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, int session_id,
  89                 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         /* Set session path */
 113         ret = snprintf(lus->pathname, PATH_MAX, "%s/ust", path);
 114         if (ret < 0) {
 115                 PERROR("snprintf kernel traces path");
 116                 goto error_free_session;
 117         }
 118
 119         DBG2("UST trace session create successful");
 120
 121         return lus;
 122
 123 error_free_session:
 124         lttng_ht_destroy(lus->domain_global.channels);
 125         lttng_ht_destroy(lus->domain_exec);
 126         lttng_ht_destroy(lus->domain_pid);
 127         free(lus);
 128 error:
 129         return NULL;
 130 }
 131
 132 /*
 133  * Allocate and initialize a ust channel data structure.
 134  *
 135  * Return pointer to structure or NULL.
 136  */
 137 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *chan,
 138                 char *path)
 139 {
 140         int ret;
 141         struct ltt_ust_channel *luc;
 142
 143         luc = zmalloc(sizeof(struct ltt_ust_channel));
 144         if (luc == NULL) {
 145                 PERROR("ltt_ust_channel zmalloc");
 146                 goto error;
 147         }
 148
 149         /* Copy UST channel attributes */
 150         luc->attr.overwrite = chan->attr.overwrite;
 151         luc->attr.subbuf_size = chan->attr.subbuf_size;
 152         luc->attr.num_subbuf = chan->attr.num_subbuf;
 153         luc->attr.switch_timer_interval = chan->attr.switch_timer_interval;
 154         luc->attr.read_timer_interval = chan->attr.read_timer_interval;
 155         luc->attr.output = chan->attr.output;
 156
 157         /* Translate to UST output enum */
 158         switch (luc->attr.output) {
 159         default:
 160                 luc->attr.output = LTTNG_UST_MMAP;
 161                 break;
 162         }
 163
 164         /* Copy channel name */
 165         strncpy(luc->name, chan->name, sizeof(luc->name));
 166         luc->name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
 167
 168         /* Init node */
 169         lttng_ht_node_init_str(&luc->node, luc->name);
 170         /* Alloc hash tables */
 171         luc->events = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
 172         luc->ctx = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
 173
 174         /* Set trace output path */
 175         ret = snprintf(luc->pathname, PATH_MAX, "%s", path);
 176         if (ret < 0) {
 177                 PERROR("asprintf ust create channel");
 178                 goto error_free_channel;
 179         }
 180
 181         DBG2("Trace UST channel %s created", luc->name);
 182
 183         return luc;
 184
 185 error_free_channel:
 186         lttng_ht_destroy(luc->ctx);
 187         lttng_ht_destroy(luc->events);
 188         free(luc);
 189 error:
 190         return NULL;
 191 }
 192
 193 /*
 194  * Allocate and initialize a ust event. Set name and event type.
 195  *
 196  * Return pointer to structure or NULL.
 197  */
 198 struct ltt_ust_event *trace_ust_create_event(struct lttng_event *ev)
 199 {
 200         struct ltt_ust_event *lue;
 201
 202         lue = zmalloc(sizeof(struct ltt_ust_event));
 203         if (lue == NULL) {
 204                 PERROR("ust event zmalloc");
 205                 goto error;
 206         }
 207
 208         switch (ev->type) {
 209         case LTTNG_EVENT_PROBE:
 210                 lue->attr.instrumentation = LTTNG_UST_PROBE;
 211                 break;
 212         case LTTNG_EVENT_FUNCTION:
 213                 lue->attr.instrumentation = LTTNG_UST_FUNCTION;
 214                 break;
 215         case LTTNG_EVENT_FUNCTION_ENTRY:
 216                 lue->attr.instrumentation = LTTNG_UST_FUNCTION;
 217                 break;
 218         case LTTNG_EVENT_TRACEPOINT:
 219                 lue->attr.instrumentation = LTTNG_UST_TRACEPOINT;
 220                 break;
 221         default:
 222                 ERR("Unknown ust instrumentation type (%d)", ev->type);
 223                 goto error_free_event;
 224         }
 225
 226         /* Copy event name */
 227         strncpy(lue->attr.name, ev->name, LTTNG_UST_SYM_NAME_LEN);
 228         lue->attr.name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
 229
 230         switch (ev->loglevel_type) {
 231         case LTTNG_EVENT_LOGLEVEL_ALL:
 232                 lue->attr.loglevel_type = LTTNG_UST_LOGLEVEL_ALL;
 233                 lue->attr.loglevel = -1;        /* Force to -1 */
 234                 break;
 235         case LTTNG_EVENT_LOGLEVEL_RANGE:
 236                 lue->attr.loglevel_type = LTTNG_UST_LOGLEVEL_RANGE;
 237                 lue->attr.loglevel = ev->loglevel;
 238                 break;
 239         case LTTNG_EVENT_LOGLEVEL_SINGLE:
 240                 lue->attr.loglevel_type = LTTNG_UST_LOGLEVEL_SINGLE;
 241                 lue->attr.loglevel = ev->loglevel;
 242                 break;
 243         default:
 244                 ERR("Unknown ust loglevel type (%d)", ev->loglevel_type);
 245                 goto error_free_event;
 246         }
 247
 248
 249         /* Init node */
 250         lttng_ht_node_init_str(&lue->node, lue->attr.name);
 251         /* Alloc context hash tables */
 252         lue->ctx = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
 253
 254         DBG2("Trace UST event %s, loglevel (%d,%d) created",
 255                 lue->attr.name, lue->attr.loglevel_type,
 256                 lue->attr.loglevel);
 257
 258         return lue;
 259
 260 error_free_event:
 261         lttng_ht_destroy(lue->ctx);
 262         free(lue);
 263 error:
 264         return NULL;
 265 }
 266
 267 /*
 268  * Allocate and initialize a ust metadata.
 269  *
 270  * Return pointer to structure or NULL.
 271  */
 272 struct ltt_ust_metadata *trace_ust_create_metadata(char *path)
 273 {
 274         int ret;
 275         struct ltt_ust_metadata *lum;
 276
 277         lum = zmalloc(sizeof(struct ltt_ust_metadata));
 278         if (lum == NULL) {
 279                 PERROR("ust metadata zmalloc");
 280                 goto error;
 281         }
 282
 283         /* Set default attributes */
 284         lum->attr.overwrite = DEFAULT_CHANNEL_OVERWRITE;
 285         lum->attr.subbuf_size = DEFAULT_METADATA_SUBBUF_SIZE;
 286         lum->attr.num_subbuf = DEFAULT_METADATA_SUBBUF_NUM;
 287         lum->attr.switch_timer_interval = DEFAULT_CHANNEL_SWITCH_TIMER;
 288         lum->attr.read_timer_interval = DEFAULT_CHANNEL_READ_TIMER;
 289         lum->attr.output = LTTNG_UST_MMAP;
 290
 291         lum->handle = -1;
 292         /* Set metadata trace path */
 293         ret = snprintf(lum->pathname, PATH_MAX, "%s/metadata", path);
 294         if (ret < 0) {
 295                 PERROR("asprintf ust metadata");
 296                 goto error_free_metadata;
 297         }
 298
 299         return lum;
 300
 301 error_free_metadata:
 302         free(lum);
 303 error:
 304         return NULL;
 305 }
 306
 307 /*
 308  * Allocate and initialize an UST context.
 309  *
 310  * Return pointer to structure or NULL.
 311  */
 312 struct ltt_ust_context *trace_ust_create_context(
 313                 struct lttng_event_context *ctx)
 314 {
 315         struct ltt_ust_context *uctx;
 316         enum lttng_ust_context_type utype;
 317
 318         switch (ctx->ctx) {
 319         case LTTNG_EVENT_CONTEXT_VTID:
 320                 utype = LTTNG_UST_CONTEXT_VTID;
 321                 break;
 322         case LTTNG_EVENT_CONTEXT_VPID:
 323                 utype = LTTNG_UST_CONTEXT_VPID;
 324                 break;
 325         case LTTNG_EVENT_CONTEXT_PTHREAD_ID:
 326                 utype = LTTNG_UST_CONTEXT_PTHREAD_ID;
 327                 break;
 328         case LTTNG_EVENT_CONTEXT_PROCNAME:
 329                 utype = LTTNG_UST_CONTEXT_PROCNAME;
 330                 break;
 331         default:
 332                 ERR("Invalid UST context");
 333                 return NULL;
 334         }
 335
 336         uctx = zmalloc(sizeof(struct ltt_ust_context));
 337         if (uctx == NULL) {
 338                 PERROR("zmalloc ltt_ust_context");
 339                 goto error;
 340         }
 341
 342         uctx->ctx.ctx = utype;
 343         lttng_ht_node_init_ulong(&uctx->node, (unsigned long) uctx->ctx.ctx);
 344
 345         return uctx;
 346
 347 error:
 348         return NULL;
 349 }
 350
 351 /*
 352  * RCU safe free context structure.
 353  */
 354 static void destroy_context_rcu(struct rcu_head *head)
 355 {
 356         struct lttng_ht_node_ulong *node =
 357                 caa_container_of(head, struct lttng_ht_node_ulong, head);
 358         struct ltt_ust_context *ctx =
 359                 caa_container_of(node, struct ltt_ust_context, node);
 360
 361         free(ctx);
 362 }
 363
 364 /*
 365  * Cleanup UST context hash table.
 366  */
 367 static void destroy_contexts(struct lttng_ht *ht)
 368 {
 369         int ret;
 370         struct lttng_ht_node_ulong *node;
 371         struct lttng_ht_iter iter;
 372
 373         cds_lfht_for_each_entry(ht->ht, &iter.iter, node, node) {
 374                 ret = lttng_ht_del(ht, &iter);
 375                 if (!ret) {
 376                         call_rcu(&node->head, destroy_context_rcu);
 377                 }
 378         }
 379
 380         lttng_ht_destroy(ht);
 381 }
 382
 383 /*
 384  * Cleanup ust event structure.
 385  */
 386 void trace_ust_destroy_event(struct ltt_ust_event *event)
 387 {
 388         DBG2("Trace destroy UST event %s", event->attr.name);
 389         destroy_contexts(event->ctx);
 390
 391         free(event);
 392 }
 393
 394 /*
 395  * URCU intermediate call to complete destroy event.
 396  */
 397 static void destroy_event_rcu(struct rcu_head *head)
 398 {
 399         struct lttng_ht_node_str *node =
 400                 caa_container_of(head, struct lttng_ht_node_str, head);
 401         struct ltt_ust_event *event =
 402                 caa_container_of(node, struct ltt_ust_event, node);
 403
 404         trace_ust_destroy_event(event);
 405 }
 406
 407 /*
 408  * Cleanup UST events hashtable.
 409  */
 410 static void destroy_events(struct lttng_ht *events)
 411 {
 412         int ret;
 413         struct lttng_ht_node_str *node;
 414         struct lttng_ht_iter iter;
 415
 416         cds_lfht_for_each_entry(events->ht, &iter.iter, node, node) {
 417                 ret = lttng_ht_del(events, &iter);
 418                 assert(!ret);
 419                 call_rcu(&node->head, destroy_event_rcu);
 420         }
 421
 422         lttng_ht_destroy(events);
 423 }
 424
 425 /*
 426  * Cleanup ust channel structure.
 427  */
 428 void trace_ust_destroy_channel(struct ltt_ust_channel *channel)
 429 {
 430         DBG2("Trace destroy UST channel %s", channel->name);
 431
 432         rcu_read_lock();
 433
 434         /* Destroying all events of the channel */
 435         destroy_events(channel->events);
 436         /* Destroying all context of the channel */
 437         destroy_contexts(channel->ctx);
 438
 439         free(channel);
 440
 441         rcu_read_unlock();
 442 }
 443
 444 /*
 445  * URCU intermediate call to complete destroy channel.
 446  */
 447 static void destroy_channel_rcu(struct rcu_head *head)
 448 {
 449         struct lttng_ht_node_str *node =
 450                 caa_container_of(head, struct lttng_ht_node_str, head);
 451         struct ltt_ust_channel *channel =
 452                 caa_container_of(node, struct ltt_ust_channel, node);
 453
 454         trace_ust_destroy_channel(channel);
 455 }
 456
 457 /*
 458  * Cleanup ust metadata structure.
 459  */
 460 void trace_ust_destroy_metadata(struct ltt_ust_metadata *metadata)
 461 {
 462         if (!metadata->handle) {
 463                 return;
 464         }
 465         DBG2("Trace UST destroy metadata %d", metadata->handle);
 466         free(metadata);
 467 }
 468
 469 /*
 470  * Iterate over a hash table containing channels and cleanup safely.
 471  */
 472 static void destroy_channels(struct lttng_ht *channels)
 473 {
 474         int ret;
 475         struct lttng_ht_node_str *node;
 476         struct lttng_ht_iter iter;
 477
 478         rcu_read_lock();
 479
 480         cds_lfht_for_each_entry(channels->ht, &iter.iter, node, node) {
 481                 ret = lttng_ht_del(channels, &iter);
 482                 assert(!ret);
 483                 call_rcu(&node->head, destroy_channel_rcu);
 484         }
 485
 486         lttng_ht_destroy(channels);
 487
 488         rcu_read_unlock();
 489 }
 490
 491 /*
 492  * Cleanup UST pid domain.
 493  */
 494 static void destroy_domain_pid(struct lttng_ht *ht)
 495 {
 496         int ret;
 497         struct lttng_ht_iter iter;
 498         struct ltt_ust_domain_pid *dpid;
 499
 500         cds_lfht_for_each_entry(ht->ht, &iter.iter, dpid, node.node) {
 501                 ret = lttng_ht_del(ht , &iter);
 502                 assert(!ret);
 503                 destroy_channels(dpid->channels);
 504         }
 505
 506         lttng_ht_destroy(ht);
 507 }
 508
 509 /*
 510  * Cleanup UST exec name domain.
 511  */
 512 static void destroy_domain_exec(struct lttng_ht *ht)
 513 {
 514         int ret;
 515         struct lttng_ht_iter iter;
 516         struct ltt_ust_domain_exec *dexec;
 517
 518         cds_lfht_for_each_entry(ht->ht, &iter.iter, dexec, node.node) {
 519                 ret = lttng_ht_del(ht , &iter);
 520                 assert(!ret);
 521                 destroy_channels(dexec->channels);
 522         }
 523
 524         lttng_ht_destroy(ht);
 525 }
 526
 527 /*
 528  * Cleanup UST global domain.
 529  */
 530 static void destroy_domain_global(struct ltt_ust_domain_global *dom)
 531 {
 532         destroy_channels(dom->channels);
 533 }
 534
 535 /*
 536  * Cleanup ust session structure
 537  */
 538 void trace_ust_destroy_session(struct ltt_ust_session *session)
 539 {
 540         /* Extra protection */
 541         if (session == NULL) {
 542                 return;
 543         }
 544
 545         rcu_read_lock();
 546
 547         DBG2("Trace UST destroy session %d", session->id);
 548
 549         /* Cleaning up UST domain */
 550         destroy_domain_global(&session->domain_global);
 551         destroy_domain_pid(session->domain_pid);
 552         destroy_domain_exec(session->domain_exec);
 553
 554         free(session);
 555
 556         rcu_read_unlock();
 557 }