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 || (!kuri && !uuri)) {
 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                 if (consumer->type == CONSUMER_DST_NET) {
 384                         if ((uri->stype == LTTNG_STREAM_CONTROL &&
 385                                 consumer->dst.net.control_isset) ||
 386                                 (uri->stype == LTTNG_STREAM_DATA &&
 387                                 consumer->dst.net.data_isset)) {
 388                                 ret = LTTNG_ERR_URL_EXIST;
 389                                 goto error;
 390                         }
 391                 } else {
 392                         memset(&consumer->dst.net, 0, sizeof(consumer->dst.net));
 393                 }
 394
 395                 consumer->type = CONSUMER_DST_NET;
 396
 397                 /* Set URI into consumer output object */
 398                 ret = consumer_set_network_uri(consumer, uri);
 399                 if (ret < 0) {
 400                         ret = -ret;
 401                         goto error;
 402                 } else if (ret == 1) {
 403                         /*
 404                          * URI was the same in the consumer so we do not append the subdir
 405                          * again so to not duplicate output dir.
 406                          */
 407                         goto error;
 408                 }
 409
 410                 if (uri->stype == LTTNG_STREAM_CONTROL && strlen(uri->subdir) == 0) {
 411                         ret = consumer_set_subdir(consumer, session_name);
 412                         if (ret < 0) {
 413                                 ret = LTTNG_ERR_FATAL;
 414                                 goto error;
 415                         }
 416                 }
 417
 418                 if (uri->stype == LTTNG_STREAM_CONTROL) {
 419                         /* On a new subdir, reappend the default trace dir. */
 420                         strncat(consumer->subdir, default_trace_dir,
 421                                         sizeof(consumer->subdir) - strlen(consumer->subdir) - 1);
 422                         DBG3("Append domain trace name to subdir %s", consumer->subdir);
 423                 }
 424
 425                 break;
 426         case LTTNG_DST_PATH:
 427                 DBG2("Setting trace directory path from URI to %s", uri->dst.path);
 428                 memset(consumer->dst.trace_path, 0,
 429                                 sizeof(consumer->dst.trace_path));
 430                 strncpy(consumer->dst.trace_path, uri->dst.path,
 431                                 sizeof(consumer->dst.trace_path));
 432                 /* Append default trace dir */
 433                 strncat(consumer->dst.trace_path, default_trace_dir,
 434                                 sizeof(consumer->dst.trace_path) -
 435                                 strlen(consumer->dst.trace_path) - 1);
 436                 /* Flag consumer as local. */
 437                 consumer->type = CONSUMER_DST_LOCAL;
 438                 break;
 439         }
 440
 441         ret = LTTNG_OK;
 442
 443 error:
 444         return ret;
 445 }
 446
 447 /*
 448  * Init tracing by creating trace directory and sending fds kernel consumer.
 449  */
 450 static int init_kernel_tracing(struct ltt_kernel_session *session)
 451 {
 452         int ret = 0;
 453         struct lttng_ht_iter iter;
 454         struct consumer_socket *socket;
 455
 456         assert(session);
 457
 458         rcu_read_lock();
 459
 460         if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
 461                 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
 462                                 socket, node.node) {
 463                         /* Code flow error */
 464                         assert(socket->fd >= 0);
 465
 466                         pthread_mutex_lock(socket->lock);
 467                         ret = kernel_consumer_send_session(socket, session);
 468                         pthread_mutex_unlock(socket->lock);
 469                         if (ret < 0) {
 470                                 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
 471                                 goto error;
 472                         }
 473                 }
 474         }
 475
 476 error:
 477         rcu_read_unlock();
 478         return ret;
 479 }
 480
 481 /*
 482  * Create a socket to the relayd using the URI.
 483  *
 484  * On success, the relayd_sock pointer is set to the created socket.
 485  * Else, it's stays untouched and a lttcomm error code is returned.
 486  */
 487 static int create_connect_relayd(struct lttng_uri *uri,
 488                 struct lttcomm_relayd_sock **relayd_sock)
 489 {
 490         int ret;
 491         struct lttcomm_relayd_sock *rsock;
 492
 493         rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
 494                         RELAYD_VERSION_COMM_MINOR);
 495         if (!rsock) {
 496                 ret = LTTNG_ERR_FATAL;
 497                 goto error;
 498         }
 499
 500         /*
 501          * Connect to relayd so we can proceed with a session creation. This call
 502          * can possibly block for an arbitrary amount of time to set the health
 503          * state to be in poll execution.
 504          */
 505         health_poll_entry();
 506         ret = relayd_connect(rsock);
 507         health_poll_exit();
 508         if (ret < 0) {
 509                 ERR("Unable to reach lttng-relayd");
 510                 ret = LTTNG_ERR_RELAYD_CONNECT_FAIL;
 511                 goto free_sock;
 512         }
 513
 514         /* Create socket for control stream. */
 515         if (uri->stype == LTTNG_STREAM_CONTROL) {
 516                 DBG3("Creating relayd stream socket from URI");
 517
 518                 /* Check relayd version */
 519                 ret = relayd_version_check(rsock);
 520                 if (ret < 0) {
 521                         ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
 522                         goto close_sock;
 523                 }
 524         } else if (uri->stype == LTTNG_STREAM_DATA) {
 525                 DBG3("Creating relayd data socket from URI");
 526         } else {
 527                 /* Command is not valid */
 528                 ERR("Relayd invalid stream type: %d", uri->stype);
 529                 ret = LTTNG_ERR_INVALID;
 530                 goto close_sock;
 531         }
 532
 533         *relayd_sock = rsock;
 534
 535         return LTTNG_OK;
 536
 537 close_sock:
 538         /* The returned value is not useful since we are on an error path. */
 539         (void) relayd_close(rsock);
 540 free_sock:
 541         free(rsock);
 542 error:
 543         return ret;
 544 }
 545
 546 /*
 547  * Connect to the relayd using URI and send the socket to the right consumer.
 548  */
 549 static int send_consumer_relayd_socket(int domain, struct ltt_session *session,
 550                 struct lttng_uri *relayd_uri, struct consumer_output *consumer,
 551                 struct consumer_socket *consumer_sock)
 552 {
 553         int ret;
 554         struct lttcomm_relayd_sock *rsock = NULL;
 555
 556         /* Connect to relayd and make version check if uri is the control. */
 557         ret = create_connect_relayd(relayd_uri, &rsock);
 558         if (ret != LTTNG_OK) {
 559                 goto error;
 560         }
 561         assert(rsock);
 562
 563         /* If the control socket is connected, network session is ready */
 564         if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
 565                 session->net_handle = 1;
 566         }
 567
 568         /* Set the network sequence index if not set. */
 569         if (consumer->net_seq_index == (uint64_t) -1ULL) {
 570                 pthread_mutex_lock(&relayd_net_seq_idx_lock);
 571                 /*
 572                  * Increment net_seq_idx because we are about to transfer the
 573                  * new relayd socket to the consumer.
 574                  * Assign unique key so the consumer can match streams.
 575                  */
 576                 consumer->net_seq_index = ++relayd_net_seq_idx;
 577                 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
 578         }
 579
 580         /* Send relayd socket to consumer. */
 581         ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
 582                         relayd_uri->stype, session->id);
 583         if (ret < 0) {
 584                 ret = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
 585                 goto close_sock;
 586         }
 587
 588         /* Flag that the corresponding socket was sent. */
 589         if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
 590                 consumer_sock->control_sock_sent = 1;
 591         } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
 592                 consumer_sock->data_sock_sent = 1;
 593         }
 594
 595         ret = LTTNG_OK;
 596
 597         /*
 598          * Close socket which was dup on the consumer side. The session daemon does
 599          * NOT keep track of the relayd socket(s) once transfer to the consumer.
 600          */
 601
 602 close_sock:
 603         (void) relayd_close(rsock);
 604         free(rsock);
 605
 606 error:
 607         if (ret != LTTNG_OK) {
 608                 /*
 609                  * The consumer output for this session should not be used anymore
 610                  * since the relayd connection failed thus making any tracing or/and
 611                  * streaming not usable.
 612                  */
 613                 consumer->enabled = 0;
 614         }
 615         return ret;
 616 }
 617
 618 /*
 619  * Send both relayd sockets to a specific consumer and domain.  This is a
 620  * helper function to facilitate sending the information to the consumer for a
 621  * session.
 622  */
 623 static int send_consumer_relayd_sockets(int domain,
 624                 struct ltt_session *session, struct consumer_output *consumer,
 625                 struct consumer_socket *sock)
 626 {
 627         int ret = LTTNG_OK;
 628
 629         assert(session);
 630         assert(consumer);
 631
 632         /* Sending control relayd socket. */
 633         if (!sock->control_sock_sent) {
 634                 ret = send_consumer_relayd_socket(domain, session,
 635                                 &consumer->dst.net.control, consumer, sock);
 636                 if (ret != LTTNG_OK) {
 637                         goto error;
 638                 }
 639         }
 640
 641         /* Sending data relayd socket. */
 642         if (!sock->data_sock_sent) {
 643                 ret = send_consumer_relayd_socket(domain, session,
 644                                 &consumer->dst.net.data, consumer, sock);
 645                 if (ret != LTTNG_OK) {
 646                         goto error;
 647                 }
 648         }
 649
 650 error:
 651         return ret;
 652 }
 653
 654 /*
 655  * Setup relayd connections for a tracing session. First creates the socket to
 656  * the relayd and send them to the right domain consumer. Consumer type MUST be
 657  * network.
 658  */
 659 int cmd_setup_relayd(struct ltt_session *session)
 660 {
 661         int ret = LTTNG_OK;
 662         struct ltt_ust_session *usess;
 663         struct ltt_kernel_session *ksess;
 664         struct consumer_socket *socket;
 665         struct lttng_ht_iter iter;
 666
 667         assert(session);
 668
 669         usess = session->ust_session;
 670         ksess = session->kernel_session;
 671
 672         DBG("Setting relayd for session %s", session->name);
 673
 674         rcu_read_lock();
 675
 676         if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
 677                         && usess->consumer->enabled) {
 678                 /* For each consumer socket, send relayd sockets */
 679                 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
 680                                 socket, node.node) {
 681                         /* Code flow error */
 682                         assert(socket->fd >= 0);
 683
 684                         pthread_mutex_lock(socket->lock);
 685                         ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session,
 686                                         usess->consumer, socket);
 687                         pthread_mutex_unlock(socket->lock);
 688                         if (ret != LTTNG_OK) {
 689                                 goto error;
 690                         }
 691                 }
 692         }
 693
 694         if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
 695                         && ksess->consumer->enabled) {
 696                 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
 697                                 socket, node.node) {
 698                         /* Code flow error */
 699                         assert(socket->fd >= 0);
 700
 701                         pthread_mutex_lock(socket->lock);
 702                         ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session,
 703                                         ksess->consumer, socket);
 704                         pthread_mutex_unlock(socket->lock);
 705                         if (ret != LTTNG_OK) {
 706                                 goto error;
 707                         }
 708                 }
 709         }
 710
 711 error:
 712         rcu_read_unlock();
 713         return ret;
 714 }
 715
 716 /*
 717  * Start a kernel session by opening all necessary streams.
 718  */
 719 static int start_kernel_session(struct ltt_kernel_session *ksess, int wpipe)
 720 {
 721         int ret;
 722         struct ltt_kernel_channel *kchan;
 723
 724         /* Open kernel metadata */
 725         if (ksess->metadata == NULL) {
 726                 ret = kernel_open_metadata(ksess);
 727                 if (ret < 0) {
 728                         ret = LTTNG_ERR_KERN_META_FAIL;
 729                         goto error;
 730                 }
 731         }
 732
 733         /* Open kernel metadata stream */
 734         if (ksess->metadata_stream_fd < 0) {
 735                 ret = kernel_open_metadata_stream(ksess);
 736                 if (ret < 0) {
 737                         ERR("Kernel create metadata stream failed");
 738                         ret = LTTNG_ERR_KERN_STREAM_FAIL;
 739                         goto error;
 740                 }
 741         }
 742
 743         /* For each channel */
 744         cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
 745                 if (kchan->stream_count == 0) {
 746                         ret = kernel_open_channel_stream(kchan);
 747                         if (ret < 0) {
 748                                 ret = LTTNG_ERR_KERN_STREAM_FAIL;
 749                                 goto error;
 750                         }
 751                         /* Update the stream global counter */
 752                         ksess->stream_count_global += ret;
 753                 }
 754         }
 755
 756         /* Setup kernel consumer socket and send fds to it */
 757         ret = init_kernel_tracing(ksess);
 758         if (ret != 0) {
 759                 ret = LTTNG_ERR_KERN_START_FAIL;
 760                 goto error;
 761         }
 762
 763         /* This start the kernel tracing */
 764         ret = kernel_start_session(ksess);
 765         if (ret < 0) {
 766                 ret = LTTNG_ERR_KERN_START_FAIL;
 767                 goto error;
 768         }
 769
 770         /* Quiescent wait after starting trace */
 771         kernel_wait_quiescent(kernel_tracer_fd);
 772
 773         ksess->started = 1;
 774
 775         ret = LTTNG_OK;
 776
 777 error:
 778         return ret;
 779 }
 780
 781 /*
 782  * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
 783  */
 784 int cmd_disable_channel(struct ltt_session *session, int domain,
 785                 char *channel_name)
 786 {
 787         int ret;
 788         struct ltt_ust_session *usess;
 789
 790         usess = session->ust_session;
 791
 792         rcu_read_lock();
 793
 794         switch (domain) {
 795         case LTTNG_DOMAIN_KERNEL:
 796         {
 797                 ret = channel_kernel_disable(session->kernel_session,
 798                                 channel_name);
 799                 if (ret != LTTNG_OK) {
 800                         goto error;
 801                 }
 802
 803                 kernel_wait_quiescent(kernel_tracer_fd);
 804                 break;
 805         }
 806         case LTTNG_DOMAIN_UST:
 807         {
 808                 struct ltt_ust_channel *uchan;
 809                 struct lttng_ht *chan_ht;
 810
 811                 chan_ht = usess->domain_global.channels;
 812
 813                 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
 814                 if (uchan == NULL) {
 815                         ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
 816                         goto error;
 817                 }
 818
 819                 ret = channel_ust_disable(usess, uchan);
 820                 if (ret != LTTNG_OK) {
 821                         goto error;
 822                 }
 823                 break;
 824         }
 825 #if 0
 826         case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
 827         case LTTNG_DOMAIN_UST_EXEC_NAME:
 828         case LTTNG_DOMAIN_UST_PID:
 829 #endif
 830         default:
 831                 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
 832                 goto error;
 833         }
 834
 835         ret = LTTNG_OK;
 836
 837 error:
 838         rcu_read_unlock();
 839         return ret;
 840 }
 841
 842 /*
 843  * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
 844  *
 845  * The wpipe arguments is used as a notifier for the kernel thread.
 846  */
 847 int cmd_enable_channel(struct ltt_session *session,
 848                 struct lttng_domain *domain, struct lttng_channel *attr, int wpipe)
 849 {
 850         int ret;
 851         struct ltt_ust_session *usess = session->ust_session;
 852         struct lttng_ht *chan_ht;
 853
 854         assert(session);
 855         assert(attr);
 856         assert(domain);
 857
 858         DBG("Enabling channel %s for session %s", attr->name, session->name);
 859
 860         /*
 861          * Don't try to enable a channel if the session has been started at
 862          * some point in time before. The tracer does not allow it.
 863          */
 864         if (session->started) {
 865                 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
 866                 goto error;
 867         }
 868
 869         rcu_read_lock();
 870
 871         switch (domain->type) {
 872         case LTTNG_DOMAIN_KERNEL:
 873         {
 874                 struct ltt_kernel_channel *kchan;
 875
 876                 kchan = trace_kernel_get_channel_by_name(attr->name,
 877                                 session->kernel_session);
 878                 if (kchan == NULL) {
 879                         ret = channel_kernel_create(session->kernel_session, attr, wpipe);
 880                 } else {
 881                         ret = channel_kernel_enable(session->kernel_session, kchan);
 882                 }
 883
 884                 if (ret != LTTNG_OK) {
 885                         goto error;
 886                 }
 887
 888                 kernel_wait_quiescent(kernel_tracer_fd);
 889                 break;
 890         }
 891         case LTTNG_DOMAIN_UST:
 892         {
 893                 struct ltt_ust_channel *uchan;
 894
 895                 chan_ht = usess->domain_global.channels;
 896
 897                 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
 898                 if (uchan == NULL) {
 899                         ret = channel_ust_create(usess, attr, domain->buf_type);
 900                 } else {
 901                         ret = channel_ust_enable(usess, uchan);
 902                 }
 903                 break;
 904         }
 905         default:
 906                 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
 907                 goto error;
 908         }
 909
 910 error:
 911         rcu_read_unlock();
 912         return ret;
 913 }
 914
 915
 916 /*
 917  * Command LTTNG_DISABLE_EVENT processed by the client thread.
 918  */
 919 int cmd_disable_event(struct ltt_session *session, int domain,
 920                 char *channel_name, char *event_name)
 921 {
 922         int ret;
 923
 924         rcu_read_lock();
 925
 926         switch (domain) {
 927         case LTTNG_DOMAIN_KERNEL:
 928         {
 929                 struct ltt_kernel_channel *kchan;
 930                 struct ltt_kernel_session *ksess;
 931
 932                 ksess = session->kernel_session;
 933
 934                 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
 935                 if (kchan == NULL) {
 936                         ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
 937                         goto error;
 938                 }
 939
 940                 ret = event_kernel_disable_tracepoint(kchan, event_name);
 941                 if (ret != LTTNG_OK) {
 942                         goto error;
 943                 }
 944
 945                 kernel_wait_quiescent(kernel_tracer_fd);
 946                 break;
 947         }
 948         case LTTNG_DOMAIN_UST:
 949         {
 950                 struct ltt_ust_channel *uchan;
 951                 struct ltt_ust_session *usess;
 952
 953                 usess = session->ust_session;
 954
 955                 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
 956                                 channel_name);
 957                 if (uchan == NULL) {
 958                         ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
 959                         goto error;
 960                 }
 961
 962                 ret = event_ust_disable_tracepoint(usess, uchan, event_name);
 963                 if (ret != LTTNG_OK) {
 964                         goto error;
 965                 }
 966
 967                 DBG3("Disable UST event %s in channel %s completed", event_name,
 968                                 channel_name);
 969                 break;
 970         }
 971 #if 0
 972         case LTTNG_DOMAIN_UST_EXEC_NAME:
 973         case LTTNG_DOMAIN_UST_PID:
 974         case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
 975 #endif
 976         default:
 977                 ret = LTTNG_ERR_UND;
 978                 goto error;
 979         }
 980
 981         ret = LTTNG_OK;
 982
 983 error:
 984         rcu_read_unlock();
 985         return ret;
 986 }
 987
 988 /*
 989  * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
 990  */
 991 int cmd_disable_event_all(struct ltt_session *session, int domain,
 992                 char *channel_name)
 993 {
 994         int ret;
 995
 996         rcu_read_lock();
 997
 998         switch (domain) {
 999         case LTTNG_DOMAIN_KERNEL:
1000         {
1001                 struct ltt_kernel_session *ksess;
1002                 struct ltt_kernel_channel *kchan;
1003
1004                 ksess = session->kernel_session;
1005
1006                 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1007                 if (kchan == NULL) {
1008                         ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1009                         goto error;
1010                 }
1011
1012                 ret = event_kernel_disable_all(kchan);
1013                 if (ret != LTTNG_OK) {
1014                         goto error;
1015                 }
1016
1017                 kernel_wait_quiescent(kernel_tracer_fd);
1018                 break;
1019         }
1020         case LTTNG_DOMAIN_UST:
1021         {
1022                 struct ltt_ust_session *usess;
1023                 struct ltt_ust_channel *uchan;
1024
1025                 usess = session->ust_session;
1026
1027                 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1028                                 channel_name);
1029                 if (uchan == NULL) {
1030                         ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1031                         goto error;
1032                 }
1033
1034                 ret = event_ust_disable_all_tracepoints(usess, uchan);
1035                 if (ret != 0) {
1036                         goto error;
1037                 }
1038
1039                 DBG3("Disable all UST events in channel %s completed", channel_name);
1040
1041                 break;
1042         }
1043 #if 0
1044         case LTTNG_DOMAIN_UST_EXEC_NAME:
1045         case LTTNG_DOMAIN_UST_PID:
1046         case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1047 #endif
1048         default:
1049                 ret = LTTNG_ERR_UND;
1050                 goto error;
1051         }
1052
1053         ret = LTTNG_OK;
1054
1055 error:
1056         rcu_read_unlock();
1057         return ret;
1058 }
1059
1060 /*
1061  * Command LTTNG_ADD_CONTEXT processed by the client thread.
1062  */
1063 int cmd_add_context(struct ltt_session *session, int domain,
1064                 char *channel_name, struct lttng_event_context *ctx, int kwpipe)
1065 {
1066         int ret, chan_kern_created = 0, chan_ust_created = 0;
1067
1068         switch (domain) {
1069         case LTTNG_DOMAIN_KERNEL:
1070                 assert(session->kernel_session);
1071
1072                 if (session->kernel_session->channel_count == 0) {
1073                         /* Create default channel */
1074                         ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1075                         if (ret != LTTNG_OK) {
1076                                 goto error;
1077                         }
1078                         chan_kern_created = 1;
1079                 }
1080
1081                 /* Add kernel context to kernel tracer */
1082                 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1083                 if (ret != LTTNG_OK) {
1084                         goto error;
1085                 }
1086                 break;
1087         case LTTNG_DOMAIN_UST:
1088         {
1089                 struct ltt_ust_session *usess = session->ust_session;
1090                 assert(usess);
1091
1092                 unsigned int chan_count =
1093                         lttng_ht_get_count(usess->domain_global.channels);
1094                 if (chan_count == 0) {
1095                         struct lttng_channel *attr;
1096                         /* Create default channel */
1097                         attr = channel_new_default_attr(domain, usess->buffer_type);
1098                         if (attr == NULL) {
1099                                 ret = LTTNG_ERR_FATAL;
1100                                 goto error;
1101                         }
1102
1103                         ret = channel_ust_create(usess, attr, usess->buffer_type);
1104                         if (ret != LTTNG_OK) {
1105                                 free(attr);
1106                                 goto error;
1107                         }
1108                         free(attr);
1109                         chan_ust_created = 1;
1110                 }
1111
1112                 ret = context_ust_add(usess, domain, ctx, channel_name);
1113                 if (ret != LTTNG_OK) {
1114                         goto error;
1115                 }
1116                 break;
1117         }
1118 #if 0
1119         case LTTNG_DOMAIN_UST_EXEC_NAME:
1120         case LTTNG_DOMAIN_UST_PID:
1121         case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1122 #endif
1123         default:
1124                 ret = LTTNG_ERR_UND;
1125                 goto error;
1126         }
1127
1128         return LTTNG_OK;
1129
1130 error:
1131         if (chan_kern_created) {
1132                 struct ltt_kernel_channel *kchan =
1133                         trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
1134                                         session->kernel_session);
1135                 /* Created previously, this should NOT fail. */
1136                 assert(kchan);
1137                 kernel_destroy_channel(kchan);
1138         }
1139
1140         if (chan_ust_created) {
1141                 struct ltt_ust_channel *uchan =
1142                         trace_ust_find_channel_by_name(
1143                                         session->ust_session->domain_global.channels,
1144                                         DEFAULT_CHANNEL_NAME);
1145                 /* Created previously, this should NOT fail. */
1146                 assert(uchan);
1147                 /* Remove from the channel list of the session. */
1148                 trace_ust_delete_channel(session->ust_session->domain_global.channels,
1149                                 uchan);
1150                 trace_ust_destroy_channel(uchan);
1151         }
1152         return ret;
1153 }
1154
1155 /*
1156  * Command LTTNG_ENABLE_EVENT processed by the client thread.
1157  */
1158 int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
1159                 char *channel_name, struct lttng_event *event,
1160                 struct lttng_filter_bytecode *filter, int wpipe)
1161 {
1162         int ret, channel_created = 0;
1163         struct lttng_channel *attr;
1164
1165         assert(session);
1166         assert(event);
1167         assert(channel_name);
1168
1169         rcu_read_lock();
1170
1171         switch (domain->type) {
1172         case LTTNG_DOMAIN_KERNEL:
1173         {
1174                 struct ltt_kernel_channel *kchan;
1175
1176                 kchan = trace_kernel_get_channel_by_name(channel_name,
1177                                 session->kernel_session);
1178                 if (kchan == NULL) {
1179                         attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
1180                                         LTTNG_BUFFER_GLOBAL);
1181                         if (attr == NULL) {
1182                                 ret = LTTNG_ERR_FATAL;
1183                                 goto error;
1184                         }
1185                         strncpy(attr->name, channel_name, sizeof(attr->name));
1186
1187                         ret = cmd_enable_channel(session, domain, attr, wpipe);
1188                         if (ret != LTTNG_OK) {
1189                                 free(attr);
1190                                 goto error;
1191                         }
1192                         free(attr);
1193
1194                         channel_created = 1;
1195                 }
1196
1197                 /* Get the newly created kernel channel pointer */
1198                 kchan = trace_kernel_get_channel_by_name(channel_name,
1199                                 session->kernel_session);
1200                 if (kchan == NULL) {
1201                         /* This sould not happen... */
1202                         ret = LTTNG_ERR_FATAL;
1203                         goto error;
1204                 }
1205
1206                 ret = event_kernel_enable_tracepoint(kchan, event);
1207                 if (ret != LTTNG_OK) {
1208                         if (channel_created) {
1209                                 /* Let's not leak a useless channel. */
1210                                 kernel_destroy_channel(kchan);
1211                         }
1212                         goto error;
1213                 }
1214
1215                 kernel_wait_quiescent(kernel_tracer_fd);
1216                 break;
1217         }
1218         case LTTNG_DOMAIN_UST:
1219         {
1220                 struct ltt_ust_channel *uchan;
1221                 struct ltt_ust_session *usess = session->ust_session;
1222
1223                 assert(usess);
1224
1225                 /* Get channel from global UST domain */
1226                 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1227                                 channel_name);
1228                 if (uchan == NULL) {
1229                         /* Create default channel */
1230                         attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
1231                                         usess->buffer_type);
1232                         if (attr == NULL) {
1233                                 ret = LTTNG_ERR_FATAL;
1234                                 goto error;
1235                         }
1236                         strncpy(attr->name, channel_name, sizeof(attr->name));
1237
1238                         ret = cmd_enable_channel(session, domain, attr, wpipe);
1239                         if (ret != LTTNG_OK) {
1240                                 free(attr);
1241                                 goto error;
1242                         }
1243                         free(attr);
1244
1245                         /* Get the newly created channel reference back */
1246                         uchan = trace_ust_find_channel_by_name(
1247                                         usess->domain_global.channels, channel_name);
1248                         assert(uchan);
1249                 }
1250
1251                 /* At this point, the session and channel exist on the tracer */
1252                 ret = event_ust_enable_tracepoint(usess, uchan, event, filter);
1253                 if (ret != LTTNG_OK) {
1254                         goto error;
1255                 }
1256                 break;
1257         }
1258 #if 0
1259         case LTTNG_DOMAIN_UST_EXEC_NAME:
1260         case LTTNG_DOMAIN_UST_PID:
1261         case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1262 #endif
1263         default:
1264                 ret = LTTNG_ERR_UND;
1265                 goto error;
1266         }
1267
1268         ret = LTTNG_OK;
1269
1270 error:
1271         rcu_read_unlock();
1272         return ret;
1273 }
1274
1275 /*
1276  * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
1277  */
1278 int cmd_enable_event_all(struct ltt_session *session,
1279                 struct lttng_domain *domain, char *channel_name, int event_type,
1280                 struct lttng_filter_bytecode *filter, int wpipe)
1281 {
1282         int ret;
1283         struct lttng_channel *attr;
1284
1285         assert(session);
1286         assert(channel_name);
1287
1288         rcu_read_lock();
1289
1290         switch (domain->type) {
1291         case LTTNG_DOMAIN_KERNEL:
1292         {
1293                 struct ltt_kernel_channel *kchan;
1294
1295                 assert(session->kernel_session);
1296
1297                 kchan = trace_kernel_get_channel_by_name(channel_name,
1298                                 session->kernel_session);
1299                 if (kchan == NULL) {
1300                         /* Create default channel */
1301                         attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
1302                                         LTTNG_BUFFER_GLOBAL);
1303                         if (attr == NULL) {
1304                                 ret = LTTNG_ERR_FATAL;
1305                                 goto error;
1306                         }
1307                         strncpy(attr->name, channel_name, sizeof(attr->name));
1308
1309                         ret = cmd_enable_channel(session, domain, attr, wpipe);
1310                         if (ret != LTTNG_OK) {
1311                                 free(attr);
1312                                 goto error;
1313                         }
1314                         free(attr);
1315
1316                         /* Get the newly created kernel channel pointer */
1317                         kchan = trace_kernel_get_channel_by_name(channel_name,
1318                                         session->kernel_session);
1319                         assert(kchan);
1320                 }
1321
1322                 switch (event_type) {
1323                 case LTTNG_EVENT_SYSCALL:
1324                         ret = event_kernel_enable_all_syscalls(kchan, kernel_tracer_fd);
1325                         break;
1326                 case LTTNG_EVENT_TRACEPOINT:
1327                         /*
1328                          * This call enables all LTTNG_KERNEL_TRACEPOINTS and
1329                          * events already registered to the channel.
1330                          */
1331                         ret = event_kernel_enable_all_tracepoints(kchan, kernel_tracer_fd);
1332                         break;
1333                 case LTTNG_EVENT_ALL:
1334                         /* Enable syscalls and tracepoints */
1335                         ret = event_kernel_enable_all(kchan, kernel_tracer_fd);
1336                         break;
1337                 default:
1338                         ret = LTTNG_ERR_KERN_ENABLE_FAIL;
1339                         goto error;
1340                 }
1341
1342                 /* Manage return value */
1343                 if (ret != LTTNG_OK) {
1344                         /*
1345                          * On error, cmd_enable_channel call will take care of destroying
1346                          * the created channel if it was needed.
1347                          */
1348                         goto error;
1349                 }
1350
1351                 kernel_wait_quiescent(kernel_tracer_fd);
1352                 break;
1353         }
1354         case LTTNG_DOMAIN_UST:
1355         {
1356                 struct ltt_ust_channel *uchan;
1357                 struct ltt_ust_session *usess = session->ust_session;
1358
1359                 assert(usess);
1360
1361                 /* Get channel from global UST domain */
1362                 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1363                                 channel_name);
1364                 if (uchan == NULL) {
1365                         /* Create default channel */
1366                         attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
1367                                         usess->buffer_type);
1368                         if (attr == NULL) {
1369                                 ret = LTTNG_ERR_FATAL;
1370                                 goto error;
1371                         }
1372                         strncpy(attr->name, channel_name, sizeof(attr->name));
1373
1374                         ret = cmd_enable_channel(session, domain, attr, wpipe);
1375                         if (ret != LTTNG_OK) {
1376                                 free(attr);
1377                                 goto error;
1378                         }
1379                         free(attr);
1380
1381                         /* Get the newly created channel reference back */
1382                         uchan = trace_ust_find_channel_by_name(
1383                                         usess->domain_global.channels, channel_name);
1384                         assert(uchan);
1385                 }
1386
1387                 /* At this point, the session and channel exist on the tracer */
1388
1389                 switch (event_type) {
1390                 case LTTNG_EVENT_ALL:
1391                 case LTTNG_EVENT_TRACEPOINT:
1392                         ret = event_ust_enable_all_tracepoints(usess, uchan, filter);
1393                         if (ret != LTTNG_OK) {
1394                                 goto error;
1395                         }
1396                         break;
1397                 default:
1398                         ret = LTTNG_ERR_UST_ENABLE_FAIL;
1399                         goto error;
1400                 }
1401
1402                 /* Manage return value */
1403                 if (ret != LTTNG_OK) {
1404                         goto error;
1405                 }
1406
1407                 break;
1408         }
1409 #if 0
1410         case LTTNG_DOMAIN_UST_EXEC_NAME:
1411         case LTTNG_DOMAIN_UST_PID:
1412         case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1413 #endif
1414         default:
1415                 ret = LTTNG_ERR_UND;
1416                 goto error;
1417         }
1418
1419         ret = LTTNG_OK;
1420
1421 error:
1422         rcu_read_unlock();
1423         return ret;
1424 }
1425
1426
1427 /*
1428  * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
1429  */
1430 ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
1431 {
1432         int ret;
1433         ssize_t nb_events = 0;
1434
1435         switch (domain) {
1436         case LTTNG_DOMAIN_KERNEL:
1437                 nb_events = kernel_list_events(kernel_tracer_fd, events);
1438                 if (nb_events < 0) {
1439                         ret = LTTNG_ERR_KERN_LIST_FAIL;
1440                         goto error;
1441                 }
1442                 break;
1443         case LTTNG_DOMAIN_UST:
1444                 nb_events = ust_app_list_events(events);
1445                 if (nb_events < 0) {
1446                         ret = LTTNG_ERR_UST_LIST_FAIL;
1447                         goto error;
1448                 }
1449                 break;
1450         default:
1451                 ret = LTTNG_ERR_UND;
1452                 goto error;
1453         }
1454
1455         return nb_events;
1456
1457 error:
1458         /* Return negative value to differentiate return code */
1459         return -ret;
1460 }
1461
1462 /*
1463  * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
1464  */
1465 ssize_t cmd_list_tracepoint_fields(int domain,
1466                 struct lttng_event_field **fields)
1467 {
1468         int ret;
1469         ssize_t nb_fields = 0;
1470
1471         switch (domain) {
1472         case LTTNG_DOMAIN_UST:
1473                 nb_fields = ust_app_list_event_fields(fields);
1474                 if (nb_fields < 0) {
1475                         ret = LTTNG_ERR_UST_LIST_FAIL;
1476                         goto error;
1477                 }
1478                 break;
1479         case LTTNG_DOMAIN_KERNEL:
1480         default:        /* fall-through */
1481                 ret = LTTNG_ERR_UND;
1482                 goto error;
1483         }
1484
1485         return nb_fields;
1486
1487 error:
1488         /* Return negative value to differentiate return code */
1489         return -ret;
1490 }
1491
1492 /*
1493  * Command LTTNG_START_TRACE processed by the client thread.
1494  */
1495 int cmd_start_trace(struct ltt_session *session)
1496 {
1497         int ret;
1498         struct ltt_kernel_session *ksession;
1499         struct ltt_ust_session *usess;
1500
1501         assert(session);
1502
1503         /* Ease our life a bit ;) */
1504         ksession = session->kernel_session;
1505         usess = session->ust_session;
1506
1507         if (session->enabled) {
1508                 /* Already started. */
1509                 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1510                 goto error;
1511         }
1512
1513         session->enabled = 1;
1514
1515         /* Kernel tracing */
1516         if (ksession != NULL) {
1517                 ret = start_kernel_session(ksession, kernel_tracer_fd);
1518                 if (ret != LTTNG_OK) {
1519                         goto error;
1520                 }
1521         }
1522
1523         /* Flag session that trace should start automatically */
1524         if (usess) {
1525                 usess->start_trace = 1;
1526
1527                 ret = ust_app_start_trace_all(usess);
1528                 if (ret < 0) {
1529                         ret = LTTNG_ERR_UST_START_FAIL;
1530                         goto error;
1531                 }
1532         }
1533
1534         session->started = 1;
1535
1536         ret = LTTNG_OK;
1537
1538 error:
1539         return ret;
1540 }
1541
1542 /*
1543  * Command LTTNG_STOP_TRACE processed by the client thread.
1544  */
1545 int cmd_stop_trace(struct ltt_session *session)
1546 {
1547         int ret;
1548         struct ltt_kernel_channel *kchan;
1549         struct ltt_kernel_session *ksession;
1550         struct ltt_ust_session *usess;
1551
1552         assert(session);
1553
1554         /* Short cut */
1555         ksession = session->kernel_session;
1556         usess = session->ust_session;
1557
1558         if (!session->enabled) {
1559                 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
1560                 goto error;
1561         }
1562
1563         session->enabled = 0;
1564
1565         /* Kernel tracer */
1566         if (ksession && ksession->started) {
1567                 DBG("Stop kernel tracing");
1568
1569                 /* Flush metadata if exist */
1570                 if (ksession->metadata_stream_fd >= 0) {
1571                         ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
1572                         if (ret < 0) {
1573                                 ERR("Kernel metadata flush failed");
1574                         }
1575                 }
1576
1577                 /* Flush all buffers before stopping */
1578                 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
1579                         ret = kernel_flush_buffer(kchan);
1580                         if (ret < 0) {
1581                                 ERR("Kernel flush buffer error");
1582                         }
1583                 }
1584
1585                 ret = kernel_stop_session(ksession);
1586                 if (ret < 0) {
1587                         ret = LTTNG_ERR_KERN_STOP_FAIL;
1588                         goto error;
1589                 }
1590
1591                 kernel_wait_quiescent(kernel_tracer_fd);
1592
1593                 ksession->started = 0;
1594         }
1595
1596         if (usess && usess->start_trace) {
1597                 usess->start_trace = 0;
1598
1599                 ret = ust_app_stop_trace_all(usess);
1600                 if (ret < 0) {
1601                         ret = LTTNG_ERR_UST_STOP_FAIL;
1602                         goto error;
1603                 }
1604         }
1605
1606         ret = LTTNG_OK;
1607
1608 error:
1609         return ret;
1610 }
1611
1612 /*
1613  * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
1614  */
1615 int cmd_set_consumer_uri(int domain, struct ltt_session *session,
1616                 size_t nb_uri, struct lttng_uri *uris)
1617 {
1618         int ret, i;
1619         struct ltt_kernel_session *ksess = session->kernel_session;
1620         struct ltt_ust_session *usess = session->ust_session;
1621         struct consumer_output *consumer = NULL;
1622
1623         assert(session);
1624         assert(uris);
1625         assert(nb_uri > 0);
1626
1627         /* Can't enable consumer after session started. */
1628         if (session->enabled) {
1629                 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1630                 goto error;
1631         }
1632
1633         /*
1634          * This case switch makes sure the domain session has a temporary consumer
1635          * so the URL can be set.
1636          */
1637         switch (domain) {
1638         case 0:
1639                 /* Code flow error. A session MUST always have a consumer object */
1640                 assert(session->consumer);
1641                 /*
1642                  * The URL will be added to the tracing session consumer instead of a
1643                  * specific domain consumer.
1644                  */
1645                 consumer = session->consumer;
1646                 break;
1647         case LTTNG_DOMAIN_KERNEL:
1648                 /* Code flow error if we don't have a kernel session here. */
1649                 assert(ksess);
1650                 assert(ksess->consumer);
1651                 consumer = ksess->consumer;
1652                 break;
1653         case LTTNG_DOMAIN_UST:
1654                 /* Code flow error if we don't have a kernel session here. */
1655                 assert(usess);
1656                 assert(usess->consumer);
1657                 consumer = usess->consumer;
1658                 break;
1659         }
1660
1661         for (i = 0; i < nb_uri; i++) {
1662                 ret = add_uri_to_consumer(consumer, &uris[i], domain, session->name);
1663                 if (ret != LTTNG_OK) {
1664                         goto error;
1665                 }
1666         }
1667
1668         /* All good! */
1669         ret = LTTNG_OK;
1670
1671 error:
1672         return ret;
1673 }
1674
1675 /*
1676  * Command LTTNG_CREATE_SESSION processed by the client thread.
1677  */
1678 int cmd_create_session_uri(char *name, struct lttng_uri *uris,
1679                 size_t nb_uri, lttng_sock_cred *creds)
1680 {
1681         int ret;
1682         struct ltt_session *session;
1683
1684         assert(name);
1685
1686         /* No URIs is not possible. */
1687         if (uris == NULL) {
1688                 ret = LTTNG_ERR_SESSION_FAIL;
1689                 goto session_error;
1690         }
1691
1692         /*
1693          * Verify if the session already exist
1694          *
1695          * XXX: There is no need for the session lock list here since the caller
1696          * (process_client_msg) is holding it. We might want to change that so a
1697          * single command does not lock the entire session list.
1698          */
1699         session = session_find_by_name(name);
1700         if (session != NULL) {
1701                 ret = LTTNG_ERR_EXIST_SESS;
1702                 goto find_error;
1703         }
1704
1705         /* Create tracing session in the registry */
1706         ret = session_create(name, LTTNG_SOCK_GET_UID_CRED(creds),
1707                         LTTNG_SOCK_GET_GID_CRED(creds));
1708         if (ret != LTTNG_OK) {
1709                 goto session_error;
1710         }
1711
1712         /*
1713          * Get the newly created session pointer back
1714          *
1715          * XXX: There is no need for the session lock list here since the caller
1716          * (process_client_msg) is holding it. We might want to change that so a
1717          * single command does not lock the entire session list.
1718          */
1719         session = session_find_by_name(name);
1720         assert(session);
1721
1722         /* Create default consumer output for the session not yet created. */
1723         session->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
1724         if (session->consumer == NULL) {
1725                 ret = LTTNG_ERR_FATAL;
1726                 goto consumer_error;
1727         }
1728
1729         ret = cmd_set_consumer_uri(0, session, nb_uri, uris);
1730         if (ret != LTTNG_OK) {
1731                 goto consumer_error;
1732         }
1733
1734         session->consumer->enabled = 1;
1735
1736         return LTTNG_OK;
1737
1738 consumer_error:
1739         session_destroy(session);
1740 session_error:
1741 find_error:
1742         return ret;
1743 }
1744
1745 /*
1746  * Command LTTNG_DESTROY_SESSION processed by the client thread.
1747  */
1748 int cmd_destroy_session(struct ltt_session *session, int wpipe)
1749 {
1750         int ret;
1751         struct ltt_ust_session *usess;
1752         struct ltt_kernel_session *ksess;
1753
1754         /* Safety net */
1755         assert(session);
1756
1757         usess = session->ust_session;
1758         ksess = session->kernel_session;
1759
1760         /* Clean kernel session teardown */
1761         kernel_destroy_session(ksess);
1762
1763         /* UST session teardown */
1764         if (usess) {
1765                 /* Close any relayd session */
1766                 consumer_output_send_destroy_relayd(usess->consumer);
1767
1768                 /* Destroy every UST application related to this session. */
1769                 ret = ust_app_destroy_trace_all(usess);
1770                 if (ret) {
1771                         ERR("Error in ust_app_destroy_trace_all");
1772                 }
1773
1774                 /* Clean up the rest. */
1775                 trace_ust_destroy_session(usess);
1776         }
1777
1778         /*
1779          * Must notify the kernel thread here to update it's poll set in order to
1780          * remove the channel(s)' fd just destroyed.
1781          */
1782         ret = notify_thread_pipe(wpipe);
1783         if (ret < 0) {
1784                 PERROR("write kernel poll pipe");
1785         }
1786
1787         ret = session_destroy(session);
1788
1789         return ret;
1790 }
1791
1792 /*
1793  * Command LTTNG_CALIBRATE processed by the client thread.
1794  */
1795 int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
1796 {
1797         int ret;
1798
1799         switch (domain) {
1800         case LTTNG_DOMAIN_KERNEL:
1801         {
1802                 struct lttng_kernel_calibrate kcalibrate;
1803
1804                 kcalibrate.type = calibrate->type;
1805                 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
1806                 if (ret < 0) {
1807                         ret = LTTNG_ERR_KERN_ENABLE_FAIL;
1808                         goto error;
1809                 }
1810                 break;
1811         }
1812         case LTTNG_DOMAIN_UST:
1813         {
1814                 struct lttng_ust_calibrate ucalibrate;
1815
1816                 ucalibrate.type = calibrate->type;
1817                 ret = ust_app_calibrate_glb(&ucalibrate);
1818                 if (ret < 0) {
1819                         ret = LTTNG_ERR_UST_CALIBRATE_FAIL;
1820                         goto error;
1821                 }
1822                 break;
1823         }
1824         default:
1825                 ret = LTTNG_ERR_UND;
1826                 goto error;
1827         }
1828
1829         ret = LTTNG_OK;
1830
1831 error:
1832         return ret;
1833 }
1834
1835 /*
1836  * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
1837  */
1838 int cmd_register_consumer(struct ltt_session *session, int domain,
1839                 const char *sock_path, struct consumer_data *cdata)
1840 {
1841         int ret, sock;
1842         struct consumer_socket *socket = NULL;
1843
1844         assert(session);
1845         assert(cdata);
1846         assert(sock_path);
1847
1848         switch (domain) {
1849         case LTTNG_DOMAIN_KERNEL:
1850         {
1851                 struct ltt_kernel_session *ksess = session->kernel_session;
1852
1853                 assert(ksess);
1854
1855                 /* Can't register a consumer if there is already one */
1856                 if (ksess->consumer_fds_sent != 0) {
1857                         ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
1858                         goto error;
1859                 }
1860
1861                 sock = lttcomm_connect_unix_sock(sock_path);
1862                 if (sock < 0) {
1863                         ret = LTTNG_ERR_CONNECT_FAIL;
1864                         goto error;
1865                 }
1866
1867                 socket = consumer_allocate_socket(sock);
1868                 if (socket == NULL) {
1869                         ret = close(sock);
1870                         if (ret < 0) {
1871                                 PERROR("close register consumer");
1872                         }
1873                         ret = LTTNG_ERR_FATAL;
1874                         goto error;
1875                 }
1876
1877                 socket->lock = zmalloc(sizeof(pthread_mutex_t));
1878                 if (socket->lock == NULL) {
1879                         PERROR("zmalloc pthread mutex");
1880                         ret = LTTNG_ERR_FATAL;
1881                         goto error;
1882                 }
1883                 pthread_mutex_init(socket->lock, NULL);
1884                 socket->registered = 1;
1885
1886                 rcu_read_lock();
1887                 consumer_add_socket(socket, ksess->consumer);
1888                 rcu_read_unlock();
1889
1890                 pthread_mutex_lock(&cdata->pid_mutex);
1891                 cdata->pid = -1;
1892                 pthread_mutex_unlock(&cdata->pid_mutex);
1893
1894                 break;
1895         }
1896         default:
1897                 /* TODO: Userspace tracing */
1898                 ret = LTTNG_ERR_UND;
1899                 goto error;
1900         }
1901
1902         return LTTNG_OK;
1903
1904 error:
1905         if (socket) {
1906                 consumer_destroy_socket(socket);
1907         }
1908         return ret;
1909 }
1910
1911 /*
1912  * Command LTTNG_LIST_DOMAINS processed by the client thread.
1913  */
1914 ssize_t cmd_list_domains(struct ltt_session *session,
1915                 struct lttng_domain **domains)
1916 {
1917         int ret, index = 0;
1918         ssize_t nb_dom = 0;
1919
1920         if (session->kernel_session != NULL) {
1921                 DBG3("Listing domains found kernel domain");
1922                 nb_dom++;
1923         }
1924
1925         if (session->ust_session != NULL) {
1926                 DBG3("Listing domains found UST global domain");
1927                 nb_dom++;
1928         }
1929
1930         *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
1931         if (*domains == NULL) {
1932                 ret = LTTNG_ERR_FATAL;
1933                 goto error;
1934         }
1935
1936         if (session->kernel_session != NULL) {
1937                 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
1938                 index++;
1939         }
1940
1941         if (session->ust_session != NULL) {
1942                 (*domains)[index].type = LTTNG_DOMAIN_UST;
1943                 (*domains)[index].buf_type = session->ust_session->buffer_type;
1944                 index++;
1945         }
1946
1947         return nb_dom;
1948
1949 error:
1950         /* Return negative value to differentiate return code */
1951         return -ret;
1952 }
1953
1954
1955 /*
1956  * Command LTTNG_LIST_CHANNELS processed by the client thread.
1957  */
1958 ssize_t cmd_list_channels(int domain, struct ltt_session *session,
1959                 struct lttng_channel **channels)
1960 {
1961         int ret;
1962         ssize_t nb_chan = 0;
1963
1964         switch (domain) {
1965         case LTTNG_DOMAIN_KERNEL:
1966                 if (session->kernel_session != NULL) {
1967                         nb_chan = session->kernel_session->channel_count;
1968                 }
1969                 DBG3("Number of kernel channels %zd", nb_chan);
1970                 if (nb_chan <= 0) {
1971                         ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1972                 }
1973                 break;
1974         case LTTNG_DOMAIN_UST:
1975                 if (session->ust_session != NULL) {
1976                         nb_chan = lttng_ht_get_count(
1977                                         session->ust_session->domain_global.channels);
1978                 }
1979                 DBG3("Number of UST global channels %zd", nb_chan);
1980                 if (nb_chan <= 0) {
1981                         ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1982                 }
1983                 break;
1984         default:
1985                 *channels = NULL;
1986                 ret = LTTNG_ERR_UND;
1987                 goto error;
1988         }
1989
1990         if (nb_chan > 0) {
1991                 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
1992                 if (*channels == NULL) {
1993                         ret = LTTNG_ERR_FATAL;
1994                         goto error;
1995                 }
1996
1997                 list_lttng_channels(domain, session, *channels);
1998         } else {
1999                 *channels = NULL;
2000                 /* Ret value was set in the domain switch case */
2001                 goto error;
2002         }
2003
2004         return nb_chan;
2005
2006 error:
2007         /* Return negative value to differentiate return code */
2008         return -ret;
2009 }
2010
2011 /*
2012  * Command LTTNG_LIST_EVENTS processed by the client thread.
2013  */
2014 ssize_t cmd_list_events(int domain, struct ltt_session *session,
2015                 char *channel_name, struct lttng_event **events)
2016 {
2017         int ret = 0;
2018         ssize_t nb_event = 0;
2019
2020         switch (domain) {
2021         case LTTNG_DOMAIN_KERNEL:
2022                 if (session->kernel_session != NULL) {
2023                         nb_event = list_lttng_kernel_events(channel_name,
2024                                         session->kernel_session, events);
2025                 }
2026                 break;
2027         case LTTNG_DOMAIN_UST:
2028         {
2029                 if (session->ust_session != NULL) {
2030                         nb_event = list_lttng_ust_global_events(channel_name,
2031                                         &session->ust_session->domain_global, events);
2032                 }
2033                 break;
2034         }
2035         default:
2036                 ret = LTTNG_ERR_UND;
2037                 goto error;
2038         }
2039
2040         return nb_event;
2041
2042 error:
2043         /* Return negative value to differentiate return code */
2044         return -ret;
2045 }
2046
2047 /*
2048  * Using the session list, filled a lttng_session array to send back to the
2049  * client for session listing.
2050  *
2051  * The session list lock MUST be acquired before calling this function. Use
2052  * session_lock_list() and session_unlock_list().
2053  */
2054 void cmd_list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2055                 gid_t gid)
2056 {
2057         int ret;
2058         unsigned int i = 0;
2059         struct ltt_session *session;
2060         struct ltt_session_list *list = session_get_list();
2061
2062         DBG("Getting all available session for UID %d GID %d",
2063                         uid, gid);
2064         /*
2065          * Iterate over session list and append data after the control struct in
2066          * the buffer.
2067          */
2068         cds_list_for_each_entry(session, &list->head, list) {
2069                 /*
2070                  * Only list the sessions the user can control.
2071                  */
2072                 if (!session_access_ok(session, uid, gid)) {
2073                         continue;
2074                 }
2075
2076                 struct ltt_kernel_session *ksess = session->kernel_session;
2077                 struct ltt_ust_session *usess = session->ust_session;
2078
2079                 if (session->consumer->type == CONSUMER_DST_NET ||
2080                                 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
2081                                 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
2082                         ret = build_network_session_path(sessions[i].path,
2083                                         sizeof(sessions[i].path), session);
2084                 } else {
2085                         ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
2086                                         session->consumer->dst.trace_path);
2087                 }
2088                 if (ret < 0) {
2089                         PERROR("snprintf session path");
2090                         continue;
2091                 }
2092
2093                 strncpy(sessions[i].name, session->name, NAME_MAX);
2094                 sessions[i].name[NAME_MAX - 1] = '\0';
2095                 sessions[i].enabled = session->enabled;
2096                 i++;
2097         }
2098 }
2099
2100 /*
2101  * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
2102  * ready for trace analysis (or anykind of reader) or else 1 for pending data.
2103  */
2104 int cmd_data_pending(struct ltt_session *session)
2105 {
2106         int ret;
2107         struct ltt_kernel_session *ksess = session->kernel_session;
2108         struct ltt_ust_session *usess = session->ust_session;
2109
2110         assert(session);
2111
2112         /* Session MUST be stopped to ask for data availability. */
2113         if (session->enabled) {
2114                 ret = LTTNG_ERR_SESSION_STARTED;
2115                 goto error;
2116         }
2117
2118         if (ksess && ksess->consumer) {
2119                 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
2120                 if (ret == 1) {
2121                         /* Data is still being extracted for the kernel. */
2122                         goto error;
2123                 }
2124         }
2125
2126         if (usess && usess->consumer) {
2127                 ret = consumer_is_data_pending(usess->id, usess->consumer);
2128                 if (ret == 1) {
2129                         /* Data is still being extracted for the kernel. */
2130                         goto error;
2131                 }
2132         }
2133
2134         /* Data is ready to be read by a viewer */
2135         ret = 0;
2136
2137 error:
2138         return ret;
2139 }
2140
2141 /*
2142  * Init command subsystem.
2143  */
2144 void cmd_init(void)
2145 {
2146         /*
2147          * Set network sequence index to 1 for streams to match a relayd
2148          * socket on the consumer side.
2149          */
2150         pthread_mutex_lock(&relayd_net_seq_idx_lock);
2151         relayd_net_seq_idx = 1;
2152         pthread_mutex_unlock(&relayd_net_seq_idx_lock);
2153
2154         DBG("Command subsystem initialized");
2155 }