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
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
|
/*
* Copyright 2010 Tilera Corporation. All Rights Reserved.
*
* 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, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for
* more details.
*
* Atomic primitives.
*/
#ifndef _ASM_TILE_ATOMIC_H
#define _ASM_TILE_ATOMIC_H
#include <asm/cmpxchg.h>
#ifndef __ASSEMBLY__
#include <linux/compiler.h>
#include <linux/types.h>
#define ATOMIC_INIT(i) { (i) }
/**
* atomic_read - read atomic variable
* @v: pointer of type atomic_t
*
* Atomically reads the value of @v.
*/
static inline int atomic_read(const atomic_t *v)
{
return READ_ONCE(v->counter);
}
/**
* atomic_sub_return - subtract integer and return
* @v: pointer of type atomic_t
* @i: integer value to subtract
*
* Atomically subtracts @i from @v and returns @v - @i
*/
#define atomic_sub_return(i, v) atomic_add_return((int)(-(i)), (v))
#define atomic_fetch_sub(i, v) atomic_fetch_add(-(int)(i), (v))
/**
* atomic_sub - subtract integer from atomic variable
* @i: integer value to subtract
* @v: pointer of type atomic_t
*
* Atomically subtracts @i from @v.
*/
#define atomic_sub(i, v) atomic_add((int)(-(i)), (v))
/**
* atomic_sub_and_test - subtract value from variable and test result
* @i: integer value to subtract
* @v: pointer of type atomic_t
*
* Atomically subtracts @i from @v and returns true if the result is
* zero, or false for all other cases.
*/
#define atomic_sub_and_test(i, v) (atomic_sub_return((i), (v)) == 0)
/**
* atomic_inc_return - increment memory and return
* @v: pointer of type atomic_t
*
* Atomically increments @v by 1 and returns the new value.
*/
#define atomic_inc_return(v) atomic_add_return(1, (v))
/**
* atomic_dec_return - decrement memory and return
* @v: pointer of type atomic_t
*
* Atomically decrements @v by 1 and returns the new value.
*/
#define atomic_dec_return(v) atomic_sub_return(1, (v))
/**
* atomic_inc - increment atomic variable
* @v: pointer of type atomic_t
*
* Atomically increments @v by 1.
*/
#define atomic_inc(v) atomic_add(1, (v))
/**
* atomic_dec - decrement atomic variable
* @v: pointer of type atomic_t
*
* Atomically decrements @v by 1.
*/
#define atomic_dec(v) atomic_sub(1, (v))
/**
* atomic_dec_and_test - decrement and test
* @v: pointer of type atomic_t
*
* Atomically decrements @v by 1 and returns true if the result is 0.
*/
#define atomic_dec_and_test(v) (atomic_dec_return(v) == 0)
/**
* atomic_inc_and_test - increment and test
* @v: pointer of type atomic_t
*
* Atomically increments @v by 1 and returns true if the result is 0.
*/
#define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)
/**
* atomic_xchg - atomically exchange contents of memory with a new value
* @v: pointer of type atomic_t
* @i: integer value to store in memory
*
* Atomically sets @v to @i and returns old @v
*/
static inline int atomic_xchg(atomic_t *v, int n)
{
return xchg(&v->counter, n);
}
/**
* atomic_cmpxchg - atomically exchange contents of memory if it matches
* @v: pointer of type atomic_t
* @o: old value that memory should have
* @n: new value to write to memory if it matches
*
* Atomically checks if @v holds @o and replaces it with @n if so.
* Returns the old value at @v.
*/
static inline int atomic_cmpxchg(atomic_t *v, int o, int n)
{
return cmpxchg(&v->counter, o, n);
}
/**
* atomic_add_negative - add and test if negative
* @v: pointer of type atomic_t
* @i: integer value to add
*
* Atomically adds @i to @v and returns true if the result is
* negative, or false when result is greater than or equal to zero.
*/
#define atomic_add_negative(i, v) (atomic_add_return((i), (v)) < 0)
#endif /* __ASSEMBLY__ */
#ifndef __tilegx__
#include <asm/atomic_32.h>
#else
#include <asm/atomic_64.h>
#endif
#ifndef __ASSEMBLY__
/**
* atomic64_xchg - atomically exchange contents of memory with a new value
* @v: pointer of type atomic64_t
* @i: integer value to store in memory
*
* Atomically sets @v to @i and returns old @v
*/
static inline long long atomic64_xchg(atomic64_t *v, long long n)
{
return xchg64(&v->counter, n);
}
/**
* atomic64_cmpxchg - atomically exchange contents of memory if it matches
* @v: pointer of type atomic64_t
* @o: old value that memory should have
* @n: new value to write to memory if it matches
*
* Atomically checks if @v holds @o and replaces it with @n if so.
* Returns the old value at @v.
*/
static inline long long atomic64_cmpxchg(atomic64_t *v, long long o,
long long n)
{
return cmpxchg64(&v->counter, o, n);
}
static inline long long atomic64_dec_if_positive(atomic64_t *v)
{
long long c, old, dec;
c = atomic64_read(v);
for (;;) {
dec = c - 1;
if (unlikely(dec < 0))
break;
old = atomic64_cmpxchg((v), c, dec);
if (likely(old == c))
break;
c = old;
}
return dec;
}
#endif /* __ASSEMBLY__ */
#endif /* _ASM_TILE_ATOMIC_H */
|
