summaryrefslogtreecommitdiff
path: root/tools/testing/selftests/vm/gup_test.c
blob: 1e662d59c502a806cb0bf8f7983a19f7663f9625 (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
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>
#include "../../../../mm/gup_test.h"

#define MB (1UL << 20)
#define PAGE_SIZE sysconf(_SC_PAGESIZE)

/* Just the flags we need, copied from mm.h: */
#define FOLL_WRITE	0x01	/* check pte is writable */
#define FOLL_TOUCH	0x02	/* mark page accessed */

static char *cmd_to_str(unsigned long cmd)
{
	switch (cmd) {
	case GUP_FAST_BENCHMARK:
		return "GUP_FAST_BENCHMARK";
	case PIN_FAST_BENCHMARK:
		return "PIN_FAST_BENCHMARK";
	case PIN_LONGTERM_BENCHMARK:
		return "PIN_LONGTERM_BENCHMARK";
	case GUP_BASIC_TEST:
		return "GUP_BASIC_TEST";
	case PIN_BASIC_TEST:
		return "PIN_BASIC_TEST";
	case DUMP_USER_PAGES_TEST:
		return "DUMP_USER_PAGES_TEST";
	}
	return "Unknown command";
}

int main(int argc, char **argv)
{
	struct gup_test gup = { 0 };
	unsigned long size = 128 * MB;
	int i, fd, filed, opt, nr_pages = 1, thp = -1, repeats = 1, write = 1;
	unsigned long cmd = GUP_FAST_BENCHMARK;
	int flags = MAP_PRIVATE, touch = 0;
	char *file = "/dev/zero";
	char *p;

	while ((opt = getopt(argc, argv, "m:r:n:F:f:abctTLUuwWSHpz")) != -1) {
		switch (opt) {
		case 'a':
			cmd = PIN_FAST_BENCHMARK;
			break;
		case 'b':
			cmd = PIN_BASIC_TEST;
			break;
		case 'L':
			cmd = PIN_LONGTERM_BENCHMARK;
			break;
		case 'c':
			cmd = DUMP_USER_PAGES_TEST;
			/*
			 * Dump page 0 (index 1). May be overridden later, by
			 * user's non-option arguments.
			 *
			 * .which_pages is zero-based, so that zero can mean "do
			 * nothing".
			 */
			gup.which_pages[0] = 1;
			break;
		case 'p':
			/* works only with DUMP_USER_PAGES_TEST */
			gup.test_flags |= GUP_TEST_FLAG_DUMP_PAGES_USE_PIN;
			break;
		case 'F':
			/* strtol, so you can pass flags in hex form */
			gup.gup_flags = strtol(optarg, 0, 0);
			break;
		case 'm':
			size = atoi(optarg) * MB;
			break;
		case 'r':
			repeats = atoi(optarg);
			break;
		case 'n':
			nr_pages = atoi(optarg);
			break;
		case 't':
			thp = 1;
			break;
		case 'T':
			thp = 0;
			break;
		case 'U':
			cmd = GUP_BASIC_TEST;
			break;
		case 'u':
			cmd = GUP_FAST_BENCHMARK;
			break;
		case 'w':
			write = 1;
			break;
		case 'W':
			write = 0;
			break;
		case 'f':
			file = optarg;
			break;
		case 'S':
			flags &= ~MAP_PRIVATE;
			flags |= MAP_SHARED;
			break;
		case 'H':
			flags |= (MAP_HUGETLB | MAP_ANONYMOUS);
			break;
		case 'z':
			/* fault pages in gup, do not fault in userland */
			touch = 1;
			break;
		default:
			return -1;
		}
	}

	if (optind < argc) {
		int extra_arg_count = 0;
		/*
		 * For example:
		 *
		 *   ./gup_test -c 0 1 0x1001
		 *
		 * ...to dump pages 0, 1, and 4097
		 */

		while ((optind < argc) &&
		       (extra_arg_count < GUP_TEST_MAX_PAGES_TO_DUMP)) {
			/*
			 * Do the 1-based indexing here, so that the user can
			 * use normal 0-based indexing on the command line.
			 */
			long page_index = strtol(argv[optind], 0, 0) + 1;

			gup.which_pages[extra_arg_count] = page_index;
			extra_arg_count++;
			optind++;
		}
	}

	filed = open(file, O_RDWR|O_CREAT);
	if (filed < 0) {
		perror("open");
		exit(filed);
	}

	gup.nr_pages_per_call = nr_pages;
	if (write)
		gup.gup_flags |= FOLL_WRITE;

	fd = open("/sys/kernel/debug/gup_test", O_RDWR);
	if (fd == -1) {
		perror("open");
		exit(1);
	}

	p = mmap(NULL, size, PROT_READ | PROT_WRITE, flags, filed, 0);
	if (p == MAP_FAILED) {
		perror("mmap");
		exit(1);
	}
	gup.addr = (unsigned long)p;

	if (thp == 1)
		madvise(p, size, MADV_HUGEPAGE);
	else if (thp == 0)
		madvise(p, size, MADV_NOHUGEPAGE);

	/*
	 * FOLL_TOUCH, in gup_test, is used as an either/or case: either
	 * fault pages in from the kernel via FOLL_TOUCH, or fault them
	 * in here, from user space. This allows comparison of performance
	 * between those two cases.
	 */
	if (touch) {
		gup.gup_flags |= FOLL_TOUCH;
	} else {
		for (; (unsigned long)p < gup.addr + size; p += PAGE_SIZE)
			p[0] = 0;
	}

	/* Only report timing information on the *_BENCHMARK commands: */
	if ((cmd == PIN_FAST_BENCHMARK) || (cmd == GUP_FAST_BENCHMARK) ||
	     (cmd == PIN_LONGTERM_BENCHMARK)) {
		for (i = 0; i < repeats; i++) {
			gup.size = size;
			if (ioctl(fd, cmd, &gup))
				perror("ioctl"), exit(1);

			printf("%s: Time: get:%lld put:%lld us",
			       cmd_to_str(cmd), gup.get_delta_usec,
			       gup.put_delta_usec);
			if (gup.size != size)
				printf(", truncated (size: %lld)", gup.size);
			printf("\n");
		}
	} else {
		gup.size = size;
		if (ioctl(fd, cmd, &gup)) {
			perror("ioctl");
			exit(1);
		}

		printf("%s: done\n", cmd_to_str(cmd));
		if (gup.size != size)
			printf("Truncated (size: %lld)\n", gup.size);
	}

	return 0;
}