// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright 2016, Anton Blanchard, Michael Ellerman, IBM Corp.
 */

#include <stdio.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <time.h>
#include <getopt.h>

#include "utils.h"

#define ITERATIONS 5000000

#define MEMSIZE (1UL << 27)
#define PAGE_SIZE (1UL << 16)
#define CHUNK_COUNT (MEMSIZE/PAGE_SIZE)

static int pg_fault;
static int iterations = ITERATIONS;

static struct option options[] = {
        { "pgfault", no_argument, &pg_fault, 1 },
        { "iterations", required_argument, 0, 'i' },
        { 0, },
};

static void usage(void)
{
        printf("mmap_bench <--pgfault> <--iterations count>\n");
}

int test_mmap(void)
{
        struct timespec ts_start, ts_end;
        unsigned long i = iterations;

        clock_gettime(CLOCK_MONOTONIC, &ts_start);

        while (i--) {
                char *c = mmap(NULL, MEMSIZE, PROT_READ|PROT_WRITE,
                               MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
                FAIL_IF(c == MAP_FAILED);
                if (pg_fault) {
                        int count;
                        for (count = 0; count < CHUNK_COUNT; count++)
                                c[count << 16] = 'c';
                }
                munmap(c, MEMSIZE);
        }

        clock_gettime(CLOCK_MONOTONIC, &ts_end);

        printf("time = %.6f\n", ts_end.tv_sec - ts_start.tv_sec + (ts_end.tv_nsec - ts_start.tv_nsec) / 1e9);

        return 0;
}

int main(int argc, char *argv[])
{
        signed char c;
        while (1) {
                int option_index = 0;

                c = getopt_long(argc, argv, "", options, &option_index);

                if (c == -1)
                        break;

                switch (c) {
                case 0:
                        if (options[option_index].flag != 0)
                                break;

                        usage();
                        exit(1);
                        break;
                case 'i':
                        iterations = atoi(optarg);
                        break;
                default:
                        usage();
                        exit(1);
                }
        }

        test_harness_set_timeout(300);
        return test_harness(test_mmap, "mmap_bench");
}