simplify the stacktrace code
[linux-3.10.git] / arch / x86_64 / kernel / stacktrace.c
1 /*
2  * arch/x86_64/kernel/stacktrace.c
3  *
4  * Stack trace management functions
5  *
6  *  Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
7  */
8 #include <linux/sched.h>
9 #include <linux/stacktrace.h>
10 #include <linux/module.h>
11 #include <asm/stacktrace.h>
12
13 static void save_stack_warning(void *data, char *msg)
14 {
15 }
16
17 static void
18 save_stack_warning_symbol(void *data, char *msg, unsigned long symbol)
19 {
20 }
21
22 static int save_stack_stack(void *data, char *name)
23 {
24         return -1;
25 }
26
27 static void save_stack_address(void *data, unsigned long addr)
28 {
29         struct stack_trace *trace = (struct stack_trace *)data;
30         if (trace->skip > 0) {
31                 trace->skip--;
32                 return;
33         }
34         if (trace->nr_entries < trace->max_entries)
35                 trace->entries[trace->nr_entries++] = addr;
36 }
37
38 static struct stacktrace_ops save_stack_ops = {
39         .warning = save_stack_warning,
40         .warning_symbol = save_stack_warning_symbol,
41         .stack = save_stack_stack,
42         .address = save_stack_address,
43 };
44
45 /*
46  * Save stack-backtrace addresses into a stack_trace buffer.
47  */
48 void save_stack_trace(struct stack_trace *trace)
49 {
50         dump_trace(current, NULL, NULL, &save_stack_ops, trace);
51         if (trace->nr_entries < trace->max_entries)
52                 trace->entries[trace->nr_entries++] = ULONG_MAX;
53 }
54 EXPORT_SYMBOL(save_stack_trace);