diff --git a/include/gui/SurfaceTexture.h b/include/gui/SurfaceTexture.h index d7dd4d6cb..27d863de5 100644 --- a/include/gui/SurfaceTexture.h +++ b/include/gui/SurfaceTexture.h @@ -271,7 +271,8 @@ private: mRequestBufferCalled(false), mTransform(0), mScalingMode(NATIVE_WINDOW_SCALING_MODE_FREEZE), - mTimestamp(0) { + mTimestamp(0), + mFrameNumber(0) { mCrop.makeInvalid(); } @@ -340,6 +341,10 @@ private: // mTimestamp is the current timestamp for this buffer slot. This gets // to set by queueBuffer each time this slot is queued. int64_t mTimestamp; + + // mFrameNumber is the number of the queued frame for this slot. + uint64_t mFrameNumber; + }; // mSlots is the array of buffer slots that must be mirrored on the client @@ -476,6 +481,12 @@ private: // around a GL driver limitation on the number of FBO attachments, which the // browser's tile cache exceeds. const GLenum mTexTarget; + + // mFrameCounter is the free running counter, incremented for every buffer queued + // with the surface Texture. + uint64_t mFrameCounter; + + }; // ---------------------------------------------------------------------------- diff --git a/libs/gui/SurfaceTexture.cpp b/libs/gui/SurfaceTexture.cpp index ba7c35bca..ffacd5fbf 100644 --- a/libs/gui/SurfaceTexture.cpp +++ b/libs/gui/SurfaceTexture.cpp @@ -116,7 +116,8 @@ SurfaceTexture::SurfaceTexture(GLuint tex, bool allowSynchronousMode, mAllowSynchronousMode(allowSynchronousMode), mConnectedApi(NO_CONNECTED_API), mAbandoned(false), - mTexTarget(texTarget) { + mTexTarget(texTarget), + mFrameCounter(0) { // Choose a name using the PID and a process-unique ID. mName = String8::format("unnamed-%d-%d", getpid(), createProcessUniqueId()); @@ -264,7 +265,8 @@ status_t SurfaceTexture::dequeueBuffer(int *outBuf, uint32_t w, uint32_t h, status_t returnFlags(OK); - int found, foundSync; + int found = -1; + int foundSync = -1; int dequeuedCount = 0; bool tryAgain = true; while (tryAgain) { @@ -337,9 +339,14 @@ status_t SurfaceTexture::dequeueBuffer(int *outBuf, uint32_t w, uint32_t h, } } else { if (state == BufferSlot::FREE) { - foundSync = i; - found = i; - break; + /** For Asynchronous mode, we need to return the oldest of free buffers + * There is only one instance when the Framecounter overflows, this logic + * might return the earlier buffer to client. Which is a negligible impact + **/ + if (found < 0 || mSlots[i].mFrameNumber < mSlots[found].mFrameNumber) { + foundSync = i; + found = i; + } } } } @@ -531,6 +538,9 @@ status_t SurfaceTexture::queueBuffer(int buf, int64_t timestamp, mSlots[buf].mTransform = mNextTransform; mSlots[buf].mScalingMode = mNextScalingMode; mSlots[buf].mTimestamp = timestamp; + mFrameCounter++; + mSlots[buf].mFrameNumber = mFrameCounter; + mDequeueCondition.signal(); *outWidth = mDefaultWidth; @@ -564,6 +574,7 @@ void SurfaceTexture::cancelBuffer(int buf) { return; } mSlots[buf].mBufferState = BufferSlot::FREE; + mSlots[buf].mFrameNumber = 0; mDequeueCondition.signal(); } @@ -897,6 +908,7 @@ void SurfaceTexture::setFrameAvailableListener( void SurfaceTexture::freeBufferLocked(int i) { mSlots[i].mGraphicBuffer = 0; mSlots[i].mBufferState = BufferSlot::FREE; + mSlots[i].mFrameNumber = 0; if (mSlots[i].mEglImage != EGL_NO_IMAGE_KHR) { eglDestroyImageKHR(mSlots[i].mEglDisplay, mSlots[i].mEglImage); mSlots[i].mEglImage = EGL_NO_IMAGE_KHR;