core/state: extend snapshotter to handle account resurrections

core/blockchain.go

@@ -198,6 +198,7 @@ func NewBlockChain(db ethdb.Database, cacheConfig *CacheConfig, chainConfig *par
 			TrieDirtyLimit: 256,
 			TrieTimeLimit:  5 * time.Minute,
 			SnapshotLimit:  256,
+			SnapshotWait:   true,
 		}
 	}
 	bodyCache, _ := lru.New(bodyCacheLimit)

core/blockchain_test.go

@@ -2315,7 +2315,7 @@ func TestDeleteCreateRevert(t *testing.T) {
 				// The address 0xAAAAA selfdestructs if called
 				aa: {
 					// Code needs to just selfdestruct
-					Code:    []byte{byte(vm.PC), 0xFF},
+					Code:    []byte{byte(vm.PC), byte(vm.SELFDESTRUCT)},
 					Nonce:   1,
 					Balance: big.NewInt(0),
 				},
@@ -2383,7 +2383,7 @@ func TestDeleteRecreateSlots(t *testing.T) {
 		aa        = common.HexToAddress("0x7217d81b76bdd8707601e959454e3d776aee5f43")
 		bb        = common.HexToAddress("0x000000000000000000000000000000000000bbbb")
 		aaStorage = make(map[common.Hash]common.Hash)          // Initial storage in AA
-		aaCode    = []byte{byte(vm.PC), 0xFF}         // Code for AA (simple selfdestruct)
+		aaCode    = []byte{byte(vm.PC), byte(vm.SELFDESTRUCT)} // Code for AA (simple selfdestruct)
 	)
 	// Populate two slots
 	aaStorage[common.HexToHash("01")] = common.HexToHash("01")
@@ -2507,7 +2507,7 @@ func TestDeleteRecreateAccount(t *testing.T) {
 
 		aa        = common.HexToAddress("0x7217d81b76bdd8707601e959454e3d776aee5f43")
 		aaStorage = make(map[common.Hash]common.Hash)          // Initial storage in AA
-		aaCode    = []byte{byte(vm.PC), 0xFF}         // Code for AA (simple selfdestruct)
+		aaCode    = []byte{byte(vm.PC), byte(vm.SELFDESTRUCT)} // Code for AA (simple selfdestruct)
 	)
 	// Populate two slots
 	aaStorage[common.HexToHash("01")] = common.HexToHash("01")

core/state/snapshot/disklayer.go

@@ -161,6 +161,6 @@ func (dl *diskLayer) Storage(accountHash, storageHash common.Hash) ([]byte, erro
 // Update creates a new layer on top of the existing snapshot diff tree with
 // the specified data items. Note, the maps are retained by the method to avoid
 // copying everything.
-func (dl *diskLayer) Update(blockHash common.Hash, accounts map[common.Hash][]byte, storage map[common.Hash]map[common.Hash][]byte) *diffLayer {
-	return newDiffLayer(dl, blockHash, accounts, storage)
+func (dl *diskLayer) Update(blockHash common.Hash, destructs map[common.Hash]struct{}, accounts map[common.Hash][]byte, storage map[common.Hash]map[common.Hash][]byte) *diffLayer {
+	return newDiffLayer(dl, blockHash, destructs, accounts, storage)
 }

core/state/snapshot/disklayer_test.go

@@ -116,13 +116,14 @@ func TestDiskMerge(t *testing.T) {
 	base.Storage(conNukeCache, conNukeCacheSlot)
 
 	// Modify or delete some accounts, flatten everything onto disk
-	if err := snaps.Update(diffRoot, baseRoot, map[common.Hash][]byte{
+	if err := snaps.Update(diffRoot, baseRoot, map[common.Hash]struct{}{
+		accDelNoCache:  struct{}{},
+		accDelCache:    struct{}{},
+		conNukeNoCache: struct{}{},
+		conNukeCache:   struct{}{},
+	}, map[common.Hash][]byte{
 		accModNoCache: reverse(accModNoCache[:]),
 		accModCache:   reverse(accModCache[:]),
-		accDelNoCache:  nil,
-		accDelCache:    nil,
-		conNukeNoCache: nil,
-		conNukeCache:   nil,
 	}, map[common.Hash]map[common.Hash][]byte{
 		conModNoCache: {conModNoCacheSlot: reverse(conModNoCacheSlot[:])},
 		conModCache:   {conModCacheSlot: reverse(conModCacheSlot[:])},
@@ -338,13 +339,14 @@ func TestDiskPartialMerge(t *testing.T) {
 		assertStorage(conNukeCache, conNukeCacheSlot, conNukeCacheSlot[:])
 
 		// Modify or delete some accounts, flatten everything onto disk
-		if err := snaps.Update(diffRoot, baseRoot, map[common.Hash][]byte{
+		if err := snaps.Update(diffRoot, baseRoot, map[common.Hash]struct{}{
+			accDelNoCache:  struct{}{},
+			accDelCache:    struct{}{},
+			conNukeNoCache: struct{}{},
+			conNukeCache:   struct{}{},
+		}, map[common.Hash][]byte{
 			accModNoCache: reverse(accModNoCache[:]),
 			accModCache:   reverse(accModCache[:]),
-			accDelNoCache:  nil,
-			accDelCache:    nil,
-			conNukeNoCache: nil,
-			conNukeCache:   nil,
 		}, map[common.Hash]map[common.Hash][]byte{
 			conModNoCache: {conModNoCacheSlot: reverse(conModNoCacheSlot[:])},
 			conModCache:   {conModCacheSlot: reverse(conModCacheSlot[:])},

core/state/snapshot/journal.go

@@ -43,6 +43,11 @@ type journalGenerator struct {
 	Storage  uint64
 }
 
+// journalDestruct is an account deletion entry in a diffLayer's disk journal.
+type journalDestruct struct {
+	Hash common.Hash
+}
+
 // journalAccount is an account entry in a diffLayer's disk journal.
 type journalAccount struct {
 	Hash common.Hash
@@ -139,6 +144,14 @@ func loadDiffLayer(parent snapshot, r *rlp.Stream) (snapshot, error) {
 		}
 		return nil, fmt.Errorf("load diff root: %v", err)
 	}
+	var destructs []journalDestruct
+	if err := r.Decode(&destructs); err != nil {
+		return nil, fmt.Errorf("load diff destructs: %v", err)
+	}
+	destructSet := make(map[common.Hash]struct{})
+	for _, entry := range destructs {
+		destructSet[entry.Hash] = struct{}{}
+	}
 	var accounts []journalAccount
 	if err := r.Decode(&accounts); err != nil {
 		return nil, fmt.Errorf("load diff accounts: %v", err)
@@ -159,7 +172,7 @@ func loadDiffLayer(parent snapshot, r *rlp.Stream) (snapshot, error) {
 		}
 		storageData[entry.Hash] = slots
 	}
-	return loadDiffLayer(newDiffLayer(parent, root, accountData, storageData), r)
+	return loadDiffLayer(newDiffLayer(parent, root, destructSet, accountData, storageData), r)
 }
 
 // Journal writes the persistent layer generator stats into a buffer to be stored
@@ -218,6 +231,13 @@ func (dl *diffLayer) Journal(buffer *bytes.Buffer) (common.Hash, error) {
 	if err := rlp.Encode(buffer, dl.root); err != nil {
 		return common.Hash{}, err
 	}
+	destructs := make([]journalDestruct, 0, len(dl.destructSet))
+	for hash := range dl.destructSet {
+		destructs = append(destructs, journalDestruct{Hash: hash})
+	}
+	if err := rlp.Encode(buffer, destructs); err != nil {
+		return common.Hash{}, err
+	}
 	accounts := make([]journalAccount, 0, len(dl.accountData))
 	for hash, blob := range dl.accountData {
 		accounts = append(accounts, journalAccount{Hash: hash, Blob: blob})

core/state/snapshot/snapshot.go

@@ -125,7 +125,7 @@ type snapshot interface {
 	// the specified data items.
 	//
 	// Note, the maps are retained by the method to avoid copying everything.
-	Update(blockRoot common.Hash, accounts map[common.Hash][]byte, storage map[common.Hash]map[common.Hash][]byte) *diffLayer
+	Update(blockRoot common.Hash, destructs map[common.Hash]struct{}, accounts map[common.Hash][]byte, storage map[common.Hash]map[common.Hash][]byte) *diffLayer
 
 	// Journal commits an entire diff hierarchy to disk into a single journal entry.
 	// This is meant to be used during shutdown to persist the snapshot without
@@ -222,7 +222,7 @@ func (t *Tree) Snapshot(blockRoot common.Hash) Snapshot {
 
 // Update adds a new snapshot into the tree, if that can be linked to an existing
 // old parent. It is disallowed to insert a disk layer (the origin of all).
-func (t *Tree) Update(blockRoot common.Hash, parentRoot common.Hash, accounts map[common.Hash][]byte, storage map[common.Hash]map[common.Hash][]byte) error {
+func (t *Tree) Update(blockRoot common.Hash, parentRoot common.Hash, destructs map[common.Hash]struct{}, accounts map[common.Hash][]byte, storage map[common.Hash]map[common.Hash][]byte) error {
 	// Reject noop updates to avoid self-loops in the snapshot tree. This is a
 	// special case that can only happen for Clique networks where empty blocks
 	// don't modify the state (0 block subsidy).
@@ -237,7 +237,7 @@ func (t *Tree) Update(blockRoot common.Hash, parentRoot common.Hash, accounts ma
 	if parent == nil {
 		return fmt.Errorf("parent [%#x] snapshot missing", parentRoot)
 	}
-	snap := parent.Update(blockRoot, accounts, storage)
+	snap := parent.Update(blockRoot, destructs, accounts, storage)
 
 	// Save the new snapshot for later
 	t.lock.Lock()
@@ -425,26 +425,13 @@ func diffToDisk(bottom *diffLayer) *diskLayer {
 	base.stale = true
 	base.lock.Unlock()
 
-	// Push all the accounts into the database
-	for hash, data := range bottom.accountData {
+	// Destroy all the destructed accounts from the database
+	for hash := range bottom.destructSet {
 		// Skip any account not covered yet by the snapshot
 		if base.genMarker != nil && bytes.Compare(hash[:], base.genMarker) > 0 {
 			continue
 		}
-		if len(data) > 0 {
-			// Account was updated, push to disk
-			rawdb.WriteAccountSnapshot(batch, hash, data)
-			base.cache.Set(hash[:], data)
-			snapshotCleanAccountWriteMeter.Mark(int64(len(data)))
-
-			if batch.ValueSize() > ethdb.IdealBatchSize {
-				if err := batch.Write(); err != nil {
-					log.Crit("Failed to write account snapshot", "err", err)
-				}
-				batch.Reset()
-			}
-		} else {
-			// Account was deleted, remove all storage slots too
+		// Remove all storage slots
 		rawdb.DeleteAccountSnapshot(batch, hash)
 		base.cache.Set(hash[:], nil)
 
@@ -455,11 +442,27 @@ func diffToDisk(bottom *diffLayer) *diskLayer {
 				base.cache.Del(key[1:])
 
 				snapshotFlushStorageItemMeter.Mark(1)
-					snapshotFlushStorageSizeMeter.Mark(int64(len(data)))
 			}
 		}
 		it.Release()
 	}
+	// Push all updated accounts into the database
+	for hash, data := range bottom.accountData {
+		// Skip any account not covered yet by the snapshot
+		if base.genMarker != nil && bytes.Compare(hash[:], base.genMarker) > 0 {
+			continue
+		}
+		// Push the account to disk
+		rawdb.WriteAccountSnapshot(batch, hash, data)
+		base.cache.Set(hash[:], data)
+		snapshotCleanAccountWriteMeter.Mark(int64(len(data)))
+
+		if batch.ValueSize() > ethdb.IdealBatchSize {
+			if err := batch.Write(); err != nil {
+				log.Crit("Failed to write account snapshot", "err", err)
+			}
+			batch.Reset()
+		}
 		snapshotFlushAccountItemMeter.Mark(1)
 		snapshotFlushAccountSizeMeter.Mark(int64(len(data)))
 	}

core/state/snapshot/snapshot_test.go

@@ -81,7 +81,7 @@ func TestDiskLayerExternalInvalidationFullFlatten(t *testing.T) {
 	accounts := map[common.Hash][]byte{
 		common.HexToHash("0xa1"): randomAccount(),
 	}
-	if err := snaps.Update(common.HexToHash("0x02"), common.HexToHash("0x01"), accounts, nil); err != nil {
+	if err := snaps.Update(common.HexToHash("0x02"), common.HexToHash("0x01"), nil, accounts, nil); err != nil {
 		t.Fatalf("failed to create a diff layer: %v", err)
 	}
 	if n := len(snaps.layers); n != 2 {
@@ -91,7 +91,7 @@ func TestDiskLayerExternalInvalidationFullFlatten(t *testing.T) {
 	if err := snaps.Cap(common.HexToHash("0x02"), 0); err != nil {
 		t.Fatalf("failed to merge diff layer onto disk: %v", err)
 	}
-	// Since the base layer was modified, ensure that data retrievald on the external reference fail
+	// Since the base layer was modified, ensure that data retrieval on the external reference fail
 	if acc, err := ref.Account(common.HexToHash("0x01")); err != ErrSnapshotStale {
 		t.Errorf("stale reference returned account: %#x (err: %v)", acc, err)
 	}
@@ -125,10 +125,10 @@ func TestDiskLayerExternalInvalidationPartialFlatten(t *testing.T) {
 	accounts := map[common.Hash][]byte{
 		common.HexToHash("0xa1"): randomAccount(),
 	}
-	if err := snaps.Update(common.HexToHash("0x02"), common.HexToHash("0x01"), accounts, nil); err != nil {
+	if err := snaps.Update(common.HexToHash("0x02"), common.HexToHash("0x01"), nil, accounts, nil); err != nil {
 		t.Fatalf("failed to create a diff layer: %v", err)
 	}
-	if err := snaps.Update(common.HexToHash("0x03"), common.HexToHash("0x02"), accounts, nil); err != nil {
+	if err := snaps.Update(common.HexToHash("0x03"), common.HexToHash("0x02"), nil, accounts, nil); err != nil {
 		t.Fatalf("failed to create a diff layer: %v", err)
 	}
 	if n := len(snaps.layers); n != 3 {
@@ -173,10 +173,10 @@ func TestDiffLayerExternalInvalidationFullFlatten(t *testing.T) {
 	accounts := map[common.Hash][]byte{
 		common.HexToHash("0xa1"): randomAccount(),
 	}
-	if err := snaps.Update(common.HexToHash("0x02"), common.HexToHash("0x01"), accounts, nil); err != nil {
+	if err := snaps.Update(common.HexToHash("0x02"), common.HexToHash("0x01"), nil, accounts, nil); err != nil {
 		t.Fatalf("failed to create a diff layer: %v", err)
 	}
-	if err := snaps.Update(common.HexToHash("0x03"), common.HexToHash("0x02"), accounts, nil); err != nil {
+	if err := snaps.Update(common.HexToHash("0x03"), common.HexToHash("0x02"), nil, accounts, nil); err != nil {
 		t.Fatalf("failed to create a diff layer: %v", err)
 	}
 	if n := len(snaps.layers); n != 3 {
@@ -220,13 +220,13 @@ func TestDiffLayerExternalInvalidationPartialFlatten(t *testing.T) {
 	accounts := map[common.Hash][]byte{
 		common.HexToHash("0xa1"): randomAccount(),
 	}
-	if err := snaps.Update(common.HexToHash("0x02"), common.HexToHash("0x01"), accounts, nil); err != nil {
+	if err := snaps.Update(common.HexToHash("0x02"), common.HexToHash("0x01"), nil, accounts, nil); err != nil {
 		t.Fatalf("failed to create a diff layer: %v", err)
 	}
-	if err := snaps.Update(common.HexToHash("0x03"), common.HexToHash("0x02"), accounts, nil); err != nil {
+	if err := snaps.Update(common.HexToHash("0x03"), common.HexToHash("0x02"), nil, accounts, nil); err != nil {
 		t.Fatalf("failed to create a diff layer: %v", err)
 	}
-	if err := snaps.Update(common.HexToHash("0x04"), common.HexToHash("0x03"), accounts, nil); err != nil {
+	if err := snaps.Update(common.HexToHash("0x04"), common.HexToHash("0x03"), nil, accounts, nil); err != nil {
 		t.Fatalf("failed to create a diff layer: %v", err)
 	}
 	if n := len(snaps.layers); n != 4 {
@@ -280,12 +280,12 @@ func TestPostCapBasicDataAccess(t *testing.T) {
 		},
 	}
 	// The lowest difflayer
-	snaps.Update(common.HexToHash("0xa1"), common.HexToHash("0x01"), setAccount("0xa1"), nil)
-	snaps.Update(common.HexToHash("0xa2"), common.HexToHash("0xa1"), setAccount("0xa2"), nil)
-	snaps.Update(common.HexToHash("0xb2"), common.HexToHash("0xa1"), setAccount("0xb2"), nil)
+	snaps.Update(common.HexToHash("0xa1"), common.HexToHash("0x01"), nil, setAccount("0xa1"), nil)
+	snaps.Update(common.HexToHash("0xa2"), common.HexToHash("0xa1"), nil, setAccount("0xa2"), nil)
+	snaps.Update(common.HexToHash("0xb2"), common.HexToHash("0xa1"), nil, setAccount("0xb2"), nil)
 
-	snaps.Update(common.HexToHash("0xa3"), common.HexToHash("0xa2"), setAccount("0xa3"), nil)
-	snaps.Update(common.HexToHash("0xb3"), common.HexToHash("0xb2"), setAccount("0xb3"), nil)
+	snaps.Update(common.HexToHash("0xa3"), common.HexToHash("0xa2"), nil, setAccount("0xa3"), nil)
+	snaps.Update(common.HexToHash("0xb3"), common.HexToHash("0xb2"), nil, setAccount("0xb3"), nil)
 
 	// checkExist verifies if an account exiss in a snapshot
 	checkExist := func(layer *diffLayer, key string) error {

core/state/statedb.go

@@ -69,6 +69,7 @@ type StateDB struct {
 
 	snaps         *snapshot.Tree
 	snap          snapshot.Snapshot
+	snapDestructs map[common.Hash]struct{}
 	snapAccounts  map[common.Hash][]byte
 	snapStorage   map[common.Hash]map[common.Hash][]byte
 
@@ -133,6 +134,7 @@ func New(root common.Hash, db Database, snaps *snapshot.Tree) (*StateDB, error)
 	}
 	if sdb.snaps != nil {
 		if sdb.snap = sdb.snaps.Snapshot(root); sdb.snap != nil {
+			sdb.snapDestructs = make(map[common.Hash]struct{})
 			sdb.snapAccounts = make(map[common.Hash][]byte)
 			sdb.snapStorage = make(map[common.Hash]map[common.Hash][]byte)
 		}
@@ -171,8 +173,9 @@ func (s *StateDB) Reset(root common.Hash) error {
 	s.clearJournalAndRefund()
 
 	if s.snaps != nil {
-		s.snapAccounts, s.snapStorage = nil, nil
+		s.snapAccounts, s.snapDestructs, s.snapStorage = nil, nil, nil
 		if s.snap = s.snaps.Snapshot(root); s.snap != nil {
+			s.snapDestructs = make(map[common.Hash]struct{})
 			s.snapAccounts = make(map[common.Hash][]byte)
 			s.snapStorage = make(map[common.Hash]map[common.Hash][]byte)
 		}
@@ -463,15 +466,6 @@ func (s *StateDB) updateStateObject(obj *stateObject) {
 		panic(fmt.Errorf("can't encode object at %x: %v", addr[:], err))
 	}
 	s.setError(s.trie.TryUpdate(addr[:], data))
-
-	// If state snapshotting is active, cache the data til commit
-	if s.snap != nil {
-		// If the account is an empty resurrection, unmark the storage nil-ness
-		if storage, ok := s.snapStorage[obj.addrHash]; storage == nil && ok {
-			delete(s.snapStorage, obj.addrHash)
-		}
-		s.snapAccounts[obj.addrHash] = snapshot.AccountRLP(obj.data.Nonce, obj.data.Balance, obj.data.Root, obj.data.CodeHash)
-	}
 }
 
 // deleteStateObject removes the given object from the state trie.
@@ -483,12 +477,6 @@ func (s *StateDB) deleteStateObject(obj *stateObject) {
 	// Delete the account from the trie
 	addr := obj.Address()
 	s.setError(s.trie.TryDelete(addr[:]))
-
-	// If state snapshotting is active, cache the data til commit
-	if s.snap != nil {
-		s.snapAccounts[obj.addrHash] = nil // We need to maintain account deletions explicitly
-		s.snapStorage[obj.addrHash] = nil  // We need to maintain storage deletions explicitly
-	}
 }
 
 // getStateObject retrieves a state object given by the address, returning nil if
@@ -737,8 +725,23 @@ func (s *StateDB) Finalise(deleteEmptyObjects bool) {
 		}
 		if obj.suicided || (deleteEmptyObjects && obj.empty()) {
 			obj.deleted = true
+
+			// If state snapshotting is active, also mark the destruction there.
+			// Note, we can't do this only at the end of a block because multiple
+			// transactions within the same block might self destruct and then
+			// ressurrect an account and the snapshotter needs both events.
+			if s.snap != nil {
+				s.snapDestructs[obj.addrHash] = struct{}{} // We need to maintain account deletions explicitly (will remain set indefinitely)
+				delete(s.snapAccounts, obj.addrHash)       // Clear out any previously updated account data (may be recreated via a ressurrect)
+				delete(s.snapStorage, obj.addrHash)        // Clear out any previously updated storage data (may be recreated via a ressurrect)
+			}
 		} else {
 			obj.finalise()
+
+			// If state snapshotting is active, cache the data til commit
+			if s.snap != nil {
+				s.snapAccounts[obj.addrHash] = snapshot.AccountRLP(obj.data.Nonce, obj.data.Balance, obj.data.Root, obj.data.CodeHash)
+			}
 		}
 		s.stateObjectsPending[addr] = struct{}{}
 		s.stateObjectsDirty[addr] = struct{}{}
@@ -842,7 +845,7 @@ func (s *StateDB) Commit(deleteEmptyObjects bool) (common.Hash, error) {
 		}
 		// Only update if there's a state transition (skip empty Clique blocks)
 		if parent := s.snap.Root(); parent != root {
-			if err := s.snaps.Update(root, parent, s.snapAccounts, s.snapStorage); err != nil {
+			if err := s.snaps.Update(root, parent, s.snapDestructs, s.snapAccounts, s.snapStorage); err != nil {
 				log.Warn("Failed to update snapshot tree", "from", parent, "to", root, "err", err)
 			}
 			if err := s.snaps.Cap(root, 127); err != nil { // Persistent layer is 128th, the last available trie

core/vm/opcodes.go

@@ -70,7 +70,7 @@ const (
 	SHR
 	SAR
 
-	SHA3 = 0x20
+	SHA3 OpCode = 0x20
 )
 
 // 0x30 range - closure state.
@@ -101,8 +101,8 @@ const (
 	NUMBER
 	DIFFICULTY
 	GASLIMIT
-	CHAINID     = 0x46
-	SELFBALANCE = 0x47
+	CHAINID     OpCode = 0x46
+	SELFBALANCE OpCode = 0x47
 )
 
 // 0x50 range - 'storage' and execution.
@@ -213,10 +213,9 @@ const (
 	RETURN
 	DELEGATECALL
 	CREATE2
-	STATICCALL = 0xfa
-
-	REVERT       = 0xfd
-	SELFDESTRUCT = 0xff
+	STATICCALL   OpCode = 0xfa
+	REVERT       OpCode = 0xfd
+	SELFDESTRUCT OpCode = 0xff
 )
 
 // Since the opcodes aren't all in order we can't use a regular slice.