Hi Steve,
On 06/12/2018 21:28, Steve Sistare wrote:
[...]
> @@ -1621,7 +1626,22 @@ static void __sdt_free(const struct cpumask *cpu_map)
>
> static int sd_llc_alloc(struct sched_domain *sd)
> {
> - /* Allocate sd->shared data here. Empty for now. */
> + struct sched_domain_shared *sds = sd->shared;
> + struct cpumask *span = sched_domain_span(sd);
> + int nid = cpu_to_node(cpumask_first(span));
> + int flags = __GFP_ZERO | GFP_KERNEL;
> + struct sparsemask *mask;
> +
> + /*
> + * Allocate the bitmap if not already allocated. This is called for
> + * every CPU in the LLC but only allocates once per sd_llc_shared.
> + */
> + if (!sds->cfs_overload_cpus) {
> + mask = sparsemask_alloc_node(nr_cpu_ids, 3, flags, nid);
^^^^^^^^^^ ^^^
(1) (2)
(1): Is this necessary? Wouldn't cpumask_weight(span) suffice?
(2): Could this get a name somewhere? In v3 this was
SPARSEMASK_DENSITY_DEFAULT, I think it'd make sense to have it in
sched/sparsemask.c
> + if (!mask)
> + return 1;
> + sds->cfs_overload_cpus = mask;
> + }
>
> return 0;
> }
> @@ -1633,7 +1653,8 @@ static void sd_llc_free(struct sched_domain *sd)
> if (!sds)
> return;
>
> - /* Free data here. Empty for now. */
> + sparsemask_free(sds->cfs_overload_cpus);
> + sds->cfs_overload_cpus = NULL;
> }
>
> static int sd_llc_alloc_all(const struct cpumask *cpu_map, struct s_data *d)
>
