tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Copyright (C) 2006 Atmark Techno, Inc.
3 *
4 * This file is subject to the terms and conditions of the GNU General Public
5 * License. See the file "COPYING" in the main directory of this archive
6 * for more details.
7 */
8
9#ifndef _ASM_MICROBLAZE_ATOMIC_H
10#define _ASM_MICROBLAZE_ATOMIC_H
11
12#include <linux/types.h>
13#include <linux/compiler.h> /* likely */
14#include <asm/system.h> /* local_irq_XXX and friends */
15
16#define ATOMIC_INIT(i) { (i) }
17#define atomic_read(v) ((v)->counter)
18#define atomic_set(v, i) (((v)->counter) = (i))
19
20#define atomic_inc(v) (atomic_add_return(1, (v)))
21#define atomic_dec(v) (atomic_sub_return(1, (v)))
22
23#define atomic_add(i, v) (atomic_add_return(i, (v)))
24#define atomic_sub(i, v) (atomic_sub_return(i, (v)))
25
26#define atomic_inc_return(v) (atomic_add_return(1, (v)))
27#define atomic_dec_return(v) (atomic_sub_return(1, (v)))
28
29#define atomic_inc_and_test(v) (atomic_add_return(1, (v)) == 0)
30#define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0)
31
32#define atomic_inc_not_zero(v) (atomic_add_unless((v), 1, 0))
33
34#define atomic_sub_and_test(i, v) (atomic_sub_return((i), (v)) == 0)
35
36static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
37{
38 int ret;
39 unsigned long flags;
40
41 local_irq_save(flags);
42 ret = v->counter;
43 if (likely(ret == old))
44 v->counter = new;
45 local_irq_restore(flags);
46
47 return ret;
48}
49
50static inline int atomic_add_unless(atomic_t *v, int a, int u)
51{
52 int c, old;
53
54 c = atomic_read(v);
55 while (c != u && (old = atomic_cmpxchg((v), c, c + a)) != c)
56 c = old;
57 return c != u;
58}
59
60static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr)
61{
62 unsigned long flags;
63
64 local_irq_save(flags);
65 *addr &= ~mask;
66 local_irq_restore(flags);
67}
68
69/**
70 * atomic_add_return - add and return
71 * @i: integer value to add
72 * @v: pointer of type atomic_t
73 *
74 * Atomically adds @i to @v and returns @i + @v
75 */
76static inline int atomic_add_return(int i, atomic_t *v)
77{
78 unsigned long flags;
79 int val;
80
81 local_irq_save(flags);
82 val = v->counter;
83 v->counter = val += i;
84 local_irq_restore(flags);
85
86 return val;
87}
88
89static inline int atomic_sub_return(int i, atomic_t *v)
90{
91 return atomic_add_return(-i, v);
92}
93
94/*
95 * Atomically test *v and decrement if it is greater than 0.
96 * The function returns the old value of *v minus 1.
97 */
98static inline int atomic_dec_if_positive(atomic_t *v)
99{
100 unsigned long flags;
101 int res;
102
103 local_irq_save(flags);
104 res = v->counter - 1;
105 if (res >= 0)
106 v->counter = res;
107 local_irq_restore(flags);
108
109 return res;
110}
111
112#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
113#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
114
115/* Atomic operations are already serializing */
116#define smp_mb__before_atomic_dec() barrier()
117#define smp_mb__after_atomic_dec() barrier()
118#define smp_mb__before_atomic_inc() barrier()
119#define smp_mb__after_atomic_inc() barrier()
120
121#include <asm-generic/atomic.h>
122
123#endif /* _ASM_MICROBLAZE_ATOMIC_H */