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;
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 RTE_LOG(WARNING, EAL, "No available %zu kB hugepages reported\n",
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 RTE_LOG(WARNING, EAL, "No free %zu kB hugepages reported on node %u\n",
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 struct stat st;
218
219 /*
220 * If the specified dir doesn't exist, we can't match it.
221 */
222 if (internal_conf->hugepage_dir != NULL &&
223 stat(internal_conf->hugepage_dir, &st) != 0) {
224 return -1;
225 }
226
227 FILE *fd = fopen(proc_mounts, "r");
228 if (fd == NULL)
229 rte_panic("Cannot open %s\n", proc_mounts);
230
231 if (default_size == 0)
232 default_size = get_default_hp_size();
233
234 while (fgets(buf, sizeof(buf), fd)){
235 const char *pagesz_str;
236
237 if (rte_strsplit(buf, sizeof(buf), splitstr, _FIELDNAME_MAX,
238 split_tok) != _FIELDNAME_MAX) {
239 RTE_LOG(ERR, EAL, "Error parsing %s\n", proc_mounts);
240 break; /* return NULL */
241 }
242
243 if (strncmp(splitstr[FSTYPE], hugetlbfs_str, htlbfs_str_len) != 0)
244 continue;
245
246 pagesz_str = strstr(splitstr[OPTIONS], pagesize_opt);
247
248 /* if no explicit page size, the default page size is compared */
249 if (pagesz_str == NULL) {
250 if (hugepage_sz != default_size)
251 continue;
252 }
253 /* there is an explicit page size, so check it */
254 else {
255 uint64_t pagesz = rte_str_to_size(&pagesz_str[pagesize_opt_len]);
256 if (pagesz != hugepage_sz)
257 continue;
258 }
259
260 /*
261 * If no --huge-dir option has been given, we're done.
262 */
263 if (internal_conf->hugepage_dir == NULL) {
264 strlcpy(found, splitstr[MOUNTPT], len);
265 break;
266 }
267
268 /*
269 * Ignore any mount that doesn't contain the --huge-dir
270 * directory.
271 */
272 if (strncmp(internal_conf->hugepage_dir, splitstr[MOUNTPT],
273 strlen(splitstr[MOUNTPT])) != 0) {
274 continue;
275 }
276
277 /*
278 * We found a match, but only prefer it if it's a longer match
279 * (so /mnt/1 is preferred over /mnt for matching /mnt/1/2)).
280 */
281 if (strlen(splitstr[MOUNTPT]) > strlen(found))
282 strlcpy(found, splitstr[MOUNTPT], len);
283 } /* end while fgets */
284
285 fclose(fd);
286
287 if (found[0] != '\0') {
288 /* If needed, return the requested dir, not the mount point. */
289 strlcpy(hugedir, internal_conf->hugepage_dir != NULL ?
290 internal_conf->hugepage_dir : found, len);
291 return 0;
292 }
293
294 return -1;
295 }
296
297 struct walk_hugedir_data {
298 int dir_fd;
299 int file_fd;
300 const char *file_name;
301 void *user_data;
302 };
303
304 typedef void (walk_hugedir_t)(const struct walk_hugedir_data *whd);
305
306 /*
307 * Search the hugepage directory for whatever hugepage files there are.
308 * Check if the file is in use by another DPDK process.
309 * If not, execute a callback on it.
310 */
311 static int
walk_hugedir(const char * hugedir,walk_hugedir_t * cb,void * user_data)312 walk_hugedir(const char *hugedir, walk_hugedir_t *cb, void *user_data)
313 {
314 DIR *dir;
315 struct dirent *dirent;
316 int dir_fd, fd, lck_result;
317 const char filter[] = "*map_*"; /* matches hugepage files */
318
319 dir = opendir(hugedir);
320 if (!dir) {
321 RTE_LOG(ERR, EAL, "Unable to open hugepage directory %s\n",
322 hugedir);
323 goto error;
324 }
325 dir_fd = dirfd(dir);
326
327 dirent = readdir(dir);
328 if (!dirent) {
329 RTE_LOG(ERR, EAL, "Unable to read hugepage directory %s\n",
330 hugedir);
331 goto error;
332 }
333
334 while (dirent != NULL) {
335 /* skip files that don't match the hugepage pattern */
336 if (fnmatch(filter, dirent->d_name, 0) > 0) {
337 dirent = readdir(dir);
338 continue;
339 }
340
341 /* try and lock the file */
342 fd = openat(dir_fd, dirent->d_name, O_RDONLY);
343
344 /* skip to next file */
345 if (fd == -1) {
346 dirent = readdir(dir);
347 continue;
348 }
349
350 /* non-blocking lock */
351 lck_result = flock(fd, LOCK_EX | LOCK_NB);
352
353 /* if lock succeeds, execute callback */
354 if (lck_result != -1)
355 cb(&(struct walk_hugedir_data){
356 .dir_fd = dir_fd,
357 .file_fd = fd,
358 .file_name = dirent->d_name,
359 .user_data = user_data,
360 });
361
362 close (fd);
363 dirent = readdir(dir);
364 }
365
366 closedir(dir);
367 return 0;
368
369 error:
370 if (dir)
371 closedir(dir);
372
373 RTE_LOG(ERR, EAL, "Error while walking hugepage dir: %s\n",
374 strerror(errno));
375
376 return -1;
377 }
378
379 static void
clear_hugedir_cb(const struct walk_hugedir_data * whd)380 clear_hugedir_cb(const struct walk_hugedir_data *whd)
381 {
382 unlinkat(whd->dir_fd, whd->file_name, 0);
383 }
384
385 /* Remove hugepage files not used by other DPDK processes from a directory. */
386 static int
clear_hugedir(const char * hugedir)387 clear_hugedir(const char *hugedir)
388 {
389 return walk_hugedir(hugedir, clear_hugedir_cb, NULL);
390 }
391
392 static void
inspect_hugedir_cb(const struct walk_hugedir_data * whd)393 inspect_hugedir_cb(const struct walk_hugedir_data *whd)
394 {
395 uint64_t *total_size = whd->user_data;
396 struct stat st;
397
398 if (fstat(whd->file_fd, &st) < 0)
399 RTE_LOG(DEBUG, EAL, "%s(): stat(\"%s\") failed: %s",
400 __func__, whd->file_name, strerror(errno));
401 else
402 (*total_size) += st.st_size;
403 }
404
405 /*
406 * Count the total size in bytes of all files in the directory
407 * not mapped by other DPDK process.
408 */
409 static int
inspect_hugedir(const char * hugedir,uint64_t * total_size)410 inspect_hugedir(const char *hugedir, uint64_t *total_size)
411 {
412 return walk_hugedir(hugedir, inspect_hugedir_cb, total_size);
413 }
414
415 static int
compare_hpi(const void * a,const void * b)416 compare_hpi(const void *a, const void *b)
417 {
418 const struct hugepage_info *hpi_a = a;
419 const struct hugepage_info *hpi_b = b;
420
421 return hpi_b->hugepage_sz - hpi_a->hugepage_sz;
422 }
423
424 static void
calc_num_pages(struct hugepage_info * hpi,struct dirent * dirent,unsigned int reusable_pages)425 calc_num_pages(struct hugepage_info *hpi, struct dirent *dirent,
426 unsigned int reusable_pages)
427 {
428 uint64_t total_pages = 0;
429 unsigned int i;
430 const struct internal_config *internal_conf =
431 eal_get_internal_configuration();
432
433 /*
434 * first, try to put all hugepages into relevant sockets, but
435 * if first attempts fails, fall back to collecting all pages
436 * in one socket and sorting them later
437 */
438 total_pages = 0;
439
440 /*
441 * We also don't want to do this for legacy init.
442 * When there are hugepage files to reuse it is unknown
443 * what NUMA node the pages are on.
444 * This could be determined by mapping,
445 * but it is precisely what hugepage file reuse is trying to avoid.
446 */
447 if (!internal_conf->legacy_mem && reusable_pages == 0)
448 for (i = 0; i < rte_socket_count(); i++) {
449 int socket = rte_socket_id_by_idx(i);
450 unsigned int num_pages =
451 get_num_hugepages_on_node(
452 dirent->d_name, socket,
453 hpi->hugepage_sz);
454 hpi->num_pages[socket] = num_pages;
455 total_pages += num_pages;
456 }
457 /*
458 * we failed to sort memory from the get go, so fall
459 * back to old way
460 */
461 if (total_pages == 0) {
462 hpi->num_pages[0] = get_num_hugepages(dirent->d_name,
463 hpi->hugepage_sz, reusable_pages);
464
465 #ifndef RTE_ARCH_64
466 /* for 32-bit systems, limit number of hugepages to
467 * 1GB per page size */
468 hpi->num_pages[0] = RTE_MIN(hpi->num_pages[0],
469 RTE_PGSIZE_1G / hpi->hugepage_sz);
470 #endif
471 }
472 }
473
474 static int
hugepage_info_init(void)475 hugepage_info_init(void)
476 { const char dirent_start_text[] = "hugepages-";
477 const size_t dirent_start_len = sizeof(dirent_start_text) - 1;
478 unsigned int i, num_sizes = 0;
479 uint64_t reusable_bytes;
480 unsigned int reusable_pages;
481 DIR *dir;
482 struct dirent *dirent;
483 struct internal_config *internal_conf =
484 eal_get_internal_configuration();
485
486 dir = opendir(sys_dir_path);
487 if (dir == NULL) {
488 RTE_LOG(ERR, EAL,
489 "Cannot open directory %s to read system hugepage info\n",
490 sys_dir_path);
491 return -1;
492 }
493
494 for (dirent = readdir(dir); dirent != NULL; dirent = readdir(dir)) {
495 struct hugepage_info *hpi;
496
497 if (strncmp(dirent->d_name, dirent_start_text,
498 dirent_start_len) != 0)
499 continue;
500
501 if (num_sizes >= MAX_HUGEPAGE_SIZES)
502 break;
503
504 hpi = &internal_conf->hugepage_info[num_sizes];
505 hpi->hugepage_sz =
506 rte_str_to_size(&dirent->d_name[dirent_start_len]);
507
508 /* first, check if we have a mountpoint */
509 if (get_hugepage_dir(hpi->hugepage_sz,
510 hpi->hugedir, sizeof(hpi->hugedir)) < 0) {
511 uint32_t num_pages;
512
513 num_pages = get_num_hugepages(dirent->d_name,
514 hpi->hugepage_sz, 0);
515 if (num_pages > 0)
516 RTE_LOG(NOTICE, EAL,
517 "%" PRIu32 " hugepages of size "
518 "%" PRIu64 " reserved, but no mounted "
519 "hugetlbfs found for that size\n",
520 num_pages, hpi->hugepage_sz);
521 /* if we have kernel support for reserving hugepages
522 * through mmap, and we're in in-memory mode, treat this
523 * page size as valid. we cannot be in legacy mode at
524 * this point because we've checked this earlier in the
525 * init process.
526 */
527 #ifdef MAP_HUGE_SHIFT
528 if (internal_conf->in_memory) {
529 RTE_LOG(DEBUG, EAL, "In-memory mode enabled, "
530 "hugepages of size %" PRIu64 " bytes "
531 "will be allocated anonymously\n",
532 hpi->hugepage_sz);
533 calc_num_pages(hpi, dirent, 0);
534 num_sizes++;
535 }
536 #endif
537 continue;
538 }
539
540 /* try to obtain a writelock */
541 hpi->lock_descriptor = open(hpi->hugedir, O_RDONLY);
542
543 /* if blocking lock failed */
544 if (flock(hpi->lock_descriptor, LOCK_EX) == -1) {
545 RTE_LOG(CRIT, EAL,
546 "Failed to lock hugepage directory!\n");
547 break;
548 }
549
550 /*
551 * Check for existing hugepage files and either remove them
552 * or count how many of them can be reused.
553 */
554 reusable_pages = 0;
555 if (!internal_conf->hugepage_file.unlink_existing) {
556 reusable_bytes = 0;
557 if (inspect_hugedir(hpi->hugedir,
558 &reusable_bytes) < 0)
559 break;
560 RTE_ASSERT(reusable_bytes % hpi->hugepage_sz == 0);
561 reusable_pages = reusable_bytes / hpi->hugepage_sz;
562 } else if (clear_hugedir(hpi->hugedir) < 0) {
563 break;
564 }
565 calc_num_pages(hpi, dirent, reusable_pages);
566
567 num_sizes++;
568 }
569 closedir(dir);
570
571 /* something went wrong, and we broke from the for loop above */
572 if (dirent != NULL)
573 return -1;
574
575 internal_conf->num_hugepage_sizes = num_sizes;
576
577 /* sort the page directory entries by size, largest to smallest */
578 qsort(&internal_conf->hugepage_info[0], num_sizes,
579 sizeof(internal_conf->hugepage_info[0]), compare_hpi);
580
581 /* now we have all info, check we have at least one valid size */
582 for (i = 0; i < num_sizes; i++) {
583 /* pages may no longer all be on socket 0, so check all */
584 unsigned int j, num_pages = 0;
585 struct hugepage_info *hpi = &internal_conf->hugepage_info[i];
586
587 for (j = 0; j < RTE_MAX_NUMA_NODES; j++)
588 num_pages += hpi->num_pages[j];
589 if (num_pages > 0)
590 return 0;
591 }
592
593 /* no valid hugepage mounts available, return error */
594 return -1;
595 }
596
597 /*
598 * when we initialize the hugepage info, everything goes
599 * to socket 0 by default. it will later get sorted by memory
600 * initialization procedure.
601 */
602 int
eal_hugepage_info_init(void)603 eal_hugepage_info_init(void)
604 {
605 struct hugepage_info *hpi, *tmp_hpi;
606 unsigned int i;
607 struct internal_config *internal_conf =
608 eal_get_internal_configuration();
609
610 if (hugepage_info_init() < 0)
611 return -1;
612
613 /* for no shared files mode, we're done */
614 if (internal_conf->no_shconf)
615 return 0;
616
617 hpi = &internal_conf->hugepage_info[0];
618
619 tmp_hpi = create_shared_memory(eal_hugepage_info_path(),
620 sizeof(internal_conf->hugepage_info));
621 if (tmp_hpi == NULL) {
622 RTE_LOG(ERR, EAL, "Failed to create shared memory!\n");
623 return -1;
624 }
625
626 memcpy(tmp_hpi, hpi, sizeof(internal_conf->hugepage_info));
627
628 /* we've copied file descriptors along with everything else, but they
629 * will be invalid in secondary process, so overwrite them
630 */
631 for (i = 0; i < RTE_DIM(internal_conf->hugepage_info); i++) {
632 struct hugepage_info *tmp = &tmp_hpi[i];
633 tmp->lock_descriptor = -1;
634 }
635
636 if (munmap(tmp_hpi, sizeof(internal_conf->hugepage_info)) < 0) {
637 RTE_LOG(ERR, EAL, "Failed to unmap shared memory!\n");
638 return -1;
639 }
640 return 0;
641 }
642
eal_hugepage_info_read(void)643 int eal_hugepage_info_read(void)
644 {
645 struct internal_config *internal_conf =
646 eal_get_internal_configuration();
647 struct hugepage_info *hpi = &internal_conf->hugepage_info[0];
648 struct hugepage_info *tmp_hpi;
649
650 tmp_hpi = open_shared_memory(eal_hugepage_info_path(),
651 sizeof(internal_conf->hugepage_info));
652 if (tmp_hpi == NULL) {
653 RTE_LOG(ERR, EAL, "Failed to open shared memory!\n");
654 return -1;
655 }
656
657 memcpy(hpi, tmp_hpi, sizeof(internal_conf->hugepage_info));
658
659 if (munmap(tmp_hpi, sizeof(internal_conf->hugepage_info)) < 0) {
660 RTE_LOG(ERR, EAL, "Failed to unmap shared memory!\n");
661 return -1;
662 }
663 return 0;
664 }
665