summaryrefslogtreecommitdiff
path: root/tools/testing/selftests/mm/thuge-gen.c
blob: ea7fd8fe287630928ab449d93a8ef2a0266eb819 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
// SPDX-License-Identifier: GPL-2.0
/* Test selecting other page sizes for mmap/shmget.

   Before running this huge pages for each huge page size must have been
   reserved.
   For large pages beyond MAX_PAGE_ORDER (like 1GB on x86) boot options must
   be used. 1GB wouldn't be tested if it isn't available.
   Also shmmax must be increased.
   And you need to run as root to work around some weird permissions in shm.
   And nothing using huge pages should run in parallel.
   When the program aborts you may need to clean up the shm segments with
   ipcrm -m by hand, like this
   sudo ipcs | awk '$1 == "0x00000000" {print $2}' | xargs -n1 sudo ipcrm -m
   (warning this will remove all if someone else uses them) */

#define _GNU_SOURCE 1
#include <sys/mman.h>
#include <stdlib.h>
#include <stdio.h>
#include <sys/ipc.h>
#include <sys/shm.h>
#include <sys/stat.h>
#include <glob.h>
#include <assert.h>
#include <unistd.h>
#include <stdarg.h>
#include <string.h>
#include "vm_util.h"
#include "../kselftest.h"

#define MAP_HUGE_2MB    (21 << MAP_HUGE_SHIFT)
#define MAP_HUGE_1GB    (30 << MAP_HUGE_SHIFT)
#define MAP_HUGE_SHIFT  26
#define MAP_HUGE_MASK   0x3f
#if !defined(MAP_HUGETLB)
#define MAP_HUGETLB	0x40000
#endif

#define SHM_HUGETLB     04000   /* segment will use huge TLB pages */
#define SHM_HUGE_SHIFT  26
#define SHM_HUGE_MASK   0x3f
#define SHM_HUGE_2MB    (21 << SHM_HUGE_SHIFT)
#define SHM_HUGE_1GB    (30 << SHM_HUGE_SHIFT)

#define NUM_PAGESIZES   5
#define NUM_PAGES 4

unsigned long page_sizes[NUM_PAGESIZES];
int num_page_sizes;

int ilog2(unsigned long v)
{
	int l = 0;
	while ((1UL << l) < v)
		l++;
	return l;
}

void show(unsigned long ps)
{
	char buf[100];

	if (ps == getpagesize())
		return;

	ksft_print_msg("%luMB: ", ps >> 20);

	fflush(stdout);
	snprintf(buf, sizeof buf,
		"cat /sys/kernel/mm/hugepages/hugepages-%lukB/free_hugepages",
		ps >> 10);
	system(buf);
}

unsigned long read_sysfs(int warn, char *fmt, ...)
{
	char *line = NULL;
	size_t linelen = 0;
	char buf[100];
	FILE *f;
	va_list ap;
	unsigned long val = 0;

	va_start(ap, fmt);
	vsnprintf(buf, sizeof buf, fmt, ap);
	va_end(ap);

	f = fopen(buf, "r");
	if (!f) {
		if (warn)
			ksft_print_msg("missing %s\n", buf);
		return 0;
	}
	if (getline(&line, &linelen, f) > 0) {
		sscanf(line, "%lu", &val);
	}
	fclose(f);
	free(line);
	return val;
}

unsigned long read_free(unsigned long ps)
{
	return read_sysfs(ps != getpagesize(),
			  "/sys/kernel/mm/hugepages/hugepages-%lukB/free_hugepages",
			  ps >> 10);
}

void test_mmap(unsigned long size, unsigned flags)
{
	char *map;
	unsigned long before, after;

	before = read_free(size);
	map = mmap(NULL, size*NUM_PAGES, PROT_READ|PROT_WRITE,
			MAP_PRIVATE|MAP_ANONYMOUS|MAP_HUGETLB|flags, -1, 0);
	if (map == MAP_FAILED)
		ksft_exit_fail_msg("mmap: %s\n", strerror(errno));

	memset(map, 0xff, size*NUM_PAGES);
	after = read_free(size);

	show(size);
	ksft_test_result(size == getpagesize() || (before - after) == NUM_PAGES,
			 "%s mmap\n", __func__);

	if (munmap(map, size * NUM_PAGES))
		ksft_exit_fail_msg("%s: unmap %s\n", __func__, strerror(errno));
}

void test_shmget(unsigned long size, unsigned flags)
{
	int id;
	unsigned long before, after;
	struct shm_info i;
	char *map;

	before = read_free(size);
	id = shmget(IPC_PRIVATE, size * NUM_PAGES, IPC_CREAT|0600|flags);
	if (id < 0) {
		if (errno == EPERM) {
			ksft_test_result_skip("shmget requires root privileges: %s\n",
					      strerror(errno));
			return;
		}
		ksft_exit_fail_msg("shmget: %s\n", strerror(errno));
	}

	if (shmctl(id, SHM_INFO, (void *)&i) < 0)
		ksft_exit_fail_msg("shmctl: %s\n", strerror(errno));

	map = shmat(id, NULL, 0600);
	if (map == MAP_FAILED)
		ksft_exit_fail_msg("shmat: %s\n", strerror(errno));

	shmctl(id, IPC_RMID, NULL);

	memset(map, 0xff, size*NUM_PAGES);
	after = read_free(size);

	show(size);
	ksft_test_result(size == getpagesize() || (before - after) == NUM_PAGES,
			 "%s: mmap\n", __func__);
	if (shmdt(map))
		ksft_exit_fail_msg("%s: shmdt: %s\n", __func__, strerror(errno));
}

void find_pagesizes(void)
{
	unsigned long largest = getpagesize();
	int i;
	glob_t g;

	glob("/sys/kernel/mm/hugepages/hugepages-*kB", 0, NULL, &g);
	assert(g.gl_pathc <= NUM_PAGESIZES);
	for (i = 0; (i < g.gl_pathc) && (num_page_sizes < NUM_PAGESIZES); i++) {
		sscanf(g.gl_pathv[i], "/sys/kernel/mm/hugepages/hugepages-%lukB",
				&page_sizes[num_page_sizes]);
		page_sizes[num_page_sizes] <<= 10;
		ksft_print_msg("Found %luMB\n", page_sizes[i] >> 20);

		if (page_sizes[num_page_sizes] > largest)
			largest = page_sizes[i];

		if (read_free(page_sizes[num_page_sizes]) >= NUM_PAGES)
			num_page_sizes++;
		else
			ksft_print_msg("SKIP for size %lu MB as not enough huge pages, need %u\n",
				       page_sizes[num_page_sizes] >> 20, NUM_PAGES);
	}
	globfree(&g);

	if (read_sysfs(0, "/proc/sys/kernel/shmmax") < NUM_PAGES * largest)
		ksft_exit_fail_msg("Please do echo %lu > /proc/sys/kernel/shmmax",
				   largest * NUM_PAGES);

#if defined(__x86_64__)
	if (largest != 1U<<30) {
		ksft_exit_fail_msg("No GB pages available on x86-64\n"
				   "Please boot with hugepagesz=1G hugepages=%d\n", NUM_PAGES);
	}
#endif
}

int main(void)
{
	unsigned default_hps = default_huge_page_size();
	int i;

	ksft_print_header();

	find_pagesizes();

	if (!num_page_sizes)
		ksft_finished();

	ksft_set_plan(2 * num_page_sizes + 3);

	for (i = 0; i < num_page_sizes; i++) {
		unsigned long ps = page_sizes[i];
		int arg = ilog2(ps) << MAP_HUGE_SHIFT;

		ksft_print_msg("Testing %luMB mmap with shift %x\n", ps >> 20, arg);
		test_mmap(ps, MAP_HUGETLB | arg);
	}

	ksft_print_msg("Testing default huge mmap\n");
	test_mmap(default_hps, MAP_HUGETLB);

	ksft_print_msg("Testing non-huge shmget\n");
	test_shmget(getpagesize(), 0);

	for (i = 0; i < num_page_sizes; i++) {
		unsigned long ps = page_sizes[i];
		int arg = ilog2(ps) << SHM_HUGE_SHIFT;
		ksft_print_msg("Testing %luMB shmget with shift %x\n", ps >> 20, arg);
		test_shmget(ps, SHM_HUGETLB | arg);
	}

	ksft_print_msg("default huge shmget\n");
	test_shmget(default_hps, SHM_HUGETLB);

	ksft_finished();
}