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#include <linux/compiler.h> 11#include <linux/types.h> 12#include <asm/system.h> 13 14#define ATOMIC_INIT(i) ( (atomic_t) { (i) } ) 15 16#define atomic_read(v) (*(volatile int *)&(v)->counter) 17#define atomic_set(v,i) ((v)->counter = (i)) 18 19#if defined(CONFIG_GUSA_RB) 20#include <asm/atomic-grb.h> 21#elif defined(CONFIG_CPU_SH4A) 22#include <asm/atomic-llsc.h> 23#else 24#include <asm/atomic-irq.h> 25#endif 26 27#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0) 28#define atomic_dec_return(v) atomic_sub_return(1, (v)) 29#define atomic_inc_return(v) atomic_add_return(1, (v)) 30#define atomic_inc_and_test(v) (atomic_inc_return(v) == 0) 31#define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0) 32#define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0) 33#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0) 34 35#define atomic_inc(v) atomic_add(1, (v)) 36#define atomic_dec(v) atomic_sub(1, (v)) 37 38#define atomic_xchg(v, new) (xchg(&((v)->counter), new)) 39#define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n))) 40 41/** 42 * atomic_add_unless - add unless the number is a given value 43 * @v: pointer of type atomic_t 44 * @a: the amount to add to v... 45 * @u: ...unless v is equal to u. 46 * 47 * Atomically adds @a to @v, so long as it was not @u. 48 * Returns non-zero if @v was not @u, and zero otherwise. 49 */ 50static inline int atomic_add_unless(atomic_t *v, int a, int u) 51{ 52 int c, old; 53 c = atomic_read(v); 54 for (;;) { 55 if (unlikely(c == (u))) 56 break; 57 old = atomic_cmpxchg((v), c, c + (a)); 58 if (likely(old == c)) 59 break; 60 c = old; 61 } 62 63 return c != (u); 64} 65 66#define smp_mb__before_atomic_dec() smp_mb() 67#define smp_mb__after_atomic_dec() smp_mb() 68#define smp_mb__before_atomic_inc() smp_mb() 69#define smp_mb__after_atomic_inc() smp_mb() 70 71#include <asm-generic/atomic-long.h> 72#include <asm-generic/atomic64.h> 73 74#endif /* __ASM_SH_ATOMIC_H */ 75