eal/linux: remove useless unlock of hugepage when clearing
[dpdk.git] / lib / librte_eal / linuxapp / eal / eal_hugepage_info.c
index 07eb7e5..485a89e 100644 (file)
@@ -1,35 +1,5 @@
-/*-
- *   BSD LICENSE
- * 
- *   Copyright(c) 2010-2013 Intel Corporation. All rights reserved.
- *   All rights reserved.
- * 
- *   Redistribution and use in source and binary forms, with or without 
- *   modification, are permitted provided that the following conditions 
- *   are met:
- * 
- *     * Redistributions of source code must retain the above copyright 
- *       notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above copyright 
- *       notice, this list of conditions and the following disclaimer in 
- *       the documentation and/or other materials provided with the 
- *       distribution.
- *     * Neither the name of Intel Corporation nor the names of its 
- *       contributors may be used to endorse or promote products derived 
- *       from this software without specific prior written permission.
- * 
- *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
- *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
- *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 
- *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 
- *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
- *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 
- *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 
- *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 
- *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
- *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
- *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- * 
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2010-2014 Intel Corporation
  */
 
 #include <string.h>
 #include <stdarg.h>
 #include <unistd.h>
 #include <errno.h>
+#include <sys/mman.h>
 #include <sys/queue.h>
+#include <sys/stat.h>
 
 #include <rte_memory.h>
-#include <rte_memzone.h>
-#include <rte_tailq.h>
 #include <rte_eal.h>
 #include <rte_launch.h>
 #include <rte_per_lcore.h>
 #include "eal_filesystem.h"
 
 static const char sys_dir_path[] = "/sys/kernel/mm/hugepages";
+static const char sys_pages_numa_dir_path[] = "/sys/devices/system/node";
 
-static int32_t
+/*
+ * Uses mmap to create a shared memory area for storage of data
+ * Used in this file to store the hugepage file map on disk
+ */
+static void *
+map_shared_memory(const char *filename, const size_t mem_size, int flags)
+{
+       void *retval;
+       int fd = open(filename, flags, 0666);
+       if (fd < 0)
+               return NULL;
+       if (ftruncate(fd, mem_size) < 0) {
+               close(fd);
+               return NULL;
+       }
+       retval = mmap(NULL, mem_size, PROT_READ | PROT_WRITE,
+                       MAP_SHARED, fd, 0);
+       close(fd);
+       return retval;
+}
+
+static void *
+open_shared_memory(const char *filename, const size_t mem_size)
+{
+       return map_shared_memory(filename, mem_size, O_RDWR);
+}
+
+static void *
+create_shared_memory(const char *filename, const size_t mem_size)
+{
+       return map_shared_memory(filename, mem_size, O_RDWR | O_CREAT);
+}
+
+/* this function is only called from eal_hugepage_info_init which itself
+ * is only called from a primary process */
+static uint32_t
 get_num_hugepages(const char *subdir)
 {
        char path[PATH_MAX];
-       long unsigned num_pages = 0;
-       const char *nr_hp_file;
-
-       /* if secondary process, just look at the number of hugepages,
-        * otherwise look at number of free hugepages */
-       if (internal_config.process_type == RTE_PROC_SECONDARY)
-               nr_hp_file = "nr_hugepages";
-       else
-               nr_hp_file = "free_hugepages";
+       long unsigned resv_pages, num_pages = 0;
+       const char *nr_hp_file = "free_hugepages";
+       const char *nr_rsvd_file = "resv_hugepages";
+
+       /* first, check how many reserved pages kernel reports */
+       snprintf(path, sizeof(path), "%s/%s/%s",
+                       sys_dir_path, subdir, nr_rsvd_file);
+       if (eal_parse_sysfs_value(path, &resv_pages) < 0)
+               return 0;
 
-       rte_snprintf(path, sizeof(path), "%s/%s/%s",
+       snprintf(path, sizeof(path), "%s/%s/%s",
                        sys_dir_path, subdir, nr_hp_file);
+       if (eal_parse_sysfs_value(path, &num_pages) < 0)
+               return 0;
+
+       if (num_pages == 0)
+               RTE_LOG(WARNING, EAL, "No free hugepages reported in %s\n",
+                               subdir);
+
+       /* adjust num_pages */
+       if (num_pages >= resv_pages)
+               num_pages -= resv_pages;
+       else if (resv_pages)
+               num_pages = 0;
 
+       /* we want to return a uint32_t and more than this looks suspicious
+        * anyway ... */
+       if (num_pages > UINT32_MAX)
+               num_pages = UINT32_MAX;
+
+       return num_pages;
+}
+
+static uint32_t
+get_num_hugepages_on_node(const char *subdir, unsigned int socket)
+{
+       char path[PATH_MAX], socketpath[PATH_MAX];
+       DIR *socketdir;
+       unsigned long num_pages = 0;
+       const char *nr_hp_file = "free_hugepages";
+
+       snprintf(socketpath, sizeof(socketpath), "%s/node%u/hugepages",
+               sys_pages_numa_dir_path, socket);
+
+       socketdir = opendir(socketpath);
+       if (socketdir) {
+               /* Keep calm and carry on */
+               closedir(socketdir);
+       } else {
+               /* Can't find socket dir, so ignore it */
+               return 0;
+       }
+
+       snprintf(path, sizeof(path), "%s/%s/%s",
+                       socketpath, subdir, nr_hp_file);
        if (eal_parse_sysfs_value(path, &num_pages) < 0)
                return 0;
 
        if (num_pages == 0)
-               RTE_LOG(ERR, EAL, "Error - no free hugepages available!\n");
+               RTE_LOG(WARNING, EAL, "No free hugepages reported in %s\n",
+                               subdir);
+
+       /*
+        * we want to return a uint32_t and more than this looks suspicious
+        * anyway ...
+        */
+       if (num_pages > UINT32_MAX)
+               num_pages = UINT32_MAX;
 
-       return (int32_t)num_pages;
+       return num_pages;
 }
 
 static uint64_t
@@ -113,8 +169,8 @@ get_default_hp_size(void)
        return size;
 }
 
-static const char *
-get_hugepage_dir(uint64_t hugepage_sz)
+static int
+get_hugepage_dir(uint64_t hugepage_sz, char *hugedir, int len)
 {
        enum proc_mount_fieldnames {
                DEVICE = 0,
@@ -132,7 +188,7 @@ get_hugepage_dir(uint64_t hugepage_sz)
        const char split_tok = ' ';
        char *splitstr[_FIELDNAME_MAX];
        char buf[BUFSIZ];
-       char *retval = NULL;
+       int retval = -1;
 
        FILE *fd = fopen(proc_mounts, "r");
        if (fd == NULL)
@@ -159,7 +215,8 @@ get_hugepage_dir(uint64_t hugepage_sz)
                        /* if no explicit page size, the default page size is compared */
                        if (pagesz_str == NULL){
                                if (hugepage_sz == default_size){
-                                       retval = strdup(splitstr[MOUNTPT]);
+                                       strlcpy(hugedir, splitstr[MOUNTPT], len);
+                                       retval = 0;
                                        break;
                                }
                        }
@@ -167,7 +224,8 @@ get_hugepage_dir(uint64_t hugepage_sz)
                        else {
                                uint64_t pagesz = rte_str_to_size(&pagesz_str[pagesize_opt_len]);
                                if (pagesz == hugepage_sz) {
-                                       retval = strdup(splitstr[MOUNTPT]);
+                                       strlcpy(hugedir, splitstr[MOUNTPT], len);
+                                       retval = 0;
                                        break;
                                }
                        }
@@ -178,13 +236,16 @@ get_hugepage_dir(uint64_t hugepage_sz)
        return retval;
 }
 
-static inline void
-swap_hpi(struct hugepage_info *a, struct hugepage_info *b)
+/*
+ * uses fstat to report the size of a file on disk
+ */
+static off_t
+get_file_size(int fd)
 {
-       char buf[sizeof(*a)];
-       memcpy(buf, a, sizeof(buf));
-       memcpy(a, b, sizeof(buf));
-       memcpy(b, buf, sizeof(buf));
+       struct stat st;
+       if (fstat(fd, &st) < 0)
+               return 0;
+       return st.st_size;
 }
 
 /*
@@ -203,7 +264,7 @@ clear_hugedir(const char * hugedir)
        /* open directory */
        dir = opendir(hugedir);
        if (!dir) {
-               RTE_LOG(INFO, EAL, "Unable to open hugepage directory %s\n",
+               RTE_LOG(ERR, EAL, "Unable to open hugepage directory %s\n",
                                hugedir);
                goto error;
        }
@@ -211,12 +272,14 @@ clear_hugedir(const char * hugedir)
 
        dirent = readdir(dir);
        if (!dirent) {
-               RTE_LOG(INFO, EAL, "Unable to read hugepage directory %s\n",
+               RTE_LOG(ERR, EAL, "Unable to read hugepage directory %s\n",
                                hugedir);
                goto error;
        }
 
        while(dirent != NULL){
+               struct flock lck = {0};
+
                /* skip files that don't match the hugepage pattern */
                if (fnmatch(filter, dirent->d_name, 0) > 0) {
                        dirent = readdir(dir);
@@ -233,13 +296,16 @@ clear_hugedir(const char * hugedir)
                }
 
                /* non-blocking lock */
-               lck_result = flock(fd, LOCK_EX | LOCK_NB);
+               lck.l_type = F_RDLCK;
+               lck.l_whence = SEEK_SET;
+               lck.l_start = 0;
+               lck.l_len = get_file_size(fd);
+
+               lck_result = fcntl(fd, F_SETLK, &lck);
 
                /* if lock succeeds, unlock and remove the file */
-               if (lck_result != -1) {
-                       flock(fd, LOCK_UN);
+               if (lck_result != -1)
                        unlinkat(dir_fd, dirent->d_name, 0);
-               }
                close (fd);
                dirent = readdir(dir);
        }
@@ -251,90 +317,197 @@ error:
        if (dir)
                closedir(dir);
 
-       RTE_LOG(INFO, EAL, "Error while clearing hugepage dir: %s\n",
+       RTE_LOG(ERR, EAL, "Error while clearing hugepage dir: %s\n",
                strerror(errno));
 
        return -1;
 }
 
-/*
- * when we initialize the hugepage info, everything goes
- * to socket 0 by default. it will later get sorted by memory
- * initialization procedure.
- */
-int
-eal_hugepage_info_init(void)
+static int
+compare_hpi(const void *a, const void *b)
 {
-       const char dirent_start_text[] = "hugepages-";
+       const struct hugepage_info *hpi_a = a;
+       const struct hugepage_info *hpi_b = b;
+
+       return hpi_b->hugepage_sz - hpi_a->hugepage_sz;
+}
+
+static int
+hugepage_info_init(void)
+{      const char dirent_start_text[] = "hugepages-";
        const size_t dirent_start_len = sizeof(dirent_start_text) - 1;
-       unsigned i, num_sizes = 0;
+       unsigned int i, total_pages, num_sizes = 0;
+       DIR *dir;
+       struct dirent *dirent;
 
-       DIR *dir = opendir(sys_dir_path);
-       if (dir == NULL)
-               rte_panic("Cannot open directory %s to read system hugepage info\n",
-                               sys_dir_path);
+       dir = opendir(sys_dir_path);
+       if (dir == NULL) {
+               RTE_LOG(ERR, EAL,
+                       "Cannot open directory %s to read system hugepage info\n",
+                       sys_dir_path);
+               return -1;
+       }
 
-       struct dirent *dirent = readdir(dir);
-       while(dirent != NULL){
-               if (strncmp(dirent->d_name, dirent_start_text, dirent_start_len) == 0){
-                       struct hugepage_info *hpi = \
-                                       &internal_config.hugepage_info[num_sizes];
-                       hpi->hugepage_sz = rte_str_to_size(&dirent->d_name[dirent_start_len]);
-                       hpi->hugedir = get_hugepage_dir(hpi->hugepage_sz);
-
-                       /* first, check if we have a mountpoint */
-                       if (hpi->hugedir == NULL){
-                               RTE_LOG(INFO, EAL, "%u hugepages of size %llu reserved, "\
-                                               "but no mounted hugetlbfs found for that size\n",
-                                               (unsigned) get_num_hugepages(dirent->d_name),
-                                               (unsigned long long)hpi->hugepage_sz);
-                       } else {
-                               /* try to obtain a writelock */
-                               hpi->lock_descriptor = open(hpi->hugedir, O_RDONLY);
-
-                               /* if blocking lock failed */
-                               if (flock(hpi->lock_descriptor, LOCK_EX) == -1) {
-                                       RTE_LOG(CRIT, EAL, "Failed to lock hugepage directory!\n");
-                                       return -1;
-                               }
-                               /* clear out the hugepages dir from unused pages */
-                               if (clear_hugedir(hpi->hugedir) == -1)
-                                       return -1;
-
-                               /* for now, put all pages into socket 0,
-                                * later they will be sorted */
-                               hpi->num_pages[0] = get_num_hugepages(dirent->d_name);
-
-#ifndef RTE_ARCH_X86_64
-                               /* for 32-bit systems, limit number of hugepages to 1GB per page size */
-                               hpi->num_pages[0] = RTE_MIN(hpi->num_pages[0],
-                                               RTE_PGSIZE_1G / hpi->hugepage_sz);
-#endif
+       for (dirent = readdir(dir); dirent != NULL; dirent = readdir(dir)) {
+               struct hugepage_info *hpi;
 
-                               num_sizes++;
-                       }
+               if (strncmp(dirent->d_name, dirent_start_text,
+                           dirent_start_len) != 0)
+                       continue;
+
+               if (num_sizes >= MAX_HUGEPAGE_SIZES)
+                       break;
+
+               hpi = &internal_config.hugepage_info[num_sizes];
+               hpi->hugepage_sz =
+                       rte_str_to_size(&dirent->d_name[dirent_start_len]);
+
+               /* first, check if we have a mountpoint */
+               if (get_hugepage_dir(hpi->hugepage_sz,
+                       hpi->hugedir, sizeof(hpi->hugedir)) < 0) {
+                       uint32_t num_pages;
+
+                       num_pages = get_num_hugepages(dirent->d_name);
+                       if (num_pages > 0)
+                               RTE_LOG(NOTICE, EAL,
+                                       "%" PRIu32 " hugepages of size "
+                                       "%" PRIu64 " reserved, but no mounted "
+                                       "hugetlbfs found for that size\n",
+                                       num_pages, hpi->hugepage_sz);
+                       continue;
                }
-               dirent = readdir(dir);
+
+               /* try to obtain a writelock */
+               hpi->lock_descriptor = open(hpi->hugedir, O_RDONLY);
+
+               /* if blocking lock failed */
+               if (flock(hpi->lock_descriptor, LOCK_EX) == -1) {
+                       RTE_LOG(CRIT, EAL,
+                               "Failed to lock hugepage directory!\n");
+                       break;
+               }
+               /* clear out the hugepages dir from unused pages */
+               if (clear_hugedir(hpi->hugedir) == -1)
+                       break;
+
+               /*
+                * first, try to put all hugepages into relevant sockets, but
+                * if first attempts fails, fall back to collecting all pages
+                * in one socket and sorting them later
+                */
+               total_pages = 0;
+               /* we also don't want to do this for legacy init */
+               if (!internal_config.legacy_mem)
+                       for (i = 0; i < rte_socket_count(); i++) {
+                               int socket = rte_socket_id_by_idx(i);
+                               unsigned int num_pages =
+                                               get_num_hugepages_on_node(
+                                                       dirent->d_name, socket);
+                               hpi->num_pages[socket] = num_pages;
+                               total_pages += num_pages;
+                       }
+               /*
+                * we failed to sort memory from the get go, so fall
+                * back to old way
+                */
+               if (total_pages == 0)
+                       hpi->num_pages[0] = get_num_hugepages(dirent->d_name);
+
+#ifndef RTE_ARCH_64
+               /* for 32-bit systems, limit number of hugepages to
+                * 1GB per page size */
+               hpi->num_pages[0] = RTE_MIN(hpi->num_pages[0],
+                                           RTE_PGSIZE_1G / hpi->hugepage_sz);
+#endif
+
+               num_sizes++;
        }
        closedir(dir);
+
+       /* something went wrong, and we broke from the for loop above */
+       if (dirent != NULL)
+               return -1;
+
        internal_config.num_hugepage_sizes = num_sizes;
 
        /* sort the page directory entries by size, largest to smallest */
-       for (i = 0; i < num_sizes; i++){
-               unsigned j;
-               for (j = i+1; j < num_sizes; j++)
-                       if (internal_config.hugepage_info[j-1].hugepage_sz < \
-                                       internal_config.hugepage_info[j].hugepage_sz)
-                               swap_hpi(&internal_config.hugepage_info[j-1],
-                                               &internal_config.hugepage_info[j]);
-       }
+       qsort(&internal_config.hugepage_info[0], num_sizes,
+             sizeof(internal_config.hugepage_info[0]), compare_hpi);
 
        /* now we have all info, check we have at least one valid size */
-       for (i = 0; i < num_sizes; i++)
-               if (internal_config.hugepage_info[i].hugedir != NULL &&
-                               internal_config.hugepage_info[i].num_pages[0] > 0)
+       for (i = 0; i < num_sizes; i++) {
+               /* pages may no longer all be on socket 0, so check all */
+               unsigned int j, num_pages = 0;
+               struct hugepage_info *hpi = &internal_config.hugepage_info[i];
+
+               for (j = 0; j < RTE_MAX_NUMA_NODES; j++)
+                       num_pages += hpi->num_pages[j];
+               if (strnlen(hpi->hugedir, sizeof(hpi->hugedir)) != 0 &&
+                               num_pages > 0)
                        return 0;
+       }
 
        /* no valid hugepage mounts available, return error */
        return -1;
 }
+
+/*
+ * when we initialize the hugepage info, everything goes
+ * to socket 0 by default. it will later get sorted by memory
+ * initialization procedure.
+ */
+int
+eal_hugepage_info_init(void)
+{
+       struct hugepage_info *hpi, *tmp_hpi;
+       unsigned int i;
+
+       if (hugepage_info_init() < 0)
+               return -1;
+
+       hpi = &internal_config.hugepage_info[0];
+
+       tmp_hpi = create_shared_memory(eal_hugepage_info_path(),
+                       sizeof(internal_config.hugepage_info));
+       if (tmp_hpi == NULL) {
+               RTE_LOG(ERR, EAL, "Failed to create shared memory!\n");
+               return -1;
+       }
+
+       memcpy(tmp_hpi, hpi, sizeof(internal_config.hugepage_info));
+
+       /* we've copied file descriptors along with everything else, but they
+        * will be invalid in secondary process, so overwrite them
+        */
+       for (i = 0; i < RTE_DIM(internal_config.hugepage_info); i++) {
+               struct hugepage_info *tmp = &tmp_hpi[i];
+               tmp->lock_descriptor = -1;
+       }
+
+       if (munmap(tmp_hpi, sizeof(internal_config.hugepage_info)) < 0) {
+               RTE_LOG(ERR, EAL, "Failed to unmap shared memory!\n");
+               return -1;
+       }
+       return 0;
+}
+
+int eal_hugepage_info_read(void)
+{
+       struct hugepage_info *hpi = &internal_config.hugepage_info[0];
+       struct hugepage_info *tmp_hpi;
+
+       tmp_hpi = open_shared_memory(eal_hugepage_info_path(),
+                                 sizeof(internal_config.hugepage_info));
+       if (tmp_hpi == NULL) {
+               RTE_LOG(ERR, EAL, "Failed to open shared memory!\n");
+               return -1;
+       }
+
+       memcpy(hpi, tmp_hpi, sizeof(internal_config.hugepage_info));
+
+       if (munmap(tmp_hpi, sizeof(internal_config.hugepage_info)) < 0) {
+               RTE_LOG(ERR, EAL, "Failed to unmap shared memory!\n");
+               return -1;
+       }
+       return 0;
+}