feat(feynman): L2 fee calculation (#1199)

* Update L2 base fee calculation to account for Feynman

* Update consensus/misc/eip1559.go

Co-authored-by: Péter Garamvölgyi <peter@scroll.io>

* Use dedicated system parameter provingBaseFee

* Merge and change initialBaseFee

* Check on parent not to fail tests

* fix test

* fix golint

* fix goimport

* fix unit tests

* check config.IsFeynman(parent.Time)

* Update consensus/misc/eip1559.go

* fix fee transition

* remove an incorrect comment

* reuse baseFeeOverhead as proving base fee

* update da-codec commit

* address comments

* add a comment

* add base fee max check

* add upstream 1559 tests

* bump version

---------

Co-authored-by: Péter Garamvölgyi <peter@scroll.io>
Co-authored-by: colin <102356659+colinlyguo@users.noreply.github.com>
Co-authored-by: colinlyguo <colinlyguo@scroll.io>

consensus/misc/eip1559.go

@@ -102,13 +102,87 @@ func VerifyEip1559Header(config *params.ChainConfig, parent, header *types.Heade
 }
 
 // CalcBaseFee calculates the basefee of the header.
-func CalcBaseFee(config *params.ChainConfig, parent *types.Header, parentL1BaseFee *big.Int) *big.Int {
+func CalcBaseFee(config *params.ChainConfig, parent *types.Header, parentL1BaseFee *big.Int, currentHeaderTime uint64) *big.Int {
 	if config.Clique != nil && config.Clique.ShadowForkHeight != 0 && parent.Number.Uint64() >= config.Clique.ShadowForkHeight {
 		return big.NewInt(10000000) // 0.01 Gwei
 	}
 
 	scalar, overhead := ReadL2BaseFeeCoefficients()
-	return calcBaseFee(scalar, overhead, parentL1BaseFee)
+
+	if parent == nil || parent.Number == nil || !config.IsFeynman(currentHeaderTime) {
+		return calcBaseFee(scalar, overhead, parentL1BaseFee)
+	}
+	// In Feynman base fee calculation, we reuse the contract's baseFeeOverhead slot as the proving base fee.
+	return calcBaseFeeFeynman(config, parent, overhead)
+}
+
+// calcBaseFeeFeynman calculates the basefee of the header for Feynman fork.
+func calcBaseFeeFeynman(config *params.ChainConfig, parent *types.Header, overhead *big.Int) *big.Int {
+	baseFeeEIP1559 := calcBaseFeeEIP1559(config, parent)
+	baseFee := new(big.Int).Set(baseFeeEIP1559)
+	baseFee.Add(baseFee, overhead)
+
+	return baseFee
+}
+
+// CalcBaseFee calculates the basefee of the header.
+func calcBaseFeeEIP1559(config *params.ChainConfig, parent *types.Header) *big.Int {
+	// If the current block is the first EIP-1559 block, return the InitialBaseFee.
+	if !config.IsFeynman(parent.Time) {
+		// If the parent block is not nil, return its base fee to make fee transition smooth.
+		if parent.BaseFee != nil {
+			return new(big.Int).Set(parent.BaseFee)
+		}
+		return new(big.Int).SetUint64(params.InitialBaseFee)
+	}
+
+	parentBaseFeeEIP1559 := extractBaseFeeEIP1559(config, parent.BaseFee)
+	parentGasTarget := parent.GasLimit / config.ElasticityMultiplier()
+	// If the parent gasUsed is the same as the target, the baseFee remains unchanged.
+	if parent.GasUsed == parentGasTarget {
+		return new(big.Int).Set(parentBaseFeeEIP1559)
+	}
+
+	var (
+		num   = new(big.Int)
+		denom = new(big.Int)
+	)
+
+	if parent.GasUsed > parentGasTarget {
+		// If the parent block used more gas than its target, the baseFee should increase.
+		// max(1, parentBaseFee * gasUsedDelta / parentGasTarget / baseFeeChangeDenominator)
+		num.SetUint64(parent.GasUsed - parentGasTarget)
+		num.Mul(num, parentBaseFeeEIP1559)
+		num.Div(num, denom.SetUint64(parentGasTarget))
+		num.Div(num, denom.SetUint64(config.BaseFeeChangeDenominator()))
+		if num.Cmp(common.Big1) < 0 {
+			return num.Add(parentBaseFeeEIP1559, common.Big1)
+		}
+		baseFee := num.Add(parentBaseFeeEIP1559, num)
+		if baseFee.Cmp(big.NewInt(MaximumL2BaseFee)) > 0 {
+			baseFee = big.NewInt(MaximumL2BaseFee)
+		}
+		return baseFee
+	} else {
+		// Otherwise if the parent block used less gas than its target, the baseFee should decrease.
+		// max(0, parentBaseFee * gasUsedDelta / parentGasTarget / baseFeeChangeDenominator)
+		num.SetUint64(parentGasTarget - parent.GasUsed)
+		num.Mul(num, parentBaseFeeEIP1559)
+		num.Div(num, denom.SetUint64(parentGasTarget))
+		num.Div(num, denom.SetUint64(config.BaseFeeChangeDenominator()))
+
+		baseFee := num.Sub(parentBaseFeeEIP1559, num)
+		if baseFee.Cmp(common.Big0) < 0 {
+			baseFee = common.Big0
+		}
+		return baseFee
+	}
+}
+
+func extractBaseFeeEIP1559(config *params.ChainConfig, baseFee *big.Int) *big.Int {
+	_, overhead := ReadL2BaseFeeCoefficients()
+	// In Feynman base fee calculation, we reuse the contract's baseFeeOverhead slot as the proving base fee.
+	return new(big.Int).Sub(baseFee, overhead)
 }
 
 // MinBaseFee calculates the minimum L2 base fee based on the current coefficients.

consensus/misc/eip1559_test.go

@@ -20,6 +20,7 @@ import (
 	"math/big"
 	"testing"
 
+	"github.com/scroll-tech/go-ethereum/common"
 	"github.com/scroll-tech/go-ethereum/core/types"
 	"github.com/scroll-tech/go-ethereum/params"
 )
@@ -124,7 +125,33 @@ func TestCalcBaseFee(t *testing.T) {
 		config := config()
 		UpdateL2BaseFeeScalar(big.NewInt(10000000))
 		UpdateL2BaseFeeOverhead(big.NewInt(1))
-		if have, want := CalcBaseFee(config, nil, big.NewInt(test.parentL1BaseFee)), big.NewInt(test.expectedL2BaseFee); have.Cmp(want) != 0 {
+		if have, want := CalcBaseFee(config, nil, big.NewInt(test.parentL1BaseFee), 0), big.NewInt(test.expectedL2BaseFee); have.Cmp(want) != 0 {
+			t.Errorf("test %d: have %d  want %d, ", i, have, want)
+		}
+	}
+
+	tests1559 := []struct {
+		parentBaseFee   int64
+		parentGasLimit  uint64
+		parentGasUsed   uint64
+		expectedBaseFee int64
+	}{
+		{1000000000, 20000000, 10000000, 1000000000}, // usage == target
+		{1000000001, 20000000, 9000000, 987500001},   // usage below target
+		{1000000001, 20000000, 11000000, 1012500001}, // usage above target
+	}
+	for i, test := range tests1559 {
+		parent := &types.Header{
+			Number:   common.Big32,
+			GasLimit: test.parentGasLimit,
+			GasUsed:  test.parentGasUsed,
+			BaseFee:  big.NewInt(test.parentBaseFee),
+		}
+		config := config()
+		UpdateL2BaseFeeOverhead(big.NewInt(1))
+		var feynmanTime uint64
+		config.FeynmanTime = &feynmanTime
+		if have, want := CalcBaseFee(config, parent, big.NewInt(1), 1), big.NewInt(test.expectedBaseFee); have.Cmp(want) != 0 {
 			t.Errorf("test %d: have %d  want %d, ", i, have, want)
 		}
 	}
@@ -144,7 +171,7 @@ func TestCalcBaseFee(t *testing.T) {
 	for i, test := range testsWithDefaults {
 		UpdateL2BaseFeeScalar(big.NewInt(34000000000000))
 		UpdateL2BaseFeeOverhead(big.NewInt(15680000))
-		if have, want := CalcBaseFee(config(), nil, big.NewInt(test.parentL1BaseFee)), big.NewInt(test.expectedL2BaseFee); have.Cmp(want) != 0 {
+		if have, want := CalcBaseFee(config(), nil, big.NewInt(test.parentL1BaseFee), 0), big.NewInt(test.expectedL2BaseFee); have.Cmp(want) != 0 {
 			t.Errorf("test %d: have %d  want %d, ", i, have, want)
 		}
 	}

core/chain_makers.go

@@ -308,7 +308,7 @@ func makeHeader(chain consensus.ChainReader, parent *types.Block, state *state.S
 	}
 	if chain.Config().IsCurie(header.Number) {
 		parentL1BaseFee := fees.GetL1BaseFee(state)
-		header.BaseFee = misc.CalcBaseFee(chain.Config(), parent.Header(), parentL1BaseFee)
+		header.BaseFee = misc.CalcBaseFee(chain.Config(), parent.Header(), parentL1BaseFee, header.Time)
 	}
 	return header
 }

core/genesis.go

@@ -317,7 +317,7 @@ func (g *Genesis) ToBlock(db ethdb.Database) *types.Block {
 		if g.BaseFee != nil {
 			head.BaseFee = g.BaseFee
 		} else {
-			head.BaseFee = misc.CalcBaseFee(g.Config, nil, big.NewInt(0))
+			head.BaseFee = misc.CalcBaseFee(g.Config, nil, big.NewInt(0), head.Time)
 		}
 	}
 	statedb.Commit(false)

core/state_processor_test.go

@@ -241,7 +241,7 @@ func TestStateProcessorErrors(t *testing.T) {
 				txs: []*types.Transaction{
 					mkSetCodeTx(0, common.Address{}, params.TxGas, big.NewInt(params.InitialBaseFee), big.NewInt(params.InitialBaseFee), nil),
 				},
-				want: "could not apply tx 0 [0xc18d10f4c809dbdfa1a074c3300de9bc4b7f16a20f0ec667f6f67312b71b956a]: EIP-7702 transaction with empty auth list (sender 0x71562b71999873DB5b286dF957af199Ec94617F7)",
+				want: "could not apply tx 0 [0xa230ea82ab24a8e60aca9edfe901bab53c92d0d8850f13c3f72513608229e2f3]: EIP-7702 transaction with empty auth list (sender 0x71562b71999873DB5b286dF957af199Ec94617F7)",
 			},
 			// ErrSetCodeTxCreate cannot be tested here: it is impossible to create a SetCode-tx with nil `to`.
 			// The EstimateGas API tests test this case.
@@ -391,13 +391,13 @@ func TestStateProcessorErrors(t *testing.T) {
 		}{
 			{ // ErrMaxInitCodeSizeExceeded
 				txs: []*types.Transaction{
-					mkDynamicCreationTx(0, 520000, common.Big0, misc.CalcBaseFee(config, genesis.Header(), parentL1BaseFee), tooBigInitCode[:]),
+					mkDynamicCreationTx(0, 520000, common.Big0, misc.CalcBaseFee(config, genesis.Header(), parentL1BaseFee, 0), tooBigInitCode[:]),
 				},
 				want: "could not apply tx 0 [0xe0d03426cecc04467410064cb4de02012fc069d2462282735d7dfcb9dea9f63b]: max initcode size exceeded: code size 49153 limit 49152",
 			},
 			{ // ErrIntrinsicGas: Not enough gas to cover init code
 				txs: []*types.Transaction{
-					mkDynamicCreationTx(0, 54299, common.Big0, misc.CalcBaseFee(config, genesis.Header(), parentL1BaseFee), smallInitCode[:]),
+					mkDynamicCreationTx(0, 54299, common.Big0, misc.CalcBaseFee(config, genesis.Header(), parentL1BaseFee, 0), smallInitCode[:]),
 				},
 				want: "could not apply tx 0 [0x98e54c5ecfa7986a66480d65ba32f2c6a2a6aedc3a67abb91b1e118b0717ed2d]: intrinsic gas too low: have 54299, want 54300",
 			},
@@ -436,7 +436,7 @@ func GenerateBadBlock(parent *types.Block, engine consensus.Engine, txs types.Tr
 
 	if config.IsCurie(header.Number) {
 		parentL1BaseFee := big.NewInt(1000000000) // 1 gwei
-		header.BaseFee = misc.CalcBaseFee(config, parent.Header(), parentL1BaseFee)
+		header.BaseFee = misc.CalcBaseFee(config, parent.Header(), parentL1BaseFee, header.Time)
 	}
 	var receipts []*types.Receipt
 	// The post-state result doesn't need to be correct (this is a bad block), but we do need something there

core/tx_pool.go

@@ -1459,7 +1459,8 @@ func (pool *TxPool) runReorg(done chan struct{}, reset *txpoolResetRequest, dirt
 		pool.demoteUnexecutables()
 		if reset.newHead != nil && pool.chainconfig.IsCurie(new(big.Int).Add(reset.newHead.Number, big.NewInt(1))) {
 			l1BaseFee := fees.GetL1BaseFee(pool.currentState)
-			pendingBaseFee := misc.CalcBaseFee(pool.chainconfig, reset.newHead, l1BaseFee)
+			// Use time.Now() as the current block time to calculate the pending base fee.
+			pendingBaseFee := misc.CalcBaseFee(pool.chainconfig, reset.newHead, l1BaseFee, uint64(time.Now().Unix()))
 			pool.priced.SetBaseFee(pendingBaseFee)
 		}
 		// Update all accounts to the latest known pending nonce

eth/catalyst/api.go

@@ -148,7 +148,7 @@ func (api *consensusAPI) AssembleBlock(params assembleBlockParams) (*executableD
 			return nil, err
 		}
 		parentL1BaseFee := fees.GetL1BaseFee(stateDb)
-		header.BaseFee = misc.CalcBaseFee(config, parent.Header(), parentL1BaseFee)
+		header.BaseFee = misc.CalcBaseFee(config, parent.Header(), parentL1BaseFee, header.Time)
 	}
 	err = api.eth.Engine().Prepare(bc, header, nil)
 	if err != nil {
@@ -274,7 +274,7 @@ func insertBlockParamsToBlock(config *chainParams.ChainConfig, parent *types.Hea
 		Time:        params.Timestamp,
 	}
 	if config.IsCurie(number) {
-		header.BaseFee = misc.CalcBaseFee(config, parent, parentL1BaseFee)
+		header.BaseFee = misc.CalcBaseFee(config, parent, parentL1BaseFee, header.Time)
 	}
 	block := types.NewBlockWithHeader(header).WithBody(txs, nil /* uncles */)
 	return block, nil

eth/gasprice/feehistory.go

@@ -96,7 +96,8 @@ func (oracle *Oracle) processBlock(bf *blockFees, percentiles []float64, nonCong
 			return
 		}
 		l1BaseFee := fees.GetL1BaseFee(state)
-		bf.results.nextBaseFee = misc.CalcBaseFee(chainconfig, bf.header, l1BaseFee)
+		// Use bf.header.Time as the current block time to calculate the next base fee because there are cases to query historical block fees
+		bf.results.nextBaseFee = misc.CalcBaseFee(chainconfig, bf.header, l1BaseFee, bf.header.Time)
 	} else {
 		bf.results.nextBaseFee = new(big.Int)
 	}

internal/ethapi/api.go

@@ -1447,7 +1447,8 @@ func newRPCPendingTransaction(tx *types.Transaction, current *types.Header, conf
 	blockNumber := uint64(0)
 	blockTime := uint64(0)
 	if current != nil {
-		baseFee = misc.CalcBaseFee(config, current, l1BaseFee)
+		// Use time.Now() as the current block time to calculate the pending base fee.
+		baseFee = misc.CalcBaseFee(config, current, l1BaseFee, uint64(time.Now().Unix()))
 		blockNumber = current.Number.Uint64()
 		blockTime = current.Time
 	}

miner/scroll_worker.go

@@ -488,7 +488,7 @@ func (w *worker) newWork(now time.Time, parent *types.Block, reorging bool, reor
 	// Set baseFee if we are on an EIP-1559 chain
 	if w.chainConfig.IsCurie(header.Number) {
 		parentL1BaseFee := fees.GetL1BaseFee(parentState)
-		header.BaseFee = misc.CalcBaseFee(w.chainConfig, parent.Header(), parentL1BaseFee)
+		header.BaseFee = misc.CalcBaseFee(w.chainConfig, parent.Header(), parentL1BaseFee, header.Time)
 	}
 	// Only set the coinbase if our consensus engine is running (avoid spurious block rewards)
 	if w.isRunning() {

params/config.go

@@ -1033,6 +1033,16 @@ func (c *ChainConfig) CheckCompatible(newcfg *ChainConfig, height uint64) *Confi
 	return lasterr
 }
 
+// BaseFeeChangeDenominator bounds the amount the base fee can change between blocks.
+func (c *ChainConfig) BaseFeeChangeDenominator() uint64 {
+	return DefaultBaseFeeChangeDenominator
+}
+
+// ElasticityMultiplier bounds the maximum gas limit an EIP-1559 block may have.
+func (c *ChainConfig) ElasticityMultiplier() uint64 {
+	return DefaultElasticityMultiplier
+}
+
 // CheckConfigForkOrder checks that we don't "skip" any forks, geth isn't pluggable enough
 // to guarantee that forks can be implemented in a different order than on official networks
 func (c *ChainConfig) CheckConfigForkOrder() error {

params/protocol_params.go

@@ -127,9 +127,9 @@ const (
 	// Introduced in Tangerine Whistle (Eip 150)
 	CreateBySelfdestructGas uint64 = 25000
 
-	BaseFeeChangeDenominator = 8          // Bounds the amount the base fee can change between blocks.
+	DefaultBaseFeeChangeDenominator = 8        // Bounds the amount the base fee can change between blocks.
-	ElasticityMultiplier     = 2          // Bounds the maximum gas limit an EIP-1559 block may have.
+	DefaultElasticityMultiplier     = 2        // Bounds the maximum gas limit an EIP-1559 block may have.
-	InitialBaseFee           = 1000000000 // Initial base fee for EIP-1559 blocks.
+	InitialBaseFee                  = 10000000 // Initial base fee for EIP-1559 blocks.
 
 	MaxCodeSize     = 24576           // Maximum bytecode to permit for a contract
 	MaxInitCodeSize = 2 * MaxCodeSize // Maximum initcode to permit in a creation transaction and create instructions

params/version.go

@@ -24,7 +24,7 @@ import (
 const (
 	VersionMajor = 5         // Major version component of the current release
 	VersionMinor = 8         // Minor version component of the current release
-	VersionPatch = 60        // Patch version component of the current release
+	VersionPatch = 61        // Patch version component of the current release
 	VersionMeta  = "mainnet" // Version metadata to append to the version string
 )