On 24/09/21 20:51, Barry Song wrote:
> void update_siblings_masks(unsigned int cpuid)
> {
> struct cpu_topology *cpu_topo, *cpuid_topo = &cpu_topology[cpuid];
> @@ -617,6 +622,11 @@ void update_siblings_masks(unsigned int cpuid)
> if (cpuid_topo->package_id != cpu_topo->package_id)
> continue;
>
> + if (cpuid_topo->cluster_id == cpu_topo->cluster_id) {
> + cpumask_set_cpu(cpu, &cpuid_topo->cluster_sibling);
> + cpumask_set_cpu(cpuid, &cpu_topo->cluster_sibling);
> + }
> +
Hm so without cluster information (e.g. DT system), we have
->cluster_id=-1, we'll essentially copy the package mask into the cluster
mask.
The exposed cluster mask is still <= package mask which is sensible. Are we
fine with that, or do we need/want the mask to be empty in the -1 case? I'm
guessing userspace tools should check for either id!=-1 or if the exclusive
disjucntion of cluster vs package masks is non-empty.