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Subject: Re: [PATCH 1/3] powerpc: mm: make _PAGE_NUMA take effect
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Date: Mon, 09 Dec 2013 11:31:52 +1100
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Cc: Paul Mackerras <paulus@samba.org>, linuxppc-dev@lists.ozlabs.org,
 Liu Ping Fan <kernelfans@gmail.com>
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On Thu, 2013-12-05 at 16:23 +0530, Aneesh Kumar K.V wrote:
> Liu Ping Fan <kernelfans@gmail.com> writes:
> 
> > To enable the do_numa_page(), we should not fix _PAGE_NUMA in
> > hash_page(), so bail out for the case of pte_numa().

For some reason I don't have 2/3 and 3/3 in my mbox (though I do have
them on patchwork) so I'll reply to this one.

Overall, your statement that this is a faster path needs to be backed up
with numbers.

The code is complicated enough as it-is, such additional mess in the low
level hashing code requires a good justification, and also a
demonstration that it doesn't add overhead to the normal hash path.

Cheers,
Ben.