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-rw-r--r--arch/sparc/include/asm/atomic_32.h104
1 files changed, 1 insertions, 103 deletions
diff --git a/arch/sparc/include/asm/atomic_32.h b/arch/sparc/include/asm/atomic_32.h
index 5c3c8b69884..9dd0a769fa1 100644
--- a/arch/sparc/include/asm/atomic_32.h
+++ b/arch/sparc/include/asm/atomic_32.h
@@ -13,7 +13,7 @@
13 13
14#include <linux/types.h> 14#include <linux/types.h>
15 15
16#ifdef __KERNEL__ 16#include <asm-generic/atomic64.h>
17 17
18#include <asm/system.h> 18#include <asm/system.h>
19 19
@@ -52,112 +52,10 @@ extern void atomic_set(atomic_t *, int);
52#define atomic_dec_and_test(v) (atomic_dec_return(v) == 0) 52#define atomic_dec_and_test(v) (atomic_dec_return(v) == 0)
53#define atomic_sub_and_test(i, v) (atomic_sub_return(i, v) == 0) 53#define atomic_sub_and_test(i, v) (atomic_sub_return(i, v) == 0)
54 54
55
56/* This is the old 24-bit implementation. It's still used internally
57 * by some sparc-specific code, notably the semaphore implementation.
58 */
59typedef struct { volatile int counter; } atomic24_t;
60
61#ifndef CONFIG_SMP
62
63#define ATOMIC24_INIT(i) { (i) }
64#define atomic24_read(v) ((v)->counter)
65#define atomic24_set(v, i) (((v)->counter) = i)
66
67#else
68/* We do the bulk of the actual work out of line in two common
69 * routines in assembler, see arch/sparc/lib/atomic.S for the
70 * "fun" details.
71 *
72 * For SMP the trick is you embed the spin lock byte within
73 * the word, use the low byte so signedness is easily retained
74 * via a quick arithmetic shift. It looks like this:
75 *
76 * ----------------------------------------
77 * | signed 24-bit counter value | lock | atomic_t
78 * ----------------------------------------
79 * 31 8 7 0
80 */
81
82#define ATOMIC24_INIT(i) { ((i) << 8) }
83
84static inline int atomic24_read(const atomic24_t *v)
85{
86 int ret = v->counter;
87
88 while(ret & 0xff)
89 ret = v->counter;
90
91 return ret >> 8;
92}
93
94#define atomic24_set(v, i) (((v)->counter) = ((i) << 8))
95#endif
96
97static inline int __atomic24_add(int i, atomic24_t *v)
98{
99 register volatile int *ptr asm("g1");
100 register int increment asm("g2");
101 register int tmp1 asm("g3");
102 register int tmp2 asm("g4");
103 register int tmp3 asm("g7");
104
105 ptr = &v->counter;
106 increment = i;
107
108 __asm__ __volatile__(
109 "mov %%o7, %%g4\n\t"
110 "call ___atomic24_add\n\t"
111 " add %%o7, 8, %%o7\n"
112 : "=&r" (increment), "=r" (tmp1), "=r" (tmp2), "=r" (tmp3)
113 : "0" (increment), "r" (ptr)
114 : "memory", "cc");
115
116 return increment;
117}
118
119static inline int __atomic24_sub(int i, atomic24_t *v)
120{
121 register volatile int *ptr asm("g1");
122 register int increment asm("g2");
123 register int tmp1 asm("g3");
124 register int tmp2 asm("g4");
125 register int tmp3 asm("g7");
126
127 ptr = &v->counter;
128 increment = i;
129
130 __asm__ __volatile__(
131 "mov %%o7, %%g4\n\t"
132 "call ___atomic24_sub\n\t"
133 " add %%o7, 8, %%o7\n"
134 : "=&r" (increment), "=r" (tmp1), "=r" (tmp2), "=r" (tmp3)
135 : "0" (increment), "r" (ptr)
136 : "memory", "cc");
137
138 return increment;
139}
140
141#define atomic24_add(i, v) ((void)__atomic24_add((i), (v)))
142#define atomic24_sub(i, v) ((void)__atomic24_sub((i), (v)))
143
144#define atomic24_dec_return(v) __atomic24_sub(1, (v))
145#define atomic24_inc_return(v) __atomic24_add(1, (v))
146
147#define atomic24_sub_and_test(i, v) (__atomic24_sub((i), (v)) == 0)
148#define atomic24_dec_and_test(v) (__atomic24_sub(1, (v)) == 0)
149
150#define atomic24_inc(v) ((void)__atomic24_add(1, (v)))
151#define atomic24_dec(v) ((void)__atomic24_sub(1, (v)))
152
153#define atomic24_add_negative(i, v) (__atomic24_add((i), (v)) < 0)
154
155/* Atomic operations are already serializing */ 55/* Atomic operations are already serializing */
156#define smp_mb__before_atomic_dec() barrier() 56#define smp_mb__before_atomic_dec() barrier()
157#define smp_mb__after_atomic_dec() barrier() 57#define smp_mb__after_atomic_dec() barrier()
158#define smp_mb__before_atomic_inc() barrier() 58#define smp_mb__before_atomic_inc() barrier()
159#define smp_mb__after_atomic_inc() barrier() 59#define smp_mb__after_atomic_inc() barrier()
160 60
161#endif /* !(__KERNEL__) */
162
163#endif /* !(__ARCH_SPARC_ATOMIC__) */ 61#endif /* !(__ARCH_SPARC_ATOMIC__) */