mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-18 17:54:13 +08:00
2d7c11bfc9
This patch changes the walk_stacktrace and its callers for easier integration of stack unwinding. The arch/arm/kernel/stacktrace.h file is also moved to arch/arm/include/asm/stacktrace.h. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
84 lines
2.0 KiB
C
84 lines
2.0 KiB
C
/*
|
|
* Arm specific backtracing code for oprofile
|
|
*
|
|
* Copyright 2005 Openedhand Ltd.
|
|
*
|
|
* Author: Richard Purdie <rpurdie@openedhand.com>
|
|
*
|
|
* Based on 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/mm.h>
|
|
#include <linux/uaccess.h>
|
|
#include <asm/ptrace.h>
|
|
#include <asm/stacktrace.h>
|
|
|
|
static int report_trace(struct stackframe *frame, void *d)
|
|
{
|
|
unsigned int *depth = d;
|
|
|
|
if (*depth) {
|
|
oprofile_add_trace(frame->pc);
|
|
(*depth)--;
|
|
}
|
|
|
|
return *depth == 0;
|
|
}
|
|
|
|
/*
|
|
* The registers we're interested in are at the end of the variable
|
|
* length saved register structure. The fp points at the end of this
|
|
* structure so the address of this struct is:
|
|
* (struct frame_tail *)(xxx->fp)-1
|
|
*/
|
|
struct frame_tail {
|
|
struct frame_tail *fp;
|
|
unsigned long sp;
|
|
unsigned long lr;
|
|
} __attribute__((packed));
|
|
|
|
static struct frame_tail* user_backtrace(struct frame_tail *tail)
|
|
{
|
|
struct frame_tail buftail[2];
|
|
|
|
/* Also check accessibility of one struct frame_tail beyond */
|
|
if (!access_ok(VERIFY_READ, tail, sizeof(buftail)))
|
|
return NULL;
|
|
if (__copy_from_user_inatomic(buftail, tail, sizeof(buftail)))
|
|
return NULL;
|
|
|
|
oprofile_add_trace(buftail[0].lr);
|
|
|
|
/* frame pointers should strictly progress back up the stack
|
|
* (towards higher addresses) */
|
|
if (tail >= buftail[0].fp)
|
|
return NULL;
|
|
|
|
return buftail[0].fp-1;
|
|
}
|
|
|
|
void arm_backtrace(struct pt_regs * const regs, unsigned int depth)
|
|
{
|
|
struct frame_tail *tail = ((struct frame_tail *) regs->ARM_fp) - 1;
|
|
|
|
if (!user_mode(regs)) {
|
|
struct stackframe frame;
|
|
frame.fp = regs->ARM_fp;
|
|
frame.sp = regs->ARM_sp;
|
|
frame.lr = regs->ARM_lr;
|
|
frame.pc = regs->ARM_pc;
|
|
walk_stackframe(&frame, report_trace, &depth);
|
|
return;
|
|
}
|
|
|
|
while (depth-- && tail && !((unsigned long) tail & 3))
|
|
tail = user_backtrace(tail);
|
|
}
|