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
265
266
267
268
269
270
|
/*
* Atomic operations that C can't guarantee us. Useful for
* resource counting etc..
*
* But use these as seldom as possible since they are much more slower
* than regular operations.
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1996, 97, 99, 2000, 03, 04, 06 by Ralf Baechle
*/
#ifndef _ASM_ATOMIC_H
#define _ASM_ATOMIC_H
#include <linux/irqflags.h>
#include <linux/types.h>
#include <asm/barrier.h>
#include <asm/compiler.h>
#include <asm/cpu-features.h>
#include <asm/cmpxchg.h>
#include <asm/llsc.h>
#include <asm/sync.h>
#include <asm/war.h>
#define ATOMIC_OPS(pfx, type) \
static __always_inline type arch_##pfx##_read(const pfx##_t *v) \
{ \
return READ_ONCE(v->counter); \
} \
\
static __always_inline void arch_##pfx##_set(pfx##_t *v, type i) \
{ \
WRITE_ONCE(v->counter, i); \
} \
\
static __always_inline type \
arch_##pfx##_cmpxchg(pfx##_t *v, type o, type n) \
{ \
return arch_cmpxchg(&v->counter, o, n); \
} \
\
static __always_inline type arch_##pfx##_xchg(pfx##_t *v, type n) \
{ \
return arch_xchg(&v->counter, n); \
}
ATOMIC_OPS(atomic, int)
#ifdef CONFIG_64BIT
# define ATOMIC64_INIT(i) { (i) }
ATOMIC_OPS(atomic64, s64)
#endif
#define ATOMIC_OP(pfx, op, type, c_op, asm_op, ll, sc) \
static __inline__ void arch_##pfx##_##op(type i, pfx##_t * v) \
{ \
type temp; \
\
if (!kernel_uses_llsc) { \
unsigned long flags; \
\
raw_local_irq_save(flags); \
v->counter c_op i; \
raw_local_irq_restore(flags); \
return; \
} \
\
__asm__ __volatile__( \
" .set push \n" \
" .set " MIPS_ISA_LEVEL " \n" \
" " __SYNC(full, loongson3_war) " \n" \
"1: " #ll " %0, %1 # " #pfx "_" #op " \n" \
" " #asm_op " %0, %2 \n" \
" " #sc " %0, %1 \n" \
"\t" __SC_BEQZ "%0, 1b \n" \
" .set pop \n" \
: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter) \
: "Ir" (i) : __LLSC_CLOBBER); \
}
#define ATOMIC_OP_RETURN(pfx, op, type, c_op, asm_op, ll, sc) \
static __inline__ type \
arch_##pfx##_##op##_return_relaxed(type i, pfx##_t * v) \
{ \
type temp, result; \
\
if (!kernel_uses_llsc) { \
unsigned long flags; \
\
raw_local_irq_save(flags); \
result = v->counter; \
result c_op i; \
v->counter = result; \
raw_local_irq_restore(flags); \
return result; \
} \
\
__asm__ __volatile__( \
" .set push \n" \
" .set " MIPS_ISA_LEVEL " \n" \
" " __SYNC(full, loongson3_war) " \n" \
"1: " #ll " %1, %2 # " #pfx "_" #op "_return\n" \
" " #asm_op " %0, %1, %3 \n" \
" " #sc " %0, %2 \n" \
"\t" __SC_BEQZ "%0, 1b \n" \
" " #asm_op " %0, %1, %3 \n" \
" .set pop \n" \
: "=&r" (result), "=&r" (temp), \
"+" GCC_OFF_SMALL_ASM() (v->counter) \
: "Ir" (i) : __LLSC_CLOBBER); \
\
return result; \
}
#define ATOMIC_FETCH_OP(pfx, op, type, c_op, asm_op, ll, sc) \
static __inline__ type \
arch_##pfx##_fetch_##op##_relaxed(type i, pfx##_t * v) \
{ \
int temp, result; \
\
if (!kernel_uses_llsc) { \
unsigned long flags; \
\
raw_local_irq_save(flags); \
result = v->counter; \
v->counter c_op i; \
raw_local_irq_restore(flags); \
return result; \
} \
\
__asm__ __volatile__( \
" .set push \n" \
" .set " MIPS_ISA_LEVEL " \n" \
" " __SYNC(full, loongson3_war) " \n" \
"1: " #ll " %1, %2 # " #pfx "_fetch_" #op "\n" \
" " #asm_op " %0, %1, %3 \n" \
" " #sc " %0, %2 \n" \
"\t" __SC_BEQZ "%0, 1b \n" \
" .set pop \n" \
" move %0, %1 \n" \
: "=&r" (result), "=&r" (temp), \
"+" GCC_OFF_SMALL_ASM() (v->counter) \
: "Ir" (i) : __LLSC_CLOBBER); \
\
return result; \
}
#undef ATOMIC_OPS
#define ATOMIC_OPS(pfx, op, type, c_op, asm_op, ll, sc) \
ATOMIC_OP(pfx, op, type, c_op, asm_op, ll, sc) \
ATOMIC_OP_RETURN(pfx, op, type, c_op, asm_op, ll, sc) \
ATOMIC_FETCH_OP(pfx, op, type, c_op, asm_op, ll, sc)
ATOMIC_OPS(atomic, add, int, +=, addu, ll, sc)
ATOMIC_OPS(atomic, sub, int, -=, subu, ll, sc)
#define arch_atomic_add_return_relaxed arch_atomic_add_return_relaxed
#define arch_atomic_sub_return_relaxed arch_atomic_sub_return_relaxed
#define arch_atomic_fetch_add_relaxed arch_atomic_fetch_add_relaxed
#define arch_atomic_fetch_sub_relaxed arch_atomic_fetch_sub_relaxed
#ifdef CONFIG_64BIT
ATOMIC_OPS(atomic64, add, s64, +=, daddu, lld, scd)
ATOMIC_OPS(atomic64, sub, s64, -=, dsubu, lld, scd)
# define arch_atomic64_add_return_relaxed arch_atomic64_add_return_relaxed
# define arch_atomic64_sub_return_relaxed arch_atomic64_sub_return_relaxed
# define arch_atomic64_fetch_add_relaxed arch_atomic64_fetch_add_relaxed
# define arch_atomic64_fetch_sub_relaxed arch_atomic64_fetch_sub_relaxed
#endif /* CONFIG_64BIT */
#undef ATOMIC_OPS
#define ATOMIC_OPS(pfx, op, type, c_op, asm_op, ll, sc) \
ATOMIC_OP(pfx, op, type, c_op, asm_op, ll, sc) \
ATOMIC_FETCH_OP(pfx, op, type, c_op, asm_op, ll, sc)
ATOMIC_OPS(atomic, and, int, &=, and, ll, sc)
ATOMIC_OPS(atomic, or, int, |=, or, ll, sc)
ATOMIC_OPS(atomic, xor, int, ^=, xor, ll, sc)
#define arch_atomic_fetch_and_relaxed arch_atomic_fetch_and_relaxed
#define arch_atomic_fetch_or_relaxed arch_atomic_fetch_or_relaxed
#define arch_atomic_fetch_xor_relaxed arch_atomic_fetch_xor_relaxed
#ifdef CONFIG_64BIT
ATOMIC_OPS(atomic64, and, s64, &=, and, lld, scd)
ATOMIC_OPS(atomic64, or, s64, |=, or, lld, scd)
ATOMIC_OPS(atomic64, xor, s64, ^=, xor, lld, scd)
# define arch_atomic64_fetch_and_relaxed arch_atomic64_fetch_and_relaxed
# define arch_atomic64_fetch_or_relaxed arch_atomic64_fetch_or_relaxed
# define arch_atomic64_fetch_xor_relaxed arch_atomic64_fetch_xor_relaxed
#endif
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP
/*
* atomic_sub_if_positive - conditionally subtract integer from atomic variable
* @i: integer value to subtract
* @v: pointer of type atomic_t
*
* Atomically test @v and subtract @i if @v is greater or equal than @i.
* The function returns the old value of @v minus @i.
*/
#define ATOMIC_SIP_OP(pfx, type, op, ll, sc) \
static __inline__ int arch_##pfx##_sub_if_positive(type i, pfx##_t * v) \
{ \
type temp, result; \
\
smp_mb__before_atomic(); \
\
if (!kernel_uses_llsc) { \
unsigned long flags; \
\
raw_local_irq_save(flags); \
result = v->counter; \
result -= i; \
if (result >= 0) \
v->counter = result; \
raw_local_irq_restore(flags); \
smp_mb__after_atomic(); \
return result; \
} \
\
__asm__ __volatile__( \
" .set push \n" \
" .set " MIPS_ISA_LEVEL " \n" \
" " __SYNC(full, loongson3_war) " \n" \
"1: " #ll " %1, %2 # atomic_sub_if_positive\n" \
" .set pop \n" \
" " #op " %0, %1, %3 \n" \
" move %1, %0 \n" \
" bltz %0, 2f \n" \
" .set push \n" \
" .set " MIPS_ISA_LEVEL " \n" \
" " #sc " %1, %2 \n" \
" " __SC_BEQZ "%1, 1b \n" \
"2: " __SYNC(full, loongson3_war) " \n" \
" .set pop \n" \
: "=&r" (result), "=&r" (temp), \
"+" GCC_OFF_SMALL_ASM() (v->counter) \
: "Ir" (i) \
: __LLSC_CLOBBER); \
\
/* \
* In the Loongson3 workaround case we already have a \
* completion barrier at 2: above, which is needed due to the \
* bltz that can branch to code outside of the LL/SC loop. As \
* such, we don't need to emit another barrier here. \
*/ \
if (__SYNC_loongson3_war == 0) \
smp_mb__after_atomic(); \
\
return result; \
}
ATOMIC_SIP_OP(atomic, int, subu, ll, sc)
#define arch_atomic_dec_if_positive(v) arch_atomic_sub_if_positive(1, v)
#ifdef CONFIG_64BIT
ATOMIC_SIP_OP(atomic64, s64, dsubu, lld, scd)
#define arch_atomic64_dec_if_positive(v) arch_atomic64_sub_if_positive(1, v)
#endif
#undef ATOMIC_SIP_OP
#endif /* _ASM_ATOMIC_H */
|
