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 #include <inttypes.h>
  24
  25 #include <common/common.h>
  26 #include <common/defaults.h>
  27
  28 #include "buffer-registry.h"
  29 #include "trace-ust.h"
  30 #include "utils.h"
  31
  32 /*
  33  * Match function for the events hash table lookup.
  34  *
  35  * Matches by name only. Used by the disable command.
  36  */
  37 int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
  38                 const void *_key)
  39 {
  40         struct ltt_ust_event *event;
  41         const char *name;
  42
  43         assert(node);
  44         assert(_key);
  45
  46         event = caa_container_of(node, struct ltt_ust_event, node.node);
  47         name = _key;
  48
  49         /* Event name */
  50         if (strncmp(event->attr.name, name, sizeof(event->attr.name)) != 0) {
  51                 goto no_match;
  52         }
  53
  54         /* Match */
  55         return 1;
  56
  57 no_match:
  58         return 0;
  59 }
  60
  61 /*
  62  * Match function for the hash table lookup.
  63  *
  64  * It matches an ust event based on three attributes which are the event name,
  65  * the filter bytecode and the loglevel.
  66  */
  67 int trace_ust_ht_match_event(struct cds_lfht_node *node, const void *_key)
  68 {
  69         struct ltt_ust_event *event;
  70         const struct ltt_ust_ht_key *key;
  71
  72         assert(node);
  73         assert(_key);
  74
  75         event = caa_container_of(node, struct ltt_ust_event, node.node);
  76         key = _key;
  77
  78         /* Match the 3 elements of the key: name, filter and loglevel. */
  79
  80         /* Event name */
  81         if (strncmp(event->attr.name, key->name, sizeof(event->attr.name)) != 0) {
  82                 goto no_match;
  83         }
  84
  85         /* Event loglevel. */
  86         if (event->attr.loglevel != key->loglevel) {
  87                 if (event->attr.loglevel_type == LTTNG_UST_LOGLEVEL_ALL
  88                                 && key->loglevel == 0 && event->attr.loglevel == -1) {
  89                         /*
  90                          * Match is accepted. This is because on event creation, the
  91                          * loglevel is set to -1 if the event loglevel type is ALL so 0 and
  92                          * -1 are accepted for this loglevel type since 0 is the one set by
  93                          * the API when receiving an enable event.
  94                          */
  95                 } else {
  96                         goto no_match;
  97                 }
  98         }
  99
 100         /* Only one of the filters is NULL, fail. */
 101         if ((key->filter && !event->filter) || (!key->filter && event->filter)) {
 102                 goto no_match;
 103         }
 104
 105         if (key->filter && event->filter) {
 106                 /* Both filters exists, check length followed by the bytecode. */
 107                 if (event->filter->len != key->filter->len ||
 108                                 memcmp(event->filter->data, key->filter->data,
 109                                         event->filter->len) != 0) {
 110                         goto no_match;
 111                 }
 112         }
 113
 114         /* Match. */
 115         return 1;
 116
 117 no_match:
 118         return 0;
 119 }
 120
 121 /*
 122  * Find the channel in the hashtable and return channel pointer. RCU read side
 123  * lock MUST be acquired before calling this.
 124  */
 125 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 126                 char *name)
 127 {
 128         struct lttng_ht_node_str *node;
 129         struct lttng_ht_iter iter;
 130
 131         /*
 132          * If we receive an empty string for channel name, it means the
 133          * default channel name is requested.
 134          */
 135         if (name[0] == '\0')
 136                 name = DEFAULT_CHANNEL_NAME;
 137
 138         lttng_ht_lookup(ht, (void *)name, &iter);
 139         node = lttng_ht_iter_get_node_str(&iter);
 140         if (node == NULL) {
 141                 goto error;
 142         }
 143
 144         DBG2("Trace UST channel %s found by name", name);
 145
 146         return caa_container_of(node, struct ltt_ust_channel, node);
 147
 148 error:
 149         DBG2("Trace UST channel %s not found by name", name);
 150         return NULL;
 151 }
 152
 153 /*
 154  * Find the event in the hashtable and return event pointer. RCU read side lock
 155  * MUST be acquired before calling this.
 156  */
 157 struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
 158                 char *name, struct lttng_filter_bytecode *filter, int loglevel)
 159 {
 160         struct lttng_ht_node_str *node;
 161         struct lttng_ht_iter iter;
 162         struct ltt_ust_ht_key key;
 163
 164         assert(name);
 165         assert(ht);
 166
 167         key.name = name;
 168         key.filter = filter;
 169         key.loglevel = loglevel;
 170
 171         cds_lfht_lookup(ht->ht, ht->hash_fct((void *) name, lttng_ht_seed),
 172                         trace_ust_ht_match_event, &key, &iter.iter);
 173         node = lttng_ht_iter_get_node_str(&iter);
 174         if (node == NULL) {
 175                 goto error;
 176         }
 177
 178         DBG2("Trace UST event %s found", key.name);
 179
 180         return caa_container_of(node, struct ltt_ust_event, node);
 181
 182 error:
 183         DBG2("Trace UST event %s NOT found", key.name);
 184         return NULL;
 185 }
 186
 187 /*
 188  * Allocate and initialize a ust session data structure.
 189  *
 190  * Return pointer to structure or NULL.
 191  */
 192 struct ltt_ust_session *trace_ust_create_session(uint64_t session_id)
 193 {
 194         int ret;
 195         struct ltt_ust_session *lus;
 196
 197         /* Allocate a new ltt ust session */
 198         lus = zmalloc(sizeof(struct ltt_ust_session));
 199         if (lus == NULL) {
 200                 PERROR("create ust session zmalloc");
 201                 goto error;
 202         }
 203
 204         /* Init data structure */
 205         lus->id = session_id;
 206         lus->start_trace = 0;
 207
 208         /*
 209          * Default buffer type. This can be changed through an enable channel
 210          * requesting a different type. Note that this can only be changed once
 211          * during the session lifetime which is at the first enable channel and
 212          * only before start. The flag buffer_type_changed indicates the status.
 213          */
 214         lus->buffer_type = LTTNG_BUFFER_PER_UID;
 215         /* Once set to 1, the buffer_type is immutable for the session. */
 216         lus->buffer_type_changed = 0;
 217         /* Init it in case it get used after allocation. */
 218         CDS_INIT_LIST_HEAD(&lus->buffer_reg_uid_list);
 219
 220         /* Alloc UST global domain channels' HT */
 221         lus->domain_global.channels = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
 222         ret = jul_init_domain(&lus->domain_jul);
 223         if (ret < 0) {
 224                 goto error_consumer;
 225         }
 226
 227         lus->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
 228         if (lus->consumer == NULL) {
 229                 goto error_consumer;
 230         }
 231
 232         /*
 233          * The tmp_consumer stays NULL until a set_consumer_uri command is
 234          * executed. At this point, the consumer should be nullify until an
 235          * enable_consumer command. This assignment is symbolic since we've zmalloc
 236          * the struct.
 237          */
 238         lus->tmp_consumer = NULL;
 239
 240         DBG2("UST trace session create successful");
 241
 242         return lus;
 243
 244 error_consumer:
 245         ht_cleanup_push(lus->domain_global.channels);
 246         jul_destroy_domain(&lus->domain_jul);
 247         free(lus);
 248 error:
 249         return NULL;
 250 }
 251
 252 /*
 253  * Allocate and initialize a ust channel data structure.
 254  *
 255  * Return pointer to structure or NULL.
 256  */
 257 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *chan)
 258 {
 259         struct ltt_ust_channel *luc;
 260
 261         assert(chan);
 262
 263         luc = zmalloc(sizeof(struct ltt_ust_channel));
 264         if (luc == NULL) {
 265                 PERROR("ltt_ust_channel zmalloc");
 266                 goto error;
 267         }
 268
 269         /* Copy UST channel attributes */
 270         luc->attr.overwrite = chan->attr.overwrite;
 271         luc->attr.subbuf_size = chan->attr.subbuf_size;
 272         luc->attr.num_subbuf = chan->attr.num_subbuf;
 273         luc->attr.switch_timer_interval = chan->attr.switch_timer_interval;
 274         luc->attr.read_timer_interval = chan->attr.read_timer_interval;
 275         luc->attr.output = (enum lttng_ust_output) chan->attr.output;
 276
 277         /* Translate to UST output enum */
 278         switch (luc->attr.output) {
 279         default:
 280                 luc->attr.output = LTTNG_UST_MMAP;
 281                 break;
 282         }
 283
 284         /*
 285          * If we receive an empty string for channel name, it means the
 286          * default channel name is requested.
 287          */
 288         if (chan->name[0] == '\0') {
 289                 strncpy(luc->name, DEFAULT_CHANNEL_NAME, sizeof(luc->name));
 290         } else {
 291                 /* Copy channel name */
 292                 strncpy(luc->name, chan->name, sizeof(luc->name));
 293         }
 294         luc->name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
 295
 296         /* Init node */
 297         lttng_ht_node_init_str(&luc->node, luc->name);
 298         CDS_INIT_LIST_HEAD(&luc->ctx_list);
 299
 300         /* Alloc hash tables */
 301         luc->events = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
 302         luc->ctx = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
 303
 304         /* On-disk circular buffer parameters */
 305         luc->tracefile_size = chan->attr.tracefile_size;
 306         luc->tracefile_count = chan->attr.tracefile_count;
 307
 308         DBG2("Trace UST channel %s created", luc->name);
 309
 310 error:
 311         return luc;
 312 }
 313
 314 /*
 315  * Allocate and initialize a ust event. Set name and event type.
 316  *
 317  * Return pointer to structure or NULL.
 318  */
 319 struct ltt_ust_event *trace_ust_create_event(struct lttng_event *ev,
 320                 struct lttng_filter_bytecode *filter)
 321 {
 322         struct ltt_ust_event *lue;
 323
 324         assert(ev);
 325
 326         lue = zmalloc(sizeof(struct ltt_ust_event));
 327         if (lue == NULL) {
 328                 PERROR("ust event zmalloc");
 329                 goto error;
 330         }
 331
 332         switch (ev->type) {
 333         case LTTNG_EVENT_PROBE:
 334                 lue->attr.instrumentation = LTTNG_UST_PROBE;
 335                 break;
 336         case LTTNG_EVENT_FUNCTION:
 337                 lue->attr.instrumentation = LTTNG_UST_FUNCTION;
 338                 break;
 339         case LTTNG_EVENT_FUNCTION_ENTRY:
 340                 lue->attr.instrumentation = LTTNG_UST_FUNCTION;
 341                 break;
 342         case LTTNG_EVENT_TRACEPOINT:
 343                 lue->attr.instrumentation = LTTNG_UST_TRACEPOINT;
 344                 break;
 345         default:
 346                 ERR("Unknown ust instrumentation type (%d)", ev->type);
 347                 goto error_free_event;
 348         }
 349
 350         /* Copy event name */
 351         strncpy(lue->attr.name, ev->name, LTTNG_UST_SYM_NAME_LEN);
 352         lue->attr.name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
 353
 354         switch (ev->loglevel_type) {
 355         case LTTNG_EVENT_LOGLEVEL_ALL:
 356                 lue->attr.loglevel_type = LTTNG_UST_LOGLEVEL_ALL;
 357                 lue->attr.loglevel = -1;        /* Force to -1 */
 358                 break;
 359         case LTTNG_EVENT_LOGLEVEL_RANGE:
 360                 lue->attr.loglevel_type = LTTNG_UST_LOGLEVEL_RANGE;
 361                 lue->attr.loglevel = ev->loglevel;
 362                 break;
 363         case LTTNG_EVENT_LOGLEVEL_SINGLE:
 364                 lue->attr.loglevel_type = LTTNG_UST_LOGLEVEL_SINGLE;
 365                 lue->attr.loglevel = ev->loglevel;
 366                 break;
 367         default:
 368                 ERR("Unknown ust loglevel type (%d)", ev->loglevel_type);
 369                 goto error_free_event;
 370         }
 371
 372         /* Same layout. */
 373         lue->filter = (struct lttng_ust_filter_bytecode *) filter;
 374
 375         /* Init node */
 376         lttng_ht_node_init_str(&lue->node, lue->attr.name);
 377
 378         DBG2("Trace UST event %s, loglevel (%d,%d) created",
 379                 lue->attr.name, lue->attr.loglevel_type,
 380                 lue->attr.loglevel);
 381
 382         return lue;
 383
 384 error_free_event:
 385         free(lue);
 386 error:
 387         return NULL;
 388 }
 389
 390 /*
 391  * Allocate and initialize a ust metadata.
 392  *
 393  * Return pointer to structure or NULL.
 394  */
 395 struct ltt_ust_metadata *trace_ust_create_metadata(char *path)
 396 {
 397         int ret;
 398         struct ltt_ust_metadata *lum;
 399
 400         assert(path);
 401
 402         lum = zmalloc(sizeof(struct ltt_ust_metadata));
 403         if (lum == NULL) {
 404                 PERROR("ust metadata zmalloc");
 405                 goto error;
 406         }
 407
 408         /* Set default attributes */
 409         lum->attr.overwrite = DEFAULT_CHANNEL_OVERWRITE;
 410         lum->attr.subbuf_size = default_get_metadata_subbuf_size();
 411         lum->attr.num_subbuf = DEFAULT_METADATA_SUBBUF_NUM;
 412         lum->attr.switch_timer_interval = DEFAULT_METADATA_SWITCH_TIMER;
 413         lum->attr.read_timer_interval = DEFAULT_METADATA_READ_TIMER;
 414         lum->attr.output = LTTNG_UST_MMAP;
 415
 416         lum->handle = -1;
 417         /* Set metadata trace path */
 418         ret = snprintf(lum->pathname, PATH_MAX, "%s/" DEFAULT_METADATA_NAME, path);
 419         if (ret < 0) {
 420                 PERROR("asprintf ust metadata");
 421                 goto error_free_metadata;
 422         }
 423
 424         return lum;
 425
 426 error_free_metadata:
 427         free(lum);
 428 error:
 429         return NULL;
 430 }
 431
 432 /*
 433  * Allocate and initialize an UST context.
 434  *
 435  * Return pointer to structure or NULL.
 436  */
 437 struct ltt_ust_context *trace_ust_create_context(
 438                 struct lttng_event_context *ctx)
 439 {
 440         struct ltt_ust_context *uctx;
 441         enum lttng_ust_context_type utype;
 442
 443         assert(ctx);
 444
 445         switch (ctx->ctx) {
 446         case LTTNG_EVENT_CONTEXT_VTID:
 447                 utype = LTTNG_UST_CONTEXT_VTID;
 448                 break;
 449         case LTTNG_EVENT_CONTEXT_VPID:
 450                 utype = LTTNG_UST_CONTEXT_VPID;
 451                 break;
 452         case LTTNG_EVENT_CONTEXT_PTHREAD_ID:
 453                 utype = LTTNG_UST_CONTEXT_PTHREAD_ID;
 454                 break;
 455         case LTTNG_EVENT_CONTEXT_PROCNAME:
 456                 utype = LTTNG_UST_CONTEXT_PROCNAME;
 457                 break;
 458         case LTTNG_EVENT_CONTEXT_IP:
 459                 utype = LTTNG_UST_CONTEXT_IP;
 460                 break;
 461         default:
 462                 ERR("Invalid UST context");
 463                 return NULL;
 464         }
 465
 466         uctx = zmalloc(sizeof(struct ltt_ust_context));
 467         if (uctx == NULL) {
 468                 PERROR("zmalloc ltt_ust_context");
 469                 goto error;
 470         }
 471
 472         uctx->ctx.ctx = utype;
 473         lttng_ht_node_init_ulong(&uctx->node, (unsigned long) uctx->ctx.ctx);
 474         CDS_INIT_LIST_HEAD(&uctx->list);
 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         struct ltt_ust_context *ctx;
 504
 505         assert(ht);
 506
 507         rcu_read_lock();
 508         cds_lfht_for_each_entry(ht->ht, &iter.iter, node, node) {
 509                 /* Remove from ordered list. */
 510                 ctx = caa_container_of(node, struct ltt_ust_context, node);
 511                 cds_list_del(&ctx->list);
 512                 /* Remove from channel's hash table. */
 513                 ret = lttng_ht_del(ht, &iter);
 514                 if (!ret) {
 515                         call_rcu(&node->head, destroy_context_rcu);
 516                 }
 517         }
 518         rcu_read_unlock();
 519
 520         ht_cleanup_push(ht);
 521 }
 522
 523 /*
 524  * Cleanup ust event structure.
 525  */
 526 void trace_ust_destroy_event(struct ltt_ust_event *event)
 527 {
 528         assert(event);
 529
 530         DBG2("Trace destroy UST event %s", event->attr.name);
 531         free(event->filter);
 532         free(event);
 533 }
 534
 535 /*
 536  * URCU intermediate call to complete destroy event.
 537  */
 538 static void destroy_event_rcu(struct rcu_head *head)
 539 {
 540         struct lttng_ht_node_str *node =
 541                 caa_container_of(head, struct lttng_ht_node_str, head);
 542         struct ltt_ust_event *event =
 543                 caa_container_of(node, struct ltt_ust_event, node);
 544
 545         trace_ust_destroy_event(event);
 546 }
 547
 548 /*
 549  * Cleanup UST events hashtable.
 550  */
 551 static void destroy_events(struct lttng_ht *events)
 552 {
 553         int ret;
 554         struct lttng_ht_node_str *node;
 555         struct lttng_ht_iter iter;
 556
 557         assert(events);
 558
 559         rcu_read_lock();
 560         cds_lfht_for_each_entry(events->ht, &iter.iter, node, node) {
 561                 ret = lttng_ht_del(events, &iter);
 562                 assert(!ret);
 563                 call_rcu(&node->head, destroy_event_rcu);
 564         }
 565         rcu_read_unlock();
 566
 567         ht_cleanup_push(events);
 568 }
 569
 570 /*
 571  * Cleanup ust channel structure.
 572  *
 573  * Should _NOT_ be called with RCU read lock held.
 574  */
 575 static void _trace_ust_destroy_channel(struct ltt_ust_channel *channel)
 576 {
 577         assert(channel);
 578
 579         DBG2("Trace destroy UST channel %s", channel->name);
 580
 581         /* Destroying all events of the channel */
 582         destroy_events(channel->events);
 583         /* Destroying all context of the channel */
 584         destroy_contexts(channel->ctx);
 585
 586         free(channel);
 587 }
 588
 589 /*
 590  * URCU intermediate call to complete destroy channel.
 591  */
 592 static void destroy_channel_rcu(struct rcu_head *head)
 593 {
 594         struct lttng_ht_node_str *node =
 595                 caa_container_of(head, struct lttng_ht_node_str, head);
 596         struct ltt_ust_channel *channel =
 597                 caa_container_of(node, struct ltt_ust_channel, node);
 598
 599         _trace_ust_destroy_channel(channel);
 600 }
 601
 602 void trace_ust_destroy_channel(struct ltt_ust_channel *channel)
 603 {
 604         call_rcu(&channel->node.head, destroy_channel_rcu);
 605 }
 606
 607 /*
 608  * Remove an UST channel from a channel HT.
 609  */
 610 void trace_ust_delete_channel(struct lttng_ht *ht,
 611                 struct ltt_ust_channel *channel)
 612 {
 613         int ret;
 614         struct lttng_ht_iter iter;
 615
 616         assert(ht);
 617         assert(channel);
 618
 619         iter.iter.node = &channel->node.node;
 620         ret = lttng_ht_del(ht, &iter);
 621         assert(!ret);
 622 }
 623
 624 /*
 625  * Cleanup ust metadata structure.
 626  */
 627 void trace_ust_destroy_metadata(struct ltt_ust_metadata *metadata)
 628 {
 629         assert(metadata);
 630
 631         if (!metadata->handle) {
 632                 return;
 633         }
 634         DBG2("Trace UST destroy metadata %d", metadata->handle);
 635         free(metadata);
 636 }
 637
 638 /*
 639  * Iterate over a hash table containing channels and cleanup safely.
 640  */
 641 static void destroy_channels(struct lttng_ht *channels)
 642 {
 643         int ret;
 644         struct lttng_ht_node_str *node;
 645         struct lttng_ht_iter iter;
 646
 647         assert(channels);
 648
 649         rcu_read_lock();
 650
 651         cds_lfht_for_each_entry(channels->ht, &iter.iter, node, node) {
 652                 ret = lttng_ht_del(channels, &iter);
 653                 assert(!ret);
 654                 call_rcu(&node->head, destroy_channel_rcu);
 655         }
 656         rcu_read_unlock();
 657
 658         ht_cleanup_push(channels);
 659 }
 660
 661 /*
 662  * Cleanup UST global domain.
 663  */
 664 static void destroy_domain_global(struct ltt_ust_domain_global *dom)
 665 {
 666         assert(dom);
 667
 668         destroy_channels(dom->channels);
 669 }
 670
 671 /*
 672  * Cleanup ust session structure
 673  *
 674  * Should *NOT* be called with RCU read-side lock held.
 675  */
 676 void trace_ust_destroy_session(struct ltt_ust_session *session)
 677 {
 678         struct buffer_reg_uid *reg, *sreg;
 679
 680         assert(session);
 681
 682         DBG2("Trace UST destroy session %" PRIu64, session->id);
 683
 684         /* Cleaning up UST domain */
 685         destroy_domain_global(&session->domain_global);
 686         jul_destroy_domain(&session->domain_jul);
 687
 688         /* Cleanup UID buffer registry object(s). */
 689         cds_list_for_each_entry_safe(reg, sreg, &session->buffer_reg_uid_list,
 690                         lnode) {
 691                 cds_list_del(&reg->lnode);
 692                 buffer_reg_uid_remove(reg);
 693                 buffer_reg_uid_destroy(reg, session->consumer);
 694         }
 695
 696         consumer_destroy_output(session->consumer);
 697         consumer_destroy_output(session->tmp_consumer);
 698
 699         free(session);
 700 }