Re: [PATCH v3 2/2] acpi, gicv3-its, numa: Adding numa node mapping for gic-its units

Lorenzo Pieralisi
2017-06-21T09:27:35Z

On Wed, Jun 21, 2017 at 11:45:43AM +0530, Ganapatrao Kulkarni wrote:
> Add code to parse SRAT ITS Affinity sub table as defined in ACPI 6.2
> Later in per device probe, ITS devices are mapped to
> numa node using ITS id to proximity domain mapping.
>
> Signed-off-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com>
> ---
> drivers/irqchip/irq-gic-v3-its.c | 80 +++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 79 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
> index 45ea1933..88cfb32 100644
> --- a/drivers/irqchip/irq-gic-v3-its.c
> +++ b/drivers/irqchip/irq-gic-v3-its.c
> @@ -1833,6 +1833,82 @@ static int __init its_of_probe(struct device_node *node)
>
> #define ACPI_GICV3_ITS_MEM_SIZE (SZ_128K)
>
> +#ifdef CONFIG_ACPI_NUMA
> +struct its_srat_map {
> + u32 numa_node; /* numa node id */
> + u32 its_id; /* GIC ITS ID */
> +};
> +
> +static struct its_srat_map its_srat_maps[MAX_NUMNODES] __initdata = {
> + [0 ... MAX_NUMNODES - 1] = {NUMA_NO_NODE, UINT_MAX} };

Nit: UINT_MAX is as valid as 0 as its_id (but the intent here is to make
it look like an invalid value), given that the its_in_srat counter
defines what entries are valid I do not necessarily see the point in
initializing with something that is a valid value != 0.

> +static int its_in_srat __initdata;
> +
> +static int __init
> +acpi_get_its_numa_node(u32 its_id)
> +{
> + int i;
> +
> + for (i = 0; i < its_in_srat; i++) {
> + if (its_id == its_srat_maps[i].its_id)
> + return its_srat_maps[i].numa_node;
> + }
> + return NUMA_NO_NODE;
> +}
> +
> +static int __init
> +gic_acpi_parse_srat_its(struct acpi_subtable_header *header,
> + const unsigned long end)
> +{
> + int pxm, node;
> + struct acpi_srat_its_affinity *its_affinity;
> +
> + its_affinity = (struct acpi_srat_its_affinity *)header;
> + if (!its_affinity)
> + return -EINVAL;
> +
> + if (its_affinity->header.length <
> + sizeof(struct acpi_srat_its_affinity)) {
> + pr_err("SRAT:ITS: Invalid SRAT header length: %d\n",
> + its_affinity->header.length);
> + return -EINVAL;
> + }
> +
> + if (its_in_srat >= MAX_NUMNODES) {
> + pr_err("SRAT:ITS: ITS devices exceeding max count[%d]\n",
> + MAX_NUMNODES);
> + return -EINVAL;
> + }
> +
> + pxm = its_affinity->proximity_domain;
> + node = acpi_map_pxm_to_node(pxm);
> +
> + if (node == NUMA_NO_NODE || node >= MAX_NUMNODES) {
> + pr_err("SRAT:ITS: Invalid numa node %d\n", node);
> + return -EINVAL;

As Marc mentioned you should bail out here but continue parsing entries,
aka "return 0";

Thanks,
Lorenzo

> + }
> +
> + its_srat_maps[its_in_srat].numa_node = node;
> + its_srat_maps[its_in_srat].its_id = its_affinity->its_id;
> + its_in_srat++;
> + pr_info("ACPI: NUMA: SRAT: ITS: PXM %d -> ITS_ID %d -> NODE %d\n",
> + pxm, its_affinity->its_id, node);
> +
> + return 0;
> +}
> +
> +static int __init acpi_table_parse_srat_its(void)
> +{
> + return acpi_table_parse_entries(ACPI_SIG_SRAT,
> + sizeof(struct acpi_table_srat),
> + ACPI_SRAT_TYPE_GIC_ITS_AFFINITY,
> + gic_acpi_parse_srat_its, 0);
> +}
> +#else
> +#define acpi_table_parse_srat_its() do { } while (0)
> +#define acpi_get_its_numa_node(its_id) NUMA_NO_NODE
> +#endif
> +
> static int __init gic_acpi_parse_madt_its(struct acpi_subtable_header *header,
> const unsigned long end)
> {
> @@ -1861,7 +1937,8 @@ static int __init gic_acpi_parse_madt_its(struct acpi_subtable_header *header,
> goto dom_err;
> }
>
> - err = its_probe_one(&res, dom_handle, NUMA_NO_NODE);
> + err = its_probe_one(&res, dom_handle,
> + acpi_get_its_numa_node(its_entry->translation_id));
> if (!err)
> return 0;
>
> @@ -1873,6 +1950,7 @@ static int __init gic_acpi_parse_madt_its(struct acpi_subtable_header *header,
>
> static void __init its_acpi_probe(void)
> {
> + acpi_table_parse_srat_its();
> acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_TRANSLATOR,
> gic_acpi_parse_madt_its, 0);
> }
> --
> 1.8.1.4
>