Re: [PATCH 09/11] Powerpc/smp: Create coregroup domain

On Fri, Jul 17, 2020 at 01:49:26PM +0530, Gautham R Shenoy wrote:

quoted

+int cpu_to_coregroup_id(int cpu)
+{
+	return cpu_to_core_id(cpu);
+}

So, if has_coregroup_support() returns true, then since the core_group
identification is currently done through the core-id, the
coregroup_mask is going to be the same as the
cpu_core_mask/cpu_cpu_mask. Thus, we will be degenerating the DIE
domain. Right ? Instead we could have kept the core-group to be a
single bigcore by default, so that those domains can get degenerated
preserving the legacy SMT, DIE, NUMA hierarchy.

Never mind, got confused with core_id and cpu_core_mask (which
corresponds to the cores of a chip).  cpu_to_core_id() does exactly
what we have described above. Sorry for the noise.

I am ok with this patch, except that I would request if all the
changes to the topology structure be done within a single function for
ease of tracking it instead of distributing it all over the code.

quoted

+
 static int topology_update_init(void)
 {
 	start_topology_update();
-- 
2.17.1