[PATCH 0/3] powerpc: Instrument Hypervisor Calls

Olof Johansson olof at lixom.net
Mon Jul 17 09:09:15 EST 2006


On Sun, Jul 16, 2006 at 08:53:21PM -0200, Luke Browning wrote:

> > Just so people don't forget: this can't be done on all processors. For
> > example, PPC970 and POWER4 don't implement the PURR SPR. And it doesn't
> > make sense to use H_PURR to get the software emulated ones there. Not
> > really an issue on POWER4 since they don't do shared processor LPAR, but
> > on JS21 I think they might do?
> > 
> Isn't there someway to do a platform specific processor overlay, where you 
> get PURR if it exists and TB otherwise.

Sure, it's what we have cpu feature bits for. It's not a difficult
problem to solve, I was just reminding of the lack of SPRN_PURR on some
processors that can run hypervisors.


-Olof



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