Re: [PATCH] - Fix get_model_name() for mixed cpu type systems

Matthew Wilcox
2006-10-19T21:21:37Z

On Thu, Oct 19, 2006 at 02:05:19PM -0700, Stephane Eranian wrote:
> I don't think this is going to work for the simple reason that perfmon supports per-thread
> monitoring. As a thread migrates from one CPU to another, its PMU state migrates with it.
> So you cannot reload a full Montecito state onto a Madison PMU. You will not crash, because
> write to unimplemented PMD are ignored but you will get false results. Even in system-wide
> tools are not prepare to cope with mixed configurations.

I suppose you could lock a thread to running only on the kind of CPU it
started running on. It's not a great solution though.