Start target package by binding to Service, not starting Activity

This reduces the stddev for a bunch of perf tests by quite a bit
(mostly the ones that rely on starting the package).

This is because previously the target
package was made to start running by starting an Activity, which takes
up CPU cycles.

Now we start a Service and wait for it to report back that its Looper
queue is idle, then proceed.

This does seem to slightly increase the runtime for some of the tests
though...

Some test numbers (only tests that have a large difference before and
after):

Before:
registeredBroadcast_mean=1920309
registeredBroadcast_median=1724844
registeredBroadcast_stddev=559809
manifestBroadcastRunning_mean=2395693
manifestBroadcastRunning_median=2063385
manifestBroadcastRunning_stddev=809836
contentProviderRunning_mean=668463
contentProviderRunning_median=588125
contentProviderRunning_stddev=214116
bindServiceAllowOomManagement_mean=1952431
bindServiceAllowOomManagement_median=2017682
bindServiceAllowOomManagement_stddev=289311
bindServiceAlreadyBound_mean=2146257
bindServiceAlreadyBound_median=2022891
bindServiceAlreadyBound_stddev=614549
bindServiceRunning_mean=4947541
bindServiceRunning_median=4710521
bindServiceRunning_stddev=962094
startServiceProcessRunningReadUriPermission_mean=1914106
startServiceProcessRunningReadUriPermission_median=1915209
startServiceProcessRunningReadUriPermission_stddev=196136
startServiceProcessRunning_mean=2841122
startServiceProcessRunning_median=2564792
startServiceProcessRunning_stddev=684654

After:
registeredBroadcast_mean=2559587
registeredBroadcast_median=2579792
registeredBroadcast_stddev=191377
manifestBroadcastRunning_mean=2709707
manifestBroadcastRunning_median=2725365
manifestBroadcastRunning_stddev=165661
contentProviderRunning_mean=663058
contentProviderRunning_median=639062
contentProviderRunning_stddev=97864
bindServiceAllowOomManagement_mean=1899179
bindServiceAllowOomManagement_median=1932553
bindServiceAllowOomManagement_stddev=184329
bindServiceAlreadyBound_mean=2023920
bindServiceAlreadyBound_median=2051614
bindServiceAlreadyBound_stddev=159993
bindServiceRunning_mean=6683975
bindServiceRunning_median=6753699
bindServiceRunning_stddev=475811
startServiceProcessRunningReadUriPermission_mean=2388997
startServiceProcessRunningReadUriPermission_median=2405365
startServiceProcessRunningReadUriPermission_stddev=244184
startServiceProcessRunning_mean=3384101
startServiceProcessRunning_median=3388282
startServiceProcessRunning_stddev=207333

Test: m ActivityManagerPerfTestsTestApp ActivityManagerPerfTests
Test: adb install \
$OUT/data/app/ActivityManagerPerfTestsTestApp/ActivityManagerPerfTestsTestApp.apk
Test: adb install \
$OUT/data/app/ActivityManagerPerfTests/ActivityManagerPerfTests.apk
Test: adb shell am instrument -w \
com.android.frameworks.perftests.amtests/android.support.test.runner.AndroidJUnitRunner

BUG: 67460485
Change-Id: Iaaaf7d8db885cc1149e74cb7ce4b47a295ab20e4

9 files changed, 163 insertions, 94 deletions

diff --git a/tests/ActivityManagerPerfTests/test-app/AndroidManifest.xml b/tests/ActivityManagerPerfTests/test-app/AndroidManifest.xml
index 23a151c0350a..32905a96ae14 100644
--- a/tests/ActivityManagerPerfTests/test-app/AndroidManifest.xml
+++ b/tests/ActivityManagerPerfTests/test-app/AndroidManifest.xml
@@ -19,7 +19,6 @@
             android:minSdkVersion="21"
             android:targetSdkVersion="27" />
     <application android:name=".TestApplication">
-        <activity android:name=".TestActivity" android:exported="true"/>
         <provider
                 android:authorities="com.android.frameworks.perftests.amteststestapp"
                 android:name=".TestContentProvider"
@@ -33,6 +32,9 @@
             </intent-filter>
         </receiver>
         <service
+                android:name=".StartProcessService"
+                android:exported="true" />
+        <service
                 android:name=".TestService"
                 android:exported="true" />
     </application>
diff --git a/tests/ActivityManagerPerfTests/test-app/src/com/android/frameworks/perftests/amteststestapp/TestActivity.java b/tests/ActivityManagerPerfTests/test-app/src/com/android/frameworks/perftests/amteststestapp/StartProcessService.java
index 4e7bb4cc101e..054097ec207a 100644
--- a/tests/ActivityManagerPerfTests/test-app/src/com/android/frameworks/perftests/amteststestapp/TestActivity.java
+++ b/tests/ActivityManagerPerfTests/test-app/src/com/android/frameworks/perftests/amteststestapp/StartProcessService.java
@@ -16,19 +16,26 @@
 
 package com.android.frameworks.perftests.amteststestapp;
 
-import android.app.Activity;
+import android.app.Service;
+import android.content.Intent;
+import android.os.Binder;
+import android.os.IBinder;
 import android.os.Looper;
+import android.util.Log;
 
-import com.android.frameworks.perftests.am.util.Constants;
 import com.android.frameworks.perftests.am.util.Utils;
 
-public class TestActivity extends Activity {
+/**
+ * Service used to start up the target package and make sure it's running.
+ * Should be bound to, then wait for it to call the ILooperIdleCallback.
+ */
+public class StartProcessService extends Service {
     @Override
-    protected void onResume() {
-        super.onResume();
-        Looper.myQueue().addIdleHandler(() -> {
-            Utils.sendTime(getIntent(), Constants.TYPE_TARGET_PACKAGE_START);
+    public IBinder onBind(Intent intent) {
+        Looper.getMainLooper().getQueue().addIdleHandler(() -> {
+            Utils.sendLooperIdle(intent);
             return false;
         });
+        return new Binder();
     }
 }
diff --git a/tests/ActivityManagerPerfTests/tests/src/com/android/frameworks/perftests/am/tests/BasePerfTest.java b/tests/ActivityManagerPerfTests/tests/src/com/android/frameworks/perftests/am/tests/BasePerfTest.java
index cf175e00b217..58fb136ae9b3 100644
--- a/tests/ActivityManagerPerfTests/tests/src/com/android/frameworks/perftests/am/tests/BasePerfTest.java
+++ b/tests/ActivityManagerPerfTests/tests/src/com/android/frameworks/perftests/am/tests/BasePerfTest.java
@@ -16,11 +16,9 @@
 
 package com.android.frameworks.perftests.am.tests;
 
-import android.content.ComponentName;
 import android.content.Context;
 import android.content.Intent;
 import android.content.ServiceConnection;
-import android.os.IBinder;
 import android.perftests.utils.ManualBenchmarkState;
 import android.perftests.utils.PerfManualStatusReporter;
 import android.support.test.InstrumentationRegistry;
@@ -28,20 +26,16 @@ import android.support.test.InstrumentationRegistry;
 import com.android.frameworks.perftests.am.util.TargetPackageUtils;
 import com.android.frameworks.perftests.am.util.TimeReceiver;
 
-import org.junit.After;
-import org.junit.Assert;
 import org.junit.Before;
 import org.junit.Rule;
 
-import java.util.concurrent.CountDownLatch;
-import java.util.concurrent.TimeUnit;
 import java.util.function.LongSupplier;
 
 public class BasePerfTest {
     private static final String TAG = BasePerfTest.class.getSimpleName();
-    private static final long AWAIT_SERVICE_CONNECT_MS = 2000;
 
     private TimeReceiver mTimeReceiver;
+    private ServiceConnection mAliveServiceConnection;
 
     @Rule
     public PerfManualStatusReporter mPerfManualStatusReporter = new PerfManualStatusReporter();
@@ -54,11 +48,6 @@ public class BasePerfTest {
         mTimeReceiver = new TimeReceiver();
     }
 
-    @After
-    public void tearDown() {
-        TargetPackageUtils.killTargetPackage(mContext);
-    }
-
     protected void addReceivedTimeNs(String type) {
         mTimeReceiver.addTimeForTypeToQueue(type, System.nanoTime());
     }
@@ -71,46 +60,6 @@ public class BasePerfTest {
         return intent;
     }
 
-    protected ServiceConnection bindAndWaitForConnectedService() {
-        return bindAndWaitForConnectedService(0);
-    }
-
-    protected ServiceConnection bindAndWaitForConnectedService(int flags) {
-        CountDownLatch countDownLatch = new CountDownLatch(1);
-        final ServiceConnection serviceConnection = new ServiceConnection() {
-            @Override
-            public void onServiceConnected(ComponentName name, IBinder service) {
-                countDownLatch.countDown();
-            }
-
-            @Override
-            public void onServiceDisconnected(ComponentName name) {
-            }
-        };
-
-        final Intent intent = createServiceIntent();
-        final boolean success = mContext.bindService(intent, serviceConnection,
-                Context.BIND_AUTO_CREATE | flags);
-        Assert.assertTrue("Could not bind to service", success);
-
-        try {
-            boolean connectedSuccess = countDownLatch.await(AWAIT_SERVICE_CONNECT_MS,
-                    TimeUnit.MILLISECONDS);
-            Assert.assertTrue("Timeout when waiting for ServiceConnection.onServiceConnected()",
-                    connectedSuccess);
-        } catch (InterruptedException e) {
-            throw new RuntimeException(e);
-        }
-
-        return serviceConnection;
-    }
-
-    protected void unbindFromService(ServiceConnection serviceConnection) {
-        if (serviceConnection != null) {
-            mContext.unbindService(serviceConnection);
-        }
-    }
-
     protected Intent createBroadcastIntent(String action) {
         final Intent intent = new Intent(action);
         intent.addFlags(
@@ -125,11 +74,14 @@ public class BasePerfTest {
 
     private void setUpIteration() {
         mTimeReceiver.clear();
-        TargetPackageUtils.killTargetPackage(mContext);
+    }
+
+    private void tearDownIteration() {
+        TargetPackageUtils.killTargetPackage(mContext, mAliveServiceConnection);
     }
 
     protected void startTargetPackage() {
-        TargetPackageUtils.startTargetPackage(mContext, mTimeReceiver);
+        mAliveServiceConnection = TargetPackageUtils.startTargetPackage(mContext);
     }
 
     protected long getReceivedTimeNs(String type) {
@@ -142,6 +94,7 @@ public class BasePerfTest {
         while (benchmarkState.keepRunning(elapsedTimeNs)) {
             setUpIteration();
             elapsedTimeNs = func.getAsLong();
+            tearDownIteration();
         }
     }
 }
diff --git a/tests/ActivityManagerPerfTests/tests/src/com/android/frameworks/perftests/am/tests/ServiceBindPerfTest.java b/tests/ActivityManagerPerfTests/tests/src/com/android/frameworks/perftests/am/tests/ServiceBindPerfTest.java
index 6d2935a148fd..e1263db61b8b 100644
--- a/tests/ActivityManagerPerfTests/tests/src/com/android/frameworks/perftests/am/tests/ServiceBindPerfTest.java
+++ b/tests/ActivityManagerPerfTests/tests/src/com/android/frameworks/perftests/am/tests/ServiceBindPerfTest.java
@@ -25,6 +25,7 @@ import android.support.test.filters.LargeTest;
 import android.support.test.runner.AndroidJUnit4;
 
 import com.android.frameworks.perftests.am.util.Constants;
+import com.android.frameworks.perftests.am.util.TargetPackageUtils;
 
 import org.junit.Assert;
 import org.junit.Test;
@@ -75,7 +76,7 @@ public class ServiceBindPerfTest extends BasePerfTest {
                 final long endTimeNs = getReceivedTimeNs(Constants.TYPE_SERVICE_CONNECTED);
                 return endTimeNs - startTimeNs;
             } finally {
-                unbindFromService(serviceConnection);
+                TargetPackageUtils.unbindFromService(mContext, serviceConnection);
             }
         });
     }
@@ -97,7 +98,7 @@ public class ServiceBindPerfTest extends BasePerfTest {
                 final long endTimeNs = getReceivedTimeNs(Constants.TYPE_SERVICE_CONNECTED);
                 return endTimeNs - startTimeNs;
             } finally {
-                unbindFromService(serviceConnection);
+                TargetPackageUtils.unbindFromService(mContext, serviceConnection);
             }
         });
     }
@@ -112,7 +113,8 @@ public class ServiceBindPerfTest extends BasePerfTest {
             startTargetPackage();
 
             final Intent intent = createServiceIntent();
-            final ServiceConnection alreadyBoundServiceConnection = bindAndWaitForConnectedService();
+            final ServiceConnection alreadyBoundServiceConnection =
+                    TargetPackageUtils.bindAndWaitForConnectedService(mContext, intent);
 
             try {
                 final ServiceConnection serviceConnection = createServiceConnectionReportTime();
@@ -123,10 +125,10 @@ public class ServiceBindPerfTest extends BasePerfTest {
                     final long endTimeNs = getReceivedTimeNs(Constants.TYPE_SERVICE_CONNECTED);
                     return endTimeNs - startTimeNs;
                 } finally {
-                    unbindFromService(serviceConnection);
+                    TargetPackageUtils.unbindFromService(mContext, serviceConnection);
                 }
             } finally {
-                unbindFromService(alreadyBoundServiceConnection);
+                TargetPackageUtils.unbindFromService(mContext, alreadyBoundServiceConnection);
             }
         });
     }
@@ -139,8 +141,9 @@ public class ServiceBindPerfTest extends BasePerfTest {
     public void bindServiceAllowOomManagement() {
         runPerfFunction(() -> {
             final Intent intentNoOom = createServiceIntent();
-            final ServiceConnection serviceConnectionOom = bindAndWaitForConnectedService(
-                    Context.BIND_ALLOW_OOM_MANAGEMENT);
+            final ServiceConnection serviceConnectionOom =
+                    TargetPackageUtils.bindAndWaitForConnectedService(mContext, intentNoOom,
+                            Context.BIND_ALLOW_OOM_MANAGEMENT);
 
             try {
                 final ServiceConnection serviceConnectionNoOom =
@@ -152,10 +155,10 @@ public class ServiceBindPerfTest extends BasePerfTest {
 
                     return endTimeNs - startTimeNs;
                 } finally {
-                    unbindFromService(serviceConnectionNoOom);
+                    TargetPackageUtils.unbindFromService(mContext, serviceConnectionNoOom);
                 }
             } finally {
-                unbindFromService(serviceConnectionOom);
+                TargetPackageUtils.unbindFromService(mContext, serviceConnectionOom);
             }
         });
     }
diff --git a/tests/ActivityManagerPerfTests/tests/src/com/android/frameworks/perftests/am/tests/ServiceStartPerfTest.java b/tests/ActivityManagerPerfTests/tests/src/com/android/frameworks/perftests/am/tests/ServiceStartPerfTest.java
index 626ee020542d..f05f32382e53 100644
--- a/tests/ActivityManagerPerfTests/tests/src/com/android/frameworks/perftests/am/tests/ServiceStartPerfTest.java
+++ b/tests/ActivityManagerPerfTests/tests/src/com/android/frameworks/perftests/am/tests/ServiceStartPerfTest.java
@@ -23,6 +23,7 @@ import android.support.test.filters.LargeTest;
 import android.support.test.runner.AndroidJUnit4;
 
 import com.android.frameworks.perftests.am.util.Constants;
+import com.android.frameworks.perftests.am.util.TargetPackageUtils;
 
 import org.junit.Assert;
 import org.junit.Test;
@@ -86,7 +87,8 @@ public class ServiceStartPerfTest extends BasePerfTest {
     public void startServiceAlreadyBound() {
         runPerfFunction(() -> {
             final ServiceConnection alreadyBoundServiceConnection =
-                    bindAndWaitForConnectedService();
+                    TargetPackageUtils.bindAndWaitForConnectedService(mContext,
+                            createServiceIntent());
             try {
                 final Intent intent = createServiceIntent();
 
@@ -96,20 +98,21 @@ public class ServiceStartPerfTest extends BasePerfTest {
 
                 return endTimeNs - startTimeNs;
             } finally {
-                unbindFromService(alreadyBoundServiceConnection);
+                TargetPackageUtils.unbindFromService(mContext, alreadyBoundServiceConnection);
             }
         });
     }
 
     /**
      * Benchmark time from Context.startService() with FLAG_GRANT_READ_URI_PERMISSION to
-     * Service.onStartCommand() when target process is running.
+     * Service.onStartCommand() when target service is already running.
      */
     @Test
     public void startServiceProcessRunningReadUriPermission() {
         runPerfFunction(() -> {
             final ServiceConnection alreadyBoundServiceConnection =
-                    bindAndWaitForConnectedService();
+                    TargetPackageUtils.bindAndWaitForConnectedService(mContext,
+                            createServiceIntent());
             try {
                 final Intent intent = createServiceIntent();
                 intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
@@ -120,7 +123,7 @@ public class ServiceStartPerfTest extends BasePerfTest {
 
                 return endTimeNs - startTimeNs;
             } finally {
-                unbindFromService(alreadyBoundServiceConnection);
+                TargetPackageUtils.unbindFromService(mContext, alreadyBoundServiceConnection);
             }
         });
     }
diff --git a/tests/ActivityManagerPerfTests/tests/src/com/android/frameworks/perftests/am/util/TargetPackageUtils.java b/tests/ActivityManagerPerfTests/tests/src/com/android/frameworks/perftests/am/util/TargetPackageUtils.java
index 3db8abce90da..046dd6bb7dce 100644
--- a/tests/ActivityManagerPerfTests/tests/src/com/android/frameworks/perftests/am/util/TargetPackageUtils.java
+++ b/tests/ActivityManagerPerfTests/tests/src/com/android/frameworks/perftests/am/util/TargetPackageUtils.java
@@ -17,19 +17,33 @@
 package com.android.frameworks.perftests.am.util;
 
 import android.app.ActivityManager;
+import android.content.ComponentName;
 import android.content.Context;
 import android.content.Intent;
+import android.content.ServiceConnection;
 import android.content.pm.PackageManager;
+import android.os.Bundle;
+import android.os.Handler;
+import android.os.IBinder;
+import android.os.Looper;
+import android.os.ResultReceiver;
 import android.os.SystemClock;
 
+import org.junit.Assert;
+
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+
 public class TargetPackageUtils {
     private static final String TAG = TargetPackageUtils.class.getSimpleName();
 
     public static final String PACKAGE_NAME = "com.android.frameworks.perftests.amteststestapp";
     public static final String ACTIVITY_NAME = PACKAGE_NAME + ".TestActivity";
     public static final String SERVICE_NAME = PACKAGE_NAME + ".TestService";
+    private static final String START_SERVICE_NAME = PACKAGE_NAME + ".StartProcessService";
 
     private static final long WAIT_TIME_MS = 100L;
+    private static final long AWAIT_SERVICE_CONNECT_MS = 10000L;
 
     // Cache for test app's uid, so we only have to query it once.
     private static int sTestAppUid = -1;
@@ -37,11 +51,13 @@ public class TargetPackageUtils {
     /**
      * Kills the test package synchronously.
      */
-    public static void killTargetPackage(Context context) {
-        ActivityManager activityManager = context.getSystemService(ActivityManager.class);
+    public static void killTargetPackage(Context context, ServiceConnection serviceConnection) {
+        unbindFromService(context, serviceConnection);
+
+        final ActivityManager activityManager = context.getSystemService(ActivityManager.class);
         activityManager.forceStopPackage(PACKAGE_NAME);
         while (targetPackageIsRunning(context)) {
-            sleep();
+            SystemClock.sleep(WAIT_TIME_MS);
         }
 
         Utils.drainBroadcastQueue();
@@ -50,21 +66,24 @@ public class TargetPackageUtils {
     /**
      * Starts the test package synchronously. It does so by starting an Activity.
      */
-    public static void startTargetPackage(Context context, TimeReceiver timeReceiver) {
-        // "am start-activity -W PACKAGE_NAME/ACTIVITY_CLASS_NAME" still requires a sleep even
-        // though it should be synchronous, so just use Intent instead
+    public static ServiceConnection startTargetPackage(Context context) {
+        final CountDownLatch countDownLatch = new CountDownLatch(1);
         final Intent intent = new Intent();
-        intent.putExtras(timeReceiver.createReceiveTimeExtraBinder());
-        intent.setClassName(PACKAGE_NAME, ACTIVITY_NAME);
-        intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
-        context.startActivity(intent);
+        intent.putExtra(Intent.EXTRA_RESULT_RECEIVER, new CountDownResultReceiver(countDownLatch));
+        intent.setClassName(PACKAGE_NAME, START_SERVICE_NAME);
+        final ServiceConnection serviceConnection = bindAndWaitForConnectedService(context, intent);
 
-        while (!targetPackageIsRunning(context)) {
-            sleep();
+        try {
+            final boolean targetPackageIdleSuccess = countDownLatch.await(AWAIT_SERVICE_CONNECT_MS,
+                    TimeUnit.MILLISECONDS);
+            Assert.assertTrue("Timeout when waiting for ILooperIdleCallback.Stub.looperIdle()",
+                    targetPackageIdleSuccess);
+        } catch (InterruptedException e) {
+            throw new RuntimeException(e);
         }
-        // make sure Application has run
-        timeReceiver.getReceivedTimeNs(Constants.TYPE_TARGET_PACKAGE_START);
+
         Utils.drainBroadcastQueue();
+        return serviceConnection;
     }
 
     private static boolean targetPackageIsRunning(Context context) {
@@ -74,10 +93,6 @@ public class TargetPackageUtils {
         return !result.contains("(NONEXISTENT)");
     }
 
-    private static void sleep() {
-        SystemClock.sleep(WAIT_TIME_MS);
-    }
-
     private static int getTestAppUid(Context context) {
         if (sTestAppUid == -1) {
             final PackageManager pm = context.getPackageManager();
@@ -90,5 +105,45 @@ public class TargetPackageUtils {
         return sTestAppUid;
     }
 
+    public static ServiceConnection bindAndWaitForConnectedService(Context context, Intent intent) {
+        return bindAndWaitForConnectedService(context, intent, 0);
+    }
+
+    public static ServiceConnection bindAndWaitForConnectedService(Context context, Intent intent,
+            int bindFlags) {
+        final CountDownLatch countDownLatch = new CountDownLatch(1);
+        final ServiceConnection serviceConnection = new ServiceConnection() {
+            @Override
+            public void onServiceConnected(ComponentName name, IBinder service) {
+                countDownLatch.countDown();
+            }
+
+            @Override
+            public void onServiceDisconnected(ComponentName name) {
+            }
+        };
+
+        final boolean success = context.bindService(intent, serviceConnection,
+                Context.BIND_AUTO_CREATE | bindFlags);
+        Assert.assertTrue("Could not bind to service", success);
+
+        try {
+            final boolean connectedSuccess = countDownLatch.await(AWAIT_SERVICE_CONNECT_MS,
+                    TimeUnit.MILLISECONDS);
+            Assert.assertTrue("Timeout when waiting for ServiceConnection.onServiceConnected()",
+                    connectedSuccess);
+        } catch (InterruptedException e) {
+            throw new RuntimeException(e);
+        }
+
+        return serviceConnection;
+    }
+
+    public static void unbindFromService(Context context, ServiceConnection serviceConnection) {
+        if (serviceConnection != null) {
+            context.unbindService(serviceConnection);
+        }
+    }
+
 }
 
diff --git a/tests/ActivityManagerPerfTests/utils/src/com/android/frameworks/perftests/am/util/Constants.java b/tests/ActivityManagerPerfTests/utils/src/com/android/frameworks/perftests/am/util/Constants.java
index ffb3f84cee51..9b076c507ff8 100644
--- a/tests/ActivityManagerPerfTests/utils/src/com/android/frameworks/perftests/am/util/Constants.java
+++ b/tests/ActivityManagerPerfTests/utils/src/com/android/frameworks/perftests/am/util/Constants.java
@@ -29,4 +29,5 @@ public class Constants {
             "com.android.frameworks.perftests.ACTION_BROADCAST_REGISTERED_RECEIVE";
 
     public static final String EXTRA_RECEIVER_CALLBACK = "receiver_callback_binder";
+    public static final String EXTRA_LOOPER_IDLE_CALLBACK = "looper_idle_callback_binder";
 }
diff --git a/tests/ActivityManagerPerfTests/utils/src/com/android/frameworks/perftests/am/util/CountDownResultReceiver.java b/tests/ActivityManagerPerfTests/utils/src/com/android/frameworks/perftests/am/util/CountDownResultReceiver.java
new file mode 100644
index 000000000000..6c032c45e751
--- /dev/null
+++ b/tests/ActivityManagerPerfTests/utils/src/com/android/frameworks/perftests/am/util/CountDownResultReceiver.java
@@ -0,0 +1,36 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+
+package com.android.frameworks.perftests.am.util;
+
+import android.os.Bundle;
+import android.os.ResultReceiver;
+
+import java.util.concurrent.CountDownLatch;
+
+public class CountDownResultReceiver extends ResultReceiver {
+    private CountDownLatch mCountDownLatch;
+
+    public CountDownResultReceiver(CountDownLatch countDownLatch) {
+        super(null);
+        mCountDownLatch = countDownLatch;
+    }
+
+    @Override
+    protected void onReceiveResult(int resultCode, Bundle resultData) {
+        mCountDownLatch.countDown();
+    }
+}
diff --git a/tests/ActivityManagerPerfTests/utils/src/com/android/frameworks/perftests/am/util/Utils.java b/tests/ActivityManagerPerfTests/utils/src/com/android/frameworks/perftests/am/util/Utils.java
index 493d8cdd0803..67071d204eff 100644
--- a/tests/ActivityManagerPerfTests/utils/src/com/android/frameworks/perftests/am/util/Utils.java
+++ b/tests/ActivityManagerPerfTests/utils/src/com/android/frameworks/perftests/am/util/Utils.java
@@ -18,6 +18,7 @@ package com.android.frameworks.perftests.am.util;
 
 import android.content.Intent;
 import android.os.RemoteException;
+import android.os.ResultReceiver;
 import android.support.test.InstrumentationRegistry;
 import android.support.test.uiautomator.UiDevice;
 import android.util.Log;
@@ -56,4 +57,12 @@ public class Utils {
             Log.e(TAG, e.getMessage());
         }
     }
+
+    /**
+     * Notify the listener that the main Looper queue is idle.
+     */
+    public static void sendLooperIdle(Intent intent) {
+        ResultReceiver resultReceiver = intent.getParcelableExtra(Intent.EXTRA_RESULT_RECEIVER);
+        resultReceiver.send(0, null);
+    }
 }