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Date: Tue, 23 Sep 2008 21:54:17 +1000
Message-ID: <87abdz84d2.wl%peter@chubb.wattle.id.au>
From: peter@chubb.wattle.id.au
To: Nick Piggin <npiggin@suse.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
       Jeremy Fitzhardinge <jeremy@goop.org>,
       Linux Memory Management List <linux-mm@kvack.org>,
       Linux Kernel list <linux-kernel@vger.kernel.org>,
       Hugh Dickins <hugh@veritas.com>
Subject: Re: PTE access rules & abstraction
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>>>>> "Nick" == Nick Piggin <npiggin@suse.de> writes:

Nick> On Tue, Sep 23, 2008 at 04:49:32PM +1000, Benjamin Herrenschmidt
Nick> wrote:

>> > What is the complete set of primitives we need?  I also noticed
>> that a > number of the existing pagetable operations are used only
>> once or twice > in the core code; I wonder if we really need such
>> special cases, or > whether we can make each arch pte operation
>> carry a bit more weight?
>> 
>> Yes, that was some of my concern. It's getting close to having one
>> API per call site :-)

Nick> I don't think that is a huge problem as such... if there was
Nick> lots of repeated uses of the API I'd also be concerned about mm/
Nick> code not being well factored :)

Is it worth taking another look at the page-table abstraction layer
that Darren Williams posted here last year?

PeterC