trunk/tests/kernel/test-lttng-tp.c

   1 /* test-lttng-tp.c
   2  *
   3  * Test lttng event write.
   4  */
   5
   6 #include <linux/jiffies.h>
   7 #include <linux/compiler.h>
   8 #include <linux/init.h>
   9 #include <linux/module.h>
  10 #include <linux/math64.h>
  11 #include <linux/proc_fs.h>
  12 #include "tp-test.h"
  13 #include <asm/timex.h>
  14 #include <asm/system.h>
  15
  16 #define NR_LOOPS 200000
  17
  18 DEFINE_TRACE(kernel_test);
  19
  20 struct proc_dir_entry *pentry = NULL;
  21
  22 int test_val;
  23
  24 static void do_testbaseline(void)
  25 {
  26         unsigned long flags;
  27         unsigned int i;
  28         cycles_t time1, time2, time;
  29         u32 rem;
  30
  31         local_irq_save(flags);
  32         preempt_disable();
  33         time1 = get_cycles();
  34         for (i = 0; i < NR_LOOPS; i++) {
  35                 asm volatile ("");
  36         }
  37         time2 = get_cycles();
  38         local_irq_restore(flags);
  39         preempt_enable();
  40         time = time2 - time1;
  41
  42         printk(KERN_ALERT "test results: time for baseline\n");
  43         printk(KERN_ALERT "number of loops: %d\n", NR_LOOPS);
  44         printk(KERN_ALERT "total time: %llu\n", time);
  45         time = div_u64_rem(time, NR_LOOPS, &rem);
  46         printk(KERN_ALERT "-> baseline takes %llu cycles\n", time);
  47         printk(KERN_ALERT "test end\n");
  48 }
  49
  50 static void do_test_tp(void)
  51 {
  52         unsigned long flags;
  53         unsigned int i;
  54         cycles_t time1, time2, time;
  55         u32 rem;
  56
  57         local_irq_save(flags);
  58         preempt_disable();
  59         time1 = get_cycles();
  60         for (i = 0; i < NR_LOOPS; i++) {
  61                 trace_kernel_test((void *)999, (void *)10);
  62         }
  63         time2 = get_cycles();
  64         local_irq_restore(flags);
  65         preempt_enable();
  66         time = time2 - time1;
  67
  68         printk(KERN_ALERT "test results: time for one probe\n");
  69         printk(KERN_ALERT "number of loops: %d\n", NR_LOOPS);
  70         printk(KERN_ALERT "total time: %llu\n", time);
  71         time = div_u64_rem(time, NR_LOOPS, &rem);
  72         printk(KERN_ALERT "-> one probe takes %llu cycles\n", time);
  73         printk(KERN_ALERT "test end\n");
  74 }
  75
  76 static int my_open(struct inode *inode, struct file *file)
  77 {
  78         do_testbaseline();
  79         do_test_tp();
  80
  81         return -EPERM;
  82 }
  83
  84 static const struct file_operations my_operations = {
  85         .open = my_open,
  86 };
  87
  88 static int ltt_test_init(void)
  89 {
  90         printk(KERN_ALERT "test init\n");
  91         pentry = create_proc_entry("testltt", 0444, NULL);
  92         if (pentry)
  93                 pentry->proc_fops = &my_operations;
  94         return 0;
  95 }
  96
  97 static void ltt_test_exit(void)
  98 {
  99         printk(KERN_ALERT "test exit\n");
 100         remove_proc_entry("testltt", NULL);
 101 }
 102
 103 module_init(ltt_test_init)
 104 module_exit(ltt_test_exit)
 105
 106 MODULE_LICENSE("GPL");
 107 MODULE_AUTHOR("Mathieu Desnoyers");
 108 MODULE_DESCRIPTION("TP test");