diff options
Diffstat (limited to 'include/asm-x86/local_32.h')
-rw-r--r-- | include/asm-x86/local_32.h | 233 |
1 files changed, 233 insertions, 0 deletions
diff --git a/include/asm-x86/local_32.h b/include/asm-x86/local_32.h new file mode 100644 index 000000000000..6e85975b9ed2 --- /dev/null +++ b/include/asm-x86/local_32.h | |||
@@ -0,0 +1,233 @@ | |||
1 | #ifndef _ARCH_I386_LOCAL_H | ||
2 | #define _ARCH_I386_LOCAL_H | ||
3 | |||
4 | #include <linux/percpu.h> | ||
5 | #include <asm/system.h> | ||
6 | #include <asm/atomic.h> | ||
7 | |||
8 | typedef struct | ||
9 | { | ||
10 | atomic_long_t a; | ||
11 | } local_t; | ||
12 | |||
13 | #define LOCAL_INIT(i) { ATOMIC_LONG_INIT(i) } | ||
14 | |||
15 | #define local_read(l) atomic_long_read(&(l)->a) | ||
16 | #define local_set(l,i) atomic_long_set(&(l)->a, (i)) | ||
17 | |||
18 | static __inline__ void local_inc(local_t *l) | ||
19 | { | ||
20 | __asm__ __volatile__( | ||
21 | "incl %0" | ||
22 | :"+m" (l->a.counter)); | ||
23 | } | ||
24 | |||
25 | static __inline__ void local_dec(local_t *l) | ||
26 | { | ||
27 | __asm__ __volatile__( | ||
28 | "decl %0" | ||
29 | :"+m" (l->a.counter)); | ||
30 | } | ||
31 | |||
32 | static __inline__ void local_add(long i, local_t *l) | ||
33 | { | ||
34 | __asm__ __volatile__( | ||
35 | "addl %1,%0" | ||
36 | :"+m" (l->a.counter) | ||
37 | :"ir" (i)); | ||
38 | } | ||
39 | |||
40 | static __inline__ void local_sub(long i, local_t *l) | ||
41 | { | ||
42 | __asm__ __volatile__( | ||
43 | "subl %1,%0" | ||
44 | :"+m" (l->a.counter) | ||
45 | :"ir" (i)); | ||
46 | } | ||
47 | |||
48 | /** | ||
49 | * local_sub_and_test - subtract value from variable and test result | ||
50 | * @i: integer value to subtract | ||
51 | * @l: pointer of type local_t | ||
52 | * | ||
53 | * Atomically subtracts @i from @l and returns | ||
54 | * true if the result is zero, or false for all | ||
55 | * other cases. | ||
56 | */ | ||
57 | static __inline__ int local_sub_and_test(long i, local_t *l) | ||
58 | { | ||
59 | unsigned char c; | ||
60 | |||
61 | __asm__ __volatile__( | ||
62 | "subl %2,%0; sete %1" | ||
63 | :"+m" (l->a.counter), "=qm" (c) | ||
64 | :"ir" (i) : "memory"); | ||
65 | return c; | ||
66 | } | ||
67 | |||
68 | /** | ||
69 | * local_dec_and_test - decrement and test | ||
70 | * @l: pointer of type local_t | ||
71 | * | ||
72 | * Atomically decrements @l by 1 and | ||
73 | * returns true if the result is 0, or false for all other | ||
74 | * cases. | ||
75 | */ | ||
76 | static __inline__ int local_dec_and_test(local_t *l) | ||
77 | { | ||
78 | unsigned char c; | ||
79 | |||
80 | __asm__ __volatile__( | ||
81 | "decl %0; sete %1" | ||
82 | :"+m" (l->a.counter), "=qm" (c) | ||
83 | : : "memory"); | ||
84 | return c != 0; | ||
85 | } | ||
86 | |||
87 | /** | ||
88 | * local_inc_and_test - increment and test | ||
89 | * @l: pointer of type local_t | ||
90 | * | ||
91 | * Atomically increments @l by 1 | ||
92 | * and returns true if the result is zero, or false for all | ||
93 | * other cases. | ||
94 | */ | ||
95 | static __inline__ int local_inc_and_test(local_t *l) | ||
96 | { | ||
97 | unsigned char c; | ||
98 | |||
99 | __asm__ __volatile__( | ||
100 | "incl %0; sete %1" | ||
101 | :"+m" (l->a.counter), "=qm" (c) | ||
102 | : : "memory"); | ||
103 | return c != 0; | ||
104 | } | ||
105 | |||
106 | /** | ||
107 | * local_add_negative - add and test if negative | ||
108 | * @l: pointer of type local_t | ||
109 | * @i: integer value to add | ||
110 | * | ||
111 | * Atomically adds @i to @l and returns true | ||
112 | * if the result is negative, or false when | ||
113 | * result is greater than or equal to zero. | ||
114 | */ | ||
115 | static __inline__ int local_add_negative(long i, local_t *l) | ||
116 | { | ||
117 | unsigned char c; | ||
118 | |||
119 | __asm__ __volatile__( | ||
120 | "addl %2,%0; sets %1" | ||
121 | :"+m" (l->a.counter), "=qm" (c) | ||
122 | :"ir" (i) : "memory"); | ||
123 | return c; | ||
124 | } | ||
125 | |||
126 | /** | ||
127 | * local_add_return - add and return | ||
128 | * @l: pointer of type local_t | ||
129 | * @i: integer value to add | ||
130 | * | ||
131 | * Atomically adds @i to @l and returns @i + @l | ||
132 | */ | ||
133 | static __inline__ long local_add_return(long i, local_t *l) | ||
134 | { | ||
135 | long __i; | ||
136 | #ifdef CONFIG_M386 | ||
137 | unsigned long flags; | ||
138 | if(unlikely(boot_cpu_data.x86 <= 3)) | ||
139 | goto no_xadd; | ||
140 | #endif | ||
141 | /* Modern 486+ processor */ | ||
142 | __i = i; | ||
143 | __asm__ __volatile__( | ||
144 | "xaddl %0, %1;" | ||
145 | :"+r" (i), "+m" (l->a.counter) | ||
146 | : : "memory"); | ||
147 | return i + __i; | ||
148 | |||
149 | #ifdef CONFIG_M386 | ||
150 | no_xadd: /* Legacy 386 processor */ | ||
151 | local_irq_save(flags); | ||
152 | __i = local_read(l); | ||
153 | local_set(l, i + __i); | ||
154 | local_irq_restore(flags); | ||
155 | return i + __i; | ||
156 | #endif | ||
157 | } | ||
158 | |||
159 | static __inline__ long local_sub_return(long i, local_t *l) | ||
160 | { | ||
161 | return local_add_return(-i,l); | ||
162 | } | ||
163 | |||
164 | #define local_inc_return(l) (local_add_return(1,l)) | ||
165 | #define local_dec_return(l) (local_sub_return(1,l)) | ||
166 | |||
167 | #define local_cmpxchg(l, o, n) \ | ||
168 | (cmpxchg_local(&((l)->a.counter), (o), (n))) | ||
169 | /* Always has a lock prefix */ | ||
170 | #define local_xchg(l, n) (xchg(&((l)->a.counter), (n))) | ||
171 | |||
172 | /** | ||
173 | * local_add_unless - add unless the number is a given value | ||
174 | * @l: pointer of type local_t | ||
175 | * @a: the amount to add to l... | ||
176 | * @u: ...unless l is equal to u. | ||
177 | * | ||
178 | * Atomically adds @a to @l, so long as it was not @u. | ||
179 | * Returns non-zero if @l was not @u, and zero otherwise. | ||
180 | */ | ||
181 | #define local_add_unless(l, a, u) \ | ||
182 | ({ \ | ||
183 | long c, old; \ | ||
184 | c = local_read(l); \ | ||
185 | for (;;) { \ | ||
186 | if (unlikely(c == (u))) \ | ||
187 | break; \ | ||
188 | old = local_cmpxchg((l), c, c + (a)); \ | ||
189 | if (likely(old == c)) \ | ||
190 | break; \ | ||
191 | c = old; \ | ||
192 | } \ | ||
193 | c != (u); \ | ||
194 | }) | ||
195 | #define local_inc_not_zero(l) local_add_unless((l), 1, 0) | ||
196 | |||
197 | /* On x86, these are no better than the atomic variants. */ | ||
198 | #define __local_inc(l) local_inc(l) | ||
199 | #define __local_dec(l) local_dec(l) | ||
200 | #define __local_add(i,l) local_add((i),(l)) | ||
201 | #define __local_sub(i,l) local_sub((i),(l)) | ||
202 | |||
203 | /* Use these for per-cpu local_t variables: on some archs they are | ||
204 | * much more efficient than these naive implementations. Note they take | ||
205 | * a variable, not an address. | ||
206 | */ | ||
207 | |||
208 | /* Need to disable preemption for the cpu local counters otherwise we could | ||
209 | still access a variable of a previous CPU in a non atomic way. */ | ||
210 | #define cpu_local_wrap_v(l) \ | ||
211 | ({ local_t res__; \ | ||
212 | preempt_disable(); \ | ||
213 | res__ = (l); \ | ||
214 | preempt_enable(); \ | ||
215 | res__; }) | ||
216 | #define cpu_local_wrap(l) \ | ||
217 | ({ preempt_disable(); \ | ||
218 | l; \ | ||
219 | preempt_enable(); }) \ | ||
220 | |||
221 | #define cpu_local_read(l) cpu_local_wrap_v(local_read(&__get_cpu_var(l))) | ||
222 | #define cpu_local_set(l, i) cpu_local_wrap(local_set(&__get_cpu_var(l), (i))) | ||
223 | #define cpu_local_inc(l) cpu_local_wrap(local_inc(&__get_cpu_var(l))) | ||
224 | #define cpu_local_dec(l) cpu_local_wrap(local_dec(&__get_cpu_var(l))) | ||
225 | #define cpu_local_add(i, l) cpu_local_wrap(local_add((i), &__get_cpu_var(l))) | ||
226 | #define cpu_local_sub(i, l) cpu_local_wrap(local_sub((i), &__get_cpu_var(l))) | ||
227 | |||
228 | #define __cpu_local_inc(l) cpu_local_inc(l) | ||
229 | #define __cpu_local_dec(l) cpu_local_dec(l) | ||
230 | #define __cpu_local_add(i, l) cpu_local_add((i), (l)) | ||
231 | #define __cpu_local_sub(i, l) cpu_local_sub((i), (l)) | ||
232 | |||
233 | #endif /* _ARCH_I386_LOCAL_H */ | ||