Implement consumer ring buffer position sampling
[lttng-tools.git] / src / bin / lttng-sessiond / trace-ust.c
1 /*
2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
3 * Copyright (C) 2016 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License, version 2 only,
7 * as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
17 */
18
19 #define _LGPL_SOURCE
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <string.h>
23 #include <unistd.h>
24 #include <inttypes.h>
25
26 #include <common/common.h>
27 #include <common/defaults.h>
28
29 #include "buffer-registry.h"
30 #include "trace-ust.h"
31 #include "utils.h"
32 #include "ust-app.h"
33 #include "agent.h"
34
35 /*
36 * Match function for the events hash table lookup.
37 *
38 * Matches by name only. Used by the disable command.
39 */
40 int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
41 const void *_key)
42 {
43 struct ltt_ust_event *event;
44 const char *name;
45
46 assert(node);
47 assert(_key);
48
49 event = caa_container_of(node, struct ltt_ust_event, node.node);
50 name = _key;
51
52 /* Event name */
53 if (strncmp(event->attr.name, name, sizeof(event->attr.name)) != 0) {
54 goto no_match;
55 }
56
57 /* Match */
58 return 1;
59
60 no_match:
61 return 0;
62 }
63
64 /*
65 * Match function for the hash table lookup.
66 *
67 * It matches an ust event based on three attributes which are the event name,
68 * the filter bytecode and the loglevel.
69 */
70 int trace_ust_ht_match_event(struct cds_lfht_node *node, const void *_key)
71 {
72 struct ltt_ust_event *event;
73 const struct ltt_ust_ht_key *key;
74 int ev_loglevel_value;
75 int ll_match;
76
77 assert(node);
78 assert(_key);
79
80 event = caa_container_of(node, struct ltt_ust_event, node.node);
81 key = _key;
82 ev_loglevel_value = event->attr.loglevel;
83
84 /* Match the 4 elements of the key: name, filter, loglevel, exclusions. */
85
86 /* Event name */
87 if (strncmp(event->attr.name, key->name, sizeof(event->attr.name)) != 0) {
88 goto no_match;
89 }
90
91 /* Event loglevel value and type. */
92 ll_match = loglevels_match(event->attr.loglevel_type,
93 ev_loglevel_value, key->loglevel_type,
94 key->loglevel_value, LTTNG_UST_LOGLEVEL_ALL);
95
96 if (!ll_match) {
97 goto no_match;
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 /* If only one of the exclusions is NULL, fail. */
115 if ((key->exclusion && !event->exclusion) || (!key->exclusion && event->exclusion)) {
116 goto no_match;
117 }
118
119 if (key->exclusion && event->exclusion) {
120 size_t i;
121
122 /* Check exclusion counts first. */
123 if (event->exclusion->count != key->exclusion->count) {
124 goto no_match;
125 }
126
127 /* Compare names individually. */
128 for (i = 0; i < event->exclusion->count; ++i) {
129 size_t j;
130 bool found = false;
131 const char *name_ev =
132 LTTNG_EVENT_EXCLUSION_NAME_AT(
133 event->exclusion, i);
134
135 /*
136 * Compare this exclusion name to all the key's
137 * exclusion names.
138 */
139 for (j = 0; j < key->exclusion->count; ++j) {
140 const char *name_key =
141 LTTNG_EVENT_EXCLUSION_NAME_AT(
142 key->exclusion, j);
143
144 if (!strncmp(name_ev, name_key,
145 LTTNG_SYMBOL_NAME_LEN)) {
146 /* Names match! */
147 found = true;
148 break;
149 }
150 }
151
152 /*
153 * If the current exclusion name was not found amongst
154 * the key's exclusion names, then there's no match.
155 */
156 if (!found) {
157 goto no_match;
158 }
159 }
160 }
161 /* Match. */
162 return 1;
163
164 no_match:
165 return 0;
166 }
167
168 /*
169 * Find the channel in the hashtable and return channel pointer. RCU read side
170 * lock MUST be acquired before calling this.
171 */
172 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
173 char *name)
174 {
175 struct lttng_ht_node_str *node;
176 struct lttng_ht_iter iter;
177
178 /*
179 * If we receive an empty string for channel name, it means the
180 * default channel name is requested.
181 */
182 if (name[0] == '\0')
183 name = DEFAULT_CHANNEL_NAME;
184
185 lttng_ht_lookup(ht, (void *)name, &iter);
186 node = lttng_ht_iter_get_node_str(&iter);
187 if (node == NULL) {
188 goto error;
189 }
190
191 DBG2("Trace UST channel %s found by name", name);
192
193 return caa_container_of(node, struct ltt_ust_channel, node);
194
195 error:
196 DBG2("Trace UST channel %s not found by name", name);
197 return NULL;
198 }
199
200 /*
201 * Find the event in the hashtable and return event pointer. RCU read side lock
202 * MUST be acquired before calling this.
203 */
204 struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
205 char *name, struct lttng_filter_bytecode *filter,
206 enum lttng_ust_loglevel_type loglevel_type, int loglevel_value,
207 struct lttng_event_exclusion *exclusion)
208 {
209 struct lttng_ht_node_str *node;
210 struct lttng_ht_iter iter;
211 struct ltt_ust_ht_key key;
212
213 assert(name);
214 assert(ht);
215
216 key.name = name;
217 key.filter = filter;
218 key.loglevel_type = loglevel_type;
219 key.loglevel_value = loglevel_value;
220 key.exclusion = exclusion;
221
222 cds_lfht_lookup(ht->ht, ht->hash_fct((void *) name, lttng_ht_seed),
223 trace_ust_ht_match_event, &key, &iter.iter);
224 node = lttng_ht_iter_get_node_str(&iter);
225 if (node == NULL) {
226 goto error;
227 }
228
229 DBG2("Trace UST event %s found", key.name);
230
231 return caa_container_of(node, struct ltt_ust_event, node);
232
233 error:
234 DBG2("Trace UST event %s NOT found", key.name);
235 return NULL;
236 }
237
238 /*
239 * Lookup an agent in the session agents hash table by domain type and return
240 * the object if found else NULL.
241 *
242 * RCU read side lock must be acquired before calling and only released
243 * once the agent is no longer in scope or being used.
244 */
245 struct agent *trace_ust_find_agent(struct ltt_ust_session *session,
246 enum lttng_domain_type domain_type)
247 {
248 struct agent *agt = NULL;
249 struct lttng_ht_node_u64 *node;
250 struct lttng_ht_iter iter;
251 uint64_t key;
252
253 assert(session);
254
255 DBG3("Trace ust agent lookup for domain %d", domain_type);
256
257 key = domain_type;
258
259 lttng_ht_lookup(session->agents, &key, &iter);
260 node = lttng_ht_iter_get_node_u64(&iter);
261 if (!node) {
262 goto end;
263 }
264 agt = caa_container_of(node, struct agent, node);
265
266 end:
267 return agt;
268 }
269
270 /*
271 * Allocate and initialize a ust session data structure.
272 *
273 * Return pointer to structure or NULL.
274 */
275 struct ltt_ust_session *trace_ust_create_session(uint64_t session_id)
276 {
277 struct ltt_ust_session *lus;
278
279 /* Allocate a new ltt ust session */
280 lus = zmalloc(sizeof(struct ltt_ust_session));
281 if (lus == NULL) {
282 PERROR("create ust session zmalloc");
283 goto error;
284 }
285
286 /* Init data structure */
287 lus->id = session_id;
288 lus->active = 0;
289
290 /* Set default metadata channel attribute. */
291 lus->metadata_attr.overwrite = DEFAULT_CHANNEL_OVERWRITE;
292 lus->metadata_attr.subbuf_size = default_get_metadata_subbuf_size();
293 lus->metadata_attr.num_subbuf = DEFAULT_METADATA_SUBBUF_NUM;
294 lus->metadata_attr.switch_timer_interval = DEFAULT_METADATA_SWITCH_TIMER;
295 lus->metadata_attr.read_timer_interval = DEFAULT_METADATA_READ_TIMER;
296 lus->metadata_attr.output = LTTNG_UST_MMAP;
297
298 /*
299 * Default buffer type. This can be changed through an enable channel
300 * requesting a different type. Note that this can only be changed once
301 * during the session lifetime which is at the first enable channel and
302 * only before start. The flag buffer_type_changed indicates the status.
303 */
304 lus->buffer_type = LTTNG_BUFFER_PER_UID;
305 /* Once set to 1, the buffer_type is immutable for the session. */
306 lus->buffer_type_changed = 0;
307 /* Init it in case it get used after allocation. */
308 CDS_INIT_LIST_HEAD(&lus->buffer_reg_uid_list);
309
310 /* Alloc UST global domain channels' HT */
311 lus->domain_global.channels = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
312 /* Alloc agent hash table. */
313 lus->agents = lttng_ht_new(0, LTTNG_HT_TYPE_U64);
314
315 lus->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
316 if (lus->consumer == NULL) {
317 goto error_consumer;
318 }
319
320 DBG2("UST trace session create successful");
321
322 return lus;
323
324 error_consumer:
325 ht_cleanup_push(lus->domain_global.channels);
326 ht_cleanup_push(lus->agents);
327 free(lus);
328 error:
329 return NULL;
330 }
331
332 /*
333 * Allocate and initialize a ust channel data structure.
334 *
335 * Return pointer to structure or NULL.
336 */
337 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *chan,
338 enum lttng_domain_type domain)
339 {
340 struct ltt_ust_channel *luc;
341
342 assert(chan);
343
344 luc = zmalloc(sizeof(struct ltt_ust_channel));
345 if (luc == NULL) {
346 PERROR("ltt_ust_channel zmalloc");
347 goto error;
348 }
349
350 luc->domain = domain;
351
352 /* Copy UST channel attributes */
353 luc->attr.overwrite = chan->attr.overwrite;
354 luc->attr.subbuf_size = chan->attr.subbuf_size;
355 luc->attr.num_subbuf = chan->attr.num_subbuf;
356 luc->attr.switch_timer_interval = chan->attr.switch_timer_interval;
357 luc->attr.read_timer_interval = chan->attr.read_timer_interval;
358 luc->attr.output = (enum lttng_ust_output) chan->attr.output;
359 luc->monitor_timer_interval =
360 ((struct lttng_channel_extended *) chan->attr.extended.ptr)->monitor_timer_interval;
361
362 /* Translate to UST output enum */
363 switch (luc->attr.output) {
364 default:
365 luc->attr.output = LTTNG_UST_MMAP;
366 break;
367 }
368
369 /*
370 * If we receive an empty string for channel name, it means the
371 * default channel name is requested.
372 */
373 if (chan->name[0] == '\0') {
374 strncpy(luc->name, DEFAULT_CHANNEL_NAME, sizeof(luc->name));
375 } else {
376 /* Copy channel name */
377 strncpy(luc->name, chan->name, sizeof(luc->name));
378 }
379 luc->name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
380
381 /* Init node */
382 lttng_ht_node_init_str(&luc->node, luc->name);
383 CDS_INIT_LIST_HEAD(&luc->ctx_list);
384
385 /* Alloc hash tables */
386 luc->events = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
387 luc->ctx = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
388
389 /* On-disk circular buffer parameters */
390 luc->tracefile_size = chan->attr.tracefile_size;
391 luc->tracefile_count = chan->attr.tracefile_count;
392
393 DBG2("Trace UST channel %s created", luc->name);
394
395 error:
396 return luc;
397 }
398
399 /*
400 * Validates an exclusion list.
401 *
402 * Returns 0 if valid, negative value if invalid.
403 */
404 static int validate_exclusion(struct lttng_event_exclusion *exclusion)
405 {
406 size_t i;
407 int ret = 0;
408
409 assert(exclusion);
410
411 for (i = 0; i < exclusion->count; ++i) {
412 size_t j;
413 const char *name_a =
414 LTTNG_EVENT_EXCLUSION_NAME_AT(exclusion, i);
415
416 for (j = 0; j < i; ++j) {
417 const char *name_b =
418 LTTNG_EVENT_EXCLUSION_NAME_AT(exclusion, j);
419
420 if (!strncmp(name_a, name_b, LTTNG_SYMBOL_NAME_LEN)) {
421 /* Match! */
422 ret = -1;
423 goto end;
424 }
425 }
426 }
427
428 end:
429 return ret;
430 }
431
432 /*
433 * Allocate and initialize a ust event. Set name and event type.
434 * We own filter_expression, filter, and exclusion.
435 *
436 * Return pointer to structure or NULL.
437 */
438 struct ltt_ust_event *trace_ust_create_event(struct lttng_event *ev,
439 char *filter_expression,
440 struct lttng_filter_bytecode *filter,
441 struct lttng_event_exclusion *exclusion,
442 bool internal_event)
443 {
444 struct ltt_ust_event *lue;
445
446 assert(ev);
447
448 if (exclusion && validate_exclusion(exclusion)) {
449 goto error;
450 }
451
452 lue = zmalloc(sizeof(struct ltt_ust_event));
453 if (lue == NULL) {
454 PERROR("ust event zmalloc");
455 goto error;
456 }
457
458 lue->internal = internal_event;
459
460 switch (ev->type) {
461 case LTTNG_EVENT_PROBE:
462 lue->attr.instrumentation = LTTNG_UST_PROBE;
463 break;
464 case LTTNG_EVENT_FUNCTION:
465 lue->attr.instrumentation = LTTNG_UST_FUNCTION;
466 break;
467 case LTTNG_EVENT_FUNCTION_ENTRY:
468 lue->attr.instrumentation = LTTNG_UST_FUNCTION;
469 break;
470 case LTTNG_EVENT_TRACEPOINT:
471 lue->attr.instrumentation = LTTNG_UST_TRACEPOINT;
472 break;
473 default:
474 ERR("Unknown ust instrumentation type (%d)", ev->type);
475 goto error_free_event;
476 }
477
478 /* Copy event name */
479 strncpy(lue->attr.name, ev->name, LTTNG_UST_SYM_NAME_LEN);
480 lue->attr.name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
481
482 switch (ev->loglevel_type) {
483 case LTTNG_EVENT_LOGLEVEL_ALL:
484 lue->attr.loglevel_type = LTTNG_UST_LOGLEVEL_ALL;
485 lue->attr.loglevel = -1; /* Force to -1 */
486 break;
487 case LTTNG_EVENT_LOGLEVEL_RANGE:
488 lue->attr.loglevel_type = LTTNG_UST_LOGLEVEL_RANGE;
489 lue->attr.loglevel = ev->loglevel;
490 break;
491 case LTTNG_EVENT_LOGLEVEL_SINGLE:
492 lue->attr.loglevel_type = LTTNG_UST_LOGLEVEL_SINGLE;
493 lue->attr.loglevel = ev->loglevel;
494 break;
495 default:
496 ERR("Unknown ust loglevel type (%d)", ev->loglevel_type);
497 goto error_free_event;
498 }
499
500 /* Same layout. */
501 lue->filter_expression = filter_expression;
502 lue->filter = filter;
503 lue->exclusion = exclusion;
504
505 /* Init node */
506 lttng_ht_node_init_str(&lue->node, lue->attr.name);
507
508 DBG2("Trace UST event %s, loglevel (%d,%d) created",
509 lue->attr.name, lue->attr.loglevel_type,
510 lue->attr.loglevel);
511
512 return lue;
513
514 error_free_event:
515 free(lue);
516 error:
517 free(filter_expression);
518 free(filter);
519 free(exclusion);
520 return NULL;
521 }
522
523 static
524 int trace_ust_context_type_event_to_ust(
525 enum lttng_event_context_type type)
526 {
527 int utype;
528
529 switch (type) {
530 case LTTNG_EVENT_CONTEXT_VTID:
531 utype = LTTNG_UST_CONTEXT_VTID;
532 break;
533 case LTTNG_EVENT_CONTEXT_VPID:
534 utype = LTTNG_UST_CONTEXT_VPID;
535 break;
536 case LTTNG_EVENT_CONTEXT_PTHREAD_ID:
537 utype = LTTNG_UST_CONTEXT_PTHREAD_ID;
538 break;
539 case LTTNG_EVENT_CONTEXT_PROCNAME:
540 utype = LTTNG_UST_CONTEXT_PROCNAME;
541 break;
542 case LTTNG_EVENT_CONTEXT_IP:
543 utype = LTTNG_UST_CONTEXT_IP;
544 break;
545 case LTTNG_EVENT_CONTEXT_PERF_THREAD_COUNTER:
546 if (!ustctl_has_perf_counters()) {
547 utype = -1;
548 WARN("Perf counters not implemented in UST");
549 } else {
550 utype = LTTNG_UST_CONTEXT_PERF_THREAD_COUNTER;
551 }
552 break;
553 case LTTNG_EVENT_CONTEXT_APP_CONTEXT:
554 utype = LTTNG_UST_CONTEXT_APP_CONTEXT;
555 break;
556 default:
557 utype = -1;
558 break;
559 }
560 return utype;
561 }
562
563 /*
564 * Return 1 if contexts match, 0 otherwise.
565 */
566 int trace_ust_match_context(struct ltt_ust_context *uctx,
567 struct lttng_event_context *ctx)
568 {
569 int utype;
570
571 utype = trace_ust_context_type_event_to_ust(ctx->ctx);
572 if (utype < 0) {
573 return 0;
574 }
575 if (uctx->ctx.ctx != utype) {
576 return 0;
577 }
578 switch (utype) {
579 case LTTNG_UST_CONTEXT_PERF_THREAD_COUNTER:
580 if (uctx->ctx.u.perf_counter.type
581 != ctx->u.perf_counter.type) {
582 return 0;
583 }
584 if (uctx->ctx.u.perf_counter.config
585 != ctx->u.perf_counter.config) {
586 return 0;
587 }
588 if (strncmp(uctx->ctx.u.perf_counter.name,
589 ctx->u.perf_counter.name,
590 LTTNG_UST_SYM_NAME_LEN)) {
591 return 0;
592 }
593 break;
594 case LTTNG_UST_CONTEXT_APP_CONTEXT:
595 assert(uctx->ctx.u.app_ctx.provider_name);
596 assert(uctx->ctx.u.app_ctx.ctx_name);
597 if (strcmp(uctx->ctx.u.app_ctx.provider_name,
598 ctx->u.app_ctx.provider_name) ||
599 strcmp(uctx->ctx.u.app_ctx.ctx_name,
600 ctx->u.app_ctx.ctx_name)) {
601 return 0;
602 }
603 default:
604 break;
605
606 }
607 return 1;
608 }
609
610 /*
611 * Allocate and initialize an UST context.
612 *
613 * Return pointer to structure or NULL.
614 */
615 struct ltt_ust_context *trace_ust_create_context(
616 struct lttng_event_context *ctx)
617 {
618 struct ltt_ust_context *uctx = NULL;
619 int utype;
620
621 assert(ctx);
622
623 utype = trace_ust_context_type_event_to_ust(ctx->ctx);
624 if (utype < 0) {
625 ERR("Invalid UST context");
626 goto end;
627 }
628
629 uctx = zmalloc(sizeof(struct ltt_ust_context));
630 if (!uctx) {
631 PERROR("zmalloc ltt_ust_context");
632 goto end;
633 }
634
635 uctx->ctx.ctx = (enum lttng_ust_context_type) utype;
636 switch (utype) {
637 case LTTNG_UST_CONTEXT_PERF_THREAD_COUNTER:
638 uctx->ctx.u.perf_counter.type = ctx->u.perf_counter.type;
639 uctx->ctx.u.perf_counter.config = ctx->u.perf_counter.config;
640 strncpy(uctx->ctx.u.perf_counter.name, ctx->u.perf_counter.name,
641 LTTNG_UST_SYM_NAME_LEN);
642 uctx->ctx.u.perf_counter.name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
643 break;
644 case LTTNG_UST_CONTEXT_APP_CONTEXT:
645 {
646 char *provider_name = NULL, *ctx_name = NULL;
647
648 provider_name = strdup(ctx->u.app_ctx.provider_name);
649 if (!provider_name) {
650 goto error;
651 }
652 uctx->ctx.u.app_ctx.provider_name = provider_name;
653
654 ctx_name = strdup(ctx->u.app_ctx.ctx_name);
655 if (!ctx_name) {
656 goto error;
657 }
658 uctx->ctx.u.app_ctx.ctx_name = ctx_name;
659 break;
660 }
661 default:
662 break;
663 }
664 lttng_ht_node_init_ulong(&uctx->node, (unsigned long) uctx->ctx.ctx);
665 end:
666 return uctx;
667 error:
668 trace_ust_destroy_context(uctx);
669 return NULL;
670 }
671
672 static
673 void destroy_pid_tracker_node_rcu(struct rcu_head *head)
674 {
675 struct ust_pid_tracker_node *tracker_node =
676 caa_container_of(head, struct ust_pid_tracker_node, node.head);
677 free(tracker_node);
678 }
679
680 static
681 void destroy_pid_tracker_node(struct ust_pid_tracker_node *tracker_node)
682 {
683
684 call_rcu(&tracker_node->node.head, destroy_pid_tracker_node_rcu);
685 }
686
687 static
688 int init_pid_tracker(struct ust_pid_tracker *pid_tracker)
689 {
690 int ret = 0;
691
692 pid_tracker->ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
693 if (!pid_tracker->ht) {
694 ret = -1;
695 goto end;
696 }
697
698 end:
699 return ret;
700 }
701
702 /*
703 * Teardown pid tracker content, but don't free pid_tracker object.
704 */
705 static
706 void fini_pid_tracker(struct ust_pid_tracker *pid_tracker)
707 {
708 struct ust_pid_tracker_node *tracker_node;
709 struct lttng_ht_iter iter;
710
711 if (!pid_tracker->ht) {
712 return;
713 }
714 rcu_read_lock();
715 cds_lfht_for_each_entry(pid_tracker->ht->ht,
716 &iter.iter, tracker_node, node.node) {
717 int ret = lttng_ht_del(pid_tracker->ht, &iter);
718
719 assert(!ret);
720 destroy_pid_tracker_node(tracker_node);
721 }
722 rcu_read_unlock();
723 ht_cleanup_push(pid_tracker->ht);
724 pid_tracker->ht = NULL;
725 }
726
727 static
728 struct ust_pid_tracker_node *pid_tracker_lookup(
729 struct ust_pid_tracker *pid_tracker, int pid,
730 struct lttng_ht_iter *iter)
731 {
732 unsigned long _pid = (unsigned long) pid;
733 struct lttng_ht_node_ulong *node;
734
735 lttng_ht_lookup(pid_tracker->ht, (void *) _pid, iter);
736 node = lttng_ht_iter_get_node_ulong(iter);
737 if (node) {
738 return caa_container_of(node, struct ust_pid_tracker_node,
739 node);
740 } else {
741 return NULL;
742 }
743 }
744
745 static
746 int pid_tracker_add_pid(struct ust_pid_tracker *pid_tracker, int pid)
747 {
748 int retval = LTTNG_OK;
749 struct ust_pid_tracker_node *tracker_node;
750 struct lttng_ht_iter iter;
751
752 if (pid < 0) {
753 retval = LTTNG_ERR_INVALID;
754 goto end;
755 }
756 tracker_node = pid_tracker_lookup(pid_tracker, pid, &iter);
757 if (tracker_node) {
758 /* Already exists. */
759 retval = LTTNG_ERR_PID_TRACKED;
760 goto end;
761 }
762 tracker_node = zmalloc(sizeof(*tracker_node));
763 if (!tracker_node) {
764 retval = LTTNG_ERR_NOMEM;
765 goto end;
766 }
767 lttng_ht_node_init_ulong(&tracker_node->node, (unsigned long) pid);
768 lttng_ht_add_unique_ulong(pid_tracker->ht, &tracker_node->node);
769 end:
770 return retval;
771 }
772
773 static
774 int pid_tracker_del_pid(struct ust_pid_tracker *pid_tracker, int pid)
775 {
776 int retval = LTTNG_OK, ret;
777 struct ust_pid_tracker_node *tracker_node;
778 struct lttng_ht_iter iter;
779
780 if (pid < 0) {
781 retval = LTTNG_ERR_INVALID;
782 goto end;
783 }
784 tracker_node = pid_tracker_lookup(pid_tracker, pid, &iter);
785 if (!tracker_node) {
786 /* Not found */
787 retval = LTTNG_ERR_PID_NOT_TRACKED;
788 goto end;
789 }
790 ret = lttng_ht_del(pid_tracker->ht, &iter);
791 assert(!ret);
792
793 destroy_pid_tracker_node(tracker_node);
794 end:
795 return retval;
796 }
797
798 /*
799 * The session lock is held when calling this function.
800 */
801 int trace_ust_pid_tracker_lookup(struct ltt_ust_session *session, int pid)
802 {
803 struct lttng_ht_iter iter;
804
805 if (!session->pid_tracker.ht) {
806 return 1;
807 }
808 if (pid_tracker_lookup(&session->pid_tracker, pid, &iter)) {
809 return 1;
810 }
811 return 0;
812 }
813
814 /*
815 * Called with the session lock held.
816 */
817 int trace_ust_track_pid(struct ltt_ust_session *session, int pid)
818 {
819 int retval = LTTNG_OK;
820
821 if (pid == -1) {
822 /* Track all pids: destroy tracker if exists. */
823 if (session->pid_tracker.ht) {
824 fini_pid_tracker(&session->pid_tracker);
825 /* Ensure all apps have session. */
826 ust_app_global_update_all(session);
827 }
828 } else {
829 int ret;
830
831 if (!session->pid_tracker.ht) {
832 /* Create tracker. */
833 if (init_pid_tracker(&session->pid_tracker)) {
834 ERR("Error initializing PID tracker");
835 retval = LTTNG_ERR_NOMEM;
836 goto end;
837 }
838 ret = pid_tracker_add_pid(&session->pid_tracker, pid);
839 if (ret != LTTNG_OK) {
840 retval = ret;
841 fini_pid_tracker(&session->pid_tracker);
842 goto end;
843 }
844 /* Remove all apps from session except pid. */
845 ust_app_global_update_all(session);
846 } else {
847 struct ust_app *app;
848
849 ret = pid_tracker_add_pid(&session->pid_tracker, pid);
850 if (ret != LTTNG_OK) {
851 retval = ret;
852 goto end;
853 }
854 /* Add session to application */
855 app = ust_app_find_by_pid(pid);
856 if (app) {
857 ust_app_global_update(session, app);
858 }
859 }
860 }
861 end:
862 return retval;
863 }
864
865 /*
866 * Called with the session lock held.
867 */
868 int trace_ust_untrack_pid(struct ltt_ust_session *session, int pid)
869 {
870 int retval = LTTNG_OK;
871
872 if (pid == -1) {
873 /* Create empty tracker, replace old tracker. */
874 struct ust_pid_tracker tmp_tracker;
875
876 tmp_tracker = session->pid_tracker;
877 if (init_pid_tracker(&session->pid_tracker)) {
878 ERR("Error initializing PID tracker");
879 retval = LTTNG_ERR_NOMEM;
880 /* Rollback operation. */
881 session->pid_tracker = tmp_tracker;
882 goto end;
883 }
884 fini_pid_tracker(&tmp_tracker);
885
886 /* Remove session from all applications */
887 ust_app_global_update_all(session);
888 } else {
889 int ret;
890 struct ust_app *app;
891
892 if (!session->pid_tracker.ht) {
893 /* No PID being tracked. */
894 retval = LTTNG_ERR_PID_NOT_TRACKED;
895 goto end;
896 }
897 /* Remove PID from tracker */
898 ret = pid_tracker_del_pid(&session->pid_tracker, pid);
899 if (ret != LTTNG_OK) {
900 retval = ret;
901 goto end;
902 }
903 /* Remove session from application. */
904 app = ust_app_find_by_pid(pid);
905 if (app) {
906 ust_app_global_update(session, app);
907 }
908 }
909 end:
910 return retval;
911 }
912
913 /*
914 * Called with session lock held.
915 */
916 ssize_t trace_ust_list_tracker_pids(struct ltt_ust_session *session,
917 int32_t **_pids)
918 {
919 struct ust_pid_tracker_node *tracker_node;
920 struct lttng_ht_iter iter;
921 unsigned long count, i = 0;
922 long approx[2];
923 int32_t *pids;
924 int ret = 0;
925
926 if (!session->pid_tracker.ht) {
927 /* Tracker disabled. Set first entry to -1. */
928 pids = zmalloc(sizeof(*pids));
929 if (!pids) {
930 ret = -1;
931 goto end;
932 }
933 pids[0] = -1;
934 *_pids = pids;
935 return 1;
936 }
937
938 rcu_read_lock();
939 cds_lfht_count_nodes(session->pid_tracker.ht->ht,
940 &approx[0], &count, &approx[1]);
941 pids = zmalloc(sizeof(*pids) * count);
942 if (!pids) {
943 ret = -1;
944 goto end;
945 }
946 cds_lfht_for_each_entry(session->pid_tracker.ht->ht,
947 &iter.iter, tracker_node, node.node) {
948 pids[i++] = tracker_node->node.key;
949 }
950 *_pids = pids;
951 ret = count;
952 end:
953 rcu_read_unlock();
954 return ret;
955 }
956
957 /*
958 * RCU safe free context structure.
959 */
960 static void destroy_context_rcu(struct rcu_head *head)
961 {
962 struct lttng_ht_node_ulong *node =
963 caa_container_of(head, struct lttng_ht_node_ulong, head);
964 struct ltt_ust_context *ctx =
965 caa_container_of(node, struct ltt_ust_context, node);
966
967 trace_ust_destroy_context(ctx);
968 }
969
970 /*
971 * Cleanup UST context hash table.
972 */
973 static void destroy_contexts(struct lttng_ht *ht)
974 {
975 int ret;
976 struct lttng_ht_node_ulong *node;
977 struct lttng_ht_iter iter;
978 struct ltt_ust_context *ctx;
979
980 assert(ht);
981
982 rcu_read_lock();
983 cds_lfht_for_each_entry(ht->ht, &iter.iter, node, node) {
984 /* Remove from ordered list. */
985 ctx = caa_container_of(node, struct ltt_ust_context, node);
986 cds_list_del(&ctx->list);
987 /* Remove from channel's hash table. */
988 ret = lttng_ht_del(ht, &iter);
989 if (!ret) {
990 call_rcu(&node->head, destroy_context_rcu);
991 }
992 }
993 rcu_read_unlock();
994
995 ht_cleanup_push(ht);
996 }
997
998 /*
999 * Cleanup ust event structure.
1000 */
1001 void trace_ust_destroy_event(struct ltt_ust_event *event)
1002 {
1003 assert(event);
1004
1005 DBG2("Trace destroy UST event %s", event->attr.name);
1006 free(event->filter_expression);
1007 free(event->filter);
1008 free(event->exclusion);
1009 free(event);
1010 }
1011
1012 /*
1013 * Cleanup ust context structure.
1014 */
1015 void trace_ust_destroy_context(struct ltt_ust_context *ctx)
1016 {
1017 assert(ctx);
1018
1019 if (ctx->ctx.ctx == LTTNG_UST_CONTEXT_APP_CONTEXT) {
1020 free(ctx->ctx.u.app_ctx.provider_name);
1021 free(ctx->ctx.u.app_ctx.ctx_name);
1022 }
1023 free(ctx);
1024 }
1025
1026 /*
1027 * URCU intermediate call to complete destroy event.
1028 */
1029 static void destroy_event_rcu(struct rcu_head *head)
1030 {
1031 struct lttng_ht_node_str *node =
1032 caa_container_of(head, struct lttng_ht_node_str, head);
1033 struct ltt_ust_event *event =
1034 caa_container_of(node, struct ltt_ust_event, node);
1035
1036 trace_ust_destroy_event(event);
1037 }
1038
1039 /*
1040 * Cleanup UST events hashtable.
1041 */
1042 static void destroy_events(struct lttng_ht *events)
1043 {
1044 int ret;
1045 struct lttng_ht_node_str *node;
1046 struct lttng_ht_iter iter;
1047
1048 assert(events);
1049
1050 rcu_read_lock();
1051 cds_lfht_for_each_entry(events->ht, &iter.iter, node, node) {
1052 ret = lttng_ht_del(events, &iter);
1053 assert(!ret);
1054 call_rcu(&node->head, destroy_event_rcu);
1055 }
1056 rcu_read_unlock();
1057
1058 ht_cleanup_push(events);
1059 }
1060
1061 /*
1062 * Cleanup ust channel structure.
1063 *
1064 * Should _NOT_ be called with RCU read lock held.
1065 */
1066 static void _trace_ust_destroy_channel(struct ltt_ust_channel *channel)
1067 {
1068 assert(channel);
1069
1070 DBG2("Trace destroy UST channel %s", channel->name);
1071
1072 free(channel);
1073 }
1074
1075 /*
1076 * URCU intermediate call to complete destroy channel.
1077 */
1078 static void destroy_channel_rcu(struct rcu_head *head)
1079 {
1080 struct lttng_ht_node_str *node =
1081 caa_container_of(head, struct lttng_ht_node_str, head);
1082 struct ltt_ust_channel *channel =
1083 caa_container_of(node, struct ltt_ust_channel, node);
1084
1085 _trace_ust_destroy_channel(channel);
1086 }
1087
1088 void trace_ust_destroy_channel(struct ltt_ust_channel *channel)
1089 {
1090 /* Destroying all events of the channel */
1091 destroy_events(channel->events);
1092 /* Destroying all context of the channel */
1093 destroy_contexts(channel->ctx);
1094
1095 call_rcu(&channel->node.head, destroy_channel_rcu);
1096 }
1097
1098 /*
1099 * Remove an UST channel from a channel HT.
1100 */
1101 void trace_ust_delete_channel(struct lttng_ht *ht,
1102 struct ltt_ust_channel *channel)
1103 {
1104 int ret;
1105 struct lttng_ht_iter iter;
1106
1107 assert(ht);
1108 assert(channel);
1109
1110 iter.iter.node = &channel->node.node;
1111 ret = lttng_ht_del(ht, &iter);
1112 assert(!ret);
1113 }
1114
1115 /*
1116 * Iterate over a hash table containing channels and cleanup safely.
1117 */
1118 static void destroy_channels(struct lttng_ht *channels)
1119 {
1120 struct lttng_ht_node_str *node;
1121 struct lttng_ht_iter iter;
1122
1123 assert(channels);
1124
1125 rcu_read_lock();
1126 cds_lfht_for_each_entry(channels->ht, &iter.iter, node, node) {
1127 struct ltt_ust_channel *chan =
1128 caa_container_of(node, struct ltt_ust_channel, node);
1129
1130 trace_ust_delete_channel(channels, chan);
1131 trace_ust_destroy_channel(chan);
1132 }
1133 rcu_read_unlock();
1134
1135 ht_cleanup_push(channels);
1136 }
1137
1138 /*
1139 * Cleanup UST global domain.
1140 */
1141 static void destroy_domain_global(struct ltt_ust_domain_global *dom)
1142 {
1143 assert(dom);
1144
1145 destroy_channels(dom->channels);
1146 }
1147
1148 /*
1149 * Cleanup ust session structure
1150 *
1151 * Should *NOT* be called with RCU read-side lock held.
1152 */
1153 void trace_ust_destroy_session(struct ltt_ust_session *session)
1154 {
1155 struct agent *agt;
1156 struct buffer_reg_uid *reg, *sreg;
1157 struct lttng_ht_iter iter;
1158
1159 assert(session);
1160
1161 DBG2("Trace UST destroy session %" PRIu64, session->id);
1162
1163 /* Cleaning up UST domain */
1164 destroy_domain_global(&session->domain_global);
1165
1166 rcu_read_lock();
1167 cds_lfht_for_each_entry(session->agents->ht, &iter.iter, agt, node.node) {
1168 int ret = lttng_ht_del(session->agents, &iter);
1169
1170 assert(!ret);
1171 agent_destroy(agt);
1172 }
1173 rcu_read_unlock();
1174
1175 ht_cleanup_push(session->agents);
1176
1177 /* Cleanup UID buffer registry object(s). */
1178 cds_list_for_each_entry_safe(reg, sreg, &session->buffer_reg_uid_list,
1179 lnode) {
1180 cds_list_del(&reg->lnode);
1181 buffer_reg_uid_remove(reg);
1182 buffer_reg_uid_destroy(reg, session->consumer);
1183 }
1184
1185 consumer_output_put(session->consumer);
1186
1187 fini_pid_tracker(&session->pid_tracker);
1188
1189 free(session);
1190 }
This page took 0.089704 seconds and 4 git commands to generate.