tests/kernel/test-compact.c

   1 /* test-time-probe.c
   2  *
   3  * Test time spent in a LTTng instrumentation probe.
   4  */
   5
   6
   7 #include <ltt/ltt-facility-select-compact.h>
   8 #include <ltt/ltt-facility-compact.h>
   9
  10 #include <linux/init.h>
  11 #include <linux/module.h>
  12 #include <linux/ltt-core.h>
  13 #include <linux/timex.h>
  14
  15
  16 /* Event logged : 4 bytes. Let's use 1MB of
  17  * buffers. 1MB / 4bytes = 262144 (plus heartbeats). So, if we write 20000
  18  * event, we should not lose events. Check event lost count after tests. */
  19
  20 #define NR_LOOPS 20000
  21
  22 static int ltt_test_init(void)
  23 {
  24         unsigned int i;
  25         cycles_t time1, time2, time;
  26         cycles_t tot_time = 0;
  27         unsigned long flags;
  28         printk(KERN_ALERT "test init\n");
  29
  30         local_irq_save(flags);
  31         time1 = get_cycles();
  32         for(i=0; i<NR_LOOPS; i++) {
  33                 trace_compact_event_a();
  34                 trace_compact_event_c(get_cycles());
  35                 trace_compact_event_d(0xFF);
  36                 trace_compact_event_e(0xFF, 0xFAFAFA);
  37         }
  38         time2 = get_cycles();
  39         time = time2 - time1;
  40         tot_time += time;
  41         local_irq_restore(flags);
  42
  43         printk(KERN_ALERT "test results : time per probe\n");
  44         printk(KERN_ALERT "number of loops : %d\n", NR_LOOPS);
  45         printk(KERN_ALERT "total time : %llu\n", tot_time);
  46
  47         printk(KERN_ALERT "test end\n");
  48
  49         return -EAGAIN; /* Fail will directly unload the module */
  50 }
  51
  52 static void ltt_test_exit(void)
  53 {
  54         printk(KERN_ALERT "test exit\n");
  55 }
  56
  57 module_init(ltt_test_init)
  58 module_exit(ltt_test_exit)
  59
  60 MODULE_LICENSE("GPL");
  61 MODULE_AUTHOR("Mathieu Desnoyers");
  62 MODULE_DESCRIPTION("Linux Trace Toolkit Test");
  63