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                 handle = ustctl_tracepoint_list(app->key.sock);
1376                 if (handle < 0) {
1377                         ERR("UST app list events getting handle failed for app pid %d",
1378                                         app->key.pid);
1379                         continue;
1380                 }
1381
1382                 while ((ret = ustctl_tracepoint_list_get(app->key.sock, handle,
1383                                                 tmp[count].name)) != -ENOENT) {
1384                         if (count > nbmem) {
1385                                 DBG2("Reallocating event list from %zu to %zu bytes", nbmem,
1386                                                 nbmem + UST_APP_EVENT_LIST_SIZE);
1387                                 nbmem += UST_APP_EVENT_LIST_SIZE;
1388                                 tmp = realloc(tmp, nbmem * sizeof(struct lttng_event));
1389                                 if (tmp == NULL) {
1390                                         PERROR("realloc ust app events");
1391                                         ret = -ENOMEM;
1392                                         goto rcu_error;
1393                                 }
1394                         }
1395
1396                         tmp[count].type = LTTNG_UST_TRACEPOINT;
1397                         tmp[count].pid = app->key.pid;
1398                         tmp[count].enabled = -1;
1399                         count++;
1400                 }
1401         }
1402
1403         ret = count;
1404         *events = tmp;
1405
1406         DBG2("UST app list events done (%zu events)", count);
1407
1408 rcu_error:
1409         rcu_read_unlock();
1410 error:
1411         return ret;
1412 }
1413
1414 /*
1415  * Free and clean all traceable apps of the global list.
1416  */
1417 void ust_app_clean_list(void)
1418 {
1419         int ret;
1420         struct cds_lfht_iter iter;
1421         struct ust_app *app;
1422
1423         DBG2("UST app cleaning registered apps hash table");
1424
1425         rcu_read_lock();
1426
1427         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
1428                 ret = hashtable_del(ust_app_ht, &iter);
1429                 assert(!ret);
1430                 call_rcu(&iter.node->head, delete_ust_app_rcu);
1431         }
1432
1433         hashtable_destroy(ust_app_ht);
1434         hashtable_destroy(ust_app_sock_key_map);
1435
1436         rcu_read_unlock();
1437 }
1438
1439 /*
1440  * Init UST app hash table.
1441  */
1442 void ust_app_ht_alloc(void)
1443 {
1444         ust_app_ht = hashtable_new(0);
1445         ust_app_sock_key_map = hashtable_new(0);
1446 }
1447
1448 /*
1449  * For a specific UST session, disable the channel for all registered apps.
1450  */
1451 int ust_app_disable_channel_glb(struct ltt_ust_session *usess,
1452                 struct ltt_ust_channel *uchan)
1453 {
1454         int ret = 0;
1455         struct cds_lfht_iter iter;
1456         struct cds_lfht_node *ua_chan_node;
1457         struct ust_app *app;
1458         struct ust_app_session *ua_sess;
1459         struct ust_app_channel *ua_chan;
1460
1461         if (usess == NULL || uchan == NULL) {
1462                 ERR("Disabling UST global channel with NULL values");
1463                 ret = -1;
1464                 goto error;
1465         }
1466
1467         DBG2("UST app disabling channel %s from global domain for session uid %d",
1468                         uchan->name, usess->uid);
1469
1470         rcu_read_lock();
1471
1472         /* For every registered applications */
1473         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
1474                 ua_sess = lookup_session_by_app(usess, app);
1475                 if (ua_sess == NULL) {
1476                         continue;
1477                 }
1478
1479                 /* Get channel */
1480                 ua_chan_node = hashtable_lookup(ua_sess->channels,
1481                                 (void *)uchan->name, strlen(uchan->name), &iter);
1482                 /* If the session if found for the app, the channel must be there */
1483                 assert(ua_chan_node);
1484
1485                 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
1486                 /* The channel must not be already disabled */
1487                 assert(ua_chan->enabled == 1);
1488
1489                 /* Disable channel onto application */
1490                 ret = disable_ust_app_channel(ua_sess, ua_chan, app);
1491                 if (ret < 0) {
1492                         /* XXX: We might want to report this error at some point... */
1493                         continue;
1494                 }
1495         }
1496
1497         rcu_read_unlock();
1498
1499 error:
1500         return ret;
1501 }
1502
1503 /*
1504  * For a specific UST session, enable the channel for all registered apps.
1505  */
1506 int ust_app_enable_channel_glb(struct ltt_ust_session *usess,
1507                 struct ltt_ust_channel *uchan)
1508 {
1509         int ret = 0;
1510         struct cds_lfht_iter iter;
1511         struct ust_app *app;
1512         struct ust_app_session *ua_sess;
1513
1514         if (usess == NULL || uchan == NULL) {
1515                 ERR("Adding UST global channel to NULL values");
1516                 ret = -1;
1517                 goto error;
1518         }
1519
1520         DBG2("UST app enabling channel %s to global domain for session uid %d",
1521                         uchan->name, usess->uid);
1522
1523         rcu_read_lock();
1524
1525         /* For every registered applications */
1526         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
1527                 ua_sess = lookup_session_by_app(usess, app);
1528                 if (ua_sess == NULL) {
1529                         continue;
1530                 }
1531
1532                 /* Enable channel onto application */
1533                 ret = enable_ust_app_channel(ua_sess, uchan, app);
1534                 if (ret < 0) {
1535                         /* XXX: We might want to report this error at some point... */
1536                         continue;
1537                 }
1538         }
1539
1540         rcu_read_unlock();
1541
1542 error:
1543         return ret;
1544 }
1545
1546 /*
1547  * Disable an event in a channel and for a specific session.
1548  */
1549 int ust_app_disable_event_glb(struct ltt_ust_session *usess,
1550                 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent)
1551 {
1552         int ret = 0;
1553         struct cds_lfht_iter iter, uiter;
1554         struct cds_lfht_node *ua_chan_node, *ua_event_node;
1555         struct ust_app *app;
1556         struct ust_app_session *ua_sess;
1557         struct ust_app_channel *ua_chan;
1558         struct ust_app_event *ua_event;
1559
1560         DBG("UST app disabling event %s for all apps in channel "
1561                         "%s for session uid %d", uevent->attr.name, uchan->name, usess->uid);
1562
1563         rcu_read_lock();
1564
1565         /* For all registered applications */
1566         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
1567                 ua_sess = lookup_session_by_app(usess, app);
1568                 if (ua_sess == NULL) {
1569                         /* Next app */
1570                         continue;
1571                 }
1572
1573                 /* Lookup channel in the ust app session */
1574                 ua_chan_node = hashtable_lookup(ua_sess->channels,
1575                                 (void *)uchan->name, strlen(uchan->name), &uiter);
1576                 if (ua_chan_node == NULL) {
1577                         DBG2("Channel %s not found in session uid %d for app pid %d."
1578                                         "Skipping", uchan->name, usess->uid, app->key.pid);
1579                         continue;
1580                 }
1581                 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
1582
1583                 ua_event_node = hashtable_lookup(ua_chan->events,
1584                                 (void *)uevent->attr.name, strlen(uevent->attr.name), &uiter);
1585                 if (ua_event_node == NULL) {
1586                         DBG2("Event %s not found in channel %s for app pid %d."
1587                                         "Skipping", uevent->attr.name, uchan->name, app->key.pid);
1588                         continue;
1589                 }
1590                 ua_event = caa_container_of(ua_event_node, struct ust_app_event, node);
1591
1592                 ret = disable_ust_app_event(ua_sess, ua_chan, ua_event, app);
1593                 if (ret < 0) {
1594                         /* XXX: Report error someday... */
1595                         continue;
1596                 }
1597         }
1598
1599         rcu_read_unlock();
1600
1601         return ret;
1602 }
1603
1604 /*
1605  * For a specific UST session and UST channel, the event for all
1606  * registered apps.
1607  */
1608 int ust_app_disable_all_event_glb(struct ltt_ust_session *usess,
1609                 struct ltt_ust_channel *uchan)
1610 {
1611         int ret = 0;
1612         struct cds_lfht_iter iter, uiter;
1613         struct cds_lfht_node *ua_chan_node;
1614         struct ust_app *app;
1615         struct ust_app_session *ua_sess;
1616         struct ust_app_channel *ua_chan;
1617         struct ust_app_event *ua_event;
1618
1619         DBG("UST app disabling all event for all apps in channel "
1620                         "%s for session uid %d", uchan->name, usess->uid);
1621
1622         rcu_read_lock();
1623
1624         /* For all registered applications */
1625         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
1626                 ua_sess = lookup_session_by_app(usess, app);
1627                 /* If ua_sess is NULL, there is a code flow error */
1628                 assert(ua_sess);
1629
1630                 /* Lookup channel in the ust app session */
1631                 ua_chan_node = hashtable_lookup(ua_sess->channels, (void *)uchan->name,
1632                                 strlen(uchan->name), &uiter);
1633                 /* If the channel is not found, there is a code flow error */
1634                 assert(ua_chan_node);
1635
1636                 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
1637
1638                 /* Disable each events of channel */
1639                 cds_lfht_for_each_entry(ua_chan->events, &uiter, ua_event, node) {
1640                         ret = disable_ust_app_event(ua_sess, ua_chan, ua_event, app);
1641                         if (ret < 0) {
1642                                 /* XXX: Report error someday... */
1643                                 continue;
1644                         }
1645                 }
1646         }
1647
1648         rcu_read_unlock();
1649
1650         return ret;
1651 }
1652
1653 /*
1654  * For a specific UST session, create the channel for all registered apps.
1655  */
1656 int ust_app_create_channel_glb(struct ltt_ust_session *usess,
1657                 struct ltt_ust_channel *uchan)
1658 {
1659         int ret = 0;
1660         struct cds_lfht_iter iter;
1661         struct ust_app *app;
1662         struct ust_app_session *ua_sess;
1663         struct ust_app_channel *ua_chan;
1664
1665         if (usess == NULL || uchan == NULL) {
1666                 ERR("Adding UST global channel to NULL values");
1667                 ret = -1;
1668                 goto error;
1669         }
1670
1671         DBG2("UST app adding channel %s to global domain for session uid %d",
1672                         uchan->name, usess->uid);
1673
1674         rcu_read_lock();
1675
1676         /* For every registered applications */
1677         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
1678                 /*
1679                  * Create session on the tracer side and add it to app session HT. Note
1680                  * that if session exist, it will simply return a pointer to the ust
1681                  * app session.
1682                  */
1683                 ua_sess = create_ust_app_session(usess, app);
1684                 if (ua_sess == NULL) {
1685                         continue;
1686                 }
1687
1688                 /* Create channel onto application */
1689                 ua_chan = create_ust_app_channel(ua_sess, uchan, app);
1690                 if (ua_chan == NULL) {
1691                         continue;
1692                 }
1693         }
1694
1695         rcu_read_unlock();
1696
1697 error:
1698         return ret;
1699 }
1700
1701 /*
1702  * Enable event for a specific session and channel on the tracer.
1703  */
1704 int ust_app_enable_event_glb(struct ltt_ust_session *usess,
1705                 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent)
1706 {
1707         int ret = 0;
1708         struct cds_lfht_iter iter, uiter;
1709         struct cds_lfht_node *ua_chan_node, *ua_event_node;
1710         struct ust_app *app;
1711         struct ust_app_session *ua_sess;
1712         struct ust_app_channel *ua_chan;
1713         struct ust_app_event *ua_event;
1714
1715         DBG("UST app enabling event %s for all apps for session uid %d",
1716                         uevent->attr.name, usess->uid);
1717
1718         /*
1719          * NOTE: At this point, this function is called only if the session and
1720          * channel passed are already created for all apps. and enabled on the
1721          * tracer also.
1722          */
1723
1724         rcu_read_lock();
1725
1726         /* For all registered applications */
1727         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
1728                 ua_sess = lookup_session_by_app(usess, app);
1729                 /* If ua_sess is NULL, there is a code flow error */
1730                 assert(ua_sess);
1731
1732                 /* Lookup channel in the ust app session */
1733                 ua_chan_node = hashtable_lookup(ua_sess->channels, (void *)uchan->name,
1734                                 strlen(uchan->name), &uiter);
1735                 /* If the channel is not found, there is a code flow error */
1736                 assert(ua_chan_node);
1737
1738                 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
1739
1740                 ua_event_node = hashtable_lookup(ua_sess->channels,
1741                                 (void*)uevent->attr.name, strlen(uevent->attr.name), &uiter);
1742                 if (ua_event_node == NULL) {
1743                         DBG3("UST app enable event %s not found. Skipping app",
1744                                         uevent->attr.name);
1745                         continue;
1746                 }
1747                 ua_event = caa_container_of(ua_event_node, struct ust_app_event, node);
1748
1749                 ret = enable_ust_app_event(ua_sess, ua_event, app);
1750                 if (ret < 0) {
1751                         /* XXX: Report error someday... */
1752                         continue;
1753                 }
1754         }
1755
1756         rcu_read_unlock();
1757
1758         return ret;
1759 }
1760
1761 /*
1762  * For a specific existing UST session and UST channel, creates the event for
1763  * all registered apps.
1764  */
1765 int ust_app_create_event_glb(struct ltt_ust_session *usess,
1766                 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent)
1767 {
1768         int ret = 0;
1769         struct cds_lfht_iter iter, uiter;
1770         struct cds_lfht_node *ua_chan_node;
1771         struct ust_app *app;
1772         struct ust_app_session *ua_sess;
1773         struct ust_app_channel *ua_chan;
1774
1775         DBG("UST app creating event %s for all apps for session uid %d",
1776                         uevent->attr.name, usess->uid);
1777
1778         /*
1779          * NOTE: At this point, this function is called only if the session and
1780          * channel passed are already created for all apps. and enabled on the
1781          * tracer also.
1782          */
1783
1784         rcu_read_lock();
1785
1786         /* For all registered applications */
1787         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
1788                 ua_sess = lookup_session_by_app(usess, app);
1789                 /* If ua_sess is NULL, there is a code flow error */
1790                 assert(ua_sess);
1791
1792                 /* Lookup channel in the ust app session */
1793                 ua_chan_node = hashtable_lookup(ua_sess->channels, (void *)uchan->name,
1794                                 strlen(uchan->name), &uiter);
1795                 /* If the channel is not found, there is a code flow error */
1796                 assert(ua_chan_node);
1797
1798                 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
1799
1800                 ret = create_ust_app_event(ua_sess, ua_chan, uevent, app);
1801                 if (ret < 0) {
1802                         continue;
1803                 }
1804         }
1805
1806         rcu_read_unlock();
1807
1808         return ret;
1809 }
1810
1811 /*
1812  * Start tracing for a specific UST session and app.
1813  */
1814 int ust_app_start_trace(struct ltt_ust_session *usess, struct ust_app *app)
1815 {
1816         int ret = 0;
1817         struct cds_lfht_iter iter;
1818         struct ust_app_session *ua_sess;
1819         struct ust_app_channel *ua_chan;
1820         struct ltt_ust_stream *ustream;
1821         int consumerd_fd;
1822
1823         DBG("Starting tracing for ust app pid %d", app->key.pid);
1824
1825         rcu_read_lock();
1826
1827         ua_sess = lookup_session_by_app(usess, app);
1828         if (ua_sess == NULL) {
1829                 goto error_rcu_unlock;
1830         }
1831
1832         /* Upon restart, we skip the setup, already done */
1833         if (ua_sess->started) {
1834                 goto skip_setup;
1835         }
1836
1837         ret = create_ust_app_metadata(ua_sess, usess->pathname, app);
1838         if (ret < 0) {
1839                 goto error_rcu_unlock;
1840         }
1841
1842         /* For each channel */
1843         cds_lfht_for_each_entry(ua_sess->channels, &iter, ua_chan, node) {
1844                 /* Create all streams */
1845                 while (1) {
1846                         /* Create UST stream */
1847                         ustream = zmalloc(sizeof(*ustream));
1848                         if (ustream == NULL) {
1849                                 PERROR("zmalloc ust stream");
1850                                 goto error_rcu_unlock;
1851                         }
1852
1853                         ret = ustctl_create_stream(app->key.sock, ua_chan->obj,
1854                                         &ustream->obj);
1855                         if (ret < 0) {
1856                                 /* Got all streams */
1857                                 break;
1858                         }
1859                         ustream->handle = ustream->obj->handle;
1860
1861                         /* Order is important */
1862                         cds_list_add_tail(&ustream->list, &ua_chan->streams.head);
1863                         ret = snprintf(ustream->pathname, PATH_MAX, "%s/%s_%u",
1864                                         ua_sess->path, ua_chan->name,
1865                                         ua_chan->streams.count++);
1866                         if (ret < 0) {
1867                                 PERROR("asprintf UST create stream");
1868                                 continue;
1869                         }
1870                         DBG2("UST stream %d ready at %s", ua_chan->streams.count,
1871                                         ustream->pathname);
1872                 }
1873         }
1874
1875         switch (app->bits_per_long) {
1876         case 64:
1877                 consumerd_fd = ust_consumerd64_fd;
1878                 break;
1879         case 32:
1880                 consumerd_fd = ust_consumerd32_fd;
1881                 break;
1882         default:
1883                 ret = -EINVAL;
1884                 goto error_rcu_unlock;
1885         }
1886
1887         /* Setup UST consumer socket and send fds to it */
1888         ret = ust_consumer_send_session(consumerd_fd, ua_sess);
1889         if (ret < 0) {
1890                 goto error_rcu_unlock;
1891         }
1892         ua_sess->started = 1;
1893
1894 skip_setup:
1895         /* This start the UST tracing */
1896         ret = ustctl_start_session(app->key.sock, ua_sess->handle);
1897         if (ret < 0) {
1898                 ERR("Error starting tracing for app pid: %d", app->key.pid);
1899                 goto error_rcu_unlock;
1900         }
1901
1902         rcu_read_unlock();
1903
1904         /* Quiescent wait after starting trace */
1905         ustctl_wait_quiescent(app->key.sock);
1906
1907         return 0;
1908
1909 error_rcu_unlock:
1910         rcu_read_unlock();
1911         return -1;
1912 }
1913
1914 /*
1915  * Stop tracing for a specific UST session and app.
1916  */
1917 int ust_app_stop_trace(struct ltt_ust_session *usess, struct ust_app *app)
1918 {
1919         int ret = 0;
1920         struct ust_app_session *ua_sess;
1921
1922         DBG("Stopping tracing for ust app pid %d", app->key.pid);
1923
1924         rcu_read_lock();
1925
1926         ua_sess = lookup_session_by_app(usess, app);
1927         if (ua_sess == NULL) {
1928                 /* Only malloc can failed so something is really wrong */
1929                 goto error_rcu_unlock;
1930         }
1931
1932 #if 0   /* only useful when periodical flush will be supported */
1933         /* need to keep a handle on shm in session for this. */
1934         /* Flush all buffers before stopping */
1935         ret = ustctl_flush_buffer(usess->sock, usess->metadata->obj);
1936         if (ret < 0) {
1937                 ERR("UST metadata flush failed");
1938         }
1939
1940         cds_list_for_each_entry(ustchan, &usess->channels.head, list) {
1941                 ret = ustctl_flush_buffer(usess->sock, ustchan->obj);
1942                 if (ret < 0) {
1943                         ERR("UST flush buffer error");
1944                 }
1945         }
1946 #endif
1947
1948         /* This inhibits UST tracing */
1949         ret = ustctl_stop_session(app->key.sock, ua_sess->handle);
1950         if (ret < 0) {
1951                 ERR("Error stopping tracing for app pid: %d", app->key.pid);
1952                 goto error_rcu_unlock;
1953         }
1954
1955         rcu_read_unlock();
1956
1957         /* Quiescent wait after stopping trace */
1958         ustctl_wait_quiescent(app->key.sock);
1959
1960         return 0;
1961
1962 error_rcu_unlock:
1963         rcu_read_unlock();
1964         return -1;
1965 }
1966
1967 /*
1968  * Destroy a specific UST session in apps.
1969  */
1970 int ust_app_destroy_trace(struct ltt_ust_session *usess, struct ust_app *app)
1971 {
1972         struct ust_app_session *ua_sess;
1973         struct lttng_ust_object_data obj;
1974         struct cds_lfht_iter iter;
1975         struct cds_lfht_node *node;
1976         int ret;
1977
1978         DBG("Destroy tracing for ust app pid %d", app->key.pid);
1979
1980         rcu_read_lock();
1981
1982         __lookup_session_by_app(usess, app, &iter);
1983         node = hashtable_iter_get_node(&iter);
1984         if (node == NULL) {
1985                 /* Only malloc can failed so something is really wrong */
1986                 goto error_rcu_unlock;
1987         }
1988         ua_sess = caa_container_of(node, struct ust_app_session, node);
1989         ret = hashtable_del(app->sessions, &iter);
1990         assert(!ret);
1991         delete_ust_app_session(app->key.sock, ua_sess);
1992         obj.handle = ua_sess->handle;
1993         obj.shm_fd = -1;
1994         obj.wait_fd = -1;
1995         obj.memory_map_size = 0;
1996         ustctl_release_object(app->key.sock, &obj);
1997
1998         rcu_read_unlock();
1999
2000         /* Quiescent wait after stopping trace */
2001         ustctl_wait_quiescent(app->key.sock);
2002
2003         return 0;
2004
2005 error_rcu_unlock:
2006         rcu_read_unlock();
2007         return -1;
2008 }
2009
2010 /*
2011  * Start tracing for the UST session.
2012  */
2013 int ust_app_start_trace_all(struct ltt_ust_session *usess)
2014 {
2015         int ret = 0;
2016         struct cds_lfht_iter iter;
2017         struct ust_app *app;
2018
2019         DBG("Starting all UST traces");
2020
2021         rcu_read_lock();
2022
2023         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
2024                 ret = ust_app_start_trace(usess, app);
2025                 if (ret < 0) {
2026                         /* Continue to next apps even on error */
2027                         continue;
2028                 }
2029         }
2030
2031         rcu_read_unlock();
2032
2033         return 0;
2034 }
2035
2036 /*
2037  * Start tracing for the UST session.
2038  */
2039 int ust_app_stop_trace_all(struct ltt_ust_session *usess)
2040 {
2041         int ret = 0;
2042         struct cds_lfht_iter iter;
2043         struct ust_app *app;
2044
2045         DBG("Stopping all UST traces");
2046
2047         rcu_read_lock();
2048
2049         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
2050                 ret = ust_app_stop_trace(usess, app);
2051                 if (ret < 0) {
2052                         /* Continue to next apps even on error */
2053                         continue;
2054                 }
2055         }
2056
2057         rcu_read_unlock();
2058
2059         return 0;
2060 }
2061
2062 /*
2063  * Destroy app UST session.
2064  */
2065 int ust_app_destroy_trace_all(struct ltt_ust_session *usess)
2066 {
2067         int ret = 0;
2068         struct cds_lfht_iter iter;
2069         struct ust_app *app;
2070
2071         DBG("Destroy all UST traces");
2072
2073         rcu_read_lock();
2074
2075         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
2076                 ret = ust_app_destroy_trace(usess, app);
2077                 if (ret < 0) {
2078                         /* Continue to next apps even on error */
2079                         continue;
2080                 }
2081         }
2082
2083         rcu_read_unlock();
2084
2085         return 0;
2086 }
2087
2088 /*
2089  * Add channels/events from UST global domain to registered apps at sock.
2090  */
2091 void ust_app_global_update(struct ltt_ust_session *usess, int sock)
2092 {
2093         int ret = 0;
2094         struct cds_lfht_iter iter;
2095         struct ust_app *app;
2096         struct ust_app_session *ua_sess;
2097         struct ust_app_channel *ua_chan;
2098         struct ust_app_event *ua_event;
2099
2100         if (usess == NULL) {
2101                 ERR("No UST session on global update. Returning");
2102                 goto error;
2103         }
2104
2105         DBG2("UST app global update for app sock %d for session uid %d", sock,
2106                         usess->uid);
2107
2108         rcu_read_lock();
2109
2110         app = find_app_by_sock(sock);
2111         if (app == NULL) {
2112                 ERR("Failed to update app sock %d", sock);
2113                 goto error;
2114         }
2115
2116         ua_sess = create_ust_app_session(usess, app);
2117         if (ua_sess == NULL) {
2118                 goto error;
2119         }
2120
2121         /*
2122          * We can iterate safely here over all UST app session sicne the create ust
2123          * app session above made a shadow copy of the UST global domain from the
2124          * ltt ust session.
2125          */
2126         cds_lfht_for_each_entry(ua_sess->channels, &iter, ua_chan, node) {
2127                 ret = create_ust_channel(app, ua_sess, ua_chan);
2128                 if (ret < 0) {
2129                         /* FIXME: Should we quit here or continue... */
2130                         continue;
2131                 }
2132
2133                 /* For each events */
2134                 cds_lfht_for_each_entry(ua_chan->events, &iter, ua_event, node) {
2135                         ret = create_ust_event(app, ua_sess, ua_chan, ua_event);
2136                         if (ret < 0) {
2137                                 /* FIXME: Should we quit here or continue... */
2138                                 continue;
2139                         }
2140                 }
2141         }
2142
2143         if (usess->start_trace) {
2144                 ret = ust_app_start_trace(usess, app);
2145                 if (ret < 0) {
2146                         goto error;
2147                 }
2148
2149                 DBG2("UST trace started for app pid %d", app->key.pid);
2150         }
2151
2152 error:
2153         rcu_read_unlock();
2154         return;
2155 }
2156
2157 /*
2158  * Add context to a specific channel for global UST domain.
2159  */
2160 int ust_app_add_ctx_channel_glb(struct ltt_ust_session *usess,
2161                 struct ltt_ust_channel *uchan, struct ltt_ust_context *uctx)
2162 {
2163         int ret = 0;
2164         struct cds_lfht_node *ua_chan_node;
2165         struct cds_lfht_iter iter, uiter;
2166         struct ust_app_channel *ua_chan = NULL;
2167         struct ust_app_session *ua_sess;
2168         struct ust_app *app;
2169
2170         rcu_read_lock();
2171
2172         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
2173                 ua_sess = lookup_session_by_app(usess, app);
2174                 if (ua_sess == NULL) {
2175                         continue;
2176                 }
2177
2178                 /* Lookup channel in the ust app session */
2179                 ua_chan_node = hashtable_lookup(ua_sess->channels,
2180                                 (void *)uchan->name, strlen(uchan->name), &uiter);
2181                 if (ua_chan_node == NULL) {
2182                         continue;
2183                 }
2184                 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel,
2185                                 node);
2186
2187                 ret = create_ust_app_channel_context(ua_sess, ua_chan, &uctx->ctx, app);
2188                 if (ret < 0) {
2189                         continue;
2190                 }
2191         }
2192
2193         /* Add ltt UST context node to ltt UST channel */
2194         hashtable_add_unique(uchan->ctx, &uctx->node);
2195
2196         rcu_read_unlock();
2197         return ret;
2198 }
2199
2200 /*
2201  * Add context to a specific event in a channel for global UST domain.
2202  */
2203 int ust_app_add_ctx_event_glb(struct ltt_ust_session *usess,
2204                 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent,
2205                 struct ltt_ust_context *uctx)
2206 {
2207         int ret = 0;
2208         struct cds_lfht_node *ua_chan_node, *ua_event_node;
2209         struct cds_lfht_iter iter, uiter;
2210         struct ust_app_session *ua_sess;
2211         struct ust_app_event *ua_event;
2212         struct ust_app_channel *ua_chan = NULL;
2213         struct ust_app *app;
2214
2215         rcu_read_lock();
2216
2217         cds_lfht_for_each_entry(ust_app_ht, &iter, app, node) {
2218                 ua_sess = lookup_session_by_app(usess, app);
2219                 if (ua_sess == NULL) {
2220                         continue;
2221                 }
2222
2223                 /* Lookup channel in the ust app session */
2224                 ua_chan_node = hashtable_lookup(ua_sess->channels,
2225                                 (void *)uchan->name, strlen(uchan->name), &uiter);
2226                 if (ua_chan_node == NULL) {
2227                         continue;
2228                 }
2229                 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel,
2230                                 node);
2231
2232                 ua_event_node = hashtable_lookup(ua_chan->events,
2233                                 (void *)uevent->attr.name, strlen(uevent->attr.name), &uiter);
2234                 if (ua_event_node == NULL) {
2235                         continue;
2236                 }
2237                 ua_event = caa_container_of(ua_event_node, struct ust_app_event,
2238                                 node);
2239
2240                 ret = create_ust_app_event_context(ua_sess, ua_event, &uctx->ctx, app);
2241                 if (ret < 0) {
2242                         continue;
2243                 }
2244         }
2245
2246         /* Add ltt UST context node to ltt UST event */
2247         hashtable_add_unique(uevent->ctx, &uctx->node);
2248
2249         rcu_read_unlock();
2250         return ret;
2251 }