Don't queue buffer if nothing new to draw in Display
The current logic only checks if dirty is not empty, but doesn't account
for no content changing. Instead use the same logic that's in
beginFrame to compute mustRecompute and use that when determining if the
display should queue a buffer.
This fixes an issue where a Displays first few frames could be black
until the content is loaded.
Bug: 239888440
Test: First frame from screenrecord is no longer black
Change-Id: Ibb568302bf2d50db167a1f9ca76a0f37e2c65bf5
diff --git a/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/Output.h b/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/Output.h
index fc8dd8b..38a391b 100644
--- a/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/Output.h
+++ b/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/Output.h
@@ -152,6 +152,8 @@
virtual const compositionengine::CompositionEngine& getCompositionEngine() const = 0;
virtual void dumpState(std::string& out) const = 0;
+ bool mustRecompose() const;
+
private:
void dirtyEntireOutput();
void updateCompositionStateForBorder(const compositionengine::CompositionRefreshArgs&);
@@ -171,6 +173,9 @@
std::unique_ptr<ClientCompositionRequestCache> mClientCompositionRequestCache;
std::unique_ptr<planner::Planner> mPlanner;
std::unique_ptr<HwcAsyncWorker> mHwComposerAsyncWorker;
+
+ // Whether the content must be recomposed this frame.
+ bool mMustRecompose = false;
};
// This template factory function standardizes the implementation details of the
diff --git a/services/surfaceflinger/CompositionEngine/src/Display.cpp b/services/surfaceflinger/CompositionEngine/src/Display.cpp
index 09adaed..d359424 100644
--- a/services/surfaceflinger/CompositionEngine/src/Display.cpp
+++ b/services/surfaceflinger/CompositionEngine/src/Display.cpp
@@ -421,7 +421,7 @@
// 1) It is being handled by hardware composer, which may need this to
// keep its virtual display state machine in sync, or
// 2) There is work to be done (the dirty region isn't empty)
- if (GpuVirtualDisplayId::tryCast(mId) && getDirtyRegion().isEmpty()) {
+ if (GpuVirtualDisplayId::tryCast(mId) && !mustRecompose()) {
ALOGV("Skipping display composition");
return;
}
diff --git a/services/surfaceflinger/CompositionEngine/src/Output.cpp b/services/surfaceflinger/CompositionEngine/src/Output.cpp
index 6edc00f..993b8ef 100644
--- a/services/surfaceflinger/CompositionEngine/src/Output.cpp
+++ b/services/surfaceflinger/CompositionEngine/src/Output.cpp
@@ -1015,17 +1015,17 @@
// frame, then nothing more until we get new layers.
// - When a display is created with a private layer stack, we won't
// emit any black frames until a layer is added to the layer stack.
- const bool mustRecompose = dirty && !(empty && wasEmpty);
+ mMustRecompose = dirty && !(empty && wasEmpty);
const char flagPrefix[] = {'-', '+'};
static_cast<void>(flagPrefix);
- ALOGV_IF("%s: %s composition for %s (%cdirty %cempty %cwasEmpty)", __FUNCTION__,
- mustRecompose ? "doing" : "skipping", getName().c_str(), flagPrefix[dirty],
- flagPrefix[empty], flagPrefix[wasEmpty]);
+ ALOGV("%s: %s composition for %s (%cdirty %cempty %cwasEmpty)", __func__,
+ mMustRecompose ? "doing" : "skipping", getName().c_str(), flagPrefix[dirty],
+ flagPrefix[empty], flagPrefix[wasEmpty]);
- mRenderSurface->beginFrame(mustRecompose);
+ mRenderSurface->beginFrame(mMustRecompose);
- if (mustRecompose) {
+ if (mMustRecompose) {
outputState.lastCompositionHadVisibleLayers = !empty;
}
}
@@ -1631,5 +1631,9 @@
mRenderSurface->prepareFrame(state.usesClientComposition, state.usesDeviceComposition);
}
+bool Output::mustRecompose() const {
+ return mMustRecompose;
+}
+
} // namespace impl
} // namespace android::compositionengine
diff --git a/services/surfaceflinger/CompositionEngine/tests/DisplayTest.cpp b/services/surfaceflinger/CompositionEngine/tests/DisplayTest.cpp
index 51ca213..95459c0 100644
--- a/services/surfaceflinger/CompositionEngine/tests/DisplayTest.cpp
+++ b/services/surfaceflinger/CompositionEngine/tests/DisplayTest.cpp
@@ -971,16 +971,40 @@
// We expect no calls to queueBuffer if composition was skipped.
EXPECT_CALL(*renderSurface, queueBuffer(_)).Times(0);
+ EXPECT_CALL(*renderSurface, beginFrame(false));
gpuDisplay->editState().isEnabled = true;
gpuDisplay->editState().usesClientComposition = false;
gpuDisplay->editState().layerStackSpace.setContent(Rect(0, 0, 1, 1));
gpuDisplay->editState().dirtyRegion = Region::INVALID_REGION;
+ gpuDisplay->editState().lastCompositionHadVisibleLayers = true;
+ gpuDisplay->beginFrame();
gpuDisplay->finishFrame({}, std::move(mResultWithoutBuffer));
}
-TEST_F(DisplayFinishFrameTest, performsCompositionIfDirty) {
+TEST_F(DisplayFinishFrameTest, skipsCompositionIfEmpty) {
+ auto args = getDisplayCreationArgsForGpuVirtualDisplay();
+ std::shared_ptr<impl::Display> gpuDisplay = impl::createDisplay(mCompositionEngine, args);
+
+ mock::RenderSurface* renderSurface = new StrictMock<mock::RenderSurface>();
+ gpuDisplay->setRenderSurfaceForTest(std::unique_ptr<RenderSurface>(renderSurface));
+
+ // We expect no calls to queueBuffer if composition was skipped.
+ EXPECT_CALL(*renderSurface, queueBuffer(_)).Times(0);
+ EXPECT_CALL(*renderSurface, beginFrame(false));
+
+ gpuDisplay->editState().isEnabled = true;
+ gpuDisplay->editState().usesClientComposition = false;
+ gpuDisplay->editState().layerStackSpace.setContent(Rect(0, 0, 1, 1));
+ gpuDisplay->editState().dirtyRegion = Region(Rect(0, 0, 1, 1));
+ gpuDisplay->editState().lastCompositionHadVisibleLayers = false;
+
+ gpuDisplay->beginFrame();
+ gpuDisplay->finishFrame({}, std::move(mResultWithoutBuffer));
+}
+
+TEST_F(DisplayFinishFrameTest, performsCompositionIfDirtyAndNotEmpty) {
auto args = getDisplayCreationArgsForGpuVirtualDisplay();
std::shared_ptr<impl::Display> gpuDisplay = impl::createDisplay(mCompositionEngine, args);
@@ -989,11 +1013,15 @@
// We expect a single call to queueBuffer when composition is not skipped.
EXPECT_CALL(*renderSurface, queueBuffer(_)).Times(1);
+ EXPECT_CALL(*renderSurface, beginFrame(true));
gpuDisplay->editState().isEnabled = true;
gpuDisplay->editState().usesClientComposition = false;
gpuDisplay->editState().layerStackSpace.setContent(Rect(0, 0, 1, 1));
gpuDisplay->editState().dirtyRegion = Region(Rect(0, 0, 1, 1));
+ gpuDisplay->editState().lastCompositionHadVisibleLayers = true;
+
+ gpuDisplay->beginFrame();
gpuDisplay->finishFrame({}, std::move(mResultWithBuffer));
}