Re: [RFC v2 -tip 0/3] x86: reduce fixup of uaccess

H. Peter Anvin
2009-01-24T04:40:26Z

Hiroshi Shimamoto wrote:
> This patch series redues fixup code for exceptions of uaccess in signal.
>
> There is a lot of fixup code which is generated by using __{get|put}_user.
> I think that code can be reduced. The concept is that to add uaccess_err in
> thread_info and set it to -EFAULT on exception, finally check this value on
> the last of function.
>
> The code size reductions are below;
> $ size *signal*.o.*
> text data bss dec hex filename
> 4596 0 0 4596 11f4 ia32_signal.o.new
> 6006 0 0 6006 1776 ia32_signal.o.old
> 3583 0 0 3583 dff signal.o.new
> 4540 0 0 4540 11bc signal.o.old
> 3863 0 0 3863 f17 signal32.o.new
> 4876 0 0 4876 130c signal32.o.old
> [ signal32.o means signal.o on 32-bit. ]
>

Applied to tip:x86/uaccess. I haven't tested it much yet, but at least
a visual lookover looks good.

Thanks!

-hpa

--
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.