[mirror_ubuntu-artful-kernel.git] / arch / avr32 / kernel / stacktrace.c

/*
 * Stack trace management functions
 *
 * Copyright (C) 2007 Atmel Corporation
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#include <linux/sched.h>
#include <linux/stacktrace.h>
#include <linux/thread_info.h>
#include <linux/module.h>

register unsigned long current_frame_pointer asm("r7");

struct stackframe {
	unsigned long lr;
	unsigned long fp;
};

/*
 * Save stack-backtrace addresses into a stack_trace buffer.
 */
void save_stack_trace(struct stack_trace *trace)
{
	unsigned long low, high;
	unsigned long fp;
	struct stackframe *frame;
	int skip = trace->skip;

	low = (unsigned long)task_stack_page(current);
	high = low + THREAD_SIZE;
	fp = current_frame_pointer;

	while (fp >= low && fp <= (high - 8)) {
		frame = (struct stackframe *)fp;

		if (skip) {
			skip--;
		} else {
			trace->entries[trace->nr_entries++] = frame->lr;
			if (trace->nr_entries >= trace->max_entries)
				break;
		}

		/*
		 * The next frame must be at a higher address than the
		 * current frame.
		 */
		low = fp + 8;
		fp = frame->fp;
	}
}
EXPORT_SYMBOL_GPL(save_stack_trace);
Commit	Line	Data
2f026037 HS	1	/*
	2	* Stack trace management functions
	3	*
	4	* Copyright (C) 2007 Atmel Corporation
	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 as
	8	* published by the Free Software Foundation.
	9	*/
	10	#include <linux/sched.h>
	11	#include <linux/stacktrace.h>
	12	#include <linux/thread_info.h>
8b95d917	13	#include <linux/module.h>
2f026037 HS	14
	15	register unsigned long current_frame_pointer asm("r7");
	16
	17	struct stackframe {
	18	unsigned long lr;
	19	unsigned long fp;
	20	};
	21
	22	/*
	23	* Save stack-backtrace addresses into a stack_trace buffer.
	24	*/
	25	void save_stack_trace(struct stack_trace *trace)
	26	{
	27	unsigned long low, high;
	28	unsigned long fp;
	29	struct stackframe *frame;
	30	int skip = trace->skip;
	31
	32	low = (unsigned long)task_stack_page(current);
	33	high = low + THREAD_SIZE;
	34	fp = current_frame_pointer;
	35
	36	while (fp >= low && fp <= (high - 8)) {
	37	frame = (struct stackframe *)fp;
	38
	39	if (skip) {
	40	skip--;
	41	} else {
	42	trace->entries[trace->nr_entries++] = frame->lr;
	43	if (trace->nr_entries >= trace->max_entries)
	44	break;
	45	}
	46
	47	/*
	48	* The next frame must be at a higher address than the
	49	* current frame.
	50	*/
	51	low = fp + 8;
	52	fp = frame->fp;
	53	}
	54	}
7b4c9505	55	EXPORT_SYMBOL_GPL(save_stack_trace);