aboutsummaryrefslogtreecommitdiff
path: root/arch/sparc/lib/atomic_64.S
blob: 85c233d0a34003d551587c7c378bd813f64712fe (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
/* atomic.S: These things are too big to do inline.
 *
 * Copyright (C) 1999, 2007 2012 David S. Miller (davem@davemloft.net)
 */

#include <linux/linkage.h>
#include <asm/asi.h>
#include <asm/backoff.h>

	.text

	/* Two versions of the atomic routines, one that
	 * does not return a value and does not perform
	 * memory barriers, and a second which returns
	 * a value and does the barriers.
	 */
ENTRY(atomic_add) /* %o0 = increment, %o1 = atomic_ptr */
	BACKOFF_SETUP(%o2)
1:	lduw	[%o1], %g1
	add	%g1, %o0, %g7
	cas	[%o1], %g1, %g7
	cmp	%g1, %g7
	bne,pn	%icc, BACKOFF_LABEL(2f, 1b)
	 nop
	retl
	 nop
2:	BACKOFF_SPIN(%o2, %o3, 1b)
ENDPROC(atomic_add)

ENTRY(atomic_sub) /* %o0 = decrement, %o1 = atomic_ptr */
	BACKOFF_SETUP(%o2)
1:	lduw	[%o1], %g1
	sub	%g1, %o0, %g7
	cas	[%o1], %g1, %g7
	cmp	%g1, %g7
	bne,pn	%icc, BACKOFF_LABEL(2f, 1b)
	 nop
	retl
	 nop
2:	BACKOFF_SPIN(%o2, %o3, 1b)
ENDPROC(atomic_sub)

ENTRY(atomic_add_ret) /* %o0 = increment, %o1 = atomic_ptr */
	BACKOFF_SETUP(%o2)
1:	lduw	[%o1], %g1
	add	%g1, %o0, %g7
	cas	[%o1], %g1, %g7
	cmp	%g1, %g7
	bne,pn	%icc, BACKOFF_LABEL(2f, 1b)
	 add	%g1, %o0, %g1
	retl
	 sra	%g1, 0, %o0
2:	BACKOFF_SPIN(%o2, %o3, 1b)
ENDPROC(atomic_add_ret)

ENTRY(atomic_sub_ret) /* %o0 = decrement, %o1 = atomic_ptr */
	BACKOFF_SETUP(%o2)
1:	lduw	[%o1], %g1
	sub	%g1, %o0, %g7
	cas	[%o1], %g1, %g7
	cmp	%g1, %g7
	bne,pn	%icc, BACKOFF_LABEL(2f, 1b)
	 sub	%g1, %o0, %g1
	retl
	 sra	%g1, 0, %o0
2:	BACKOFF_SPIN(%o2, %o3, 1b)
ENDPROC(atomic_sub_ret)

ENTRY(atomic64_add) /* %o0 = increment, %o1 = atomic_ptr */
	BACKOFF_SETUP(%o2)
1:	ldx	[%o1], %g1
	add	%g1, %o0, %g7
	casx	[%o1], %g1, %g7
	cmp	%g1, %g7
	bne,pn	%xcc, BACKOFF_LABEL(2f, 1b)
	 nop
	retl
	 nop
2:	BACKOFF_SPIN(%o2, %o3, 1b)
ENDPROC(atomic64_add)

ENTRY(atomic64_sub) /* %o0 = decrement, %o1 = atomic_ptr */
	BACKOFF_SETUP(%o2)
1:	ldx	[%o1], %g1
	sub	%g1, %o0, %g7
	casx	[%o1], %g1, %g7
	cmp	%g1, %g7
	bne,pn	%xcc, BACKOFF_LABEL(2f, 1b)
	 nop
	retl
	 nop
2:	BACKOFF_SPIN(%o2, %o3, 1b)
ENDPROC(atomic64_sub)

ENTRY(atomic64_add_ret) /* %o0 = increment, %o1 = atomic_ptr */
	BACKOFF_SETUP(%o2)
1:	ldx	[%o1], %g1
	add	%g1, %o0, %g7
	casx	[%o1], %g1, %g7
	cmp	%g1, %g7
	bne,pn	%xcc, BACKOFF_LABEL(2f, 1b)
	 nop
	retl
	 add	%g1, %o0, %o0
2:	BACKOFF_SPIN(%o2, %o3, 1b)
ENDPROC(atomic64_add_ret)

ENTRY(atomic64_sub_ret) /* %o0 = decrement, %o1 = atomic_ptr */
	BACKOFF_SETUP(%o2)
1:	ldx	[%o1], %g1
	sub	%g1, %o0, %g7
	casx	[%o1], %g1, %g7
	cmp	%g1, %g7
	bne,pn	%xcc, BACKOFF_LABEL(2f, 1b)
	 nop
	retl
	 sub	%g1, %o0, %o0
2:	BACKOFF_SPIN(%o2, %o3, 1b)
ENDPROC(atomic64_sub_ret)

ENTRY(atomic64_dec_if_positive) /* %o0 = atomic_ptr */
	BACKOFF_SETUP(%o2)
1:	ldx	[%o0], %g1
	brlez,pn %g1, 3f
	 sub	%g1, 1, %g7
	casx	[%o0], %g1, %g7
	cmp	%g1, %g7
	bne,pn	%xcc, BACKOFF_LABEL(2f, 1b)
	 nop
3:	retl
	 sub	%g1, 1, %o0
2:	BACKOFF_SPIN(%o2, %o3, 1b)
ENDPROC(atomic64_dec_if_positive)