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/*
* Atomic read/write
* Copyright (c) 2001 by Abramo Bagnara <abramo@alsa-project.org>
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <stdlib.h>
#include <time.h>
#include <sched.h>
#include "iatomic.h"
void snd_atomic_read_wait(snd_atomic_read_t *t)
{
volatile const snd_atomic_write_t *w = t->write;
unsigned int loops = 0;
struct timespec ts;
while (w->begin != w->end) {
if (loops < MAX_SPIN_COUNT) {
sched_yield();
loops++;
continue;
}
loops = 0;
ts.tv_sec = 0;
ts.tv_nsec = SPIN_SLEEP_DURATION;
nanosleep(&ts, NULL);
}
}
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