Re: [PATCH v6 2/2] powerpc: Use cpu_smallcore_sibling_mask at SMT level on bigcores

From: Gautham R Shenoy
Date: Mon Aug 13 2018 - 08:07:45 EST


On Thu, Aug 09, 2018 at 06:26:57AM -0700, Srikar Dronamraju wrote:
> * Gautham R. Shenoy <ego@xxxxxxxxxxxxxxxxxx> [2018-08-09 11:02:08]:
>
> >
> > 3) ppc64_cpu --smt=2
> > SMT domain ceases to exist as each domain consists of just one
> > group.
> >
>
> When seen in isolation, the above looks as if ppc64_cpu --smt=2 o/p says
> " SMT domain ceases to exist...."

Ok. The intent was to say that one of the sched-domain level
collapses, thereby leaving only CACHE, DIE and NUMA. Will word it
better.

>
> > @@ -999,7 +1012,17 @@ static void add_cpu_to_masks(int cpu)
> > {
> > int first_thread = cpu_first_thread_sibling(cpu);
> > int chipid = cpu_to_chip_id(cpu);
> > - int i;
> > +
> > + struct thread_groups tg;
> > + int i, cpu_group_start = -1;
> > +
> > + if (has_big_cores) {
> > + struct device_node *dn = of_get_cpu_node(cpu, NULL);
> > +
>
> Not checking for validity of dn and no of_node_puts?

Will fix this. Thanks for catching this.

>
> > + parse_thread_groups(dn, &tg);
> > + cpu_group_start = get_cpu_thread_group_start(cpu, &tg);
> > + cpumask_set_cpu(cpu, cpu_smallcore_sibling_mask(cpu));
> > + }
> >
> > /*
> > * This CPU will not be in the online mask yet so we need to manually
>
> The rest looks good

Thanks for the review.


>