| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 1 | /* |
| 2 | * arch/sh/kernel/stacktrace.c |
| 3 | * |
| 4 | * Stack trace management functions |
| 5 | * |
| 6 | * Copyright (C) 2006 - 2008 Paul Mundt |
| 7 | * |
| 8 | * This file is subject to the terms and conditions of the GNU General Public |
| 9 | * License. See the file "COPYING" in the main directory of this archive |
| 10 | * for more details. |
| 11 | */ |
| 12 | #include <linux/sched.h> |
| 13 | #include <linux/sched/debug.h> |
| 14 | #include <linux/stacktrace.h> |
| 15 | #include <linux/thread_info.h> |
| 16 | #include <linux/module.h> |
| 17 | #include <asm/unwinder.h> |
| 18 | #include <asm/ptrace.h> |
| 19 | #include <asm/stacktrace.h> |
| 20 | |
| 21 | static int save_stack_stack(void *data, char *name) |
| 22 | { |
| 23 | return 0; |
| 24 | } |
| 25 | |
| 26 | /* |
| 27 | * Save stack-backtrace addresses into a stack_trace buffer. |
| 28 | */ |
| 29 | static void save_stack_address(void *data, unsigned long addr, int reliable) |
| 30 | { |
| 31 | struct stack_trace *trace = data; |
| 32 | |
| 33 | if (!reliable) |
| 34 | return; |
| 35 | |
| 36 | if (trace->skip > 0) { |
| 37 | trace->skip--; |
| 38 | return; |
| 39 | } |
| 40 | |
| 41 | if (trace->nr_entries < trace->max_entries) |
| 42 | trace->entries[trace->nr_entries++] = addr; |
| 43 | } |
| 44 | |
| 45 | static const struct stacktrace_ops save_stack_ops = { |
| 46 | .stack = save_stack_stack, |
| 47 | .address = save_stack_address, |
| 48 | }; |
| 49 | |
| 50 | void save_stack_trace(struct stack_trace *trace) |
| 51 | { |
| 52 | unsigned long *sp = (unsigned long *)current_stack_pointer; |
| 53 | |
| 54 | unwind_stack(current, NULL, sp, &save_stack_ops, trace); |
| 55 | if (trace->nr_entries < trace->max_entries) |
| 56 | trace->entries[trace->nr_entries++] = ULONG_MAX; |
| 57 | } |
| 58 | EXPORT_SYMBOL_GPL(save_stack_trace); |
| 59 | |
| 60 | static void |
| 61 | save_stack_address_nosched(void *data, unsigned long addr, int reliable) |
| 62 | { |
| 63 | struct stack_trace *trace = (struct stack_trace *)data; |
| 64 | |
| 65 | if (!reliable) |
| 66 | return; |
| 67 | |
| 68 | if (in_sched_functions(addr)) |
| 69 | return; |
| 70 | |
| 71 | if (trace->skip > 0) { |
| 72 | trace->skip--; |
| 73 | return; |
| 74 | } |
| 75 | |
| 76 | if (trace->nr_entries < trace->max_entries) |
| 77 | trace->entries[trace->nr_entries++] = addr; |
| 78 | } |
| 79 | |
| 80 | static const struct stacktrace_ops save_stack_ops_nosched = { |
| 81 | .stack = save_stack_stack, |
| 82 | .address = save_stack_address_nosched, |
| 83 | }; |
| 84 | |
| 85 | void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) |
| 86 | { |
| 87 | unsigned long *sp = (unsigned long *)tsk->thread.sp; |
| 88 | |
| 89 | unwind_stack(current, NULL, sp, &save_stack_ops_nosched, trace); |
| 90 | if (trace->nr_entries < trace->max_entries) |
| 91 | trace->entries[trace->nr_entries++] = ULONG_MAX; |
| 92 | } |
| 93 | EXPORT_SYMBOL_GPL(save_stack_trace_tsk); |