Atsushi Nemoto | 1df0f0f | 2006-09-26 23:44:01 +0900 | [diff] [blame] | 1 | /* |
| 2 | * arch/mips/kernel/stacktrace.c |
| 3 | * |
| 4 | * Stack trace management functions |
| 5 | * |
| 6 | * Copyright (C) 2006 Atsushi Nemoto <anemo@mba.ocn.ne.jp> |
| 7 | */ |
| 8 | #include <linux/sched.h> |
| 9 | #include <linux/stacktrace.h> |
| 10 | #include <asm/stacktrace.h> |
| 11 | |
| 12 | /* |
| 13 | * Save stack-backtrace addresses into a stack_trace buffer: |
| 14 | */ |
| 15 | static void save_raw_context_stack(struct stack_trace *trace, |
Atsushi Nemoto | 2312669 | 2006-09-28 19:15:33 +0900 | [diff] [blame] | 16 | unsigned long reg29) |
Atsushi Nemoto | 1df0f0f | 2006-09-26 23:44:01 +0900 | [diff] [blame] | 17 | { |
| 18 | unsigned long *sp = (unsigned long *)reg29; |
| 19 | unsigned long addr; |
| 20 | |
| 21 | while (!kstack_end(sp)) { |
| 22 | addr = *sp++; |
| 23 | if (__kernel_text_address(addr)) { |
Atsushi Nemoto | 2312669 | 2006-09-28 19:15:33 +0900 | [diff] [blame] | 24 | if (trace->skip > 0) |
| 25 | trace->skip--; |
Atsushi Nemoto | 1df0f0f | 2006-09-26 23:44:01 +0900 | [diff] [blame] | 26 | else |
Atsushi Nemoto | 2312669 | 2006-09-28 19:15:33 +0900 | [diff] [blame] | 27 | trace->entries[trace->nr_entries++] = addr; |
Atsushi Nemoto | 1df0f0f | 2006-09-26 23:44:01 +0900 | [diff] [blame] | 28 | if (trace->nr_entries >= trace->max_entries) |
| 29 | break; |
| 30 | } |
| 31 | } |
| 32 | } |
| 33 | |
Atsushi Nemoto | 1924600 | 2006-09-29 18:02:51 +0900 | [diff] [blame] | 34 | static void save_context_stack(struct stack_trace *trace, |
Atsushi Nemoto | 2312669 | 2006-09-28 19:15:33 +0900 | [diff] [blame] | 35 | struct task_struct *task, struct pt_regs *regs) |
Atsushi Nemoto | 1df0f0f | 2006-09-26 23:44:01 +0900 | [diff] [blame] | 36 | { |
| 37 | unsigned long sp = regs->regs[29]; |
| 38 | #ifdef CONFIG_KALLSYMS |
| 39 | unsigned long ra = regs->regs[31]; |
| 40 | unsigned long pc = regs->cp0_epc; |
Atsushi Nemoto | 1df0f0f | 2006-09-26 23:44:01 +0900 | [diff] [blame] | 41 | |
| 42 | if (raw_show_trace || !__kernel_text_address(pc)) { |
Atsushi Nemoto | 1924600 | 2006-09-29 18:02:51 +0900 | [diff] [blame] | 43 | unsigned long stack_page = |
| 44 | (unsigned long)task_stack_page(task); |
Atsushi Nemoto | 2312669 | 2006-09-28 19:15:33 +0900 | [diff] [blame] | 45 | if (stack_page && sp >= stack_page && |
| 46 | sp <= stack_page + THREAD_SIZE - 32) |
| 47 | save_raw_context_stack(trace, sp); |
Atsushi Nemoto | 1924600 | 2006-09-29 18:02:51 +0900 | [diff] [blame] | 48 | return; |
Atsushi Nemoto | 1df0f0f | 2006-09-26 23:44:01 +0900 | [diff] [blame] | 49 | } |
| 50 | do { |
Atsushi Nemoto | 2312669 | 2006-09-28 19:15:33 +0900 | [diff] [blame] | 51 | if (trace->skip > 0) |
| 52 | trace->skip--; |
Atsushi Nemoto | 1df0f0f | 2006-09-26 23:44:01 +0900 | [diff] [blame] | 53 | else |
Atsushi Nemoto | 2312669 | 2006-09-28 19:15:33 +0900 | [diff] [blame] | 54 | trace->entries[trace->nr_entries++] = pc; |
Atsushi Nemoto | 1df0f0f | 2006-09-26 23:44:01 +0900 | [diff] [blame] | 55 | if (trace->nr_entries >= trace->max_entries) |
| 56 | break; |
Atsushi Nemoto | 1924600 | 2006-09-29 18:02:51 +0900 | [diff] [blame] | 57 | pc = unwind_stack(task, &sp, pc, &ra); |
Atsushi Nemoto | 1df0f0f | 2006-09-26 23:44:01 +0900 | [diff] [blame] | 58 | } while (pc); |
| 59 | #else |
Atsushi Nemoto | eea32d4 | 2006-10-16 22:48:49 +0900 | [diff] [blame] | 60 | save_raw_context_stack(trace, sp); |
Atsushi Nemoto | 1df0f0f | 2006-09-26 23:44:01 +0900 | [diff] [blame] | 61 | #endif |
Atsushi Nemoto | 1df0f0f | 2006-09-26 23:44:01 +0900 | [diff] [blame] | 62 | } |
| 63 | |
| 64 | /* |
| 65 | * Save stack-backtrace addresses into a stack_trace buffer. |
Atsushi Nemoto | 1df0f0f | 2006-09-26 23:44:01 +0900 | [diff] [blame] | 66 | */ |
Atsushi Nemoto | 2312669 | 2006-09-28 19:15:33 +0900 | [diff] [blame] | 67 | void save_stack_trace(struct stack_trace *trace, struct task_struct *task) |
Atsushi Nemoto | 1df0f0f | 2006-09-26 23:44:01 +0900 | [diff] [blame] | 68 | { |
| 69 | struct pt_regs dummyregs; |
| 70 | struct pt_regs *regs = &dummyregs; |
| 71 | |
| 72 | WARN_ON(trace->nr_entries || !trace->max_entries); |
| 73 | |
| 74 | if (task && task != current) { |
| 75 | regs->regs[29] = task->thread.reg29; |
| 76 | regs->regs[31] = 0; |
| 77 | regs->cp0_epc = task->thread.reg31; |
| 78 | } else { |
| 79 | if (!task) |
| 80 | task = current; |
| 81 | prepare_frametrace(regs); |
| 82 | } |
| 83 | |
Atsushi Nemoto | 1924600 | 2006-09-29 18:02:51 +0900 | [diff] [blame] | 84 | save_context_stack(trace, task, regs); |
Atsushi Nemoto | 1df0f0f | 2006-09-26 23:44:01 +0900 | [diff] [blame] | 85 | } |