[v2,5/8] NUMA Hotplug emulator

[Shaohui Zheng <shaohui.zheng@intel.com>]

>This looks like an incredibly painful interface. How about scrapping all
>of this _emu() mess and just reworking the register_cpu() interface?
> Something like:

hi, Paul
	I saw your reply on patchwork.kernel.org, but I did not find your email 
in my mailbox, you might forget to cc to me.

	I think that your register_cpu_node interface seems good, but this will 
remove the interface register_cpu. it is not the original purpose of the 
emulator, we want to emulate the oringal process, but we did not want to change
the old interface, that is a rule.

	I want to share some piece of codes, and I did not want to do so much change,
so I call register_cpu and register_cpu_emu in the same function. yes, it is a 
painful interface, I will add a function arch_register_cpu_emu to solve it.

Real hotplug process:
arch_register_cpu
	- call register_cpu

Emulated hotplug process:
arch_register_cpu_emu
	- call register_cpu_emu

diff --git a/arch/x86/kernel/topology.c b/arch/x86/kernel/topology.c
index 7e45159..93859d5 100644
--- a/arch/x86/kernel/topology.c
+++ b/arch/x86/kernel/topology.c
@@ -52,6 +52,16 @@ int __ref arch_register_cpu(int num)
 }
 EXPORT_SYMBOL(arch_register_cpu);
 
+/* emulated version for arch_register_cpu */
+int __ref arch_register_cpu_emu(int num, int nid)
+{
+	if (num)
+		per_cpu(cpu_devices, num).cpu.hotpluggable = 1;
+
+	return register_cpu_emu(&per_cpu(cpu_devices, num).cpu, nid);
+}
+EXPORT_SYMBOL(arch_register_cpu_emu);
+
 void arch_unregister_cpu(int num)
 {
 	unregister_cpu(&per_cpu(cpu_devices, num).cpu);

-- 
Thanks & Regards,
Shaohui