From dc116850b4a87109d8fad15278bdba86e904363e Mon Sep 17 00:00:00 2001
From: "amalraj.manigmail.com" <amalraj.manigmail.com>
Date: Fri, 5 Oct 2018 15:28:50 +0800
Subject: [PATCH] miner, istanbul/backend : make seal async

---
 consensus/istanbul/backend/engine.go | 52 ++++++++++++++--------------
 miner/worker.go                      | 21 ++++++-----
 2 files changed, 39 insertions(+), 34 deletions(-)

diff --git a/consensus/istanbul/backend/engine.go b/consensus/istanbul/backend/engine.go
index 9ef64281b..47aba9d11 100644
--- a/consensus/istanbul/backend/engine.go
+++ b/consensus/istanbul/backend/engine.go
@@ -424,35 +424,35 @@ func (sb *backend) Seal(chain consensus.ChainReader, block *types.Block, results
 		results <- nil
 		return nil
 	}
-	go func() {
-		// get the proposed block hash and clear it if the seal() is completed.
-		sb.sealMu.Lock()
-		sb.proposedBlockHash = block.Hash()
-		clear := func() {
-			sb.proposedBlockHash = common.Hash{}
-			sb.sealMu.Unlock()
-		}
-		defer clear()
 
-		// post block into Istanbul engine
-		go sb.EventMux().Post(istanbul.RequestEvent{
-			Proposal: block,
-		})
-		for {
-			select {
-			case result := <-sb.commitCh:
-				// if the block hash and the hash from channel are the same,
-				// return the result. Otherwise, keep waiting the next hash.
-				if block.Hash() == result.Hash() {
-					results <- result
-					return
-				}
-			case <-stop:
-				results <- nil
-				return
+	// get the proposed block hash and clear it if the seal() is completed.
+	sb.sealMu.Lock()
+	sb.proposedBlockHash = block.Hash()
+	clear := func() {
+		sb.proposedBlockHash = common.Hash{}
+		sb.sealMu.Unlock()
+	}
+	defer clear()
+
+	// post block into Istanbul engine
+	go sb.EventMux().Post(istanbul.RequestEvent{
+		Proposal: block,
+	})
+	for {
+		select {
+		case result := <-sb.commitCh:
+			// if the block hash and the hash from channel are the same,
+			// return the result. Otherwise, keep waiting the next hash.
+			if block.Hash() == result.Hash() {
+				results <- result
+				return nil
 			}
+		case <-stop:
+			results <- nil
+			return nil
 		}
-	}()
+	}
+
 	return nil
 }
 
diff --git a/miner/worker.go b/miner/worker.go
index d5bf09444..5573569f1 100644
--- a/miner/worker.go
+++ b/miner/worker.go
@@ -544,9 +544,7 @@ func (w *worker) taskLoop() {
 			w.pendingMu.Lock()
 			w.pendingTasks[w.engine.SealHash(task.block.Header())] = task
 			w.pendingMu.Unlock()
-			if err := w.engine.Seal(w.chain, task.block, w.resultCh, stopCh); err != nil {
-				log.Warn("Block sealing failed", "err", err)
-			}
+			go w.seal(task.block, stopCh)
 		case <-w.exitCh:
 			interrupt()
 			return
@@ -554,6 +552,12 @@ func (w *worker) taskLoop() {
 	}
 }
 
+func (w *worker) seal(b *types.Block, stop <-chan struct{}) {
+	if err := w.engine.Seal(w.chain, b, w.resultCh, stop); err != nil {
+		log.Warn("Block sealing failed", "err", err)
+	}
+}
+
 // resultLoop is a standalone goroutine to handle sealing result submitting
 // and flush relative data to the database.
 func (w *worker) resultLoop() {
@@ -581,8 +585,9 @@ func (w *worker) resultLoop() {
 			}
 			// Different block could share same sealhash, deep copy here to prevent write-write conflict.
 			var logs     []*types.Log
+			work := w.current
 
-			for _, receipt := range append(task.receipts, task.privateReceipts...) {
+			for _, receipt := range append(work.receipts, work.privateReceipts...) {
 				// Update the block hash in all logs since it is now available and not when the
 				// receipt/log of individual transactions were created.
 				for _, log := range receipt.Logs {
@@ -590,14 +595,14 @@ func (w *worker) resultLoop() {
 				}
 			}
 
-			for _, log := range append(task.state.Logs(), task.privateState.Logs()...) {
+			for _, log := range append(work.state.Logs(), work.privateState.Logs()...) {
 				log.BlockHash = hash
 			}
 
 			// write private transacions
-			privateStateRoot, _ := task.privateState.Commit(w.config.IsEIP158(block.Number()))
+			privateStateRoot, _ := work.privateState.Commit(w.config.IsEIP158(block.Number()))
 			core.WritePrivateStateRoot(w.eth.ChainDb(), block.Root(), privateStateRoot)
-			allReceipts := mergeReceipts(task.receipts, task.privateReceipts)
+			allReceipts := mergeReceipts(work.receipts, work.privateReceipts)
 
 
 			// Commit block and state to database.
@@ -613,7 +618,7 @@ func (w *worker) resultLoop() {
 			w.mux.Post(core.NewMinedBlockEvent{Block: block})
 
 			var events []interface{}
-			logs   = append(task.state.Logs(), task.privateState.Logs()...)
+			logs   = append(work.state.Logs(), work.privateState.Logs()...)
 
 			switch stat {
 			case core.CanonStatTy: