commit a6bb2bc91914e1af8394f319911cce73b57355bf
author Robert Carr <racarr@google.com> Wed Apr 08 11:03:23 2020 -0700
committer Robert Carr <racarr@google.com> Mon Apr 13 11:42:57 2020 -0700
tree b81442839108f14ad865ba2a9f83b9cdcbb99394
parent 696b6c83b15397d6c6088f5be58e5f78e998d72b

Buffer(Queue/State)Layer: Consolidate preparePerFrameCompositionState

The only difference is the BLAST implementation fails when there is
no cached buffer. While in general we expect cacheBuffers to be called
by apply() there's no reason to add more code just to fail here.
Noticed this while investigating a bug where cacheBuffers wasn't
called.

Bug: 153561718
Test: Existing tests pass
Change-Id: If1faae68ef11de3f8b37474abeff14c42af3cd57

services/surfaceflinger/BufferLayer.cpp

diff --git a/services/surfaceflinger/BufferLayer.cpp b/services/surfaceflinger/BufferLayer.cpp
index 5f90566..54cd04f 100644
--- a/services/surfaceflinger/BufferLayer.cpp
+++ b/services/surfaceflinger/BufferLayer.cpp
@@ -294,6 +294,7 @@
     auto* compositionState = editCompositionState();
     if (compositionState->sidebandStream.get()) {
         compositionState->compositionType = Hwc2::IComposerClient::Composition::SIDEBAND;
+        return;
     } else {
         // Normal buffer layers
         compositionState->hdrMetadata = mBufferInfo.mHdrMetadata;
@@ -301,6 +302,12 @@
                 ? Hwc2::IComposerClient::Composition::CURSOR
                 : Hwc2::IComposerClient::Composition::DEVICE;
     }
+
+    compositionState->buffer = mBufferInfo.mBuffer;
+    compositionState->bufferSlot = (mBufferInfo.mBufferSlot == BufferQueue::INVALID_BUFFER_SLOT)
+            ? 0
+            : mBufferInfo.mBufferSlot;
+    compositionState->acquireFence = mBufferInfo.mFence;
 }
 
 bool BufferLayer::onPreComposition(nsecs_t refreshStartTime) {