From 600852a5cb9a58334bbf46115780ef1968c559e3 Mon Sep 17 00:00:00 2001
From: Trung Nguyen <trung.n.k@gmail.com>
Date: Fri, 5 Oct 2018 16:28:10 -0400
Subject: [PATCH] reverted change on the core/blockchain.go

---
 core/blockchain.go | 17 +++--------------
 1 file changed, 3 insertions(+), 14 deletions(-)

diff --git a/core/blockchain.go b/core/blockchain.go
index c4515dabd..c5e50695a 100644
--- a/core/blockchain.go
+++ b/core/blockchain.go
@@ -89,10 +89,9 @@ type BlockChain struct {
 	scope         event.SubscriptionScope
 	genesisBlock  *types.Block
 
-	mu       sync.RWMutex // global mutex for locking chain operations
-	chainmu  sync.RWMutex // blockchain insertion lock
-	procmu   sync.RWMutex // block processor lock
-	insertmu sync.Mutex   // block and state insert lock
+	mu      sync.RWMutex // global mutex for locking chain operations
+	chainmu sync.RWMutex // blockchain insertion lock
+	procmu  sync.RWMutex // block processor lock
 
 	checkpoint       int          // checkpoint counts towards the new checkpoint
 	currentBlock     *types.Block // Current head of the block chain
@@ -814,16 +813,6 @@ func (bc *BlockChain) WriteBlockAndState(block *types.Block, receipts []*types.R
 	bc.wg.Add(1)
 	defer bc.wg.Done()
 
-	bc.insertmu.Lock()
-	defer bc.insertmu.Unlock()
-
-	if bc.config.IsQuorum && bc.config.Istanbul != nil {
-		if bc.GetBlockByHash(block.Hash()) != nil {
-			log.Warn("Block already inserted", "number", block.NumberU64(), "hash", block.Hash())
-			return CanonStatTy, nil
-		}
-	}
-
 	// Calculate the total difficulty of the block
 	ptd := bc.GetTd(block.ParentHash(), block.NumberU64()-1)
 	if ptd == nil {