commit f129289d059e194ac2226205f8807c2e0ae8b715
author Jorim Jaggi <jjaggi@google.com> Mon Sep 10 11:58:13 2018 +0200
committer Jorim Jaggi <jjaggi@google.com> Tue Sep 18 10:51:36 2018 +0000
tree 05bec38723b94aaca9e1b29d36ede05805b5646f
parent b11b75ac50a40378973d48a0b7d4309db7a1cb36

Only run layout if we didn't have content

Otherwise we really don't have to do it as showing the window will
not change whether we have content or not.

Test: Reopen app, ensure less layout runs
Test: Launch activity on virtual display.

Bug: 112824998
Bug: 115577618
Change-Id: Id3bea85c93ead5e59f0456a2901378dd2c4a836f

services/core/java/com/android/server/wm/DisplayContent.java

diff --git a/services/core/java/com/android/server/wm/DisplayContent.java b/services/core/java/com/android/server/wm/DisplayContent.java
index ac65826..6c7304d 100644
--- a/services/core/java/com/android/server/wm/DisplayContent.java
+++ b/services/core/java/com/android/server/wm/DisplayContent.java
@@ -409,6 +409,9 @@
 
     private InputMonitor mInputMonitor;
 
+    /** Caches the value whether told display manager that we have content. */
+    private boolean mLastHasContent;
+
     /**
      * The input method window for this display.
      */
@@ -3092,8 +3095,9 @@
         forAllWindows(mApplySurfaceChangesTransaction, true /* traverseTopToBottom */);
         prepareSurfaces();
 
+        mLastHasContent = mTmpApplySurfaceChangesTransactionState.displayHasContent;
         mService.mDisplayManagerInternal.setDisplayProperties(mDisplayId,
-                mTmpApplySurfaceChangesTransactionState.displayHasContent,
+                mLastHasContent,
                 mTmpApplySurfaceChangesTransactionState.preferredRefreshRate,
                 mTmpApplySurfaceChangesTransactionState.preferredModeId,
                 true /* inTraversal, must call performTraversalInTrans... below */);
@@ -4267,4 +4271,11 @@
     InputMonitor getInputMonitor() {
         return mInputMonitor;
     }
+
+    /**
+     * @return Cached value whether we told display manager that we have content.
+     */
+    boolean getLastHasContent() {
+        return mLastHasContent;
+    }
 }

services/core/java/com/android/server/wm/WindowStateAnimator.java

diff --git a/services/core/java/com/android/server/wm/WindowStateAnimator.java b/services/core/java/com/android/server/wm/WindowStateAnimator.java
index fec8039..979149a 100644
--- a/services/core/java/com/android/server/wm/WindowStateAnimator.java
+++ b/services/core/java/com/android/server/wm/WindowStateAnimator.java
@@ -1176,15 +1176,17 @@
                         if (mIsWallpaper) {
                             w.dispatchWallpaperVisibility(true);
                         }
-                        // This draw means the difference between unique content and mirroring.
-                        // Run another pass through performLayout to set mHasContent in the
-                        // LogicalDisplay.
-                        mAnimator.setPendingLayoutChanges(w.getDisplayId(),
-                                FINISH_LAYOUT_REDO_ANIM);
-                        if (DEBUG_LAYOUT_REPEATS) {
-                            mService.mWindowPlacerLocked.debugLayoutRepeats(
-                                    "showSurfaceRobustlyLocked " + w,
-                                    mAnimator.getPendingLayoutChanges(w.getDisplayId()));
+                        if (!w.getDisplayContent().getLastHasContent()) {
+                            // This draw means the difference between unique content and mirroring.
+                            // Run another pass through performLayout to set mHasContent in the
+                            // LogicalDisplay.
+                            mAnimator.setPendingLayoutChanges(w.getDisplayId(),
+                                    FINISH_LAYOUT_REDO_ANIM);
+                            if (DEBUG_LAYOUT_REPEATS) {                        
+                                mService.mWindowPlacerLocked.debugLayoutRepeats(
+                                        "showSurfaceRobustlyLocked " + w,
+                                        mAnimator.getPendingLayoutChanges(w.getDisplayId()));
+                            }
                         }
                     } else {
                         w.setOrientationChanging(false);