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authorHarvey Harrison <harvey.harrison@gmail.com>2008-01-30 07:31:26 -0500
committerIngo Molnar <mingo@elte.hu>2008-01-30 07:31:26 -0500
commit5638f99394d478bcba6384ac7c51e763d1a3a448 (patch)
tree7edf6a96ed26ef8cde23cad655f76299f93874c9 /include/asm-x86/local.h
parent8ee5797a91bdb713b4031741b33bd035f9c43870 (diff)
x86: unify local_{32|64}.h
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'include/asm-x86/local.h')
-rw-r--r--include/asm-x86/local.h244
1 files changed, 240 insertions, 4 deletions
diff --git a/include/asm-x86/local.h b/include/asm-x86/local.h
index c7a1b1c66c96..f5677e208601 100644
--- a/include/asm-x86/local.h
+++ b/include/asm-x86/local.h
@@ -1,5 +1,241 @@
1#ifdef CONFIG_X86_32 1#ifndef _ARCH_LOCAL_H
2# include "local_32.h" 2#define _ARCH_LOCAL_H
3#else 3
4# include "local_64.h" 4#include <linux/percpu.h>
5
6#include <asm/system.h>
7#include <asm/atomic.h>
8#include <asm/asm.h>
9
10typedef struct
11{
12 atomic_long_t a;
13} local_t;
14
15#define LOCAL_INIT(i) { ATOMIC_LONG_INIT(i) }
16
17#define local_read(l) atomic_long_read(&(l)->a)
18#define local_set(l,i) atomic_long_set(&(l)->a, (i))
19
20static inline void local_inc(local_t *l)
21{
22 __asm__ __volatile__(
23 _ASM_INC "%0"
24 :"+m" (l->a.counter));
25}
26
27static inline void local_dec(local_t *l)
28{
29 __asm__ __volatile__(
30 _ASM_DEC "%0"
31 :"+m" (l->a.counter));
32}
33
34static inline void local_add(long i, local_t *l)
35{
36 __asm__ __volatile__(
37 _ASM_ADD "%1,%0"
38 :"+m" (l->a.counter)
39 :"ir" (i));
40}
41
42static inline void local_sub(long i, local_t *l)
43{
44 __asm__ __volatile__(
45 _ASM_SUB "%1,%0"
46 :"+m" (l->a.counter)
47 :"ir" (i));
48}
49
50/**
51 * local_sub_and_test - subtract value from variable and test result
52 * @i: integer value to subtract
53 * @l: pointer to type local_t
54 *
55 * Atomically subtracts @i from @l and returns
56 * true if the result is zero, or false for all
57 * other cases.
58 */
59static inline int local_sub_and_test(long i, local_t *l)
60{
61 unsigned char c;
62
63 __asm__ __volatile__(
64 _ASM_SUB "%2,%0; sete %1"
65 :"+m" (l->a.counter), "=qm" (c)
66 :"ir" (i) : "memory");
67 return c;
68}
69
70/**
71 * local_dec_and_test - decrement and test
72 * @l: pointer to type local_t
73 *
74 * Atomically decrements @l by 1 and
75 * returns true if the result is 0, or false for all other
76 * cases.
77 */
78static inline int local_dec_and_test(local_t *l)
79{
80 unsigned char c;
81
82 __asm__ __volatile__(
83 _ASM_DEC "%0; sete %1"
84 :"+m" (l->a.counter), "=qm" (c)
85 : : "memory");
86 return c != 0;
87}
88
89/**
90 * local_inc_and_test - increment and test
91 * @l: pointer to type local_t
92 *
93 * Atomically increments @l by 1
94 * and returns true if the result is zero, or false for all
95 * other cases.
96 */
97static inline int local_inc_and_test(local_t *l)
98{
99 unsigned char c;
100
101 __asm__ __volatile__(
102 _ASM_INC "%0; sete %1"
103 :"+m" (l->a.counter), "=qm" (c)
104 : : "memory");
105 return c != 0;
106}
107
108/**
109 * local_add_negative - add and test if negative
110 * @i: integer value to add
111 * @l: pointer to type local_t
112 *
113 * Atomically adds @i to @l and returns true
114 * if the result is negative, or false when
115 * result is greater than or equal to zero.
116 */
117static inline int local_add_negative(long i, local_t *l)
118{
119 unsigned char c;
120
121 __asm__ __volatile__(
122 _ASM_ADD "%2,%0; sets %1"
123 :"+m" (l->a.counter), "=qm" (c)
124 :"ir" (i) : "memory");
125 return c;
126}
127
128/**
129 * local_add_return - add and return
130 * @i: integer value to add
131 * @l: pointer to type local_t
132 *
133 * Atomically adds @i to @l and returns @i + @l
134 */
135static inline long local_add_return(long i, local_t *l)
136{
137 long __i;
138#ifdef CONFIG_M386
139 unsigned long flags;
140 if(unlikely(boot_cpu_data.x86 <= 3))
141 goto no_xadd;
5#endif 142#endif
143 /* Modern 486+ processor */
144 __i = i;
145 __asm__ __volatile__(
146 _ASM_XADD "%0, %1;"
147 :"+r" (i), "+m" (l->a.counter)
148 : : "memory");
149 return i + __i;
150
151#ifdef CONFIG_M386
152no_xadd: /* Legacy 386 processor */
153 local_irq_save(flags);
154 __i = local_read(l);
155 local_set(l, i + __i);
156 local_irq_restore(flags);
157 return i + __i;
158#endif
159}
160
161static inline long local_sub_return(long i, local_t *l)
162{
163 return local_add_return(-i,l);
164}
165
166#define local_inc_return(l) (local_add_return(1,l))
167#define local_dec_return(l) (local_sub_return(1,l))
168
169#define local_cmpxchg(l, o, n) \
170 (cmpxchg_local(&((l)->a.counter), (o), (n)))
171/* Always has a lock prefix */
172#define local_xchg(l, n) (xchg(&((l)->a.counter), (n)))
173
174/**
175 * local_add_unless - add unless the number is a given value
176 * @l: pointer of type local_t
177 * @a: the amount to add to l...
178 * @u: ...unless l is equal to u.
179 *
180 * Atomically adds @a to @l, so long as it was not @u.
181 * Returns non-zero if @l was not @u, and zero otherwise.
182 */
183#define local_add_unless(l, a, u) \
184({ \
185 long c, old; \
186 c = local_read(l); \
187 for (;;) { \
188 if (unlikely(c == (u))) \
189 break; \
190 old = local_cmpxchg((l), c, c + (a)); \
191 if (likely(old == c)) \
192 break; \
193 c = old; \
194 } \
195 c != (u); \
196})
197#define local_inc_not_zero(l) local_add_unless((l), 1, 0)
198
199/* On x86_32, these are no better than the atomic variants.
200 * On x86-64 these are better than the atomic variants on SMP kernels
201 * because they dont use a lock prefix.
202 */
203#define __local_inc(l) local_inc(l)
204#define __local_dec(l) local_dec(l)
205#define __local_add(i,l) local_add((i),(l))
206#define __local_sub(i,l) local_sub((i),(l))
207
208/* Use these for per-cpu local_t variables: on some archs they are
209 * much more efficient than these naive implementations. Note they take
210 * a variable, not an address.
211 *
212 * X86_64: This could be done better if we moved the per cpu data directly
213 * after GS.
214 */
215
216/* Need to disable preemption for the cpu local counters otherwise we could
217 still access a variable of a previous CPU in a non atomic way. */
218#define cpu_local_wrap_v(l) \
219 ({ local_t res__; \
220 preempt_disable(); \
221 res__ = (l); \
222 preempt_enable(); \
223 res__; })
224#define cpu_local_wrap(l) \
225 ({ preempt_disable(); \
226 l; \
227 preempt_enable(); }) \
228
229#define cpu_local_read(l) cpu_local_wrap_v(local_read(&__get_cpu_var(l)))
230#define cpu_local_set(l, i) cpu_local_wrap(local_set(&__get_cpu_var(l), (i)))
231#define cpu_local_inc(l) cpu_local_wrap(local_inc(&__get_cpu_var(l)))
232#define cpu_local_dec(l) cpu_local_wrap(local_dec(&__get_cpu_var(l)))
233#define cpu_local_add(i, l) cpu_local_wrap(local_add((i), &__get_cpu_var(l)))
234#define cpu_local_sub(i, l) cpu_local_wrap(local_sub((i), &__get_cpu_var(l)))
235
236#define __cpu_local_inc(l) cpu_local_inc(l)
237#define __cpu_local_dec(l) cpu_local_dec(l)
238#define __cpu_local_add(i, l) cpu_local_add((i), (l))
239#define __cpu_local_sub(i, l) cpu_local_sub((i), (l))
240
241#endif /* _ARCH_LOCAL_H */