2 * Copyright (c) 2009, 2010, 2011, 2012, 2013, 2014 Nicira, Inc.
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"
27 #include "openvswitch/vlog.h"
29 VLOG_DEFINE_THIS_MODULE(coverage
);
31 /* The coverage counters. */
32 static struct coverage_counter
**coverage_counters
= NULL
;
33 static size_t n_coverage_counters
= 0;
34 static size_t allocated_coverage_counters
= 0;
36 static struct ovs_mutex coverage_mutex
= OVS_MUTEX_INITIALIZER
;
38 DEFINE_STATIC_PER_THREAD_DATA(long long int, coverage_clear_time
, LLONG_MIN
);
39 static long long int coverage_run_time
= LLONG_MIN
;
41 /* Index counter used to compute the moving average array's index. */
42 static unsigned int idx_count
= 0;
44 static void coverage_read(struct svec
*);
45 static unsigned int coverage_array_sum(const unsigned int *arr
,
46 const unsigned int len
);
48 /* Registers a coverage counter with the coverage core */
50 coverage_counter_register(struct coverage_counter
* counter
)
52 if (n_coverage_counters
>= allocated_coverage_counters
) {
53 coverage_counters
= x2nrealloc(coverage_counters
,
54 &allocated_coverage_counters
,
55 sizeof(struct coverage_counter
*));
57 coverage_counters
[n_coverage_counters
++] = counter
;
61 coverage_unixctl_show(struct unixctl_conn
*conn
, int argc OVS_UNUSED
,
62 const char *argv
[] OVS_UNUSED
, void *aux OVS_UNUSED
)
68 coverage_read(&lines
);
69 reply
= svec_join(&lines
, "\n", "\n");
70 unixctl_command_reply(conn
, reply
);
78 unixctl_command_register("coverage/show", "", 0, 0,
79 coverage_unixctl_show
, NULL
);
82 /* Sorts coverage counters in descending order by total, within equal
83 * totals alphabetically by name. */
85 compare_coverage_counters(const void *a_
, const void *b_
)
87 const struct coverage_counter
*const *ap
= a_
;
88 const struct coverage_counter
*const *bp
= b_
;
89 const struct coverage_counter
*a
= *ap
;
90 const struct coverage_counter
*b
= *bp
;
91 if (a
->total
!= b
->total
) {
92 return a
->total
< b
->total
? 1 : -1;
94 return strcmp(a
->name
, b
->name
);
101 struct coverage_counter
**c
;
105 /* Sort coverage counters into groups with equal totals. */
106 c
= xmalloc(n_coverage_counters
* sizeof *c
);
107 ovs_mutex_lock(&coverage_mutex
);
108 for (i
= 0; i
< n_coverage_counters
; i
++) {
109 c
[i
] = coverage_counters
[i
];
111 ovs_mutex_unlock(&coverage_mutex
);
112 qsort(c
, n_coverage_counters
, sizeof *c
, compare_coverage_counters
);
114 /* Hash the names in each group along with the rank. */
116 for (i
= 0; i
< n_coverage_counters
; ) {
123 hash
= hash_int(i
, hash
);
124 for (j
= i
; j
< n_coverage_counters
; j
++) {
125 if (c
[j
]->total
!= c
[i
]->total
) {
128 hash
= hash_string(c
[j
]->name
, hash
);
135 return hash_int(n_groups
, hash
);
139 coverage_hit(uint32_t hash
)
141 enum { HIT_BITS
= 1024, BITS_PER_WORD
= 32 };
142 static uint32_t hit
[HIT_BITS
/ BITS_PER_WORD
];
143 BUILD_ASSERT_DECL(IS_POW2(HIT_BITS
));
145 static long long int next_clear
= LLONG_MIN
;
147 unsigned int bit_index
= hash
& (HIT_BITS
- 1);
148 unsigned int word_index
= bit_index
/ BITS_PER_WORD
;
149 unsigned int word_mask
= 1u << (bit_index
% BITS_PER_WORD
);
151 /* Expire coverage hash suppression once a day. */
152 if (time_msec() >= next_clear
) {
153 memset(hit
, 0, sizeof hit
);
154 next_clear
= time_msec() + 60 * 60 * 24 * 1000LL;
157 if (hit
[word_index
] & word_mask
) {
160 hit
[word_index
] |= word_mask
;
165 /* Logs the coverage counters, unless a similar set of events has already been
168 * This function logs at log level VLL_INFO. Use care before adjusting this
169 * level, because depending on its configuration, syslogd can write changes
170 * synchronously, which can cause the coverage messages to take several seconds
175 static struct vlog_rate_limit rl
= VLOG_RATE_LIMIT_INIT(1, 3);
177 if (!VLOG_DROP_INFO(&rl
)) {
178 uint32_t hash
= coverage_hash();
179 if (coverage_hit(hash
)) {
180 VLOG_INFO("Skipping details of duplicate event coverage for "
181 "hash=%08"PRIx32
, hash
);
188 coverage_read(&lines
);
189 SVEC_FOR_EACH (i
, line
, &lines
) {
190 VLOG_INFO("%s", line
);
192 svec_destroy(&lines
);
197 /* Adds coverage counter information to 'lines'. */
199 coverage_read(struct svec
*lines
)
201 struct coverage_counter
**c
= coverage_counters
;
202 unsigned long long int *totals
;
207 hash
= coverage_hash();
210 svec_add_nocopy(lines
,
211 xasprintf("Event coverage, avg rate over last: %d "
212 "seconds, last minute, last hour, "
214 COVERAGE_RUN_INTERVAL
/1000, hash
));
216 totals
= xmalloc(n_coverage_counters
* sizeof *totals
);
217 ovs_mutex_lock(&coverage_mutex
);
218 for (i
= 0; i
< n_coverage_counters
; i
++) {
219 totals
[i
] = c
[i
]->total
;
221 ovs_mutex_unlock(&coverage_mutex
);
223 for (i
= 0; i
< n_coverage_counters
; i
++) {
225 /* Shows the averaged per-second rates for the last
226 * COVERAGE_RUN_INTERVAL interval, the last minute and
228 svec_add_nocopy(lines
,
229 xasprintf("%-24s %5.1f/sec %9.3f/sec "
230 "%13.4f/sec total: %llu",
232 (c
[i
]->min
[(idx_count
- 1) % MIN_AVG_LEN
]
233 * 1000.0 / COVERAGE_RUN_INTERVAL
),
234 coverage_array_sum(c
[i
]->min
, MIN_AVG_LEN
) / 60.0,
235 coverage_array_sum(c
[i
]->hr
, HR_AVG_LEN
) / 3600.0,
242 svec_add_nocopy(lines
, xasprintf("%"PRIuSIZE
" events never hit", n_never_hit
));
246 /* Runs approximately every COVERAGE_CLEAR_INTERVAL amount of time to
247 * synchronize per-thread counters with global counters. Every thread maintains
248 * a separate timer to ensure all counters are periodically aggregated. */
252 long long int now
, *thread_time
;
255 thread_time
= coverage_clear_time_get();
257 /* Initialize the coverage_clear_time. */
258 if (*thread_time
== LLONG_MIN
) {
259 *thread_time
= now
+ COVERAGE_CLEAR_INTERVAL
;
262 if (now
>= *thread_time
) {
265 ovs_mutex_lock(&coverage_mutex
);
266 for (i
= 0; i
< n_coverage_counters
; i
++) {
267 struct coverage_counter
*c
= coverage_counters
[i
];
268 c
->total
+= c
->count();
270 ovs_mutex_unlock(&coverage_mutex
);
271 *thread_time
= now
+ COVERAGE_CLEAR_INTERVAL
;
275 /* Runs approximately every COVERAGE_RUN_INTERVAL amount of time to update the
276 * coverage counters' 'min' and 'hr' array. 'min' array is for cumulating
277 * per second counts into per minute count. 'hr' array is for cumulating per
278 * minute counts into per hour count. Every thread may call this function. */
282 struct coverage_counter
**c
= coverage_counters
;
285 ovs_mutex_lock(&coverage_mutex
);
287 /* Initialize the coverage_run_time. */
288 if (coverage_run_time
== LLONG_MIN
) {
289 coverage_run_time
= now
+ COVERAGE_RUN_INTERVAL
;
292 if (now
>= coverage_run_time
) {
294 /* Computes the number of COVERAGE_RUN_INTERVAL slots, since
295 * it is possible that the actual run interval is multiple of
296 * COVERAGE_RUN_INTERVAL. */
297 int slots
= (now
- coverage_run_time
) / COVERAGE_RUN_INTERVAL
+ 1;
299 for (i
= 0; i
< n_coverage_counters
; i
++) {
300 unsigned int count
, portion
;
301 unsigned int idx
= idx_count
;
303 /* Computes the differences between the current total and the one
304 * recorded in last invocation of coverage_run(). */
305 count
= c
[i
]->total
- c
[i
]->last_total
;
306 c
[i
]->last_total
= c
[i
]->total
;
307 /* The count over the time interval is evenly distributed
308 * among slots by calculating the portion. */
309 portion
= count
/ slots
;
311 for (j
= 0; j
< slots
; j
++) {
312 /* Updates the index variables. */
313 /* The m_idx is increased from 0 to MIN_AVG_LEN - 1. Every
314 * time the m_idx finishes a cycle (a cycle is one minute),
315 * the h_idx is incremented by 1. */
316 unsigned int m_idx
= idx
% MIN_AVG_LEN
;
317 unsigned int h_idx
= idx
/ MIN_AVG_LEN
;
319 c
[i
]->min
[m_idx
] = portion
+ (j
== (slots
- 1)
320 ? count
% slots
: 0);
321 c
[i
]->hr
[h_idx
] = m_idx
== 0
323 : (c
[i
]->hr
[h_idx
] + c
[i
]->min
[m_idx
]);
324 /* This is to guarantee that h_idx ranges from 0 to 59. */
325 idx
= (idx
+ 1) % (MIN_AVG_LEN
* HR_AVG_LEN
);
329 /* Updates the global index variables. */
330 idx_count
= (idx_count
+ slots
) % (MIN_AVG_LEN
* HR_AVG_LEN
);
331 /* Updates the run time. */
332 coverage_run_time
= now
+ COVERAGE_RUN_INTERVAL
;
334 ovs_mutex_unlock(&coverage_mutex
);
338 coverage_array_sum(const unsigned int *arr
, const unsigned int len
)
340 unsigned int sum
= 0;
343 ovs_mutex_lock(&coverage_mutex
);
344 for (i
= 0; i
< len
; i
++) {
347 ovs_mutex_unlock(&coverage_mutex
);