atomic_64.S revision 193d2aadc0ff5c687f6f0d5ef1d38c86ab511a14 
1/* atomic.S: These things are too big to do inline.
2 *
3 * Copyright (C) 1999, 2007 2012 David S. Miller (davem@davemloft.net)
4 */
5
6#include <linux/linkage.h>
7#include <asm/asi.h>
8#include <asm/backoff.h>
9
10	.text
11
12	/* Two versions of the atomic routines, one that
13	 * does not return a value and does not perform
14	 * memory barriers, and a second which returns
15	 * a value and does the barriers.
16	 */
17ENTRY(atomic_add) /* %o0 = increment, %o1 = atomic_ptr */
18	BACKOFF_SETUP(%o2)
191:	lduw	[%o1], %g1
20	add	%g1, %o0, %g7
21	cas	[%o1], %g1, %g7
22	cmp	%g1, %g7
23	bne,pn	%icc, BACKOFF_LABEL(2f, 1b)
24	 nop
25	retl
26	 nop
272:	BACKOFF_SPIN(%o2, %o3, 1b)
28ENDPROC(atomic_add)
29
30ENTRY(atomic_sub) /* %o0 = decrement, %o1 = atomic_ptr */
31	BACKOFF_SETUP(%o2)
321:	lduw	[%o1], %g1
33	sub	%g1, %o0, %g7
34	cas	[%o1], %g1, %g7
35	cmp	%g1, %g7
36	bne,pn	%icc, BACKOFF_LABEL(2f, 1b)
37	 nop
38	retl
39	 nop
402:	BACKOFF_SPIN(%o2, %o3, 1b)
41ENDPROC(atomic_sub)
42
43ENTRY(atomic_add_ret) /* %o0 = increment, %o1 = atomic_ptr */
44	BACKOFF_SETUP(%o2)
451:	lduw	[%o1], %g1
46	add	%g1, %o0, %g7
47	cas	[%o1], %g1, %g7
48	cmp	%g1, %g7
49	bne,pn	%icc, BACKOFF_LABEL(2f, 1b)
50	 add	%g1, %o0, %g1
51	retl
52	 sra	%g1, 0, %o0
532:	BACKOFF_SPIN(%o2, %o3, 1b)
54ENDPROC(atomic_add_ret)
55
56ENTRY(atomic_sub_ret) /* %o0 = decrement, %o1 = atomic_ptr */
57	BACKOFF_SETUP(%o2)
581:	lduw	[%o1], %g1
59	sub	%g1, %o0, %g7
60	cas	[%o1], %g1, %g7
61	cmp	%g1, %g7
62	bne,pn	%icc, BACKOFF_LABEL(2f, 1b)
63	 sub	%g1, %o0, %g1
64	retl
65	 sra	%g1, 0, %o0
662:	BACKOFF_SPIN(%o2, %o3, 1b)
67ENDPROC(atomic_sub_ret)
68
69ENTRY(atomic64_add) /* %o0 = increment, %o1 = atomic_ptr */
70	BACKOFF_SETUP(%o2)
711:	ldx	[%o1], %g1
72	add	%g1, %o0, %g7
73	casx	[%o1], %g1, %g7
74	cmp	%g1, %g7
75	bne,pn	%xcc, BACKOFF_LABEL(2f, 1b)
76	 nop
77	retl
78	 nop
792:	BACKOFF_SPIN(%o2, %o3, 1b)
80ENDPROC(atomic64_add)
81
82ENTRY(atomic64_sub) /* %o0 = decrement, %o1 = atomic_ptr */
83	BACKOFF_SETUP(%o2)
841:	ldx	[%o1], %g1
85	sub	%g1, %o0, %g7
86	casx	[%o1], %g1, %g7
87	cmp	%g1, %g7
88	bne,pn	%xcc, BACKOFF_LABEL(2f, 1b)
89	 nop
90	retl
91	 nop
922:	BACKOFF_SPIN(%o2, %o3, 1b)
93ENDPROC(atomic64_sub)
94
95ENTRY(atomic64_add_ret) /* %o0 = increment, %o1 = atomic_ptr */
96	BACKOFF_SETUP(%o2)
971:	ldx	[%o1], %g1
98	add	%g1, %o0, %g7
99	casx	[%o1], %g1, %g7
100	cmp	%g1, %g7
101	bne,pn	%xcc, BACKOFF_LABEL(2f, 1b)
102	 nop
103	retl
104	 add	%g1, %o0, %o0
1052:	BACKOFF_SPIN(%o2, %o3, 1b)
106ENDPROC(atomic64_add_ret)
107
108ENTRY(atomic64_sub_ret) /* %o0 = decrement, %o1 = atomic_ptr */
109	BACKOFF_SETUP(%o2)
1101:	ldx	[%o1], %g1
111	sub	%g1, %o0, %g7
112	casx	[%o1], %g1, %g7
113	cmp	%g1, %g7
114	bne,pn	%xcc, BACKOFF_LABEL(2f, 1b)
115	 nop
116	retl
117	 sub	%g1, %o0, %o0
1182:	BACKOFF_SPIN(%o2, %o3, 1b)
119ENDPROC(atomic64_sub_ret)
120
121ENTRY(atomic64_dec_if_positive) /* %o0 = atomic_ptr */
122	BACKOFF_SETUP(%o2)
1231:	ldx	[%o0], %g1
124	brlez,pn %g1, 3f
125	 sub	%g1, 1, %g7
126	casx	[%o0], %g1, %g7
127	cmp	%g1, %g7
128	bne,pn	%xcc, BACKOFF_LABEL(2f, 1b)
129	 nop
1303:	retl
131	 sub	%g1, 1, %o0
1322:	BACKOFF_SPIN(%o2, %o3, 1b)
133ENDPROC(atomic64_dec_if_positive)
134