| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Stack trace utility for OpenRISC |
| 3 | * |
| 4 | * Copyright (C) 2017 Stafford Horne <shorne@gmail.com> |
| 5 | * |
| 6 | * This file is licensed under the terms of the GNU General Public License |
| 7 | * version 2. This program is licensed "as is" without any warranty of any |
| 8 | * kind, whether express or implied. |
| 9 | * |
| 10 | * Losely based on work from sh and powerpc. |
| 11 | */ |
| 12 | |
| 13 | #include <linux/export.h> |
| 14 | #include <linux/sched.h> |
| 15 | #include <linux/sched/debug.h> |
| 16 | #include <linux/stacktrace.h> |
| 17 | |
| 18 | #include <asm/processor.h> |
| 19 | #include <asm/unwinder.h> |
| 20 | |
| 21 | /* |
| 22 | * Save stack-backtrace addresses into a stack_trace buffer. |
| 23 | */ |
| 24 | static void |
| 25 | save_stack_address(void *data, unsigned long addr, int reliable) |
| 26 | { |
| 27 | struct stack_trace *trace = data; |
| 28 | |
| 29 | if (!reliable) |
| 30 | return; |
| 31 | |
| 32 | if (trace->skip > 0) { |
| 33 | trace->skip--; |
| 34 | return; |
| 35 | } |
| 36 | |
| 37 | if (trace->nr_entries < trace->max_entries) |
| 38 | trace->entries[trace->nr_entries++] = addr; |
| 39 | } |
| 40 | |
| 41 | void save_stack_trace(struct stack_trace *trace) |
| 42 | { |
| 43 | unwind_stack(trace, (unsigned long *) &trace, save_stack_address); |
| 44 | } |
| 45 | EXPORT_SYMBOL_GPL(save_stack_trace); |
| 46 | |
| 47 | static void |
| 48 | save_stack_address_nosched(void *data, unsigned long addr, int reliable) |
| 49 | { |
| 50 | struct stack_trace *trace = (struct stack_trace *)data; |
| 51 | |
| 52 | if (!reliable) |
| 53 | return; |
| 54 | |
| 55 | if (in_sched_functions(addr)) |
| 56 | return; |
| 57 | |
| 58 | if (trace->skip > 0) { |
| 59 | trace->skip--; |
| 60 | return; |
| 61 | } |
| 62 | |
| 63 | if (trace->nr_entries < trace->max_entries) |
| 64 | trace->entries[trace->nr_entries++] = addr; |
| 65 | } |
| 66 | |
| 67 | void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) |
| 68 | { |
| 69 | unsigned long *sp = NULL; |
| 70 | |
| 71 | if (tsk == current) |
| 72 | sp = (unsigned long *) &sp; |
| 73 | else |
| 74 | sp = (unsigned long *) KSTK_ESP(tsk); |
| 75 | |
| 76 | unwind_stack(trace, sp, save_stack_address_nosched); |
| 77 | } |
| 78 | EXPORT_SYMBOL_GPL(save_stack_trace_tsk); |
| 79 | |
| 80 | void |
| 81 | save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace) |
| 82 | { |
| 83 | unwind_stack(trace, (unsigned long *) regs->sp, |
| 84 | save_stack_address_nosched); |
| 85 | } |
| 86 | EXPORT_SYMBOL_GPL(save_stack_trace_regs); |