Date: Mon, 8 May 2006 20:38:55 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
To: Pekka Enberg <penberg@cs.helsinki.fi>
cc: Linus Torvalds <torvalds@osdl.org>,
       Daniel Hokka Zakrisson <daniel@hozac.com>, linux-kernel@vger.kernel.org,
       =?ISO-8859-1?Q?Bj=F6rn?= Steinbrink <B.Steinbrink@gmx.de>,
       greg@kroah.com, matthew@wil.cx, manfred@colorfullife.com, akpm@osdl.org
Subject: Re: [PATCH] fs: fcntl_setlease defies lease_init assumptions
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On Mon, 8 May 2006, Pekka Enberg wrote:

> > I think it sounds like it's worth it, but I'm not going to really push it.
> 
> Sounds good to me. Andrew?

virt_to_page is not cheap on NUMA.

On IA64 virt_to_page is:

#define virt_to_page(kaddr)     pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)

# define pfn_to_page(pfn)       (vmem_map + (pfn))

vmem_map is not a linear map but a virtual mapping that may require 
several faults to get the information.

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