1 /* SPDX-License-Identifier: BSD-3-Clause
2 * Copyright(c) 2010-2014 Intel Corporation
3 */
4
5 #include <string.h>
6 #include <sys/types.h>
7 #include <sys/file.h>
8 #include <dirent.h>
9 #include <fcntl.h>
10 #include <stdint.h>
11 #include <stdlib.h>
12 #include <stdio.h>
13 #include <fnmatch.h>
14 #include <inttypes.h>
15 #include <stdarg.h>
16 #include <unistd.h>
17 #include <errno.h>
18 #include <sys/mman.h>
19 #include <sys/queue.h>
20 #include <sys/stat.h>
21
22 #include <linux/mman.h> /* for hugetlb-related flags */
23
24 #include <rte_memory.h>
25 #include <rte_eal.h>
26 #include <rte_launch.h>
27 #include <rte_per_lcore.h>
28 #include <rte_lcore.h>
29 #include <rte_debug.h>
30 #include <rte_log.h>
31 #include <rte_common.h>
32 #include "rte_string_fns.h"
33
34 #include "eal_private.h"
35 #include "eal_internal_cfg.h"
36 #include "eal_hugepages.h"
37 #include "eal_filesystem.h"
38
39 static const char sys_dir_path[] = "/sys/kernel/mm/hugepages";
40 static const char sys_pages_numa_dir_path[] = "/sys/devices/system/node";
41
42 /*
43 * Uses mmap to create a shared memory area for storage of data
44 * Used in this file to store the hugepage file map on disk
45 */
46 static void *
map_shared_memory(const char * filename,const size_t mem_size,int flags)47 map_shared_memory(const char *filename, const size_t mem_size, int flags)
48 {
49 void *retval;
50 int fd = open(filename, flags, 0600);
51 if (fd < 0)
52 return NULL;
53 if (ftruncate(fd, mem_size) < 0) {
54 close(fd);
55 return NULL;
56 }
57 retval = mmap(NULL, mem_size, PROT_READ | PROT_WRITE,
58 MAP_SHARED, fd, 0);
59 close(fd);
60 return retval;
61 }
62
63 static void *
open_shared_memory(const char * filename,const size_t mem_size)64 open_shared_memory(const char *filename, const size_t mem_size)
65 {
66 return map_shared_memory(filename, mem_size, O_RDWR);
67 }
68
69 static void *
create_shared_memory(const char * filename,const size_t mem_size)70 create_shared_memory(const char *filename, const size_t mem_size)
71 {
72 return map_shared_memory(filename, mem_size, O_RDWR | O_CREAT);
73 }
74
get_hp_sysfs_value(const char * subdir,const char * file,unsigned long * val)75 static int get_hp_sysfs_value(const char *subdir, const char *file, unsigned long *val)
76 {
77 char path[PATH_MAX];
78
79 snprintf(path, sizeof(path), "%s/%s/%s",
80 sys_dir_path, subdir, file);
81 return eal_parse_sysfs_value(path, val);
82 }
83
84 /* this function is only called from eal_hugepage_info_init which itself
85 * is only called from a primary process */
86 static uint32_t
get_num_hugepages(const char * subdir)87 get_num_hugepages(const char *subdir)
88 {
89 unsigned long resv_pages, num_pages, over_pages, surplus_pages;
90 const char *nr_hp_file = "free_hugepages";
91 const char *nr_rsvd_file = "resv_hugepages";
92 const char *nr_over_file = "nr_overcommit_hugepages";
93 const char *nr_splus_file = "surplus_hugepages";
94
95 /* first, check how many reserved pages kernel reports */
96 if (get_hp_sysfs_value(subdir, nr_rsvd_file, &resv_pages) < 0)
97 return 0;
98
99 if (get_hp_sysfs_value(subdir, nr_hp_file, &num_pages) < 0)
100 return 0;
101
102 if (get_hp_sysfs_value(subdir, nr_over_file, &over_pages) < 0)
103 over_pages = 0;
104
105 if (get_hp_sysfs_value(subdir, nr_splus_file, &surplus_pages) < 0)
106 surplus_pages = 0;
107
108 /* adjust num_pages */
109 if (num_pages >= resv_pages)
110 num_pages -= resv_pages;
111 else if (resv_pages)
112 num_pages = 0;
113
114 if (over_pages >= surplus_pages)
115 over_pages -= surplus_pages;
116 else
117 over_pages = 0;
118
119 if (num_pages == 0 && over_pages == 0)
120 RTE_LOG(WARNING, EAL, "No available hugepages reported in %s\n",
121 subdir);
122
123 num_pages += over_pages;
124 if (num_pages < over_pages) /* overflow */
125 num_pages = UINT32_MAX;
126
127 /* we want to return a uint32_t and more than this looks suspicious
128 * anyway ... */
129 if (num_pages > UINT32_MAX)
130 num_pages = UINT32_MAX;
131
132 return num_pages;
133 }
134
135 static uint32_t
get_num_hugepages_on_node(const char * subdir,unsigned int socket)136 get_num_hugepages_on_node(const char *subdir, unsigned int socket)
137 {
138 char path[PATH_MAX], socketpath[PATH_MAX];
139 DIR *socketdir;
140 unsigned long num_pages = 0;
141 const char *nr_hp_file = "free_hugepages";
142
143 snprintf(socketpath, sizeof(socketpath), "%s/node%u/hugepages",
144 sys_pages_numa_dir_path, socket);
145
146 socketdir = opendir(socketpath);
147 if (socketdir) {
148 /* Keep calm and carry on */
149 closedir(socketdir);
150 } else {
151 /* Can't find socket dir, so ignore it */
152 return 0;
153 }
154
155 snprintf(path, sizeof(path), "%s/%s/%s",
156 socketpath, subdir, nr_hp_file);
157 if (eal_parse_sysfs_value(path, &num_pages) < 0)
158 return 0;
159
160 if (num_pages == 0)
161 RTE_LOG(WARNING, EAL, "No free hugepages reported in %s\n",
162 subdir);
163
164 /*
165 * we want to return a uint32_t and more than this looks suspicious
166 * anyway ...
167 */
168 if (num_pages > UINT32_MAX)
169 num_pages = UINT32_MAX;
170
171 return num_pages;
172 }
173
174 static uint64_t
get_default_hp_size(void)175 get_default_hp_size(void)
176 {
177 const char proc_meminfo[] = "/proc/meminfo";
178 const char str_hugepagesz[] = "Hugepagesize:";
179 unsigned hugepagesz_len = sizeof(str_hugepagesz) - 1;
180 char buffer[256];
181 unsigned long long size = 0;
182
183 FILE *fd = fopen(proc_meminfo, "r");
184 if (fd == NULL)
185 rte_panic("Cannot open %s\n", proc_meminfo);
186 while(fgets(buffer, sizeof(buffer), fd)){
187 if (strncmp(buffer, str_hugepagesz, hugepagesz_len) == 0){
188 size = rte_str_to_size(&buffer[hugepagesz_len]);
189 break;
190 }
191 }
192 fclose(fd);
193 if (size == 0)
194 rte_panic("Cannot get default hugepage size from %s\n", proc_meminfo);
195 return size;
196 }
197
198 static int
get_hugepage_dir(uint64_t hugepage_sz,char * hugedir,int len)199 get_hugepage_dir(uint64_t hugepage_sz, char *hugedir, int len)
200 {
201 enum proc_mount_fieldnames {
202 DEVICE = 0,
203 MOUNTPT,
204 FSTYPE,
205 OPTIONS,
206 _FIELDNAME_MAX
207 };
208 static uint64_t default_size = 0;
209 const char proc_mounts[] = "/proc/mounts";
210 const char hugetlbfs_str[] = "hugetlbfs";
211 const size_t htlbfs_str_len = sizeof(hugetlbfs_str) - 1;
212 const char pagesize_opt[] = "pagesize=";
213 const size_t pagesize_opt_len = sizeof(pagesize_opt) - 1;
214 const char split_tok = ' ';
215 char *splitstr[_FIELDNAME_MAX];
216 char buf[BUFSIZ];
217 int retval = -1;
218 const struct internal_config *internal_conf =
219 eal_get_internal_configuration();
220
221 FILE *fd = fopen(proc_mounts, "r");
222 if (fd == NULL)
223 rte_panic("Cannot open %s\n", proc_mounts);
224
225 if (default_size == 0)
226 default_size = get_default_hp_size();
227
228 while (fgets(buf, sizeof(buf), fd)){
229 if (rte_strsplit(buf, sizeof(buf), splitstr, _FIELDNAME_MAX,
230 split_tok) != _FIELDNAME_MAX) {
231 RTE_LOG(ERR, EAL, "Error parsing %s\n", proc_mounts);
232 break; /* return NULL */
233 }
234
235 /* we have a specified --huge-dir option, only examine that dir */
236 if (internal_conf->hugepage_dir != NULL &&
237 strcmp(splitstr[MOUNTPT], internal_conf->hugepage_dir) != 0)
238 continue;
239
240 if (strncmp(splitstr[FSTYPE], hugetlbfs_str, htlbfs_str_len) == 0){
241 const char *pagesz_str = strstr(splitstr[OPTIONS], pagesize_opt);
242
243 /* if no explicit page size, the default page size is compared */
244 if (pagesz_str == NULL){
245 if (hugepage_sz == default_size){
246 strlcpy(hugedir, splitstr[MOUNTPT], len);
247 retval = 0;
248 break;
249 }
250 }
251 /* there is an explicit page size, so check it */
252 else {
253 uint64_t pagesz = rte_str_to_size(&pagesz_str[pagesize_opt_len]);
254 if (pagesz == hugepage_sz) {
255 strlcpy(hugedir, splitstr[MOUNTPT], len);
256 retval = 0;
257 break;
258 }
259 }
260 } /* end if strncmp hugetlbfs */
261 } /* end while fgets */
262
263 fclose(fd);
264 return retval;
265 }
266
267 /*
268 * Clear the hugepage directory of whatever hugepage files
269 * there are. Checks if the file is locked (i.e.
270 * if it's in use by another DPDK process).
271 */
272 static int
clear_hugedir(const char * hugedir)273 clear_hugedir(const char * hugedir)
274 {
275 DIR *dir;
276 struct dirent *dirent;
277 int dir_fd, fd, lck_result;
278 const char filter[] = "*map_*"; /* matches hugepage files */
279
280 /* open directory */
281 dir = opendir(hugedir);
282 if (!dir) {
283 RTE_LOG(ERR, EAL, "Unable to open hugepage directory %s\n",
284 hugedir);
285 goto error;
286 }
287 dir_fd = dirfd(dir);
288
289 dirent = readdir(dir);
290 if (!dirent) {
291 RTE_LOG(ERR, EAL, "Unable to read hugepage directory %s\n",
292 hugedir);
293 goto error;
294 }
295
296 while(dirent != NULL){
297 /* skip files that don't match the hugepage pattern */
298 if (fnmatch(filter, dirent->d_name, 0) > 0) {
299 dirent = readdir(dir);
300 continue;
301 }
302
303 /* try and lock the file */
304 fd = openat(dir_fd, dirent->d_name, O_RDONLY);
305
306 /* skip to next file */
307 if (fd == -1) {
308 dirent = readdir(dir);
309 continue;
310 }
311
312 /* non-blocking lock */
313 lck_result = flock(fd, LOCK_EX | LOCK_NB);
314
315 /* if lock succeeds, remove the file */
316 if (lck_result != -1)
317 unlinkat(dir_fd, dirent->d_name, 0);
318 close (fd);
319 dirent = readdir(dir);
320 }
321
322 closedir(dir);
323 return 0;
324
325 error:
326 if (dir)
327 closedir(dir);
328
329 RTE_LOG(ERR, EAL, "Error while clearing hugepage dir: %s\n",
330 strerror(errno));
331
332 return -1;
333 }
334
335 static int
compare_hpi(const void * a,const void * b)336 compare_hpi(const void *a, const void *b)
337 {
338 const struct hugepage_info *hpi_a = a;
339 const struct hugepage_info *hpi_b = b;
340
341 return hpi_b->hugepage_sz - hpi_a->hugepage_sz;
342 }
343
344 static void
calc_num_pages(struct hugepage_info * hpi,struct dirent * dirent)345 calc_num_pages(struct hugepage_info *hpi, struct dirent *dirent)
346 {
347 uint64_t total_pages = 0;
348 unsigned int i;
349 const struct internal_config *internal_conf =
350 eal_get_internal_configuration();
351
352 /*
353 * first, try to put all hugepages into relevant sockets, but
354 * if first attempts fails, fall back to collecting all pages
355 * in one socket and sorting them later
356 */
357 total_pages = 0;
358 /* we also don't want to do this for legacy init */
359 if (!internal_conf->legacy_mem)
360 for (i = 0; i < rte_socket_count(); i++) {
361 int socket = rte_socket_id_by_idx(i);
362 unsigned int num_pages =
363 get_num_hugepages_on_node(
364 dirent->d_name, socket);
365 hpi->num_pages[socket] = num_pages;
366 total_pages += num_pages;
367 }
368 /*
369 * we failed to sort memory from the get go, so fall
370 * back to old way
371 */
372 if (total_pages == 0) {
373 hpi->num_pages[0] = get_num_hugepages(dirent->d_name);
374
375 #ifndef RTE_ARCH_64
376 /* for 32-bit systems, limit number of hugepages to
377 * 1GB per page size */
378 hpi->num_pages[0] = RTE_MIN(hpi->num_pages[0],
379 RTE_PGSIZE_1G / hpi->hugepage_sz);
380 #endif
381 }
382 }
383
384 static int
hugepage_info_init(void)385 hugepage_info_init(void)
386 { const char dirent_start_text[] = "hugepages-";
387 const size_t dirent_start_len = sizeof(dirent_start_text) - 1;
388 unsigned int i, num_sizes = 0;
389 DIR *dir;
390 struct dirent *dirent;
391 struct internal_config *internal_conf =
392 eal_get_internal_configuration();
393
394 dir = opendir(sys_dir_path);
395 if (dir == NULL) {
396 RTE_LOG(ERR, EAL,
397 "Cannot open directory %s to read system hugepage info\n",
398 sys_dir_path);
399 return -1;
400 }
401
402 for (dirent = readdir(dir); dirent != NULL; dirent = readdir(dir)) {
403 struct hugepage_info *hpi;
404
405 if (strncmp(dirent->d_name, dirent_start_text,
406 dirent_start_len) != 0)
407 continue;
408
409 if (num_sizes >= MAX_HUGEPAGE_SIZES)
410 break;
411
412 hpi = &internal_conf->hugepage_info[num_sizes];
413 hpi->hugepage_sz =
414 rte_str_to_size(&dirent->d_name[dirent_start_len]);
415
416 /* first, check if we have a mountpoint */
417 if (get_hugepage_dir(hpi->hugepage_sz,
418 hpi->hugedir, sizeof(hpi->hugedir)) < 0) {
419 uint32_t num_pages;
420
421 num_pages = get_num_hugepages(dirent->d_name);
422 if (num_pages > 0)
423 RTE_LOG(NOTICE, EAL,
424 "%" PRIu32 " hugepages of size "
425 "%" PRIu64 " reserved, but no mounted "
426 "hugetlbfs found for that size\n",
427 num_pages, hpi->hugepage_sz);
428 /* if we have kernel support for reserving hugepages
429 * through mmap, and we're in in-memory mode, treat this
430 * page size as valid. we cannot be in legacy mode at
431 * this point because we've checked this earlier in the
432 * init process.
433 */
434 #ifdef MAP_HUGE_SHIFT
435 if (internal_conf->in_memory) {
436 RTE_LOG(DEBUG, EAL, "In-memory mode enabled, "
437 "hugepages of size %" PRIu64 " bytes "
438 "will be allocated anonymously\n",
439 hpi->hugepage_sz);
440 calc_num_pages(hpi, dirent);
441 num_sizes++;
442 }
443 #endif
444 continue;
445 }
446
447 /* try to obtain a writelock */
448 hpi->lock_descriptor = open(hpi->hugedir, O_RDONLY);
449
450 /* if blocking lock failed */
451 if (flock(hpi->lock_descriptor, LOCK_EX) == -1) {
452 RTE_LOG(CRIT, EAL,
453 "Failed to lock hugepage directory!\n");
454 break;
455 }
456 /* clear out the hugepages dir from unused pages */
457 if (clear_hugedir(hpi->hugedir) == -1)
458 break;
459
460 calc_num_pages(hpi, dirent);
461
462 num_sizes++;
463 }
464 closedir(dir);
465
466 /* something went wrong, and we broke from the for loop above */
467 if (dirent != NULL)
468 return -1;
469
470 internal_conf->num_hugepage_sizes = num_sizes;
471
472 /* sort the page directory entries by size, largest to smallest */
473 qsort(&internal_conf->hugepage_info[0], num_sizes,
474 sizeof(internal_conf->hugepage_info[0]), compare_hpi);
475
476 /* now we have all info, check we have at least one valid size */
477 for (i = 0; i < num_sizes; i++) {
478 /* pages may no longer all be on socket 0, so check all */
479 unsigned int j, num_pages = 0;
480 struct hugepage_info *hpi = &internal_conf->hugepage_info[i];
481
482 for (j = 0; j < RTE_MAX_NUMA_NODES; j++)
483 num_pages += hpi->num_pages[j];
484 if (num_pages > 0)
485 return 0;
486 }
487
488 /* no valid hugepage mounts available, return error */
489 return -1;
490 }
491
492 /*
493 * when we initialize the hugepage info, everything goes
494 * to socket 0 by default. it will later get sorted by memory
495 * initialization procedure.
496 */
497 int
eal_hugepage_info_init(void)498 eal_hugepage_info_init(void)
499 {
500 struct hugepage_info *hpi, *tmp_hpi;
501 unsigned int i;
502 struct internal_config *internal_conf =
503 eal_get_internal_configuration();
504
505 if (hugepage_info_init() < 0)
506 return -1;
507
508 /* for no shared files mode, we're done */
509 if (internal_conf->no_shconf)
510 return 0;
511
512 hpi = &internal_conf->hugepage_info[0];
513
514 tmp_hpi = create_shared_memory(eal_hugepage_info_path(),
515 sizeof(internal_conf->hugepage_info));
516 if (tmp_hpi == NULL) {
517 RTE_LOG(ERR, EAL, "Failed to create shared memory!\n");
518 return -1;
519 }
520
521 memcpy(tmp_hpi, hpi, sizeof(internal_conf->hugepage_info));
522
523 /* we've copied file descriptors along with everything else, but they
524 * will be invalid in secondary process, so overwrite them
525 */
526 for (i = 0; i < RTE_DIM(internal_conf->hugepage_info); i++) {
527 struct hugepage_info *tmp = &tmp_hpi[i];
528 tmp->lock_descriptor = -1;
529 }
530
531 if (munmap(tmp_hpi, sizeof(internal_conf->hugepage_info)) < 0) {
532 RTE_LOG(ERR, EAL, "Failed to unmap shared memory!\n");
533 return -1;
534 }
535 return 0;
536 }
537
eal_hugepage_info_read(void)538 int eal_hugepage_info_read(void)
539 {
540 struct internal_config *internal_conf =
541 eal_get_internal_configuration();
542 struct hugepage_info *hpi = &internal_conf->hugepage_info[0];
543 struct hugepage_info *tmp_hpi;
544
545 tmp_hpi = open_shared_memory(eal_hugepage_info_path(),
546 sizeof(internal_conf->hugepage_info));
547 if (tmp_hpi == NULL) {
548 RTE_LOG(ERR, EAL, "Failed to open shared memory!\n");
549 return -1;
550 }
551
552 memcpy(hpi, tmp_hpi, sizeof(internal_conf->hugepage_info));
553
554 if (munmap(tmp_hpi, sizeof(internal_conf->hugepage_info)) < 0) {
555 RTE_LOG(ERR, EAL, "Failed to unmap shared memory!\n");
556 return -1;
557 }
558 return 0;
559 }
560