projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| fd3e0bbc CH |
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 | ||
| 4b16f8e2 | 13 | #include <linux/export.h> |
| fd3e0bbc CH |
14 | #include <linux/sched.h> |
| 15 | #include <linux/stacktrace.h> | |
| 16 | #include <asm/ptrace.h> | |
| 01f4b8b8 | 17 | #include <asm/processor.h> |
| fd3e0bbc CH |
18 | |
| 19 | /* | |
| 20 | * Save stack-backtrace addresses into a stack_trace buffer. | |
| 21 | */ | |
| 01f4b8b8 AB |
22 | static void save_context_stack(struct stack_trace *trace, unsigned long sp, |
| 23 | struct task_struct *tsk, int savesched) | |
| fd3e0bbc | 24 | { |
| fd3e0bbc CH |
25 | for (;;) { |
| 26 | unsigned long *stack = (unsigned long *) sp; | |
| 27 | unsigned long newsp, ip; | |
| 28 | ||
| 01f4b8b8 | 29 | if (!validate_sp(sp, tsk, STACK_FRAME_OVERHEAD)) |
| fd3e0bbc CH |
30 | return; |
| 31 | ||
| 32 | newsp = stack[0]; | |
| 33 | ip = stack[STACK_FRAME_LR_SAVE]; | |
| 34 | ||
| 01f4b8b8 AB |
35 | if (savesched || !in_sched_functions(ip)) { |
| 36 | if (!trace->skip) | |
| 37 | trace->entries[trace->nr_entries++] = ip; | |
| 38 | else | |
| 39 | trace->skip--; | |
| 40 | } | |
| fd3e0bbc CH |
41 | |
| 42 | if (trace->nr_entries >= trace->max_entries) | |
| 43 | return; | |
| 44 | ||
| 45 | sp = newsp; | |
| 46 | } | |
| 47 | } | |
| 01f4b8b8 AB |
48 | |
| 49 | void save_stack_trace(struct stack_trace *trace) | |
| 50 | { | |
| 51 | unsigned long sp; | |
| 52 | ||
| acf620ec | 53 | sp = current_stack_pointer(); |
| 01f4b8b8 AB |
54 | |
| 55 | save_context_stack(trace, sp, current, 1); | |
| 56 | } | |
| 57 | EXPORT_SYMBOL_GPL(save_stack_trace); | |
| 58 | ||
| 59 | void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) | |
| 60 | { | |
| 6fdc9f50 | 61 | save_context_stack(trace, tsk->thread.ksp, tsk, 0); |
| 01f4b8b8 AB |
62 | } |
| 63 | EXPORT_SYMBOL_GPL(save_stack_trace_tsk); | |
| 35de3b1a SR |
64 | |
| 65 | void | |
| 66 | save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace) | |
| 67 | { | |
| 68 | save_context_stack(trace, regs->gpr[1], current, 0); | |
| 69 | } | |
| 70 | EXPORT_SYMBOL_GPL(save_stack_trace_regs); |