1/*
 2 * Stacktrace support for Hexagon
 3 *
 4 * Copyright (c) 2010-2011, The Linux Foundation. All rights reserved.
 5 *
 6 * This program is free software; you can redistribute it and/or modify
 7 * it under the terms of the GNU General Public License version 2 and
 8 * only version 2 as published by the Free Software Foundation.
 9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
18 * 02110-1301, USA.
19 */
20
21#include <linux/sched.h>
22#include <linux/sched/task_stack.h>
23#include <linux/stacktrace.h>
24#include <linux/thread_info.h>
25#include <linux/module.h>
26
27register unsigned long current_frame_pointer asm("r30");
28
29struct stackframe {
30	unsigned long fp;
31	unsigned long rets;
32};
33
34/*
35 * Save stack-backtrace addresses into a stack_trace buffer.
36 */
37void save_stack_trace(struct stack_trace *trace)
38{
39	unsigned long low, high;
40	unsigned long fp;
41	struct stackframe *frame;
42	int skip = trace->skip;
43
44	low = (unsigned long)task_stack_page(current);
45	high = low + THREAD_SIZE;
46	fp = current_frame_pointer;
47
48	while (fp >= low && fp <= (high - sizeof(*frame))) {
49		frame = (struct stackframe *)fp;
50
51		if (skip) {
52			skip--;
53		} else {
54			trace->entries[trace->nr_entries++] = frame->rets;
55			if (trace->nr_entries >= trace->max_entries)
56				break;
57		}
58
59		/*
60		 * The next frame must be at a higher address than the
61		 * current frame.
62		 */
63		low = fp + sizeof(*frame);
64		fp = frame->fp;
65	}
66}
67EXPORT_SYMBOL_GPL(save_stack_trace);

 1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 * Stacktrace support for Hexagon
 4 *
 5 * Copyright (c) 2010-2011, The Linux Foundation. All rights reserved.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 6 */
 7
 8#include <linux/sched.h>
 9#include <linux/sched/task_stack.h>
10#include <linux/stacktrace.h>
11#include <linux/thread_info.h>
12#include <linux/module.h>
13
 
 
14struct stackframe {
15	unsigned long fp;
16	unsigned long rets;
17};
18
19/*
20 * Save stack-backtrace addresses into a stack_trace buffer.
21 */
22void save_stack_trace(struct stack_trace *trace)
23{
24	unsigned long low, high;
25	unsigned long fp;
26	struct stackframe *frame;
27	int skip = trace->skip;
28
29	low = (unsigned long)task_stack_page(current);
30	high = low + THREAD_SIZE;
31	fp = (unsigned long)__builtin_frame_address(0);
32
33	while (fp >= low && fp <= (high - sizeof(*frame))) {
34		frame = (struct stackframe *)fp;
35
36		if (skip) {
37			skip--;
38		} else {
39			trace->entries[trace->nr_entries++] = frame->rets;
40			if (trace->nr_entries >= trace->max_entries)
41				break;
42		}
43
44		/*
45		 * The next frame must be at a higher address than the
46		 * current frame.
47		 */
48		low = fp + sizeof(*frame);
49		fp = frame->fp;
50	}
51}
52EXPORT_SYMBOL_GPL(save_stack_trace);