diff options
Diffstat (limited to 'samples/tracepoints/tracepoint-probe-sample.c')
-rw-r--r-- | samples/tracepoints/tracepoint-probe-sample.c | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/samples/tracepoints/tracepoint-probe-sample.c b/samples/tracepoints/tracepoint-probe-sample.c new file mode 100644 index 000000000000..55abfdda4bd4 --- /dev/null +++ b/samples/tracepoints/tracepoint-probe-sample.c | |||
@@ -0,0 +1,55 @@ | |||
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 | |||
31 | int __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 | |||
43 | module_init(tp_sample_trace_init); | ||
44 | |||
45 | void __exit tp_sample_trace_exit(void) | ||
46 | { | ||
47 | unregister_trace_subsys_eventb(probe_subsys_eventb); | ||
48 | unregister_trace_subsys_event(probe_subsys_event); | ||
49 | } | ||
50 | |||
51 | module_exit(tp_sample_trace_exit); | ||
52 | |||
53 | MODULE_LICENSE("GPL"); | ||
54 | MODULE_AUTHOR("Mathieu Desnoyers"); | ||
55 | MODULE_DESCRIPTION("Tracepoint Probes Samples"); | ||