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

1 files changed, 1 insertions, 1 deletions

diff --git a/services/surfaceflinger/RegionSamplingThread.cpp b/services/surfaceflinger/RegionSamplingThread.cpp
index 68cd84f661..9d293b7887 100644
--- a/services/surfaceflinger/RegionSamplingThread.cpp
+++ b/services/surfaceflinger/RegionSamplingThread.cpp
@@ -130,7 +130,7 @@ private:
         mVsyncListening = false;
     }
 
-    void onDispSyncEvent(nsecs_t /* when */) final {
+    void onDispSyncEvent(nsecs_t /*when*/, nsecs_t /*expectedVSyncTimestamp*/) final {
         std::unique_lock<decltype(mMutex)> lock(mMutex);
 
         if (mPhaseIntervalSetting == Phase::ZERO) {