* Eric Blake (ebl...@redhat.com) wrote:
> On 02/16/2018 08:49 AM, Viktor Mihajlovski wrote:
>
> > >
> > > The HMP changes are non-trivial compared to v3, so I might have dropped
> > > all R-b and Acked-by to ensure they are looked at again.
> > >
> > > In fact,...
> > >
>
> > > > -
> > > > - if (cpu->value->CPU == monitor_get_cpu_index()) {
> > > > - active = '*';
> > > > - }
> > >
> > > The old code was doing multiple things - it was telling you the current
> > > HMP cpu (HMP has 'cpu' with no QMP counterpart, but if you are using
> > > HMP, knowing which cpu is the active target for future HMP commands that
> > > depend on the active target, this bit of information is important),
>
> > >
> > Thanks for the patience. I'll respin with the r/a-b's on patch 2/4
> > removed, but want to verify first that I can get the active cpu without
> > triggering cpu_synchronize_state via monitor_get_cpu_index...
>
> What does it matter? HMP is not the time-critical interface like QMP, so
> even if it has to synchronize things, you're no worse off than you were
> before when using HMP.
I guess it's not obvious that mon_get_cpu_index has that side effect;
although I can see why it's there since it guarantees correctness of all
the HMP data with one call; a comment might be nice to point it out.
But yes, I agree the performance cost there doesn't worry me for HMP.
Dave
> --
> Eric Blake, Principal Software Engineer
> Red Hat, Inc. +1-919-301-3266
> Virtualization: qemu.org | libvirt.org
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
