src/common/consumer/consumer-stream.c

   1 /*
   2  * Copyright (C) 2011 Julien Desfossez <julien.desfossez@polymtl.ca>
   3  * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   4  * Copyright (C) 2013 David Goulet <dgoulet@efficios.com>
   5  *
   6  * SPDX-License-Identifier: GPL-2.0-only
   7  *
   8  */
   9
  10 #define _LGPL_SOURCE
  11 #include <assert.h>
  12 #include <inttypes.h>
  13 #include <sys/mman.h>
  14 #include <unistd.h>
  15
  16 #include <common/common.h>
  17 #include <common/index/index.h>
  18 #include <common/kernel-consumer/kernel-consumer.h>
  19 #include <common/relayd/relayd.h>
  20 #include <common/ust-consumer/ust-consumer.h>
  21 #include <common/utils.h>
  22 #include <common/consumer/consumer.h>
  23 #include <common/consumer/consumer-timer.h>
  24 #include <common/consumer/metadata-bucket.h>
  25
  26 #include "consumer-stream.h"
  27
  28 /*
  29  * RCU call to free stream. MUST only be used with call_rcu().
  30  */
  31 static void free_stream_rcu(struct rcu_head *head)
  32 {
  33         struct lttng_ht_node_u64 *node =
  34                 caa_container_of(head, struct lttng_ht_node_u64, head);
  35         struct lttng_consumer_stream *stream =
  36                 caa_container_of(node, struct lttng_consumer_stream, node);
  37
  38         pthread_mutex_destroy(&stream->lock);
  39         free(stream);
  40 }
  41
  42 static void consumer_stream_data_lock_all(struct lttng_consumer_stream *stream)
  43 {
  44         pthread_mutex_lock(&stream->chan->lock);
  45         pthread_mutex_lock(&stream->lock);
  46 }
  47
  48 static void consumer_stream_data_unlock_all(struct lttng_consumer_stream *stream)
  49 {
  50         pthread_mutex_unlock(&stream->lock);
  51         pthread_mutex_unlock(&stream->chan->lock);
  52 }
  53
  54 static void consumer_stream_metadata_lock_all(struct lttng_consumer_stream *stream)
  55 {
  56         consumer_stream_data_lock_all(stream);
  57         pthread_mutex_lock(&stream->metadata_rdv_lock);
  58 }
  59
  60 static void consumer_stream_metadata_unlock_all(struct lttng_consumer_stream *stream)
  61 {
  62         pthread_mutex_unlock(&stream->metadata_rdv_lock);
  63         consumer_stream_data_unlock_all(stream);
  64 }
  65
  66 /* Only used for data streams. */
  67 static int consumer_stream_update_stats(struct lttng_consumer_stream *stream,
  68                 const struct stream_subbuffer *subbuf)
  69 {
  70         int ret = 0;
  71         uint64_t sequence_number;
  72         const uint64_t discarded_events = subbuf->info.data.events_discarded;
  73
  74         if (!subbuf->info.data.sequence_number.is_set) {
  75                 /* Command not supported by the tracer. */
  76                 sequence_number = -1ULL;
  77                 stream->sequence_number_unavailable = true;
  78         } else {
  79                 sequence_number = subbuf->info.data.sequence_number.value;
  80         }
  81
  82         /*
  83          * Start the sequence when we extract the first packet in case we don't
  84          * start at 0 (for example if a consumer is not connected to the
  85          * session immediately after the beginning).
  86          */
  87         if (stream->last_sequence_number == -1ULL) {
  88                 stream->last_sequence_number = sequence_number;
  89         } else if (sequence_number > stream->last_sequence_number) {
  90                 stream->chan->lost_packets += sequence_number -
  91                                 stream->last_sequence_number - 1;
  92         } else {
  93                 /* seq <= last_sequence_number */
  94                 ERR("Sequence number inconsistent : prev = %" PRIu64
  95                     ", current = %" PRIu64,
  96                                 stream->last_sequence_number, sequence_number);
  97                 ret = -1;
  98                 goto end;
  99         }
 100         stream->last_sequence_number = sequence_number;
 101
 102         if (discarded_events < stream->last_discarded_events) {
 103                 /*
 104                  * Overflow has occurred. We assume only one wrap-around
 105                  * has occurred.
 106                  */
 107                 stream->chan->discarded_events +=
 108                                 (1ULL << (CAA_BITS_PER_LONG - 1)) -
 109                                 stream->last_discarded_events +
 110                                 discarded_events;
 111         } else {
 112                 stream->chan->discarded_events += discarded_events -
 113                                                   stream->last_discarded_events;
 114         }
 115         stream->last_discarded_events = discarded_events;
 116         ret = 0;
 117
 118 end:
 119         return ret;
 120 }
 121
 122 static
 123 void ctf_packet_index_populate(struct ctf_packet_index *index,
 124                 off_t offset, const struct stream_subbuffer *subbuffer)
 125 {
 126         *index = (typeof(*index)){
 127                 .offset = htobe64(offset),
 128                 .packet_size = htobe64(subbuffer->info.data.packet_size),
 129                 .content_size = htobe64(subbuffer->info.data.content_size),
 130                 .timestamp_begin = htobe64(
 131                                 subbuffer->info.data.timestamp_begin),
 132                 .timestamp_end = htobe64(
 133                                 subbuffer->info.data.timestamp_end),
 134                 .events_discarded = htobe64(
 135                                 subbuffer->info.data.events_discarded),
 136                 .stream_id = htobe64(subbuffer->info.data.stream_id),
 137                 .stream_instance_id = htobe64(
 138                                 subbuffer->info.data.stream_instance_id.is_set ?
 139                                 subbuffer->info.data.stream_instance_id.value : -1ULL),
 140                 .packet_seq_num = htobe64(
 141                                 subbuffer->info.data.sequence_number.is_set ?
 142                                 subbuffer->info.data.sequence_number.value : -1ULL),
 143         };
 144 }
 145
 146 static ssize_t consumer_stream_consume_mmap(
 147                 struct lttng_consumer_local_data *ctx,
 148                 struct lttng_consumer_stream *stream,
 149                 const struct stream_subbuffer *subbuffer)
 150 {
 151         const unsigned long padding_size =
 152                         subbuffer->info.data.padded_subbuf_size -
 153                         subbuffer->info.data.subbuf_size;
 154
 155         return lttng_consumer_on_read_subbuffer_mmap(
 156                         stream, &subbuffer->buffer.buffer, padding_size);
 157 }
 158
 159 static ssize_t consumer_stream_consume_splice(
 160                 struct lttng_consumer_local_data *ctx,
 161                 struct lttng_consumer_stream *stream,
 162                 const struct stream_subbuffer *subbuffer)
 163 {
 164         return lttng_consumer_on_read_subbuffer_splice(ctx, stream,
 165                         subbuffer->info.data.padded_subbuf_size, 0);
 166 }
 167
 168 static int consumer_stream_send_index(
 169                 struct lttng_consumer_stream *stream,
 170                 const struct stream_subbuffer *subbuffer,
 171                 struct lttng_consumer_local_data *ctx)
 172 {
 173         off_t packet_offset = 0;
 174         struct ctf_packet_index index = {};
 175
 176         /*
 177          * This is called after consuming the sub-buffer; substract the
 178          * effect this sub-buffer from the offset.
 179          */
 180         if (stream->net_seq_idx == (uint64_t) -1ULL) {
 181                 packet_offset = stream->out_fd_offset -
 182                                 subbuffer->info.data.padded_subbuf_size;
 183         }
 184
 185         ctf_packet_index_populate(&index, packet_offset, subbuffer);
 186         return consumer_stream_write_index(stream, &index);
 187 }
 188
 189 /*
 190  * Actually do the metadata sync using the given metadata stream.
 191  *
 192  * Return 0 on success else a negative value. ENODATA can be returned also
 193  * indicating that there is no metadata available for that stream.
 194  */
 195 static int do_sync_metadata(struct lttng_consumer_stream *metadata,
 196                 struct lttng_consumer_local_data *ctx)
 197 {
 198         int ret;
 199         enum sync_metadata_status status;
 200
 201         assert(metadata);
 202         assert(metadata->metadata_flag);
 203         assert(ctx);
 204
 205         /*
 206          * In UST, since we have to write the metadata from the cache packet
 207          * by packet, we might need to start this procedure multiple times
 208          * until all the metadata from the cache has been extracted.
 209          */
 210         do {
 211                 /*
 212                  * Steps :
 213                  * - Lock the metadata stream
 214                  * - Check if metadata stream node was deleted before locking.
 215                  *   - if yes, release and return success
 216                  * - Check if new metadata is ready (flush + snapshot pos)
 217                  * - If nothing : release and return.
 218                  * - Lock the metadata_rdv_lock
 219                  * - Unlock the metadata stream
 220                  * - cond_wait on metadata_rdv to wait the wakeup from the
 221                  *   metadata thread
 222                  * - Unlock the metadata_rdv_lock
 223                  */
 224                 pthread_mutex_lock(&metadata->lock);
 225
 226                 /*
 227                  * There is a possibility that we were able to acquire a reference on the
 228                  * stream from the RCU hash table but between then and now, the node might
 229                  * have been deleted just before the lock is acquired. Thus, after locking,
 230                  * we make sure the metadata node has not been deleted which means that the
 231                  * buffers are closed.
 232                  *
 233                  * In that case, there is no need to sync the metadata hence returning a
 234                  * success return code.
 235                  */
 236                 ret = cds_lfht_is_node_deleted(&metadata->node.node);
 237                 if (ret) {
 238                         ret = 0;
 239                         goto end_unlock_mutex;
 240                 }
 241
 242                 switch (ctx->type) {
 243                 case LTTNG_CONSUMER_KERNEL:
 244                         /*
 245                          * Empty the metadata cache and flush the current stream.
 246                          */
 247                         status = lttng_kconsumer_sync_metadata(metadata);
 248                         break;
 249                 case LTTNG_CONSUMER32_UST:
 250                 case LTTNG_CONSUMER64_UST:
 251                         /*
 252                          * Ask the sessiond if we have new metadata waiting and update the
 253                          * consumer metadata cache.
 254                          */
 255                         status = lttng_ustconsumer_sync_metadata(ctx, metadata);
 256                         break;
 257                 default:
 258                         abort();
 259                 }
 260
 261                 switch (status) {
 262                 case SYNC_METADATA_STATUS_NEW_DATA:
 263                         break;
 264                 case SYNC_METADATA_STATUS_NO_DATA:
 265                         ret = 0;
 266                         goto end_unlock_mutex;
 267                 case SYNC_METADATA_STATUS_ERROR:
 268                         ret = -1;
 269                         goto end_unlock_mutex;
 270                 default:
 271                         abort();
 272                 }
 273
 274                 /*
 275                  * At this point, new metadata have been flushed, so we wait on the
 276                  * rendez-vous point for the metadata thread to wake us up when it
 277                  * finishes consuming the metadata and continue execution.
 278                  */
 279
 280                 pthread_mutex_lock(&metadata->metadata_rdv_lock);
 281
 282                 /*
 283                  * Release metadata stream lock so the metadata thread can process it.
 284                  */
 285                 pthread_mutex_unlock(&metadata->lock);
 286
 287                 /*
 288                  * Wait on the rendez-vous point. Once woken up, it means the metadata was
 289                  * consumed and thus synchronization is achieved.
 290                  */
 291                 pthread_cond_wait(&metadata->metadata_rdv, &metadata->metadata_rdv_lock);
 292                 pthread_mutex_unlock(&metadata->metadata_rdv_lock);
 293         } while (status == SYNC_METADATA_STATUS_NEW_DATA);
 294
 295         /* Success */
 296         return 0;
 297
 298 end_unlock_mutex:
 299         pthread_mutex_unlock(&metadata->lock);
 300         return ret;
 301 }
 302
 303 /*
 304  * Synchronize the metadata using a given session ID. A successful acquisition
 305  * of a metadata stream will trigger a request to the session daemon and a
 306  * snapshot so the metadata thread can consume it.
 307  *
 308  * This function call is a rendez-vous point between the metadata thread and
 309  * the data thread.
 310  *
 311  * Return 0 on success or else a negative value.
 312  */
 313 int consumer_stream_sync_metadata(struct lttng_consumer_local_data *ctx,
 314                 uint64_t session_id)
 315 {
 316         int ret;
 317         struct lttng_consumer_stream *stream = NULL;
 318         struct lttng_ht_iter iter;
 319         struct lttng_ht *ht;
 320
 321         assert(ctx);
 322
 323         /* Ease our life a bit. */
 324         ht = consumer_data.stream_list_ht;
 325
 326         rcu_read_lock();
 327
 328         /* Search the metadata associated with the session id of the given stream. */
 329
 330         cds_lfht_for_each_entry_duplicate(ht->ht,
 331                         ht->hash_fct(&session_id, lttng_ht_seed), ht->match_fct,
 332                         &session_id, &iter.iter, stream, node_session_id.node) {
 333                 if (!stream->metadata_flag) {
 334                         continue;
 335                 }
 336
 337                 ret = do_sync_metadata(stream, ctx);
 338                 if (ret < 0) {
 339                         goto end;
 340                 }
 341         }
 342
 343         /*
 344          * Force return code to 0 (success) since ret might be ENODATA for instance
 345          * which is not an error but rather that we should come back.
 346          */
 347         ret = 0;
 348
 349 end:
 350         rcu_read_unlock();
 351         return ret;
 352 }
 353
 354 static int consumer_stream_sync_metadata_index(
 355                 struct lttng_consumer_stream *stream,
 356                 const struct stream_subbuffer *subbuffer,
 357                 struct lttng_consumer_local_data *ctx)
 358 {
 359         int ret;
 360
 361         /* Block until all the metadata is sent. */
 362         pthread_mutex_lock(&stream->metadata_timer_lock);
 363         assert(!stream->missed_metadata_flush);
 364         stream->waiting_on_metadata = true;
 365         pthread_mutex_unlock(&stream->metadata_timer_lock);
 366
 367         ret = consumer_stream_sync_metadata(ctx, stream->session_id);
 368
 369         pthread_mutex_lock(&stream->metadata_timer_lock);
 370         stream->waiting_on_metadata = false;
 371         if (stream->missed_metadata_flush) {
 372                 stream->missed_metadata_flush = false;
 373                 pthread_mutex_unlock(&stream->metadata_timer_lock);
 374                 (void) stream->read_subbuffer_ops.send_live_beacon(stream);
 375         } else {
 376                 pthread_mutex_unlock(&stream->metadata_timer_lock);
 377         }
 378         if (ret < 0) {
 379                 goto end;
 380         }
 381
 382         ret = consumer_stream_send_index(stream, subbuffer, ctx);
 383 end:
 384         return ret;
 385 }
 386
 387 /*
 388  * Check if the local version of the metadata stream matches with the version
 389  * of the metadata stream in the kernel. If it was updated, set the reset flag
 390  * on the stream.
 391  */
 392 static
 393 int metadata_stream_check_version(struct lttng_consumer_stream *stream,
 394         const struct stream_subbuffer *subbuffer)
 395 {
 396         if (stream->metadata_version == subbuffer->info.metadata.version) {
 397                 goto end;
 398         }
 399
 400         DBG("New metadata version detected");
 401         consumer_stream_metadata_set_version(stream,
 402                         subbuffer->info.metadata.version);
 403
 404         if (stream->read_subbuffer_ops.reset_metadata) {
 405                 stream->read_subbuffer_ops.reset_metadata(stream);
 406         }
 407
 408 end:
 409         return 0;
 410 }
 411
 412 struct lttng_consumer_stream *consumer_stream_create(
 413                 struct lttng_consumer_channel *channel,
 414                 uint64_t channel_key,
 415                 uint64_t stream_key,
 416                 const char *channel_name,
 417                 uint64_t relayd_id,
 418                 uint64_t session_id,
 419                 struct lttng_trace_chunk *trace_chunk,
 420                 int cpu,
 421                 int *alloc_ret,
 422                 enum consumer_channel_type type,
 423                 unsigned int monitor)
 424 {
 425         int ret;
 426         struct lttng_consumer_stream *stream;
 427
 428         stream = zmalloc(sizeof(*stream));
 429         if (stream == NULL) {
 430                 PERROR("malloc struct lttng_consumer_stream");
 431                 ret = -ENOMEM;
 432                 goto end;
 433         }
 434
 435         if (trace_chunk && !lttng_trace_chunk_get(trace_chunk)) {
 436                 ERR("Failed to acquire trace chunk reference during the creation of a stream");
 437                 ret = -1;
 438                 goto error;
 439         }
 440
 441         rcu_read_lock();
 442         stream->chan = channel;
 443         stream->key = stream_key;
 444         stream->trace_chunk = trace_chunk;
 445         stream->out_fd = -1;
 446         stream->out_fd_offset = 0;
 447         stream->output_written = 0;
 448         stream->net_seq_idx = relayd_id;
 449         stream->session_id = session_id;
 450         stream->monitor = monitor;
 451         stream->endpoint_status = CONSUMER_ENDPOINT_ACTIVE;
 452         stream->index_file = NULL;
 453         stream->last_sequence_number = -1ULL;
 454         stream->rotate_position = -1ULL;
 455         pthread_mutex_init(&stream->lock, NULL);
 456         pthread_mutex_init(&stream->metadata_timer_lock, NULL);
 457
 458         /* If channel is the metadata, flag this stream as metadata. */
 459         if (type == CONSUMER_CHANNEL_TYPE_METADATA) {
 460                 stream->metadata_flag = 1;
 461                 /* Metadata is flat out. */
 462                 strncpy(stream->name, DEFAULT_METADATA_NAME, sizeof(stream->name));
 463                 /* Live rendez-vous point. */
 464                 pthread_cond_init(&stream->metadata_rdv, NULL);
 465                 pthread_mutex_init(&stream->metadata_rdv_lock, NULL);
 466         } else {
 467                 /* Format stream name to <channel_name>_<cpu_number> */
 468                 ret = snprintf(stream->name, sizeof(stream->name), "%s_%d",
 469                                 channel_name, cpu);
 470                 if (ret < 0) {
 471                         PERROR("snprintf stream name");
 472                         goto error;
 473                 }
 474         }
 475
 476         switch (channel->output) {
 477         case CONSUMER_CHANNEL_SPLICE:
 478                 stream->output = LTTNG_EVENT_SPLICE;
 479                 ret = utils_create_pipe(stream->splice_pipe);
 480                 if (ret < 0) {
 481                         goto error;
 482                 }
 483                 break;
 484         case CONSUMER_CHANNEL_MMAP:
 485                 stream->output = LTTNG_EVENT_MMAP;
 486                 break;
 487         default:
 488                 abort();
 489         }
 490
 491         /* Key is always the wait_fd for streams. */
 492         lttng_ht_node_init_u64(&stream->node, stream->key);
 493
 494         /* Init node per channel id key */
 495         lttng_ht_node_init_u64(&stream->node_channel_id, channel_key);
 496
 497         /* Init session id node with the stream session id */
 498         lttng_ht_node_init_u64(&stream->node_session_id, stream->session_id);
 499
 500         DBG3("Allocated stream %s (key %" PRIu64 ", chan_key %" PRIu64
 501                         " relayd_id %" PRIu64 ", session_id %" PRIu64,
 502                         stream->name, stream->key, channel_key,
 503                         stream->net_seq_idx, stream->session_id);
 504
 505         rcu_read_unlock();
 506
 507         if (type == CONSUMER_CHANNEL_TYPE_METADATA) {
 508                 stream->read_subbuffer_ops.lock =
 509                                 consumer_stream_metadata_lock_all;
 510                 stream->read_subbuffer_ops.unlock =
 511                                 consumer_stream_metadata_unlock_all;
 512                 stream->read_subbuffer_ops.pre_consume_subbuffer =
 513                                 metadata_stream_check_version;
 514         } else {
 515                 stream->read_subbuffer_ops.lock = consumer_stream_data_lock_all;
 516                 stream->read_subbuffer_ops.unlock =
 517                                 consumer_stream_data_unlock_all;
 518                 stream->read_subbuffer_ops.pre_consume_subbuffer =
 519                                 consumer_stream_update_stats;
 520                 if (channel->is_live) {
 521                         stream->read_subbuffer_ops.post_consume =
 522                                         consumer_stream_sync_metadata_index;
 523                 } else {
 524                         stream->read_subbuffer_ops.post_consume =
 525                                         consumer_stream_send_index;
 526                 }
 527         }
 528
 529         if (channel->output == CONSUMER_CHANNEL_MMAP) {
 530                 stream->read_subbuffer_ops.consume_subbuffer =
 531                                 consumer_stream_consume_mmap;
 532         } else {
 533                 stream->read_subbuffer_ops.consume_subbuffer =
 534                                 consumer_stream_consume_splice;
 535         }
 536
 537         return stream;
 538
 539 error:
 540         rcu_read_unlock();
 541         lttng_trace_chunk_put(stream->trace_chunk);
 542         free(stream);
 543 end:
 544         if (alloc_ret) {
 545                 *alloc_ret = ret;
 546         }
 547         return NULL;
 548 }
 549
 550 /*
 551  * Close stream on the relayd side. This call can destroy a relayd if the
 552  * conditions are met.
 553  *
 554  * A RCU read side lock MUST be acquired if the relayd object was looked up in
 555  * a hash table before calling this.
 556  */
 557 void consumer_stream_relayd_close(struct lttng_consumer_stream *stream,
 558                 struct consumer_relayd_sock_pair *relayd)
 559 {
 560         int ret;
 561
 562         assert(stream);
 563         assert(relayd);
 564
 565         if (stream->sent_to_relayd) {
 566                 uatomic_dec(&relayd->refcount);
 567                 assert(uatomic_read(&relayd->refcount) >= 0);
 568         }
 569
 570         /* Closing streams requires to lock the control socket. */
 571         pthread_mutex_lock(&relayd->ctrl_sock_mutex);
 572         ret = relayd_send_close_stream(&relayd->control_sock,
 573                         stream->relayd_stream_id,
 574                         stream->next_net_seq_num - 1);
 575         pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
 576         if (ret < 0) {
 577                 ERR("Relayd send close stream failed. Cleaning up relayd %" PRIu64 ".", relayd->net_seq_idx);
 578                 lttng_consumer_cleanup_relayd(relayd);
 579         }
 580
 581         /* Both conditions are met, we destroy the relayd. */
 582         if (uatomic_read(&relayd->refcount) == 0 &&
 583                         uatomic_read(&relayd->destroy_flag)) {
 584                 consumer_destroy_relayd(relayd);
 585         }
 586         stream->net_seq_idx = (uint64_t) -1ULL;
 587         stream->sent_to_relayd = 0;
 588 }
 589
 590 /*
 591  * Close stream's file descriptors and, if needed, close stream also on the
 592  * relayd side.
 593  *
 594  * The consumer data lock MUST be acquired.
 595  * The stream lock MUST be acquired.
 596  */
 597 void consumer_stream_close(struct lttng_consumer_stream *stream)
 598 {
 599         int ret;
 600         struct consumer_relayd_sock_pair *relayd;
 601
 602         assert(stream);
 603
 604         switch (consumer_data.type) {
 605         case LTTNG_CONSUMER_KERNEL:
 606                 if (stream->mmap_base != NULL) {
 607                         ret = munmap(stream->mmap_base, stream->mmap_len);
 608                         if (ret != 0) {
 609                                 PERROR("munmap");
 610                         }
 611                 }
 612
 613                 if (stream->wait_fd >= 0) {
 614                         ret = close(stream->wait_fd);
 615                         if (ret) {
 616                                 PERROR("close");
 617                         }
 618                         stream->wait_fd = -1;
 619                 }
 620                 if (stream->chan->output == CONSUMER_CHANNEL_SPLICE) {
 621                         utils_close_pipe(stream->splice_pipe);
 622                 }
 623                 break;
 624         case LTTNG_CONSUMER32_UST:
 625         case LTTNG_CONSUMER64_UST:
 626         {
 627                 /*
 628                  * Special case for the metadata since the wait fd is an internal pipe
 629                  * polled in the metadata thread.
 630                  */
 631                 if (stream->metadata_flag && stream->chan->monitor) {
 632                         int rpipe = stream->ust_metadata_poll_pipe[0];
 633
 634                         /*
 635                          * This will stop the channel timer if one and close the write side
 636                          * of the metadata poll pipe.
 637                          */
 638                         lttng_ustconsumer_close_metadata(stream->chan);
 639                         if (rpipe >= 0) {
 640                                 ret = close(rpipe);
 641                                 if (ret < 0) {
 642                                         PERROR("closing metadata pipe read side");
 643                                 }
 644                                 stream->ust_metadata_poll_pipe[0] = -1;
 645                         }
 646                 }
 647                 break;
 648         }
 649         default:
 650                 ERR("Unknown consumer_data type");
 651                 assert(0);
 652         }
 653
 654         /* Close output fd. Could be a socket or local file at this point. */
 655         if (stream->out_fd >= 0) {
 656                 ret = close(stream->out_fd);
 657                 if (ret) {
 658                         PERROR("close");
 659                 }
 660                 stream->out_fd = -1;
 661         }
 662
 663         if (stream->index_file) {
 664                 lttng_index_file_put(stream->index_file);
 665                 stream->index_file = NULL;
 666         }
 667
 668         lttng_trace_chunk_put(stream->trace_chunk);
 669         stream->trace_chunk = NULL;
 670
 671         /* Check and cleanup relayd if needed. */
 672         rcu_read_lock();
 673         relayd = consumer_find_relayd(stream->net_seq_idx);
 674         if (relayd != NULL) {
 675                 consumer_stream_relayd_close(stream, relayd);
 676         }
 677         rcu_read_unlock();
 678 }
 679
 680 /*
 681  * Delete the stream from all possible hash tables.
 682  *
 683  * The consumer data lock MUST be acquired.
 684  * The stream lock MUST be acquired.
 685  */
 686 void consumer_stream_delete(struct lttng_consumer_stream *stream,
 687                 struct lttng_ht *ht)
 688 {
 689         int ret;
 690         struct lttng_ht_iter iter;
 691
 692         assert(stream);
 693         /* Should NEVER be called not in monitor mode. */
 694         assert(stream->chan->monitor);
 695
 696         rcu_read_lock();
 697
 698         if (ht) {
 699                 iter.iter.node = &stream->node.node;
 700                 ret = lttng_ht_del(ht, &iter);
 701                 assert(!ret);
 702         }
 703
 704         /* Delete from stream per channel ID hash table. */
 705         iter.iter.node = &stream->node_channel_id.node;
 706         /*
 707          * The returned value is of no importance. Even if the node is NOT in the
 708          * hash table, we continue since we may have been called by a code path
 709          * that did not add the stream to a (all) hash table. Same goes for the
 710          * next call ht del call.
 711          */
 712         (void) lttng_ht_del(consumer_data.stream_per_chan_id_ht, &iter);
 713
 714         /* Delete from the global stream list. */
 715         iter.iter.node = &stream->node_session_id.node;
 716         /* See the previous ht del on why we ignore the returned value. */
 717         (void) lttng_ht_del(consumer_data.stream_list_ht, &iter);
 718
 719         rcu_read_unlock();
 720
 721         if (!stream->metadata_flag) {
 722                 /* Decrement the stream count of the global consumer data. */
 723                 assert(consumer_data.stream_count > 0);
 724                 consumer_data.stream_count--;
 725         }
 726 }
 727
 728 /*
 729  * Free the given stream within a RCU call.
 730  */
 731 void consumer_stream_free(struct lttng_consumer_stream *stream)
 732 {
 733         assert(stream);
 734
 735         metadata_bucket_destroy(stream->metadata_bucket);
 736         call_rcu(&stream->node.head, free_stream_rcu);
 737 }
 738
 739 /*
 740  * Destroy the stream's buffers of the tracer.
 741  */
 742 void consumer_stream_destroy_buffers(struct lttng_consumer_stream *stream)
 743 {
 744         assert(stream);
 745
 746         switch (consumer_data.type) {
 747         case LTTNG_CONSUMER_KERNEL:
 748                 break;
 749         case LTTNG_CONSUMER32_UST:
 750         case LTTNG_CONSUMER64_UST:
 751                 lttng_ustconsumer_del_stream(stream);
 752                 break;
 753         default:
 754                 ERR("Unknown consumer_data type");
 755                 assert(0);
 756         }
 757 }
 758
 759 /*
 760  * Destroy and close a already created stream.
 761  */
 762 static void destroy_close_stream(struct lttng_consumer_stream *stream)
 763 {
 764         assert(stream);
 765
 766         DBG("Consumer stream destroy monitored key: %" PRIu64, stream->key);
 767
 768         /* Destroy tracer buffers of the stream. */
 769         consumer_stream_destroy_buffers(stream);
 770         /* Close down everything including the relayd if one. */
 771         consumer_stream_close(stream);
 772 }
 773
 774 /*
 775  * Decrement the stream's channel refcount and if down to 0, return the channel
 776  * pointer so it can be destroyed by the caller or NULL if not.
 777  */
 778 static struct lttng_consumer_channel *unref_channel(
 779                 struct lttng_consumer_stream *stream)
 780 {
 781         struct lttng_consumer_channel *free_chan = NULL;
 782
 783         assert(stream);
 784         assert(stream->chan);
 785
 786         /* Update refcount of channel and see if we need to destroy it. */
 787         if (!uatomic_sub_return(&stream->chan->refcount, 1)
 788                         && !uatomic_read(&stream->chan->nb_init_stream_left)) {
 789                 free_chan = stream->chan;
 790         }
 791
 792         return free_chan;
 793 }
 794
 795 /*
 796  * Destroy a stream completely. This will delete, close and free the stream.
 797  * Once return, the stream is NO longer usable. Its channel may get destroyed
 798  * if conditions are met for a monitored stream.
 799  *
 800  * This MUST be called WITHOUT the consumer data and stream lock acquired if
 801  * the stream is in _monitor_ mode else it does not matter.
 802  */
 803 void consumer_stream_destroy(struct lttng_consumer_stream *stream,
 804                 struct lttng_ht *ht)
 805 {
 806         assert(stream);
 807
 808         /* Stream is in monitor mode. */
 809         if (stream->monitor) {
 810                 struct lttng_consumer_channel *free_chan = NULL;
 811
 812                 /*
 813                  * This means that the stream was successfully removed from the streams
 814                  * list of the channel and sent to the right thread managing this
 815                  * stream thus being globally visible.
 816                  */
 817                 if (stream->globally_visible) {
 818                         pthread_mutex_lock(&consumer_data.lock);
 819                         pthread_mutex_lock(&stream->chan->lock);
 820                         pthread_mutex_lock(&stream->lock);
 821                         /* Remove every reference of the stream in the consumer. */
 822                         consumer_stream_delete(stream, ht);
 823
 824                         destroy_close_stream(stream);
 825
 826                         /* Update channel's refcount of the stream. */
 827                         free_chan = unref_channel(stream);
 828
 829                         /* Indicates that the consumer data state MUST be updated after this. */
 830                         consumer_data.need_update = 1;
 831
 832                         pthread_mutex_unlock(&stream->lock);
 833                         pthread_mutex_unlock(&stream->chan->lock);
 834                         pthread_mutex_unlock(&consumer_data.lock);
 835                 } else {
 836                         /*
 837                          * If the stream is not visible globally, this needs to be done
 838                          * outside of the consumer data lock section.
 839                          */
 840                         free_chan = unref_channel(stream);
 841                 }
 842
 843                 if (free_chan) {
 844                         consumer_del_channel(free_chan);
 845                 }
 846         } else {
 847                 destroy_close_stream(stream);
 848         }
 849
 850         /* Free stream within a RCU call. */
 851         lttng_trace_chunk_put(stream->trace_chunk);
 852         stream->trace_chunk = NULL;
 853         consumer_stream_free(stream);
 854 }
 855
 856 /*
 857  * Write index of a specific stream either on the relayd or local disk.
 858  *
 859  * Return 0 on success or else a negative value.
 860  */
 861 int consumer_stream_write_index(struct lttng_consumer_stream *stream,
 862                 struct ctf_packet_index *element)
 863 {
 864         int ret;
 865
 866         assert(stream);
 867         assert(element);
 868
 869         rcu_read_lock();
 870         if (stream->net_seq_idx != (uint64_t) -1ULL) {
 871                 struct consumer_relayd_sock_pair *relayd;
 872                 relayd = consumer_find_relayd(stream->net_seq_idx);
 873                 if (relayd) {
 874                         pthread_mutex_lock(&relayd->ctrl_sock_mutex);
 875                         ret = relayd_send_index(&relayd->control_sock, element,
 876                                 stream->relayd_stream_id, stream->next_net_seq_num - 1);
 877                         if (ret < 0) {
 878                                 /*
 879                                  * Communication error with lttng-relayd,
 880                                  * perform cleanup now
 881                                  */
 882                                 ERR("Relayd send index failed. Cleaning up relayd %" PRIu64 ".", relayd->net_seq_idx);
 883                                 lttng_consumer_cleanup_relayd(relayd);
 884                                 ret = -1;
 885                         }
 886                         pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
 887                 } else {
 888                         ERR("Stream %" PRIu64 " relayd ID %" PRIu64 " unknown. Can't write index.",
 889                                         stream->key, stream->net_seq_idx);
 890                         ret = -1;
 891                 }
 892         } else {
 893                 if (lttng_index_file_write(stream->index_file, element)) {
 894                         ret = -1;
 895                 } else {
 896                         ret = 0;
 897                 }
 898         }
 899         if (ret < 0) {
 900                 goto error;
 901         }
 902
 903 error:
 904         rcu_read_unlock();
 905         return ret;
 906 }
 907
 908 int consumer_stream_create_output_files(struct lttng_consumer_stream *stream,
 909                 bool create_index)
 910 {
 911         int ret;
 912         enum lttng_trace_chunk_status chunk_status;
 913         const int flags = O_WRONLY | O_CREAT | O_TRUNC;
 914         const mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP;
 915         char stream_path[LTTNG_PATH_MAX];
 916
 917         ASSERT_LOCKED(stream->lock);
 918         assert(stream->trace_chunk);
 919
 920         ret = utils_stream_file_path(stream->chan->pathname, stream->name,
 921                         stream->chan->tracefile_size,
 922                         stream->tracefile_count_current, NULL,
 923                         stream_path, sizeof(stream_path));
 924         if (ret < 0) {
 925                 goto end;
 926         }
 927
 928         if (stream->out_fd >= 0) {
 929                 ret = close(stream->out_fd);
 930                 if (ret < 0) {
 931                         PERROR("Failed to close stream file \"%s\"",
 932                                         stream->name);
 933                         goto end;
 934                 }
 935                 stream->out_fd = -1;
 936         }
 937
 938         DBG("Opening stream output file \"%s\"", stream_path);
 939         chunk_status = lttng_trace_chunk_open_file(stream->trace_chunk, stream_path,
 940                         flags, mode, &stream->out_fd, false);
 941         if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) {
 942                 ERR("Failed to open stream file \"%s\"", stream->name);
 943                 ret = -1;
 944                 goto end;
 945         }
 946
 947         if (!stream->metadata_flag && (create_index || stream->index_file)) {
 948                 if (stream->index_file) {
 949                         lttng_index_file_put(stream->index_file);
 950                 }
 951                 chunk_status = lttng_index_file_create_from_trace_chunk(
 952                                 stream->trace_chunk,
 953                                 stream->chan->pathname,
 954                                 stream->name,
 955                                 stream->chan->tracefile_size,
 956                                 stream->tracefile_count_current,
 957                                 CTF_INDEX_MAJOR, CTF_INDEX_MINOR,
 958                                 false, &stream->index_file);
 959                 if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) {
 960                         ret = -1;
 961                         goto end;
 962                 }
 963         }
 964
 965         /* Reset current size because we just perform a rotation. */
 966         stream->tracefile_size_current = 0;
 967         stream->out_fd_offset = 0;
 968 end:
 969         return ret;
 970 }
 971
 972 int consumer_stream_rotate_output_files(struct lttng_consumer_stream *stream)
 973 {
 974         int ret;
 975
 976         stream->tracefile_count_current++;
 977         if (stream->chan->tracefile_count > 0) {
 978                 stream->tracefile_count_current %=
 979                                 stream->chan->tracefile_count;
 980         }
 981
 982         DBG("Rotating output files of stream \"%s\"", stream->name);
 983         ret = consumer_stream_create_output_files(stream, true);
 984         if (ret) {
 985                 goto end;
 986         }
 987
 988 end:
 989         return ret;
 990 }
 991
 992 bool consumer_stream_is_deleted(struct lttng_consumer_stream *stream)
 993 {
 994         /*
 995          * This function does not take a const stream since
 996          * cds_lfht_is_node_deleted was not const before liburcu 0.12.
 997          */
 998         assert(stream);
 999         return cds_lfht_is_node_deleted(&stream->node.node);
1000 }
1001
1002 static ssize_t metadata_bucket_flush(
1003                 const struct stream_subbuffer *buffer, void *data)
1004 {
1005         ssize_t ret;
1006         struct lttng_consumer_stream *stream = data;
1007
1008         ret = consumer_stream_consume_mmap(NULL, stream, buffer);
1009         if (ret < 0) {
1010                 goto end;
1011         }
1012 end:
1013         return ret;
1014 }
1015
1016 static ssize_t metadata_bucket_consume(
1017                 struct lttng_consumer_local_data *unused,
1018                 struct lttng_consumer_stream *stream,
1019                 const struct stream_subbuffer *subbuffer)
1020 {
1021         ssize_t ret;
1022         enum metadata_bucket_status status;
1023
1024         status = metadata_bucket_fill(stream->metadata_bucket, subbuffer);
1025         switch (status) {
1026         case METADATA_BUCKET_STATUS_OK:
1027                 /* Return consumed size. */
1028                 ret = subbuffer->buffer.buffer.size;
1029                 break;
1030         default:
1031                 ret = -1;
1032         }
1033
1034         return ret;
1035 }
1036
1037 int consumer_stream_enable_metadata_bucketization(
1038                 struct lttng_consumer_stream *stream)
1039 {
1040         int ret = 0;
1041
1042         assert(stream->metadata_flag);
1043         assert(!stream->metadata_bucket);
1044         assert(stream->chan->output == CONSUMER_CHANNEL_MMAP);
1045
1046         stream->metadata_bucket = metadata_bucket_create(
1047                         metadata_bucket_flush, stream);
1048         if (!stream->metadata_bucket) {
1049                 ret = -1;
1050                 goto end;
1051         }
1052
1053         stream->read_subbuffer_ops.consume_subbuffer = metadata_bucket_consume;
1054 end:
1055         return ret;
1056 }
1057
1058 void consumer_stream_metadata_set_version(
1059                 struct lttng_consumer_stream *stream, uint64_t new_version)
1060 {
1061         assert(new_version > stream->metadata_version);
1062         stream->metadata_version = new_version;
1063         stream->reset_metadata_flag = 1;
1064
1065         if (stream->metadata_bucket) {
1066                 metadata_bucket_reset(stream->metadata_bucket);
1067         }
1068 }