SF: avoid dispatching close vsyncs
When the vsync period changes, the next vsync callback might be targeting
the same vsync event, that now has a newer time based on the current
period. This means that the client might be woken up for 2 frames within
the same vsync. This change tries to avoid that by making sure that the
vsync callbacks are at least a vsync period apart minus a safe distance.
Test: new unit test
Bug: 235566681
Change-Id: Ifb9b3f8b726976452d5131c8b758d1d5ca0e3639
diff --git a/services/surfaceflinger/Scheduler/VSyncDispatchTimerQueue.h b/services/surfaceflinger/Scheduler/VSyncDispatchTimerQueue.h
index 4923031..4f2f87a 100644
--- a/services/surfaceflinger/Scheduler/VSyncDispatchTimerQueue.h
+++ b/services/surfaceflinger/Scheduler/VSyncDispatchTimerQueue.h
@@ -84,6 +84,8 @@
void dump(std::string& result) const;
private:
+ nsecs_t adjustVsyncIfNeeded(VSyncTracker& tracker, nsecs_t nextVsyncTime) const;
+
const std::string mName;
const VSyncDispatch::Callback mCallback;