Re: [PATCH v3 0/3] cpu: pseries: Cpu offline states framework

From: Pavel Machek
Date: Sat Sep 26 2009 - 05:55:38 EST


On Tue 2009-09-15 14:11:41, Peter Zijlstra wrote:
> On Tue, 2009-09-15 at 17:36 +0530, Gautham R Shenoy wrote:
> > This patchset contains the offline state driver implemented for
> > pSeries. For pSeries, we define three available_hotplug_states. They are:
> >
> > online: The processor is online.
> >
> > offline: This is the the default behaviour when the cpu is offlined
> > even in the absense of this driver. The CPU would call make an
> > rtas_stop_self() call and hand over the CPU back to the resource pool,
> > thereby effectively deallocating that vCPU from the LPAR.
> > NOTE: This would result in a configuration change to the LPAR
> > which is visible to the outside world.
> >
> > inactive: This cedes the vCPU to the hypervisor with a cede latency
> > specifier value 2.
> > NOTE: This option does not result in a configuration change
> > and the vCPU would be still entitled to the LPAR to which it earlier
> > belong to.
> >
> > Any feedback on the patchset will be immensely valuable.
>
> I still think its a layering violation... its the hypervisor manager
> that should be bothered in what state an off-lined cpu is in.

Agreed. Proposed interface is ugly.

--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/