From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Jan Beulich" <jbeulich@novell.com>
Subject: Re: Linux questions
Date: Mon, 03 Dec 2007 11:40:28 +0000
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	<20071203112958.GB4930@implementation.labri.fr>
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To: Samuel Thibault <samuel.thibault@eu.citrix.com>
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>>> Samuel Thibault <samuel.thibault@eu.citrix.com> 03.12.07 12:29 >>>
>Jan Beulich, le Mon 03 Dec 2007 11:24:35 +0000, a =E9crit :
>> 2) What is the reason for the inconsistent use of rmb() vs. barrier() =
in
>> time-xen.c? It would seem to me that rmb() should be sufficient in all
>> cases.
>
>rmb() is more powerful than barrier(), not the converse.

Oh, sorry, I mixed barrier() with mb(). So the proposal would then simply
be the other way around (the use of locked operations or fence instructio=
ns
on x86 is really unnecessary as long as WC memory or non-temporal stores
don't need to be taken into consideration).

Jan