markers-test/test-mark-speed-empty.c

   1 /* test-mark.c
   2  *
   3  */
   4
   5 #include <linux/module.h>
   6 #include <linux/proc_fs.h>
   7 #include <linux/sched.h>
   8 #include <linux/timex.h>
   9 #include <linux/marker.h>
  10 #include <asm/ptrace.h>
  11 static void noinline test2(const struct marker *mdata,
  12         void *call_private, ...)
  13 {
  14         /* not called */
  15         printk("blah\n");
  16 }
  17
  18 /*
  19  * Generic marker flavor always available.
  20  * Note : the empty asm volatile with read constraint is used here instead of a
  21  * "used" attribute to fix a gcc 4.1.x bug.
  22  * Make sure the alignment of the structure in the __markers section will
  23  * not add unwanted padding between the beginning of the section and the
  24  * structure. Force alignment to the same alignment as the section start.
  25  */
  26 #define __my_trace_mark(generic, name, call_private, format, args...)   \
  27         do {                                                            \
  28                 static const char __mstrtab_##name[]                    \
  29                 __attribute__((section("__markers_strings")))           \
  30                 = #name "\0" format;                                    \
  31                 static struct marker __mark_##name                      \
  32                 __attribute__((section("__markers"), aligned(8))) =     \
  33                 { __mstrtab_##name, &__mstrtab_##name[sizeof(#name)],   \
  34                 0, 0, marker_probe_cb,                                  \
  35                 { __mark_empty_function, NULL}, NULL };                 \
  36                 __mark_check_format(format, ## args);                   \
  37                 if (!generic) {                                         \
  38                         if (unlikely(imv_read(__mark_##name.state)))    \
  39                                 test2                   \
  40                                         (&__mark_##name, call_private,  \
  41                                         ## args);               \
  42                 } else {                                                \
  43                         if (unlikely(_imv_read(__mark_##name.state)))   \
  44                                 test2                   \
  45                                         (&__mark_##name, call_private,  \
  46                                         ## args);               \
  47                 }                                                       \
  48         } while (0)
  49
  50         //asm volatile ("");
  51 struct proc_dir_entry *pentry = NULL;
  52
  53 static inline void test(unsigned long arg, unsigned long arg2)
  54 {
  55         asm volatile ("");
  56         //__my_trace_mark(1, kernel_debug_test, NULL, "%d %d %ld %ld", 2, current->pid, arg, arg2);
  57         //__my_trace_mark(0, kernel_debug_test, NULL, "%d %d %ld %ld", 2, current->pid, arg, arg2);
  58 }
  59
  60 static int my_open(struct inode *inode, struct file *file)
  61 {
  62         unsigned int i;
  63         cycles_t cycles1, cycles2;
  64         unsigned long flags;
  65
  66         local_irq_save(flags);
  67         rdtsc_barrier();
  68         cycles1 = get_cycles();
  69         rdtsc_barrier();
  70         for(i=0; i<20000; i++) {
  71                 test(i, i);
  72         }
  73         rdtsc_barrier();
  74         cycles2 = get_cycles();
  75         rdtsc_barrier();
  76         local_irq_restore(flags);
  77         printk("cycles : %llu\n", cycles2-cycles1);
  78         return -EPERM;
  79 }
  80
  81
  82 static struct file_operations my_operations = {
  83         .open = my_open,
  84 };
  85
  86 int init_module(void)
  87 {
  88         pentry = create_proc_entry("testmark", 0444, NULL);
  89         if (pentry)
  90                 pentry->proc_fops = &my_operations;
  91
  92         return 0;
  93 }
  94
  95 void cleanup_module(void)
  96 {
  97         remove_proc_entry("testmark", NULL);
  98 }
  99
 100 MODULE_LICENSE("GPL");
 101 MODULE_AUTHOR("Mathieu Desnoyers");
 102 MODULE_DESCRIPTION("Marker Test");
 103