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
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
|
#ifndef _ALPHA_ATOMIC_H
#define _ALPHA_ATOMIC_H
#include <asm/barrier.h>
/*
* Atomic operations that C can't guarantee us. Useful for
* resource counting etc...
*
* But use these as seldom as possible since they are much slower
* than regular operations.
*/
/*
* Counter is volatile to make sure gcc doesn't try to be clever
* and move things around on us. We need to use _exactly_ the address
* the user gave us, not some alias that contains the same information.
*/
typedef struct { volatile int counter; } atomic_t;
typedef struct { volatile long counter; } atomic64_t;
#define ATOMIC_INIT(i) ( (atomic_t) { (i) } )
#define ATOMIC64_INIT(i) ( (atomic64_t) { (i) } )
#define atomic_read(v) ((v)->counter + 0)
#define atomic64_read(v) ((v)->counter + 0)
#define atomic_set(v,i) ((v)->counter = (i))
#define atomic64_set(v,i) ((v)->counter = (i))
/*
* To get proper branch prediction for the main line, we must branch
* forward to code at the end of this object's .text section, then
* branch back to restart the operation.
*/
static __inline__ void atomic_add(int i, atomic_t * v)
{
unsigned long temp;
__asm__ __volatile__(
"1: ldl_l %0,%1\n"
" addl %0,%2,%0\n"
" stl_c %0,%1\n"
" beq %0,2f\n"
".subsection 2\n"
"2: br 1b\n"
".previous"
:"=&r" (temp), "=m" (v->counter)
:"Ir" (i), "m" (v->counter));
}
static __inline__ void atomic64_add(long i, atomic64_t * v)
{
unsigned long temp;
__asm__ __volatile__(
"1: ldq_l %0,%1\n"
" addq %0,%2,%0\n"
" stq_c %0,%1\n"
" beq %0,2f\n"
".subsection 2\n"
"2: br 1b\n"
".previous"
:"=&r" (temp), "=m" (v->counter)
:"Ir" (i), "m" (v->counter));
}
static __inline__ void atomic_sub(int i, atomic_t * v)
{
unsigned long temp;
__asm__ __volatile__(
"1: ldl_l %0,%1\n"
" subl %0,%2,%0\n"
" stl_c %0,%1\n"
" beq %0,2f\n"
".subsection 2\n"
"2: br 1b\n"
".previous"
:"=&r" (temp), "=m" (v->counter)
:"Ir" (i), "m" (v->counter));
}
static __inline__ void atomic64_sub(long i, atomic64_t * v)
{
unsigned long temp;
__asm__ __volatile__(
"1: ldq_l %0,%1\n"
" subq %0,%2,%0\n"
" stq_c %0,%1\n"
" beq %0,2f\n"
".subsection 2\n"
"2: br 1b\n"
".previous"
:"=&r" (temp), "=m" (v->counter)
:"Ir" (i), "m" (v->counter));
}
/*
* Same as above, but return the result value
*/
static __inline__ long atomic_add_return(int i, atomic_t * v)
{
long temp, result;
smp_mb();
__asm__ __volatile__(
"1: ldl_l %0,%1\n"
" addl %0,%3,%2\n"
" addl %0,%3,%0\n"
" stl_c %0,%1\n"
" beq %0,2f\n"
".subsection 2\n"
"2: br 1b\n"
".previous"
:"=&r" (temp), "=m" (v->counter), "=&r" (result)
:"Ir" (i), "m" (v->counter) : "memory");
smp_mb();
return result;
}
static __inline__ long atomic64_add_return(long i, atomic64_t * v)
{
long temp, result;
smp_mb();
__asm__ __volatile__(
"1: ldq_l %0,%1\n"
" addq %0,%3,%2\n"
" addq %0,%3,%0\n"
" stq_c %0,%1\n"
" beq %0,2f\n"
".subsection 2\n"
"2: br 1b\n"
".previous"
:"=&r" (temp), "=m" (v->counter), "=&r" (result)
:"Ir" (i), "m" (v->counter) : "memory");
smp_mb();
return result;
}
static __inline__ long atomic_sub_return(int i, atomic_t * v)
{
long temp, result;
smp_mb();
__asm__ __volatile__(
"1: ldl_l %0,%1\n"
" subl %0,%3,%2\n"
" subl %0,%3,%0\n"
" stl_c %0,%1\n"
" beq %0,2f\n"
".subsection 2\n"
"2: br 1b\n"
".previous"
:"=&r" (temp), "=m" (v->counter), "=&r" (result)
:"Ir" (i), "m" (v->counter) : "memory");
smp_mb();
return result;
}
static __inline__ long atomic64_sub_return(long i, atomic64_t * v)
{
long temp, result;
smp_mb();
__asm__ __volatile__(
"1: ldq_l %0,%1\n"
" subq %0,%3,%2\n"
" subq %0,%3,%0\n"
" stq_c %0,%1\n"
" beq %0,2f\n"
".subsection 2\n"
"2: br 1b\n"
".previous"
:"=&r" (temp), "=m" (v->counter), "=&r" (result)
:"Ir" (i), "m" (v->counter) : "memory");
smp_mb();
return result;
}
#define atomic64_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), old, new))
#define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
#define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), old, new))
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
/**
* atomic_add_unless - add unless the number is a given value
* @v: pointer of type atomic_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as it was not @u.
* Returns non-zero if @v was not @u, and zero otherwise.
*/
#define atomic_add_unless(v, a, u) \
({ \
__typeof__((v)->counter) c, old; \
c = atomic_read(v); \
for (;;) { \
if (unlikely(c == (u))) \
break; \
old = atomic_cmpxchg((v), c, c + (a)); \
if (likely(old == c)) \
break; \
c = old; \
} \
c != (u); \
})
#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
/**
* atomic64_add_unless - add unless the number is a given value
* @v: pointer of type atomic64_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as it was not @u.
* Returns non-zero if @v was not @u, and zero otherwise.
*/
#define atomic64_add_unless(v, a, u) \
({ \
__typeof__((v)->counter) c, old; \
c = atomic64_read(v); \
for (;;) { \
if (unlikely(c == (u))) \
break; \
old = atomic64_cmpxchg((v), c, c + (a)); \
if (likely(old == c)) \
break; \
c = old; \
} \
c != (u); \
})
#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
#define atomic64_add_negative(a, v) (atomic64_add_return((a), (v)) < 0)
#define atomic_dec_return(v) atomic_sub_return(1,(v))
#define atomic64_dec_return(v) atomic64_sub_return(1,(v))
#define atomic_inc_return(v) atomic_add_return(1,(v))
#define atomic64_inc_return(v) atomic64_add_return(1,(v))
#define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0)
#define atomic64_sub_and_test(i,v) (atomic64_sub_return((i), (v)) == 0)
#define atomic_inc_and_test(v) (atomic_add_return(1, (v)) == 0)
#define atomic64_inc_and_test(v) (atomic64_add_return(1, (v)) == 0)
#define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0)
#define atomic64_dec_and_test(v) (atomic64_sub_return(1, (v)) == 0)
#define atomic_inc(v) atomic_add(1,(v))
#define atomic64_inc(v) atomic64_add(1,(v))
#define atomic_dec(v) atomic_sub(1,(v))
#define atomic64_dec(v) atomic64_sub(1,(v))
#define smp_mb__before_atomic_dec() smp_mb()
#define smp_mb__after_atomic_dec() smp_mb()
#define smp_mb__before_atomic_inc() smp_mb()
#define smp_mb__after_atomic_inc() smp_mb()
#include <asm-generic/atomic.h>
#endif /* _ALPHA_ATOMIC_H */
|
