Reduce lock contentions in ompt/mpt.Flush()

common/trie/ompt/branch.go

@@ -117,10 +117,11 @@ func (n *branch) flush(m *mpt, nibs []byte) error {
 			return err
 		}
 	}
-	lock.Migrate()
 	if err := n.nodeBase.flushBaseInLock(m, nibs); err != nil {
 		return err
 	}
+	lock.Migrate()
+	n.state = stateFlushed
 	return nil
 }
 

common/trie/ompt/extension.go

@@ -79,8 +79,8 @@ func (n *extension) freeze() {
 }
 
 func (n *extension) flush(m *mpt, nibs []byte) error {
-	n.mutex.Lock()
-	defer n.mutex.Unlock()
+	lock := n.rlock()
+	defer lock.Unlock()
 	if n.state == stateFlushed {
 		return nil
 	}
@@ -90,6 +90,8 @@ func (n *extension) flush(m *mpt, nibs []byte) error {
 	if err := n.nodeBase.flushBaseInLock(m, nil); err != nil {
 		return err
 	}
+	lock.Migrate()
+	n.state = stateFlushed
 	return nil
 }
 

common/trie/ompt/leaf.go

@@ -77,10 +77,11 @@ func (n *leaf) flush(m *mpt, nibs []byte) error {
 	if err := n.value.Flush(); err != nil {
 		return err
 	}
-	lock.Migrate()
 	if err := n.nodeBase.flushBaseInLock(m, nil); err != nil {
 		return err
 	}
+	lock.Migrate()
+	n.state = stateFlushed
 	return nil
 }
 

common/trie/ompt/mpt.go

@@ -173,8 +173,8 @@ func (m *mpt) Get(k []byte) (trie.Object, error) {
 }
 
 func (m *mpt) Hash() []byte {
-	m.mutex.Lock()
-	defer m.mutex.Unlock()
+	m.mutex.RLock()
+	defer m.mutex.RUnlock()
 	if m.root != nil {
 		return m.root.getLink(true)
 	} else {
@@ -183,8 +183,8 @@ func (m *mpt) Hash() []byte {
 }
 
 func (m *mpt) Flush() error {
-	m.mutex.Lock()
-	defer m.mutex.Unlock()
+	m.mutex.RLock()
+	defer m.mutex.RUnlock()
 	if m.root != nil {
 		// Before flush node data to Database, We need to make sure that it
 		// builds required  data for dumping data.
@@ -415,12 +415,13 @@ func (m *mpt) Iterator() trie.IteratorForObject {
 }
 
 func (m *mpt) Filter(prefix []byte) trie.IteratorForObject {
-	m.mutex.Lock()
-	defer m.mutex.Unlock()
+	lock := RLock(&m.mutex)
+	defer lock.Unlock()
 
 	root := m.root
 	if root != nil {
-		if n, err := root.realize(m); err == nil {
+		if n, err := root.realize(m); err == nil && n != root {
+			lock.Migrate()
 			root = n
 			m.root = n
 		}

common/trie/ompt/node.go

@@ -120,7 +120,6 @@ func (n *nodeBase) flushBaseInLock(m *mpt, nibs []byte) error {
 		}
 		m.cache.Put(nibs, n.hashValue, n.serialized)
 	}
-	n.state = stateFlushed
 	return nil
 }