#ifndef __ASM_SH_ATOMIC_H #define __ASM_SH_ATOMIC_H /* * Atomic operations that C can't guarantee us. Useful for * resource counting etc.. * */ #include <linux/compiler.h> #include <linux/types.h> #include <asm/cmpxchg.h> #include <asm/barrier.h> #define ATOMIC_INIT(i) { (i) } #define atomic_read(v) ACCESS_ONCE((v)->counter) #define atomic_set(v,i) ((v)->counter = (i)) #if defined(CONFIG_GUSA_RB) #include <asm/atomic-grb.h> #elif defined(CONFIG_CPU_SH4A) #include <asm/atomic-llsc.h> #else #include <asm/atomic-irq.h> #endif #define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0) #define atomic_dec_return(v) atomic_sub_return(1, (v)) #define atomic_inc_return(v) atomic_add_return(1, (v)) #define atomic_inc_and_test(v) (atomic_inc_return(v) == 0) #define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0) #define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0) #define atomic_inc(v) atomic_add(1, (v)) #define atomic_dec(v) atomic_sub(1, (v)) #define atomic_xchg(v, new) (xchg(&((v)->counter), new)) #define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n))) /** * __atomic_add_unless - add unless the number is a given value * @v: pointer of type atomic_t * @a: the amount to add to v... * @u: ...unless v is equal to u. * * Atomically adds @a to @v, so long as it was not @u. * Returns the old value of @v. */ static inline int __atomic_add_unless(atomic_t *v, int a, int u) { int c, old; c = atomic_read(v); for (;;) { if (unlikely(c == (u))) break; old = atomic_cmpxchg((v), c, c + (a)); if (likely(old == c)) break; c = old; } return c; } #endif /* __ASM_SH_ATOMIC_H */