commit 91ac3b55b4de094ba25ecb45e04c5006b037a140
author Huihong Luo <huisinro@google.com> Thu Apr 08 11:07:41 2021 -0700
committer Huihong Luo <huisinro@google.com> Thu Apr 08 18:30:57 2021 -0700
tree 92fbb0d2cea02614589e8ae6b0fdb5b0a2e91106
parent 5ea461caa65d5fd21ae1cf9f2125481b5b3189af

Avoid duplicate rendering of the same cached override buffer

Bug: 183454078
Test: turn on layer caching, perform manual test
Change-Id: I85789afe68e9c0732436eb2f2f63afa26cc8f728

services/surfaceflinger/CompositionEngine/src/Output.cpp

diff --git a/services/surfaceflinger/CompositionEngine/src/Output.cpp b/services/surfaceflinger/CompositionEngine/src/Output.cpp
index aed3be9..af1edd1 100644
--- a/services/surfaceflinger/CompositionEngine/src/Output.cpp
+++ b/services/surfaceflinger/CompositionEngine/src/Output.cpp
@@ -1104,6 +1104,7 @@
     Region stubRegion;
 
     bool disableBlurs = false;
+    sp<GraphicBuffer> previousOverrideBuffer = nullptr;
 
     for (auto* layer : getOutputLayersOrderedByZ()) {
         const auto& layerState = layer->getState();
@@ -1153,8 +1154,14 @@
 
             std::vector<LayerFE::LayerSettings> results;
             if (layer->getState().overrideInfo.buffer != nullptr) {
-                results = layer->getOverrideCompositionList();
-                ALOGV("Replacing [%s] with override in RE", layer->getLayerFE().getDebugName());
+                if (layer->getState().overrideInfo.buffer != previousOverrideBuffer) {
+                    results = layer->getOverrideCompositionList();
+                    previousOverrideBuffer = layer->getState().overrideInfo.buffer;
+                    ALOGV("Replacing [%s] with override in RE", layer->getLayerFE().getDebugName());
+                } else {
+                    ALOGV("Skipping redundant override buffer for [%s] in RE",
+                          layer->getLayerFE().getDebugName());
+                }
             } else {
                 results = layerFE.prepareClientCompositionList(targetSettings);
                 if (realContentIsVisible && !results.empty()) {