2 * Copyright (c) 2009, 2010, 2011, 2012 Nicira Networks.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
21 #include "dynamic-string.h"
28 VLOG_DEFINE_THIS_MODULE(coverage);
30 /* The coverage counters. */
31 #if USE_LINKER_SECTIONS
32 extern struct coverage_counter *__start_coverage[];
33 extern struct coverage_counter *__stop_coverage[];
34 #define coverage_counters __start_coverage
35 #define n_coverage_counters (__stop_coverage - __start_coverage)
36 #else /* !USE_LINKER_SECTIONS */
37 #define COVERAGE_COUNTER(NAME) COVERAGE_DEFINE__(NAME);
38 #include "coverage.def"
39 #undef COVERAGE_COUNTER
41 struct coverage_counter *coverage_counters[] = {
42 #define COVERAGE_COUNTER(NAME) &counter_##NAME,
43 #include "coverage.def"
44 #undef COVERAGE_COUNTER
46 #define n_coverage_counters ARRAY_SIZE(coverage_counters)
47 #endif /* !USE_LINKER_SECTIONS */
49 static unsigned int epoch;
52 coverage_unixctl_log(struct unixctl_conn *conn, int argc OVS_UNUSED,
53 const char *argv[] OVS_UNUSED, void *aux OVS_UNUSED)
55 coverage_log(VLL_WARN, false);
56 unixctl_command_reply(conn, NULL);
62 unixctl_command_register("coverage/log", "", 0, 0,
63 coverage_unixctl_log, NULL);
66 /* Sorts coverage counters in descending order by count, within equal counts
67 * alphabetically by name. */
69 compare_coverage_counters(const void *a_, const void *b_)
71 const struct coverage_counter *const *ap = a_;
72 const struct coverage_counter *const *bp = b_;
73 const struct coverage_counter *a = *ap;
74 const struct coverage_counter *b = *bp;
75 if (a->count != b->count) {
76 return a->count < b->count ? 1 : -1;
78 return strcmp(a->name, b->name);
85 struct coverage_counter **c;
89 /* Sort coverage counters into groups with equal counts. */
90 c = xmalloc(n_coverage_counters * sizeof *c);
91 for (i = 0; i < n_coverage_counters; i++) {
92 c[i] = coverage_counters[i];
94 qsort(c, n_coverage_counters, sizeof *c, compare_coverage_counters);
96 /* Hash the names in each group along with the rank. */
98 for (i = 0; i < n_coverage_counters; ) {
105 hash = hash_int(i, hash);
106 for (j = i; j < n_coverage_counters; j++) {
107 if (c[j]->count != c[i]->count) {
110 hash = hash_string(c[j]->name, hash);
117 return hash_int(n_groups, hash);
121 coverage_hit(uint32_t hash)
123 enum { HIT_BITS = 1024, BITS_PER_WORD = 32 };
124 static uint32_t hit[HIT_BITS / BITS_PER_WORD];
125 BUILD_ASSERT_DECL(IS_POW2(HIT_BITS));
127 static long long int next_clear = LLONG_MIN;
129 unsigned int bit_index = hash & (HIT_BITS - 1);
130 unsigned int word_index = bit_index / BITS_PER_WORD;
131 unsigned int word_mask = 1u << (bit_index % BITS_PER_WORD);
133 /* Expire coverage hash suppression once a day. */
134 if (time_msec() >= next_clear) {
135 memset(hit, 0, sizeof hit);
136 next_clear = time_msec() + 60 * 60 * 24 * 1000LL;
139 if (hit[word_index] & word_mask) {
142 hit[word_index] |= word_mask;
148 coverage_log_counter(enum vlog_level level, const struct coverage_counter *c)
150 VLOG(level, "%-24s %5u / %9llu", c->name, c->count, c->count + c->total);
153 /* Logs the coverage counters at the given vlog 'level'. If
154 * 'suppress_dups' is true, then duplicate events are not displayed.
155 * Care should be taken in the value used for 'level'. Depending on the
156 * configuration, syslog can write changes synchronously, which can
157 * cause the coverage messages to take several seconds to write. */
159 coverage_log(enum vlog_level level, bool suppress_dups)
165 if (!vlog_is_enabled(THIS_MODULE, level)) {
169 hash = coverage_hash();
171 if (coverage_hit(hash)) {
172 VLOG(level, "Skipping details of duplicate event coverage for "
173 "hash=%08"PRIx32" in epoch %u", hash, epoch);
179 VLOG(level, "Event coverage (epoch %u/entire run), hash=%08"PRIx32":",
181 for (i = 0; i < n_coverage_counters; i++) {
182 struct coverage_counter *c = coverage_counters[i];
184 coverage_log_counter(level, c);
187 for (i = 0; i < n_coverage_counters; i++) {
188 struct coverage_counter *c = coverage_counters[i];
191 coverage_log_counter(level, c);
197 VLOG(level, "%zu events never hit", n_never_hit);
200 /* Advances to the next epoch of coverage, resetting all the counters to 0. */
207 for (i = 0; i < n_coverage_counters; i++) {
208 struct coverage_counter *c = coverage_counters[i];
209 c->total += c->count;