diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp index 9b9867d84..01ffac29b 100644 --- a/services/surfaceflinger/SurfaceFlinger.cpp +++ b/services/surfaceflinger/SurfaceFlinger.cpp @@ -163,6 +163,9 @@ SurfaceFlinger::SurfaceFlinger() property_get("ro.bq.gpu_to_cpu_unsupported", value, "0"); mGpuToCpuSupported = !atoi(value); + property_get("debug.sf.drop_missed_frames", value, "0"); + mDropMissedFrames = atoi(value); + property_get("debug.sf.showupdates", value, "0"); mDebugRegion = atoi(value); @@ -919,12 +922,31 @@ bool SurfaceFlinger::handleMessageInvalidate() { void SurfaceFlinger::handleMessageRefresh() { ATRACE_CALL(); - preComposition(); - rebuildLayerStacks(); - setUpHWComposer(); - doDebugFlashRegions(); - doComposition(); - postComposition(); + + static nsecs_t previousExpectedPresent = 0; + nsecs_t expectedPresent = mPrimaryDispSync.computeNextRefresh(0); + static bool previousFrameMissed = false; + bool frameMissed = (expectedPresent == previousExpectedPresent); + if (frameMissed != previousFrameMissed) { + ATRACE_INT("FrameMissed", static_cast(frameMissed)); + } + previousFrameMissed = frameMissed; + + if (CC_UNLIKELY(mDropMissedFrames && frameMissed)) { + // Latch buffers, but don't send anything to HWC, then signal another + // wakeup for the next vsync + preComposition(); + repaintEverything(); + } else { + preComposition(); + rebuildLayerStacks(); + setUpHWComposer(); + doDebugFlashRegions(); + doComposition(); + postComposition(); + } + + previousExpectedPresent = mPrimaryDispSync.computeNextRefresh(0); } void SurfaceFlinger::doDebugFlashRegions() diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h index 3759a9240..b3baadd46 100644 --- a/services/surfaceflinger/SurfaceFlinger.h +++ b/services/surfaceflinger/SurfaceFlinger.h @@ -445,6 +445,7 @@ private: RenderEngine* mRenderEngine; nsecs_t mBootTime; bool mGpuToCpuSupported; + bool mDropMissedFrames; sp mEventThread; sp mSFEventThread; sp mEventControlThread;