Merge pull request #177 from OffchainLabs/recreate-state

recording database updates

arbitrum/recordingdb.go

@@ -2,16 +2,19 @@ package arbitrum
 
 import (
 	"bytes"
+	"context"
 	"encoding/hex"
 	"errors"
 	"fmt"
+	"sync"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/consensus"
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/rawdb"
 	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/core/vm"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/log"
@@ -25,7 +28,7 @@ type RecordingKV struct {
 	enableBypass  bool
 }
 
-func NewRecordingKV(inner *trie.Database) *RecordingKV {
+func newRecordingKV(inner *trie.Database) *RecordingKV {
 	return &RecordingKV{inner, make(map[common.Hash][]byte), false}
 }
 
@@ -126,7 +129,7 @@ type RecordingChainContext struct {
 	initialBlockNumber     uint64
 }
 
-func NewRecordingChainContext(inner core.ChainContext, blocknumber uint64) *RecordingChainContext {
+func newRecordingChainContext(inner core.ChainContext, blocknumber uint64) *RecordingChainContext {
 	return &RecordingChainContext{
 		bc:                     inner,
 		minBlockNumberAccessed: blocknumber,
@@ -149,9 +152,83 @@ func (r *RecordingChainContext) GetMinBlockNumberAccessed() uint64 {
 	return r.minBlockNumberAccessed
 }
 
-func PrepareRecording(blockchain *core.BlockChain, lastBlockHeader *types.Header) (*state.StateDB, core.ChainContext, *RecordingKV, error) {
-	rawTrie := blockchain.StateCache().TrieDB()
-	recordingKeyValue := NewRecordingKV(rawTrie)
+type RecordingDatabase struct {
+	db         state.Database
+	bc         *core.BlockChain
+	mutex      sync.Mutex // protects StateFor and Dereference
+	references int64
+}
+
+func NewRecordingDatabase(ethdb ethdb.Database, blockchain *core.BlockChain) *RecordingDatabase {
+	return &RecordingDatabase{
+		db: state.NewDatabaseWithConfig(ethdb, &trie.Config{Cache: 16}), //TODO cache needed? configurable?
+		bc: blockchain,
+	}
+}
+
+// Normal geth state.New + Reference is not atomic vs Dereference. This one is.
+// This function does not recreate a state
+func (r *RecordingDatabase) StateFor(header *types.Header) (*state.StateDB, error) {
+	r.mutex.Lock()
+	defer r.mutex.Unlock()
+
+	sdb, err := state.NewDeterministic(header.Root, r.db)
+	if err == nil {
+		r.referenceRootLockHeld(header.Root)
+	}
+	return sdb, err
+}
+
+func (r *RecordingDatabase) Dereference(header *types.Header) {
+	if header != nil {
+		r.dereferenceRoot(header.Root)
+	}
+}
+
+func (r *RecordingDatabase) WriteStateToDatabase(header *types.Header) error {
+	if header != nil {
+		return r.db.TrieDB().Commit(header.Root, true, nil)
+	}
+	return nil
+}
+
+// lock must be held when calling that
+func (r *RecordingDatabase) referenceRootLockHeld(root common.Hash) {
+	r.references++
+	r.db.TrieDB().Reference(root, common.Hash{})
+}
+
+func (r *RecordingDatabase) dereferenceRoot(root common.Hash) {
+	r.mutex.Lock()
+	defer r.mutex.Unlock()
+	r.references--
+	r.db.TrieDB().Dereference(root)
+}
+
+func (r *RecordingDatabase) addStateVerify(statedb *state.StateDB, expected common.Hash) error {
+	r.mutex.Lock()
+	defer r.mutex.Unlock()
+	result, err := statedb.Commit(true)
+	if err != nil {
+		return err
+	}
+	if result != expected {
+		return fmt.Errorf("bad root hash expected: %v got: %v", expected, result)
+	}
+	r.referenceRootLockHeld(result)
+	return nil
+}
+
+type StateBuildingLogFunction func(targetHeader, header *types.Header, hasState bool)
+
+func (r *RecordingDatabase) PrepareRecording(ctx context.Context, lastBlockHeader *types.Header, logFunc StateBuildingLogFunction) (*state.StateDB, core.ChainContext, *RecordingKV, error) {
+	_, err := r.GetOrRecreateState(ctx, lastBlockHeader, logFunc)
+	if err != nil {
+		return nil, nil, nil, err
+	}
+	finalDereference := lastBlockHeader // dereference in case of error
+	defer func() { r.Dereference(finalDereference) }()
+	recordingKeyValue := newRecordingKV(r.db.TrieDB())
 
 	recordingStateDatabase := state.NewDatabase(rawdb.NewDatabase(recordingKeyValue))
 	var prevRoot common.Hash
@@ -167,29 +244,99 @@ func PrepareRecording(blockchain *core.BlockChain, lastBlockHeader *types.Header
 		if !lastBlockHeader.Number.IsUint64() {
 			return nil, nil, nil, errors.New("block number not uint64")
 		}
-		recordingChainContext = NewRecordingChainContext(blockchain, lastBlockHeader.Number.Uint64())
+		recordingChainContext = newRecordingChainContext(r.bc, lastBlockHeader.Number.Uint64())
 	}
+	finalDereference = nil
 	return recordingStateDb, recordingChainContext, recordingKeyValue, nil
 }
 
-func PreimagesFromRecording(chainContextIf core.ChainContext, recordingDb *RecordingKV) (map[common.Hash][]byte, error) {
+func (r *RecordingDatabase) PreimagesFromRecording(chainContextIf core.ChainContext, recordingDb *RecordingKV) (map[common.Hash][]byte, error) {
 	entries := recordingDb.GetRecordedEntries()
 	recordingChainContext, ok := chainContextIf.(*RecordingChainContext)
 	if (recordingChainContext == nil) || (!ok) {
 		return nil, errors.New("recordingChainContext invalid")
 	}
-	blockchain, ok := recordingChainContext.bc.(*core.BlockChain)
-	if (blockchain == nil) || (!ok) {
-		return nil, errors.New("blockchain invalid")
-	}
+
 	for i := recordingChainContext.GetMinBlockNumberAccessed(); i <= recordingChainContext.initialBlockNumber; i++ {
-		header := blockchain.GetHeaderByNumber(i)
+		header := r.bc.GetHeaderByNumber(i)
 		hash := header.Hash()
 		bytes, err := rlp.EncodeToBytes(header)
 		if err != nil {
-			panic(fmt.Sprintf("Error RLP encoding header: %v\n", err))
+			return nil, fmt.Errorf("Error RLP encoding header: %v\n", err)
 		}
 		entries[hash] = bytes
 	}
 	return entries, nil
 }
+
+func (r *RecordingDatabase) GetOrRecreateState(ctx context.Context, header *types.Header, logFunc StateBuildingLogFunction) (*state.StateDB, error) {
+	stateDb, err := r.StateFor(header)
+	if err == nil {
+		return stateDb, nil
+	}
+	returnedBlockNumber := header.Number.Uint64()
+	genesis := r.bc.Config().ArbitrumChainParams.GenesisBlockNum
+	currentHeader := header
+	var lastRoot common.Hash
+	for ctx.Err() == nil {
+		if logFunc != nil {
+			logFunc(header, currentHeader, false)
+		}
+		if currentHeader.Number.Uint64() <= genesis {
+			return nil, fmt.Errorf("moved beyond genesis looking for state looking for %d, genesis %d, err %w", returnedBlockNumber, genesis, err)
+		}
+		currentHeader = r.bc.GetHeader(currentHeader.ParentHash, currentHeader.Number.Uint64()-1)
+		if currentHeader == nil {
+			return nil, fmt.Errorf("chain doesn't contain parent of block %d hash %v", currentHeader.Number, currentHeader.Hash())
+		}
+		stateDb, err = r.StateFor(currentHeader)
+		if err == nil {
+			lastRoot = currentHeader.Root
+			break
+		}
+	}
+	defer func() {
+		if (lastRoot != common.Hash{}) {
+			r.dereferenceRoot(lastRoot)
+		}
+	}()
+	blockToRecreate := currentHeader.Number.Uint64() + 1
+	prevHash := currentHeader.Hash()
+	for ctx.Err() == nil {
+		block := r.bc.GetBlockByNumber(blockToRecreate)
+		if block == nil {
+			return nil, fmt.Errorf("block not found while recreating: %d", blockToRecreate)
+		}
+		if block.ParentHash() != prevHash {
+			return nil, fmt.Errorf("reorg detected: number %d expectedPrev: %v foundPrev: %v", blockToRecreate, prevHash, block.ParentHash())
+		}
+		prevHash = block.Hash()
+		if logFunc != nil {
+			logFunc(header, block.Header(), true)
+		}
+		_, _, _, err := r.bc.Processor().Process(block, stateDb, vm.Config{})
+		if err != nil {
+			return nil, fmt.Errorf("failed recreating state for block %d : %w", blockToRecreate, err)
+		}
+		err = r.addStateVerify(stateDb, block.Root())
+		if err != nil {
+			return nil, fmt.Errorf("failed commiting state for block %d : %w", blockToRecreate, err)
+		}
+		r.dereferenceRoot(lastRoot)
+		lastRoot = block.Root()
+		if blockToRecreate >= returnedBlockNumber {
+			if block.Hash() != header.Hash() {
+				return nil, fmt.Errorf("blockHash doesn't match when recreating number: %d expected: %v got: %v", blockToRecreate, header.Hash(), block.Hash())
+			}
+			// don't dereference this one
+			lastRoot = common.Hash{}
+			return stateDb, nil
+		}
+		blockToRecreate++
+	}
+	return nil, ctx.Err()
+}
+
+func (r *RecordingDatabase) ReferenceCount() int64 {
+	return r.references
+}

core/state/database.go

@@ -19,6 +19,7 @@ package state
 import (
 	"errors"
 	"fmt"
+	"runtime"
 
 	"github.com/VictoriaMetrics/fastcache"
 	"github.com/ethereum/go-ethereum/common"
@@ -118,11 +119,13 @@ func NewDatabase(db ethdb.Database) Database {
 // large memory cache.
 func NewDatabaseWithConfig(db ethdb.Database, config *trie.Config) Database {
 	csc, _ := lru.New(codeSizeCacheSize)
-	return &cachingDB{
+	cdb := &cachingDB{
 		db:            trie.NewDatabaseWithConfig(db, config),
 		codeSizeCache: csc,
 		codeCache:     fastcache.New(codeCacheSize),
 	}
+	runtime.SetFinalizer(cdb, (*cachingDB).finalizer)
+	return cdb
 }
 
 type cachingDB struct {
@@ -140,6 +143,11 @@ func (db *cachingDB) OpenTrie(root common.Hash) (Trie, error) {
 	return tr, nil
 }
 
+// fastcache chunks are not mannaged by GC.
+func (db *cachingDB) finalizer() {
+	db.codeCache.Reset()
+}
+
 // OpenStorageTrie opens the storage trie of an account.
 func (db *cachingDB) OpenStorageTrie(addrHash, root common.Hash) (Trie, error) {
 	tr, err := trie.NewSecure(addrHash, root, db.db)

trie/database.go

@@ -297,6 +297,7 @@ func NewDatabaseWithConfig(diskdb ethdb.KeyValueStore, config *Config) *Database
 	if config == nil || config.Preimages { // TODO(karalabe): Flip to default off in the future
 		db.preimages = make(map[common.Hash][]byte)
 	}
+	runtime.SetFinalizer(db, (*Database).finalizer)
 	return db
 }
 
@@ -305,6 +306,13 @@ func (db *Database) DiskDB() ethdb.KeyValueStore {
 	return db.diskdb
 }
 
+// must call Reset() to reclaim memory used by fastcache
+func (db *Database) finalizer() {
+	if db.cleans != nil {
+		db.cleans.Reset()
+	}
+}
+
 // insert inserts a collapsed trie node into the memory database.
 // The blob size must be specified to allow proper size tracking.
 // All nodes inserted by this function will be reference tracked