Re: [patch 7/7] powerpc: lockless get_user_pages_fast

Nick Piggin
2008-06-10T03:15:26Z

On Mon, Jun 09, 2008 at 01:32:04AM -0700, Andrew Morton wrote:
> On Thu, 05 Jun 2008 19:43:07 +1000 npiggin@suse.de wrote:
>
> > Implement lockless get_user_pages_fast for powerpc. Page table existence is
> > guaranteed with RCU, and speculative page references are used to take a
> > reference to the pages without having a prior existence guarantee on them.
> >
>
> arch/powerpc/mm/gup.c: In function `get_user_pages_fast':
> arch/powerpc/mm/gup.c:156: error: `SLICE_LOW_TOP' undeclared (first use in this function)
> arch/powerpc/mm/gup.c:156: error: (Each undeclared identifier is reported only once
> arch/powerpc/mm/gup.c:156: error: for each function it appears in.)
> arch/powerpc/mm/gup.c:178: error: implicit declaration of function `get_slice_psize'
> arch/powerpc/mm/gup.c:178: error: `mmu_huge_psize' undeclared (first use in this function)
> arch/powerpc/mm/gup.c:182: error: implicit declaration of function `huge_pte_offset'
> arch/powerpc/mm/gup.c:182: warning: assignment makes pointer from integer without a cast
>
> with
>
> http://userweb.kernel.org/~akpm/config-g5.txt
>
> I don't immediately know why - adding asm/page.h to gup.c doesn't help.
> I'm suspecting a recursive include problem somewhere.
>
> I'll drop it, sorry - too much other stuff to fix over here.

No problem. Likely a clash with the hugepage patches.