stats.c revision 1.1.2.2
1 /* $NetBSD: stats.c,v 1.1.2.2 2024/02/24 13:07:21 martin Exp $ */ 2 3 /* 4 * Copyright (C) Internet Systems Consortium, Inc. ("ISC") 5 * 6 * SPDX-License-Identifier: MPL-2.0 7 * 8 * This Source Code Form is subject to the terms of the Mozilla Public 9 * License, v. 2.0. If a copy of the MPL was not distributed with this 10 * file, you can obtain one at https://mozilla.org/MPL/2.0/. 11 * 12 * See the COPYRIGHT file distributed with this work for additional 13 * information regarding copyright ownership. 14 */ 15 16 /*! \file */ 17 18 #include <inttypes.h> 19 #include <string.h> 20 21 #include <isc/atomic.h> 22 #include <isc/buffer.h> 23 #include <isc/magic.h> 24 #include <isc/mem.h> 25 #include <isc/platform.h> 26 #include <isc/print.h> 27 #include <isc/refcount.h> 28 #include <isc/stats.h> 29 #include <isc/util.h> 30 31 #define ISC_STATS_MAGIC ISC_MAGIC('S', 't', 'a', 't') 32 #define ISC_STATS_VALID(x) ISC_MAGIC_VALID(x, ISC_STATS_MAGIC) 33 34 #if (defined(_WIN32) && !defined(_WIN64)) || !defined(_LP64) 35 typedef atomic_int_fast32_t isc__atomic_statcounter_t; 36 #else /* if defined(_WIN32) && !defined(_WIN64) */ 37 typedef atomic_int_fast64_t isc__atomic_statcounter_t; 38 #endif /* if defined(_WIN32) && !defined(_WIN64) */ 39 40 struct isc_stats { 41 unsigned int magic; 42 isc_mem_t *mctx; 43 isc_refcount_t references; 44 int ncounters; 45 isc__atomic_statcounter_t *counters; 46 }; 47 48 static isc_result_t 49 create_stats(isc_mem_t *mctx, int ncounters, isc_stats_t **statsp) { 50 isc_stats_t *stats; 51 size_t counters_alloc_size; 52 53 REQUIRE(statsp != NULL && *statsp == NULL); 54 55 stats = isc_mem_get(mctx, sizeof(*stats)); 56 counters_alloc_size = sizeof(isc__atomic_statcounter_t) * ncounters; 57 stats->counters = isc_mem_get(mctx, counters_alloc_size); 58 isc_refcount_init(&stats->references, 1); 59 for (int i = 0; i < ncounters; i++) { 60 atomic_init(&stats->counters[i], 0); 61 } 62 stats->mctx = NULL; 63 isc_mem_attach(mctx, &stats->mctx); 64 stats->ncounters = ncounters; 65 stats->magic = ISC_STATS_MAGIC; 66 *statsp = stats; 67 68 return (ISC_R_SUCCESS); 69 } 70 71 void 72 isc_stats_attach(isc_stats_t *stats, isc_stats_t **statsp) { 73 REQUIRE(ISC_STATS_VALID(stats)); 74 REQUIRE(statsp != NULL && *statsp == NULL); 75 76 isc_refcount_increment(&stats->references); 77 *statsp = stats; 78 } 79 80 void 81 isc_stats_detach(isc_stats_t **statsp) { 82 isc_stats_t *stats; 83 84 REQUIRE(statsp != NULL && ISC_STATS_VALID(*statsp)); 85 86 stats = *statsp; 87 *statsp = NULL; 88 89 if (isc_refcount_decrement(&stats->references) == 1) { 90 isc_refcount_destroy(&stats->references); 91 isc_mem_put(stats->mctx, stats->counters, 92 sizeof(isc__atomic_statcounter_t) * 93 stats->ncounters); 94 isc_mem_putanddetach(&stats->mctx, stats, sizeof(*stats)); 95 } 96 } 97 98 int 99 isc_stats_ncounters(isc_stats_t *stats) { 100 REQUIRE(ISC_STATS_VALID(stats)); 101 102 return (stats->ncounters); 103 } 104 105 isc_result_t 106 isc_stats_create(isc_mem_t *mctx, isc_stats_t **statsp, int ncounters) { 107 REQUIRE(statsp != NULL && *statsp == NULL); 108 109 return (create_stats(mctx, ncounters, statsp)); 110 } 111 112 void 113 isc_stats_increment(isc_stats_t *stats, isc_statscounter_t counter) { 114 REQUIRE(ISC_STATS_VALID(stats)); 115 REQUIRE(counter < stats->ncounters); 116 117 atomic_fetch_add_relaxed(&stats->counters[counter], 1); 118 } 119 120 void 121 isc_stats_decrement(isc_stats_t *stats, isc_statscounter_t counter) { 122 REQUIRE(ISC_STATS_VALID(stats)); 123 REQUIRE(counter < stats->ncounters); 124 atomic_fetch_sub_release(&stats->counters[counter], 1); 125 } 126 127 void 128 isc_stats_dump(isc_stats_t *stats, isc_stats_dumper_t dump_fn, void *arg, 129 unsigned int options) { 130 int i; 131 132 REQUIRE(ISC_STATS_VALID(stats)); 133 134 for (i = 0; i < stats->ncounters; i++) { 135 uint32_t counter = atomic_load_acquire(&stats->counters[i]); 136 if ((options & ISC_STATSDUMP_VERBOSE) == 0 && counter == 0) { 137 continue; 138 } 139 dump_fn((isc_statscounter_t)i, counter, arg); 140 } 141 } 142 143 void 144 isc_stats_set(isc_stats_t *stats, uint64_t val, isc_statscounter_t counter) { 145 REQUIRE(ISC_STATS_VALID(stats)); 146 REQUIRE(counter < stats->ncounters); 147 148 atomic_store_release(&stats->counters[counter], val); 149 } 150 151 void 152 isc_stats_update_if_greater(isc_stats_t *stats, isc_statscounter_t counter, 153 isc_statscounter_t value) { 154 REQUIRE(ISC_STATS_VALID(stats)); 155 REQUIRE(counter < stats->ncounters); 156 157 isc_statscounter_t curr_value = 158 atomic_load_acquire(&stats->counters[counter]); 159 do { 160 if (curr_value >= value) { 161 break; 162 } 163 } while (!atomic_compare_exchange_weak_acq_rel( 164 &stats->counters[counter], &curr_value, value)); 165 } 166 167 isc_statscounter_t 168 isc_stats_get_counter(isc_stats_t *stats, isc_statscounter_t counter) { 169 REQUIRE(ISC_STATS_VALID(stats)); 170 REQUIRE(counter < stats->ncounters); 171 172 return (atomic_load_acquire(&stats->counters[counter])); 173 } 174 175 void 176 isc_stats_resize(isc_stats_t **statsp, int ncounters) { 177 isc_stats_t *stats; 178 size_t counters_alloc_size; 179 isc__atomic_statcounter_t *newcounters; 180 181 REQUIRE(statsp != NULL && *statsp != NULL); 182 REQUIRE(ISC_STATS_VALID(*statsp)); 183 REQUIRE(ncounters > 0); 184 185 stats = *statsp; 186 if (stats->ncounters >= ncounters) { 187 /* We already have enough counters. */ 188 return; 189 } 190 191 /* Grow number of counters. */ 192 counters_alloc_size = sizeof(isc__atomic_statcounter_t) * ncounters; 193 newcounters = isc_mem_get(stats->mctx, counters_alloc_size); 194 for (int i = 0; i < ncounters; i++) { 195 atomic_init(&newcounters[i], 0); 196 } 197 for (int i = 0; i < stats->ncounters; i++) { 198 uint32_t counter = atomic_load_acquire(&stats->counters[i]); 199 atomic_store_release(&newcounters[i], counter); 200 } 201 isc_mem_put(stats->mctx, stats->counters, 202 sizeof(isc__atomic_statcounter_t) * stats->ncounters); 203 stats->counters = newcounters; 204 stats->ncounters = ncounters; 205 } 206
Indexes created Mon May 04 00:23:20 UTC 2026