Commit | Line | Data |
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331744e3 JD |
1 | /* |
2 | * Copyright (C) 2012 - Julien Desfossez <julien.desfossez@efficios.com> | |
3 | * David Goulet <dgoulet@efficios.com> | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or modify it | |
6 | * under the terms of the GNU General Public License, version 2 only, as | |
7 | * published by the Free Software Foundation. | |
8 | * | |
9 | * This program is distributed in the hope that it will be useful, but WITHOUT | |
10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
12 | * more details. | |
13 | * | |
14 | * You should have received a copy of the GNU General Public License along with | |
15 | * this program; if not, write to the Free Software Foundation, Inc., 51 | |
16 | * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. | |
17 | */ | |
18 | ||
19 | #define _GNU_SOURCE | |
20 | #include <assert.h> | |
21 | #include <inttypes.h> | |
22 | #include <signal.h> | |
23 | ||
51a9e1c7 | 24 | #include <bin/lttng-consumerd/health-consumerd.h> |
331744e3 | 25 | #include <common/common.h> |
d3e2ba59 JD |
26 | #include <common/kernel-ctl/kernel-ctl.h> |
27 | #include <common/kernel-consumer/kernel-consumer.h> | |
28 | #include <common/consumer-stream.h> | |
331744e3 JD |
29 | |
30 | #include "consumer-timer.h" | |
2d57de81 | 31 | #include "consumer-testpoint.h" |
331744e3 JD |
32 | #include "ust-consumer/ust-consumer.h" |
33 | ||
2b8f8754 MD |
34 | static struct timer_signal_data timer_signal = { |
35 | .tid = 0, | |
36 | .setup_done = 0, | |
37 | .qs_done = 0, | |
38 | .lock = PTHREAD_MUTEX_INITIALIZER, | |
39 | }; | |
331744e3 JD |
40 | |
41 | /* | |
42 | * Set custom signal mask to current thread. | |
43 | */ | |
44 | static void setmask(sigset_t *mask) | |
45 | { | |
46 | int ret; | |
47 | ||
48 | ret = sigemptyset(mask); | |
49 | if (ret) { | |
50 | PERROR("sigemptyset"); | |
51 | } | |
52 | ret = sigaddset(mask, LTTNG_CONSUMER_SIG_SWITCH); | |
53 | if (ret) { | |
d3e2ba59 | 54 | PERROR("sigaddset switch"); |
331744e3 JD |
55 | } |
56 | ret = sigaddset(mask, LTTNG_CONSUMER_SIG_TEARDOWN); | |
57 | if (ret) { | |
d3e2ba59 JD |
58 | PERROR("sigaddset teardown"); |
59 | } | |
60 | ret = sigaddset(mask, LTTNG_CONSUMER_SIG_LIVE); | |
61 | if (ret) { | |
62 | PERROR("sigaddset live"); | |
331744e3 JD |
63 | } |
64 | } | |
65 | ||
66 | /* | |
67 | * Execute action on a timer switch. | |
d98a47c7 MD |
68 | * |
69 | * Beware: metadata_switch_timer() should *never* take a mutex also held | |
70 | * while consumer_timer_switch_stop() is called. It would result in | |
71 | * deadlocks. | |
331744e3 JD |
72 | */ |
73 | static void metadata_switch_timer(struct lttng_consumer_local_data *ctx, | |
74 | int sig, siginfo_t *si, void *uc) | |
75 | { | |
76 | int ret; | |
77 | struct lttng_consumer_channel *channel; | |
78 | ||
79 | channel = si->si_value.sival_ptr; | |
80 | assert(channel); | |
81 | ||
4419b4fb MD |
82 | if (channel->switch_timer_error) { |
83 | return; | |
84 | } | |
85 | ||
331744e3 JD |
86 | DBG("Switch timer for channel %" PRIu64, channel->key); |
87 | switch (ctx->type) { | |
88 | case LTTNG_CONSUMER32_UST: | |
89 | case LTTNG_CONSUMER64_UST: | |
4fa3dc0e MD |
90 | /* |
91 | * Locks taken by lttng_ustconsumer_request_metadata(): | |
92 | * - metadata_socket_lock | |
93 | * - Calling lttng_ustconsumer_recv_metadata(): | |
f82d9449 | 94 | * - channel->metadata_cache->lock |
4fa3dc0e | 95 | * - Calling consumer_metadata_cache_flushed(): |
5e41ebe1 MD |
96 | * - channel->timer_lock |
97 | * - channel->metadata_cache->lock | |
4fa3dc0e | 98 | * |
5e41ebe1 MD |
99 | * Ensure that neither consumer_data.lock nor |
100 | * channel->lock are taken within this function, since | |
101 | * they are held while consumer_timer_switch_stop() is | |
102 | * called. | |
4fa3dc0e | 103 | */ |
94d49140 | 104 | ret = lttng_ustconsumer_request_metadata(ctx, channel, 1, 1); |
331744e3 | 105 | if (ret < 0) { |
4419b4fb | 106 | channel->switch_timer_error = 1; |
331744e3 JD |
107 | } |
108 | break; | |
109 | case LTTNG_CONSUMER_KERNEL: | |
110 | case LTTNG_CONSUMER_UNKNOWN: | |
111 | assert(0); | |
112 | break; | |
113 | } | |
114 | } | |
115 | ||
d3e2ba59 JD |
116 | static int send_empty_index(struct lttng_consumer_stream *stream, uint64_t ts) |
117 | { | |
118 | int ret; | |
50adc264 | 119 | struct ctf_packet_index index; |
d3e2ba59 JD |
120 | |
121 | memset(&index, 0, sizeof(index)); | |
122 | index.timestamp_end = htobe64(ts); | |
123 | ret = consumer_stream_write_index(stream, &index); | |
124 | if (ret < 0) { | |
125 | goto error; | |
126 | } | |
127 | ||
128 | error: | |
129 | return ret; | |
130 | } | |
131 | ||
132 | static int check_kernel_stream(struct lttng_consumer_stream *stream) | |
133 | { | |
134 | uint64_t ts; | |
135 | int ret; | |
136 | ||
137 | /* | |
138 | * While holding the stream mutex, try to take a snapshot, if it | |
139 | * succeeds, it means that data is ready to be sent, just let the data | |
140 | * thread handle that. Otherwise, if the snapshot returns EAGAIN, it | |
141 | * means that there is no data to read after the flush, so we can | |
142 | * safely send the empty index. | |
143 | */ | |
144 | pthread_mutex_lock(&stream->lock); | |
145 | ret = kernctl_get_current_timestamp(stream->wait_fd, &ts); | |
146 | if (ret < 0) { | |
147 | ERR("Failed to get the current timestamp"); | |
148 | goto error_unlock; | |
149 | } | |
150 | ret = kernctl_buffer_flush(stream->wait_fd); | |
151 | if (ret < 0) { | |
152 | ERR("Failed to flush kernel stream"); | |
153 | goto error_unlock; | |
154 | } | |
155 | ret = kernctl_snapshot(stream->wait_fd); | |
156 | if (ret < 0) { | |
157 | if (errno != EAGAIN) { | |
158 | ERR("Taking kernel snapshot"); | |
159 | ret = -1; | |
160 | goto error_unlock; | |
161 | } | |
162 | DBG("Stream %" PRIu64 " empty, sending beacon", stream->key); | |
163 | ret = send_empty_index(stream, ts); | |
164 | if (ret < 0) { | |
165 | goto error_unlock; | |
166 | } | |
167 | } | |
168 | ret = 0; | |
169 | ||
170 | error_unlock: | |
171 | pthread_mutex_unlock(&stream->lock); | |
172 | return ret; | |
173 | } | |
174 | ||
175 | static int check_ust_stream(struct lttng_consumer_stream *stream) | |
176 | { | |
177 | uint64_t ts; | |
178 | int ret; | |
179 | ||
180 | assert(stream); | |
181 | assert(stream->ustream); | |
182 | /* | |
183 | * While holding the stream mutex, try to take a snapshot, if it | |
184 | * succeeds, it means that data is ready to be sent, just let the data | |
185 | * thread handle that. Otherwise, if the snapshot returns EAGAIN, it | |
186 | * means that there is no data to read after the flush, so we can | |
187 | * safely send the empty index. | |
188 | */ | |
189 | pthread_mutex_lock(&stream->lock); | |
94d49140 JD |
190 | ret = cds_lfht_is_node_deleted(&stream->node.node); |
191 | if (ret) { | |
192 | goto error_unlock; | |
193 | } | |
194 | ||
84a182ce | 195 | ret = lttng_ustconsumer_get_current_timestamp(stream, &ts); |
d3e2ba59 JD |
196 | if (ret < 0) { |
197 | ERR("Failed to get the current timestamp"); | |
198 | goto error_unlock; | |
199 | } | |
84a182ce DG |
200 | lttng_ustconsumer_flush_buffer(stream, 1); |
201 | ret = lttng_ustconsumer_take_snapshot(stream); | |
d3e2ba59 | 202 | if (ret < 0) { |
94d49140 | 203 | if (ret != -EAGAIN) { |
d3e2ba59 JD |
204 | ERR("Taking UST snapshot"); |
205 | ret = -1; | |
206 | goto error_unlock; | |
207 | } | |
208 | DBG("Stream %" PRIu64 " empty, sending beacon", stream->key); | |
209 | ret = send_empty_index(stream, ts); | |
210 | if (ret < 0) { | |
211 | goto error_unlock; | |
212 | } | |
213 | } | |
214 | ret = 0; | |
215 | ||
216 | error_unlock: | |
217 | pthread_mutex_unlock(&stream->lock); | |
218 | return ret; | |
219 | } | |
220 | ||
221 | /* | |
222 | * Execute action on a live timer | |
223 | */ | |
224 | static void live_timer(struct lttng_consumer_local_data *ctx, | |
225 | int sig, siginfo_t *si, void *uc) | |
226 | { | |
227 | int ret; | |
228 | struct lttng_consumer_channel *channel; | |
229 | struct lttng_consumer_stream *stream; | |
230 | struct lttng_ht *ht; | |
231 | struct lttng_ht_iter iter; | |
232 | ||
233 | channel = si->si_value.sival_ptr; | |
234 | assert(channel); | |
235 | ||
236 | if (channel->switch_timer_error) { | |
237 | goto error; | |
238 | } | |
239 | ht = consumer_data.stream_per_chan_id_ht; | |
240 | ||
241 | DBG("Live timer for channel %" PRIu64, channel->key); | |
242 | ||
243 | rcu_read_lock(); | |
244 | switch (ctx->type) { | |
245 | case LTTNG_CONSUMER32_UST: | |
246 | case LTTNG_CONSUMER64_UST: | |
247 | cds_lfht_for_each_entry_duplicate(ht->ht, | |
248 | ht->hash_fct(&channel->key, lttng_ht_seed), | |
249 | ht->match_fct, &channel->key, &iter.iter, | |
250 | stream, node_channel_id.node) { | |
251 | ret = check_ust_stream(stream); | |
252 | if (ret < 0) { | |
253 | goto error_unlock; | |
254 | } | |
255 | } | |
256 | break; | |
257 | case LTTNG_CONSUMER_KERNEL: | |
258 | cds_lfht_for_each_entry_duplicate(ht->ht, | |
259 | ht->hash_fct(&channel->key, lttng_ht_seed), | |
260 | ht->match_fct, &channel->key, &iter.iter, | |
261 | stream, node_channel_id.node) { | |
262 | ret = check_kernel_stream(stream); | |
263 | if (ret < 0) { | |
264 | goto error_unlock; | |
265 | } | |
266 | } | |
267 | break; | |
268 | case LTTNG_CONSUMER_UNKNOWN: | |
269 | assert(0); | |
270 | break; | |
271 | } | |
272 | ||
273 | error_unlock: | |
274 | rcu_read_unlock(); | |
275 | ||
276 | error: | |
277 | return; | |
278 | } | |
279 | ||
2b8f8754 MD |
280 | static |
281 | void consumer_timer_signal_thread_qs(unsigned int signr) | |
282 | { | |
283 | sigset_t pending_set; | |
284 | int ret; | |
285 | ||
286 | /* | |
287 | * We need to be the only thread interacting with the thread | |
288 | * that manages signals for teardown synchronization. | |
289 | */ | |
290 | pthread_mutex_lock(&timer_signal.lock); | |
291 | ||
292 | /* Ensure we don't have any signal queued for this channel. */ | |
293 | for (;;) { | |
294 | ret = sigemptyset(&pending_set); | |
295 | if (ret == -1) { | |
296 | PERROR("sigemptyset"); | |
297 | } | |
298 | ret = sigpending(&pending_set); | |
299 | if (ret == -1) { | |
300 | PERROR("sigpending"); | |
301 | } | |
302 | if (!sigismember(&pending_set, LTTNG_CONSUMER_SIG_SWITCH)) { | |
303 | break; | |
304 | } | |
305 | caa_cpu_relax(); | |
306 | } | |
307 | ||
308 | /* | |
309 | * From this point, no new signal handler will be fired that would try to | |
310 | * access "chan". However, we still need to wait for any currently | |
311 | * executing handler to complete. | |
312 | */ | |
313 | cmm_smp_mb(); | |
314 | CMM_STORE_SHARED(timer_signal.qs_done, 0); | |
315 | cmm_smp_mb(); | |
316 | ||
317 | /* | |
318 | * Kill with LTTNG_CONSUMER_SIG_TEARDOWN, so signal management thread wakes | |
319 | * up. | |
320 | */ | |
321 | kill(getpid(), LTTNG_CONSUMER_SIG_TEARDOWN); | |
322 | ||
323 | while (!CMM_LOAD_SHARED(timer_signal.qs_done)) { | |
324 | caa_cpu_relax(); | |
325 | } | |
326 | cmm_smp_mb(); | |
327 | ||
328 | pthread_mutex_unlock(&timer_signal.lock); | |
329 | } | |
330 | ||
331744e3 JD |
331 | /* |
332 | * Set the timer for periodical metadata flush. | |
333 | */ | |
334 | void consumer_timer_switch_start(struct lttng_consumer_channel *channel, | |
335 | unsigned int switch_timer_interval) | |
336 | { | |
337 | int ret; | |
338 | struct sigevent sev; | |
339 | struct itimerspec its; | |
340 | ||
341 | assert(channel); | |
342 | assert(channel->key); | |
343 | ||
344 | if (switch_timer_interval == 0) { | |
345 | return; | |
346 | } | |
347 | ||
348 | sev.sigev_notify = SIGEV_SIGNAL; | |
349 | sev.sigev_signo = LTTNG_CONSUMER_SIG_SWITCH; | |
350 | sev.sigev_value.sival_ptr = channel; | |
351 | ret = timer_create(CLOCKID, &sev, &channel->switch_timer); | |
352 | if (ret == -1) { | |
353 | PERROR("timer_create"); | |
354 | } | |
355 | channel->switch_timer_enabled = 1; | |
356 | ||
357 | its.it_value.tv_sec = switch_timer_interval / 1000000; | |
358 | its.it_value.tv_nsec = switch_timer_interval % 1000000; | |
359 | its.it_interval.tv_sec = its.it_value.tv_sec; | |
360 | its.it_interval.tv_nsec = its.it_value.tv_nsec; | |
361 | ||
362 | ret = timer_settime(channel->switch_timer, 0, &its, NULL); | |
363 | if (ret == -1) { | |
364 | PERROR("timer_settime"); | |
365 | } | |
366 | } | |
367 | ||
368 | /* | |
369 | * Stop and delete timer. | |
370 | */ | |
371 | void consumer_timer_switch_stop(struct lttng_consumer_channel *channel) | |
372 | { | |
373 | int ret; | |
331744e3 JD |
374 | |
375 | assert(channel); | |
376 | ||
377 | ret = timer_delete(channel->switch_timer); | |
378 | if (ret == -1) { | |
379 | PERROR("timer_delete"); | |
380 | } | |
381 | ||
2b8f8754 | 382 | consumer_timer_signal_thread_qs(LTTNG_CONSUMER_SIG_SWITCH); |
331744e3 | 383 | |
2b8f8754 MD |
384 | channel->switch_timer = 0; |
385 | channel->switch_timer_enabled = 0; | |
331744e3 JD |
386 | } |
387 | ||
d3e2ba59 JD |
388 | /* |
389 | * Set the timer for the live mode. | |
390 | */ | |
391 | void consumer_timer_live_start(struct lttng_consumer_channel *channel, | |
392 | int live_timer_interval) | |
393 | { | |
394 | int ret; | |
395 | struct sigevent sev; | |
396 | struct itimerspec its; | |
397 | ||
398 | assert(channel); | |
399 | assert(channel->key); | |
400 | ||
fac41e72 | 401 | if (live_timer_interval <= 0) { |
d3e2ba59 JD |
402 | return; |
403 | } | |
404 | ||
405 | sev.sigev_notify = SIGEV_SIGNAL; | |
406 | sev.sigev_signo = LTTNG_CONSUMER_SIG_LIVE; | |
407 | sev.sigev_value.sival_ptr = channel; | |
408 | ret = timer_create(CLOCKID, &sev, &channel->live_timer); | |
409 | if (ret == -1) { | |
410 | PERROR("timer_create"); | |
411 | } | |
412 | channel->live_timer_enabled = 1; | |
413 | ||
414 | its.it_value.tv_sec = live_timer_interval / 1000000; | |
415 | its.it_value.tv_nsec = live_timer_interval % 1000000; | |
416 | its.it_interval.tv_sec = its.it_value.tv_sec; | |
417 | its.it_interval.tv_nsec = its.it_value.tv_nsec; | |
418 | ||
419 | ret = timer_settime(channel->live_timer, 0, &its, NULL); | |
420 | if (ret == -1) { | |
421 | PERROR("timer_settime"); | |
422 | } | |
423 | } | |
424 | ||
425 | /* | |
426 | * Stop and delete timer. | |
427 | */ | |
428 | void consumer_timer_live_stop(struct lttng_consumer_channel *channel) | |
429 | { | |
430 | int ret; | |
431 | ||
432 | assert(channel); | |
433 | ||
434 | ret = timer_delete(channel->live_timer); | |
435 | if (ret == -1) { | |
436 | PERROR("timer_delete"); | |
437 | } | |
438 | ||
439 | consumer_timer_signal_thread_qs(LTTNG_CONSUMER_SIG_LIVE); | |
440 | ||
441 | channel->live_timer = 0; | |
442 | channel->live_timer_enabled = 0; | |
443 | } | |
444 | ||
331744e3 JD |
445 | /* |
446 | * Block the RT signals for the entire process. It must be called from the | |
447 | * consumer main before creating the threads | |
448 | */ | |
449 | void consumer_signal_init(void) | |
450 | { | |
451 | int ret; | |
452 | sigset_t mask; | |
453 | ||
454 | /* Block signal for entire process, so only our thread processes it. */ | |
455 | setmask(&mask); | |
456 | ret = pthread_sigmask(SIG_BLOCK, &mask, NULL); | |
457 | if (ret) { | |
458 | errno = ret; | |
459 | PERROR("pthread_sigmask"); | |
460 | } | |
461 | } | |
462 | ||
463 | /* | |
d3e2ba59 JD |
464 | * This thread is the sighandler for signals LTTNG_CONSUMER_SIG_SWITCH, |
465 | * LTTNG_CONSUMER_SIG_TEARDOWN and LTTNG_CONSUMER_SIG_LIVE. | |
331744e3 | 466 | */ |
d3e2ba59 | 467 | void *consumer_timer_thread(void *data) |
331744e3 JD |
468 | { |
469 | int signr; | |
470 | sigset_t mask; | |
471 | siginfo_t info; | |
472 | struct lttng_consumer_local_data *ctx = data; | |
473 | ||
1fc79fb4 MD |
474 | health_register(health_consumerd, HEALTH_CONSUMERD_TYPE_METADATA_TIMER); |
475 | ||
2d57de81 MD |
476 | if (testpoint(consumerd_thread_metadata_timer)) { |
477 | goto error_testpoint; | |
478 | } | |
479 | ||
9ce5646a MD |
480 | health_code_update(); |
481 | ||
331744e3 JD |
482 | /* Only self thread will receive signal mask. */ |
483 | setmask(&mask); | |
484 | CMM_STORE_SHARED(timer_signal.tid, pthread_self()); | |
485 | ||
486 | while (1) { | |
9ce5646a MD |
487 | health_code_update(); |
488 | ||
489 | health_poll_entry(); | |
331744e3 | 490 | signr = sigwaitinfo(&mask, &info); |
9ce5646a | 491 | health_poll_exit(); |
331744e3 JD |
492 | if (signr == -1) { |
493 | if (errno != EINTR) { | |
494 | PERROR("sigwaitinfo"); | |
495 | } | |
496 | continue; | |
497 | } else if (signr == LTTNG_CONSUMER_SIG_SWITCH) { | |
498 | metadata_switch_timer(ctx, info.si_signo, &info, NULL); | |
499 | } else if (signr == LTTNG_CONSUMER_SIG_TEARDOWN) { | |
500 | cmm_smp_mb(); | |
501 | CMM_STORE_SHARED(timer_signal.qs_done, 1); | |
502 | cmm_smp_mb(); | |
503 | DBG("Signal timer metadata thread teardown"); | |
d3e2ba59 JD |
504 | } else if (signr == LTTNG_CONSUMER_SIG_LIVE) { |
505 | live_timer(ctx, info.si_signo, &info, NULL); | |
331744e3 JD |
506 | } else { |
507 | ERR("Unexpected signal %d\n", info.si_signo); | |
508 | } | |
509 | } | |
510 | ||
2d57de81 MD |
511 | error_testpoint: |
512 | /* Only reached in testpoint error */ | |
513 | health_error(); | |
1fc79fb4 MD |
514 | health_unregister(health_consumerd); |
515 | ||
516 | /* Never return */ | |
331744e3 JD |
517 | return NULL; |
518 | } |