x86_32: clean up play_dead

The removal of the CPU from the various maps was redundant as it already
happened in cpu_disable.

After cleaning this up, cpu_uninit only resets the tlb state, so rename
it and create a noop version for the X86_64 case (so the two play_deads
can be unified later).

Signed-off-by: Alex Nixon <alex.nixon@citrix.com>
Acked-by: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

2 files changed, 5 insertions, 18 deletions

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 80ab20d4fa39..18f5551b32dd 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -714,14 +714,10 @@ void __cpuinit cpu_init(void)
         mxcsr_feature_mask_init();
 }
 
-#ifdef CONFIG_HOTPLUG_CPU
-void __cpuinit cpu_uninit(void)
+void reset_lazy_tlbstate(void)
 {
         int cpu = raw_smp_processor_id();
-        cpu_clear(cpu, cpu_initialized);
 
-        /* lazy TLB state */
         per_cpu(cpu_tlbstate, cpu).state = 0;
         per_cpu(cpu_tlbstate, cpu).active_mm = &init_mm;
 }
-#endif
diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index e382fe0ccd66..d55eb49584b1 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -75,26 +75,17 @@ unsigned long thread_saved_pc(struct task_struct *tsk)
 #ifdef CONFIG_HOTPLUG_CPU
 #include <asm/nmi.h>
 
-static void cpu_exit_clear(void)
+/* We don't actually take CPU down, just spin without interrupts. */
+void native_play_dead(void)
 {
         int cpu = raw_smp_processor_id();
 
         idle_task_exit();
 
-        cpu_uninit();
-        irq_ctx_exit(cpu);
+        reset_lazy_tlbstate();
 
-        cpu_clear(cpu, cpu_callout_map);
-        cpu_clear(cpu, cpu_callin_map);
-
-        numa_remove_cpu(cpu);
-}
+        irq_ctx_exit(cpu);
 
-/* We don't actually take CPU down, just spin without interrupts. */
-void native_play_dead(void)
-{
-        /* This must be done before dead CPU ack */
-        cpu_exit_clear();
         mb();
         /* Ack it */
         __get_cpu_var(cpu_state) = CPU_DEAD;