1 /* SPDX-License-Identifier: BSD-3-Clause
2 * Copyright(c) 2010-2014 Intel Corporation
3 */
4
5 #include <string.h>
6 #include <sys/file.h>
7 #include <dirent.h>
8 #include <fcntl.h>
9 #include <stdint.h>
10 #include <stdlib.h>
11 #include <stdio.h>
12 #include <fnmatch.h>
13 #include <inttypes.h>
14 #include <unistd.h>
15 #include <errno.h>
16 #include <sys/mman.h>
17 #include <sys/stat.h>
18
19 #include <linux/mman.h> /* for hugetlb-related flags */
20
21 #include <rte_lcore.h>
22 #include <rte_debug.h>
23 #include <rte_log.h>
24 #include <rte_common.h>
25 #include "rte_string_fns.h"
26
27 #include "eal_private.h"
28 #include "eal_internal_cfg.h"
29 #include "eal_hugepages.h"
30 #include "eal_filesystem.h"
31
32 static const char sys_dir_path[] = "/sys/kernel/mm/hugepages";
33 static const char sys_pages_numa_dir_path[] = "/sys/devices/system/node";
34
35 /*
36 * Uses mmap to create a shared memory area for storage of data
37 * Used in this file to store the hugepage file map on disk
38 */
39 static void *
map_shared_memory(const char * filename,const size_t mem_size,int flags)40 map_shared_memory(const char *filename, const size_t mem_size, int flags)
41 {
42 void *retval;
43 int fd = open(filename, flags, 0600);
44 if (fd < 0)
45 return NULL;
46 if (ftruncate(fd, mem_size) < 0) {
47 close(fd);
48 return NULL;
49 }
50 retval = mmap(NULL, mem_size, PROT_READ | PROT_WRITE,
51 MAP_SHARED, fd, 0);
52 close(fd);
53 return retval == MAP_FAILED ? NULL : retval;
54 }
55
56 static void *
open_shared_memory(const char * filename,const size_t mem_size)57 open_shared_memory(const char *filename, const size_t mem_size)
58 {
59 return map_shared_memory(filename, mem_size, O_RDWR);
60 }
61
62 static void *
create_shared_memory(const char * filename,const size_t mem_size)63 create_shared_memory(const char *filename, const size_t mem_size)
64 {
65 return map_shared_memory(filename, mem_size, O_RDWR | O_CREAT);
66 }
67
get_hp_sysfs_value(const char * subdir,const char * file,unsigned long * val)68 static int get_hp_sysfs_value(const char *subdir, const char *file, unsigned long *val)
69 {
70 char path[PATH_MAX];
71
72 snprintf(path, sizeof(path), "%s/%s/%s",
73 sys_dir_path, subdir, file);
74 return eal_parse_sysfs_value(path, val);
75 }
76
77 /* this function is only called from eal_hugepage_info_init which itself
78 * is only called from a primary process */
79 static uint32_t
get_num_hugepages(const char * subdir,size_t sz,unsigned int reusable_pages)80 get_num_hugepages(const char *subdir, size_t sz, unsigned int reusable_pages)
81 {
82 unsigned long resv_pages, num_pages, over_pages, surplus_pages;
83 const char *nr_hp_file = "free_hugepages";
84 const char *nr_rsvd_file = "resv_hugepages";
85 const char *nr_over_file = "nr_overcommit_hugepages";
86 const char *nr_splus_file = "surplus_hugepages";
87
88 /* first, check how many reserved pages kernel reports */
89 if (get_hp_sysfs_value(subdir, nr_rsvd_file, &resv_pages) < 0)
90 return 0;
91
92 if (get_hp_sysfs_value(subdir, nr_hp_file, &num_pages) < 0)
93 return 0;
94
95 if (get_hp_sysfs_value(subdir, nr_over_file, &over_pages) < 0)
96 over_pages = 0;
97
98 if (get_hp_sysfs_value(subdir, nr_splus_file, &surplus_pages) < 0)
99 surplus_pages = 0;
100
101 /* adjust num_pages */
102 if (num_pages >= resv_pages)
103 num_pages -= resv_pages;
104 else if (resv_pages)
105 num_pages = 0;
106
107 if (over_pages >= surplus_pages)
108 over_pages -= surplus_pages;
109 else
110 over_pages = 0;
111
112 if (num_pages == 0 && over_pages == 0 && reusable_pages)
113 EAL_LOG(WARNING, "No available %zu kB hugepages reported",
114 sz >> 10);
115
116 num_pages += over_pages;
117 if (num_pages < over_pages) /* overflow */
118 num_pages = UINT32_MAX;
119
120 num_pages += reusable_pages;
121 if (num_pages < reusable_pages) /* overflow */
122 num_pages = UINT32_MAX;
123
124 /* we want to return a uint32_t and more than this looks suspicious
125 * anyway ... */
126 if (num_pages > UINT32_MAX)
127 num_pages = UINT32_MAX;
128
129 return num_pages;
130 }
131
132 static uint32_t
get_num_hugepages_on_node(const char * subdir,unsigned int socket,size_t sz)133 get_num_hugepages_on_node(const char *subdir, unsigned int socket, size_t sz)
134 {
135 char path[PATH_MAX], socketpath[PATH_MAX];
136 DIR *socketdir;
137 unsigned long num_pages = 0;
138 const char *nr_hp_file = "free_hugepages";
139
140 snprintf(socketpath, sizeof(socketpath), "%s/node%u/hugepages",
141 sys_pages_numa_dir_path, socket);
142
143 socketdir = opendir(socketpath);
144 if (socketdir) {
145 /* Keep calm and carry on */
146 closedir(socketdir);
147 } else {
148 /* Can't find socket dir, so ignore it */
149 return 0;
150 }
151
152 snprintf(path, sizeof(path), "%s/%s/%s",
153 socketpath, subdir, nr_hp_file);
154 if (eal_parse_sysfs_value(path, &num_pages) < 0)
155 return 0;
156
157 if (num_pages == 0)
158 EAL_LOG(WARNING, "No free %zu kB hugepages reported on node %u",
159 sz >> 10, socket);
160
161 /*
162 * we want to return a uint32_t and more than this looks suspicious
163 * anyway ...
164 */
165 if (num_pages > UINT32_MAX)
166 num_pages = UINT32_MAX;
167
168 return num_pages;
169 }
170
171 static uint64_t
get_default_hp_size(void)172 get_default_hp_size(void)
173 {
174 const char proc_meminfo[] = "/proc/meminfo";
175 const char str_hugepagesz[] = "Hugepagesize:";
176 unsigned hugepagesz_len = sizeof(str_hugepagesz) - 1;
177 char buffer[256];
178 unsigned long long size = 0;
179
180 FILE *fd = fopen(proc_meminfo, "r");
181 if (fd == NULL)
182 rte_panic("Cannot open %s\n", proc_meminfo);
183 while(fgets(buffer, sizeof(buffer), fd)){
184 if (strncmp(buffer, str_hugepagesz, hugepagesz_len) == 0){
185 size = rte_str_to_size(&buffer[hugepagesz_len]);
186 break;
187 }
188 }
189 fclose(fd);
190 if (size == 0)
191 rte_panic("Cannot get default hugepage size from %s\n", proc_meminfo);
192 return size;
193 }
194
195 static int
get_hugepage_dir(uint64_t hugepage_sz,char * hugedir,int len)196 get_hugepage_dir(uint64_t hugepage_sz, char *hugedir, int len)
197 {
198 enum proc_mount_fieldnames {
199 DEVICE = 0,
200 MOUNTPT,
201 FSTYPE,
202 OPTIONS,
203 _FIELDNAME_MAX
204 };
205 static uint64_t default_size = 0;
206 const char proc_mounts[] = "/proc/mounts";
207 const char hugetlbfs_str[] = "hugetlbfs";
208 const size_t htlbfs_str_len = sizeof(hugetlbfs_str) - 1;
209 const char pagesize_opt[] = "pagesize=";
210 const size_t pagesize_opt_len = sizeof(pagesize_opt) - 1;
211 const char split_tok = ' ';
212 char *splitstr[_FIELDNAME_MAX];
213 char found[PATH_MAX] = "";
214 char buf[BUFSIZ];
215 const struct internal_config *internal_conf =
216 eal_get_internal_configuration();
217 const size_t hugepage_dir_len = (internal_conf->hugepage_dir != NULL) ?
218 strlen(internal_conf->hugepage_dir) : 0;
219 struct stat st;
220
221 /*
222 * If the specified dir doesn't exist, we can't match it.
223 */
224 if (internal_conf->hugepage_dir != NULL &&
225 stat(internal_conf->hugepage_dir, &st) != 0) {
226 return -1;
227 }
228
229 FILE *fd = fopen(proc_mounts, "r");
230 if (fd == NULL)
231 rte_panic("Cannot open %s\n", proc_mounts);
232
233 if (default_size == 0)
234 default_size = get_default_hp_size();
235
236 while (fgets(buf, sizeof(buf), fd)){
237 const char *pagesz_str;
238 size_t mountpt_len = 0;
239
240 if (rte_strsplit(buf, sizeof(buf), splitstr, _FIELDNAME_MAX,
241 split_tok) != _FIELDNAME_MAX) {
242 EAL_LOG(ERR, "Error parsing %s", proc_mounts);
243 break; /* return NULL */
244 }
245
246 if (strncmp(splitstr[FSTYPE], hugetlbfs_str, htlbfs_str_len) != 0)
247 continue;
248
249 pagesz_str = strstr(splitstr[OPTIONS], pagesize_opt);
250
251 /* if no explicit page size, the default page size is compared */
252 if (pagesz_str == NULL) {
253 if (hugepage_sz != default_size)
254 continue;
255 }
256 /* there is an explicit page size, so check it */
257 else {
258 uint64_t pagesz = rte_str_to_size(&pagesz_str[pagesize_opt_len]);
259 if (pagesz != hugepage_sz)
260 continue;
261 }
262
263 /*
264 * If no --huge-dir option has been given, we're done.
265 */
266 if (internal_conf->hugepage_dir == NULL) {
267 strlcpy(found, splitstr[MOUNTPT], len);
268 break;
269 }
270
271 mountpt_len = strlen(splitstr[MOUNTPT]);
272
273 /*
274 * Ignore any mount that doesn't contain the --huge-dir directory
275 * or where mount point is not a parent path of --huge-dir
276 */
277 if (strncmp(internal_conf->hugepage_dir, splitstr[MOUNTPT],
278 mountpt_len) != 0 ||
279 (hugepage_dir_len > mountpt_len &&
280 internal_conf->hugepage_dir[mountpt_len] != '/')) {
281 continue;
282 }
283
284 /*
285 * We found a match, but only prefer it if it's a longer match
286 * (so /mnt/1 is preferred over /mnt for matching /mnt/1/2)).
287 */
288 if (mountpt_len > strlen(found))
289 strlcpy(found, splitstr[MOUNTPT], len);
290 } /* end while fgets */
291
292 fclose(fd);
293
294 if (found[0] != '\0') {
295 /* If needed, return the requested dir, not the mount point. */
296 strlcpy(hugedir, internal_conf->hugepage_dir != NULL ?
297 internal_conf->hugepage_dir : found, len);
298 return 0;
299 }
300
301 return -1;
302 }
303
304 struct walk_hugedir_data {
305 int dir_fd;
306 int file_fd;
307 const char *file_name;
308 void *user_data;
309 };
310
311 typedef void (walk_hugedir_t)(const struct walk_hugedir_data *whd);
312
313 /*
314 * Search the hugepage directory for whatever hugepage files there are.
315 * Check if the file is in use by another DPDK process.
316 * If not, execute a callback on it.
317 */
318 static int
walk_hugedir(const char * hugedir,walk_hugedir_t * cb,void * user_data)319 walk_hugedir(const char *hugedir, walk_hugedir_t *cb, void *user_data)
320 {
321 DIR *dir;
322 struct dirent *dirent;
323 int dir_fd, fd, lck_result;
324 const char filter[] = "*map_*"; /* matches hugepage files */
325
326 dir = opendir(hugedir);
327 if (!dir) {
328 EAL_LOG(ERR, "Unable to open hugepage directory %s",
329 hugedir);
330 goto error;
331 }
332 dir_fd = dirfd(dir);
333
334 dirent = readdir(dir);
335 if (!dirent) {
336 EAL_LOG(ERR, "Unable to read hugepage directory %s",
337 hugedir);
338 goto error;
339 }
340
341 while (dirent != NULL) {
342 /* skip files that don't match the hugepage pattern */
343 if (fnmatch(filter, dirent->d_name, 0) > 0) {
344 dirent = readdir(dir);
345 continue;
346 }
347
348 /* try and lock the file */
349 fd = openat(dir_fd, dirent->d_name, O_RDONLY);
350
351 /* skip to next file */
352 if (fd == -1) {
353 dirent = readdir(dir);
354 continue;
355 }
356
357 /* non-blocking lock */
358 lck_result = flock(fd, LOCK_EX | LOCK_NB);
359
360 /* if lock succeeds, execute callback */
361 if (lck_result != -1)
362 cb(&(struct walk_hugedir_data){
363 .dir_fd = dir_fd,
364 .file_fd = fd,
365 .file_name = dirent->d_name,
366 .user_data = user_data,
367 });
368
369 close (fd);
370 dirent = readdir(dir);
371 }
372
373 closedir(dir);
374 return 0;
375
376 error:
377 if (dir)
378 closedir(dir);
379
380 EAL_LOG(ERR, "Error while walking hugepage dir: %s",
381 strerror(errno));
382
383 return -1;
384 }
385
386 static void
clear_hugedir_cb(const struct walk_hugedir_data * whd)387 clear_hugedir_cb(const struct walk_hugedir_data *whd)
388 {
389 unlinkat(whd->dir_fd, whd->file_name, 0);
390 }
391
392 /* Remove hugepage files not used by other DPDK processes from a directory. */
393 static int
clear_hugedir(const char * hugedir)394 clear_hugedir(const char *hugedir)
395 {
396 return walk_hugedir(hugedir, clear_hugedir_cb, NULL);
397 }
398
399 static void
inspect_hugedir_cb(const struct walk_hugedir_data * whd)400 inspect_hugedir_cb(const struct walk_hugedir_data *whd)
401 {
402 uint64_t *total_size = whd->user_data;
403 struct stat st;
404
405 if (fstat(whd->file_fd, &st) < 0)
406 EAL_LOG(DEBUG, "%s(): stat(\"%s\") failed: %s",
407 __func__, whd->file_name, strerror(errno));
408 else
409 (*total_size) += st.st_size;
410 }
411
412 /*
413 * Count the total size in bytes of all files in the directory
414 * not mapped by other DPDK process.
415 */
416 static int
inspect_hugedir(const char * hugedir,uint64_t * total_size)417 inspect_hugedir(const char *hugedir, uint64_t *total_size)
418 {
419 return walk_hugedir(hugedir, inspect_hugedir_cb, total_size);
420 }
421
422 static int
compare_hpi(const void * a,const void * b)423 compare_hpi(const void *a, const void *b)
424 {
425 const struct hugepage_info *hpi_a = a;
426 const struct hugepage_info *hpi_b = b;
427
428 return hpi_b->hugepage_sz - hpi_a->hugepage_sz;
429 }
430
431 static void
calc_num_pages(struct hugepage_info * hpi,struct dirent * dirent,unsigned int reusable_pages)432 calc_num_pages(struct hugepage_info *hpi, struct dirent *dirent,
433 unsigned int reusable_pages)
434 {
435 uint64_t total_pages = 0;
436 unsigned int i;
437 const struct internal_config *internal_conf =
438 eal_get_internal_configuration();
439
440 /*
441 * first, try to put all hugepages into relevant sockets, but
442 * if first attempts fails, fall back to collecting all pages
443 * in one socket and sorting them later
444 */
445 total_pages = 0;
446
447 /*
448 * We also don't want to do this for legacy init.
449 * When there are hugepage files to reuse it is unknown
450 * what NUMA node the pages are on.
451 * This could be determined by mapping,
452 * but it is precisely what hugepage file reuse is trying to avoid.
453 */
454 if (!internal_conf->legacy_mem && reusable_pages == 0)
455 for (i = 0; i < rte_socket_count(); i++) {
456 int socket = rte_socket_id_by_idx(i);
457 unsigned int num_pages =
458 get_num_hugepages_on_node(
459 dirent->d_name, socket,
460 hpi->hugepage_sz);
461 hpi->num_pages[socket] = num_pages;
462 total_pages += num_pages;
463 }
464 /*
465 * we failed to sort memory from the get go, so fall
466 * back to old way
467 */
468 if (total_pages == 0) {
469 hpi->num_pages[0] = get_num_hugepages(dirent->d_name,
470 hpi->hugepage_sz, reusable_pages);
471
472 #ifndef RTE_ARCH_64
473 /* for 32-bit systems, limit number of hugepages to
474 * 1GB per page size */
475 hpi->num_pages[0] = RTE_MIN(hpi->num_pages[0],
476 RTE_PGSIZE_1G / hpi->hugepage_sz);
477 #endif
478 }
479 }
480
481 static int
hugepage_info_init(void)482 hugepage_info_init(void)
483 { const char dirent_start_text[] = "hugepages-";
484 const size_t dirent_start_len = sizeof(dirent_start_text) - 1;
485 unsigned int i, num_sizes = 0;
486 uint64_t reusable_bytes;
487 unsigned int reusable_pages;
488 DIR *dir;
489 struct dirent *dirent;
490 struct internal_config *internal_conf =
491 eal_get_internal_configuration();
492
493 dir = opendir(sys_dir_path);
494 if (dir == NULL) {
495 EAL_LOG(ERR,
496 "Cannot open directory %s to read system hugepage info",
497 sys_dir_path);
498 return -1;
499 }
500
501 for (dirent = readdir(dir); dirent != NULL; dirent = readdir(dir)) {
502 struct hugepage_info *hpi;
503
504 if (strncmp(dirent->d_name, dirent_start_text,
505 dirent_start_len) != 0)
506 continue;
507
508 if (num_sizes >= MAX_HUGEPAGE_SIZES)
509 break;
510
511 hpi = &internal_conf->hugepage_info[num_sizes];
512 hpi->hugepage_sz =
513 rte_str_to_size(&dirent->d_name[dirent_start_len]);
514
515 /* first, check if we have a mountpoint */
516 if (get_hugepage_dir(hpi->hugepage_sz,
517 hpi->hugedir, sizeof(hpi->hugedir)) < 0) {
518 uint32_t num_pages;
519
520 num_pages = get_num_hugepages(dirent->d_name,
521 hpi->hugepage_sz, 0);
522 if (num_pages > 0)
523 EAL_LOG(NOTICE,
524 "%" PRIu32 " hugepages of size "
525 "%" PRIu64 " reserved, but no mounted "
526 "hugetlbfs found for that size",
527 num_pages, hpi->hugepage_sz);
528 /* if we have kernel support for reserving hugepages
529 * through mmap, and we're in in-memory mode, treat this
530 * page size as valid. we cannot be in legacy mode at
531 * this point because we've checked this earlier in the
532 * init process.
533 */
534 #ifdef MAP_HUGE_SHIFT
535 if (internal_conf->in_memory) {
536 EAL_LOG(DEBUG, "In-memory mode enabled, "
537 "hugepages of size %" PRIu64 " bytes "
538 "will be allocated anonymously",
539 hpi->hugepage_sz);
540 calc_num_pages(hpi, dirent, 0);
541 num_sizes++;
542 }
543 #endif
544 continue;
545 }
546
547 /* try to obtain a writelock */
548 hpi->lock_descriptor = open(hpi->hugedir, O_RDONLY);
549
550 /* if blocking lock failed */
551 if (flock(hpi->lock_descriptor, LOCK_EX) == -1) {
552 EAL_LOG(CRIT,
553 "Failed to lock hugepage directory!");
554 break;
555 }
556
557 /*
558 * Check for existing hugepage files and either remove them
559 * or count how many of them can be reused.
560 */
561 reusable_pages = 0;
562 if (!internal_conf->hugepage_file.unlink_existing) {
563 reusable_bytes = 0;
564 if (inspect_hugedir(hpi->hugedir,
565 &reusable_bytes) < 0)
566 break;
567 RTE_ASSERT(reusable_bytes % hpi->hugepage_sz == 0);
568 reusable_pages = reusable_bytes / hpi->hugepage_sz;
569 } else if (clear_hugedir(hpi->hugedir) < 0) {
570 break;
571 }
572 calc_num_pages(hpi, dirent, reusable_pages);
573
574 num_sizes++;
575 }
576 closedir(dir);
577
578 /* something went wrong, and we broke from the for loop above */
579 if (dirent != NULL)
580 return -1;
581
582 internal_conf->num_hugepage_sizes = num_sizes;
583
584 /* sort the page directory entries by size, largest to smallest */
585 qsort(&internal_conf->hugepage_info[0], num_sizes,
586 sizeof(internal_conf->hugepage_info[0]), compare_hpi);
587
588 /* now we have all info, check we have at least one valid size */
589 for (i = 0; i < num_sizes; i++) {
590 /* pages may no longer all be on socket 0, so check all */
591 unsigned int j, num_pages = 0;
592 struct hugepage_info *hpi = &internal_conf->hugepage_info[i];
593
594 for (j = 0; j < RTE_MAX_NUMA_NODES; j++)
595 num_pages += hpi->num_pages[j];
596 if (num_pages > 0)
597 return 0;
598 }
599
600 /* no valid hugepage mounts available, return error */
601 return -1;
602 }
603
604 /*
605 * when we initialize the hugepage info, everything goes
606 * to socket 0 by default. it will later get sorted by memory
607 * initialization procedure.
608 */
609 int
eal_hugepage_info_init(void)610 eal_hugepage_info_init(void)
611 {
612 struct hugepage_info *hpi, *tmp_hpi;
613 unsigned int i;
614 struct internal_config *internal_conf =
615 eal_get_internal_configuration();
616
617 if (hugepage_info_init() < 0)
618 return -1;
619
620 /* for no shared files mode, we're done */
621 if (internal_conf->no_shconf)
622 return 0;
623
624 hpi = &internal_conf->hugepage_info[0];
625
626 tmp_hpi = create_shared_memory(eal_hugepage_info_path(),
627 sizeof(internal_conf->hugepage_info));
628 if (tmp_hpi == NULL) {
629 EAL_LOG(ERR, "Failed to create shared memory!");
630 return -1;
631 }
632
633 memcpy(tmp_hpi, hpi, sizeof(internal_conf->hugepage_info));
634
635 /* we've copied file descriptors along with everything else, but they
636 * will be invalid in secondary process, so overwrite them
637 */
638 for (i = 0; i < RTE_DIM(internal_conf->hugepage_info); i++) {
639 struct hugepage_info *tmp = &tmp_hpi[i];
640 tmp->lock_descriptor = -1;
641 }
642
643 if (munmap(tmp_hpi, sizeof(internal_conf->hugepage_info)) < 0) {
644 EAL_LOG(ERR, "Failed to unmap shared memory!");
645 return -1;
646 }
647 return 0;
648 }
649
eal_hugepage_info_read(void)650 int eal_hugepage_info_read(void)
651 {
652 struct internal_config *internal_conf =
653 eal_get_internal_configuration();
654 struct hugepage_info *hpi = &internal_conf->hugepage_info[0];
655 struct hugepage_info *tmp_hpi;
656
657 tmp_hpi = open_shared_memory(eal_hugepage_info_path(),
658 sizeof(internal_conf->hugepage_info));
659 if (tmp_hpi == NULL) {
660 EAL_LOG(ERR, "Failed to open shared memory!");
661 return -1;
662 }
663
664 memcpy(hpi, tmp_hpi, sizeof(internal_conf->hugepage_info));
665
666 if (munmap(tmp_hpi, sizeof(internal_conf->hugepage_info)) < 0) {
667 EAL_LOG(ERR, "Failed to unmap shared memory!");
668 return -1;
669 }
670 return 0;
671 }
672