From 79d365a306c3af53d8a732fec79b76c0b285d816 Mon Sep 17 00:00:00 2001 From: Mathieu Desnoyers Date: Tue, 8 May 2007 00:34:36 -0700 Subject: [PATCH] atomic.h: add atomic64 cmpxchg, xchg and add_unless to x86_64 Signed-off-by: Mathieu Desnoyers Cc: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/asm-x86_64/atomic.h | 36 ++++++++++++++++++++++++++++++++---- 1 file changed, 32 insertions(+), 4 deletions(-) diff --git a/include/asm-x86_64/atomic.h b/include/asm-x86_64/atomic.h index 706ca4b60000..80e4fdbe2204 100644 --- a/include/asm-x86_64/atomic.h +++ b/include/asm-x86_64/atomic.h @@ -375,8 +375,8 @@ static __inline__ long atomic64_add_return(long i, atomic64_t *v) long __i = i; __asm__ __volatile__( LOCK_PREFIX "xaddq %0, %1;" - :"=r"(i) - :"m"(v->counter), "0"(i)); + :"+r" (i), "+m" (v->counter) + : : "memory"); return i + __i; } @@ -388,7 +388,10 @@ static __inline__ long atomic64_sub_return(long i, atomic64_t *v) #define atomic64_inc_return(v) (atomic64_add_return(1,v)) #define atomic64_dec_return(v) (atomic64_sub_return(1,v)) -#define atomic_cmpxchg(v, old, new) ((int)cmpxchg(&((v)->counter), old, new)) +#define atomic64_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), old, new)) +#define atomic64_xchg(v, new) (xchg(&((v)->counter), new)) + +#define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), old, new)) #define atomic_xchg(v, new) (xchg(&((v)->counter), new)) /** @@ -402,7 +405,7 @@ static __inline__ long atomic64_sub_return(long i, atomic64_t *v) */ #define atomic_add_unless(v, a, u) \ ({ \ - int c, old; \ + __typeof__((v)->counter) c, old; \ c = atomic_read(v); \ for (;;) { \ if (unlikely(c == (u))) \ @@ -416,6 +419,31 @@ static __inline__ long atomic64_sub_return(long i, atomic64_t *v) }) #define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0) +/** + * atomic64_add_unless - add unless the number is a given value + * @v: pointer of type atomic64_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 non-zero if @v was not @u, and zero otherwise. + */ +#define atomic64_add_unless(v, a, u) \ +({ \ + __typeof__((v)->counter) c, old; \ + c = atomic64_read(v); \ + for (;;) { \ + if (unlikely(c == (u))) \ + break; \ + old = atomic64_cmpxchg((v), c, c + (a)); \ + if (likely(old == c)) \ + break; \ + c = old; \ + } \ + c != (u); \ +}) +#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0) + /* These are x86-specific, used by some header files */ #define atomic_clear_mask(mask, addr) \ __asm__ __volatile__(LOCK_PREFIX "andl %0,%1" \ -- 2.30.2