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/*
* Copyright (c) 2000 Silicon Graphics, Inc. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*
* Further, this software is distributed without any warranty that it is
* free of the rightful claim of any third person regarding infringement
* or the like. Any license provided herein, whether implied or
* otherwise, applies only to this software file. Patent licenses, if
* any, provided herein do not apply to combinations of this program with
* other software, or any other product whatsoever.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write the Free Software Foundation, Inc., 59
* Temple Place - Suite 330, Boston MA 02111-1307, USA.
*
* Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
* Mountain View, CA 94043, or:
*
* http://www.sgi.com
*
* For further information regarding this notice, see:
*
* http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
*/
#include <linux/time.h>
#include <linux/sched.h>
#include <asm/system.h>
#include <linux/interrupt.h>
#include <asm/current.h>
#include <linux/module.h> /* for EXPORT_SYMBOL */
#include <linux/xfs_support/support.h>
/* Synchronisation variables ---------------------------------------- */
void _sv_init( sv_t *sv)
{
init_waitqueue_head( &sv->waiters );
spin_lock_init(&sv->lock);
}
void _sv_wait( sv_t *sv, spinlock_t *lock, int spl, int intr, struct timespec *timeout)
{
DECLARE_WAITQUEUE( wait, current );
spin_lock(&sv->lock); /* No need to do interrupts since
they better be disabled */
/* Don't restore interrupts until we are done with both locks */
spin_unlock( lock );
add_wait_queue_exclusive( &sv->waiters, &wait );
#if 0
if (intr) {
set_current_state(TASK_INTERRUPTIBLE | TASK_EXCLUSIVE);
} else {
set_current_state(TASK_UNINTERRUPTIBLE | TASK_EXCLUSIVE);
}
#endif
if (intr) {
set_current_state(TASK_INTERRUPTIBLE );
} else {
set_current_state(TASK_UNINTERRUPTIBLE );
}
spin_unlock_irqrestore( & sv->lock, (long)spl );
if (timeout) {
schedule_timeout(timespec_to_jiffies(timeout));
} else {
schedule();
}
set_current_state(TASK_RUNNING);
remove_wait_queue( &sv->waiters, &wait );
}
void
_sv_broadcast(sv_t *sv)
{
unsigned long flags;
spin_lock_irqsave(&sv->lock, flags);
wake_up_all(&sv->waiters );
spin_unlock_irqrestore(&sv->lock, flags);
}
/*
* Set runnable, at most, one thread waiting on sync variable.
* Returns # of threads set runnable (0 or 1).
*/
void
_sv_signal(sv_t *svp)
{
unsigned long flags;
spin_lock_irqsave(&svp->lock, flags);
wake_up(&svp->waiters);
spin_unlock_irqrestore(&svp->lock, flags);
}
EXPORT_SYMBOL(_sv_init);
EXPORT_SYMBOL(_sv_wait);
EXPORT_SYMBOL(_sv_broadcast);
EXPORT_SYMBOL(_sv_signal);
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