cmd, eth: clean up miner startup API, drop noop config field

cmd/geth/main.go

@@ -336,26 +336,18 @@ func startNode(ctx *cli.Context, stack *node.Node) {
 		if err := stack.Service(&ethereum); err != nil {
 			utils.Fatalf("Ethereum service not running: %v", err)
 		}
-		// Use a reduced number of threads if requested
-		threads := ctx.GlobalInt(utils.MinerLegacyThreadsFlag.Name)
-		if ctx.GlobalIsSet(utils.MinerThreadsFlag.Name) {
-			threads = ctx.GlobalInt(utils.MinerThreadsFlag.Name)
-		}
-		if threads > 0 {
-			type threaded interface {
-				SetThreads(threads int)
-			}
-			if th, ok := ethereum.Engine().(threaded); ok {
-				th.SetThreads(threads)
-			}
-		}
 		// Set the gas price to the limits from the CLI and start mining
 		gasprice := utils.GlobalBig(ctx, utils.MinerLegacyGasPriceFlag.Name)
 		if ctx.IsSet(utils.MinerGasPriceFlag.Name) {
 			gasprice = utils.GlobalBig(ctx, utils.MinerGasPriceFlag.Name)
 		}
 		ethereum.TxPool().SetGasPrice(gasprice)
-		if err := ethereum.StartMining(true); err != nil {
+
+		threads := ctx.GlobalInt(utils.MinerLegacyThreadsFlag.Name)
+		if ctx.GlobalIsSet(utils.MinerThreadsFlag.Name) {
+			threads = ctx.GlobalInt(utils.MinerThreadsFlag.Name)
+		}
+		if err := ethereum.StartMining(threads); err != nil {
 			utils.Fatalf("Failed to start mining: %v", err)
 		}
 	}

cmd/utils/flags.go

@@ -1130,12 +1130,6 @@ func SetEthConfig(ctx *cli.Context, stack *node.Node, cfg *eth.Config) {
 	if ctx.GlobalIsSet(CacheFlag.Name) || ctx.GlobalIsSet(CacheGCFlag.Name) {
 		cfg.TrieCache = ctx.GlobalInt(CacheFlag.Name) * ctx.GlobalInt(CacheGCFlag.Name) / 100
 	}
-	if ctx.GlobalIsSet(MinerLegacyThreadsFlag.Name) {
-		cfg.MinerThreads = ctx.GlobalInt(MinerLegacyThreadsFlag.Name)
-	}
-	if ctx.GlobalIsSet(MinerThreadsFlag.Name) {
-		cfg.MinerThreads = ctx.GlobalInt(MinerThreadsFlag.Name)
-	}
 	if ctx.GlobalIsSet(MinerNotifyFlag.Name) {
 		cfg.MinerNotify = strings.Split(ctx.GlobalString(MinerNotifyFlag.Name), ",")
 	}

eth/api.go

@@ -24,6 +24,7 @@ import (
 	"io"
 	"math/big"
 	"os"
+	"runtime"
 	"strings"
 	"time"
 
@@ -34,7 +35,6 @@ import (
 	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/internal/ethapi"
-	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/params"
 	"github.com/ethereum/go-ethereum/rlp"
 	"github.com/ethereum/go-ethereum/rpc"
@@ -94,47 +94,22 @@ func NewPrivateMinerAPI(e *Ethereum) *PrivateMinerAPI {
 	return &PrivateMinerAPI{e: e}
 }
 
-// Start the miner with the given number of threads. If threads is nil the number
-// of workers started is equal to the number of logical CPUs that are usable by
-// this process. If mining is already running, this method adjust the number of
-// threads allowed to use and updates the minimum price required by the transaction
-// pool.
+// Start starts the miner with the given number of threads. If threads is nil,
+// the number of workers started is equal to the number of logical CPUs that are
+// usable by this process. If mining is already running, this method adjust the
+// number of threads allowed to use and updates the minimum price required by the
+// transaction pool.
 func (api *PrivateMinerAPI) Start(threads *int) error {
-	// Set the number of threads if the seal engine supports it
 	if threads == nil {
-		threads = new(int)
-	} else if *threads == 0 {
-		*threads = -1 // Disable the miner from within
+		return api.e.StartMining(runtime.NumCPU())
 	}
-	type threaded interface {
-		SetThreads(threads int)
-	}
-	if th, ok := api.e.engine.(threaded); ok {
-		log.Info("Updated mining threads", "threads", *threads)
-		th.SetThreads(*threads)
-	}
-	// Start the miner and return
-	if !api.e.IsMining() {
-		// Propagate the initial price point to the transaction pool
-		api.e.lock.RLock()
-		price := api.e.gasPrice
-		api.e.lock.RUnlock()
-		api.e.txPool.SetGasPrice(price)
-		return api.e.StartMining(true)
-	}
-	return nil
+	return api.e.StartMining(*threads)
 }
 
-// Stop the miner
-func (api *PrivateMinerAPI) Stop() bool {
-	type threaded interface {
-		SetThreads(threads int)
-	}
-	if th, ok := api.e.engine.(threaded); ok {
-		th.SetThreads(-1)
-	}
+// Stop terminates the miner, both at the consensus engine level as well as at
+// the block creation level.
+func (api *PrivateMinerAPI) Stop() {
 	api.e.StopMining()
-	return true
 }
 
 // SetExtra sets the extra data string that is included when this miner mines a block.

eth/backend.go

@@ -102,12 +102,18 @@ func (s *Ethereum) AddLesServer(ls LesServer) {
 // New creates a new Ethereum object (including the
 // initialisation of the common Ethereum object)
 func New(ctx *node.ServiceContext, config *Config) (*Ethereum, error) {
+	// Ensure configuration values are compatible and sane
 	if config.SyncMode == downloader.LightSync {
 		return nil, errors.New("can't run eth.Ethereum in light sync mode, use les.LightEthereum")
 	}
 	if !config.SyncMode.IsValid() {
 		return nil, fmt.Errorf("invalid sync mode %d", config.SyncMode)
 	}
+	if config.MinerGasPrice == nil || config.MinerGasPrice.Cmp(common.Big0) <= 0 {
+		log.Warn("Sanitizing invalid miner gas price", "provided", config.MinerGasPrice, "updated", DefaultConfig.MinerGasPrice)
+		config.MinerGasPrice = new(big.Int).Set(DefaultConfig.MinerGasPrice)
+	}
+	// Assemble the Ethereum object
 	chainDb, err := CreateDB(ctx, config, "chaindata")
 	if err != nil {
 		return nil, err
@@ -333,32 +339,66 @@ func (s *Ethereum) SetEtherbase(etherbase common.Address) {
 	s.miner.SetEtherbase(etherbase)
 }
 
-func (s *Ethereum) StartMining(local bool) error {
-	eb, err := s.Etherbase()
-	if err != nil {
-		log.Error("Cannot start mining without etherbase", "err", err)
-		return fmt.Errorf("etherbase missing: %v", err)
+// StartMining starts the miner with the given number of CPU threads. If mining
+// is already running, this method adjust the number of threads allowed to use
+// and updates the minimum price required by the transaction pool.
+func (s *Ethereum) StartMining(threads int) error {
+	// Update the thread count within the consensus engine
+	type threaded interface {
+		SetThreads(threads int)
 	}
-	if clique, ok := s.engine.(*clique.Clique); ok {
-		wallet, err := s.accountManager.Find(accounts.Account{Address: eb})
-		if wallet == nil || err != nil {
-			log.Error("Etherbase account unavailable locally", "err", err)
-			return fmt.Errorf("signer missing: %v", err)
+	if th, ok := s.engine.(threaded); ok {
+		log.Info("Updated mining threads", "threads", threads)
+		if threads == 0 {
+			threads = -1 // Disable the miner from within
 		}
-		clique.Authorize(eb, wallet.SignHash)
+		th.SetThreads(threads)
 	}
-	if local {
-		// If local (CPU) mining is started, we can disable the transaction rejection
-		// mechanism introduced to speed sync times. CPU mining on mainnet is ludicrous
-		// so none will ever hit this path, whereas marking sync done on CPU mining
-		// will ensure that private networks work in single miner mode too.
+	// If the miner was not running, initialize it
+	if !s.IsMining() {
+		// Propagate the initial price point to the transaction pool
+		s.lock.RLock()
+		price := s.gasPrice
+		s.lock.RUnlock()
+		s.txPool.SetGasPrice(price)
+
+		// Configure the local mining addess
+		eb, err := s.Etherbase()
+		if err != nil {
+			log.Error("Cannot start mining without etherbase", "err", err)
+			return fmt.Errorf("etherbase missing: %v", err)
+		}
+		if clique, ok := s.engine.(*clique.Clique); ok {
+			wallet, err := s.accountManager.Find(accounts.Account{Address: eb})
+			if wallet == nil || err != nil {
+				log.Error("Etherbase account unavailable locally", "err", err)
+				return fmt.Errorf("signer missing: %v", err)
+			}
+			clique.Authorize(eb, wallet.SignHash)
+		}
+		// If mining is started, we can disable the transaction rejection mechanism
+		// introduced to speed sync times.
 		atomic.StoreUint32(&s.protocolManager.acceptTxs, 1)
+
+		go s.miner.Start(eb)
 	}
-	go s.miner.Start(eb)
 	return nil
 }
 
-func (s *Ethereum) StopMining()         { s.miner.Stop() }
+// StopMining terminates the miner, both at the consensus engine level as well as
+// at the block creation level.
+func (s *Ethereum) StopMining() {
+	// Update the thread count within the consensus engine
+	type threaded interface {
+		SetThreads(threads int)
+	}
+	if th, ok := s.engine.(threaded); ok {
+		th.SetThreads(-1)
+	}
+	// Stop the block creating itself
+	s.miner.Stop()
+}
+
 func (s *Ethereum) IsMining() bool      { return s.miner.Mining() }
 func (s *Ethereum) Miner() *miner.Miner { return s.miner }
 

eth/config.go

@@ -97,7 +97,6 @@ type Config struct {
 
 	// Mining-related options
 	Etherbase      common.Address `toml:",omitempty"`
-	MinerThreads   int            `toml:",omitempty"`
 	MinerNotify    []string       `toml:",omitempty"`
 	MinerExtraData []byte         `toml:",omitempty"`
 	MinerGasPrice  *big.Int