On Fri, 19 Feb 2016, Jacob Pan wrote:
> @@ -1380,6 +1375,7 @@ static int rapl_detect_topology(void)
> int i;
> int phy_package_id;
> struct rapl_package *new_package, *rp;
> + int lead_cpu;
>
> for_each_online_cpu(i) {
> phy_package_id = topology_physical_package_id(i);
> @@ -1392,7 +1388,11 @@ static int rapl_detect_topology(void)
> /* add the new package to the list */
> new_package->id = phy_package_id;
> new_package->nr_cpus = 1;
> -
> + /* find the first active cpu of the package */
> + lead_cpu = cpumask_any_and(topology_core_cpumask(i),
> + cpumask_of(i));
Yuck. Why any_and? The result is i, simply because i is online otherwise you
would not be there.
> + if (lead_cpu < nr_cpu_ids)
> + new_package->lead_cpu = lead_cpu;
So the above is identical to
new_package->lead_cpu = lead_cpu;
Hmm?
> @@ -1500,6 +1503,15 @@ static int rapl_cpu_callback(struct notifier_block
> *nfb,
> break;
> if (--rp->nr_cpus == 0)
> rapl_remove_package(rp);
> + else if (cpu == rp->lead_cpu) {
> + /* choose another active cpu in the package */
> + lead_cpu = cpumask_any_but(topology_core_cpumask(cpu),
> cpu);
This part is correct.
Thanks,
tglx
