1 /* SPDX-License-Identifier: BSD-3-Clause
2 * Copyright(c) 2010-2014 Intel Corporation
19 #include <sys/queue.h>
22 #include <linux/mman.h> /* for hugetlb-related flags */
24 #include <rte_memory.h>
26 #include <rte_launch.h>
27 #include <rte_per_lcore.h>
28 #include <rte_lcore.h>
29 #include <rte_debug.h>
31 #include <rte_common.h>
32 #include "rte_string_fns.h"
33 #include "eal_internal_cfg.h"
34 #include "eal_hugepages.h"
35 #include "eal_filesystem.h"
37 static const char sys_dir_path[] = "/sys/kernel/mm/hugepages";
38 static const char sys_pages_numa_dir_path[] = "/sys/devices/system/node";
41 * Uses mmap to create a shared memory area for storage of data
42 * Used in this file to store the hugepage file map on disk
45 map_shared_memory(const char *filename, const size_t mem_size, int flags)
48 int fd = open(filename, flags, 0666);
51 if (ftruncate(fd, mem_size) < 0) {
55 retval = mmap(NULL, mem_size, PROT_READ | PROT_WRITE,
62 open_shared_memory(const char *filename, const size_t mem_size)
64 return map_shared_memory(filename, mem_size, O_RDWR);
68 create_shared_memory(const char *filename, const size_t mem_size)
70 return map_shared_memory(filename, mem_size, O_RDWR | O_CREAT);
73 /* this function is only called from eal_hugepage_info_init which itself
74 * is only called from a primary process */
76 get_num_hugepages(const char *subdir)
79 long unsigned resv_pages, num_pages = 0;
80 const char *nr_hp_file = "free_hugepages";
81 const char *nr_rsvd_file = "resv_hugepages";
83 /* first, check how many reserved pages kernel reports */
84 snprintf(path, sizeof(path), "%s/%s/%s",
85 sys_dir_path, subdir, nr_rsvd_file);
86 if (eal_parse_sysfs_value(path, &resv_pages) < 0)
89 snprintf(path, sizeof(path), "%s/%s/%s",
90 sys_dir_path, subdir, nr_hp_file);
91 if (eal_parse_sysfs_value(path, &num_pages) < 0)
95 RTE_LOG(WARNING, EAL, "No free hugepages reported in %s\n",
98 /* adjust num_pages */
99 if (num_pages >= resv_pages)
100 num_pages -= resv_pages;
104 /* we want to return a uint32_t and more than this looks suspicious
106 if (num_pages > UINT32_MAX)
107 num_pages = UINT32_MAX;
113 get_num_hugepages_on_node(const char *subdir, unsigned int socket)
115 char path[PATH_MAX], socketpath[PATH_MAX];
117 unsigned long num_pages = 0;
118 const char *nr_hp_file = "free_hugepages";
120 snprintf(socketpath, sizeof(socketpath), "%s/node%u/hugepages",
121 sys_pages_numa_dir_path, socket);
123 socketdir = opendir(socketpath);
125 /* Keep calm and carry on */
128 /* Can't find socket dir, so ignore it */
132 snprintf(path, sizeof(path), "%s/%s/%s",
133 socketpath, subdir, nr_hp_file);
134 if (eal_parse_sysfs_value(path, &num_pages) < 0)
138 RTE_LOG(WARNING, EAL, "No free hugepages reported in %s\n",
142 * we want to return a uint32_t and more than this looks suspicious
145 if (num_pages > UINT32_MAX)
146 num_pages = UINT32_MAX;
152 get_default_hp_size(void)
154 const char proc_meminfo[] = "/proc/meminfo";
155 const char str_hugepagesz[] = "Hugepagesize:";
156 unsigned hugepagesz_len = sizeof(str_hugepagesz) - 1;
158 unsigned long long size = 0;
160 FILE *fd = fopen(proc_meminfo, "r");
162 rte_panic("Cannot open %s\n", proc_meminfo);
163 while(fgets(buffer, sizeof(buffer), fd)){
164 if (strncmp(buffer, str_hugepagesz, hugepagesz_len) == 0){
165 size = rte_str_to_size(&buffer[hugepagesz_len]);
171 rte_panic("Cannot get default hugepage size from %s\n", proc_meminfo);
176 get_hugepage_dir(uint64_t hugepage_sz, char *hugedir, int len)
178 enum proc_mount_fieldnames {
185 static uint64_t default_size = 0;
186 const char proc_mounts[] = "/proc/mounts";
187 const char hugetlbfs_str[] = "hugetlbfs";
188 const size_t htlbfs_str_len = sizeof(hugetlbfs_str) - 1;
189 const char pagesize_opt[] = "pagesize=";
190 const size_t pagesize_opt_len = sizeof(pagesize_opt) - 1;
191 const char split_tok = ' ';
192 char *splitstr[_FIELDNAME_MAX];
196 FILE *fd = fopen(proc_mounts, "r");
198 rte_panic("Cannot open %s\n", proc_mounts);
200 if (default_size == 0)
201 default_size = get_default_hp_size();
203 while (fgets(buf, sizeof(buf), fd)){
204 if (rte_strsplit(buf, sizeof(buf), splitstr, _FIELDNAME_MAX,
205 split_tok) != _FIELDNAME_MAX) {
206 RTE_LOG(ERR, EAL, "Error parsing %s\n", proc_mounts);
207 break; /* return NULL */
210 /* we have a specified --huge-dir option, only examine that dir */
211 if (internal_config.hugepage_dir != NULL &&
212 strcmp(splitstr[MOUNTPT], internal_config.hugepage_dir) != 0)
215 if (strncmp(splitstr[FSTYPE], hugetlbfs_str, htlbfs_str_len) == 0){
216 const char *pagesz_str = strstr(splitstr[OPTIONS], pagesize_opt);
218 /* if no explicit page size, the default page size is compared */
219 if (pagesz_str == NULL){
220 if (hugepage_sz == default_size){
221 strlcpy(hugedir, splitstr[MOUNTPT], len);
226 /* there is an explicit page size, so check it */
228 uint64_t pagesz = rte_str_to_size(&pagesz_str[pagesize_opt_len]);
229 if (pagesz == hugepage_sz) {
230 strlcpy(hugedir, splitstr[MOUNTPT], len);
235 } /* end if strncmp hugetlbfs */
236 } /* end while fgets */
243 * Clear the hugepage directory of whatever hugepage files
244 * there are. Checks if the file is locked (i.e.
245 * if it's in use by another DPDK process).
248 clear_hugedir(const char * hugedir)
251 struct dirent *dirent;
252 int dir_fd, fd, lck_result;
253 const char filter[] = "*map_*"; /* matches hugepage files */
256 dir = opendir(hugedir);
258 RTE_LOG(ERR, EAL, "Unable to open hugepage directory %s\n",
264 dirent = readdir(dir);
266 RTE_LOG(ERR, EAL, "Unable to read hugepage directory %s\n",
271 while(dirent != NULL){
272 /* skip files that don't match the hugepage pattern */
273 if (fnmatch(filter, dirent->d_name, 0) > 0) {
274 dirent = readdir(dir);
278 /* try and lock the file */
279 fd = openat(dir_fd, dirent->d_name, O_RDONLY);
281 /* skip to next file */
283 dirent = readdir(dir);
287 /* non-blocking lock */
288 lck_result = flock(fd, LOCK_EX | LOCK_NB);
290 /* if lock succeeds, remove the file */
291 if (lck_result != -1)
292 unlinkat(dir_fd, dirent->d_name, 0);
294 dirent = readdir(dir);
304 RTE_LOG(ERR, EAL, "Error while clearing hugepage dir: %s\n",
311 compare_hpi(const void *a, const void *b)
313 const struct hugepage_info *hpi_a = a;
314 const struct hugepage_info *hpi_b = b;
316 return hpi_b->hugepage_sz - hpi_a->hugepage_sz;
320 calc_num_pages(struct hugepage_info *hpi, struct dirent *dirent)
322 uint64_t total_pages = 0;
326 * first, try to put all hugepages into relevant sockets, but
327 * if first attempts fails, fall back to collecting all pages
328 * in one socket and sorting them later
331 /* we also don't want to do this for legacy init */
332 if (!internal_config.legacy_mem)
333 for (i = 0; i < rte_socket_count(); i++) {
334 int socket = rte_socket_id_by_idx(i);
335 unsigned int num_pages =
336 get_num_hugepages_on_node(
337 dirent->d_name, socket);
338 hpi->num_pages[socket] = num_pages;
339 total_pages += num_pages;
342 * we failed to sort memory from the get go, so fall
345 if (total_pages == 0) {
346 hpi->num_pages[0] = get_num_hugepages(dirent->d_name);
349 /* for 32-bit systems, limit number of hugepages to
350 * 1GB per page size */
351 hpi->num_pages[0] = RTE_MIN(hpi->num_pages[0],
352 RTE_PGSIZE_1G / hpi->hugepage_sz);
358 hugepage_info_init(void)
359 { const char dirent_start_text[] = "hugepages-";
360 const size_t dirent_start_len = sizeof(dirent_start_text) - 1;
361 unsigned int i, num_sizes = 0;
363 struct dirent *dirent;
365 dir = opendir(sys_dir_path);
368 "Cannot open directory %s to read system hugepage info\n",
373 for (dirent = readdir(dir); dirent != NULL; dirent = readdir(dir)) {
374 struct hugepage_info *hpi;
376 if (strncmp(dirent->d_name, dirent_start_text,
377 dirent_start_len) != 0)
380 if (num_sizes >= MAX_HUGEPAGE_SIZES)
383 hpi = &internal_config.hugepage_info[num_sizes];
385 rte_str_to_size(&dirent->d_name[dirent_start_len]);
387 /* first, check if we have a mountpoint */
388 if (get_hugepage_dir(hpi->hugepage_sz,
389 hpi->hugedir, sizeof(hpi->hugedir)) < 0) {
392 num_pages = get_num_hugepages(dirent->d_name);
395 "%" PRIu32 " hugepages of size "
396 "%" PRIu64 " reserved, but no mounted "
397 "hugetlbfs found for that size\n",
398 num_pages, hpi->hugepage_sz);
399 /* if we have kernel support for reserving hugepages
400 * through mmap, and we're in in-memory mode, treat this
401 * page size as valid. we cannot be in legacy mode at
402 * this point because we've checked this earlier in the
405 #ifdef MAP_HUGE_SHIFT
406 if (internal_config.in_memory) {
407 RTE_LOG(DEBUG, EAL, "In-memory mode enabled, "
408 "hugepages of size %" PRIu64 " bytes "
409 "will be allocated anonymously\n",
411 calc_num_pages(hpi, dirent);
418 /* try to obtain a writelock */
419 hpi->lock_descriptor = open(hpi->hugedir, O_RDONLY);
421 /* if blocking lock failed */
422 if (flock(hpi->lock_descriptor, LOCK_EX) == -1) {
424 "Failed to lock hugepage directory!\n");
427 /* clear out the hugepages dir from unused pages */
428 if (clear_hugedir(hpi->hugedir) == -1)
431 calc_num_pages(hpi, dirent);
437 /* something went wrong, and we broke from the for loop above */
441 internal_config.num_hugepage_sizes = num_sizes;
443 /* sort the page directory entries by size, largest to smallest */
444 qsort(&internal_config.hugepage_info[0], num_sizes,
445 sizeof(internal_config.hugepage_info[0]), compare_hpi);
447 /* now we have all info, check we have at least one valid size */
448 for (i = 0; i < num_sizes; i++) {
449 /* pages may no longer all be on socket 0, so check all */
450 unsigned int j, num_pages = 0;
451 struct hugepage_info *hpi = &internal_config.hugepage_info[i];
453 for (j = 0; j < RTE_MAX_NUMA_NODES; j++)
454 num_pages += hpi->num_pages[j];
459 /* no valid hugepage mounts available, return error */
464 * when we initialize the hugepage info, everything goes
465 * to socket 0 by default. it will later get sorted by memory
466 * initialization procedure.
469 eal_hugepage_info_init(void)
471 struct hugepage_info *hpi, *tmp_hpi;
474 if (hugepage_info_init() < 0)
477 /* for no shared files mode, we're done */
478 if (internal_config.no_shconf)
481 hpi = &internal_config.hugepage_info[0];
483 tmp_hpi = create_shared_memory(eal_hugepage_info_path(),
484 sizeof(internal_config.hugepage_info));
485 if (tmp_hpi == NULL) {
486 RTE_LOG(ERR, EAL, "Failed to create shared memory!\n");
490 memcpy(tmp_hpi, hpi, sizeof(internal_config.hugepage_info));
492 /* we've copied file descriptors along with everything else, but they
493 * will be invalid in secondary process, so overwrite them
495 for (i = 0; i < RTE_DIM(internal_config.hugepage_info); i++) {
496 struct hugepage_info *tmp = &tmp_hpi[i];
497 tmp->lock_descriptor = -1;
500 if (munmap(tmp_hpi, sizeof(internal_config.hugepage_info)) < 0) {
501 RTE_LOG(ERR, EAL, "Failed to unmap shared memory!\n");
507 int eal_hugepage_info_read(void)
509 struct hugepage_info *hpi = &internal_config.hugepage_info[0];
510 struct hugepage_info *tmp_hpi;
512 tmp_hpi = open_shared_memory(eal_hugepage_info_path(),
513 sizeof(internal_config.hugepage_info));
514 if (tmp_hpi == NULL) {
515 RTE_LOG(ERR, EAL, "Failed to open shared memory!\n");
519 memcpy(hpi, tmp_hpi, sizeof(internal_config.hugepage_info));
521 if (munmap(tmp_hpi, sizeof(internal_config.hugepage_info)) < 0) {
522 RTE_LOG(ERR, EAL, "Failed to unmap shared memory!\n");