Fix: consumer add channel return value was positive on error
[lttng-tools.git] / src / common / ust-consumer / ust-consumer.c
CommitLineData
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1/*
2 * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4 *
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5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License, version 2 only,
7 * as published by the Free Software Foundation.
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8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
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14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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17 */
18
19#define _GNU_SOURCE
20#include <assert.h>
f02e1e8a 21#include <lttng/ust-ctl.h>
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22#include <poll.h>
23#include <pthread.h>
24#include <stdlib.h>
25#include <string.h>
26#include <sys/mman.h>
27#include <sys/socket.h>
dbb5dfe6 28#include <sys/stat.h>
3bd1e081 29#include <sys/types.h>
77c7c900 30#include <inttypes.h>
3bd1e081 31#include <unistd.h>
ffe60014 32#include <urcu/list.h>
331744e3 33#include <signal.h>
0857097f 34
990570ed 35#include <common/common.h>
10a8a223 36#include <common/sessiond-comm/sessiond-comm.h>
00e2e675 37#include <common/relayd/relayd.h>
dbb5dfe6 38#include <common/compat/fcntl.h>
331744e3
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39#include <common/consumer-metadata-cache.h>
40#include <common/consumer-timer.h>
fe4477ee 41#include <common/utils.h>
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42
43#include "ust-consumer.h"
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44
45extern struct lttng_consumer_global_data consumer_data;
46extern int consumer_poll_timeout;
47extern volatile int consumer_quit;
48
49/*
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50 * Free channel object and all streams associated with it. This MUST be used
51 * only and only if the channel has _NEVER_ been added to the global channel
52 * hash table.
3bd1e081 53 */
ffe60014 54static void destroy_channel(struct lttng_consumer_channel *channel)
3bd1e081 55{
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56 struct lttng_consumer_stream *stream, *stmp;
57
58 assert(channel);
59
60 DBG("UST consumer cleaning stream list");
61
62 cds_list_for_each_entry_safe(stream, stmp, &channel->streams.head,
63 send_node) {
64 cds_list_del(&stream->send_node);
65 ustctl_destroy_stream(stream->ustream);
66 free(stream);
67 }
68
69 /*
70 * If a channel is available meaning that was created before the streams
71 * were, delete it.
72 */
73 if (channel->uchan) {
74 lttng_ustconsumer_del_channel(channel);
75 }
76 free(channel);
77}
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78
79/*
ffe60014 80 * Add channel to internal consumer state.
3bd1e081 81 *
ffe60014 82 * Returns 0 on success or else a negative value.
3bd1e081 83 */
ffe60014
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84static int add_channel(struct lttng_consumer_channel *channel,
85 struct lttng_consumer_local_data *ctx)
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86{
87 int ret = 0;
88
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89 assert(channel);
90 assert(ctx);
91
92 if (ctx->on_recv_channel != NULL) {
93 ret = ctx->on_recv_channel(channel);
94 if (ret == 0) {
d8ef542d 95 ret = consumer_add_channel(channel, ctx);
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96 } else if (ret < 0) {
97 /* Most likely an ENOMEM. */
98 lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_OUTFD_ERROR);
99 goto error;
100 }
101 } else {
d8ef542d 102 ret = consumer_add_channel(channel, ctx);
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103 }
104
d88aee68 105 DBG("UST consumer channel added (key: %" PRIu64 ")", channel->key);
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106
107error:
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108 return ret;
109}
110
111/*
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112 * Allocate and return a consumer channel object.
113 */
114static struct lttng_consumer_channel *allocate_channel(uint64_t session_id,
115 const char *pathname, const char *name, uid_t uid, gid_t gid,
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116 int relayd_id, uint64_t key, enum lttng_event_output output,
117 uint64_t tracefile_size, uint64_t tracefile_count)
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118{
119 assert(pathname);
120 assert(name);
121
122 return consumer_allocate_channel(key, session_id, pathname, name, uid, gid,
1624d5b7 123 relayd_id, output, tracefile_size, tracefile_count);
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124}
125
126/*
127 * Allocate and return a consumer stream object. If _alloc_ret is not NULL, the
128 * error value if applicable is set in it else it is kept untouched.
3bd1e081 129 *
ffe60014 130 * Return NULL on error else the newly allocated stream object.
3bd1e081 131 */
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132static struct lttng_consumer_stream *allocate_stream(int cpu, int key,
133 struct lttng_consumer_channel *channel,
134 struct lttng_consumer_local_data *ctx, int *_alloc_ret)
135{
136 int alloc_ret;
137 struct lttng_consumer_stream *stream = NULL;
138
139 assert(channel);
140 assert(ctx);
141
142 stream = consumer_allocate_stream(channel->key,
143 key,
144 LTTNG_CONSUMER_ACTIVE_STREAM,
145 channel->name,
146 channel->uid,
147 channel->gid,
148 channel->relayd_id,
149 channel->session_id,
150 cpu,
151 &alloc_ret,
152 channel->type);
153 if (stream == NULL) {
154 switch (alloc_ret) {
155 case -ENOENT:
156 /*
157 * We could not find the channel. Can happen if cpu hotplug
158 * happens while tearing down.
159 */
160 DBG3("Could not find channel");
161 break;
162 case -ENOMEM:
163 case -EINVAL:
164 default:
165 lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_OUTFD_ERROR);
166 break;
167 }
168 goto error;
169 }
170
171 stream->chan = channel;
172
173error:
174 if (_alloc_ret) {
175 *_alloc_ret = alloc_ret;
176 }
177 return stream;
178}
179
180/*
181 * Send the given stream pointer to the corresponding thread.
182 *
183 * Returns 0 on success else a negative value.
184 */
185static int send_stream_to_thread(struct lttng_consumer_stream *stream,
186 struct lttng_consumer_local_data *ctx)
187{
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188 int ret;
189 struct lttng_pipe *stream_pipe;
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190
191 /* Get the right pipe where the stream will be sent. */
192 if (stream->metadata_flag) {
dae10966 193 stream_pipe = ctx->consumer_metadata_pipe;
ffe60014 194 } else {
dae10966 195 stream_pipe = ctx->consumer_data_pipe;
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196 }
197
dae10966 198 ret = lttng_pipe_write(stream_pipe, &stream, sizeof(stream));
ffe60014 199 if (ret < 0) {
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200 ERR("Consumer write %s stream to pipe %d",
201 stream->metadata_flag ? "metadata" : "data",
202 lttng_pipe_get_writefd(stream_pipe));
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203 }
204
205 return ret;
206}
207
208/*
209 * Search for a relayd object related to the stream. If found, send the stream
210 * to the relayd.
211 *
212 * On success, returns 0 else a negative value.
213 */
214static int send_stream_to_relayd(struct lttng_consumer_stream *stream)
215{
216 int ret = 0;
217 struct consumer_relayd_sock_pair *relayd;
218
219 assert(stream);
220
221 relayd = consumer_find_relayd(stream->net_seq_idx);
222 if (relayd != NULL) {
223 pthread_mutex_lock(&relayd->ctrl_sock_mutex);
224 /* Add stream on the relayd */
225 ret = relayd_add_stream(&relayd->control_sock, stream->name,
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226 stream->chan->pathname, &stream->relayd_stream_id,
227 stream->chan->tracefile_size,
228 stream->chan->tracefile_count);
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229 pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
230 if (ret < 0) {
231 goto error;
232 }
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233 } else if (stream->net_seq_idx != (uint64_t) -1ULL) {
234 ERR("Network sequence index %" PRIu64 " unknown. Not adding stream.",
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235 stream->net_seq_idx);
236 ret = -1;
237 goto error;
238 }
239
240error:
241 return ret;
242}
243
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244/*
245 * Create streams for the given channel using liblttng-ust-ctl.
246 *
247 * Return 0 on success else a negative value.
248 */
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249static int create_ust_streams(struct lttng_consumer_channel *channel,
250 struct lttng_consumer_local_data *ctx)
251{
252 int ret, cpu = 0;
253 struct ustctl_consumer_stream *ustream;
254 struct lttng_consumer_stream *stream;
255
256 assert(channel);
257 assert(ctx);
258
259 /*
260 * While a stream is available from ustctl. When NULL is returned, we've
261 * reached the end of the possible stream for the channel.
262 */
263 while ((ustream = ustctl_create_stream(channel->uchan, cpu))) {
264 int wait_fd;
265
749d339a 266 wait_fd = ustctl_stream_get_wait_fd(ustream);
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267
268 /* Allocate consumer stream object. */
269 stream = allocate_stream(cpu, wait_fd, channel, ctx, &ret);
270 if (!stream) {
271 goto error_alloc;
272 }
273 stream->ustream = ustream;
274 /*
275 * Store it so we can save multiple function calls afterwards since
276 * this value is used heavily in the stream threads. This is UST
277 * specific so this is why it's done after allocation.
278 */
279 stream->wait_fd = wait_fd;
280
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281 /*
282 * Increment channel refcount since the channel reference has now been
283 * assigned in the allocation process above.
284 */
285 uatomic_inc(&stream->chan->refcount);
286
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287 /*
288 * Order is important this is why a list is used. On error, the caller
289 * should clean this list.
290 */
291 cds_list_add_tail(&stream->send_node, &channel->streams.head);
292
293 ret = ustctl_get_max_subbuf_size(stream->ustream,
294 &stream->max_sb_size);
295 if (ret < 0) {
296 ERR("ustctl_get_max_subbuf_size failed for stream %s",
297 stream->name);
298 goto error;
299 }
300
301 /* Do actions once stream has been received. */
302 if (ctx->on_recv_stream) {
303 ret = ctx->on_recv_stream(stream);
304 if (ret < 0) {
305 goto error;
306 }
307 }
308
d88aee68 309 DBG("UST consumer add stream %s (key: %" PRIu64 ") with relayd id %" PRIu64,
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310 stream->name, stream->key, stream->relayd_stream_id);
311
312 /* Set next CPU stream. */
313 channel->streams.count = ++cpu;
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314
315 /* Keep stream reference when creating metadata. */
316 if (channel->type == CONSUMER_CHANNEL_TYPE_METADATA) {
317 channel->metadata_stream = stream;
318 }
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319 }
320
321 return 0;
322
323error:
324error_alloc:
325 return ret;
326}
327
328/*
329 * Create an UST channel with the given attributes and send it to the session
330 * daemon using the ust ctl API.
331 *
332 * Return 0 on success or else a negative value.
333 */
334static int create_ust_channel(struct ustctl_consumer_channel_attr *attr,
335 struct ustctl_consumer_channel **chanp)
336{
337 int ret;
338 struct ustctl_consumer_channel *channel;
339
340 assert(attr);
341 assert(chanp);
342
343 DBG3("Creating channel to ustctl with attr: [overwrite: %d, "
344 "subbuf_size: %" PRIu64 ", num_subbuf: %" PRIu64 ", "
345 "switch_timer_interval: %u, read_timer_interval: %u, "
346 "output: %d, type: %d", attr->overwrite, attr->subbuf_size,
347 attr->num_subbuf, attr->switch_timer_interval,
348 attr->read_timer_interval, attr->output, attr->type);
349
350 channel = ustctl_create_channel(attr);
351 if (!channel) {
352 ret = -1;
353 goto error_create;
354 }
355
356 *chanp = channel;
357
358 return 0;
359
360error_create:
361 return ret;
362}
363
d88aee68
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364/*
365 * Send a single given stream to the session daemon using the sock.
366 *
367 * Return 0 on success else a negative value.
368 */
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369static int send_sessiond_stream(int sock, struct lttng_consumer_stream *stream)
370{
371 int ret;
372
373 assert(stream);
374 assert(sock >= 0);
375
d88aee68 376 DBG2("UST consumer sending stream %" PRIu64 " to sessiond", stream->key);
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377
378 /* Send stream to session daemon. */
379 ret = ustctl_send_stream_to_sessiond(sock, stream->ustream);
380 if (ret < 0) {
381 goto error;
382 }
383
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384error:
385 return ret;
386}
387
388/*
389 * Send channel to sessiond.
390 *
d88aee68 391 * Return 0 on success or else a negative value.
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392 */
393static int send_sessiond_channel(int sock,
394 struct lttng_consumer_channel *channel,
395 struct lttng_consumer_local_data *ctx, int *relayd_error)
396{
397 int ret;
398 struct lttng_consumer_stream *stream;
399
400 assert(channel);
401 assert(ctx);
402 assert(sock >= 0);
403
404 DBG("UST consumer sending channel %s to sessiond", channel->name);
405
406 /* Send channel to sessiond. */
407 ret = ustctl_send_channel_to_sessiond(sock, channel->uchan);
408 if (ret < 0) {
409 goto error;
410 }
411
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412 ret = ustctl_channel_close_wakeup_fd(channel->uchan);
413 if (ret < 0) {
414 goto error;
415 }
416
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417 /* The channel was sent successfully to the sessiond at this point. */
418 cds_list_for_each_entry(stream, &channel->streams.head, send_node) {
419 /* Try to send the stream to the relayd if one is available. */
420 ret = send_stream_to_relayd(stream);
421 if (ret < 0) {
422 /*
423 * Flag that the relayd was the problem here probably due to a
424 * communicaton error on the socket.
425 */
426 if (relayd_error) {
427 *relayd_error = 1;
428 }
429 goto error;
430 }
431
432 /* Send stream to session daemon. */
433 ret = send_sessiond_stream(sock, stream);
434 if (ret < 0) {
435 goto error;
436 }
437 }
438
439 /* Tell sessiond there is no more stream. */
440 ret = ustctl_send_stream_to_sessiond(sock, NULL);
441 if (ret < 0) {
442 goto error;
443 }
444
445 DBG("UST consumer NULL stream sent to sessiond");
446
447 return 0;
448
449error:
450 return ret;
451}
452
453/*
454 * Creates a channel and streams and add the channel it to the channel internal
455 * state. The created stream must ONLY be sent once the GET_CHANNEL command is
456 * received.
457 *
458 * Return 0 on success or else, a negative value is returned and the channel
459 * MUST be destroyed by consumer_del_channel().
460 */
461static int ask_channel(struct lttng_consumer_local_data *ctx, int sock,
462 struct lttng_consumer_channel *channel,
463 struct ustctl_consumer_channel_attr *attr)
3bd1e081
MD
464{
465 int ret;
466
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467 assert(ctx);
468 assert(channel);
469 assert(attr);
470
471 /*
472 * This value is still used by the kernel consumer since for the kernel,
473 * the stream ownership is not IN the consumer so we need to have the
474 * number of left stream that needs to be initialized so we can know when
475 * to delete the channel (see consumer.c).
476 *
477 * As for the user space tracer now, the consumer creates and sends the
478 * stream to the session daemon which only sends them to the application
479 * once every stream of a channel is received making this value useless
480 * because we they will be added to the poll thread before the application
481 * receives them. This ensures that a stream can not hang up during
482 * initilization of a channel.
483 */
484 channel->nb_init_stream_left = 0;
485
486 /* The reply msg status is handled in the following call. */
487 ret = create_ust_channel(attr, &channel->uchan);
488 if (ret < 0) {
489 goto error;
3bd1e081
MD
490 }
491
d8ef542d
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492 channel->wait_fd = ustctl_channel_get_wait_fd(channel->uchan);
493
ffe60014
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494 /* Open all streams for this channel. */
495 ret = create_ust_streams(channel, ctx);
496 if (ret < 0) {
497 goto error;
498 }
499
500error:
3bd1e081
MD
501 return ret;
502}
503
d88aee68
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504/*
505 * Send all stream of a channel to the right thread handling it.
506 *
507 * On error, return a negative value else 0 on success.
508 */
509static int send_streams_to_thread(struct lttng_consumer_channel *channel,
510 struct lttng_consumer_local_data *ctx)
511{
512 int ret = 0;
513 struct lttng_consumer_stream *stream, *stmp;
514
515 assert(channel);
516 assert(ctx);
517
518 /* Send streams to the corresponding thread. */
519 cds_list_for_each_entry_safe(stream, stmp, &channel->streams.head,
520 send_node) {
521 /* Sending the stream to the thread. */
522 ret = send_stream_to_thread(stream, ctx);
523 if (ret < 0) {
524 /*
525 * If we are unable to send the stream to the thread, there is
526 * a big problem so just stop everything.
527 */
528 goto error;
529 }
530
531 /* Remove node from the channel stream list. */
532 cds_list_del(&stream->send_node);
533 }
534
535error:
536 return ret;
537}
538
539/*
540 * Write metadata to the given channel using ustctl to convert the string to
541 * the ringbuffer.
331744e3
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542 * Called only from consumer_metadata_cache_write.
543 * The metadata cache lock MUST be acquired to write in the cache.
d88aee68
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544 *
545 * Return 0 on success else a negative value.
546 */
331744e3 547int lttng_ustconsumer_push_metadata(struct lttng_consumer_channel *metadata,
d88aee68
DG
548 const char *metadata_str, uint64_t target_offset, uint64_t len)
549{
550 int ret;
551
552 assert(metadata);
553 assert(metadata_str);
554
555 DBG("UST consumer writing metadata to channel %s", metadata->name);
556
73811ecc
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557 if (!metadata->metadata_stream) {
558 ret = 0;
559 goto error;
560 }
561
331744e3
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562 assert(target_offset <= metadata->metadata_cache->max_offset);
563 ret = ustctl_write_metadata_to_channel(metadata->uchan,
564 metadata_str + target_offset, len);
d88aee68 565 if (ret < 0) {
8fd623e0 566 ERR("ustctl write metadata fail with ret %d, len %" PRIu64, ret, len);
d88aee68
DG
567 goto error;
568 }
d88aee68
DG
569
570 ustctl_flush_buffer(metadata->metadata_stream->ustream, 1);
571
572error:
573 return ret;
574}
575
7972aab2
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576/*
577 * Flush channel's streams using the given key to retrieve the channel.
578 *
579 * Return 0 on success else an LTTng error code.
580 */
581static int flush_channel(uint64_t chan_key)
582{
583 int ret = 0;
584 struct lttng_consumer_channel *channel;
585 struct lttng_consumer_stream *stream;
586 struct lttng_ht *ht;
587 struct lttng_ht_iter iter;
588
8fd623e0 589 DBG("UST consumer flush channel key %" PRIu64, chan_key);
7972aab2 590
a500c257 591 rcu_read_lock();
7972aab2
DG
592 channel = consumer_find_channel(chan_key);
593 if (!channel) {
8fd623e0 594 ERR("UST consumer flush channel %" PRIu64 " not found", chan_key);
7972aab2
DG
595 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
596 goto error;
597 }
598
599 ht = consumer_data.stream_per_chan_id_ht;
600
601 /* For each stream of the channel id, flush it. */
7972aab2
DG
602 cds_lfht_for_each_entry_duplicate(ht->ht,
603 ht->hash_fct(&channel->key, lttng_ht_seed), ht->match_fct,
604 &channel->key, &iter.iter, stream, node_channel_id.node) {
605 ustctl_flush_buffer(stream->ustream, 1);
606 }
7972aab2 607error:
a500c257 608 rcu_read_unlock();
7972aab2
DG
609 return ret;
610}
611
d88aee68
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612/*
613 * Close metadata stream wakeup_fd using the given key to retrieve the channel.
a500c257 614 * RCU read side lock MUST be acquired before calling this function.
d88aee68
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615 *
616 * Return 0 on success else an LTTng error code.
617 */
618static int close_metadata(uint64_t chan_key)
619{
ea88ca2a 620 int ret = 0;
d88aee68
DG
621 struct lttng_consumer_channel *channel;
622
8fd623e0 623 DBG("UST consumer close metadata key %" PRIu64, chan_key);
d88aee68
DG
624
625 channel = consumer_find_channel(chan_key);
626 if (!channel) {
84cc9aa0
DG
627 /*
628 * This is possible if the metadata thread has issue a delete because
629 * the endpoint point of the stream hung up. There is no way the
630 * session daemon can know about it thus use a DBG instead of an actual
631 * error.
632 */
633 DBG("UST consumer close metadata %" PRIu64 " not found", chan_key);
d88aee68
DG
634 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
635 goto error;
636 }
637
ea88ca2a 638 pthread_mutex_lock(&consumer_data.lock);
73811ecc
DG
639
640 if (cds_lfht_is_node_deleted(&channel->node.node)) {
641 goto error_unlock;
642 }
643
644 if (channel->switch_timer_enabled == 1) {
645 DBG("Deleting timer on metadata channel");
646 consumer_timer_switch_stop(channel);
647 }
648
649 if (channel->metadata_stream) {
ea88ca2a
MD
650 ret = ustctl_stream_close_wakeup_fd(channel->metadata_stream->ustream);
651 if (ret < 0) {
652 ERR("UST consumer unable to close fd of metadata (ret: %d)", ret);
653 ret = LTTCOMM_CONSUMERD_ERROR_METADATA;
654 goto error_unlock;
655 }
331744e3 656 }
d88aee68 657
ea88ca2a
MD
658error_unlock:
659 pthread_mutex_unlock(&consumer_data.lock);
d88aee68
DG
660error:
661 return ret;
662}
663
664/*
665 * RCU read side lock MUST be acquired before calling this function.
666 *
667 * Return 0 on success else an LTTng error code.
668 */
669static int setup_metadata(struct lttng_consumer_local_data *ctx, uint64_t key)
670{
671 int ret;
672 struct lttng_consumer_channel *metadata;
673
8fd623e0 674 DBG("UST consumer setup metadata key %" PRIu64, key);
d88aee68
DG
675
676 metadata = consumer_find_channel(key);
677 if (!metadata) {
678 ERR("UST consumer push metadata %" PRIu64 " not found", key);
679 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
680 goto error;
681 }
682
683 /*
684 * Send metadata stream to relayd if one available. Availability is
685 * known if the stream is still in the list of the channel.
686 */
687 if (cds_list_empty(&metadata->streams.head)) {
688 ERR("Metadata channel key %" PRIu64 ", no stream available.", key);
689 ret = LTTCOMM_CONSUMERD_ERROR_METADATA;
690 goto error;
691 }
692
693 /* Send metadata stream to relayd if needed. */
694 ret = send_stream_to_relayd(metadata->metadata_stream);
695 if (ret < 0) {
696 ret = LTTCOMM_CONSUMERD_ERROR_METADATA;
697 goto error;
698 }
699
700 ret = send_streams_to_thread(metadata, ctx);
701 if (ret < 0) {
702 /*
703 * If we are unable to send the stream to the thread, there is
704 * a big problem so just stop everything.
705 */
706 ret = LTTCOMM_CONSUMERD_FATAL;
707 goto error;
708 }
709 /* List MUST be empty after or else it could be reused. */
710 assert(cds_list_empty(&metadata->streams.head));
711
712 ret = 0;
713
714error:
715 return ret;
716}
717
331744e3
JD
718/*
719 * Receive the metadata updates from the sessiond.
720 */
721int lttng_ustconsumer_recv_metadata(int sock, uint64_t key, uint64_t offset,
722 uint64_t len, struct lttng_consumer_channel *channel)
723{
724 int ret, ret_code = LTTNG_OK;
725 char *metadata_str;
726
8fd623e0 727 DBG("UST consumer push metadata key %" PRIu64 " of len %" PRIu64, key, len);
331744e3
JD
728
729 metadata_str = zmalloc(len * sizeof(char));
730 if (!metadata_str) {
731 PERROR("zmalloc metadata string");
732 ret_code = LTTCOMM_CONSUMERD_ENOMEM;
733 goto end;
734 }
735
736 /* Receive metadata string. */
737 ret = lttcomm_recv_unix_sock(sock, metadata_str, len);
738 if (ret < 0) {
739 /* Session daemon is dead so return gracefully. */
740 ret_code = ret;
741 goto end_free;
742 }
743
73811ecc
DG
744 /*
745 * XXX: The consumer data lock is acquired before calling metadata cache
746 * write which calls push metadata that MUST be protected by the consumer
747 * lock in order to be able to check the validity of the metadata stream of
748 * the channel.
749 *
750 * Note that this will be subject to change to better fine grained locking
751 * and ultimately try to get rid of this global consumer data lock.
752 */
753 pthread_mutex_lock(&consumer_data.lock);
754
331744e3
JD
755 pthread_mutex_lock(&channel->metadata_cache->lock);
756 ret = consumer_metadata_cache_write(channel, offset, len, metadata_str);
757 if (ret < 0) {
758 /* Unable to handle metadata. Notify session daemon. */
759 ret_code = LTTCOMM_CONSUMERD_ERROR_METADATA;
a32bd775
DG
760 /*
761 * Skip metadata flush on write error since the offset and len might
762 * not have been updated which could create an infinite loop below when
763 * waiting for the metadata cache to be flushed.
764 */
765 pthread_mutex_unlock(&channel->metadata_cache->lock);
766 pthread_mutex_unlock(&consumer_data.lock);
767 goto end_free;
331744e3
JD
768 }
769 pthread_mutex_unlock(&channel->metadata_cache->lock);
73811ecc 770 pthread_mutex_unlock(&consumer_data.lock);
331744e3
JD
771
772 while (consumer_metadata_cache_flushed(channel, offset + len)) {
773 DBG("Waiting for metadata to be flushed");
774 usleep(DEFAULT_METADATA_AVAILABILITY_WAIT_TIME);
775 }
776
777end_free:
778 free(metadata_str);
779end:
780 return ret_code;
781}
782
4cbc1a04
DG
783/*
784 * Receive command from session daemon and process it.
785 *
786 * Return 1 on success else a negative value or 0.
787 */
3bd1e081
MD
788int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data *ctx,
789 int sock, struct pollfd *consumer_sockpoll)
790{
791 ssize_t ret;
f50f23d9 792 enum lttng_error_code ret_code = LTTNG_OK;
3bd1e081 793 struct lttcomm_consumer_msg msg;
ffe60014 794 struct lttng_consumer_channel *channel = NULL;
3bd1e081
MD
795
796 ret = lttcomm_recv_unix_sock(sock, &msg, sizeof(msg));
797 if (ret != sizeof(msg)) {
173af62f
DG
798 DBG("Consumer received unexpected message size %zd (expects %zu)",
799 ret, sizeof(msg));
ffe60014 800 lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_ERROR_RECV_CMD);
3be74084
DG
801 /*
802 * The ret value might 0 meaning an orderly shutdown but this is ok
803 * since the caller handles this.
804 */
489f70e9
MD
805 if (ret > 0) {
806 ret = -1;
807 }
3bd1e081
MD
808 return ret;
809 }
810 if (msg.cmd_type == LTTNG_CONSUMER_STOP) {
f50f23d9
DG
811 /*
812 * Notify the session daemon that the command is completed.
813 *
814 * On transport layer error, the function call will print an error
815 * message so handling the returned code is a bit useless since we
816 * return an error code anyway.
817 */
818 (void) consumer_send_status_msg(sock, ret_code);
3bd1e081
MD
819 return -ENOENT;
820 }
821
3f8e211f 822 /* relayd needs RCU read-side lock */
b0b335c8
MD
823 rcu_read_lock();
824
3bd1e081 825 switch (msg.cmd_type) {
00e2e675
DG
826 case LTTNG_CONSUMER_ADD_RELAYD_SOCKET:
827 {
f50f23d9 828 /* Session daemon status message are handled in the following call. */
7735ef9e
DG
829 ret = consumer_add_relayd_socket(msg.u.relayd_sock.net_index,
830 msg.u.relayd_sock.type, ctx, sock, consumer_sockpoll,
46e6455f 831 &msg.u.relayd_sock.sock, msg.u.relayd_sock.session_id);
00e2e675
DG
832 goto end_nosignal;
833 }
173af62f
DG
834 case LTTNG_CONSUMER_DESTROY_RELAYD:
835 {
a6ba4fe1 836 uint64_t index = msg.u.destroy_relayd.net_seq_idx;
173af62f
DG
837 struct consumer_relayd_sock_pair *relayd;
838
a6ba4fe1 839 DBG("UST consumer destroying relayd %" PRIu64, index);
173af62f
DG
840
841 /* Get relayd reference if exists. */
a6ba4fe1 842 relayd = consumer_find_relayd(index);
173af62f 843 if (relayd == NULL) {
3448e266 844 DBG("Unable to find relayd %" PRIu64, index);
f50f23d9 845 ret_code = LTTNG_ERR_NO_CONSUMER;
173af62f
DG
846 }
847
a6ba4fe1
DG
848 /*
849 * Each relayd socket pair has a refcount of stream attached to it
850 * which tells if the relayd is still active or not depending on the
851 * refcount value.
852 *
853 * This will set the destroy flag of the relayd object and destroy it
854 * if the refcount reaches zero when called.
855 *
856 * The destroy can happen either here or when a stream fd hangs up.
857 */
f50f23d9
DG
858 if (relayd) {
859 consumer_flag_relayd_for_destroy(relayd);
860 }
861
d88aee68 862 goto end_msg_sessiond;
173af62f 863 }
3bd1e081
MD
864 case LTTNG_CONSUMER_UPDATE_STREAM:
865 {
3f8e211f 866 rcu_read_unlock();
7ad0a0cb 867 return -ENOSYS;
3bd1e081 868 }
6d805429 869 case LTTNG_CONSUMER_DATA_PENDING:
53632229 870 {
3be74084 871 int ret, is_data_pending;
6d805429 872 uint64_t id = msg.u.data_pending.session_id;
ca22feea 873
6d805429 874 DBG("UST consumer data pending command for id %" PRIu64, id);
ca22feea 875
3be74084 876 is_data_pending = consumer_data_pending(id);
ca22feea
DG
877
878 /* Send back returned value to session daemon */
3be74084
DG
879 ret = lttcomm_send_unix_sock(sock, &is_data_pending,
880 sizeof(is_data_pending));
ca22feea 881 if (ret < 0) {
3be74084 882 DBG("Error when sending the data pending ret code: %d", ret);
489f70e9 883 goto error_fatal;
ca22feea 884 }
f50f23d9
DG
885
886 /*
887 * No need to send back a status message since the data pending
888 * returned value is the response.
889 */
ca22feea 890 break;
53632229 891 }
ffe60014
DG
892 case LTTNG_CONSUMER_ASK_CHANNEL_CREATION:
893 {
894 int ret;
895 struct ustctl_consumer_channel_attr attr;
896
897 /* Create a plain object and reserve a channel key. */
898 channel = allocate_channel(msg.u.ask_channel.session_id,
899 msg.u.ask_channel.pathname, msg.u.ask_channel.name,
900 msg.u.ask_channel.uid, msg.u.ask_channel.gid,
901 msg.u.ask_channel.relayd_id, msg.u.ask_channel.key,
1624d5b7
JD
902 (enum lttng_event_output) msg.u.ask_channel.output,
903 msg.u.ask_channel.tracefile_size,
904 msg.u.ask_channel.tracefile_count);
ffe60014
DG
905 if (!channel) {
906 goto end_channel_error;
907 }
908
909 /* Build channel attributes from received message. */
910 attr.subbuf_size = msg.u.ask_channel.subbuf_size;
911 attr.num_subbuf = msg.u.ask_channel.num_subbuf;
912 attr.overwrite = msg.u.ask_channel.overwrite;
913 attr.switch_timer_interval = msg.u.ask_channel.switch_timer_interval;
914 attr.read_timer_interval = msg.u.ask_channel.read_timer_interval;
7972aab2 915 attr.chan_id = msg.u.ask_channel.chan_id;
ffe60014
DG
916 memcpy(attr.uuid, msg.u.ask_channel.uuid, sizeof(attr.uuid));
917
918 /* Translate the event output type to UST. */
919 switch (channel->output) {
920 case LTTNG_EVENT_SPLICE:
921 /* Splice not supported so fallback on mmap(). */
922 case LTTNG_EVENT_MMAP:
923 default:
924 attr.output = CONSUMER_CHANNEL_MMAP;
925 break;
926 };
927
928 /* Translate and save channel type. */
929 switch (msg.u.ask_channel.type) {
930 case LTTNG_UST_CHAN_PER_CPU:
931 channel->type = CONSUMER_CHANNEL_TYPE_DATA;
932 attr.type = LTTNG_UST_CHAN_PER_CPU;
8633d6e3
MD
933 /*
934 * Set refcount to 1 for owner. Below, we will
935 * pass ownership to the
936 * consumer_thread_channel_poll() thread.
937 */
938 channel->refcount = 1;
ffe60014
DG
939 break;
940 case LTTNG_UST_CHAN_METADATA:
941 channel->type = CONSUMER_CHANNEL_TYPE_METADATA;
942 attr.type = LTTNG_UST_CHAN_METADATA;
943 break;
944 default:
945 assert(0);
946 goto error_fatal;
947 };
948
949 ret = ask_channel(ctx, sock, channel, &attr);
950 if (ret < 0) {
951 goto end_channel_error;
952 }
953
fc643247
MD
954 if (msg.u.ask_channel.type == LTTNG_UST_CHAN_METADATA) {
955 ret = consumer_metadata_cache_allocate(channel);
956 if (ret < 0) {
957 ERR("Allocating metadata cache");
958 goto end_channel_error;
959 }
960 consumer_timer_switch_start(channel, attr.switch_timer_interval);
961 attr.switch_timer_interval = 0;
962 }
963
ffe60014
DG
964 /*
965 * Add the channel to the internal state AFTER all streams were created
966 * and successfully sent to session daemon. This way, all streams must
967 * be ready before this channel is visible to the threads.
fc643247
MD
968 * If add_channel succeeds, ownership of the channel is
969 * passed to consumer_thread_channel_poll().
ffe60014
DG
970 */
971 ret = add_channel(channel, ctx);
972 if (ret < 0) {
ea88ca2a
MD
973 if (msg.u.ask_channel.type == LTTNG_UST_CHAN_METADATA) {
974 if (channel->switch_timer_enabled == 1) {
975 consumer_timer_switch_stop(channel);
976 }
977 consumer_metadata_cache_destroy(channel);
978 }
ffe60014
DG
979 goto end_channel_error;
980 }
981
982 /*
983 * Channel and streams are now created. Inform the session daemon that
984 * everything went well and should wait to receive the channel and
985 * streams with ustctl API.
986 */
987 ret = consumer_send_status_channel(sock, channel);
988 if (ret < 0) {
989 /*
489f70e9 990 * There is probably a problem on the socket.
ffe60014 991 */
489f70e9 992 goto error_fatal;
ffe60014
DG
993 }
994
995 break;
996 }
997 case LTTNG_CONSUMER_GET_CHANNEL:
998 {
999 int ret, relayd_err = 0;
d88aee68 1000 uint64_t key = msg.u.get_channel.key;
ffe60014 1001 struct lttng_consumer_channel *channel;
ffe60014
DG
1002
1003 channel = consumer_find_channel(key);
1004 if (!channel) {
8fd623e0 1005 ERR("UST consumer get channel key %" PRIu64 " not found", key);
ffe60014
DG
1006 ret_code = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1007 goto end_msg_sessiond;
1008 }
1009
1010 /* Inform sessiond that we are about to send channel and streams. */
1011 ret = consumer_send_status_msg(sock, LTTNG_OK);
1012 if (ret < 0) {
1013 /* Somehow, the session daemon is not responding anymore. */
489f70e9 1014 goto error_fatal;
ffe60014
DG
1015 }
1016
1017 /* Send everything to sessiond. */
1018 ret = send_sessiond_channel(sock, channel, ctx, &relayd_err);
1019 if (ret < 0) {
1020 if (relayd_err) {
1021 /*
1022 * We were unable to send to the relayd the stream so avoid
1023 * sending back a fatal error to the thread since this is OK
1024 * and the consumer can continue its work.
1025 */
1026 ret_code = LTTNG_ERR_RELAYD_CONNECT_FAIL;
1027 goto end_msg_sessiond;
1028 }
1029 /*
1030 * The communicaton was broken hence there is a bad state between
1031 * the consumer and sessiond so stop everything.
1032 */
1033 goto error_fatal;
1034 }
1035
d88aee68
DG
1036 ret = send_streams_to_thread(channel, ctx);
1037 if (ret < 0) {
1038 /*
1039 * If we are unable to send the stream to the thread, there is
1040 * a big problem so just stop everything.
1041 */
1042 goto error_fatal;
ffe60014 1043 }
ffe60014
DG
1044 /* List MUST be empty after or else it could be reused. */
1045 assert(cds_list_empty(&channel->streams.head));
1046
d88aee68
DG
1047 goto end_msg_sessiond;
1048 }
1049 case LTTNG_CONSUMER_DESTROY_CHANNEL:
1050 {
1051 uint64_t key = msg.u.destroy_channel.key;
d88aee68 1052
a0cbdd2e
MD
1053 /*
1054 * Only called if streams have not been sent to stream
1055 * manager thread. However, channel has been sent to
1056 * channel manager thread.
1057 */
1058 notify_thread_del_channel(ctx, key);
d88aee68 1059 goto end_msg_sessiond;
ffe60014 1060 }
d88aee68
DG
1061 case LTTNG_CONSUMER_CLOSE_METADATA:
1062 {
1063 int ret;
1064
1065 ret = close_metadata(msg.u.close_metadata.key);
1066 if (ret != 0) {
1067 ret_code = ret;
1068 }
1069
1070 goto end_msg_sessiond;
1071 }
7972aab2
DG
1072 case LTTNG_CONSUMER_FLUSH_CHANNEL:
1073 {
1074 int ret;
1075
1076 ret = flush_channel(msg.u.flush_channel.key);
1077 if (ret != 0) {
1078 ret_code = ret;
1079 }
1080
1081 goto end_msg_sessiond;
1082 }
d88aee68 1083 case LTTNG_CONSUMER_PUSH_METADATA:
ffe60014
DG
1084 {
1085 int ret;
d88aee68 1086 uint64_t len = msg.u.push_metadata.len;
d88aee68 1087 uint64_t key = msg.u.push_metadata.key;
331744e3 1088 uint64_t offset = msg.u.push_metadata.target_offset;
ffe60014
DG
1089 struct lttng_consumer_channel *channel;
1090
8fd623e0
DG
1091 DBG("UST consumer push metadata key %" PRIu64 " of len %" PRIu64, key,
1092 len);
ffe60014
DG
1093
1094 channel = consumer_find_channel(key);
1095 if (!channel) {
8fd623e0 1096 ERR("UST consumer push metadata %" PRIu64 " not found", key);
ffe60014 1097 ret_code = LTTNG_ERR_UST_CHAN_NOT_FOUND;
4a2eb0ca 1098 goto end_msg_sessiond;
d88aee68
DG
1099 }
1100
1101 /* Tell session daemon we are ready to receive the metadata. */
ffe60014
DG
1102 ret = consumer_send_status_msg(sock, LTTNG_OK);
1103 if (ret < 0) {
1104 /* Somehow, the session daemon is not responding anymore. */
d88aee68
DG
1105 goto error_fatal;
1106 }
1107
1108 /* Wait for more data. */
1109 if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) {
489f70e9 1110 goto error_fatal;
d88aee68
DG
1111 }
1112
331744e3
JD
1113 ret = lttng_ustconsumer_recv_metadata(sock, key, offset,
1114 len, channel);
d88aee68 1115 if (ret < 0) {
331744e3 1116 /* error receiving from sessiond */
489f70e9 1117 goto error_fatal;
331744e3
JD
1118 } else {
1119 ret_code = ret;
d88aee68
DG
1120 goto end_msg_sessiond;
1121 }
d88aee68
DG
1122 }
1123 case LTTNG_CONSUMER_SETUP_METADATA:
1124 {
1125 int ret;
1126
1127 ret = setup_metadata(ctx, msg.u.setup_metadata.key);
1128 if (ret) {
1129 ret_code = ret;
1130 }
1131 goto end_msg_sessiond;
ffe60014 1132 }
3bd1e081
MD
1133 default:
1134 break;
1135 }
3f8e211f 1136
3bd1e081 1137end_nosignal:
b0b335c8 1138 rcu_read_unlock();
4cbc1a04
DG
1139
1140 /*
1141 * Return 1 to indicate success since the 0 value can be a socket
1142 * shutdown during the recv() or send() call.
1143 */
1144 return 1;
ffe60014
DG
1145
1146end_msg_sessiond:
1147 /*
1148 * The returned value here is not useful since either way we'll return 1 to
1149 * the caller because the session daemon socket management is done
1150 * elsewhere. Returning a negative code or 0 will shutdown the consumer.
1151 */
489f70e9
MD
1152 ret = consumer_send_status_msg(sock, ret_code);
1153 if (ret < 0) {
1154 goto error_fatal;
1155 }
ffe60014
DG
1156 rcu_read_unlock();
1157 return 1;
1158end_channel_error:
1159 if (channel) {
1160 /*
1161 * Free channel here since no one has a reference to it. We don't
1162 * free after that because a stream can store this pointer.
1163 */
1164 destroy_channel(channel);
1165 }
1166 /* We have to send a status channel message indicating an error. */
1167 ret = consumer_send_status_channel(sock, NULL);
1168 if (ret < 0) {
1169 /* Stop everything if session daemon can not be notified. */
1170 goto error_fatal;
1171 }
1172 rcu_read_unlock();
1173 return 1;
1174error_fatal:
1175 rcu_read_unlock();
1176 /* This will issue a consumer stop. */
1177 return -1;
3bd1e081
MD
1178}
1179
ffe60014
DG
1180/*
1181 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1182 * compiled out, we isolate it in this library.
1183 */
1184int lttng_ustctl_get_mmap_read_offset(struct lttng_consumer_stream *stream,
1185 unsigned long *off)
3bd1e081 1186{
ffe60014
DG
1187 assert(stream);
1188 assert(stream->ustream);
b5c5fc29 1189
ffe60014 1190 return ustctl_get_mmap_read_offset(stream->ustream, off);
3bd1e081
MD
1191}
1192
ffe60014
DG
1193/*
1194 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1195 * compiled out, we isolate it in this library.
1196 */
1197void *lttng_ustctl_get_mmap_base(struct lttng_consumer_stream *stream)
d056b477 1198{
ffe60014
DG
1199 assert(stream);
1200 assert(stream->ustream);
1201
1202 return ustctl_get_mmap_base(stream->ustream);
d056b477
MD
1203}
1204
ffe60014
DG
1205/*
1206 * Take a snapshot for a specific fd
1207 *
1208 * Returns 0 on success, < 0 on error
1209 */
1210int lttng_ustconsumer_take_snapshot(struct lttng_consumer_stream *stream)
3bd1e081 1211{
ffe60014
DG
1212 assert(stream);
1213 assert(stream->ustream);
1214
1215 return ustctl_snapshot(stream->ustream);
3bd1e081
MD
1216}
1217
ffe60014
DG
1218/*
1219 * Get the produced position
1220 *
1221 * Returns 0 on success, < 0 on error
1222 */
1223int lttng_ustconsumer_get_produced_snapshot(
1224 struct lttng_consumer_stream *stream, unsigned long *pos)
3bd1e081 1225{
ffe60014
DG
1226 assert(stream);
1227 assert(stream->ustream);
1228 assert(pos);
7a57cf92 1229
ffe60014
DG
1230 return ustctl_snapshot_get_produced(stream->ustream, pos);
1231}
7a57cf92 1232
ffe60014
DG
1233/*
1234 * Called when the stream signal the consumer that it has hang up.
1235 */
1236void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream *stream)
1237{
1238 assert(stream);
1239 assert(stream->ustream);
2c1dd183 1240
ffe60014
DG
1241 ustctl_flush_buffer(stream->ustream, 0);
1242 stream->hangup_flush_done = 1;
1243}
ee77a7b0 1244
ffe60014
DG
1245void lttng_ustconsumer_del_channel(struct lttng_consumer_channel *chan)
1246{
1247 assert(chan);
1248 assert(chan->uchan);
e316aad5 1249
ea88ca2a
MD
1250 if (chan->switch_timer_enabled == 1) {
1251 consumer_timer_switch_stop(chan);
1252 }
1253 consumer_metadata_cache_destroy(chan);
ffe60014 1254 ustctl_destroy_channel(chan->uchan);
3bd1e081
MD
1255}
1256
1257void lttng_ustconsumer_del_stream(struct lttng_consumer_stream *stream)
1258{
ffe60014
DG
1259 assert(stream);
1260 assert(stream->ustream);
d41f73b7 1261
ea88ca2a
MD
1262 if (stream->chan->switch_timer_enabled == 1) {
1263 consumer_timer_switch_stop(stream->chan);
1264 }
ffe60014
DG
1265 ustctl_destroy_stream(stream->ustream);
1266}
d41f73b7
MD
1267
1268int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream *stream,
1269 struct lttng_consumer_local_data *ctx)
1270{
1d4dfdef 1271 unsigned long len, subbuf_size, padding;
d41f73b7
MD
1272 int err;
1273 long ret = 0;
d41f73b7 1274 char dummy;
ffe60014
DG
1275 struct ustctl_consumer_stream *ustream;
1276
1277 assert(stream);
1278 assert(stream->ustream);
1279 assert(ctx);
d41f73b7 1280
ffe60014
DG
1281 DBG2("In UST read_subbuffer (wait_fd: %d, name: %s)", stream->wait_fd,
1282 stream->name);
1283
1284 /* Ease our life for what's next. */
1285 ustream = stream->ustream;
d41f73b7
MD
1286
1287 /* We can consume the 1 byte written into the wait_fd by UST */
effcf122 1288 if (!stream->hangup_flush_done) {
c617c0c6
MD
1289 ssize_t readlen;
1290
effcf122
MD
1291 do {
1292 readlen = read(stream->wait_fd, &dummy, 1);
87dc6a9c 1293 } while (readlen == -1 && errno == EINTR);
effcf122
MD
1294 if (readlen == -1) {
1295 ret = readlen;
1296 goto end;
1297 }
d41f73b7
MD
1298 }
1299
d41f73b7 1300 /* Get the next subbuffer */
ffe60014 1301 err = ustctl_get_next_subbuf(ustream);
d41f73b7 1302 if (err != 0) {
1d4dfdef 1303 ret = err; /* ustctl_get_next_subbuf returns negative, caller expect positive. */
d41f73b7
MD
1304 /*
1305 * This is a debug message even for single-threaded consumer,
1306 * because poll() have more relaxed criterions than get subbuf,
1307 * so get_subbuf may fail for short race windows where poll()
1308 * would issue wakeups.
1309 */
1310 DBG("Reserving sub buffer failed (everything is normal, "
ffe60014 1311 "it is due to concurrency) [ret: %d]", err);
d41f73b7
MD
1312 goto end;
1313 }
ffe60014 1314 assert(stream->chan->output == CONSUMER_CHANNEL_MMAP);
1d4dfdef 1315 /* Get the full padded subbuffer size */
ffe60014 1316 err = ustctl_get_padded_subbuf_size(ustream, &len);
effcf122 1317 assert(err == 0);
1d4dfdef
DG
1318
1319 /* Get subbuffer data size (without padding) */
ffe60014 1320 err = ustctl_get_subbuf_size(ustream, &subbuf_size);
1d4dfdef
DG
1321 assert(err == 0);
1322
1323 /* Make sure we don't get a subbuffer size bigger than the padded */
1324 assert(len >= subbuf_size);
1325
1326 padding = len - subbuf_size;
d41f73b7 1327 /* write the subbuffer to the tracefile */
1d4dfdef 1328 ret = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, subbuf_size, padding);
91dfef6e
DG
1329 /*
1330 * The mmap operation should write subbuf_size amount of data when network
1331 * streaming or the full padding (len) size when we are _not_ streaming.
1332 */
d88aee68
DG
1333 if ((ret != subbuf_size && stream->net_seq_idx != (uint64_t) -1ULL) ||
1334 (ret != len && stream->net_seq_idx == (uint64_t) -1ULL)) {
d41f73b7 1335 /*
91dfef6e 1336 * Display the error but continue processing to try to release the
c5c45efa
DG
1337 * subbuffer. This is a DBG statement since any unexpected kill or
1338 * signal, the application gets unregistered, relayd gets closed or
1339 * anything that affects the buffer lifetime will trigger this error.
1340 * So, for the sake of the user, don't print this error since it can
1341 * happen and it is OK with the code flow.
d41f73b7 1342 */
c5c45efa 1343 DBG("Error writing to tracefile "
8fd623e0 1344 "(ret: %ld != len: %lu != subbuf_size: %lu)",
91dfef6e 1345 ret, len, subbuf_size);
d41f73b7 1346 }
ffe60014 1347 err = ustctl_put_next_subbuf(ustream);
effcf122 1348 assert(err == 0);
331744e3 1349
d41f73b7
MD
1350end:
1351 return ret;
1352}
1353
ffe60014
DG
1354/*
1355 * Called when a stream is created.
fe4477ee
JD
1356 *
1357 * Return 0 on success or else a negative value.
ffe60014 1358 */
d41f73b7
MD
1359int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream *stream)
1360{
fe4477ee
JD
1361 int ret;
1362
1363 /* Don't create anything if this is set for streaming. */
1364 if (stream->net_seq_idx == (uint64_t) -1ULL) {
1365 ret = utils_create_stream_file(stream->chan->pathname, stream->name,
1366 stream->chan->tracefile_size, stream->tracefile_count_current,
1367 stream->uid, stream->gid);
1368 if (ret < 0) {
1369 goto error;
1370 }
1371 stream->out_fd = ret;
1372 stream->tracefile_size_current = 0;
1373 }
1374 ret = 0;
1375
1376error:
1377 return ret;
d41f73b7 1378}
ca22feea
DG
1379
1380/*
1381 * Check if data is still being extracted from the buffers for a specific
4e9a4686
DG
1382 * stream. Consumer data lock MUST be acquired before calling this function
1383 * and the stream lock.
ca22feea 1384 *
6d805429 1385 * Return 1 if the traced data are still getting read else 0 meaning that the
ca22feea
DG
1386 * data is available for trace viewer reading.
1387 */
6d805429 1388int lttng_ustconsumer_data_pending(struct lttng_consumer_stream *stream)
ca22feea
DG
1389{
1390 int ret;
1391
1392 assert(stream);
ffe60014 1393 assert(stream->ustream);
ca22feea 1394
6d805429 1395 DBG("UST consumer checking data pending");
c8f59ee5 1396
ffe60014 1397 ret = ustctl_get_next_subbuf(stream->ustream);
ca22feea
DG
1398 if (ret == 0) {
1399 /* There is still data so let's put back this subbuffer. */
ffe60014 1400 ret = ustctl_put_subbuf(stream->ustream);
ca22feea 1401 assert(ret == 0);
6d805429 1402 ret = 1; /* Data is pending */
4e9a4686 1403 goto end;
ca22feea
DG
1404 }
1405
6d805429
DG
1406 /* Data is NOT pending so ready to be read. */
1407 ret = 0;
ca22feea 1408
6efae65e
DG
1409end:
1410 return ret;
ca22feea 1411}
d88aee68
DG
1412
1413/*
1414 * Close every metadata stream wait fd of the metadata hash table. This
1415 * function MUST be used very carefully so not to run into a race between the
1416 * metadata thread handling streams and this function closing their wait fd.
1417 *
1418 * For UST, this is used when the session daemon hangs up. Its the metadata
1419 * producer so calling this is safe because we are assured that no state change
1420 * can occur in the metadata thread for the streams in the hash table.
1421 */
1422void lttng_ustconsumer_close_metadata(struct lttng_ht *metadata_ht)
1423{
1424 int ret;
1425 struct lttng_ht_iter iter;
1426 struct lttng_consumer_stream *stream;
1427
1428 assert(metadata_ht);
1429 assert(metadata_ht->ht);
1430
1431 DBG("UST consumer closing all metadata streams");
1432
1433 rcu_read_lock();
1434 cds_lfht_for_each_entry(metadata_ht->ht, &iter.iter, stream,
1435 node.node) {
1436 int fd = stream->wait_fd;
1437
1438 /*
1439 * Whatever happens here we have to continue to try to close every
1440 * streams. Let's report at least the error on failure.
1441 */
1442 ret = ustctl_stream_close_wakeup_fd(stream->ustream);
1443 if (ret) {
1444 ERR("Unable to close metadata stream fd %d ret %d", fd, ret);
1445 }
1446 DBG("Metadata wait fd %d closed", fd);
1447 }
1448 rcu_read_unlock();
1449}
d8ef542d
MD
1450
1451void lttng_ustconsumer_close_stream_wakeup(struct lttng_consumer_stream *stream)
1452{
1453 int ret;
1454
1455 ret = ustctl_stream_close_wakeup_fd(stream->ustream);
1456 if (ret < 0) {
1457 ERR("Unable to close wakeup fd");
1458 }
1459}
331744e3
JD
1460
1461int lttng_ustconsumer_request_metadata(struct lttng_consumer_local_data *ctx,
1462 struct lttng_consumer_channel *channel)
1463{
1464 struct lttcomm_metadata_request_msg request;
1465 struct lttcomm_consumer_msg msg;
1466 enum lttng_error_code ret_code = LTTNG_OK;
1467 uint64_t len, key, offset;
1468 int ret;
1469
1470 assert(channel);
1471 assert(channel->metadata_cache);
1472
1473 /* send the metadata request to sessiond */
1474 switch (consumer_data.type) {
1475 case LTTNG_CONSUMER64_UST:
1476 request.bits_per_long = 64;
1477 break;
1478 case LTTNG_CONSUMER32_UST:
1479 request.bits_per_long = 32;
1480 break;
1481 default:
1482 request.bits_per_long = 0;
1483 break;
1484 }
1485
1486 request.session_id = channel->session_id;
1487 request.uid = channel->uid;
1488 request.key = channel->key;
1489 DBG("Sending metadata request to sessiond, session %" PRIu64,
1490 channel->session_id);
1491
1492 ret = lttcomm_send_unix_sock(ctx->consumer_metadata_socket, &request,
1493 sizeof(request));
1494 if (ret < 0) {
1495 ERR("Asking metadata to sessiond");
1496 goto end;
1497 }
1498
1499 /* Receive the metadata from sessiond */
1500 ret = lttcomm_recv_unix_sock(ctx->consumer_metadata_socket, &msg,
1501 sizeof(msg));
1502 if (ret != sizeof(msg)) {
8fd623e0 1503 DBG("Consumer received unexpected message size %d (expects %zu)",
331744e3
JD
1504 ret, sizeof(msg));
1505 lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_ERROR_RECV_CMD);
1506 /*
1507 * The ret value might 0 meaning an orderly shutdown but this is ok
1508 * since the caller handles this.
1509 */
1510 goto end;
1511 }
1512
1513 if (msg.cmd_type == LTTNG_ERR_UND) {
1514 /* No registry found */
1515 (void) consumer_send_status_msg(ctx->consumer_metadata_socket,
1516 ret_code);
1517 ret = 0;
1518 goto end;
1519 } else if (msg.cmd_type != LTTNG_CONSUMER_PUSH_METADATA) {
1520 ERR("Unexpected cmd_type received %d", msg.cmd_type);
1521 ret = -1;
1522 goto end;
1523 }
1524
1525 len = msg.u.push_metadata.len;
1526 key = msg.u.push_metadata.key;
1527 offset = msg.u.push_metadata.target_offset;
1528
1529 assert(key == channel->key);
1530 if (len == 0) {
1531 DBG("No new metadata to receive for key %" PRIu64, key);
1532 }
1533
1534 /* Tell session daemon we are ready to receive the metadata. */
1535 ret = consumer_send_status_msg(ctx->consumer_metadata_socket,
1536 LTTNG_OK);
1537 if (ret < 0 || len == 0) {
1538 /*
1539 * Somehow, the session daemon is not responding anymore or there is
1540 * nothing to receive.
1541 */
1542 goto end;
1543 }
1544
1545 ret_code = lttng_ustconsumer_recv_metadata(ctx->consumer_metadata_socket,
1546 key, offset, len, channel);
1547 (void) consumer_send_status_msg(ctx->consumer_metadata_socket, ret_code);
1548 ret = 0;
1549
1550end:
1551 return ret;
1552}
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