shared_polling.hpp

Go to the documentation of this file.

/*
 * Copyright (c) 2014-2015, Hewlett-Packard Development Company, LP.
 * 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 2 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 * HP designates this particular file as subject to the "Classpath" exception
 * as provided by HP in the LICENSE.txt file that accompanied this code.
 */
#ifndef FOEDUS_SOC_SHARED_POLLING_HPP_
#define FOEDUS_SOC_SHARED_POLLING_HPP_

#include <stdint.h>

#include "foedus/cxx11.hpp"

namespace foedus {
namespace soc {

const uint64_t kDefaultPollingSpins = (1ULL << 10);
const uint64_t kDefaultPollingMaxIntervalUs = (1ULL << 15);
const uint64_t kInitialPollingIntervalUs = (1ULL << 8);

class SharedPolling CXX11_FINAL {
 public:
  SharedPolling() { initialize(); }

  // Disable copy constructors
  SharedPolling(const SharedPolling&) CXX11_FUNC_DELETE;
  SharedPolling& operator=(const SharedPolling&) CXX11_FUNC_DELETE;

  void initialize();

  uint64_t  acquire_ticket() const;

  void wait(
    uint64_t demanded_ticket,
    uint64_t polling_spins = kDefaultPollingSpins,
    uint64_t max_interval_us = kDefaultPollingMaxIntervalUs) const;

  bool timedwait(
    uint64_t demanded_ticket,
    uint64_t timeout_microsec,
    uint64_t polling_spins = kDefaultPollingSpins,
    uint64_t max_interval_us = kDefaultPollingMaxIntervalUs) const;

  void signal();

 private:
  uint64_t  cur_ticket_;

  void spin_poll(uint64_t demanded_ticket, uint64_t polling_spins) const;
};
}  // namespace soc
}  // namespace foedus
#endif  // FOEDUS_SOC_SHARED_POLLING_HPP_