diff --git a/libs/hwui/thread/Signal.h b/libs/hwui/thread/Signal.h
index dcf54498b9f5f..d4cfeeb29c173 100644
--- a/libs/hwui/thread/Signal.h
+++ b/libs/hwui/thread/Signal.h
@@ -30,8 +30,10 @@ public:
     ~Signal() { }
 
     void signal() {
-        Mutex::Autolock l(mLock);
-        mSignaled = true;
+        {
+            Mutex::Autolock l(mLock);
+            mSignaled = true;
+        }
         mCondition.signal(mType);
     }