diff --git a/services/surfaceflinger/LayerStats.h b/services/surfaceflinger/LayerStats.h
index 7871fc6..7a190fd 100644
--- a/services/surfaceflinger/LayerStats.h
+++ b/services/surfaceflinger/LayerStats.h
@@ -38,9 +38,9 @@
 private:
     // Traverse layer tree to get all visible layers' stats
     void traverseLayerTreeStatsLocked(
-            std::vector<std::unique_ptr<LayerProtoParser::Layer>> layerTree,
-            const LayerProtoParser::LayerGlobal* layerGlobal,
-            std::vector<std::string>& layerShapeVec);
+            const std::vector<std::unique_ptr<LayerProtoParser::Layer>>& layerTree,
+            const LayerProtoParser::LayerGlobal& layerGlobal,
+            std::vector<std::string>* const outLayerShapeVec);
     // Convert layer's top-left position into 8x8 percentage of the display
     static const char* destinationLocation(int32_t location, int32_t range, bool isHorizontal);
     // Convert layer's size into 8x8 percentage of the display