[content]: Ensure TaskQueueManager AFTER_WAKEUP autopump policy wakes only on newer tasks.

content/renderer/scheduler/task_queue_manager_unittest.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/renderer/scheduler/task_queue_manager.h"
 
 #include "base/test/test_simple_task_runner.h"
 #include "base/threading/thread.h"
 #include "cc/test/test_now_source.h"
 #include "content/renderer/scheduler/task_queue_selector.h"
@@ skipping 40 matching lines @@
   DISALLOW_COPY_AND_ASSIGN(SelectorForTest);
 };
 
 class TaskQueueManagerTest : public testing::Test {
  protected:
   void Initialize(size_t num_queues) {
     test_task_runner_ = make_scoped_refptr(new base::TestSimpleTaskRunner());
     selector_ = make_scoped_ptr(new SelectorForTest);
     manager_ = make_scoped_ptr(
         new TaskQueueManager(num_queues, test_task_runner_, selector_.get()));
+    EXPECT_EQ(num_queues, selector_->work_queues().size());
   }
 
   void InitializeWithRealMessageLoop(size_t num_queues) {
     message_loop_.reset(new base::MessageLoop());
     selector_ = make_scoped_ptr(new SelectorForTest);
     manager_ = make_scoped_ptr(new TaskQueueManager(
         num_queues, message_loop_->task_runner(), selector_.get()));
+    EXPECT_EQ(num_queues, selector_->work_queues().size());
   }
 
   scoped_refptr<base::TestSimpleTaskRunner> test_task_runner_;
   scoped_ptr<SelectorForTest> selector_;
   scoped_ptr<TaskQueueManager> manager_;
   scoped_ptr<base::MessageLoop> message_loop_;
 };
 
 void PostFromNestedRunloop(base::MessageLoop* message_loop,
                            base::SingleThreadTaskRunner* runner,
                            std::vector<std::pair<base::Closure, bool>>* tasks) {
   base::MessageLoop::ScopedNestableTaskAllower allow(message_loop);
   for (std::pair<base::Closure, bool>& pair : *tasks) {
     if (pair.second) {
       runner->PostTask(FROM_HERE, pair.first);
     } else {
       runner->PostNonNestableTask(FROM_HERE, pair.first);
     }
   }
   message_loop->RunUntilIdle();
 }
 
 void TestTask(int value, std::vector<int>* out_result) {
   out_result->push_back(value);
 }
 
 TEST_F(TaskQueueManagerTest, SingleQueuePosting) {
   Initialize(1u);
-  EXPECT_EQ(1u, selector_->work_queues().size());
 
   std::vector<int> run_order;
   scoped_refptr<base::SingleThreadTaskRunner> runner =
       manager_->TaskRunnerForQueue(0);
 
   runner->PostTask(FROM_HERE, base::Bind(&TestTask, 1, &run_order));
   runner->PostTask(FROM_HERE, base::Bind(&TestTask, 2, &run_order));
   runner->PostTask(FROM_HERE, base::Bind(&TestTask, 3, &run_order));
 
   selector_->AppendQueueToService(0);
   selector_->AppendQueueToService(0);
   selector_->AppendQueueToService(0);
 
   test_task_runner_->RunUntilIdle();
   EXPECT_THAT(run_order, ElementsAre(1, 2, 3));
 }
 
 TEST_F(TaskQueueManagerTest, MultiQueuePosting) {
   Initialize(3u);
-  EXPECT_EQ(3u, selector_->work_queues().size());
 
   std::vector<int> run_order;
   scoped_refptr<base::SingleThreadTaskRunner> runners[3] = {
       manager_->TaskRunnerForQueue(0),
       manager_->TaskRunnerForQueue(1),
       manager_->TaskRunnerForQueue(2)};
 
   selector_->AppendQueueToService(0);
   selector_->AppendQueueToService(1);
   selector_->AppendQueueToService(2);
   selector_->AppendQueueToService(0);
   selector_->AppendQueueToService(1);
   selector_->AppendQueueToService(2);
 
   runners[0]->PostTask(FROM_HERE, base::Bind(&TestTask, 1, &run_order));
   runners[0]->PostTask(FROM_HERE, base::Bind(&TestTask, 2, &run_order));
   runners[1]->PostTask(FROM_HERE, base::Bind(&TestTask, 3, &run_order));
   runners[1]->PostTask(FROM_HERE, base::Bind(&TestTask, 4, &run_order));
   runners[2]->PostTask(FROM_HERE, base::Bind(&TestTask, 5, &run_order));
   runners[2]->PostTask(FROM_HERE, base::Bind(&TestTask, 6, &run_order));
 
   test_task_runner_->RunUntilIdle();
   EXPECT_THAT(run_order, ElementsAre(1, 3, 5, 2, 4, 6));
 }
 
 TEST_F(TaskQueueManagerTest, NonNestableTaskPosting) {
   InitializeWithRealMessageLoop(1u);
-  EXPECT_EQ(1u, selector_->work_queues().size());
 
   std::vector<int> run_order;
   scoped_refptr<base::SingleThreadTaskRunner> runner =
       manager_->TaskRunnerForQueue(0);
 
   selector_->AppendQueueToService(0);
 
   runner->PostNonNestableTask(FROM_HERE, base::Bind(&TestTask, 1, &run_order));
 
   message_loop_->RunUntilIdle();
   EXPECT_THAT(run_order, ElementsAre(1));
 }
 
 TEST_F(TaskQueueManagerTest, NonNestableTaskExecutesInExpectedOrder) {
   InitializeWithRealMessageLoop(1u);
-  EXPECT_EQ(1u, selector_->work_queues().size());
 
   std::vector<int> run_order;
   scoped_refptr<base::SingleThreadTaskRunner> runner =
       manager_->TaskRunnerForQueue(0);
 
   selector_->AppendQueueToService(0);
   selector_->AppendQueueToService(0);
   selector_->AppendQueueToService(0);
   selector_->AppendQueueToService(0);
   selector_->AppendQueueToService(0);
 
   runner->PostTask(FROM_HERE, base::Bind(&TestTask, 1, &run_order));
   runner->PostTask(FROM_HERE, base::Bind(&TestTask, 2, &run_order));
   runner->PostTask(FROM_HERE, base::Bind(&TestTask, 3, &run_order));
   runner->PostTask(FROM_HERE, base::Bind(&TestTask, 4, &run_order));
   runner->PostNonNestableTask(FROM_HERE, base::Bind(&TestTask, 5, &run_order));
 
   message_loop_->RunUntilIdle();
   EXPECT_THAT(run_order, ElementsAre(1, 2, 3, 4, 5));
 }
 
 TEST_F(TaskQueueManagerTest, NonNestableTaskDoesntExecuteInNestedLoop) {
   InitializeWithRealMessageLoop(1u);
-  EXPECT_EQ(1u, selector_->work_queues().size());
 
   std::vector<int> run_order;
   scoped_refptr<base::SingleThreadTaskRunner> runner =
       manager_->TaskRunnerForQueue(0);
 
   selector_->AppendQueueToService(0);
   selector_->AppendQueueToService(0);
   selector_->AppendQueueToService(0);
   selector_->AppendQueueToService(0);
   selector_->AppendQueueToService(0);
@@ skipping 200 matching lines @@
                        std::vector<int>* out_result) {
   out_result->push_back(countdown);
   if (--countdown) {
     runner->PostTask(FROM_HERE,
                      Bind(&ReentrantTestTask, runner, countdown, out_result));
   }
 }
 
 TEST_F(TaskQueueManagerTest, ReentrantPosting) {
   Initialize(1u);
-  EXPECT_EQ(1u, selector_->work_queues().size());
 
   std::vector<int> run_order;
   scoped_refptr<base::SingleThreadTaskRunner> runner =
       manager_->TaskRunnerForQueue(0);
 
   runner->PostTask(FROM_HERE, Bind(&ReentrantTestTask, runner, 3, &run_order));
 
   selector_->AppendQueueToService(0);
   selector_->AppendQueueToService(0);
   selector_->AppendQueueToService(0);
@@ skipping 34 matching lines @@
   thread.Start();
   thread.message_loop()->PostTask(
       FROM_HERE, base::Bind(&PostTaskToRunner, runner, &run_order));
   thread.Stop();
 
   selector_->AppendQueueToService(0);
   message_loop_->RunUntilIdle();
   EXPECT_THAT(run_order, ElementsAre(1));
 }
 
-void RePostingTestTask(scoped_refptr<base::SingleThreadTaskRunner> runner) {
+void RePostingTestTask(scoped_refptr<base::SingleThreadTaskRunner> runner,
+                       int* run_count) {
+  (*run_count)++;
   runner->PostTask(
-      FROM_HERE, Bind(&RePostingTestTask, base::Unretained(runner.get())));
+      FROM_HERE,
+      Bind(&RePostingTestTask, base::Unretained(runner.get()), run_count));
 }
 
 TEST_F(TaskQueueManagerTest, DoWorkCantPostItselfMultipleTimes) {
   Initialize(1u);
-
   scoped_refptr<base::SingleThreadTaskRunner> runner =
       manager_->TaskRunnerForQueue(0);
 
-  runner->PostTask(FROM_HERE, base::Bind(&RePostingTestTask, runner));
+  int run_count = 0;
+  runner->PostTask(FROM_HERE,
+                   base::Bind(&RePostingTestTask, runner, &run_count));
 
   selector_->AppendQueueToService(0);
   selector_->AppendQueueToService(0);
   selector_->AppendQueueToService(0);
 
   test_task_runner_->RunPendingTasks();
   // NOTE without the executing_task_ check in MaybePostDoWorkOnMainRunner there
   // will be two tasks here.
   EXPECT_EQ(1u, test_task_runner_->GetPendingTasks().size());
+  EXPECT_EQ(1, run_count);
 }
 
 TEST_F(TaskQueueManagerTest, PostFromNestedRunloop) {
   InitializeWithRealMessageLoop(1u);
 
   selector_->AppendQueueToService(0);
   selector_->AppendQueueToService(0);
   selector_->AppendQueueToService(0);
   selector_->AppendQueueToService(0);
 
@@ skipping 85 matching lines @@
   // the work batch is interrupted by the pending delayed task.
   EXPECT_EQ(test_task_runner_->GetPendingTasks().size(), 2u);
   test_task_runner_->RunPendingTasks();
   EXPECT_THAT(run_order, ElementsAre(2));
 
   // Running all remaining tasks should execute both pending tasks.
   test_task_runner_->RunUntilIdle();
   EXPECT_THAT(run_order, ElementsAre(2, 3, 1));
 }
 
-TEST_F(TaskQueueManagerTest, AutoPumpOnWakeup) {
+TEST_F(TaskQueueManagerTest, AutoPumpAfterWakeup) {
   Initialize(2u);
-  EXPECT_EQ(2u, selector_->work_queues().size());
   manager_->SetPumpPolicy(0, TaskQueueManager::PumpPolicy::AFTER_WAKEUP);
 
   std::vector<int> run_order;
   scoped_refptr<base::SingleThreadTaskRunner> runners[2] = {
       manager_->TaskRunnerForQueue(0), manager_->TaskRunnerForQueue(1)};
 
   selector_->AppendQueueToService(1);
   selector_->AppendQueueToService(0);
   selector_->AppendQueueToService(0);
 
   runners[0]->PostTask(FROM_HERE, base::Bind(&TestTask, 1, &run_order));
   test_task_runner_->RunUntilIdle();
   EXPECT_TRUE(run_order.empty());  // Shouldn't run - no other task to wake TQM.
 
   runners[0]->PostTask(FROM_HERE, base::Bind(&TestTask, 2, &run_order));
   test_task_runner_->RunUntilIdle();
   EXPECT_TRUE(run_order.empty());  // Still shouldn't wake TQM.
 
   runners[1]->PostTask(FROM_HERE, base::Bind(&TestTask, 3, &run_order));
   test_task_runner_->RunUntilIdle();
   // Executing a task on an auto pumped queue should wake the TQM.
   EXPECT_THAT(run_order, ElementsAre(3, 1, 2));
 }
 
-TEST_F(TaskQueueManagerTest, AutoPumpOnWakeupWhenAlreadyAwake) {
+TEST_F(TaskQueueManagerTest, AutoPumpAfterWakeupWhenAlreadyAwake) {
   Initialize(2u);
-  EXPECT_EQ(2u, selector_->work_queues().size());
   manager_->SetPumpPolicy(0, TaskQueueManager::PumpPolicy::AFTER_WAKEUP);
 
   std::vector<int> run_order;
   scoped_refptr<base::SingleThreadTaskRunner> runners[2] = {
       manager_->TaskRunnerForQueue(0), manager_->TaskRunnerForQueue(1)};
 
   selector_->AppendQueueToService(1);
   selector_->AppendQueueToService(0);
 
-  runners[1]->PostTask(FROM_HERE, base::Bind(&TestTask, 1, &run_order));
-  runners[0]->PostTask(FROM_HERE, base::Bind(&TestTask, 2, &run_order));
+  runners[0]->PostTask(FROM_HERE, base::Bind(&TestTask, 1, &run_order));
+  runners[1]->PostTask(FROM_HERE, base::Bind(&TestTask, 2, &run_order));
   test_task_runner_->RunUntilIdle();
-  EXPECT_THAT(run_order, ElementsAre(1, 2));  // TQM was already awake.
+  EXPECT_THAT(run_order, ElementsAre(2, 1));  // TQM was already awake.
 }
 
-TEST_F(TaskQueueManagerTest, AutoPumpOnWakeupTriggeredByManuallyPumpedQueue) {
+TEST_F(TaskQueueManagerTest,
+       AutoPumpAfterWakeupTriggeredByManuallyPumpedQueue) {
   Initialize(2u);
-  EXPECT_EQ(2u, selector_->work_queues().size());
   manager_->SetPumpPolicy(0, TaskQueueManager::PumpPolicy::AFTER_WAKEUP);
   manager_->SetPumpPolicy(1, TaskQueueManager::PumpPolicy::MANUAL);
 
   std::vector<int> run_order;
   scoped_refptr<base::SingleThreadTaskRunner> runners[2] = {
       manager_->TaskRunnerForQueue(0), manager_->TaskRunnerForQueue(1)};
 
   selector_->AppendQueueToService(1);
   selector_->AppendQueueToService(0);
 
   runners[0]->PostTask(FROM_HERE, base::Bind(&TestTask, 1, &run_order));
   test_task_runner_->RunUntilIdle();
   EXPECT_TRUE(run_order.empty());  // Shouldn't run - no other task to wake TQM.
 
   runners[1]->PostTask(FROM_HERE, base::Bind(&TestTask, 2, &run_order));
   test_task_runner_->RunUntilIdle();
   // This still shouldn't wake TQM as manual queue was not pumped.
   EXPECT_TRUE(run_order.empty());
 
   manager_->PumpQueue(1);
   test_task_runner_->RunUntilIdle();
   // Executing a task on an auto pumped queue should wake the TQM.
   EXPECT_THAT(run_order, ElementsAre(2, 1));
 }
 
+void TestPostingTask(scoped_refptr<base::SingleThreadTaskRunner> task_runner,
+                     base::Closure task) {
+  task_runner->PostTask(FROM_HERE, task);
+}
+
+TEST_F(TaskQueueManagerTest, AutoPumpAfterWakeupFromTask) {
+  Initialize(2u);
+  manager_->SetPumpPolicy(0, TaskQueueManager::PumpPolicy::AFTER_WAKEUP);
+
+  std::vector<int> run_order;
+  scoped_refptr<base::SingleThreadTaskRunner> runners[2] = {
+      manager_->TaskRunnerForQueue(0), manager_->TaskRunnerForQueue(1)};
+
+  selector_->AppendQueueToService(1);
+  selector_->AppendQueueToService(1);
+  selector_->AppendQueueToService(0);
+
+  // Check that a task which posts a task to an auto pump after wakeup queue
+  // doesn't cause the queue to wake up.
+  base::Closure after_wakeup_task = base::Bind(&TestTask, 1, &run_order);
+  runners[1]->PostTask(
+      FROM_HERE,
+      base::Bind(&TestPostingTask, runners[0], after_wakeup_task));
+  test_task_runner_->RunUntilIdle();
+  EXPECT_TRUE(run_order.empty());
+
+  // Wake up the queue.
+  runners[1]->PostTask(FROM_HERE, base::Bind(&TestTask, 2, &run_order));
+  test_task_runner_->RunUntilIdle();
+  EXPECT_THAT(run_order, ElementsAre(2, 1));
+}
+
+TEST_F(TaskQueueManagerTest, AutoPumpAfterWakeupFromMultipleTasks) {
+  Initialize(2u);
+  manager_->SetPumpPolicy(0, TaskQueueManager::PumpPolicy::AFTER_WAKEUP);
+
+  std::vector<int> run_order;
+  scoped_refptr<base::SingleThreadTaskRunner> runners[2] = {
+      manager_->TaskRunnerForQueue(0), manager_->TaskRunnerForQueue(1)};
+
+  selector_->AppendQueueToService(1);
+  selector_->AppendQueueToService(1);
+  selector_->AppendQueueToService(1);
+  selector_->AppendQueueToService(0);
+  selector_->AppendQueueToService(0);
+
+  // Check that a task which posts a task to an auto pump after wakeup queue
+  // doesn't cause the queue to wake up.
+  base::Closure after_wakeup_task_1 = base::Bind(&TestTask, 1, &run_order);
+  base::Closure after_wakeup_task_2 = base::Bind(&TestTask, 2, &run_order);
+  runners[1]->PostTask(
+      FROM_HERE,
+      base::Bind(&TestPostingTask, runners[0], after_wakeup_task_1));
+  runners[1]->PostTask(
+      FROM_HERE,
+      base::Bind(&TestPostingTask, runners[0], after_wakeup_task_2));
+  test_task_runner_->RunUntilIdle();
+  EXPECT_TRUE(run_order.empty());
+
+  // Wake up the queue.
+  runners[1]->PostTask(FROM_HERE, base::Bind(&TestTask, 3, &run_order));
+  test_task_runner_->RunUntilIdle();
+  EXPECT_THAT(run_order, ElementsAre(3, 1, 2));
+}
+
+void NullTestTask() {
+}
+
+TEST_F(TaskQueueManagerTest, AutoPumpAfterWakeupBecomesQuiescent) {
+  Initialize(2u);
+  manager_->SetPumpPolicy(0, TaskQueueManager::PumpPolicy::AFTER_WAKEUP);
+
+  int run_count = 0;
+  scoped_refptr<base::SingleThreadTaskRunner> runners[2] = {
+      manager_->TaskRunnerForQueue(0), manager_->TaskRunnerForQueue(1)};
+
+  selector_->AppendQueueToService(1);
+  selector_->AppendQueueToService(0);
+  selector_->AppendQueueToService(0);
+  // Append extra service queue '0' entries to the selector otherwise test will
+  // finish even if the RePostingTestTask woke each other up.
+  selector_->AppendQueueToService(0);
+  selector_->AppendQueueToService(0);
+
+  // Check that if multiple tasks reposts themselves onto a pump-after-wakeup
+  // queue they don't wake each other and will eventually stop when no other
+  // tasks execute.
+  runners[0]->PostTask(FROM_HERE,
+                       base::Bind(&RePostingTestTask, runners[0], &run_count));
+  runners[0]->PostTask(FROM_HERE,
+                       base::Bind(&RePostingTestTask, runners[0], &run_count));
+  runners[1]->PostTask(FROM_HERE, base::Bind(&NullTestTask));
+  test_task_runner_->RunUntilIdle();
+  // The reposting tasks posted to the after wakeup queue shouldn't have woken
+  // each other up.
+  EXPECT_EQ(2, run_count);
+}
+
 class MockTaskObserver : public base::MessageLoop::TaskObserver {
  public:
   MOCK_METHOD1(DidProcessTask, void(const base::PendingTask& task));
   MOCK_METHOD1(WillProcessTask, void(const base::PendingTask& task));
 };
 
 TEST_F(TaskQueueManagerTest, TaskObserverAdding) {
   InitializeWithRealMessageLoop(1u);
   MockTaskObserver observer;
 
@@ skipping 56 matching lines @@
   selector_->AppendQueueToService(0);
 
   EXPECT_CALL(observer, WillProcessTask(_)).Times(1);
   EXPECT_CALL(observer, DidProcessTask(_)).Times(0);
   message_loop_->RunUntilIdle();
 }
 
 }  // namespace
 }  // namespace content