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 int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
  30                 const void *_key)
  31 {
  32         struct ltt_ust_event *event;
  33         const char *name;
  34
  35         assert(node);
  36         assert(_key);
  37
  38         event = caa_container_of(node, struct ltt_ust_event, node.node);
  39         name = _key;
  40
  41         /* Event name */
  42         if (strncmp(event->attr.name, name, sizeof(event->attr.name)) != 0) {
  43                 goto no_match;
  44         }
  45
  46         /* Match. */
  47         return 1;
  48
  49 no_match:
  50         return 0;
  51 }
  52
  53 int trace_ust_ht_match_event(struct cds_lfht_node *node, const void *_key)
  54 {
  55         struct ltt_ust_event *event;
  56         const struct ltt_ust_ht_key *key;
  57
  58         assert(node);
  59         assert(_key);
  60
  61         event = caa_container_of(node, struct ltt_ust_event, node.node);
  62         key = _key;
  63
  64         /* Match the 3 elements of the key: name, filter and loglevel. */
  65
  66         /* Event name */
  67         if (strncmp(event->attr.name, key->name, sizeof(event->attr.name)) != 0) {
  68                 DBG3("[Match] name failed: %s and %s",
  69                                 event->attr.name, key->name);
  70                 goto no_match;
  71         }
  72
  73         /* Event loglevel. */
  74         if (event->attr.loglevel != key->loglevel) {
  75                 if (event->attr.loglevel_type == 0 && key->loglevel == 0 &&
  76                                 event->attr.loglevel == -1) {
  77                         /*
  78                          * This is because on event creation, the loglevel is set to -1 if
  79                          * the event loglevel type is ALL so 0 and -1 are accepted for this
  80                          * loglevel type.
  81                          */
  82                 } else {
  83                         DBG3("[Match] loglevel failed: %d and %d",
  84                                         event->attr.loglevel, key->loglevel);
  85                         goto no_match;
  86                 }
  87         }
  88
  89         /* Only one of the filters is NULL, fail. */
  90         if ((key->filter && !event->filter) || (!key->filter && event->filter)) {
  91                 DBG3("[Match] filters failed: k:%p and e:%p",
  92                                 key->filter, event->filter);
  93                 goto no_match;
  94         }
  95
  96         /* Both filters are NULL, success. */
  97         if (!key->filter && !event->filter) {
  98                 goto match;
  99         }
 100
 101         /* Both filters exists, check length followed by the bytecode. */
 102         if (event->filter->len == key->filter->len &&
 103                         memcmp(event->filter->data, key->filter->data,
 104                                 event->filter->len) == 0) {
 105                 goto match;
 106         }
 107
 108         DBG3("[Match] filters failed: k:%p and e:%p",
 109                         key->filter, event->filter);
 110
 111 no_match:
 112         return 0;
 113
 114 match:
 115         DBG3("[MATCH] %s", key->name);
 116         return 1;
 117 }
 118
 119 /*
 120  * Find the channel in the hashtable.
 121  */
 122 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 123                 char *name)
 124 {
 125         struct lttng_ht_node_str *node;
 126         struct lttng_ht_iter iter;
 127
 128         rcu_read_lock();
 129         lttng_ht_lookup(ht, (void *)name, &iter);
 130         node = lttng_ht_iter_get_node_str(&iter);
 131         if (node == NULL) {
 132                 rcu_read_unlock();
 133                 goto error;
 134         }
 135         rcu_read_unlock();
 136
 137         DBG2("Trace UST channel %s found by name", name);
 138
 139         return caa_container_of(node, struct ltt_ust_channel, node);
 140
 141 error:
 142         DBG2("Trace UST channel %s not found by name", name);
 143         return NULL;
 144 }
 145
 146 /*
 147  * Find the event in the hashtable.
 148  */
 149 struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
 150                 char *name, struct lttng_filter_bytecode *filter, int loglevel)
 151 {
 152         struct lttng_ht_node_str *node;
 153         struct lttng_ht_iter iter;
 154         struct ltt_ust_ht_key key;
 155         void *orig_match_fct;
 156
 157         assert(name);
 158         assert(ht);
 159
 160         key.name = name;
 161         key.filter = filter;
 162         key.loglevel = loglevel;
 163
 164         /* Save match function so we can use the ust app event match. */
 165         orig_match_fct = (void *) ht->match_fct;
 166         ht->match_fct = trace_ust_ht_match_event;
 167
 168         cds_lfht_lookup(ht->ht, ht->hash_fct((void *) name, lttng_ht_seed),
 169                         trace_ust_ht_match_event, &key, &iter.iter);
 170         node = lttng_ht_iter_get_node_str(&iter);
 171         if (node == NULL) {
 172                 goto error;
 173         }
 174
 175         DBG2("Trace UST event %s found", key.name);
 176
 177         return caa_container_of(node, struct ltt_ust_event, node);
 178
 179 error:
 180         DBG2("Trace UST event %s NOT found", key.name);
 181         /* Put back original match function. */
 182         ht->match_fct = orig_match_fct;
 183         return NULL;
 184 }
 185
 186 /*
 187  * Allocate and initialize a ust session data structure.
 188  *
 189  * Return pointer to structure or NULL.
 190  */
 191 struct ltt_ust_session *trace_ust_create_session(char *path,
 192                 unsigned int session_id, struct lttng_domain *domain)
 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         /* Alloc UST domain hash tables */
 209         lus->domain_pid = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
 210         lus->domain_exec = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
 211
 212         /* Alloc UST global domain channels' HT */
 213         lus->domain_global.channels = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
 214
 215         lus->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
 216         if (lus->consumer == NULL) {
 217                 goto error_consumer;
 218         }
 219
 220         /*
 221          * The tmp_consumer stays NULL until a set_consumer_uri command is
 222          * executed. At this point, the consumer should be nullify until an
 223          * enable_consumer command. This assignment is symbolic since we've zmalloc
 224          * the struct.
 225          */
 226         lus->tmp_consumer = NULL;
 227
 228         /* Use the default consumer output which is the tracing session path. */
 229         if (path && strlen(path) > 0) {
 230                 ret = snprintf(lus->consumer->dst.trace_path, PATH_MAX,
 231                                 "%s" DEFAULT_UST_TRACE_DIR, path);
 232                 if (ret < 0) {
 233                         PERROR("snprintf UST consumer trace path");
 234                         goto error_path;
 235                 }
 236
 237                 /* Set session path */
 238                 ret = snprintf(lus->pathname, PATH_MAX, "%s" DEFAULT_UST_TRACE_DIR,
 239                                 path);
 240                 if (ret < 0) {
 241                         PERROR("snprintf kernel traces path");
 242                         goto error_path;
 243                 }
 244         }
 245
 246         DBG2("UST trace session create successful");
 247
 248         return lus;
 249
 250 error_path:
 251         consumer_destroy_output(lus->consumer);
 252 error_consumer:
 253         lttng_ht_destroy(lus->domain_global.channels);
 254         lttng_ht_destroy(lus->domain_exec);
 255         lttng_ht_destroy(lus->domain_pid);
 256         free(lus);
 257 error:
 258         return NULL;
 259 }
 260
 261 /*
 262  * Allocate and initialize a ust channel data structure.
 263  *
 264  * Return pointer to structure or NULL.
 265  */
 266 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *chan,
 267                 char *path)
 268 {
 269         int ret;
 270         struct ltt_ust_channel *luc;
 271
 272         luc = zmalloc(sizeof(struct ltt_ust_channel));
 273         if (luc == NULL) {
 274                 PERROR("ltt_ust_channel zmalloc");
 275                 goto error;
 276         }
 277
 278         /* Copy UST channel attributes */
 279         luc->attr.overwrite = chan->attr.overwrite;
 280         luc->attr.subbuf_size = chan->attr.subbuf_size;
 281         luc->attr.num_subbuf = chan->attr.num_subbuf;
 282         luc->attr.switch_timer_interval = chan->attr.switch_timer_interval;
 283         luc->attr.read_timer_interval = chan->attr.read_timer_interval;
 284         luc->attr.output = (enum lttng_ust_output) chan->attr.output;
 285
 286         /* Translate to UST output enum */
 287         switch (luc->attr.output) {
 288         default:
 289                 luc->attr.output = LTTNG_UST_MMAP;
 290                 break;
 291         }
 292
 293         /* Copy channel name */
 294         strncpy(luc->name, chan->name, sizeof(luc->name));
 295         luc->name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
 296
 297         /* Init node */
 298         lttng_ht_node_init_str(&luc->node, luc->name);
 299         /* Alloc hash tables */
 300         luc->events = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
 301         luc->ctx = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
 302
 303         /* Set trace output path */
 304         ret = snprintf(luc->pathname, PATH_MAX, "%s", path);
 305         if (ret < 0) {
 306                 PERROR("asprintf ust create channel");
 307                 goto error_free_channel;
 308         }
 309
 310         DBG2("Trace UST channel %s created", luc->name);
 311
 312         return luc;
 313
 314 error_free_channel:
 315         lttng_ht_destroy(luc->ctx);
 316         lttng_ht_destroy(luc->events);
 317         free(luc);
 318 error:
 319         return NULL;
 320 }
 321
 322 /*
 323  * Allocate and initialize a ust event. Set name and event type.
 324  *
 325  * Return pointer to structure or NULL.
 326  */
 327 struct ltt_ust_event *trace_ust_create_event(struct lttng_event *ev)
 328 {
 329         struct ltt_ust_event *lue;
 330
 331         lue = zmalloc(sizeof(struct ltt_ust_event));
 332         if (lue == NULL) {
 333                 PERROR("ust event zmalloc");
 334                 goto error;
 335         }
 336
 337         switch (ev->type) {
 338         case LTTNG_EVENT_PROBE:
 339                 lue->attr.instrumentation = LTTNG_UST_PROBE;
 340                 break;
 341         case LTTNG_EVENT_FUNCTION:
 342                 lue->attr.instrumentation = LTTNG_UST_FUNCTION;
 343                 break;
 344         case LTTNG_EVENT_FUNCTION_ENTRY:
 345                 lue->attr.instrumentation = LTTNG_UST_FUNCTION;
 346                 break;
 347         case LTTNG_EVENT_TRACEPOINT:
 348                 lue->attr.instrumentation = LTTNG_UST_TRACEPOINT;
 349                 break;
 350         default:
 351                 ERR("Unknown ust instrumentation type (%d)", ev->type);
 352                 goto error_free_event;
 353         }
 354
 355         /* Copy event name */
 356         strncpy(lue->attr.name, ev->name, LTTNG_UST_SYM_NAME_LEN);
 357         lue->attr.name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
 358
 359         switch (ev->loglevel_type) {
 360         case LTTNG_EVENT_LOGLEVEL_ALL:
 361                 lue->attr.loglevel_type = LTTNG_UST_LOGLEVEL_ALL;
 362                 lue->attr.loglevel = -1;        /* Force to -1 */
 363                 break;
 364         case LTTNG_EVENT_LOGLEVEL_RANGE:
 365                 lue->attr.loglevel_type = LTTNG_UST_LOGLEVEL_RANGE;
 366                 lue->attr.loglevel = ev->loglevel;
 367                 break;
 368         case LTTNG_EVENT_LOGLEVEL_SINGLE:
 369                 lue->attr.loglevel_type = LTTNG_UST_LOGLEVEL_SINGLE;
 370                 lue->attr.loglevel = ev->loglevel;
 371                 break;
 372         default:
 373                 ERR("Unknown ust loglevel type (%d)", ev->loglevel_type);
 374                 goto error_free_event;
 375         }
 376
 377
 378         /* Init node */
 379         lttng_ht_node_init_str(&lue->node, lue->attr.name);
 380
 381         DBG2("Trace UST event %s, loglevel (%d,%d) created",
 382                 lue->attr.name, lue->attr.loglevel_type,
 383                 lue->attr.loglevel);
 384
 385         return lue;
 386
 387 error_free_event:
 388         free(lue);
 389 error:
 390         return NULL;
 391 }
 392
 393 /*
 394  * Allocate and initialize a ust metadata.
 395  *
 396  * Return pointer to structure or NULL.
 397  */
 398 struct ltt_ust_metadata *trace_ust_create_metadata(char *path)
 399 {
 400         int ret;
 401         struct ltt_ust_metadata *lum;
 402
 403         lum = zmalloc(sizeof(struct ltt_ust_metadata));
 404         if (lum == NULL) {
 405                 PERROR("ust metadata zmalloc");
 406                 goto error;
 407         }
 408
 409         /* Set default attributes */
 410         lum->attr.overwrite = DEFAULT_CHANNEL_OVERWRITE;
 411         lum->attr.subbuf_size = default_get_metadata_subbuf_size();
 412         lum->attr.num_subbuf = DEFAULT_METADATA_SUBBUF_NUM;
 413         lum->attr.switch_timer_interval = DEFAULT_CHANNEL_SWITCH_TIMER;
 414         lum->attr.read_timer_interval = DEFAULT_CHANNEL_READ_TIMER;
 415         lum->attr.output = LTTNG_UST_MMAP;
 416
 417         lum->handle = -1;
 418         /* Set metadata trace path */
 419         ret = snprintf(lum->pathname, PATH_MAX, "%s/metadata", path);
 420         if (ret < 0) {
 421                 PERROR("asprintf ust metadata");
 422                 goto error_free_metadata;
 423         }
 424
 425         return lum;
 426
 427 error_free_metadata:
 428         free(lum);
 429 error:
 430         return NULL;
 431 }
 432
 433 /*
 434  * Allocate and initialize an UST context.
 435  *
 436  * Return pointer to structure or NULL.
 437  */
 438 struct ltt_ust_context *trace_ust_create_context(
 439                 struct lttng_event_context *ctx)
 440 {
 441         struct ltt_ust_context *uctx;
 442         enum lttng_ust_context_type utype;
 443
 444         switch (ctx->ctx) {
 445         case LTTNG_EVENT_CONTEXT_VTID:
 446                 utype = LTTNG_UST_CONTEXT_VTID;
 447                 break;
 448         case LTTNG_EVENT_CONTEXT_VPID:
 449                 utype = LTTNG_UST_CONTEXT_VPID;
 450                 break;
 451         case LTTNG_EVENT_CONTEXT_PTHREAD_ID:
 452                 utype = LTTNG_UST_CONTEXT_PTHREAD_ID;
 453                 break;
 454         case LTTNG_EVENT_CONTEXT_PROCNAME:
 455                 utype = LTTNG_UST_CONTEXT_PROCNAME;
 456                 break;
 457         default:
 458                 ERR("Invalid UST context");
 459                 return NULL;
 460         }
 461
 462         uctx = zmalloc(sizeof(struct ltt_ust_context));
 463         if (uctx == NULL) {
 464                 PERROR("zmalloc ltt_ust_context");
 465                 goto error;
 466         }
 467
 468         uctx->ctx.ctx = utype;
 469         lttng_ht_node_init_ulong(&uctx->node, (unsigned long) uctx->ctx.ctx);
 470
 471         return uctx;
 472
 473 error:
 474         return NULL;
 475 }
 476
 477 /*
 478  * RCU safe free context structure.
 479  */
 480 static void destroy_context_rcu(struct rcu_head *head)
 481 {
 482         struct lttng_ht_node_ulong *node =
 483                 caa_container_of(head, struct lttng_ht_node_ulong, head);
 484         struct ltt_ust_context *ctx =
 485                 caa_container_of(node, struct ltt_ust_context, node);
 486
 487         free(ctx);
 488 }
 489
 490 /*
 491  * Cleanup UST context hash table.
 492  */
 493 static void destroy_contexts(struct lttng_ht *ht)
 494 {
 495         int ret;
 496         struct lttng_ht_node_ulong *node;
 497         struct lttng_ht_iter iter;
 498
 499         cds_lfht_for_each_entry(ht->ht, &iter.iter, node, node) {
 500                 ret = lttng_ht_del(ht, &iter);
 501                 if (!ret) {
 502                         call_rcu(&node->head, destroy_context_rcu);
 503                 }
 504         }
 505
 506         lttng_ht_destroy(ht);
 507 }
 508
 509 /*
 510  * Cleanup ust event structure.
 511  */
 512 void trace_ust_destroy_event(struct ltt_ust_event *event)
 513 {
 514         DBG2("Trace destroy UST event %s", event->attr.name);
 515         free(event->filter);
 516         free(event);
 517 }
 518
 519 /*
 520  * URCU intermediate call to complete destroy event.
 521  */
 522 static void destroy_event_rcu(struct rcu_head *head)
 523 {
 524         struct lttng_ht_node_str *node =
 525                 caa_container_of(head, struct lttng_ht_node_str, head);
 526         struct ltt_ust_event *event =
 527                 caa_container_of(node, struct ltt_ust_event, node);
 528
 529         trace_ust_destroy_event(event);
 530 }
 531
 532 /*
 533  * Cleanup UST events hashtable.
 534  */
 535 static void destroy_events(struct lttng_ht *events)
 536 {
 537         int ret;
 538         struct lttng_ht_node_str *node;
 539         struct lttng_ht_iter iter;
 540
 541         cds_lfht_for_each_entry(events->ht, &iter.iter, node, node) {
 542                 ret = lttng_ht_del(events, &iter);
 543                 assert(!ret);
 544                 call_rcu(&node->head, destroy_event_rcu);
 545         }
 546
 547         lttng_ht_destroy(events);
 548 }
 549
 550 /*
 551  * Cleanup ust channel structure.
 552  */
 553 void trace_ust_destroy_channel(struct ltt_ust_channel *channel)
 554 {
 555         DBG2("Trace destroy UST channel %s", channel->name);
 556
 557         rcu_read_lock();
 558
 559         /* Destroying all events of the channel */
 560         destroy_events(channel->events);
 561         /* Destroying all context of the channel */
 562         destroy_contexts(channel->ctx);
 563
 564         free(channel);
 565
 566         rcu_read_unlock();
 567 }
 568
 569 /*
 570  * URCU intermediate call to complete destroy channel.
 571  */
 572 static void destroy_channel_rcu(struct rcu_head *head)
 573 {
 574         struct lttng_ht_node_str *node =
 575                 caa_container_of(head, struct lttng_ht_node_str, head);
 576         struct ltt_ust_channel *channel =
 577                 caa_container_of(node, struct ltt_ust_channel, node);
 578
 579         trace_ust_destroy_channel(channel);
 580 }
 581
 582 /*
 583  * Cleanup ust metadata structure.
 584  */
 585 void trace_ust_destroy_metadata(struct ltt_ust_metadata *metadata)
 586 {
 587         if (!metadata->handle) {
 588                 return;
 589         }
 590         DBG2("Trace UST destroy metadata %d", metadata->handle);
 591         free(metadata);
 592 }
 593
 594 /*
 595  * Iterate over a hash table containing channels and cleanup safely.
 596  */
 597 static void destroy_channels(struct lttng_ht *channels)
 598 {
 599         int ret;
 600         struct lttng_ht_node_str *node;
 601         struct lttng_ht_iter iter;
 602
 603         rcu_read_lock();
 604
 605         cds_lfht_for_each_entry(channels->ht, &iter.iter, node, node) {
 606                 ret = lttng_ht_del(channels, &iter);
 607                 assert(!ret);
 608                 call_rcu(&node->head, destroy_channel_rcu);
 609         }
 610
 611         lttng_ht_destroy(channels);
 612
 613         rcu_read_unlock();
 614 }
 615
 616 /*
 617  * Cleanup UST pid domain.
 618  */
 619 static void destroy_domain_pid(struct lttng_ht *ht)
 620 {
 621         int ret;
 622         struct lttng_ht_iter iter;
 623         struct ltt_ust_domain_pid *dpid;
 624
 625         cds_lfht_for_each_entry(ht->ht, &iter.iter, dpid, node.node) {
 626                 ret = lttng_ht_del(ht , &iter);
 627                 assert(!ret);
 628                 destroy_channels(dpid->channels);
 629         }
 630
 631         lttng_ht_destroy(ht);
 632 }
 633
 634 /*
 635  * Cleanup UST exec name domain.
 636  */
 637 static void destroy_domain_exec(struct lttng_ht *ht)
 638 {
 639         int ret;
 640         struct lttng_ht_iter iter;
 641         struct ltt_ust_domain_exec *dexec;
 642
 643         cds_lfht_for_each_entry(ht->ht, &iter.iter, dexec, node.node) {
 644                 ret = lttng_ht_del(ht , &iter);
 645                 assert(!ret);
 646                 destroy_channels(dexec->channels);
 647         }
 648
 649         lttng_ht_destroy(ht);
 650 }
 651
 652 /*
 653  * Cleanup UST global domain.
 654  */
 655 static void destroy_domain_global(struct ltt_ust_domain_global *dom)
 656 {
 657         destroy_channels(dom->channels);
 658 }
 659
 660 /*
 661  * Cleanup ust session structure
 662  */
 663 void trace_ust_destroy_session(struct ltt_ust_session *session)
 664 {
 665         /* Extra protection */
 666         if (session == NULL) {
 667                 return;
 668         }
 669
 670         rcu_read_lock();
 671
 672         DBG2("Trace UST destroy session %u", session->id);
 673
 674         /* Cleaning up UST domain */
 675         destroy_domain_global(&session->domain_global);
 676         destroy_domain_pid(session->domain_pid);
 677         destroy_domain_exec(session->domain_exec);
 678
 679         consumer_destroy_output(session->consumer);
 680         consumer_destroy_output(session->tmp_consumer);
 681
 682         free(session);
 683
 684         rcu_read_unlock();
 685 }