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