Ensure overlapping draws won't break BLAST sync (422dd22c) · Commits · e / os / android_frameworks_base

core/java/android/view/SurfaceView.java

+57 −43

Original line number	Diff line number	Diff line
		@@ -420,8 +420,6 @@ public class SurfaceView extends View implements ViewRootImpl.SurfaceChangedCall
		final boolean useBLAST = viewRoot.useBLAST();
		viewRoot.registerRtFrameCallback(frame -> {
		try {
		final SurfaceControl.Transaction t = useBLAST ?
		viewRoot.getBLASTSyncTransaction() : new SurfaceControl.Transaction();
		synchronized (mSurfaceControlLock) {
		if (!parent.isValid()) {
		if (DEBUG) {
		@@ -443,16 +441,22 @@ public class SurfaceView extends View implements ViewRootImpl.SurfaceChangedCall
		Log.d(TAG, System.identityHashCode(this)
		+ " updateSurfaceAlpha RT: set alpha=" + alpha);
		}
		if (useBLAST) {
		synchronized (viewRoot.getBlastTransactionLock()) {
		viewRoot.getBLASTSyncTransaction()
		.setAlpha(mSurfaceControl, alpha);
		}
		} else {
		Transaction t = new SurfaceControl.Transaction();
		t.setAlpha(mSurfaceControl, alpha);
		if (!useBLAST) {
		t.deferTransactionUntil(mSurfaceControl,
		viewRoot.getRenderSurfaceControl(), frame);
		t.apply();
		}
		}
		// It's possible that mSurfaceControl is released in the UI thread before
		// the transaction completes. If that happens, an exception is thrown, which
		// must be caught immediately.
		t.apply();
		} catch (Exception e) {
		Log.e(TAG, System.identityHashCode(this)
		+ "updateSurfaceAlpha RT: Exception during surface transaction", e);
		@@ -793,23 +797,26 @@ public class SurfaceView extends View implements ViewRootImpl.SurfaceChangedCall
		final boolean useBLAST = viewRoot.useBLAST();
		viewRoot.registerRtFrameCallback(frame -> {
		try {
		final SurfaceControl.Transaction t = useBLAST
		? viewRoot.getBLASTSyncTransaction()
		: new SurfaceControl.Transaction();
		synchronized (mSurfaceControlLock) {
		if (!parent.isValid() \|\| mSurfaceControl == null) {
		return;
		}

		if (useBLAST) {
		synchronized (viewRoot.getBlastTransactionLock()) {
		updateRelativeZ(viewRoot.getBLASTSyncTransaction());
		}
		} else {
		final SurfaceControl.Transaction t = new SurfaceControl.Transaction();
		updateRelativeZ(t);
		if (!useBLAST) {
		t.deferTransactionUntil(mSurfaceControl,
		viewRoot.getRenderSurfaceControl(), frame);
		t.apply();
		}
		}
		// It's possible that mSurfaceControl is released in the UI thread before
		// the transaction completes. If that happens, an exception is thrown, which
		// must be caught immediately.
		t.apply();
		} catch (Exception e) {
		Log.e(TAG, System.identityHashCode(this)
		+ "setZOrderOnTop RT: Exception during surface transaction", e);
		@@ -1252,7 +1259,7 @@ public class SurfaceView extends View implements ViewRootImpl.SurfaceChangedCall
		private void applySurfaceTransforms(SurfaceControl surface, SurfaceControl.Transaction t,
		Rect position, long frameNumber) {
		final ViewRootImpl viewRoot = getViewRootImpl();
		if (frameNumber > 0 && viewRoot != null && !viewRoot.isDrawingToBLASTTransaction()) {
		if (frameNumber > 0 && viewRoot != null && !viewRoot.useBLAST()) {
		t.deferTransactionUntil(surface, viewRoot.getRenderSurfaceControl(),
		frameNumber);
		}
		@@ -1277,19 +1284,23 @@ public class SurfaceView extends View implements ViewRootImpl.SurfaceChangedCall
		return mRTLastReportedPosition;
		}

		private void setParentSpaceRectangle(Rect position, long frameNumber) {
		private void setParentSpaceRectangle(Transaction t, Rect position, long frameNumber) {
		final ViewRootImpl viewRoot = getViewRootImpl();
		final boolean useBLAST = viewRoot.isDrawingToBLASTTransaction();
		final SurfaceControl.Transaction t = useBLAST ? viewRoot.getBLASTSyncTransaction() :
		mRtTransaction;

		applySurfaceTransforms(mSurfaceControl, t, position, frameNumber);
		applyChildSurfaceTransaction_renderWorker(t, viewRoot.mSurface, frameNumber);
		}

		applyChildSurfaceTransaction_renderWorker(t, viewRoot.mSurface,
		frameNumber);
		private void setParentSpaceRectangle(Rect position, long frameNumber) {
		final ViewRootImpl viewRoot = getViewRootImpl();
		final boolean useBLAST = viewRoot.useBLAST();

		if (!useBLAST) {
		t.apply();
		if (useBLAST) {
		synchronized (viewRoot.getBlastTransactionLock()) {
		setParentSpaceRectangle(viewRoot.getBLASTSyncTransaction(), position, frameNumber);
		}
		} else {
		setParentSpaceRectangle(mRtTransaction, position, frameNumber);
		mRtTransaction.apply();
		}
		}

		@@ -1337,10 +1348,20 @@ public class SurfaceView extends View implements ViewRootImpl.SurfaceChangedCall
		}
		}

		private void releaseSurfaces(Transaction t) {
		if (mRtReleaseSurfaces) {
		mRtReleaseSurfaces = false;
		t.remove(mSurfaceControl);
		t.remove(mBackgroundControl);
		mSurfaceControl = null;
		mBackgroundControl = null;
		}
		}

		@Override
		public void positionLost(long frameNumber) {
		final ViewRootImpl viewRoot = getViewRootImpl();
		boolean useBLAST = viewRoot != null && viewRoot.isDrawingToBLASTTransaction();
		boolean useBLAST = viewRoot != null && viewRoot.useBLAST();
		if (DEBUG) {
		Log.d(TAG, String.format("%d windowPositionLost, frameNr = %d",
		System.identityHashCode(this), frameNumber));
		@@ -1351,38 +1372,31 @@ public class SurfaceView extends View implements ViewRootImpl.SurfaceChangedCall
		return;
		}

		final SurfaceControl.Transaction t = useBLAST ?
		(viewRoot != null ? viewRoot.getBLASTSyncTransaction() : mRtTransaction) :
		mRtTransaction;

		/**
		* positionLost can be called while UI thread is un-paused so we
		* need to hold the lock here.
		*/
		synchronized (mSurfaceControlLock) {
		if (frameNumber > 0 && viewRoot != null && !useBLAST) {
		if (viewRoot.mSurface.isValid()) {
		if (useBLAST) {
		synchronized (viewRoot.getBlastTransactionLock()) {
		viewRoot.getBLASTSyncTransaction().hide(mSurfaceControl);
		releaseSurfaces(viewRoot.getBLASTSyncTransaction());
		}
		} else {
		if (frameNumber > 0 && viewRoot != null && viewRoot.mSurface.isValid()) {
		mRtTransaction.deferTransactionUntil(mSurfaceControl,
		viewRoot.getRenderSurfaceControl(), frameNumber);
		}
		}
		t.hide(mSurfaceControl);

		if (mRtReleaseSurfaces) {
		mRtReleaseSurfaces = false;
		mRtTransaction.remove(mSurfaceControl);
		mRtTransaction.remove(mBackgroundControl);
		mSurfaceControl = null;
		mBackgroundControl = null;
		mRtTransaction.hide(mSurfaceControl);
		releaseSurfaces(mRtTransaction);
		// If we aren't using BLAST, we apply the transaction locally, otherwise we let
		// the ViewRoot apply it for us.
		// If the ViewRoot is null, we behave as if we aren't using BLAST so we need to
		// apply the transaction.
		mRtTransaction.apply();
		}
		mRtHandlingPositionUpdates = false;
		}

		// If we aren't using BLAST, we apply the transaction locally, otherise we let the ViewRoot apply it for us.
		// If the ViewRoot is null, we behave as if we aren't using BLAST so we need to apply the transaction.
		if (!useBLAST \|\| viewRoot == null) {
		mRtTransaction.apply();
		}
		}
		};

core/java/android/view/ViewRootImpl.java

+44 −43

Original line number	Diff line number	Diff line
		@@ -654,26 +654,25 @@ public final class ViewRootImpl implements ViewParent,
		int localChanges;
		}

		// If set, ViewRootImpl will call BLASTBufferQueue::setNextTransaction with
		// mRtBLASTSyncTransaction, prior to invoking draw. This provides a way
		// to redirect the buffers in to transactions.
		// If set, ViewRootImpl will request a callback from HWRender when it's ready to render the next
		// frame. This will allow VRI to call BLASTBufferQueue::setNextTransaction with
		// mRtBLASTSyncTransaction, so the next frame submitted will be added to the
		// mRtBLASTSyncTransaction instead of getting applied.
		private boolean mNextDrawUseBLASTSyncTransaction;
		// Set when calling setNextTransaction, we can't just reuse mNextDrawUseBLASTSyncTransaction
		// because, imagine this scenario:
		// 1. First draw is using BLAST, mNextDrawUseBLAST = true
		// 2. We call perform draw and are waiting on the callback
		// 3. After the first perform draw but before the first callback and the
		// second perform draw, a second draw sets mNextDrawUseBLAST = true (it already was)
		// 4. At this point the callback fires and we set mNextDrawUseBLAST = false;
		// 5. We get to performDraw and fail to sync as we intended because mNextDrawUseBLAST
		// is now false.
		// This is why we use a two-step latch with the two booleans, one consumed from
		// performDraw and one consumed from finishBLASTSync()
		private boolean mNextReportConsumeBLAST;
		// Be very careful with the threading here. This is used from the render thread while
		// the UI thread is paused and then applied and cleared from the UI thread right after
		// draw returns.
		private SurfaceControl.Transaction mRtBLASTSyncTransaction = new SurfaceControl.Transaction();

		// This is used to signal if the mRtBLASTSyncTransaction should be applied/merged. When true,
		// it indicates mRtBLASTSyncTransaction was sent to BLASTBufferQueue::setNextTransaction.
		// Therefore, in onFrameComplete, if mRtNextFrameReportConsumeWithBlast is true, that means
		// mRtBLASTSyncTransaction now contains the next buffer frame to be applied.
		private boolean mRtNextFrameReportedConsumeWithBlast;

		// Be very careful with the threading here. This is used from a thread pool generated by the
		// render thread. Therefore, it needs to be locked when updating from the thread pool since
		// multiple threads can be accessing it. It does not need to be locked when applied or merged
		// since that can only happen from the frame complete callback after the other callbacks have
		// been invoked.
		private final SurfaceControl.Transaction mRtBLASTSyncTransaction =
		new SurfaceControl.Transaction();

		// Keeps track of whether the WM requested us to use BLAST Sync when calling relayout.
		// We use this to make sure we don't send the WM transactions from an internal BLAST sync
		@@ -3783,26 +3782,29 @@ public final class ViewRootImpl implements ViewParent,
		commitCallbacks.get(i).run();
		}
		}
		});});
		});
		});
		}
		}

		try {
		if (mNextDrawUseBLASTSyncTransaction) {
		// TODO(b/149747443)
		// We aren't prepared to handle overlapping use of mRtBLASTSyncTransaction
		// so if we are BLAST syncing we make sure the previous draw has
		// totally finished.
		if (mAttachInfo.mThreadedRenderer != null) {
		mAttachInfo.mThreadedRenderer.pause();
		}

		mNextReportConsumeBLAST = true;
		mNextDrawUseBLASTSyncTransaction = false;

		// Frame callbacks will always occur after submitting draw requests and before
		// the draw actually occurs. This will ensure that we set the next transaction
		// for the frame that's about to get drawn and not on a previous frame that.
		//
		// This is thread safe since mRtNextFrameReportConsumeWithBlast will only be
		// modified in onFrameDraw and then again in onFrameComplete. This is to ensure the
		// next frame completed should be reported with the blast sync transaction.
		registerRtFrameCallback(frame -> {
		mRtNextFrameReportedConsumeWithBlast = true;
		if (mBlastBufferQueue != null) {
		// We don't need to synchronize mRtBLASTSyncTransaction here since it's not
		// being modified and only sent to BlastBufferQueue.
		mBlastBufferQueue.setNextTransaction(mRtBLASTSyncTransaction);
		}
		});
		mNextDrawUseBLASTSyncTransaction = false;
		}
		boolean canUseAsync = draw(fullRedrawNeeded);
		if (usingAsyncReport && !canUseAsync) {
		@@ -9757,9 +9759,12 @@ public final class ViewRootImpl implements ViewParent,

		private void finishBLASTSync(boolean apply) {
		mSendNextFrameToWm = false;
		if (mNextReportConsumeBLAST) {
		mNextReportConsumeBLAST = false;
		if (mRtNextFrameReportedConsumeWithBlast) {
		mRtNextFrameReportedConsumeWithBlast = false;

		// We don't need to synchronize mRtBLASTSyncTransaction here we're guaranteed that this
		// is called after all onFrameDraw and after callbacks to PositionUpdateListener.
		// Therefore, no one should be modifying this object until the next vsync.
		if (apply) {
		mRtBLASTSyncTransaction.apply();
		} else {
		@@ -9772,6 +9777,10 @@ public final class ViewRootImpl implements ViewParent,
		return mRtBLASTSyncTransaction;
		}

		Object getBlastTransactionLock() {
		return mRtBLASTSyncTransaction;
		}

		/**
		* @hide
		*/
		@@ -9799,12 +9808,4 @@ public final class ViewRootImpl implements ViewParent,
		boolean useBLAST() {
		return mUseBLASTAdapter && !mForceDisableBLAST;
		}

		/**
		* Returns true if we are about to or currently processing a draw directed
		* in to a BLAST transaction.
		*/
		boolean isDrawingToBLASTTransaction() {
		return mNextReportConsumeBLAST;
		}
		}