diff options
Diffstat (limited to 'arch/x86/kernel/cpu')
| -rw-r--r-- | arch/x86/kernel/cpu/topology.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/topology.c b/arch/x86/kernel/cpu/topology.c index e35ccdc84910..6073a16628f9 100644 --- a/arch/x86/kernel/cpu/topology.c +++ b/arch/x86/kernel/cpu/topology.c @@ -372,6 +372,19 @@ unsigned int topology_unit_count(u32 apicid, enum x86_topology_domains which_uni return topo_unit_count(lvlid, at_level, apic_maps[which_units].map); } +#ifdef CONFIG_SMP +int topology_get_primary_thread(unsigned int cpu) +{ + u32 apic_id = cpuid_to_apicid[cpu]; + + /* + * Get the core domain level APIC id, which is the primary thread + * and return the CPU number assigned to it. + */ + return topo_lookup_cpuid(topo_apicid(apic_id, TOPO_CORE_DOMAIN)); +} +#endif + #ifdef CONFIG_ACPI_HOTPLUG_CPU /** * topology_hotplug_apic - Handle a physical hotplugged APIC after boot |