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
 177         status = notification_thread_command_add_channel(
 178                         notification_thread_handle, session->name,
 179                         ksession->uid, ksession->gid,
 180                         channel->channel->name, channel->key,
 181                         LTTNG_DOMAIN_KERNEL,
 182                         channel->channel->attr.subbuf_size * channel->channel->attr.num_subbuf);
 183         rcu_read_unlock();
 184         if (status != LTTNG_OK) {
 185                 ret = -1;
 186                 goto error;
 187         }
 188
 189         channel->published_to_notification_thread = true;
 190
 191 error:
 192         free(pathname);
 193         return ret;
 194 }
 195
 196 /*
 197  * Sending metadata to the consumer with command ADD_CHANNEL and ADD_STREAM.
 198  *
 199  * The consumer socket lock must be held by the caller.
 200  */
 201 int kernel_consumer_add_metadata(struct consumer_socket *sock,
 202                 struct ltt_kernel_session *session, unsigned int monitor)
 203 {
 204         int ret;
 205         char *pathname;
 206         struct lttcomm_consumer_msg lkm;
 207         struct consumer_output *consumer;
 208
 209         /* Safety net */
 210         assert(session);
 211         assert(session->consumer);
 212         assert(sock);
 213
 214         DBG("Sending metadata %d to kernel consumer", session->metadata_stream_fd);
 215
 216         /* Get consumer output pointer */
 217         consumer = session->consumer;
 218
 219         if (monitor) {
 220                 pathname = create_channel_path(consumer, session->uid, session->gid);
 221         } else {
 222                 /* Empty path. */
 223                 pathname = strdup("");
 224         }
 225         if (!pathname) {
 226                 ret = -1;
 227                 goto error;
 228         }
 229
 230         /* Prep channel message structure */
 231         consumer_init_add_channel_comm_msg(&lkm,
 232                         session->metadata->key,
 233                         session->id,
 234                         pathname,
 235                         session->uid,
 236                         session->gid,
 237                         consumer->net_seq_index,
 238                         DEFAULT_METADATA_NAME,
 239                         1,
 240                         DEFAULT_KERNEL_CHANNEL_OUTPUT,
 241                         CONSUMER_CHANNEL_TYPE_METADATA,
 242                         0, 0,
 243                         monitor, 0, 0);
 244
 245         health_code_update();
 246
 247         ret = consumer_send_channel(sock, &lkm);
 248         if (ret < 0) {
 249                 goto error;
 250         }
 251
 252         health_code_update();
 253
 254         /* Prep stream message structure */
 255         consumer_init_stream_comm_msg(&lkm,
 256                         LTTNG_CONSUMER_ADD_STREAM,
 257                         session->metadata->key,
 258                         session->metadata_stream_fd,
 259                         0); /* CPU: 0 for metadata. */
 260
 261         health_code_update();
 262
 263         /* Send stream and file descriptor */
 264         ret = consumer_send_stream(sock, consumer, &lkm,
 265                         &session->metadata_stream_fd, 1);
 266         if (ret < 0) {
 267                 goto error;
 268         }
 269
 270         health_code_update();
 271
 272 error:
 273         free(pathname);
 274         return ret;
 275 }
 276
 277 /*
 278  * Sending a single stream to the consumer with command ADD_STREAM.
 279  */
 280 int kernel_consumer_add_stream(struct consumer_socket *sock,
 281                 struct ltt_kernel_channel *channel, struct ltt_kernel_stream *stream,
 282                 struct ltt_kernel_session *session, unsigned int monitor)
 283 {
 284         int ret;
 285         struct lttcomm_consumer_msg lkm;
 286         struct consumer_output *consumer;
 287
 288         assert(channel);
 289         assert(stream);
 290         assert(session);
 291         assert(session->consumer);
 292         assert(sock);
 293
 294         DBG("Sending stream %d of channel %s to kernel consumer",
 295                         stream->fd, channel->channel->name);
 296
 297         /* Get consumer output pointer */
 298         consumer = session->consumer;
 299
 300         /* Prep stream consumer message */
 301         consumer_init_stream_comm_msg(&lkm,
 302                         LTTNG_CONSUMER_ADD_STREAM,
 303                         channel->key,
 304                         stream->fd,
 305                         stream->cpu);
 306
 307         health_code_update();
 308
 309         /* Send stream and file descriptor */
 310         ret = consumer_send_stream(sock, consumer, &lkm, &stream->fd, 1);
 311         if (ret < 0) {
 312                 goto error;
 313         }
 314
 315         health_code_update();
 316
 317 error:
 318         return ret;
 319 }
 320
 321 /*
 322  * Sending the notification that all streams were sent with STREAMS_SENT.
 323  */
 324 int kernel_consumer_streams_sent(struct consumer_socket *sock,
 325                 struct ltt_kernel_session *session, uint64_t channel_key)
 326 {
 327         int ret;
 328         struct lttcomm_consumer_msg lkm;
 329         struct consumer_output *consumer;
 330
 331         assert(sock);
 332         assert(session);
 333
 334         DBG("Sending streams_sent");
 335         /* Get consumer output pointer */
 336         consumer = session->consumer;
 337
 338         /* Prep stream consumer message */
 339         consumer_init_streams_sent_comm_msg(&lkm,
 340                         LTTNG_CONSUMER_STREAMS_SENT,
 341                         channel_key, consumer->net_seq_index);
 342
 343         health_code_update();
 344
 345         /* Send stream and file descriptor */
 346         ret = consumer_send_msg(sock, &lkm);
 347         if (ret < 0) {
 348                 goto error;
 349         }
 350
 351 error:
 352         return ret;
 353 }
 354
 355 /*
 356  * Send all stream fds of kernel channel to the consumer.
 357  *
 358  * The consumer socket lock must be held by the caller.
 359  */
 360 int kernel_consumer_send_channel_stream(struct consumer_socket *sock,
 361                 struct ltt_kernel_channel *channel, struct ltt_kernel_session *session,
 362                 unsigned int monitor)
 363 {
 364         int ret = LTTNG_OK;
 365         struct ltt_kernel_stream *stream;
 366
 367         /* Safety net */
 368         assert(channel);
 369         assert(session);
 370         assert(session->consumer);
 371         assert(sock);
 372
 373         /* Bail out if consumer is disabled */
 374         if (!session->consumer->enabled) {
 375                 ret = LTTNG_OK;
 376                 goto error;
 377         }
 378
 379         DBG("Sending streams of channel %s to kernel consumer",
 380                         channel->channel->name);
 381
 382         if (!channel->sent_to_consumer) {
 383                 ret = kernel_consumer_add_channel(sock, channel, session, monitor);
 384                 if (ret < 0) {
 385                         goto error;
 386                 }
 387                 channel->sent_to_consumer = true;
 388         }
 389
 390         /* Send streams */
 391         cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
 392                 if (!stream->fd || stream->sent_to_consumer) {
 393                         continue;
 394                 }
 395
 396                 /* Add stream on the kernel consumer side. */
 397                 ret = kernel_consumer_add_stream(sock, channel, stream, session,
 398                                 monitor);
 399                 if (ret < 0) {
 400                         goto error;
 401                 }
 402                 stream->sent_to_consumer = true;
 403         }
 404
 405 error:
 406         return ret;
 407 }
 408
 409 /*
 410  * Send all stream fds of the kernel session to the consumer.
 411  *
 412  * The consumer socket lock must be held by the caller.
 413  */
 414 int kernel_consumer_send_session(struct consumer_socket *sock,
 415                 struct ltt_kernel_session *session)
 416 {
 417         int ret, monitor = 0;
 418         struct ltt_kernel_channel *chan;
 419
 420         /* Safety net */
 421         assert(session);
 422         assert(session->consumer);
 423         assert(sock);
 424
 425         /* Bail out if consumer is disabled */
 426         if (!session->consumer->enabled) {
 427                 ret = LTTNG_OK;
 428                 goto error;
 429         }
 430
 431         /* Don't monitor the streams on the consumer if in flight recorder. */
 432         if (session->output_traces) {
 433                 monitor = 1;
 434         }
 435
 436         DBG("Sending session stream to kernel consumer");
 437
 438         if (session->metadata_stream_fd >= 0 && session->metadata) {
 439                 ret = kernel_consumer_add_metadata(sock, session, monitor);
 440                 if (ret < 0) {
 441                         goto error;
 442                 }
 443         }
 444
 445         /* Send channel and streams of it */
 446         cds_list_for_each_entry(chan, &session->channel_list.head, list) {
 447                 ret = kernel_consumer_send_channel_stream(sock, chan, session,
 448                                 monitor);
 449                 if (ret < 0) {
 450                         goto error;
 451                 }
 452                 if (monitor) {
 453                         /*
 454                          * Inform the relay that all the streams for the
 455                          * channel were sent.
 456                          */
 457                         ret = kernel_consumer_streams_sent(sock, session, chan->key);
 458                         if (ret < 0) {
 459                                 goto error;
 460                         }
 461                 }
 462         }
 463
 464         DBG("Kernel consumer FDs of metadata and channel streams sent");
 465
 466         session->consumer_fds_sent = 1;
 467         return 0;
 468
 469 error:
 470         return ret;
 471 }
 472
 473 int kernel_consumer_destroy_channel(struct consumer_socket *socket,
 474                 struct ltt_kernel_channel *channel)
 475 {
 476         int ret;
 477         struct lttcomm_consumer_msg msg;
 478
 479         assert(channel);
 480         assert(socket);
 481
 482         DBG("Sending kernel consumer destroy channel key %" PRIu64, channel->key);
 483
 484         memset(&msg, 0, sizeof(msg));
 485         msg.cmd_type = LTTNG_CONSUMER_DESTROY_CHANNEL;
 486         msg.u.destroy_channel.key = channel->key;
 487
 488         pthread_mutex_lock(socket->lock);
 489         health_code_update();
 490
 491         ret = consumer_send_msg(socket, &msg);
 492         if (ret < 0) {
 493                 goto error;
 494         }
 495
 496 error:
 497         health_code_update();
 498         pthread_mutex_unlock(socket->lock);
 499         return ret;
 500 }
 501
 502 int kernel_consumer_destroy_metadata(struct consumer_socket *socket,
 503                 struct ltt_kernel_metadata *metadata)
 504 {
 505         int ret;
 506         struct lttcomm_consumer_msg msg;
 507
 508         assert(metadata);
 509         assert(socket);
 510
 511         DBG("Sending kernel consumer destroy channel key %" PRIu64, metadata->key);
 512
 513         memset(&msg, 0, sizeof(msg));
 514         msg.cmd_type = LTTNG_CONSUMER_DESTROY_CHANNEL;
 515         msg.u.destroy_channel.key = metadata->key;
 516
 517         pthread_mutex_lock(socket->lock);
 518         health_code_update();
 519
 520         ret = consumer_send_msg(socket, &msg);
 521         if (ret < 0) {
 522                 goto error;
 523         }
 524
 525 error:
 526         health_code_update();
 527         pthread_mutex_unlock(socket->lock);
 528         return ret;
 529 }