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

[Gautham R Shenoy <ego@linux.vnet.ibm.com>]

On Thu, Aug 09, 2018 at 06:26:57AM -0700, Srikar Dronamraju wrote:
> * Gautham R. Shenoy <ego@linux.vnet.ibm.com> [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.


>