Subversion Repositories or1k

#ifndef __ARCH_ALPHA_ATOMIC__

#define __ARCH_ALPHA_ATOMIC__

/*

 * Atomic operations that C can't guarantee us.  Useful for

 * resource counting etc...

 *

 * But use these as seldom as possible since they are much more slower

 * than regular operations.

 */

/*

 * 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;

extern __inline__ void atomic_add(atomic_t i, atomic_t * v)

{

        unsigned long temp;

        __asm__ __volatile__(

                "\n1:\t"

                "ldl_l %0,%1\n\t"

                "addl %0,%2,%0\n\t"

                "stl_c %0,%1\n\t"

                "beq %0,1b\n"

                "2:"

                :"=&r" (temp),

                 "=m" (__atomic_fool_gcc(v))

                :"Ir" (i),

                 "m" (__atomic_fool_gcc(v)));

}

extern __inline__ void atomic_sub(atomic_t i, atomic_t * v)

{

        unsigned long temp;

        __asm__ __volatile__(

                "\n1:\t"

                "ldl_l %0,%1\n\t"

                "subl %0,%2,%0\n\t"

                "stl_c %0,%1\n\t"

                "beq %0,1b\n"

                "2:"

                :"=&r" (temp),

                 "=m" (__atomic_fool_gcc(v))

                :"Ir" (i),

                 "m" (__atomic_fool_gcc(v)));

}

/*

 * Same as above, but return the result value

 */

extern __inline__ long atomic_add_return(atomic_t i, atomic_t * v)

{

        long temp, result;

        __asm__ __volatile__(

                "\n1:\t"

                "ldl_l %0,%1\n\t"

                "addl %0,%3,%0\n\t"

                "bis %0,%0,%2\n\t"

                "stl_c %0,%1\n\t"

                "beq %0,1b\n"

                "2:"

                :"=&r" (temp),

                 "=m" (__atomic_fool_gcc(v)),

                 "=&r" (result)

                :"Ir" (i),

                 "m" (__atomic_fool_gcc(v)));

        return result;

}

extern __inline__ long atomic_sub_return(atomic_t i, atomic_t * v)

{

        long temp, result;

        __asm__ __volatile__(

                "\n1:\t"

                "ldl_l %0,%1\n\t"

                "subl %0,%3,%0\n\t"

                "bis %0,%0,%2\n\t"

                "stl_c %0,%1\n\t"

                "beq %0,1b\n"

                "2:"

                :"=&r" (temp),

                 "=m" (__atomic_fool_gcc(v)),

                 "=&r" (result)

                :"Ir" (i),

                 "m" (__atomic_fool_gcc(v)));

        return result;

}

#define atomic_dec_return(v) atomic_sub_return(1,(v))

#define atomic_inc_return(v) atomic_add_return(1,(v))

#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))

#endif