Hi Sudeep, On 23/06/2025 14:08, Sudeep Holla wrote: > On Thu, Jun 12, 2025 at 05:13:33PM +0000, James Morse wrote: >> The PPTT describes CPUs and caches, as well as processor containers. >> The ACPI table for MPAM describes the set of CPUs that can access an MSC >> with the UID of a processor container. >> >> Add a helper to find the processor container by its id, then walk >> the possible CPUs to fill a cpumask with the CPUs that have this >> processor container as a parent. >> diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c >> index 54676e3d82dd..aaf9b5a26d07 100644 >> --- a/drivers/acpi/pptt.c >> +++ b/drivers/acpi/pptt.c >> @@ -298,6 +298,97 @@ static struct acpi_pptt_processor *acpi_find_processor_node(struct acpi_table_he >> return NULL; >> } >> >> +/** >> + * acpi_pptt_get_child_cpus() - Find all the CPUs below a PPTT processor node >> + * @table_hdr: A reference to the PPTT table. >> + * @parent_node: A pointer to the processor node in the @table_hdr. >> + * @cpus: A cpumask to fill with the CPUs below @parent_node. >> + * > Is this cpus mask always cleared before acpi_pptt_get_child_cpus() is called. > Just checking if it makes sense to clear it before we start the loop in this > function or do we have a need to start with a pre-filled cpumask ? It's only got one caller, which does the cpumask_clear() - but I've been bitten by this, so getting them both to do it would be least surprising. > Other than that, LGTM. > > Reviewed-by: Sudeep Holla <sudeep.holla@xxxxxxx> Thanks! James
