xref: /linux/arch/x86/kernel/stacktrace.c (revision ed3174d93c342b8b2eeba6bbd124707d55304a7b)
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, int reliable)
26 {
27 	struct stack_trace *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 void
37 save_stack_address_nosched(void *data, unsigned long addr, int reliable)
38 {
39 	struct stack_trace *trace = (struct stack_trace *)data;
40 	if (in_sched_functions(addr))
41 		return;
42 	if (trace->skip > 0) {
43 		trace->skip--;
44 		return;
45 	}
46 	if (trace->nr_entries < trace->max_entries)
47 		trace->entries[trace->nr_entries++] = addr;
48 }
49 
50 static const struct stacktrace_ops save_stack_ops = {
51 	.warning = save_stack_warning,
52 	.warning_symbol = save_stack_warning_symbol,
53 	.stack = save_stack_stack,
54 	.address = save_stack_address,
55 };
56 
57 static const struct stacktrace_ops save_stack_ops_nosched = {
58 	.warning = save_stack_warning,
59 	.warning_symbol = save_stack_warning_symbol,
60 	.stack = save_stack_stack,
61 	.address = save_stack_address_nosched,
62 };
63 
64 /*
65  * Save stack-backtrace addresses into a stack_trace buffer.
66  */
67 void save_stack_trace(struct stack_trace *trace)
68 {
69 	dump_trace(current, NULL, NULL, 0, &save_stack_ops, trace);
70 	if (trace->nr_entries < trace->max_entries)
71 		trace->entries[trace->nr_entries++] = ULONG_MAX;
72 }
73 
74 void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
75 {
76 	dump_trace(tsk, NULL, NULL, 0, &save_stack_ops_nosched, trace);
77 	if (trace->nr_entries < trace->max_entries)
78 		trace->entries[trace->nr_entries++] = ULONG_MAX;
79 }
80