SurfaceFlinger: stabilize heuristic refresh rate calculation
When calculating layer's refresh rate heuristically, also store
a history of the last refresh rate calculated. We use this list to
determine how consistent is the refresh rate. If the refresh rate is
not consistent, then we keep reporting the last consistent refresh rate
and wait for the refresh rate to stabilize again.
Test: Play at 60fps video in XPlayer
Bug: 157540021
Change-Id: If3b525820d298cc5835dddf73f327501c8a18964
diff --git a/services/surfaceflinger/Scheduler/LayerInfo.h b/services/surfaceflinger/Scheduler/LayerInfo.h
index cb81ca2..820624b 100644
--- a/services/surfaceflinger/Scheduler/LayerInfo.h
+++ b/services/surfaceflinger/Scheduler/LayerInfo.h
@@ -98,9 +98,9 @@
return false;
}
- // The layer had to publish at least HISTORY_SIZE or HISTORY_TIME of updates
+ // The layer had to publish at least HISTORY_SIZE or HISTORY_DURATION of updates
if (mElements.size() < HISTORY_SIZE &&
- mElements.back() - mElements.front() < HISTORY_TIME.count()) {
+ mElements.back() - mElements.front() < HISTORY_DURATION.count()) {
return false;
}
@@ -124,7 +124,7 @@
private:
std::deque<nsecs_t> mElements;
- static constexpr std::chrono::nanoseconds HISTORY_TIME = 1s;
+ static constexpr std::chrono::nanoseconds HISTORY_DURATION = 1s;
};
friend class LayerHistoryTest;