From f0242ee76d5d6f54fcd68732cce5c98c7c085101 Mon Sep 17 00:00:00 2001
From: gary rong <garyrong0905@gmail.com>
Date: Wed, 29 Aug 2018 22:31:59 +0800
Subject: [PATCH] miner: keep the timestamp for resubmitted mining block
 (#17547)

---
 miner/worker.go | 23 +++++++++++++----------
 1 file changed, 13 insertions(+), 10 deletions(-)

diff --git a/miner/worker.go b/miner/worker.go
index 629ce5bd2..3500ca4c2 100644
--- a/miner/worker.go
+++ b/miner/worker.go
@@ -111,6 +111,7 @@ const (
 type newWorkReq struct {
 	interrupt *int32
 	noempty   bool
+	timestamp int64
 }
 
 // intervalAdjust represents a resubmitting interval adjustment.
@@ -285,6 +286,7 @@ func (w *worker) newWorkLoop(recommit time.Duration) {
 	var (
 		interrupt   *int32
 		minRecommit = recommit // minimal resubmit interval specified by user.
+		timestamp   int64      // timestamp for each round of mining.
 	)
 
 	timer := time.NewTimer(0)
@@ -296,7 +298,7 @@ func (w *worker) newWorkLoop(recommit time.Duration) {
 			atomic.StoreInt32(interrupt, s)
 		}
 		interrupt = new(int32)
-		w.newWorkCh <- &newWorkReq{interrupt: interrupt, noempty: noempty}
+		w.newWorkCh <- &newWorkReq{interrupt: interrupt, noempty: noempty, timestamp: timestamp}
 		timer.Reset(recommit)
 		atomic.StoreInt32(&w.newTxs, 0)
 	}
@@ -336,10 +338,12 @@ func (w *worker) newWorkLoop(recommit time.Duration) {
 		select {
 		case <-w.startCh:
 			clearPending(w.chain.CurrentBlock().NumberU64())
+			timestamp = time.Now().Unix()
 			commit(false, commitInterruptNewHead)
 
 		case head := <-w.chainHeadCh:
 			clearPending(head.Block.NumberU64())
+			timestamp = time.Now().Unix()
 			commit(false, commitInterruptNewHead)
 
 		case <-timer.C:
@@ -398,7 +402,7 @@ func (w *worker) mainLoop() {
 	for {
 		select {
 		case req := <-w.newWorkCh:
-			w.commitNewWork(req.interrupt, req.noempty)
+			w.commitNewWork(req.interrupt, req.noempty, req.timestamp)
 
 		case ev := <-w.chainSideCh:
 			if _, exist := w.possibleUncles[ev.Block.Hash()]; exist {
@@ -450,7 +454,7 @@ func (w *worker) mainLoop() {
 			} else {
 				// If we're mining, but nothing is being processed, wake on new transactions
 				if w.config.Clique != nil && w.config.Clique.Period == 0 {
-					w.commitNewWork(nil, false)
+					w.commitNewWork(nil, false, time.Now().Unix())
 				}
 			}
 			atomic.AddInt32(&w.newTxs, int32(len(ev.Txs)))
@@ -793,20 +797,19 @@ func (w *worker) commitTransactions(txs *types.TransactionsByPriceAndNonce, coin
 }
 
 // commitNewWork generates several new sealing tasks based on the parent block.
-func (w *worker) commitNewWork(interrupt *int32, noempty bool) {
+func (w *worker) commitNewWork(interrupt *int32, noempty bool, timestamp int64) {
 	w.mu.RLock()
 	defer w.mu.RUnlock()
 
 	tstart := time.Now()
 	parent := w.chain.CurrentBlock()
 
-	tstamp := tstart.Unix()
-	if parent.Time().Cmp(new(big.Int).SetInt64(tstamp)) >= 0 {
-		tstamp = parent.Time().Int64() + 1
+	if parent.Time().Cmp(new(big.Int).SetInt64(timestamp)) >= 0 {
+		timestamp = parent.Time().Int64() + 1
 	}
 	// this will ensure we're not going off too far in the future
-	if now := time.Now().Unix(); tstamp > now+1 {
-		wait := time.Duration(tstamp-now) * time.Second
+	if now := time.Now().Unix(); timestamp > now+1 {
+		wait := time.Duration(timestamp-now) * time.Second
 		log.Info("Mining too far in the future", "wait", common.PrettyDuration(wait))
 		time.Sleep(wait)
 	}
@@ -817,7 +820,7 @@ func (w *worker) commitNewWork(interrupt *int32, noempty bool) {
 		Number:     num.Add(num, common.Big1),
 		GasLimit:   core.CalcGasLimit(parent, w.gasFloor, w.gasCeil),
 		Extra:      w.extra,
-		Time:       big.NewInt(tstamp),
+		Time:       big.NewInt(timestamp),
 	}
 	// Only set the coinbase if our consensus engine is running (avoid spurious block rewards)
 	if w.isRunning() {