1 // SPDX-License-Identifier: GPL-2.0-only
3 * arch/arm/kernel/return_address.c
5 * Copyright (C) 2009 Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
8 #include <linux/export.h>
9 #include <linux/ftrace.h>
11 #if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND)
12 #include <linux/sched.h>
14 #include <asm/stacktrace.h>
16 struct return_address_data {
21 static int save_return_addr(struct stackframe *frame, void *d)
23 struct return_address_data *data = d;
26 data->addr = (void *)frame->pc;
35 void *return_address(unsigned int level)
37 struct return_address_data data;
38 struct stackframe frame;
40 data.level = level + 2;
43 frame.fp = (unsigned long)__builtin_frame_address(0);
44 frame.sp = current_stack_pointer;
45 frame.lr = (unsigned long)__builtin_return_address(0);
46 frame.pc = (unsigned long)return_address;
48 walk_stackframe(&frame, save_return_addr, &data);
56 #endif /* if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) */
58 EXPORT_SYMBOL_GPL(return_address);