Neels Hofmeyr | 25c9741 | 2021-11-13 23:19:33 +0100 | [diff] [blame] | 1 | /*! \file foo.c |
| 2 | * Report the cumulative counter of time for which a flag is true as rate counter. |
| 3 | */ |
| 4 | /* Copyright (C) 2021 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de> |
| 5 | * |
| 6 | * All Rights Reserved |
| 7 | * |
| 8 | * Author: Neels Hofmeyr <nhofmeyr@sysmocom.de> |
| 9 | * |
| 10 | * This program is free software; you can redistribute it and/or modify |
| 11 | * it under the terms of the GNU Affero General Public License as published by |
| 12 | * the Free Software Foundation; either version 3 of the License, or |
| 13 | * (at your option) any later version. |
| 14 | * |
| 15 | * This program is distributed in the hope that it will be useful, |
| 16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 18 | * GNU Affero General Public License for more details. |
| 19 | * |
| 20 | * You should have received a copy of the GNU Affero General Public License |
| 21 | * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| 22 | * |
| 23 | */ |
| 24 | |
| 25 | /*! \addtogroup time_cc |
| 26 | * |
| 27 | * Report the cumulative counter of time for which a flag is true as rate counter. |
| 28 | * |
| 29 | * Useful for reporting cumulative time counters as defined in 3GPP TS 52.402, for example allAvailableSDCCHAllocated, |
| 30 | * allAvailableTCHAllocated, availablePDCHAllocatedTime. |
| 31 | * |
| 32 | * For a usage example, see the description of struct osmo_time_cc. |
| 33 | * |
| 34 | * @{ |
| 35 | * \file time_cc.c |
| 36 | */ |
| 37 | #include "config.h" |
| 38 | #ifdef HAVE_CLOCK_GETTIME |
| 39 | |
| 40 | #include <limits.h> |
| 41 | #include <time.h> |
| 42 | |
| 43 | #include <osmocom/core/tdef.h> |
| 44 | #include <osmocom/core/rate_ctr.h> |
| 45 | #include <osmocom/core/time_cc.h> |
| 46 | |
| 47 | #define GRAN_USEC(TIME_CC) ((TIME_CC)->cfg.gran_usec ? : 1000000) |
| 48 | #define ROUND_THRESHOLD_USEC(TIME_CC) ((TIME_CC)->cfg.round_threshold_usec ? \ |
| 49 | OSMO_MIN((TIME_CC)->cfg.round_threshold_usec, GRAN_USEC(TIME_CC)) \ |
| 50 | : (GRAN_USEC(TIME_CC) / 2)) |
| 51 | |
Harald Welte | e61d459 | 2022-11-03 11:05:58 +0100 | [diff] [blame] | 52 | static uint64_t time_now_usec(void) |
Neels Hofmeyr | 25c9741 | 2021-11-13 23:19:33 +0100 | [diff] [blame] | 53 | { |
| 54 | struct timespec tp; |
| 55 | if (osmo_clock_gettime(CLOCK_MONOTONIC, &tp)) |
| 56 | return 0; |
| 57 | return (uint64_t)tp.tv_sec * 1000000 + tp.tv_nsec / 1000; |
| 58 | } |
| 59 | |
| 60 | static void osmo_time_cc_forget_sum(struct osmo_time_cc *tc, uint64_t now); |
| 61 | |
| 62 | static void osmo_time_cc_update_from_tdef(struct osmo_time_cc *tc, uint64_t now) |
| 63 | { |
| 64 | bool do_forget_sum = false; |
| 65 | if (!tc->cfg.T_defs) |
| 66 | return; |
| 67 | if (tc->cfg.T_gran) { |
| 68 | uint64_t was = GRAN_USEC(tc); |
| 69 | tc->cfg.gran_usec = osmo_tdef_get(tc->cfg.T_defs, tc->cfg.T_gran, OSMO_TDEF_US, -1); |
| 70 | if (was != GRAN_USEC(tc)) |
| 71 | do_forget_sum = true; |
| 72 | } |
| 73 | if (tc->cfg.T_round_threshold) |
| 74 | tc->cfg.round_threshold_usec = osmo_tdef_get(tc->cfg.T_defs, tc->cfg.T_round_threshold, |
| 75 | OSMO_TDEF_US, -1); |
| 76 | if (tc->cfg.T_forget_sum) { |
| 77 | uint64_t was = tc->cfg.forget_sum_usec; |
| 78 | tc->cfg.forget_sum_usec = osmo_tdef_get(tc->cfg.T_defs, tc->cfg.T_forget_sum, OSMO_TDEF_US, -1); |
| 79 | if (tc->cfg.forget_sum_usec && was != tc->cfg.forget_sum_usec) |
| 80 | do_forget_sum = true; |
| 81 | } |
| 82 | |
| 83 | if (do_forget_sum && tc->sum) |
| 84 | osmo_time_cc_forget_sum(tc, now); |
| 85 | } |
| 86 | |
| 87 | static void osmo_time_cc_schedule_timer(struct osmo_time_cc *tc, uint64_t now); |
| 88 | |
| 89 | /*! Clear out osmo_timer and internal counting state of struct osmo_time_cc. The .cfg remains unaffected. After calling, |
| 90 | * the osmo_time_cc instance can be used again to accumulate state as if it had just been initialized. */ |
| 91 | void osmo_time_cc_cleanup(struct osmo_time_cc *tc) |
| 92 | { |
| 93 | osmo_timer_del(&tc->timer); |
| 94 | *tc = (struct osmo_time_cc){ |
| 95 | .cfg = tc->cfg, |
| 96 | }; |
| 97 | } |
| 98 | |
| 99 | static void osmo_time_cc_start(struct osmo_time_cc *tc, uint64_t now) |
| 100 | { |
| 101 | osmo_time_cc_cleanup(tc); |
| 102 | tc->start_time = now; |
| 103 | tc->last_counted_time = now; |
| 104 | osmo_time_cc_update_from_tdef(tc, now); |
| 105 | osmo_time_cc_schedule_timer(tc, now); |
| 106 | } |
| 107 | |
| 108 | static void osmo_time_cc_count_time(struct osmo_time_cc *tc, uint64_t now) |
| 109 | { |
| 110 | uint64_t time_delta = now - tc->last_counted_time; |
| 111 | tc->last_counted_time = now; |
| 112 | if (!tc->flag_state) |
| 113 | return; |
| 114 | /* Flag is currently true, cumulate the elapsed time */ |
| 115 | tc->total_sum += time_delta; |
| 116 | tc->sum += time_delta; |
| 117 | } |
| 118 | |
| 119 | static void osmo_time_cc_report(struct osmo_time_cc *tc, uint64_t now) |
| 120 | { |
| 121 | uint64_t delta; |
| 122 | uint64_t n; |
Neels Hofmeyr | 25c9741 | 2021-11-13 23:19:33 +0100 | [diff] [blame] | 123 | /* We report a sum "rounded up", ahead of time. If the granularity period has not yet elapsed after the last |
| 124 | * reporting, do not report again yet. */ |
| 125 | if (tc->reported_sum > tc->sum) |
| 126 | return; |
| 127 | delta = tc->sum - tc->reported_sum; |
| 128 | /* elapsed full periods */ |
| 129 | n = delta / GRAN_USEC(tc); |
| 130 | /* If the delta has passed round_threshold (normally half of gran_usec), increment. */ |
| 131 | delta -= n * GRAN_USEC(tc); |
| 132 | if (delta >= ROUND_THRESHOLD_USEC(tc)) |
| 133 | n++; |
| 134 | if (!n) |
| 135 | return; |
| 136 | |
| 137 | /* integer sanity, since rate_ctr_add() takes an int argument. */ |
| 138 | if (n > INT_MAX) |
| 139 | n = INT_MAX; |
Neels Hofmeyr | b54229d | 2022-03-08 23:41:23 +0100 | [diff] [blame] | 140 | if (tc->cfg.rate_ctr) |
| 141 | rate_ctr_add(tc->cfg.rate_ctr, n); |
Neels Hofmeyr | 25c9741 | 2021-11-13 23:19:33 +0100 | [diff] [blame] | 142 | /* Store the increments of gran_usec that were counted. */ |
| 143 | tc->reported_sum += n * GRAN_USEC(tc); |
| 144 | } |
| 145 | |
| 146 | static void osmo_time_cc_forget_sum(struct osmo_time_cc *tc, uint64_t now) |
| 147 | { |
| 148 | tc->reported_sum = 0; |
| 149 | tc->sum = 0; |
| 150 | |
| 151 | if (tc->last_counted_time < now) |
| 152 | tc->last_counted_time = now; |
| 153 | } |
| 154 | |
| 155 | /*! Initialize struct osmo_time_cc. Call this once before use, and before setting up the .cfg items. */ |
| 156 | void osmo_time_cc_init(struct osmo_time_cc *tc) |
| 157 | { |
| 158 | *tc = (struct osmo_time_cc){0}; |
| 159 | } |
| 160 | |
| 161 | /*! Report state to be recorded by osmo_time_cc instance. Setting an unchanged state repeatedly has no effect. */ |
| 162 | void osmo_time_cc_set_flag(struct osmo_time_cc *tc, bool flag) |
| 163 | { |
| 164 | uint64_t now = time_now_usec(); |
| 165 | if (!tc->start_time) |
| 166 | osmo_time_cc_start(tc, now); |
| 167 | /* No flag change == no effect */ |
| 168 | if (flag == tc->flag_state) |
| 169 | return; |
| 170 | /* Sum up elapsed time, report increments for that. */ |
| 171 | osmo_time_cc_count_time(tc, now); |
| 172 | osmo_time_cc_report(tc, now); |
| 173 | tc->flag_state = flag; |
| 174 | osmo_time_cc_schedule_timer(tc, now); |
| 175 | } |
| 176 | |
| 177 | static void osmo_time_cc_timer_cb(void *data) |
| 178 | { |
| 179 | struct osmo_time_cc *tc = data; |
| 180 | uint64_t now = time_now_usec(); |
| 181 | |
| 182 | osmo_time_cc_update_from_tdef(tc, now); |
| 183 | |
| 184 | if (tc->flag_state) { |
| 185 | osmo_time_cc_count_time(tc, now); |
| 186 | osmo_time_cc_report(tc, now); |
| 187 | } else if (tc->cfg.forget_sum_usec && tc->sum |
| 188 | && (now >= tc->last_counted_time + tc->cfg.forget_sum_usec)) { |
| 189 | osmo_time_cc_forget_sum(tc, now); |
| 190 | } |
| 191 | osmo_time_cc_schedule_timer(tc, now); |
| 192 | } |
| 193 | |
| 194 | /*! Figure out the next time we should do anything, if the flag state remains unchanged. */ |
| 195 | static void osmo_time_cc_schedule_timer(struct osmo_time_cc *tc, uint64_t now) |
| 196 | { |
| 197 | uint64_t next_event = UINT64_MAX; |
| 198 | |
| 199 | osmo_time_cc_update_from_tdef(tc, now); |
| 200 | |
| 201 | /* If it is required, when will the next forget_sum happen? */ |
| 202 | if (tc->cfg.forget_sum_usec && !tc->flag_state && tc->sum > 0) { |
| 203 | uint64_t next_forget_time = tc->last_counted_time + tc->cfg.forget_sum_usec; |
| 204 | next_event = OSMO_MIN(next_event, next_forget_time); |
| 205 | } |
| 206 | /* Next rate_ctr increment? */ |
Neels Hofmeyr | b54229d | 2022-03-08 23:41:23 +0100 | [diff] [blame] | 207 | if (tc->flag_state) { |
Neels Hofmeyr | 25c9741 | 2021-11-13 23:19:33 +0100 | [diff] [blame] | 208 | uint64_t next_inc = now + (tc->reported_sum - tc->sum) + ROUND_THRESHOLD_USEC(tc); |
| 209 | next_event = OSMO_MIN(next_event, next_inc); |
| 210 | } |
| 211 | |
| 212 | /* No event coming up? */ |
| 213 | if (next_event == UINT64_MAX) |
| 214 | return; |
| 215 | |
| 216 | if (next_event <= now) |
| 217 | next_event = 0; |
| 218 | else |
| 219 | next_event -= now; |
| 220 | |
| 221 | osmo_timer_setup(&tc->timer, osmo_time_cc_timer_cb, tc); |
| 222 | osmo_timer_del(&tc->timer); |
| 223 | osmo_timer_schedule(&tc->timer, next_event / 1000000, next_event % 1000000); |
| 224 | } |
| 225 | |
| 226 | #endif /* HAVE_CLOCK_GETTIME */ |
| 227 | |
| 228 | /*! @} */ |