x86: use specialized routine for setup per-cpu area

We use the same routing as x86_64, moved now to setup.c.
Just with a few ifdefs inside.
Note that this routing uses prefill_possible_map().
It has the very nice side effect of allowing hotplugging of
cpus that are marked as present but disabled by acpi bios.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 2 insertions, 0 deletions

diff --git a/arch/x86/kernel/smpboot_32.c b/arch/x86/kernel/smpboot_32.c
index 92a5df6190b5..bf5c9e9f26c1 100644
--- a/arch/x86/kernel/smpboot_32.c
+++ b/arch/x86/kernel/smpboot_32.c
@@ -665,6 +665,7 @@ static int __cpuinit do_boot_cpu(int apicid, int cpu)
                 unmap_cpu_to_logical_apicid(cpu);
                 cpu_clear(cpu, cpu_callout_map); /* was set here (do_boot_cpu()) */
                 cpu_clear(cpu, cpu_initialized); /* was set by cpu_init() */
+                cpu_clear(cpu, cpu_possible_map);
                 cpucount--;
         } else {
                 per_cpu(x86_cpu_to_apicid, cpu) = apicid;
@@ -743,6 +744,7 @@ EXPORT_SYMBOL(xquad_portio);
 
 static void __init disable_smp(void)
 {
+        cpu_possible_map = cpumask_of_cpu(0);
         smpboot_clear_io_apic_irqs();
         phys_cpu_present_map = physid_mask_of_physid(0);
         map_cpu_to_logical_apicid();