Re: [Qemu-devel] [PATCH] hw: add .min_cpus and .default_cpus fields to machine_class

[Emilio G. Cota]

On Tue, Nov 07, 2017 at 18:15:45 -0200, Eduardo Habkost wrote:
> On Fri, Nov 03, 2017 at 02:47:33PM -0400, Emilio G. Cota wrote:
> > @@ -4330,12 +4330,34 @@ int main(int argc, char **argv, char **envp)
> >      smp_parse(qemu_opts_find(qemu_find_opts("smp-opts"), NULL));
> >  
> >      machine_class->max_cpus = machine_class->max_cpus ?: 1; /* Default to 
> > UP */
> > +    machine_class->min_cpus = machine_class->min_cpus ?: 1;
> > +    machine_class->default_cpus = machine_class->default_cpus ?: 1;
> > +
> > +    /* if -smp is not set, default to mc->default_cpus */
> > +    if (!smp_cpus) {
> > +        smp_cpus = machine_class->default_cpus;
> > +        max_cpus = machine_class->default_cpus;
> > +    }
> 
> I suggest doing this before smp_parse(), so any validation of
> smp_cpus inside smp_parse will apply to the value we're setting
> here (e.g. the replay_add_blocker() call in smp_parse() will
> work).
(snip)
> > +    if (max_cpus < machine_class->min_cpus) {
> 
> smp_parse() already ensures max_cpus >= smp_cpus, and you are
> already checking if smp_cpus < machine_class->min_cpus above.  Is
> it really possible to trigger this error message?
> 
> Except for that, the patch looks good to me.

Both very good points! I've modified the patch accordingly.

Thanks,

                Emilio