samples/tracepoints/tracepoint-probe-sample2.c

   1 /*
   2  * tracepoint-probe-sample2.c
   3  *
   4  * 2nd sample tracepoint probes.
   5  */
   6
   7 #include <linux/module.h>
   8 #include <linux/fs.h>
   9 #include "tp-samples-trace.h"
  10
  11 /*
  12  * Here the caller only guarantees locking for struct file and struct inode.
  13  * Locking must therefore be done in the probe to use the dentry.
  14  */
  15 static void probe_subsys_event(struct inode *inode, struct file *file)
  16 {
  17         printk(KERN_INFO "Event is encountered with inode number %lu\n",
  18                 inode->i_ino);
  19 }
  20
  21 static int __init tp_sample_trace_init(void)
  22 {
  23         int ret;
  24
  25         ret = register_trace_subsys_event(probe_subsys_event);
  26         WARN_ON(ret);
  27
  28         return 0;
  29 }
  30
  31 module_init(tp_sample_trace_init);
  32
  33 static void __exit tp_sample_trace_exit(void)
  34 {
  35         unregister_trace_subsys_event(probe_subsys_event);
  36         tracepoint_synchronize_unregister();
  37 }
  38
  39 module_exit(tp_sample_trace_exit);
  40
  41 MODULE_LICENSE("GPL");
  42 MODULE_AUTHOR("Mathieu Desnoyers");
  43 MODULE_DESCRIPTION("Tracepoint Probes Samples");