xref: /linux/tools/testing/selftests/mm/gup_test.c (revision 509d3f45847627f4c5cdce004c3ec79262b5239c)
1 #define __SANE_USERSPACE_TYPES__ // Use ll64
2 #include <fcntl.h>
3 #include <errno.h>
4 #include <stdio.h>
5 #include <stdlib.h>
6 #include <unistd.h>
7 #include <dirent.h>
8 #include <sys/ioctl.h>
9 #include <sys/mman.h>
10 #include <sys/stat.h>
11 #include <sys/types.h>
12 #include <pthread.h>
13 #include <assert.h>
14 #include <mm/gup_test.h>
15 #include "kselftest.h"
16 #include "vm_util.h"
17 
18 #define MB (1UL << 20)
19 
20 /* Just the flags we need, copied from the kernel internals. */
21 #define FOLL_WRITE	0x01	/* check pte is writable */
22 
23 #define GUP_TEST_FILE "/sys/kernel/debug/gup_test"
24 
25 static unsigned long cmd = GUP_FAST_BENCHMARK;
26 static int gup_fd, repeats = 1;
27 static unsigned long size = 128 * MB;
28 /* Serialize prints */
29 static pthread_mutex_t print_mutex = PTHREAD_MUTEX_INITIALIZER;
30 
cmd_to_str(unsigned long cmd)31 static char *cmd_to_str(unsigned long cmd)
32 {
33 	switch (cmd) {
34 	case GUP_FAST_BENCHMARK:
35 		return "GUP_FAST_BENCHMARK";
36 	case PIN_FAST_BENCHMARK:
37 		return "PIN_FAST_BENCHMARK";
38 	case PIN_LONGTERM_BENCHMARK:
39 		return "PIN_LONGTERM_BENCHMARK";
40 	case GUP_BASIC_TEST:
41 		return "GUP_BASIC_TEST";
42 	case PIN_BASIC_TEST:
43 		return "PIN_BASIC_TEST";
44 	case DUMP_USER_PAGES_TEST:
45 		return "DUMP_USER_PAGES_TEST";
46 	}
47 	return "Unknown command";
48 }
49 
gup_thread(void * data)50 void *gup_thread(void *data)
51 {
52 	struct gup_test gup = *(struct gup_test *)data;
53 	int i, status;
54 
55 	/* Only report timing information on the *_BENCHMARK commands: */
56 	if ((cmd == PIN_FAST_BENCHMARK) || (cmd == GUP_FAST_BENCHMARK) ||
57 	     (cmd == PIN_LONGTERM_BENCHMARK)) {
58 		for (i = 0; i < repeats; i++) {
59 			gup.size = size;
60 			status = ioctl(gup_fd, cmd, &gup);
61 			if (status)
62 				break;
63 
64 			pthread_mutex_lock(&print_mutex);
65 			ksft_print_msg("%s: Time: get:%lld put:%lld us",
66 				       cmd_to_str(cmd), gup.get_delta_usec,
67 				       gup.put_delta_usec);
68 			if (gup.size != size)
69 				ksft_print_msg(", truncated (size: %lld)", gup.size);
70 			ksft_print_msg("\n");
71 			pthread_mutex_unlock(&print_mutex);
72 		}
73 	} else {
74 		gup.size = size;
75 		status = ioctl(gup_fd, cmd, &gup);
76 		if (status)
77 			goto return_;
78 
79 		pthread_mutex_lock(&print_mutex);
80 		ksft_print_msg("%s: done\n", cmd_to_str(cmd));
81 		if (gup.size != size)
82 			ksft_print_msg("Truncated (size: %lld)\n", gup.size);
83 		pthread_mutex_unlock(&print_mutex);
84 	}
85 
86 return_:
87 	ksft_test_result(!status, "ioctl status %d\n", status);
88 	return NULL;
89 }
90 
main(int argc,char ** argv)91 int main(int argc, char **argv)
92 {
93 	struct gup_test gup = { 0 };
94 	int filed, i, opt, nr_pages = 1, thp = -1, write = 1, nthreads = 1, ret;
95 	int flags = MAP_PRIVATE;
96 	char *file = "/dev/zero";
97 	pthread_t *tid;
98 	char *p;
99 
100 	while ((opt = getopt(argc, argv, "m:r:n:F:f:abcj:tTLUuwWSHpz")) != -1) {
101 		switch (opt) {
102 		case 'a':
103 			cmd = PIN_FAST_BENCHMARK;
104 			break;
105 		case 'b':
106 			cmd = PIN_BASIC_TEST;
107 			break;
108 		case 'L':
109 			cmd = PIN_LONGTERM_BENCHMARK;
110 			break;
111 		case 'c':
112 			cmd = DUMP_USER_PAGES_TEST;
113 			/*
114 			 * Dump page 0 (index 1). May be overridden later, by
115 			 * user's non-option arguments.
116 			 *
117 			 * .which_pages is zero-based, so that zero can mean "do
118 			 * nothing".
119 			 */
120 			gup.which_pages[0] = 1;
121 			break;
122 		case 'p':
123 			/* works only with DUMP_USER_PAGES_TEST */
124 			gup.test_flags |= GUP_TEST_FLAG_DUMP_PAGES_USE_PIN;
125 			break;
126 		case 'F':
127 			/* strtol, so you can pass flags in hex form */
128 			gup.gup_flags = strtol(optarg, 0, 0);
129 			break;
130 		case 'j':
131 			nthreads = atoi(optarg);
132 			break;
133 		case 'm':
134 			size = atoi(optarg) * MB;
135 			break;
136 		case 'r':
137 			repeats = atoi(optarg);
138 			break;
139 		case 'n':
140 			nr_pages = atoi(optarg);
141 			if (nr_pages < 0)
142 				nr_pages = size / psize();
143 			break;
144 		case 't':
145 			thp = 1;
146 			break;
147 		case 'T':
148 			thp = 0;
149 			break;
150 		case 'U':
151 			cmd = GUP_BASIC_TEST;
152 			break;
153 		case 'u':
154 			cmd = GUP_FAST_BENCHMARK;
155 			break;
156 		case 'w':
157 			write = 1;
158 			break;
159 		case 'W':
160 			write = 0;
161 			break;
162 		case 'f':
163 			file = optarg;
164 			break;
165 		case 'S':
166 			flags &= ~MAP_PRIVATE;
167 			flags |= MAP_SHARED;
168 			break;
169 		case 'H':
170 			flags |= (MAP_HUGETLB | MAP_ANONYMOUS);
171 			break;
172 		default:
173 			ksft_exit_fail_msg("Wrong argument\n");
174 		}
175 	}
176 
177 	if (optind < argc) {
178 		int extra_arg_count = 0;
179 		/*
180 		 * For example:
181 		 *
182 		 *   ./gup_test -c 0 1 0x1001
183 		 *
184 		 * ...to dump pages 0, 1, and 4097
185 		 */
186 
187 		while ((optind < argc) &&
188 		       (extra_arg_count < GUP_TEST_MAX_PAGES_TO_DUMP)) {
189 			/*
190 			 * Do the 1-based indexing here, so that the user can
191 			 * use normal 0-based indexing on the command line.
192 			 */
193 			long page_index = strtol(argv[optind], 0, 0) + 1;
194 
195 			gup.which_pages[extra_arg_count] = page_index;
196 			extra_arg_count++;
197 			optind++;
198 		}
199 	}
200 
201 	ksft_print_header();
202 	ksft_set_plan(nthreads);
203 
204 	filed = open(file, O_RDWR|O_CREAT, 0664);
205 	if (filed < 0)
206 		ksft_exit_fail_msg("Unable to open %s: %s\n", file, strerror(errno));
207 
208 	gup.nr_pages_per_call = nr_pages;
209 	if (write)
210 		gup.gup_flags |= FOLL_WRITE;
211 
212 	gup_fd = open(GUP_TEST_FILE, O_RDWR);
213 	if (gup_fd == -1) {
214 		switch (errno) {
215 		case EACCES:
216 			if (getuid())
217 				ksft_print_msg("Please run this test as root\n");
218 			break;
219 		case ENOENT:
220 			if (opendir("/sys/kernel/debug") == NULL)
221 				ksft_print_msg("mount debugfs at /sys/kernel/debug\n");
222 			ksft_print_msg("check if CONFIG_GUP_TEST is enabled in kernel config\n");
223 			break;
224 		default:
225 			ksft_print_msg("failed to open %s: %s\n", GUP_TEST_FILE, strerror(errno));
226 			break;
227 		}
228 		ksft_test_result_skip("Please run this test as root\n");
229 		ksft_exit_pass();
230 	}
231 
232 	p = mmap(NULL, size, PROT_READ | PROT_WRITE, flags, filed, 0);
233 	if (p == MAP_FAILED)
234 		ksft_exit_fail_msg("mmap: %s\n", strerror(errno));
235 	gup.addr = (unsigned long)p;
236 
237 	if (thp == 1)
238 		madvise(p, size, MADV_HUGEPAGE);
239 	else if (thp == 0)
240 		madvise(p, size, MADV_NOHUGEPAGE);
241 
242 	/* Fault them in here, from user space. */
243 	for (; (unsigned long)p < gup.addr + size; p += psize())
244 		p[0] = 0;
245 
246 	tid = malloc(sizeof(pthread_t) * nthreads);
247 	assert(tid);
248 	for (i = 0; i < nthreads; i++) {
249 		ret = pthread_create(&tid[i], NULL, gup_thread, &gup);
250 		assert(ret == 0);
251 	}
252 	for (i = 0; i < nthreads; i++) {
253 		ret = pthread_join(tid[i], NULL);
254 		assert(ret == 0);
255 	}
256 
257 	free(tid);
258 
259 	ksft_exit_pass();
260 }
261