Avoid caching EGL_SINGLE_BUFFER layers

Bug: 217776226
Test: pendemo test app updates
Change-Id: I6dde657aac1e260b5479d34120e6ca360e2616be

4 files changed, 34 insertions, 1 deletions

diff --git a/services/surfaceflinger/BufferLayer.cpp b/services/surfaceflinger/BufferLayer.cpp
index 18a6baeffe..0aca24ae70 100644
--- a/services/surfaceflinger/BufferLayer.cpp
+++ b/services/surfaceflinger/BufferLayer.cpp
@@ -311,6 +311,7 @@ void BufferLayer::preparePerFrameCompositionState() {
             ? 0
             : mBufferInfo.mBufferSlot;
     compositionState->acquireFence = mBufferInfo.mFence;
+    compositionState->frameNumber = mBufferInfo.mFrameNumber;
     compositionState->sidebandStreamHasFrame = false;
 }
 
diff --git a/services/surfaceflinger/CompositionEngine/include/compositionengine/LayerFECompositionState.h b/services/surfaceflinger/CompositionEngine/include/compositionengine/LayerFECompositionState.h
index 8bf7f8fbfa..283fe86f43 100644
--- a/services/surfaceflinger/CompositionEngine/include/compositionengine/LayerFECompositionState.h
+++ b/services/surfaceflinger/CompositionEngine/include/compositionengine/LayerFECompositionState.h
@@ -166,6 +166,7 @@ struct LayerFECompositionState {
     int bufferSlot{BufferQueue::INVALID_BUFFER_SLOT};
     sp<Fence> acquireFence = Fence::NO_FENCE;
     Region surfaceDamage;
+    uint64_t frameNumber = 0;
 
     // The handle to use for a sideband stream for this layer
     sp<NativeHandle> sidebandStream;
diff --git a/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/planner/LayerState.h b/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/planner/LayerState.h
index 14324de7ce..5fe9476a20 100644
--- a/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/planner/LayerState.h
+++ b/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/planner/LayerState.h
@@ -405,6 +405,12 @@ private:
                                                                   : nullptr)};
                     }};
 
+    // Even if the same buffer is passed to BLAST's setBuffer(), we still increment the frame
+    // number and need to treat it as if the buffer changed. Otherwise we break existing
+    // front-buffer rendering paths (such as egl's EGL_SINGLE_BUFFER).
+    OutputLayerState<uint64_t, LayerStateField::Buffer> mFrameNumber{
+            [](auto layer) { return layer->getLayerFE().getCompositionState()->frameNumber; }};
+
     int64_t mFramesSinceBufferUpdate = 0;
 
     OutputLayerState<half4, LayerStateField::SolidColor>
@@ -453,7 +459,7 @@ private:
                                       return hash;
                                   }};
 
-    static const constexpr size_t kNumNonUniqueFields = 16;
+    static const constexpr size_t kNumNonUniqueFields = 17;
 
     std::array<StateInterface*, kNumNonUniqueFields> getNonUniqueFields() {
         std::array<const StateInterface*, kNumNonUniqueFields> constFields =
@@ -472,6 +478,7 @@ private:
                 &mAlpha,        &mLayerMetadata,  &mVisibleRegion,        &mOutputDataspace,
                 &mPixelFormat,  &mColorTransform, &mCompositionType,      &mSidebandStream,
                 &mBuffer,       &mSolidColor,     &mBackgroundBlurRadius, &mBlurRegions,
+                &mFrameNumber,
         };
     }
 };
diff --git a/services/surfaceflinger/CompositionEngine/tests/planner/LayerStateTest.cpp b/services/surfaceflinger/CompositionEngine/tests/planner/LayerStateTest.cpp
index 0b1c2626a1..ae52ba21d7 100644
--- a/services/surfaceflinger/CompositionEngine/tests/planner/LayerStateTest.cpp
+++ b/services/surfaceflinger/CompositionEngine/tests/planner/LayerStateTest.cpp
@@ -359,6 +359,30 @@ TEST_F(LayerStateTest, updateBuffer) {
     EXPECT_EQ(Flags<LayerStateField>(LayerStateField::Buffer), updates);
 }
 
+TEST_F(LayerStateTest, updateBufferSingleBufferedLegacy) {
+    OutputLayerCompositionState outputLayerCompositionState;
+    LayerFECompositionState layerFECompositionState;
+    layerFECompositionState.buffer = new GraphicBuffer();
+    setupMocksForLayer(mOutputLayer, *mLayerFE, outputLayerCompositionState,
+                       layerFECompositionState);
+    mLayerState = std::make_unique<LayerState>(&mOutputLayer);
+
+    mock::OutputLayer newOutputLayer;
+    sp<mock::LayerFE> newLayerFE = sp<mock::LayerFE>::make();
+    LayerFECompositionState layerFECompositionStateTwo;
+    layerFECompositionStateTwo.buffer = new GraphicBuffer();
+    setupMocksForLayer(newOutputLayer, *newLayerFE, outputLayerCompositionState,
+                       layerFECompositionStateTwo);
+
+    for (uint64_t i = 0; i < 10; i++) {
+        layerFECompositionStateTwo.frameNumber = i;
+        setupMocksForLayer(newOutputLayer, *newLayerFE, outputLayerCompositionState,
+                           layerFECompositionStateTwo);
+        Flags<LayerStateField> updates = mLayerState->update(&newOutputLayer);
+        EXPECT_EQ(Flags<LayerStateField>(LayerStateField::Buffer), updates);
+    }
+}
+
 TEST_F(LayerStateTest, compareBuffer) {
     OutputLayerCompositionState outputLayerCompositionState;
     LayerFECompositionState layerFECompositionState;