1 #ifndef _ASM_POWERPC_ATOMIC_H_
2 #define _ASM_POWERPC_ATOMIC_H_
5 * PowerPC atomic operations
8 typedef struct { volatile int counter; } atomic_t;
11 #include <asm/synch.h>
12 #include <asm/asm-compat.h>
14 #define ATOMIC_INIT(i) { (i) }
16 #define atomic_read(v) ((v)->counter)
17 #define atomic_set(v,i) (((v)->counter) = (i))
19 static __inline__ void atomic_add(int a, atomic_t *v)
24 "1: lwarx %0,0,%3 # atomic_add\n\
29 : "=&r" (t), "=m" (v->counter)
30 : "r" (a), "r" (&v->counter), "m" (v->counter)
34 static __inline__ int atomic_add_return(int a, atomic_t *v)
40 "1: lwarx %0,0,%2 # atomic_add_return\n\
47 : "r" (a), "r" (&v->counter)
53 #define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
55 static __inline__ void atomic_sub(int a, atomic_t *v)
60 "1: lwarx %0,0,%3 # atomic_sub\n\
65 : "=&r" (t), "=m" (v->counter)
66 : "r" (a), "r" (&v->counter), "m" (v->counter)
70 static __inline__ int atomic_sub_return(int a, atomic_t *v)
76 "1: lwarx %0,0,%2 # atomic_sub_return\n\
83 : "r" (a), "r" (&v->counter)
89 static __inline__ void atomic_inc(atomic_t *v)
94 "1: lwarx %0,0,%2 # atomic_inc\n\
99 : "=&r" (t), "=m" (v->counter)
100 : "r" (&v->counter), "m" (v->counter)
104 static __inline__ int atomic_inc_return(atomic_t *v)
108 __asm__ __volatile__(
110 "1: lwarx %0,0,%1 # atomic_inc_return\n\
124 * atomic_inc_and_test - increment and test
125 * @v: pointer of type atomic_t
127 * Atomically increments @v by 1
128 * and returns true if the result is zero, or false for all
131 #define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)
133 static __inline__ void atomic_dec(atomic_t *v)
137 __asm__ __volatile__(
138 "1: lwarx %0,0,%2 # atomic_dec\n\
143 : "=&r" (t), "=m" (v->counter)
144 : "r" (&v->counter), "m" (v->counter)
148 static __inline__ int atomic_dec_return(atomic_t *v)
152 __asm__ __volatile__(
154 "1: lwarx %0,0,%1 # atomic_dec_return\n\
167 #define atomic_sub_and_test(a, v) (atomic_sub_return((a), (v)) == 0)
168 #define atomic_dec_and_test(v) (atomic_dec_return((v)) == 0)
171 * Atomically test *v and decrement if it is greater than 0.
172 * The function returns the old value of *v minus 1.
174 static __inline__ int atomic_dec_if_positive(atomic_t *v)
178 __asm__ __volatile__(
180 "1: lwarx %0,0,%1 # atomic_dec_if_positive\n\
195 #define smp_mb__before_atomic_dec() smp_mb()
196 #define smp_mb__after_atomic_dec() smp_mb()
197 #define smp_mb__before_atomic_inc() smp_mb()
198 #define smp_mb__after_atomic_inc() smp_mb()
200 #endif /* __KERNEL__ */
201 #endif /* _ASM_POWERPC_ATOMIC_H_ */