92 lines
2.1 KiB
C
Executable file
92 lines
2.1 KiB
C
Executable file
/*
|
|
* SH specific backtracing code for oprofile
|
|
*
|
|
* Copyright 2007 STMicroelectronics Ltd.
|
|
*
|
|
* Author: Dave Peverley <dpeverley@mpc-data.co.uk>
|
|
*
|
|
* Based on ARM oprofile backtrace code by Richard Purdie and in turn, i386
|
|
* oprofile backtrace code by John Levon, David Smith
|
|
*
|
|
* 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/oprofile.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/kallsyms.h>
|
|
#include <linux/mm.h>
|
|
#include <asm/unwinder.h>
|
|
#include <asm/ptrace.h>
|
|
#include <linux/uaccess.h>
|
|
#include <asm/sections.h>
|
|
#include <asm/stacktrace.h>
|
|
|
|
static int backtrace_stack(void *data, char *name)
|
|
{
|
|
/* Yes, we want all stacks */
|
|
return 0;
|
|
}
|
|
|
|
static void backtrace_address(void *data, unsigned long addr, int reliable)
|
|
{
|
|
unsigned int *depth = data;
|
|
|
|
if ((*depth)--)
|
|
oprofile_add_trace(addr);
|
|
}
|
|
|
|
static struct stacktrace_ops backtrace_ops = {
|
|
.stack = backtrace_stack,
|
|
.address = backtrace_address,
|
|
};
|
|
|
|
/* Limit to stop backtracing too far. */
|
|
static int backtrace_limit = 20;
|
|
|
|
static unsigned long *
|
|
user_backtrace(unsigned long *stackaddr, struct pt_regs *regs)
|
|
{
|
|
unsigned long buf_stack;
|
|
|
|
/* Also check accessibility of address */
|
|
if (!access_ok(VERIFY_READ, stackaddr, sizeof(unsigned long)))
|
|
return NULL;
|
|
|
|
if (__copy_from_user_inatomic(&buf_stack, stackaddr, sizeof(unsigned long)))
|
|
return NULL;
|
|
|
|
/* Quick paranoia check */
|
|
if (buf_stack & 3)
|
|
return NULL;
|
|
|
|
oprofile_add_trace(buf_stack);
|
|
|
|
stackaddr++;
|
|
|
|
return stackaddr;
|
|
}
|
|
|
|
void sh_backtrace(struct pt_regs * const regs, unsigned int depth)
|
|
{
|
|
unsigned long *stackaddr;
|
|
|
|
/*
|
|
* Paranoia - clip max depth as we could get lost in the weeds.
|
|
*/
|
|
if (depth > backtrace_limit)
|
|
depth = backtrace_limit;
|
|
|
|
stackaddr = (unsigned long *)kernel_stack_pointer(regs);
|
|
if (!user_mode(regs)) {
|
|
if (depth)
|
|
unwind_stack(NULL, regs, stackaddr,
|
|
&backtrace_ops, &depth);
|
|
return;
|
|
}
|
|
|
|
while (depth-- && (stackaddr != NULL))
|
|
stackaddr = user_backtrace(stackaddr, regs);
|
|
}
|