RE: [PATCH 1/3] AMD Family10h+ IBS support for oProfile driver: Setup routines

From: Kasindorf, Barry
Date: Wed Jun 11 2008 - 14:10:49 EST


This is a thorny problem.
A mistake was made in the name almost 2 years ago. The longer we leave
it wrong the harder it will be to change. To use IBS, the major feature
added by this patch, you HAVE to upgrade the user tools anyway. If there
was a way to have the driver send both I would have done that. So far it
is a very narrow window of time that would have a problem.

If I get too much pushback I can leave it, but the code that sends
Family10 has not been present in the kernel for very long at this point,
and it should be fixed. When the patch that added Family10 went in it
had the same issue, before it would have reported Family8 and worked
with the older userspace tools, adding this would get a cpu type unset
error.

-Barry


-----Original Message-----
From: Pavel Machek [mailto:pavel@xxxxxxx]
Sent: Wednesday, June 11, 2008 2:01 PM
To: Kasindorf, Barry
Cc: Andi Kleen; linux-kernel@xxxxxxxxxxxxxxx
Subject: Re: [PATCH 1/3] AMD Family10h+ IBS support for oProfile driver:
Setup routines

On Wed 2008-06-11 09:29:29, Kasindorf, Barry wrote:
> Yes,
> This is visible to userspace. The corresponding changes to the
usermode
> code have been sent to the oProfile list. The confusion is that it is
> not AMD Family 10 but it is Family 16(10h). This can be confusing so
we
> changed it.

...so we require users to upgrade userspace tools at the same moment
they upgrade kernel, and they can't go to the old kernel. Bad.

(Please mention userspace change in changelog).

I don't think potential for confusion is that big... and perhaps you
can do s/10/10h/ in userspace tools?

--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures)
http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html


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