commit ee6365b1d1704b1eedfb8f81e471b80692d8ec43
author Ady Abraham <adyabr@google.com> Wed Mar 06 14:31:45 2024 -0800
committer Ady Abraham <adyabr@google.com> Thu Mar 07 16:27:07 2024 -0800
tree 238403d2c271a705839fd795c4751e6532fca28a
parent 77b4fb1e91144f60dddc027612c237d79fe3776f

SF: flush setRenderRate when changing mode

There is no point to try to syncronize changing the render rate
if the display mode changes. This would just cause more latency
to getting the next vsync.

Bug: 328140524
Test: presubmit
Change-Id: I78a82bee01ba793890d459564ab701d257851b49

services/surfaceflinger/Scheduler/VSyncPredictor.cpp

diff --git a/services/surfaceflinger/Scheduler/VSyncPredictor.cpp b/services/surfaceflinger/Scheduler/VSyncPredictor.cpp
index 156cf99..58457d8 100644
--- a/services/surfaceflinger/Scheduler/VSyncPredictor.cpp
+++ b/services/surfaceflinger/Scheduler/VSyncPredictor.cpp
@@ -296,6 +296,10 @@
     const auto now = TimePoint::fromNs(mClock->now());
     purgeTimelines(now);
 
+    if (lastVsyncOpt && *lastVsyncOpt > timePoint) {
+        timePoint = *lastVsyncOpt;
+    }
+
     const auto model = getVSyncPredictionModelLocked();
     const auto threshold = model.slope / 2;
     std::optional<TimePoint> vsyncOpt;
@@ -352,7 +356,7 @@
     return mTimelines.back().isVSyncInPhase(model, vsync, frameRate);
 }
 
-void VSyncPredictor::setRenderRate(Fps renderRate) {
+void VSyncPredictor::setRenderRate(Fps renderRate, bool applyImmediately) {
     ATRACE_FORMAT("%s %s", __func__, to_string(renderRate).c_str());
     ALOGV("%s %s: RenderRate %s ", __func__, to_string(mId).c_str(), to_string(renderRate).c_str());
     std::lock_guard lock(mMutex);
@@ -360,8 +364,9 @@
     mRenderRateOpt = renderRate;
     const auto renderPeriodDelta =
             prevRenderRate ? prevRenderRate->getPeriodNsecs() - renderRate.getPeriodNsecs() : 0;
-    if (renderPeriodDelta > renderRate.getPeriodNsecs() &&
-        mLastCommittedVsync.ns() - mClock->now() > 2 * renderRate.getPeriodNsecs()) {
+    const bool newRenderRateIsHigher = renderPeriodDelta > renderRate.getPeriodNsecs() &&
+            mLastCommittedVsync.ns() - mClock->now() > 2 * renderRate.getPeriodNsecs();
+    if (applyImmediately || newRenderRateIsHigher) {
         mTimelines.clear();
         mLastCommittedVsync = TimePoint::fromNs(0);
     } else {