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05 April 2024, 19:05:47 UTC
Revision e460b73c8790bb14959cc99a8eb040e6bd2ecbf0 authored by Yoichi Yuasa on 28 May 2007, 13:54:28 UTC, committed by Ralf Baechle on 26 June 2007, 17:57:33 UTC 
[MIPS] remove "support for" from system type entry
 
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
1 parent 2ec0e59
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Tip revision: e460b73c8790bb14959cc99a8eb040e6bd2ecbf0 authored by Yoichi Yuasa on 28 May 2007, 13:54:28 UTC
[MIPS] remove "support for" from system type entry
Tip revision: e460b73
dec_and_lock.c 
#include <linux/module.h>
#include <linux/spinlock.h>
#include <asm/atomic.h>

/*
 * This is an implementation of the notion of "decrement a
 * reference count, and return locked if it decremented to zero".
 *
 * NOTE NOTE NOTE! This is _not_ equivalent to
 *
 *	if (atomic_dec_and_test(&atomic)) {
 *		spin_lock(&lock);
 *		return 1;
 *	}
 *	return 0;
 *
 * because the spin-lock and the decrement must be
 * "atomic".
 */
int _atomic_dec_and_lock(atomic_t *atomic, spinlock_t *lock)
{
#ifdef CONFIG_SMP
	/* Subtract 1 from counter unless that drops it to 0 (ie. it was 1) */
	if (atomic_add_unless(atomic, -1, 1))
		return 0;
#endif
	/* Otherwise do it the slow way */
	spin_lock(lock);
	if (atomic_dec_and_test(atomic))
		return 1;
	spin_unlock(lock);
	return 0;
}

EXPORT_SYMBOL(_atomic_dec_and_lock);
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