tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1#include <fcntl.h>
2#include <stdio.h>
3#include <stdlib.h>
4#include <unistd.h>
5#include <sys/ioctl.h>
6#include <sys/mman.h>
7#include <sys/stat.h>
8#include <sys/types.h>
9#include <pthread.h>
10#include <assert.h>
11#include "../../../../mm/gup_test.h"
12
13#define MB (1UL << 20)
14#define PAGE_SIZE sysconf(_SC_PAGESIZE)
15
16/* Just the flags we need, copied from mm.h: */
17#define FOLL_WRITE 0x01 /* check pte is writable */
18#define FOLL_TOUCH 0x02 /* mark page accessed */
19
20static unsigned long cmd = GUP_FAST_BENCHMARK;
21static int gup_fd, repeats = 1;
22static unsigned long size = 128 * MB;
23/* Serialize prints */
24static pthread_mutex_t print_mutex = PTHREAD_MUTEX_INITIALIZER;
25
26static char *cmd_to_str(unsigned long cmd)
27{
28 switch (cmd) {
29 case GUP_FAST_BENCHMARK:
30 return "GUP_FAST_BENCHMARK";
31 case PIN_FAST_BENCHMARK:
32 return "PIN_FAST_BENCHMARK";
33 case PIN_LONGTERM_BENCHMARK:
34 return "PIN_LONGTERM_BENCHMARK";
35 case GUP_BASIC_TEST:
36 return "GUP_BASIC_TEST";
37 case PIN_BASIC_TEST:
38 return "PIN_BASIC_TEST";
39 case DUMP_USER_PAGES_TEST:
40 return "DUMP_USER_PAGES_TEST";
41 }
42 return "Unknown command";
43}
44
45void *gup_thread(void *data)
46{
47 struct gup_test gup = *(struct gup_test *)data;
48 int i;
49
50 /* Only report timing information on the *_BENCHMARK commands: */
51 if ((cmd == PIN_FAST_BENCHMARK) || (cmd == GUP_FAST_BENCHMARK) ||
52 (cmd == PIN_LONGTERM_BENCHMARK)) {
53 for (i = 0; i < repeats; i++) {
54 gup.size = size;
55 if (ioctl(gup_fd, cmd, &gup))
56 perror("ioctl"), exit(1);
57
58 pthread_mutex_lock(&print_mutex);
59 printf("%s: Time: get:%lld put:%lld us",
60 cmd_to_str(cmd), gup.get_delta_usec,
61 gup.put_delta_usec);
62 if (gup.size != size)
63 printf(", truncated (size: %lld)", gup.size);
64 printf("\n");
65 pthread_mutex_unlock(&print_mutex);
66 }
67 } else {
68 gup.size = size;
69 if (ioctl(gup_fd, cmd, &gup)) {
70 perror("ioctl");
71 exit(1);
72 }
73
74 pthread_mutex_lock(&print_mutex);
75 printf("%s: done\n", cmd_to_str(cmd));
76 if (gup.size != size)
77 printf("Truncated (size: %lld)\n", gup.size);
78 pthread_mutex_unlock(&print_mutex);
79 }
80
81 return NULL;
82}
83
84int main(int argc, char **argv)
85{
86 struct gup_test gup = { 0 };
87 int filed, i, opt, nr_pages = 1, thp = -1, write = 1, nthreads = 1, ret;
88 int flags = MAP_PRIVATE, touch = 0;
89 char *file = "/dev/zero";
90 pthread_t *tid;
91 char *p;
92
93 while ((opt = getopt(argc, argv, "m:r:n:F:f:abcj:tTLUuwWSHpz")) != -1) {
94 switch (opt) {
95 case 'a':
96 cmd = PIN_FAST_BENCHMARK;
97 break;
98 case 'b':
99 cmd = PIN_BASIC_TEST;
100 break;
101 case 'L':
102 cmd = PIN_LONGTERM_BENCHMARK;
103 break;
104 case 'c':
105 cmd = DUMP_USER_PAGES_TEST;
106 /*
107 * Dump page 0 (index 1). May be overridden later, by
108 * user's non-option arguments.
109 *
110 * .which_pages is zero-based, so that zero can mean "do
111 * nothing".
112 */
113 gup.which_pages[0] = 1;
114 break;
115 case 'p':
116 /* works only with DUMP_USER_PAGES_TEST */
117 gup.test_flags |= GUP_TEST_FLAG_DUMP_PAGES_USE_PIN;
118 break;
119 case 'F':
120 /* strtol, so you can pass flags in hex form */
121 gup.gup_flags = strtol(optarg, 0, 0);
122 break;
123 case 'j':
124 nthreads = atoi(optarg);
125 break;
126 case 'm':
127 size = atoi(optarg) * MB;
128 break;
129 case 'r':
130 repeats = atoi(optarg);
131 break;
132 case 'n':
133 nr_pages = atoi(optarg);
134 break;
135 case 't':
136 thp = 1;
137 break;
138 case 'T':
139 thp = 0;
140 break;
141 case 'U':
142 cmd = GUP_BASIC_TEST;
143 break;
144 case 'u':
145 cmd = GUP_FAST_BENCHMARK;
146 break;
147 case 'w':
148 write = 1;
149 break;
150 case 'W':
151 write = 0;
152 break;
153 case 'f':
154 file = optarg;
155 break;
156 case 'S':
157 flags &= ~MAP_PRIVATE;
158 flags |= MAP_SHARED;
159 break;
160 case 'H':
161 flags |= (MAP_HUGETLB | MAP_ANONYMOUS);
162 break;
163 case 'z':
164 /* fault pages in gup, do not fault in userland */
165 touch = 1;
166 break;
167 default:
168 return -1;
169 }
170 }
171
172 if (optind < argc) {
173 int extra_arg_count = 0;
174 /*
175 * For example:
176 *
177 * ./gup_test -c 0 1 0x1001
178 *
179 * ...to dump pages 0, 1, and 4097
180 */
181
182 while ((optind < argc) &&
183 (extra_arg_count < GUP_TEST_MAX_PAGES_TO_DUMP)) {
184 /*
185 * Do the 1-based indexing here, so that the user can
186 * use normal 0-based indexing on the command line.
187 */
188 long page_index = strtol(argv[optind], 0, 0) + 1;
189
190 gup.which_pages[extra_arg_count] = page_index;
191 extra_arg_count++;
192 optind++;
193 }
194 }
195
196 filed = open(file, O_RDWR|O_CREAT);
197 if (filed < 0) {
198 perror("open");
199 exit(filed);
200 }
201
202 gup.nr_pages_per_call = nr_pages;
203 if (write)
204 gup.gup_flags |= FOLL_WRITE;
205
206 gup_fd = open("/sys/kernel/debug/gup_test", O_RDWR);
207 if (gup_fd == -1) {
208 perror("open");
209 exit(1);
210 }
211
212 p = mmap(NULL, size, PROT_READ | PROT_WRITE, flags, filed, 0);
213 if (p == MAP_FAILED) {
214 perror("mmap");
215 exit(1);
216 }
217 gup.addr = (unsigned long)p;
218
219 if (thp == 1)
220 madvise(p, size, MADV_HUGEPAGE);
221 else if (thp == 0)
222 madvise(p, size, MADV_NOHUGEPAGE);
223
224 /*
225 * FOLL_TOUCH, in gup_test, is used as an either/or case: either
226 * fault pages in from the kernel via FOLL_TOUCH, or fault them
227 * in here, from user space. This allows comparison of performance
228 * between those two cases.
229 */
230 if (touch) {
231 gup.gup_flags |= FOLL_TOUCH;
232 } else {
233 for (; (unsigned long)p < gup.addr + size; p += PAGE_SIZE)
234 p[0] = 0;
235 }
236
237 tid = malloc(sizeof(pthread_t) * nthreads);
238 assert(tid);
239 for (i = 0; i < nthreads; i++) {
240 ret = pthread_create(&tid[i], NULL, gup_thread, &gup);
241 assert(ret == 0);
242 }
243 for (i = 0; i < nthreads; i++) {
244 ret = pthread_join(tid[i], NULL);
245 assert(ret == 0);
246 }
247 free(tid);
248
249 return 0;
250}