commit a8955dd64c0c7fd355a7a3973403c3ba916d6f27
author Dominik Laskowski <domlaskowski@google.com> Wed Jul 10 10:19:09 2019 -0700
committer Dominik Laskowski <domlaskowski@google.com> Fri Jul 26 10:27:49 2019 -0700
tree 6b30a3254d5d63ae0658a6a19c96eebb66510895
parent 654952126842b40699ae0bd8958b2a6eaaeb80d5

SF: Factor out expected present time computation

Compute expected present time once and pass it to traversed layers
instead of calling back into SF for each layer. This will simplify
synchronization for per-display refresh.

Also, recompute on Binder transaction, since the cached value computed
on invalidate may be stale.

Bug: 130554049
Bug: 123715322
Test: go/wm-smoke
Change-Id: I7153a728360e789dc4f97d2c39c4bdaa14183624

services/surfaceflinger/BufferQueueLayer.cpp

diff --git a/services/surfaceflinger/BufferQueueLayer.cpp b/services/surfaceflinger/BufferQueueLayer.cpp
index d685366..fe9edfe 100644
--- a/services/surfaceflinger/BufferQueueLayer.cpp
+++ b/services/surfaceflinger/BufferQueueLayer.cpp
@@ -137,13 +137,13 @@
     return mQueueItems[0].mFenceTime->getSignalTime() != Fence::SIGNAL_TIME_PENDING;
 }
 
-bool BufferQueueLayer::framePresentTimeIsCurrent() const {
+bool BufferQueueLayer::framePresentTimeIsCurrent(nsecs_t expectedPresentTime) const {
     if (!hasFrameUpdate() || isRemovedFromCurrentState()) {
         return true;
     }
 
     Mutex::Autolock lock(mQueueItemLock);
-    return mQueueItems[0].mTimestamp <= mFlinger->getExpectedPresentTime();
+    return mQueueItems[0].mTimestamp <= expectedPresentTime;
 }
 
 nsecs_t BufferQueueLayer::getDesiredPresentTime() {
@@ -196,13 +196,11 @@
     return mFormat;
 }
 
-uint64_t BufferQueueLayer::getFrameNumber() const {
+uint64_t BufferQueueLayer::getFrameNumber(nsecs_t expectedPresentTime) const {
     Mutex::Autolock lock(mQueueItemLock);
     uint64_t frameNumber = mQueueItems[0].mFrameNumber;
 
     // The head of the queue will be dropped if there are signaled and timely frames behind it
-    nsecs_t expectedPresentTime = mFlinger->getExpectedPresentTime();
-
     if (isRemovedFromCurrentState()) {
         expectedPresentTime = 0;
     }
@@ -268,7 +266,8 @@
     return mConsumer->bindTextureImage();
 }
 
-status_t BufferQueueLayer::updateTexImage(bool& recomputeVisibleRegions, nsecs_t latchTime) {
+status_t BufferQueueLayer::updateTexImage(bool& recomputeVisibleRegions, nsecs_t latchTime,
+                                          nsecs_t expectedPresentTime) {
     // This boolean is used to make sure that SurfaceFlinger's shadow copy
     // of the buffer queue isn't modified when the buffer queue is returning
     // BufferItem's that weren't actually queued. This can happen in shared
@@ -279,8 +278,6 @@
                     getProducerStickyTransform() != 0, mName.string(), mOverrideScalingMode,
                     getTransformToDisplayInverse(), mFreezeGeometryUpdates);
 
-    nsecs_t expectedPresentTime = mFlinger->getExpectedPresentTime();
-
     if (isRemovedFromCurrentState()) {
         expectedPresentTime = 0;
     }
@@ -432,7 +429,7 @@
 void BufferQueueLayer::fakeVsync() {
     mRefreshPending = false;
     bool ignored = false;
-    latchBuffer(ignored, systemTime());
+    latchBuffer(ignored, systemTime(), 0 /* expectedPresentTime */);
     usleep(16000);
     releasePendingBuffer(systemTime());
 }