From 134d218f787fbfea3b64df8528c81c0a5baa0493 Mon Sep 17 00:00:00 2001
From: Vishnu Nair <vishnun@google.com>
Date: Thu, 29 Oct 2020 17:32:00 -0700
Subject: [PATCH] Add logs to track focus changes

Adds an entry to the input event log when WM requests a focus change
and to logcat when a request is dropped.

Bug: 171130500
Test: adb logcat -b events | grep input_focus
Change-Id: I48f434de1f6992a9c3dbf83f7782cd3e9b57b5af
---
 .../java/com/android/server/wm/InputMonitor.java   |  9 ++++++---
 .../android/server/wm/WindowManagerService.java    | 14 ++++++++++++++
 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/services/core/java/com/android/server/wm/InputMonitor.java b/services/core/java/com/android/server/wm/InputMonitor.java
index 470c2b1581d09..4a54196b71de9 100644
--- a/services/core/java/com/android/server/wm/InputMonitor.java
+++ b/services/core/java/com/android/server/wm/InputMonitor.java
@@ -45,6 +45,7 @@ import static android.view.WindowManager.LayoutParams.TYPE_WALLPAPER;
 import static com.android.internal.protolog.ProtoLogGroup.WM_DEBUG_FOCUS_LIGHT;
 import static com.android.server.wm.WindowManagerDebugConfig.DEBUG_INPUT;
 import static com.android.server.wm.WindowManagerDebugConfig.TAG_WM;
+import static com.android.server.wm.WindowManagerService.LOGTAG_INPUT_FOCUS;
 
 import android.graphics.Rect;
 import android.os.Handler;
@@ -54,6 +55,7 @@ import android.os.Process;
 import android.os.Trace;
 import android.os.UserHandle;
 import android.util.ArrayMap;
+import android.util.EventLog;
 import android.util.Slog;
 import android.view.InputApplicationHandle;
 import android.view.InputChannel;
@@ -503,13 +505,14 @@ final class InputMonitor {
             }
 
             if (!focus.mWinAnimator.hasSurface()) {
-                ProtoLog.d(WM_DEBUG_FOCUS_LIGHT,
-                        "Focus not requested for window=%s because it has no surface",
-                        focus);
+                Slog.v(TAG_WM, "Focus not requested for window=%" + focus
+                        + " because it has no surface.");
                 return;
             }
 
             mInputTransaction.setFocusedWindow(focus.mInputWindowHandle.token, mDisplayId);
+            EventLog.writeEvent(LOGTAG_INPUT_FOCUS,
+                    "Focus request " + focus, "reason=UpdateInputWindows");
             mDisplayContent.mLastRequestedFocus = focus;
             ProtoLog.v(WM_DEBUG_FOCUS_LIGHT, "Focus requested for window=%s", focus);
         }
diff --git a/services/core/java/com/android/server/wm/WindowManagerService.java b/services/core/java/com/android/server/wm/WindowManagerService.java
index 5bbd24918ec75..410b22a155ac6 100644
--- a/services/core/java/com/android/server/wm/WindowManagerService.java
+++ b/services/core/java/com/android/server/wm/WindowManagerService.java
@@ -206,6 +206,7 @@ import android.text.format.DateUtils;
 import android.util.ArrayMap;
 import android.util.ArraySet;
 import android.util.DisplayMetrics;
+import android.util.EventLog;
 import android.util.MergedConfiguration;
 import android.util.Slog;
 import android.util.SparseArray;
@@ -407,6 +408,7 @@ public class WindowManagerService extends IWindowManager.Stub
      */
     private static final String DISABLE_CUSTOM_TASK_ANIMATION_PROPERTY =
             "persist.wm.disable_custom_task_animation";
+    static final int LOGTAG_INPUT_FOCUS = 62001;
 
     /**
      * @see #DISABLE_CUSTOM_TASK_ANIMATION_PROPERTY
@@ -8345,6 +8347,9 @@ public class WindowManagerService extends IWindowManager.Stub
             final int displayId = embeddedWindow.mDisplayId;
             if (grantFocus) {
                 t.setFocusedWindow(targetInputToken, displayId).apply();
+                EventLog.writeEvent(LOGTAG_INPUT_FOCUS,
+                        "Focus request " + embeddedWindow.getName(),
+                        "reason=grantEmbeddedWindowFocus(true)");
             } else {
                 // Search for a new focus target
                 DisplayContent displayContent = mRoot.getDisplayContent(displayId);
@@ -8358,6 +8363,9 @@ public class WindowManagerService extends IWindowManager.Stub
                 }
                 t.requestFocusTransfer(newFocusTarget.mInputWindowHandle.token, targetInputToken,
                         displayId).apply();
+                EventLog.writeEvent(LOGTAG_INPUT_FOCUS,
+                        "Transfer focus request " + newFocusTarget,
+                        "reason=grantEmbeddedWindowFocus(false)");
             }
             ProtoLog.v(WM_DEBUG_FOCUS, "grantEmbeddedWindowFocus win=%s grantFocus=%s",
                     embeddedWindow.getName(), grantFocus);
@@ -8391,9 +8399,15 @@ public class WindowManagerService extends IWindowManager.Stub
             if (grantFocus) {
                 t.requestFocusTransfer(targetInputToken, hostWindow.mInputChannel.getToken(),
                         hostWindow.getDisplayId()).apply();
+                EventLog.writeEvent(LOGTAG_INPUT_FOCUS,
+                        "Transfer focus request " + embeddedWindow.getName(),
+                        "reason=grantEmbeddedWindowFocus(true)");
             } else {
                 t.requestFocusTransfer(hostWindow.mInputChannel.getToken(), targetInputToken,
                         hostWindow.getDisplayId()).apply();
+                EventLog.writeEvent(LOGTAG_INPUT_FOCUS,
+                        "Transfer focus request " + hostWindow,
+                        "reason=grantEmbeddedWindowFocus(false)");
             }
             ProtoLog.v(WM_DEBUG_FOCUS, "grantEmbeddedWindowFocus win=%s grantFocus=%s",
                     embeddedWindow.getName(), grantFocus);