src/bin/lttng-sessiond/trace-ust.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 <stdio.h>
  20 #include <stdlib.h>
  21 #include <string.h>
  22 #include <unistd.h>
  23
  24 #include <common/common.h>
  25 #include <common/defaults.h>
  26
  27 #include "trace-ust.h"
  28
  29 /*
  30  * Match function for the events hash table lookup.
  31  *
  32  * Matches by name only. Used by the disable command.
  33  */
  34 int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
  35                 const void *_key)
  36 {
  37         struct ltt_ust_event *event;
  38         const char *name;
  39
  40         assert(node);
  41         assert(_key);
  42
  43         event = caa_container_of(node, struct ltt_ust_event, node.node);
  44         name = _key;
  45
  46         /* Event name */
  47         if (strncmp(event->attr.name, name, sizeof(event->attr.name)) != 0) {
  48                 goto no_match;
  49         }
  50
  51         /* Match */
  52         return 1;
  53
  54 no_match:
  55         return 0;
  56 }
  57
  58 /*
  59  * Match function for the hash table lookup.
  60  *
  61  * It matches an ust event based on three attributes which are the event name,
  62  * the filter bytecode and the loglevel.
  63  */
  64 int trace_ust_ht_match_event(struct cds_lfht_node *node, const void *_key)
  65 {
  66         struct ltt_ust_event *event;
  67         const struct ltt_ust_ht_key *key;
  68
  69         assert(node);
  70         assert(_key);
  71
  72         event = caa_container_of(node, struct ltt_ust_event, node.node);
  73         key = _key;
  74
  75         /* Match the 3 elements of the key: name, filter and loglevel. */
  76
  77         /* Event name */
  78         if (strncmp(event->attr.name, key->name, sizeof(event->attr.name)) != 0) {
  79                 goto no_match;
  80         }
  81
  82         /* Event loglevel. */
  83         if (event->attr.loglevel != key->loglevel) {
  84                 if (event->attr.loglevel_type == LTTNG_UST_LOGLEVEL_ALL
  85                                 && key->loglevel == 0 && event->attr.loglevel == -1) {
  86                         /*
  87                          * Match is accepted. This is because on event creation, the
  88                          * loglevel is set to -1 if the event loglevel type is ALL so 0 and
  89                          * -1 are accepted for this loglevel type since 0 is the one set by
  90                          * the API when receiving an enable event.
  91                          */
  92                 } else {
  93                         goto no_match;
  94                 }
  95         }
  96
  97         /* Only one of the filters is NULL, fail. */
  98         if ((key->filter && !event->filter) || (!key->filter && event->filter)) {
  99                 goto no_match;
 100         }
 101
 102         if (key->filter && event->filter) {
 103                 /* Both filters exists, check length followed by the bytecode. */
 104                 if (event->filter->len != key->filter->len ||
 105                                 memcmp(event->filter->data, key->filter->data,
 106                                         event->filter->len) != 0) {
 107                         goto no_match;
 108                 }
 109         }
 110
 111         /* Match. */
 112         return 1;
 113
 114 no_match:
 115         return 0;
 116 }
 117
 118 /*
 119  * Find the channel in the hashtable.
 120  */
 121 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 122                 char *name)
 123 {
 124         struct lttng_ht_node_str *node;
 125         struct lttng_ht_iter iter;
 126
 127         rcu_read_lock();
 128         lttng_ht_lookup(ht, (void *)name, &iter);
 129         node = lttng_ht_iter_get_node_str(&iter);
 130         if (node == NULL) {
 131                 rcu_read_unlock();
 132                 goto error;
 133         }
 134         rcu_read_unlock();
 135
 136         DBG2("Trace UST channel %s found by name", name);
 137
 138         return caa_container_of(node, struct ltt_ust_channel, node);
 139
 140 error:
 141         DBG2("Trace UST channel %s not found by name", name);
 142         return NULL;
 143 }
 144
 145 /*
 146  * Find the event in the hashtable.
 147  */
 148 struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
 149                 char *name, struct lttng_filter_bytecode *filter, int loglevel)
 150 {
 151         struct lttng_ht_node_str *node;
 152         struct lttng_ht_iter iter;
 153         struct ltt_ust_ht_key key;
 154
 155         assert(name);
 156         assert(ht);
 157
 158         key.name = name;
 159         key.filter = filter;
 160         key.loglevel = loglevel;
 161
 162         cds_lfht_lookup(ht->ht, ht->hash_fct((void *) name, lttng_ht_seed),
 163                         trace_ust_ht_match_event, &key, &iter.iter);
 164         node = lttng_ht_iter_get_node_str(&iter);
 165         if (node == NULL) {
 166                 goto error;
 167         }
 168
 169         DBG2("Trace UST event %s found", key.name);
 170
 171         return caa_container_of(node, struct ltt_ust_event, node);
 172
 173 error:
 174         DBG2("Trace UST event %s NOT found", key.name);
 175         return NULL;
 176 }
 177
 178 /*
 179  * Allocate and initialize a ust session data structure.
 180  *
 181  * Return pointer to structure or NULL.
 182  */
 183 struct ltt_ust_session *trace_ust_create_session(char *path,
 184                 unsigned int session_id)
 185 {
 186         struct ltt_ust_session *lus;
 187
 188         /* Allocate a new ltt ust session */
 189         lus = zmalloc(sizeof(struct ltt_ust_session));
 190         if (lus == NULL) {
 191                 PERROR("create ust session zmalloc");
 192                 goto error;
 193         }
 194
 195         /* Init data structure */
 196         lus->id = session_id;
 197         lus->start_trace = 0;
 198
 199         /* Alloc UST domain hash tables */
 200         lus->domain_pid = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
 201         lus->domain_exec = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
 202
 203         /* Alloc UST global domain channels' HT */
 204         lus->domain_global.channels = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
 205
 206         lus->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
 207         if (lus->consumer == NULL) {
 208                 goto error_consumer;
 209         }
 210
 211         /*
 212          * The tmp_consumer stays NULL until a set_consumer_uri command is
 213          * executed. At this point, the consumer should be nullify until an
 214          * enable_consumer command. This assignment is symbolic since we've zmalloc
 215          * the struct.
 216          */
 217         lus->tmp_consumer = NULL;
 218
 219         /* Use the default consumer output which is the tracing session path. */
 220         if (path && strlen(path) > 0) {
 221                 int ret;
 222
 223                 ret = snprintf(lus->consumer->dst.trace_path, PATH_MAX,
 224                                 "%s" DEFAULT_UST_TRACE_DIR, path);
 225                 if (ret < 0) {
 226                         PERROR("snprintf UST consumer trace path");
 227                         goto error_path;
 228                 }
 229
 230                 /* Set session path */
 231                 ret = snprintf(lus->pathname, PATH_MAX, "%s" DEFAULT_UST_TRACE_DIR,
 232                                 path);
 233                 if (ret < 0) {
 234                         PERROR("snprintf kernel traces path");
 235                         goto error_path;
 236                 }
 237         }
 238
 239         DBG2("UST trace session create successful");
 240
 241         return lus;
 242
 243 error_path:
 244         consumer_destroy_output(lus->consumer);
 245 error_consumer:
 246         lttng_ht_destroy(lus->domain_global.channels);
 247         lttng_ht_destroy(lus->domain_exec);
 248         lttng_ht_destroy(lus->domain_pid);
 249         free(lus);
 250 error:
 251         return NULL;
 252 }
 253
 254 /*
 255  * Allocate and initialize a ust channel data structure.
 256  *
 257  * Return pointer to structure or NULL.
 258  */
 259 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *chan,
 260                 char *path)
 261 {
 262         int ret;
 263         struct ltt_ust_channel *luc;
 264
 265         assert(chan);
 266         assert(path);
 267
 268         luc = zmalloc(sizeof(struct ltt_ust_channel));
 269         if (luc == NULL) {
 270                 PERROR("ltt_ust_channel zmalloc");
 271                 goto error;
 272         }
 273
 274         /* Copy UST channel attributes */
 275         luc->attr.overwrite = chan->attr.overwrite;
 276         luc->attr.subbuf_size = chan->attr.subbuf_size;
 277         luc->attr.num_subbuf = chan->attr.num_subbuf;
 278         luc->attr.switch_timer_interval = chan->attr.switch_timer_interval;
 279         luc->attr.read_timer_interval = chan->attr.read_timer_interval;
 280         luc->attr.output = (enum lttng_ust_output) chan->attr.output;
 281
 282         /* Translate to UST output enum */
 283         switch (luc->attr.output) {
 284         default:
 285                 luc->attr.output = LTTNG_UST_MMAP;
 286                 break;
 287         }
 288
 289         /* Copy channel name */
 290         strncpy(luc->name, chan->name, sizeof(luc->name));
 291         luc->name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
 292
 293         /* Init node */
 294         lttng_ht_node_init_str(&luc->node, luc->name);
 295         /* Alloc hash tables */
 296         luc->events = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
 297         luc->ctx = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
 298
 299         /* Set trace output path */
 300         ret = snprintf(luc->pathname, PATH_MAX, "%s", path);
 301         if (ret < 0) {
 302                 PERROR("asprintf ust create channel");
 303                 goto error_free_channel;
 304         }
 305
 306         DBG2("Trace UST channel %s created", luc->name);
 307
 308         return luc;
 309
 310 error_free_channel:
 311         lttng_ht_destroy(luc->ctx);
 312         lttng_ht_destroy(luc->events);
 313         free(luc);
 314 error:
 315         return NULL;
 316 }
 317
 318 /*
 319  * Allocate and initialize a ust event. Set name and event type.
 320  *
 321  * Return pointer to structure or NULL.
 322  */
 323 struct ltt_ust_event *trace_ust_create_event(struct lttng_event *ev,
 324                 struct lttng_filter_bytecode *filter)
 325 {
 326         struct ltt_ust_event *lue;
 327
 328         assert(ev);
 329
 330         lue = zmalloc(sizeof(struct ltt_ust_event));
 331         if (lue == NULL) {
 332                 PERROR("ust event zmalloc");
 333                 goto error;
 334         }
 335
 336         switch (ev->type) {
 337         case LTTNG_EVENT_PROBE:
 338                 lue->attr.instrumentation = LTTNG_UST_PROBE;
 339                 break;
 340         case LTTNG_EVENT_FUNCTION:
 341                 lue->attr.instrumentation = LTTNG_UST_FUNCTION;
 342                 break;
 343         case LTTNG_EVENT_FUNCTION_ENTRY:
 344                 lue->attr.instrumentation = LTTNG_UST_FUNCTION;
 345                 break;
 346         case LTTNG_EVENT_TRACEPOINT:
 347                 lue->attr.instrumentation = LTTNG_UST_TRACEPOINT;
 348                 break;
 349         default:
 350                 ERR("Unknown ust instrumentation type (%d)", ev->type);
 351                 goto error_free_event;
 352         }
 353
 354         /* Copy event name */
 355         strncpy(lue->attr.name, ev->name, LTTNG_UST_SYM_NAME_LEN);
 356         lue->attr.name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
 357
 358         switch (ev->loglevel_type) {
 359         case LTTNG_EVENT_LOGLEVEL_ALL:
 360                 lue->attr.loglevel_type = LTTNG_UST_LOGLEVEL_ALL;
 361                 lue->attr.loglevel = -1;        /* Force to -1 */
 362                 break;
 363         case LTTNG_EVENT_LOGLEVEL_RANGE:
 364                 lue->attr.loglevel_type = LTTNG_UST_LOGLEVEL_RANGE;
 365                 lue->attr.loglevel = ev->loglevel;
 366                 break;
 367         case LTTNG_EVENT_LOGLEVEL_SINGLE:
 368                 lue->attr.loglevel_type = LTTNG_UST_LOGLEVEL_SINGLE;
 369                 lue->attr.loglevel = ev->loglevel;
 370                 break;
 371         default:
 372                 ERR("Unknown ust loglevel type (%d)", ev->loglevel_type);
 373                 goto error_free_event;
 374         }
 375
 376         /* Same layout. */
 377         lue->filter = (struct lttng_ust_filter_bytecode *) filter;
 378
 379         /* Init node */
 380         lttng_ht_node_init_str(&lue->node, lue->attr.name);
 381
 382         DBG2("Trace UST event %s, loglevel (%d,%d) created",
 383                 lue->attr.name, lue->attr.loglevel_type,
 384                 lue->attr.loglevel);
 385
 386         return lue;
 387
 388 error_free_event:
 389         free(lue);
 390 error:
 391         return NULL;
 392 }
 393
 394 /*
 395  * Allocate and initialize a ust metadata.
 396  *
 397  * Return pointer to structure or NULL.
 398  */
 399 struct ltt_ust_metadata *trace_ust_create_metadata(char *path)
 400 {
 401         int ret;
 402         struct ltt_ust_metadata *lum;
 403
 404         assert(path);
 405
 406         lum = zmalloc(sizeof(struct ltt_ust_metadata));
 407         if (lum == NULL) {
 408                 PERROR("ust metadata zmalloc");
 409                 goto error;
 410         }
 411
 412         /* Set default attributes */
 413         lum->attr.overwrite = DEFAULT_CHANNEL_OVERWRITE;
 414         lum->attr.subbuf_size = default_get_metadata_subbuf_size();
 415         lum->attr.num_subbuf = DEFAULT_METADATA_SUBBUF_NUM;
 416         lum->attr.switch_timer_interval = DEFAULT_CHANNEL_SWITCH_TIMER;
 417         lum->attr.read_timer_interval = DEFAULT_CHANNEL_READ_TIMER;
 418         lum->attr.output = LTTNG_UST_MMAP;
 419
 420         lum->handle = -1;
 421         /* Set metadata trace path */
 422         ret = snprintf(lum->pathname, PATH_MAX, "%s/metadata", path);
 423         if (ret < 0) {
 424                 PERROR("asprintf ust metadata");
 425                 goto error_free_metadata;
 426         }
 427
 428         return lum;
 429
 430 error_free_metadata:
 431         free(lum);
 432 error:
 433         return NULL;
 434 }
 435
 436 /*
 437  * Allocate and initialize an UST context.
 438  *
 439  * Return pointer to structure or NULL.
 440  */
 441 struct ltt_ust_context *trace_ust_create_context(
 442                 struct lttng_event_context *ctx)
 443 {
 444         struct ltt_ust_context *uctx;
 445         enum lttng_ust_context_type utype;
 446
 447         assert(ctx);
 448
 449         switch (ctx->ctx) {
 450         case LTTNG_EVENT_CONTEXT_VTID:
 451                 utype = LTTNG_UST_CONTEXT_VTID;
 452                 break;
 453         case LTTNG_EVENT_CONTEXT_VPID:
 454                 utype = LTTNG_UST_CONTEXT_VPID;
 455                 break;
 456         case LTTNG_EVENT_CONTEXT_PTHREAD_ID:
 457                 utype = LTTNG_UST_CONTEXT_PTHREAD_ID;
 458                 break;
 459         case LTTNG_EVENT_CONTEXT_PROCNAME:
 460                 utype = LTTNG_UST_CONTEXT_PROCNAME;
 461                 break;
 462         default:
 463                 ERR("Invalid UST context");
 464                 return NULL;
 465         }
 466
 467         uctx = zmalloc(sizeof(struct ltt_ust_context));
 468         if (uctx == NULL) {
 469                 PERROR("zmalloc ltt_ust_context");
 470                 goto error;
 471         }
 472
 473         uctx->ctx.ctx = utype;
 474         lttng_ht_node_init_ulong(&uctx->node, (unsigned long) uctx->ctx.ctx);
 475
 476         return uctx;
 477
 478 error:
 479         return NULL;
 480 }
 481
 482 /*
 483  * RCU safe free context structure.
 484  */
 485 static void destroy_context_rcu(struct rcu_head *head)
 486 {
 487         struct lttng_ht_node_ulong *node =
 488                 caa_container_of(head, struct lttng_ht_node_ulong, head);
 489         struct ltt_ust_context *ctx =
 490                 caa_container_of(node, struct ltt_ust_context, node);
 491
 492         free(ctx);
 493 }
 494
 495 /*
 496  * Cleanup UST context hash table.
 497  */
 498 static void destroy_contexts(struct lttng_ht *ht)
 499 {
 500         int ret;
 501         struct lttng_ht_node_ulong *node;
 502         struct lttng_ht_iter iter;
 503
 504         assert(ht);
 505
 506         cds_lfht_for_each_entry(ht->ht, &iter.iter, node, node) {
 507                 ret = lttng_ht_del(ht, &iter);
 508                 if (!ret) {
 509                         call_rcu(&node->head, destroy_context_rcu);
 510                 }
 511         }
 512
 513         lttng_ht_destroy(ht);
 514 }
 515
 516 /*
 517  * Cleanup ust event structure.
 518  */
 519 void trace_ust_destroy_event(struct ltt_ust_event *event)
 520 {
 521         assert(event);
 522
 523         DBG2("Trace destroy UST event %s", event->attr.name);
 524         free(event->filter);
 525         free(event);
 526 }
 527
 528 /*
 529  * URCU intermediate call to complete destroy event.
 530  */
 531 static void destroy_event_rcu(struct rcu_head *head)
 532 {
 533         struct lttng_ht_node_str *node =
 534                 caa_container_of(head, struct lttng_ht_node_str, head);
 535         struct ltt_ust_event *event =
 536                 caa_container_of(node, struct ltt_ust_event, node);
 537
 538         trace_ust_destroy_event(event);
 539 }
 540
 541 /*
 542  * Cleanup UST events hashtable.
 543  */
 544 static void destroy_events(struct lttng_ht *events)
 545 {
 546         int ret;
 547         struct lttng_ht_node_str *node;
 548         struct lttng_ht_iter iter;
 549
 550         assert(events);
 551
 552         cds_lfht_for_each_entry(events->ht, &iter.iter, node, node) {
 553                 ret = lttng_ht_del(events, &iter);
 554                 assert(!ret);
 555                 call_rcu(&node->head, destroy_event_rcu);
 556         }
 557
 558         lttng_ht_destroy(events);
 559 }
 560
 561 /*
 562  * Cleanup ust channel structure.
 563  */
 564 void trace_ust_destroy_channel(struct ltt_ust_channel *channel)
 565 {
 566         assert(channel);
 567
 568         DBG2("Trace destroy UST channel %s", channel->name);
 569
 570         rcu_read_lock();
 571
 572         /* Destroying all events of the channel */
 573         destroy_events(channel->events);
 574         /* Destroying all context of the channel */
 575         destroy_contexts(channel->ctx);
 576
 577         free(channel);
 578
 579         rcu_read_unlock();
 580 }
 581
 582 /*
 583  * URCU intermediate call to complete destroy channel.
 584  */
 585 static void destroy_channel_rcu(struct rcu_head *head)
 586 {
 587         struct lttng_ht_node_str *node =
 588                 caa_container_of(head, struct lttng_ht_node_str, head);
 589         struct ltt_ust_channel *channel =
 590                 caa_container_of(node, struct ltt_ust_channel, node);
 591
 592         trace_ust_destroy_channel(channel);
 593 }
 594
 595 /*
 596  * Cleanup ust metadata structure.
 597  */
 598 void trace_ust_destroy_metadata(struct ltt_ust_metadata *metadata)
 599 {
 600         assert(metadata);
 601
 602         if (!metadata->handle) {
 603                 return;
 604         }
 605         DBG2("Trace UST destroy metadata %d", metadata->handle);
 606         free(metadata);
 607 }
 608
 609 /*
 610  * Iterate over a hash table containing channels and cleanup safely.
 611  */
 612 static void destroy_channels(struct lttng_ht *channels)
 613 {
 614         int ret;
 615         struct lttng_ht_node_str *node;
 616         struct lttng_ht_iter iter;
 617
 618         assert(channels);
 619
 620         rcu_read_lock();
 621
 622         cds_lfht_for_each_entry(channels->ht, &iter.iter, node, node) {
 623                 ret = lttng_ht_del(channels, &iter);
 624                 assert(!ret);
 625                 call_rcu(&node->head, destroy_channel_rcu);
 626         }
 627
 628         lttng_ht_destroy(channels);
 629
 630         rcu_read_unlock();
 631 }
 632
 633 /*
 634  * Cleanup UST pid domain.
 635  */
 636 static void destroy_domain_pid(struct lttng_ht *ht)
 637 {
 638         int ret;
 639         struct lttng_ht_iter iter;
 640         struct ltt_ust_domain_pid *dpid;
 641
 642         assert(ht);
 643
 644         cds_lfht_for_each_entry(ht->ht, &iter.iter, dpid, node.node) {
 645                 ret = lttng_ht_del(ht , &iter);
 646                 assert(!ret);
 647                 destroy_channels(dpid->channels);
 648         }
 649
 650         lttng_ht_destroy(ht);
 651 }
 652
 653 /*
 654  * Cleanup UST exec name domain.
 655  */
 656 static void destroy_domain_exec(struct lttng_ht *ht)
 657 {
 658         int ret;
 659         struct lttng_ht_iter iter;
 660         struct ltt_ust_domain_exec *dexec;
 661
 662         assert(ht);
 663
 664         cds_lfht_for_each_entry(ht->ht, &iter.iter, dexec, node.node) {
 665                 ret = lttng_ht_del(ht , &iter);
 666                 assert(!ret);
 667                 destroy_channels(dexec->channels);
 668         }
 669
 670         lttng_ht_destroy(ht);
 671 }
 672
 673 /*
 674  * Cleanup UST global domain.
 675  */
 676 static void destroy_domain_global(struct ltt_ust_domain_global *dom)
 677 {
 678         assert(dom);
 679
 680         destroy_channels(dom->channels);
 681 }
 682
 683 /*
 684  * Cleanup ust session structure
 685  */
 686 void trace_ust_destroy_session(struct ltt_ust_session *session)
 687 {
 688         assert(session);
 689
 690         rcu_read_lock();
 691
 692         DBG2("Trace UST destroy session %u", session->id);
 693
 694         /* Cleaning up UST domain */
 695         destroy_domain_global(&session->domain_global);
 696         destroy_domain_pid(session->domain_pid);
 697         destroy_domain_exec(session->domain_exec);
 698
 699         consumer_destroy_output(session->consumer);
 700         consumer_destroy_output(session->tmp_consumer);
 701
 702         free(session);
 703
 704         rcu_read_unlock();
 705 }