Recover from buffer stuffing for canned animations
Buffer stuffing occurs when SurfaceFlinger misses a frame, but the
client continues to produce buffers at the same rate, causing a
greater risk for jank to occur. Recovery is achieved for canned
animations by adjusting the animation timeline on the client side so
that SurfaceFlinger is no longer behind.
Use SF backdoor command 1045 to inject jank.
Usage: adb shell service call SurfaceFlinger 1045 f 1
Bug: b/294922229
Test: atest EventThreadTest
Test: presubmit, manually check perfetto traces
Flag: android.view.flags.buffer_stuffing_recovery
Change-Id: I38f0eb3d6ef1331e07d6022fa3a0e16c556ba06f
diff --git a/services/surfaceflinger/FrameTimeline/FrameTimeline.h b/services/surfaceflinger/FrameTimeline/FrameTimeline.h
index cffb61e..1e0940f 100644
--- a/services/surfaceflinger/FrameTimeline/FrameTimeline.h
+++ b/services/surfaceflinger/FrameTimeline/FrameTimeline.h
@@ -323,6 +323,11 @@
virtual void setSfPresent(nsecs_t sfPresentTime, const std::shared_ptr<FenceTime>& presentFence,
const std::shared_ptr<FenceTime>& gpuFence) = 0;
+ // Provides surface frames that have already been jank classified in the most recent
+ // flush of pending present fences. This allows buffer stuffing detection from SF.
+ virtual const std::vector<std::shared_ptr<frametimeline::SurfaceFrame>>& getPresentFrames()
+ const = 0;
+
// Tells FrameTimeline that a frame was committed but not composited. This is used to flush
// all the associated surface frames.
virtual void onCommitNotComposited() = 0;
@@ -497,6 +502,8 @@
void setSfWakeUp(int64_t token, nsecs_t wakeupTime, Fps refreshRate, Fps renderRate) override;
void setSfPresent(nsecs_t sfPresentTime, const std::shared_ptr<FenceTime>& presentFence,
const std::shared_ptr<FenceTime>& gpuFence = FenceTime::NO_FENCE) override;
+ const std::vector<std::shared_ptr<frametimeline::SurfaceFrame>>& getPresentFrames()
+ const override;
void onCommitNotComposited() override;
void parseArgs(const Vector<String16>& args, std::string& result) override;
void setMaxDisplayFrames(uint32_t size) override;
@@ -543,6 +550,9 @@
// display frame, this is a good starting size for the vector so that we can avoid the
// internal vector resizing that happens with push_back.
static constexpr uint32_t kNumSurfaceFramesInitial = 10;
+ // Presented surface frames that have been jank classified and can
+ // indicate of potential buffer stuffing.
+ std::vector<std::shared_ptr<frametimeline::SurfaceFrame>> mPresentFrames;
};
} // namespace impl