Plumb buffer latencies and present fences out of Composer HAL (hardware/interfaces code) (46a1fab5) · Commits · e / os / android_hardware_interfaces

graphics/composer/aidl/aidl_api/android.hardware.graphics.composer3/current/android/hardware/graphics/composer3/PresentFence.aidl

+6 −0

Original line number	Diff line number	Diff line
		@@ -36,4 +36,10 @@ package android.hardware.graphics.composer3;
		parcelable PresentFence {
		long display;
		ParcelFileDescriptor fence;
		@nullable android.hardware.graphics.composer3.PresentFence.LayerPresentFence[] layerPresentFences;
		parcelable LayerPresentFence {
		long layer;
		ParcelFileDescriptor bufferFence;
		long bufferLatencyNanos;
		}
		}

+36 −0

Original line number	Diff line number	Diff line
		@@ -27,4 +27,40 @@ parcelable PresentFence {
		* The present fence for this display.
		*/
		ParcelFileDescriptor fence;

		/**
		* A LayerPresentFence is provided by the server when a LayerCommand.pictureProfileId, specified
		* by the client, results in the buffer being rendered on the display with some latency after
		* the rest of the DisplayCommand has been rendered. This can happen due to the picture
		* processing pipeline adding additional latency for the buffer, itself. LayerPresentFences are
		* intended to arrive in the same order for each buffer submission on that layer.
		*
		* Note that this violates the SurfaceControl.Transaction API contract and therefore is only
		* allowed on TV devices that require this feature to support high quality video playback on
		* large displays.
		*/
		parcelable LayerPresentFence {
		/**
		* The layer which this fence refers to.
		*/
		long layer;

		/**
		* The present fence for the buffer contents.
		*
		* If the buffer ends up being dropped by the server and not rendered, this fence should be
		* fired at the same time as the next buffer's present fence (or the display fence if
		* picture processing for this layer was removed).
		*/
		ParcelFileDescriptor bufferFence;

		/**
		* The latency that is required for applying picture processing to the layer's buffer.
		*/
		long bufferLatencyNanos;
		}
		/**
		* The LayerPresentFences for the display.
		*/
		@nullable LayerPresentFence[] layerPresentFences;
		}

+21 −0

Original line number	Diff line number	Diff line
		@@ -145,6 +145,18 @@ class ComposerClientReader {
		return std::move(data.releasedLayers);
		}

		// Get and clear saved layer present fences.
		std::vector<PresentFence::LayerPresentFence> takeLayerPresentFences(int64_t display) {
		LOG_ALWAYS_FATAL_IF(mDisplay && display != *mDisplay);
		auto found = mReturnData.find(display);
		if (found == mReturnData.end()) {
		return {};
		}

		ReturnData& data = found->second;
		return std::move(data.layerPresentFences);
		}

		// Get and clear saved present fence.
		ndk::ScopedFileDescriptor takePresentFence(int64_t display) {
		LOG_ALWAYS_FATAL_IF(mDisplay && display != *mDisplay);
		@@ -223,6 +235,14 @@ class ComposerClientReader {
		LOG_ALWAYS_FATAL_IF(mDisplay && presentFence.display != *mDisplay);
		auto& data = mReturnData[presentFence.display];
		data.presentFence = std::move(presentFence.fence);

		if (presentFence.layerPresentFences.has_value()) {
		for (auto& optionalFence : presentFence.layerPresentFences.value()) {
		if (optionalFence.has_value()) {
		data.layerPresentFences.push_back(std::move(optionalFence.value()));
		}
		}
		}
		}

		void parseSetReleaseFences(ReleaseFences&& releaseFences) {
		@@ -260,6 +280,7 @@ class ComposerClientReader {
		DisplayRequest displayRequests;
		std::vector<ChangedCompositionLayer> changedLayers;
		ndk::ScopedFileDescriptor presentFence;
		std::vector<PresentFence::LayerPresentFence> layerPresentFences;
		std::vector<ReleaseFences::Layer> releasedLayers;
		PresentOrValidate::Result presentOrValidateState;