linux/sound/core/seq/seq_lock.c

49 lines
1.5 KiB
C
Raw Normal View History

/*
* Do sleep inside a spin-lock
* Copyright (c) 1999 by Takashi Iwai <tiwai@suse.de>
*
*
* 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
*
*/
#include <sound/core.h>
#include "seq_lock.h"
#if defined(CONFIG_SMP) || defined(CONFIG_SND_DEBUG)
/* wait until all locks are released */
void snd_use_lock_sync_helper(snd_use_lock_t *lockp, const char *file, int line)
{
int max_count = 5 * HZ;
if (atomic_read(lockp) < 0) {
printk(KERN_WARNING "seq_lock: lock trouble [counter = %d] in %s:%d\n", atomic_read(lockp), file, line);
return;
}
while (atomic_read(lockp) > 0) {
if (max_count == 0) {
snd_printk(KERN_WARNING "seq_lock: timeout [%d left] in %s:%d\n", atomic_read(lockp), file, line);
break;
}
schedule_timeout_uninterruptible(1);
max_count--;
}
}
EXPORT_SYMBOL(snd_use_lock_sync_helper);
#endif