blob: e3a964889dc7951565b3f45497e0e123762ebab5 [file] [log] [blame]
Mathieu Desnoyers4a089752008-07-18 12:16:16 -04001/*
2 * tracepoint-probe-sample.c
3 *
4 * sample tracepoint probes.
5 */
6
7#include <linux/module.h>
8#include <linux/file.h>
9#include <linux/dcache.h>
10#include "tp-samples-trace.h"
11
12/*
13 * Here the caller only guarantees locking for struct file and struct inode.
14 * Locking must therefore be done in the probe to use the dentry.
15 */
16static void probe_subsys_event(struct inode *inode, struct file *file)
17{
18 path_get(&file->f_path);
19 dget(file->f_path.dentry);
20 printk(KERN_INFO "Event is encountered with filename %s\n",
21 file->f_path.dentry->d_name.name);
22 dput(file->f_path.dentry);
23 path_put(&file->f_path);
24}
25
26static void probe_subsys_eventb(void)
27{
28 printk(KERN_INFO "Event B is encountered\n");
29}
30
31int __init tp_sample_trace_init(void)
32{
33 int ret;
34
35 ret = register_trace_subsys_event(probe_subsys_event);
36 WARN_ON(ret);
37 ret = register_trace_subsys_eventb(probe_subsys_eventb);
38 WARN_ON(ret);
39
40 return 0;
41}
42
43module_init(tp_sample_trace_init);
44
45void __exit tp_sample_trace_exit(void)
46{
47 unregister_trace_subsys_eventb(probe_subsys_eventb);
48 unregister_trace_subsys_event(probe_subsys_event);
Mathieu Desnoyers2504ea52008-11-14 17:47:41 -050049 tracepoint_synchronize_unregister();
Mathieu Desnoyers4a089752008-07-18 12:16:16 -040050}
51
52module_exit(tp_sample_trace_exit);
53
54MODULE_LICENSE("GPL");
55MODULE_AUTHOR("Mathieu Desnoyers");
56MODULE_DESCRIPTION("Tracepoint Probes Samples");