120 lines
2.3 KiB
C
120 lines
2.3 KiB
C
/*
|
|
* arch/xtensa/kernel/stacktrace.c
|
|
*
|
|
* This file is subject to the terms and conditions of the GNU General Public
|
|
* License. See the file "COPYING" in the main directory of this archive
|
|
* for more details.
|
|
*
|
|
* Copyright (C) 2001 - 2013 Tensilica Inc.
|
|
*/
|
|
#include <linux/export.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/stacktrace.h>
|
|
|
|
#include <asm/stacktrace.h>
|
|
#include <asm/traps.h>
|
|
|
|
void walk_stackframe(unsigned long *sp,
|
|
int (*fn)(struct stackframe *frame, void *data),
|
|
void *data)
|
|
{
|
|
unsigned long a0, a1;
|
|
unsigned long sp_end;
|
|
|
|
a1 = (unsigned long)sp;
|
|
sp_end = ALIGN(a1, THREAD_SIZE);
|
|
|
|
spill_registers();
|
|
|
|
while (a1 < sp_end) {
|
|
struct stackframe frame;
|
|
|
|
sp = (unsigned long *)a1;
|
|
|
|
a0 = *(sp - 4);
|
|
a1 = *(sp - 3);
|
|
|
|
if (a1 <= (unsigned long)sp)
|
|
break;
|
|
|
|
frame.pc = MAKE_PC_FROM_RA(a0, a1);
|
|
frame.sp = a1;
|
|
|
|
if (fn(&frame, data))
|
|
return;
|
|
}
|
|
}
|
|
|
|
#ifdef CONFIG_STACKTRACE
|
|
|
|
struct stack_trace_data {
|
|
struct stack_trace *trace;
|
|
unsigned skip;
|
|
};
|
|
|
|
static int stack_trace_cb(struct stackframe *frame, void *data)
|
|
{
|
|
struct stack_trace_data *trace_data = data;
|
|
struct stack_trace *trace = trace_data->trace;
|
|
|
|
if (trace_data->skip) {
|
|
--trace_data->skip;
|
|
return 0;
|
|
}
|
|
if (!kernel_text_address(frame->pc))
|
|
return 0;
|
|
|
|
trace->entries[trace->nr_entries++] = frame->pc;
|
|
return trace->nr_entries >= trace->max_entries;
|
|
}
|
|
|
|
void save_stack_trace_tsk(struct task_struct *task, struct stack_trace *trace)
|
|
{
|
|
struct stack_trace_data trace_data = {
|
|
.trace = trace,
|
|
.skip = trace->skip,
|
|
};
|
|
walk_stackframe(stack_pointer(task), stack_trace_cb, &trace_data);
|
|
}
|
|
EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
|
|
|
|
void save_stack_trace(struct stack_trace *trace)
|
|
{
|
|
save_stack_trace_tsk(current, trace);
|
|
}
|
|
EXPORT_SYMBOL_GPL(save_stack_trace);
|
|
|
|
#endif
|
|
|
|
#ifdef CONFIG_FRAME_POINTER
|
|
|
|
struct return_addr_data {
|
|
unsigned long addr;
|
|
unsigned skip;
|
|
};
|
|
|
|
static int return_address_cb(struct stackframe *frame, void *data)
|
|
{
|
|
struct return_addr_data *r = data;
|
|
|
|
if (r->skip) {
|
|
--r->skip;
|
|
return 0;
|
|
}
|
|
if (!kernel_text_address(frame->pc))
|
|
return 0;
|
|
r->addr = frame->pc;
|
|
return 1;
|
|
}
|
|
|
|
unsigned long return_address(unsigned level)
|
|
{
|
|
struct return_addr_data r = {
|
|
.skip = level + 1,
|
|
};
|
|
walk_stackframe(stack_pointer(NULL), return_address_cb, &r);
|
|
return r.addr;
|
|
}
|
|
EXPORT_SYMBOL(return_address);
|
|
|
|
#endif
|