Re: [PATCH v2 0/2] cpu: pseries: Offline state framework.

2009-09-25 Thread Arjan van de Ven
On Fri, 25 Sep 2009 12:55:49 +0530 Vaidyanathan Srinivasan wrote: > > I obviously can't speak for p-series cpus, just wanted to point out > > that there is no universal truth about "offlining saves power". > > Hi Arjan, > > As you have said, on some cpus the extra effort of offlining does not >

Re: [PATCH v2 0/2] cpu: pseries: Offline state framework.

2009-09-25 Thread Vaidyanathan Srinivasan
* Arjan van de Ven [2009-09-24 13:41:23]: > On Thu, 24 Sep 2009 13:33:07 +0200 > Peter Zijlstra wrote: > > > On Thu, 2009-09-24 at 18:38 +1000, Benjamin Herrenschmidt wrote: > > > On Thu, 2009-09-24 at 09:51 +0200, Peter Zijlstra wrote: > > > > > I don't quite follow your logic here. This is us

Re: [PATCH v2 0/2] cpu: pseries: Offline state framework.

2009-09-24 Thread Arjan van de Ven
On Thu, 24 Sep 2009 13:33:07 +0200 Peter Zijlstra wrote: > On Thu, 2009-09-24 at 18:38 +1000, Benjamin Herrenschmidt wrote: > > On Thu, 2009-09-24 at 09:51 +0200, Peter Zijlstra wrote: > > > > I don't quite follow your logic here. This is useful for more > > > > than just hypervisors. For example

Re: [PATCH v2 0/2] cpu: pseries: Offline state framework.

2009-09-24 Thread Peter Zijlstra
On Thu, 2009-09-24 at 18:38 +1000, Benjamin Herrenschmidt wrote: > On Thu, 2009-09-24 at 09:51 +0200, Peter Zijlstra wrote: > > > I don't quite follow your logic here. This is useful for more than just > > > hypervisors. For example, take the HV out of the picture for a moment > > > and imagine tha

Re: [PATCH v2 0/2] cpu: pseries: Offline state framework.

2009-09-24 Thread Benjamin Herrenschmidt
On Thu, 2009-09-24 at 09:51 +0200, Peter Zijlstra wrote: > > I don't quite follow your logic here. This is useful for more than just > > hypervisors. For example, take the HV out of the picture for a moment > > and imagine that the HW has the ability to offline CPU in various power > > levels, with

Re: [PATCH v2 0/2] cpu: pseries: Offline state framework.

2009-09-24 Thread Peter Zijlstra
On Thu, 2009-09-24 at 10:48 +1000, Benjamin Herrenschmidt wrote: > On Wed, 2009-09-02 at 07:33 +0200, Peter Zijlstra wrote: > > > > I'm still thinking this is a bad idea. > > > > The OS should only know about online/offline. > > > > Use the hypervisor interface to deal with the cpu once its offl

Re: [PATCH v2 0/2] cpu: pseries: Offline state framework.

2009-09-23 Thread Benjamin Herrenschmidt
On Wed, 2009-09-02 at 07:33 +0200, Peter Zijlstra wrote: > > I'm still thinking this is a bad idea. > > The OS should only know about online/offline. > > Use the hypervisor interface to deal with the cpu once its offline. > > That is, I think this interface you propose is a layering violation.

Re: [PATCH v2 0/2] cpu: pseries: Offline state framework.

2009-09-02 Thread Pavel Machek
On Wed 2009-09-02 07:33:31, Peter Zijlstra wrote: > On Fri, 2009-08-28 at 15:30 +0530, Gautham R Shenoy wrote: > > Hi, > > > > This is the version 2 of the patch series to provide a cpu-offline framework > > that enables the administrators choose the state the offline CPU must be put > > into when

Re: [PATCH v2 0/2] cpu: pseries: Offline state framework.

2009-09-01 Thread Peter Zijlstra
On Fri, 2009-08-28 at 15:30 +0530, Gautham R Shenoy wrote: > Hi, > > This is the version 2 of the patch series to provide a cpu-offline framework > that enables the administrators choose the state the offline CPU must be put > into when multiple such states are exposed by the underlying architectu

[PATCH v2 0/2] cpu: pseries: Offline state framework.

2009-08-28 Thread Gautham R Shenoy
Hi, This is the version 2 of the patch series to provide a cpu-offline framework that enables the administrators choose the state the offline CPU must be put into when multiple such states are exposed by the underlying architecture. Version 1 of the Patch can be found here: http://lkml.org/lkml/2