src/bin/lttng-sessiond/kernel-consumer.c

   1 /*
   2  * Copyright (C) 2012 - David Goulet <dgoulet@efficios.com>
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License, version 2 only, as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, write to the Free Software Foundation, Inc., 51
  15  * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  16  */
  17
  18 #define _LGPL_SOURCE
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <sys/stat.h>
  22 #include <unistd.h>
  23 #include <inttypes.h>
  24
  25 #include <common/common.h>
  26 #include <common/defaults.h>
  27 #include <common/compat/string.h>
  28
  29 #include "consumer.h"
  30 #include "health-sessiond.h"
  31 #include "kernel-consumer.h"
  32 #include "notification-thread-commands.h"
  33 #include "session.h"
  34 #include "lttng-sessiond.h"
  35
  36 static char *create_channel_path(struct consumer_output *consumer,
  37                 uid_t uid, gid_t gid)
  38 {
  39         int ret;
  40         char tmp_path[PATH_MAX];
  41         char *pathname = NULL;
  42
  43         assert(consumer);
  44
  45         /* Get the right path name destination */
  46         if (consumer->type == CONSUMER_DST_LOCAL) {
  47                 /* Set application path to the destination path */
  48                 ret = snprintf(tmp_path, sizeof(tmp_path), "%s%s%s",
  49                                 consumer->dst.session_root_path,
  50                                 consumer->chunk_path,
  51                                 consumer->subdir);
  52                 if (ret < 0) {
  53                         PERROR("snprintf kernel channel path");
  54                         goto error;
  55                 } else if (ret >= sizeof(tmp_path)) {
  56                         ERR("Kernel channel path exceeds the maximal allowed length of of %zu bytes (%i bytes required) with path \"%s%s%s\"",
  57                                         sizeof(tmp_path), ret,
  58                                         consumer->dst.session_root_path,
  59                                         consumer->chunk_path,
  60                                         consumer->subdir);
  61                         goto error;
  62                 }
  63                 pathname = lttng_strndup(tmp_path, sizeof(tmp_path));
  64                 if (!pathname) {
  65                         PERROR("lttng_strndup");
  66                         goto error;
  67                 }
  68
  69                 /* Create directory */
  70                 ret = run_as_mkdir_recursive(pathname, S_IRWXU | S_IRWXG, uid, gid);
  71                 if (ret < 0) {
  72                         if (errno != EEXIST) {
  73                                 ERR("Trace directory creation error");
  74                                 goto error;
  75                         }
  76                 }
  77                 DBG3("Kernel local consumer tracefile path: %s", pathname);
  78         } else {
  79                 ret = snprintf(tmp_path, sizeof(tmp_path), "%s%s",
  80                                 consumer->dst.net.base_dir,
  81                                 consumer->subdir);
  82                 if (ret < 0) {
  83                         PERROR("snprintf kernel metadata path");
  84                         goto error;
  85                 } else if (ret >= sizeof(tmp_path)) {
  86                         ERR("Kernel channel path exceeds the maximal allowed length of of %zu bytes (%i bytes required) with path \"%s%s\"",
  87                                         sizeof(tmp_path), ret,
  88                                         consumer->dst.net.base_dir,
  89                                         consumer->subdir);
  90                         goto error;
  91                 }
  92                 pathname = lttng_strndup(tmp_path, sizeof(tmp_path));
  93                 if (!pathname) {
  94                         PERROR("lttng_strndup");
  95                         goto error;
  96                 }
  97                 DBG3("Kernel network consumer subdir path: %s", pathname);
  98         }
  99
 100         return pathname;
 101
 102 error:
 103         free(pathname);
 104         return NULL;
 105 }
 106
 107 /*
 108  * Sending a single channel to the consumer with command ADD_CHANNEL.
 109  */
 110 int kernel_consumer_add_channel(struct consumer_socket *sock,
 111                 struct ltt_kernel_channel *channel,
 112                 struct ltt_kernel_session *ksession,
 113                 unsigned int monitor)
 114 {
 115         int ret;
 116         char *pathname;
 117         struct lttcomm_consumer_msg lkm;
 118         struct consumer_output *consumer;
 119         enum lttng_error_code status;
 120         struct ltt_session *session;
 121         struct lttng_channel_extended *channel_attr_extended;
 122
 123         /* Safety net */
 124         assert(channel);
 125         assert(ksession);
 126         assert(ksession->consumer);
 127
 128         consumer = ksession->consumer;
 129         channel_attr_extended = (struct lttng_channel_extended *)
 130                         channel->channel->attr.extended.ptr;
 131
 132         DBG("Kernel consumer adding channel %s to kernel consumer",
 133                         channel->channel->name);
 134
 135         if (monitor) {
 136                 pathname = create_channel_path(consumer, ksession->uid,
 137                                 ksession->gid);
 138         } else {
 139                 /* Empty path. */
 140                 pathname = strdup("");
 141         }
 142         if (!pathname) {
 143                 ret = -1;
 144                 goto error;
 145         }
 146
 147         /* Prep channel message structure */
 148         consumer_init_add_channel_comm_msg(&lkm,
 149                         channel->key,
 150                         ksession->id,
 151                         pathname,
 152                         ksession->uid,
 153                         ksession->gid,
 154                         consumer->net_seq_index,
 155                         channel->channel->name,
 156                         channel->stream_count,
 157                         channel->channel->attr.output,
 158                         CONSUMER_CHANNEL_TYPE_DATA,
 159                         channel->channel->attr.tracefile_size,
 160                         channel->channel->attr.tracefile_count,
 161                         monitor,
 162                         channel->channel->attr.live_timer_interval,
 163                         channel_attr_extended->monitor_timer_interval);
 164
 165         health_code_update();
 166
 167         ret = consumer_send_channel(sock, &lkm);
 168         if (ret < 0) {
 169                 goto error;
 170         }
 171
 172         health_code_update();
 173         rcu_read_lock();
 174         session = session_find_by_id(ksession->id);
 175         assert(session);
 176         assert(pthread_mutex_trylock(&session->lock));
 177         assert(session_trylock_list());
 178
 179         status = notification_thread_command_add_channel(
 180                         notification_thread_handle, session->name,
 181                         ksession->uid, ksession->gid,
 182                         channel->channel->name, channel->key,
 183                         LTTNG_DOMAIN_KERNEL,
 184                         channel->channel->attr.subbuf_size * channel->channel->attr.num_subbuf);
 185         rcu_read_unlock();
 186         if (status != LTTNG_OK) {
 187                 ret = -1;
 188                 goto error;
 189         }
 190
 191         channel->published_to_notification_thread = true;
 192
 193 error:
 194         free(pathname);
 195         return ret;
 196 }
 197
 198 /*
 199  * Sending metadata to the consumer with command ADD_CHANNEL and ADD_STREAM.
 200  *
 201  * The consumer socket lock must be held by the caller.
 202  */
 203 int kernel_consumer_add_metadata(struct consumer_socket *sock,
 204                 struct ltt_kernel_session *ksession, unsigned int monitor)
 205 {
 206         int ret;
 207         char *pathname;
 208         struct lttcomm_consumer_msg lkm;
 209         struct consumer_output *consumer;
 210         struct ltt_session *session;
 211
 212         rcu_read_lock();
 213
 214         /* Safety net */
 215         assert(ksession);
 216         assert(ksession->consumer);
 217         assert(sock);
 218
 219         DBG("Sending metadata %d to kernel consumer",
 220                         ksession->metadata_stream_fd);
 221
 222         /* Get consumer output pointer */
 223         consumer = ksession->consumer;
 224
 225         if (monitor) {
 226                 pathname = create_channel_path(consumer,
 227                                 ksession->uid, ksession->gid);
 228         } else {
 229                 /* Empty path. */
 230                 pathname = strdup("");
 231         }
 232         if (!pathname) {
 233                 ret = -1;
 234                 goto error;
 235         }
 236
 237         session = session_find_by_id(ksession->id);
 238         assert(session);
 239         assert(pthread_mutex_trylock(&session->lock));
 240         assert(session_trylock_list());
 241
 242         /* Prep channel message structure */
 243         consumer_init_add_channel_comm_msg(&lkm,
 244                         ksession->metadata->key,
 245                         ksession->id,
 246                         pathname,
 247                         ksession->uid,
 248                         ksession->gid,
 249                         consumer->net_seq_index,
 250                         DEFAULT_METADATA_NAME,
 251                         1,
 252                         DEFAULT_KERNEL_CHANNEL_OUTPUT,
 253                         CONSUMER_CHANNEL_TYPE_METADATA,
 254                         0, 0,
 255                         monitor, 0, 0);
 256
 257         health_code_update();
 258
 259         ret = consumer_send_channel(sock, &lkm);
 260         if (ret < 0) {
 261                 goto error;
 262         }
 263
 264         health_code_update();
 265
 266         /* Prep stream message structure */
 267         consumer_init_add_stream_comm_msg(&lkm,
 268                         ksession->metadata->key,
 269                         ksession->metadata_stream_fd,
 270                         0 /* CPU: 0 for metadata. */,
 271                         session->current_archive_id);
 272
 273         health_code_update();
 274
 275         /* Send stream and file descriptor */
 276         ret = consumer_send_stream(sock, consumer, &lkm,
 277                         &ksession->metadata_stream_fd, 1);
 278         if (ret < 0) {
 279                 goto error;
 280         }
 281
 282         health_code_update();
 283
 284 error:
 285         rcu_read_unlock();
 286         free(pathname);
 287         return ret;
 288 }
 289
 290 /*
 291  * Sending a single stream to the consumer with command ADD_STREAM.
 292  */
 293 static
 294 int kernel_consumer_add_stream(struct consumer_socket *sock,
 295                 struct ltt_kernel_channel *channel,
 296                 struct ltt_kernel_stream *stream,
 297                 struct ltt_kernel_session *session, unsigned int monitor,
 298                 uint64_t trace_archive_id)
 299 {
 300         int ret;
 301         struct lttcomm_consumer_msg lkm;
 302         struct consumer_output *consumer;
 303
 304         assert(channel);
 305         assert(stream);
 306         assert(session);
 307         assert(session->consumer);
 308         assert(sock);
 309
 310         DBG("Sending stream %d of channel %s to kernel consumer",
 311                         stream->fd, channel->channel->name);
 312
 313         /* Get consumer output pointer */
 314         consumer = session->consumer;
 315
 316         /* Prep stream consumer message */
 317         consumer_init_add_stream_comm_msg(&lkm,
 318                         channel->key,
 319                         stream->fd,
 320                         stream->cpu,
 321                         trace_archive_id);
 322
 323         health_code_update();
 324
 325         /* Send stream and file descriptor */
 326         ret = consumer_send_stream(sock, consumer, &lkm, &stream->fd, 1);
 327         if (ret < 0) {
 328                 goto error;
 329         }
 330
 331         health_code_update();
 332
 333 error:
 334         return ret;
 335 }
 336
 337 /*
 338  * Sending the notification that all streams were sent with STREAMS_SENT.
 339  */
 340 int kernel_consumer_streams_sent(struct consumer_socket *sock,
 341                 struct ltt_kernel_session *session, uint64_t channel_key)
 342 {
 343         int ret;
 344         struct lttcomm_consumer_msg lkm;
 345         struct consumer_output *consumer;
 346
 347         assert(sock);
 348         assert(session);
 349
 350         DBG("Sending streams_sent");
 351         /* Get consumer output pointer */
 352         consumer = session->consumer;
 353
 354         /* Prep stream consumer message */
 355         consumer_init_streams_sent_comm_msg(&lkm,
 356                         LTTNG_CONSUMER_STREAMS_SENT,
 357                         channel_key, consumer->net_seq_index);
 358
 359         health_code_update();
 360
 361         /* Send stream and file descriptor */
 362         ret = consumer_send_msg(sock, &lkm);
 363         if (ret < 0) {
 364                 goto error;
 365         }
 366
 367 error:
 368         return ret;
 369 }
 370
 371 /*
 372  * Send all stream fds of kernel channel to the consumer.
 373  *
 374  * The consumer socket lock must be held by the caller.
 375  */
 376 int kernel_consumer_send_channel_streams(struct consumer_socket *sock,
 377                 struct ltt_kernel_channel *channel, struct ltt_kernel_session *ksession,
 378                 unsigned int monitor)
 379 {
 380         int ret = LTTNG_OK;
 381         struct ltt_kernel_stream *stream;
 382         struct ltt_session *session;
 383
 384         /* Safety net */
 385         assert(channel);
 386         assert(ksession);
 387         assert(ksession->consumer);
 388         assert(sock);
 389
 390         rcu_read_lock();
 391
 392         session = session_find_by_id(ksession->id);
 393         assert(session);
 394         assert(pthread_mutex_trylock(&session->lock));
 395         assert(session_trylock_list());
 396
 397         /* Bail out if consumer is disabled */
 398         if (!ksession->consumer->enabled) {
 399                 ret = LTTNG_OK;
 400                 goto error;
 401         }
 402
 403         DBG("Sending streams of channel %s to kernel consumer",
 404                         channel->channel->name);
 405
 406         if (!channel->sent_to_consumer) {
 407                 ret = kernel_consumer_add_channel(sock, channel, ksession, monitor);
 408                 if (ret < 0) {
 409                         goto error;
 410                 }
 411                 channel->sent_to_consumer = true;
 412         }
 413
 414         /* Send streams */
 415         cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
 416                 if (!stream->fd || stream->sent_to_consumer) {
 417                         continue;
 418                 }
 419
 420                 /* Add stream on the kernel consumer side. */
 421                 ret = kernel_consumer_add_stream(sock, channel, stream,
 422                                 ksession, monitor, session->current_archive_id);
 423                 if (ret < 0) {
 424                         goto error;
 425                 }
 426                 stream->sent_to_consumer = true;
 427         }
 428
 429 error:
 430         rcu_read_unlock();
 431         return ret;
 432 }
 433
 434 /*
 435  * Send all stream fds of the kernel session to the consumer.
 436  *
 437  * The consumer socket lock must be held by the caller.
 438  */
 439 int kernel_consumer_send_session(struct consumer_socket *sock,
 440                 struct ltt_kernel_session *session)
 441 {
 442         int ret, monitor = 0;
 443         struct ltt_kernel_channel *chan;
 444
 445         /* Safety net */
 446         assert(session);
 447         assert(session->consumer);
 448         assert(sock);
 449
 450         /* Bail out if consumer is disabled */
 451         if (!session->consumer->enabled) {
 452                 ret = LTTNG_OK;
 453                 goto error;
 454         }
 455
 456         /* Don't monitor the streams on the consumer if in flight recorder. */
 457         if (session->output_traces) {
 458                 monitor = 1;
 459         }
 460
 461         DBG("Sending session stream to kernel consumer");
 462
 463         if (session->metadata_stream_fd >= 0 && session->metadata) {
 464                 ret = kernel_consumer_add_metadata(sock, session, monitor);
 465                 if (ret < 0) {
 466                         goto error;
 467                 }
 468         }
 469
 470         /* Send channel and streams of it */
 471         cds_list_for_each_entry(chan, &session->channel_list.head, list) {
 472                 ret = kernel_consumer_send_channel_streams(sock, chan, session,
 473                                 monitor);
 474                 if (ret < 0) {
 475                         goto error;
 476                 }
 477                 if (monitor) {
 478                         /*
 479                          * Inform the relay that all the streams for the
 480                          * channel were sent.
 481                          */
 482                         ret = kernel_consumer_streams_sent(sock, session, chan->key);
 483                         if (ret < 0) {
 484                                 goto error;
 485                         }
 486                 }
 487         }
 488
 489         DBG("Kernel consumer FDs of metadata and channel streams sent");
 490
 491         session->consumer_fds_sent = 1;
 492         return 0;
 493
 494 error:
 495         return ret;
 496 }
 497
 498 int kernel_consumer_destroy_channel(struct consumer_socket *socket,
 499                 struct ltt_kernel_channel *channel)
 500 {
 501         int ret;
 502         struct lttcomm_consumer_msg msg;
 503
 504         assert(channel);
 505         assert(socket);
 506
 507         DBG("Sending kernel consumer destroy channel key %" PRIu64, channel->key);
 508
 509         memset(&msg, 0, sizeof(msg));
 510         msg.cmd_type = LTTNG_CONSUMER_DESTROY_CHANNEL;
 511         msg.u.destroy_channel.key = channel->key;
 512
 513         pthread_mutex_lock(socket->lock);
 514         health_code_update();
 515
 516         ret = consumer_send_msg(socket, &msg);
 517         if (ret < 0) {
 518                 goto error;
 519         }
 520
 521 error:
 522         health_code_update();
 523         pthread_mutex_unlock(socket->lock);
 524         return ret;
 525 }
 526
 527 int kernel_consumer_destroy_metadata(struct consumer_socket *socket,
 528                 struct ltt_kernel_metadata *metadata)
 529 {
 530         int ret;
 531         struct lttcomm_consumer_msg msg;
 532
 533         assert(metadata);
 534         assert(socket);
 535
 536         DBG("Sending kernel consumer destroy channel key %" PRIu64, metadata->key);
 537
 538         memset(&msg, 0, sizeof(msg));
 539         msg.cmd_type = LTTNG_CONSUMER_DESTROY_CHANNEL;
 540         msg.u.destroy_channel.key = metadata->key;
 541
 542         pthread_mutex_lock(socket->lock);
 543         health_code_update();
 544
 545         ret = consumer_send_msg(socket, &msg);
 546         if (ret < 0) {
 547                 goto error;
 548         }
 549
 550 error:
 551         health_code_update();
 552         pthread_mutex_unlock(socket->lock);
 553         return ret;
 554 }