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diff --git a/runtime/thread_pool.h b/runtime/thread_pool.h
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+++ b/runtime/thread_pool.h
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+/*
+ * Copyright (C) 2012 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.
+ */
+
+#ifndef ART_SRC_THREAD_POOL_H_
+#define ART_SRC_THREAD_POOL_H_
+
+#include <deque>
+#include <vector>
+
+#include "barrier.h"
+#include "base/mutex.h"
+#include "closure.h"
+#include "locks.h"
+
+namespace art {
+
+class ThreadPool;
+
+class Task : public Closure {
+public:
+  // Called when references reaches 0.
+  virtual void Finalize() { }
+};
+
+class ThreadPoolWorker {
+ public:
+  static const size_t kDefaultStackSize = 1 * MB;
+
+  size_t GetStackSize() const {
+    return stack_size_;
+  }
+
+  virtual ~ThreadPoolWorker();
+
+ protected:
+  ThreadPoolWorker(ThreadPool* thread_pool, const std::string& name, size_t stack_size);
+  static void* Callback(void* arg) LOCKS_EXCLUDED(Locks::mutator_lock_);
+  virtual void Run();
+
+  ThreadPool* const thread_pool_;
+  const std::string name_;
+  const size_t stack_size_;
+  pthread_t pthread_;
+
+  friend class ThreadPool;
+  DISALLOW_COPY_AND_ASSIGN(ThreadPoolWorker);
+};
+
+class ThreadPool {
+ public:
+  // Returns the number of threads in the thread pool.
+  size_t GetThreadCount() const {
+    return threads_.size();
+  }
+
+  // Broadcast to the workers and tell them to empty out the work queue.
+  void StartWorkers(Thread* self);
+
+  // Do not allow workers to grab any new tasks.
+  void StopWorkers(Thread* self);
+
+  // Add a new task, the first available started worker will process it. Does not delete the task
+  // after running it, it is the caller's responsibility.
+  void AddTask(Thread* self, Task* task);
+
+  ThreadPool(size_t num_threads);
+  virtual ~ThreadPool();
+
+  // Wait for all tasks currently on queue to get completed.
+  void Wait(Thread* self, bool do_work, bool may_hold_locks);
+
+  size_t GetTaskCount(Thread* self);
+
+  // Returns the total amount of workers waited for tasks.
+  uint64_t GetWaitTime() const {
+    return total_wait_time_;
+  }
+
+ protected:
+  // Get a task to run, blocks if there are no tasks left
+  virtual Task* GetTask(Thread* self);
+
+  // Try to get a task, returning NULL if there is none available.
+  Task* TryGetTask(Thread* self);
+  Task* TryGetTaskLocked(Thread* self) EXCLUSIVE_LOCKS_REQUIRED(task_queue_lock_);
+
+  // Are we shutting down?
+  bool IsShuttingDown() const EXCLUSIVE_LOCKS_REQUIRED(task_queue_lock_) {
+    return shutting_down_;
+  }
+
+  Mutex task_queue_lock_;
+  ConditionVariable task_queue_condition_ GUARDED_BY(task_queue_lock_);
+  ConditionVariable completion_condition_ GUARDED_BY(task_queue_lock_);
+  volatile bool started_ GUARDED_BY(task_queue_lock_);
+  volatile bool shutting_down_ GUARDED_BY(task_queue_lock_);
+  // How many worker threads are waiting on the condition.
+  volatile size_t waiting_count_ GUARDED_BY(task_queue_lock_);
+  std::deque<Task*> tasks_ GUARDED_BY(task_queue_lock_);
+  // TODO: make this immutable/const?
+  std::vector<ThreadPoolWorker*> threads_;
+  // Work balance detection.
+  uint64_t start_time_ GUARDED_BY(task_queue_lock_);
+  uint64_t total_wait_time_;
+  Barrier creation_barier_;
+
+  friend class ThreadPoolWorker;
+  friend class WorkStealingWorker;
+  DISALLOW_COPY_AND_ASSIGN(ThreadPool);
+};
+
+class WorkStealingTask : public Task {
+ public:
+  WorkStealingTask() : ref_count_(0) {
+
+  }
+
+  size_t GetRefCount() const {
+    return ref_count_;
+  }
+
+  virtual void StealFrom(Thread* self, WorkStealingTask* source) = 0;
+
+ private:
+  // How many people are referencing this task.
+  size_t ref_count_;
+
+  friend class WorkStealingWorker;
+};
+
+class WorkStealingWorker : public ThreadPoolWorker {
+ public:
+  virtual ~WorkStealingWorker();
+
+  bool IsRunningTask() const {
+    return task_ != NULL;
+  }
+
+ protected:
+  WorkStealingTask* task_;
+
+  WorkStealingWorker(ThreadPool* thread_pool, const std::string& name, size_t stack_size);
+  virtual void Run();
+
+  friend class WorkStealingThreadPool;
+  DISALLOW_COPY_AND_ASSIGN(WorkStealingWorker);
+};
+
+class WorkStealingThreadPool : public ThreadPool {
+ public:
+  WorkStealingThreadPool(size_t num_threads);
+  virtual ~WorkStealingThreadPool();
+
+ private:
+  Mutex work_steal_lock_;
+  // Which thread we are stealing from (round robin).
+  size_t steal_index_;
+
+  // Find a task to steal from
+  WorkStealingTask* FindTaskToStealFrom(Thread* self) EXCLUSIVE_LOCKS_REQUIRED(work_steal_lock_);
+
+  friend class WorkStealingWorker;
+};
+
+}  // namespace art
+
+#endif  // ART_SRC_THREAD_POOL_H_