| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | /* |
| 3 | * Stack trace management functions |
| 4 | * |
| 5 | * Copyright IBM Corp. 2006 |
| 6 | * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com> |
| 7 | */ |
| 8 | |
| 9 | #include <linux/sched.h> |
| 10 | #include <linux/sched/debug.h> |
| 11 | #include <linux/stacktrace.h> |
| 12 | #include <linux/kallsyms.h> |
| 13 | #include <linux/export.h> |
| 14 | |
| 15 | static int __save_address(void *data, unsigned long address, int nosched) |
| 16 | { |
| 17 | struct stack_trace *trace = data; |
| 18 | |
| 19 | if (nosched && in_sched_functions(address)) |
| 20 | return 0; |
| 21 | if (trace->skip > 0) { |
| 22 | trace->skip--; |
| 23 | return 0; |
| 24 | } |
| 25 | if (trace->nr_entries < trace->max_entries) { |
| 26 | trace->entries[trace->nr_entries++] = address; |
| 27 | return 0; |
| 28 | } |
| 29 | return 1; |
| 30 | } |
| 31 | |
| 32 | static int save_address(void *data, unsigned long address, int reliable) |
| 33 | { |
| 34 | return __save_address(data, address, 0); |
| 35 | } |
| 36 | |
| 37 | static int save_address_nosched(void *data, unsigned long address, int reliable) |
| 38 | { |
| 39 | return __save_address(data, address, 1); |
| 40 | } |
| 41 | |
| 42 | void save_stack_trace(struct stack_trace *trace) |
| 43 | { |
| 44 | unsigned long sp; |
| 45 | |
| 46 | sp = current_stack_pointer(); |
| 47 | dump_trace(save_address, trace, NULL, sp); |
| 48 | if (trace->nr_entries < trace->max_entries) |
| 49 | trace->entries[trace->nr_entries++] = ULONG_MAX; |
| 50 | } |
| 51 | EXPORT_SYMBOL_GPL(save_stack_trace); |
| 52 | |
| 53 | void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) |
| 54 | { |
| 55 | unsigned long sp; |
| 56 | |
| 57 | sp = tsk->thread.ksp; |
| 58 | if (tsk == current) |
| 59 | sp = current_stack_pointer(); |
| 60 | dump_trace(save_address_nosched, trace, tsk, sp); |
| 61 | if (trace->nr_entries < trace->max_entries) |
| 62 | trace->entries[trace->nr_entries++] = ULONG_MAX; |
| 63 | } |
| 64 | EXPORT_SYMBOL_GPL(save_stack_trace_tsk); |
| 65 | |
| 66 | void save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace) |
| 67 | { |
| 68 | unsigned long sp; |
| 69 | |
| 70 | sp = kernel_stack_pointer(regs); |
| 71 | dump_trace(save_address, trace, NULL, sp); |
| 72 | if (trace->nr_entries < trace->max_entries) |
| 73 | trace->entries[trace->nr_entries++] = ULONG_MAX; |
| 74 | } |
| 75 | EXPORT_SYMBOL_GPL(save_stack_trace_regs); |