tests/benchmark/test_looplen.c

   1 // SPDX-FileCopyrightText: 2009 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   2 //
   3 // SPDX-License-Identifier: GPL-2.0-or-later
   4
   5 /*
   6  * Userspace RCU library - test program
   7  */
   8
   9 #include <stdio.h>
  10 #include <pthread.h>
  11 #include <stdlib.h>
  12 #include <string.h>
  13 #include <sys/types.h>
  14 #include <sys/wait.h>
  15 #include <unistd.h>
  16 #include <stdio.h>
  17 #include <sched.h>
  18 #include <errno.h>
  19
  20 #include <urcu/arch.h>
  21 #include <urcu/assert.h>
  22
  23 #ifndef DYNAMIC_LINK_TEST
  24 #define _LGPL_SOURCE
  25 #else
  26 #define debug_yield_read()
  27 #endif
  28 #include <urcu.h>
  29
  30 static inline void loop_sleep(unsigned long loops)
  31 {
  32         while (loops-- != 0)
  33                 caa_cpu_relax();
  34 }
  35
  36 #define LOOPS 1048576
  37 #define TESTS 10
  38
  39 int main(void)
  40 {
  41         unsigned long i;
  42         caa_cycles_t time1, time2;
  43         caa_cycles_t time_tot = 0;
  44         double cpl;
  45
  46         for (i = 0; i < TESTS; i++) {
  47                 time1 = caa_get_cycles();
  48                 loop_sleep(LOOPS);
  49                 time2 = caa_get_cycles();
  50                 time_tot += time2 - time1;
  51         }
  52         cpl = ((double)time_tot) / (double)TESTS / (double)LOOPS;
  53
  54         printf("CALIBRATION : %g cycles per loop\n", cpl);
  55         printf("time_tot = %llu, LOOPS = %d, TESTS = %d\n",
  56                (unsigned long long) time_tot, LOOPS, TESTS);
  57
  58         return 0;
  59 }