Name TaskScheduler's worker threads

base/task_scheduler/scheduler_thread_pool_impl.h

 // Copyright 2016 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.
 
 #ifndef BASE_TASK_SCHEDULER_SCHEDULER_THREAD_POOL_IMPL_H_
 #define BASE_TASK_SCHEDULER_SCHEDULER_THREAD_POOL_IMPL_H_
 
 #include <stddef.h>
 
 #include <memory>
+#include <string>
 #include <vector>
 
 #include "base/base_export.h"
 #include "base/callback.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
+#include "base/strings/string_piece.h"
 #include "base/synchronization/condition_variable.h"
 #include "base/task_runner.h"
 #include "base/task_scheduler/priority_queue.h"
 #include "base/task_scheduler/scheduler_lock.h"
 #include "base/task_scheduler/scheduler_thread_pool.h"
 #include "base/task_scheduler/scheduler_worker_thread.h"
 #include "base/task_scheduler/scheduler_worker_thread_stack.h"
 #include "base/task_scheduler/sequence.h"
 #include "base/task_scheduler/task.h"
 #include "base/task_scheduler/task_traits.h"
@@ skipping 15 matching lines @@
 
   // Callback invoked when a Sequence isn't empty after a worker thread pops a
   // Task from it.
   using ReEnqueueSequenceCallback = Callback<void(scoped_refptr<Sequence>)>;
 
   // Destroying a SchedulerThreadPool returned by CreateThreadPool() is not
   // allowed in production; it is always leaked. In tests, it can only be
   // destroyed after JoinForTesting() has returned.
   ~SchedulerThreadPoolImpl() override;
 
-  // Creates a SchedulerThreadPool with up to |max_threads| threads of priority
-  // |thread_priority|. |io_restriction| indicates whether Tasks on the
-  // constructed thread pool are allowed to make I/O calls.
+  // Creates a SchedulerThreadPool labeled |name| with up to |max_threads|
+  // threads of priority |thread_priority|. |io_restriction| indicates whether
+  // Tasks on the constructed thread pool are allowed to make I/O calls.
   // |re_enqueue_sequence_callback| will be invoked after a thread of this
   // thread pool tries to run a Task. |task_tracker| is used to handle shutdown
   // behavior of Tasks. |delayed_task_manager| handles Tasks posted with a
   // delay. Returns nullptr on failure to create a thread pool with at least one
   // thread.
   static std::unique_ptr<SchedulerThreadPoolImpl> Create(
+      StringPiece name,
       ThreadPriority thread_priority,
       size_t max_threads,
       IORestriction io_restriction,
       const ReEnqueueSequenceCallback& re_enqueue_sequence_callback,
       TaskTracker* task_tracker,
       DelayedTaskManager* delayed_task_manager);
 
   // Waits until all threads are idle.
   void WaitForAllWorkerThreadsIdleForTesting();
 
@@ skipping 10 matching lines @@
   bool PostTaskWithSequence(std::unique_ptr<Task> task,
                             scoped_refptr<Sequence> sequence,
                             SchedulerWorkerThread* worker_thread) override;
   void PostTaskWithSequenceNow(std::unique_ptr<Task> task,
                                scoped_refptr<Sequence> sequence,
                                SchedulerWorkerThread* worker_thread) override;
 
  private:
   class SchedulerWorkerThreadDelegateImpl;
 
-  SchedulerThreadPoolImpl(IORestriction io_restriction,
+  SchedulerThreadPoolImpl(StringPiece name,
+                          IORestriction io_restriction,
                           TaskTracker* task_tracker,
                           DelayedTaskManager* delayed_task_manager);
 
   bool Initialize(
       ThreadPriority thread_priority,
       size_t max_threads,
       const ReEnqueueSequenceCallback& re_enqueue_sequence_callback);
 
   // Wakes up the last thread from this thread pool to go idle, if any.
   void WakeUpOneThread();
 
   // Adds |worker_thread| to |idle_worker_threads_stack_|.
   void AddToIdleWorkerThreadsStack(SchedulerWorkerThread* worker_thread);
 
   // Removes |worker_thread| from |idle_worker_threads_stack_|.
   void RemoveFromIdleWorkerThreadsStack(SchedulerWorkerThread* worker_thread);
 
+  // The name of this thread pool, used to label its worker threads.
+  const std::string name_;
+
   // All worker threads owned by this thread pool. Only modified during
   // initialization of the thread pool.
   std::vector<std::unique_ptr<SchedulerWorkerThread>> worker_threads_;
 
   // Synchronizes access to |next_worker_thread_index_|.
   SchedulerLock next_worker_thread_index_lock_;
 
   // Index of the worker thread that will be assigned to the next single-
   // threaded TaskRunner returned by this pool.
   size_t next_worker_thread_index_ = 0;
@@ skipping 28 matching lines @@
   TaskTracker* const task_tracker_;
   DelayedTaskManager* const delayed_task_manager_;
 
   DISALLOW_COPY_AND_ASSIGN(SchedulerThreadPoolImpl);
 };
 
 }  // namespace internal
 }  // namespace base
 
 #endif  // BASE_TASK_SCHEDULER_SCHEDULER_THREAD_POOL_IMPL_H_