| 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"); |