lttng-sessiond/ust-app.c

   1 /*
   2  * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; only version 2
   7  * of the License.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  17  */
  18
  19 #define _GNU_SOURCE
  20 #include <errno.h>
  21 #include <pthread.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <sys/stat.h>
  26 #include <sys/types.h>
  27 #include <unistd.h>
  28
  29 #include <urcu/compiler.h>
  30 #include <lttngerr.h>
  31 #include <lttng-share.h>
  32
  33 #include "hashtable.h"
  34 #include "ust-app.h"
  35 #include "ust-consumer.h"
  36 #include "ust-ctl.h"
  37
  38 /*
  39  * Delete ust context safely. RCU read lock must be held before calling
  40  * this function.
  41  */
  42 static
  43 void delete_ust_app_ctx(int sock, struct ust_app_ctx *ua_ctx)
  44 {
  45         if (ua_ctx->obj) {
  46                 ustctl_release_object(sock, ua_ctx->obj);
  47                 free(ua_ctx->obj);
  48         }
  49         free(ua_ctx);
  50 }
  51
  52 /*
  53  * Delete ust app event safely. RCU read lock must be held before calling
  54  * this function.
  55  */
  56 static
  57 void delete_ust_app_event(int sock, struct ust_app_event *ua_event)
  58 {
  59         int ret;
  60         struct cds_lfht_iter iter;
  61         struct ust_app_ctx *ua_ctx;
  62
  63         cds_lfht_for_each_entry(ua_event->ctx, &iter, ua_ctx, node) {
  64                 ret = hashtable_del(ua_event->ctx, &iter);
  65                 assert(!ret);
  66                 delete_ust_app_ctx(sock, ua_ctx);
  67         }
  68         ret = hashtable_destroy(ua_event->ctx);
  69         assert(!ret);
  70
  71         if (ua_event->obj != NULL) {
  72                 ustctl_release_object(sock, ua_event->obj);
  73                 free(ua_event->obj);
  74         }
  75         free(ua_event);
  76 }
  77
  78 /*
  79  * Delete ust app stream safely. RCU read lock must be held before calling
  80  * this function.
  81  */
  82 static
  83 void delete_ust_app_stream(int sock, struct ltt_ust_stream *stream)
  84 {
  85         if (stream->obj) {
  86                 ustctl_release_object(sock, stream->obj);
  87                 free(stream->obj);
  88         }
  89         free(stream);
  90 }
  91
  92 /*
  93  * Delete ust app channel safely. RCU read lock must be held before calling
  94  * this function.
  95  */
  96 static
  97 void delete_ust_app_channel(int sock, struct ust_app_channel *ua_chan)
  98 {
  99         int ret;
 100         struct cds_lfht_iter iter;
 101         struct ust_app_event *ua_event;
 102         struct ust_app_ctx *ua_ctx;
 103         struct ltt_ust_stream *stream, *stmp;
 104
 105         /* Wipe stream */
 106         cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
 107                 cds_list_del(&stream->list);
 108                 delete_ust_app_stream(sock, stream);
 109         }
 110
 111         /* Wipe context */
 112         cds_lfht_for_each_entry(ua_chan->ctx, &iter, ua_ctx, node) {
 113                 ret = hashtable_del(ua_chan->ctx, &iter);
 114                 assert(!ret);
 115                 delete_ust_app_ctx(sock, ua_ctx);
 116         }
 117         ret = hashtable_destroy(ua_chan->ctx);
 118         assert(!ret);
 119
 120         /* Wipe events */
 121         cds_lfht_for_each_entry(ua_chan->events, &iter, ua_event, node) {
 122                 ret = hashtable_del(ua_chan->events, &iter);
 123                 assert(!ret);
 124                 delete_ust_app_event(sock, ua_event);
 125         }
 126         ret = hashtable_destroy(ua_chan->events);
 127         assert(!ret);
 128
 129         if (ua_chan->obj != NULL) {
 130                 ustctl_release_object(sock, ua_chan->obj);
 131                 free(ua_chan->obj);
 132         }
 133         free(ua_chan);
 134 }
 135
 136 /*
 137  * Delete ust app session safely. RCU read lock must be held before calling
 138  * this function.
 139  */
 140 static
 141 void delete_ust_app_session(int sock, struct ust_app_session *ua_sess)
 142 {
 143         int ret;
 144         struct cds_lfht_iter iter;
 145         struct ust_app_channel *ua_chan;
 146
 147         if (ua_sess->metadata) {
 148                 if (ua_sess->metadata->stream_obj) {
 149                         ustctl_release_object(sock, ua_sess->metadata->stream_obj);
 150                         free(ua_sess->metadata->stream_obj);
 151                 }
 152                 if (ua_sess->metadata->obj) {
 153                         ustctl_release_object(sock, ua_sess->metadata->obj);
 154                         free(ua_sess->metadata->obj);
 155                 }
 156         }
 157
 158         cds_lfht_for_each_entry(ua_sess->channels, &iter, ua_chan, node) {
 159                 ret = hashtable_del(ua_sess->channels, &iter);
 160                 assert(!ret);
 161                 delete_ust_app_channel(sock, ua_chan);
 162         }
 163         ret = hashtable_destroy(ua_sess->channels);
 164         assert(!ret);
 165
 166         free(ua_sess);
 167 }
 168
 169 /*
 170  * Delete a traceable application structure from the global list. Never call
 171  * this function outside of a call_rcu call.
 172  */
 173 static
 174 void delete_ust_app(struct ust_app *app)
 175 {
 176         int ret, sock;
 177         struct cds_lfht_node *node;
 178         struct cds_lfht_iter iter;
 179         struct ust_app_session *ua_sess;
 180
 181         rcu_read_lock();
 182
 183         /* Remove from key hash table */
 184         node = hashtable_lookup(ust_app_sock_key_map,
 185                         (void *) ((unsigned long) app->key.sock), sizeof(void *), &iter);
 186         if (node == NULL) {
 187                 /* Not suppose to happen */
 188                 ERR("UST app key %d not found in key hash table", app->key.sock);
 189                 goto end;
 190         }
 191
 192         ret = hashtable_del(ust_app_sock_key_map, &iter);
 193         if (ret) {
 194                 ERR("UST app unable to delete app sock %d from key hash table",
 195                                 app->key.sock);
 196         } else {
 197                 DBG2("UST app pair sock %d key %d deleted",
 198                                 app->key.sock, app->key.pid);
 199         }
 200
 201         /* Socket is already closed at this point */
 202
 203         /* Delete ust app sessions info */
 204         sock = app->key.sock;
 205         app->key.sock = -1;
 206
 207         /* Wipe sessions */
 208         cds_lfht_for_each_entry(app->sessions, &iter, ua_sess, node) {
 209                 ret = hashtable_del(app->sessions, &iter);
 210                 assert(!ret);
 211                 delete_ust_app_session(app->key.sock, ua_sess);
 212         }
 213         ret = hashtable_destroy(app->sessions);
 214         assert(!ret);
 215
 216         /*
 217          * Wait until we have removed the key from the sock hash table
 218          * before closing this socket, otherwise an application could
 219          * re-use the socket ID and race with the teardown, using the
 220          * same hash table entry.
 221          */
 222         close(sock);
 223
 224         DBG2("UST app pid %d deleted", app->key.pid);
 225         free(app);
 226 end:
 227         rcu_read_unlock();
 228 }
 229
 230 /*
 231  * URCU intermediate call to delete an UST app.
 232  */
 233 static
 234 void delete_ust_app_rcu(struct rcu_head *head)
 235 {
 236         struct cds_lfht_node *node =
 237                 caa_container_of(head, struct cds_lfht_node, head);
 238         struct ust_app *app =
 239                 caa_container_of(node, struct ust_app, node);
 240
 241         delete_ust_app(app);
 242 }
 243
 244 /*
 245  * Alloc new UST app session.
 246  */
 247 static
 248 struct ust_app_session *alloc_ust_app_session(void)
 249 {
 250         struct ust_app_session *ua_sess;
 251
 252         /* Init most of the default value by allocating and zeroing */
 253         ua_sess = zmalloc(sizeof(struct ust_app_session));
 254         if (ua_sess == NULL) {
 255                 PERROR("malloc");
 256                 goto error;
 257         }
 258
 259         ua_sess->handle = -1;
 260         ua_sess->channels = hashtable_new_str(0);
 261
 262         return ua_sess;
 263
 264 error:
 265         return NULL;
 266 }
 267
 268 /*
 269  * Alloc new UST app channel.
 270  */
 271 static
 272 struct ust_app_channel *alloc_ust_app_channel(char *name,
 273                 struct lttng_ust_channel *attr)
 274 {
 275         struct ust_app_channel *ua_chan;
 276
 277         /* Init most of the default value by allocating and zeroing */
 278         ua_chan = zmalloc(sizeof(struct ust_app_channel));
 279         if (ua_chan == NULL) {
 280                 PERROR("malloc");
 281                 goto error;
 282         }
 283
 284         /* Setup channel name */
 285         strncpy(ua_chan->name, name, sizeof(ua_chan->name));
 286         ua_chan->name[sizeof(ua_chan->name) - 1] = '\0';
 287
 288         ua_chan->enabled = 1;
 289         ua_chan->handle = -1;
 290         ua_chan->ctx = hashtable_new(0);
 291         ua_chan->events = hashtable_new_str(0);
 292         hashtable_node_init(&ua_chan->node, (void *) ua_chan->name,
 293                         strlen(ua_chan->name));
 294
 295         CDS_INIT_LIST_HEAD(&ua_chan->streams.head);
 296
 297         /* Copy attributes */
 298         if (attr) {
 299                 memcpy(&ua_chan->attr, attr, sizeof(ua_chan->attr));
 300         }
 301
 302         DBG3("UST app channel %s allocated", ua_chan->name);
 303
 304         return ua_chan;
 305
 306 error:
 307         return NULL;
 308 }
 309
 310 /*
 311  * Alloc new UST app event.
 312  */
 313 static
 314 struct ust_app_event *alloc_ust_app_event(char *name,
 315                 struct lttng_ust_event *attr)
 316 {
 317         struct ust_app_event *ua_event;
 318
 319         /* Init most of the default value by allocating and zeroing */
 320         ua_event = zmalloc(sizeof(struct ust_app_event));
 321         if (ua_event == NULL) {
 322                 PERROR("malloc");
 323                 goto error;
 324         }
 325
 326         ua_event->enabled = 1;
 327         strncpy(ua_event->name, name, sizeof(ua_event->name));
 328         ua_event->name[sizeof(ua_event->name) - 1] = '\0';
 329         ua_event->ctx = hashtable_new(0);
 330         hashtable_node_init(&ua_event->node, (void *) ua_event->name,
 331                         strlen(ua_event->name));
 332
 333         /* Copy attributes */
 334         if (attr) {
 335                 memcpy(&ua_event->attr, attr, sizeof(ua_event->attr));
 336         }
 337
 338         DBG3("UST app event %s allocated", ua_event->name);
 339
 340         return ua_event;
 341
 342 error:
 343         return NULL;
 344 }
 345
 346 /*
 347  * Alloc new UST app context.
 348  */
 349 static
 350 struct ust_app_ctx *alloc_ust_app_ctx(struct lttng_ust_context *uctx)
 351 {
 352         struct ust_app_ctx *ua_ctx;
 353
 354         ua_ctx = zmalloc(sizeof(struct ust_app_ctx));
 355         if (ua_ctx == NULL) {
 356                 goto error;
 357         }
 358
 359         if (uctx) {
 360                 memcpy(&ua_ctx->ctx, uctx, sizeof(ua_ctx->ctx));
 361         }
 362
 363         DBG3("UST app context %d allocated", ua_ctx->ctx.ctx);
 364
 365 error:
 366         return ua_ctx;
 367 }
 368
 369 /*
 370  * Find an ust_app using the sock and return it. RCU read side lock must be
 371  * held before calling this helper function.
 372  */
 373 static
 374 struct ust_app *find_app_by_sock(int sock)
 375 {
 376         struct cds_lfht_node *node;
 377         struct ust_app_key *key;
 378         struct cds_lfht_iter iter;
 379
 380         node = hashtable_lookup(ust_app_sock_key_map,
 381                         (void *)((unsigned long) sock), sizeof(void *), &iter);
 382         if (node == NULL) {
 383                 DBG2("UST app find by sock %d key not found", sock);
 384                 goto error;
 385         }
 386
 387         key = caa_container_of(node, struct ust_app_key, node);
 388
 389         node = hashtable_lookup(ust_app_ht,
 390                         (void *)((unsigned long) key->pid), sizeof(void *), &iter);
 391         if (node == NULL) {
 392                 DBG2("UST app find by sock %d not found", sock);
 393                 goto error;
 394         }
 395         return caa_container_of(node, struct ust_app, node);
 396
 397 error:
 398         return NULL;
 399 }
 400
 401 /*
 402  * Create the channel context on the tracer.
 403  */
 404 static
 405 int create_ust_channel_context(struct ust_app_channel *ua_chan,
 406                 struct ust_app_ctx *ua_ctx, struct ust_app *app)
 407 {
 408         int ret;
 409
 410         ret = ustctl_add_context(app->key.sock, &ua_ctx->ctx,
 411                         ua_chan->obj, &ua_ctx->obj);
 412         if (ret < 0) {
 413                 goto error;
 414         }
 415
 416         ua_ctx->handle = ua_ctx->obj->handle;
 417
 418         DBG2("UST app context added to channel %s successfully", ua_chan->name);
 419
 420 error:
 421         return ret;
 422 }
 423
 424 /*
 425  * Create the event context on the tracer.
 426  */
 427 static
 428 int create_ust_event_context(struct ust_app_event *ua_event,
 429                 struct ust_app_ctx *ua_ctx, struct ust_app *app)
 430 {
 431         int ret;
 432
 433         ret = ustctl_add_context(app->key.sock, &ua_ctx->ctx,
 434                         ua_event->obj, &ua_ctx->obj);
 435         if (ret < 0) {
 436                 goto error;
 437         }
 438
 439         ua_ctx->handle = ua_ctx->obj->handle;
 440
 441         DBG2("UST app context added to event %s successfully", ua_event->name);
 442
 443 error:
 444         return ret;
 445 }
 446
 447 /*
 448  * Disable the specified event on to UST tracer for the UST session.
 449  */
 450 static int disable_ust_event(struct ust_app *app,
 451                 struct ust_app_session *ua_sess, struct ust_app_event *ua_event)
 452 {
 453         int ret;
 454
 455         ret = ustctl_disable(app->key.sock, ua_event->obj);
 456         if (ret < 0) {
 457                 ERR("UST app event %s disable failed for app (pid: %d) "
 458                                 "and session handle %d with ret %d",
 459                                 ua_event->attr.name, app->key.pid, ua_sess->handle, ret);
 460                 goto error;
 461         }
 462
 463         DBG2("UST app event %s disabled successfully for app (pid: %d)",
 464                         ua_event->attr.name, app->key.pid);
 465
 466 error:
 467         return ret;
 468 }
 469
 470 /*
 471  * Disable the specified channel on to UST tracer for the UST session.
 472  */
 473 static int disable_ust_channel(struct ust_app *app,
 474                 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
 475 {
 476         int ret;
 477
 478         ret = ustctl_disable(app->key.sock, ua_chan->obj);
 479         if (ret < 0) {
 480                 ERR("UST app channel %s disable failed for app (pid: %d) "
 481                                 "and session handle %d with ret %d",
 482                                 ua_chan->name, app->key.pid, ua_sess->handle, ret);
 483                 goto error;
 484         }
 485
 486         DBG2("UST app channel %s disabled successfully for app (pid: %d)",
 487                         ua_chan->name, app->key.pid);
 488
 489 error:
 490         return ret;
 491 }
 492
 493 /*
 494  * Enable the specified channel on to UST tracer for the UST session.
 495  */
 496 static int enable_ust_channel(struct ust_app *app,
 497                 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
 498 {
 499         int ret;
 500
 501         ret = ustctl_enable(app->key.sock, ua_chan->obj);
 502         if (ret < 0) {
 503                 ERR("UST app channel %s enable failed for app (pid: %d) "
 504                                 "and session handle %d with ret %d",
 505                                 ua_chan->name, app->key.pid, ua_sess->handle, ret);
 506                 goto error;
 507         }
 508
 509         ua_chan->enabled = 1;
 510
 511         DBG2("UST app channel %s enabled successfully for app (pid: %d)",
 512                         ua_chan->name, app->key.pid);
 513
 514 error:
 515         return ret;
 516 }
 517
 518 /*
 519  * Enable the specified event on to UST tracer for the UST session.
 520  */
 521 static int enable_ust_event(struct ust_app *app,
 522                 struct ust_app_session *ua_sess, struct ust_app_event *ua_event)
 523 {
 524         int ret;
 525
 526         ret = ustctl_enable(app->key.sock, ua_event->obj);
 527         if (ret < 0) {
 528                 ERR("UST app event %s enable failed for app (pid: %d) "
 529                                 "and session handle %d with ret %d",
 530                                 ua_event->attr.name, app->key.pid, ua_sess->handle, ret);
 531                 goto error;
 532         }
 533
 534         DBG2("UST app event %s enabled successfully for app (pid: %d)",
 535                         ua_event->attr.name, app->key.pid);
 536
 537 error:
 538         return ret;
 539 }
 540
 541 /*
 542  * Open metadata onto the UST tracer for a UST session.
 543  */
 544 static int open_ust_metadata(struct ust_app *app,
 545                 struct ust_app_session *ua_sess)
 546 {
 547         int ret;
 548         struct lttng_ust_channel_attr uattr;
 549
 550         uattr.overwrite = ua_sess->metadata->attr.overwrite;
 551         uattr.subbuf_size = ua_sess->metadata->attr.subbuf_size;
 552         uattr.num_subbuf = ua_sess->metadata->attr.num_subbuf;
 553         uattr.switch_timer_interval =
 554                 ua_sess->metadata->attr.switch_timer_interval;
 555         uattr.read_timer_interval =
 556                 ua_sess->metadata->attr.read_timer_interval;
 557         uattr.output = ua_sess->metadata->attr.output;
 558
 559         /* UST tracer metadata creation */
 560         ret = ustctl_open_metadata(app->key.sock, ua_sess->handle, &uattr,
 561                         &ua_sess->metadata->obj);
 562         if (ret < 0) {
 563                 ERR("UST app open metadata failed for app pid:%d",
 564                                 app->key.pid);
 565                 goto error;
 566         }
 567
 568 error:
 569         return ret;
 570 }
 571
 572 /*
 573  * Create stream onto the UST tracer for a UST session.
 574  */
 575 static int create_ust_stream(struct ust_app *app,
 576                 struct ust_app_session *ua_sess)
 577 {
 578         int ret;
 579
 580         ret = ustctl_create_stream(app->key.sock, ua_sess->metadata->obj,
 581                         &ua_sess->metadata->stream_obj);
 582         if (ret < 0) {
 583                 ERR("UST create metadata stream failed");
 584                 goto error;
 585         }
 586
 587 error:
 588         return ret;
 589 }
 590
 591 /*
 592  * Create the specified channel onto the UST tracer for a UST session.
 593  */
 594 static int create_ust_channel(struct ust_app *app,
 595                 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
 596 {
 597         int ret;
 598
 599         /* TODO: remove cast and use lttng-ust-abi.h */
 600         ret = ustctl_create_channel(app->key.sock, ua_sess->handle,
 601                         (struct lttng_ust_channel_attr *)&ua_chan->attr, &ua_chan->obj);
 602         if (ret < 0) {
 603                 DBG("Error creating channel %s for app (pid: %d, sock: %d) "
 604                                 "and session handle %d with ret %d",
 605                                 ua_chan->name, app->key.pid, app->key.sock,
 606                                 ua_sess->handle, ret);
 607                 goto error;
 608         }
 609
 610         ua_chan->handle = ua_chan->obj->handle;
 611         ua_chan->attr.shm_fd = ua_chan->obj->shm_fd;
 612         ua_chan->attr.wait_fd = ua_chan->obj->wait_fd;
 613         ua_chan->attr.memory_map_size = ua_chan->obj->memory_map_size;
 614
 615         DBG2("UST app channel %s created successfully for pid:%d and sock:%d",
 616                         ua_chan->name, app->key.pid, app->key.sock);
 617
 618         /* If channel is not enabled, disable it on the tracer */
 619         if (!ua_chan->enabled) {
 620                 ret = disable_ust_channel(app, ua_sess, ua_chan);
 621                 if (ret < 0) {
 622                         goto error;
 623                 }
 624         }
 625
 626 error:
 627         return ret;
 628 }
 629
 630 /*
 631  * Create the specified event onto the UST tracer for a UST session.
 632  */
 633 static
 634 int create_ust_event(struct ust_app *app, struct ust_app_session *ua_sess,
 635                 struct ust_app_channel *ua_chan, struct ust_app_event *ua_event)
 636 {
 637         int ret = 0;
 638
 639         /* Create UST event on tracer */
 640         ret = ustctl_create_event(app->key.sock, &ua_event->attr, ua_chan->obj,
 641                         &ua_event->obj);
 642         if (ret < 0) {
 643                 ERR("Error ustctl create event %s for app pid: %d with ret %d",
 644                                 ua_event->attr.name, app->key.pid, ret);
 645                 goto error;
 646         }
 647
 648         ua_event->handle = ua_event->obj->handle;
 649
 650         DBG2("UST app event %s created successfully for pid:%d",
 651                         ua_event->attr.name, app->key.pid);
 652
 653         /* If event not enabled, disable it on the tracer */
 654         if (!ua_event->enabled) {
 655                 ret = disable_ust_event(app, ua_sess, ua_event);
 656                 if (ret < 0) {
 657                         goto error;
 658                 }
 659         }
 660
 661 error:
 662         return ret;
 663 }
 664
 665 /*
 666  * Copy data between an UST app event and a LTT event.
 667  */
 668 static void shadow_copy_event(struct ust_app_event *ua_event,
 669                 struct ltt_ust_event *uevent)
 670 {
 671         struct cds_lfht_iter iter;
 672         struct ltt_ust_context *uctx;
 673         struct ust_app_ctx *ua_ctx;
 674
 675         strncpy(ua_event->name, uevent->attr.name, sizeof(ua_event->name));
 676         ua_event->name[sizeof(ua_event->name) - 1] = '\0';
 677
 678         /* Copy event attributes */
 679         memcpy(&ua_event->attr, &uevent->attr, sizeof(ua_event->attr));
 680
 681         cds_lfht_for_each_entry(uevent->ctx, &iter, uctx, node) {
 682                 ua_ctx = alloc_ust_app_ctx(&uctx->ctx);
 683                 if (ua_ctx == NULL) {
 684                         continue;
 685                 }
 686                 hashtable_node_init(&ua_ctx->node,
 687                                 (void *)((unsigned long) ua_ctx->ctx.ctx), sizeof(void *));
 688                 hashtable_add_unique(ua_event->ctx, &ua_ctx->node);
 689         }
 690 }
 691
 692 /*
 693  * Copy data between an UST app channel and a LTT channel.
 694  */
 695 static void shadow_copy_channel(struct ust_app_channel *ua_chan,
 696                 struct ltt_ust_channel *uchan)
 697 {
 698         struct cds_lfht_iter iter;
 699         struct cds_lfht_node *ua_event_node;
 700         struct ltt_ust_event *uevent;
 701         struct ltt_ust_context *uctx;
 702         struct ust_app_event *ua_event;
 703         struct ust_app_ctx *ua_ctx;
 704
 705         DBG2("Shadow copy of UST app channel %s", ua_chan->name);
 706
 707         strncpy(ua_chan->name, uchan->name, sizeof(ua_chan->name));
 708         ua_chan->name[sizeof(ua_chan->name) - 1] = '\0';
 709         /* Copy event attributes */
 710         memcpy(&ua_chan->attr, &uchan->attr, sizeof(ua_chan->attr));
 711
 712         cds_lfht_for_each_entry(uchan->ctx, &iter, uctx, node) {
 713                 ua_ctx = alloc_ust_app_ctx(&uctx->ctx);
 714                 if (ua_ctx == NULL) {
 715                         continue;
 716                 }
 717                 hashtable_node_init(&ua_ctx->node,
 718                                 (void *)((unsigned long) ua_ctx->ctx.ctx), sizeof(void *));
 719                 hashtable_add_unique(ua_chan->ctx, &ua_ctx->node);
 720         }
 721
 722         /* Copy all events from ltt ust channel to ust app channel */
 723         cds_lfht_for_each_entry(uchan->events, &iter, uevent, node) {
 724                 struct cds_lfht_iter uiter;
 725
 726                 ua_event_node = hashtable_lookup(ua_chan->events,
 727                                 (void *) uevent->attr.name, strlen(uevent->attr.name),
 728                                 &uiter);
 729                 if (ua_event_node == NULL) {
 730                         DBG2("UST event %s not found on shadow copy channel",
 731                                         uevent->attr.name);
 732                         ua_event = alloc_ust_app_event(uevent->attr.name, &uevent->attr);
 733                         if (ua_event == NULL) {
 734                                 continue;
 735                         }
 736                         shadow_copy_event(ua_event, uevent);
 737                         hashtable_add_unique(ua_chan->events, &ua_event->node);
 738                 }
 739         }
 740
 741         DBG3("Shadow copy channel done");
 742 }
 743
 744 /*
 745  * Copy data between a UST app session and a regular LTT session.
 746  */
 747 static void shadow_copy_session(struct ust_app_session *ua_sess,
 748                 struct ltt_ust_session *usess,
 749                 struct ust_app *app)
 750 {
 751         struct cds_lfht_node *ua_chan_node;
 752         struct cds_lfht_iter iter;
 753         struct ltt_ust_channel *uchan;
 754         struct ust_app_channel *ua_chan;
 755         time_t rawtime;
 756         struct tm *timeinfo;
 757         char datetime[16];
 758         int ret;
 759
 760         /* Get date and time for unique app path */
 761         time(&rawtime);
 762         timeinfo = localtime(&rawtime);
 763         strftime(datetime, sizeof(datetime), "%Y%m%d-%H%M%S", timeinfo);
 764
 765         DBG2("Shadow copy of session handle %d", ua_sess->handle);
 766
 767         ua_sess->uid = usess->uid;
 768
 769         ret = snprintf(ua_sess->path, PATH_MAX,
 770                         "%s/%s-%d-%s",
 771                         usess->pathname, app->name, app->key.pid,
 772                         datetime);
 773         if (ret < 0) {
 774                 PERROR("asprintf UST shadow copy session");
 775                 /* TODO: We cannot return an error from here.. */
 776                 assert(0);
 777         }
 778
 779         /* TODO: support all UST domain */
 780
 781         /* Iterate over all channels in global domain. */
 782         cds_lfht_for_each_entry(usess->domain_global.channels, &iter,
 783                         uchan, node) {
 784                 struct cds_lfht_iter uiter;
 785
 786                 ua_chan_node = hashtable_lookup(ua_sess->channels,
 787                                 (void *)uchan->name, strlen(uchan->name),
 788                                 &uiter);
 789                 if (ua_chan_node != NULL) {
 790                         continue;
 791                 }
 792
 793                 DBG2("Channel %s not found on shadow session copy, creating it",
 794                                 uchan->name);
 795                 ua_chan = alloc_ust_app_channel(uchan->name, &uchan->attr);
 796                 if (ua_chan == NULL) {
 797                         /* malloc failed... continuing */
 798                         continue;
 799                 }
 800
 801                 shadow_copy_channel(ua_chan, uchan);
 802                 hashtable_add_unique(ua_sess->channels, &ua_chan->node);
 803         }
 804 }
 805
 806 /*
 807  * Lookup sesison wrapper.
 808  */
 809 static
 810 void __lookup_session_by_app(struct ltt_ust_session *usess,
 811                         struct ust_app *app, struct cds_lfht_iter *iter)
 812 {
 813         /* Get right UST app session from app */
 814         (void) hashtable_lookup(app->sessions,
 815                         (void *) ((unsigned long) usess->uid), sizeof(void *),
 816                         iter);
 817 }
 818
 819 /*
 820  * Return ust app session from the app session hashtable using the UST session
 821  * uid.
 822  */
 823 static struct ust_app_session *lookup_session_by_app(
 824                 struct ltt_ust_session *usess, struct ust_app *app)
 825 {
 826         struct cds_lfht_iter iter;
 827         struct cds_lfht_node *node;
 828
 829         __lookup_session_by_app(usess, app, &iter);
 830         node = hashtable_iter_get_node(&iter);
 831         if (node == NULL) {
 832                 goto error;
 833         }
 834
 835         return caa_container_of(node, struct ust_app_session, node);
 836
 837 error:
 838         return NULL;
 839 }
 840
 841 /*
 842  * Create a UST session onto the tracer of app and add it the session
 843  * hashtable.
 844  *
 845  * Return ust app session or NULL on error.
 846  */
 847 static struct ust_app_session *create_ust_app_session(
 848                 struct ltt_ust_session *usess, struct ust_app *app)
 849 {
 850         int ret;
 851         struct ust_app_session *ua_sess;
 852
 853         ua_sess = lookup_session_by_app(usess, app);
 854         if (ua_sess == NULL) {
 855                 DBG2("UST app pid: %d session uid %d not found, creating it",
 856                                 app->key.pid, usess->uid);
 857                 ua_sess = alloc_ust_app_session();
 858                 if (ua_sess == NULL) {
 859                         /* Only malloc can failed so something is really wrong */
 860                         goto error;
 861                 }
 862                 shadow_copy_session(ua_sess, usess, app);
 863         }
 864
 865         if (ua_sess->handle == -1) {
 866                 ret = ustctl_create_session(app->key.sock);
 867                 if (ret < 0) {
 868                         ERR("Error creating session for app pid %d, sock %d",
 869                                         app->key.pid, app->key.sock);
 870                         /* TODO: free() ua_sess */
 871                         goto error;
 872                 }
 873
 874                 DBG2("UST app ustctl create session handle %d", ret);
 875                 ua_sess->handle = ret;
 876
 877                 /* Add ust app session to app's HT */
 878                 hashtable_node_init(&ua_sess->node,
 879                                 (void *)((unsigned long) ua_sess->uid), sizeof(void *));
 880                 hashtable_add_unique(app->sessions, &ua_sess->node);
 881
 882                 DBG2("UST app session created successfully with handle %d", ret);
 883         }
 884
 885         return ua_sess;
 886
 887 error:
 888         return NULL;
 889 }
 890
 891 /*
 892  * Create a context for the channel on the tracer.
 893  */
 894 static
 895 int create_ust_app_channel_context(struct ust_app_session *ua_sess,
 896                 struct ust_app_channel *ua_chan, struct lttng_ust_context *uctx,
 897                 struct ust_app *app)
 898 {
 899         int ret = 0;
 900         struct cds_lfht_iter iter;
 901         struct cds_lfht_node *node;
 902         struct ust_app_ctx *ua_ctx;
 903
 904         DBG2("UST app adding context to channel %s", ua_chan->name);
 905
 906         node = hashtable_lookup(ua_chan->ctx, (void *)((unsigned long)uctx->ctx),
 907                         sizeof(void *), &iter);
 908         if (node != NULL) {
 909                 ret = -EEXIST;
 910                 goto error;
 911         }
 912
 913         ua_ctx = alloc_ust_app_ctx(uctx);
 914         if (ua_ctx == NULL) {
 915                 /* malloc failed */
 916                 ret = -1;
 917                 goto error;
 918         }
 919
 920         hashtable_node_init(&ua_ctx->node,
 921                         (void *)((unsigned long) ua_ctx->ctx.ctx), sizeof(void *));
 922         hashtable_add_unique(ua_chan->ctx, &ua_ctx->node);
 923
 924         ret = create_ust_channel_context(ua_chan, ua_ctx, app);
 925         if (ret < 0) {
 926                 goto error;
 927         }
 928
 929 error:
 930         return ret;
 931 }
 932
 933 /*
 934  * Create an UST context and enable it for the event on the tracer.
 935  */
 936 static
 937 int create_ust_app_event_context(struct ust_app_session *ua_sess,
 938                 struct ust_app_event *ua_event, struct lttng_ust_context *uctx,
 939                 struct ust_app *app)
 940 {
 941         int ret = 0;
 942         struct cds_lfht_iter iter;
 943         struct cds_lfht_node *node;
 944         struct ust_app_ctx *ua_ctx;
 945
 946         DBG2("UST app adding context to event %s", ua_event->name);
 947
 948         node = hashtable_lookup(ua_event->ctx, (void *)((unsigned long)uctx->ctx),
 949                         sizeof(void *), &iter);
 950         if (node != NULL) {
 951                 ret = -EEXIST;
 952                 goto error;
 953         }
 954
 955         ua_ctx = alloc_ust_app_ctx(uctx);
 956         if (ua_ctx == NULL) {
 957                 /* malloc failed */
 958                 ret = -1;
 959                 goto error;
 960         }
 961
 962         hashtable_node_init(&ua_ctx->node,
 963                         (void *)((unsigned long) ua_ctx->ctx.ctx), sizeof(void *));
 964         hashtable_add_unique(ua_event->ctx, &ua_ctx->node);
 965
 966         ret = create_ust_event_context(ua_event, ua_ctx, app);
 967         if (ret < 0) {
 968                 goto error;
 969         }
 970
 971 error:
 972         return ret;
 973 }
 974
 975 /*
 976  * Enable on the tracer side a ust app event for the session and channel.
 977  */
 978 static
 979 int enable_ust_app_event(struct ust_app_session *ua_sess,
 980                 struct ust_app_event *ua_event, struct ust_app *app)
 981 {
 982         int ret;
 983
 984         ret = enable_ust_event(app, ua_sess, ua_event);
 985         if (ret < 0) {
 986                 goto error;
 987         }
 988
 989         ua_event->enabled = 1;
 990
 991 error:
 992         return ret;
 993 }
 994
 995 /*
 996  * Disable on the tracer side a ust app event for the session and channel.
 997  */
 998 static int disable_ust_app_event(struct ust_app_session *ua_sess,
 999                 struct ust_app_channel *ua_chan, struct ust_app_event *ua_event,
1000                 struct ust_app *app)
1001 {
1002         int ret;
1003
1004         ret = disable_ust_event(app, ua_sess, ua_event);
1005         if (ret < 0) {
1006                 goto error;
1007         }
1008
1009         ua_event->enabled = 0;
1010
1011 error:
1012         return ret;
1013 }
1014
1015 /*
1016  * Lookup ust app channel for session and disable it on the tracer side.
1017  */
1018 static
1019 int disable_ust_app_channel(struct ust_app_session *ua_sess,
1020                 struct ust_app_channel *ua_chan, struct ust_app *app)
1021 {
1022         int ret;
1023
1024         ret = disable_ust_channel(app, ua_sess, ua_chan);
1025         if (ret < 0) {
1026                 goto error;
1027         }
1028
1029         ua_chan->enabled = 0;
1030
1031 error:
1032         return ret;
1033 }
1034
1035 /*
1036  * Lookup ust app channel for session and enable it on the tracer side.
1037  */
1038 static int enable_ust_app_channel(struct ust_app_session *ua_sess,
1039                 struct ltt_ust_channel *uchan, struct ust_app *app)
1040 {
1041         int ret = 0;
1042         struct cds_lfht_iter iter;
1043         struct cds_lfht_node *ua_chan_node;
1044         struct ust_app_channel *ua_chan;
1045
1046         ua_chan_node = hashtable_lookup(ua_sess->channels,
1047                         (void *)uchan->name, strlen(uchan->name), &iter);
1048         if (ua_chan_node == NULL) {
1049                 DBG2("Unable to find channel %s in ust session uid %u",
1050                                 uchan->name, ua_sess->uid);
1051                 goto error;
1052         }
1053
1054         ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
1055
1056         ret = enable_ust_channel(app, ua_sess, ua_chan);
1057         if (ret < 0) {
1058                 goto error;
1059         }
1060
1061 error:
1062         return ret;
1063 }
1064
1065 /*
1066  * Create UST app channel and create it on the tracer.
1067  */
1068 static struct ust_app_channel *create_ust_app_channel(
1069                 struct ust_app_session *ua_sess, struct ltt_ust_channel *uchan,
1070                 struct ust_app *app)
1071 {
1072         int ret = 0;
1073         struct cds_lfht_iter iter;
1074         struct cds_lfht_node *ua_chan_node;
1075         struct ust_app_channel *ua_chan;
1076
1077         /* Lookup channel in the ust app session */
1078         ua_chan_node = hashtable_lookup(ua_sess->channels,
1079                         (void *)uchan->name, strlen(uchan->name), &iter);
1080         if (ua_chan_node == NULL) {
1081                 DBG2("Unable to find channel %s in ust session uid %u",
1082                                 uchan->name, ua_sess->uid);
1083                 ua_chan = alloc_ust_app_channel(uchan->name, &uchan->attr);
1084                 if (ua_chan == NULL) {
1085                         goto error;
1086                 }
1087                 shadow_copy_channel(ua_chan, uchan);
1088
1089                 hashtable_add_unique(ua_sess->channels, &ua_chan->node);
1090         } else {
1091                 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
1092         }
1093
1094         ret = create_ust_channel(app, ua_sess, ua_chan);
1095         if (ret < 0) {
1096                 goto error;
1097         }
1098
1099         return ua_chan;
1100
1101 error:
1102         return NULL;
1103 }
1104
1105 /*
1106  * Create UST app event and create it on the tracer side.
1107  */
1108 static
1109 int create_ust_app_event(struct ust_app_session *ua_sess,
1110                 struct ust_app_channel *ua_chan, struct ltt_ust_event *uevent,
1111                 struct ust_app *app)
1112 {
1113         int ret = 0;
1114         struct cds_lfht_iter iter;
1115         struct cds_lfht_node *ua_event_node;
1116         struct ust_app_event *ua_event;
1117
1118         /* Get event node */
1119         ua_event_node = hashtable_lookup(ua_chan->events,
1120                         (void *)uevent->attr.name, strlen(uevent->attr.name), &iter);
1121         if (ua_event_node != NULL) {
1122                 ERR("UST app event %s already exist. Stopping creation.",
1123                                 uevent->attr.name);
1124                 goto end;
1125         }
1126
1127         /* Does not exist so create one */
1128         ua_event = alloc_ust_app_event(uevent->attr.name, &uevent->attr);
1129         if (ua_event == NULL) {
1130                 /* Only malloc can failed so something is really wrong */
1131                 ret = -ENOMEM;
1132                 goto error;
1133         }
1134         shadow_copy_event(ua_event, uevent);
1135
1136         /* Create it on the tracer side */
1137         ret = create_ust_event(app, ua_sess, ua_chan, ua_event);
1138         if (ret < 0) {
1139                 rcu_read_lock();
1140                 delete_ust_app_event(app->key.sock, ua_event);
1141                 rcu_read_unlock();
1142                 goto error;
1143         }
1144
1145         ua_event->enabled = 1;
1146
1147         hashtable_add_unique(ua_chan->events, &ua_event->node);
1148
1149 end:
1150 error:
1151         return ret;
1152 }
1153
1154 /*
1155  * Create UST metadata and open it on the tracer side.
1156  */
1157 static int create_ust_app_metadata(struct ust_app_session *ua_sess,
1158                 char *pathname, struct ust_app *app)
1159 {
1160         int ret = 0;
1161
1162         if (ua_sess->metadata == NULL) {
1163                 /* Allocate UST metadata */
1164                 ua_sess->metadata = trace_ust_create_metadata(pathname);
1165                 if (ua_sess->metadata == NULL) {
1166                         ERR("UST app session %d creating metadata failed",
1167                                         ua_sess->handle);
1168                         goto error;
1169                 }
1170
1171                 ret = open_ust_metadata(app, ua_sess);
1172                 if (ret < 0) {
1173                         goto error;
1174                 }
1175
1176                 DBG2("UST metadata opened for app pid %d", app->key.pid);
1177         }
1178
1179         /* Open UST metadata stream */
1180         if (ua_sess->metadata->stream_obj == NULL) {
1181                 ret = create_ust_stream(app, ua_sess);
1182                 if (ret < 0) {
1183                         goto error;
1184                 }
1185
1186                 ret = mkdir(ua_sess->path, S_IRWXU | S_IRWXG);
1187                 if (ret < 0) {
1188                         PERROR("mkdir UST metadata");
1189                         goto error;
1190                 }
1191
1192                 ret = snprintf(ua_sess->metadata->pathname, PATH_MAX,
1193                                 "%s/metadata", ua_sess->path);
1194                 if (ret < 0) {
1195                         PERROR("asprintf UST create stream");
1196                         goto error;
1197                 }
1198
1199                 DBG2("UST metadata stream object created for app pid %d",
1200                                 app->key.pid);
1201         } else {
1202                 ERR("Attempting to create stream without metadata opened");
1203                 goto error;
1204         }
1205
1206         return 0;
1207
1208 error:
1209         return -1;
1210 }
1211
1212 /*
1213  * Return pointer to traceable apps list.
1214  */
1215 struct cds_lfht *ust_app_get_ht(void)
1216 {
1217         return ust_app_ht;
1218 }
1219
1220 /*
1221  * Return ust app pointer or NULL if not found.
1222  */
1223 struct ust_app *ust_app_find_by_pid(pid_t pid)
1224 {
1225         struct cds_lfht_node *node;
1226         struct cds_lfht_iter iter;
1227
1228         rcu_read_lock();
1229         node = hashtable_lookup(ust_app_ht,
1230                         (void *)((unsigned long) pid), sizeof(void *), &iter);
1231         if (node == NULL) {
1232                 DBG2("UST app no found with pid %d", pid);
1233                 goto error;
1234         }
1235         rcu_read_unlock();
1236
1237         DBG2("Found UST app by pid %d", pid);
1238
1239         return caa_container_of(node, struct ust_app, node);
1240
1241 error:
1242         rcu_read_unlock();
1243         return NULL;
1244 }
1245
1246 /*
1247  * Using pid and uid (of the app), allocate a new ust_app struct and
1248  * add it to the global traceable app list.
1249  *
1250  * On success, return 0, else return malloc -ENOMEM, or -EINVAL if app
1251  * bitness is not supported.
1252  */
1253 int ust_app_register(struct ust_register_msg *msg, int sock)
1254 {
1255         struct ust_app *lta;
1256
1257         if ((msg->bits_per_long == 64 && ust_consumerd64_fd == -EINVAL)
1258                         || (msg->bits_per_long == 32 && ust_consumerd32_fd == -EINVAL)) {
1259                 ERR("Registration failed: application \"%s\" (pid: %d) has "
1260                         "%d-bit long, but no consumerd for this long size is available.\n",
1261                         msg->name, msg->pid, msg->bits_per_long);
1262                 close(sock);
1263                 return -EINVAL;
1264         }
1265         lta = zmalloc(sizeof(struct ust_app));
1266         if (lta == NULL) {
1267                 PERROR("malloc");
1268                 return -ENOMEM;
1269         }
1270
1271         lta->ppid = msg->ppid;
1272         lta->uid = msg->uid;
1273         lta->gid = msg->gid;
1274         lta->bits_per_long = msg->bits_per_long;
1275         lta->v_major = msg->major;
1276         lta->v_minor = msg->minor;
1277         strncpy(lta->name, msg->name, sizeof(lta->name));
1278         lta->name[16] = '\0';
1279         lta->sessions = hashtable_new(0);
1280
1281         /* Set key map */
1282         lta->key.pid = msg->pid;
1283         hashtable_node_init(&lta->node, (void *)((unsigned long)lta->key.pid),
1284                         sizeof(void *));
1285         lta->key.sock = sock;
1286         hashtable_node_init(&lta->key.node, (void *)((unsigned long)lta->key.sock),
1287                         sizeof(void *));
1288
1289         rcu_read_lock();
1290         hashtable_add_unique(ust_app_sock_key_map, &lta->key.node);
1291         hashtable_add_unique(ust_app_ht, &lta->node);
1292         rcu_read_unlock();
1293
1294         DBG("App registered with pid:%d ppid:%d uid:%d gid:%d sock:%d name:%s"
1295                         " (version %d.%d)", lta->key.pid, lta->ppid, lta->uid, lta->gid,
1296                         lta->key.sock, lta->name, lta->v_major, lta->v_minor);
1297
1298         return 0;
1299 }
1300
1301 /*
1302  * Unregister app by removing it from the global traceable app list and freeing
1303  * the data struct.
1304  *
1305  * The socket is already closed at this point so no close to sock.
1306  */
1307 void ust_app_unregister(int sock)
1308 {
1309         struct ust_app *lta;
1310         struct cds_lfht_node *node;
1311         struct cds_lfht_iter iter;
1312         int ret;
1313
1314         rcu_read_lock();
1315         lta = find_app_by_sock(sock);
1316         if (lta == NULL) {
1317                 ERR("Unregister app sock %d not found!", sock);
1318                 goto error;
1319         }
1320
1321         DBG("PID %d unregistering with sock %d", lta->key.pid, sock);
1322
1323         /* Get the node reference for a call_rcu */
1324         node = hashtable_lookup(ust_app_ht,
1325                         (void *)((unsigned long) lta->key.pid), sizeof(void *), &iter);
1326         if (node == NULL) {
1327                 ERR("Unable to find app sock %d by pid %d", sock, lta->key.pid);
1328                 goto error;
1329         }
1330
1331         ret = hashtable_del(ust_app_ht, &iter);
1332         assert(!ret);
1333         call_rcu(&node->head, delete_ust_app_rcu);
1334 error:
1335         rcu_read_unlock();
1336         return;
1337 }
1338
1339 /*
1340  * Return traceable_app_count
1341  */
1342 unsigned long ust_app_list_count(void)
1343 {
1344         unsigned long count;
1345
1346         rcu_read_lock();
1347         count = hashtable_get_count(ust_app_ht);
1348         rcu_read_unlock();
1349
1350         return count;
1351 }
1352
1353 /*
1354  * Fill events array with all events name of all registered apps.
1355  */
1356 int ust_app_list_events(struct lttng_event **events)
1357 {
1358         int ret, handle;
1359         size_t nbmem, count = 0;
1360         struct cds_lfht_iter iter;
1361         struct ust_app *app;
1362         struct lttng_event *tmp;
1363
1364         nbmem = UST_APP_EVENT_LIST_SIZE;
1365         tmp = zmalloc(nbmem * sizeof(struct lttng_event));
1366         if (tmp == NULL) {
1367                 PERROR("zmalloc ust app events");
1368                 ret = -ENOMEM;
1369                 goto error;
1370         }
1371
1372         rcu_read_lock();
1373
1374         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
1375                 struct lttng_ust_tracepoint_iter iter;
1376
1377                 handle = ustctl_tracepoint_list(app->key.sock);
1378                 if (handle < 0) {
1379                         ERR("UST app list events getting handle failed for app pid %d",
1380                                         app->key.pid);
1381                         continue;
1382                 }
1383
1384                 while ((ret = ustctl_tracepoint_list_get(app->key.sock, handle,
1385                                                 &iter)) != -ENOENT) {
1386                         if (count >= nbmem) {
1387                                 DBG2("Reallocating event list from %zu to %zu entries", nbmem,
1388                                                 2 * nbmem);
1389                                 nbmem *= 2;
1390                                 tmp = realloc(tmp, nbmem * sizeof(struct lttng_event));
1391                                 if (tmp == NULL) {
1392                                         PERROR("realloc ust app events");
1393                                         ret = -ENOMEM;
1394                                         goto rcu_error;
1395                                 }
1396                         }
1397                         memcpy(tmp[count].name, iter.name, LTTNG_UST_SYM_NAME_LEN);
1398                         memcpy(tmp[count].loglevel, iter.loglevel, LTTNG_UST_SYM_NAME_LEN);
1399                         tmp[count].loglevel_value = iter.loglevel_value;
1400                         tmp[count].type = LTTNG_UST_TRACEPOINT;
1401                         tmp[count].pid = app->key.pid;
1402                         tmp[count].enabled = -1;
1403                         count++;
1404                 }
1405         }
1406
1407         ret = count;
1408         *events = tmp;
1409
1410         DBG2("UST app list events done (%zu events)", count);
1411
1412 rcu_error:
1413         rcu_read_unlock();
1414 error:
1415         return ret;
1416 }
1417
1418 /*
1419  * Free and clean all traceable apps of the global list.
1420  */
1421 void ust_app_clean_list(void)
1422 {
1423         int ret;
1424         struct cds_lfht_iter iter;
1425         struct ust_app *app;
1426
1427         DBG2("UST app cleaning registered apps hash table");
1428
1429         rcu_read_lock();
1430
1431         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
1432                 ret = hashtable_del(ust_app_ht, &iter);
1433                 assert(!ret);
1434                 call_rcu(&iter.node->head, delete_ust_app_rcu);
1435         }
1436
1437         hashtable_destroy(ust_app_ht);
1438         hashtable_destroy(ust_app_sock_key_map);
1439
1440         rcu_read_unlock();
1441 }
1442
1443 /*
1444  * Init UST app hash table.
1445  */
1446 void ust_app_ht_alloc(void)
1447 {
1448         ust_app_ht = hashtable_new(0);
1449         ust_app_sock_key_map = hashtable_new(0);
1450 }
1451
1452 /*
1453  * For a specific UST session, disable the channel for all registered apps.
1454  */
1455 int ust_app_disable_channel_glb(struct ltt_ust_session *usess,
1456                 struct ltt_ust_channel *uchan)
1457 {
1458         int ret = 0;
1459         struct cds_lfht_iter iter;
1460         struct cds_lfht_node *ua_chan_node;
1461         struct ust_app *app;
1462         struct ust_app_session *ua_sess;
1463         struct ust_app_channel *ua_chan;
1464
1465         if (usess == NULL || uchan == NULL) {
1466                 ERR("Disabling UST global channel with NULL values");
1467                 ret = -1;
1468                 goto error;
1469         }
1470
1471         DBG2("UST app disabling channel %s from global domain for session uid %d",
1472                         uchan->name, usess->uid);
1473
1474         rcu_read_lock();
1475
1476         /* For every registered applications */
1477         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
1478                 ua_sess = lookup_session_by_app(usess, app);
1479                 if (ua_sess == NULL) {
1480                         continue;
1481                 }
1482
1483                 /* Get channel */
1484                 ua_chan_node = hashtable_lookup(ua_sess->channels,
1485                                 (void *)uchan->name, strlen(uchan->name), &iter);
1486                 /* If the session if found for the app, the channel must be there */
1487                 assert(ua_chan_node);
1488
1489                 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
1490                 /* The channel must not be already disabled */
1491                 assert(ua_chan->enabled == 1);
1492
1493                 /* Disable channel onto application */
1494                 ret = disable_ust_app_channel(ua_sess, ua_chan, app);
1495                 if (ret < 0) {
1496                         /* XXX: We might want to report this error at some point... */
1497                         continue;
1498                 }
1499         }
1500
1501         rcu_read_unlock();
1502
1503 error:
1504         return ret;
1505 }
1506
1507 /*
1508  * For a specific UST session, enable the channel for all registered apps.
1509  */
1510 int ust_app_enable_channel_glb(struct ltt_ust_session *usess,
1511                 struct ltt_ust_channel *uchan)
1512 {
1513         int ret = 0;
1514         struct cds_lfht_iter iter;
1515         struct ust_app *app;
1516         struct ust_app_session *ua_sess;
1517
1518         if (usess == NULL || uchan == NULL) {
1519                 ERR("Adding UST global channel to NULL values");
1520                 ret = -1;
1521                 goto error;
1522         }
1523
1524         DBG2("UST app enabling channel %s to global domain for session uid %d",
1525                         uchan->name, usess->uid);
1526
1527         rcu_read_lock();
1528
1529         /* For every registered applications */
1530         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
1531                 ua_sess = lookup_session_by_app(usess, app);
1532                 if (ua_sess == NULL) {
1533                         continue;
1534                 }
1535
1536                 /* Enable channel onto application */
1537                 ret = enable_ust_app_channel(ua_sess, uchan, app);
1538                 if (ret < 0) {
1539                         /* XXX: We might want to report this error at some point... */
1540                         continue;
1541                 }
1542         }
1543
1544         rcu_read_unlock();
1545
1546 error:
1547         return ret;
1548 }
1549
1550 /*
1551  * Disable an event in a channel and for a specific session.
1552  */
1553 int ust_app_disable_event_glb(struct ltt_ust_session *usess,
1554                 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent)
1555 {
1556         int ret = 0;
1557         struct cds_lfht_iter iter, uiter;
1558         struct cds_lfht_node *ua_chan_node, *ua_event_node;
1559         struct ust_app *app;
1560         struct ust_app_session *ua_sess;
1561         struct ust_app_channel *ua_chan;
1562         struct ust_app_event *ua_event;
1563
1564         DBG("UST app disabling event %s for all apps in channel "
1565                         "%s for session uid %d", uevent->attr.name, uchan->name, usess->uid);
1566
1567         rcu_read_lock();
1568
1569         /* For all registered applications */
1570         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
1571                 ua_sess = lookup_session_by_app(usess, app);
1572                 if (ua_sess == NULL) {
1573                         /* Next app */
1574                         continue;
1575                 }
1576
1577                 /* Lookup channel in the ust app session */
1578                 ua_chan_node = hashtable_lookup(ua_sess->channels,
1579                                 (void *)uchan->name, strlen(uchan->name), &uiter);
1580                 if (ua_chan_node == NULL) {
1581                         DBG2("Channel %s not found in session uid %d for app pid %d."
1582                                         "Skipping", uchan->name, usess->uid, app->key.pid);
1583                         continue;
1584                 }
1585                 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
1586
1587                 ua_event_node = hashtable_lookup(ua_chan->events,
1588                                 (void *)uevent->attr.name, strlen(uevent->attr.name), &uiter);
1589                 if (ua_event_node == NULL) {
1590                         DBG2("Event %s not found in channel %s for app pid %d."
1591                                         "Skipping", uevent->attr.name, uchan->name, app->key.pid);
1592                         continue;
1593                 }
1594                 ua_event = caa_container_of(ua_event_node, struct ust_app_event, node);
1595
1596                 ret = disable_ust_app_event(ua_sess, ua_chan, ua_event, app);
1597                 if (ret < 0) {
1598                         /* XXX: Report error someday... */
1599                         continue;
1600                 }
1601         }
1602
1603         rcu_read_unlock();
1604
1605         return ret;
1606 }
1607
1608 /*
1609  * For a specific UST session and UST channel, the event for all
1610  * registered apps.
1611  */
1612 int ust_app_disable_all_event_glb(struct ltt_ust_session *usess,
1613                 struct ltt_ust_channel *uchan)
1614 {
1615         int ret = 0;
1616         struct cds_lfht_iter iter, uiter;
1617         struct cds_lfht_node *ua_chan_node;
1618         struct ust_app *app;
1619         struct ust_app_session *ua_sess;
1620         struct ust_app_channel *ua_chan;
1621         struct ust_app_event *ua_event;
1622
1623         DBG("UST app disabling all event for all apps in channel "
1624                         "%s for session uid %d", uchan->name, usess->uid);
1625
1626         rcu_read_lock();
1627
1628         /* For all registered applications */
1629         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
1630                 ua_sess = lookup_session_by_app(usess, app);
1631                 /* If ua_sess is NULL, there is a code flow error */
1632                 assert(ua_sess);
1633
1634                 /* Lookup channel in the ust app session */
1635                 ua_chan_node = hashtable_lookup(ua_sess->channels, (void *)uchan->name,
1636                                 strlen(uchan->name), &uiter);
1637                 /* If the channel is not found, there is a code flow error */
1638                 assert(ua_chan_node);
1639
1640                 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
1641
1642                 /* Disable each events of channel */
1643                 cds_lfht_for_each_entry(ua_chan->events, &uiter, ua_event, node) {
1644                         ret = disable_ust_app_event(ua_sess, ua_chan, ua_event, app);
1645                         if (ret < 0) {
1646                                 /* XXX: Report error someday... */
1647                                 continue;
1648                         }
1649                 }
1650         }
1651
1652         rcu_read_unlock();
1653
1654         return ret;
1655 }
1656
1657 /*
1658  * For a specific UST session, create the channel for all registered apps.
1659  */
1660 int ust_app_create_channel_glb(struct ltt_ust_session *usess,
1661                 struct ltt_ust_channel *uchan)
1662 {
1663         int ret = 0;
1664         struct cds_lfht_iter iter;
1665         struct ust_app *app;
1666         struct ust_app_session *ua_sess;
1667         struct ust_app_channel *ua_chan;
1668
1669         if (usess == NULL || uchan == NULL) {
1670                 ERR("Adding UST global channel to NULL values");
1671                 ret = -1;
1672                 goto error;
1673         }
1674
1675         DBG2("UST app adding channel %s to global domain for session uid %d",
1676                         uchan->name, usess->uid);
1677
1678         rcu_read_lock();
1679
1680         /* For every registered applications */
1681         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
1682                 /*
1683                  * Create session on the tracer side and add it to app session HT. Note
1684                  * that if session exist, it will simply return a pointer to the ust
1685                  * app session.
1686                  */
1687                 ua_sess = create_ust_app_session(usess, app);
1688                 if (ua_sess == NULL) {
1689                         continue;
1690                 }
1691
1692                 /* Create channel onto application */
1693                 ua_chan = create_ust_app_channel(ua_sess, uchan, app);
1694                 if (ua_chan == NULL) {
1695                         continue;
1696                 }
1697         }
1698
1699         rcu_read_unlock();
1700
1701 error:
1702         return ret;
1703 }
1704
1705 /*
1706  * Enable event for a specific session and channel on the tracer.
1707  */
1708 int ust_app_enable_event_glb(struct ltt_ust_session *usess,
1709                 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent)
1710 {
1711         int ret = 0;
1712         struct cds_lfht_iter iter, uiter;
1713         struct cds_lfht_node *ua_chan_node, *ua_event_node;
1714         struct ust_app *app;
1715         struct ust_app_session *ua_sess;
1716         struct ust_app_channel *ua_chan;
1717         struct ust_app_event *ua_event;
1718
1719         DBG("UST app enabling event %s for all apps for session uid %d",
1720                         uevent->attr.name, usess->uid);
1721
1722         /*
1723          * NOTE: At this point, this function is called only if the session and
1724          * channel passed are already created for all apps. and enabled on the
1725          * tracer also.
1726          */
1727
1728         rcu_read_lock();
1729
1730         /* For all registered applications */
1731         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
1732                 ua_sess = lookup_session_by_app(usess, app);
1733                 /* If ua_sess is NULL, there is a code flow error */
1734                 assert(ua_sess);
1735
1736                 /* Lookup channel in the ust app session */
1737                 ua_chan_node = hashtable_lookup(ua_sess->channels, (void *)uchan->name,
1738                                 strlen(uchan->name), &uiter);
1739                 /* If the channel is not found, there is a code flow error */
1740                 assert(ua_chan_node);
1741
1742                 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
1743
1744                 ua_event_node = hashtable_lookup(ua_sess->channels,
1745                                 (void*)uevent->attr.name, strlen(uevent->attr.name), &uiter);
1746                 if (ua_event_node == NULL) {
1747                         DBG3("UST app enable event %s not found. Skipping app",
1748                                         uevent->attr.name);
1749                         continue;
1750                 }
1751                 ua_event = caa_container_of(ua_event_node, struct ust_app_event, node);
1752
1753                 ret = enable_ust_app_event(ua_sess, ua_event, app);
1754                 if (ret < 0) {
1755                         /* XXX: Report error someday... */
1756                         continue;
1757                 }
1758         }
1759
1760         rcu_read_unlock();
1761
1762         return ret;
1763 }
1764
1765 /*
1766  * For a specific existing UST session and UST channel, creates the event for
1767  * all registered apps.
1768  */
1769 int ust_app_create_event_glb(struct ltt_ust_session *usess,
1770                 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent)
1771 {
1772         int ret = 0;
1773         struct cds_lfht_iter iter, uiter;
1774         struct cds_lfht_node *ua_chan_node;
1775         struct ust_app *app;
1776         struct ust_app_session *ua_sess;
1777         struct ust_app_channel *ua_chan;
1778
1779         DBG("UST app creating event %s for all apps for session uid %d",
1780                         uevent->attr.name, usess->uid);
1781
1782         /*
1783          * NOTE: At this point, this function is called only if the session and
1784          * channel passed are already created for all apps. and enabled on the
1785          * tracer also.
1786          */
1787
1788         rcu_read_lock();
1789
1790         /* For all registered applications */
1791         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
1792                 ua_sess = lookup_session_by_app(usess, app);
1793                 /* If ua_sess is NULL, there is a code flow error */
1794                 assert(ua_sess);
1795
1796                 /* Lookup channel in the ust app session */
1797                 ua_chan_node = hashtable_lookup(ua_sess->channels, (void *)uchan->name,
1798                                 strlen(uchan->name), &uiter);
1799                 /* If the channel is not found, there is a code flow error */
1800                 assert(ua_chan_node);
1801
1802                 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
1803
1804                 ret = create_ust_app_event(ua_sess, ua_chan, uevent, app);
1805                 if (ret < 0) {
1806                         continue;
1807                 }
1808         }
1809
1810         rcu_read_unlock();
1811
1812         return ret;
1813 }
1814
1815 /*
1816  * Start tracing for a specific UST session and app.
1817  */
1818 int ust_app_start_trace(struct ltt_ust_session *usess, struct ust_app *app)
1819 {
1820         int ret = 0;
1821         struct cds_lfht_iter iter;
1822         struct ust_app_session *ua_sess;
1823         struct ust_app_channel *ua_chan;
1824         struct ltt_ust_stream *ustream;
1825         int consumerd_fd;
1826
1827         DBG("Starting tracing for ust app pid %d", app->key.pid);
1828
1829         rcu_read_lock();
1830
1831         ua_sess = lookup_session_by_app(usess, app);
1832         if (ua_sess == NULL) {
1833                 goto error_rcu_unlock;
1834         }
1835
1836         /* Upon restart, we skip the setup, already done */
1837         if (ua_sess->started) {
1838                 goto skip_setup;
1839         }
1840
1841         ret = create_ust_app_metadata(ua_sess, usess->pathname, app);
1842         if (ret < 0) {
1843                 goto error_rcu_unlock;
1844         }
1845
1846         /* For each channel */
1847         cds_lfht_for_each_entry(ua_sess->channels, &iter, ua_chan, node) {
1848                 /* Create all streams */
1849                 while (1) {
1850                         /* Create UST stream */
1851                         ustream = zmalloc(sizeof(*ustream));
1852                         if (ustream == NULL) {
1853                                 PERROR("zmalloc ust stream");
1854                                 goto error_rcu_unlock;
1855                         }
1856
1857                         ret = ustctl_create_stream(app->key.sock, ua_chan->obj,
1858                                         &ustream->obj);
1859                         if (ret < 0) {
1860                                 /* Got all streams */
1861                                 break;
1862                         }
1863                         ustream->handle = ustream->obj->handle;
1864
1865                         /* Order is important */
1866                         cds_list_add_tail(&ustream->list, &ua_chan->streams.head);
1867                         ret = snprintf(ustream->pathname, PATH_MAX, "%s/%s_%u",
1868                                         ua_sess->path, ua_chan->name,
1869                                         ua_chan->streams.count++);
1870                         if (ret < 0) {
1871                                 PERROR("asprintf UST create stream");
1872                                 continue;
1873                         }
1874                         DBG2("UST stream %d ready at %s", ua_chan->streams.count,
1875                                         ustream->pathname);
1876                 }
1877         }
1878
1879         switch (app->bits_per_long) {
1880         case 64:
1881                 consumerd_fd = ust_consumerd64_fd;
1882                 break;
1883         case 32:
1884                 consumerd_fd = ust_consumerd32_fd;
1885                 break;
1886         default:
1887                 ret = -EINVAL;
1888                 goto error_rcu_unlock;
1889         }
1890
1891         /* Setup UST consumer socket and send fds to it */
1892         ret = ust_consumer_send_session(consumerd_fd, ua_sess);
1893         if (ret < 0) {
1894                 goto error_rcu_unlock;
1895         }
1896         ua_sess->started = 1;
1897
1898 skip_setup:
1899         /* This start the UST tracing */
1900         ret = ustctl_start_session(app->key.sock, ua_sess->handle);
1901         if (ret < 0) {
1902                 ERR("Error starting tracing for app pid: %d", app->key.pid);
1903                 goto error_rcu_unlock;
1904         }
1905
1906         rcu_read_unlock();
1907
1908         /* Quiescent wait after starting trace */
1909         ustctl_wait_quiescent(app->key.sock);
1910
1911         return 0;
1912
1913 error_rcu_unlock:
1914         rcu_read_unlock();
1915         return -1;
1916 }
1917
1918 /*
1919  * Stop tracing for a specific UST session and app.
1920  */
1921 int ust_app_stop_trace(struct ltt_ust_session *usess, struct ust_app *app)
1922 {
1923         int ret = 0;
1924         struct ust_app_session *ua_sess;
1925
1926         DBG("Stopping tracing for ust app pid %d", app->key.pid);
1927
1928         rcu_read_lock();
1929
1930         ua_sess = lookup_session_by_app(usess, app);
1931         if (ua_sess == NULL) {
1932                 /* Only malloc can failed so something is really wrong */
1933                 goto error_rcu_unlock;
1934         }
1935
1936 #if 0   /* only useful when periodical flush will be supported */
1937         /* need to keep a handle on shm in session for this. */
1938         /* Flush all buffers before stopping */
1939         ret = ustctl_flush_buffer(usess->sock, usess->metadata->obj);
1940         if (ret < 0) {
1941                 ERR("UST metadata flush failed");
1942         }
1943
1944         cds_list_for_each_entry(ustchan, &usess->channels.head, list) {
1945                 ret = ustctl_flush_buffer(usess->sock, ustchan->obj);
1946                 if (ret < 0) {
1947                         ERR("UST flush buffer error");
1948                 }
1949         }
1950 #endif
1951
1952         /* This inhibits UST tracing */
1953         ret = ustctl_stop_session(app->key.sock, ua_sess->handle);
1954         if (ret < 0) {
1955                 ERR("Error stopping tracing for app pid: %d", app->key.pid);
1956                 goto error_rcu_unlock;
1957         }
1958
1959         rcu_read_unlock();
1960
1961         /* Quiescent wait after stopping trace */
1962         ustctl_wait_quiescent(app->key.sock);
1963
1964         return 0;
1965
1966 error_rcu_unlock:
1967         rcu_read_unlock();
1968         return -1;
1969 }
1970
1971 /*
1972  * Destroy a specific UST session in apps.
1973  */
1974 int ust_app_destroy_trace(struct ltt_ust_session *usess, struct ust_app *app)
1975 {
1976         struct ust_app_session *ua_sess;
1977         struct lttng_ust_object_data obj;
1978         struct cds_lfht_iter iter;
1979         struct cds_lfht_node *node;
1980         int ret;
1981
1982         DBG("Destroy tracing for ust app pid %d", app->key.pid);
1983
1984         rcu_read_lock();
1985
1986         __lookup_session_by_app(usess, app, &iter);
1987         node = hashtable_iter_get_node(&iter);
1988         if (node == NULL) {
1989                 /* Only malloc can failed so something is really wrong */
1990                 goto error_rcu_unlock;
1991         }
1992         ua_sess = caa_container_of(node, struct ust_app_session, node);
1993         ret = hashtable_del(app->sessions, &iter);
1994         assert(!ret);
1995         delete_ust_app_session(app->key.sock, ua_sess);
1996         obj.handle = ua_sess->handle;
1997         obj.shm_fd = -1;
1998         obj.wait_fd = -1;
1999         obj.memory_map_size = 0;
2000         ustctl_release_object(app->key.sock, &obj);
2001
2002         rcu_read_unlock();
2003
2004         /* Quiescent wait after stopping trace */
2005         ustctl_wait_quiescent(app->key.sock);
2006
2007         return 0;
2008
2009 error_rcu_unlock:
2010         rcu_read_unlock();
2011         return -1;
2012 }
2013
2014 /*
2015  * Start tracing for the UST session.
2016  */
2017 int ust_app_start_trace_all(struct ltt_ust_session *usess)
2018 {
2019         int ret = 0;
2020         struct cds_lfht_iter iter;
2021         struct ust_app *app;
2022
2023         DBG("Starting all UST traces");
2024
2025         rcu_read_lock();
2026
2027         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
2028                 ret = ust_app_start_trace(usess, app);
2029                 if (ret < 0) {
2030                         /* Continue to next apps even on error */
2031                         continue;
2032                 }
2033         }
2034
2035         rcu_read_unlock();
2036
2037         return 0;
2038 }
2039
2040 /*
2041  * Start tracing for the UST session.
2042  */
2043 int ust_app_stop_trace_all(struct ltt_ust_session *usess)
2044 {
2045         int ret = 0;
2046         struct cds_lfht_iter iter;
2047         struct ust_app *app;
2048
2049         DBG("Stopping all UST traces");
2050
2051         rcu_read_lock();
2052
2053         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
2054                 ret = ust_app_stop_trace(usess, app);
2055                 if (ret < 0) {
2056                         /* Continue to next apps even on error */
2057                         continue;
2058                 }
2059         }
2060
2061         rcu_read_unlock();
2062
2063         return 0;
2064 }
2065
2066 /*
2067  * Destroy app UST session.
2068  */
2069 int ust_app_destroy_trace_all(struct ltt_ust_session *usess)
2070 {
2071         int ret = 0;
2072         struct cds_lfht_iter iter;
2073         struct ust_app *app;
2074
2075         DBG("Destroy all UST traces");
2076
2077         rcu_read_lock();
2078
2079         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
2080                 ret = ust_app_destroy_trace(usess, app);
2081                 if (ret < 0) {
2082                         /* Continue to next apps even on error */
2083                         continue;
2084                 }
2085         }
2086
2087         rcu_read_unlock();
2088
2089         return 0;
2090 }
2091
2092 /*
2093  * Add channels/events from UST global domain to registered apps at sock.
2094  */
2095 void ust_app_global_update(struct ltt_ust_session *usess, int sock)
2096 {
2097         int ret = 0;
2098         struct cds_lfht_iter iter;
2099         struct ust_app *app;
2100         struct ust_app_session *ua_sess;
2101         struct ust_app_channel *ua_chan;
2102         struct ust_app_event *ua_event;
2103
2104         if (usess == NULL) {
2105                 ERR("No UST session on global update. Returning");
2106                 goto error;
2107         }
2108
2109         DBG2("UST app global update for app sock %d for session uid %d", sock,
2110                         usess->uid);
2111
2112         rcu_read_lock();
2113
2114         app = find_app_by_sock(sock);
2115         if (app == NULL) {
2116                 ERR("Failed to update app sock %d", sock);
2117                 goto error;
2118         }
2119
2120         ua_sess = create_ust_app_session(usess, app);
2121         if (ua_sess == NULL) {
2122                 goto error;
2123         }
2124
2125         /*
2126          * We can iterate safely here over all UST app session sicne the create ust
2127          * app session above made a shadow copy of the UST global domain from the
2128          * ltt ust session.
2129          */
2130         cds_lfht_for_each_entry(ua_sess->channels, &iter, ua_chan, node) {
2131                 ret = create_ust_channel(app, ua_sess, ua_chan);
2132                 if (ret < 0) {
2133                         /* FIXME: Should we quit here or continue... */
2134                         continue;
2135                 }
2136
2137                 /* For each events */
2138                 cds_lfht_for_each_entry(ua_chan->events, &iter, ua_event, node) {
2139                         ret = create_ust_event(app, ua_sess, ua_chan, ua_event);
2140                         if (ret < 0) {
2141                                 /* FIXME: Should we quit here or continue... */
2142                                 continue;
2143                         }
2144                 }
2145         }
2146
2147         if (usess->start_trace) {
2148                 ret = ust_app_start_trace(usess, app);
2149                 if (ret < 0) {
2150                         goto error;
2151                 }
2152
2153                 DBG2("UST trace started for app pid %d", app->key.pid);
2154         }
2155
2156 error:
2157         rcu_read_unlock();
2158         return;
2159 }
2160
2161 /*
2162  * Add context to a specific channel for global UST domain.
2163  */
2164 int ust_app_add_ctx_channel_glb(struct ltt_ust_session *usess,
2165                 struct ltt_ust_channel *uchan, struct ltt_ust_context *uctx)
2166 {
2167         int ret = 0;
2168         struct cds_lfht_node *ua_chan_node;
2169         struct cds_lfht_iter iter, uiter;
2170         struct ust_app_channel *ua_chan = NULL;
2171         struct ust_app_session *ua_sess;
2172         struct ust_app *app;
2173
2174         rcu_read_lock();
2175
2176         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
2177                 ua_sess = lookup_session_by_app(usess, app);
2178                 if (ua_sess == NULL) {
2179                         continue;
2180                 }
2181
2182                 /* Lookup channel in the ust app session */
2183                 ua_chan_node = hashtable_lookup(ua_sess->channels,
2184                                 (void *)uchan->name, strlen(uchan->name), &uiter);
2185                 if (ua_chan_node == NULL) {
2186                         continue;
2187                 }
2188                 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel,
2189                                 node);
2190
2191                 ret = create_ust_app_channel_context(ua_sess, ua_chan, &uctx->ctx, app);
2192                 if (ret < 0) {
2193                         continue;
2194                 }
2195         }
2196
2197         /* Add ltt UST context node to ltt UST channel */
2198         hashtable_add_unique(uchan->ctx, &uctx->node);
2199
2200         rcu_read_unlock();
2201         return ret;
2202 }
2203
2204 /*
2205  * Add context to a specific event in a channel for global UST domain.
2206  */
2207 int ust_app_add_ctx_event_glb(struct ltt_ust_session *usess,
2208                 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent,
2209                 struct ltt_ust_context *uctx)
2210 {
2211         int ret = 0;
2212         struct cds_lfht_node *ua_chan_node, *ua_event_node;
2213         struct cds_lfht_iter iter, uiter;
2214         struct ust_app_session *ua_sess;
2215         struct ust_app_event *ua_event;
2216         struct ust_app_channel *ua_chan = NULL;
2217         struct ust_app *app;
2218
2219         rcu_read_lock();
2220
2221         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
2222                 ua_sess = lookup_session_by_app(usess, app);
2223                 if (ua_sess == NULL) {
2224                         continue;
2225                 }
2226
2227                 /* Lookup channel in the ust app session */
2228                 ua_chan_node = hashtable_lookup(ua_sess->channels,
2229                                 (void *)uchan->name, strlen(uchan->name), &uiter);
2230                 if (ua_chan_node == NULL) {
2231                         continue;
2232                 }
2233                 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel,
2234                                 node);
2235
2236                 ua_event_node = hashtable_lookup(ua_chan->events,
2237                                 (void *)uevent->attr.name, strlen(uevent->attr.name), &uiter);
2238                 if (ua_event_node == NULL) {
2239                         continue;
2240                 }
2241                 ua_event = caa_container_of(ua_event_node, struct ust_app_event,
2242                                 node);
2243
2244                 ret = create_ust_app_event_context(ua_sess, ua_event, &uctx->ctx, app);
2245                 if (ret < 0) {
2246                         continue;
2247                 }
2248         }
2249
2250         /* Add ltt UST context node to ltt UST event */
2251         hashtable_add_unique(uevent->ctx, &uctx->node);
2252
2253         rcu_read_unlock();
2254         return ret;
2255 }
2256
2257 /*
2258  * Enable event for a channel from a UST session for a specific PID.
2259  */
2260 int ust_app_enable_event_pid(struct ltt_ust_session *usess,
2261                 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent, pid_t pid)
2262 {
2263         int ret = 0;
2264         struct cds_lfht_iter iter;
2265         struct cds_lfht_node *ua_chan_node, *ua_event_node;
2266         struct ust_app *app;
2267         struct ust_app_session *ua_sess;
2268         struct ust_app_channel *ua_chan;
2269         struct ust_app_event *ua_event;
2270
2271         DBG("UST app enabling event %s for PID %d", uevent->attr.name, pid);
2272
2273         rcu_read_lock();
2274
2275         app = ust_app_find_by_pid(pid);
2276         if (app == NULL) {
2277                 ERR("UST app enable event per PID %d not found", pid);
2278                 ret = -1;
2279                 goto error;
2280         }
2281
2282         ua_sess = lookup_session_by_app(usess, app);
2283         /* If ua_sess is NULL, there is a code flow error */
2284         assert(ua_sess);
2285
2286         /* Lookup channel in the ust app session */
2287         ua_chan_node = hashtable_lookup(ua_sess->channels, (void *)uchan->name,
2288                         strlen(uchan->name), &iter);
2289         /* If the channel is not found, there is a code flow error */
2290         assert(ua_chan_node);
2291
2292         ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
2293
2294         ua_event_node = hashtable_lookup(ua_sess->channels,
2295                         (void*)uevent->attr.name, strlen(uevent->attr.name), &iter);
2296         if (ua_event_node == NULL) {
2297                 ret = create_ust_app_event(ua_sess, ua_chan, uevent, app);
2298                 if (ret < 0) {
2299                         goto error;
2300                 }
2301         } else {
2302                 ua_event = caa_container_of(ua_event_node, struct ust_app_event, node);
2303
2304                 ret = enable_ust_app_event(ua_sess, ua_event, app);
2305                 if (ret < 0) {
2306                         goto error;
2307                 }
2308         }
2309
2310 error:
2311         rcu_read_unlock();
2312         return ret;
2313 }