arch/x86/kernel/stacktrace.c

   1 /*
   2  * Stack trace management functions
   3  *
   4  *  Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
   5  */
   6 #include <linux/sched.h>
   7 #include <linux/stacktrace.h>
   8 #include <linux/module.h>
   9 #include <asm/stacktrace.h>
  10
  11 static void save_stack_warning(void *data, char *msg)
  12 {
  13 }
  14
  15 static void
  16 save_stack_warning_symbol(void *data, char *msg, unsigned long symbol)
  17 {
  18 }
  19
  20 static int save_stack_stack(void *data, char *name)
  21 {
  22         return -1;
  23 }
  24
  25 static void save_stack_address(void *data, unsigned long addr)
  26 {
  27         struct stack_trace *trace = (struct stack_trace *)data;
  28         if (trace->skip > 0) {
  29                 trace->skip--;
  30                 return;
  31         }
  32         if (trace->nr_entries < trace->max_entries)
  33                 trace->entries[trace->nr_entries++] = addr;
  34 }
  35
  36 static const struct stacktrace_ops save_stack_ops = {
  37         .warning = save_stack_warning,
  38         .warning_symbol = save_stack_warning_symbol,
  39         .stack = save_stack_stack,
  40         .address = save_stack_address,
  41 };
  42
  43 /*
  44  * Save stack-backtrace addresses into a stack_trace buffer.
  45  */
  46 void save_stack_trace(struct stack_trace *trace)
  47 {
  48         dump_trace(current, NULL, NULL, &save_stack_ops, trace);
  49         if (trace->nr_entries < trace->max_entries)
  50                 trace->entries[trace->nr_entries++] = ULONG_MAX;
  51 }
  52 EXPORT_SYMBOL(save_stack_trace);