markers-test/test-mark-speed-local.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 #include <asm/system.h>
  12
  13 static void pmc_flush_cache(void)
  14   {
  15     /* write back and invalidate cache (a serializing instruction) */
  16
  17     __asm__ __volatile__ ( "wbinvd" : : : "memory" );
  18
  19     /* The wbinvd instruction does not wait for the external caches
  20      * to be flushed, but only requests that it be done.  The loop
  21      * is to be sure that enough time has elapsed, but the compiler
  22      * might simplify or even remove it.  The loop bound is for a
  23      * 512 KB L2 cache.  On a Pentium Pro/II/III, the loop uses
  24      * 2 cycles per iteration.
  25      *
  26      * Does wbinvd also cause the TLB to be flushed?
  27      * A comment in mtrr.c suggests that it does.
  28      */
  29     { register int i; for (i = 0; i < 512*1024; i++) { } }
  30   }
  31
  32
  33 static void noinline test2(const struct marker *mdata,
  34         void *call_private, ...)
  35 {
  36         unsigned char *ins = __builtin_return_address(0) - 5;
  37 #if 0
  38         /* not called */
  39         printk("ip %p\n", __builtin_return_address(0));
  40         printk("prev_ins %hX %hX %hX %hX %hX\n",
  41                 ins[0], ins[1], ins[2], ins[3], ins[4]);
  42 #endif //0
  43         ins[0] = 0x90;
  44         ins[1] = 0x8d;
  45         ins[2] = 0x74;
  46         ins[3] = 0x26;
  47         ins[4] = 0x00;
  48 }
  49
  50 /*
  51  * Generic marker flavor always available.
  52  * Note : the empty asm volatile with read constraint is used here instead of a
  53  * "used" attribute to fix a gcc 4.1.x bug.
  54  * Make sure the alignment of the structure in the __markers section will
  55  * not add unwanted padding between the beginning of the section and the
  56  * structure. Force alignment to the same alignment as the section start.
  57  */
  58 #define __my_trace_mark(generic, name, call_private, format, args...)   \
  59         do {                                                            \
  60                 static const char __mstrtab_##name[]                    \
  61                 __attribute__((section("__markers_strings")))           \
  62                 = #name "\0" format;                                    \
  63                 static struct marker __mark_##name                      \
  64                 __attribute__((section("__markers"), aligned(8))) =     \
  65                 { __mstrtab_##name, &__mstrtab_##name[sizeof(#name)],   \
  66                 0, 0, marker_probe_cb,                                  \
  67                 { __mark_empty_function, NULL}, NULL };                 \
  68                 __mark_check_format(format, ## args);                   \
  69                 if (!generic) {                                         \
  70                         if (unlikely(imv_read(__mark_##name.state)))    \
  71                                 test2                   \
  72                                         (&__mark_##name, call_private,  \
  73                                         ## args);               \
  74                 } else {                                                \
  75                         if (unlikely(_imv_read(__mark_##name.state)))   \
  76                                 test2                   \
  77                                         (&__mark_##name, call_private,  \
  78                                         ## args);               \
  79                 }                                                       \
  80         } while (0)
  81
  82 struct proc_dir_entry *pentry = NULL;
  83
  84 static inline void test(unsigned long arg, unsigned long arg2)
  85 {
  86         register int temp[5];
  87 #ifdef CACHEFLUSH
  88         pmc_flush_cache();
  89 #endif
  90         temp[2] = (temp[0] + 60) << 10;
  91         temp[3] = (temp[2] + 60) << 10;
  92         temp[4] = (temp[3] + 60) << 10;
  93         temp[0] = (temp[4] + 60) << 10;
  94         //asm volatile ("");
  95         //__my_trace_mark(1, kernel_debug_test, NULL, "%d %d %ld %ld", 2, current->pid, arg, arg2);
  96         barrier();
  97         test2(NULL, NULL, 2, 10, arg, arg2);
  98         barrier();      // make sure the compiler does not optimize marker conditions away!
  99         //__my_trace_mark(0, kernel_debug_test, NULL, "%d %d %ld %ld", 2, current->pid, arg, arg2);
 100 }
 101
 102 static int my_open(struct inode *inode, struct file *file)
 103 {
 104         unsigned int i;
 105         cycles_t cycles1, cycles2;
 106         unsigned long flags;
 107
 108         local_irq_save(flags);
 109 #ifdef CACHEFLUSH
 110         pmc_flush_cache();      /* initial write back, without cycle count */
 111         msleep(20);     /* wait for L2 flush */
 112 #endif
 113         rdtsc_barrier();
 114         cycles1 = get_cycles();
 115         rdtsc_barrier();
 116         for(i=0; i<2000; i++) {
 117                 test(i, i);
 118                 test(i, i);
 119                 test(i, i);
 120                 test(i, i);
 121                 test(i, i);
 122                 test(i, i);
 123                 test(i, i);
 124                 test(i, i);
 125                 test(i, i);
 126                 test(i, i);
 127         }
 128         rdtsc_barrier();
 129         cycles2 = get_cycles();
 130         rdtsc_barrier();
 131         local_irq_restore(flags);
 132         printk("cycles : %llu\n", cycles2-cycles1);
 133         return -EPERM;
 134 }
 135
 136
 137 static struct file_operations my_operations = {
 138         .open = my_open,
 139 };
 140
 141 int init_module(void)
 142 {
 143         pentry = create_proc_entry("testmark", 0444, NULL);
 144         if (pentry)
 145                 pentry->proc_fops = &my_operations;
 146
 147         return 0;
 148 }
 149
 150 void cleanup_module(void)
 151 {
 152         remove_proc_entry("testmark", NULL);
 153 }
 154
 155 MODULE_LICENSE("GPL");
 156 MODULE_AUTHOR("Mathieu Desnoyers");
 157 MODULE_DESCRIPTION("Marker Test");
 158 MODULE_VERSION("1.0");
 159