From 039206a9b40d2188eb735f56ee51f131555c9dd3 Mon Sep 17 00:00:00 2001
From: Adam Cohen <adamcohen@google.com>
Date: Thu, 1 Nov 2012 14:06:16 -0700
Subject: [PATCH] Pushing state persistence to a background thread

Change-Id: If776bc22c48525ba91dc7e4dd0e27de92612f2f5
---
 .../android/server/AppWidgetServiceImpl.java  | 47 ++++++++++++++-----
 1 file changed, 35 insertions(+), 12 deletions(-)

diff --git a/services/java/com/android/server/AppWidgetServiceImpl.java b/services/java/com/android/server/AppWidgetServiceImpl.java
index 6a313a00dc0a8..4f72abb102a4e 100644
--- a/services/java/com/android/server/AppWidgetServiceImpl.java
+++ b/services/java/com/android/server/AppWidgetServiceImpl.java
@@ -41,7 +41,10 @@ import android.net.Uri;
 import android.os.Binder;
 import android.os.Bundle;
 import android.os.Environment;
+import android.os.Handler;
+import android.os.HandlerThread;
 import android.os.IBinder;
+import android.os.Looper;
 import android.os.Process;
 import android.os.RemoteException;
 import android.os.SystemClock;
@@ -180,6 +183,8 @@ class AppWidgetServiceImpl {
     boolean mStateLoaded;
     int mMaxWidgetBitmapMemory;
 
+    private final Handler mSaveStateHandler;
+
     // These are for debugging only -- widgets are going missing in some rare instances
     ArrayList<Provider> mDeletedProviders = new ArrayList<Provider>();
     ArrayList<Host> mDeletedHosts = new ArrayList<Host>();
@@ -189,6 +194,10 @@ class AppWidgetServiceImpl {
         mPm = AppGlobals.getPackageManager();
         mAlarmManager = (AlarmManager) mContext.getSystemService(Context.ALARM_SERVICE);
         mUserId = userId;
+
+        HandlerThread handlerThread = new HandlerThread("AppWidgetServiceImpl -- Save state");
+        handlerThread.start();
+        mSaveStateHandler = new Handler(handlerThread.getLooper());
         computeMaximumWidgetBitmapMemory();
     }
 
@@ -236,7 +245,7 @@ class AppWidgetServiceImpl {
                         updateProvidersForPackageLocked(cn.getPackageName(), removedProviders);
                     }
                 }
-                saveStateLocked();
+                saveStateAsync();
             }
         }
     }
@@ -286,7 +295,7 @@ class AppWidgetServiceImpl {
                         providersModified |= addProvidersForPackageLocked(pkgName);
                     }
                 }
-                saveStateLocked();
+                saveStateAsync();
             }
         } else {
             Bundle extras = intent.getExtras();
@@ -297,7 +306,7 @@ class AppWidgetServiceImpl {
                     ensureStateLoadedLocked();
                     for (String pkgName : pkgList) {
                         providersModified |= removeProvidersForPackageLocked(pkgName);
-                        saveStateLocked();
+                        saveStateAsync();
                     }
                 }
             }
@@ -411,7 +420,7 @@ class AppWidgetServiceImpl {
 
     private void ensureStateLoadedLocked() {
         if (!mStateLoaded) {
-            loadAppWidgetList();
+            loadAppWidgetListLocked();
             loadStateLocked();
             mStateLoaded = true;
         }
@@ -432,7 +441,7 @@ class AppWidgetServiceImpl {
             host.instances.add(id);
             mAppWidgetIds.add(id);
 
-            saveStateLocked();
+            saveStateAsync();
             if (DBG) log("Allocating AppWidgetId for " + packageName + " host=" + hostId
                     + " id=" + appWidgetId);
             return appWidgetId;
@@ -445,7 +454,7 @@ class AppWidgetServiceImpl {
             AppWidgetId id = lookupAppWidgetIdLocked(appWidgetId);
             if (id != null) {
                 deleteAppWidgetLocked(id);
-                saveStateLocked();
+                saveStateAsync();
             }
         }
     }
@@ -457,7 +466,7 @@ class AppWidgetServiceImpl {
             Host host = lookupHostLocked(callingUid, hostId);
             if (host != null) {
                 deleteHostLocked(host);
-                saveStateLocked();
+                saveStateAsync();
             }
         }
     }
@@ -476,7 +485,7 @@ class AppWidgetServiceImpl {
                 }
             }
             if (changed) {
-                saveStateLocked();
+                saveStateAsync();
             }
         }
     }
@@ -592,7 +601,7 @@ class AppWidgetServiceImpl {
 
                 // schedule the future updates
                 registerForBroadcastsLocked(p, getAppWidgetIds(p));
-                saveStateLocked();
+                saveStateAsync();
             }
         } finally {
             Binder.restoreCallingIdentity(ident);
@@ -656,8 +665,8 @@ class AppWidgetServiceImpl {
             } else {
                 mPackagesWithBindWidgetPermission.remove(packageName);
             }
+            saveStateAsync();
         }
-        saveStateLocked();
     }
 
     // Binds to a specific RemoteViewsService
@@ -894,6 +903,20 @@ class AppWidgetServiceImpl {
         }
     }
 
+    private void saveStateAsync() {
+        mSaveStateHandler.post(mSaveStateRunnable);
+    }
+
+    private final Runnable mSaveStateRunnable = new Runnable() {
+        @Override
+        public void run() {
+            synchronized (mAppWidgetIds) {
+                ensureStateLoadedLocked();
+                saveStateLocked();
+            }
+        }
+    };
+
     public void updateAppWidgetOptions(int appWidgetId, Bundle options) {
         synchronized (mAppWidgetIds) {
             options = cloneIfLocalBinder(options);
@@ -914,7 +937,7 @@ class AppWidgetServiceImpl {
             intent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, id.appWidgetId);
             intent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_OPTIONS, id.options);
             mContext.sendBroadcastAsUser(intent, new UserHandle(mUserId));
-            saveStateLocked();
+            saveStateAsync();
         }
     }
 
@@ -1215,7 +1238,7 @@ class AppWidgetServiceImpl {
         }
     }
 
-    void loadAppWidgetList() {
+    void loadAppWidgetListLocked() {
         Intent intent = new Intent(AppWidgetManager.ACTION_APPWIDGET_UPDATE);
         try {
             List<ResolveInfo> broadcastReceivers = mPm.queryIntentReceivers(intent,