Fix: remove duplicate set ust event filter
[lttng-tools.git] / src / bin / lttng-sessiond / ust-app.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 <errno.h>
20 #include <pthread.h>
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <string.h>
24 #include <sys/stat.h>
25 #include <sys/types.h>
26 #include <unistd.h>
27 #include <urcu/compiler.h>
28 #include <lttng/ust-error.h>
29
30 #include <common/common.h>
31 #include <common/sessiond-comm/sessiond-comm.h>
32
33 #include "fd-limit.h"
34 #include "health.h"
35 #include "ust-app.h"
36 #include "ust-consumer.h"
37 #include "ust-ctl.h"
38
39 /*
40 * Match function for the hash table lookup.
41 *
42 * It matches an ust app event based on three attributes which are the event
43 * name, the filter bytecode and the loglevel.
44 */
45 static int ht_match_ust_app_event(struct cds_lfht_node *node, const void *_key)
46 {
47 struct ust_app_event *event;
48 const struct ust_app_ht_key *key;
49
50 assert(node);
51 assert(_key);
52
53 event = caa_container_of(node, struct ust_app_event, node.node);
54 key = _key;
55
56 /* Match the 3 elements of the key: name, filter and loglevel. */
57
58 /* Event name */
59 if (strncmp(event->attr.name, key->name, sizeof(event->attr.name)) != 0) {
60 goto no_match;
61 }
62
63 /* Event loglevel. */
64 if (event->attr.loglevel != key->loglevel) {
65 if (event->attr.loglevel_type == LTTNG_UST_LOGLEVEL_ALL
66 && key->loglevel == 0 && event->attr.loglevel == -1) {
67 /*
68 * Match is accepted. This is because on event creation, the
69 * loglevel is set to -1 if the event loglevel type is ALL so 0 and
70 * -1 are accepted for this loglevel type since 0 is the one set by
71 * the API when receiving an enable event.
72 */
73 } else {
74 goto no_match;
75 }
76 }
77
78 /* One of the filters is NULL, fail. */
79 if ((key->filter && !event->filter) || (!key->filter && event->filter)) {
80 goto no_match;
81 }
82
83 if (key->filter && event->filter) {
84 /* Both filters exists, check length followed by the bytecode. */
85 if (event->filter->len != key->filter->len ||
86 memcmp(event->filter->data, key->filter->data,
87 event->filter->len) != 0) {
88 goto no_match;
89 }
90 }
91
92 /* Match. */
93 return 1;
94
95 no_match:
96 return 0;
97 }
98
99 /*
100 * Unique add of an ust app event in the given ht. This uses the custom
101 * ht_match_ust_app_event match function and the event name as hash.
102 */
103 static void add_unique_ust_app_event(struct lttng_ht *ht,
104 struct ust_app_event *event)
105 {
106 struct cds_lfht_node *node_ptr;
107 struct ust_app_ht_key key;
108
109 assert(ht);
110 assert(ht->ht);
111 assert(event);
112
113 key.name = event->attr.name;
114 key.filter = event->filter;
115 key.loglevel = event->attr.loglevel;
116
117 node_ptr = cds_lfht_add_unique(ht->ht,
118 ht->hash_fct(event->node.key, lttng_ht_seed),
119 ht_match_ust_app_event, &key, &event->node.node);
120 assert(node_ptr == &event->node.node);
121 }
122
123 /*
124 * Delete ust context safely. RCU read lock must be held before calling
125 * this function.
126 */
127 static
128 void delete_ust_app_ctx(int sock, struct ust_app_ctx *ua_ctx)
129 {
130 if (ua_ctx->obj) {
131 ustctl_release_object(sock, ua_ctx->obj);
132 free(ua_ctx->obj);
133 }
134 free(ua_ctx);
135 }
136
137 /*
138 * Delete ust app event safely. RCU read lock must be held before calling
139 * this function.
140 */
141 static
142 void delete_ust_app_event(int sock, struct ust_app_event *ua_event)
143 {
144 free(ua_event->filter);
145
146 if (ua_event->obj != NULL) {
147 ustctl_release_object(sock, ua_event->obj);
148 free(ua_event->obj);
149 }
150 free(ua_event);
151 }
152
153 /*
154 * Delete ust app stream safely. RCU read lock must be held before calling
155 * this function.
156 */
157 static
158 void delete_ust_app_stream(int sock, struct ltt_ust_stream *stream)
159 {
160 if (stream->obj) {
161 ustctl_release_object(sock, stream->obj);
162 lttng_fd_put(LTTNG_FD_APPS, 2);
163 free(stream->obj);
164 }
165 free(stream);
166 }
167
168 /*
169 * Delete ust app channel safely. RCU read lock must be held before calling
170 * this function.
171 */
172 static
173 void delete_ust_app_channel(int sock, struct ust_app_channel *ua_chan)
174 {
175 int ret;
176 struct lttng_ht_iter iter;
177 struct ust_app_event *ua_event;
178 struct ust_app_ctx *ua_ctx;
179 struct ltt_ust_stream *stream, *stmp;
180
181 /* Wipe stream */
182 cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
183 cds_list_del(&stream->list);
184 delete_ust_app_stream(sock, stream);
185 }
186
187 /* Wipe context */
188 cds_lfht_for_each_entry(ua_chan->ctx->ht, &iter.iter, ua_ctx, node.node) {
189 ret = lttng_ht_del(ua_chan->ctx, &iter);
190 assert(!ret);
191 delete_ust_app_ctx(sock, ua_ctx);
192 }
193 lttng_ht_destroy(ua_chan->ctx);
194
195 /* Wipe events */
196 cds_lfht_for_each_entry(ua_chan->events->ht, &iter.iter, ua_event,
197 node.node) {
198 ret = lttng_ht_del(ua_chan->events, &iter);
199 assert(!ret);
200 delete_ust_app_event(sock, ua_event);
201 }
202 lttng_ht_destroy(ua_chan->events);
203
204 if (ua_chan->obj != NULL) {
205 ustctl_release_object(sock, ua_chan->obj);
206 lttng_fd_put(LTTNG_FD_APPS, 2);
207 free(ua_chan->obj);
208 }
209 free(ua_chan);
210 }
211
212 /*
213 * Delete ust app session safely. RCU read lock must be held before calling
214 * this function.
215 */
216 static
217 void delete_ust_app_session(int sock, struct ust_app_session *ua_sess)
218 {
219 int ret;
220 struct lttng_ht_iter iter;
221 struct ust_app_channel *ua_chan;
222
223 if (ua_sess->metadata) {
224 if (ua_sess->metadata->stream_obj) {
225 ustctl_release_object(sock, ua_sess->metadata->stream_obj);
226 lttng_fd_put(LTTNG_FD_APPS, 2);
227 free(ua_sess->metadata->stream_obj);
228 }
229 if (ua_sess->metadata->obj) {
230 ustctl_release_object(sock, ua_sess->metadata->obj);
231 lttng_fd_put(LTTNG_FD_APPS, 2);
232 free(ua_sess->metadata->obj);
233 }
234 trace_ust_destroy_metadata(ua_sess->metadata);
235 }
236
237 cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
238 node.node) {
239 ret = lttng_ht_del(ua_sess->channels, &iter);
240 assert(!ret);
241 delete_ust_app_channel(sock, ua_chan);
242 }
243 lttng_ht_destroy(ua_sess->channels);
244
245 if (ua_sess->handle != -1) {
246 ustctl_release_handle(sock, ua_sess->handle);
247 }
248 free(ua_sess);
249 }
250
251 /*
252 * Delete a traceable application structure from the global list. Never call
253 * this function outside of a call_rcu call.
254 */
255 static
256 void delete_ust_app(struct ust_app *app)
257 {
258 int ret, sock;
259 struct ust_app_session *ua_sess, *tmp_ua_sess;
260
261 rcu_read_lock();
262
263 /* Delete ust app sessions info */
264 sock = app->sock;
265 app->sock = -1;
266
267 lttng_ht_destroy(app->sessions);
268
269 /* Wipe sessions */
270 cds_list_for_each_entry_safe(ua_sess, tmp_ua_sess, &app->teardown_head,
271 teardown_node) {
272 /* Free every object in the session and the session. */
273 delete_ust_app_session(sock, ua_sess);
274 }
275
276 /*
277 * Wait until we have deleted the application from the sock hash table
278 * before closing this socket, otherwise an application could re-use the
279 * socket ID and race with the teardown, using the same hash table entry.
280 *
281 * It's OK to leave the close in call_rcu. We want it to stay unique for
282 * all RCU readers that could run concurrently with unregister app,
283 * therefore we _need_ to only close that socket after a grace period. So
284 * it should stay in this RCU callback.
285 *
286 * This close() is a very important step of the synchronization model so
287 * every modification to this function must be carefully reviewed.
288 */
289 ret = close(sock);
290 if (ret) {
291 PERROR("close");
292 }
293 lttng_fd_put(LTTNG_FD_APPS, 1);
294
295 DBG2("UST app pid %d deleted", app->pid);
296 free(app);
297
298 rcu_read_unlock();
299 }
300
301 /*
302 * URCU intermediate call to delete an UST app.
303 */
304 static
305 void delete_ust_app_rcu(struct rcu_head *head)
306 {
307 struct lttng_ht_node_ulong *node =
308 caa_container_of(head, struct lttng_ht_node_ulong, head);
309 struct ust_app *app =
310 caa_container_of(node, struct ust_app, pid_n);
311
312 DBG3("Call RCU deleting app PID %d", app->pid);
313 delete_ust_app(app);
314 }
315
316 /*
317 * Alloc new UST app session.
318 */
319 static
320 struct ust_app_session *alloc_ust_app_session(void)
321 {
322 struct ust_app_session *ua_sess;
323
324 /* Init most of the default value by allocating and zeroing */
325 ua_sess = zmalloc(sizeof(struct ust_app_session));
326 if (ua_sess == NULL) {
327 PERROR("malloc");
328 goto error;
329 }
330
331 ua_sess->handle = -1;
332 ua_sess->channels = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
333
334 return ua_sess;
335
336 error:
337 return NULL;
338 }
339
340 /*
341 * Alloc new UST app channel.
342 */
343 static
344 struct ust_app_channel *alloc_ust_app_channel(char *name,
345 struct lttng_ust_channel *attr)
346 {
347 struct ust_app_channel *ua_chan;
348
349 /* Init most of the default value by allocating and zeroing */
350 ua_chan = zmalloc(sizeof(struct ust_app_channel));
351 if (ua_chan == NULL) {
352 PERROR("malloc");
353 goto error;
354 }
355
356 /* Setup channel name */
357 strncpy(ua_chan->name, name, sizeof(ua_chan->name));
358 ua_chan->name[sizeof(ua_chan->name) - 1] = '\0';
359
360 ua_chan->enabled = 1;
361 ua_chan->handle = -1;
362 ua_chan->ctx = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
363 ua_chan->events = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
364 lttng_ht_node_init_str(&ua_chan->node, ua_chan->name);
365
366 CDS_INIT_LIST_HEAD(&ua_chan->streams.head);
367
368 /* Copy attributes */
369 if (attr) {
370 memcpy(&ua_chan->attr, attr, sizeof(ua_chan->attr));
371 }
372
373 DBG3("UST app channel %s allocated", ua_chan->name);
374
375 return ua_chan;
376
377 error:
378 return NULL;
379 }
380
381 /*
382 * Alloc new UST app event.
383 */
384 static
385 struct ust_app_event *alloc_ust_app_event(char *name,
386 struct lttng_ust_event *attr)
387 {
388 struct ust_app_event *ua_event;
389
390 /* Init most of the default value by allocating and zeroing */
391 ua_event = zmalloc(sizeof(struct ust_app_event));
392 if (ua_event == NULL) {
393 PERROR("malloc");
394 goto error;
395 }
396
397 ua_event->enabled = 1;
398 strncpy(ua_event->name, name, sizeof(ua_event->name));
399 ua_event->name[sizeof(ua_event->name) - 1] = '\0';
400 lttng_ht_node_init_str(&ua_event->node, ua_event->name);
401
402 /* Copy attributes */
403 if (attr) {
404 memcpy(&ua_event->attr, attr, sizeof(ua_event->attr));
405 }
406
407 DBG3("UST app event %s allocated", ua_event->name);
408
409 return ua_event;
410
411 error:
412 return NULL;
413 }
414
415 /*
416 * Alloc new UST app context.
417 */
418 static
419 struct ust_app_ctx *alloc_ust_app_ctx(struct lttng_ust_context *uctx)
420 {
421 struct ust_app_ctx *ua_ctx;
422
423 ua_ctx = zmalloc(sizeof(struct ust_app_ctx));
424 if (ua_ctx == NULL) {
425 goto error;
426 }
427
428 if (uctx) {
429 memcpy(&ua_ctx->ctx, uctx, sizeof(ua_ctx->ctx));
430 }
431
432 DBG3("UST app context %d allocated", ua_ctx->ctx.ctx);
433
434 error:
435 return ua_ctx;
436 }
437
438 /*
439 * Allocate a filter and copy the given original filter.
440 *
441 * Return allocated filter or NULL on error.
442 */
443 static struct lttng_ust_filter_bytecode *alloc_copy_ust_app_filter(
444 struct lttng_ust_filter_bytecode *orig_f)
445 {
446 struct lttng_ust_filter_bytecode *filter = NULL;
447
448 /* Copy filter bytecode */
449 filter = zmalloc(sizeof(*filter) + orig_f->len);
450 if (!filter) {
451 PERROR("zmalloc alloc ust app filter");
452 goto error;
453 }
454
455 memcpy(filter, orig_f, sizeof(*filter) + orig_f->len);
456
457 error:
458 return filter;
459 }
460
461 /*
462 * Find an ust_app using the sock and return it. RCU read side lock must be
463 * held before calling this helper function.
464 */
465 static
466 struct ust_app *find_app_by_sock(int sock)
467 {
468 struct lttng_ht_node_ulong *node;
469 struct lttng_ht_iter iter;
470
471 lttng_ht_lookup(ust_app_ht_by_sock, (void *)((unsigned long) sock), &iter);
472 node = lttng_ht_iter_get_node_ulong(&iter);
473 if (node == NULL) {
474 DBG2("UST app find by sock %d not found", sock);
475 goto error;
476 }
477
478 return caa_container_of(node, struct ust_app, sock_n);
479
480 error:
481 return NULL;
482 }
483
484 /*
485 * Lookup for an ust app event based on event name, filter bytecode and the
486 * event loglevel.
487 *
488 * Return an ust_app_event object or NULL on error.
489 */
490 static struct ust_app_event *find_ust_app_event(struct lttng_ht *ht,
491 char *name, struct lttng_ust_filter_bytecode *filter, int loglevel)
492 {
493 struct lttng_ht_iter iter;
494 struct lttng_ht_node_str *node;
495 struct ust_app_event *event = NULL;
496 struct ust_app_ht_key key;
497
498 assert(name);
499 assert(ht);
500
501 /* Setup key for event lookup. */
502 key.name = name;
503 key.filter = filter;
504 key.loglevel = loglevel;
505
506 /* Lookup using the event name as hash and a custom match fct. */
507 cds_lfht_lookup(ht->ht, ht->hash_fct((void *) name, lttng_ht_seed),
508 ht_match_ust_app_event, &key, &iter.iter);
509 node = lttng_ht_iter_get_node_str(&iter);
510 if (node == NULL) {
511 goto end;
512 }
513
514 event = caa_container_of(node, struct ust_app_event, node);
515
516 end:
517 return event;
518 }
519
520 /*
521 * Create the channel context on the tracer.
522 */
523 static
524 int create_ust_channel_context(struct ust_app_channel *ua_chan,
525 struct ust_app_ctx *ua_ctx, struct ust_app *app)
526 {
527 int ret;
528
529 health_code_update(&health_thread_cmd);
530
531 ret = ustctl_add_context(app->sock, &ua_ctx->ctx,
532 ua_chan->obj, &ua_ctx->obj);
533 if (ret < 0) {
534 goto error;
535 }
536
537 ua_ctx->handle = ua_ctx->obj->handle;
538
539 DBG2("UST app context created successfully for channel %s", ua_chan->name);
540
541 error:
542 health_code_update(&health_thread_cmd);
543 return ret;
544 }
545
546 /*
547 * Set the filter on the tracer.
548 */
549 static
550 int set_ust_event_filter(struct ust_app_event *ua_event,
551 struct ust_app *app)
552 {
553 int ret;
554
555 health_code_update(&health_thread_cmd);
556
557 if (!ua_event->filter) {
558 ret = 0;
559 goto error;
560 }
561
562 ret = ustctl_set_filter(app->sock, ua_event->filter,
563 ua_event->obj);
564 if (ret < 0) {
565 goto error;
566 }
567
568 DBG2("UST filter set successfully for event %s", ua_event->name);
569
570 error:
571 health_code_update(&health_thread_cmd);
572 return ret;
573 }
574
575 /*
576 * Disable the specified event on to UST tracer for the UST session.
577 */
578 static int disable_ust_event(struct ust_app *app,
579 struct ust_app_session *ua_sess, struct ust_app_event *ua_event)
580 {
581 int ret;
582
583 health_code_update(&health_thread_cmd);
584
585 ret = ustctl_disable(app->sock, ua_event->obj);
586 if (ret < 0) {
587 ERR("UST app event %s disable failed for app (pid: %d) "
588 "and session handle %d with ret %d",
589 ua_event->attr.name, app->pid, ua_sess->handle, ret);
590 goto error;
591 }
592
593 DBG2("UST app event %s disabled successfully for app (pid: %d)",
594 ua_event->attr.name, app->pid);
595
596 error:
597 health_code_update(&health_thread_cmd);
598 return ret;
599 }
600
601 /*
602 * Disable the specified channel on to UST tracer for the UST session.
603 */
604 static int disable_ust_channel(struct ust_app *app,
605 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
606 {
607 int ret;
608
609 health_code_update(&health_thread_cmd);
610
611 ret = ustctl_disable(app->sock, ua_chan->obj);
612 if (ret < 0) {
613 ERR("UST app channel %s disable failed for app (pid: %d) "
614 "and session handle %d with ret %d",
615 ua_chan->name, app->pid, ua_sess->handle, ret);
616 goto error;
617 }
618
619 DBG2("UST app channel %s disabled successfully for app (pid: %d)",
620 ua_chan->name, app->pid);
621
622 error:
623 health_code_update(&health_thread_cmd);
624 return ret;
625 }
626
627 /*
628 * Enable the specified channel on to UST tracer for the UST session.
629 */
630 static int enable_ust_channel(struct ust_app *app,
631 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
632 {
633 int ret;
634
635 health_code_update(&health_thread_cmd);
636
637 ret = ustctl_enable(app->sock, ua_chan->obj);
638 if (ret < 0) {
639 ERR("UST app channel %s enable failed for app (pid: %d) "
640 "and session handle %d with ret %d",
641 ua_chan->name, app->pid, ua_sess->handle, ret);
642 goto error;
643 }
644
645 ua_chan->enabled = 1;
646
647 DBG2("UST app channel %s enabled successfully for app (pid: %d)",
648 ua_chan->name, app->pid);
649
650 error:
651 health_code_update(&health_thread_cmd);
652 return ret;
653 }
654
655 /*
656 * Enable the specified event on to UST tracer for the UST session.
657 */
658 static int enable_ust_event(struct ust_app *app,
659 struct ust_app_session *ua_sess, struct ust_app_event *ua_event)
660 {
661 int ret;
662
663 health_code_update(&health_thread_cmd);
664
665 ret = ustctl_enable(app->sock, ua_event->obj);
666 if (ret < 0) {
667 ERR("UST app event %s enable failed for app (pid: %d) "
668 "and session handle %d with ret %d",
669 ua_event->attr.name, app->pid, ua_sess->handle, ret);
670 goto error;
671 }
672
673 DBG2("UST app event %s enabled successfully for app (pid: %d)",
674 ua_event->attr.name, app->pid);
675
676 error:
677 health_code_update(&health_thread_cmd);
678 return ret;
679 }
680
681 /*
682 * Open metadata onto the UST tracer for a UST session.
683 */
684 static int open_ust_metadata(struct ust_app *app,
685 struct ust_app_session *ua_sess)
686 {
687 int ret;
688 struct lttng_ust_channel_attr uattr;
689
690 health_code_update(&health_thread_cmd);
691
692 uattr.overwrite = ua_sess->metadata->attr.overwrite;
693 uattr.subbuf_size = ua_sess->metadata->attr.subbuf_size;
694 uattr.num_subbuf = ua_sess->metadata->attr.num_subbuf;
695 uattr.switch_timer_interval =
696 ua_sess->metadata->attr.switch_timer_interval;
697 uattr.read_timer_interval =
698 ua_sess->metadata->attr.read_timer_interval;
699 uattr.output = ua_sess->metadata->attr.output;
700
701 /* We are going to receive 2 fds, we need to reserve them. */
702 ret = lttng_fd_get(LTTNG_FD_APPS, 2);
703 if (ret < 0) {
704 ERR("Exhausted number of available FD upon metadata open");
705 goto error;
706 }
707 /* UST tracer metadata creation */
708 ret = ustctl_open_metadata(app->sock, ua_sess->handle, &uattr,
709 &ua_sess->metadata->obj);
710 if (ret < 0) {
711 ERR("UST app open metadata failed for app pid:%d with ret %d",
712 app->pid, ret);
713 goto error;
714 }
715
716 ua_sess->metadata->handle = ua_sess->metadata->obj->handle;
717
718 error:
719 health_code_update(&health_thread_cmd);
720 return ret;
721 }
722
723 /*
724 * Create stream onto the UST tracer for a UST session.
725 */
726 static int create_ust_stream(struct ust_app *app,
727 struct ust_app_session *ua_sess)
728 {
729 int ret;
730
731 health_code_update(&health_thread_cmd);
732
733 /* We are going to receive 2 fds, we need to reserve them. */
734 ret = lttng_fd_get(LTTNG_FD_APPS, 2);
735 if (ret < 0) {
736 ERR("Exhausted number of available FD upon metadata stream create");
737 goto error;
738 }
739 ret = ustctl_create_stream(app->sock, ua_sess->metadata->obj,
740 &ua_sess->metadata->stream_obj);
741 if (ret < 0) {
742 ERR("UST create metadata stream failed");
743 goto error;
744 }
745
746 error:
747 health_code_update(&health_thread_cmd);
748 return ret;
749 }
750
751 /*
752 * Create the specified channel onto the UST tracer for a UST session.
753 */
754 static int create_ust_channel(struct ust_app *app,
755 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
756 {
757 int ret;
758
759 health_code_update(&health_thread_cmd);
760
761 /* TODO: remove cast and use lttng-ust-abi.h */
762
763 /* We are going to receive 2 fds, we need to reserve them. */
764 ret = lttng_fd_get(LTTNG_FD_APPS, 2);
765 if (ret < 0) {
766 ERR("Exhausted number of available FD upon create channel");
767 goto error;
768 }
769
770 health_code_update(&health_thread_cmd);
771
772 ret = ustctl_create_channel(app->sock, ua_sess->handle,
773 (struct lttng_ust_channel_attr *)&ua_chan->attr, &ua_chan->obj);
774 if (ret < 0) {
775 ERR("Creating channel %s for app (pid: %d, sock: %d) "
776 "and session handle %d with ret %d",
777 ua_chan->name, app->pid, app->sock,
778 ua_sess->handle, ret);
779 lttng_fd_put(LTTNG_FD_APPS, 2);
780 goto error;
781 }
782
783 ua_chan->handle = ua_chan->obj->handle;
784
785 DBG2("UST app channel %s created successfully for pid:%d and sock:%d",
786 ua_chan->name, app->pid, app->sock);
787
788 health_code_update(&health_thread_cmd);
789
790 /* If channel is not enabled, disable it on the tracer */
791 if (!ua_chan->enabled) {
792 ret = disable_ust_channel(app, ua_sess, ua_chan);
793 if (ret < 0) {
794 goto error;
795 }
796 }
797
798 error:
799 health_code_update(&health_thread_cmd);
800 return ret;
801 }
802
803 /*
804 * Create the specified event onto the UST tracer for a UST session.
805 */
806 static
807 int create_ust_event(struct ust_app *app, struct ust_app_session *ua_sess,
808 struct ust_app_channel *ua_chan, struct ust_app_event *ua_event)
809 {
810 int ret = 0;
811
812 health_code_update(&health_thread_cmd);
813
814 /* Create UST event on tracer */
815 ret = ustctl_create_event(app->sock, &ua_event->attr, ua_chan->obj,
816 &ua_event->obj);
817 if (ret < 0) {
818 ERR("Error ustctl create event %s for app pid: %d with ret %d",
819 ua_event->attr.name, app->pid, ret);
820 goto error;
821 }
822
823 ua_event->handle = ua_event->obj->handle;
824
825 DBG2("UST app event %s created successfully for pid:%d",
826 ua_event->attr.name, app->pid);
827
828 health_code_update(&health_thread_cmd);
829
830 /* Set filter if one is present. */
831 if (ua_event->filter) {
832 ret = set_ust_event_filter(ua_event, app);
833 if (ret < 0) {
834 goto error;
835 }
836 }
837
838 /* If event not enabled, disable it on the tracer */
839 if (ua_event->enabled == 0) {
840 ret = disable_ust_event(app, ua_sess, ua_event);
841 if (ret < 0) {
842 /*
843 * If we hit an EPERM, something is wrong with our disable call. If
844 * we get an EEXIST, there is a problem on the tracer side since we
845 * just created it.
846 */
847 switch (ret) {
848 case -LTTNG_UST_ERR_PERM:
849 /* Code flow problem */
850 assert(0);
851 case -LTTNG_UST_ERR_EXIST:
852 /* It's OK for our use case. */
853 ret = 0;
854 break;
855 default:
856 break;
857 }
858 goto error;
859 }
860 }
861
862 error:
863 health_code_update(&health_thread_cmd);
864 return ret;
865 }
866
867 /*
868 * Copy data between an UST app event and a LTT event.
869 */
870 static void shadow_copy_event(struct ust_app_event *ua_event,
871 struct ltt_ust_event *uevent)
872 {
873 strncpy(ua_event->name, uevent->attr.name, sizeof(ua_event->name));
874 ua_event->name[sizeof(ua_event->name) - 1] = '\0';
875
876 ua_event->enabled = uevent->enabled;
877
878 /* Copy event attributes */
879 memcpy(&ua_event->attr, &uevent->attr, sizeof(ua_event->attr));
880
881 /* Copy filter bytecode */
882 if (uevent->filter) {
883 ua_event->filter = alloc_copy_ust_app_filter(uevent->filter);
884 /* Filter might be NULL here in case of ENONEM. */
885 }
886 }
887
888 /*
889 * Copy data between an UST app channel and a LTT channel.
890 */
891 static void shadow_copy_channel(struct ust_app_channel *ua_chan,
892 struct ltt_ust_channel *uchan)
893 {
894 struct lttng_ht_iter iter;
895 struct ltt_ust_event *uevent;
896 struct ltt_ust_context *uctx;
897 struct ust_app_event *ua_event;
898 struct ust_app_ctx *ua_ctx;
899
900 DBG2("UST app shadow copy of channel %s started", ua_chan->name);
901
902 strncpy(ua_chan->name, uchan->name, sizeof(ua_chan->name));
903 ua_chan->name[sizeof(ua_chan->name) - 1] = '\0';
904 /* Copy event attributes */
905 memcpy(&ua_chan->attr, &uchan->attr, sizeof(ua_chan->attr));
906
907 ua_chan->enabled = uchan->enabled;
908
909 cds_lfht_for_each_entry(uchan->ctx->ht, &iter.iter, uctx, node.node) {
910 ua_ctx = alloc_ust_app_ctx(&uctx->ctx);
911 if (ua_ctx == NULL) {
912 continue;
913 }
914 lttng_ht_node_init_ulong(&ua_ctx->node,
915 (unsigned long) ua_ctx->ctx.ctx);
916 lttng_ht_add_unique_ulong(ua_chan->ctx, &ua_ctx->node);
917 }
918
919 /* Copy all events from ltt ust channel to ust app channel */
920 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
921 ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name,
922 uevent->filter, uevent->attr.loglevel);
923 if (ua_event == NULL) {
924 DBG2("UST event %s not found on shadow copy channel",
925 uevent->attr.name);
926 ua_event = alloc_ust_app_event(uevent->attr.name, &uevent->attr);
927 if (ua_event == NULL) {
928 continue;
929 }
930 shadow_copy_event(ua_event, uevent);
931 add_unique_ust_app_event(ua_chan->events, ua_event);
932 }
933 }
934
935 DBG3("UST app shadow copy of channel %s done", ua_chan->name);
936 }
937
938 /*
939 * Copy data between a UST app session and a regular LTT session.
940 */
941 static void shadow_copy_session(struct ust_app_session *ua_sess,
942 struct ltt_ust_session *usess, struct ust_app *app)
943 {
944 struct lttng_ht_node_str *ua_chan_node;
945 struct lttng_ht_iter iter;
946 struct ltt_ust_channel *uchan;
947 struct ust_app_channel *ua_chan;
948 time_t rawtime;
949 struct tm *timeinfo;
950 char datetime[16];
951 int ret;
952
953 /* Get date and time for unique app path */
954 time(&rawtime);
955 timeinfo = localtime(&rawtime);
956 strftime(datetime, sizeof(datetime), "%Y%m%d-%H%M%S", timeinfo);
957
958 DBG2("Shadow copy of session handle %d", ua_sess->handle);
959
960 ua_sess->id = usess->id;
961 ua_sess->uid = usess->uid;
962 ua_sess->gid = usess->gid;
963
964 ret = snprintf(ua_sess->path, PATH_MAX, "%s-%d-%s/", app->name, app->pid,
965 datetime);
966 if (ret < 0) {
967 PERROR("asprintf UST shadow copy session");
968 /* TODO: We cannot return an error from here.. */
969 assert(0);
970 }
971
972 /* TODO: support all UST domain */
973
974 /* Iterate over all channels in global domain. */
975 cds_lfht_for_each_entry(usess->domain_global.channels->ht, &iter.iter,
976 uchan, node.node) {
977 struct lttng_ht_iter uiter;
978
979 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
980 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
981 if (ua_chan_node != NULL) {
982 /* Session exist. Contiuing. */
983 continue;
984 }
985
986 DBG2("Channel %s not found on shadow session copy, creating it",
987 uchan->name);
988 ua_chan = alloc_ust_app_channel(uchan->name, &uchan->attr);
989 if (ua_chan == NULL) {
990 /* malloc failed FIXME: Might want to do handle ENOMEM .. */
991 continue;
992 }
993
994 shadow_copy_channel(ua_chan, uchan);
995 lttng_ht_add_unique_str(ua_sess->channels, &ua_chan->node);
996 }
997 }
998
999 /*
1000 * Lookup sesison wrapper.
1001 */
1002 static
1003 void __lookup_session_by_app(struct ltt_ust_session *usess,
1004 struct ust_app *app, struct lttng_ht_iter *iter)
1005 {
1006 /* Get right UST app session from app */
1007 lttng_ht_lookup(app->sessions, (void *)((unsigned long) usess->id), iter);
1008 }
1009
1010 /*
1011 * Return ust app session from the app session hashtable using the UST session
1012 * id.
1013 */
1014 static struct ust_app_session *lookup_session_by_app(
1015 struct ltt_ust_session *usess, struct ust_app *app)
1016 {
1017 struct lttng_ht_iter iter;
1018 struct lttng_ht_node_ulong *node;
1019
1020 __lookup_session_by_app(usess, app, &iter);
1021 node = lttng_ht_iter_get_node_ulong(&iter);
1022 if (node == NULL) {
1023 goto error;
1024 }
1025
1026 return caa_container_of(node, struct ust_app_session, node);
1027
1028 error:
1029 return NULL;
1030 }
1031
1032 /*
1033 * Create a UST session onto the tracer of app and add it the session
1034 * hashtable.
1035 *
1036 * Return ust app session or NULL on error.
1037 */
1038 static struct ust_app_session *create_ust_app_session(
1039 struct ltt_ust_session *usess, struct ust_app *app)
1040 {
1041 struct ust_app_session *ua_sess;
1042
1043 health_code_update(&health_thread_cmd);
1044
1045 ua_sess = lookup_session_by_app(usess, app);
1046 if (ua_sess == NULL) {
1047 DBG2("UST app pid: %d session id %d not found, creating it",
1048 app->pid, usess->id);
1049 ua_sess = alloc_ust_app_session();
1050 if (ua_sess == NULL) {
1051 /* Only malloc can failed so something is really wrong */
1052 goto end;
1053 }
1054 shadow_copy_session(ua_sess, usess, app);
1055 }
1056
1057 health_code_update(&health_thread_cmd);
1058
1059 if (ua_sess->handle == -1) {
1060 int ret;
1061
1062 ret = ustctl_create_session(app->sock);
1063 if (ret < 0) {
1064 ERR("Creating session for app pid %d", app->pid);
1065 delete_ust_app_session(-1, ua_sess);
1066 /* This means that the tracer is gone... */
1067 ua_sess = (void*) -1UL;
1068 goto end;
1069 }
1070
1071 ua_sess->handle = ret;
1072
1073 /* Add ust app session to app's HT */
1074 lttng_ht_node_init_ulong(&ua_sess->node, (unsigned long) ua_sess->id);
1075 lttng_ht_add_unique_ulong(app->sessions, &ua_sess->node);
1076
1077 DBG2("UST app session created successfully with handle %d", ret);
1078 }
1079
1080 end:
1081 health_code_update(&health_thread_cmd);
1082 return ua_sess;
1083 }
1084
1085 /*
1086 * Create a context for the channel on the tracer.
1087 */
1088 static
1089 int create_ust_app_channel_context(struct ust_app_session *ua_sess,
1090 struct ust_app_channel *ua_chan, struct lttng_ust_context *uctx,
1091 struct ust_app *app)
1092 {
1093 int ret = 0;
1094 struct lttng_ht_iter iter;
1095 struct lttng_ht_node_ulong *node;
1096 struct ust_app_ctx *ua_ctx;
1097
1098 DBG2("UST app adding context to channel %s", ua_chan->name);
1099
1100 lttng_ht_lookup(ua_chan->ctx, (void *)((unsigned long)uctx->ctx), &iter);
1101 node = lttng_ht_iter_get_node_ulong(&iter);
1102 if (node != NULL) {
1103 ret = -EEXIST;
1104 goto error;
1105 }
1106
1107 ua_ctx = alloc_ust_app_ctx(uctx);
1108 if (ua_ctx == NULL) {
1109 /* malloc failed */
1110 ret = -1;
1111 goto error;
1112 }
1113
1114 lttng_ht_node_init_ulong(&ua_ctx->node, (unsigned long) ua_ctx->ctx.ctx);
1115 lttng_ht_add_unique_ulong(ua_chan->ctx, &ua_ctx->node);
1116
1117 ret = create_ust_channel_context(ua_chan, ua_ctx, app);
1118 if (ret < 0) {
1119 goto error;
1120 }
1121
1122 error:
1123 return ret;
1124 }
1125
1126 /*
1127 * Enable on the tracer side a ust app event for the session and channel.
1128 */
1129 static
1130 int enable_ust_app_event(struct ust_app_session *ua_sess,
1131 struct ust_app_event *ua_event, struct ust_app *app)
1132 {
1133 int ret;
1134
1135 ret = enable_ust_event(app, ua_sess, ua_event);
1136 if (ret < 0) {
1137 goto error;
1138 }
1139
1140 ua_event->enabled = 1;
1141
1142 error:
1143 return ret;
1144 }
1145
1146 /*
1147 * Disable on the tracer side a ust app event for the session and channel.
1148 */
1149 static int disable_ust_app_event(struct ust_app_session *ua_sess,
1150 struct ust_app_event *ua_event, struct ust_app *app)
1151 {
1152 int ret;
1153
1154 ret = disable_ust_event(app, ua_sess, ua_event);
1155 if (ret < 0) {
1156 goto error;
1157 }
1158
1159 ua_event->enabled = 0;
1160
1161 error:
1162 return ret;
1163 }
1164
1165 /*
1166 * Lookup ust app channel for session and disable it on the tracer side.
1167 */
1168 static
1169 int disable_ust_app_channel(struct ust_app_session *ua_sess,
1170 struct ust_app_channel *ua_chan, struct ust_app *app)
1171 {
1172 int ret;
1173
1174 ret = disable_ust_channel(app, ua_sess, ua_chan);
1175 if (ret < 0) {
1176 goto error;
1177 }
1178
1179 ua_chan->enabled = 0;
1180
1181 error:
1182 return ret;
1183 }
1184
1185 /*
1186 * Lookup ust app channel for session and enable it on the tracer side.
1187 */
1188 static int enable_ust_app_channel(struct ust_app_session *ua_sess,
1189 struct ltt_ust_channel *uchan, struct ust_app *app)
1190 {
1191 int ret = 0;
1192 struct lttng_ht_iter iter;
1193 struct lttng_ht_node_str *ua_chan_node;
1194 struct ust_app_channel *ua_chan;
1195
1196 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
1197 ua_chan_node = lttng_ht_iter_get_node_str(&iter);
1198 if (ua_chan_node == NULL) {
1199 DBG2("Unable to find channel %s in ust session id %u",
1200 uchan->name, ua_sess->id);
1201 goto error;
1202 }
1203
1204 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
1205
1206 ret = enable_ust_channel(app, ua_sess, ua_chan);
1207 if (ret < 0) {
1208 goto error;
1209 }
1210
1211 error:
1212 return ret;
1213 }
1214
1215 /*
1216 * Create UST app channel and create it on the tracer. Set ua_chanp of the
1217 * newly created channel if not NULL.
1218 */
1219 static int create_ust_app_channel(struct ust_app_session *ua_sess,
1220 struct ltt_ust_channel *uchan, struct ust_app *app,
1221 struct ust_app_channel **ua_chanp)
1222 {
1223 int ret = 0;
1224 struct lttng_ht_iter iter;
1225 struct lttng_ht_node_str *ua_chan_node;
1226 struct ust_app_channel *ua_chan;
1227
1228 /* Lookup channel in the ust app session */
1229 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
1230 ua_chan_node = lttng_ht_iter_get_node_str(&iter);
1231 if (ua_chan_node != NULL) {
1232 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
1233 goto end;
1234 }
1235
1236 ua_chan = alloc_ust_app_channel(uchan->name, &uchan->attr);
1237 if (ua_chan == NULL) {
1238 /* Only malloc can fail here */
1239 ret = -ENOMEM;
1240 goto error;
1241 }
1242 shadow_copy_channel(ua_chan, uchan);
1243
1244 ret = create_ust_channel(app, ua_sess, ua_chan);
1245 if (ret < 0) {
1246 /* Not found previously means that it does not exist on the tracer */
1247 assert(ret != -LTTNG_UST_ERR_EXIST);
1248 goto error;
1249 }
1250
1251 /* Only add the channel if successful on the tracer side. */
1252 lttng_ht_add_unique_str(ua_sess->channels, &ua_chan->node);
1253
1254 DBG2("UST app create channel %s for PID %d completed", ua_chan->name,
1255 app->pid);
1256
1257 end:
1258 if (ua_chanp) {
1259 *ua_chanp = ua_chan;
1260 }
1261
1262 /* Everything went well. */
1263 return 0;
1264
1265 error:
1266 delete_ust_app_channel(-1, ua_chan);
1267 return ret;
1268 }
1269
1270 /*
1271 * Create UST app event and create it on the tracer side.
1272 */
1273 static
1274 int create_ust_app_event(struct ust_app_session *ua_sess,
1275 struct ust_app_channel *ua_chan, struct ltt_ust_event *uevent,
1276 struct ust_app *app)
1277 {
1278 int ret = 0;
1279 struct ust_app_event *ua_event;
1280
1281 /* Get event node */
1282 ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name,
1283 uevent->filter, uevent->attr.loglevel);
1284 if (ua_event != NULL) {
1285 ret = -EEXIST;
1286 goto end;
1287 }
1288
1289 /* Does not exist so create one */
1290 ua_event = alloc_ust_app_event(uevent->attr.name, &uevent->attr);
1291 if (ua_event == NULL) {
1292 /* Only malloc can failed so something is really wrong */
1293 ret = -ENOMEM;
1294 goto end;
1295 }
1296 shadow_copy_event(ua_event, uevent);
1297
1298 /* Create it on the tracer side */
1299 ret = create_ust_event(app, ua_sess, ua_chan, ua_event);
1300 if (ret < 0) {
1301 /* Not found previously means that it does not exist on the tracer */
1302 assert(ret != -LTTNG_UST_ERR_EXIST);
1303 goto error;
1304 }
1305
1306 add_unique_ust_app_event(ua_chan->events, ua_event);
1307
1308 DBG2("UST app create event %s for PID %d completed", ua_event->name,
1309 app->pid);
1310
1311 end:
1312 return ret;
1313
1314 error:
1315 /* Valid. Calling here is already in a read side lock */
1316 delete_ust_app_event(-1, ua_event);
1317 return ret;
1318 }
1319
1320 /*
1321 * Create UST metadata and open it on the tracer side.
1322 */
1323 static int create_ust_app_metadata(struct ust_app_session *ua_sess,
1324 char *pathname, struct ust_app *app)
1325 {
1326 int ret = 0;
1327
1328 if (ua_sess->metadata == NULL) {
1329 /* Allocate UST metadata */
1330 ua_sess->metadata = trace_ust_create_metadata(pathname);
1331 if (ua_sess->metadata == NULL) {
1332 /* malloc() failed */
1333 goto error;
1334 }
1335
1336 ret = open_ust_metadata(app, ua_sess);
1337 if (ret < 0) {
1338 DBG3("Opening metadata failed. Cleaning up memory");
1339
1340 /* Cleanup failed metadata struct */
1341 free(ua_sess->metadata);
1342 /*
1343 * This is very important because delete_ust_app_session check if
1344 * the pointer is null or not in order to delete the metadata.
1345 */
1346 ua_sess->metadata = NULL;
1347 goto error;
1348 }
1349
1350 DBG2("UST metadata opened for app pid %d", app->pid);
1351 }
1352
1353 /* Open UST metadata stream */
1354 if (ua_sess->metadata->stream_obj == NULL) {
1355 ret = create_ust_stream(app, ua_sess);
1356 if (ret < 0) {
1357 goto error;
1358 }
1359
1360 ret = snprintf(ua_sess->metadata->pathname, PATH_MAX,
1361 "%s/metadata", ua_sess->path);
1362 if (ret < 0) {
1363 PERROR("asprintf UST create stream");
1364 goto error;
1365 }
1366
1367 DBG2("UST metadata stream object created for app pid %d",
1368 app->pid);
1369 } else {
1370 ERR("Attempting to create stream without metadata opened");
1371 goto error;
1372 }
1373
1374 return 0;
1375
1376 error:
1377 return -1;
1378 }
1379
1380 /*
1381 * Return pointer to traceable apps list.
1382 */
1383 struct lttng_ht *ust_app_get_ht(void)
1384 {
1385 return ust_app_ht;
1386 }
1387
1388 /*
1389 * Return ust app pointer or NULL if not found.
1390 */
1391 struct ust_app *ust_app_find_by_pid(pid_t pid)
1392 {
1393 struct lttng_ht_node_ulong *node;
1394 struct lttng_ht_iter iter;
1395
1396 rcu_read_lock();
1397 lttng_ht_lookup(ust_app_ht, (void *)((unsigned long) pid), &iter);
1398 node = lttng_ht_iter_get_node_ulong(&iter);
1399 if (node == NULL) {
1400 DBG2("UST app no found with pid %d", pid);
1401 goto error;
1402 }
1403 rcu_read_unlock();
1404
1405 DBG2("Found UST app by pid %d", pid);
1406
1407 return caa_container_of(node, struct ust_app, pid_n);
1408
1409 error:
1410 rcu_read_unlock();
1411 return NULL;
1412 }
1413
1414 /*
1415 * Using pid and uid (of the app), allocate a new ust_app struct and
1416 * add it to the global traceable app list.
1417 *
1418 * On success, return 0, else return malloc -ENOMEM, or -EINVAL if app
1419 * bitness is not supported.
1420 */
1421 int ust_app_register(struct ust_register_msg *msg, int sock)
1422 {
1423 struct ust_app *lta;
1424 int ret;
1425
1426 if ((msg->bits_per_long == 64 &&
1427 (uatomic_read(&ust_consumerd64_fd) == -EINVAL))
1428 || (msg->bits_per_long == 32 &&
1429 (uatomic_read(&ust_consumerd32_fd) == -EINVAL))) {
1430 ERR("Registration failed: application \"%s\" (pid: %d) has "
1431 "%d-bit long, but no consumerd for this long size is available.\n",
1432 msg->name, msg->pid, msg->bits_per_long);
1433 ret = close(sock);
1434 if (ret) {
1435 PERROR("close");
1436 }
1437 lttng_fd_put(LTTNG_FD_APPS, 1);
1438 return -EINVAL;
1439 }
1440 if (msg->major != LTTNG_UST_COMM_MAJOR) {
1441 ERR("Registration failed: application \"%s\" (pid: %d) has "
1442 "communication protocol version %u.%u, but sessiond supports 2.x.\n",
1443 msg->name, msg->pid, msg->major, msg->minor);
1444 ret = close(sock);
1445 if (ret) {
1446 PERROR("close");
1447 }
1448 lttng_fd_put(LTTNG_FD_APPS, 1);
1449 return -EINVAL;
1450 }
1451 lta = zmalloc(sizeof(struct ust_app));
1452 if (lta == NULL) {
1453 PERROR("malloc");
1454 return -ENOMEM;
1455 }
1456
1457 lta->ppid = msg->ppid;
1458 lta->uid = msg->uid;
1459 lta->gid = msg->gid;
1460 lta->compatible = 0; /* Not compatible until proven */
1461 lta->bits_per_long = msg->bits_per_long;
1462 lta->v_major = msg->major;
1463 lta->v_minor = msg->minor;
1464 strncpy(lta->name, msg->name, sizeof(lta->name));
1465 lta->name[16] = '\0';
1466 lta->sessions = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
1467
1468 lta->pid = msg->pid;
1469 lttng_ht_node_init_ulong(&lta->pid_n, (unsigned long)lta->pid);
1470 lta->sock = sock;
1471 lttng_ht_node_init_ulong(&lta->sock_n, (unsigned long)lta->sock);
1472
1473 CDS_INIT_LIST_HEAD(&lta->teardown_head);
1474
1475 rcu_read_lock();
1476
1477 /*
1478 * On a re-registration, we want to kick out the previous registration of
1479 * that pid
1480 */
1481 lttng_ht_add_replace_ulong(ust_app_ht, &lta->pid_n);
1482
1483 /*
1484 * The socket _should_ be unique until _we_ call close. So, a add_unique
1485 * for the ust_app_ht_by_sock is used which asserts fail if the entry was
1486 * already in the table.
1487 */
1488 lttng_ht_add_unique_ulong(ust_app_ht_by_sock, &lta->sock_n);
1489
1490 rcu_read_unlock();
1491
1492 DBG("App registered with pid:%d ppid:%d uid:%d gid:%d sock:%d name:%s"
1493 " (version %d.%d)", lta->pid, lta->ppid, lta->uid, lta->gid,
1494 lta->sock, lta->name, lta->v_major, lta->v_minor);
1495
1496 return 0;
1497 }
1498
1499 /*
1500 * Unregister app by removing it from the global traceable app list and freeing
1501 * the data struct.
1502 *
1503 * The socket is already closed at this point so no close to sock.
1504 */
1505 void ust_app_unregister(int sock)
1506 {
1507 struct ust_app *lta;
1508 struct lttng_ht_node_ulong *node;
1509 struct lttng_ht_iter iter;
1510 struct ust_app_session *ua_sess;
1511 int ret;
1512
1513 rcu_read_lock();
1514
1515 /* Get the node reference for a call_rcu */
1516 lttng_ht_lookup(ust_app_ht_by_sock, (void *)((unsigned long) sock), &iter);
1517 node = lttng_ht_iter_get_node_ulong(&iter);
1518 if (node == NULL) {
1519 ERR("Unable to find app by sock %d", sock);
1520 goto error;
1521 }
1522
1523 lta = caa_container_of(node, struct ust_app, sock_n);
1524
1525 DBG("PID %d unregistering with sock %d", lta->pid, sock);
1526
1527 /* Remove application from PID hash table */
1528 ret = lttng_ht_del(ust_app_ht_by_sock, &iter);
1529 assert(!ret);
1530
1531 /* Assign second node for deletion */
1532 iter.iter.node = &lta->pid_n.node;
1533
1534 /*
1535 * Ignore return value since the node might have been removed before by an
1536 * add replace during app registration because the PID can be reassigned by
1537 * the OS.
1538 */
1539 ret = lttng_ht_del(ust_app_ht, &iter);
1540 if (ret) {
1541 DBG3("Unregister app by PID %d failed. This can happen on pid reuse",
1542 lta->pid);
1543 }
1544
1545 /* Remove sessions so they are not visible during deletion.*/
1546 cds_lfht_for_each_entry(lta->sessions->ht, &iter.iter, ua_sess,
1547 node.node) {
1548 ret = lttng_ht_del(lta->sessions, &iter);
1549 if (ret) {
1550 /* The session was already removed so scheduled for teardown. */
1551 continue;
1552 }
1553
1554 /*
1555 * Add session to list for teardown. This is safe since at this point we
1556 * are the only one using this list.
1557 */
1558 cds_list_add(&ua_sess->teardown_node, &lta->teardown_head);
1559 }
1560
1561 /* Free memory */
1562 call_rcu(&lta->pid_n.head, delete_ust_app_rcu);
1563
1564 error:
1565 rcu_read_unlock();
1566 return;
1567 }
1568
1569 /*
1570 * Return traceable_app_count
1571 */
1572 unsigned long ust_app_list_count(void)
1573 {
1574 unsigned long count;
1575
1576 rcu_read_lock();
1577 count = lttng_ht_get_count(ust_app_ht);
1578 rcu_read_unlock();
1579
1580 return count;
1581 }
1582
1583 /*
1584 * Fill events array with all events name of all registered apps.
1585 */
1586 int ust_app_list_events(struct lttng_event **events)
1587 {
1588 int ret, handle;
1589 size_t nbmem, count = 0;
1590 struct lttng_ht_iter iter;
1591 struct ust_app *app;
1592 struct lttng_event *tmp_event;
1593
1594 nbmem = UST_APP_EVENT_LIST_SIZE;
1595 tmp_event = zmalloc(nbmem * sizeof(struct lttng_event));
1596 if (tmp_event == NULL) {
1597 PERROR("zmalloc ust app events");
1598 ret = -ENOMEM;
1599 goto error;
1600 }
1601
1602 rcu_read_lock();
1603
1604 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
1605 struct lttng_ust_tracepoint_iter uiter;
1606
1607 health_code_update(&health_thread_cmd);
1608
1609 if (!app->compatible) {
1610 /*
1611 * TODO: In time, we should notice the caller of this error by
1612 * telling him that this is a version error.
1613 */
1614 continue;
1615 }
1616 handle = ustctl_tracepoint_list(app->sock);
1617 if (handle < 0) {
1618 ERR("UST app list events getting handle failed for app pid %d",
1619 app->pid);
1620 continue;
1621 }
1622
1623 while ((ret = ustctl_tracepoint_list_get(app->sock, handle,
1624 &uiter)) != -LTTNG_UST_ERR_NOENT) {
1625 health_code_update(&health_thread_cmd);
1626 if (count >= nbmem) {
1627 /* In case the realloc fails, we free the memory */
1628 void *ptr;
1629
1630 DBG2("Reallocating event list from %zu to %zu entries", nbmem,
1631 2 * nbmem);
1632 nbmem *= 2;
1633 ptr = realloc(tmp_event, nbmem * sizeof(struct lttng_event));
1634 if (ptr == NULL) {
1635 PERROR("realloc ust app events");
1636 free(tmp_event);
1637 ret = -ENOMEM;
1638 goto rcu_error;
1639 }
1640 tmp_event = ptr;
1641 }
1642 memcpy(tmp_event[count].name, uiter.name, LTTNG_UST_SYM_NAME_LEN);
1643 tmp_event[count].loglevel = uiter.loglevel;
1644 tmp_event[count].type = (enum lttng_event_type) LTTNG_UST_TRACEPOINT;
1645 tmp_event[count].pid = app->pid;
1646 tmp_event[count].enabled = -1;
1647 count++;
1648 }
1649 }
1650
1651 ret = count;
1652 *events = tmp_event;
1653
1654 DBG2("UST app list events done (%zu events)", count);
1655
1656 rcu_error:
1657 rcu_read_unlock();
1658 error:
1659 health_code_update(&health_thread_cmd);
1660 return ret;
1661 }
1662
1663 /*
1664 * Fill events array with all events name of all registered apps.
1665 */
1666 int ust_app_list_event_fields(struct lttng_event_field **fields)
1667 {
1668 int ret, handle;
1669 size_t nbmem, count = 0;
1670 struct lttng_ht_iter iter;
1671 struct ust_app *app;
1672 struct lttng_event_field *tmp_event;
1673
1674 nbmem = UST_APP_EVENT_LIST_SIZE;
1675 tmp_event = zmalloc(nbmem * sizeof(struct lttng_event_field));
1676 if (tmp_event == NULL) {
1677 PERROR("zmalloc ust app event fields");
1678 ret = -ENOMEM;
1679 goto error;
1680 }
1681
1682 rcu_read_lock();
1683
1684 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
1685 struct lttng_ust_field_iter uiter;
1686
1687 health_code_update(&health_thread_cmd);
1688
1689 if (!app->compatible) {
1690 /*
1691 * TODO: In time, we should notice the caller of this error by
1692 * telling him that this is a version error.
1693 */
1694 continue;
1695 }
1696 handle = ustctl_tracepoint_field_list(app->sock);
1697 if (handle < 0) {
1698 ERR("UST app list event fields getting handle failed for app pid %d",
1699 app->pid);
1700 continue;
1701 }
1702
1703 while ((ret = ustctl_tracepoint_field_list_get(app->sock, handle,
1704 &uiter)) != -LTTNG_UST_ERR_NOENT) {
1705 health_code_update(&health_thread_cmd);
1706 if (count >= nbmem) {
1707 /* In case the realloc fails, we free the memory */
1708 void *ptr;
1709
1710 DBG2("Reallocating event field list from %zu to %zu entries", nbmem,
1711 2 * nbmem);
1712 nbmem *= 2;
1713 ptr = realloc(tmp_event, nbmem * sizeof(struct lttng_event_field));
1714 if (ptr == NULL) {
1715 PERROR("realloc ust app event fields");
1716 free(tmp_event);
1717 ret = -ENOMEM;
1718 goto rcu_error;
1719 }
1720 tmp_event = ptr;
1721 }
1722
1723 memcpy(tmp_event[count].field_name, uiter.field_name, LTTNG_UST_SYM_NAME_LEN);
1724 tmp_event[count].type = uiter.type;
1725 tmp_event[count].nowrite = uiter.nowrite;
1726
1727 memcpy(tmp_event[count].event.name, uiter.event_name, LTTNG_UST_SYM_NAME_LEN);
1728 tmp_event[count].event.loglevel = uiter.loglevel;
1729 tmp_event[count].event.type = LTTNG_UST_TRACEPOINT;
1730 tmp_event[count].event.pid = app->pid;
1731 tmp_event[count].event.enabled = -1;
1732 count++;
1733 }
1734 }
1735
1736 ret = count;
1737 *fields = tmp_event;
1738
1739 DBG2("UST app list event fields done (%zu events)", count);
1740
1741 rcu_error:
1742 rcu_read_unlock();
1743 error:
1744 health_code_update(&health_thread_cmd);
1745 return ret;
1746 }
1747
1748 /*
1749 * Free and clean all traceable apps of the global list.
1750 */
1751 void ust_app_clean_list(void)
1752 {
1753 int ret;
1754 struct ust_app *app;
1755 struct lttng_ht_iter iter;
1756
1757 DBG2("UST app cleaning registered apps hash table");
1758
1759 rcu_read_lock();
1760
1761 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
1762 ret = lttng_ht_del(ust_app_ht, &iter);
1763 assert(!ret);
1764 call_rcu(&app->pid_n.head, delete_ust_app_rcu);
1765 }
1766
1767 /* Cleanup socket hash table */
1768 cds_lfht_for_each_entry(ust_app_ht_by_sock->ht, &iter.iter, app,
1769 sock_n.node) {
1770 ret = lttng_ht_del(ust_app_ht_by_sock, &iter);
1771 assert(!ret);
1772 }
1773
1774 /* Destroy is done only when the ht is empty */
1775 lttng_ht_destroy(ust_app_ht);
1776 lttng_ht_destroy(ust_app_ht_by_sock);
1777
1778 rcu_read_unlock();
1779 }
1780
1781 /*
1782 * Init UST app hash table.
1783 */
1784 void ust_app_ht_alloc(void)
1785 {
1786 ust_app_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
1787 ust_app_ht_by_sock = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
1788 }
1789
1790 /*
1791 * For a specific UST session, disable the channel for all registered apps.
1792 */
1793 int ust_app_disable_channel_glb(struct ltt_ust_session *usess,
1794 struct ltt_ust_channel *uchan)
1795 {
1796 int ret = 0;
1797 struct lttng_ht_iter iter;
1798 struct lttng_ht_node_str *ua_chan_node;
1799 struct ust_app *app;
1800 struct ust_app_session *ua_sess;
1801 struct ust_app_channel *ua_chan;
1802
1803 if (usess == NULL || uchan == NULL) {
1804 ERR("Disabling UST global channel with NULL values");
1805 ret = -1;
1806 goto error;
1807 }
1808
1809 DBG2("UST app disabling channel %s from global domain for session id %d",
1810 uchan->name, usess->id);
1811
1812 rcu_read_lock();
1813
1814 /* For every registered applications */
1815 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
1816 struct lttng_ht_iter uiter;
1817 if (!app->compatible) {
1818 /*
1819 * TODO: In time, we should notice the caller of this error by
1820 * telling him that this is a version error.
1821 */
1822 continue;
1823 }
1824 ua_sess = lookup_session_by_app(usess, app);
1825 if (ua_sess == NULL) {
1826 continue;
1827 }
1828
1829 /* Get channel */
1830 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
1831 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
1832 /* If the session if found for the app, the channel must be there */
1833 assert(ua_chan_node);
1834
1835 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
1836 /* The channel must not be already disabled */
1837 assert(ua_chan->enabled == 1);
1838
1839 /* Disable channel onto application */
1840 ret = disable_ust_app_channel(ua_sess, ua_chan, app);
1841 if (ret < 0) {
1842 /* XXX: We might want to report this error at some point... */
1843 continue;
1844 }
1845 }
1846
1847 rcu_read_unlock();
1848
1849 error:
1850 return ret;
1851 }
1852
1853 /*
1854 * For a specific UST session, enable the channel for all registered apps.
1855 */
1856 int ust_app_enable_channel_glb(struct ltt_ust_session *usess,
1857 struct ltt_ust_channel *uchan)
1858 {
1859 int ret = 0;
1860 struct lttng_ht_iter iter;
1861 struct ust_app *app;
1862 struct ust_app_session *ua_sess;
1863
1864 if (usess == NULL || uchan == NULL) {
1865 ERR("Adding UST global channel to NULL values");
1866 ret = -1;
1867 goto error;
1868 }
1869
1870 DBG2("UST app enabling channel %s to global domain for session id %d",
1871 uchan->name, usess->id);
1872
1873 rcu_read_lock();
1874
1875 /* For every registered applications */
1876 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
1877 if (!app->compatible) {
1878 /*
1879 * TODO: In time, we should notice the caller of this error by
1880 * telling him that this is a version error.
1881 */
1882 continue;
1883 }
1884 ua_sess = lookup_session_by_app(usess, app);
1885 if (ua_sess == NULL) {
1886 continue;
1887 }
1888
1889 /* Enable channel onto application */
1890 ret = enable_ust_app_channel(ua_sess, uchan, app);
1891 if (ret < 0) {
1892 /* XXX: We might want to report this error at some point... */
1893 continue;
1894 }
1895 }
1896
1897 rcu_read_unlock();
1898
1899 error:
1900 return ret;
1901 }
1902
1903 /*
1904 * Disable an event in a channel and for a specific session.
1905 */
1906 int ust_app_disable_event_glb(struct ltt_ust_session *usess,
1907 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent)
1908 {
1909 int ret = 0;
1910 struct lttng_ht_iter iter, uiter;
1911 struct lttng_ht_node_str *ua_chan_node, *ua_event_node;
1912 struct ust_app *app;
1913 struct ust_app_session *ua_sess;
1914 struct ust_app_channel *ua_chan;
1915 struct ust_app_event *ua_event;
1916
1917 DBG("UST app disabling event %s for all apps in channel "
1918 "%s for session id %d", uevent->attr.name, uchan->name, usess->id);
1919
1920 rcu_read_lock();
1921
1922 /* For all registered applications */
1923 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
1924 if (!app->compatible) {
1925 /*
1926 * TODO: In time, we should notice the caller of this error by
1927 * telling him that this is a version error.
1928 */
1929 continue;
1930 }
1931 ua_sess = lookup_session_by_app(usess, app);
1932 if (ua_sess == NULL) {
1933 /* Next app */
1934 continue;
1935 }
1936
1937 /* Lookup channel in the ust app session */
1938 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
1939 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
1940 if (ua_chan_node == NULL) {
1941 DBG2("Channel %s not found in session id %d for app pid %d."
1942 "Skipping", uchan->name, usess->id, app->pid);
1943 continue;
1944 }
1945 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
1946
1947 lttng_ht_lookup(ua_chan->events, (void *)uevent->attr.name, &uiter);
1948 ua_event_node = lttng_ht_iter_get_node_str(&uiter);
1949 if (ua_event_node == NULL) {
1950 DBG2("Event %s not found in channel %s for app pid %d."
1951 "Skipping", uevent->attr.name, uchan->name, app->pid);
1952 continue;
1953 }
1954 ua_event = caa_container_of(ua_event_node, struct ust_app_event, node);
1955
1956 ret = disable_ust_app_event(ua_sess, ua_event, app);
1957 if (ret < 0) {
1958 /* XXX: Report error someday... */
1959 continue;
1960 }
1961 }
1962
1963 rcu_read_unlock();
1964
1965 return ret;
1966 }
1967
1968 /*
1969 * For a specific UST session and UST channel, the event for all
1970 * registered apps.
1971 */
1972 int ust_app_disable_all_event_glb(struct ltt_ust_session *usess,
1973 struct ltt_ust_channel *uchan)
1974 {
1975 int ret = 0;
1976 struct lttng_ht_iter iter, uiter;
1977 struct lttng_ht_node_str *ua_chan_node;
1978 struct ust_app *app;
1979 struct ust_app_session *ua_sess;
1980 struct ust_app_channel *ua_chan;
1981 struct ust_app_event *ua_event;
1982
1983 DBG("UST app disabling all event for all apps in channel "
1984 "%s for session id %d", uchan->name, usess->id);
1985
1986 rcu_read_lock();
1987
1988 /* For all registered applications */
1989 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
1990 if (!app->compatible) {
1991 /*
1992 * TODO: In time, we should notice the caller of this error by
1993 * telling him that this is a version error.
1994 */
1995 continue;
1996 }
1997 ua_sess = lookup_session_by_app(usess, app);
1998 if (!ua_sess) {
1999 /* The application has problem or is probably dead. */
2000 continue;
2001 }
2002
2003 /* Lookup channel in the ust app session */
2004 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
2005 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
2006 /* If the channel is not found, there is a code flow error */
2007 assert(ua_chan_node);
2008
2009 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
2010
2011 /* Disable each events of channel */
2012 cds_lfht_for_each_entry(ua_chan->events->ht, &uiter.iter, ua_event,
2013 node.node) {
2014 ret = disable_ust_app_event(ua_sess, ua_event, app);
2015 if (ret < 0) {
2016 /* XXX: Report error someday... */
2017 continue;
2018 }
2019 }
2020 }
2021
2022 rcu_read_unlock();
2023
2024 return ret;
2025 }
2026
2027 /*
2028 * For a specific UST session, create the channel for all registered apps.
2029 */
2030 int ust_app_create_channel_glb(struct ltt_ust_session *usess,
2031 struct ltt_ust_channel *uchan)
2032 {
2033 int ret = 0;
2034 struct lttng_ht_iter iter;
2035 struct ust_app *app;
2036 struct ust_app_session *ua_sess;
2037
2038 /* Very wrong code flow */
2039 assert(usess);
2040 assert(uchan);
2041
2042 DBG2("UST app adding channel %s to global domain for session id %d",
2043 uchan->name, usess->id);
2044
2045 rcu_read_lock();
2046
2047 /* For every registered applications */
2048 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
2049 if (!app->compatible) {
2050 /*
2051 * TODO: In time, we should notice the caller of this error by
2052 * telling him that this is a version error.
2053 */
2054 continue;
2055 }
2056 /*
2057 * Create session on the tracer side and add it to app session HT. Note
2058 * that if session exist, it will simply return a pointer to the ust
2059 * app session.
2060 */
2061 ua_sess = create_ust_app_session(usess, app);
2062 if (ua_sess == NULL) {
2063 /* The malloc() failed. */
2064 ret = -ENOMEM;
2065 goto error_rcu_unlock;
2066 } else if (ua_sess == (void *) -1UL) {
2067 /*
2068 * The application's socket is not valid. Either a bad socket or a
2069 * timeout on it. We can't inform yet the caller that for a
2070 * specific app, the session failed so we continue here.
2071 */
2072 continue;
2073 }
2074
2075 /* Create channel onto application. We don't need the chan ref. */
2076 ret = create_ust_app_channel(ua_sess, uchan, app, NULL);
2077 if (ret < 0 && ret == -ENOMEM) {
2078 /* No more memory is a fatal error. Stop right now. */
2079 goto error_rcu_unlock;
2080 }
2081 }
2082
2083 error_rcu_unlock:
2084 rcu_read_unlock();
2085 return ret;
2086 }
2087
2088 /*
2089 * Enable event for a specific session and channel on the tracer.
2090 */
2091 int ust_app_enable_event_glb(struct ltt_ust_session *usess,
2092 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent)
2093 {
2094 int ret = 0;
2095 struct lttng_ht_iter iter, uiter;
2096 struct lttng_ht_node_str *ua_chan_node;
2097 struct ust_app *app;
2098 struct ust_app_session *ua_sess;
2099 struct ust_app_channel *ua_chan;
2100 struct ust_app_event *ua_event;
2101
2102 DBG("UST app enabling event %s for all apps for session id %d",
2103 uevent->attr.name, usess->id);
2104
2105 /*
2106 * NOTE: At this point, this function is called only if the session and
2107 * channel passed are already created for all apps. and enabled on the
2108 * tracer also.
2109 */
2110
2111 rcu_read_lock();
2112
2113 /* For all registered applications */
2114 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
2115 if (!app->compatible) {
2116 /*
2117 * TODO: In time, we should notice the caller of this error by
2118 * telling him that this is a version error.
2119 */
2120 continue;
2121 }
2122 ua_sess = lookup_session_by_app(usess, app);
2123 if (!ua_sess) {
2124 /* The application has problem or is probably dead. */
2125 continue;
2126 }
2127
2128 /* Lookup channel in the ust app session */
2129 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
2130 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
2131 /* If the channel is not found, there is a code flow error */
2132 assert(ua_chan_node);
2133
2134 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
2135
2136 /* Get event node */
2137 ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name,
2138 uevent->filter, uevent->attr.loglevel);
2139 if (ua_event == NULL) {
2140 DBG3("UST app enable event %s not found for app PID %d."
2141 "Skipping app", uevent->attr.name, app->pid);
2142 continue;
2143 }
2144
2145 ret = enable_ust_app_event(ua_sess, ua_event, app);
2146 if (ret < 0) {
2147 goto error;
2148 }
2149 }
2150
2151 error:
2152 rcu_read_unlock();
2153 return ret;
2154 }
2155
2156 /*
2157 * For a specific existing UST session and UST channel, creates the event for
2158 * all registered apps.
2159 */
2160 int ust_app_create_event_glb(struct ltt_ust_session *usess,
2161 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent)
2162 {
2163 int ret = 0;
2164 struct lttng_ht_iter iter, uiter;
2165 struct lttng_ht_node_str *ua_chan_node;
2166 struct ust_app *app;
2167 struct ust_app_session *ua_sess;
2168 struct ust_app_channel *ua_chan;
2169
2170 DBG("UST app creating event %s for all apps for session id %d",
2171 uevent->attr.name, usess->id);
2172
2173 rcu_read_lock();
2174
2175 /* For all registered applications */
2176 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
2177 if (!app->compatible) {
2178 /*
2179 * TODO: In time, we should notice the caller of this error by
2180 * telling him that this is a version error.
2181 */
2182 continue;
2183 }
2184 ua_sess = lookup_session_by_app(usess, app);
2185 if (!ua_sess) {
2186 /* The application has problem or is probably dead. */
2187 continue;
2188 }
2189
2190 /* Lookup channel in the ust app session */
2191 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
2192 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
2193 /* If the channel is not found, there is a code flow error */
2194 assert(ua_chan_node);
2195
2196 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
2197
2198 ret = create_ust_app_event(ua_sess, ua_chan, uevent, app);
2199 if (ret < 0) {
2200 if (ret != -LTTNG_UST_ERR_EXIST) {
2201 /* Possible value at this point: -ENOMEM. If so, we stop! */
2202 break;
2203 }
2204 DBG2("UST app event %s already exist on app PID %d",
2205 uevent->attr.name, app->pid);
2206 continue;
2207 }
2208 }
2209
2210 rcu_read_unlock();
2211
2212 return ret;
2213 }
2214
2215 /*
2216 * Start tracing for a specific UST session and app.
2217 */
2218 int ust_app_start_trace(struct ltt_ust_session *usess, struct ust_app *app)
2219 {
2220 int ret = 0;
2221 struct lttng_ht_iter iter;
2222 struct ust_app_session *ua_sess;
2223 struct ust_app_channel *ua_chan;
2224 struct ltt_ust_stream *ustream;
2225 struct consumer_socket *socket;
2226
2227 DBG("Starting tracing for ust app pid %d", app->pid);
2228
2229 rcu_read_lock();
2230
2231 if (!app->compatible) {
2232 goto end;
2233 }
2234
2235 ua_sess = lookup_session_by_app(usess, app);
2236 if (ua_sess == NULL) {
2237 /* The session is in teardown process. Ignore and continue. */
2238 goto end;
2239 }
2240
2241 /* Upon restart, we skip the setup, already done */
2242 if (ua_sess->started) {
2243 goto skip_setup;
2244 }
2245
2246 /* Create directories if consumer is LOCAL and has a path defined. */
2247 if (usess->consumer->type == CONSUMER_DST_LOCAL &&
2248 strlen(usess->consumer->dst.trace_path) > 0) {
2249 ret = run_as_mkdir_recursive(usess->consumer->dst.trace_path,
2250 S_IRWXU | S_IRWXG, usess->uid, usess->gid);
2251 if (ret < 0) {
2252 if (ret != -EEXIST) {
2253 ERR("Trace directory creation error");
2254 ret = -1;
2255 goto error_rcu_unlock;
2256 }
2257 }
2258 }
2259
2260 ret = create_ust_app_metadata(ua_sess, usess->pathname, app);
2261 if (ret < 0) {
2262 ret = LTTNG_ERR_UST_META_FAIL;
2263 goto error_rcu_unlock;
2264 }
2265
2266 /* For each channel */
2267 cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
2268 node.node) {
2269 /* Create all streams */
2270 while (1) {
2271 /* Create UST stream */
2272 ustream = zmalloc(sizeof(*ustream));
2273 if (ustream == NULL) {
2274 PERROR("zmalloc ust stream");
2275 goto error_rcu_unlock;
2276 }
2277
2278 /* We are going to receive 2 fds, we need to reserve them. */
2279 ret = lttng_fd_get(LTTNG_FD_APPS, 2);
2280 if (ret < 0) {
2281 ERR("Exhausted number of available FD upon stream create");
2282 free(ustream);
2283 goto error_rcu_unlock;
2284 }
2285
2286 health_code_update(&health_thread_cmd);
2287
2288 ret = ustctl_create_stream(app->sock, ua_chan->obj,
2289 &ustream->obj);
2290 if (ret < 0) {
2291 /* Got all streams */
2292 lttng_fd_put(LTTNG_FD_APPS, 2);
2293 free(ustream);
2294 ret = LTTNG_ERR_UST_STREAM_FAIL;
2295 break;
2296 }
2297 ustream->handle = ustream->obj->handle;
2298
2299 health_code_update(&health_thread_cmd);
2300
2301 /* Order is important */
2302 cds_list_add_tail(&ustream->list, &ua_chan->streams.head);
2303 ret = snprintf(ustream->name, sizeof(ustream->name), "%s_%u",
2304 ua_chan->name, ua_chan->streams.count);
2305 ua_chan->streams.count++;
2306 if (ret < 0) {
2307 PERROR("asprintf UST create stream");
2308 /*
2309 * XXX what should we do here with the
2310 * stream ?
2311 */
2312 continue;
2313 }
2314 DBG2("UST stream %d ready (handle: %d)", ua_chan->streams.count,
2315 ustream->handle);
2316 }
2317
2318 health_code_update(&health_thread_cmd);
2319 }
2320
2321 switch (app->bits_per_long) {
2322 case 64:
2323 socket = consumer_find_socket(uatomic_read(&ust_consumerd64_fd),
2324 usess->consumer);
2325 if (socket == NULL) {
2326 goto skip_setup;
2327 }
2328 break;
2329 case 32:
2330 socket = consumer_find_socket(uatomic_read(&ust_consumerd32_fd),
2331 usess->consumer);
2332 if (socket == NULL) {
2333 goto skip_setup;
2334 }
2335 break;
2336 default:
2337 ret = -EINVAL;
2338 goto error_rcu_unlock;
2339 }
2340
2341 /* Setup UST consumer socket and send fds to it */
2342 ret = ust_consumer_send_session(ua_sess, usess->consumer, socket);
2343 if (ret < 0) {
2344 goto error_rcu_unlock;
2345 }
2346
2347 health_code_update(&health_thread_cmd);
2348
2349 skip_setup:
2350 /* This start the UST tracing */
2351 ret = ustctl_start_session(app->sock, ua_sess->handle);
2352 if (ret < 0) {
2353 ERR("Error starting tracing for app pid: %d (ret: %d)", app->pid, ret);
2354 goto error_rcu_unlock;
2355 }
2356
2357 /* Indicate that the session has been started once */
2358 ua_sess->started = 1;
2359
2360 health_code_update(&health_thread_cmd);
2361
2362 /* Quiescent wait after starting trace */
2363 ustctl_wait_quiescent(app->sock);
2364
2365 end:
2366 rcu_read_unlock();
2367 health_code_update(&health_thread_cmd);
2368 return 0;
2369
2370 error_rcu_unlock:
2371 rcu_read_unlock();
2372 health_code_update(&health_thread_cmd);
2373 return -1;
2374 }
2375
2376 /*
2377 * Stop tracing for a specific UST session and app.
2378 */
2379 int ust_app_stop_trace(struct ltt_ust_session *usess, struct ust_app *app)
2380 {
2381 int ret = 0;
2382 struct lttng_ht_iter iter;
2383 struct ust_app_session *ua_sess;
2384 struct ust_app_channel *ua_chan;
2385
2386 DBG("Stopping tracing for ust app pid %d", app->pid);
2387
2388 rcu_read_lock();
2389
2390 if (!app->compatible) {
2391 goto end;
2392 }
2393
2394 ua_sess = lookup_session_by_app(usess, app);
2395 if (ua_sess == NULL) {
2396 goto end;
2397 }
2398
2399 /*
2400 * If started = 0, it means that stop trace has been called for a session
2401 * that was never started. It's possible since we can have a fail start
2402 * from either the application manager thread or the command thread. Simply
2403 * indicate that this is a stop error.
2404 */
2405 if (!ua_sess->started) {
2406 goto error_rcu_unlock;
2407 }
2408
2409 health_code_update(&health_thread_cmd);
2410
2411 /* This inhibits UST tracing */
2412 ret = ustctl_stop_session(app->sock, ua_sess->handle);
2413 if (ret < 0) {
2414 ERR("Error stopping tracing for app pid: %d (ret: %d)", app->pid, ret);
2415 goto error_rcu_unlock;
2416 }
2417
2418 health_code_update(&health_thread_cmd);
2419
2420 /* Quiescent wait after stopping trace */
2421 ustctl_wait_quiescent(app->sock);
2422
2423 health_code_update(&health_thread_cmd);
2424
2425 /* Flushing buffers */
2426 cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
2427 node.node) {
2428 health_code_update(&health_thread_cmd);
2429 ret = ustctl_sock_flush_buffer(app->sock, ua_chan->obj);
2430 if (ret < 0) {
2431 ERR("UST app PID %d channel %s flush failed with ret %d",
2432 app->pid, ua_chan->name, ret);
2433 /* Continuing flushing all buffers */
2434 continue;
2435 }
2436 }
2437
2438 health_code_update(&health_thread_cmd);
2439
2440 /* Flush all buffers before stopping */
2441 ret = ustctl_sock_flush_buffer(app->sock, ua_sess->metadata->obj);
2442 if (ret < 0) {
2443 ERR("UST app PID %d metadata flush failed with ret %d", app->pid,
2444 ret);
2445 }
2446
2447 end:
2448 rcu_read_unlock();
2449 health_code_update(&health_thread_cmd);
2450 return 0;
2451
2452 error_rcu_unlock:
2453 rcu_read_unlock();
2454 health_code_update(&health_thread_cmd);
2455 return -1;
2456 }
2457
2458 /*
2459 * Destroy a specific UST session in apps.
2460 */
2461 static int destroy_trace(struct ltt_ust_session *usess, struct ust_app *app)
2462 {
2463 struct ust_app_session *ua_sess;
2464 struct lttng_ust_object_data obj;
2465 struct lttng_ht_iter iter;
2466 struct lttng_ht_node_ulong *node;
2467 int ret;
2468
2469 DBG("Destroy tracing for ust app pid %d", app->pid);
2470
2471 rcu_read_lock();
2472
2473 if (!app->compatible) {
2474 goto end;
2475 }
2476
2477 __lookup_session_by_app(usess, app, &iter);
2478 node = lttng_ht_iter_get_node_ulong(&iter);
2479 if (node == NULL) {
2480 /* Session is being or is deleted. */
2481 goto end;
2482 }
2483 ua_sess = caa_container_of(node, struct ust_app_session, node);
2484 ret = lttng_ht_del(app->sessions, &iter);
2485 if (ret) {
2486 /* Already scheduled for teardown. */
2487 goto end;
2488 }
2489
2490 obj.handle = ua_sess->handle;
2491 obj.shm_fd = -1;
2492 obj.wait_fd = -1;
2493 obj.memory_map_size = 0;
2494 health_code_update(&health_thread_cmd);
2495 ustctl_release_object(app->sock, &obj);
2496
2497 health_code_update(&health_thread_cmd);
2498 delete_ust_app_session(app->sock, ua_sess);
2499
2500 /* Quiescent wait after stopping trace */
2501 ustctl_wait_quiescent(app->sock);
2502
2503 end:
2504 rcu_read_unlock();
2505 health_code_update(&health_thread_cmd);
2506 return 0;
2507 }
2508
2509 /*
2510 * Start tracing for the UST session.
2511 */
2512 int ust_app_start_trace_all(struct ltt_ust_session *usess)
2513 {
2514 int ret = 0;
2515 struct lttng_ht_iter iter;
2516 struct ust_app *app;
2517
2518 DBG("Starting all UST traces");
2519
2520 rcu_read_lock();
2521
2522 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
2523 ret = ust_app_start_trace(usess, app);
2524 if (ret < 0) {
2525 /* Continue to next apps even on error */
2526 continue;
2527 }
2528 }
2529
2530 rcu_read_unlock();
2531
2532 return 0;
2533 }
2534
2535 /*
2536 * Start tracing for the UST session.
2537 */
2538 int ust_app_stop_trace_all(struct ltt_ust_session *usess)
2539 {
2540 int ret = 0;
2541 struct lttng_ht_iter iter;
2542 struct ust_app *app;
2543
2544 DBG("Stopping all UST traces");
2545
2546 rcu_read_lock();
2547
2548 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
2549 ret = ust_app_stop_trace(usess, app);
2550 if (ret < 0) {
2551 /* Continue to next apps even on error */
2552 continue;
2553 }
2554 }
2555
2556 rcu_read_unlock();
2557
2558 return 0;
2559 }
2560
2561 /*
2562 * Destroy app UST session.
2563 */
2564 int ust_app_destroy_trace_all(struct ltt_ust_session *usess)
2565 {
2566 int ret = 0;
2567 struct lttng_ht_iter iter;
2568 struct ust_app *app;
2569
2570 DBG("Destroy all UST traces");
2571
2572 rcu_read_lock();
2573
2574 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
2575 ret = destroy_trace(usess, app);
2576 if (ret < 0) {
2577 /* Continue to next apps even on error */
2578 continue;
2579 }
2580 }
2581
2582 rcu_read_unlock();
2583
2584 return 0;
2585 }
2586
2587 /*
2588 * Add channels/events from UST global domain to registered apps at sock.
2589 */
2590 void ust_app_global_update(struct ltt_ust_session *usess, int sock)
2591 {
2592 int ret = 0;
2593 struct lttng_ht_iter iter, uiter, iter_ctx;
2594 struct ust_app *app;
2595 struct ust_app_session *ua_sess;
2596 struct ust_app_channel *ua_chan;
2597 struct ust_app_event *ua_event;
2598 struct ust_app_ctx *ua_ctx;
2599
2600 assert(usess);
2601
2602 DBG2("UST app global update for app sock %d for session id %d", sock,
2603 usess->id);
2604
2605 rcu_read_lock();
2606
2607 app = find_app_by_sock(sock);
2608 if (app == NULL) {
2609 ERR("Failed to update app sock %d", sock);
2610 goto error;
2611 }
2612
2613 if (!app->compatible) {
2614 goto error;
2615 }
2616
2617 ua_sess = create_ust_app_session(usess, app);
2618 if (ua_sess == NULL || ua_sess == (void *) -1UL) {
2619 /* Tracer is gone for this session and has been freed */
2620 goto error;
2621 }
2622
2623 /*
2624 * We can iterate safely here over all UST app session sicne the create ust
2625 * app session above made a shadow copy of the UST global domain from the
2626 * ltt ust session.
2627 */
2628 cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
2629 node.node) {
2630 ret = create_ust_channel(app, ua_sess, ua_chan);
2631 if (ret < 0) {
2632 /* FIXME: Should we quit here or continue... */
2633 continue;
2634 }
2635
2636 cds_lfht_for_each_entry(ua_chan->ctx->ht, &iter_ctx.iter, ua_ctx,
2637 node.node) {
2638 ret = create_ust_channel_context(ua_chan, ua_ctx, app);
2639 if (ret < 0) {
2640 /* FIXME: Should we quit here or continue... */
2641 continue;
2642 }
2643 }
2644
2645
2646 /* For each events */
2647 cds_lfht_for_each_entry(ua_chan->events->ht, &uiter.iter, ua_event,
2648 node.node) {
2649 ret = create_ust_event(app, ua_sess, ua_chan, ua_event);
2650 if (ret < 0) {
2651 /* FIXME: Should we quit here or continue... */
2652 continue;
2653 }
2654 }
2655 }
2656
2657 if (usess->start_trace) {
2658 ret = ust_app_start_trace(usess, app);
2659 if (ret < 0) {
2660 goto error;
2661 }
2662
2663 DBG2("UST trace started for app pid %d", app->pid);
2664 }
2665
2666 error:
2667 rcu_read_unlock();
2668 return;
2669 }
2670
2671 /*
2672 * Add context to a specific channel for global UST domain.
2673 */
2674 int ust_app_add_ctx_channel_glb(struct ltt_ust_session *usess,
2675 struct ltt_ust_channel *uchan, struct ltt_ust_context *uctx)
2676 {
2677 int ret = 0;
2678 struct lttng_ht_node_str *ua_chan_node;
2679 struct lttng_ht_iter iter, uiter;
2680 struct ust_app_channel *ua_chan = NULL;
2681 struct ust_app_session *ua_sess;
2682 struct ust_app *app;
2683
2684 rcu_read_lock();
2685
2686 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
2687 if (!app->compatible) {
2688 /*
2689 * TODO: In time, we should notice the caller of this error by
2690 * telling him that this is a version error.
2691 */
2692 continue;
2693 }
2694 ua_sess = lookup_session_by_app(usess, app);
2695 if (ua_sess == NULL) {
2696 continue;
2697 }
2698
2699 /* Lookup channel in the ust app session */
2700 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
2701 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
2702 if (ua_chan_node == NULL) {
2703 continue;
2704 }
2705 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel,
2706 node);
2707
2708 ret = create_ust_app_channel_context(ua_sess, ua_chan, &uctx->ctx, app);
2709 if (ret < 0) {
2710 continue;
2711 }
2712 }
2713
2714 rcu_read_unlock();
2715 return ret;
2716 }
2717
2718 /*
2719 * Enable event for a channel from a UST session for a specific PID.
2720 */
2721 int ust_app_enable_event_pid(struct ltt_ust_session *usess,
2722 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent, pid_t pid)
2723 {
2724 int ret = 0;
2725 struct lttng_ht_iter iter;
2726 struct lttng_ht_node_str *ua_chan_node;
2727 struct ust_app *app;
2728 struct ust_app_session *ua_sess;
2729 struct ust_app_channel *ua_chan;
2730 struct ust_app_event *ua_event;
2731
2732 DBG("UST app enabling event %s for PID %d", uevent->attr.name, pid);
2733
2734 rcu_read_lock();
2735
2736 app = ust_app_find_by_pid(pid);
2737 if (app == NULL) {
2738 ERR("UST app enable event per PID %d not found", pid);
2739 ret = -1;
2740 goto error;
2741 }
2742
2743 if (!app->compatible) {
2744 ret = 0;
2745 goto error;
2746 }
2747
2748 ua_sess = lookup_session_by_app(usess, app);
2749 if (!ua_sess) {
2750 /* The application has problem or is probably dead. */
2751 goto error;
2752 }
2753
2754 /* Lookup channel in the ust app session */
2755 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
2756 ua_chan_node = lttng_ht_iter_get_node_str(&iter);
2757 /* If the channel is not found, there is a code flow error */
2758 assert(ua_chan_node);
2759
2760 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
2761
2762 ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name,
2763 uevent->filter, uevent->attr.loglevel);
2764 if (ua_event == NULL) {
2765 ret = create_ust_app_event(ua_sess, ua_chan, uevent, app);
2766 if (ret < 0) {
2767 goto error;
2768 }
2769 } else {
2770 ret = enable_ust_app_event(ua_sess, ua_event, app);
2771 if (ret < 0) {
2772 goto error;
2773 }
2774 }
2775
2776 error:
2777 rcu_read_unlock();
2778 return ret;
2779 }
2780
2781 /*
2782 * Disable event for a channel from a UST session for a specific PID.
2783 */
2784 int ust_app_disable_event_pid(struct ltt_ust_session *usess,
2785 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent, pid_t pid)
2786 {
2787 int ret = 0;
2788 struct lttng_ht_iter iter;
2789 struct lttng_ht_node_str *ua_chan_node, *ua_event_node;
2790 struct ust_app *app;
2791 struct ust_app_session *ua_sess;
2792 struct ust_app_channel *ua_chan;
2793 struct ust_app_event *ua_event;
2794
2795 DBG("UST app disabling event %s for PID %d", uevent->attr.name, pid);
2796
2797 rcu_read_lock();
2798
2799 app = ust_app_find_by_pid(pid);
2800 if (app == NULL) {
2801 ERR("UST app disable event per PID %d not found", pid);
2802 ret = -1;
2803 goto error;
2804 }
2805
2806 if (!app->compatible) {
2807 ret = 0;
2808 goto error;
2809 }
2810
2811 ua_sess = lookup_session_by_app(usess, app);
2812 if (!ua_sess) {
2813 /* The application has problem or is probably dead. */
2814 goto error;
2815 }
2816
2817 /* Lookup channel in the ust app session */
2818 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
2819 ua_chan_node = lttng_ht_iter_get_node_str(&iter);
2820 if (ua_chan_node == NULL) {
2821 /* Channel does not exist, skip disabling */
2822 goto error;
2823 }
2824 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
2825
2826 lttng_ht_lookup(ua_chan->events, (void *)uevent->attr.name, &iter);
2827 ua_event_node = lttng_ht_iter_get_node_str(&iter);
2828 if (ua_event_node == NULL) {
2829 /* Event does not exist, skip disabling */
2830 goto error;
2831 }
2832 ua_event = caa_container_of(ua_event_node, struct ust_app_event, node);
2833
2834 ret = disable_ust_app_event(ua_sess, ua_event, app);
2835 if (ret < 0) {
2836 goto error;
2837 }
2838
2839 error:
2840 rcu_read_unlock();
2841 return ret;
2842 }
2843
2844 /*
2845 * Validate version of UST apps and set the compatible bit.
2846 */
2847 int ust_app_validate_version(int sock)
2848 {
2849 int ret;
2850 struct ust_app *app;
2851
2852 rcu_read_lock();
2853
2854 app = find_app_by_sock(sock);
2855 assert(app);
2856
2857 health_code_update(&health_thread_cmd);
2858
2859 ret = ustctl_tracer_version(sock, &app->version);
2860 if (ret < 0) {
2861 goto error;
2862 }
2863
2864 /* Validate version */
2865 if (app->version.major != UST_APP_MAJOR_VERSION) {
2866 goto error;
2867 }
2868
2869 DBG2("UST app PID %d is compatible with internal major version %d "
2870 "(supporting == %d)", app->pid, app->version.major,
2871 UST_APP_MAJOR_VERSION);
2872 app->compatible = 1;
2873 rcu_read_unlock();
2874 health_code_update(&health_thread_cmd);
2875 return 0;
2876
2877 error:
2878 DBG2("UST app PID %d is not compatible with internal major version %d "
2879 "(supporting == %d)", app->pid, app->version.major,
2880 UST_APP_MAJOR_VERSION);
2881 app->compatible = 0;
2882 rcu_read_unlock();
2883 health_code_update(&health_thread_cmd);
2884 return -1;
2885 }
2886
2887 /*
2888 * Calibrate registered applications.
2889 */
2890 int ust_app_calibrate_glb(struct lttng_ust_calibrate *calibrate)
2891 {
2892 int ret = 0;
2893 struct lttng_ht_iter iter;
2894 struct ust_app *app;
2895
2896 rcu_read_lock();
2897
2898 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
2899 if (!app->compatible) {
2900 /*
2901 * TODO: In time, we should notice the caller of this error by
2902 * telling him that this is a version error.
2903 */
2904 continue;
2905 }
2906
2907 health_code_update(&health_thread_cmd);
2908
2909 ret = ustctl_calibrate(app->sock, calibrate);
2910 if (ret < 0) {
2911 switch (ret) {
2912 case -ENOSYS:
2913 /* Means that it's not implemented on the tracer side. */
2914 ret = 0;
2915 break;
2916 default:
2917 /* TODO: Report error to user */
2918 DBG2("Calibrate app PID %d returned with error %d",
2919 app->pid, ret);
2920 break;
2921 }
2922 }
2923 }
2924
2925 DBG("UST app global domain calibration finished");
2926
2927 rcu_read_unlock();
2928
2929 health_code_update(&health_thread_cmd);
2930
2931 return ret;
2932 }
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