kernel/watchdogtest.c

   1 /*
   2  * Simple softlockup watchdog regression test module
   3  *
   4  * Copyright (C) 2012 Motorola Mobility LLC.
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; version 2
   9  * of the License.
  10  */
  11
  12 #include <linux/completion.h>
  13 #include <linux/workqueue.h>
  14 #include <linux/irq.h>
  15 #include <linux/preempt.h>
  16 #include <linux/module.h>
  17 #include <linux/debugfs.h>
  18
  19 struct completion wdt_timeout_complete;
  20 static void wdt_timeout_work(struct work_struct *work)
  21 {
  22         local_irq_disable();
  23         while (1)
  24         ;
  25         local_irq_enable();
  26         complete(&wdt_timeout_complete);
  27 }
  28 static DECLARE_WORK(wdt_timeout_work_struct, wdt_timeout_work);
  29
  30 static int fire_watchdog_reset_set(void *data, u64 val)
  31 {
  32
  33         printk(KERN_WARNING "Fire hardware watchdog reset.\n");
  34         printk(KERN_WARNING "Please wait ...\n");
  35         init_completion(&wdt_timeout_complete);
  36         schedule_work_on(0, &wdt_timeout_work_struct);
  37         wait_for_completion(&wdt_timeout_complete);
  38         return 0;
  39 }
  40 DEFINE_SIMPLE_ATTRIBUTE(fire_watchdog_reset_fops,
  41         NULL, fire_watchdog_reset_set, "%llu\n");
  42
  43 static int fire_softlockup_reset_set(void *data, u64 val)
  44 {
  45         printk(KERN_WARNING "Fire softlockup watchdog reset.\n");
  46         printk(KERN_WARNING "Please wait ...\n");
  47         preempt_disable();
  48         while (1)
  49         ;
  50
  51         return 0;
  52 }
  53 DEFINE_SIMPLE_ATTRIBUTE(fire_softlockup_reset_fops,
  54         NULL, fire_softlockup_reset_set, "%llu\n");
  55
  56 static int watchdog_test_init(void)
  57 {
  58         debugfs_create_file("fire_softlockup_reset", 0200,
  59                 NULL, NULL, &fire_softlockup_reset_fops);
  60         debugfs_create_file("fire_watchdog_reset", 0200,
  61                 NULL, NULL, &fire_watchdog_reset_fops);
  62         return 0;
  63 }
  64
  65 static void watchdog_test_exit(void)
  66 {
  67 }
  68
  69 module_init(watchdog_test_init);
  70 module_exit(watchdog_test_exit);
  71 MODULE_LICENSE("GPL");