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From: Daniel Phillips <phillips@bonn-fries.net>
To: Linus Torvalds <torvalds@transmeta.com>,
        Rik van Riel <riel@conectiva.com.br>
Subject: Re: [RFC] Page table sharing
Date: Tue, 19 Feb 2002 02:57:57 +0100
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On February 19, 2002 02:48 am, Linus Torvalds wrote:
> On Mon, 18 Feb 2002, Rik van Riel wrote:
> >
> > We'll need protection from the swapout code.
> 
> Absolutely NOT.
> 
> If the swapout code unshares or shares the PMD, that's a major bug.

What it will do is change entries on the page table.  We have to be sure
two processes don't read/evict the same page in at the same time.

> The swapout code doesn't need to know one way or the other, because the
> swapout code never actually touches the pmd itself, it just follows the
> pointers - it doesn't ever need to worry about the pmd counts at all.

That was my original, incomplete view of the situation at first as well.

-- 
Daniel
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