2 * arch/arm64/kernel/return_address.c
4 * Copyright (C) 2013 Linaro Limited
5 * Author: AKASHI Takahiro <takahiro.akashi@linaro.org>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
12 #include <linux/export.h>
13 #include <linux/ftrace.h>
14 #include <linux/kprobes.h>
16 #include <asm/stack_pointer.h>
17 #include <asm/stacktrace.h>
19 struct return_address_data {
24 static int save_return_addr(struct stackframe *frame, void *d)
26 struct return_address_data *data = d;
29 data->addr = (void *)frame->pc;
36 NOKPROBE_SYMBOL(save_return_addr);
38 void *return_address(unsigned int level)
40 struct return_address_data data;
41 struct stackframe frame;
43 data.level = level + 2;
46 frame.fp = (unsigned long)__builtin_frame_address(0);
47 frame.pc = (unsigned long)return_address; /* dummy */
48 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
49 frame.graph = current->curr_ret_stack;
52 walk_stackframe(current, &frame, save_return_addr, &data);
59 EXPORT_SYMBOL_GPL(return_address);
60 NOKPROBE_SYMBOL(return_address);