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 it
   5  * under the terms of the GNU General Public License as published by the Free
   6  * Software Foundation; only version 2 of the License.
   7  *
   8  * This program is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  15  * Place - Suite 330, Boston, MA  02111-1307, 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         free(lus);
 125 error:
 126         return NULL;
 127 }
 128
 129 /*
 130  * Allocate and initialize a ust channel data structure.
 131  *
 132  * Return pointer to structure or NULL.
 133  */
 134 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *chan,
 135                 char *path)
 136 {
 137         int ret;
 138         struct ltt_ust_channel *luc;
 139
 140         luc = zmalloc(sizeof(struct ltt_ust_channel));
 141         if (luc == NULL) {
 142                 perror("ltt_ust_channel zmalloc");
 143                 goto error;
 144         }
 145
 146         /* Copy UST channel attributes */
 147         luc->attr.overwrite = chan->attr.overwrite;
 148         luc->attr.subbuf_size = chan->attr.subbuf_size;
 149         luc->attr.num_subbuf = chan->attr.num_subbuf;
 150         luc->attr.switch_timer_interval = chan->attr.switch_timer_interval;
 151         luc->attr.read_timer_interval = chan->attr.read_timer_interval;
 152         luc->attr.output = chan->attr.output;
 153
 154         /* Translate to UST output enum */
 155         switch (luc->attr.output) {
 156         default:
 157                 luc->attr.output = LTTNG_UST_MMAP;
 158                 break;
 159         }
 160
 161         /* Copy channel name */
 162         strncpy(luc->name, chan->name, sizeof(luc->name));
 163         luc->name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
 164
 165         /* Init node */
 166         lttng_ht_node_init_str(&luc->node, luc->name);
 167         /* Alloc hash tables */
 168         luc->events = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
 169         luc->ctx = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
 170
 171         /* Set trace output path */
 172         ret = snprintf(luc->pathname, PATH_MAX, "%s", path);
 173         if (ret < 0) {
 174                 perror("asprintf ust create channel");
 175                 goto error_free_channel;
 176         }
 177
 178         DBG2("Trace UST channel %s created", luc->name);
 179
 180         return luc;
 181
 182 error_free_channel:
 183         free(luc);
 184 error:
 185         return NULL;
 186 }
 187
 188 /*
 189  * Allocate and initialize a ust event. Set name and event type.
 190  *
 191  * Return pointer to structure or NULL.
 192  */
 193 struct ltt_ust_event *trace_ust_create_event(struct lttng_event *ev)
 194 {
 195         struct ltt_ust_event *lue;
 196
 197         lue = zmalloc(sizeof(struct ltt_ust_event));
 198         if (lue == NULL) {
 199                 PERROR("ust event zmalloc");
 200                 goto error;
 201         }
 202
 203         switch (ev->type) {
 204         case LTTNG_EVENT_PROBE:
 205                 lue->attr.instrumentation = LTTNG_UST_PROBE;
 206                 break;
 207         case LTTNG_EVENT_FUNCTION:
 208                 lue->attr.instrumentation = LTTNG_UST_FUNCTION;
 209                 break;
 210         case LTTNG_EVENT_FUNCTION_ENTRY:
 211                 lue->attr.instrumentation = LTTNG_UST_FUNCTION;
 212                 break;
 213         case LTTNG_EVENT_TRACEPOINT:
 214                 lue->attr.instrumentation = LTTNG_UST_TRACEPOINT;
 215                 break;
 216         default:
 217                 ERR("Unknown ust instrumentation type (%d)", ev->type);
 218                 goto error_free_event;
 219         }
 220
 221         /* Copy event name */
 222         strncpy(lue->attr.name, ev->name, LTTNG_UST_SYM_NAME_LEN);
 223         lue->attr.name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
 224
 225         switch (ev->loglevel_type) {
 226         case LTTNG_EVENT_LOGLEVEL_ALL:
 227                 lue->attr.loglevel_type = LTTNG_UST_LOGLEVEL_ALL;
 228                 break;
 229         case LTTNG_EVENT_LOGLEVEL_RANGE:
 230                 lue->attr.loglevel_type = LTTNG_UST_LOGLEVEL_RANGE;
 231                 break;
 232         case LTTNG_EVENT_LOGLEVEL_SINGLE:
 233                 lue->attr.loglevel_type = LTTNG_UST_LOGLEVEL_SINGLE;
 234                 break;
 235         default:
 236                 ERR("Unknown ust loglevel type (%d)", ev->type);
 237                 goto error_free_event;
 238         }
 239
 240         /* Copy loglevel */
 241         lue->attr.loglevel = ev->loglevel;
 242
 243         /* Init node */
 244         lttng_ht_node_init_str(&lue->node, lue->attr.name);
 245         /* Alloc context hash tables */
 246         lue->ctx = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
 247
 248         DBG2("Trace UST event %s created", lue->attr.name);
 249
 250         return lue;
 251
 252 error_free_event:
 253         free(lue);
 254 error:
 255         return NULL;
 256 }
 257
 258 /*
 259  * Allocate and initialize a ust metadata.
 260  *
 261  * Return pointer to structure or NULL.
 262  */
 263 struct ltt_ust_metadata *trace_ust_create_metadata(char *path)
 264 {
 265         int ret;
 266         struct ltt_ust_metadata *lum;
 267
 268         lum = zmalloc(sizeof(struct ltt_ust_metadata));
 269         if (lum == NULL) {
 270                 perror("ust metadata zmalloc");
 271                 goto error;
 272         }
 273
 274         /* Set default attributes */
 275         lum->attr.overwrite = DEFAULT_CHANNEL_OVERWRITE;
 276         lum->attr.subbuf_size = DEFAULT_METADATA_SUBBUF_SIZE;
 277         lum->attr.num_subbuf = DEFAULT_METADATA_SUBBUF_NUM;
 278         lum->attr.switch_timer_interval = DEFAULT_CHANNEL_SWITCH_TIMER;
 279         lum->attr.read_timer_interval = DEFAULT_CHANNEL_READ_TIMER;
 280         lum->attr.output = LTTNG_UST_MMAP;
 281
 282         lum->handle = -1;
 283         /* Set metadata trace path */
 284         ret = snprintf(lum->pathname, PATH_MAX, "%s/metadata", path);
 285         if (ret < 0) {
 286                 perror("asprintf ust metadata");
 287                 goto error_free_metadata;
 288         }
 289
 290         return lum;
 291
 292 error_free_metadata:
 293         free(lum);
 294 error:
 295         return NULL;
 296 }
 297
 298 /*
 299  * Allocate and initialize an UST context.
 300  *
 301  * Return pointer to structure or NULL.
 302  */
 303 struct ltt_ust_context *trace_ust_create_context(
 304                 struct lttng_event_context *ctx)
 305 {
 306         struct ltt_ust_context *uctx;
 307         enum lttng_ust_context_type utype;
 308
 309         switch (ctx->ctx) {
 310         case LTTNG_EVENT_CONTEXT_VTID:
 311                 utype = LTTNG_UST_CONTEXT_VTID;
 312                 break;
 313         case LTTNG_EVENT_CONTEXT_VPID:
 314                 utype = LTTNG_UST_CONTEXT_VPID;
 315                 break;
 316         case LTTNG_EVENT_CONTEXT_PTHREAD_ID:
 317                 utype = LTTNG_UST_CONTEXT_PTHREAD_ID;
 318                 break;
 319         case LTTNG_EVENT_CONTEXT_PROCNAME:
 320                 utype = LTTNG_UST_CONTEXT_PROCNAME;
 321                 break;
 322         default:
 323                 ERR("Invalid UST context");
 324                 return NULL;
 325         }
 326
 327         uctx = zmalloc(sizeof(struct ltt_ust_context));
 328         if (uctx == NULL) {
 329                 PERROR("zmalloc ltt_ust_context");
 330                 goto error;
 331         }
 332
 333         uctx->ctx.ctx = utype;
 334         lttng_ht_node_init_ulong(&uctx->node, (unsigned long) uctx->ctx.ctx);
 335
 336         return uctx;
 337
 338 error:
 339         return NULL;
 340 }
 341
 342 /*
 343  * RCU safe free context structure.
 344  */
 345 static void destroy_context_rcu(struct rcu_head *head)
 346 {
 347         struct lttng_ht_node_ulong *node =
 348                 caa_container_of(head, struct lttng_ht_node_ulong, head);
 349         struct ltt_ust_context *ctx =
 350                 caa_container_of(node, struct ltt_ust_context, node);
 351
 352         free(ctx);
 353 }
 354
 355 /*
 356  * Cleanup UST context hash table.
 357  */
 358 static void destroy_contexts(struct lttng_ht *ht)
 359 {
 360         int ret;
 361         struct lttng_ht_node_ulong *node;
 362         struct lttng_ht_iter iter;
 363
 364         cds_lfht_for_each_entry(ht->ht, &iter.iter, node, node) {
 365                 ret = lttng_ht_del(ht, &iter);
 366                 if (!ret) {
 367                         call_rcu(&node->head, destroy_context_rcu);
 368                 }
 369         }
 370
 371         lttng_ht_destroy(ht);
 372 }
 373
 374 /*
 375  * Cleanup ust event structure.
 376  */
 377 void trace_ust_destroy_event(struct ltt_ust_event *event)
 378 {
 379         DBG2("Trace destroy UST event %s", event->attr.name);
 380         destroy_contexts(event->ctx);
 381
 382         free(event);
 383 }
 384
 385 /*
 386  * URCU intermediate call to complete destroy event.
 387  */
 388 static void destroy_event_rcu(struct rcu_head *head)
 389 {
 390         struct lttng_ht_node_str *node =
 391                 caa_container_of(head, struct lttng_ht_node_str, head);
 392         struct ltt_ust_event *event =
 393                 caa_container_of(node, struct ltt_ust_event, node);
 394
 395         trace_ust_destroy_event(event);
 396 }
 397
 398 /*
 399  * Cleanup UST events hashtable.
 400  */
 401 static void destroy_events(struct lttng_ht *events)
 402 {
 403         int ret;
 404         struct lttng_ht_node_str *node;
 405         struct lttng_ht_iter iter;
 406
 407         cds_lfht_for_each_entry(events->ht, &iter.iter, node, node) {
 408                 ret = lttng_ht_del(events, &iter);
 409                 assert(!ret);
 410                 call_rcu(&node->head, destroy_event_rcu);
 411         }
 412
 413         lttng_ht_destroy(events);
 414 }
 415
 416 /*
 417  * Cleanup ust channel structure.
 418  */
 419 void trace_ust_destroy_channel(struct ltt_ust_channel *channel)
 420 {
 421         DBG2("Trace destroy UST channel %s", channel->name);
 422
 423         rcu_read_lock();
 424
 425         /* Destroying all events of the channel */
 426         destroy_events(channel->events);
 427         /* Destroying all context of the channel */
 428         destroy_contexts(channel->ctx);
 429
 430         free(channel);
 431
 432         rcu_read_unlock();
 433 }
 434
 435 /*
 436  * URCU intermediate call to complete destroy channel.
 437  */
 438 static void destroy_channel_rcu(struct rcu_head *head)
 439 {
 440         struct lttng_ht_node_str *node =
 441                 caa_container_of(head, struct lttng_ht_node_str, head);
 442         struct ltt_ust_channel *channel =
 443                 caa_container_of(node, struct ltt_ust_channel, node);
 444
 445         trace_ust_destroy_channel(channel);
 446 }
 447
 448 /*
 449  * Cleanup ust metadata structure.
 450  */
 451 void trace_ust_destroy_metadata(struct ltt_ust_metadata *metadata)
 452 {
 453         DBG2("Trace UST destroy metadata %d", metadata->handle);
 454
 455         free(metadata);
 456 }
 457
 458 /*
 459  * Iterate over a hash table containing channels and cleanup safely.
 460  */
 461 static void destroy_channels(struct lttng_ht *channels)
 462 {
 463         int ret;
 464         struct lttng_ht_node_str *node;
 465         struct lttng_ht_iter iter;
 466
 467         rcu_read_lock();
 468
 469         cds_lfht_for_each_entry(channels->ht, &iter.iter, node, node) {
 470                 ret = lttng_ht_del(channels, &iter);
 471                 assert(!ret);
 472                 call_rcu(&node->head, destroy_channel_rcu);
 473         }
 474
 475         lttng_ht_destroy(channels);
 476
 477         rcu_read_unlock();
 478 }
 479
 480 /*
 481  * Cleanup UST pid domain.
 482  */
 483 static void destroy_domain_pid(struct lttng_ht *ht)
 484 {
 485         int ret;
 486         struct lttng_ht_iter iter;
 487         struct ltt_ust_domain_pid *dpid;
 488
 489         cds_lfht_for_each_entry(ht->ht, &iter.iter, dpid, node.node) {
 490                 ret = lttng_ht_del(ht , &iter);
 491                 assert(!ret);
 492                 destroy_channels(dpid->channels);
 493         }
 494
 495         lttng_ht_destroy(ht);
 496 }
 497
 498 /*
 499  * Cleanup UST exec name domain.
 500  */
 501 static void destroy_domain_exec(struct lttng_ht *ht)
 502 {
 503         int ret;
 504         struct lttng_ht_iter iter;
 505         struct ltt_ust_domain_exec *dexec;
 506
 507         cds_lfht_for_each_entry(ht->ht, &iter.iter, dexec, node.node) {
 508                 ret = lttng_ht_del(ht , &iter);
 509                 assert(!ret);
 510                 destroy_channels(dexec->channels);
 511         }
 512
 513         lttng_ht_destroy(ht);
 514 }
 515
 516 /*
 517  * Cleanup UST global domain.
 518  */
 519 static void destroy_domain_global(struct ltt_ust_domain_global *dom)
 520 {
 521         destroy_channels(dom->channels);
 522 }
 523
 524 /*
 525  * Cleanup ust session structure
 526  */
 527 void trace_ust_destroy_session(struct ltt_ust_session *session)
 528 {
 529         /* Extra protection */
 530         if (session == NULL) {
 531                 return;
 532         }
 533
 534         rcu_read_lock();
 535
 536         DBG2("Trace UST destroy session %d", session->id);
 537
 538         /* Cleaning up UST domain */
 539         destroy_domain_global(&session->domain_global);
 540         destroy_domain_pid(session->domain_pid);
 541         destroy_domain_exec(session->domain_exec);
 542
 543         free(session);
 544
 545         rcu_read_unlock();
 546 }