From 9732cb4a92a883c7e9f7dcd928b6e22976a797ca Mon Sep 17 00:00:00 2001 From: Jacob Erlbeck Date: Thu, 1 Oct 2015 20:43:53 +0200 Subject: stats: Add stat_item for value monitoring This commit adds instrumentation function to gather measurement and statistical values similar to counter groups. Multiple values can be stored per item, which can be retrieved in FIFO order. Getting values from the item does not modify its state to allow for multiple independant backends (e.g. VTY and statd). When a new value is set, the oldest value gets silently overwritten. Lost values are skipped when getting values from the item. Sponsored-by: On-Waves ehf --- src/Makefile.am | 2 +- src/stat_item.c | 215 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 216 insertions(+), 1 deletion(-) create mode 100644 src/stat_item.c (limited to 'src') diff --git a/src/Makefile.am b/src/Makefile.am index 4bf3408e..93fc3833 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -15,7 +15,7 @@ libosmocore_la_SOURCES = timer.c select.c signal.c msgb.c bits.c \ gsmtap_util.c crc16.c panic.c backtrace.c \ conv.c application.c rbtree.c strrb.c \ loggingrb.c crc8gen.c crc16gen.c crc32gen.c crc64gen.c \ - macaddr.c + macaddr.c stat_item.c BUILT_SOURCES = crc8gen.c crc16gen.c crc32gen.c crc64gen.c diff --git a/src/stat_item.c b/src/stat_item.c new file mode 100644 index 00000000..7b169ea0 --- /dev/null +++ b/src/stat_item.c @@ -0,0 +1,215 @@ +/* utility routines for keeping conters about events and the event rates */ + +/* (C) 2015 by Sysmocom s.f.m.c. GmbH + * (C) 2009-2010 by Harald Welte + * + * All Rights Reserved + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + * + */ + +/*! \addtogroup stat_item + * @{ + */ + +/*! \file stat_item.c */ + + +#include +#include + +#include +#include +#include +#include +#include + +static LLIST_HEAD(stat_item_groups); + +static void *tall_stat_item_ctx; + +/*! \brief Allocate a new group of counters according to description + * \param[in] ctx \ref talloc context + * \param[in] desc Statistics item group description + * \param[in] idx Index of new stat item group + */ +struct stat_item_group *stat_item_group_alloc(void *ctx, + const struct stat_item_group_desc *desc, + unsigned int idx) +{ + unsigned int group_size; + unsigned int items_size = 0; + unsigned int item_idx; + void *items; + + struct stat_item_group *group; + + group_size = sizeof(struct stat_item_group) + + desc->num_items * sizeof(struct stat_item *); + + if (!ctx) + ctx = tall_stat_item_ctx; + + group = talloc_zero_size(ctx, group_size); + if (!group) + return NULL; + + group->desc = desc; + group->idx = idx; + + /* Get combined size of all items */ + for (item_idx = 0; item_idx < desc->num_items; item_idx++) { + unsigned int size; + size = sizeof(struct stat_item) + + sizeof(int32_t) * desc->item_desc[item_idx].num_values; + /* Align to pointer size */ + size = (size + sizeof(void *) - 1) & ~(sizeof(void *) - 1); + + /* Store offsets into the item array */ + group->items[item_idx] = (void *)items_size; + + items_size += size; + } + + items = talloc_zero_size(group, items_size); + if (!items) { + talloc_free(group); + return NULL; + } + + /* Update item pointers */ + for (item_idx = 0; item_idx < desc->num_items; item_idx++) { + struct stat_item *item = (struct stat_item *) + ((uint8_t *)items + (int)group->items[item_idx]); + unsigned int i; + + group->items[item_idx] = item; + item->last_offs = desc->item_desc[item_idx].num_values - 1; + item->last_value_index = -1; + item->desc = &desc->item_desc[item_idx]; + + for (i = 0; i <= item->last_offs; i++) + item->values[i] = desc->item_desc[item_idx].default_value; + } + + llist_add(&group->list, &stat_item_groups); + + return group; +} + +/*! \brief Free the memory for the specified group of counters */ +void stat_item_group_free(struct stat_item_group *grp) +{ + llist_del(&grp->list); + talloc_free(grp); +} + +void stat_item_set(struct stat_item *item, int32_t value) +{ + item->last_offs += 1; + if (item->last_offs >= item->desc->num_values) + item->last_offs = 0; + + item->last_value_index += 1; + + item->values[item->last_offs] = value; +} + +int stat_item_get_next(const struct stat_item *item, int32_t *next_idx, + int32_t *value) +{ + int32_t delta = item->last_value_index + 1 - *next_idx; + int n_values = 0; + int next_offs; + + if (delta == 0) + /* All items have been read */ + return 0; + + if (delta < 0 || delta > item->desc->num_values) { + n_values = delta - item->desc->num_values; + delta = item->desc->num_values; + } + + next_offs = item->last_offs + 1 - delta; + if (next_offs < 0) + next_offs += item->desc->num_values; + + *value = item->values[next_offs]; + + n_values += 1; + delta -= 1; + *next_idx = item->last_value_index + 1 - delta; + + return n_values; +} + +/*! \brief Skip all values and update idx accordingly */ +int stat_item_discard(const struct stat_item *item, int32_t *idx) +{ + int discarded = item->last_value_index + 1 - *idx; + *idx = item->last_value_index + 1; + + return discarded; +} + + +/*! \brief Initialize the stat item module */ +int stat_item_init(void *tall_ctx) +{ + tall_stat_item_ctx = tall_ctx; + + return 0; +} + +/*! \brief Search for item group based on group name and index */ +struct stat_item_group *stat_item_get_group_by_name_idx( + const char *name, const unsigned int idx) +{ + struct stat_item_group *statg; + + llist_for_each_entry(statg, &stat_item_groups, list) { + if (!statg->desc) + continue; + + if (!strcmp(statg->desc->group_name_prefix, name) && + statg->idx == idx) + return statg; + } + return NULL; +} + +/*! \brief Search for item group based on group name */ +const struct stat_item *stat_item_get_by_name( + const struct stat_item_group *statg, const char *name) +{ + int i; + const struct stat_item_desc *item_desc; + + if (!statg->desc) + return NULL; + + for (i = 0; i < statg->desc->num_items; i++) { + item_desc = &statg->desc->item_desc[i]; + + if (!strcmp(item_desc->name, name)) { + return statg->items[i]; + } + } + return NULL; +} + +/*! @} */ -- cgit v1.2.3