Commit | Line | Data |
---|---|---|
4a089752 MD |
1 | /* |
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 | */ | |
16 | static 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 | ||
26 | static void probe_subsys_eventb(void) | |
27 | { | |
28 | printk(KERN_INFO "Event B is encountered\n"); | |
29 | } | |
30 | ||
7ec7fb39 | 31 | static int __init tp_sample_trace_init(void) |
4a089752 MD |
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 | ||
43 | module_init(tp_sample_trace_init); | |
44 | ||
7ec7fb39 | 45 | static void __exit tp_sample_trace_exit(void) |
4a089752 MD |
46 | { |
47 | unregister_trace_subsys_eventb(probe_subsys_eventb); | |
48 | unregister_trace_subsys_event(probe_subsys_event); | |
2504ea5e | 49 | tracepoint_synchronize_unregister(); |
4a089752 MD |
50 | } |
51 | ||
52 | module_exit(tp_sample_trace_exit); | |
53 | ||
54 | MODULE_LICENSE("GPL"); | |
55 | MODULE_AUTHOR("Mathieu Desnoyers"); | |
56 | MODULE_DESCRIPTION("Tracepoint Probes Samples"); |