LXR linux/kernel/stacktrace.c

   1/*
   2 * kernel/stacktrace.c
   3 *
   4 * Stack trace management functions
   5 *
   6 *  Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
   7 */
   8#include <linux/sched.h>
   9#include <linux/kernel.h>
  10#include <linux/export.h>
  11#include <linux/kallsyms.h>
  12#include <linux/stacktrace.h>
  13
  14void print_stack_trace(struct stack_trace *trace, int spaces)
  15{
  16        int i;
  17
  18        if (WARN_ON(!trace->entries))
  19                return;
  20
  21        for (i = 0; i < trace->nr_entries; i++)
  22                printk("%*c%pS\n", 1 + spaces, ' ', (void *)trace->entries[i]);
  23}
  24EXPORT_SYMBOL_GPL(print_stack_trace);
  25
  26int snprint_stack_trace(char *buf, size_t size,
  27                        struct stack_trace *trace, int spaces)
  28{
  29        int i;
  30        int generated;
  31        int total = 0;
  32
  33        if (WARN_ON(!trace->entries))
  34                return 0;
  35
  36        for (i = 0; i < trace->nr_entries; i++) {
  37                generated = snprintf(buf, size, "%*c%pS\n", 1 + spaces, ' ',
  38                                     (void *)trace->entries[i]);
  39
  40                total += generated;
  41
  42                /* Assume that generated isn't a negative number */
  43                if (generated >= size) {
  44                        buf += size;
  45                        size = 0;
  46                } else {
  47                        buf += generated;
  48                        size -= generated;
  49                }
  50        }
  51
  52        return total;
  53}
  54EXPORT_SYMBOL_GPL(snprint_stack_trace);
  55
  56/*
  57 * Architectures that do not implement save_stack_trace_*()
  58 * get these weak aliases and once-per-bootup warnings
  59 * (whenever this facility is utilized - for example by procfs):
  60 */
  61__weak void
  62save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
  63{
  64        WARN_ONCE(1, KERN_INFO "save_stack_trace_tsk() not implemented yet.\n");
  65}
  66
  67__weak void
  68save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace)
  69{
  70        WARN_ONCE(1, KERN_INFO "save_stack_trace_regs() not implemented yet.\n");
  71}
  72
  73__weak int
  74save_stack_trace_tsk_reliable(struct task_struct *tsk,
  75                              struct stack_trace *trace)
  76{
  77        WARN_ONCE(1, KERN_INFO "save_stack_tsk_reliable() not implemented yet.\n");
  78        return -ENOSYS;
  79}
  80