xref: /openbmc/linux/arch/x86/kernel/stacktrace.c (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
1 /*
2  * Stack trace management functions
3  *
4  *  Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
5  */
6 #include <linux/sched.h>
7 #include <linux/stacktrace.h>
8 #include <linux/module.h>
9 #include <asm/stacktrace.h>
10 
11 static void save_stack_warning(void *data, char *msg)
12 {
13 }
14 
15 static void
16 save_stack_warning_symbol(void *data, char *msg, unsigned long symbol)
17 {
18 }
19 
20 static int save_stack_stack(void *data, char *name)
21 {
22 	return -1;
23 }
24 
25 static void save_stack_address(void *data, unsigned long addr)
26 {
27 	struct stack_trace *trace = (struct stack_trace *)data;
28 	if (trace->skip > 0) {
29 		trace->skip--;
30 		return;
31 	}
32 	if (trace->nr_entries < trace->max_entries)
33 		trace->entries[trace->nr_entries++] = addr;
34 }
35 
36 static const struct stacktrace_ops save_stack_ops = {
37 	.warning = save_stack_warning,
38 	.warning_symbol = save_stack_warning_symbol,
39 	.stack = save_stack_stack,
40 	.address = save_stack_address,
41 };
42 
43 /*
44  * Save stack-backtrace addresses into a stack_trace buffer.
45  */
46 void save_stack_trace(struct stack_trace *trace)
47 {
48 	dump_trace(current, NULL, NULL, &save_stack_ops, trace);
49 	if (trace->nr_entries < trace->max_entries)
50 		trace->entries[trace->nr_entries++] = ULONG_MAX;
51 }
52 EXPORT_SYMBOL(save_stack_trace);
53