x86: merge smp_prepare_boot_cpu

it is practically the same between arches now, so it is
moved to smpboot.c. Minor differences (gdt initialization)
live inside an ifdef

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

arch/x86/kernel/smpboot.c

@@ -24,6 +24,9 @@
 #include <mach_wakecpu.h>
 #include <smpboot_hooks.h>
 
+/* State of each CPU */
+DEFINE_PER_CPU(int, cpu_state) = { 0 };
+
 /* Store all idle threads, this can be reused instead of creating
 * a new thread. Also avoids complicated thread destroy functionality
 * for idle threads.
@@ -999,6 +1002,21 @@ int __cpuinit native_cpu_up(unsigned int cpu)
 	return 0;
 }
 
+/*
+ * Early setup to make printk work.
+ */
+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
+	/* already set me in cpu_online_map in boot_cpu_init() */
+	cpu_set(me, cpu_callout_map);
+	per_cpu(cpu_state, me) = CPU_ONLINE;
+}
+
 #ifdef CONFIG_HOTPLUG_CPU
 void remove_siblinginfo(int cpu)
 {

arch/x86/kernel/smpboot_32.c

@@ -77,9 +77,6 @@ u8 apicid_2_node[MAX_APICID];
 extern void map_cpu_to_logical_apicid(void);
 extern void unmap_cpu_to_logical_apicid(int cpu);
 
-/* State of each CPU. */
-DEFINE_PER_CPU(int, cpu_state) = { 0 };
-
 #ifdef CONFIG_HOTPLUG_CPU
 void cpu_exit_clear(void)
 {
@@ -219,17 +216,6 @@ void __init native_smp_prepare_cpus(unsigned int max_cpus)
 	smp_boot_cpus(max_cpus);
 }
 
-void __init native_smp_prepare_boot_cpu(void)
-{
-	unsigned int cpu = smp_processor_id();
-
-	init_gdt(cpu);
-	switch_to_new_gdt();
-
-	cpu_set(cpu, cpu_callout_map);
-	__get_cpu_var(cpu_state) = CPU_ONLINE;
-}
-
 extern void impress_friends(void);
 extern void smp_checks(void);
 

arch/x86/kernel/smpboot_64.c

@@ -68,9 +68,6 @@
 /* Set when the idlers are all forked */
 int smp_threads_ready;
 
-/* State of each CPU */
-DEFINE_PER_CPU(int, cpu_state) = { 0 };
-
 cycles_t cacheflush_time;
 unsigned long cache_decay_ticks;
 
@@ -216,17 +213,6 @@ void __init native_smp_prepare_cpus(unsigned int max_cpus)
 	print_cpu_info(&cpu_data(0));
 }
 
-/*
- * Early setup to make printk work.
- */
-void __init native_smp_prepare_boot_cpu(void)
-{
-	int me = smp_processor_id();
-	/* already set me in cpu_online_map in boot_cpu_init() */
-	cpu_set(me, cpu_callout_map);
-	per_cpu(cpu_state, me) = CPU_ONLINE;
-}
-
 extern void impress_friends(void);
 extern void smp_checks(void);