Re: [PATCH] fs: fcntl_setlease defies lease_init assumptions

[Linus Torvalds <torvalds@osdl.org>]

On Mon, 8 May 2006, Christoph Lameter wrote:
>
> 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.

Right now the __cache_free() chain does "virt_to_page()" on NUMA 
regardless, through the

	#ifdef CONFIG_NUMA
	        {
	                struct slab *slabp;
	                slabp = virt_to_slab(objp);
	,,,

thing. The suggested patch obviously makes it do it _twice_: once to get 
the cachep, once to get the slabp. But some simple re-organization would 
make it do it just once, if we passed in the "struct page *" instead of 
the "struct cachep" - since in the end, every single path into the real 
core of the allocator does end up needing it.

			Linus
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