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