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-rw-r--r--include/asm-x86/atomic_32.h259
1 files changed, 0 insertions, 259 deletions
diff --git a/include/asm-x86/atomic_32.h b/include/asm-x86/atomic_32.h
deleted file mode 100644
index 14d3f0beb889..000000000000
--- a/include/asm-x86/atomic_32.h
+++ /dev/null
@@ -1,259 +0,0 @@
1#ifndef ASM_X86__ATOMIC_32_H
2#define ASM_X86__ATOMIC_32_H
3
4#include <linux/compiler.h>
5#include <asm/processor.h>
6#include <asm/cmpxchg.h>
7
8/*
9 * Atomic operations that C can't guarantee us. Useful for
10 * resource counting etc..
11 */
12
13/*
14 * Make sure gcc doesn't try to be clever and move things around
15 * on us. We need to use _exactly_ the address the user gave us,
16 * not some alias that contains the same information.
17 */
18typedef struct {
19 int counter;
20} atomic_t;
21
22#define ATOMIC_INIT(i) { (i) }
23
24/**
25 * atomic_read - read atomic variable
26 * @v: pointer of type atomic_t
27 *
28 * Atomically reads the value of @v.
29 */
30#define atomic_read(v) ((v)->counter)
31
32/**
33 * atomic_set - set atomic variable
34 * @v: pointer of type atomic_t
35 * @i: required value
36 *
37 * Atomically sets the value of @v to @i.
38 */
39#define atomic_set(v, i) (((v)->counter) = (i))
40
41/**
42 * atomic_add - add integer to atomic variable
43 * @i: integer value to add
44 * @v: pointer of type atomic_t
45 *
46 * Atomically adds @i to @v.
47 */
48static inline void atomic_add(int i, atomic_t *v)
49{
50 asm volatile(LOCK_PREFIX "addl %1,%0"
51 : "+m" (v->counter)
52 : "ir" (i));
53}
54
55/**
56 * atomic_sub - subtract integer from atomic variable
57 * @i: integer value to subtract
58 * @v: pointer of type atomic_t
59 *
60 * Atomically subtracts @i from @v.
61 */
62static inline void atomic_sub(int i, atomic_t *v)
63{
64 asm volatile(LOCK_PREFIX "subl %1,%0"
65 : "+m" (v->counter)
66 : "ir" (i));
67}
68
69/**
70 * atomic_sub_and_test - subtract value from variable and test result
71 * @i: integer value to subtract
72 * @v: pointer of type atomic_t
73 *
74 * Atomically subtracts @i from @v and returns
75 * true if the result is zero, or false for all
76 * other cases.
77 */
78static inline int atomic_sub_and_test(int i, atomic_t *v)
79{
80 unsigned char c;
81
82 asm volatile(LOCK_PREFIX "subl %2,%0; sete %1"
83 : "+m" (v->counter), "=qm" (c)
84 : "ir" (i) : "memory");
85 return c;
86}
87
88/**
89 * atomic_inc - increment atomic variable
90 * @v: pointer of type atomic_t
91 *
92 * Atomically increments @v by 1.
93 */
94static inline void atomic_inc(atomic_t *v)
95{
96 asm volatile(LOCK_PREFIX "incl %0"
97 : "+m" (v->counter));
98}
99
100/**
101 * atomic_dec - decrement atomic variable
102 * @v: pointer of type atomic_t
103 *
104 * Atomically decrements @v by 1.
105 */
106static inline void atomic_dec(atomic_t *v)
107{
108 asm volatile(LOCK_PREFIX "decl %0"
109 : "+m" (v->counter));
110}
111
112/**
113 * atomic_dec_and_test - decrement and test
114 * @v: pointer of type atomic_t
115 *
116 * Atomically decrements @v by 1 and
117 * returns true if the result is 0, or false for all other
118 * cases.
119 */
120static inline int atomic_dec_and_test(atomic_t *v)
121{
122 unsigned char c;
123
124 asm volatile(LOCK_PREFIX "decl %0; sete %1"
125 : "+m" (v->counter), "=qm" (c)
126 : : "memory");
127 return c != 0;
128}
129
130/**
131 * atomic_inc_and_test - increment and test
132 * @v: pointer of type atomic_t
133 *
134 * Atomically increments @v by 1
135 * and returns true if the result is zero, or false for all
136 * other cases.
137 */
138static inline int atomic_inc_and_test(atomic_t *v)
139{
140 unsigned char c;
141
142 asm volatile(LOCK_PREFIX "incl %0; sete %1"
143 : "+m" (v->counter), "=qm" (c)
144 : : "memory");
145 return c != 0;
146}
147
148/**
149 * atomic_add_negative - add and test if negative
150 * @v: pointer of type atomic_t
151 * @i: integer value to add
152 *
153 * Atomically adds @i to @v and returns true
154 * if the result is negative, or false when
155 * result is greater than or equal to zero.
156 */
157static inline int atomic_add_negative(int i, atomic_t *v)
158{
159 unsigned char c;
160
161 asm volatile(LOCK_PREFIX "addl %2,%0; sets %1"
162 : "+m" (v->counter), "=qm" (c)
163 : "ir" (i) : "memory");
164 return c;
165}
166
167/**
168 * atomic_add_return - add integer and return
169 * @v: pointer of type atomic_t
170 * @i: integer value to add
171 *
172 * Atomically adds @i to @v and returns @i + @v
173 */
174static inline int atomic_add_return(int i, atomic_t *v)
175{
176 int __i;
177#ifdef CONFIG_M386
178 unsigned long flags;
179 if (unlikely(boot_cpu_data.x86 <= 3))
180 goto no_xadd;
181#endif
182 /* Modern 486+ processor */
183 __i = i;
184 asm volatile(LOCK_PREFIX "xaddl %0, %1"
185 : "+r" (i), "+m" (v->counter)
186 : : "memory");
187 return i + __i;
188
189#ifdef CONFIG_M386
190no_xadd: /* Legacy 386 processor */
191 local_irq_save(flags);
192 __i = atomic_read(v);
193 atomic_set(v, i + __i);
194 local_irq_restore(flags);
195 return i + __i;
196#endif
197}
198
199/**
200 * atomic_sub_return - subtract integer and return
201 * @v: pointer of type atomic_t
202 * @i: integer value to subtract
203 *
204 * Atomically subtracts @i from @v and returns @v - @i
205 */
206static inline int atomic_sub_return(int i, atomic_t *v)
207{
208 return atomic_add_return(-i, v);
209}
210
211#define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), (old), (new)))
212#define atomic_xchg(v, new) (xchg(&((v)->counter), (new)))
213
214/**
215 * atomic_add_unless - add unless the number is already a given value
216 * @v: pointer of type atomic_t
217 * @a: the amount to add to v...
218 * @u: ...unless v is equal to u.
219 *
220 * Atomically adds @a to @v, so long as @v was not already @u.
221 * Returns non-zero if @v was not @u, and zero otherwise.
222 */
223static inline int atomic_add_unless(atomic_t *v, int a, int u)
224{
225 int c, old;
226 c = atomic_read(v);
227 for (;;) {
228 if (unlikely(c == (u)))
229 break;
230 old = atomic_cmpxchg((v), c, c + (a));
231 if (likely(old == c))
232 break;
233 c = old;
234 }
235 return c != (u);
236}
237
238#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
239
240#define atomic_inc_return(v) (atomic_add_return(1, v))
241#define atomic_dec_return(v) (atomic_sub_return(1, v))
242
243/* These are x86-specific, used by some header files */
244#define atomic_clear_mask(mask, addr) \
245 asm volatile(LOCK_PREFIX "andl %0,%1" \
246 : : "r" (~(mask)), "m" (*(addr)) : "memory")
247
248#define atomic_set_mask(mask, addr) \
249 asm volatile(LOCK_PREFIX "orl %0,%1" \
250 : : "r" (mask), "m" (*(addr)) : "memory")
251
252/* Atomic operations are already serializing on x86 */
253#define smp_mb__before_atomic_dec() barrier()
254#define smp_mb__after_atomic_dec() barrier()
255#define smp_mb__before_atomic_inc() barrier()
256#define smp_mb__after_atomic_inc() barrier()
257
258#include <asm-generic/atomic.h>
259#endif /* ASM_X86__ATOMIC_32_H */
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-24 19:18:51 -0500