Commit 05df0bc5 authored by Yu Liao's avatar Yu Liao Committed by openeuler-sync-bot
Browse files

ACPI / PPTT: Find PPTT processor node by cache id 

openeuler inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I77UDW


CVE: NA

--------------------------------

The MPAM table identifies caches by id, but the driver also wants to know
the processor node.

Add a helper that walks every possible cache, until it finds the one
identified by id, then return processor node.

Signed-off-by: default avatarYu Liao <liaoyu15@huawei.com>
(cherry picked from commit 534ad2fc)
parent a60c622d

drivers/acpi/pptt.c

+55 −0
Original line number Diff line number Diff line
@@ -958,3 +958,58 @@ int __init acpi_pptt_init(void) 


	return 0;

}



struct acpi_pptt_processor *find_acpi_processor_node_from_cache_id(u32 cache_id)

{

	u32 acpi_cpu_id;

	acpi_status status;

	int level, cpu, num_levels;

	struct acpi_pptt_cache *cache;

	struct acpi_table_header *table;

	struct acpi_pptt_cache_v1 *cache_v1;

	struct acpi_pptt_processor *cpu_node;



	status = acpi_get_table(ACPI_SIG_PPTT, 0, &table);

	if (ACPI_FAILURE(status)) {

		acpi_pptt_warn_missing();

		return NULL;

	}



	if (table->revision < 3) {

		acpi_put_table(table);

		return NULL;

	}



	/*

	 * If we found the cache first, we'd still need to walk from each CPU

	 * to find the level...

	 */

	for_each_possible_cpu(cpu) {

		acpi_cpu_id = get_acpi_id_for_cpu(cpu);

		cpu_node = acpi_find_processor_node(table, acpi_cpu_id);

		if (!cpu_node)

			break;

		num_levels = acpi_count_levels(table, cpu_node);



		for (level = 0; level <= num_levels; level++) {

			cache = acpi_find_cache_node(table, acpi_cpu_id,

						     ACPI_PPTT_CACHE_TYPE_UNIFIED,

						     level, &cpu_node);

			if (!cache)

				continue;



			cache_v1 = ACPI_ADD_PTR(struct acpi_pptt_cache_v1,

						cache,

						sizeof(struct acpi_pptt_cache));



			if (cache->flags & ACPI_PPTT_CACHE_ID_VALID &&

			    cache_v1->cache_id == cache_id) {

				acpi_put_table(table);

				return cpu_node;

			}

		}

	}



	acpi_put_table(table);

	return NULL;

}

include/linux/acpi.h

+5 −0
Original line number Diff line number Diff line
@@ -1367,6 +1367,7 @@ int find_acpi_cpu_topology_cluster(unsigned int cpu); 
int find_acpi_cpu_topology_package(unsigned int cpu);

int find_acpi_cpu_topology_hetero_id(unsigned int cpu);

int find_acpi_cpu_cache_topology(unsigned int cpu, int level);

struct acpi_pptt_processor *find_acpi_processor_node_from_cache_id(u32 cache_id);

#else

static inline int acpi_pptt_cpu_is_thread(unsigned int cpu)

{
@@ -1392,6 +1393,10 @@ static inline int find_acpi_cpu_cache_topology(unsigned int cpu, int level) 
{

	return -EINVAL;

}

static inline struct acpi_pptt_processor *find_acpi_processor_node_from_cache_id(u32 cache_id)

{

	return NULL;

}

#endif



#ifdef CONFIG_ACPI