src/bin/lttng-sessiond/cmd.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 _GNU_SOURCE
  19 #include <assert.h>
  20 #include <urcu/list.h>
  21 #include <urcu/uatomic.h>
  22
  23 #include <common/defaults.h>
  24 #include <common/common.h>
  25 #include <common/sessiond-comm/sessiond-comm.h>
  26 #include <common/relayd/relayd.h>
  27
  28 #include "channel.h"
  29 #include "consumer.h"
  30 #include "event.h"
  31 #include "health.h"
  32 #include "kernel.h"
  33 #include "kernel-consumer.h"
  34 #include "lttng-sessiond.h"
  35 #include "utils.h"
  36
  37 #include "cmd.h"
  38
  39 /*
  40  * Used to keep a unique index for each relayd socket created where this value
  41  * is associated with streams on the consumer so it can match the right relayd
  42  * to send to. It must be accessed with the relayd_net_seq_idx_lock
  43  * held.
  44  */
  45 static pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
  46 static uint64_t relayd_net_seq_idx;
  47
  48 /*
  49  * Create a session path used by list_lttng_sessions for the case that the
  50  * session consumer is on the network.
  51  */
  52 static int build_network_session_path(char *dst, size_t size,
  53                 struct ltt_session *session)
  54 {
  55         int ret, kdata_port, udata_port;
  56         struct lttng_uri *kuri = NULL, *uuri = NULL, *uri = NULL;
  57         char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
  58
  59         assert(session);
  60         assert(dst);
  61
  62         memset(tmp_urls, 0, sizeof(tmp_urls));
  63         memset(tmp_uurl, 0, sizeof(tmp_uurl));
  64
  65         kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
  66
  67         if (session->kernel_session && session->kernel_session->consumer) {
  68                 kuri = &session->kernel_session->consumer->dst.net.control;
  69                 kdata_port = session->kernel_session->consumer->dst.net.data.port;
  70         }
  71
  72         if (session->ust_session && session->ust_session->consumer) {
  73                 uuri = &session->ust_session->consumer->dst.net.control;
  74                 udata_port = session->ust_session->consumer->dst.net.data.port;
  75         }
  76
  77         if (uuri == NULL && kuri == NULL) {
  78                 uri = &session->consumer->dst.net.control;
  79                 kdata_port = session->consumer->dst.net.data.port;
  80         } else if (kuri && uuri) {
  81                 ret = uri_compare(kuri, uuri);
  82                 if (ret) {
  83                         /* Not Equal */
  84                         uri = kuri;
  85                         /* Build uuri URL string */
  86                         ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
  87                         if (ret < 0) {
  88                                 goto error;
  89                         }
  90                 } else {
  91                         uri = kuri;
  92                 }
  93         } else if (kuri && uuri == NULL) {
  94                 uri = kuri;
  95         } else if (uuri && kuri == NULL) {
  96                 uri = uuri;
  97         }
  98
  99         ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
 100         if (ret < 0) {
 101                 goto error;
 102         }
 103
 104         /*
 105          * Do we have a UST url set. If yes, this means we have both kernel and UST
 106          * to print.
 107          */
 108         if (*tmp_uurl != '\0') {
 109                 ret = snprintf(dst, size, "[K]: %s [data: %d] -- [U]: %s [data: %d]",
 110                                 tmp_urls, kdata_port, tmp_uurl, udata_port);
 111         } else {
 112                 int dport;
 113                 if (kuri) {
 114                         dport = kdata_port;
 115                 } else {
 116                         /* No kernel URI, use the UST port. */
 117                         dport = udata_port;
 118                 }
 119                 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
 120         }
 121
 122 error:
 123         return ret;
 124 }
 125
 126 /*
 127  * Fill lttng_channel array of all channels.
 128  */
 129 static void list_lttng_channels(int domain, struct ltt_session *session,
 130                 struct lttng_channel *channels)
 131 {
 132         int i = 0;
 133         struct ltt_kernel_channel *kchan;
 134
 135         DBG("Listing channels for session %s", session->name);
 136
 137         switch (domain) {
 138         case LTTNG_DOMAIN_KERNEL:
 139                 /* Kernel channels */
 140                 if (session->kernel_session != NULL) {
 141                         cds_list_for_each_entry(kchan,
 142                                         &session->kernel_session->channel_list.head, list) {
 143                                 /* Copy lttng_channel struct to array */
 144                                 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
 145                                 channels[i].enabled = kchan->enabled;
 146                                 i++;
 147                         }
 148                 }
 149                 break;
 150         case LTTNG_DOMAIN_UST:
 151         {
 152                 struct lttng_ht_iter iter;
 153                 struct ltt_ust_channel *uchan;
 154
 155                 rcu_read_lock();
 156                 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
 157                                 &iter.iter, uchan, node.node) {
 158                         strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
 159                         channels[i].attr.overwrite = uchan->attr.overwrite;
 160                         channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
 161                         channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
 162                         channels[i].attr.switch_timer_interval =
 163                                 uchan->attr.switch_timer_interval;
 164                         channels[i].attr.read_timer_interval =
 165                                 uchan->attr.read_timer_interval;
 166                         channels[i].enabled = uchan->enabled;
 167                         switch (uchan->attr.output) {
 168                         case LTTNG_UST_MMAP:
 169                         default:
 170                                 channels[i].attr.output = LTTNG_EVENT_MMAP;
 171                                 break;
 172                         }
 173                         i++;
 174                 }
 175                 rcu_read_unlock();
 176                 break;
 177         }
 178         default:
 179                 break;
 180         }
 181 }
 182
 183 /*
 184  * Create a list of ust global domain events.
 185  */
 186 static int list_lttng_ust_global_events(char *channel_name,
 187                 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
 188 {
 189         int i = 0, ret = 0;
 190         unsigned int nb_event = 0;
 191         struct lttng_ht_iter iter;
 192         struct lttng_ht_node_str *node;
 193         struct ltt_ust_channel *uchan;
 194         struct ltt_ust_event *uevent;
 195         struct lttng_event *tmp;
 196
 197         DBG("Listing UST global events for channel %s", channel_name);
 198
 199         rcu_read_lock();
 200
 201         lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
 202         node = lttng_ht_iter_get_node_str(&iter);
 203         if (node == NULL) {
 204                 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
 205                 goto error;
 206         }
 207
 208         uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
 209
 210         nb_event += lttng_ht_get_count(uchan->events);
 211
 212         if (nb_event == 0) {
 213                 ret = nb_event;
 214                 goto error;
 215         }
 216
 217         DBG3("Listing UST global %d events", nb_event);
 218
 219         tmp = zmalloc(nb_event * sizeof(struct lttng_event));
 220         if (tmp == NULL) {
 221                 ret = LTTNG_ERR_FATAL;
 222                 goto error;
 223         }
 224
 225         cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
 226                 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
 227                 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
 228                 tmp[i].enabled = uevent->enabled;
 229
 230                 switch (uevent->attr.instrumentation) {
 231                 case LTTNG_UST_TRACEPOINT:
 232                         tmp[i].type = LTTNG_EVENT_TRACEPOINT;
 233                         break;
 234                 case LTTNG_UST_PROBE:
 235                         tmp[i].type = LTTNG_EVENT_PROBE;
 236                         break;
 237                 case LTTNG_UST_FUNCTION:
 238                         tmp[i].type = LTTNG_EVENT_FUNCTION;
 239                         break;
 240                 }
 241
 242                 tmp[i].loglevel = uevent->attr.loglevel;
 243                 switch (uevent->attr.loglevel_type) {
 244                 case LTTNG_UST_LOGLEVEL_ALL:
 245                         tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
 246                         break;
 247                 case LTTNG_UST_LOGLEVEL_RANGE:
 248                         tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
 249                         break;
 250                 case LTTNG_UST_LOGLEVEL_SINGLE:
 251                         tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
 252                         break;
 253                 }
 254                 if (uevent->filter) {
 255                         tmp[i].filter = 1;
 256                 }
 257                 i++;
 258         }
 259
 260         ret = nb_event;
 261         *events = tmp;
 262
 263 error:
 264         rcu_read_unlock();
 265         return ret;
 266 }
 267
 268 /*
 269  * Fill lttng_event array of all kernel events in the channel.
 270  */
 271 static int list_lttng_kernel_events(char *channel_name,
 272                 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
 273 {
 274         int i = 0, ret;
 275         unsigned int nb_event;
 276         struct ltt_kernel_event *event;
 277         struct ltt_kernel_channel *kchan;
 278
 279         kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
 280         if (kchan == NULL) {
 281                 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
 282                 goto error;
 283         }
 284
 285         nb_event = kchan->event_count;
 286
 287         DBG("Listing events for channel %s", kchan->channel->name);
 288
 289         if (nb_event == 0) {
 290                 goto end;
 291         }
 292
 293         *events = zmalloc(nb_event * sizeof(struct lttng_event));
 294         if (*events == NULL) {
 295                 ret = LTTNG_ERR_FATAL;
 296                 goto error;
 297         }
 298
 299         /* Kernel channels */
 300         cds_list_for_each_entry(event, &kchan->events_list.head , list) {
 301                 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
 302                 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
 303                 (*events)[i].enabled = event->enabled;
 304
 305                 switch (event->event->instrumentation) {
 306                 case LTTNG_KERNEL_TRACEPOINT:
 307                         (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
 308                         break;
 309                 case LTTNG_KERNEL_KRETPROBE:
 310                         (*events)[i].type = LTTNG_EVENT_FUNCTION;
 311                         memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
 312                                         sizeof(struct lttng_kernel_kprobe));
 313                         break;
 314                 case LTTNG_KERNEL_KPROBE:
 315                         (*events)[i].type = LTTNG_EVENT_PROBE;
 316                         memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
 317                                         sizeof(struct lttng_kernel_kprobe));
 318                         break;
 319                 case LTTNG_KERNEL_FUNCTION:
 320                         (*events)[i].type = LTTNG_EVENT_FUNCTION;
 321                         memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
 322                                         sizeof(struct lttng_kernel_function));
 323                         break;
 324                 case LTTNG_KERNEL_NOOP:
 325                         (*events)[i].type = LTTNG_EVENT_NOOP;
 326                         break;
 327                 case LTTNG_KERNEL_SYSCALL:
 328                         (*events)[i].type = LTTNG_EVENT_SYSCALL;
 329                         break;
 330                 case LTTNG_KERNEL_ALL:
 331                         assert(0);
 332                         break;
 333                 }
 334                 i++;
 335         }
 336
 337 end:
 338         return nb_event;
 339
 340 error:
 341         /* Negate the error code to differentiate the size from an error */
 342         return -ret;
 343 }
 344
 345 /*
 346  * Add URI so the consumer output object. Set the correct path depending on the
 347  * domain adding the default trace directory.
 348  */
 349 static int add_uri_to_consumer(struct consumer_output *consumer,
 350                 struct lttng_uri *uri, int domain, const char *session_name)
 351 {
 352         int ret = LTTNG_OK;
 353         const char *default_trace_dir;
 354
 355         assert(uri);
 356
 357         if (consumer == NULL) {
 358                 DBG("No consumer detected. Don't add URI. Stopping.");
 359                 ret = LTTNG_ERR_NO_CONSUMER;
 360                 goto error;
 361         }
 362
 363         switch (domain) {
 364         case LTTNG_DOMAIN_KERNEL:
 365                 default_trace_dir = DEFAULT_KERNEL_TRACE_DIR;
 366                 break;
 367         case LTTNG_DOMAIN_UST:
 368                 default_trace_dir = DEFAULT_UST_TRACE_DIR;
 369                 break;
 370         default:
 371                 /*
 372                  * This case is possible is we try to add the URI to the global tracing
 373                  * session consumer object which in this case there is no subdir.
 374                  */
 375                 default_trace_dir = "";
 376         }
 377
 378         switch (uri->dtype) {
 379         case LTTNG_DST_IPV4:
 380         case LTTNG_DST_IPV6:
 381                 DBG2("Setting network URI to consumer");
 382
 383                 consumer->type = CONSUMER_DST_NET;
 384
 385                 if ((uri->stype == LTTNG_STREAM_CONTROL &&
 386                                 consumer->dst.net.control_isset) ||
 387                                 (uri->stype == LTTNG_STREAM_DATA &&
 388                                 consumer->dst.net.data_isset)) {
 389                         ret = LTTNG_ERR_URL_EXIST;
 390                         goto error;
 391                 }
 392
 393                 /* Set URI into consumer output object */
 394                 ret = consumer_set_network_uri(consumer, uri);
 395                 if (ret < 0) {
 396                         ret = LTTNG_ERR_FATAL;
 397                         goto error;
 398                 } else if (ret == 1) {
 399                         /*
 400                          * URI was the same in the consumer so we do not append the subdir
 401                          * again so to not duplicate output dir.
 402                          */
 403                         goto error;
 404                 }
 405
 406                 if (uri->stype == LTTNG_STREAM_CONTROL && strlen(uri->subdir) == 0) {
 407                         ret = consumer_set_subdir(consumer, session_name);
 408                         if (ret < 0) {
 409                                 ret = LTTNG_ERR_FATAL;
 410                                 goto error;
 411                         }
 412                 }
 413
 414                 if (uri->stype == LTTNG_STREAM_CONTROL) {
 415                         /* On a new subdir, reappend the default trace dir. */
 416                         strncat(consumer->subdir, default_trace_dir,
 417                                         sizeof(consumer->subdir) - strlen(consumer->subdir) - 1);
 418                         DBG3("Append domain trace name to subdir %s", consumer->subdir);
 419                 }
 420
 421                 break;
 422         case LTTNG_DST_PATH:
 423                 DBG2("Setting trace directory path from URI to %s", uri->dst.path);
 424                 memset(consumer->dst.trace_path, 0,
 425                                 sizeof(consumer->dst.trace_path));
 426                 strncpy(consumer->dst.trace_path, uri->dst.path,
 427                                 sizeof(consumer->dst.trace_path));
 428                 /* Append default trace dir */
 429                 strncat(consumer->dst.trace_path, default_trace_dir,
 430                                 sizeof(consumer->dst.trace_path) -
 431                                 strlen(consumer->dst.trace_path) - 1);
 432                 /* Flag consumer as local. */
 433                 consumer->type = CONSUMER_DST_LOCAL;
 434                 break;
 435         }
 436
 437 error:
 438         return ret;
 439 }
 440
 441 /*
 442  * Init tracing by creating trace directory and sending fds kernel consumer.
 443  */
 444 static int init_kernel_tracing(struct ltt_kernel_session *session)
 445 {
 446         int ret = 0;
 447         struct lttng_ht_iter iter;
 448         struct consumer_socket *socket;
 449
 450         assert(session);
 451
 452         rcu_read_lock();
 453
 454         if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
 455                 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
 456                                 socket, node.node) {
 457                         /* Code flow error */
 458                         assert(socket->fd >= 0);
 459
 460                         pthread_mutex_lock(socket->lock);
 461                         ret = kernel_consumer_send_session(socket, session);
 462                         pthread_mutex_unlock(socket->lock);
 463                         if (ret < 0) {
 464                                 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
 465                                 goto error;
 466                         }
 467                 }
 468         }
 469
 470 error:
 471         rcu_read_unlock();
 472         return ret;
 473 }
 474
 475 /*
 476  * Create a socket to the relayd using the URI.
 477  *
 478  * On success, the relayd_sock pointer is set to the created socket.
 479  * Else, it's stays untouched and a lttcomm error code is returned.
 480  */
 481 static int create_connect_relayd(struct consumer_output *output,
 482                 const char *session_name, struct lttng_uri *uri,
 483                 struct lttcomm_sock **relayd_sock)
 484 {
 485         int ret;
 486         struct lttcomm_sock *sock;
 487
 488         /* Create socket object from URI */
 489         sock = lttcomm_alloc_sock_from_uri(uri);
 490         if (sock == NULL) {
 491                 ret = LTTNG_ERR_FATAL;
 492                 goto error;
 493         }
 494
 495         ret = lttcomm_create_sock(sock);
 496         if (ret < 0) {
 497                 ret = LTTNG_ERR_FATAL;
 498                 goto error;
 499         }
 500
 501         /*
 502          * Connect to relayd so we can proceed with a session creation. This call
 503          * can possibly block for an arbitrary amount of time to set the health
 504          * state to be in poll execution.
 505          */
 506         health_poll_entry();
 507         ret = relayd_connect(sock);
 508         health_poll_exit();
 509         if (ret < 0) {
 510                 ERR("Unable to reach lttng-relayd");
 511                 ret = LTTNG_ERR_RELAYD_CONNECT_FAIL;
 512                 goto free_sock;
 513         }
 514
 515         /* Create socket for control stream. */
 516         if (uri->stype == LTTNG_STREAM_CONTROL) {
 517                 DBG3("Creating relayd stream socket from URI");
 518
 519                 /* Check relayd version */
 520                 ret = relayd_version_check(sock, RELAYD_VERSION_COMM_MAJOR,
 521                                 RELAYD_VERSION_COMM_MINOR);
 522                 if (ret < 0) {
 523                         ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
 524                         goto close_sock;
 525                 }
 526         } else if (uri->stype == LTTNG_STREAM_DATA) {
 527                 DBG3("Creating relayd data socket from URI");
 528         } else {
 529                 /* Command is not valid */
 530                 ERR("Relayd invalid stream type: %d", uri->stype);
 531                 ret = LTTNG_ERR_INVALID;
 532                 goto close_sock;
 533         }
 534
 535         *relayd_sock = sock;
 536
 537         return LTTNG_OK;
 538
 539 close_sock:
 540         if (sock) {
 541                 (void) relayd_close(sock);
 542         }
 543 free_sock:
 544         if (sock) {
 545                 lttcomm_destroy_sock(sock);
 546         }
 547 error:
 548         return ret;
 549 }
 550
 551 /*
 552  * Connect to the relayd using URI and send the socket to the right consumer.
 553  */
 554 static int send_consumer_relayd_socket(int domain, struct ltt_session *session,
 555                 struct lttng_uri *relayd_uri, struct consumer_output *consumer,
 556                 struct consumer_socket *consumer_sock)
 557 {
 558         int ret;
 559         struct lttcomm_sock *sock = NULL;
 560
 561         /* Connect to relayd and make version check if uri is the control. */
 562         ret = create_connect_relayd(consumer, session->name, relayd_uri, &sock);
 563         if (ret != LTTNG_OK) {
 564                 goto close_sock;
 565         }
 566
 567         /* If the control socket is connected, network session is ready */
 568         if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
 569                 session->net_handle = 1;
 570         }
 571
 572         /* Set the network sequence index if not set. */
 573         if (consumer->net_seq_index == (uint64_t) -1ULL) {
 574                 pthread_mutex_lock(&relayd_net_seq_idx_lock);
 575                 /*
 576                  * Increment net_seq_idx because we are about to transfer the
 577                  * new relayd socket to the consumer.
 578                  * Assign unique key so the consumer can match streams.
 579                  */
 580                 consumer->net_seq_index = ++relayd_net_seq_idx;
 581                 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
 582         }
 583
 584         /* Send relayd socket to consumer. */
 585         ret = consumer_send_relayd_socket(consumer_sock, sock,
 586                         consumer, relayd_uri->stype, session->id);
 587         if (ret < 0) {
 588                 ret = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
 589                 goto close_sock;
 590         }
 591
 592         /* Flag that the corresponding socket was sent. */
 593         if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
 594                 consumer_sock->control_sock_sent = 1;
 595         } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
 596                 consumer_sock->data_sock_sent = 1;
 597         }
 598
 599         ret = LTTNG_OK;
 600
 601         /*
 602          * Close socket which was dup on the consumer side. The session daemon does
 603          * NOT keep track of the relayd socket(s) once transfer to the consumer.
 604          */
 605
 606 close_sock:
 607         if (sock) {
 608                 (void) relayd_close(sock);
 609                 lttcomm_destroy_sock(sock);
 610         }
 611
 612         if (ret != LTTNG_OK) {
 613                 /*
 614                  * On error, nullify the consumer sequence index so streams are not
 615                  * associated with it once sent to the consumer.
 616                  */
 617                 uatomic_set(&consumer->net_seq_index, -1);
 618         }
 619
 620         return ret;
 621 }
 622
 623 /*
 624  * Send both relayd sockets to a specific consumer and domain.  This is a
 625  * helper function to facilitate sending the information to the consumer for a
 626  * session.
 627  */
 628 static int send_consumer_relayd_sockets(int domain,
 629                 struct ltt_session *session, struct consumer_output *consumer,
 630                 struct consumer_socket *sock)
 631 {
 632         int ret = LTTNG_OK;
 633
 634         assert(session);
 635         assert(consumer);
 636
 637         /* Sending control relayd socket. */
 638         if (!sock->control_sock_sent) {
 639                 ret = send_consumer_relayd_socket(domain, session,
 640                                 &consumer->dst.net.control, consumer, sock);
 641                 if (ret != LTTNG_OK) {
 642                         goto error;
 643                 }
 644         }
 645
 646         /* Sending data relayd socket. */
 647         if (!sock->data_sock_sent) {
 648                 ret = send_consumer_relayd_socket(domain, session,
 649                                 &consumer->dst.net.data, consumer, sock);
 650                 if (ret != LTTNG_OK) {
 651                         goto error;
 652                 }
 653         }
 654
 655 error:
 656         return ret;
 657 }
 658
 659 /*
 660  * Setup relayd connections for a tracing session. First creates the socket to
 661  * the relayd and send them to the right domain consumer. Consumer type MUST be
 662  * network.
 663  */
 664 int cmd_setup_relayd(struct ltt_session *session)
 665 {
 666         int ret = LTTNG_OK;
 667         struct ltt_ust_session *usess;
 668         struct ltt_kernel_session *ksess;
 669         struct consumer_socket *socket;
 670         struct lttng_ht_iter iter;
 671
 672         assert(session);
 673
 674         usess = session->ust_session;
 675         ksess = session->kernel_session;
 676
 677         DBG("Setting relayd for session %s", session->name);
 678
 679         rcu_read_lock();
 680
 681         if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
 682                         && usess->consumer->enabled) {
 683                 /* For each consumer socket, send relayd sockets */
 684                 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
 685                                 socket, node.node) {
 686                         /* Code flow error */
 687                         assert(socket->fd >= 0);
 688
 689                         pthread_mutex_lock(socket->lock);
 690                         ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session,
 691                                         usess->consumer, socket);
 692                         pthread_mutex_unlock(socket->lock);
 693                         if (ret != LTTNG_OK) {
 694                                 goto error;
 695                         }
 696                 }
 697         }
 698
 699         if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
 700                         && ksess->consumer->enabled) {
 701                 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
 702                                 socket, node.node) {
 703                         /* Code flow error */
 704                         assert(socket->fd >= 0);
 705
 706                         pthread_mutex_lock(socket->lock);
 707                         ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session,
 708                                         ksess->consumer, socket);
 709                         pthread_mutex_unlock(socket->lock);
 710                         if (ret != LTTNG_OK) {
 711                                 goto error;
 712                         }
 713                 }
 714         }
 715
 716 error:
 717         rcu_read_unlock();
 718         return ret;
 719 }
 720
 721 /*
 722  * Start a kernel session by opening all necessary streams.
 723  */
 724 static int start_kernel_session(struct ltt_kernel_session *ksess, int wpipe)
 725 {
 726         int ret;
 727         struct ltt_kernel_channel *kchan;
 728
 729         /* Open kernel metadata */
 730         if (ksess->metadata == NULL) {
 731                 ret = kernel_open_metadata(ksess);
 732                 if (ret < 0) {
 733                         ret = LTTNG_ERR_KERN_META_FAIL;
 734                         goto error;
 735                 }
 736         }
 737
 738         /* Open kernel metadata stream */
 739         if (ksess->metadata_stream_fd < 0) {
 740                 ret = kernel_open_metadata_stream(ksess);
 741                 if (ret < 0) {
 742                         ERR("Kernel create metadata stream failed");
 743                         ret = LTTNG_ERR_KERN_STREAM_FAIL;
 744                         goto error;
 745                 }
 746         }
 747
 748         /* For each channel */
 749         cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
 750                 if (kchan->stream_count == 0) {
 751                         ret = kernel_open_channel_stream(kchan);
 752                         if (ret < 0) {
 753                                 ret = LTTNG_ERR_KERN_STREAM_FAIL;
 754                                 goto error;
 755                         }
 756                         /* Update the stream global counter */
 757                         ksess->stream_count_global += ret;
 758                 }
 759         }
 760
 761         /* Setup kernel consumer socket and send fds to it */
 762         ret = init_kernel_tracing(ksess);
 763         if (ret < 0) {
 764                 ret = LTTNG_ERR_KERN_START_FAIL;
 765                 goto error;
 766         }
 767
 768         /* This start the kernel tracing */
 769         ret = kernel_start_session(ksess);
 770         if (ret < 0) {
 771                 ret = LTTNG_ERR_KERN_START_FAIL;
 772                 goto error;
 773         }
 774
 775         /* Quiescent wait after starting trace */
 776         kernel_wait_quiescent(kernel_tracer_fd);
 777
 778         ksess->started = 1;
 779
 780         ret = LTTNG_OK;
 781
 782 error:
 783         return ret;
 784 }
 785
 786 /*
 787  * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
 788  */
 789 int cmd_disable_channel(struct ltt_session *session, int domain,
 790                 char *channel_name)
 791 {
 792         int ret;
 793         struct ltt_ust_session *usess;
 794
 795         usess = session->ust_session;
 796
 797         rcu_read_lock();
 798
 799         switch (domain) {
 800         case LTTNG_DOMAIN_KERNEL:
 801         {
 802                 ret = channel_kernel_disable(session->kernel_session,
 803                                 channel_name);
 804                 if (ret != LTTNG_OK) {
 805                         goto error;
 806                 }
 807
 808                 kernel_wait_quiescent(kernel_tracer_fd);
 809                 break;
 810         }
 811         case LTTNG_DOMAIN_UST:
 812         {
 813                 struct ltt_ust_channel *uchan;
 814                 struct lttng_ht *chan_ht;
 815
 816                 chan_ht = usess->domain_global.channels;
 817
 818                 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
 819                 if (uchan == NULL) {
 820                         ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
 821                         goto error;
 822                 }
 823
 824                 ret = channel_ust_disable(usess, uchan);
 825                 if (ret != LTTNG_OK) {
 826                         goto error;
 827                 }
 828                 break;
 829         }
 830 #if 0
 831         case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
 832         case LTTNG_DOMAIN_UST_EXEC_NAME:
 833         case LTTNG_DOMAIN_UST_PID:
 834 #endif
 835         default:
 836                 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
 837                 goto error;
 838         }
 839
 840         ret = LTTNG_OK;
 841
 842 error:
 843         rcu_read_unlock();
 844         return ret;
 845 }
 846
 847 /*
 848  * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
 849  *
 850  * The wpipe arguments is used as a notifier for the kernel thread.
 851  */
 852 int cmd_enable_channel(struct ltt_session *session,
 853                 struct lttng_domain *domain, struct lttng_channel *attr, int wpipe)
 854 {
 855         int ret;
 856         struct ltt_ust_session *usess = session->ust_session;
 857         struct lttng_ht *chan_ht;
 858
 859         assert(session);
 860         assert(attr);
 861         assert(domain);
 862
 863         DBG("Enabling channel %s for session %s", attr->name, session->name);
 864
 865         rcu_read_lock();
 866
 867         switch (domain->type) {
 868         case LTTNG_DOMAIN_KERNEL:
 869         {
 870                 struct ltt_kernel_channel *kchan;
 871
 872                 kchan = trace_kernel_get_channel_by_name(attr->name,
 873                                 session->kernel_session);
 874                 if (kchan == NULL) {
 875                         ret = channel_kernel_create(session->kernel_session, attr, wpipe);
 876                 } else {
 877                         ret = channel_kernel_enable(session->kernel_session, kchan);
 878                 }
 879
 880                 if (ret != LTTNG_OK) {
 881                         goto error;
 882                 }
 883
 884                 kernel_wait_quiescent(kernel_tracer_fd);
 885
 886                 /*
 887                  * If the session was previously started, start as well this newly
 888                  * created kernel session so the events/channels enabled *after* the
 889                  * start actually work.
 890                  */
 891                 if (session->started && !session->kernel_session->started) {
 892                         ret = start_kernel_session(session->kernel_session, wpipe);
 893                         if (ret != LTTNG_OK) {
 894                                 goto error;
 895                         }
 896                 }
 897                 break;
 898         }
 899         case LTTNG_DOMAIN_UST:
 900         {
 901                 struct ltt_ust_channel *uchan;
 902
 903                 chan_ht = usess->domain_global.channels;
 904
 905                 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
 906                 if (uchan == NULL) {
 907                         ret = channel_ust_create(usess, attr, domain->buf_type);
 908                 } else {
 909                         ret = channel_ust_enable(usess, uchan);
 910                 }
 911
 912                 /* Start the UST session if the session was already started. */
 913                 if (session->started && !usess->start_trace) {
 914                         ret = ust_app_start_trace_all(usess);
 915                         if (ret < 0) {
 916                                 ret = LTTNG_ERR_UST_START_FAIL;
 917                                 goto error;
 918                         }
 919                         ret = LTTNG_OK;
 920                         usess->start_trace = 1;
 921                 }
 922                 break;
 923         }
 924         default:
 925                 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
 926                 goto error;
 927         }
 928
 929 error:
 930         rcu_read_unlock();
 931         return ret;
 932 }
 933
 934
 935 /*
 936  * Command LTTNG_DISABLE_EVENT processed by the client thread.
 937  */
 938 int cmd_disable_event(struct ltt_session *session, int domain,
 939                 char *channel_name, char *event_name)
 940 {
 941         int ret;
 942
 943         rcu_read_lock();
 944
 945         switch (domain) {
 946         case LTTNG_DOMAIN_KERNEL:
 947         {
 948                 struct ltt_kernel_channel *kchan;
 949                 struct ltt_kernel_session *ksess;
 950
 951                 ksess = session->kernel_session;
 952
 953                 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
 954                 if (kchan == NULL) {
 955                         ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
 956                         goto error;
 957                 }
 958
 959                 ret = event_kernel_disable_tracepoint(kchan, event_name);
 960                 if (ret != LTTNG_OK) {
 961                         goto error;
 962                 }
 963
 964                 kernel_wait_quiescent(kernel_tracer_fd);
 965                 break;
 966         }
 967         case LTTNG_DOMAIN_UST:
 968         {
 969                 struct ltt_ust_channel *uchan;
 970                 struct ltt_ust_session *usess;
 971
 972                 usess = session->ust_session;
 973
 974                 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
 975                                 channel_name);
 976                 if (uchan == NULL) {
 977                         ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
 978                         goto error;
 979                 }
 980
 981                 ret = event_ust_disable_tracepoint(usess, uchan, event_name);
 982                 if (ret != LTTNG_OK) {
 983                         goto error;
 984                 }
 985
 986                 DBG3("Disable UST event %s in channel %s completed", event_name,
 987                                 channel_name);
 988                 break;
 989         }
 990 #if 0
 991         case LTTNG_DOMAIN_UST_EXEC_NAME:
 992         case LTTNG_DOMAIN_UST_PID:
 993         case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
 994 #endif
 995         default:
 996                 ret = LTTNG_ERR_UND;
 997                 goto error;
 998         }
 999
1000         ret = LTTNG_OK;
1001
1002 error:
1003         rcu_read_unlock();
1004         return ret;
1005 }
1006
1007 /*
1008  * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
1009  */
1010 int cmd_disable_event_all(struct ltt_session *session, int domain,
1011                 char *channel_name)
1012 {
1013         int ret;
1014
1015         rcu_read_lock();
1016
1017         switch (domain) {
1018         case LTTNG_DOMAIN_KERNEL:
1019         {
1020                 struct ltt_kernel_session *ksess;
1021                 struct ltt_kernel_channel *kchan;
1022
1023                 ksess = session->kernel_session;
1024
1025                 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1026                 if (kchan == NULL) {
1027                         ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1028                         goto error;
1029                 }
1030
1031                 ret = event_kernel_disable_all(kchan);
1032                 if (ret != LTTNG_OK) {
1033                         goto error;
1034                 }
1035
1036                 kernel_wait_quiescent(kernel_tracer_fd);
1037                 break;
1038         }
1039         case LTTNG_DOMAIN_UST:
1040         {
1041                 struct ltt_ust_session *usess;
1042                 struct ltt_ust_channel *uchan;
1043
1044                 usess = session->ust_session;
1045
1046                 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1047                                 channel_name);
1048                 if (uchan == NULL) {
1049                         ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1050                         goto error;
1051                 }
1052
1053                 ret = event_ust_disable_all_tracepoints(usess, uchan);
1054                 if (ret != 0) {
1055                         goto error;
1056                 }
1057
1058                 DBG3("Disable all UST events in channel %s completed", channel_name);
1059
1060                 break;
1061         }
1062 #if 0
1063         case LTTNG_DOMAIN_UST_EXEC_NAME:
1064         case LTTNG_DOMAIN_UST_PID:
1065         case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1066 #endif
1067         default:
1068                 ret = LTTNG_ERR_UND;
1069                 goto error;
1070         }
1071
1072         ret = LTTNG_OK;
1073
1074 error:
1075         rcu_read_unlock();
1076         return ret;
1077 }
1078
1079 /*
1080  * Command LTTNG_ADD_CONTEXT processed by the client thread.
1081  */
1082 int cmd_add_context(struct ltt_session *session, int domain,
1083                 char *channel_name, struct lttng_event_context *ctx, int kwpipe)
1084 {
1085         int ret;
1086
1087         switch (domain) {
1088         case LTTNG_DOMAIN_KERNEL:
1089                 assert(session->kernel_session);
1090
1091                 if (session->kernel_session->channel_count == 0) {
1092                         /* Create default channel */
1093                         ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1094                         if (ret != LTTNG_OK) {
1095                                 goto error;
1096                         }
1097                 }
1098
1099                 /* Add kernel context to kernel tracer */
1100                 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1101                 if (ret != LTTNG_OK) {
1102                         goto error;
1103                 }
1104                 break;
1105         case LTTNG_DOMAIN_UST:
1106         {
1107                 struct ltt_ust_session *usess = session->ust_session;
1108                 assert(usess);
1109
1110                 unsigned int chan_count =
1111                         lttng_ht_get_count(usess->domain_global.channels);
1112                 if (chan_count == 0) {
1113                         struct lttng_channel *attr;
1114                         /* Create default channel */
1115                         attr = channel_new_default_attr(domain);
1116                         if (attr == NULL) {
1117                                 ret = LTTNG_ERR_FATAL;
1118                                 goto error;
1119                         }
1120
1121                         ret = channel_ust_create(usess, attr, usess->buffer_type);
1122                         if (ret != LTTNG_OK) {
1123                                 free(attr);
1124                                 goto error;
1125                         }
1126                         free(attr);
1127                 }
1128
1129                 ret = context_ust_add(usess, domain, ctx, channel_name);
1130                 if (ret != LTTNG_OK) {
1131                         goto error;
1132                 }
1133                 break;
1134         }
1135 #if 0
1136         case LTTNG_DOMAIN_UST_EXEC_NAME:
1137         case LTTNG_DOMAIN_UST_PID:
1138         case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1139 #endif
1140         default:
1141                 ret = LTTNG_ERR_UND;
1142                 goto error;
1143         }
1144
1145         ret = LTTNG_OK;
1146
1147 error:
1148         return ret;
1149 }
1150
1151 /*
1152  * Command LTTNG_ENABLE_EVENT processed by the client thread.
1153  */
1154 int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
1155                 char *channel_name, struct lttng_event *event,
1156                 struct lttng_filter_bytecode *filter, int wpipe)
1157 {
1158         int ret, channel_created = 0;
1159         struct lttng_channel *attr;
1160
1161         assert(session);
1162         assert(event);
1163         assert(channel_name);
1164
1165         rcu_read_lock();
1166
1167         switch (domain->type) {
1168         case LTTNG_DOMAIN_KERNEL:
1169         {
1170                 struct ltt_kernel_channel *kchan;
1171
1172                 kchan = trace_kernel_get_channel_by_name(channel_name,
1173                                 session->kernel_session);
1174                 if (kchan == NULL) {
1175                         attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL);
1176                         if (attr == NULL) {
1177                                 ret = LTTNG_ERR_FATAL;
1178                                 goto error;
1179                         }
1180                         strncpy(attr->name, channel_name, sizeof(attr->name));
1181
1182                         ret = cmd_enable_channel(session, domain, attr, wpipe);
1183                         if (ret != LTTNG_OK) {
1184                                 free(attr);
1185                                 goto error;
1186                         }
1187                         free(attr);
1188
1189                         channel_created = 1;
1190                 }
1191
1192                 /* Get the newly created kernel channel pointer */
1193                 kchan = trace_kernel_get_channel_by_name(channel_name,
1194                                 session->kernel_session);
1195                 if (kchan == NULL) {
1196                         /* This sould not happen... */
1197                         ret = LTTNG_ERR_FATAL;
1198                         goto error;
1199                 }
1200
1201                 ret = event_kernel_enable_tracepoint(kchan, event);
1202                 if (ret != LTTNG_OK) {
1203                         if (channel_created) {
1204                                 /* Let's not leak a useless channel. */
1205                                 kernel_destroy_channel(kchan);
1206                         }
1207                         goto error;
1208                 }
1209
1210                 kernel_wait_quiescent(kernel_tracer_fd);
1211                 break;
1212         }
1213         case LTTNG_DOMAIN_UST:
1214         {
1215                 struct ltt_ust_channel *uchan;
1216                 struct ltt_ust_session *usess = session->ust_session;
1217
1218                 assert(usess);
1219
1220                 /* Get channel from global UST domain */
1221                 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1222                                 channel_name);
1223                 if (uchan == NULL) {
1224                         /* Create default channel */
1225                         attr = channel_new_default_attr(LTTNG_DOMAIN_UST);
1226                         if (attr == NULL) {
1227                                 ret = LTTNG_ERR_FATAL;
1228                                 goto error;
1229                         }
1230                         strncpy(attr->name, channel_name, sizeof(attr->name));
1231
1232                         ret = cmd_enable_channel(session, domain, attr, wpipe);
1233                         if (ret != LTTNG_OK) {
1234                                 free(attr);
1235                                 goto error;
1236                         }
1237                         free(attr);
1238
1239                         /* Get the newly created channel reference back */
1240                         uchan = trace_ust_find_channel_by_name(
1241                                         usess->domain_global.channels, channel_name);
1242                         assert(uchan);
1243                 }
1244
1245                 /* At this point, the session and channel exist on the tracer */
1246                 ret = event_ust_enable_tracepoint(usess, uchan, event, filter);
1247                 if (ret != LTTNG_OK) {
1248                         goto error;
1249                 }
1250                 break;
1251         }
1252 #if 0
1253         case LTTNG_DOMAIN_UST_EXEC_NAME:
1254         case LTTNG_DOMAIN_UST_PID:
1255         case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1256 #endif
1257         default:
1258                 ret = LTTNG_ERR_UND;
1259                 goto error;
1260         }
1261
1262         ret = LTTNG_OK;
1263
1264 error:
1265         rcu_read_unlock();
1266         return ret;
1267 }
1268
1269 /*
1270  * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
1271  */
1272 int cmd_enable_event_all(struct ltt_session *session,
1273                 struct lttng_domain *domain, char *channel_name, int event_type,
1274                 struct lttng_filter_bytecode *filter, int wpipe)
1275 {
1276         int ret;
1277         struct lttng_channel *attr;
1278
1279         assert(session);
1280         assert(channel_name);
1281
1282         rcu_read_lock();
1283
1284         switch (domain->type) {
1285         case LTTNG_DOMAIN_KERNEL:
1286         {
1287                 struct ltt_kernel_channel *kchan;
1288
1289                 assert(session->kernel_session);
1290
1291                 kchan = trace_kernel_get_channel_by_name(channel_name,
1292                                 session->kernel_session);
1293                 if (kchan == NULL) {
1294                         /* Create default channel */
1295                         attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL);
1296                         if (attr == NULL) {
1297                                 ret = LTTNG_ERR_FATAL;
1298                                 goto error;
1299                         }
1300                         strncpy(attr->name, channel_name, sizeof(attr->name));
1301
1302                         ret = cmd_enable_channel(session, domain, attr, wpipe);
1303                         if (ret != LTTNG_OK) {
1304                                 free(attr);
1305                                 goto error;
1306                         }
1307                         free(attr);
1308
1309                         /* Get the newly created kernel channel pointer */
1310                         kchan = trace_kernel_get_channel_by_name(channel_name,
1311                                         session->kernel_session);
1312                         assert(kchan);
1313                 }
1314
1315                 switch (event_type) {
1316                 case LTTNG_EVENT_SYSCALL:
1317                         ret = event_kernel_enable_all_syscalls(kchan, kernel_tracer_fd);
1318                         break;
1319                 case LTTNG_EVENT_TRACEPOINT:
1320                         /*
1321                          * This call enables all LTTNG_KERNEL_TRACEPOINTS and
1322                          * events already registered to the channel.
1323                          */
1324                         ret = event_kernel_enable_all_tracepoints(kchan, kernel_tracer_fd);
1325                         break;
1326                 case LTTNG_EVENT_ALL:
1327                         /* Enable syscalls and tracepoints */
1328                         ret = event_kernel_enable_all(kchan, kernel_tracer_fd);
1329                         break;
1330                 default:
1331                         ret = LTTNG_ERR_KERN_ENABLE_FAIL;
1332                         goto error;
1333                 }
1334
1335                 /* Manage return value */
1336                 if (ret != LTTNG_OK) {
1337                         /*
1338                          * On error, cmd_enable_channel call will take care of destroying
1339                          * the created channel if it was needed.
1340                          */
1341                         goto error;
1342                 }
1343
1344                 kernel_wait_quiescent(kernel_tracer_fd);
1345                 break;
1346         }
1347         case LTTNG_DOMAIN_UST:
1348         {
1349                 struct ltt_ust_channel *uchan;
1350                 struct ltt_ust_session *usess = session->ust_session;
1351
1352                 assert(usess);
1353
1354                 /* Get channel from global UST domain */
1355                 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1356                                 channel_name);
1357                 if (uchan == NULL) {
1358                         /* Create default channel */
1359                         attr = channel_new_default_attr(LTTNG_DOMAIN_UST);
1360                         if (attr == NULL) {
1361                                 ret = LTTNG_ERR_FATAL;
1362                                 goto error;
1363                         }
1364                         strncpy(attr->name, channel_name, sizeof(attr->name));
1365
1366                         ret = cmd_enable_channel(session, domain, attr, wpipe);
1367                         if (ret != LTTNG_OK) {
1368                                 free(attr);
1369                                 goto error;
1370                         }
1371                         free(attr);
1372
1373                         /* Get the newly created channel reference back */
1374                         uchan = trace_ust_find_channel_by_name(
1375                                         usess->domain_global.channels, channel_name);
1376                         assert(uchan);
1377                 }
1378
1379                 /* At this point, the session and channel exist on the tracer */
1380
1381                 switch (event_type) {
1382                 case LTTNG_EVENT_ALL:
1383                 case LTTNG_EVENT_TRACEPOINT:
1384                         ret = event_ust_enable_all_tracepoints(usess, uchan, filter);
1385                         if (ret != LTTNG_OK) {
1386                                 goto error;
1387                         }
1388                         break;
1389                 default:
1390                         ret = LTTNG_ERR_UST_ENABLE_FAIL;
1391                         goto error;
1392                 }
1393
1394                 /* Manage return value */
1395                 if (ret != LTTNG_OK) {
1396                         goto error;
1397                 }
1398
1399                 break;
1400         }
1401 #if 0
1402         case LTTNG_DOMAIN_UST_EXEC_NAME:
1403         case LTTNG_DOMAIN_UST_PID:
1404         case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1405 #endif
1406         default:
1407                 ret = LTTNG_ERR_UND;
1408                 goto error;
1409         }
1410
1411         ret = LTTNG_OK;
1412
1413 error:
1414         rcu_read_unlock();
1415         return ret;
1416 }
1417
1418
1419 /*
1420  * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
1421  */
1422 ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
1423 {
1424         int ret;
1425         ssize_t nb_events = 0;
1426
1427         switch (domain) {
1428         case LTTNG_DOMAIN_KERNEL:
1429                 nb_events = kernel_list_events(kernel_tracer_fd, events);
1430                 if (nb_events < 0) {
1431                         ret = LTTNG_ERR_KERN_LIST_FAIL;
1432                         goto error;
1433                 }
1434                 break;
1435         case LTTNG_DOMAIN_UST:
1436                 nb_events = ust_app_list_events(events);
1437                 if (nb_events < 0) {
1438                         ret = LTTNG_ERR_UST_LIST_FAIL;
1439                         goto error;
1440                 }
1441                 break;
1442         default:
1443                 ret = LTTNG_ERR_UND;
1444                 goto error;
1445         }
1446
1447         return nb_events;
1448
1449 error:
1450         /* Return negative value to differentiate return code */
1451         return -ret;
1452 }
1453
1454 /*
1455  * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
1456  */
1457 ssize_t cmd_list_tracepoint_fields(int domain,
1458                 struct lttng_event_field **fields)
1459 {
1460         int ret;
1461         ssize_t nb_fields = 0;
1462
1463         switch (domain) {
1464         case LTTNG_DOMAIN_UST:
1465                 nb_fields = ust_app_list_event_fields(fields);
1466                 if (nb_fields < 0) {
1467                         ret = LTTNG_ERR_UST_LIST_FAIL;
1468                         goto error;
1469                 }
1470                 break;
1471         case LTTNG_DOMAIN_KERNEL:
1472         default:        /* fall-through */
1473                 ret = LTTNG_ERR_UND;
1474                 goto error;
1475         }
1476
1477         return nb_fields;
1478
1479 error:
1480         /* Return negative value to differentiate return code */
1481         return -ret;
1482 }
1483
1484 /*
1485  * Command LTTNG_START_TRACE processed by the client thread.
1486  */
1487 int cmd_start_trace(struct ltt_session *session)
1488 {
1489         int ret;
1490         struct ltt_kernel_session *ksession;
1491         struct ltt_ust_session *usess;
1492
1493         assert(session);
1494
1495         /* Ease our life a bit ;) */
1496         ksession = session->kernel_session;
1497         usess = session->ust_session;
1498
1499         if (session->enabled) {
1500                 /* Already started. */
1501                 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1502                 goto error;
1503         }
1504
1505         session->enabled = 1;
1506
1507         /* Kernel tracing */
1508         if (ksession != NULL) {
1509                 ret = start_kernel_session(ksession, kernel_tracer_fd);
1510                 if (ret != LTTNG_OK) {
1511                         goto error;
1512                 }
1513         }
1514
1515         /* Flag session that trace should start automatically */
1516         if (usess) {
1517                 usess->start_trace = 1;
1518
1519                 ret = ust_app_start_trace_all(usess);
1520                 if (ret < 0) {
1521                         ret = LTTNG_ERR_UST_START_FAIL;
1522                         goto error;
1523                 }
1524         }
1525
1526         session->started = 1;
1527
1528         ret = LTTNG_OK;
1529
1530 error:
1531         return ret;
1532 }
1533
1534 /*
1535  * Command LTTNG_STOP_TRACE processed by the client thread.
1536  */
1537 int cmd_stop_trace(struct ltt_session *session)
1538 {
1539         int ret;
1540         struct ltt_kernel_channel *kchan;
1541         struct ltt_kernel_session *ksession;
1542         struct ltt_ust_session *usess;
1543
1544         assert(session);
1545
1546         /* Short cut */
1547         ksession = session->kernel_session;
1548         usess = session->ust_session;
1549
1550         if (!session->enabled) {
1551                 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
1552                 goto error;
1553         }
1554
1555         session->enabled = 0;
1556
1557         /* Kernel tracer */
1558         if (ksession) {
1559                 DBG("Stop kernel tracing");
1560
1561                 /* Flush metadata if exist */
1562                 if (ksession->metadata_stream_fd >= 0) {
1563                         ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
1564                         if (ret < 0) {
1565                                 ERR("Kernel metadata flush failed");
1566                         }
1567                 }
1568
1569                 /* Flush all buffers before stopping */
1570                 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
1571                         ret = kernel_flush_buffer(kchan);
1572                         if (ret < 0) {
1573                                 ERR("Kernel flush buffer error");
1574                         }
1575                 }
1576
1577                 ret = kernel_stop_session(ksession);
1578                 if (ret < 0) {
1579                         ret = LTTNG_ERR_KERN_STOP_FAIL;
1580                         goto error;
1581                 }
1582
1583                 kernel_wait_quiescent(kernel_tracer_fd);
1584
1585                 ksession->started = 0;
1586         }
1587
1588         if (usess) {
1589                 usess->start_trace = 0;
1590
1591                 ret = ust_app_stop_trace_all(usess);
1592                 if (ret < 0) {
1593                         ret = LTTNG_ERR_UST_STOP_FAIL;
1594                         goto error;
1595                 }
1596         }
1597
1598         session->started = 0;
1599
1600         ret = LTTNG_OK;
1601
1602 error:
1603         return ret;
1604 }
1605
1606 /*
1607  * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
1608  */
1609 int cmd_set_consumer_uri(int domain, struct ltt_session *session,
1610                 size_t nb_uri, struct lttng_uri *uris)
1611 {
1612         int ret, i;
1613         struct ltt_kernel_session *ksess = session->kernel_session;
1614         struct ltt_ust_session *usess = session->ust_session;
1615         struct consumer_output *consumer = NULL;
1616
1617         assert(session);
1618         assert(uris);
1619         assert(nb_uri > 0);
1620
1621         /* Can't enable consumer after session started. */
1622         if (session->enabled) {
1623                 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1624                 goto error;
1625         }
1626
1627         /*
1628          * This case switch makes sure the domain session has a temporary consumer
1629          * so the URL can be set.
1630          */
1631         switch (domain) {
1632         case 0:
1633                 /* Code flow error. A session MUST always have a consumer object */
1634                 assert(session->consumer);
1635                 /*
1636                  * The URL will be added to the tracing session consumer instead of a
1637                  * specific domain consumer.
1638                  */
1639                 consumer = session->consumer;
1640                 break;
1641         case LTTNG_DOMAIN_KERNEL:
1642                 /* Code flow error if we don't have a kernel session here. */
1643                 assert(ksess);
1644                 assert(ksess->consumer);
1645                 consumer = ksess->consumer;
1646                 break;
1647         case LTTNG_DOMAIN_UST:
1648                 /* Code flow error if we don't have a kernel session here. */
1649                 assert(usess);
1650                 assert(usess->consumer);
1651                 consumer = usess->consumer;
1652                 break;
1653         }
1654
1655         for (i = 0; i < nb_uri; i++) {
1656                 ret = add_uri_to_consumer(consumer, &uris[i], domain, session->name);
1657                 if (ret < 0) {
1658                         goto error;
1659                 }
1660         }
1661
1662         /* All good! */
1663         ret = LTTNG_OK;
1664
1665 error:
1666         return ret;
1667 }
1668
1669 /*
1670  * Command LTTNG_CREATE_SESSION processed by the client thread.
1671  */
1672 int cmd_create_session_uri(char *name, struct lttng_uri *uris,
1673                 size_t nb_uri, lttng_sock_cred *creds)
1674 {
1675         int ret;
1676         char *path = NULL;
1677         struct ltt_session *session;
1678
1679         assert(name);
1680
1681         /* No URIs is not possible. */
1682         if (uris == NULL) {
1683                 ret = LTTNG_ERR_SESSION_FAIL;
1684                 goto session_error;
1685         }
1686
1687         /*
1688          * Verify if the session already exist
1689          *
1690          * XXX: There is no need for the session lock list here since the caller
1691          * (process_client_msg) is holding it. We might want to change that so a
1692          * single command does not lock the entire session list.
1693          */
1694         session = session_find_by_name(name);
1695         if (session != NULL) {
1696                 ret = LTTNG_ERR_EXIST_SESS;
1697                 goto find_error;
1698         }
1699
1700         /* Create tracing session in the registry */
1701         ret = session_create(name, path, LTTNG_SOCK_GET_UID_CRED(creds),
1702                         LTTNG_SOCK_GET_GID_CRED(creds));
1703         if (ret != LTTNG_OK) {
1704                 goto session_error;
1705         }
1706
1707         /*
1708          * Get the newly created session pointer back
1709          *
1710          * XXX: There is no need for the session lock list here since the caller
1711          * (process_client_msg) is holding it. We might want to change that so a
1712          * single command does not lock the entire session list.
1713          */
1714         session = session_find_by_name(name);
1715         assert(session);
1716
1717         /* Create default consumer output for the session not yet created. */
1718         session->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
1719         if (session->consumer == NULL) {
1720                 ret = LTTNG_ERR_FATAL;
1721                 goto consumer_error;
1722         }
1723
1724         ret = cmd_set_consumer_uri(0, session, nb_uri, uris);
1725         if (ret != LTTNG_OK) {
1726                 goto consumer_error;
1727         }
1728
1729         session->consumer->enabled = 1;
1730
1731         return LTTNG_OK;
1732
1733 consumer_error:
1734         session_destroy(session);
1735 session_error:
1736 find_error:
1737         return ret;
1738 }
1739
1740 /*
1741  * Command LTTNG_DESTROY_SESSION processed by the client thread.
1742  */
1743 int cmd_destroy_session(struct ltt_session *session, int wpipe)
1744 {
1745         int ret;
1746         struct ltt_ust_session *usess;
1747         struct ltt_kernel_session *ksess;
1748
1749         /* Safety net */
1750         assert(session);
1751
1752         usess = session->ust_session;
1753         ksess = session->kernel_session;
1754
1755         /* Clean kernel session teardown */
1756         kernel_destroy_session(ksess);
1757
1758         /* UST session teardown */
1759         if (usess) {
1760                 /* Close any relayd session */
1761                 consumer_output_send_destroy_relayd(usess->consumer);
1762
1763                 /* Destroy every UST application related to this session. */
1764                 ret = ust_app_destroy_trace_all(usess);
1765                 if (ret) {
1766                         ERR("Error in ust_app_destroy_trace_all");
1767                 }
1768
1769                 /* Clean up the rest. */
1770                 trace_ust_destroy_session(usess);
1771         }
1772
1773         /*
1774          * Must notify the kernel thread here to update it's poll set in order to
1775          * remove the channel(s)' fd just destroyed.
1776          */
1777         ret = notify_thread_pipe(wpipe);
1778         if (ret < 0) {
1779                 PERROR("write kernel poll pipe");
1780         }
1781
1782         ret = session_destroy(session);
1783
1784         return ret;
1785 }
1786
1787 /*
1788  * Command LTTNG_CALIBRATE processed by the client thread.
1789  */
1790 int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
1791 {
1792         int ret;
1793
1794         switch (domain) {
1795         case LTTNG_DOMAIN_KERNEL:
1796         {
1797                 struct lttng_kernel_calibrate kcalibrate;
1798
1799                 kcalibrate.type = calibrate->type;
1800                 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
1801                 if (ret < 0) {
1802                         ret = LTTNG_ERR_KERN_ENABLE_FAIL;
1803                         goto error;
1804                 }
1805                 break;
1806         }
1807         case LTTNG_DOMAIN_UST:
1808         {
1809                 struct lttng_ust_calibrate ucalibrate;
1810
1811                 ucalibrate.type = calibrate->type;
1812                 ret = ust_app_calibrate_glb(&ucalibrate);
1813                 if (ret < 0) {
1814                         ret = LTTNG_ERR_UST_CALIBRATE_FAIL;
1815                         goto error;
1816                 }
1817                 break;
1818         }
1819         default:
1820                 ret = LTTNG_ERR_UND;
1821                 goto error;
1822         }
1823
1824         ret = LTTNG_OK;
1825
1826 error:
1827         return ret;
1828 }
1829
1830 /*
1831  * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
1832  */
1833 int cmd_register_consumer(struct ltt_session *session, int domain,
1834                 const char *sock_path, struct consumer_data *cdata)
1835 {
1836         int ret, sock;
1837         struct consumer_socket *socket;
1838
1839         assert(session);
1840         assert(cdata);
1841         assert(sock_path);
1842
1843         switch (domain) {
1844         case LTTNG_DOMAIN_KERNEL:
1845         {
1846                 struct ltt_kernel_session *ksess = session->kernel_session;
1847
1848                 assert(ksess);
1849
1850                 /* Can't register a consumer if there is already one */
1851                 if (ksess->consumer_fds_sent != 0) {
1852                         ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
1853                         goto error;
1854                 }
1855
1856                 sock = lttcomm_connect_unix_sock(sock_path);
1857                 if (sock < 0) {
1858                         ret = LTTNG_ERR_CONNECT_FAIL;
1859                         goto error;
1860                 }
1861
1862                 socket = consumer_allocate_socket(sock);
1863                 if (socket == NULL) {
1864                         ret = close(sock);
1865                         if (ret < 0) {
1866                                 PERROR("close register consumer");
1867                         }
1868                         ret = LTTNG_ERR_FATAL;
1869                         goto error;
1870                 }
1871
1872                 socket->lock = zmalloc(sizeof(pthread_mutex_t));
1873                 if (socket->lock == NULL) {
1874                         PERROR("zmalloc pthread mutex");
1875                         ret = LTTNG_ERR_FATAL;
1876                         goto error;
1877                 }
1878                 pthread_mutex_init(socket->lock, NULL);
1879                 socket->registered = 1;
1880
1881                 rcu_read_lock();
1882                 consumer_add_socket(socket, ksess->consumer);
1883                 rcu_read_unlock();
1884
1885                 pthread_mutex_lock(&cdata->pid_mutex);
1886                 cdata->pid = -1;
1887                 pthread_mutex_unlock(&cdata->pid_mutex);
1888
1889                 break;
1890         }
1891         default:
1892                 /* TODO: Userspace tracing */
1893                 ret = LTTNG_ERR_UND;
1894                 goto error;
1895         }
1896
1897         ret = LTTNG_OK;
1898
1899 error:
1900         return ret;
1901 }
1902
1903 /*
1904  * Command LTTNG_LIST_DOMAINS processed by the client thread.
1905  */
1906 ssize_t cmd_list_domains(struct ltt_session *session,
1907                 struct lttng_domain **domains)
1908 {
1909         int ret, index = 0;
1910         ssize_t nb_dom = 0;
1911
1912         if (session->kernel_session != NULL) {
1913                 DBG3("Listing domains found kernel domain");
1914                 nb_dom++;
1915         }
1916
1917         if (session->ust_session != NULL) {
1918                 DBG3("Listing domains found UST global domain");
1919                 nb_dom++;
1920         }
1921
1922         *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
1923         if (*domains == NULL) {
1924                 ret = LTTNG_ERR_FATAL;
1925                 goto error;
1926         }
1927
1928         if (session->kernel_session != NULL) {
1929                 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
1930                 index++;
1931         }
1932
1933         if (session->ust_session != NULL) {
1934                 (*domains)[index].type = LTTNG_DOMAIN_UST;
1935                 index++;
1936         }
1937
1938         return nb_dom;
1939
1940 error:
1941         /* Return negative value to differentiate return code */
1942         return -ret;
1943 }
1944
1945
1946 /*
1947  * Command LTTNG_LIST_CHANNELS processed by the client thread.
1948  */
1949 ssize_t cmd_list_channels(int domain, struct ltt_session *session,
1950                 struct lttng_channel **channels)
1951 {
1952         int ret;
1953         ssize_t nb_chan = 0;
1954
1955         switch (domain) {
1956         case LTTNG_DOMAIN_KERNEL:
1957                 if (session->kernel_session != NULL) {
1958                         nb_chan = session->kernel_session->channel_count;
1959                 }
1960                 DBG3("Number of kernel channels %zd", nb_chan);
1961                 if (nb_chan <= 0) {
1962                         ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1963                 }
1964                 break;
1965         case LTTNG_DOMAIN_UST:
1966                 if (session->ust_session != NULL) {
1967                         nb_chan = lttng_ht_get_count(
1968                                         session->ust_session->domain_global.channels);
1969                 }
1970                 DBG3("Number of UST global channels %zd", nb_chan);
1971                 if (nb_chan <= 0) {
1972                         ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1973                 }
1974                 break;
1975         default:
1976                 *channels = NULL;
1977                 ret = LTTNG_ERR_UND;
1978                 goto error;
1979         }
1980
1981         if (nb_chan > 0) {
1982                 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
1983                 if (*channels == NULL) {
1984                         ret = LTTNG_ERR_FATAL;
1985                         goto error;
1986                 }
1987
1988                 list_lttng_channels(domain, session, *channels);
1989         } else {
1990                 *channels = NULL;
1991                 /* Ret value was set in the domain switch case */
1992                 goto error;
1993         }
1994
1995         return nb_chan;
1996
1997 error:
1998         /* Return negative value to differentiate return code */
1999         return -ret;
2000 }
2001
2002 /*
2003  * Command LTTNG_LIST_EVENTS processed by the client thread.
2004  */
2005 ssize_t cmd_list_events(int domain, struct ltt_session *session,
2006                 char *channel_name, struct lttng_event **events)
2007 {
2008         int ret = 0;
2009         ssize_t nb_event = 0;
2010
2011         switch (domain) {
2012         case LTTNG_DOMAIN_KERNEL:
2013                 if (session->kernel_session != NULL) {
2014                         nb_event = list_lttng_kernel_events(channel_name,
2015                                         session->kernel_session, events);
2016                 }
2017                 break;
2018         case LTTNG_DOMAIN_UST:
2019         {
2020                 if (session->ust_session != NULL) {
2021                         nb_event = list_lttng_ust_global_events(channel_name,
2022                                         &session->ust_session->domain_global, events);
2023                 }
2024                 break;
2025         }
2026         default:
2027                 ret = LTTNG_ERR_UND;
2028                 goto error;
2029         }
2030
2031         return nb_event;
2032
2033 error:
2034         /* Return negative value to differentiate return code */
2035         return -ret;
2036 }
2037
2038 /*
2039  * Using the session list, filled a lttng_session array to send back to the
2040  * client for session listing.
2041  *
2042  * The session list lock MUST be acquired before calling this function. Use
2043  * session_lock_list() and session_unlock_list().
2044  */
2045 void cmd_list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2046                 gid_t gid)
2047 {
2048         int ret;
2049         unsigned int i = 0;
2050         struct ltt_session *session;
2051         struct ltt_session_list *list = session_get_list();
2052
2053         DBG("Getting all available session for UID %d GID %d",
2054                         uid, gid);
2055         /*
2056          * Iterate over session list and append data after the control struct in
2057          * the buffer.
2058          */
2059         cds_list_for_each_entry(session, &list->head, list) {
2060                 /*
2061                  * Only list the sessions the user can control.
2062                  */
2063                 if (!session_access_ok(session, uid, gid)) {
2064                         continue;
2065                 }
2066
2067                 struct ltt_kernel_session *ksess = session->kernel_session;
2068                 struct ltt_ust_session *usess = session->ust_session;
2069
2070                 if (session->consumer->type == CONSUMER_DST_NET ||
2071                                 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
2072                                 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
2073                         ret = build_network_session_path(sessions[i].path,
2074                                         sizeof(session[i].path), session);
2075                 } else {
2076                         ret = snprintf(sessions[i].path, sizeof(session[i].path), "%s",
2077                                         session->consumer->dst.trace_path);
2078                 }
2079                 if (ret < 0) {
2080                         PERROR("snprintf session path");
2081                         continue;
2082                 }
2083
2084                 strncpy(sessions[i].name, session->name, NAME_MAX);
2085                 sessions[i].name[NAME_MAX - 1] = '\0';
2086                 sessions[i].enabled = session->enabled;
2087                 i++;
2088         }
2089 }
2090
2091 /*
2092  * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
2093  * ready for trace analysis (or anykind of reader) or else 1 for pending data.
2094  */
2095 int cmd_data_pending(struct ltt_session *session)
2096 {
2097         int ret;
2098         struct ltt_kernel_session *ksess = session->kernel_session;
2099         struct ltt_ust_session *usess = session->ust_session;
2100
2101         assert(session);
2102
2103         /* Session MUST be stopped to ask for data availability. */
2104         if (session->enabled) {
2105                 ret = LTTNG_ERR_SESSION_STARTED;
2106                 goto error;
2107         }
2108
2109         if (ksess && ksess->consumer) {
2110                 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
2111                 if (ret == 1) {
2112                         /* Data is still being extracted for the kernel. */
2113                         goto error;
2114                 }
2115         }
2116
2117         if (usess && usess->consumer) {
2118                 ret = consumer_is_data_pending(usess->id, usess->consumer);
2119                 if (ret == 1) {
2120                         /* Data is still being extracted for the kernel. */
2121                         goto error;
2122                 }
2123         }
2124
2125         /* Data is ready to be read by a viewer */
2126         ret = 0;
2127
2128 error:
2129         return ret;
2130 }
2131
2132 /*
2133  * Init command subsystem.
2134  */
2135 void cmd_init(void)
2136 {
2137         /*
2138          * Set network sequence index to 1 for streams to match a relayd
2139          * socket on the consumer side.
2140          */
2141         pthread_mutex_lock(&relayd_net_seq_idx_lock);
2142         relayd_net_seq_idx = 1;
2143         pthread_mutex_unlock(&relayd_net_seq_idx_lock);
2144
2145         DBG("Command subsystem initialized");
2146 }