only forbid Call* at expensive forks

chain/stmgr/call.go

@@ -18,7 +18,7 @@ import (
 	"github.com/filecoin-project/lotus/chain/vm"
 )
 
-var ErrWouldFork = errors.New("refusing explicit call due to state fork at epoch")
+var ErrExpensiveFork = errors.New("refusing explicit call due to state fork at epoch")
 
 func (sm *StateManager) Call(ctx context.Context, msg *types.Message, ts *types.TipSet) (*api.InvocResult, error) {
 	ctx, span := trace.StartSpan(ctx, "statemanager.Call")
@@ -29,7 +29,7 @@ func (sm *StateManager) Call(ctx context.Context, msg *types.Message, ts *types.
 		ts = sm.cs.GetHeaviestTipSet()
 
 		// Search back till we find a height with no fork, or we reach the beginning.
-		for ts.Height() > 0 && sm.hasStateFork(ctx, ts.Height()-1) {
+		for ts.Height() > 0 && sm.hasExpensiveFork(ctx, ts.Height()-1) {
 			var err error
 			ts, err = sm.cs.GetTipSetFromKey(ts.Parents())
 			if err != nil {
@@ -41,14 +41,15 @@ func (sm *StateManager) Call(ctx context.Context, msg *types.Message, ts *types.
 	bstate := ts.ParentState()
 	bheight := ts.Height()
 
-	// If we have to run a migration, and we're not at genesis, return an
-	// error because the migration will take too long.
+	// If we have to run an expensive migration, and we're not at genesis,
+	// return an error because the migration will take too long.
 	//
 	// We allow this at height 0 for at-genesis migrations (for testing).
-	if bheight-1 > 0 && sm.hasStateFork(ctx, bheight-1) {
-		return nil, ErrWouldFork
+	if bheight-1 > 0 && sm.hasExpensiveFork(ctx, bheight-1) {
+		return nil, ErrExpensiveFork
 	}
 
+	// Run the (not expensive) migration.
 	bstate, err := sm.handleStateForks(ctx, bstate, bheight-1, nil, ts)
 	if err != nil {
 		return nil, fmt.Errorf("failed to handle fork: %w", err)
@@ -133,7 +134,7 @@ func (sm *StateManager) CallWithGas(ctx context.Context, msg *types.Message, pri
 		// run the fork logic in `sm.TipSetState`. We need the _current_
 		// height to have no fork, because we'll run it inside this
 		// function before executing the given message.
-		for ts.Height() > 0 && (sm.hasStateFork(ctx, ts.Height()) || sm.hasStateFork(ctx, ts.Height()-1)) {
+		for ts.Height() > 0 && (sm.hasExpensiveFork(ctx, ts.Height()) || sm.hasExpensiveFork(ctx, ts.Height()-1)) {
 			var err error
 			ts, err = sm.cs.GetTipSetFromKey(ts.Parents())
 			if err != nil {
@@ -142,9 +143,9 @@ func (sm *StateManager) CallWithGas(ctx context.Context, msg *types.Message, pri
 		}
 	}
 
-	// When we're not at the genesis block, make sure we're at a migration height.
-	if ts.Height() > 0 && (sm.hasStateFork(ctx, ts.Height()) || sm.hasStateFork(ctx, ts.Height()-1)) {
-		return nil, ErrWouldFork
+	// When we're not at the genesis block, make sure we don't have an expensive migration.
+	if ts.Height() > 0 && (sm.hasExpensiveFork(ctx, ts.Height()) || sm.hasExpensiveFork(ctx, ts.Height()-1)) {
+		return nil, ErrExpensiveFork
 	}
 
 	state, _, err := sm.TipSetState(ctx, ts)

chain/stmgr/forks.go

@@ -45,6 +45,7 @@ type UpgradeFunc func(ctx context.Context, sm *StateManager, cb ExecCallback, ol
 type Upgrade struct {
 	Height    abi.ChainEpoch
 	Network   network.Version
+	Expensive bool
 	Migration UpgradeFunc
 }
 
@@ -68,6 +69,7 @@ func DefaultUpgradeSchedule() UpgradeSchedule {
 	}, {
 		Height:    build.UpgradeActorsV2Height,
 		Network:   network.Version4,
+		Expensive: true,
 		Migration: UpgradeActorsV2,
 	}, {
 		Height:    build.UpgradeLiftoffHeight,
@@ -124,8 +126,8 @@ func (sm *StateManager) handleStateForks(ctx context.Context, root cid.Cid, heig
 	return retCid, nil
 }
 
-func (sm *StateManager) hasStateFork(ctx context.Context, height abi.ChainEpoch) bool {
-	_, ok := sm.stateMigrations[height]
+func (sm *StateManager) hasExpensiveFork(ctx context.Context, height abi.ChainEpoch) bool {
+	_, ok := sm.expensiveUpgrades[height]
 	return ok
 }
 

chain/stmgr/forks_test.go

@@ -248,6 +248,7 @@ func TestForkRefuseCall(t *testing.T) {
 	sm, err := NewStateManagerWithUpgradeSchedule(
 		cg.ChainStore(), UpgradeSchedule{{
 			Network:   1,
+			Expensive: true,
 			Height:    testForkHeight,
 			Migration: func(ctx context.Context, sm *StateManager, cb ExecCallback,
 				root cid.Cid, height abi.ChainEpoch, ts *types.TipSet) (cid.Cid, error) {
@@ -297,7 +298,7 @@ func TestForkRefuseCall(t *testing.T) {
 		switch ts.TipSet.TipSet().Height() {
 		case testForkHeight, testForkHeight + 1:
 			// If I had a fork, or I _will_ have a fork, it should fail.
-			require.Equal(t, ErrWouldFork, err)
+			require.Equal(t, ErrExpensiveFork, err)
 		default:
 			require.NoError(t, err)
 			require.True(t, ret.MsgRct.ExitCode.IsSuccess())
@@ -307,7 +308,7 @@ func TestForkRefuseCall(t *testing.T) {
 		ret, err = sm.Call(ctx, m, ts.TipSet.TipSet())
 		switch ts.TipSet.TipSet().Height() {
 		case testForkHeight + 1:
-			require.Equal(t, ErrWouldFork, err)
+			require.Equal(t, ErrExpensiveFork, err)
 		default:
 			require.NoError(t, err)
 			require.True(t, ret.MsgRct.ExitCode.IsSuccess())

chain/stmgr/stmgr.go

@@ -53,6 +53,10 @@ type StateManager struct {
 
 	// Maps chain epochs to upgrade functions.
 	stateMigrations map[abi.ChainEpoch]UpgradeFunc
+	// A set of potentially expensive/time consuming upgrades. Explicit
+	// calls for, e.g., gas estimation fail against this epoch with
+	// ErrExpensiveFork.
+	expensiveUpgrades map[abi.ChainEpoch]struct{}
 
 	stCache              map[string][]cid.Cid
 	compWait             map[string]chan struct{}
@@ -78,6 +82,7 @@ func NewStateManagerWithUpgradeSchedule(cs *store.ChainStore, us UpgradeSchedule
 	}
 
 	stateMigrations := make(map[abi.ChainEpoch]UpgradeFunc, len(us))
+	expensiveUpgrades := make(map[abi.ChainEpoch]struct{}, len(us))
 	var networkVersions []versionSpec
 	lastVersion := network.Version0
 	if len(us) > 0 {
@@ -87,6 +92,9 @@ func NewStateManagerWithUpgradeSchedule(cs *store.ChainStore, us UpgradeSchedule
 			if upgrade.Migration != nil {
 				stateMigrations[upgrade.Height] = upgrade.Migration
 			}
+			if upgrade.Expensive {
+				expensiveUpgrades[upgrade.Height] = struct{}{}
+			}
 			networkVersions = append(networkVersions, versionSpec{
 				networkVersion: lastVersion,
 				atOrBelow:      upgrade.Height,
@@ -102,6 +110,7 @@ func NewStateManagerWithUpgradeSchedule(cs *store.ChainStore, us UpgradeSchedule
 		networkVersions:   networkVersions,
 		latestVersion:     lastVersion,
 		stateMigrations:   stateMigrations,
+		expensiveUpgrades: expensiveUpgrades,
 		newVM:             vm.NewVM,
 		cs:                cs,
 		stCache:           make(map[string][]cid.Cid),

node/impl/full/gas.go

@@ -164,7 +164,7 @@ func (a *GasAPI) GasEstimateGasLimit(ctx context.Context, msgIn *types.Message,
 	var res *api.InvocResult
 	for {
 		res, err = a.Stmgr.CallWithGas(ctx, &msg, priorMsgs, ts)
-		if err != stmgr.ErrWouldFork {
+		if err != stmgr.ErrExpensiveFork {
 			break
 		}
 		ts, err = a.Chain.GetTipSetFromKey(ts.Parents())

node/impl/full/state.go

@@ -314,7 +314,7 @@ func (a *StateAPI) StateCall(ctx context.Context, msg *types.Message, tsk types.
 	}
 	for {
 		res, err = a.StateManager.Call(ctx, msg, ts)
-		if err != stmgr.ErrWouldFork {
+		if err != stmgr.ErrExpensiveFork {
 			break
 		}
 		ts, err = a.Chain.GetTipSetFromKey(ts.Parents())