operator: allows to skip placement rules checks (#5458)

close #5401

Signed-off-by: HunDunDM <hundundm@gmail.com>

server/schedule/operator/builder.go

@@ -67,8 +67,9 @@ type Builder struct {
 	targetLeaderStoreIDs []uint64 // This field is only used during multi-target evict leader, and will not be filtered during `Build`.
 	err                  error
 
-	// skip origin check flags
+	// skip check flags
 	skipOriginJointStateCheck bool
+	skipPlacementRulesCheck   bool
 
 	// build flags
 	useJointConsensus bool
@@ -94,6 +95,11 @@ func SkipOriginJointStateCheck(b *Builder) {
 	b.skipOriginJointStateCheck = true
 }
 
+// SkipPlacementRulesCheck lets the builder skip the placement rules check for origin and target peers.
+func SkipPlacementRulesCheck(b *Builder) {
+	b.skipPlacementRulesCheck = true
+}
+
 // NewBuilder creates a Builder.
 func NewBuilder(desc string, ci ClusterInformer, region *core.RegionInfo, opts ...BuilderOption) *Builder {
 	b := &Builder{
@@ -138,7 +144,7 @@ func NewBuilder(desc string, ci ClusterInformer, region *core.RegionInfo, opts .
 
 	// placement rules
 	var rules []*placement.Rule
-	if err == nil && b.GetOpts().IsPlacementRulesEnabled() {
+	if err == nil && !b.skipPlacementRulesCheck && b.GetOpts().IsPlacementRulesEnabled() {
 		fit := b.GetRuleManager().FitRegion(b.GetBasicCluster(), region)
 		for _, rf := range fit.RuleFits {
 			rules = append(rules, rf.Rule)
@@ -775,7 +781,7 @@ func (b *Builder) allowLeader(peer *metapb.Peer, ignoreClusterLimit bool) bool {
 	}
 
 	// placement rules
-	if len(b.rules) == 0 {
+	if b.skipPlacementRulesCheck || len(b.rules) == 0 {
 		return true
 	}
 	for _, r := range b.rules {

server/schedule/operator/create_operator.go

@@ -67,7 +67,7 @@ func CreateTransferLeaderOperator(desc string, ci ClusterInformer, region *core.
 
 // CreateForceTransferLeaderOperator creates an operator that transfers the leader from a source store to a target store forcible.
 func CreateForceTransferLeaderOperator(desc string, ci ClusterInformer, region *core.RegionInfo, sourceStoreID uint64, targetStoreID uint64, kind OpKind) (*Operator, error) {
-	return NewBuilder(desc, ci, region, SkipOriginJointStateCheck).
+	return NewBuilder(desc, ci, region, SkipOriginJointStateCheck, SkipPlacementRulesCheck).
 		SetLeader(targetStoreID).
 		EnableForceTargetLeader().
 		Build(kind)
@@ -225,7 +225,7 @@ const OpDescLeaveJointState = "leave-joint-state"
 
 // CreateLeaveJointStateOperator creates an operator that let region leave joint state.
 func CreateLeaveJointStateOperator(desc string, ci ClusterInformer, origin *core.RegionInfo) (*Operator, error) {
-	b := NewBuilder(desc, ci, origin, SkipOriginJointStateCheck)
+	b := NewBuilder(desc, ci, origin, SkipOriginJointStateCheck, SkipPlacementRulesCheck)
 
 	if b.err == nil && !core.IsInJointState(origin.GetPeers()...) {
 		b.err = errors.Errorf("cannot build leave joint state operator for region which is not in joint state")

server/schedule/operator/create_operator_test.go

@@ -16,11 +16,13 @@ package operator
 
 import (
 	"context"
+	"encoding/hex"
 	"testing"
 
 	"github.com/pingcap/errors"
 	"github.com/pingcap/kvproto/pkg/metapb"
 	"github.com/pingcap/kvproto/pkg/pdpb"
+	"github.com/stretchr/testify/require"
 	"github.com/stretchr/testify/suite"
 	"github.com/tikv/pd/pkg/mock/mockcluster"
 	"github.com/tikv/pd/server/config"
@@ -1078,3 +1080,61 @@ func (suite *createOperatorTestSuite) TestMoveRegionWithoutJointConsensus() {
 		}
 	}
 }
+
+// Ref https://github.com/tikv/pd/issues/5401
+func TestCreateLeaveJointStateOperatorWithoutFitRules(t *testing.T) {
+	re := require.New(t)
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	opts := config.NewTestOptions()
+	cluster := mockcluster.NewCluster(ctx, opts)
+	re.NoError(cluster.SetRules([]*placement.Rule{
+		{
+			GroupID:     "pd",
+			ID:          "default",
+			StartKeyHex: hex.EncodeToString([]byte("")),
+			EndKeyHex:   hex.EncodeToString([]byte("")),
+			Role:        placement.Voter,
+			Count:       1,
+		},
+		{
+			GroupID:     "t1",
+			ID:          "t1",
+			StartKeyHex: hex.EncodeToString([]byte("a")),
+			EndKeyHex:   hex.EncodeToString([]byte("b")),
+			Role:        placement.Voter,
+			Count:       1,
+		},
+		{
+			GroupID:     "t2",
+			ID:          "t2",
+			StartKeyHex: hex.EncodeToString([]byte("b")),
+			EndKeyHex:   hex.EncodeToString([]byte("c")),
+			Role:        placement.Voter,
+			Count:       1,
+		},
+	}))
+	cluster.AddRegionStore(1, 1)
+	cluster.AddRegionStore(2, 1)
+	cluster.AddRegionStore(3, 1)
+	cluster.AddRegionStore(4, 1)
+	originPeers := []*metapb.Peer{
+		{Id: 3, StoreId: 3, Role: metapb.PeerRole_DemotingVoter},
+		{Id: 4, StoreId: 4, Role: metapb.PeerRole_IncomingVoter},
+	}
+
+	region := core.NewRegionInfo(&metapb.Region{Id: 1, Peers: originPeers, StartKey: []byte("a"), EndKey: []byte("c")}, originPeers[0])
+	op, err := CreateLeaveJointStateOperator("test", cluster, region)
+	re.NoError(err)
+	re.Equal(OpLeader, op.Kind())
+	re.Len(op.steps, 2)
+	step0 := op.steps[0].(TransferLeader)
+	re.Equal(uint64(3), step0.FromStore)
+	re.Equal(uint64(4), step0.ToStore)
+	step1 := op.steps[1].(ChangePeerV2Leave)
+	re.Len(step1.PromoteLearners, 1)
+	re.Len(step1.DemoteVoters, 1)
+	re.Equal(uint64(4), step1.PromoteLearners[0].ToStore)
+	re.Equal(uint64(3), step1.DemoteVoters[0].ToStore)
+}