atomic.cc

/* -*- Mode: C++; tab-width: 4; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/*
 *     Copyright 2011 Couchbase, Inc.
 *
 *   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.
 */

#include "config.h"
#include "atomic.hh"

SpinLock::SpinLock() : lock(0) {
    EP_SPINLOCK_CREATED(this);
}

SpinLock::~SpinLock() {
    assert(lock == 0);
    EP_SPINLOCK_DESTROYED(this);
}

void SpinLock::acquire(void) {
   int spin = 0;
   while (!tryAcquire()) {
      ++spin;
      if (spin > 64) {
          sched_yield();
      }
   }

   EP_SPINLOCK_ACQUIRED(this, spin);
}

void SpinLock::release(void) {
    ep_sync_lock_release(&lock);
    EP_SPINLOCK_RELEASED(this);
}