From: Kaigai Kohei Signed-off-by: KaiGai, Kohei Signed-off-by: Andrew Morton --- 25-akpm/include/asm-x86_64/atomic.h | 25 +++++++++++++++++++++++++ 1 files changed, 25 insertions(+) diff -puN include/asm-x86_64/atomic.h~atomic_inc_return-for-x86_64 include/asm-x86_64/atomic.h --- 25/include/asm-x86_64/atomic.h~atomic_inc_return-for-x86_64 2004-09-11 16:08:14.525894568 -0700 +++ 25-akpm/include/asm-x86_64/atomic.h 2004-09-11 16:08:14.528894112 -0700 @@ -178,6 +178,31 @@ static __inline__ int atomic_add_negativ return c; } +/** + * atomic_add_return - add and return + * @v: pointer of type atomic_t + * @i: integer value to add + * + * Atomically adds @i to @v and returns @i + @v + */ +static __inline__ int atomic_add_return(int i, atomic_t *v) +{ + int __i = i; + __asm__ __volatile__( + LOCK "xaddl %0, %1;" + :"=r"(i) + :"m"(v->counter), "0"(i)); + return i + __i; +} + +static __inline__ int atomic_sub_return(int i, atomic_t *v) +{ + return atomic_add_return(-i,v); +} + +#define atomic_inc_return(v) (atomic_add_return(1,v)) +#define atomic_dec_return(v) (atomic_sub_return(1,v)) + /* These are x86-specific, used by some header files */ #define atomic_clear_mask(mask, addr) \ __asm__ __volatile__(LOCK "andl %0,%1" \ _