TaskScheduler: Remove base/task_scheduler/utils.h/.cc

base/task_scheduler/scheduler_thread_pool_impl.cc

Index: base/task_scheduler/scheduler_thread_pool_impl.cc
diff --git a/base/task_scheduler/scheduler_thread_pool.cc b/base/task_scheduler/scheduler_thread_pool_impl.cc
similarity index 64%
rename from base/task_scheduler/scheduler_thread_pool.cc
rename to base/task_scheduler/scheduler_thread_pool_impl.cc
index 6e14638da37077aa04df244f182fba3e917a6875..e72ea6e12ceb326ab408a68a9aaf91d26efae9ea 100644
--- a/base/task_scheduler/scheduler_thread_pool.cc
+++ b/base/task_scheduler/scheduler_thread_pool_impl.cc
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "base/task_scheduler/scheduler_thread_pool.h"
+#include "base/task_scheduler/scheduler_thread_pool_impl.h"
 
 #include <utility>
 
@@ -12,7 +12,8 @@
 #include "base/logging.h"
 #include "base/memory/ptr_util.h"
 #include "base/sequenced_task_runner.h"
-#include "base/task_scheduler/utils.h"
+#include "base/task_scheduler/delayed_task_manager.h"
+#include "base/task_scheduler/task_tracker.h"
 #include "base/threading/thread_local.h"
 
 namespace base {
@@ -21,48 +22,40 @@ namespace internal {
 namespace {
 
 // SchedulerThreadPool that owns the current thread, if any.
-LazyInstance<ThreadLocalPointer<const SchedulerTaskExecutor>>::Leaky
+LazyInstance<ThreadLocalPointer<const SchedulerThreadPool>>::Leaky
     tls_current_thread_pool = LAZY_INSTANCE_INITIALIZER;
 
 // A task runner that runs tasks with the PARALLEL ExecutionMode.
 class SchedulerParallelTaskRunner : public TaskRunner {
  public:
   // Constructs a SchedulerParallelTaskRunner which can be used to post tasks so
-  // long as |executor| is alive.
-  // TODO(robliao): Find a concrete way to manage |executor|'s memory.
+  // long as |thread_pool| is alive.
+  // TODO(robliao): Find a concrete way to manage |thread_pool|'s memory.
   SchedulerParallelTaskRunner(const TaskTraits& traits,
-                              SchedulerTaskExecutor* executor,
-                              TaskTracker* task_tracker,
-                              DelayedTaskManager* delayed_task_manager)
-      : traits_(traits),
-        executor_(executor),
-        task_tracker_(task_tracker),
-        delayed_task_manager_(delayed_task_manager) {}
+                              SchedulerThreadPool* thread_pool)
+      : traits_(traits), thread_pool_(thread_pool) {}
 
   // TaskRunner:
   bool PostDelayedTask(const tracked_objects::Location& from_here,
                        const Closure& closure,
                        TimeDelta delay) override {
     // Post the task as part of a one-off single-task Sequence.
-    return PostTaskToExecutor(
+    return thread_pool_->PostTaskWithSequence(
         WrapUnique(
             new Task(from_here, closure, traits_,
                      delay.is_zero() ? TimeTicks() : TimeTicks::Now() + delay)),
-        make_scoped_refptr(new Sequence), executor_, task_tracker_,
-        delayed_task_manager_);
+        make_scoped_refptr(new Sequence));
   }
 
   bool RunsTasksOnCurrentThread() const override {
-    return tls_current_thread_pool.Get().Get() == executor_;
+    return tls_current_thread_pool.Get().Get() == thread_pool_;
   }
 
  private:
   ~SchedulerParallelTaskRunner() override = default;
 
   const TaskTraits traits_;
-  SchedulerTaskExecutor* const executor_;
-  TaskTracker* const task_tracker_;
-  DelayedTaskManager* const delayed_task_manager_;
+  SchedulerThreadPool* const thread_pool_;
 
   DISALLOW_COPY_AND_ASSIGN(SchedulerParallelTaskRunner);
 };
@@ -70,28 +63,23 @@ class SchedulerParallelTaskRunner : public TaskRunner {
 // A task runner that runs tasks with the SEQUENCED ExecutionMode.
 class SchedulerSequencedTaskRunner : public SequencedTaskRunner {
  public:
-  // Constructs a SchedulerParallelTaskRunner which can be used to post tasks so
-  // long as |executor| is alive.
-  // TODO(robliao): Find a concrete way to manage |executor|'s memory.
+  // Constructs a SchedulerSequencedTaskRunner which can be used to post tasks
+  // so long as |thread_pool| is alive.
+  // TODO(robliao): Find a concrete way to manage |thread_pool|'s memory.
   SchedulerSequencedTaskRunner(const TaskTraits& traits,
-                               SchedulerTaskExecutor* executor,
-                               TaskTracker* task_tracker,
-                               DelayedTaskManager* delayed_task_manager)
-      : traits_(traits),
-        executor_(executor),
-        task_tracker_(task_tracker),
-        delayed_task_manager_(delayed_task_manager) {}
+                               SchedulerThreadPool* thread_pool)
+      : traits_(traits), thread_pool_(thread_pool) {}
 
   // SequencedTaskRunner:
   bool PostDelayedTask(const tracked_objects::Location& from_here,
                        const Closure& closure,
                        TimeDelta delay) override {
     // Post the task as part of |sequence|.
-    return PostTaskToExecutor(
+    return thread_pool_->PostTaskWithSequence(
         WrapUnique(
             new Task(from_here, closure, traits_,
                      delay.is_zero() ? TimeTicks() : TimeTicks::Now() + delay)),
-        sequence_, executor_, task_tracker_, delayed_task_manager_);
+        sequence_);
   }
 
   bool PostNonNestableDelayedTask(const tracked_objects::Location& from_here,
@@ -102,7 +90,7 @@ class SchedulerSequencedTaskRunner : public SequencedTaskRunner {
   }
 
   bool RunsTasksOnCurrentThread() const override {
-    return tls_current_thread_pool.Get().Get() == executor_;
+    return tls_current_thread_pool.Get().Get() == thread_pool_;
   }
 
  private:
@@ -112,66 +100,78 @@ class SchedulerSequencedTaskRunner : public SequencedTaskRunner {
   const scoped_refptr<Sequence> sequence_ = new Sequence;
 
   const TaskTraits traits_;
-  SchedulerTaskExecutor* const executor_;
-  TaskTracker* const task_tracker_;
-  DelayedTaskManager* const delayed_task_manager_;
+  SchedulerThreadPool* const thread_pool_;
 
   DISALLOW_COPY_AND_ASSIGN(SchedulerSequencedTaskRunner);
 };
 
 }  // namespace
 
-class SchedulerThreadPool::SchedulerWorkerThreadDelegateImpl
+class SchedulerThreadPoolImpl::SchedulerWorkerThreadDelegateImpl
     : public SchedulerWorkerThread::Delegate {
  public:
   SchedulerWorkerThreadDelegateImpl(
-      SchedulerThreadPool* outer,
-      const EnqueueSequenceCallback& enqueue_sequence_callback);
+      SchedulerThreadPoolImpl* outer,
+      const ReEnqueueSequenceCallback& re_enqueue_sequence_callback);
   ~SchedulerWorkerThreadDelegateImpl() override;
 
   // SchedulerWorkerThread::Delegate:
   void OnMainEntry() override;
   scoped_refptr<Sequence> GetWork(
       SchedulerWorkerThread* worker_thread) override;
-  void EnqueueSequence(scoped_refptr<Sequence> sequence) override;
+  void ReEnqueueSequence(scoped_refptr<Sequence> sequence) override;
 
  private:
-  SchedulerThreadPool* outer_;
-  const EnqueueSequenceCallback enqueue_sequence_callback_;
+  SchedulerThreadPoolImpl* outer_;
+  const ReEnqueueSequenceCallback re_enqueue_sequence_callback_;
 
   DISALLOW_COPY_AND_ASSIGN(SchedulerWorkerThreadDelegateImpl);
 };
 
-SchedulerThreadPool::~SchedulerThreadPool() {
+SchedulerThreadPoolImpl::~SchedulerThreadPoolImpl() {
   // SchedulerThreadPool should never be deleted in production unless its
   // initialization failed.
   DCHECK(join_for_testing_returned_.IsSignaled() || worker_threads_.empty());
 }
 
-std::unique_ptr<SchedulerThreadPool> SchedulerThreadPool::CreateThreadPool(
+std::unique_ptr<SchedulerThreadPoolImpl>
+SchedulerThreadPoolImpl::CreateThreadPool(
     ThreadPriority thread_priority,
     size_t max_threads,
-    const EnqueueSequenceCallback& enqueue_sequence_callback,
+    const ReEnqueueSequenceCallback& re_enqueue_sequence_callback,
     TaskTracker* task_tracker,
     DelayedTaskManager* delayed_task_manager) {
-  std::unique_ptr<SchedulerThreadPool> thread_pool(new SchedulerThreadPool(
-      enqueue_sequence_callback, task_tracker, delayed_task_manager));
+  std::unique_ptr<SchedulerThreadPoolImpl> thread_pool(
+      new SchedulerThreadPoolImpl(re_enqueue_sequence_callback, task_tracker,
+                                  delayed_task_manager));
   if (thread_pool->Initialize(thread_priority, max_threads))
     return thread_pool;
   return nullptr;
 }
 
-scoped_refptr<TaskRunner> SchedulerThreadPool::CreateTaskRunnerWithTraits(
+void SchedulerThreadPoolImpl::WaitForAllWorkerThreadsIdleForTesting() {
+  AutoSchedulerLock auto_lock(idle_worker_threads_stack_lock_);
+  while (idle_worker_threads_stack_.Size() < worker_threads_.size())
+    idle_worker_threads_stack_cv_for_testing_->Wait();
+}
+
+void SchedulerThreadPoolImpl::JoinForTesting() {
+  for (const auto& worker_thread : worker_threads_)
+    worker_thread->JoinForTesting();
+
+  DCHECK(!join_for_testing_returned_.IsSignaled());
+  join_for_testing_returned_.Signal();
+}
+
+scoped_refptr<TaskRunner> SchedulerThreadPoolImpl::CreateTaskRunnerWithTraits(
     const TaskTraits& traits,
     ExecutionMode execution_mode) {
   switch (execution_mode) {
     case ExecutionMode::PARALLEL:
-      return make_scoped_refptr(new SchedulerParallelTaskRunner(
-          traits, this, task_tracker_, delayed_task_manager_));
+      return make_scoped_refptr(new SchedulerParallelTaskRunner(traits, this));
 
     case ExecutionMode::SEQUENCED:
-      return make_scoped_refptr(new SchedulerSequencedTaskRunner(
-          traits, this, task_tracker_, delayed_task_manager_));
+      return make_scoped_refptr(new SchedulerSequencedTaskRunner(traits, this));
 
     case ExecutionMode::SINGLE_THREADED:
       // TODO(fdoray): Support SINGLE_THREADED TaskRunners.
@@ -183,7 +183,7 @@ scoped_refptr<TaskRunner> SchedulerThreadPool::CreateTaskRunnerWithTraits(
   return nullptr;
 }
 
-void SchedulerThreadPool::EnqueueSequence(
+void SchedulerThreadPoolImpl::ReEnqueueSequence(
     scoped_refptr<Sequence> sequence,
     const SequenceSortKey& sequence_sort_key) {
   shared_priority_queue_.BeginTransaction()->Push(
@@ -202,51 +202,70 @@ void SchedulerThreadPool::EnqueueSequence(
     WakeUpOneThread();
 }
 
-void SchedulerThreadPool::WaitForAllWorkerThreadsIdleForTesting() {
-  AutoSchedulerLock auto_lock(idle_worker_threads_stack_lock_);
-  while (idle_worker_threads_stack_.Size() < worker_threads_.size())
-    idle_worker_threads_stack_cv_for_testing_->Wait();
-}
+bool SchedulerThreadPoolImpl::PostTaskWithSequence(
+    std::unique_ptr<Task> task,
+    scoped_refptr<Sequence> sequence) {
+  DCHECK(task);
+  DCHECK(sequence);
 
-void SchedulerThreadPool::JoinForTesting() {
-  for (const auto& worker_thread : worker_threads_)
-    worker_thread->JoinForTesting();
+  if (!task_tracker_->WillPostTask(task.get()))
+    return false;
 
-  DCHECK(!join_for_testing_returned_.IsSignaled());
-  join_for_testing_returned_.Signal();
+  if (task->delayed_run_time.is_null()) {
+    PostTaskWithSequenceNow(std::move(task), std::move(sequence));
+  } else {
+    delayed_task_manager_->AddDelayedTask(std::move(task), std::move(sequence),
+                                          this);
+  }
+
+  return true;
 }
 
-void SchedulerThreadPool::PostTaskWithSequence(
+void SchedulerThreadPoolImpl::PostTaskWithSequenceNow(
     std::unique_ptr<Task> task,
     scoped_refptr<Sequence> sequence) {
   DCHECK(task);
   DCHECK(sequence);
 
-  const bool sequence_was_empty = AddTaskToSequenceAndPriorityQueue(
-      std::move(task), std::move(sequence), &shared_priority_queue_);
-
-  // No thread has already been woken up to run Tasks from |sequence| if it was
-  // empty before |task| was inserted into it.
-  if (sequence_was_empty)
+  // Confirm that |task| is ready to run (its delayed run time is either null or
+  // in the past).
+  DCHECK_LE(task->delayed_run_time, delayed_task_manager_->Now());
+
+  const bool sequence_was_empty = sequence->PushTask(std::move(task));
+  if (sequence_was_empty) {
+    // Insert |sequence| in |shared_priority_queue_| if it was empty before
+    // |task| was inserted into it. Otherwise, one of these must be true:
+    // - |sequence| is already in a PriorityQueue (not necessarily
+    //   |shared_priority_queue_|), or,
+    // - A worker thread is running a Task from |sequence|. It will insert
+    //   |sequence| in a PriorityQueue once it's done running the Task.
+    const auto sequence_sort_key = sequence->GetSortKey();
+    shared_priority_queue_.BeginTransaction()->Push(
+        WrapUnique(new PriorityQueue::SequenceAndSortKey(std::move(sequence),
+                                                         sequence_sort_key)));
+
+    // Wake up a worker thread to process |sequence|.
     WakeUpOneThread();
+  }
 }
 
-SchedulerThreadPool::SchedulerWorkerThreadDelegateImpl::
+SchedulerThreadPoolImpl::SchedulerWorkerThreadDelegateImpl::
     SchedulerWorkerThreadDelegateImpl(
-        SchedulerThreadPool* outer,
-        const EnqueueSequenceCallback& enqueue_sequence_callback)
-    : outer_(outer), enqueue_sequence_callback_(enqueue_sequence_callback) {}
+        SchedulerThreadPoolImpl* outer,
+        const ReEnqueueSequenceCallback& re_enqueue_sequence_callback)
+    : outer_(outer),
+      re_enqueue_sequence_callback_(re_enqueue_sequence_callback) {}
 
-SchedulerThreadPool::SchedulerWorkerThreadDelegateImpl::
+SchedulerThreadPoolImpl::SchedulerWorkerThreadDelegateImpl::
     ~SchedulerWorkerThreadDelegateImpl() = default;
 
-void SchedulerThreadPool::SchedulerWorkerThreadDelegateImpl::OnMainEntry() {
+void SchedulerThreadPoolImpl::SchedulerWorkerThreadDelegateImpl::OnMainEntry() {
   DCHECK(!tls_current_thread_pool.Get().Get());
   tls_current_thread_pool.Get().Set(outer_);
 }
 
 scoped_refptr<Sequence>
-SchedulerThreadPool::SchedulerWorkerThreadDelegateImpl::GetWork(
+SchedulerThreadPoolImpl::SchedulerWorkerThreadDelegateImpl::GetWork(
     SchedulerWorkerThread* worker_thread) {
   std::unique_ptr<PriorityQueue::Transaction> transaction(
       outer_->shared_priority_queue_.BeginTransaction());
@@ -274,13 +293,13 @@ SchedulerThreadPool::SchedulerWorkerThreadDelegateImpl::GetWork(
   return sequence;
 }
 
-void SchedulerThreadPool::SchedulerWorkerThreadDelegateImpl::EnqueueSequence(
-    scoped_refptr<Sequence> sequence) {
-  enqueue_sequence_callback_.Run(std::move(sequence));
+void SchedulerThreadPoolImpl::SchedulerWorkerThreadDelegateImpl::
+    ReEnqueueSequence(scoped_refptr<Sequence> sequence) {
+  re_enqueue_sequence_callback_.Run(std::move(sequence));
 }
 
-SchedulerThreadPool::SchedulerThreadPool(
-    const EnqueueSequenceCallback& enqueue_sequence_callback,
+SchedulerThreadPoolImpl::SchedulerThreadPoolImpl(
+    const ReEnqueueSequenceCallback& re_enqueue_sequence_callback,
     TaskTracker* task_tracker,
     DelayedTaskManager* delayed_task_manager)
     : idle_worker_threads_stack_lock_(shared_priority_queue_.container_lock()),
@@ -289,15 +308,15 @@ SchedulerThreadPool::SchedulerThreadPool(
       join_for_testing_returned_(true, false),
       worker_thread_delegate_(
           new SchedulerWorkerThreadDelegateImpl(this,
-                                                enqueue_sequence_callback)),
+                                                re_enqueue_sequence_callback)),
       task_tracker_(task_tracker),
       delayed_task_manager_(delayed_task_manager) {
   DCHECK(task_tracker_);
   DCHECK(delayed_task_manager_);
 }
 
-bool SchedulerThreadPool::Initialize(ThreadPriority thread_priority,
-                                     size_t max_threads) {
+bool SchedulerThreadPoolImpl::Initialize(ThreadPriority thread_priority,
+                                         size_t max_threads) {
   AutoSchedulerLock auto_lock(idle_worker_threads_stack_lock_);
 
   DCHECK(worker_threads_.empty());
@@ -315,7 +334,7 @@ bool SchedulerThreadPool::Initialize(ThreadPriority thread_priority,
   return !worker_threads_.empty();
 }
 
-void SchedulerThreadPool::WakeUpOneThread() {
+void SchedulerThreadPoolImpl::WakeUpOneThread() {
   SchedulerWorkerThread* worker_thread;
   {
     AutoSchedulerLock auto_lock(idle_worker_threads_stack_lock_);
@@ -325,7 +344,7 @@ void SchedulerThreadPool::WakeUpOneThread() {
     worker_thread->WakeUp();
 }
 
-void SchedulerThreadPool::AddToIdleWorkerThreadsStack(
+void SchedulerThreadPoolImpl::AddToIdleWorkerThreadsStack(
     SchedulerWorkerThread* worker_thread) {
   AutoSchedulerLock auto_lock(idle_worker_threads_stack_lock_);
   idle_worker_threads_stack_.Push(worker_thread);