tools/testing/selftests/powerpc/benchmarks/futex_bench.c

   1 /*
   2  * Copyright 2016, Anton Blanchard, Michael Ellerman, IBM Corp.
   3  * Licensed under GPLv2.
   4  */
   5
   6 #define _GNU_SOURCE
   7
   8 #include <stdio.h>
   9 #include <sys/syscall.h>
  10 #include <time.h>
  11 #include <unistd.h>
  12 #include <linux/futex.h>
  13
  14 #include "utils.h"
  15
  16 #define ITERATIONS 100000000
  17
  18 #define futex(A, B, C, D, E, F)  syscall(__NR_futex, A, B, C, D, E, F)
  19
  20 int test_futex(void)
  21 {
  22         struct timespec ts_start, ts_end;
  23         unsigned long i = ITERATIONS;
  24
  25         clock_gettime(CLOCK_MONOTONIC, &ts_start);
  26
  27         while (i--) {
  28                 unsigned int addr = 0;
  29                 futex(&addr, FUTEX_WAKE, 1, NULL, NULL, 0);
  30         }
  31
  32         clock_gettime(CLOCK_MONOTONIC, &ts_end);
  33
  34         printf("time = %.6f\n", ts_end.tv_sec - ts_start.tv_sec + (ts_end.tv_nsec - ts_start.tv_nsec) / 1e9);
  35
  36         return 0;
  37 }
  38
  39 int main(void)
  40 {
  41         return test_harness(test_futex, "futex_bench");
  42 }