src/bin/lttng-sessiond/event.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 modify
   5  * it under the terms of the GNU General Public License, version 2 only,
   6  * as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  16  */
  17
  18 #define _GNU_SOURCE
  19 #include <errno.h>
  20 #include <urcu/list.h>
  21 #include <string.h>
  22
  23 #include <lttng/lttng.h>
  24 #include <common/error.h>
  25 #include <common/sessiond-comm/sessiond-comm.h>
  26
  27 #include "channel.h"
  28 #include "event.h"
  29 #include "kernel.h"
  30 #include "lttng-sessiond.h"
  31 #include "ust-ctl.h"
  32 #include "ust-app.h"
  33 #include "trace-kernel.h"
  34 #include "trace-ust.h"
  35
  36 /*
  37  * Add unique UST event based on the event name, filter bytecode and loglevel.
  38  */
  39 static void add_unique_ust_event(struct lttng_ht *ht,
  40                 struct ltt_ust_event *event)
  41 {
  42         struct cds_lfht_node *node_ptr;
  43         struct ltt_ust_ht_key key;
  44
  45         assert(ht);
  46         assert(ht->ht);
  47         assert(event);
  48
  49         key.name = event->attr.name;
  50         key.filter = (struct lttng_filter_bytecode *) event->filter;
  51         key.loglevel = event->attr.loglevel;
  52         key.exclusion = event->exclusion;
  53
  54         node_ptr = cds_lfht_add_unique(ht->ht,
  55                         ht->hash_fct(event->node.key, lttng_ht_seed),
  56                         trace_ust_ht_match_event, &key, &event->node.node);
  57         assert(node_ptr == &event->node.node);
  58 }
  59
  60 /*
  61  * Setup a lttng_event used to enable *all* syscall tracing.
  62  */
  63 static void init_syscalls_kernel_event(struct lttng_event *event)
  64 {
  65         assert(event);
  66
  67         event->name[0] = '\0';
  68         /*
  69          * We use LTTNG_EVENT* here since the trace kernel creation will make the
  70          * right changes for the kernel.
  71          */
  72         event->type = LTTNG_EVENT_SYSCALL;
  73 }
  74
  75 /*
  76  * Disable kernel tracepoint event for a channel from the kernel session.
  77  */
  78 int event_kernel_disable_tracepoint(struct ltt_kernel_channel *kchan,
  79                 char *event_name)
  80 {
  81         int ret;
  82         struct ltt_kernel_event *kevent;
  83
  84         assert(kchan);
  85
  86         kevent = trace_kernel_get_event_by_name(event_name, kchan);
  87         if (kevent == NULL) {
  88                 ret = LTTNG_ERR_NO_EVENT;
  89                 goto error;
  90         }
  91
  92         ret = kernel_disable_event(kevent);
  93         if (ret < 0) {
  94                 ret = LTTNG_ERR_KERN_DISABLE_FAIL;
  95                 goto error;
  96         }
  97
  98         DBG("Kernel event %s disable for channel %s.",
  99                         kevent->event->name, kchan->channel->name);
 100
 101         ret = LTTNG_OK;
 102
 103 error:
 104         return ret;
 105 }
 106
 107 /*
 108  * Disable kernel tracepoint events for a channel from the kernel session.
 109  */
 110 int event_kernel_disable_all_tracepoints(struct ltt_kernel_channel *kchan)
 111 {
 112         int ret;
 113         struct ltt_kernel_event *kevent;
 114
 115         assert(kchan);
 116
 117         /* For each event in the kernel session */
 118         cds_list_for_each_entry(kevent, &kchan->events_list.head, list) {
 119                 ret = kernel_disable_event(kevent);
 120                 if (ret < 0) {
 121                         /* We continue disabling the rest */
 122                         continue;
 123                 }
 124         }
 125         ret = LTTNG_OK;
 126         return ret;
 127 }
 128
 129 /*
 130  * Disable kernel syscall events for a channel from the kernel session.
 131  */
 132 int event_kernel_disable_all_syscalls(struct ltt_kernel_channel *kchan)
 133 {
 134         ERR("Cannot disable syscall tracing for existing session. Please destroy session instead.");
 135         return LTTNG_OK;        /* Return OK so disable all succeeds */
 136 }
 137
 138 /*
 139  * Disable all kernel event for a channel from the kernel session.
 140  */
 141 int event_kernel_disable_all(struct ltt_kernel_channel *kchan)
 142 {
 143         int ret;
 144
 145         assert(kchan);
 146
 147         ret = event_kernel_disable_all_tracepoints(kchan);
 148         if (ret != LTTNG_OK)
 149                 return ret;
 150         ret = event_kernel_disable_all_syscalls(kchan);
 151         return ret;
 152 }
 153
 154 /*
 155  * Enable kernel tracepoint event for a channel from the kernel session.
 156  */
 157 int event_kernel_enable_tracepoint(struct ltt_kernel_channel *kchan,
 158                 struct lttng_event *event)
 159 {
 160         int ret;
 161         struct ltt_kernel_event *kevent;
 162
 163         assert(kchan);
 164         assert(event);
 165
 166         kevent = trace_kernel_get_event_by_name(event->name, kchan);
 167         if (kevent == NULL) {
 168                 ret = kernel_create_event(event, kchan);
 169                 if (ret < 0) {
 170                         switch (-ret) {
 171                         case EEXIST:
 172                                 ret = LTTNG_ERR_KERN_EVENT_EXIST;
 173                                 break;
 174                         case ENOSYS:
 175                                 ret = LTTNG_ERR_KERN_EVENT_ENOSYS;
 176                                 break;
 177                         default:
 178                                 ret = LTTNG_ERR_KERN_ENABLE_FAIL;
 179                                 break;
 180                         }
 181                         goto end;
 182                 }
 183         } else if (kevent->enabled == 0) {
 184                 ret = kernel_enable_event(kevent);
 185                 if (ret < 0) {
 186                         ret = LTTNG_ERR_KERN_ENABLE_FAIL;
 187                         goto end;
 188                 }
 189         } else {
 190                 /* At this point, the event is considered enabled */
 191                 ret = LTTNG_ERR_KERN_EVENT_EXIST;
 192                 goto end;
 193         }
 194
 195         ret = LTTNG_OK;
 196 end:
 197         return ret;
 198 }
 199
 200 /*
 201  * Enable all kernel tracepoint events of a channel of the kernel session.
 202  */
 203 int event_kernel_enable_all_tracepoints(struct ltt_kernel_channel *kchan,
 204                 int kernel_tracer_fd)
 205 {
 206         int size, i, ret;
 207         struct ltt_kernel_event *kevent;
 208         struct lttng_event *event_list = NULL;
 209
 210         assert(kchan);
 211
 212         /* For each event in the kernel session */
 213         cds_list_for_each_entry(kevent, &kchan->events_list.head, list) {
 214                 if (kevent->enabled == 0) {
 215                         ret = kernel_enable_event(kevent);
 216                         if (ret < 0) {
 217                                 /* Enable failed but still continue */
 218                                 continue;
 219                         }
 220                 }
 221         }
 222
 223         size = kernel_list_events(kernel_tracer_fd, &event_list);
 224         if (size < 0) {
 225                 ret = LTTNG_ERR_KERN_LIST_FAIL;
 226                 goto end;
 227         }
 228
 229         for (i = 0; i < size; i++) {
 230                 kevent = trace_kernel_get_event_by_name(event_list[i].name, kchan);
 231                 if (kevent == NULL) {
 232                         /* Default event type for enable all */
 233                         event_list[i].type = LTTNG_EVENT_TRACEPOINT;
 234                         /* Enable each single tracepoint event */
 235                         ret = kernel_create_event(&event_list[i], kchan);
 236                         if (ret < 0) {
 237                                 /* Ignore error here and continue */
 238                         }
 239                 }
 240         }
 241         free(event_list);
 242
 243         ret = LTTNG_OK;
 244 end:
 245         return ret;
 246 }
 247
 248 /*
 249  * Enable all kernel sycalls events of a channel of the kernel session.
 250  */
 251 int event_kernel_enable_all_syscalls(struct ltt_kernel_channel *kchan,
 252                 int kernel_tracer_fd)
 253 {
 254         int ret;
 255         struct lttng_event event;
 256
 257         assert(kchan);
 258
 259         init_syscalls_kernel_event(&event);
 260
 261         DBG("Enabling all syscall tracing");
 262
 263         ret = kernel_create_event(&event, kchan);
 264         if (ret < 0) {
 265                 if (ret == -EEXIST) {
 266                         ret = LTTNG_ERR_KERN_EVENT_EXIST;
 267                 } else {
 268                         ret = LTTNG_ERR_KERN_ENABLE_FAIL;
 269                 }
 270                 goto end;
 271         }
 272
 273         ret = LTTNG_OK;
 274 end:
 275         return ret;
 276 }
 277
 278 /*
 279  * Enable all kernel events of a channel of the kernel session.
 280  */
 281 int event_kernel_enable_all(struct ltt_kernel_channel *kchan,
 282                 int kernel_tracer_fd)
 283 {
 284         int tp_ret;
 285
 286         assert(kchan);
 287
 288         tp_ret = event_kernel_enable_all_tracepoints(kchan, kernel_tracer_fd);
 289         if (tp_ret != LTTNG_OK) {
 290                 goto end;
 291         }
 292
 293         /*
 294          * Reaching this code path means that all tracepoints were enabled without
 295          * errors so we ignore the error value of syscalls.
 296          *
 297          * At the moment, failing to enable syscalls on "lttng enable-event -a -k"
 298          * is not considered an error that need to be returned to the client since
 299          * tracepoints did not fail. Future work will allow us to send back
 300          * multiple errors to the client in one API call.
 301          */
 302         (void) event_kernel_enable_all_syscalls(kchan, kernel_tracer_fd);
 303
 304 end:
 305         return tp_ret;
 306 }
 307
 308 /*
 309  * ============================
 310  * UST : The Ultimate Frontier!
 311  * ============================
 312  */
 313
 314 /*
 315  * Enable all UST tracepoints for a channel from a UST session.
 316  */
 317 int event_ust_enable_all_tracepoints(struct ltt_ust_session *usess,
 318                 struct ltt_ust_channel *uchan, struct lttng_filter_bytecode *filter)
 319 {
 320         int ret, i, size;
 321         struct lttng_ht_iter iter;
 322         struct ltt_ust_event *uevent = NULL;
 323         struct lttng_event *events = NULL;
 324
 325         assert(usess);
 326         assert(uchan);
 327
 328         rcu_read_lock();
 329
 330         /* Enable existing events */
 331         cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent,
 332                         node.node) {
 333                 if (uevent->enabled == 0) {
 334                         ret = ust_app_enable_event_glb(usess, uchan, uevent);
 335                         if (ret < 0) {
 336                                 continue;
 337                         }
 338                         uevent->enabled = 1;
 339                 }
 340         }
 341
 342         /* Get all UST available events */
 343         size = ust_app_list_events(&events);
 344         if (size < 0) {
 345                 ret = LTTNG_ERR_UST_LIST_FAIL;
 346                 goto error;
 347         }
 348
 349         for (i = 0; i < size; i++) {
 350                 /*
 351                  * Check if event exist and if so, continue since it was enable
 352                  * previously.
 353                  */
 354                 uevent = trace_ust_find_event(uchan->events, events[i].name, filter,
 355                                 events[i].loglevel, NULL);
 356                 if (uevent != NULL) {
 357                         ret = ust_app_enable_event_pid(usess, uchan, uevent,
 358                                         events[i].pid);
 359                         if (ret < 0) {
 360                                 if (ret != -LTTNG_UST_ERR_EXIST) {
 361                                         ret = LTTNG_ERR_UST_ENABLE_FAIL;
 362                                         goto error;
 363                                 }
 364                         }
 365                         continue;
 366                 }
 367
 368                 /* Create ust event */
 369                 uevent = trace_ust_create_event(&events[i], filter, NULL);
 370                 if (uevent == NULL) {
 371                         ret = LTTNG_ERR_FATAL;
 372                         goto error_destroy;
 373                 }
 374
 375                 /* Create event for the specific PID */
 376                 ret = ust_app_enable_event_pid(usess, uchan, uevent,
 377                                 events[i].pid);
 378                 if (ret < 0) {
 379                         if (ret == -LTTNG_UST_ERR_EXIST) {
 380                                 ret = LTTNG_ERR_UST_EVENT_EXIST;
 381                                 goto error;
 382                         } else {
 383                                 ret = LTTNG_ERR_UST_ENABLE_FAIL;
 384                                 goto error_destroy;
 385                         }
 386                 }
 387
 388                 uevent->enabled = 1;
 389                 /* Add ltt ust event to channel */
 390                 rcu_read_lock();
 391                 add_unique_ust_event(uchan->events, uevent);
 392                 rcu_read_unlock();
 393         }
 394         free(events);
 395
 396         rcu_read_unlock();
 397         return LTTNG_OK;
 398
 399 error_destroy:
 400         trace_ust_destroy_event(uevent);
 401
 402 error:
 403         free(events);
 404         rcu_read_unlock();
 405         return ret;
 406 }
 407
 408 /*
 409  * Enable UST tracepoint event for a channel from a UST session.
 410  */
 411 int event_ust_enable_tracepoint(struct ltt_ust_session *usess,
 412                 struct ltt_ust_channel *uchan, struct lttng_event *event,
 413                 struct lttng_filter_bytecode *filter,
 414                 struct lttng_event_exclusion *exclusion)
 415 {
 416         int ret = LTTNG_OK, to_create = 0;
 417         struct ltt_ust_event *uevent;
 418
 419         assert(usess);
 420         assert(uchan);
 421         assert(event);
 422
 423         rcu_read_lock();
 424
 425         uevent = trace_ust_find_event(uchan->events, event->name, filter,
 426                         event->loglevel, exclusion);
 427         if (uevent == NULL) {
 428                 uevent = trace_ust_create_event(event, filter, exclusion);
 429                 if (uevent == NULL) {
 430                         ret = LTTNG_ERR_UST_ENABLE_FAIL;
 431                         goto error;
 432                 }
 433
 434                 /* Valid to set it after the goto error since uevent is still NULL */
 435                 to_create = 1;
 436         }
 437
 438         if (uevent->enabled) {
 439                 /* It's already enabled so everything is OK */
 440                 ret = LTTNG_ERR_UST_EVENT_ENABLED;
 441                 goto end;
 442         }
 443
 444         uevent->enabled = 1;
 445
 446         if (to_create) {
 447                 /* Create event on all UST registered apps for session */
 448                 ret = ust_app_create_event_glb(usess, uchan, uevent);
 449         } else {
 450                 /* Enable event on all UST registered apps for session */
 451                 ret = ust_app_enable_event_glb(usess, uchan, uevent);
 452         }
 453
 454         if (ret < 0) {
 455                 if (ret == -LTTNG_UST_ERR_EXIST) {
 456                         ret = LTTNG_ERR_UST_EVENT_EXIST;
 457                         goto end;
 458                 } else {
 459                         ret = LTTNG_ERR_UST_ENABLE_FAIL;
 460                         goto error;
 461                 }
 462         }
 463
 464         if (to_create) {
 465                 /* Add ltt ust event to channel */
 466                 add_unique_ust_event(uchan->events, uevent);
 467         }
 468
 469         DBG("Event UST %s %s in channel %s", uevent->attr.name,
 470                         to_create ? "created" : "enabled", uchan->name);
 471
 472         ret = LTTNG_OK;
 473
 474 end:
 475         rcu_read_unlock();
 476         return ret;
 477
 478 error:
 479         /*
 480          * Only destroy event on creation time (not enabling time) because if the
 481          * event is found in the channel (to_create == 0), it means that at some
 482          * point the enable_event worked and it's thus valid to keep it alive.
 483          * Destroying it also implies that we also destroy it's shadow copy to sync
 484          * everyone up.
 485          */
 486         if (to_create) {
 487                 /* In this code path, the uevent was not added to the hash table */
 488                 trace_ust_destroy_event(uevent);
 489         }
 490         rcu_read_unlock();
 491         return ret;
 492 }
 493
 494 /*
 495  * Disable UST tracepoint of a channel from a UST session.
 496  */
 497 int event_ust_disable_tracepoint(struct ltt_ust_session *usess,
 498                 struct ltt_ust_channel *uchan, char *event_name)
 499 {
 500         int ret;
 501         struct ltt_ust_event *uevent;
 502         struct lttng_ht_node_str *node;
 503         struct lttng_ht_iter iter;
 504         struct lttng_ht *ht;
 505
 506         assert(usess);
 507         assert(uchan);
 508         assert(event_name);
 509
 510         ht = uchan->events;
 511
 512         rcu_read_lock();
 513
 514         /*
 515          * We use a custom lookup since we need the iterator for the next_duplicate
 516          * call in the do while loop below.
 517          */
 518         cds_lfht_lookup(ht->ht, ht->hash_fct((void *) event_name, lttng_ht_seed),
 519                         trace_ust_ht_match_event_by_name, event_name, &iter.iter);
 520         node = lttng_ht_iter_get_node_str(&iter);
 521         if (node == NULL) {
 522                 DBG2("Trace UST event NOT found by name %s", event_name);
 523                 ret = LTTNG_ERR_UST_EVENT_NOT_FOUND;
 524                 goto error;
 525         }
 526
 527         do {
 528                 uevent = caa_container_of(node, struct ltt_ust_event, node);
 529                 assert(uevent);
 530
 531                 if (uevent->enabled == 0) {
 532                         /* It's already disabled so everything is OK */
 533                         goto next;
 534                 }
 535
 536                 ret = ust_app_disable_event_glb(usess, uchan, uevent);
 537                 if (ret < 0 && ret != -LTTNG_UST_ERR_EXIST) {
 538                         ret = LTTNG_ERR_UST_DISABLE_FAIL;
 539                         goto error;
 540                 }
 541                 uevent->enabled = 0;
 542
 543                 DBG2("Event UST %s disabled in channel %s", uevent->attr.name,
 544                                 uchan->name);
 545
 546 next:
 547                 /* Get next duplicate event by name. */
 548                 cds_lfht_next_duplicate(ht->ht, trace_ust_ht_match_event_by_name,
 549                                 event_name, &iter.iter);
 550                 node = lttng_ht_iter_get_node_str(&iter);
 551         } while (node);
 552
 553         ret = LTTNG_OK;
 554
 555 error:
 556         rcu_read_unlock();
 557         return ret;
 558 }
 559
 560 /*
 561  * Disable all UST tracepoints for a channel from a UST session.
 562  */
 563 int event_ust_disable_all_tracepoints(struct ltt_ust_session *usess,
 564                 struct ltt_ust_channel *uchan)
 565 {
 566         int ret, i, size;
 567         struct lttng_ht_iter iter;
 568         struct ltt_ust_event *uevent = NULL;
 569         struct lttng_event *events = NULL;
 570
 571         assert(usess);
 572         assert(uchan);
 573
 574         rcu_read_lock();
 575
 576         /* Disabling existing events */
 577         cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent,
 578                         node.node) {
 579                 if (uevent->enabled == 1) {
 580                         ret = event_ust_disable_tracepoint(usess, uchan,
 581                                         uevent->attr.name);
 582                         if (ret < 0) {
 583                                 continue;
 584                         }
 585                 }
 586         }
 587
 588         /* Get all UST available events */
 589         size = ust_app_list_events(&events);
 590         if (size < 0) {
 591                 ret = LTTNG_ERR_UST_LIST_FAIL;
 592                 goto error;
 593         }
 594
 595         for (i = 0; i < size; i++) {
 596                 ret = event_ust_disable_tracepoint(usess, uchan,
 597                                 events[i].name);
 598                 if (ret != LTTNG_OK) {
 599                         /* Continue to disable the rest... */
 600                         continue;
 601                 }
 602         }
 603         free(events);
 604
 605         rcu_read_unlock();
 606         return LTTNG_OK;
 607
 608 error:
 609         free(events);
 610         rcu_read_unlock();
 611         return ret;
 612 }
 613
 614 /*
 615  * Enable all JUL event for a given UST session.
 616  *
 617  * Return LTTNG_OK on success or else a LTTNG_ERR* code.
 618  */
 619 int event_jul_enable_all(struct ltt_ust_session *usess,
 620                 struct lttng_event *event, struct lttng_filter_bytecode *filter)
 621 {
 622         int ret;
 623         struct jul_event *jevent;
 624         struct lttng_ht_iter iter;
 625
 626         assert(usess);
 627
 628         DBG("Event JUL enabling ALL events for session %" PRIu64, usess->id);
 629
 630         /* Enable event on JUL application through TCP socket. */
 631         ret = event_jul_enable(usess, event, filter);
 632         if (ret != LTTNG_OK) {
 633                 goto error;
 634         }
 635
 636         /* Flag every event that they are now enabled. */
 637         rcu_read_lock();
 638         cds_lfht_for_each_entry(usess->domain_jul.events->ht, &iter.iter, jevent,
 639                         node.node) {
 640                 jevent->enabled = 1;
 641         }
 642         rcu_read_unlock();
 643
 644         ret = LTTNG_OK;
 645
 646 error:
 647         return ret;
 648 }
 649
 650 /*
 651  * Enable a single JUL event for a given UST session.
 652  *
 653  * Return LTTNG_OK on success or else a LTTNG_ERR* code.
 654  */
 655 int event_jul_enable(struct ltt_ust_session *usess, struct lttng_event *event,
 656                 struct lttng_filter_bytecode *filter)
 657 {
 658         int ret, created = 0;
 659         struct jul_event *jevent;
 660
 661         assert(usess);
 662         assert(event);
 663
 664         DBG("Event JUL enabling %s for session %" PRIu64 " with loglevel type %d "
 665                         "and loglevel %d", event->name, usess->id, event->loglevel_type,
 666                         event->loglevel);
 667
 668         jevent = jul_find_event(event->name, event->loglevel, &usess->domain_jul);
 669         if (!jevent) {
 670                 jevent = jul_create_event(event->name);
 671                 if (!jevent) {
 672                         ret = LTTNG_ERR_NOMEM;
 673                         goto error;
 674                 }
 675                 jevent->loglevel = event->loglevel;
 676                 jevent->loglevel_type = event->loglevel_type;
 677                 jevent->filter = filter;
 678                 created = 1;
 679         }
 680
 681         /* Already enabled? */
 682         if (jevent->enabled) {
 683                 goto end;
 684         }
 685
 686         ret = jul_enable_event(jevent);
 687         if (ret != LTTNG_OK) {
 688                 goto error;
 689         }
 690
 691         /* If the event was created prior to the enable, add it to the domain. */
 692         if (created) {
 693                 jul_add_event(jevent, &usess->domain_jul);
 694         }
 695
 696 end:
 697         return LTTNG_OK;
 698
 699 error:
 700         if (created) {
 701                 jul_destroy_event(jevent);
 702         }
 703         return ret;
 704 }
 705
 706 /*
 707  * Disable a single JUL event for a given UST session.
 708  *
 709  * Return LTTNG_OK on success or else a LTTNG_ERR* code.
 710  */
 711 int event_jul_disable(struct ltt_ust_session *usess, char *event_name)
 712 {
 713         int ret;
 714         char *ust_event_name;
 715         struct jul_event *jevent;
 716         struct ltt_ust_event *uevent = NULL;
 717         struct ltt_ust_channel *uchan = NULL;
 718
 719         assert(usess);
 720         assert(event_name);
 721
 722         DBG("Event JUL disabling %s for session %" PRIu64, event_name, usess->id);
 723
 724         jevent = jul_find_event_by_name(event_name, &usess->domain_jul);
 725         if (!jevent) {
 726                 ret = LTTNG_ERR_UST_EVENT_NOT_FOUND;
 727                 goto error;
 728         }
 729
 730         /* Already disabled? */
 731         if (!jevent->enabled) {
 732                 goto end;
 733         }
 734
 735         /*
 736          * Disable it on the UST side. First get the channel reference then find
 737          * the event and finally disable it.
 738          */
 739         uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
 740                         DEFAULT_JUL_CHANNEL_NAME);
 741         if (!uchan) {
 742                 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
 743                 goto error;
 744         }
 745
 746         if (is_root) {
 747                 ust_event_name = DEFAULT_SYS_JUL_EVENT_NAME;
 748         } else {
 749                 ust_event_name = DEFAULT_USER_JUL_EVENT_NAME;
 750         }
 751
 752         /*
 753          * The loglevel is hardcoded with 0 here since the agent ust event is set
 754          * with the loglevel type to ALL thus the loglevel stays 0. The event's
 755          * filter is the one handling the loglevel for agent.
 756          */
 757         uevent = trace_ust_find_event(uchan->events, ust_event_name,
 758                         jevent->filter, 0, NULL);
 759         /* If the agent event exists, it must be available on the UST side. */
 760         assert(uevent);
 761
 762         ret = ust_app_disable_event_glb(usess, uchan, uevent);
 763         if (ret < 0 && ret != -LTTNG_UST_ERR_EXIST) {
 764                 ret = LTTNG_ERR_UST_DISABLE_FAIL;
 765                 goto error;
 766         }
 767         uevent->enabled = 0;
 768
 769         ret = jul_disable_event(jevent);
 770         if (ret != LTTNG_OK) {
 771                 goto error;
 772         }
 773
 774 end:
 775         return LTTNG_OK;
 776
 777 error:
 778         return ret;
 779 }
 780
 781 /*
 782  * Disable all JUL event for a given UST session.
 783  *
 784  * Return LTTNG_OK on success or else a LTTNG_ERR* code.
 785  */
 786 int event_jul_disable_all(struct ltt_ust_session *usess)
 787 {
 788         int ret;
 789         struct jul_event *jevent;
 790         struct lttng_ht_iter iter;
 791
 792         assert(usess);
 793
 794         /* Enable event on JUL application through TCP socket. */
 795         ret = event_jul_disable(usess, "*");
 796         if (ret != LTTNG_OK && ret != LTTNG_ERR_UST_EVENT_NOT_FOUND) {
 797                 goto error;
 798         }
 799
 800         /* Flag every event that they are now enabled. */
 801         rcu_read_lock();
 802         cds_lfht_for_each_entry(usess->domain_jul.events->ht, &iter.iter, jevent,
 803                         node.node) {
 804                 if (!jevent->enabled) {
 805                         continue;
 806                 }
 807
 808                 ret = event_jul_disable(usess, jevent->name);
 809                 if (ret != LTTNG_OK) {
 810                         rcu_read_unlock();
 811                         goto error;
 812                 }
 813         }
 814         rcu_read_unlock();
 815
 816         ret = LTTNG_OK;
 817
 818 error:
 819         return ret;
 820 }