Date: Fri, 29 Feb 2008 13:03:16 -0800 (PST)
From: Christoph Lameter <clameter@sgi.com>
To: Andrea Arcangeli <andrea@qumranet.com>
cc: Nick Piggin <nickpiggin@yahoo.com.au>, akpm@linux-foundation.org,
       Robin Holt <holt@sgi.com>, Avi Kivity <avi@qumranet.com>,
       Izik Eidus <izike@qumranet.com>, kvm-devel@lists.sourceforge.net,
       Peter Zijlstra <a.p.zijlstra@chello.nl>, general@lists.openfabrics.org,
       Steve Wise <swise@opengridcomputing.com>,
       Roland Dreier <rdreier@cisco.com>, Kanoj Sarcar <kanojsarcar@yahoo.com>,
       steiner@sgi.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org,
       daniel.blueman@quadrics.com
Subject: Re: [patch 2/6] mmu_notifier: Callbacks to invalidate address ranges
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On Fri, 29 Feb 2008, Andrea Arcangeli wrote:

> Agreed. I just thought xpmem needed an invalidate-by-page, but
> I'm glad if xpmem can go in sync with the KVM/GRU/DRI model in this
> regard.

That means we need both the anon_vma locks and the i_mmap_lock to become 
semaphores. I think semaphores are better than mutexes. Rik and Lee saw 
some performance improvements because list can be traversed in parallel 
when the anon_vma lock is switched to be a rw lock.

Sounds like we get to a conceptually clean version here?

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