1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * Simple stack backtrace regression test module 4 * 5 * (C) Copyright 2008 Intel Corporation 6 * Author: Arjan van de Ven <arjan@linux.intel.com> 7 */ 8 9#include <linux/completion.h> 10#include <linux/delay.h> 11#include <linux/interrupt.h> 12#include <linux/module.h> 13#include <linux/sched.h> 14#include <linux/stacktrace.h> 15 16static void backtrace_test_normal(void) 17{ 18 pr_info("Testing a backtrace from process context.\n"); 19 pr_info("The following trace is a kernel self test and not a bug!\n"); 20 21 dump_stack(); 22} 23 24static void backtrace_test_bh_workfn(struct work_struct *work) 25{ 26 dump_stack(); 27} 28 29static DECLARE_WORK(backtrace_bh_work, &backtrace_test_bh_workfn); 30 31static void backtrace_test_bh(void) 32{ 33 pr_info("Testing a backtrace from BH context.\n"); 34 pr_info("The following trace is a kernel self test and not a bug!\n"); 35 36 queue_work(system_bh_wq, &backtrace_bh_work); 37 flush_work(&backtrace_bh_work); 38} 39 40#ifdef CONFIG_STACKTRACE 41static void backtrace_test_saved(void) 42{ 43 unsigned long entries[8]; 44 unsigned int nr_entries; 45 46 pr_info("Testing a saved backtrace.\n"); 47 pr_info("The following trace is a kernel self test and not a bug!\n"); 48 49 nr_entries = stack_trace_save(entries, ARRAY_SIZE(entries), 0); 50 stack_trace_print(entries, nr_entries, 0); 51} 52#else 53static void backtrace_test_saved(void) 54{ 55 pr_info("Saved backtrace test skipped.\n"); 56} 57#endif 58 59static int backtrace_regression_test(void) 60{ 61 pr_info("====[ backtrace testing ]===========\n"); 62 63 backtrace_test_normal(); 64 backtrace_test_bh(); 65 backtrace_test_saved(); 66 67 pr_info("====[ end of backtrace testing ]====\n"); 68 return 0; 69} 70 71static void exitf(void) 72{ 73} 74 75module_init(backtrace_regression_test); 76module_exit(exitf); 77MODULE_LICENSE("GPL"); 78MODULE_AUTHOR("Arjan van de Ven <arjan@linux.intel.com>"); 79