dumpstack.c
/*
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs
* Copyright (C) 2009 Matt Fleming
* Copyright (C) 2002 - 2012 Paul Mundt
*
* 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.
*/
#include <linux/kallsyms.h>
#include <linux/ftrace.h>
#include <linux/debug_locks.h>
#include <linux/kdebug.h>
#include <linux/export.h>
#include <linux/uaccess.h>
#include <asm/unwinder.h>
#include <asm/stacktrace.h>
void dump_mem(const char *str, unsigned long bottom, unsigned long top)
{
unsigned long p;
int i;
printk("%s(0x%08lx to 0x%08lx)\n", str, bottom, top);
for (p = bottom & ~31; p < top; ) {
printk("%04lx: ", p & 0xffff);
for (i = 0; i < 8; i++, p += 4) {
unsigned int val;
if (p < bottom || p >= top)
printk(" ");
else {
if (__get_user(val, (unsigned int __user *)p)) {
printk("\n");
return;
}
printk("%08x ", val);
}
}
printk("\n");
}
}
void printk_address(unsigned long address, int reliable)
{
printk(" [<%p>] %s%pS\n", (void *) address,
reliable ? "" : "? ", (void *) address);
}
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
static void
print_ftrace_graph_addr(unsigned long addr, void *data,
const struct stacktrace_ops *ops,
struct thread_info *tinfo, int *graph)
{
struct task_struct *task = tinfo->task;
unsigned long ret_addr;
int index = task->curr_ret_stack;
if (addr != (unsigned long)return_to_handler)
return;
if (!task->ret_stack || index < *graph)
return;
index -= *graph;
ret_addr = task->ret_stack[index].ret;
ops->address(data, ret_addr, 1);
(*graph)++;
}
#else
static inline void
print_ftrace_graph_addr(unsigned long addr, void *data,
const struct stacktrace_ops *ops,
struct thread_info *tinfo, int *graph)
{ }
#endif
void
stack_reader_dump(struct task_struct *task, struct pt_regs *regs,
unsigned long *sp, const struct stacktrace_ops *ops,
void *data)
{
struct thread_info *context;
int graph = 0;
context = (struct thread_info *)
((unsigned long)sp & (~(THREAD_SIZE - 1)));
while (!kstack_end(sp)) {
unsigned long addr = *sp++;
if (__kernel_text_address(addr)) {
ops->address(data, addr, 1);
print_ftrace_graph_addr(addr, data, ops,
context, &graph);
}
}
}
static int print_trace_stack(void *data, char *name)
{
printk("%s <%s> ", (char *)data, name);
return 0;
}
/*
* Print one address/symbol entries per line.
*/
static void print_trace_address(void *data, unsigned long addr, int reliable)
{
printk(data);
printk_address(addr, reliable);
}
static const struct stacktrace_ops print_trace_ops = {
.stack = print_trace_stack,
.address = print_trace_address,
};
void show_trace(struct task_struct *tsk, unsigned long *sp,
struct pt_regs *regs)
{
if (regs && user_mode(regs))
return;
printk("\nCall trace:\n");
unwind_stack(tsk, regs, sp, &print_trace_ops, "");
printk("\n");
if (!tsk)
tsk = current;
debug_show_held_locks(tsk);
}
void show_stack(struct task_struct *tsk, unsigned long *sp)
{
unsigned long stack;
if (!tsk)
tsk = current;
if (tsk == current)
sp = (unsigned long *)current_stack_pointer;
else
sp = (unsigned long *)tsk->thread.sp;
stack = (unsigned long)sp;
dump_mem("Stack: ", stack, THREAD_SIZE +
(unsigned long)task_stack_page(tsk));
show_trace(tsk, sp, NULL);
}