diff options
Diffstat (limited to 'src/vlib/linux/sysfs.c')
| -rw-r--r-- | src/vlib/linux/sysfs.c | 250 |
1 files changed, 250 insertions, 0 deletions
diff --git a/src/vlib/linux/sysfs.c b/src/vlib/linux/sysfs.c new file mode 100644 index 00000000000..f92f9ef564e --- /dev/null +++ b/src/vlib/linux/sysfs.c @@ -0,0 +1,250 @@ +/* + * Copyright (c) 2017 Cisco and/or its affiliates. + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at: + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include <vlib/vlib.h> +#include <vlib/unix/unix.h> + +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <dirent.h> + +clib_error_t * +vlib_sysfs_write (char *file_name, char *fmt, ...) +{ + u8 *s; + int fd; + clib_error_t *error = 0; + + fd = open (file_name, O_WRONLY); + if (fd < 0) + return clib_error_return_unix (0, "open `%s'", file_name); + + va_list va; + va_start (va, fmt); + s = va_format (0, fmt, &va); + va_end (va); + + if (write (fd, s, vec_len (s)) < 0) + error = clib_error_return_unix (0, "write `%s'", file_name); + + vec_free (s); + close (fd); + return error; +} + +clib_error_t * +vlib_sysfs_read (char *file_name, char *fmt, ...) +{ + unformat_input_t input; + u8 *s = 0; + int fd; + ssize_t sz; + uword result; + + fd = open (file_name, O_RDONLY); + if (fd < 0) + return clib_error_return_unix (0, "open `%s'", file_name); + + vec_validate (s, 4095); + + sz = read (fd, s, vec_len (s)); + if (sz < 0) + { + close (fd); + vec_free (s); + return clib_error_return_unix (0, "read `%s'", file_name); + } + + _vec_len (s) = sz; + unformat_init_vector (&input, s); + + va_list va; + va_start (va, fmt); + result = va_unformat (&input, fmt, &va); + va_end (va); + + vec_free (s); + close (fd); + + if (result == 0) + return clib_error_return (0, "unformat error"); + + return 0; +} + +u8 * +vlib_sysfs_link_to_name (char *link) +{ + char *p, buffer[64]; + unformat_input_t in; + u8 *s = 0; + int r; + + r = readlink (link, buffer, sizeof (buffer) - 1); + + if (r < 0) + return 0; + + buffer[r] = 0; + p = strrchr (buffer, '/'); + + if (!p) + return 0; + + unformat_init_string (&in, p + 1, strlen (p + 1)); + if (unformat (&in, "%s", &s) != 1) + clib_unix_warning ("no string?"); + unformat_free (&in); + + return s; +} + +clib_error_t * +vlib_sysfs_set_nr_hugepages (unsigned int numa_node, int page_size, int nr) +{ + clib_error_t *error = 0; + struct stat sb; + u8 *p = 0; + + p = format (p, "/sys/devices/system/node/node%u%c", numa_node, 0); + + if (stat ((char *) p, &sb) == 0) + { + if (S_ISDIR (sb.st_mode) == 0) + { + error = clib_error_return (0, "'%s' is not directory", p); + goto done; + } + } + else if (numa_node == 0) + { + vec_reset_length (p); + p = format (p, "/sys/kernel/mm%c", 0); + if (stat ((char *) p, &sb) < 0 || S_ISDIR (sb.st_mode) == 0) + { + error = clib_error_return (0, "'%s' does not exist or it is not " + "directory", p); + goto done; + } + } + else + { + error = clib_error_return (0, "'%s' does not exist", p); + goto done; + } + + _vec_len (p) -= 1; + p = format (p, "/hugepages/hugepages-%ukB/nr_hugepages%c", page_size, 0); + vlib_sysfs_write ((char *) p, "%d", nr); + +done: + vec_free (p); + return error; +} + + +static clib_error_t * +vlib_sysfs_get_xxx_hugepages (char *type, unsigned int numa_node, + int page_size, int *val) +{ + clib_error_t *error = 0; + struct stat sb; + u8 *p = 0; + + p = format (p, "/sys/devices/system/node/node%u%c", numa_node, 0); + + if (stat ((char *) p, &sb) == 0) + { + if (S_ISDIR (sb.st_mode) == 0) + { + error = clib_error_return (0, "'%s' is not directory", p); + goto done; + } + } + else if (numa_node == 0) + { + vec_reset_length (p); + p = format (p, "/sys/kernel/mm%c", 0); + if (stat ((char *) p, &sb) < 0 || S_ISDIR (sb.st_mode) == 0) + { + error = clib_error_return (0, "'%s' does not exist or it is not " + "directory", p); + goto done; + } + } + else + { + error = clib_error_return (0, "'%s' does not exist", p); + goto done; + } + + _vec_len (p) -= 1; + p = format (p, "/hugepages/hugepages-%ukB/%s_hugepages%c", page_size, + type, 0); + error = vlib_sysfs_read ((char *) p, "%d", val); + +done: + vec_free (p); + return error; +} + +clib_error_t * +vlib_sysfs_get_free_hugepages (unsigned int numa_node, int page_size, int *v) +{ + return vlib_sysfs_get_xxx_hugepages ("free", numa_node, page_size, v); +} + +clib_error_t * +vlib_sysfs_get_nr_hugepages (unsigned int numa_node, int page_size, int *v) +{ + return vlib_sysfs_get_xxx_hugepages ("nr", numa_node, page_size, v); +} + +clib_error_t * +vlib_sysfs_get_surplus_hugepages (unsigned int numa_node, int page_size, + int *v) +{ + return vlib_sysfs_get_xxx_hugepages ("surplus", numa_node, page_size, v); +} + +clib_error_t * +vlib_sysfs_prealloc_hugepages (unsigned int numa_node, int page_size, int nr) +{ + clib_error_t *error = 0; + int n, needed; + error = vlib_sysfs_get_free_hugepages (numa_node, page_size, &n); + if (error) + return error; + needed = nr - n; + if (needed <= 0) + return 0; + + error = vlib_sysfs_get_nr_hugepages (numa_node, page_size, &n); + if (error) + return error; + clib_warning ("pre-allocating %u additional %uK hugepages on numa node %u", + needed, page_size, numa_node); + return vlib_sysfs_set_nr_hugepages (numa_node, page_size, n + needed); +} + + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |