From mboxrd@z Thu Jan  1 00:00:00 1970
From: glebn@voltaire.com (Gleb Natapov)
Subject: Re: [ofa-general] Re: [patch 5/6] mmu_notifier: Support for
	drivers with revers maps (f.e. for XPmem)
Date: Tue, 26 Feb 2008 09:21:37 +0200
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	<200802211520.03529.nickpiggin@yahoo.com.au>
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Cc: Andrea Arcangeli <andrea@qumranet.com>,
	Peter Zijlstra <a.p.zijlstra@chello.nl>, Izik Eidus <izike@qumranet.com>,
	Kanoj Sarcar <kanojsarcar@yahoo.com>,
	Roland Dreier <rdreier@cisco.com>, steiner@sgi.com,
	linux-kernel@vger.kernel.org, Avi Kivity <avi@qumranet.com>,
	linux-mm@kvack.org, daniel.blueman@quadrics.com,
	Robin Holt <holt@sgi.com>, general@lists.openfabrics.org,
	akpm@linux-foundation.org, Christoph Lameter <clameter@sgi.com>,
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To: Nick Piggin <nickpiggin@yahoo.com.au>
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On Tue, Feb 26, 2008 at 05:11:32PM +1100, Nick Piggin wrote:
> > You are missing one point here.  The MPI specifications that have
> > been out there for decades do not require the process use a library
> > for allocating the buffer.  I realize that is a horrible shortcoming,
> > but that is the world we live in.  Even if we could change that spec,
> 
> Can you change the spec?
Not really. It will break all existing codes. MPI-2 provides a call for
memory allocation (and it's beneficial to use this call for some interconnects),
but many (most?) applications are still written for MPI-1 and those that
are written for MPI-2 mostly uses the old habit of allocating memory by malloc(),
or even use stack or BSS memory for communication buffer purposes.

--
			Gleb.