[libvirt] [RFC PATCH 1/4] powerpc: Use Sysfs to gather host info

[Prerna Saxena]

On Mon, 10 Oct 2011 10:55:46 +0100
"Daniel P. Berrange" <berrange at redhat.com> wrote:

> On Sat, Oct 08, 2011 at 12:07:08AM +0530, Prerna Saxena wrote:
> > Libvirt presently depends on /proc/cpuinfo to gather information about
> > the x86 host. Parsing of /proc/cpuinfo is arch-specific; the
> > information fields are also not consistent.
> > A cleaner way would be to use Sysfs. Both x86 and PowerPC specific
> > information can be obtained from sysfs with different arch specific
> > parsing routines.
> > 
> > ---
> >  src/nodeinfo.c |  106 +++++++++++++++++++-------------------------------------
> >  1 files changed, 36 insertions(+), 70 deletions(-)
> > 
> > diff --git a/src/nodeinfo.c b/src/nodeinfo.c
> > index 6448b79..cdd339d 100644
> >  ...[snip]...
> 
> 
> I checked the output of 'virsh nodeinfo' before and after this patch on
> RHEL5 and RHEL-6 hosts, and it did not change.

This validates the patch :)
On an x86 system, virsh nodeinfo will give the same output; just that 
it will now depend on sysfs for learning about host topology, in place
of /proc/cpuinfo.
On a KVM-ppc64 machine, virsh nodeinfo will now work without having
to write a new parser for parsing /proc/cpuinfo for PowerPC.
> 
> When building, however, you get a compiele warning about the unused
> parameter 'need_hyperthreads'.  How come this was needed before, but
> is not used anymore ?  If it is redundant, you should remove the
> parameter entirely.

Agree, I'll do that in the next series of patches which I send.

Thanks,
-- 
Prerna Saxena

Linux Technology Centre,
IBM Systems and Technology Lab,
Bangalore, India