1/*
2 * Simple stack backtrace regression test module
3 *
4 * (C) Copyright 2008 Intel Corporation
5 * Author: Arjan van de Ven <arjan@linux.intel.com>
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; version 2
10 * of the License.
11 */
12
13#include <linux/completion.h>
14#include <linux/delay.h>
15#include <linux/interrupt.h>
16#include <linux/module.h>
17#include <linux/sched.h>
18#include <linux/stacktrace.h>
19
20static void backtrace_test_normal(void)
21{
22 pr_info("Testing a backtrace from process context.\n");
23 pr_info("The following trace is a kernel self test and not a bug!\n");
24
25 dump_stack();
26}
27
28static DECLARE_COMPLETION(backtrace_work);
29
30static void backtrace_test_irq_callback(unsigned long data)
31{
32 dump_stack();
33 complete(&backtrace_work);
34}
35
36static DECLARE_TASKLET(backtrace_tasklet, &backtrace_test_irq_callback, 0);
37
38static void backtrace_test_irq(void)
39{
40 pr_info("Testing a backtrace from irq context.\n");
41 pr_info("The following trace is a kernel self test and not a bug!\n");
42
43 init_completion(&backtrace_work);
44 tasklet_schedule(&backtrace_tasklet);
45 wait_for_completion(&backtrace_work);
46}
47
48#ifdef CONFIG_STACKTRACE
49static void backtrace_test_saved(void)
50{
51 struct stack_trace trace;
52 unsigned long entries[8];
53
54 pr_info("Testing a saved backtrace.\n");
55 pr_info("The following trace is a kernel self test and not a bug!\n");
56
57 trace.nr_entries = 0;
58 trace.max_entries = ARRAY_SIZE(entries);
59 trace.entries = entries;
60 trace.skip = 0;
61
62 save_stack_trace(&trace);
63 print_stack_trace(&trace, 0);
64}
65#else
66static void backtrace_test_saved(void)
67{
68 pr_info("Saved backtrace test skipped.\n");
69}
70#endif
71
72static int backtrace_regression_test(void)
73{
74 pr_info("====[ backtrace testing ]===========\n");
75
76 backtrace_test_normal();
77 backtrace_test_irq();
78 backtrace_test_saved();
79
80 pr_info("====[ end of backtrace testing ]====\n");
81 return 0;
82}
83
84static void exitf(void)
85{
86}
87
88module_init(backtrace_regression_test);
89module_exit(exitf);
90MODULE_LICENSE("GPL");
91MODULE_AUTHOR("Arjan van de Ven <arjan@linux.intel.com>");
92