x86: move x86_64 gdt closer to i386

i386 and x86_64 used two different schemes for maintaining the gdt.
With this patch, x86_64 initial gdt table is defined in a .c file,
same way as i386 is now. Also, we call it "gdt_page", and the descriptor,
"early_gdt_descr". This way we achieve common naming, which can allow for
more code integration.

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

1 files changed, 3 insertions, 9 deletions

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index a71e3cad5470..fe2bd515d6cc 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -849,14 +849,8 @@ static int __cpuinit do_boot_cpu(int apicid, int cpu)
                 .done = COMPLETION_INITIALIZER_ONSTACK(c_idle.done),
         };
         INIT_WORK(&c_idle.work, do_fork_idle);
-#ifdef CONFIG_X86_64
-        /* allocate memory for gdts of secondary cpus. Hotplug is considered */
-        if (!cpu_gdt_descr[cpu].address &&
-                !(cpu_gdt_descr[cpu].address = get_zeroed_page(GFP_KERNEL))) {
-                printk(KERN_ERR "Failed to allocate GDT for CPU %d\n", cpu);
-                return -1;
-        }
 
+#ifdef CONFIG_X86_64
         /* Allocate node local memory for AP pdas */
         if (cpu > 0) {
                 boot_error = get_local_pda(cpu);
@@ -898,7 +892,6 @@ do_rest:
 #ifdef CONFIG_X86_32
         per_cpu(current_task, cpu) = c_idle.idle;
         init_gdt(cpu);
-        early_gdt_descr.address = (unsigned long)get_cpu_gdt_table(cpu);
         c_idle.idle->thread.ip = (unsigned long) start_secondary;
         /* Stack for startup_32 can be just as for start_secondary onwards */
         irq_ctx_init(cpu);
@@ -908,6 +901,7 @@ do_rest:
         initial_code = (unsigned long)start_secondary;
         clear_tsk_thread_flag(c_idle.idle, TIF_FORK);
 #endif
+        early_gdt_descr.address = (unsigned long)get_cpu_gdt_table(cpu);
         stack_start.sp = (void *) c_idle.idle->thread.sp;
 
         /* start_ip had better be page-aligned! */
@@ -1252,8 +1246,8 @@ void __init native_smp_prepare_boot_cpu(void)
         int me = smp_processor_id();
 #ifdef CONFIG_X86_32
         init_gdt(me);
-        switch_to_new_gdt();
 #endif
+        switch_to_new_gdt();
         /* already set me in cpu_online_map in boot_cpu_init() */
         cpu_set(me, cpu_callout_map);
         per_cpu(cpu_state, me) = CPU_ONLINE;