LXR linux/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 */
  15static 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
  21static 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
  31module_init(tp_sample_trace_init);
  32
  33static void __exit tp_sample_trace_exit(void)
  34{
  35        unregister_trace_subsys_event(probe_subsys_event);
  36        tracepoint_synchronize_unregister();
  37}
  38
  39module_exit(tp_sample_trace_exit);
  40
  41MODULE_LICENSE("GPL");
  42MODULE_AUTHOR("Mathieu Desnoyers");
  43MODULE_DESCRIPTION("Tracepoint Probes Samples");
  44