From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.fraser@eu.citrix.com>
Subject: Re: [PATCH] Add hypercall to mark superpages to improve
	performance
Date: Fri, 30 Apr 2010 14:30:11 -0700
Message-ID: <C80099F3.1198F%keir.fraser@eu.citrix.com>
References: <201004301443.23350.dcm@mccr.org>
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To: Dave McCracken <dcm@mccr.org>
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On 30/04/2010 12:43, "Dave McCracken" <dcm@mccr.org> wrote:

>> Secondly, I don't really believe that the mark/unmark
>> hypercalls are race-free -- bearing in mind, that other mappings (superpage
>> or otherwise) can be constructed or deleted in parallel on other cpus.
> 
> I'll look into what can be done to prevent races.  I suspect some races we
> don't care about.

I mean I think there are probably races that can result in inconsistent
reference counts. I reckon I'll be able to find some when I'm back from
travelling next week. Obviously, any such race would be unacceptable.

 -- Keir