Support for hot-pluggable CPUs

modulename: hotplug.ko

and/or

hotplug-cpu.ko

and/or

cpu_hotplug.ko

configname: CONFIG_HOTPLUG_CPU

Linux Kernel Configuration
└─>Processor type and features
└─>Support for hot-pluggable CPUs
In linux kernel since version 2.6.12  
Say Y here to allow turning CPUs off and on. CPUs can be
controlled through /sys/devices/system/cpu.
( Note: power management support will enable this option
automatically on SMP systems. )
Say N if you want to disable CPU hotplug.

depends
CONFIG_SMP