diff --git a/skynet-src/skynet_timer.c b/skynet-src/skynet_timer.c
index 489f8d09..32b71f77 100644
--- a/skynet-src/skynet_timer.c
+++ b/skynet-src/skynet_timer.c
@@ -16,6 +16,9 @@
 
 typedef void (*timer_execute_func)(void *ud,void *arg);
 
+#define LOCK(q) while (__sync_lock_test_and_set(&(q)->lock,1)) {}
+#define UNLOCK(q) __sync_lock_release(&(q)->lock);
+
 #define TIME_NEAR_SHIFT 8
 #define TIME_NEAR (1 << TIME_NEAR_SHIFT)
 #define TIME_LEVEL_SHIFT 6
@@ -50,8 +53,7 @@ struct timer {
 static struct timer * TI = NULL;
 
 static inline struct timer_node *
-link_clear(struct link_list *list)
-{
+link_clear(struct link_list *list) {
 	struct timer_node * ret = list->head.next;
 	list->head.next = 0;
 	list->tail = &(list->head);
@@ -60,23 +62,20 @@ link_clear(struct link_list *list)
 }
 
 static inline void
-link(struct link_list *list,struct timer_node *node)
-{
+link(struct link_list *list,struct timer_node *node) {
 	list->tail->next = node;
 	list->tail = node;
 	node->next=0;
 }
 
 static void
-add_node(struct timer *T,struct timer_node *node)
-{
+add_node(struct timer *T,struct timer_node *node) {
 	int time=node->expire;
 	int current_time=T->time;
 	
 	if ((time|TIME_NEAR_MASK)==(current_time|TIME_NEAR_MASK)) {
 		link(&T->near[time&TIME_NEAR_MASK],node);
-	}
-	else {
+	} else {
 		int i;
 		int mask=TIME_NEAR << TIME_LEVEL_SHIFT;
 		for (i=0;i<3;i++) {
@@ -90,21 +89,21 @@ add_node(struct timer *T,struct timer_node *node)
 }
 
 static void
-timer_add(struct timer *T,void *arg,size_t sz,int time)
-{
+timer_add(struct timer *T,void *arg,size_t sz,int time) {
 	struct timer_node *node = (struct timer_node *)skynet_malloc(sizeof(*node)+sz);
 	memcpy(node+1,arg,sz);
 
-	while (__sync_lock_test_and_set(&T->lock,1)) {};
+	LOCK(T);
 
 		node->expire=time+T->time;
 		add_node(T,node);
 
-	__sync_lock_release(&T->lock);
+	UNLOCK(T);
 }
 
 static void
 timer_shift(struct timer *T) {
+	LOCK(T);
 	int mask = TIME_NEAR;
 	int time = (++T->time) >> TIME_NEAR_SHIFT;
 	int i=0;
@@ -125,50 +124,57 @@ timer_shift(struct timer *T) {
 		time >>= TIME_LEVEL_SHIFT;
 		++i;
 	}	
+	UNLOCK(T);
+}
+
+static inline void
+dispatch_list(struct timer_node *current) {
+	do {
+		struct timer_event * event = (struct timer_event *)(current+1);
+		struct skynet_message message;
+		message.source = 0;
+		message.session = event->session;
+		message.data = NULL;
+		message.sz = PTYPE_RESPONSE << HANDLE_REMOTE_SHIFT;
+
+		skynet_context_push(event->handle, &message);
+		
+		struct timer_node * temp = current;
+		current=current->next;
+		skynet_free(temp);	
+	} while (current);
 }
 
 static inline void
 timer_execute(struct timer *T) {
+	LOCK(T);
 	int idx = T->time & TIME_NEAR_MASK;
 	
 	while (T->near[idx].head.next) {
 		struct timer_node *current = link_clear(&T->near[idx]);
-		
-		do {
-			struct timer_event * event = (struct timer_event *)(current+1);
-			struct skynet_message message;
-			message.source = 0;
-			message.session = event->session;
-			message.data = NULL;
-			message.sz = PTYPE_RESPONSE << HANDLE_REMOTE_SHIFT;
-
-			skynet_context_push(event->handle, &message);
-			
-			struct timer_node * temp = current;
-			current=current->next;
-			skynet_free(temp);	
-		} while (current);
+		UNLOCK(T);
+		// dispatch_list don't need lock T
+		dispatch_list(current);
+		LOCK(T);
 	}
+
+	UNLOCK(T);
 }
 
 static void 
-timer_update(struct timer *T)
-{
-	while (__sync_lock_test_and_set(&T->lock,1)) {};
-
+timer_update(struct timer *T) {
 	// try to dispatch timeout 0 (rare condition)
 	timer_execute(T);
 
 	// shift time first, and then dispatch timer message
 	timer_shift(T);
+
 	timer_execute(T);
 
-	__sync_lock_release(&T->lock);
 }
 
 static struct timer *
-timer_create_timer()
-{
+timer_create_timer() {
 	struct timer *r=(struct timer *)skynet_malloc(sizeof(struct timer));
 	memset(r,0,sizeof(*r));