Subversion Repositories openrisc_2011-10-31

// workqueue-internal.h -- internal work queue header for gold   -*- C++ -*-

// Copyright 2006, 2007, 2008 Free Software Foundation, Inc.

// Written by Ian Lance Taylor <iant@google.com>.

// This file is part of gold.

// This program is free software; you can redistribute it and/or modify

// it under the terms of the GNU General Public License as published by

// the Free Software Foundation; either version 3 of the License, or

// (at your option) any later version.

// This program is distributed in the hope that it will be useful,

// but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License

// along with this program; if not, write to the Free Software

// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,

// MA 02110-1301, USA.

#ifndef GOLD_WORKQUEUE_INTERNAL_H

#define GOLD_WORKQUEUE_INTERNAL_H

#include <queue>

#include <csignal>

#include "gold-threads.h"

#include "workqueue.h"

// This is an internal header file for different gold workqueue

// implementations.

namespace gold

{

class Workqueue_thread;

// The Workqueue_threader abstract class.  This is the interface used

// by the general workqueue code to manage threads.

class Workqueue_threader

{

 public:

  Workqueue_threader(Workqueue* workqueue)

    : workqueue_(workqueue)

  { }

  virtual ~Workqueue_threader()

  { }

  // Set the number of threads to use.  This is ignored when not using

  // threads.

  virtual void

  set_thread_count(int) = 0;

  // Return whether to cancel the current thread.

  virtual bool

  should_cancel_thread() = 0;

 protected:

  // Get the Workqueue.

  Workqueue*

  get_workqueue()

  { return this->workqueue_; }

 private:

  // The Workqueue.

  Workqueue* workqueue_;

};

// The threaded instantiation of Workqueue_threader.

class Workqueue_threader_threadpool : public Workqueue_threader

{

 public:

  Workqueue_threader_threadpool(Workqueue*);

  ~Workqueue_threader_threadpool();

  // Set the thread count.

  void

  set_thread_count(int);

  // Return whether to cancel a thread.

  bool

  should_cancel_thread();

  // Process all tasks.  This keeps running until told to cancel.

  void

  process(int thread_number)

  { this->get_workqueue()->process(thread_number); }

 private:

  // This is set if we need to check the thread count.

  volatile sig_atomic_t check_thread_count_;

  // Lock for the remaining members.

  Lock lock_;

  // The number of threads we want to create.  This is set to zero

  // when all threads should exit.

  int desired_thread_count_;

  // The number of threads currently running.

  int threads_;

};

} // End namespace gold.

#endif // !defined(GOLD_WORKQUEUE_INTERNAL_H)