#include <linux/module.h>
#include <linux/fs.h>
#include <linux/cpu.h>

static int __cpuinit my_cpu_callback(struct notifier_block *nfb,
    unsigned long action, void *hcpu)
{
    unsigned int cpu = (unsigned long)hcpu;

    switch (action) {
    case CPU_ONLINE:
    case CPU_ONLINE_FROZEN:
        printk("cpu 0x%x aktiviert\n", cpu);
        break;
    case CPU_DEAD:
    case CPU_DEAD_FROZEN:
        printk("cpu 0x%x deaktiviert\n", cpu);
        break;
    }
    return NOTIFY_OK;
}

static struct notifier_block my_cpu_notifier = {
    .notifier_call = my_cpu_callback;
};

static int __init mod_initialize(void)
{
    register_hotcpu_notifier(&my_cpu_notifier);
    printk("cpu_notifier angemeldet\n");
    return 0;
}

static void __exit mod_release(void)
{
    unregister_hotcpu_notifier(&my_cpu_notifier);
    printk("cpu_notifier abgemeldet\n");
}

module_init( mod_initialize );
module_exit( mod_release );
MODULE_LICENSE("GPL");