1 /* SPDX-License-Identifier: BSD-3-Clause
2 * Copyright(c) 2010-2014 Intel Corporation
19 #include <linux/mman.h> /* for hugetlb-related flags */
21 #include <rte_lcore.h>
22 #include <rte_debug.h>
24 #include <rte_common.h>
25 #include "rte_string_fns.h"
27 #include "eal_private.h"
28 #include "eal_internal_cfg.h"
29 #include "eal_hugepages.h"
30 #include "eal_filesystem.h"
32 static const char sys_dir_path[] = "/sys/kernel/mm/hugepages";
33 static const char sys_pages_numa_dir_path[] = "/sys/devices/system/node";
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
40 map_shared_memory(const char *filename, const size_t mem_size, int flags)
43 int fd = open(filename, flags, 0600);
46 if (ftruncate(fd, mem_size) < 0) {
50 retval = mmap(NULL, mem_size, PROT_READ | PROT_WRITE,
57 open_shared_memory(const char *filename, const size_t mem_size)
59 return map_shared_memory(filename, mem_size, O_RDWR);
63 create_shared_memory(const char *filename, const size_t mem_size)
65 return map_shared_memory(filename, mem_size, O_RDWR | O_CREAT);
68 static int get_hp_sysfs_value(const char *subdir, const char *file, unsigned long *val)
72 snprintf(path, sizeof(path), "%s/%s/%s",
73 sys_dir_path, subdir, file);
74 return eal_parse_sysfs_value(path, val);
77 /* this function is only called from eal_hugepage_info_init which itself
78 * is only called from a primary process */
80 get_num_hugepages(const char *subdir, size_t sz, unsigned int reusable_pages)
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";
88 /* first, check how many reserved pages kernel reports */
89 if (get_hp_sysfs_value(subdir, nr_rsvd_file, &resv_pages) < 0)
92 if (get_hp_sysfs_value(subdir, nr_hp_file, &num_pages) < 0)
95 if (get_hp_sysfs_value(subdir, nr_over_file, &over_pages) < 0)
98 if (get_hp_sysfs_value(subdir, nr_splus_file, &surplus_pages) < 0)
101 /* adjust num_pages */
102 if (num_pages >= resv_pages)
103 num_pages -= resv_pages;
107 if (over_pages >= surplus_pages)
108 over_pages -= surplus_pages;
112 if (num_pages == 0 && over_pages == 0 && reusable_pages)
113 RTE_LOG(WARNING, EAL, "No available %zu kB hugepages reported\n",
116 num_pages += over_pages;
117 if (num_pages < over_pages) /* overflow */
118 num_pages = UINT32_MAX;
120 num_pages += reusable_pages;
121 if (num_pages < reusable_pages) /* overflow */
122 num_pages = UINT32_MAX;
124 /* we want to return a uint32_t and more than this looks suspicious
126 if (num_pages > UINT32_MAX)
127 num_pages = UINT32_MAX;
133 get_num_hugepages_on_node(const char *subdir, unsigned int socket, size_t sz)
135 char path[PATH_MAX], socketpath[PATH_MAX];
137 unsigned long num_pages = 0;
138 const char *nr_hp_file = "free_hugepages";
140 snprintf(socketpath, sizeof(socketpath), "%s/node%u/hugepages",
141 sys_pages_numa_dir_path, socket);
143 socketdir = opendir(socketpath);
145 /* Keep calm and carry on */
148 /* Can't find socket dir, so ignore it */
152 snprintf(path, sizeof(path), "%s/%s/%s",
153 socketpath, subdir, nr_hp_file);
154 if (eal_parse_sysfs_value(path, &num_pages) < 0)
158 RTE_LOG(WARNING, EAL, "No free %zu kB hugepages reported on node %u\n",
162 * we want to return a uint32_t and more than this looks suspicious
165 if (num_pages > UINT32_MAX)
166 num_pages = UINT32_MAX;
172 get_default_hp_size(void)
174 const char proc_meminfo[] = "/proc/meminfo";
175 const char str_hugepagesz[] = "Hugepagesize:";
176 unsigned hugepagesz_len = sizeof(str_hugepagesz) - 1;
178 unsigned long long size = 0;
180 FILE *fd = fopen(proc_meminfo, "r");
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]);
191 rte_panic("Cannot get default hugepage size from %s\n", proc_meminfo);
196 get_hugepage_dir(uint64_t hugepage_sz, char *hugedir, int len)
198 enum proc_mount_fieldnames {
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] = "";
215 const struct internal_config *internal_conf =
216 eal_get_internal_configuration();
220 * If the specified dir doesn't exist, we can't match it.
222 if (internal_conf->hugepage_dir != NULL &&
223 stat(internal_conf->hugepage_dir, &st) != 0) {
227 FILE *fd = fopen(proc_mounts, "r");
229 rte_panic("Cannot open %s\n", proc_mounts);
231 if (default_size == 0)
232 default_size = get_default_hp_size();
234 while (fgets(buf, sizeof(buf), fd)){
235 const char *pagesz_str;
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 */
243 if (strncmp(splitstr[FSTYPE], hugetlbfs_str, htlbfs_str_len) != 0)
246 pagesz_str = strstr(splitstr[OPTIONS], pagesize_opt);
248 /* if no explicit page size, the default page size is compared */
249 if (pagesz_str == NULL) {
250 if (hugepage_sz != default_size)
253 /* there is an explicit page size, so check it */
255 uint64_t pagesz = rte_str_to_size(&pagesz_str[pagesize_opt_len]);
256 if (pagesz != hugepage_sz)
261 * If no --huge-dir option has been given, we're done.
263 if (internal_conf->hugepage_dir == NULL) {
264 strlcpy(found, splitstr[MOUNTPT], len);
269 * Ignore any mount that doesn't contain the --huge-dir
272 if (strncmp(internal_conf->hugepage_dir, splitstr[MOUNTPT],
273 strlen(splitstr[MOUNTPT])) != 0) {
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)).
281 if (strlen(splitstr[MOUNTPT]) > strlen(found))
282 strlcpy(found, splitstr[MOUNTPT], len);
283 } /* end while fgets */
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);
297 struct walk_hugedir_data {
300 const char *file_name;
304 typedef void (walk_hugedir_t)(const struct walk_hugedir_data *whd);
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.
312 walk_hugedir(const char *hugedir, walk_hugedir_t *cb, void *user_data)
315 struct dirent *dirent;
316 int dir_fd, fd, lck_result;
317 const char filter[] = "*map_*"; /* matches hugepage files */
319 dir = opendir(hugedir);
321 RTE_LOG(ERR, EAL, "Unable to open hugepage directory %s\n",
327 dirent = readdir(dir);
329 RTE_LOG(ERR, EAL, "Unable to read hugepage directory %s\n",
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);
341 /* try and lock the file */
342 fd = openat(dir_fd, dirent->d_name, O_RDONLY);
344 /* skip to next file */
346 dirent = readdir(dir);
350 /* non-blocking lock */
351 lck_result = flock(fd, LOCK_EX | LOCK_NB);
353 /* if lock succeeds, execute callback */
354 if (lck_result != -1)
355 cb(&(struct walk_hugedir_data){
358 .file_name = dirent->d_name,
359 .user_data = user_data,
363 dirent = readdir(dir);
373 RTE_LOG(ERR, EAL, "Error while walking hugepage dir: %s\n",
380 clear_hugedir_cb(const struct walk_hugedir_data *whd)
382 unlinkat(whd->dir_fd, whd->file_name, 0);
385 /* Remove hugepage files not used by other DPDK processes from a directory. */
387 clear_hugedir(const char *hugedir)
389 return walk_hugedir(hugedir, clear_hugedir_cb, NULL);
393 inspect_hugedir_cb(const struct walk_hugedir_data *whd)
395 uint64_t *total_size = whd->user_data;
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));
402 (*total_size) += st.st_size;
406 * Count the total size in bytes of all files in the directory
407 * not mapped by other DPDK process.
410 inspect_hugedir(const char *hugedir, uint64_t *total_size)
412 return walk_hugedir(hugedir, inspect_hugedir_cb, total_size);
416 compare_hpi(const void *a, const void *b)
418 const struct hugepage_info *hpi_a = a;
419 const struct hugepage_info *hpi_b = b;
421 return hpi_b->hugepage_sz - hpi_a->hugepage_sz;
425 calc_num_pages(struct hugepage_info *hpi, struct dirent *dirent,
426 unsigned int reusable_pages)
428 uint64_t total_pages = 0;
430 const struct internal_config *internal_conf =
431 eal_get_internal_configuration();
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
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.
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,
454 hpi->num_pages[socket] = num_pages;
455 total_pages += num_pages;
458 * we failed to sort memory from the get go, so fall
461 if (total_pages == 0) {
462 hpi->num_pages[0] = get_num_hugepages(dirent->d_name,
463 hpi->hugepage_sz, reusable_pages);
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);
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;
482 struct dirent *dirent;
483 struct internal_config *internal_conf =
484 eal_get_internal_configuration();
486 dir = opendir(sys_dir_path);
489 "Cannot open directory %s to read system hugepage info\n",
494 for (dirent = readdir(dir); dirent != NULL; dirent = readdir(dir)) {
495 struct hugepage_info *hpi;
497 if (strncmp(dirent->d_name, dirent_start_text,
498 dirent_start_len) != 0)
501 if (num_sizes >= MAX_HUGEPAGE_SIZES)
504 hpi = &internal_conf->hugepage_info[num_sizes];
506 rte_str_to_size(&dirent->d_name[dirent_start_len]);
508 /* first, check if we have a mountpoint */
509 if (get_hugepage_dir(hpi->hugepage_sz,
510 hpi->hugedir, sizeof(hpi->hugedir)) < 0) {
513 num_pages = get_num_hugepages(dirent->d_name,
514 hpi->hugepage_sz, 0);
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
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",
533 calc_num_pages(hpi, dirent, 0);
540 /* try to obtain a writelock */
541 hpi->lock_descriptor = open(hpi->hugedir, O_RDONLY);
543 /* if blocking lock failed */
544 if (flock(hpi->lock_descriptor, LOCK_EX) == -1) {
546 "Failed to lock hugepage directory!\n");
551 * Check for existing hugepage files and either remove them
552 * or count how many of them can be reused.
555 if (!internal_conf->hugepage_file.unlink_existing) {
557 if (inspect_hugedir(hpi->hugedir,
558 &reusable_bytes) < 0)
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) {
565 calc_num_pages(hpi, dirent, reusable_pages);
571 /* something went wrong, and we broke from the for loop above */
575 internal_conf->num_hugepage_sizes = num_sizes;
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);
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];
587 for (j = 0; j < RTE_MAX_NUMA_NODES; j++)
588 num_pages += hpi->num_pages[j];
593 /* no valid hugepage mounts available, return error */
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.
603 eal_hugepage_info_init(void)
605 struct hugepage_info *hpi, *tmp_hpi;
607 struct internal_config *internal_conf =
608 eal_get_internal_configuration();
610 if (hugepage_info_init() < 0)
613 /* for no shared files mode, we're done */
614 if (internal_conf->no_shconf)
617 hpi = &internal_conf->hugepage_info[0];
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");
626 memcpy(tmp_hpi, hpi, sizeof(internal_conf->hugepage_info));
628 /* we've copied file descriptors along with everything else, but they
629 * will be invalid in secondary process, so overwrite them
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;
636 if (munmap(tmp_hpi, sizeof(internal_conf->hugepage_info)) < 0) {
637 RTE_LOG(ERR, EAL, "Failed to unmap shared memory!\n");
643 int eal_hugepage_info_read(void)
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;
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");
657 memcpy(hpi, tmp_hpi, sizeof(internal_conf->hugepage_info));
659 if (munmap(tmp_hpi, sizeof(internal_conf->hugepage_info)) < 0) {
660 RTE_LOG(ERR, EAL, "Failed to unmap shared memory!\n");