1 /* SPDX-License-Identifier: BSD-3-Clause
2 * Copyright(c) 2010-2014 Intel Corporation
18 #include <sys/queue.h>
21 #include <rte_memory.h>
23 #include <rte_launch.h>
24 #include <rte_per_lcore.h>
25 #include <rte_lcore.h>
26 #include <rte_debug.h>
28 #include <rte_common.h>
29 #include "rte_string_fns.h"
30 #include "eal_internal_cfg.h"
31 #include "eal_hugepages.h"
32 #include "eal_filesystem.h"
34 static const char sys_dir_path[] = "/sys/kernel/mm/hugepages";
35 static const char sys_pages_numa_dir_path[] = "/sys/devices/system/node";
38 * Uses mmap to create a shared memory area for storage of data
39 * Used in this file to store the hugepage file map on disk
42 map_shared_memory(const char *filename, const size_t mem_size, int flags)
45 int fd = open(filename, flags, 0666);
48 if (ftruncate(fd, mem_size) < 0) {
52 retval = mmap(NULL, mem_size, PROT_READ | PROT_WRITE,
59 open_shared_memory(const char *filename, const size_t mem_size)
61 return map_shared_memory(filename, mem_size, O_RDWR);
65 create_shared_memory(const char *filename, const size_t mem_size)
67 return map_shared_memory(filename, mem_size, O_RDWR | O_CREAT);
70 /* this function is only called from eal_hugepage_info_init which itself
71 * is only called from a primary process */
73 get_num_hugepages(const char *subdir)
76 long unsigned resv_pages, num_pages = 0;
77 const char *nr_hp_file = "free_hugepages";
78 const char *nr_rsvd_file = "resv_hugepages";
80 /* first, check how many reserved pages kernel reports */
81 snprintf(path, sizeof(path), "%s/%s/%s",
82 sys_dir_path, subdir, nr_rsvd_file);
83 if (eal_parse_sysfs_value(path, &resv_pages) < 0)
86 snprintf(path, sizeof(path), "%s/%s/%s",
87 sys_dir_path, subdir, nr_hp_file);
88 if (eal_parse_sysfs_value(path, &num_pages) < 0)
92 RTE_LOG(WARNING, EAL, "No free hugepages reported in %s\n",
95 /* adjust num_pages */
96 if (num_pages >= resv_pages)
97 num_pages -= resv_pages;
101 /* we want to return a uint32_t and more than this looks suspicious
103 if (num_pages > UINT32_MAX)
104 num_pages = UINT32_MAX;
110 get_num_hugepages_on_node(const char *subdir, unsigned int socket)
112 char path[PATH_MAX], socketpath[PATH_MAX];
114 unsigned long num_pages = 0;
115 const char *nr_hp_file = "free_hugepages";
117 snprintf(socketpath, sizeof(socketpath), "%s/node%u/hugepages",
118 sys_pages_numa_dir_path, socket);
120 socketdir = opendir(socketpath);
122 /* Keep calm and carry on */
125 /* Can't find socket dir, so ignore it */
129 snprintf(path, sizeof(path), "%s/%s/%s",
130 socketpath, subdir, nr_hp_file);
131 if (eal_parse_sysfs_value(path, &num_pages) < 0)
135 RTE_LOG(WARNING, EAL, "No free hugepages reported in %s\n",
139 * we want to return a uint32_t and more than this looks suspicious
142 if (num_pages > UINT32_MAX)
143 num_pages = UINT32_MAX;
149 get_default_hp_size(void)
151 const char proc_meminfo[] = "/proc/meminfo";
152 const char str_hugepagesz[] = "Hugepagesize:";
153 unsigned hugepagesz_len = sizeof(str_hugepagesz) - 1;
155 unsigned long long size = 0;
157 FILE *fd = fopen(proc_meminfo, "r");
159 rte_panic("Cannot open %s\n", proc_meminfo);
160 while(fgets(buffer, sizeof(buffer), fd)){
161 if (strncmp(buffer, str_hugepagesz, hugepagesz_len) == 0){
162 size = rte_str_to_size(&buffer[hugepagesz_len]);
168 rte_panic("Cannot get default hugepage size from %s\n", proc_meminfo);
173 get_hugepage_dir(uint64_t hugepage_sz, char *hugedir, int len)
175 enum proc_mount_fieldnames {
182 static uint64_t default_size = 0;
183 const char proc_mounts[] = "/proc/mounts";
184 const char hugetlbfs_str[] = "hugetlbfs";
185 const size_t htlbfs_str_len = sizeof(hugetlbfs_str) - 1;
186 const char pagesize_opt[] = "pagesize=";
187 const size_t pagesize_opt_len = sizeof(pagesize_opt) - 1;
188 const char split_tok = ' ';
189 char *splitstr[_FIELDNAME_MAX];
193 FILE *fd = fopen(proc_mounts, "r");
195 rte_panic("Cannot open %s\n", proc_mounts);
197 if (default_size == 0)
198 default_size = get_default_hp_size();
200 while (fgets(buf, sizeof(buf), fd)){
201 if (rte_strsplit(buf, sizeof(buf), splitstr, _FIELDNAME_MAX,
202 split_tok) != _FIELDNAME_MAX) {
203 RTE_LOG(ERR, EAL, "Error parsing %s\n", proc_mounts);
204 break; /* return NULL */
207 /* we have a specified --huge-dir option, only examine that dir */
208 if (internal_config.hugepage_dir != NULL &&
209 strcmp(splitstr[MOUNTPT], internal_config.hugepage_dir) != 0)
212 if (strncmp(splitstr[FSTYPE], hugetlbfs_str, htlbfs_str_len) == 0){
213 const char *pagesz_str = strstr(splitstr[OPTIONS], pagesize_opt);
215 /* if no explicit page size, the default page size is compared */
216 if (pagesz_str == NULL){
217 if (hugepage_sz == default_size){
218 strlcpy(hugedir, splitstr[MOUNTPT], len);
223 /* there is an explicit page size, so check it */
225 uint64_t pagesz = rte_str_to_size(&pagesz_str[pagesize_opt_len]);
226 if (pagesz == hugepage_sz) {
227 strlcpy(hugedir, splitstr[MOUNTPT], len);
232 } /* end if strncmp hugetlbfs */
233 } /* end while fgets */
240 * Clear the hugepage directory of whatever hugepage files
241 * there are. Checks if the file is locked (i.e.
242 * if it's in use by another DPDK process).
245 clear_hugedir(const char * hugedir)
248 struct dirent *dirent;
249 int dir_fd, fd, lck_result;
250 const char filter[] = "*map_*"; /* matches hugepage files */
253 dir = opendir(hugedir);
255 RTE_LOG(ERR, EAL, "Unable to open hugepage directory %s\n",
261 dirent = readdir(dir);
263 RTE_LOG(ERR, EAL, "Unable to read hugepage directory %s\n",
268 while(dirent != NULL){
269 /* skip files that don't match the hugepage pattern */
270 if (fnmatch(filter, dirent->d_name, 0) > 0) {
271 dirent = readdir(dir);
275 /* try and lock the file */
276 fd = openat(dir_fd, dirent->d_name, O_RDONLY);
278 /* skip to next file */
280 dirent = readdir(dir);
284 /* non-blocking lock */
285 lck_result = flock(fd, LOCK_EX | LOCK_NB);
287 /* if lock succeeds, remove the file */
288 if (lck_result != -1)
289 unlinkat(dir_fd, dirent->d_name, 0);
291 dirent = readdir(dir);
301 RTE_LOG(ERR, EAL, "Error while clearing hugepage dir: %s\n",
308 compare_hpi(const void *a, const void *b)
310 const struct hugepage_info *hpi_a = a;
311 const struct hugepage_info *hpi_b = b;
313 return hpi_b->hugepage_sz - hpi_a->hugepage_sz;
317 hugepage_info_init(void)
318 { const char dirent_start_text[] = "hugepages-";
319 const size_t dirent_start_len = sizeof(dirent_start_text) - 1;
320 unsigned int i, total_pages, num_sizes = 0;
322 struct dirent *dirent;
324 dir = opendir(sys_dir_path);
327 "Cannot open directory %s to read system hugepage info\n",
332 for (dirent = readdir(dir); dirent != NULL; dirent = readdir(dir)) {
333 struct hugepage_info *hpi;
335 if (strncmp(dirent->d_name, dirent_start_text,
336 dirent_start_len) != 0)
339 if (num_sizes >= MAX_HUGEPAGE_SIZES)
342 hpi = &internal_config.hugepage_info[num_sizes];
344 rte_str_to_size(&dirent->d_name[dirent_start_len]);
346 /* first, check if we have a mountpoint */
347 if (get_hugepage_dir(hpi->hugepage_sz,
348 hpi->hugedir, sizeof(hpi->hugedir)) < 0) {
351 num_pages = get_num_hugepages(dirent->d_name);
354 "%" PRIu32 " hugepages of size "
355 "%" PRIu64 " reserved, but no mounted "
356 "hugetlbfs found for that size\n",
357 num_pages, hpi->hugepage_sz);
361 /* try to obtain a writelock */
362 hpi->lock_descriptor = open(hpi->hugedir, O_RDONLY);
364 /* if blocking lock failed */
365 if (flock(hpi->lock_descriptor, LOCK_EX) == -1) {
367 "Failed to lock hugepage directory!\n");
370 /* clear out the hugepages dir from unused pages */
371 if (clear_hugedir(hpi->hugedir) == -1)
375 * first, try to put all hugepages into relevant sockets, but
376 * if first attempts fails, fall back to collecting all pages
377 * in one socket and sorting them later
380 /* we also don't want to do this for legacy init */
381 if (!internal_config.legacy_mem)
382 for (i = 0; i < rte_socket_count(); i++) {
383 int socket = rte_socket_id_by_idx(i);
384 unsigned int num_pages =
385 get_num_hugepages_on_node(
386 dirent->d_name, socket);
387 hpi->num_pages[socket] = num_pages;
388 total_pages += num_pages;
391 * we failed to sort memory from the get go, so fall
394 if (total_pages == 0)
395 hpi->num_pages[0] = get_num_hugepages(dirent->d_name);
398 /* for 32-bit systems, limit number of hugepages to
399 * 1GB per page size */
400 hpi->num_pages[0] = RTE_MIN(hpi->num_pages[0],
401 RTE_PGSIZE_1G / hpi->hugepage_sz);
408 /* something went wrong, and we broke from the for loop above */
412 internal_config.num_hugepage_sizes = num_sizes;
414 /* sort the page directory entries by size, largest to smallest */
415 qsort(&internal_config.hugepage_info[0], num_sizes,
416 sizeof(internal_config.hugepage_info[0]), compare_hpi);
418 /* now we have all info, check we have at least one valid size */
419 for (i = 0; i < num_sizes; i++) {
420 /* pages may no longer all be on socket 0, so check all */
421 unsigned int j, num_pages = 0;
422 struct hugepage_info *hpi = &internal_config.hugepage_info[i];
424 for (j = 0; j < RTE_MAX_NUMA_NODES; j++)
425 num_pages += hpi->num_pages[j];
426 if (strnlen(hpi->hugedir, sizeof(hpi->hugedir)) != 0 &&
431 /* no valid hugepage mounts available, return error */
436 * when we initialize the hugepage info, everything goes
437 * to socket 0 by default. it will later get sorted by memory
438 * initialization procedure.
441 eal_hugepage_info_init(void)
443 struct hugepage_info *hpi, *tmp_hpi;
446 if (hugepage_info_init() < 0)
449 hpi = &internal_config.hugepage_info[0];
451 tmp_hpi = create_shared_memory(eal_hugepage_info_path(),
452 sizeof(internal_config.hugepage_info));
453 if (tmp_hpi == NULL) {
454 RTE_LOG(ERR, EAL, "Failed to create shared memory!\n");
458 memcpy(tmp_hpi, hpi, sizeof(internal_config.hugepage_info));
460 /* we've copied file descriptors along with everything else, but they
461 * will be invalid in secondary process, so overwrite them
463 for (i = 0; i < RTE_DIM(internal_config.hugepage_info); i++) {
464 struct hugepage_info *tmp = &tmp_hpi[i];
465 tmp->lock_descriptor = -1;
468 if (munmap(tmp_hpi, sizeof(internal_config.hugepage_info)) < 0) {
469 RTE_LOG(ERR, EAL, "Failed to unmap shared memory!\n");
475 int eal_hugepage_info_read(void)
477 struct hugepage_info *hpi = &internal_config.hugepage_info[0];
478 struct hugepage_info *tmp_hpi;
480 tmp_hpi = open_shared_memory(eal_hugepage_info_path(),
481 sizeof(internal_config.hugepage_info));
482 if (tmp_hpi == NULL) {
483 RTE_LOG(ERR, EAL, "Failed to open shared memory!\n");
487 memcpy(hpi, tmp_hpi, sizeof(internal_config.hugepage_info));
489 if (munmap(tmp_hpi, sizeof(internal_config.hugepage_info)) < 0) {
490 RTE_LOG(ERR, EAL, "Failed to unmap shared memory!\n");