1/*
2 * Stress test for transparent huge pages, memory compaction and migration.
3 *
4 * Authors: Konstantin Khlebnikov <koct9i@gmail.com>
5 *
6 * This is free and unencumbered software released into the public domain.
7 */
8
9#include <stdlib.h>
10#include <stdio.h>
11#include <stdint.h>
12#include <err.h>
13#include <time.h>
14#include <unistd.h>
15#include <fcntl.h>
16#include <string.h>
17#include <sys/mman.h>
18#include "vm_util.h"
19
20int backing_fd = -1;
21int mmap_flags = MAP_ANONYMOUS | MAP_NORESERVE | MAP_PRIVATE;
22#define PROT_RW (PROT_READ | PROT_WRITE)
23
24int main(int argc, char **argv)
25{
26	size_t ram, len;
27	void *ptr, *p;
28	struct timespec start, a, b;
29	int i = 0;
30	char *name = NULL;
31	double s;
32	uint8_t *map;
33	size_t map_len;
34	int pagemap_fd;
35	int duration = 0;
36
37	ram = sysconf(_SC_PHYS_PAGES);
38	if (ram > SIZE_MAX / psize() / 4)
39		ram = SIZE_MAX / 4;
40	else
41		ram *= psize();
42	len = ram;
43
44	while (++i < argc) {
45		if (!strcmp(argv[i], "-h"))
46			errx(1, "usage: %s [-f <filename>] [-d <duration>] [size in MiB]", argv[0]);
47		else if (!strcmp(argv[i], "-f"))
48			name = argv[++i];
49		else if (!strcmp(argv[i], "-d"))
50			duration = atoi(argv[++i]);
51		else
52			len = atoll(argv[i]) << 20;
53	}
54
55	if (name) {
56		backing_fd = open(name, O_RDWR);
57		if (backing_fd == -1)
58			errx(2, "open %s", name);
59		mmap_flags = MAP_SHARED;
60	}
61
62	warnx("allocate %zd transhuge pages, using %zd MiB virtual memory"
63	      " and %zd MiB of ram", len >> HPAGE_SHIFT, len >> 20,
64	      ram >> (20 + HPAGE_SHIFT - pshift() - 1));
65
66	pagemap_fd = open("/proc/self/pagemap", O_RDONLY);
67	if (pagemap_fd < 0)
68		err(2, "open pagemap");
69
70	len -= len % HPAGE_SIZE;
71	ptr = mmap(NULL, len + HPAGE_SIZE, PROT_RW, mmap_flags, backing_fd, 0);
72	if (ptr == MAP_FAILED)
73		err(2, "initial mmap");
74	ptr += HPAGE_SIZE - (uintptr_t)ptr % HPAGE_SIZE;
75
76	if (madvise(ptr, len, MADV_HUGEPAGE))
77		err(2, "MADV_HUGEPAGE");
78
79	map_len = ram >> (HPAGE_SHIFT - 1);
80	map = malloc(map_len);
81	if (!map)
82		errx(2, "map malloc");
83
84	clock_gettime(CLOCK_MONOTONIC, &start);
85
86	while (1) {
87		int nr_succeed = 0, nr_failed = 0, nr_pages = 0;
88
89		memset(map, 0, map_len);
90
91		clock_gettime(CLOCK_MONOTONIC, &a);
92		for (p = ptr; p < ptr + len; p += HPAGE_SIZE) {
93			int64_t pfn;
94
95			pfn = allocate_transhuge(p, pagemap_fd);
96
97			if (pfn < 0) {
98				nr_failed++;
99			} else {
100				size_t idx = pfn >> (HPAGE_SHIFT - pshift());
101
102				nr_succeed++;
103				if (idx >= map_len) {
104					map = realloc(map, idx + 1);
105					if (!map)
106						errx(2, "map realloc");
107					memset(map + map_len, 0, idx + 1 - map_len);
108					map_len = idx + 1;
109				}
110				if (!map[idx])
111					nr_pages++;
112				map[idx] = 1;
113			}
114
115			/* split transhuge page, keep last page */
116			if (madvise(p, HPAGE_SIZE - psize(), MADV_DONTNEED))
117				err(2, "MADV_DONTNEED");
118		}
119		clock_gettime(CLOCK_MONOTONIC, &b);
120		s = b.tv_sec - a.tv_sec + (b.tv_nsec - a.tv_nsec) / 1000000000.;
121
122		warnx("%.3f s/loop, %.3f ms/page, %10.3f MiB/s\t"
123		      "%4d succeed, %4d failed, %4d different pages",
124		      s, s * 1000 / (len >> HPAGE_SHIFT), len / s / (1 << 20),
125		      nr_succeed, nr_failed, nr_pages);
126
127		if (duration > 0 && b.tv_sec - start.tv_sec >= duration)
128			return 0;
129	}
130}
131