Re: [PATCH v4 18/20] arch_topology: Set cluster identifier in each core/thread from /cpu-map

From: Ionela Voinescu
Date: Mon Jun 27 2022 - 09:47:23 EST


On Tuesday 21 Jun 2022 at 20:20:32 (+0100), Sudeep Holla wrote:
> Let us set the cluster identifier as parsed from the device tree
> cluster nodes within /cpu-map.
>
> We don't support nesting of clusters yet as there are no real hardware
> to support clusters of clusters.
>
> Signed-off-by: Sudeep Holla <sudeep.holla@xxxxxxx>
> ---
> drivers/base/arch_topology.c | 13 ++++++++-----
> 1 file changed, 8 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c
> index 39be5dbaf4da..75604f783bfc 100644
> --- a/drivers/base/arch_topology.c
> +++ b/drivers/base/arch_topology.c
> @@ -497,7 +497,7 @@ static int __init get_cpu_for_node(struct device_node *node)
> }
>
> static int __init parse_core(struct device_node *core, int package_id,
> - int core_id)
> + int cluster_id, int core_id)
> {
> char name[20];
> bool leaf = true;
> @@ -513,6 +513,7 @@ static int __init parse_core(struct device_node *core, int package_id,
> cpu = get_cpu_for_node(t);
> if (cpu >= 0) {
> cpu_topology[cpu].package_id = package_id;
> + cpu_topology[cpu].cluster_id = cluster_id;
> cpu_topology[cpu].core_id = core_id;
> cpu_topology[cpu].thread_id = i;
> } else if (cpu != -ENODEV) {
> @@ -534,6 +535,7 @@ static int __init parse_core(struct device_node *core, int package_id,
> }
>
> cpu_topology[cpu].package_id = package_id;
> + cpu_topology[cpu].cluster_id = cluster_id;
> cpu_topology[cpu].core_id = core_id;
> } else if (leaf && cpu != -ENODEV) {
> pr_err("%pOF: Can't get CPU for leaf core\n", core);
> @@ -543,7 +545,8 @@ static int __init parse_core(struct device_node *core, int package_id,
> return 0;
> }
>
> -static int __init parse_cluster(struct device_node *cluster, int depth)
> +static int __init
> +parse_cluster(struct device_node *cluster, int cluster_id, int depth)
> {
> char name[20];
> bool leaf = true;
> @@ -563,7 +566,7 @@ static int __init parse_cluster(struct device_node *cluster, int depth)
> c = of_get_child_by_name(cluster, name);
> if (c) {
> leaf = false;
> - ret = parse_cluster(c, depth + 1);
> + ret = parse_cluster(c, i, depth + 1);
> of_node_put(c);
> if (ret != 0)
> return ret;
> @@ -587,7 +590,7 @@ static int __init parse_cluster(struct device_node *cluster, int depth)
> }
>
> if (leaf) {
> - ret = parse_core(c, 0, core_id++);
> + ret = parse_core(c, 0, cluster_id, core_id++);
> } else {
> pr_err("%pOF: Non-leaf cluster with core %s\n",
> cluster, name);
> @@ -626,7 +629,7 @@ static int __init parse_dt_topology(void)
> if (!map)
> goto out;
>
> - ret = parse_cluster(map, 0);
> + ret = parse_cluster(map, -1, 0);
> if (ret != 0)
> goto out_map;
>
> --
> 2.36.1
>

Reviewed-by: Ionela Voinescu <ionela.voinescu@xxxxxxx>

Thanks,
Ionela.