From 1f6fc70ab0c6efdaa1c60dd2ced32fb6833c92e2 Mon Sep 17 00:00:00 2001
From: Dominik Laskowski <domlaskowski@google.com>
Date: Mon, 21 Mar 2022 08:34:50 -0700
Subject: SF: Fix feedback loop with refresh rate overlay

RefreshRateOverlay was refactored to use transactions instead of APIs
internal to SF. A side effect is that the overlay layer feeds back into
the frame rate detection and idle heuristics, which causes oscillation
that trends to the high refresh rate.

The transaction to setFrameRate failed to apply, as the NoVote argument
was invalid. Make it valid, such that LayerHistory::summarize skips the
overlay layer.

Do not reset the idle timer for solely NO_VOTE transactions.

Bug: 221081400
Test: flame is not stuck at 90 Hz when overlay is enabled.
Test: Same with sf.debug.show_refresh_rate_overlay_spinner
Test: SetFrameRateTest
Change-Id: I6322c1c487672b602a0f974e8ecf445633dcc3a1
---
 services/surfaceflinger/RefreshRateOverlay.cpp | 42 ++++++++++++--------------
 1 file changed, 19 insertions(+), 23 deletions(-)

(limited to 'services/surfaceflinger/RefreshRateOverlay.cpp')

diff --git a/services/surfaceflinger/RefreshRateOverlay.cpp b/services/surfaceflinger/RefreshRateOverlay.cpp
index 80aa07231f..d4435c2818 100644
--- a/services/surfaceflinger/RefreshRateOverlay.cpp
+++ b/services/surfaceflinger/RefreshRateOverlay.cpp
@@ -45,6 +45,15 @@ constexpr int kDigitSpace = 16;
 constexpr int kBufferWidth = 4 * kDigitWidth + 3 * kDigitSpace;
 constexpr int kBufferHeight = kDigitHeight;
 
+SurfaceComposerClient::Transaction createTransaction(const sp<SurfaceControl>& surface) {
+    constexpr float kFrameRate = 0.f;
+    constexpr int8_t kCompatibility = ANATIVEWINDOW_FRAME_RATE_NO_VOTE;
+    constexpr int8_t kSeamlessness = ANATIVEWINDOW_CHANGE_FRAME_RATE_ONLY_IF_SEAMLESS;
+
+    return SurfaceComposerClient::Transaction().setFrameRate(surface, kFrameRate, kCompatibility,
+                                                             kSeamlessness);
+}
+
 } // namespace
 
 void RefreshRateOverlay::SevenSegmentDrawer::drawSegment(Segment segment, int left, SkColor color,
@@ -213,12 +222,7 @@ RefreshRateOverlay::RefreshRateOverlay(FpsRange fpsRange, bool showSpinner)
         return;
     }
 
-    constexpr float kFrameRate = 0.f;
-    constexpr int8_t kCompatibility = static_cast<int8_t>(Layer::FrameRateCompatibility::NoVote);
-    constexpr int8_t kSeamlessness = ANATIVEWINDOW_CHANGE_FRAME_RATE_ONLY_IF_SEAMLESS;
-
-    SurfaceComposerClient::Transaction()
-            .setFrameRate(mSurfaceControl, kFrameRate, kCompatibility, kSeamlessness)
+    createTransaction(mSurfaceControl)
             .setLayer(mSurfaceControl, INT32_MAX - 2)
             .setTrustedOverlay(mSurfaceControl, true)
             .apply();
@@ -243,9 +247,7 @@ auto RefreshRateOverlay::getOrCreateBuffers(Fps fps) -> const Buffers& {
         }
     }();
 
-    SurfaceComposerClient::Transaction t;
-    t.setTransform(mSurfaceControl, transform);
-    t.apply();
+    createTransaction(mSurfaceControl).setTransform(mSurfaceControl, transform).apply();
 
     BufferCache::const_iterator it = mBufferCache.find({fps.getIntValue(), transformHint});
     if (it == mBufferCache.end()) {
@@ -287,25 +289,21 @@ void RefreshRateOverlay::setViewport(ui::Size viewport) {
     Rect frame((3 * width) >> 4, height >> 5);
     frame.offsetBy(width >> 5, height >> 4);
 
-    SurfaceComposerClient::Transaction t;
-    t.setMatrix(mSurfaceControl, frame.getWidth() / static_cast<float>(kBufferWidth), 0, 0,
-                frame.getHeight() / static_cast<float>(kBufferHeight));
-    t.setPosition(mSurfaceControl, frame.left, frame.top);
-    t.apply();
+    createTransaction(mSurfaceControl)
+            .setMatrix(mSurfaceControl, frame.getWidth() / static_cast<float>(kBufferWidth), 0, 0,
+                       frame.getHeight() / static_cast<float>(kBufferHeight))
+            .setPosition(mSurfaceControl, frame.left, frame.top)
+            .apply();
 }
 
 void RefreshRateOverlay::setLayerStack(ui::LayerStack stack) {
-    SurfaceComposerClient::Transaction t;
-    t.setLayerStack(mSurfaceControl, stack);
-    t.apply();
+    createTransaction(mSurfaceControl).setLayerStack(mSurfaceControl, stack).apply();
 }
 
 void RefreshRateOverlay::changeRefreshRate(Fps fps) {
     mCurrentFps = fps;
     const auto buffer = getOrCreateBuffers(fps)[mFrame];
-    SurfaceComposerClient::Transaction t;
-    t.setBuffer(mSurfaceControl, buffer);
-    t.apply();
+    createTransaction(mSurfaceControl).setBuffer(mSurfaceControl, buffer).apply();
 }
 
 void RefreshRateOverlay::animate() {
@@ -314,9 +312,7 @@ void RefreshRateOverlay::animate() {
     const auto& buffers = getOrCreateBuffers(*mCurrentFps);
     mFrame = (mFrame + 1) % buffers.size();
     const auto buffer = buffers[mFrame];
-    SurfaceComposerClient::Transaction t;
-    t.setBuffer(mSurfaceControl, buffer);
-    t.apply();
+    createTransaction(mSurfaceControl).setBuffer(mSurfaceControl, buffer).apply();
 }
 
 } // namespace android
-- 
cgit v1.2.3-59-g8ed1b