diff options
Diffstat (limited to 'arch/x86/kernel/smpboot.c')
| -rw-r--r-- | arch/x86/kernel/smpboot.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index c2f7d1d2a5c3..f02ecaf97904 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -80,6 +80,7 @@ #include <asm/intel-family.h> #include <asm/cpu_device_id.h> #include <asm/spec-ctrl.h> +#include <asm/hw_irq.h> /* representing HT siblings of each logical CPU */ DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_sibling_map); @@ -221,6 +222,11 @@ static void notrace start_secondary(void *unused) #ifdef CONFIG_X86_32 /* switch away from the initial page table */ load_cr3(swapper_pg_dir); + /* + * Initialize the CR4 shadow before doing anything that could + * try to read it. + */ + cr4_init_shadow(); __flush_tlb_all(); #endif load_current_idt(); @@ -266,6 +272,23 @@ static void notrace start_secondary(void *unused) } /** + * topology_is_primary_thread - Check whether CPU is the primary SMT thread + * @cpu: CPU to check + */ +bool topology_is_primary_thread(unsigned int cpu) +{ + return apic_id_is_primary_thread(per_cpu(x86_cpu_to_apicid, cpu)); +} + +/** + * topology_smt_supported - Check whether SMT is supported by the CPUs + */ +bool topology_smt_supported(void) +{ + return smp_num_siblings > 1; +} + +/** * topology_phys_to_logical_pkg - Map a physical package id to a logical * * Returns logical package id or -1 if not found |