trunk/tests/markers/probe-direct.c

   1 /* probe.c
   2  *
   3  * Loads a function at a marker call site.
   4  *
   5  * (C) Copyright 2006 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
   6  *
   7  * This file is released under the GPLv2.
   8  * See the file COPYING for more details.
   9  */
  10
  11 #include <linux/marker.h>
  12 #include <linux/module.h>
  13 #include <linux/kallsyms.h>
  14 #include <linux/linkage.h>
  15
  16
  17 int value;
  18 void *ptr;
  19
  20 /* function to install */
  21 #define DO_MARK1_FORMAT "%d %p"
  22 asmlinkage void do_mark1(const char *format, int pavalue, void *paptr)
  23 {
  24         value = pavalue;
  25         ptr = paptr;
  26 }
  27
  28 int init_module(void)
  29 {
  30         int result;
  31         result = marker_set_probe("subsys_mark1", DO_MARK1_FORMAT,
  32                         (marker_probe_func*)do_mark1);
  33         if(!result) goto end;
  34
  35         return 0;
  36
  37 end:
  38         marker_remove_probe((marker_probe_func*)do_mark1);
  39         return -EPERM;
  40 }
  41
  42 void cleanup_module(void)
  43 {
  44         marker_remove_probe((marker_probe_func*)do_mark1);
  45 }
  46
  47 MODULE_LICENSE("GPL");
  48 MODULE_AUTHOR("Mathieu Desnoyers");
  49 MODULE_DESCRIPTION("Probe");