Re: [PATCH] MIPS: Add fast get_user_pages

[Ralf Baechle <ralf@linux-mips.org>]

On Fri, Nov 04, 2011 at 03:16:03PM +0000, Ralf Baechle wrote:

> On Fri, Oct 28, 2011 at 09:26:23PM +0800, Hillf Danton wrote:
> 
> When we were chasing the TLB crash recently for a while I was suspecting
> the default get_user_fast implementation so I ported gup.c from x86 but I
> never really finished it, so thanks for ridding me of one item from my
> to do list.
> 
> This probably wants some more testing in particular on 32-bit systems with
> 64-bit pagetables such as some Alchemy configurations or 32-bit kernels
> on Sibyte systems.
> 
> I fixed up a reject in arch/mips/mm/Makefile due to whitespace differences
> and queued the patch for 3.3.
> 
> Have you made any benchmarks of the new gup.c?

Hitting this one in a non-hugepage build of upstream-sfr:

  CC      arch/mips/mm/gup.o
arch/mips/mm/gup.c:70:51: error: redefinition of ‘get_huge_page_tail’
include/linux/mm.h:379:51: note: previous definition of ‘get_huge_page_tail’ was here
make[2]: *** [arch/mips/mm/gup.o] Error 1
make[1]: *** [arch/mips/mm] Error 2
make: *** [arch/mips] Error 2

I fixed this one up by removing the local definition of get_huge_page_tail
but you may want to re-test.

  Ralf