This new helper expands to __atomic_test_and_set with acquire semantics where available; otherwise it expands to __sync_test_and_set, which has acquire semantics.
Signed-off-by: Emilio G. Cota <c...@braap.org> --- include/qemu/atomic.h | 3 +++ 1 file changed, 3 insertions(+) diff --git a/include/qemu/atomic.h b/include/qemu/atomic.h index 5bc4d6c..6061a46 100644 --- a/include/qemu/atomic.h +++ b/include/qemu/atomic.h @@ -113,6 +113,7 @@ } while(0) #endif +#define atomic_test_and_set_acquire(ptr) __atomic_test_and_set(ptr, __ATOMIC_ACQUIRE) /* All the remaining operations are fully sequentially consistent */ @@ -327,6 +328,8 @@ #endif #endif +#define atomic_test_and_set_acquire(ptr) __sync_lock_test_and_set(ptr, true) + /* Provide shorter names for GCC atomic builtins. */ #define atomic_fetch_inc(ptr) __sync_fetch_and_add(ptr, 1) #define atomic_fetch_dec(ptr) __sync_fetch_and_add(ptr, -1) -- 2.5.0
