commit d432a7c40dfa6c5498038ec652db54478df966c1
author Lloyd Pique <lpique@google.com> Fri Mar 23 16:05:31 2018 -0700
committer Lloyd Pique <lpique@google.com> Wed Mar 28 16:48:45 2018 -0700
tree a488d5cd5f6785cad4c976e1e8736d29b15c5bb9
parent 0c2de3681db029180ed13b02f090bfa1636bae1c

SF: Clean up updateTransformHint() processing.

While working on ag/3368935, an unintentional duplicate call was added
to Layer::updateTransform() from
SurfaceFlinger::handleTransactionLocked(). This patch removes the
duplicate call.

In examining the code, the update conditions also did not appear to be
set correctly. They have been adjusted so that a display change or a
significant layer change (such as a layer being added) will result in an
update.

Bug: 76223411
Test: No immediate issues observed on a Pixel XL.

Change-Id: I59220837b22ae1f76d7d9d376c1ebd24d8d14105

services/surfaceflinger/SurfaceFlinger.cpp

diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index f2cbc89..7201f19 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -2357,7 +2357,7 @@
         processDisplayHotplugEventsLocked();
     }
 
-    if (transactionFlags & (eTraversalNeeded|eDisplayTransactionNeeded)) {
+    if (transactionFlags & (eDisplayLayerStackChanged|eDisplayTransactionNeeded)) {
         // The transform hint might have changed for some layers
         // (either because a display has changed, or because a layer
         // as changed).
@@ -2404,18 +2404,18 @@
                 }
             }
 
-            if (transactionFlags & eDisplayTransactionNeeded) {
-                if (disp == nullptr) {
-                    // NOTE: TEMPORARY FIX ONLY. Real fix should cause layers to
-                    // redraw after transform hint changes. See bug 8508397.
+            if (disp == nullptr) {
+                // NOTE: TEMPORARY FIX ONLY. Real fix should cause layers to
+                // redraw after transform hint changes. See bug 8508397.
 
-                    // could be null when this layer is using a layerStack
-                    // that is not visible on any display. Also can occur at
-                    // screen off/on times.
-                    disp = getDefaultDisplayDeviceLocked();
-                }
-                layer->updateTransformHint(disp);
+                // could be null when this layer is using a layerStack
+                // that is not visible on any display. Also can occur at
+                // screen off/on times.
+                disp = getDefaultDisplayDeviceLocked();
             }
+
+            // disp can be null if there is no display available at all to get
+            // the transform hint from.
             if (disp != nullptr) {
                 layer->updateTransformHint(disp);
             }
@@ -3250,7 +3250,7 @@
             mCurrentState.layersSortedByZ.add(layer);
             // we need traversal (state changed)
             // AND transaction (list changed)
-            flags |= eTransactionNeeded|eTraversalNeeded;
+            flags |= eTransactionNeeded|eTraversalNeeded|eDisplayLayerStackChanged;
         }
     }
     if (what & layer_state_t::eDeferTransaction) {