consensus, core, eth, internal: further removal of td

consensus/beacon/consensus.go

@@ -61,7 +61,8 @@ var (
 // is only used for necessary consensus checks. The legacy consensus engine can be any
 // engine implements the consensus interface (except the beacon itself).
 type Beacon struct {
-	ethone consensus.Engine // Original consensus engine used in eth1, e.g. ethash or clique
+	ethone   consensus.Engine // Original consensus engine used in eth1, e.g. ethash or clique
+	ttdblock *uint64          // Merge block-number for testchain generation without TTDs
 }
 
 // New creates a consensus engine with the given embedded eth1 engine.
@@ -72,6 +73,16 @@ func New(ethone consensus.Engine) *Beacon {
 	return &Beacon{ethone: ethone}
 }
 
+// TestingTTDBlock is a replacement mechanism for TTD-based pre-/post-merge
+// splitting. With chain history deletion, TD calculations become impossible.
+// This is fine for progressing the live chain, but to be able to generate test
+// chains, we do need a split point. This method supports setting an explicit
+// block number to use as the splitter *for testing*, instead of having to keep
+// the notion of TDs in the client just for testing.
+func (beacon *Beacon) TestingTTDBlock(number uint64) {
+	beacon.ttdblock = &number
+}
+
 // Author implements consensus.Engine, returning the verified author of the block.
 func (beacon *Beacon) Author(header *types.Header) (common.Address, error) {
 	if !beacon.IsPoSHeader(header) {
@@ -83,8 +94,8 @@ func (beacon *Beacon) Author(header *types.Header) (common.Address, error) {
 // VerifyHeader checks whether a header conforms to the consensus rules of the
 // stock Ethereum consensus engine.
 func (beacon *Beacon) VerifyHeader(chain consensus.ChainHeaderReader, header *types.Header) error {
-	// During the live merge transision, the consensus engine used the terminal
-	// total difficulty to detect when PoW (PoA) switched to PoS. Maintainig the
+	// During the live merge transition, the consensus engine used the terminal
+	// total difficulty to detect when PoW (PoA) switched to PoS. Maintaining the
 	// total difficulty values however require applying all the blocks from the
 	// genesis to build up the TD. This stops being a possibility if the tail of
 	// the chain is pruned already during sync.
@@ -92,7 +103,7 @@ func (beacon *Beacon) VerifyHeader(chain consensus.ChainHeaderReader, header *ty
 	// One heuristic that can be used to distinguis pre-merge and post-merge
 	// blocks is whether their *difficulty* is >0 or ==0 respectively. This of
 	// course would mean that we cannot prove anymore for a past chain that it
-	// truly transisioned at the correct TTD, but if we consider that ancient
+	// truly transitioned at the correct TTD, but if we consider that ancient
 	// point in time finalized a long time ago, there should be no attempt from
 	// the consensus client to rewrite very old history.
 	//
@@ -130,34 +141,16 @@ func errOut(n int, err error) chan error {
 // will be treated legacy PoW headers.
 // Note, this function will not verify the header validity but just split them.
 func (beacon *Beacon) splitHeaders(chain consensus.ChainHeaderReader, headers []*types.Header) ([]*types.Header, []*types.Header, error) {
-	// TTD is not defined yet, all headers should be in legacy format.
-	ttd := chain.Config().TerminalTotalDifficulty
-	ptd := chain.GetTd(headers[0].ParentHash, headers[0].Number.Uint64()-1)
-	if ptd == nil {
-		return nil, nil, consensus.ErrUnknownAncestor
-	}
-	// The entire header batch already crosses the transition.
-	if ptd.Cmp(ttd) >= 0 {
-		return nil, headers, nil
-	}
 	var (
 		preHeaders  = headers
 		postHeaders []*types.Header
-		td          = new(big.Int).Set(ptd)
-		tdPassed    bool
 	)
 	for i, header := range headers {
-		if tdPassed {
+		if header.Difficulty.Sign() == 0 {
 			preHeaders = headers[:i]
 			postHeaders = headers[i:]
 			break
 		}
-		td = td.Add(td, header.Difficulty)
-		if td.Cmp(ttd) >= 0 {
-			// This is the last PoW header, it still belongs to
-			// the preHeaders, so we cannot split+break yet.
-			tdPassed = true
-		}
 	}
 	return preHeaders, postHeaders, nil
 }
@@ -350,12 +343,15 @@ func (beacon *Beacon) verifyHeaders(chain consensus.ChainHeaderReader, headers [
 // Prepare implements consensus.Engine, initializing the difficulty field of a
 // header to conform to the beacon protocol. The changes are done inline.
 func (beacon *Beacon) Prepare(chain consensus.ChainHeaderReader, header *types.Header) error {
-	// Transition isn't triggered yet, use the legacy rules for preparation.
-	reached, err := IsTTDReached(chain, header.ParentHash, header.Number.Uint64()-1)
-	if err != nil {
-		return err
-	}
-	if !reached {
+	// The beacon engine requires access to total difficulties to be able to
+	// seal pre-merge and post-merge blocks. With the transition to removing
+	// old blocks, TDs become unaccessible, thus making TTD based pre-/post-
+	// merge decisions impossible.
+	//
+	// We do not need to seal non-merge blocks anymore live, but we do need
+	// to be able to generate test chains, thus we're reverting to a testing-
+	// settable field to direct that.
+	if beacon.ttdblock != nil && *beacon.ttdblock >= header.Number.Uint64() {
 		return beacon.ethone.Prepare(chain, header)
 	}
 	header.Difficulty = beaconDifficulty
@@ -465,8 +461,15 @@ func (beacon *Beacon) SealHash(header *types.Header) common.Hash {
 // the difficulty that a new block should have when created at time
 // given the parent block's time and difficulty.
 func (beacon *Beacon) CalcDifficulty(chain consensus.ChainHeaderReader, time uint64, parent *types.Header) *big.Int {
-	// Transition isn't triggered yet, use the legacy rules for calculation
-	if reached, _ := IsTTDReached(chain, parent.Hash(), parent.Number.Uint64()); !reached {
+	// The beacon engine requires access to total difficulties to be able to
+	// seal pre-merge and post-merge blocks. With the transition to removing
+	// old blocks, TDs become unaccessible, thus making TTD based pre-/post-
+	// merge decisions impossible.
+	//
+	// We do not need to seal non-merge blocks anymore live, but we do need
+	// to be able to generate test chains, thus we're reverting to a testing-
+	// settable field to direct that.
+	if beacon.ttdblock != nil && *beacon.ttdblock > parent.Number.Uint64() {
 		return beacon.ethone.CalcDifficulty(chain, time, parent)
 	}
 	return beaconDifficulty
@@ -507,14 +510,3 @@ func (beacon *Beacon) SetThreads(threads int) {
 		th.SetThreads(threads)
 	}
 }
-
-// IsTTDReached checks if the TotalTerminalDifficulty has been surpassed on the `parentHash` block.
-// It depends on the parentHash already being stored in the database.
-// If the parentHash is not stored in the database a UnknownAncestor error is returned.
-func IsTTDReached(chain consensus.ChainHeaderReader, parentHash common.Hash, parentNumber uint64) (bool, error) {
-	td := chain.GetTd(parentHash, parentNumber)
-	if td == nil {
-		return false, consensus.ErrUnknownAncestor
-	}
-	return td.Cmp(chain.Config().TerminalTotalDifficulty) >= 0, nil
-}

consensus/consensus.go

@@ -45,9 +45,6 @@ type ChainHeaderReader interface {
 
 	// GetHeaderByHash retrieves a block header from the database by its hash.
 	GetHeaderByHash(hash common.Hash) *types.Header
-
-	// GetTd retrieves the total difficulty from the database by hash and number.
-	GetTd(hash common.Hash, number uint64) *big.Int
 }
 
 // ChainReader defines a small collection of methods needed to access the local

core/chain_makers.go

@@ -726,7 +726,3 @@ func (cm *chainMaker) GetHeader(hash common.Hash, number uint64) *types.Header {
 func (cm *chainMaker) GetBlock(hash common.Hash, number uint64) *types.Block {
 	return cm.blockByNumber(number)
 }
-
-func (cm *chainMaker) GetTd(hash common.Hash, number uint64) *big.Int {
-	return nil // not supported
-}

eth/catalyst/api_test.go

@@ -66,6 +66,8 @@ func generateMergeChain(n int, merged bool) (*core.Genesis, []*types.Block) {
 	if merged {
 		config.TerminalTotalDifficulty = common.Big0
 		engine = beaconConsensus.NewFaker()
+	} else {
+		engine.(*beaconConsensus.Beacon).TestingTTDBlock(uint64(n))
 	}
 	genesis := &core.Genesis{
 		Config: &config,
@@ -101,7 +103,6 @@ func generateMergeChain(n int, merged bool) (*core.Genesis, []*types.Block) {
 		}
 		config.TerminalTotalDifficulty = totalDifficulty
 	}
-
 	return genesis, blocks
 }
 

eth/gasprice/gasprice_test.go

@@ -25,7 +25,6 @@ import (
 	"testing"
 
 	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/consensus"
 	"github.com/ethereum/go-ethereum/consensus/beacon"
 	"github.com/ethereum/go-ethereum/consensus/ethash"
 	"github.com/ethereum/go-ethereum/core"
@@ -148,7 +147,10 @@ func newTestBackend(t *testing.T, londonBlock *big.Int, cancunBlock *big.Int, pe
 	config.LondonBlock = londonBlock
 	config.ArrowGlacierBlock = londonBlock
 	config.GrayGlacierBlock = londonBlock
-	var engine consensus.Engine = beacon.New(ethash.NewFaker())
+
+	engine := beacon.New(ethash.NewFaker())
+	engine.TestingTTDBlock(testHead + 1)
+
 	td := params.GenesisDifficulty.Uint64()
 
 	if cancunBlock != nil {

eth/protocols/eth/peer.go

@@ -18,7 +18,6 @@ package eth
 
 import (
 	"math/rand"
-	"sync"
 
 	mapset "github.com/deckarep/golang-set/v2"
 	"github.com/ethereum/go-ethereum/common"
@@ -59,7 +58,6 @@ type Peer struct {
 	resDispatch chan *response // Dispatch channel to fulfil pending requests and untrack them
 
 	term chan struct{} // Termination channel to stop the broadcasters
-	lock sync.RWMutex  // Mutex protecting the internal fields
 }
 
 // NewPeer creates a wrapper for a network connection and negotiated  protocol

eth/tracers/internal/tracetest/supply_test.go

@@ -544,9 +544,8 @@ func TestSupplySelfdestructItselfAndRevert(t *testing.T) {
 }
 
 func testSupplyTracer(t *testing.T, genesis *core.Genesis, gen func(*core.BlockGen)) ([]supplyInfo, *core.BlockChain, error) {
-	var (
-		engine = beacon.New(ethash.NewFaker())
-	)
+	engine := beacon.New(ethash.NewFaker())
+	engine.TestingTTDBlock(1)
 
 	traceOutputPath := filepath.ToSlash(t.TempDir())
 	traceOutputFilename := path.Join(traceOutputPath, "supply.jsonl")

internal/ethapi/api_test.go

@@ -565,12 +565,6 @@ func (b testBackend) GetReceipts(ctx context.Context, hash common.Hash) (types.R
 	receipts := rawdb.ReadReceipts(b.db, hash, header.Number.Uint64(), header.Time, b.chain.Config())
 	return receipts, nil
 }
-func (b testBackend) GetTd(ctx context.Context, hash common.Hash) *big.Int {
-	if b.pending != nil && hash == b.pending.Hash() {
-		return nil
-	}
-	return big.NewInt(1)
-}
 func (b testBackend) GetEVM(ctx context.Context, state *state.StateDB, header *types.Header, vmConfig *vm.Config, blockContext *vm.BlockContext) *vm.EVM {
 	if vmConfig == nil {
 		vmConfig = b.chain.GetVMConfig()

internal/ethapi/transaction_args_test.go

@@ -369,7 +369,6 @@ func (b *backendMock) GetReceipts(ctx context.Context, hash common.Hash) (types.
 func (b *backendMock) GetLogs(ctx context.Context, blockHash common.Hash, number uint64) ([][]*types.Log, error) {
 	return nil, nil
 }
-func (b *backendMock) GetTd(ctx context.Context, hash common.Hash) *big.Int { return nil }
 func (b *backendMock) GetEVM(ctx context.Context, state *state.StateDB, header *types.Header, vmConfig *vm.Config, blockCtx *vm.BlockContext) *vm.EVM {
 	return nil
 }