SF: introduce debug.sf.hwc.min.duration
debug.sf.hwc.min.duration can be set for specific devices to
indicate the shortest duration hwc will take to present a frame.
This value is used by SurfaceFlinger to calculate the
earlistPresentTime used for preventing an early present.
Bug: 190842189
Bug: 188854955
Test: SF unit tests
Test: run TouchLatency with debug.sf.hwc.min.duration set to a value
Change-Id: I8ffe92e5e6b355892c6bb073229f417fb0e9588c
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index c1d28b1..73a5a57 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -2066,7 +2066,9 @@
std::chrono::milliseconds(mDebugRegion > 1 ? mDebugRegion : 0);
}
- refreshArgs.earliestPresentTime = mScheduler->getPreviousVsyncFrom(mExpectedPresentTime);
+ const auto prevVsyncTime = mScheduler->getPreviousVsyncFrom(mExpectedPresentTime);
+ const auto hwcMinWorkDuration = mVsyncConfiguration->getCurrentConfigs().hwcMinWorkDuration;
+ refreshArgs.earliestPresentTime = prevVsyncTime - hwcMinWorkDuration;
refreshArgs.nextInvalidateTime = mEventQueue->nextExpectedInvalidate();
mGeometryInvalid = false;