GCC doesn't realize that get_user, put_user, and their __ variants are unlikely to fail. Tell it.
I noticed this while playing with the C entry code. Before: text data bss dec hex filename 21828763 5194760 1277952 28301475 1afd8a3 baseline After: text data bss dec hex filename 21828379 5194760 1277952 28301091 1afd723 vmlinux Signed-off-by: Andy Lutomirski <[email protected]> --- arch/x86/include/asm/uaccess.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h index a8df874f3e88..3e911c68876e 100644 --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -182,7 +182,7 @@ __typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL)) : "=a" (__ret_gu), "=r" (__val_gu) \ : "0" (ptr), "i" (sizeof(*(ptr)))); \ (x) = (__force __typeof__(*(ptr))) __val_gu; \ - __ret_gu; \ + __builtin_expect(__ret_gu, 0); \ }) #define __put_user_x(size, x, ptr, __ret_pu) \ @@ -278,7 +278,7 @@ extern void __put_user_8(void); __put_user_x(X, __pu_val, ptr, __ret_pu); \ break; \ } \ - __ret_pu; \ + __builtin_expect(__ret_pu, 0); \ }) #define __put_user_size(x, ptr, size, retval, errret) \ @@ -401,7 +401,7 @@ do { \ ({ \ int __pu_err; \ __put_user_size((x), (ptr), (size), __pu_err, -EFAULT); \ - __pu_err; \ + __builtin_expect(__pu_err, 0); \ }) #define __get_user_nocheck(x, ptr, size) \ @@ -410,7 +410,7 @@ do { \ unsigned long __gu_val; \ __get_user_size(__gu_val, (ptr), (size), __gu_err, -EFAULT); \ (x) = (__force __typeof__(*(ptr)))__gu_val; \ - __gu_err; \ + __builtin_expect(__gu_err, 0); \ }) /* FIXME: this hack is definitely wrong -AK */ -- 2.4.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
