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Date: Wed, 7 May 2008 18:12:32 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
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To: Linus Torvalds <torvalds@linux-foundation.org>
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Subject: Re: [PATCH 08 of 11] anon-vma-rwsem
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On Wed, 7 May 2008, Linus Torvalds wrote:

> and you're now done. You have your "mm_lock()" (which still needs to be 
> renamed - it should be a "mmu_notifier_lock()" or something like that), 
> but you don't need the insane sorting. At most you apparently need a way 
> to recognize duplicates (so that you don't deadlock on yourself), which 
> looks like a simple bit-per-vma.

Andrea's mm_lock could have wider impact. It is the first effective 
way that I have seen of temporarily holding off reclaim from an address 
space. It sure is a brute force approach.