tests/kernel/marker-example.c

   1 /* marker-example.c
   2  *
   3  * Executes a marker when /proc/marker-example is opened.
   4  *
   5  * (C) Copyright 2007 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
   6  *
   7  * This file is released under the GPLv2.
   8  * See the file COPYING for more details.
   9  */
  10
  11 #include <linux/module.h>
  12 #include <linux/marker.h>
  13 #include <linux/sched.h>
  14 #include <linux/proc_fs.h>
  15
  16 struct proc_dir_entry *pentry_example = NULL;
  17
  18 static int my_open(struct inode *inode, struct file *file)
  19 {
  20         int i;
  21
  22         MARK(subsystem_event, "%d %s %*.*r", 123, "example string",
  23                 sizeof(current), __alignof__(current), current);
  24         for (i=0; i<10; i++) {
  25                 MARK(subsystem_eventb, MARK_NOARGS);
  26         }
  27         return -EPERM;
  28 }
  29
  30 static struct file_operations mark_ops = {
  31         .open = my_open,
  32 };
  33
  34 static int example_init(void)
  35 {
  36         printk(KERN_ALERT "example init\n");
  37         pentry_example = create_proc_entry("marker-example", 0444, NULL);
  38         if (pentry_example)
  39                 pentry_example->proc_fops = &mark_ops;
  40         else
  41                 return -EPERM;
  42         return 0;
  43 }
  44
  45 static void example_exit(void)
  46 {
  47         printk(KERN_ALERT "example exit\n");
  48         remove_proc_entry("marker-example", NULL);
  49 }
  50
  51 module_init(example_init)
  52 module_exit(example_exit)
  53
  54 MODULE_LICENSE("GPL");
  55 MODULE_AUTHOR("Mathieu Desnoyers");
  56 MODULE_DESCRIPTION("Linux Trace Toolkit example");