aboutsummaryrefslogtreecommitdiffstats
path: root/arch/powerpc/kernel/stacktrace.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/powerpc/kernel/stacktrace.c')
-rw-r--r--arch/powerpc/kernel/stacktrace.c47
1 files changed, 47 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/stacktrace.c b/arch/powerpc/kernel/stacktrace.c
new file mode 100644
index 00000000000..e3638eeaaae
--- /dev/null
+++ b/arch/powerpc/kernel/stacktrace.c
@@ -0,0 +1,47 @@
1/*
2 * Stack trace utility
3 *
4 * Copyright 2008 Christoph Hellwig, IBM Corp.
5 *
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
11 */
12
13#include <linux/sched.h>
14#include <linux/stacktrace.h>
15#include <asm/ptrace.h>
16#include <asm/asm-offsets.h>
17
18/*
19 * Save stack-backtrace addresses into a stack_trace buffer.
20 */
21void save_stack_trace(struct stack_trace *trace)
22{
23 unsigned long sp;
24
25 asm("mr %0,1" : "=r" (sp));
26
27 for (;;) {
28 unsigned long *stack = (unsigned long *) sp;
29 unsigned long newsp, ip;
30
31 if (!validate_sp(sp, current, STACK_FRAME_OVERHEAD))
32 return;
33
34 newsp = stack[0];
35 ip = stack[STACK_FRAME_LR_SAVE];
36
37 if (!trace->skip)
38 trace->entries[trace->nr_entries++] = ip;
39 else
40 trace->skip--;
41
42 if (trace->nr_entries >= trace->max_entries)
43 return;
44
45 sp = newsp;
46 }
47}