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
134
|
/*
* Copyright (C) 2014 Regents of the University of California
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, version 2.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#ifndef _ASM_RISCV_CMPXCHG_H
#define _ASM_RISCV_CMPXCHG_H
#include <linux/bug.h>
#include <asm/barrier.h>
#define __xchg(new, ptr, size, asm_or) \
({ \
__typeof__(ptr) __ptr = (ptr); \
__typeof__(new) __new = (new); \
__typeof__(*(ptr)) __ret; \
switch (size) { \
case 4: \
__asm__ __volatile__ ( \
"amoswap.w" #asm_or " %0, %2, %1" \
: "=r" (__ret), "+A" (*__ptr) \
: "r" (__new) \
: "memory"); \
break; \
case 8: \
__asm__ __volatile__ ( \
"amoswap.d" #asm_or " %0, %2, %1" \
: "=r" (__ret), "+A" (*__ptr) \
: "r" (__new) \
: "memory"); \
break; \
default: \
BUILD_BUG(); \
} \
__ret; \
})
#define xchg(ptr, x) (__xchg((x), (ptr), sizeof(*(ptr)), .aqrl))
#define xchg32(ptr, x) \
({ \
BUILD_BUG_ON(sizeof(*(ptr)) != 4); \
xchg((ptr), (x)); \
})
#define xchg64(ptr, x) \
({ \
BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
xchg((ptr), (x)); \
})
/*
* Atomic compare and exchange. Compare OLD with MEM, if identical,
* store NEW in MEM. Return the initial value in MEM. Success is
* indicated by comparing RETURN with OLD.
*/
#define __cmpxchg(ptr, old, new, size, lrb, scb) \
({ \
__typeof__(ptr) __ptr = (ptr); \
__typeof__(*(ptr)) __old = (old); \
__typeof__(*(ptr)) __new = (new); \
__typeof__(*(ptr)) __ret; \
register unsigned int __rc; \
switch (size) { \
case 4: \
__asm__ __volatile__ ( \
"0:" \
"lr.w" #scb " %0, %2\n" \
"bne %0, %z3, 1f\n" \
"sc.w" #lrb " %1, %z4, %2\n" \
"bnez %1, 0b\n" \
"1:" \
: "=&r" (__ret), "=&r" (__rc), "+A" (*__ptr) \
: "rJ" (__old), "rJ" (__new) \
: "memory"); \
break; \
case 8: \
__asm__ __volatile__ ( \
"0:" \
"lr.d" #scb " %0, %2\n" \
"bne %0, %z3, 1f\n" \
"sc.d" #lrb " %1, %z4, %2\n" \
"bnez %1, 0b\n" \
"1:" \
: "=&r" (__ret), "=&r" (__rc), "+A" (*__ptr) \
: "rJ" (__old), "rJ" (__new) \
: "memory"); \
break; \
default: \
BUILD_BUG(); \
} \
__ret; \
})
#define cmpxchg(ptr, o, n) \
(__cmpxchg((ptr), (o), (n), sizeof(*(ptr)), .aqrl, .aqrl))
#define cmpxchg_local(ptr, o, n) \
(__cmpxchg((ptr), (o), (n), sizeof(*(ptr)), , ))
#define cmpxchg32(ptr, o, n) \
({ \
BUILD_BUG_ON(sizeof(*(ptr)) != 4); \
cmpxchg((ptr), (o), (n)); \
})
#define cmpxchg32_local(ptr, o, n) \
({ \
BUILD_BUG_ON(sizeof(*(ptr)) != 4); \
cmpxchg_local((ptr), (o), (n)); \
})
#define cmpxchg64(ptr, o, n) \
({ \
BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
cmpxchg((ptr), (o), (n)); \
})
#define cmpxchg64_local(ptr, o, n) \
({ \
BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
cmpxchg_local((ptr), (o), (n)); \
})
#endif /* _ASM_RISCV_CMPXCHG_H */
|