From: Qiaowei Ren Date: Sat, 14 Dec 2013 06:25:03 +0000 (+0800) Subject: x86: replace futex_atomic_cmpxchg_inatomic() with user_atomic_cmpxchg_inatomic X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=0ee3b6f87d4d748d5362cb47ff33fa1553805cb4;p=linux-beck.git x86: replace futex_atomic_cmpxchg_inatomic() with user_atomic_cmpxchg_inatomic futex_atomic_cmpxchg_inatomic() is simply the 32-bit implementation of user_atomic_cmpxchg_inatomic(), which in turn is simply a generalization of the original code in futex_atomic_cmpxchg_inatomic(). Use the newly generalized user_atomic_cmpxchg_inatomic() as the futex implementation, too. [ hpa: retain the inline in futex.h rather than changing it to a macro ] Signed-off-by: Qiaowei Ren Link: http://lkml.kernel.org/r/1387002303-6620-2-git-send-email-qiaowei.ren@intel.com Signed-off-by: H. Peter Anvin Cc: Peter Zijlstra --- diff --git a/arch/x86/include/asm/futex.h b/arch/x86/include/asm/futex.h index be27ba1e947a..b4c1f5453436 100644 --- a/arch/x86/include/asm/futex.h +++ b/arch/x86/include/asm/futex.h @@ -110,26 +110,7 @@ static inline int futex_atomic_op_inuser(int encoded_op, u32 __user *uaddr) static inline int futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, u32 oldval, u32 newval) { - int ret = 0; - - if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))) - return -EFAULT; - - asm volatile("\t" ASM_STAC "\n" - "1:\t" LOCK_PREFIX "cmpxchgl %4, %2\n" - "2:\t" ASM_CLAC "\n" - "\t.section .fixup, \"ax\"\n" - "3:\tmov %3, %0\n" - "\tjmp 2b\n" - "\t.previous\n" - _ASM_EXTABLE(1b, 3b) - : "+r" (ret), "=a" (oldval), "+m" (*uaddr) - : "i" (-EFAULT), "r" (newval), "1" (oldval) - : "memory" - ); - - *uval = oldval; - return ret; + return user_atomic_cmpxchg_inatomic(uval, uaddr, oldval, newval); } #endif