SurfaceFlinger: expected present time directly from VSyncReactor
When SurfaceFlinger calculates what is the vsync time, it does
that by asking VSyncReactor what is next anticipated vsync from the
wake up time. To handle negative offsets (when SF wakes up more than
a vsync period before a vsync event) SF adds a vsync period
to that anticipated vsync.
This creates a race condition where the offset used at the
time of invalidate may be different than the offset used by
VSyncReactor calculated at the time of the requestNextVsync().
To fix that, we plumb the first calculated vsync time to
SurfaceFlinger.
Bug: 154303002
Test: Run app transitions and collect systrace
Change-Id: I3f2670c7b0ecb52a85fb07df6d360694b51d5d66
diff --git a/services/surfaceflinger/Scheduler/VSyncReactor.cpp b/services/surfaceflinger/Scheduler/VSyncReactor.cpp
index 2f1faac..5f0c9ce 100644
--- a/services/surfaceflinger/Scheduler/VSyncReactor.cpp
+++ b/services/surfaceflinger/Scheduler/VSyncReactor.cpp
@@ -128,7 +128,7 @@
mLastCallTime = vsynctime;
}
- mCallback->onDispSyncEvent(wakeupTime);
+ mCallback->onDispSyncEvent(wakeupTime, vsynctime);
{
std::lock_guard<std::mutex> lk(mMutex);