From 96521fb87d19dbaa20a7355da78feec1bd4c758a Mon Sep 17 00:00:00 2001
From: Remi NGUYEN VAN <reminv@google.com>
Date: Tue, 27 Aug 2019 20:21:58 +0900
Subject: [PATCH] Run callbacks on ConnectivityService thread

Run MultinetworkPolicyTracker and DataConnectionStats callbacks on the
ConnectivityService handler thread.

Previously the callbacks would be using the SystemServer foreground
thread (Looper.myLooper()), or the broadcast thread for the
MultinetworkPolicyTracker BroadcastReceiver. This is error-prone, can
cause threading issues and makes it difficult to test the components.

Test: atest FrameworksNetTests
Change-Id: I189213dd363004abed294659165bf5430d153bba
---
 .../net/util/MultinetworkPolicyTracker.java   | 29 +++++++++++--------
 .../android/server/ConnectivityService.java   |  2 +-
 2 files changed, 18 insertions(+), 13 deletions(-)

diff --git a/core/java/android/net/util/MultinetworkPolicyTracker.java b/core/java/android/net/util/MultinetworkPolicyTracker.java
index f7e494d830..4e88149b80 100644
--- a/core/java/android/net/util/MultinetworkPolicyTracker.java
+++ b/core/java/android/net/util/MultinetworkPolicyTracker.java
@@ -64,7 +64,7 @@ public class MultinetworkPolicyTracker {
 
     private final Context mContext;
     private final Handler mHandler;
-    private final Runnable mReevaluateRunnable;
+    private final Runnable mAvoidBadWifiCallback;
     private final List<Uri> mSettingsUris;
     private final ContentResolver mResolver;
     private final SettingObserver mSettingObserver;
@@ -81,12 +81,7 @@ public class MultinetworkPolicyTracker {
     public MultinetworkPolicyTracker(Context ctx, Handler handler, Runnable avoidBadWifiCallback) {
         mContext = ctx;
         mHandler = handler;
-        mReevaluateRunnable = () -> {
-            if (updateAvoidBadWifi() && avoidBadWifiCallback != null) {
-                avoidBadWifiCallback.run();
-            }
-            updateMeteredMultipathPreference();
-        };
+        mAvoidBadWifiCallback = avoidBadWifiCallback;
         mSettingsUris = Arrays.asList(
             Settings.Global.getUriFor(NETWORK_AVOID_BAD_WIFI),
             Settings.Global.getUriFor(NETWORK_METERED_MULTIPATH_PREFERENCE));
@@ -95,15 +90,15 @@ public class MultinetworkPolicyTracker {
         mBroadcastReceiver = new BroadcastReceiver() {
             @Override
             public void onReceive(Context context, Intent intent) {
-                reevaluate();
+                reevaluateInternal();
             }
         };
 
-        TelephonyManager.from(ctx).listen(new PhoneStateListener() {
+        TelephonyManager.from(ctx).listen(new PhoneStateListener(handler.getLooper()) {
             @Override
             public void onActiveDataSubscriptionIdChanged(int subId) {
                 mActiveSubId = subId;
-                reevaluate();
+                reevaluateInternal();
             }
         }, PhoneStateListener.LISTEN_ACTIVE_DATA_SUBSCRIPTION_ID_CHANGE);
 
@@ -119,7 +114,7 @@ public class MultinetworkPolicyTracker {
         final IntentFilter intentFilter = new IntentFilter();
         intentFilter.addAction(Intent.ACTION_CONFIGURATION_CHANGED);
         mContext.registerReceiverAsUser(
-                mBroadcastReceiver, UserHandle.ALL, intentFilter, null, null);
+                mBroadcastReceiver, UserHandle.ALL, intentFilter, null, mHandler);
 
         reevaluate();
     }
@@ -164,7 +159,17 @@ public class MultinetworkPolicyTracker {
 
     @VisibleForTesting
     public void reevaluate() {
-        mHandler.post(mReevaluateRunnable);
+        mHandler.post(this::reevaluateInternal);
+    }
+
+    /**
+     * Reevaluate the settings. Must be called on the handler thread.
+     */
+    private void reevaluateInternal() {
+        if (updateAvoidBadWifi() && mAvoidBadWifiCallback != null) {
+            mAvoidBadWifiCallback.run();
+        }
+        updateMeteredMultipathPreference();
     }
 
     public boolean updateAvoidBadWifi() {
diff --git a/services/core/java/com/android/server/ConnectivityService.java b/services/core/java/com/android/server/ConnectivityService.java
index 667445b1c5..62db557833 100644
--- a/services/core/java/com/android/server/ConnectivityService.java
+++ b/services/core/java/com/android/server/ConnectivityService.java
@@ -1101,7 +1101,7 @@ public class ConnectivityService extends IConnectivityManager.Stub
         mSettingsObserver = new SettingsObserver(mContext, mHandler);
         registerSettingsCallbacks();
 
-        final DataConnectionStats dataConnectionStats = new DataConnectionStats(mContext);
+        final DataConnectionStats dataConnectionStats = new DataConnectionStats(mContext, mHandler);
         dataConnectionStats.startMonitoring();
 
         mKeepaliveTracker = new KeepaliveTracker(mContext, mHandler);