1 /*
2  * Copyright 2016, Anton Blanchard, Michael Ellerman, IBM Corp.
3  * Licensed under GPLv2.
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 	return test_harness(test_mmap, "mmap_bench");
88 }
89