Messages in this thread | | | Date | Wed, 9 Apr 2014 17:12:24 -0700 | Subject | Re: [RFC PATCH 0/5] Use an alternative to _PAGE_PROTNONE for _PAGE_NUMA v2 | From | Linus Torvalds <> |
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On Wed, Apr 9, 2014 at 4:34 PM, H. Peter Anvin <hpa@zytor.com> wrote: > > How painful would it be to get rid of _PAGE_NUMA entirely? Page bits > are a highly precious commodity and saving one would be valuable.
I don't think _PAGE_NUMA is a problem. It's only set when the page is not present, so we have tons of bits then.
Now, that's still inconvenient for the 32-bit pte case, because we do *not* have tons of bits for non-present cases since we need them for the swap indexes.
This is different from _PAGE_SOFT_DIRTY, which we do need for both present and swapped-out entries.
Or am I missing something?
Linus
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