result.
 	Streaming bool
 	// ReplicaRead is used for reading data from replicas, only follower is supported at this time.
-	ReplicaRead tikvstore.ReplicaReadType
+	ReplicaRead ReplicaReadType
 	// StoreType represents this request is sent to the which type of store.
 	StoreType StoreType
 	// Cacheable is true if the request can be cached. Currently only deterministic DAG requests can be cached.

kv/option.go

@@ -60,3 +60,20 @@ const (
 	// MatchStoreLabels indicates the labels the store should be matched
 	MatchStoreLabels
 )
+
+// ReplicaReadType is the type of replica to read data from
+type ReplicaReadType byte
+
+const (
+	// ReplicaReadLeader stands for 'read from leader'.
+	ReplicaReadLeader ReplicaReadType = iota
+	// ReplicaReadFollower stands for 'read from follower'.
+	ReplicaReadFollower
+	// ReplicaReadMixed stands for 'read from leader and follower and learner'.
+	ReplicaReadMixed
+)
+
+// IsFollowerRead checks if follower is going to be used to read data.
+func (r ReplicaReadType) IsFollowerRead() bool {
+	return r != ReplicaReadLeader
+}

planner/optimize.go

@@ -36,7 +36,6 @@ import (
 	"github.com/pingcap/tidb/sessionctx"
 	"github.com/pingcap/tidb/sessionctx/stmtctx"
 	"github.com/pingcap/tidb/sessionctx/variable"
-	tikvstore "github.com/pingcap/tidb/store/tikv/kv"
 	"github.com/pingcap/tidb/types"
 	"github.com/pingcap/tidb/util/hint"
 	"github.com/pingcap/tidb/util/logutil"
@@ -533,7 +532,7 @@ func handleStmtHints(hints []*ast.TableOptimizerHint) (stmtHints stmtctx.StmtHin
 			warns = append(warns, warn)
 		}
 		stmtHints.HasReplicaReadHint = true
-		stmtHints.ReplicaRead = byte(tikvstore.ReplicaReadFollower)
+		stmtHints.ReplicaRead = byte(kv.ReplicaReadFollower)
 	}
 	// Handle MAX_EXECUTION_TIME
 	if maxExecutionTimeCnt != 0 {

session/session.go

@@ -69,7 +69,6 @@ import (
 	"github.com/pingcap/tidb/statistics"
 	"github.com/pingcap/tidb/statistics/handle"
 	"github.com/pingcap/tidb/store/tikv"
-	tikvstore "github.com/pingcap/tidb/store/tikv/kv"
 	"github.com/pingcap/tidb/store/tikv/oracle"
 	tikvutil "github.com/pingcap/tidb/store/tikv/util"
 	"github.com/pingcap/tidb/tablecodec"
@@ -1891,7 +1890,7 @@ func (s *session) Txn(active bool) (kv.Transaction, error) {
 		s.sessionVars.TxnCtx.CouldRetry = s.isTxnRetryable()
 		s.txn.SetVars(s.sessionVars.KVVars)
 		if s.sessionVars.GetReplicaRead().IsFollowerRead() {
-			s.txn.SetOption(kv.ReplicaRead, tikvstore.ReplicaReadFollower)
+			s.txn.SetOption(kv.ReplicaRead, kv.ReplicaReadFollower)
 		}
 	}
 	return &s.txn, nil
@@ -1955,7 +1954,7 @@ func (s *session) NewTxn(ctx context.Context) error {
 	}
 	txn.SetVars(s.sessionVars.KVVars)
 	if s.GetSessionVars().GetReplicaRead().IsFollowerRead() {
-		txn.SetOption(kv.ReplicaRead, tikvstore.ReplicaReadFollower)
+		txn.SetOption(kv.ReplicaRead, kv.ReplicaReadFollower)
 	}
 	s.txn.changeInvalidToValid(txn)
 	is := domain.GetDomain(s).InfoSchema()

session/session_test.go

@@ -51,7 +51,6 @@ import (
 	"github.com/pingcap/tidb/store/mockstore"
 	"github.com/pingcap/tidb/store/mockstore/mockcopr"
 	"github.com/pingcap/tidb/store/tikv"
-	tikvstore "github.com/pingcap/tidb/store/tikv/kv"
 	"github.com/pingcap/tidb/store/tikv/mockstore/cluster"
 	"github.com/pingcap/tidb/store/tikv/oracle"
 	tikvutil "github.com/pingcap/tidb/store/tikv/util"
@@ -3064,11 +3063,11 @@ func (s *testSessionSuite2) TestReplicaRead(c *C) {
 	tk := testkit.NewTestKit(c, s.store)
 	tk.Se, err = session.CreateSession4Test(s.store)
 	c.Assert(err, IsNil)
-	c.Assert(tk.Se.GetSessionVars().GetReplicaRead(), Equals, tikvstore.ReplicaReadLeader)
+	c.Assert(tk.Se.GetSessionVars().GetReplicaRead(), Equals, kv.ReplicaReadLeader)
 	tk.MustExec("set @@tidb_replica_read = 'follower';")
-	c.Assert(tk.Se.GetSessionVars().GetReplicaRead(), Equals, tikvstore.ReplicaReadFollower)
+	c.Assert(tk.Se.GetSessionVars().GetReplicaRead(), Equals, kv.ReplicaReadFollower)
 	tk.MustExec("set @@tidb_replica_read = 'leader';")
-	c.Assert(tk.Se.GetSessionVars().GetReplicaRead(), Equals, tikvstore.ReplicaReadLeader)
+	c.Assert(tk.Se.GetSessionVars().GetReplicaRead(), Equals, kv.ReplicaReadLeader)
 }
 
 func (s *testSessionSuite3) TestIsolationRead(c *C) {
@@ -3153,12 +3152,12 @@ func (s *testSessionSuite2) TestStmtHints(c *C) {
 	c.Assert(tk.Se.GetSessionVars().GetEnableCascadesPlanner(), IsTrue)
 
 	// Test READ_CONSISTENT_REPLICA hint
-	tk.Se.GetSessionVars().SetReplicaRead(tikvstore.ReplicaReadLeader)
+	tk.Se.GetSessionVars().SetReplicaRead(kv.ReplicaReadLeader)
 	tk.MustExec("select /*+ READ_CONSISTENT_REPLICA() */ 1;")
-	c.Assert(tk.Se.GetSessionVars().GetReplicaRead(), Equals, tikvstore.ReplicaReadFollower)
+	c.Assert(tk.Se.GetSessionVars().GetReplicaRead(), Equals, kv.ReplicaReadFollower)
 	tk.MustExec("select /*+ READ_CONSISTENT_REPLICA(), READ_CONSISTENT_REPLICA() */ 1;")
 	c.Assert(tk.Se.GetSessionVars().StmtCtx.GetWarnings(), HasLen, 1)
-	c.Assert(tk.Se.GetSessionVars().GetReplicaRead(), Equals, tikvstore.ReplicaReadFollower)
+	c.Assert(tk.Se.GetSessionVars().GetReplicaRead(), Equals, kv.ReplicaReadFollower)
 }
 
 func (s *testSessionSuite3) TestPessimisticLockOnPartition(c *C) {

sessionctx/variable/session.go

@@ -723,7 +723,7 @@ type SessionVars struct {
 	enableIndexMerge bool
 
 	// replicaRead is used for reading data from replicas, only follower is supported at this time.
-	replicaRead tikvstore.ReplicaReadType
+	replicaRead kv.ReplicaReadType
 
 	// IsolationReadEngines is used to isolation read, tidb only read from the stores whose engine type is in the engines.
 	IsolationReadEngines map[kv.StoreType]struct{}
@@ -1029,7 +1029,7 @@ func NewSessionVars() *SessionVars {
 		WaitSplitRegionTimeout:      DefWaitSplitRegionTimeout,
 		enableIndexMerge:            false,
 		EnableNoopFuncs:             DefTiDBEnableNoopFuncs,
-		replicaRead:                 tikvstore.ReplicaReadLeader,
+		replicaRead:                 kv.ReplicaReadLeader,
 		AllowRemoveAutoInc:          DefTiDBAllowRemoveAutoInc,
 		UsePlanBaselines:            DefTiDBUsePlanBaselines,
 		EvolvePlanBaselines:         DefTiDBEvolvePlanBaselines,
@@ -1179,15 +1179,15 @@ func (s *SessionVars) SetEnableIndexMerge(val bool) {
 }
 
 // GetReplicaRead get ReplicaRead from sql hints and SessionVars.replicaRead.
-func (s *SessionVars) GetReplicaRead() tikvstore.ReplicaReadType {
+func (s *SessionVars) GetReplicaRead() kv.ReplicaReadType {
 	if s.StmtCtx.HasReplicaReadHint {
-		return tikvstore.ReplicaReadType(s.StmtCtx.ReplicaRead)
+		return kv.ReplicaReadType(s.StmtCtx.ReplicaRead)
 	}
 	return s.replicaRead
 }
 
 // SetReplicaRead set SessionVars.replicaRead.
-func (s *SessionVars) SetReplicaRead(val tikvstore.ReplicaReadType) {
+func (s *SessionVars) SetReplicaRead(val kv.ReplicaReadType) {
 	s.replicaRead = val
 }
 

sessionctx/variable/sysvar.go

@@ -1246,11 +1246,11 @@ var defaultSysVars = []*SysVar{
 	}},
 	{Scope: ScopeSession, Name: TiDBReplicaRead, Value: "leader", Type: TypeEnum, PossibleValues: []string{"leader", "follower", "leader-and-follower"}, SetSession: func(s *SessionVars, val string) error {
 		if strings.EqualFold(val, "follower") {
-			s.SetReplicaRead(tikvstore.ReplicaReadFollower)
+			s.SetReplicaRead(kv.ReplicaReadFollower)
 		} else if strings.EqualFold(val, "leader-and-follower") {
-			s.SetReplicaRead(tikvstore.ReplicaReadMixed)
+			s.SetReplicaRead(kv.ReplicaReadMixed)
 		} else if strings.EqualFold(val, "leader") || len(val) == 0 {
-			s.SetReplicaRead(tikvstore.ReplicaReadLeader)
+			s.SetReplicaRead(kv.ReplicaReadLeader)
 		}
 		return nil
 	}},

sessionctx/variable/varsutil_test.go

@@ -23,7 +23,7 @@ import (
 	"github.com/pingcap/parser/mysql"
 	"github.com/pingcap/parser/terror"
 	"github.com/pingcap/tidb/config"
-	tikvstore "github.com/pingcap/tidb/store/tikv/kv"
+	"github.com/pingcap/tidb/kv"
 	"github.com/pingcap/tidb/util/testleak"
 )
 
@@ -431,19 +431,19 @@ func (s *testVarsutilSuite) TestVarsutil(c *C) {
 	val, err = GetSessionOrGlobalSystemVar(v, TiDBReplicaRead)
 	c.Assert(err, IsNil)
 	c.Assert(val, Equals, "follower")
-	c.Assert(v.GetReplicaRead(), Equals, tikvstore.ReplicaReadFollower)
+	c.Assert(v.GetReplicaRead(), Equals, kv.ReplicaReadFollower)
 	err = SetSessionSystemVar(v, TiDBReplicaRead, "leader")
 	c.Assert(err, IsNil)
 	val, err = GetSessionOrGlobalSystemVar(v, TiDBReplicaRead)
 	c.Assert(err, IsNil)
 	c.Assert(val, Equals, "leader")
-	c.Assert(v.GetReplicaRead(), Equals, tikvstore.ReplicaReadLeader)
+	c.Assert(v.GetReplicaRead(), Equals, kv.ReplicaReadLeader)
 	err = SetSessionSystemVar(v, TiDBReplicaRead, "leader-and-follower")
 	c.Assert(err, IsNil)
 	val, err = GetSessionOrGlobalSystemVar(v, TiDBReplicaRead)
 	c.Assert(err, IsNil)
 	c.Assert(val, Equals, "leader-and-follower")
-	c.Assert(v.GetReplicaRead(), Equals, tikvstore.ReplicaReadMixed)
+	c.Assert(v.GetReplicaRead(), Equals, kv.ReplicaReadMixed)
 
 	err = SetSessionSystemVar(v, TiDBEnableStmtSummary, "ON")
 	c.Assert(err, IsNil)

store/copr/coprocessor.go

@@ -37,6 +37,7 @@ import (
 	tidbmetrics "github.com/pingcap/tidb/metrics"
 	"github.com/pingcap/tidb/store/driver/backoff"
 	derr "github.com/pingcap/tidb/store/driver/error"
+	"github.com/pingcap/tidb/store/driver/options"
 	"github.com/pingcap/tidb/store/tikv"
 	"github.com/pingcap/tidb/store/tikv/logutil"
 	"github.com/pingcap/tidb/store/tikv/metrics"
@@ -697,7 +698,7 @@ func (worker *copIteratorWorker) handleTaskOnce(bo *Backoffer, task *copTask, ch
 		}
 	}
 
-	req := tikvrpc.NewReplicaReadRequest(task.cmdType, &copReq, worker.req.ReplicaRead, &worker.replicaReadSeed, kvrpcpb.Context{
+	req := tikvrpc.NewReplicaReadRequest(task.cmdType, &copReq, options.GetTiKVReplicaReadType(worker.req.ReplicaRead), &worker.replicaReadSeed, kvrpcpb.Context{
 		IsolationLevel: isolationLevelToPB(worker.req.IsolationLevel),
 		Priority:       priorityToPB(worker.req.Priority),
 		NotFillCache:   worker.req.NotFillCache,

store/driver/options/options.go

@@ -0,0 +1,32 @@
+// Copyright 2021 PingCAP, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package options
+
+import (
+	"github.com/pingcap/tidb/kv"
+	storekv "github.com/pingcap/tidb/store/tikv/kv"
+)
+
+// GetTiKVReplicaReadType maps kv.ReplicaReadType to tikv/kv.ReplicaReadType.
+func GetTiKVReplicaReadType(t kv.ReplicaReadType) storekv.ReplicaReadType {
+	switch t {
+	case kv.ReplicaReadLeader:
+		return storekv.ReplicaReadLeader
+	case kv.ReplicaReadFollower:
+		return storekv.ReplicaReadFollower
+	case kv.ReplicaReadMixed:
+		return storekv.ReplicaReadMixed
+	}
+	return 0
+}

store/driver/txn/snapshot.go

@@ -20,8 +20,8 @@ import (
 	"github.com/pingcap/kvproto/pkg/metapb"
 	"github.com/pingcap/tidb/kv"
 	derr "github.com/pingcap/tidb/store/driver/error"
+	"github.com/pingcap/tidb/store/driver/options"
 	"github.com/pingcap/tidb/store/tikv"
-	tikvstore "github.com/pingcap/tidb/store/tikv/kv"
 )
 
 type tikvSnapshot struct {
@@ -76,7 +76,8 @@ func (s *tikvSnapshot) SetOption(opt int, val interface{}) {
 	case kv.SnapshotTS:
 		s.KVSnapshot.SetSnapshotTS(val.(uint64))
 	case kv.ReplicaRead:
-		s.KVSnapshot.SetReplicaRead(val.(tikvstore.ReplicaReadType))
+		t := options.GetTiKVReplicaReadType(val.(kv.ReplicaReadType))
+		s.KVSnapshot.SetReplicaRead(t)
 	case kv.SampleStep:
 		s.KVSnapshot.SetSampleStep(val.(uint32))
 	case kv.TaskID: