Messages in this thread | | | Date | Tue, 13 Nov 2012 14:51:08 +0100 | From | Ingo Molnar <> | Subject | Re: [PATCH 06/19] mm: numa: teach gup_fast about pmd_numa |
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* Mel Gorman <mgorman@suse.de> wrote:
> On Tue, Nov 13, 2012 at 11:07:36AM +0100, Ingo Molnar wrote: > > > > * Mel Gorman <mgorman@suse.de> wrote: > > > > > From: Andrea Arcangeli <aarcange@redhat.com> > > > > > > When scanning pmds, the pmd may be of numa type (_PAGE_PRESENT not set), > > > however the pte might be present. Therefore, gup_pmd_range() must return > > > 0 in this case to avoid losing a NUMA hinting page fault during gup_fast. > > > > > > Note: gup_fast will skip over non present ptes (like numa > > > types), so no explicit check is needed for the pte_numa case. > > > [...] > > > > So, why not fix all architectures that choose to expose > > pte_numa() and pmd_numa() methods - via the patch below? > > > > I'll pick it up. Thanks.
FYI, before you do too much restructuring work, that patch is already part of tip:numa/core, I'll push out our updated version of the tree later today.
Thanks,
Ingo
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