From: James Morse <james.morse@arm.com> maillist inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I8T2RT Reference: https://git.kernel.org/pub/scm/linux/kernel/git/morse/linux.git/log/?h=mpam/... --------------------------- The ACPI table for MPAM describes a set of CPUs with the UID of a processor container. These exist both in the namespace and the PPTT. Using the existing for-each helpers, provide a helper to find the specified processor container in the PPTT, and fill a cpumask with the CPUs that belong to it. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Zeng Heng <zengheng4@huawei.com> --- drivers/acpi/pptt.c | 67 ++++++++++++++++++++++++++++++++++++++++++++ include/linux/acpi.h | 6 ++++ 2 files changed, 73 insertions(+) diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c index 6c1f668d63ba..9fbeed61cd87 100644 --- a/drivers/acpi/pptt.c +++ b/drivers/acpi/pptt.c @@ -295,6 +295,38 @@ static struct acpi_pptt_processor *acpi_find_processor_node(struct acpi_table_he return NULL; } +/* parent_node points into the table, but the table isn't provided. */ +static void acpi_pptt_get_child_cpus(struct acpi_pptt_processor *parent_node, + cpumask_t *cpus) +{ + struct acpi_pptt_processor *cpu_node; + struct acpi_table_header *table_hdr; + acpi_status status; + u32 acpi_id; + int cpu; + + status = acpi_get_table(ACPI_SIG_PPTT, 0, &table_hdr); + if (ACPI_FAILURE(status)) + return; + + for_each_possible_cpu(cpu) { + acpi_id = get_acpi_id_for_cpu(cpu); + cpu_node = acpi_find_processor_node(table_hdr, acpi_id); + + while (cpu_node) { + if (cpu_node == parent_node) { + cpumask_set_cpu(cpu, cpus); + break; + } + cpu_node = fetch_pptt_node(table_hdr, cpu_node->parent); + } + } + + acpi_put_table(table_hdr); + + return; +} + /** * acpi_pptt_for_each_container() - Iterate over all processor containers * @@ -351,6 +383,41 @@ int acpi_pptt_for_each_container(acpi_pptt_cpu_callback_t callback, void *arg) return ret; } +struct __cpus_from_container_arg { + u32 acpi_cpu_id; + cpumask_t *cpus; +}; + +static int __cpus_from_container(struct acpi_pptt_processor *container, void *arg) +{ + struct __cpus_from_container_arg *params = arg; + + if (container->acpi_processor_id == params->acpi_cpu_id) + acpi_pptt_get_child_cpus(container, params->cpus); + + return 0; +} + +/** + * acpi_pptt_get_cpus_from_container() - Populate a cpumask with all CPUs in a + * processor containers + * + * Find the specified Processor Container, and fill cpus with all the cpus + * below it. + * + * Return: 0 for a complete walk, or an error if the mask is incomplete. + */ +int acpi_pptt_get_cpus_from_container(u32 acpi_cpu_id, cpumask_t *cpus) +{ + struct __cpus_from_container_arg params; + + params.acpi_cpu_id = acpi_cpu_id; + params.cpus = cpus; + + cpumask_clear(cpus); + return acpi_pptt_for_each_container(&__cpus_from_container, ¶ms); +} + static u8 acpi_cache_type(enum cache_type type) { switch (type) { diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 7e4fc2f6883c..93b8155625bf 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -1496,6 +1496,7 @@ 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_cache_level_from_id(u32 cache_id); +int acpi_pptt_get_cpus_from_container(u32 acpi_cpu_id, cpumask_t *cpus); #else static inline int acpi_pptt_cpu_is_thread(unsigned int cpu) { @@ -1521,6 +1522,11 @@ static inline int find_acpi_cache_level_from_id(u32 cache_id) { return -EINVAL; } +static inline int acpi_pptt_get_cpus_from_container(u32 acpi_cpu_id, + cpumask_t *cpus) +{ + return -EINVAL; +} #endif #ifdef CONFIG_ARM64 -- 2.25.1