src/common/consumer/consumer-stream.c

   1 /*
   2  * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
   3  *                      Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   4  * Copyright (C) 2013 - David Goulet <dgoulet@efficios.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License, version 2 only, as
   8  * published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
  13  * more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along with
  16  * this program; if not, write to the Free Software Foundation, Inc., 51
  17  * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18  */
  19
  20 #define _LGPL_SOURCE
  21 #include <assert.h>
  22 #include <inttypes.h>
  23 #include <sys/mman.h>
  24 #include <unistd.h>
  25
  26 #include <common/common.h>
  27 #include <common/index/index.h>
  28 #include <common/kernel-consumer/kernel-consumer.h>
  29 #include <common/relayd/relayd.h>
  30 #include <common/ust-consumer/ust-consumer.h>
  31 #include <common/utils.h>
  32 #include <common/consumer/consumer.h>
  33 #include <common/consumer/consumer-timer.h>
  34 #include <common/consumer/metadata-bucket.h>
  35
  36 #include "consumer-stream.h"
  37
  38 /*
  39  * RCU call to free stream. MUST only be used with call_rcu().
  40  */
  41 static void free_stream_rcu(struct rcu_head *head)
  42 {
  43         struct lttng_ht_node_u64 *node =
  44                 caa_container_of(head, struct lttng_ht_node_u64, head);
  45         struct lttng_consumer_stream *stream =
  46                 caa_container_of(node, struct lttng_consumer_stream, node);
  47
  48         pthread_mutex_destroy(&stream->lock);
  49         free(stream);
  50 }
  51
  52 static void consumer_stream_data_lock_all(struct lttng_consumer_stream *stream)
  53 {
  54         pthread_mutex_lock(&stream->chan->lock);
  55         pthread_mutex_lock(&stream->lock);
  56 }
  57
  58 static void consumer_stream_data_unlock_all(struct lttng_consumer_stream *stream)
  59 {
  60         pthread_mutex_unlock(&stream->lock);
  61         pthread_mutex_unlock(&stream->chan->lock);
  62 }
  63
  64 static void consumer_stream_metadata_lock_all(struct lttng_consumer_stream *stream)
  65 {
  66         consumer_stream_data_lock_all(stream);
  67         pthread_mutex_lock(&stream->metadata_rdv_lock);
  68 }
  69
  70 static void consumer_stream_metadata_unlock_all(struct lttng_consumer_stream *stream)
  71 {
  72         pthread_mutex_unlock(&stream->metadata_rdv_lock);
  73         consumer_stream_data_unlock_all(stream);
  74 }
  75
  76 /* Only used for data streams. */
  77 static int consumer_stream_update_stats(struct lttng_consumer_stream *stream,
  78                 const struct stream_subbuffer *subbuf)
  79 {
  80         int ret = 0;
  81         uint64_t sequence_number;
  82         const uint64_t discarded_events =
  83                         LTTNG_OPTIONAL_GET(subbuf->info.data.sequence_number);
  84
  85         if (!subbuf->info.data.sequence_number.is_set) {
  86                 /* Command not supported by the tracer. */
  87                 sequence_number = -1ULL;
  88         } else {
  89                 sequence_number = subbuf->info.data.sequence_number.value;
  90         }
  91
  92         /*
  93          * Start the sequence when we extract the first packet in case we don't
  94          * start at 0 (for example if a consumer is not connected to the
  95          * session immediately after the beginning).
  96          */
  97         if (stream->last_sequence_number == -1ULL) {
  98                 stream->last_sequence_number = sequence_number;
  99         } else if (sequence_number > stream->last_sequence_number) {
 100                 stream->chan->lost_packets += sequence_number -
 101                                 stream->last_sequence_number - 1;
 102         } else {
 103                 /* seq <= last_sequence_number */
 104                 ERR("Sequence number inconsistent : prev = %" PRIu64
 105                     ", current = %" PRIu64,
 106                                 stream->last_sequence_number, sequence_number);
 107                 ret = -1;
 108                 goto end;
 109         }
 110         stream->last_sequence_number = sequence_number;
 111
 112         if (discarded_events < stream->last_discarded_events) {
 113                 /*
 114                  * Overflow has occurred. We assume only one wrap-around
 115                  * has occurred.
 116                  */
 117                 stream->chan->discarded_events +=
 118                                 (1ULL << (CAA_BITS_PER_LONG - 1)) -
 119                                 stream->last_discarded_events +
 120                                 discarded_events;
 121         } else {
 122                 stream->chan->discarded_events += discarded_events -
 123                                                   stream->last_discarded_events;
 124         }
 125         stream->last_discarded_events = discarded_events;
 126         ret = 0;
 127
 128 end:
 129         return ret;
 130 }
 131
 132 static
 133 void ctf_packet_index_populate(struct ctf_packet_index *index,
 134                 off_t offset, const struct stream_subbuffer *subbuffer)
 135 {
 136         *index = (typeof(*index)){
 137                 .offset = htobe64(offset),
 138                 .packet_size = htobe64(subbuffer->info.data.packet_size),
 139                 .content_size = htobe64(subbuffer->info.data.content_size),
 140                 .timestamp_begin = htobe64(
 141                                 subbuffer->info.data.timestamp_begin),
 142                 .timestamp_end = htobe64(
 143                                 subbuffer->info.data.timestamp_end),
 144                 .events_discarded = htobe64(
 145                                 subbuffer->info.data.events_discarded),
 146                 .stream_id = htobe64(subbuffer->info.data.stream_id),
 147                 .stream_instance_id = htobe64(
 148                                 subbuffer->info.data.stream_instance_id.is_set ?
 149                                 subbuffer->info.data.stream_instance_id.value : -1ULL),
 150                 .packet_seq_num = htobe64(
 151                                 subbuffer->info.data.sequence_number.is_set ?
 152                                 subbuffer->info.data.sequence_number.value : -1ULL),
 153         };
 154 }
 155
 156 static ssize_t consumer_stream_consume_mmap(
 157                 struct lttng_consumer_local_data *ctx,
 158                 struct lttng_consumer_stream *stream,
 159                 const struct stream_subbuffer *subbuffer)
 160 {
 161         const unsigned long padding_size =
 162                         subbuffer->info.data.padded_subbuf_size -
 163                         subbuffer->info.data.subbuf_size;
 164
 165         return lttng_consumer_on_read_subbuffer_mmap(
 166                         stream, &subbuffer->buffer.buffer, padding_size);
 167 }
 168
 169 static ssize_t consumer_stream_consume_splice(
 170                 struct lttng_consumer_local_data *ctx,
 171                 struct lttng_consumer_stream *stream,
 172                 const struct stream_subbuffer *subbuffer)
 173 {
 174         return lttng_consumer_on_read_subbuffer_splice(ctx, stream,
 175                         subbuffer->info.data.padded_subbuf_size, 0);
 176 }
 177
 178 static int consumer_stream_send_index(
 179                 struct lttng_consumer_stream *stream,
 180                 const struct stream_subbuffer *subbuffer,
 181                 struct lttng_consumer_local_data *ctx)
 182 {
 183         off_t packet_offset = 0;
 184         struct ctf_packet_index index = {};
 185
 186         /*
 187          * This is called after consuming the sub-buffer; substract the
 188          * effect this sub-buffer from the offset.
 189          */
 190         if (stream->relayd_id == (uint64_t) -1ULL) {
 191                 packet_offset = stream->out_fd_offset -
 192                                 subbuffer->info.data.padded_subbuf_size;
 193         }
 194
 195         ctf_packet_index_populate(&index, packet_offset, subbuffer);
 196         return consumer_stream_write_index(stream, &index);
 197 }
 198
 199 /*
 200  * Actually do the metadata sync using the given metadata stream.
 201  *
 202  * Return 0 on success else a negative value. ENODATA can be returned also
 203  * indicating that there is no metadata available for that stream.
 204  */
 205 static int do_sync_metadata(struct lttng_consumer_stream *metadata,
 206                 struct lttng_consumer_local_data *ctx)
 207 {
 208         int ret;
 209
 210         assert(metadata);
 211         assert(metadata->metadata_flag);
 212         assert(ctx);
 213
 214         /*
 215          * In UST, since we have to write the metadata from the cache packet
 216          * by packet, we might need to start this procedure multiple times
 217          * until all the metadata from the cache has been extracted.
 218          */
 219         do {
 220                 /*
 221                  * Steps :
 222                  * - Lock the metadata stream
 223                  * - Check if metadata stream node was deleted before locking.
 224                  *   - if yes, release and return success
 225                  * - Check if new metadata is ready (flush + snapshot pos)
 226                  * - If nothing : release and return.
 227                  * - Lock the metadata_rdv_lock
 228                  * - Unlock the metadata stream
 229                  * - cond_wait on metadata_rdv to wait the wakeup from the
 230                  *   metadata thread
 231                  * - Unlock the metadata_rdv_lock
 232                  */
 233                 pthread_mutex_lock(&metadata->lock);
 234
 235                 /*
 236                  * There is a possibility that we were able to acquire a reference on the
 237                  * stream from the RCU hash table but between then and now, the node might
 238                  * have been deleted just before the lock is acquired. Thus, after locking,
 239                  * we make sure the metadata node has not been deleted which means that the
 240                  * buffers are closed.
 241                  *
 242                  * In that case, there is no need to sync the metadata hence returning a
 243                  * success return code.
 244                  */
 245                 ret = cds_lfht_is_node_deleted(&metadata->node.node);
 246                 if (ret) {
 247                         ret = 0;
 248                         goto end_unlock_mutex;
 249                 }
 250
 251                 switch (ctx->type) {
 252                 case LTTNG_CONSUMER_KERNEL:
 253                         /*
 254                          * Empty the metadata cache and flush the current stream.
 255                          */
 256                         ret = lttng_kconsumer_sync_metadata(metadata);
 257                         break;
 258                 case LTTNG_CONSUMER32_UST:
 259                 case LTTNG_CONSUMER64_UST:
 260                         /*
 261                          * Ask the sessiond if we have new metadata waiting and update the
 262                          * consumer metadata cache.
 263                          */
 264                         ret = lttng_ustconsumer_sync_metadata(ctx, metadata);
 265                         break;
 266                 default:
 267                         assert(0);
 268                         ret = -1;
 269                         break;
 270                 }
 271                 /*
 272                  * Error or no new metadata, we exit here.
 273                  */
 274                 if (ret <= 0 || ret == ENODATA) {
 275                         goto end_unlock_mutex;
 276                 }
 277
 278                 /*
 279                  * At this point, new metadata have been flushed, so we wait on the
 280                  * rendez-vous point for the metadata thread to wake us up when it
 281                  * finishes consuming the metadata and continue execution.
 282                  */
 283
 284                 pthread_mutex_lock(&metadata->metadata_rdv_lock);
 285
 286                 /*
 287                  * Release metadata stream lock so the metadata thread can process it.
 288                  */
 289                 pthread_mutex_unlock(&metadata->lock);
 290
 291                 /*
 292                  * Wait on the rendez-vous point. Once woken up, it means the metadata was
 293                  * consumed and thus synchronization is achieved.
 294                  */
 295                 pthread_cond_wait(&metadata->metadata_rdv, &metadata->metadata_rdv_lock);
 296                 pthread_mutex_unlock(&metadata->metadata_rdv_lock);
 297         } while (ret == EAGAIN);
 298
 299         /* Success */
 300         return 0;
 301
 302 end_unlock_mutex:
 303         pthread_mutex_unlock(&metadata->lock);
 304         return ret;
 305 }
 306
 307 /*
 308  * Synchronize the metadata using a given session ID. A successful acquisition
 309  * of a metadata stream will trigger a request to the session daemon and a
 310  * snapshot so the metadata thread can consume it.
 311  *
 312  * This function call is a rendez-vous point between the metadata thread and
 313  * the data thread.
 314  *
 315  * Return 0 on success or else a negative value.
 316  */
 317 int consumer_stream_sync_metadata(struct lttng_consumer_local_data *ctx,
 318                 uint64_t session_id)
 319 {
 320         int ret;
 321         struct lttng_consumer_stream *stream = NULL;
 322         struct lttng_ht_iter iter;
 323         struct lttng_ht *ht;
 324
 325         assert(ctx);
 326
 327         /* Ease our life a bit. */
 328         ht = consumer_data.stream_list_ht;
 329
 330         rcu_read_lock();
 331
 332         /* Search the metadata associated with the session id of the given stream. */
 333
 334         cds_lfht_for_each_entry_duplicate(ht->ht,
 335                         ht->hash_fct(&session_id, lttng_ht_seed), ht->match_fct,
 336                         &session_id, &iter.iter, stream, node_session_id.node) {
 337                 if (!stream->metadata_flag) {
 338                         continue;
 339                 }
 340
 341                 ret = do_sync_metadata(stream, ctx);
 342                 if (ret < 0) {
 343                         goto end;
 344                 }
 345         }
 346
 347         /*
 348          * Force return code to 0 (success) since ret might be ENODATA for instance
 349          * which is not an error but rather that we should come back.
 350          */
 351         ret = 0;
 352
 353 end:
 354         rcu_read_unlock();
 355         return ret;
 356 }
 357
 358 static int consumer_stream_sync_metadata_index(
 359                 struct lttng_consumer_stream *stream,
 360                 const struct stream_subbuffer *subbuffer,
 361                 struct lttng_consumer_local_data *ctx)
 362 {
 363         int ret;
 364
 365         /* Block until all the metadata is sent. */
 366         pthread_mutex_lock(&stream->metadata_timer_lock);
 367         assert(!stream->missed_metadata_flush);
 368         stream->waiting_on_metadata = true;
 369         pthread_mutex_unlock(&stream->metadata_timer_lock);
 370
 371         ret = consumer_stream_sync_metadata(ctx, stream->session_id);
 372
 373         pthread_mutex_lock(&stream->metadata_timer_lock);
 374         stream->waiting_on_metadata = false;
 375         if (stream->missed_metadata_flush) {
 376                 stream->missed_metadata_flush = false;
 377                 pthread_mutex_unlock(&stream->metadata_timer_lock);
 378                 (void) stream->read_subbuffer_ops.send_live_beacon(stream);
 379         } else {
 380                 pthread_mutex_unlock(&stream->metadata_timer_lock);
 381         }
 382         if (ret < 0) {
 383                 goto end;
 384         }
 385
 386         ret = consumer_stream_send_index(stream, subbuffer, ctx);
 387 end:
 388         return ret;
 389 }
 390
 391 /*
 392  * Check if the local version of the metadata stream matches with the version
 393  * of the metadata stream in the kernel. If it was updated, set the reset flag
 394  * on the stream.
 395  */
 396 static
 397 int metadata_stream_check_version(struct lttng_consumer_stream *stream,
 398         const struct stream_subbuffer *subbuffer)
 399 {
 400         if (stream->metadata_version == subbuffer->info.metadata.version) {
 401                 goto end;
 402         }
 403
 404         DBG("New metadata version detected");
 405         consumer_stream_metadata_set_version(stream,
 406                         subbuffer->info.metadata.version);
 407
 408         if (stream->read_subbuffer_ops.reset_metadata) {
 409                 stream->read_subbuffer_ops.reset_metadata(stream);
 410         }
 411
 412 end:
 413         return 0;
 414 }
 415
 416 struct lttng_consumer_stream *consumer_stream_create(
 417                 struct lttng_consumer_channel *channel,
 418                 uint64_t channel_key,
 419                 uint64_t stream_key,
 420                 enum lttng_consumer_stream_state state,
 421                 const char *channel_name,
 422                 uid_t uid,
 423                 gid_t gid,
 424                 uint64_t relayd_id,
 425                 uint64_t session_id,
 426                 int cpu,
 427                 int *alloc_ret,
 428                 enum consumer_channel_type type,
 429                 unsigned int monitor)
 430 {
 431         int ret;
 432         struct lttng_consumer_stream *stream;
 433
 434         stream = zmalloc(sizeof(*stream));
 435         if (stream == NULL) {
 436                 PERROR("malloc struct lttng_consumer_stream");
 437                 ret = -ENOMEM;
 438                 goto end;
 439         }
 440
 441         rcu_read_lock();
 442         stream->chan = channel;
 443         stream->key = stream_key;
 444         stream->out_fd = -1;
 445         stream->out_fd_offset = 0;
 446         stream->output_written = 0;
 447         stream->state = state;
 448         stream->uid = uid;
 449         stream->gid = gid;
 450         stream->relayd_id = relayd_id;
 451         stream->session_id = session_id;
 452         stream->monitor = monitor;
 453         stream->endpoint_status = CONSUMER_ENDPOINT_ACTIVE;
 454         stream->index_file = NULL;
 455         stream->last_sequence_number = -1ULL;
 456         pthread_mutex_init(&stream->lock, NULL);
 457         pthread_mutex_init(&stream->metadata_timer_lock, NULL);
 458
 459         /* If channel is the metadata, flag this stream as metadata. */
 460         if (type == CONSUMER_CHANNEL_TYPE_METADATA) {
 461                 stream->metadata_flag = 1;
 462                 /* Metadata is flat out. */
 463                 strncpy(stream->name, DEFAULT_METADATA_NAME, sizeof(stream->name));
 464                 /* Live rendez-vous point. */
 465                 pthread_cond_init(&stream->metadata_rdv, NULL);
 466                 pthread_mutex_init(&stream->metadata_rdv_lock, NULL);
 467         } else {
 468                 /* Format stream name to <channel_name>_<cpu_number> */
 469                 ret = snprintf(stream->name, sizeof(stream->name), "%s_%d",
 470                                 channel_name, cpu);
 471                 if (ret < 0) {
 472                         PERROR("snprintf stream name");
 473                         goto error;
 474                 }
 475         }
 476
 477         /* Key is always the wait_fd for streams. */
 478         lttng_ht_node_init_u64(&stream->node, stream->key);
 479
 480         /* Init node per channel id key */
 481         lttng_ht_node_init_u64(&stream->node_channel_id, channel_key);
 482
 483         /* Init session id node with the stream session id */
 484         lttng_ht_node_init_u64(&stream->node_session_id, stream->session_id);
 485
 486         DBG3("Allocated stream %s (key %" PRIu64 ", chan_key %" PRIu64
 487                         " relayd_id %" PRIu64 ", session_id %" PRIu64,
 488                         stream->name, stream->key, channel_key,
 489                         stream->relayd_id, stream->session_id);
 490
 491         rcu_read_unlock();
 492
 493         switch (channel->output) {
 494         case CONSUMER_CHANNEL_SPLICE:
 495                 stream->output = LTTNG_EVENT_SPLICE;
 496                 ret = utils_create_pipe(stream->splice_pipe);
 497                 if (ret < 0) {
 498                         goto error;
 499                 }
 500                 break;
 501         case CONSUMER_CHANNEL_MMAP:
 502                 stream->output = LTTNG_EVENT_MMAP;
 503                 break;
 504         default:
 505                 abort();
 506         }
 507
 508         if (type == CONSUMER_CHANNEL_TYPE_METADATA) {
 509                 stream->read_subbuffer_ops.lock =
 510                                 consumer_stream_metadata_lock_all;
 511                 stream->read_subbuffer_ops.unlock =
 512                                 consumer_stream_metadata_unlock_all;
 513                 stream->read_subbuffer_ops.pre_consume_subbuffer =
 514                                 metadata_stream_check_version;
 515         } else {
 516                 stream->read_subbuffer_ops.lock = consumer_stream_data_lock_all;
 517                 stream->read_subbuffer_ops.unlock =
 518                                 consumer_stream_data_unlock_all;
 519                 stream->read_subbuffer_ops.pre_consume_subbuffer =
 520                                 consumer_stream_update_stats;
 521                 if (channel->is_live) {
 522                         stream->read_subbuffer_ops.post_consume =
 523                                         consumer_stream_sync_metadata_index;
 524                 } else {
 525                         stream->read_subbuffer_ops.post_consume =
 526                                         consumer_stream_send_index;
 527                 }
 528         }
 529
 530         if (channel->output == CONSUMER_CHANNEL_MMAP) {
 531                 stream->read_subbuffer_ops.consume_subbuffer =
 532                                 consumer_stream_consume_mmap;
 533         } else {
 534                 stream->read_subbuffer_ops.consume_subbuffer =
 535                                 consumer_stream_consume_splice;
 536         }
 537
 538         return stream;
 539
 540 error:
 541         rcu_read_unlock();
 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         if (ret < 0) {
 576                 ERR("Relayd send close stream failed. Cleaning up relayd %" PRIu64 ".", relayd->id);
 577                 lttng_consumer_cleanup_relayd(relayd);
 578         }
 579         pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
 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->relayd_id = (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         /* Check and cleanup relayd if needed. */
 669         rcu_read_lock();
 670         relayd = consumer_find_relayd(stream->relayd_id);
 671         if (relayd != NULL) {
 672                 consumer_stream_relayd_close(stream, relayd);
 673         }
 674         rcu_read_unlock();
 675 }
 676
 677 /*
 678  * Delete the stream from all possible hash tables.
 679  *
 680  * The consumer data lock MUST be acquired.
 681  * The stream lock MUST be acquired.
 682  */
 683 void consumer_stream_delete(struct lttng_consumer_stream *stream,
 684                 struct lttng_ht *ht)
 685 {
 686         int ret;
 687         struct lttng_ht_iter iter;
 688
 689         assert(stream);
 690         /* Should NEVER be called not in monitor mode. */
 691         assert(stream->chan->monitor);
 692
 693         rcu_read_lock();
 694
 695         if (ht) {
 696                 iter.iter.node = &stream->node.node;
 697                 ret = lttng_ht_del(ht, &iter);
 698                 assert(!ret);
 699         }
 700
 701         /* Delete from stream per channel ID hash table. */
 702         iter.iter.node = &stream->node_channel_id.node;
 703         /*
 704          * The returned value is of no importance. Even if the node is NOT in the
 705          * hash table, we continue since we may have been called by a code path
 706          * that did not add the stream to a (all) hash table. Same goes for the
 707          * next call ht del call.
 708          */
 709         (void) lttng_ht_del(consumer_data.stream_per_chan_id_ht, &iter);
 710
 711         /* Delete from the global stream list. */
 712         iter.iter.node = &stream->node_session_id.node;
 713         /* See the previous ht del on why we ignore the returned value. */
 714         (void) lttng_ht_del(consumer_data.stream_list_ht, &iter);
 715
 716         rcu_read_unlock();
 717
 718         if (!stream->metadata_flag) {
 719                 /* Decrement the stream count of the global consumer data. */
 720                 assert(consumer_data.stream_count > 0);
 721                 consumer_data.stream_count--;
 722         }
 723 }
 724
 725 /*
 726  * Free the given stream within a RCU call.
 727  */
 728 void consumer_stream_free(struct lttng_consumer_stream *stream)
 729 {
 730         assert(stream);
 731
 732         metadata_bucket_destroy(stream->metadata_bucket);
 733         call_rcu(&stream->node.head, free_stream_rcu);
 734 }
 735
 736 /*
 737  * Destroy the stream's buffers of the tracer.
 738  */
 739 void consumer_stream_destroy_buffers(struct lttng_consumer_stream *stream)
 740 {
 741         assert(stream);
 742
 743         switch (consumer_data.type) {
 744         case LTTNG_CONSUMER_KERNEL:
 745                 break;
 746         case LTTNG_CONSUMER32_UST:
 747         case LTTNG_CONSUMER64_UST:
 748                 lttng_ustconsumer_del_stream(stream);
 749                 break;
 750         default:
 751                 ERR("Unknown consumer_data type");
 752                 assert(0);
 753         }
 754 }
 755
 756 /*
 757  * Destroy and close a already created stream.
 758  */
 759 static void destroy_close_stream(struct lttng_consumer_stream *stream)
 760 {
 761         assert(stream);
 762
 763         DBG("Consumer stream destroy monitored key: %" PRIu64, stream->key);
 764
 765         /* Destroy tracer buffers of the stream. */
 766         consumer_stream_destroy_buffers(stream);
 767         /* Close down everything including the relayd if one. */
 768         consumer_stream_close(stream);
 769 }
 770
 771 /*
 772  * Decrement the stream's channel refcount and if down to 0, return the channel
 773  * pointer so it can be destroyed by the caller or NULL if not.
 774  */
 775 static struct lttng_consumer_channel *unref_channel(
 776                 struct lttng_consumer_stream *stream)
 777 {
 778         struct lttng_consumer_channel *free_chan = NULL;
 779
 780         assert(stream);
 781         assert(stream->chan);
 782
 783         /* Update refcount of channel and see if we need to destroy it. */
 784         if (!uatomic_sub_return(&stream->chan->refcount, 1)
 785                         && !uatomic_read(&stream->chan->nb_init_stream_left)) {
 786                 free_chan = stream->chan;
 787         }
 788
 789         return free_chan;
 790 }
 791
 792 /*
 793  * Destroy a stream completely. This will delete, close and free the stream.
 794  * Once return, the stream is NO longer usable. Its channel may get destroyed
 795  * if conditions are met for a monitored stream.
 796  *
 797  * This MUST be called WITHOUT the consumer data and stream lock acquired if
 798  * the stream is in _monitor_ mode else it does not matter.
 799  */
 800 void consumer_stream_destroy(struct lttng_consumer_stream *stream,
 801                 struct lttng_ht *ht)
 802 {
 803         assert(stream);
 804
 805         /* Stream is in monitor mode. */
 806         if (stream->monitor) {
 807                 struct lttng_consumer_channel *free_chan = NULL;
 808
 809                 /*
 810                  * This means that the stream was successfully removed from the streams
 811                  * list of the channel and sent to the right thread managing this
 812                  * stream thus being globally visible.
 813                  */
 814                 if (stream->globally_visible) {
 815                         pthread_mutex_lock(&consumer_data.lock);
 816                         pthread_mutex_lock(&stream->chan->lock);
 817                         pthread_mutex_lock(&stream->lock);
 818                         /* Remove every reference of the stream in the consumer. */
 819                         consumer_stream_delete(stream, ht);
 820
 821                         destroy_close_stream(stream);
 822
 823                         /* Update channel's refcount of the stream. */
 824                         free_chan = unref_channel(stream);
 825
 826                         /* Indicates that the consumer data state MUST be updated after this. */
 827                         consumer_data.need_update = 1;
 828
 829                         pthread_mutex_unlock(&stream->lock);
 830                         pthread_mutex_unlock(&stream->chan->lock);
 831                         pthread_mutex_unlock(&consumer_data.lock);
 832                 } else {
 833                         /*
 834                          * If the stream is not visible globally, this needs to be done
 835                          * outside of the consumer data lock section.
 836                          */
 837                         free_chan = unref_channel(stream);
 838                 }
 839
 840                 if (free_chan) {
 841                         consumer_del_channel(free_chan);
 842                 }
 843         } else {
 844                 destroy_close_stream(stream);
 845         }
 846
 847         /* Free stream within a RCU call. */
 848         consumer_stream_free(stream);
 849 }
 850
 851 /*
 852  * Write index of a specific stream either on the relayd or local disk.
 853  *
 854  * Return 0 on success or else a negative value.
 855  */
 856 int consumer_stream_write_index(struct lttng_consumer_stream *stream,
 857                 struct ctf_packet_index *element)
 858 {
 859         int ret;
 860
 861         assert(stream);
 862         assert(element);
 863
 864         rcu_read_lock();
 865         if (stream->relayd_id != (uint64_t) -1ULL) {
 866                 struct consumer_relayd_sock_pair *relayd;
 867
 868                 relayd = consumer_find_relayd(stream->relayd_id);
 869                 if (relayd) {
 870                         pthread_mutex_lock(&relayd->ctrl_sock_mutex);
 871                         ret = relayd_send_index(&relayd->control_sock, element,
 872                                 stream->relayd_stream_id, stream->next_net_seq_num - 1);
 873                         if (ret < 0) {
 874                                 /*
 875                                  * Communication error with lttng-relayd,
 876                                  * perform cleanup now
 877                                  */
 878                                 ERR("Relayd send index failed. Cleaning up relayd %" PRIu64 ".", relayd->id);
 879                                 lttng_consumer_cleanup_relayd(relayd);
 880                                 ret = -1;
 881                         }
 882                         pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
 883                 } else {
 884                         ERR("Stream %" PRIu64 " relayd ID %" PRIu64 " unknown. Can't write index.",
 885                                         stream->key, stream->relayd_id);
 886                         ret = -1;
 887                 }
 888         } else {
 889                 if (lttng_index_file_write(stream->index_file, element)) {
 890                         ret = -1;
 891                 } else {
 892                         ret = 0;
 893                 }
 894         }
 895         if (ret < 0) {
 896                 goto error;
 897         }
 898
 899 error:
 900         rcu_read_unlock();
 901         return ret;
 902 }
 903
 904 static ssize_t metadata_bucket_flush(
 905                 const struct stream_subbuffer *buffer, void *data)
 906 {
 907         ssize_t ret;
 908         struct lttng_consumer_stream *stream = data;
 909
 910         ret = consumer_stream_consume_mmap(NULL, stream, buffer);
 911         if (ret < 0) {
 912                 goto end;
 913         }
 914 end:
 915         return ret;
 916 }
 917
 918 static ssize_t metadata_bucket_consume(
 919                 struct lttng_consumer_local_data *unused,
 920                 struct lttng_consumer_stream *stream,
 921                 const struct stream_subbuffer *subbuffer)
 922 {
 923         ssize_t ret;
 924         enum metadata_bucket_status status;
 925
 926         status = metadata_bucket_fill(stream->metadata_bucket, subbuffer);
 927         switch (status) {
 928         case METADATA_BUCKET_STATUS_OK:
 929                 /* Return consumed size. */
 930                 ret = subbuffer->buffer.buffer.size;
 931                 break;
 932         default:
 933                 ret = -1;
 934         }
 935
 936         return ret;
 937 }
 938
 939 int consumer_stream_enable_metadata_bucketization(
 940                 struct lttng_consumer_stream *stream)
 941 {
 942         int ret = 0;
 943
 944         assert(stream->metadata_flag);
 945         assert(!stream->metadata_bucket);
 946         assert(stream->chan->output == CONSUMER_CHANNEL_MMAP);
 947
 948         stream->metadata_bucket = metadata_bucket_create(
 949                         metadata_bucket_flush, stream);
 950         if (!stream->metadata_bucket) {
 951                 ret = -1;
 952                 goto end;
 953         }
 954
 955         stream->read_subbuffer_ops.consume_subbuffer = metadata_bucket_consume;
 956 end:
 957         return ret;
 958 }
 959
 960 void consumer_stream_metadata_set_version(
 961                 struct lttng_consumer_stream *stream, uint64_t new_version)
 962 {
 963         assert(new_version > stream->metadata_version);
 964         stream->metadata_version = new_version;
 965         stream->reset_metadata_flag = 1;
 966
 967         if (stream->metadata_bucket) {
 968                 metadata_bucket_reset(stream->metadata_bucket);
 969         }
 970 }