root/tools/testing/selftests/powerpc/benchmarks/mmap_bench.c

DEFINITIONS

1. usage
2. test_mmap
3. main

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright 2016, Anton Blanchard, Michael Ellerman, IBM Corp.
   4  */
   5 
   6 #include <stdio.h>
   7 #include <stdlib.h>
   8 #include <sys/mman.h>
   9 #include <time.h>
  10 #include <getopt.h>
  11 
  12 #include "utils.h"
  13 
  14 #define ITERATIONS 5000000
  15 
  16 #define MEMSIZE (1UL << 27)
  17 #define PAGE_SIZE (1UL << 16)
  18 #define CHUNK_COUNT (MEMSIZE/PAGE_SIZE)
  19 
  20 static int pg_fault;
  21 static int iterations = ITERATIONS;
  22 
  23 static struct option options[] = {
  24         { "pgfault", no_argument, &pg_fault, 1 },
  25         { "iterations", required_argument, 0, 'i' },
  26         { 0, },
  27 };
  28 
  29 static void usage(void)
  30 {
  31         printf("mmap_bench <--pgfault> <--iterations count>\n");
  32 }
  33 
  34 int test_mmap(void)
  35 {
  36         struct timespec ts_start, ts_end;
  37         unsigned long i = iterations;
  38 
  39         clock_gettime(CLOCK_MONOTONIC, &ts_start);
  40 
  41         while (i--) {
  42                 char *c = mmap(NULL, MEMSIZE, PROT_READ|PROT_WRITE,
  43                                MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
  44                 FAIL_IF(c == MAP_FAILED);
  45                 if (pg_fault) {
  46                         int count;
  47                         for (count = 0; count < CHUNK_COUNT; count++)
  48                                 c[count << 16] = 'c';
  49                 }
  50                 munmap(c, MEMSIZE);
  51         }
  52 
  53         clock_gettime(CLOCK_MONOTONIC, &ts_end);
  54 
  55         printf("time = %.6f\n", ts_end.tv_sec - ts_start.tv_sec + (ts_end.tv_nsec - ts_start.tv_nsec) / 1e9);
  56 
  57         return 0;
  58 }
  59 
  60 int main(int argc, char *argv[])
  61 {
  62         signed char c;
  63         while (1) {
  64                 int option_index = 0;
  65 
  66                 c = getopt_long(argc, argv, "", options, &option_index);
  67 
  68                 if (c == -1)
  69                         break;
  70 
  71                 switch (c) {
  72                 case 0:
  73                         if (options[option_index].flag != 0)
  74                                 break;
  75 
  76                         usage();
  77                         exit(1);
  78                         break;
  79                 case 'i':
  80                         iterations = atoi(optarg);
  81                         break;
  82                 default:
  83                         usage();
  84                         exit(1);
  85                 }
  86         }
  87 
  88         test_harness_set_timeout(300);
  89         return test_harness(test_mmap, "mmap_bench");
  90 }