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 */ 16static void probe_subsys_event(void *ignore, 17 struct inode *inode, struct file *file) 18{ 19 path_get(&file->f_path); 20 dget(file->f_path.dentry); 21 printk(KERN_INFO "Event is encountered with filename %s\n", 22 file->f_path.dentry->d_name.name); 23 dput(file->f_path.dentry); 24 path_put(&file->f_path); 25} 26 27static void probe_subsys_eventb(void *ignore) 28{ 29 printk(KERN_INFO "Event B is encountered\n"); 30} 31 32static int __init tp_sample_trace_init(void) 33{ 34 int ret; 35 36 ret = register_trace_subsys_event(probe_subsys_event, NULL); 37 WARN_ON(ret); 38 ret = register_trace_subsys_eventb(probe_subsys_eventb, NULL); 39 WARN_ON(ret); 40 41 return 0; 42} 43 44module_init(tp_sample_trace_init); 45 46static void __exit tp_sample_trace_exit(void) 47{ 48 unregister_trace_subsys_eventb(probe_subsys_eventb, NULL); 49 unregister_trace_subsys_event(probe_subsys_event, NULL); 50 tracepoint_synchronize_unregister(); 51} 52 53module_exit(tp_sample_trace_exit); 54 55MODULE_LICENSE("GPL"); 56MODULE_AUTHOR("Mathieu Desnoyers"); 57MODULE_DESCRIPTION("Tracepoint Probes Samples"); 58