diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-sh/atomic.h |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'include/asm-sh/atomic.h')
-rw-r--r-- | include/asm-sh/atomic.h | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/include/asm-sh/atomic.h b/include/asm-sh/atomic.h new file mode 100644 index 000000000000..3c4f805da1ac --- /dev/null +++ b/include/asm-sh/atomic.h | |||
@@ -0,0 +1,114 @@ | |||
1 | #ifndef __ASM_SH_ATOMIC_H | ||
2 | #define __ASM_SH_ATOMIC_H | ||
3 | |||
4 | /* | ||
5 | * Atomic operations that C can't guarantee us. Useful for | ||
6 | * resource counting etc.. | ||
7 | * | ||
8 | */ | ||
9 | |||
10 | typedef struct { volatile int counter; } atomic_t; | ||
11 | |||
12 | #define ATOMIC_INIT(i) ( (atomic_t) { (i) } ) | ||
13 | |||
14 | #define atomic_read(v) ((v)->counter) | ||
15 | #define atomic_set(v,i) ((v)->counter = (i)) | ||
16 | |||
17 | #include <asm/system.h> | ||
18 | |||
19 | /* | ||
20 | * To get proper branch prediction for the main line, we must branch | ||
21 | * forward to code at the end of this object's .text section, then | ||
22 | * branch back to restart the operation. | ||
23 | */ | ||
24 | |||
25 | static __inline__ void atomic_add(int i, atomic_t * v) | ||
26 | { | ||
27 | unsigned long flags; | ||
28 | |||
29 | local_irq_save(flags); | ||
30 | *(long *)v += i; | ||
31 | local_irq_restore(flags); | ||
32 | } | ||
33 | |||
34 | static __inline__ void atomic_sub(int i, atomic_t *v) | ||
35 | { | ||
36 | unsigned long flags; | ||
37 | |||
38 | local_irq_save(flags); | ||
39 | *(long *)v -= i; | ||
40 | local_irq_restore(flags); | ||
41 | } | ||
42 | |||
43 | static __inline__ int atomic_add_return(int i, atomic_t * v) | ||
44 | { | ||
45 | unsigned long temp, flags; | ||
46 | |||
47 | local_irq_save(flags); | ||
48 | temp = *(long *)v; | ||
49 | temp += i; | ||
50 | *(long *)v = temp; | ||
51 | local_irq_restore(flags); | ||
52 | |||
53 | return temp; | ||
54 | } | ||
55 | |||
56 | #define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0) | ||
57 | |||
58 | static __inline__ int atomic_sub_return(int i, atomic_t * v) | ||
59 | { | ||
60 | unsigned long temp, flags; | ||
61 | |||
62 | local_irq_save(flags); | ||
63 | temp = *(long *)v; | ||
64 | temp -= i; | ||
65 | *(long *)v = temp; | ||
66 | local_irq_restore(flags); | ||
67 | |||
68 | return temp; | ||
69 | } | ||
70 | |||
71 | #define atomic_dec_return(v) atomic_sub_return(1,(v)) | ||
72 | #define atomic_inc_return(v) atomic_add_return(1,(v)) | ||
73 | |||
74 | /* | ||
75 | * atomic_inc_and_test - increment and test | ||
76 | * @v: pointer of type atomic_t | ||
77 | * | ||
78 | * Atomically increments @v by 1 | ||
79 | * and returns true if the result is zero, or false for all | ||
80 | * other cases. | ||
81 | */ | ||
82 | #define atomic_inc_and_test(v) (atomic_inc_return(v) == 0) | ||
83 | |||
84 | #define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0) | ||
85 | #define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0) | ||
86 | |||
87 | #define atomic_inc(v) atomic_add(1,(v)) | ||
88 | #define atomic_dec(v) atomic_sub(1,(v)) | ||
89 | |||
90 | static __inline__ void atomic_clear_mask(unsigned int mask, atomic_t *v) | ||
91 | { | ||
92 | unsigned long flags; | ||
93 | |||
94 | local_irq_save(flags); | ||
95 | *(long *)v &= ~mask; | ||
96 | local_irq_restore(flags); | ||
97 | } | ||
98 | |||
99 | static __inline__ void atomic_set_mask(unsigned int mask, atomic_t *v) | ||
100 | { | ||
101 | unsigned long flags; | ||
102 | |||
103 | local_irq_save(flags); | ||
104 | *(long *)v |= mask; | ||
105 | local_irq_restore(flags); | ||
106 | } | ||
107 | |||
108 | /* Atomic operations are already serializing on SH */ | ||
109 | #define smp_mb__before_atomic_dec() barrier() | ||
110 | #define smp_mb__after_atomic_dec() barrier() | ||
111 | #define smp_mb__before_atomic_inc() barrier() | ||
112 | #define smp_mb__after_atomic_inc() barrier() | ||
113 | |||
114 | #endif /* __ASM_SH_ATOMIC_H */ | ||