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Date: Fri, 23 Mar 2007 12:15:12 +0100
From: Eric Dumazet <dada1@cosmosbay.com>
To: Andi Kleen <andi@firstfloor.org>
Cc: Pekka J Enberg <penberg@cs.helsinki.fi>,
       Christoph Lameter <christoph@lameter.com>,
       Andrew Morton <akpm@linux-foundation.org>,
       linux kernel <linux-kernel@vger.kernel.org>
Subject: [RFC] NUMA : could we introduce virt_to_nid() ?
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Hi Andi

Checking Christoph quicklist implementation, I found the same cache miss in free() than SLAB has.

/* common implementation *
int virt_to_nid(const void *addr)
{
	struct page *page = virt_to_page(addr); 
	return page_to_nid(page);
}

On some platforms (x86_64 for example), could we have a better implementation, not accessing struct page, but using phys_to_nid() ?

Thank you