#ifndef __ARCH_I386_ATOMIC__ #define __ARCH_I386_ATOMIC__ /* * Atomic operations that C can't guarantee us. Useful for * resource counting etc.. */ #ifdef __SMP__ #define LOCK "lock ; " #else #define LOCK "" #endif /* * Make sure gcc doesn't try to be clever and move things around * on us. We need to use _exactly_ the address the user gave us, * not some alias that contains the same information. */ #define __atomic_fool_gcc(x) (*(struct { int a[100]; } *)x) typedef int atomic_t; #define atomic_read(v) (*v) static __inline__ void atomic_add(atomic_t i, atomic_t *v) { __asm__ __volatile__( LOCK "addl %1,%0" :"=m" (__atomic_fool_gcc(v)) :"ir" (i), "m" (__atomic_fool_gcc(v))); } static __inline__ void atomic_sub(atomic_t i, atomic_t *v) { __asm__ __volatile__( LOCK "subl %1,%0" :"=m" (__atomic_fool_gcc(v)) :"ir" (i), "m" (__atomic_fool_gcc(v))); } static __inline__ void atomic_inc(atomic_t *v) { __asm__ __volatile__( LOCK "incl %0" :"=m" (__atomic_fool_gcc(v)) :"m" (__atomic_fool_gcc(v))); } static __inline__ void atomic_dec(atomic_t *v) { __asm__ __volatile__( LOCK "decl %0" :"=m" (__atomic_fool_gcc(v)) :"m" (__atomic_fool_gcc(v))); } static __inline__ int atomic_dec_and_test(atomic_t *v) { unsigned char c; __asm__ __volatile__( LOCK "decl %0; sete %1" :"=m" (__atomic_fool_gcc(v)), "=qm" (c) :"m" (__atomic_fool_gcc(v))); return c != 0; } #endif