miner/worker: broadcast block immediately once sealed (bnb-chain#2576)

core/blockchain.go

@@ -1908,26 +1908,30 @@ func (bc *BlockChain) writeBlockWithState(block *types.Block, receipts []*types.
 
 // WriteBlockAndSetHead writes the given block and all associated state to the database,
 // and applies the block as the new chain head.
-func (bc *BlockChain) WriteBlockAndSetHead(block *types.Block, receipts []*types.Receipt, logs []*types.Log, state *state.StateDB, emitHeadEvent bool) (status WriteStatus, err error) {
+func (bc *BlockChain) WriteBlockAndSetHead(block *types.Block, receipts []*types.Receipt, logs []*types.Log, state *state.StateDB, emitHeadEvent bool, mux *event.TypeMux) (status WriteStatus, err error) {
 	if !bc.chainmu.TryLock() {
 		return NonStatTy, errChainStopped
 	}
 	defer bc.chainmu.Unlock()
 
-	return bc.writeBlockAndSetHead(block, receipts, logs, state, emitHeadEvent)
+	return bc.writeBlockAndSetHead(block, receipts, logs, state, emitHeadEvent, mux)
 }
 
 // writeBlockAndSetHead is the internal implementation of WriteBlockAndSetHead.
 // This function expects the chain mutex to be held.
-func (bc *BlockChain) writeBlockAndSetHead(block *types.Block, receipts []*types.Receipt, logs []*types.Log, state *state.StateDB, emitHeadEvent bool) (status WriteStatus, err error) {
-	if err := bc.writeBlockWithState(block, receipts, state); err != nil {
-		return NonStatTy, err
-	}
+func (bc *BlockChain) writeBlockAndSetHead(block *types.Block, receipts []*types.Receipt, logs []*types.Log, state *state.StateDB, emitHeadEvent bool, mux *event.TypeMux) (status WriteStatus, err error) {
 	currentBlock := bc.CurrentBlock()
 	reorg, err := bc.forker.ReorgNeededWithFastFinality(currentBlock, block.Header())
 	if err != nil {
 		return NonStatTy, err
 	}
+	if reorg && mux != nil {
+		mux.Post(NewSealedBlockEvent{Block: block})
+	}
+
+	if err := bc.writeBlockWithState(block, receipts, state); err != nil {
+		return NonStatTy, err
+	}
 	if reorg {
 		// Reorganise the chain if the parent is not the head block
 		if block.ParentHash() != currentBlock.Hash() {
@@ -2300,7 +2304,7 @@ func (bc *BlockChain) insertChain(chain types.Blocks, setHead bool) (int, error)
 			// Don't set the head, only insert the block
 			err = bc.writeBlockWithState(block, receipts, statedb)
 		} else {
-			status, err = bc.writeBlockAndSetHead(block, receipts, logs, statedb, false)
+			status, err = bc.writeBlockAndSetHead(block, receipts, logs, statedb, false, nil)
 		}
 		if err != nil {
 			return it.index, err

core/events.go

@@ -27,7 +27,10 @@ type NewTxsEvent struct{ Txs []*types.Transaction }
 // ReannoTxsEvent is posted when a batch of local pending transactions exceed a specified duration.
 type ReannoTxsEvent struct{ Txs []*types.Transaction }
 
-// NewMinedBlockEvent is posted when a block has been imported.
+// NewSealedBlockEvent is posted when a block has been sealed.
+type NewSealedBlockEvent struct{ Block *types.Block }
+
+// NewMinedBlockEvent is posted when a block has been mined.
 type NewMinedBlockEvent struct{ Block *types.Block }
 
 // RemovedLogsEvent is posted when a reorg happens

eth/handler.go

@@ -729,7 +729,7 @@ func (h *handler) Start(maxPeers int, maxPeersPerIP int) {
 
 	// broadcast mined blocks
 	h.wg.Add(1)
-	h.minedBlockSub = h.eventMux.Subscribe(core.NewMinedBlockEvent{})
+	h.minedBlockSub = h.eventMux.Subscribe(core.NewMinedBlockEvent{}, core.NewSealedBlockEvent{})
 	go h.minedBroadcastLoop()
 
 	// start sync handlers
@@ -946,8 +946,9 @@ func (h *handler) minedBroadcastLoop() {
 			if obj == nil {
 				continue
 			}
-			if ev, ok := obj.Data.(core.NewMinedBlockEvent); ok {
-				h.BroadcastBlock(ev.Block, true)  // First propagate block to peers
+			if ev, ok := obj.Data.(core.NewSealedBlockEvent); ok {
+				h.BroadcastBlock(ev.Block, true) // Propagate block to peers
+			} else if ev, ok := obj.Data.(core.NewMinedBlockEvent); ok {
 				h.BroadcastBlock(ev.Block, false) // Only then announce to the rest
 			}
 		case <-h.stopCh:

miner/worker.go

@@ -665,7 +665,7 @@ func (w *worker) resultLoop() {
 			// Commit block and state to database.
 			task.state.SetExpectedStateRoot(block.Root())
 			start := time.Now()
-			status, err := w.chain.WriteBlockAndSetHead(block, receipts, logs, task.state, true)
+			status, err := w.chain.WriteBlockAndSetHead(block, receipts, logs, task.state, true, w.mux)
 			if status != core.CanonStatTy {
 				if err != nil {
 					log.Error("Failed writing block to chain", "err", err, "status", status)