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Date: Tue, 20 Mar 2007 12:43:27 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
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To: Paul Mackerras <paulus@samba.org>
cc: akpm@linux-foundation.org, linux-mm@vger.kernel.org,
       linux-kernel@vger.kernel.org
Subject: Re: [QUICKLIST 1/5] Quicklists for page table pages V3
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On Tue, 20 Mar 2007, Paul Mackerras wrote:

> Christoph Lameter writes:
> 
> > +static inline void *quicklist_alloc(int nr, gfp_t flags, void (*ctor)(void *))
> > +{
> 
> ...
> 
> > +	p = (void *)__get_free_page(flags | __GFP_ZERO);
> 
> This will cause problems on 64-bit powerpc, at least with 4k pages,
> since the pmd and pgd levels only use 1/4 of a page.

quicklists are only useful for page sized allocations. If you have smaller 
sizes then by all means continue the use of slab. You do not have a page 
struct for each pmd, pgd  to do bad things with (like i386) so everything 
is just fine.