92 lines
1.9 KiB
C
92 lines
1.9 KiB
C
/**
|
|
* @file backtrace.c
|
|
*
|
|
* @remark Copyright 2002 OProfile authors
|
|
* @remark Read the file COPYING
|
|
*
|
|
* @author John Levon
|
|
* @author David Smith
|
|
*/
|
|
|
|
#include <linux/oprofile.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/mm.h>
|
|
#include <asm/ptrace.h>
|
|
#include <asm/uaccess.h>
|
|
#include <asm/stacktrace.h>
|
|
|
|
static void backtrace_warning_symbol(void *data, char *msg,
|
|
unsigned long symbol)
|
|
{
|
|
/* Ignore warnings */
|
|
}
|
|
|
|
static void backtrace_warning(void *data, char *msg)
|
|
{
|
|
/* Ignore warnings */
|
|
}
|
|
|
|
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 = {
|
|
.warning = backtrace_warning,
|
|
.warning_symbol = backtrace_warning_symbol,
|
|
.stack = backtrace_stack,
|
|
.address = backtrace_address,
|
|
};
|
|
|
|
struct frame_head {
|
|
struct frame_head *bp;
|
|
unsigned long ret;
|
|
} __attribute__((packed));
|
|
|
|
static struct frame_head *
|
|
dump_user_backtrace(struct frame_head * head)
|
|
{
|
|
struct frame_head bufhead[2];
|
|
|
|
/* Also check accessibility of one struct frame_head beyond */
|
|
if (!access_ok(VERIFY_READ, head, sizeof(bufhead)))
|
|
return NULL;
|
|
if (__copy_from_user_inatomic(bufhead, head, sizeof(bufhead)))
|
|
return NULL;
|
|
|
|
oprofile_add_trace(bufhead[0].ret);
|
|
|
|
/* frame pointers should strictly progress back up the stack
|
|
* (towards higher addresses) */
|
|
if (head >= bufhead[0].bp)
|
|
return NULL;
|
|
|
|
return bufhead[0].bp;
|
|
}
|
|
|
|
void
|
|
x86_backtrace(struct pt_regs * const regs, unsigned int depth)
|
|
{
|
|
struct frame_head *head = (struct frame_head *)frame_pointer(regs);
|
|
unsigned long stack = kernel_trap_sp(regs);
|
|
|
|
if (!user_mode_vm(regs)) {
|
|
if (depth)
|
|
dump_trace(NULL, regs, (unsigned long *)stack, 0,
|
|
&backtrace_ops, &depth);
|
|
return;
|
|
}
|
|
|
|
while (depth-- && head)
|
|
head = dump_user_backtrace(head);
|
|
}
|