[patch v2 29/30] x86/cpu/topology: Provide __num_[cores|threads]_per_package

From: Thomas Gleixner
Date: Tue Jan 23 2024 - 08:24:45 EST


From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

Expose properly accounted information and accessors so the fiddling with
other topology variables can be replaced.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>



---
arch/x86/include/asm/topology.h | 12 ++++++++++++
arch/x86/kernel/cpu/common.c | 6 ++++++
arch/x86/kernel/cpu/topology.c | 8 +++++++-
3 files changed, 25 insertions(+), 1 deletion(-)
---
--- a/arch/x86/include/asm/topology.h
+++ b/arch/x86/include/asm/topology.h
@@ -146,6 +146,8 @@ extern const struct cpumask *cpu_cluster
extern unsigned int __max_dies_per_package;
extern unsigned int __max_logical_packages;
extern unsigned int __max_threads_per_core;
+extern unsigned int __num_threads_per_package;
+extern unsigned int __num_cores_per_package;

static inline unsigned int topology_max_packages(void)
{
@@ -157,6 +159,16 @@ static inline unsigned int topology_max_
return __max_dies_per_package;
}

+static inline unsigned int topology_num_cores_per_package(void)
+{
+ return __num_cores_per_package;
+}
+
+static inline unsigned int topology_num_threads_per_package(void)
+{
+ return __num_threads_per_package;
+}
+
#ifdef CONFIG_X86_LOCAL_APIC
int topology_get_logical_id(u32 apicid, enum x86_topology_domains at_level);
#else
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -81,6 +81,12 @@ EXPORT_SYMBOL(__max_dies_per_package);
unsigned int __max_logical_packages __ro_after_init = 1;
EXPORT_SYMBOL(__max_logical_packages);

+unsigned int __num_cores_per_package __ro_after_init = 1;
+EXPORT_SYMBOL(__num_cores_per_package);
+
+unsigned int __num_threads_per_package __ro_after_init = 1;
+EXPORT_SYMBOL(__num_threads_per_package);
+
static struct ppin_info {
int feature;
int msr_ppin_ctl;
--- a/arch/x86/kernel/cpu/topology.c
+++ b/arch/x86/kernel/cpu/topology.c
@@ -386,7 +386,7 @@ void __init topology_init_possible_cpus(
unsigned int disabled = topo_info.nr_disabled_cpus;
unsigned int cnta, cntb, cpu, allowed = 1;
unsigned int total = assigned + disabled;
- u32 apicid;
+ u32 apicid, firstid;

if (!restrict_to_up()) {
if (WARN_ON_ONCE(assigned > nr_cpu_ids)) {
@@ -422,6 +422,12 @@ void __init topology_init_possible_cpus(
__max_threads_per_core = 1U << (get_count_order(cntb) - get_count_order(cnta));
pr_info("Max. threads per core: %3u\n", __max_threads_per_core);

+ firstid = find_first_bit(apic_maps[TOPO_SMT_DOMAIN].map, MAX_LOCAL_APIC);
+ __num_cores_per_package = topology_unit_count(firstid, TOPO_CORE_DOMAIN, TOPO_PKG_DOMAIN);
+ pr_info("Num. cores per package: %3u\n", __num_cores_per_package);
+ __num_threads_per_package = topology_unit_count(firstid, TOPO_SMT_DOMAIN, TOPO_PKG_DOMAIN);
+ pr_info("Num. threads per package: %3u\n", __num_threads_per_package);
+
pr_info("Allowing %u present CPUs plus %u hotplug CPUs\n", assigned, disabled);
if (topo_info.nr_rejected_cpus)
pr_info("Rejected CPUs %u\n", topo_info.nr_rejected_cpus);