Re: [libvirt] cpu flags

["Daniel P. Berrange" <berrange redhat com>]

On Wed, Sep 17, 2008 at 09:52:08AM -0400, Ben Guthro wrote:
> 
> 
> > I think the most likely place for exposing CPU flags would be in the
> > capabilities XML format. We do in fact already expose 3 flags there,
> > PAE, VMX and SVM. 
> 
> This looks like all of the info that I need - I guess I overlooked this part of the code prior to my message. 
> 
> The problem that I see currently is that despite the capabilities string containing the "host" tag, with this cpu info - it is up to each hypervisor driver to implement the broadcasting of host features.
> 
> For example - Xen will report PAE,VMX,SVM - but my ovirt node running KVM currently only reports the following:
> 
>   <host>
>     <cpu>
>       <arch>x86_64</arch>
>     </cpu>
>   </host>
> 
> It seems to me that it might be useful for some sort of "node" info 
> driver, where we might be able to share code for hypervisor independent 
> info about the physical machine it is running on. 

We already have a place for this useful reusable node info code - the 
cunningly named  src/nodeinfo.c :-)

> We should not have to re-write the scanning of /proc/cpuinfo in every 
> hypervisor driver, IMHO.

Totally agreed , this is why we put the node stuff in a separate nodeinfo.c
file even though only QEMU driver currently uses it. Which reminds me that
I need to hook it into the LXC driver.

Daniel
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