Re: separate domain info and vcpu context

[Kip Macy <kip.macy@gmail.com>]

> I would like both calls to return the number of VCPUs in use, but we
> still want the 'give me VCPU x or the next active one if it doesn't
> exist' enumeration scheme since VCPUs can potentially be sparse. Go for
> it!
> 

Why should GETDOMAINCONTEXT also return the number of active VCPUs?
That seems redundant. It would make more sense to me for it to take
exec_domain as an in/out variable. The value coming in would be the
index into the active CPUs and the out value would be the actual vcpu
number. So if you were running with 4 vcpus but only the 4th vcpu was
active, the caller would set exec_domain to 0 and then xen would set
exec_domain to 3.

I'd like to keep the number of iterations to 1, so just  to clarify
- in GETDOMAININFO, exec_domain will be changed to out variable
n_active_vcpus, ctxt will be removed.
- GETDOMAINCONTEXT will have two fields, (u16)exec_domain described
above and  (vcpu_guest_context_t *)ctxt

Thanks.
    
                    -Kip