From 98c2aaf8be5baf7193be37fb28bce8e7327158bc Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Tue, 7 Apr 2009 11:30:17 +0200 Subject: [PATCH] x86, perfcounters: add atomic64_xchg() Complete atomic64_t support on the 32-bit side by adding atomic64_xch(). Cc: Peter Zijlstra LKML-Reference: <20090406094518.445450972@chello.nl> Signed-off-by: Ingo Molnar --- arch/x86/include/asm/atomic_32.h | 24 +++++++++++++++++++++--- 1 file changed, 21 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/atomic_32.h b/arch/x86/include/asm/atomic_32.h index 977250ed8b89..aff9f1fcdcd7 100644 --- a/arch/x86/include/asm/atomic_32.h +++ b/arch/x86/include/asm/atomic_32.h @@ -291,19 +291,37 @@ atomic64_cmpxchg(atomic64_t *ptr, unsigned long long old_val, } /** - * atomic64_set - set atomic64 variable + * atomic64_xchg - xchg atomic64 variable * @ptr: pointer to type atomic64_t * @new_val: value to assign + * @old_val: old value that was there * - * Atomically sets the value of @ptr to @new_val. + * Atomically xchgs the value of @ptr to @new_val and returns + * the old value. */ -static inline void atomic64_set(atomic64_t *ptr, unsigned long long new_val) + +static inline unsigned long long +atomic64_xchg(atomic64_t *ptr, unsigned long long new_val) { unsigned long long old_val; do { old_val = atomic_read(ptr); } while (atomic64_cmpxchg(ptr, old_val, new_val) != old_val); + + return old_val; +} + +/** + * atomic64_set - set atomic64 variable + * @ptr: pointer to type atomic64_t + * @new_val: value to assign + * + * Atomically sets the value of @ptr to @new_val. + */ +static inline void atomic64_set(atomic64_t *ptr, unsigned long long new_val) +{ + atomic64_xchg(ptr, new_val); } /** -- 2.34.1