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nemu/src/device/device.cc

@@ -41,11 +41,6 @@ static void timer_sig_handler(int signum) {
 }
 
 void device_update_impl() {
-    // async
-    if(device_update_flag)
-        device_update_flag = false;
-    else
-        return;
   if (update_screen_flag) {
     update_screen();
     update_screen_flag = false;
@@ -75,9 +70,16 @@ void device_update_impl() {
   }
 }
 
-void device_update() {device_update_impl();}
+void device_update() {
+#ifdef ENABLE_ASYNC_RENDER
+#else
+  if(device_update_flag.exchange(false)) {
+    device_update_impl();
+  }
+#endif
+}
 
-static void device_update_thread_daemon() {
+[[maybe_unused]] static void device_update_thread_daemon() {
   while(true) {
     if(device_update_flag.exchange(false)) {
       device_update_impl();
@@ -109,7 +111,9 @@ void init_device() {
   ret = setitimer(ITIMER_VIRTUAL, &it, NULL);
   Assert(ret == 0, "Can not set timer");
 
-  // std::thread(device_update_thread_daemon).detach();
+#ifdef ENABLE_ASYNC_RENDER
+  std::thread(device_update_thread_daemon).detach();
+#endif
 }
 #else