1/*
2 * arch/alpha/lib/dec_and_lock.c
3 *
4 * ll/sc version of atomic_dec_and_lock()
5 *
6 */
7
8#include <linux/spinlock.h>
9#include <asm/atomic.h>
10
11  asm (".text					\n\
12	.global atomic_dec_and_lock		\n\
13	.ent atomic_dec_and_lock		\n\
14	.align	4				\n\
15atomic_dec_and_lock:				\n\
16	.prologue 0				\n\
171:	ldl_l	$1, 0($16)			\n\
18	subl	$1, 1, $1			\n\
19	beq	$1, 2f				\n\
20	stl_c	$1, 0($16)			\n\
21	beq	$1, 4f				\n\
22	mb					\n\
23	clr	$0				\n\
24	ret					\n\
252:	br	$29, 3f				\n\
263:	ldgp	$29, 0($29)			\n\
27	br	$atomic_dec_and_lock_1..ng	\n\
28	.subsection 2				\n\
294:	br	1b				\n\
30	.previous				\n\
31	.end atomic_dec_and_lock");
32
33static int __attribute__((unused))
34atomic_dec_and_lock_1(atomic_t *atomic, spinlock_t *lock)
35{
36	/* Slow path */
37	spin_lock(lock);
38	if (atomic_dec_and_test(atomic))
39		return 1;
40	spin_unlock(lock);
41	return 0;
42}
43