LXR linux/lib/cpu-notifier-error-inject.c

   1#include <linux/kernel.h>
   2#include <linux/cpu.h>
   3#include <linux/module.h>
   4#include <linux/notifier.h>
   5
   6static int priority;
   7static int cpu_up_prepare_error;
   8static int cpu_down_prepare_error;
   9
  10module_param(priority, int, 0);
  11MODULE_PARM_DESC(priority, "specify cpu notifier priority");
  12
  13module_param(cpu_up_prepare_error, int, 0644);
  14MODULE_PARM_DESC(cpu_up_prepare_error,
  15                "specify error code to inject CPU_UP_PREPARE action");
  16
  17module_param(cpu_down_prepare_error, int, 0644);
  18MODULE_PARM_DESC(cpu_down_prepare_error,
  19                "specify error code to inject CPU_DOWN_PREPARE action");
  20
  21static int err_inject_cpu_callback(struct notifier_block *nfb,
  22                                unsigned long action, void *hcpu)
  23{
  24        int err = 0;
  25
  26        switch (action) {
  27        case CPU_UP_PREPARE:
  28        case CPU_UP_PREPARE_FROZEN:
  29                err = cpu_up_prepare_error;
  30                break;
  31        case CPU_DOWN_PREPARE:
  32        case CPU_DOWN_PREPARE_FROZEN:
  33                err = cpu_down_prepare_error;
  34                break;
  35        }
  36        if (err)
  37                printk(KERN_INFO "Injecting error (%d) at cpu notifier\n", err);
  38
  39        return notifier_from_errno(err);
  40}
  41
  42static struct notifier_block err_inject_cpu_notifier = {
  43        .notifier_call = err_inject_cpu_callback,
  44};
  45
  46static int err_inject_init(void)
  47{
  48        err_inject_cpu_notifier.priority = priority;
  49
  50        return register_hotcpu_notifier(&err_inject_cpu_notifier);
  51}
  52
  53static void err_inject_exit(void)
  54{
  55        unregister_hotcpu_notifier(&err_inject_cpu_notifier);
  56}
  57
  58module_init(err_inject_init);
  59module_exit(err_inject_exit);
  60
  61MODULE_DESCRIPTION("CPU notifier error injection module");
  62MODULE_LICENSE("GPL");
  63MODULE_AUTHOR("Akinobu Mita <akinobu.mita@gmail.com>");
  64