samples/trace_events/trace-events-sample.c

   1 #include <linux/module.h>
   2 #include <linux/kthread.h>
   3
   4 /*
   5  * Any file that uses trace points, must include the header.
   6  * But only one file, must include the header by defining
   7  * CREATE_TRACE_POINTS first.  This will make the C code that
   8  * creates the handles for the trace points.
   9  */
  10 #define CREATE_TRACE_POINTS
  11 #include "trace-events-sample.h"
  12
  13
  14 static void simple_thread_func(int cnt)
  15 {
  16         set_current_state(TASK_INTERRUPTIBLE);
  17         schedule_timeout(HZ);
  18         trace_foo_bar("hello", cnt);
  19 }
  20
  21 static int simple_thread(void *arg)
  22 {
  23         int cnt = 0;
  24
  25         while (!kthread_should_stop())
  26                 simple_thread_func(cnt++);
  27
  28         return 0;
  29 }
  30
  31 static struct task_struct *simple_tsk;
  32
  33 static int __init trace_event_init(void)
  34 {
  35         simple_tsk = kthread_run(simple_thread, NULL, "event-sample");
  36         if (IS_ERR(simple_tsk))
  37                 return -1;
  38
  39         return 0;
  40 }
  41
  42 static void __exit trace_event_exit(void)
  43 {
  44         kthread_stop(simple_tsk);
  45 }
  46
  47 module_init(trace_event_init);
  48 module_exit(trace_event_exit);
  49
  50 MODULE_AUTHOR("Steven Rostedt");
  51 MODULE_DESCRIPTION("trace-events-sample");
  52 MODULE_LICENSE("GPL");