Commit | Line | Data |
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51230d70 DG |
1 | /* |
2 | * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca> | |
3 | * Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
4 | * Copyright (C) 2013 - David Goulet <dgoulet@efficios.com> | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify it | |
7 | * under the terms of the GNU General Public License, version 2 only, as | |
8 | * published by the Free Software Foundation. | |
9 | * | |
10 | * This program is distributed in the hope that it will be useful, but WITHOUT | |
11 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
12 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
13 | * more details. | |
14 | * | |
15 | * You should have received a copy of the GNU General Public License along with | |
16 | * this program; if not, write to the Free Software Foundation, Inc., 51 | |
17 | * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. | |
18 | */ | |
19 | ||
20 | #define _GNU_SOURCE | |
21 | #include <assert.h> | |
10a50311 | 22 | #include <inttypes.h> |
51230d70 DG |
23 | #include <sys/mman.h> |
24 | #include <unistd.h> | |
25 | ||
26 | #include <common/common.h> | |
1c20f0e2 | 27 | #include <common/index/index.h> |
94d49140 | 28 | #include <common/kernel-consumer/kernel-consumer.h> |
51230d70 DG |
29 | #include <common/relayd/relayd.h> |
30 | #include <common/ust-consumer/ust-consumer.h> | |
31 | ||
32 | #include "consumer-stream.h" | |
33 | ||
34 | /* | |
35 | * RCU call to free stream. MUST only be used with call_rcu(). | |
36 | */ | |
37 | static void free_stream_rcu(struct rcu_head *head) | |
38 | { | |
39 | struct lttng_ht_node_u64 *node = | |
40 | caa_container_of(head, struct lttng_ht_node_u64, head); | |
41 | struct lttng_consumer_stream *stream = | |
42 | caa_container_of(node, struct lttng_consumer_stream, node); | |
43 | ||
44 | pthread_mutex_destroy(&stream->lock); | |
45 | free(stream); | |
46 | } | |
47 | ||
48 | /* | |
49 | * Close stream on the relayd side. This call can destroy a relayd if the | |
50 | * conditions are met. | |
51 | * | |
52 | * A RCU read side lock MUST be acquired if the relayd object was looked up in | |
53 | * a hash table before calling this. | |
54 | */ | |
55 | void consumer_stream_relayd_close(struct lttng_consumer_stream *stream, | |
56 | struct consumer_relayd_sock_pair *relayd) | |
57 | { | |
58 | int ret; | |
59 | ||
60 | assert(stream); | |
61 | assert(relayd); | |
62 | ||
d01178b6 DG |
63 | if (stream->sent_to_relayd) { |
64 | uatomic_dec(&relayd->refcount); | |
65 | assert(uatomic_read(&relayd->refcount) >= 0); | |
66 | } | |
51230d70 DG |
67 | |
68 | /* Closing streams requires to lock the control socket. */ | |
69 | pthread_mutex_lock(&relayd->ctrl_sock_mutex); | |
70 | ret = relayd_send_close_stream(&relayd->control_sock, | |
71 | stream->relayd_stream_id, | |
72 | stream->next_net_seq_num - 1); | |
73 | pthread_mutex_unlock(&relayd->ctrl_sock_mutex); | |
74 | if (ret < 0) { | |
75 | DBG("Unable to close stream on the relayd. Continuing"); | |
76 | /* | |
77 | * Continue here. There is nothing we can do for the relayd. | |
78 | * Chances are that the relayd has closed the socket so we just | |
79 | * continue cleaning up. | |
80 | */ | |
81 | } | |
82 | ||
83 | /* Both conditions are met, we destroy the relayd. */ | |
84 | if (uatomic_read(&relayd->refcount) == 0 && | |
85 | uatomic_read(&relayd->destroy_flag)) { | |
86 | consumer_destroy_relayd(relayd); | |
87 | } | |
10a50311 | 88 | stream->net_seq_idx = (uint64_t) -1ULL; |
d01178b6 | 89 | stream->sent_to_relayd = 0; |
51230d70 DG |
90 | } |
91 | ||
92 | /* | |
93 | * Close stream's file descriptors and, if needed, close stream also on the | |
94 | * relayd side. | |
95 | * | |
96 | * The consumer data lock MUST be acquired. | |
97 | * The stream lock MUST be acquired. | |
98 | */ | |
99 | void consumer_stream_close(struct lttng_consumer_stream *stream) | |
100 | { | |
101 | int ret; | |
102 | struct consumer_relayd_sock_pair *relayd; | |
103 | ||
104 | assert(stream); | |
105 | ||
106 | switch (consumer_data.type) { | |
107 | case LTTNG_CONSUMER_KERNEL: | |
108 | if (stream->mmap_base != NULL) { | |
109 | ret = munmap(stream->mmap_base, stream->mmap_len); | |
110 | if (ret != 0) { | |
111 | PERROR("munmap"); | |
112 | } | |
113 | } | |
114 | ||
115 | if (stream->wait_fd >= 0) { | |
116 | ret = close(stream->wait_fd); | |
117 | if (ret) { | |
118 | PERROR("close"); | |
119 | } | |
10a50311 | 120 | stream->wait_fd = -1; |
51230d70 DG |
121 | } |
122 | break; | |
123 | case LTTNG_CONSUMER32_UST: | |
124 | case LTTNG_CONSUMER64_UST: | |
6d574024 DG |
125 | { |
126 | /* | |
127 | * Special case for the metadata since the wait fd is an internal pipe | |
128 | * polled in the metadata thread. | |
129 | */ | |
130 | if (stream->metadata_flag && stream->chan->monitor) { | |
131 | int rpipe = stream->ust_metadata_poll_pipe[0]; | |
132 | ||
133 | /* | |
134 | * This will stop the channel timer if one and close the write side | |
135 | * of the metadata poll pipe. | |
136 | */ | |
137 | lttng_ustconsumer_close_metadata(stream->chan); | |
138 | if (rpipe >= 0) { | |
139 | ret = close(rpipe); | |
140 | if (ret < 0) { | |
b4a650f3 | 141 | PERROR("closing metadata pipe read side"); |
6d574024 DG |
142 | } |
143 | stream->ust_metadata_poll_pipe[0] = -1; | |
144 | } | |
145 | } | |
51230d70 | 146 | break; |
6d574024 | 147 | } |
51230d70 DG |
148 | default: |
149 | ERR("Unknown consumer_data type"); | |
150 | assert(0); | |
151 | } | |
152 | ||
153 | /* Close output fd. Could be a socket or local file at this point. */ | |
154 | if (stream->out_fd >= 0) { | |
155 | ret = close(stream->out_fd); | |
156 | if (ret) { | |
157 | PERROR("close"); | |
158 | } | |
10a50311 | 159 | stream->out_fd = -1; |
51230d70 DG |
160 | } |
161 | ||
309167d2 JD |
162 | if (stream->index_fd >= 0) { |
163 | ret = close(stream->index_fd); | |
164 | if (ret) { | |
165 | PERROR("close stream index_fd"); | |
166 | } | |
167 | stream->index_fd = -1; | |
168 | } | |
169 | ||
51230d70 DG |
170 | /* Check and cleanup relayd if needed. */ |
171 | rcu_read_lock(); | |
172 | relayd = consumer_find_relayd(stream->net_seq_idx); | |
173 | if (relayd != NULL) { | |
174 | consumer_stream_relayd_close(stream, relayd); | |
175 | } | |
176 | rcu_read_unlock(); | |
177 | } | |
178 | ||
179 | /* | |
180 | * Delete the stream from all possible hash tables. | |
181 | * | |
182 | * The consumer data lock MUST be acquired. | |
183 | * The stream lock MUST be acquired. | |
184 | */ | |
185 | void consumer_stream_delete(struct lttng_consumer_stream *stream, | |
186 | struct lttng_ht *ht) | |
187 | { | |
188 | int ret; | |
189 | struct lttng_ht_iter iter; | |
190 | ||
191 | assert(stream); | |
10a50311 JD |
192 | /* Should NEVER be called not in monitor mode. */ |
193 | assert(stream->chan->monitor); | |
51230d70 DG |
194 | |
195 | rcu_read_lock(); | |
196 | ||
197 | if (ht) { | |
198 | iter.iter.node = &stream->node.node; | |
199 | ret = lttng_ht_del(ht, &iter); | |
200 | assert(!ret); | |
201 | } | |
202 | ||
203 | /* Delete from stream per channel ID hash table. */ | |
204 | iter.iter.node = &stream->node_channel_id.node; | |
205 | /* | |
206 | * The returned value is of no importance. Even if the node is NOT in the | |
207 | * hash table, we continue since we may have been called by a code path | |
208 | * that did not add the stream to a (all) hash table. Same goes for the | |
209 | * next call ht del call. | |
210 | */ | |
211 | (void) lttng_ht_del(consumer_data.stream_per_chan_id_ht, &iter); | |
212 | ||
213 | /* Delete from the global stream list. */ | |
214 | iter.iter.node = &stream->node_session_id.node; | |
215 | /* See the previous ht del on why we ignore the returned value. */ | |
216 | (void) lttng_ht_del(consumer_data.stream_list_ht, &iter); | |
217 | ||
218 | rcu_read_unlock(); | |
219 | ||
6d574024 DG |
220 | if (!stream->metadata_flag) { |
221 | /* Decrement the stream count of the global consumer data. */ | |
222 | assert(consumer_data.stream_count > 0); | |
223 | consumer_data.stream_count--; | |
224 | } | |
51230d70 DG |
225 | } |
226 | ||
227 | /* | |
228 | * Free the given stream within a RCU call. | |
229 | */ | |
230 | void consumer_stream_free(struct lttng_consumer_stream *stream) | |
231 | { | |
232 | assert(stream); | |
233 | ||
234 | call_rcu(&stream->node.head, free_stream_rcu); | |
235 | } | |
236 | ||
237 | /* | |
10a50311 | 238 | * Destroy the stream's buffers of the tracer. |
51230d70 | 239 | */ |
10a50311 | 240 | void consumer_stream_destroy_buffers(struct lttng_consumer_stream *stream) |
51230d70 | 241 | { |
10a50311 JD |
242 | assert(stream); |
243 | ||
244 | switch (consumer_data.type) { | |
245 | case LTTNG_CONSUMER_KERNEL: | |
246 | break; | |
247 | case LTTNG_CONSUMER32_UST: | |
248 | case LTTNG_CONSUMER64_UST: | |
249 | lttng_ustconsumer_del_stream(stream); | |
250 | break; | |
251 | default: | |
252 | ERR("Unknown consumer_data type"); | |
253 | assert(0); | |
254 | } | |
255 | } | |
51230d70 | 256 | |
10a50311 | 257 | /* |
4891ece8 | 258 | * Destroy and close a already created stream. |
10a50311 | 259 | */ |
4891ece8 | 260 | static void destroy_close_stream(struct lttng_consumer_stream *stream) |
10a50311 | 261 | { |
51230d70 DG |
262 | assert(stream); |
263 | ||
4891ece8 | 264 | DBG("Consumer stream destroy monitored key: %" PRIu64, stream->key); |
10a50311 JD |
265 | |
266 | /* Destroy tracer buffers of the stream. */ | |
267 | consumer_stream_destroy_buffers(stream); | |
268 | /* Close down everything including the relayd if one. */ | |
269 | consumer_stream_close(stream); | |
270 | } | |
51230d70 | 271 | |
10a50311 | 272 | /* |
4891ece8 DG |
273 | * Decrement the stream's channel refcount and if down to 0, return the channel |
274 | * pointer so it can be destroyed by the caller or NULL if not. | |
10a50311 | 275 | */ |
4891ece8 DG |
276 | static struct lttng_consumer_channel *unref_channel( |
277 | struct lttng_consumer_stream *stream) | |
10a50311 | 278 | { |
4891ece8 DG |
279 | struct lttng_consumer_channel *free_chan = NULL; |
280 | ||
10a50311 | 281 | assert(stream); |
4891ece8 | 282 | assert(stream->chan); |
10a50311 | 283 | |
4891ece8 DG |
284 | /* Update refcount of channel and see if we need to destroy it. */ |
285 | if (!uatomic_sub_return(&stream->chan->refcount, 1) | |
286 | && !uatomic_read(&stream->chan->nb_init_stream_left)) { | |
287 | free_chan = stream->chan; | |
288 | } | |
51230d70 | 289 | |
4891ece8 | 290 | return free_chan; |
10a50311 | 291 | } |
51230d70 | 292 | |
10a50311 JD |
293 | /* |
294 | * Destroy a stream completely. This will delete, close and free the stream. | |
295 | * Once return, the stream is NO longer usable. Its channel may get destroyed | |
296 | * if conditions are met for a monitored stream. | |
297 | * | |
298 | * This MUST be called WITHOUT the consumer data and stream lock acquired if | |
299 | * the stream is in _monitor_ mode else it does not matter. | |
300 | */ | |
301 | void consumer_stream_destroy(struct lttng_consumer_stream *stream, | |
302 | struct lttng_ht *ht) | |
303 | { | |
304 | assert(stream); | |
305 | ||
306 | /* Stream is in monitor mode. */ | |
4891ece8 | 307 | if (stream->monitor) { |
10a50311 | 308 | struct lttng_consumer_channel *free_chan = NULL; |
51230d70 | 309 | |
4891ece8 DG |
310 | /* |
311 | * This means that the stream was successfully removed from the streams | |
312 | * list of the channel and sent to the right thread managing this | |
313 | * stream thus being globally visible. | |
314 | */ | |
315 | if (stream->globally_visible) { | |
316 | pthread_mutex_lock(&consumer_data.lock); | |
a9838785 | 317 | pthread_mutex_lock(&stream->chan->lock); |
4891ece8 DG |
318 | pthread_mutex_lock(&stream->lock); |
319 | /* Remove every reference of the stream in the consumer. */ | |
320 | consumer_stream_delete(stream, ht); | |
321 | ||
322 | destroy_close_stream(stream); | |
323 | ||
324 | /* Update channel's refcount of the stream. */ | |
325 | free_chan = unref_channel(stream); | |
326 | ||
327 | /* Indicates that the consumer data state MUST be updated after this. */ | |
328 | consumer_data.need_update = 1; | |
329 | ||
330 | pthread_mutex_unlock(&stream->lock); | |
a9838785 | 331 | pthread_mutex_unlock(&stream->chan->lock); |
4891ece8 DG |
332 | pthread_mutex_unlock(&consumer_data.lock); |
333 | } else { | |
334 | /* | |
335 | * If the stream is not visible globally, this needs to be done | |
336 | * outside of the consumer data lock section. | |
337 | */ | |
338 | free_chan = unref_channel(stream); | |
10a50311 JD |
339 | } |
340 | ||
10a50311 JD |
341 | if (free_chan) { |
342 | consumer_del_channel(free_chan); | |
343 | } | |
344 | } else { | |
4891ece8 | 345 | destroy_close_stream(stream); |
51230d70 DG |
346 | } |
347 | ||
348 | /* Free stream within a RCU call. */ | |
349 | consumer_stream_free(stream); | |
350 | } | |
1c20f0e2 JD |
351 | |
352 | /* | |
353 | * Write index of a specific stream either on the relayd or local disk. | |
354 | * | |
355 | * Return 0 on success or else a negative value. | |
356 | */ | |
357 | int consumer_stream_write_index(struct lttng_consumer_stream *stream, | |
50adc264 | 358 | struct ctf_packet_index *index) |
1c20f0e2 JD |
359 | { |
360 | int ret; | |
361 | struct consumer_relayd_sock_pair *relayd; | |
362 | ||
363 | assert(stream); | |
364 | assert(index); | |
365 | ||
366 | rcu_read_lock(); | |
367 | relayd = consumer_find_relayd(stream->net_seq_idx); | |
368 | if (relayd) { | |
3ccf4e95 | 369 | pthread_mutex_lock(&relayd->ctrl_sock_mutex); |
1c20f0e2 JD |
370 | ret = relayd_send_index(&relayd->control_sock, index, |
371 | stream->relayd_stream_id, stream->next_net_seq_num - 1); | |
3ccf4e95 | 372 | pthread_mutex_unlock(&relayd->ctrl_sock_mutex); |
1c20f0e2 | 373 | } else { |
6cd525e8 MD |
374 | ssize_t size_ret; |
375 | ||
376 | size_ret = index_write(stream->index_fd, index, | |
50adc264 JD |
377 | sizeof(struct ctf_packet_index)); |
378 | if (size_ret < sizeof(struct ctf_packet_index)) { | |
6cd525e8 MD |
379 | ret = -1; |
380 | } else { | |
381 | ret = 0; | |
382 | } | |
1c20f0e2 JD |
383 | } |
384 | if (ret < 0) { | |
385 | goto error; | |
386 | } | |
387 | ||
388 | error: | |
389 | rcu_read_unlock(); | |
390 | return ret; | |
391 | } | |
94d49140 JD |
392 | |
393 | /* | |
394 | * Synchronize the metadata using a given session ID. A successful acquisition | |
395 | * of a metadata stream will trigger a request to the session daemon and a | |
396 | * snapshot so the metadata thread can consume it. | |
397 | * | |
398 | * This function call is a rendez-vous point between the metadata thread and | |
399 | * the data thread. | |
400 | * | |
401 | * Return 0 on success or else a negative value. | |
402 | */ | |
403 | int consumer_stream_sync_metadata(struct lttng_consumer_local_data *ctx, | |
404 | uint64_t session_id) | |
405 | { | |
406 | int ret; | |
407 | struct lttng_consumer_stream *metadata = NULL, *stream = NULL; | |
408 | struct lttng_ht_iter iter; | |
409 | struct lttng_ht *ht; | |
410 | ||
411 | assert(ctx); | |
412 | ||
413 | /* Ease our life a bit. */ | |
414 | ht = consumer_data.stream_list_ht; | |
415 | ||
416 | rcu_read_lock(); | |
417 | ||
418 | /* Search the metadata associated with the session id of the given stream. */ | |
419 | ||
420 | cds_lfht_for_each_entry_duplicate(ht->ht, | |
421 | ht->hash_fct(&session_id, lttng_ht_seed), ht->match_fct, | |
422 | &session_id, &iter.iter, stream, node_session_id.node) { | |
423 | if (stream->metadata_flag) { | |
424 | metadata = stream; | |
425 | break; | |
426 | } | |
427 | } | |
428 | if (!metadata) { | |
429 | ret = 0; | |
430 | goto end_unlock_rcu; | |
431 | } | |
432 | ||
433 | /* | |
434 | * In UST, since we have to write the metadata from the cache packet | |
435 | * by packet, we might need to start this procedure multiple times | |
436 | * until all the metadata from the cache has been extracted. | |
437 | */ | |
438 | do { | |
439 | /* | |
440 | * Steps : | |
441 | * - Lock the metadata stream | |
442 | * - Check if metadata stream node was deleted before locking. | |
443 | * - if yes, release and return success | |
444 | * - Check if new metadata is ready (flush + snapshot pos) | |
445 | * - If nothing : release and return. | |
446 | * - Lock the metadata_rdv_lock | |
447 | * - Unlock the metadata stream | |
448 | * - cond_wait on metadata_rdv to wait the wakeup from the | |
449 | * metadata thread | |
450 | * - Unlock the metadata_rdv_lock | |
451 | */ | |
452 | pthread_mutex_lock(&metadata->lock); | |
453 | ||
454 | /* | |
455 | * There is a possibility that we were able to acquire a reference on the | |
456 | * stream from the RCU hash table but between then and now, the node might | |
457 | * have been deleted just before the lock is acquired. Thus, after locking, | |
458 | * we make sure the metadata node has not been deleted which means that the | |
459 | * buffers are closed. | |
460 | * | |
461 | * In that case, there is no need to sync the metadata hence returning a | |
462 | * success return code. | |
463 | */ | |
464 | ret = cds_lfht_is_node_deleted(&metadata->node.node); | |
465 | if (ret) { | |
466 | ret = 0; | |
467 | goto end_unlock_mutex; | |
468 | } | |
469 | ||
470 | switch (ctx->type) { | |
471 | case LTTNG_CONSUMER_KERNEL: | |
472 | /* | |
473 | * Empty the metadata cache and flush the current stream. | |
474 | */ | |
475 | ret = lttng_kconsumer_sync_metadata(metadata); | |
476 | break; | |
477 | case LTTNG_CONSUMER32_UST: | |
478 | case LTTNG_CONSUMER64_UST: | |
479 | /* | |
480 | * Ask the sessiond if we have new metadata waiting and update the | |
481 | * consumer metadata cache. | |
482 | */ | |
483 | ret = lttng_ustconsumer_sync_metadata(ctx, metadata); | |
484 | break; | |
485 | default: | |
486 | assert(0); | |
487 | ret = -1; | |
488 | break; | |
489 | } | |
490 | /* | |
491 | * Error or no new metadata, we exit here. | |
492 | */ | |
493 | if (ret <= 0 || ret == ENODATA) { | |
494 | goto end_unlock_mutex; | |
495 | } | |
496 | ||
497 | /* | |
498 | * At this point, new metadata have been flushed, so we wait on the | |
499 | * rendez-vous point for the metadata thread to wake us up when it | |
500 | * finishes consuming the metadata and continue execution. | |
501 | */ | |
502 | ||
503 | pthread_mutex_lock(&metadata->metadata_rdv_lock); | |
504 | ||
505 | /* | |
506 | * Release metadata stream lock so the metadata thread can process it. | |
507 | */ | |
508 | pthread_mutex_unlock(&metadata->lock); | |
509 | ||
510 | /* | |
511 | * Wait on the rendez-vous point. Once woken up, it means the metadata was | |
512 | * consumed and thus synchronization is achieved. | |
513 | */ | |
514 | pthread_cond_wait(&metadata->metadata_rdv, &metadata->metadata_rdv_lock); | |
515 | pthread_mutex_unlock(&metadata->metadata_rdv_lock); | |
516 | } while (ret == EAGAIN); | |
517 | ||
518 | ret = 0; | |
519 | goto end_unlock_rcu; | |
520 | ||
521 | end_unlock_mutex: | |
522 | pthread_mutex_unlock(&metadata->lock); | |
523 | end_unlock_rcu: | |
524 | rcu_read_unlock(); | |
525 | return ret; | |
526 | } |