commit b801a98e4d24f9ac106d8e5dbd52425eb29f582b
author Vishnu Nair <vishnun@google.com> Tue Nov 02 15:12:08 2021 -0700
committer Vishnu Nair <vishnun@google.com> Tue Nov 02 23:19:43 2021 +0000
tree d2862c4ee926dc2aa1be928f72ba3981ece99995
parent e6adce5936314c85b739c3a0297fe601100e6284

CompositionEngine: Update blur state correctly

Previously when blur state (blur radius or blur region) was
updated, we would recompute visible regions. This is not
necessary and triggers expensive visible region checks that
may contribute to sf missing the frame deadline.

Fix this by only triggering a visible region change if we
start or stop drawing blur. In addition, when visible region
does not change, update the blur parameters so Composition
Engine picks up the most up-to-date blur parameters.

Test: atest libcompositionengine_test
Fixes: 202589767

Change-Id: I442f190d92d6b911bb6bd9b4a440e0dcdbd7fb2e

services/surfaceflinger/Layer.cpp

diff --git a/services/surfaceflinger/Layer.cpp b/services/surfaceflinger/Layer.cpp
index f559ed0..e2f34fa 100644
--- a/services/surfaceflinger/Layer.cpp
+++ b/services/surfaceflinger/Layer.cpp
@@ -421,8 +421,6 @@
 
     compositionState->blendMode = static_cast<Hwc2::IComposerClient::BlendMode>(blendMode);
     compositionState->alpha = alpha;
-    compositionState->backgroundBlurRadius = drawingState.backgroundBlurRadius;
-    compositionState->blurRegions = drawingState.blurRegions;
     compositionState->stretchEffect = getStretchEffect();
 }
 
@@ -498,6 +496,9 @@
         compositionState->stretchEffect.hasEffect()) {
         compositionState->forceClientComposition = true;
     }
+    // If there are no visible region changes, we still need to update blur parameters.
+    compositionState->blurRegions = drawingState.blurRegions;
+    compositionState->backgroundBlurRadius = drawingState.backgroundBlurRadius;
 }
 
 void Layer::prepareCursorCompositionState() {
@@ -938,8 +939,11 @@
 
 bool Layer::setBackgroundBlurRadius(int backgroundBlurRadius) {
     if (mDrawingState.backgroundBlurRadius == backgroundBlurRadius) return false;
-
-    mDrawingState.sequence++;
+    // If we start or stop drawing blur then the layer's visibility state may change so increment
+    // the magic sequence number.
+    if (mDrawingState.backgroundBlurRadius == 0 || backgroundBlurRadius == 0) {
+        mDrawingState.sequence++;
+    }
     mDrawingState.backgroundBlurRadius = backgroundBlurRadius;
     mDrawingState.modified = true;
     setTransactionFlags(eTransactionNeeded);
@@ -972,6 +976,11 @@
 }
 
 bool Layer::setBlurRegions(const std::vector<BlurRegion>& blurRegions) {
+    // If we start or stop drawing blur then the layer's visibility state may change so increment
+    // the magic sequence number.
+    if (mDrawingState.blurRegions.size() == 0 || blurRegions.size() == 0) {
+        mDrawingState.sequence++;
+    }
     mDrawingState.blurRegions = blurRegions;
     mDrawingState.modified = true;
     setTransactionFlags(eTransactionNeeded);