Allow setting a persistent VR thread.

Bug: 36215076
Test: adb shell am instrument -w -e class \
android.os.SetPersistentVrThreadTest \
com.android.frameworks.coretests/\
android.support.test.runner.AndroidJUnitRunner
cts-tradefed run cts -m CtsVrTestCases -t android.vr.cts.VrSetFIFOThreadTest
Change-Id: If2f3a5f1c8593c74ac35964f68dcbe75b4da472e
diff --git a/core/tests/coretests/src/android/os/SetPersistentVrThreadTest.java b/core/tests/coretests/src/android/os/SetPersistentVrThreadTest.java
new file mode 100644
index 0000000..920988b
--- /dev/null
+++ b/core/tests/coretests/src/android/os/SetPersistentVrThreadTest.java
@@ -0,0 +1,162 @@
+/*
+ * Copyright (C) 2017 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 android.os;
+
+import android.app.ActivityManager;
+import android.app.VrManager;
+import android.content.ComponentName;
+import android.content.Context;
+import android.content.pm.PackageManager;
+import android.os.Process;
+import android.provider.Settings;
+import android.test.ActivityInstrumentationTestCase2;
+import android.test.suitebuilder.annotation.SmallTest;
+import android.util.Log;
+
+/**
+ * Tests ActivityManager#setPersistentVrThread and ActivityManager#setVrThread's
+ * interaction with persistent VR mode.
+ */
+public class SetPersistentVrThreadTest extends ActivityInstrumentationTestCase2<TestVrActivity> {
+    private TestVrActivity mActivity;
+    private ActivityManager mActivityManager;
+    private VrManager mVrManager;
+    private Context mContext;
+    private String mOldVrListener;
+    private ComponentName mRequestedComponent;
+    private static final int SCHED_OTHER = 0;
+    private static final int SCHED_FIFO = 1;
+    private static final int SCHED_RESET_ON_FORK = 0x40000000;
+    public static final String ENABLED_VR_LISTENERS = "enabled_vr_listeners";
+    private static final String TAG = "VrSetPersistentFIFOThreadTest";
+
+    public SetPersistentVrThreadTest() {
+        super(TestVrActivity.class);
+    }
+
+    @Override
+    protected void setUp() throws Exception {
+        super.setUp();
+        mContext = getInstrumentation().getTargetContext();
+        mActivityManager = (ActivityManager) mContext.getSystemService(Context.ACTIVITY_SERVICE);
+        mVrManager = (VrManager) mContext.getSystemService(Context.VR_SERVICE);
+
+        mRequestedComponent = new ComponentName(mContext,
+                TestVrActivity.TestVrListenerService.class);
+        mOldVrListener = Settings.Secure.getString(mContext.getContentResolver(),
+                ENABLED_VR_LISTENERS);
+        Settings.Secure.putString(mContext.getContentResolver(), ENABLED_VR_LISTENERS,
+                mRequestedComponent.flattenToString());
+        mActivity = getActivity();
+    }
+
+    @Override
+    protected void tearDown() throws Exception {
+        try {
+            setPersistentVrModeEnabled(false);
+        } catch (Throwable e) {
+            // pass
+        }
+        Settings.Secure.putString(mContext.getContentResolver(), ENABLED_VR_LISTENERS,
+                mOldVrListener);
+        super.tearDown();
+    }
+
+    private void setPersistentVrModeEnabled(boolean enable) throws Throwable {
+        mVrManager.setPersistentVrModeEnabled(enable);
+        // Allow the system time to send out callbacks for persistent VR mode.
+        Thread.sleep(200);
+    }
+
+    @SmallTest
+    public void testSetPersistentVrThreadAPISuccess() throws Throwable {
+        if (!mActivity.getPackageManager().hasSystemFeature(
+                PackageManager.FEATURE_VR_MODE_HIGH_PERFORMANCE)) {
+            return;
+        }
+
+        int vr_thread = 0, policy = 0;
+        vr_thread = Process.myTid();
+
+        setPersistentVrModeEnabled(true);
+        mActivityManager.setPersistentVrThread(vr_thread);
+        policy = (int) Process.getThreadScheduler(vr_thread);
+        assertEquals((SCHED_FIFO | SCHED_RESET_ON_FORK), policy);
+
+        // Check that the thread loses priority when persistent mode is disabled.
+        setPersistentVrModeEnabled(false);
+        policy = (int) Process.getThreadScheduler(vr_thread);
+        assertEquals(SCHED_OTHER, policy);
+
+        // Check that disabling VR mode when in persistent mode does not affect the persistent
+        // thread.
+        mActivity.setVrModeEnabled(true, mRequestedComponent);
+        Thread.sleep(200);
+        setPersistentVrModeEnabled(true);
+        Thread.sleep(200);
+        mActivityManager.setPersistentVrThread(vr_thread);
+        policy = (int) Process.getThreadScheduler(vr_thread);
+        assertEquals((SCHED_FIFO | SCHED_RESET_ON_FORK), policy);
+        mActivity.setVrModeEnabled(false, mRequestedComponent);
+        Thread.sleep(200);
+        assertEquals((SCHED_FIFO | SCHED_RESET_ON_FORK), policy);
+        setPersistentVrModeEnabled(false);
+        policy = (int) Process.getThreadScheduler(vr_thread);
+        assertEquals(SCHED_OTHER, policy);
+    }
+
+    @SmallTest
+    public void testSetPersistentVrThreadAPIFailure() throws Throwable {
+        if (!mActivity.getPackageManager().hasSystemFeature(
+                PackageManager.FEATURE_VR_MODE_HIGH_PERFORMANCE)) {
+            return;
+        }
+        int vr_thread = 0, policy = 0;
+        vr_thread = Process.myTid();
+        mActivityManager.setPersistentVrThread(vr_thread);
+        policy = (int) Process.getThreadScheduler(vr_thread);
+        assertEquals(SCHED_OTHER, policy);
+    }
+
+    @SmallTest
+    public void testSetVrThreadAPIFailsInPersistentMode() throws Throwable {
+        if (!mActivity.getPackageManager().hasSystemFeature(
+                PackageManager.FEATURE_VR_MODE_HIGH_PERFORMANCE)) {
+            return;
+        }
+        int vr_thread = 0, policy = 0;
+        mActivity.setVrModeEnabled(true, mRequestedComponent);
+        vr_thread = Process.myTid();
+
+        setPersistentVrModeEnabled(true);
+        mActivityManager.setVrThread(vr_thread);
+        policy = (int) Process.getThreadScheduler(vr_thread);
+        assertEquals(SCHED_OTHER, policy);
+        setPersistentVrModeEnabled(false);
+
+        // When not in persistent mode the API works again.
+        mActivity.setVrModeEnabled(true, mRequestedComponent);
+        mActivityManager.setVrThread(vr_thread);
+        policy = (int) Process.getThreadScheduler(vr_thread);
+        assertEquals((SCHED_FIFO | SCHED_RESET_ON_FORK), policy);
+
+        // The thread loses priority when persistent mode is disabled.
+        setPersistentVrModeEnabled(true);
+        policy = (int) Process.getThreadScheduler(vr_thread);
+        assertEquals(SCHED_OTHER, policy);
+        setPersistentVrModeEnabled(false);
+    }
+}