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Re: [PATCH OSSTEST 1/2] exanime: test for SMT and add a host flag

  • To: Ian Jackson <ian.jackson@xxxxxxxxxx>
  • From: Roger Pau Monné <roger.pau@xxxxxxxxxx>
  • Date: Wed, 15 Apr 2020 15:47:22 +0200
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  • Delivery-date: Wed, 15 Apr 2020 13:47:38 +0000
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On Wed, Apr 15, 2020 at 02:04:35PM +0100, Ian Jackson wrote:
> Roger Pau Monne writes ("[PATCH OSSTEST 1/2] exanime: test for SMT and add a 
> host flag"):
> > Check if hosts have SMT based on the number of threads per core. A
> > value of threads per core different than 0 implies SMT support.
> ...
> > +logm("$ho->{Ident} threads per core: $threads");
> > +hostflag_putative_record($ho, "smt", !!$threads);
> This code LGTM but I wonder if it would be a good idea to start
> namespacing these kind of hardware feature flags.  cpu-*, hardware-*,
> feature-* maybe ?  Would you care to make a suggestion ?

cpu-smt seems fine if we plan to do similar namespacing with other
hardware features, I could see cpu-{smt,vmx,svm} and
devices-{iommu,sriov,ats} or some such for example.

If OTOH we don't want to be that fine grained I think
hw-{smt,iommu,vmx,...} would also be fine.

Not sure whether this has helped much. I guess my vote would be for
cpu-smt namespace.

Thanks, Roger.



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