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// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
// vim: ts=8 sw=2 smarttab
/*
* Ceph - scalable distributed file system
*
* Copyright (C) 2011 New Dream Network
*
* This is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License version 2.1, as published by the Free Software
* Foundation. See file COPYING.
*
*/
#include <stdio.h>
#include <pthread.h>
#include "simple_spin.h"
static uint32_t bar = 13;
static uint32_t *foo = &bar;
void simple_spin_lock(simple_spinlock_t *lock)
{
while(1) {
__sync_synchronize();
uint32_t oldval = *lock;
if (oldval == 0) {
if (__sync_bool_compare_and_swap(lock, 0, 1))
return;
}
// delay
for (int i = 0; i < 100000; i++) {
*foo = (*foo * 33) + 17;
}
}
}
void simple_spin_unlock(simple_spinlock_t *lock)
{
__sync_bool_compare_and_swap(lock, 1, 0);
}
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