| /* (C) 2009-2017 by Harald Welte <laforge@gnumonks.org> |
| * |
| * All Rights Reserved |
| * |
| * SPDX-License-Identifier: GPL-2.0+ |
| * |
| * 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. |
| * |
| */ |
| |
| /*! \addtogroup rate_ctr |
| * @{ |
| * Counters about events and their event rates. |
| * |
| * As \ref osmo_counter and \ref osmo_stat_item are concerned only with |
| * a single given value that may be increased/decreased, or the difference |
| * to one given previous value, this module adds some support for keeping |
| * long term information about a given event rate. |
| * |
| * A \ref rate_ctr keeps information on the amount of events per second, |
| * per minute, per hour and per day. |
| * |
| * \ref rate_ctr come in groups: An application describes a group of counters |
| * with their names and identities once in a (typically const) \ref |
| * rate_ctr_group_desc. |
| * |
| * As objects (such as e.g. a subscriber or a PDP context) are |
| * allocated dynamically at runtime, the application calls \ref |
| * rate_ctr_group_alloc with a refernce to the \ref |
| * rate_ctr_group_desc, which causes the library to allocate one set of |
| * \ref rate_ctr: One for each in the group. |
| * |
| * The application then uses functions like \ref rate_ctr_add or \ref |
| * rate_ctr_inc to increment the value as certain events (e.g. location |
| * update) happens. |
| * |
| * The library internally keeps a timer once per second which iterates |
| * over all registered counters and which updates the per-second, |
| * per-minute, per-hour and per-day averages based on the current |
| * value. |
| * |
| * The counters can be reported using \ref stats or by VTY |
| * introspection, as well as by any application-specific code accessing |
| * the \ref rate_ctr.intv array directly. |
| * |
| * \file rate_ctr.c */ |
| |
| #include <errno.h> |
| #include <stdbool.h> |
| #include <stdint.h> |
| #include <string.h> |
| #include <unistd.h> |
| #include <inttypes.h> |
| |
| #include <osmocom/core/utils.h> |
| #include <osmocom/core/linuxlist.h> |
| #include <osmocom/core/talloc.h> |
| #include <osmocom/core/select.h> |
| #include <osmocom/core/rate_ctr.h> |
| #include <osmocom/core/logging.h> |
| |
| static LLIST_HEAD(rate_ctr_groups); |
| |
| static void *tall_rate_ctr_ctx; |
| |
| |
| static bool rate_ctrl_group_desc_validate(const struct rate_ctr_group_desc *desc) |
| { |
| unsigned int i; |
| const struct rate_ctr_desc *ctr_desc; |
| |
| if (!desc) { |
| LOGP(DLGLOBAL, LOGL_ERROR, "NULL is not a valid counter group descriptor\n"); |
| return false; |
| } |
| ctr_desc = desc->ctr_desc; |
| |
| DEBUGP(DLGLOBAL, "validating counter group %p(%s) with %u counters\n", desc, |
| desc->group_name_prefix, desc->num_ctr); |
| |
| if (!osmo_identifier_valid(desc->group_name_prefix)) { |
| LOGP(DLGLOBAL, LOGL_ERROR, "'%s' is not a valid counter group identifier\n", |
| desc->group_name_prefix); |
| return false; |
| } |
| |
| for (i = 0; i < desc->num_ctr; i++) { |
| if (!osmo_identifier_valid(ctr_desc[i].name)) { |
| LOGP(DLGLOBAL, LOGL_ERROR, "'%s' is not a valid counter identifier\n", |
| ctr_desc[i].name); |
| return false; |
| } |
| } |
| |
| return true; |
| } |
| |
| /* return 'in' if it doesn't contain any '.'; otherwise allocate a copy and |
| * replace all '.' with ':' */ |
| static char *mangle_identifier_ifneeded(const void *ctx, const char *in) |
| { |
| char *out; |
| unsigned int i; |
| bool modified = false; |
| |
| if (!in) |
| return NULL; |
| |
| if (!strchr(in, '.')) |
| return (char *)in; |
| |
| out = talloc_strdup(ctx, in); |
| OSMO_ASSERT(out); |
| |
| for (i = 0; i < strlen(out); i++) { |
| if (out[i] == '.') { |
| out[i] = ':'; |
| modified = true; |
| } |
| } |
| |
| if (modified) |
| LOGP(DLGLOBAL, LOGL_NOTICE, "counter group name mangled: '%s' -> '%s'\n", |
| in, out); |
| |
| return out; |
| } |
| |
| /* "mangle" a rate counter group descriptor, i.e. replace any '.' with ':' */ |
| static struct rate_ctr_group_desc * |
| rate_ctr_group_desc_mangle(void *ctx, const struct rate_ctr_group_desc *desc) |
| { |
| struct rate_ctr_group_desc *desc_new = talloc_zero(ctx, struct rate_ctr_group_desc); |
| int i; |
| |
| OSMO_ASSERT(desc_new); |
| |
| LOGP(DLGLOBAL, LOGL_INFO, "Needed to mangle counter group '%s' names: it is still using '.' as " |
| "separator, which is not allowed. please consider updating the application\n", |
| desc->group_name_prefix); |
| |
| /* mangle the name_prefix but copy/keep the rest */ |
| desc_new->group_name_prefix = mangle_identifier_ifneeded(desc_new, desc->group_name_prefix); |
| desc_new->group_description = desc->group_description; |
| desc_new->class_id = desc->class_id; |
| desc_new->num_ctr = desc->num_ctr; |
| desc_new->ctr_desc = talloc_array(desc_new, struct rate_ctr_desc, desc_new->num_ctr); |
| OSMO_ASSERT(desc_new->ctr_desc); |
| |
| for (i = 0; i < desc->num_ctr; i++) { |
| struct rate_ctr_desc *ctrd_new = (struct rate_ctr_desc *) desc_new->ctr_desc; |
| const struct rate_ctr_desc *ctrd = desc->ctr_desc; |
| |
| if (!ctrd[i].name) { |
| LOGP(DLGLOBAL, LOGL_ERROR, "counter group '%s'[%d] == NULL, aborting\n", |
| desc->group_name_prefix, i); |
| goto err_free; |
| } |
| |
| ctrd_new[i].name = mangle_identifier_ifneeded(desc_new->ctr_desc, ctrd[i].name); |
| ctrd_new[i].description = ctrd[i].description; |
| } |
| |
| if (!rate_ctrl_group_desc_validate(desc_new)) { |
| /* simple mangling of identifiers ('.' -> ':') was not sufficient to render a valid |
| * descriptor, we have to bail out */ |
| LOGP(DLGLOBAL, LOGL_ERROR, "counter group '%s' still invalid after mangling\n", |
| desc->group_name_prefix); |
| goto err_free; |
| } |
| |
| return desc_new; |
| err_free: |
| talloc_free(desc_new); |
| return NULL; |
| } |
| |
| /*! Find an unused index for this rate counter group. |
| * \param[in] name Name of the counter group |
| * \returns the largest used index number + 1, or 0 if none exist yet. */ |
| static unsigned int rate_ctr_get_unused_name_idx(const char *name) |
| { |
| unsigned int idx = 0; |
| struct rate_ctr_group *ctrg; |
| |
| llist_for_each_entry(ctrg, &rate_ctr_groups, list) { |
| if (!ctrg->desc) |
| continue; |
| |
| if (strcmp(ctrg->desc->group_name_prefix, name)) |
| continue; |
| |
| if (idx <= ctrg->idx) |
| idx = ctrg->idx + 1; |
| } |
| return idx; |
| } |
| |
| /*! Allocate a new group of counters according to description |
| * \param[in] ctx parent talloc context |
| * \param[in] desc Rate counter group description |
| * \param[in] idx Index of new counter group |
| */ |
| struct rate_ctr_group *rate_ctr_group_alloc(void *ctx, |
| const struct rate_ctr_group_desc *desc, |
| unsigned int idx) |
| { |
| unsigned int size; |
| struct rate_ctr_group *group; |
| |
| if (rate_ctr_get_group_by_name_idx(desc->group_name_prefix, idx)) { |
| unsigned int new_idx = rate_ctr_get_unused_name_idx(desc->group_name_prefix); |
| LOGP(DLGLOBAL, LOGL_ERROR, "counter group '%s' already exists for index %u," |
| " instead using index %u. This is a software bug that needs fixing.\n", |
| desc->group_name_prefix, idx, new_idx); |
| idx = new_idx; |
| } |
| |
| size = sizeof(struct rate_ctr_group) + |
| desc->num_ctr * sizeof(struct rate_ctr); |
| |
| if (!ctx) |
| ctx = tall_rate_ctr_ctx; |
| |
| group = talloc_zero_size(ctx, size); |
| if (!group) |
| return NULL; |
| |
| /* attempt to mangle all '.' in identifiers to ':' for backwards compat */ |
| if (!rate_ctrl_group_desc_validate(desc)) { |
| desc = rate_ctr_group_desc_mangle(group, desc); |
| if (!desc) { |
| talloc_free(group); |
| return NULL; |
| } |
| } |
| |
| group->desc = desc; |
| group->idx = idx; |
| |
| llist_add(&group->list, &rate_ctr_groups); |
| |
| return group; |
| } |
| |
| /*! Free the memory for the specified group of counters */ |
| void rate_ctr_group_free(struct rate_ctr_group *grp) |
| { |
| if (!grp) |
| return; |
| |
| if (!llist_empty(&grp->list)) |
| llist_del(&grp->list); |
| talloc_free(grp); |
| } |
| |
| /*! Get rate counter from group, identified by index idx |
| * \param[in] grp Rate counter group |
| * \param[in] idx Index of the counter to retrieve |
| * \returns rate counter requested |
| */ |
| struct rate_ctr *rate_ctr_group_get_ctr(struct rate_ctr_group *grp, unsigned int idx) |
| { |
| return &grp->ctr[idx]; |
| } |
| |
| /*! Set a name for the group of counters be used instead of index value |
| at report time. |
| * \param[in] grp Rate counter group |
| * \param[in] name Name identifier to assign to the rate counter group |
| */ |
| void rate_ctr_group_set_name(struct rate_ctr_group *grp, const char *name) |
| { |
| osmo_talloc_replace_string(grp, &grp->name, name); |
| } |
| |
| /*! Add a number to the counter */ |
| void rate_ctr_add(struct rate_ctr *ctr, int inc) |
| { |
| ctr->current += inc; |
| } |
| |
| /*! Return the counter difference since the last call to this function */ |
| int64_t rate_ctr_difference(struct rate_ctr *ctr) |
| { |
| int64_t result = ctr->current - ctr->previous; |
| ctr->previous = ctr->current; |
| |
| return result; |
| } |
| |
| /* TODO: support update intervals > 1s */ |
| /* TODO: implement this as a special stats reporter */ |
| |
| static void interval_expired(struct rate_ctr *ctr, enum rate_ctr_intv intv) |
| { |
| /* calculate rate over last interval */ |
| ctr->intv[intv].rate = ctr->current - ctr->intv[intv].last; |
| /* save current counter for next interval */ |
| ctr->intv[intv].last = ctr->current; |
| } |
| |
| static struct osmo_fd rate_ctr_timer = { .fd = -1 }; |
| static uint64_t timer_ticks; |
| |
| /* The one-second interval has expired */ |
| static void rate_ctr_group_intv(struct rate_ctr_group *grp) |
| { |
| unsigned int i; |
| |
| for (i = 0; i < grp->desc->num_ctr; i++) { |
| struct rate_ctr *ctr = &grp->ctr[i]; |
| |
| interval_expired(ctr, RATE_CTR_INTV_SEC); |
| if ((timer_ticks % 60) == 0) |
| interval_expired(ctr, RATE_CTR_INTV_MIN); |
| if ((timer_ticks % (60*60)) == 0) |
| interval_expired(ctr, RATE_CTR_INTV_HOUR); |
| if ((timer_ticks % (24*60*60)) == 0) |
| interval_expired(ctr, RATE_CTR_INTV_DAY); |
| } |
| } |
| |
| static int rate_ctr_timer_cb(struct osmo_fd *ofd, unsigned int what) |
| { |
| struct rate_ctr_group *ctrg; |
| uint64_t expire_count; |
| int rc; |
| |
| /* check that the timer has actually expired */ |
| if (!(what & OSMO_FD_READ)) |
| return 0; |
| |
| /* read from timerfd: number of expirations of periodic timer */ |
| rc = read(ofd->fd, (void *) &expire_count, sizeof(expire_count)); |
| if (rc < 0 && errno == EAGAIN) |
| return 0; |
| |
| OSMO_ASSERT(rc == sizeof(expire_count)); |
| |
| if (expire_count > 1) |
| LOGP(DLGLOBAL, LOGL_NOTICE, "Stats timer expire_count=%" PRIu64 ": We missed %" PRIu64 " timers\n", |
| expire_count, expire_count - 1); |
| |
| do { /* Increment number of ticks before we calculate intervals, |
| * as a counter value of 0 would already wrap all counters */ |
| timer_ticks++; |
| llist_for_each_entry(ctrg, &rate_ctr_groups, list) |
| rate_ctr_group_intv(ctrg); |
| } while (--expire_count); |
| |
| return 0; |
| } |
| |
| /*! Initialize the counter module. Call this once from your application. |
| * \param[in] tall_ctx Talloc context from which rate_ctr_group will be allocated |
| * \returns 0 on success; negative on error */ |
| int rate_ctr_init(void *tall_ctx) |
| { |
| struct timespec ts_interval = { .tv_sec = 1, .tv_nsec = 0 }; |
| int rc; |
| |
| /* ignore repeated initialization */ |
| if (osmo_fd_is_registered(&rate_ctr_timer)) |
| return 0; |
| |
| tall_rate_ctr_ctx = tall_ctx; |
| |
| rc = osmo_timerfd_setup(&rate_ctr_timer, rate_ctr_timer_cb, NULL); |
| if (rc < 0) { |
| LOGP(DLGLOBAL, LOGL_ERROR, "Failed to setup the timer with error code %d (fd=%d)\n", |
| rc, rate_ctr_timer.fd); |
| return rc; |
| } |
| |
| rc = osmo_timerfd_schedule(&rate_ctr_timer, NULL, &ts_interval); |
| if (rc < 0) { |
| LOGP(DLGLOBAL, LOGL_ERROR, "Failed to schedule the timer with error code %d (fd=%d)\n", |
| rc, rate_ctr_timer.fd); |
| } |
| |
| return 0; |
| } |
| |
| /*! Search for counter group based on group name and index |
| * \param[in] name Name of the counter group you're looking for |
| * \param[in] idx Index inside the counter group |
| * \returns \ref rate_ctr_group or NULL in case of error */ |
| struct rate_ctr_group *rate_ctr_get_group_by_name_idx(const char *name, const unsigned int idx) |
| { |
| struct rate_ctr_group *ctrg; |
| |
| llist_for_each_entry(ctrg, &rate_ctr_groups, list) { |
| if (!ctrg->desc) |
| continue; |
| |
| if (!strcmp(ctrg->desc->group_name_prefix, name) && |
| ctrg->idx == idx) { |
| return ctrg; |
| } |
| } |
| return NULL; |
| } |
| |
| /*! Search for counter based on group + name |
| * \param[in] ctrg pointer to \ref rate_ctr_group |
| * \param[in] name name of counter inside group |
| * \returns \ref rate_ctr or NULL in case of error |
| */ |
| const struct rate_ctr *rate_ctr_get_by_name(const struct rate_ctr_group *ctrg, const char *name) |
| { |
| int i; |
| const struct rate_ctr_desc *ctr_desc; |
| |
| if (!ctrg->desc) |
| return NULL; |
| |
| for (i = 0; i < ctrg->desc->num_ctr; i++) { |
| ctr_desc = &ctrg->desc->ctr_desc[i]; |
| |
| if (!strcmp(ctr_desc->name, name)) { |
| return &ctrg->ctr[i]; |
| } |
| } |
| return NULL; |
| } |
| |
| /*! Iterate over each counter in group and call function |
| * \param[in] ctrg counter group over which to iterate |
| * \param[in] handle_counter function pointer |
| * \param[in] data Data to hand transparently to handle_counter() |
| * \returns 0 on success; negative otherwise |
| */ |
| int rate_ctr_for_each_counter(struct rate_ctr_group *ctrg, |
| rate_ctr_handler_t handle_counter, void *data) |
| { |
| int rc = 0; |
| int i; |
| |
| for (i = 0; i < ctrg->desc->num_ctr; i++) { |
| struct rate_ctr *ctr = &ctrg->ctr[i]; |
| rc = handle_counter(ctrg, |
| ctr, &ctrg->desc->ctr_desc[i], data); |
| if (rc < 0) |
| return rc; |
| } |
| |
| return rc; |
| } |
| |
| /*! Iterate over all counter groups |
| * \param[in] handle_group function pointer of callback function |
| * \param[in] data Data to hand transparently to handle_group() |
| * \returns 0 on success; negative otherwise |
| */ |
| int rate_ctr_for_each_group(rate_ctr_group_handler_t handle_group, void *data) |
| { |
| struct rate_ctr_group *statg; |
| int rc = 0; |
| |
| llist_for_each_entry(statg, &rate_ctr_groups, list) { |
| rc = handle_group(statg, data); |
| if (rc < 0) |
| return rc; |
| } |
| |
| return rc; |
| } |
| |
| /*! Reset a rate counter back to zero |
| * \param[in] ctr counter to reset |
| */ |
| void rate_ctr_reset(struct rate_ctr *ctr) |
| { |
| memset(ctr, 0, sizeof(*ctr)); |
| } |
| |
| /*! Reset all counters in a group |
| * \param[in] ctrg counter group to reset |
| */ |
| void rate_ctr_group_reset(struct rate_ctr_group *ctrg) |
| { |
| int i; |
| |
| for (i = 0; i < ctrg->desc->num_ctr; i++) { |
| struct rate_ctr *ctr = &ctrg->ctr[i]; |
| rate_ctr_reset(ctr); |
| } |
| } |
| |
| /*! @} */ |