From 50ddd5856b464e470920c67f101ddd72465eda44 Mon Sep 17 00:00:00 2001
From: Tim Murray <timmurray@google.com>
Date: Mon, 11 Jan 2021 17:00:29 -0800
Subject: [PATCH] AppWidgetServiceImpl: add mWidgetPackages lock

JobScheduler calls isBoundWidgetPackage(), but this can be extremely
slow while AppWidgetService is doing any meaningful work, causing
problems for the rest of the system. Remove that serialization by
moving mWidgetPackages behind its own lock.

Test: atest CtsAppWidgetTestCases
Bug: 161866124

Change-Id: Idae7d16d375dfd41f802ad193fa1ec939093c67a
---
 .../appwidget/AppWidgetServiceImpl.java       | 45 +++++++++++--------
 1 file changed, 26 insertions(+), 19 deletions(-)

diff --git a/services/appwidget/java/com/android/server/appwidget/AppWidgetServiceImpl.java b/services/appwidget/java/com/android/server/appwidget/AppWidgetServiceImpl.java
index 449063d957706..d4bd5adb7b250 100644
--- a/services/appwidget/java/com/android/server/appwidget/AppWidgetServiceImpl.java
+++ b/services/appwidget/java/com/android/server/appwidget/AppWidgetServiceImpl.java
@@ -222,6 +222,7 @@ class AppWidgetServiceImpl extends IAppWidgetService.Stub implements WidgetBacku
 
     private final SparseIntArray mLoadedUserIds = new SparseIntArray();
 
+    private final Object mWidgetPackagesLock = new Object();
     private final SparseArray<ArraySet<String>> mWidgetPackages = new SparseArray<>();
 
     private BackupRestoreController mBackupRestoreController;
@@ -2941,11 +2942,13 @@ class AppWidgetServiceImpl extends IAppWidgetService.Stub implements WidgetBacku
         if (widget.provider == null) return;
 
         int userId = widget.provider.getUserId();
-        ArraySet<String> packages = mWidgetPackages.get(userId);
-        if (packages == null) {
-            mWidgetPackages.put(userId, packages = new ArraySet<String>());
+        synchronized (mWidgetPackagesLock) {
+            ArraySet<String> packages = mWidgetPackages.get(userId);
+            if (packages == null) {
+                mWidgetPackages.put(userId, packages = new ArraySet<String>());
+            }
+            packages.add(widget.provider.info.provider.getPackageName());
         }
-        packages.add(widget.provider.info.provider.getPackageName());
 
         // If we are adding a widget it might be for a provider that
         // is currently masked, if so mask the widget.
@@ -2972,22 +2975,24 @@ class AppWidgetServiceImpl extends IAppWidgetService.Stub implements WidgetBacku
 
         final int userId = widget.provider.getUserId();
         final String packageName = widget.provider.info.provider.getPackageName();
-        ArraySet<String> packages = mWidgetPackages.get(userId);
-        if (packages == null) {
-            return;
-        }
-        // Check if there is any other widget with the same package name.
-        // Remove packageName if none.
-        final int N = mWidgets.size();
-        for (int i = 0; i < N; i++) {
-            Widget w = mWidgets.get(i);
-            if (w.provider == null) continue;
-            if (w.provider.getUserId() == userId
-                    && packageName.equals(w.provider.info.provider.getPackageName())) {
+        synchronized (mWidgetPackagesLock) {
+            ArraySet<String> packages = mWidgetPackages.get(userId);
+            if (packages == null) {
                 return;
             }
+            // Check if there is any other widget with the same package name.
+            // Remove packageName if none.
+            final int N = mWidgets.size();
+            for (int i = 0; i < N; i++) {
+                Widget w = mWidgets.get(i);
+                if (w.provider == null) continue;
+                if (w.provider.getUserId() == userId
+                        && packageName.equals(w.provider.info.provider.getPackageName())) {
+                    return;
+                }
+            }
+            packages.remove(packageName);
         }
-        packages.remove(packageName);
     }
 
     /**
@@ -3000,7 +3005,9 @@ class AppWidgetServiceImpl extends IAppWidgetService.Stub implements WidgetBacku
     }
 
     private void onWidgetsClearedLocked() {
-        mWidgetPackages.clear();
+        synchronized (mWidgetPackagesLock) {
+            mWidgetPackages.clear();
+        }
     }
 
     @Override
@@ -3008,7 +3015,7 @@ class AppWidgetServiceImpl extends IAppWidgetService.Stub implements WidgetBacku
         if (Binder.getCallingUid() != Process.SYSTEM_UID) {
             throw new SecurityException("Only the system process can call this");
         }
-        synchronized (mLock) {
+        synchronized (mWidgetPackagesLock) {
             final ArraySet<String> packages = mWidgetPackages.get(userId);
             if (packages != null) {
                 return packages.contains(packageName);