1/*
2 * 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/kernel.h>
10#include <linux/export.h>
11#include <linux/kallsyms.h>
12#include <linux/stacktrace.h>
13
14void print_stack_trace(struct stack_trace *trace, int spaces)
15{
16 int i;
17
18 if (WARN_ON(!trace->entries))
19 return;
20
21 for (i = 0; i < trace->nr_entries; i++)
22 printk("%*c%pS\n", 1 + spaces, ' ', (void *)trace->entries[i]);
23}
24EXPORT_SYMBOL_GPL(print_stack_trace);
25
26int snprint_stack_trace(char *buf, size_t size,
27 struct stack_trace *trace, int spaces)
28{
29 int i;
30 int generated;
31 int total = 0;
32
33 if (WARN_ON(!trace->entries))
34 return 0;
35
36 for (i = 0; i < trace->nr_entries; i++) {
37 generated = snprintf(buf, size, "%*c%pS\n", 1 + spaces, ' ',
38 (void *)trace->entries[i]);
39
40 total += generated;
41
42 /* Assume that generated isn't a negative number */
43 if (generated >= size) {
44 buf += size;
45 size = 0;
46 } else {
47 buf += generated;
48 size -= generated;
49 }
50 }
51
52 return total;
53}
54EXPORT_SYMBOL_GPL(snprint_stack_trace);
55
56/*
57 * Architectures that do not implement save_stack_trace_*()
58 * get these weak aliases and once-per-bootup warnings
59 * (whenever this facility is utilized - for example by procfs):
60 */
61__weak void
62save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
63{
64 WARN_ONCE(1, KERN_INFO "save_stack_trace_tsk() not implemented yet.\n");
65}
66
67__weak void
68save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace)
69{
70 WARN_ONCE(1, KERN_INFO "save_stack_trace_regs() not implemented yet.\n");
71}
72
73__weak int
74save_stack_trace_tsk_reliable(struct task_struct *tsk,
75 struct stack_trace *trace)
76{
77 WARN_ONCE(1, KERN_INFO "save_stack_tsk_reliable() not implemented yet.\n");
78 return -ENOSYS;
79}
80