From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrea Arcangeli <andrea@qumranet.com>
Subject: Re: [patch 2/6] mmu_notifier: Callbacks to invalidate
	address	ranges
Date: Thu, 28 Feb 2008 00:57:24 +0100
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Cc: Nick Piggin <nickpiggin@yahoo.com.au>, steiner@sgi.com,
	Peter Zijlstra <a.p.zijlstra@chello.nl>, linux-mm@kvack.org,
	Kanoj Sarcar <kanojsarcar@yahoo.com>,
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To: Christoph Lameter <clameter@sgi.com>
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On Wed, Feb 27, 2008 at 02:23:29PM -0800, Christoph Lameter wrote:
> How would that work? You rely on the pte locking. Thus calls are all in an 

I don't rely on the pte locking in #v7, exactly to satisfy GRU
(so far purely theoretical) performance complains.

> atomic context. I think we need a general scheme that allows sleeping when 

Calls are still in atomic context until we change the i_mmap_lock to a
mutex under a CONFIG_XPMEM, or unless we boost mm_users, drop the lock
and restart the loop at every different mm. In any case those changes
should be under CONFIG_XPMEM IMHO given desktop users definitely don't
need this (regular non-blocking mmu notifiers in my patch are all what
a desktop user need as far as I can tell).

> references are invalidates. Even the GRU has performance issues when using 
> the KVM patch.

GRU will perform the same with #v7 or V8.

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