acrn-kernel/arch/blackfin/kernel/stacktrace.c

54 lines
1.1 KiB
C

/*
* Blackfin stacktrace code (mostly copied from avr32)
*
* Copyright 2009 Analog Devices Inc.
* Licensed under the GPL-2 or later.
*/
#include <linux/sched.h>
#include <linux/stacktrace.h>
#include <linux/thread_info.h>
#include <linux/module.h>
register unsigned long current_frame_pointer asm("FP");
struct stackframe {
unsigned long fp;
unsigned long rets;
};
/*
* 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 - sizeof(*frame))) {
frame = (struct stackframe *)fp;
if (skip) {
skip--;
} else {
trace->entries[trace->nr_entries++] = frame->rets;
if (trace->nr_entries >= trace->max_entries)
break;
}
/*
* The next frame must be at a higher address than the
* current frame.
*/
low = fp + sizeof(*frame);
fp = frame->fp;
}
}
EXPORT_SYMBOL_GPL(save_stack_trace);