e1d0c40e9cf03e34b935a171b1ca8d67686f55f5
[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 int ret;
1042 struct ust_app_session *ua_sess;
1043
1044 health_code_update(&health_thread_cmd);
1045
1046 ua_sess = lookup_session_by_app(usess, app);
1047 if (ua_sess == NULL) {
1048 DBG2("UST app pid: %d session id %d not found, creating it",
1049 app->pid, usess->id);
1050 ua_sess = alloc_ust_app_session();
1051 if (ua_sess == NULL) {
1052 /* Only malloc can failed so something is really wrong */
1053 goto end;
1054 }
1055 shadow_copy_session(ua_sess, usess, app);
1056 }
1057
1058 health_code_update(&health_thread_cmd);
1059
1060 if (ua_sess->handle == -1) {
1061 ret = ustctl_create_session(app->sock);
1062 if (ret < 0) {
1063 ERR("Creating session for app pid %d", app->pid);
1064 delete_ust_app_session(-1, ua_sess);
1065 /* This means that the tracer is gone... */
1066 ua_sess = (void*) -1UL;
1067 goto end;
1068 }
1069
1070 ua_sess->handle = ret;
1071
1072 /* Add ust app session to app's HT */
1073 lttng_ht_node_init_ulong(&ua_sess->node, (unsigned long) ua_sess->id);
1074 lttng_ht_add_unique_ulong(app->sessions, &ua_sess->node);
1075
1076 DBG2("UST app session created successfully with handle %d", ret);
1077 }
1078
1079 end:
1080 health_code_update(&health_thread_cmd);
1081 return ua_sess;
1082 }
1083
1084 /*
1085 * Create a context for the channel on the tracer.
1086 */
1087 static
1088 int create_ust_app_channel_context(struct ust_app_session *ua_sess,
1089 struct ust_app_channel *ua_chan, struct lttng_ust_context *uctx,
1090 struct ust_app *app)
1091 {
1092 int ret = 0;
1093 struct lttng_ht_iter iter;
1094 struct lttng_ht_node_ulong *node;
1095 struct ust_app_ctx *ua_ctx;
1096
1097 DBG2("UST app adding context to channel %s", ua_chan->name);
1098
1099 lttng_ht_lookup(ua_chan->ctx, (void *)((unsigned long)uctx->ctx), &iter);
1100 node = lttng_ht_iter_get_node_ulong(&iter);
1101 if (node != NULL) {
1102 ret = -EEXIST;
1103 goto error;
1104 }
1105
1106 ua_ctx = alloc_ust_app_ctx(uctx);
1107 if (ua_ctx == NULL) {
1108 /* malloc failed */
1109 ret = -1;
1110 goto error;
1111 }
1112
1113 lttng_ht_node_init_ulong(&ua_ctx->node, (unsigned long) ua_ctx->ctx.ctx);
1114 lttng_ht_add_unique_ulong(ua_chan->ctx, &ua_ctx->node);
1115
1116 ret = create_ust_channel_context(ua_chan, ua_ctx, app);
1117 if (ret < 0) {
1118 goto error;
1119 }
1120
1121 error:
1122 return ret;
1123 }
1124
1125 /*
1126 * Enable on the tracer side a ust app event for the session and channel.
1127 */
1128 static
1129 int enable_ust_app_event(struct ust_app_session *ua_sess,
1130 struct ust_app_event *ua_event, struct ust_app *app)
1131 {
1132 int ret;
1133
1134 ret = enable_ust_event(app, ua_sess, ua_event);
1135 if (ret < 0) {
1136 goto error;
1137 }
1138
1139 ua_event->enabled = 1;
1140
1141 error:
1142 return ret;
1143 }
1144
1145 /*
1146 * Disable on the tracer side a ust app event for the session and channel.
1147 */
1148 static int disable_ust_app_event(struct ust_app_session *ua_sess,
1149 struct ust_app_event *ua_event, struct ust_app *app)
1150 {
1151 int ret;
1152
1153 ret = disable_ust_event(app, ua_sess, ua_event);
1154 if (ret < 0) {
1155 goto error;
1156 }
1157
1158 ua_event->enabled = 0;
1159
1160 error:
1161 return ret;
1162 }
1163
1164 /*
1165 * Lookup ust app channel for session and disable it on the tracer side.
1166 */
1167 static
1168 int disable_ust_app_channel(struct ust_app_session *ua_sess,
1169 struct ust_app_channel *ua_chan, struct ust_app *app)
1170 {
1171 int ret;
1172
1173 ret = disable_ust_channel(app, ua_sess, ua_chan);
1174 if (ret < 0) {
1175 goto error;
1176 }
1177
1178 ua_chan->enabled = 0;
1179
1180 error:
1181 return ret;
1182 }
1183
1184 /*
1185 * Lookup ust app channel for session and enable it on the tracer side.
1186 */
1187 static int enable_ust_app_channel(struct ust_app_session *ua_sess,
1188 struct ltt_ust_channel *uchan, struct ust_app *app)
1189 {
1190 int ret = 0;
1191 struct lttng_ht_iter iter;
1192 struct lttng_ht_node_str *ua_chan_node;
1193 struct ust_app_channel *ua_chan;
1194
1195 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
1196 ua_chan_node = lttng_ht_iter_get_node_str(&iter);
1197 if (ua_chan_node == NULL) {
1198 DBG2("Unable to find channel %s in ust session id %u",
1199 uchan->name, ua_sess->id);
1200 goto error;
1201 }
1202
1203 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
1204
1205 ret = enable_ust_channel(app, ua_sess, ua_chan);
1206 if (ret < 0) {
1207 goto error;
1208 }
1209
1210 error:
1211 return ret;
1212 }
1213
1214 /*
1215 * Create UST app channel and create it on the tracer. Set ua_chanp of the
1216 * newly created channel if not NULL.
1217 */
1218 static int create_ust_app_channel(struct ust_app_session *ua_sess,
1219 struct ltt_ust_channel *uchan, struct ust_app *app,
1220 struct ust_app_channel **ua_chanp)
1221 {
1222 int ret = 0;
1223 struct lttng_ht_iter iter;
1224 struct lttng_ht_node_str *ua_chan_node;
1225 struct ust_app_channel *ua_chan;
1226
1227 /* Lookup channel in the ust app session */
1228 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
1229 ua_chan_node = lttng_ht_iter_get_node_str(&iter);
1230 if (ua_chan_node != NULL) {
1231 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
1232 goto end;
1233 }
1234
1235 ua_chan = alloc_ust_app_channel(uchan->name, &uchan->attr);
1236 if (ua_chan == NULL) {
1237 /* Only malloc can fail here */
1238 ret = -ENOMEM;
1239 goto error;
1240 }
1241 shadow_copy_channel(ua_chan, uchan);
1242
1243 ret = create_ust_channel(app, ua_sess, ua_chan);
1244 if (ret < 0) {
1245 /* Not found previously means that it does not exist on the tracer */
1246 assert(ret != -LTTNG_UST_ERR_EXIST);
1247 goto error;
1248 }
1249
1250 /* Only add the channel if successful on the tracer side. */
1251 lttng_ht_add_unique_str(ua_sess->channels, &ua_chan->node);
1252
1253 DBG2("UST app create channel %s for PID %d completed", ua_chan->name,
1254 app->pid);
1255
1256 end:
1257 if (ua_chanp) {
1258 *ua_chanp = ua_chan;
1259 }
1260
1261 /* Everything went well. */
1262 return 0;
1263
1264 error:
1265 delete_ust_app_channel(-1, ua_chan);
1266 return ret;
1267 }
1268
1269 /*
1270 * Create UST app event and create it on the tracer side.
1271 */
1272 static
1273 int create_ust_app_event(struct ust_app_session *ua_sess,
1274 struct ust_app_channel *ua_chan, struct ltt_ust_event *uevent,
1275 struct ust_app *app)
1276 {
1277 int ret = 0;
1278 struct ust_app_event *ua_event;
1279
1280 /* Get event node */
1281 ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name,
1282 uevent->filter, uevent->attr.loglevel);
1283 if (ua_event != NULL) {
1284 ret = -EEXIST;
1285 goto end;
1286 }
1287
1288 /* Does not exist so create one */
1289 ua_event = alloc_ust_app_event(uevent->attr.name, &uevent->attr);
1290 if (ua_event == NULL) {
1291 /* Only malloc can failed so something is really wrong */
1292 ret = -ENOMEM;
1293 goto end;
1294 }
1295 shadow_copy_event(ua_event, uevent);
1296
1297 /* Create it on the tracer side */
1298 ret = create_ust_event(app, ua_sess, ua_chan, ua_event);
1299 if (ret < 0) {
1300 /* Not found previously means that it does not exist on the tracer */
1301 assert(ret != -LTTNG_UST_ERR_EXIST);
1302 goto error;
1303 }
1304
1305 add_unique_ust_app_event(ua_chan->events, ua_event);
1306
1307 DBG2("UST app create event %s for PID %d completed", ua_event->name,
1308 app->pid);
1309
1310 end:
1311 return ret;
1312
1313 error:
1314 /* Valid. Calling here is already in a read side lock */
1315 delete_ust_app_event(-1, ua_event);
1316 return ret;
1317 }
1318
1319 /*
1320 * Create UST metadata and open it on the tracer side.
1321 */
1322 static int create_ust_app_metadata(struct ust_app_session *ua_sess,
1323 char *pathname, struct ust_app *app)
1324 {
1325 int ret = 0;
1326
1327 if (ua_sess->metadata == NULL) {
1328 /* Allocate UST metadata */
1329 ua_sess->metadata = trace_ust_create_metadata(pathname);
1330 if (ua_sess->metadata == NULL) {
1331 /* malloc() failed */
1332 goto error;
1333 }
1334
1335 ret = open_ust_metadata(app, ua_sess);
1336 if (ret < 0) {
1337 DBG3("Opening metadata failed. Cleaning up memory");
1338
1339 /* Cleanup failed metadata struct */
1340 free(ua_sess->metadata);
1341 /*
1342 * This is very important because delete_ust_app_session check if
1343 * the pointer is null or not in order to delete the metadata.
1344 */
1345 ua_sess->metadata = NULL;
1346 goto error;
1347 }
1348
1349 DBG2("UST metadata opened for app pid %d", app->pid);
1350 }
1351
1352 /* Open UST metadata stream */
1353 if (ua_sess->metadata->stream_obj == NULL) {
1354 ret = create_ust_stream(app, ua_sess);
1355 if (ret < 0) {
1356 goto error;
1357 }
1358
1359 ret = snprintf(ua_sess->metadata->pathname, PATH_MAX,
1360 "%s/metadata", ua_sess->path);
1361 if (ret < 0) {
1362 PERROR("asprintf UST create stream");
1363 goto error;
1364 }
1365
1366 DBG2("UST metadata stream object created for app pid %d",
1367 app->pid);
1368 } else {
1369 ERR("Attempting to create stream without metadata opened");
1370 goto error;
1371 }
1372
1373 return 0;
1374
1375 error:
1376 return -1;
1377 }
1378
1379 /*
1380 * Return pointer to traceable apps list.
1381 */
1382 struct lttng_ht *ust_app_get_ht(void)
1383 {
1384 return ust_app_ht;
1385 }
1386
1387 /*
1388 * Return ust app pointer or NULL if not found.
1389 */
1390 struct ust_app *ust_app_find_by_pid(pid_t pid)
1391 {
1392 struct lttng_ht_node_ulong *node;
1393 struct lttng_ht_iter iter;
1394
1395 rcu_read_lock();
1396 lttng_ht_lookup(ust_app_ht, (void *)((unsigned long) pid), &iter);
1397 node = lttng_ht_iter_get_node_ulong(&iter);
1398 if (node == NULL) {
1399 DBG2("UST app no found with pid %d", pid);
1400 goto error;
1401 }
1402 rcu_read_unlock();
1403
1404 DBG2("Found UST app by pid %d", pid);
1405
1406 return caa_container_of(node, struct ust_app, pid_n);
1407
1408 error:
1409 rcu_read_unlock();
1410 return NULL;
1411 }
1412
1413 /*
1414 * Using pid and uid (of the app), allocate a new ust_app struct and
1415 * add it to the global traceable app list.
1416 *
1417 * On success, return 0, else return malloc -ENOMEM, or -EINVAL if app
1418 * bitness is not supported.
1419 */
1420 int ust_app_register(struct ust_register_msg *msg, int sock)
1421 {
1422 struct ust_app *lta;
1423 int ret;
1424
1425 if ((msg->bits_per_long == 64 &&
1426 (uatomic_read(&ust_consumerd64_fd) == -EINVAL))
1427 || (msg->bits_per_long == 32 &&
1428 (uatomic_read(&ust_consumerd32_fd) == -EINVAL))) {
1429 ERR("Registration failed: application \"%s\" (pid: %d) has "
1430 "%d-bit long, but no consumerd for this long size is available.\n",
1431 msg->name, msg->pid, msg->bits_per_long);
1432 ret = close(sock);
1433 if (ret) {
1434 PERROR("close");
1435 }
1436 lttng_fd_put(LTTNG_FD_APPS, 1);
1437 return -EINVAL;
1438 }
1439 if (msg->major != LTTNG_UST_COMM_MAJOR) {
1440 ERR("Registration failed: application \"%s\" (pid: %d) has "
1441 "communication protocol version %u.%u, but sessiond supports 2.x.\n",
1442 msg->name, msg->pid, msg->major, msg->minor);
1443 ret = close(sock);
1444 if (ret) {
1445 PERROR("close");
1446 }
1447 lttng_fd_put(LTTNG_FD_APPS, 1);
1448 return -EINVAL;
1449 }
1450 lta = zmalloc(sizeof(struct ust_app));
1451 if (lta == NULL) {
1452 PERROR("malloc");
1453 return -ENOMEM;
1454 }
1455
1456 lta->ppid = msg->ppid;
1457 lta->uid = msg->uid;
1458 lta->gid = msg->gid;
1459 lta->compatible = 0; /* Not compatible until proven */
1460 lta->bits_per_long = msg->bits_per_long;
1461 lta->v_major = msg->major;
1462 lta->v_minor = msg->minor;
1463 strncpy(lta->name, msg->name, sizeof(lta->name));
1464 lta->name[16] = '\0';
1465 lta->sessions = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
1466
1467 lta->pid = msg->pid;
1468 lttng_ht_node_init_ulong(&lta->pid_n, (unsigned long)lta->pid);
1469 lta->sock = sock;
1470 lttng_ht_node_init_ulong(&lta->sock_n, (unsigned long)lta->sock);
1471
1472 CDS_INIT_LIST_HEAD(&lta->teardown_head);
1473
1474 rcu_read_lock();
1475
1476 /*
1477 * On a re-registration, we want to kick out the previous registration of
1478 * that pid
1479 */
1480 lttng_ht_add_replace_ulong(ust_app_ht, &lta->pid_n);
1481
1482 /*
1483 * The socket _should_ be unique until _we_ call close. So, a add_unique
1484 * for the ust_app_ht_by_sock is used which asserts fail if the entry was
1485 * already in the table.
1486 */
1487 lttng_ht_add_unique_ulong(ust_app_ht_by_sock, &lta->sock_n);
1488
1489 rcu_read_unlock();
1490
1491 DBG("App registered with pid:%d ppid:%d uid:%d gid:%d sock:%d name:%s"
1492 " (version %d.%d)", lta->pid, lta->ppid, lta->uid, lta->gid,
1493 lta->sock, lta->name, lta->v_major, lta->v_minor);
1494
1495 return 0;
1496 }
1497
1498 /*
1499 * Unregister app by removing it from the global traceable app list and freeing
1500 * the data struct.
1501 *
1502 * The socket is already closed at this point so no close to sock.
1503 */
1504 void ust_app_unregister(int sock)
1505 {
1506 struct ust_app *lta;
1507 struct lttng_ht_node_ulong *node;
1508 struct lttng_ht_iter iter;
1509 struct ust_app_session *ua_sess;
1510 int ret;
1511
1512 rcu_read_lock();
1513
1514 /* Get the node reference for a call_rcu */
1515 lttng_ht_lookup(ust_app_ht_by_sock, (void *)((unsigned long) sock), &iter);
1516 node = lttng_ht_iter_get_node_ulong(&iter);
1517 if (node == NULL) {
1518 ERR("Unable to find app by sock %d", sock);
1519 goto error;
1520 }
1521
1522 lta = caa_container_of(node, struct ust_app, sock_n);
1523
1524 DBG("PID %d unregistering with sock %d", lta->pid, sock);
1525
1526 /* Remove application from PID hash table */
1527 ret = lttng_ht_del(ust_app_ht_by_sock, &iter);
1528 assert(!ret);
1529
1530 /* Assign second node for deletion */
1531 iter.iter.node = &lta->pid_n.node;
1532
1533 /*
1534 * Ignore return value since the node might have been removed before by an
1535 * add replace during app registration because the PID can be reassigned by
1536 * the OS.
1537 */
1538 ret = lttng_ht_del(ust_app_ht, &iter);
1539 if (ret) {
1540 DBG3("Unregister app by PID %d failed. This can happen on pid reuse",
1541 lta->pid);
1542 }
1543
1544 /* Remove sessions so they are not visible during deletion.*/
1545 cds_lfht_for_each_entry(lta->sessions->ht, &iter.iter, ua_sess,
1546 node.node) {
1547 ret = lttng_ht_del(lta->sessions, &iter);
1548 if (ret) {
1549 /* The session was already removed so scheduled for teardown. */
1550 continue;
1551 }
1552
1553 /*
1554 * Add session to list for teardown. This is safe since at this point we
1555 * are the only one using this list.
1556 */
1557 cds_list_add(&ua_sess->teardown_node, &lta->teardown_head);
1558 }
1559
1560 /* Free memory */
1561 call_rcu(&lta->pid_n.head, delete_ust_app_rcu);
1562
1563 error:
1564 rcu_read_unlock();
1565 return;
1566 }
1567
1568 /*
1569 * Return traceable_app_count
1570 */
1571 unsigned long ust_app_list_count(void)
1572 {
1573 unsigned long count;
1574
1575 rcu_read_lock();
1576 count = lttng_ht_get_count(ust_app_ht);
1577 rcu_read_unlock();
1578
1579 return count;
1580 }
1581
1582 /*
1583 * Fill events array with all events name of all registered apps.
1584 */
1585 int ust_app_list_events(struct lttng_event **events)
1586 {
1587 int ret, handle;
1588 size_t nbmem, count = 0;
1589 struct lttng_ht_iter iter;
1590 struct ust_app *app;
1591 struct lttng_event *tmp;
1592
1593 nbmem = UST_APP_EVENT_LIST_SIZE;
1594 tmp = zmalloc(nbmem * sizeof(struct lttng_event));
1595 if (tmp == NULL) {
1596 PERROR("zmalloc ust app events");
1597 ret = -ENOMEM;
1598 goto error;
1599 }
1600
1601 rcu_read_lock();
1602
1603 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
1604 struct lttng_ust_tracepoint_iter uiter;
1605
1606 health_code_update(&health_thread_cmd);
1607
1608 if (!app->compatible) {
1609 /*
1610 * TODO: In time, we should notice the caller of this error by
1611 * telling him that this is a version error.
1612 */
1613 continue;
1614 }
1615 handle = ustctl_tracepoint_list(app->sock);
1616 if (handle < 0) {
1617 ERR("UST app list events getting handle failed for app pid %d",
1618 app->pid);
1619 continue;
1620 }
1621
1622 while ((ret = ustctl_tracepoint_list_get(app->sock, handle,
1623 &uiter)) != -LTTNG_UST_ERR_NOENT) {
1624 health_code_update(&health_thread_cmd);
1625 if (count >= nbmem) {
1626 /* In case the realloc fails, we free the memory */
1627 void *tmp_ptr = (void *) tmp;
1628 DBG2("Reallocating event list from %zu to %zu entries", nbmem,
1629 2 * nbmem);
1630 nbmem *= 2;
1631 tmp = realloc(tmp, nbmem * sizeof(struct lttng_event));
1632 if (tmp == NULL) {
1633 PERROR("realloc ust app events");
1634 free(tmp_ptr);
1635 ret = -ENOMEM;
1636 goto rcu_error;
1637 }
1638 }
1639 memcpy(tmp[count].name, uiter.name, LTTNG_UST_SYM_NAME_LEN);
1640 tmp[count].loglevel = uiter.loglevel;
1641 tmp[count].type = (enum lttng_event_type) LTTNG_UST_TRACEPOINT;
1642 tmp[count].pid = app->pid;
1643 tmp[count].enabled = -1;
1644 count++;
1645 }
1646 }
1647
1648 ret = count;
1649 *events = tmp;
1650
1651 DBG2("UST app list events done (%zu events)", count);
1652
1653 rcu_error:
1654 rcu_read_unlock();
1655 error:
1656 health_code_update(&health_thread_cmd);
1657 return ret;
1658 }
1659
1660 /*
1661 * Fill events array with all events name of all registered apps.
1662 */
1663 int ust_app_list_event_fields(struct lttng_event_field **fields)
1664 {
1665 int ret, handle;
1666 size_t nbmem, count = 0;
1667 struct lttng_ht_iter iter;
1668 struct ust_app *app;
1669 struct lttng_event_field *tmp;
1670
1671 nbmem = UST_APP_EVENT_LIST_SIZE;
1672 tmp = zmalloc(nbmem * sizeof(struct lttng_event_field));
1673 if (tmp == NULL) {
1674 PERROR("zmalloc ust app event fields");
1675 ret = -ENOMEM;
1676 goto error;
1677 }
1678
1679 rcu_read_lock();
1680
1681 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
1682 struct lttng_ust_field_iter uiter;
1683
1684 health_code_update(&health_thread_cmd);
1685
1686 if (!app->compatible) {
1687 /*
1688 * TODO: In time, we should notice the caller of this error by
1689 * telling him that this is a version error.
1690 */
1691 continue;
1692 }
1693 handle = ustctl_tracepoint_field_list(app->sock);
1694 if (handle < 0) {
1695 ERR("UST app list event fields getting handle failed for app pid %d",
1696 app->pid);
1697 continue;
1698 }
1699
1700 while ((ret = ustctl_tracepoint_field_list_get(app->sock, handle,
1701 &uiter)) != -LTTNG_UST_ERR_NOENT) {
1702 health_code_update(&health_thread_cmd);
1703 if (count >= nbmem) {
1704 /* In case the realloc fails, we free the memory */
1705 void *tmp_ptr = (void *) tmp;
1706 DBG2("Reallocating event field list from %zu to %zu entries", nbmem,
1707 2 * nbmem);
1708 nbmem *= 2;
1709 tmp = realloc(tmp, nbmem * sizeof(struct lttng_event_field));
1710 if (tmp == NULL) {
1711 PERROR("realloc ust app event fields");
1712 free(tmp_ptr);
1713 ret = -ENOMEM;
1714 goto rcu_error;
1715 }
1716 }
1717
1718 memcpy(tmp[count].field_name, uiter.field_name, LTTNG_UST_SYM_NAME_LEN);
1719 tmp[count].type = uiter.type;
1720 tmp[count].nowrite = uiter.nowrite;
1721
1722 memcpy(tmp[count].event.name, uiter.event_name, LTTNG_UST_SYM_NAME_LEN);
1723 tmp[count].event.loglevel = uiter.loglevel;
1724 tmp[count].event.type = LTTNG_UST_TRACEPOINT;
1725 tmp[count].event.pid = app->pid;
1726 tmp[count].event.enabled = -1;
1727 count++;
1728 }
1729 }
1730
1731 ret = count;
1732 *fields = tmp;
1733
1734 DBG2("UST app list event fields done (%zu events)", count);
1735
1736 rcu_error:
1737 rcu_read_unlock();
1738 error:
1739 health_code_update(&health_thread_cmd);
1740 return ret;
1741 }
1742
1743 /*
1744 * Free and clean all traceable apps of the global list.
1745 */
1746 void ust_app_clean_list(void)
1747 {
1748 int ret;
1749 struct ust_app *app;
1750 struct lttng_ht_iter iter;
1751
1752 DBG2("UST app cleaning registered apps hash table");
1753
1754 rcu_read_lock();
1755
1756 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
1757 ret = lttng_ht_del(ust_app_ht, &iter);
1758 assert(!ret);
1759 call_rcu(&app->pid_n.head, delete_ust_app_rcu);
1760 }
1761
1762 /* Cleanup socket hash table */
1763 cds_lfht_for_each_entry(ust_app_ht_by_sock->ht, &iter.iter, app,
1764 sock_n.node) {
1765 ret = lttng_ht_del(ust_app_ht_by_sock, &iter);
1766 assert(!ret);
1767 }
1768
1769 /* Destroy is done only when the ht is empty */
1770 lttng_ht_destroy(ust_app_ht);
1771 lttng_ht_destroy(ust_app_ht_by_sock);
1772
1773 rcu_read_unlock();
1774 }
1775
1776 /*
1777 * Init UST app hash table.
1778 */
1779 void ust_app_ht_alloc(void)
1780 {
1781 ust_app_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
1782 ust_app_ht_by_sock = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
1783 }
1784
1785 /*
1786 * For a specific UST session, disable the channel for all registered apps.
1787 */
1788 int ust_app_disable_channel_glb(struct ltt_ust_session *usess,
1789 struct ltt_ust_channel *uchan)
1790 {
1791 int ret = 0;
1792 struct lttng_ht_iter iter;
1793 struct lttng_ht_node_str *ua_chan_node;
1794 struct ust_app *app;
1795 struct ust_app_session *ua_sess;
1796 struct ust_app_channel *ua_chan;
1797
1798 if (usess == NULL || uchan == NULL) {
1799 ERR("Disabling UST global channel with NULL values");
1800 ret = -1;
1801 goto error;
1802 }
1803
1804 DBG2("UST app disabling channel %s from global domain for session id %d",
1805 uchan->name, usess->id);
1806
1807 rcu_read_lock();
1808
1809 /* For every registered applications */
1810 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
1811 struct lttng_ht_iter uiter;
1812 if (!app->compatible) {
1813 /*
1814 * TODO: In time, we should notice the caller of this error by
1815 * telling him that this is a version error.
1816 */
1817 continue;
1818 }
1819 ua_sess = lookup_session_by_app(usess, app);
1820 if (ua_sess == NULL) {
1821 continue;
1822 }
1823
1824 /* Get channel */
1825 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
1826 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
1827 /* If the session if found for the app, the channel must be there */
1828 assert(ua_chan_node);
1829
1830 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
1831 /* The channel must not be already disabled */
1832 assert(ua_chan->enabled == 1);
1833
1834 /* Disable channel onto application */
1835 ret = disable_ust_app_channel(ua_sess, ua_chan, app);
1836 if (ret < 0) {
1837 /* XXX: We might want to report this error at some point... */
1838 continue;
1839 }
1840 }
1841
1842 rcu_read_unlock();
1843
1844 error:
1845 return ret;
1846 }
1847
1848 /*
1849 * For a specific UST session, enable the channel for all registered apps.
1850 */
1851 int ust_app_enable_channel_glb(struct ltt_ust_session *usess,
1852 struct ltt_ust_channel *uchan)
1853 {
1854 int ret = 0;
1855 struct lttng_ht_iter iter;
1856 struct ust_app *app;
1857 struct ust_app_session *ua_sess;
1858
1859 if (usess == NULL || uchan == NULL) {
1860 ERR("Adding UST global channel to NULL values");
1861 ret = -1;
1862 goto error;
1863 }
1864
1865 DBG2("UST app enabling channel %s to global domain for session id %d",
1866 uchan->name, usess->id);
1867
1868 rcu_read_lock();
1869
1870 /* For every registered applications */
1871 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
1872 if (!app->compatible) {
1873 /*
1874 * TODO: In time, we should notice the caller of this error by
1875 * telling him that this is a version error.
1876 */
1877 continue;
1878 }
1879 ua_sess = lookup_session_by_app(usess, app);
1880 if (ua_sess == NULL) {
1881 continue;
1882 }
1883
1884 /* Enable channel onto application */
1885 ret = enable_ust_app_channel(ua_sess, uchan, app);
1886 if (ret < 0) {
1887 /* XXX: We might want to report this error at some point... */
1888 continue;
1889 }
1890 }
1891
1892 rcu_read_unlock();
1893
1894 error:
1895 return ret;
1896 }
1897
1898 /*
1899 * Disable an event in a channel and for a specific session.
1900 */
1901 int ust_app_disable_event_glb(struct ltt_ust_session *usess,
1902 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent)
1903 {
1904 int ret = 0;
1905 struct lttng_ht_iter iter, uiter;
1906 struct lttng_ht_node_str *ua_chan_node, *ua_event_node;
1907 struct ust_app *app;
1908 struct ust_app_session *ua_sess;
1909 struct ust_app_channel *ua_chan;
1910 struct ust_app_event *ua_event;
1911
1912 DBG("UST app disabling event %s for all apps in channel "
1913 "%s for session id %d", uevent->attr.name, uchan->name, usess->id);
1914
1915 rcu_read_lock();
1916
1917 /* For all registered applications */
1918 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
1919 if (!app->compatible) {
1920 /*
1921 * TODO: In time, we should notice the caller of this error by
1922 * telling him that this is a version error.
1923 */
1924 continue;
1925 }
1926 ua_sess = lookup_session_by_app(usess, app);
1927 if (ua_sess == NULL) {
1928 /* Next app */
1929 continue;
1930 }
1931
1932 /* Lookup channel in the ust app session */
1933 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
1934 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
1935 if (ua_chan_node == NULL) {
1936 DBG2("Channel %s not found in session id %d for app pid %d."
1937 "Skipping", uchan->name, usess->id, app->pid);
1938 continue;
1939 }
1940 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
1941
1942 lttng_ht_lookup(ua_chan->events, (void *)uevent->attr.name, &uiter);
1943 ua_event_node = lttng_ht_iter_get_node_str(&uiter);
1944 if (ua_event_node == NULL) {
1945 DBG2("Event %s not found in channel %s for app pid %d."
1946 "Skipping", uevent->attr.name, uchan->name, app->pid);
1947 continue;
1948 }
1949 ua_event = caa_container_of(ua_event_node, struct ust_app_event, node);
1950
1951 ret = disable_ust_app_event(ua_sess, ua_event, app);
1952 if (ret < 0) {
1953 /* XXX: Report error someday... */
1954 continue;
1955 }
1956 }
1957
1958 rcu_read_unlock();
1959
1960 return ret;
1961 }
1962
1963 /*
1964 * For a specific UST session and UST channel, the event for all
1965 * registered apps.
1966 */
1967 int ust_app_disable_all_event_glb(struct ltt_ust_session *usess,
1968 struct ltt_ust_channel *uchan)
1969 {
1970 int ret = 0;
1971 struct lttng_ht_iter iter, uiter;
1972 struct lttng_ht_node_str *ua_chan_node;
1973 struct ust_app *app;
1974 struct ust_app_session *ua_sess;
1975 struct ust_app_channel *ua_chan;
1976 struct ust_app_event *ua_event;
1977
1978 DBG("UST app disabling all event for all apps in channel "
1979 "%s for session id %d", uchan->name, usess->id);
1980
1981 rcu_read_lock();
1982
1983 /* For all registered applications */
1984 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
1985 if (!app->compatible) {
1986 /*
1987 * TODO: In time, we should notice the caller of this error by
1988 * telling him that this is a version error.
1989 */
1990 continue;
1991 }
1992 ua_sess = lookup_session_by_app(usess, app);
1993 if (!ua_sess) {
1994 /* The application has problem or is probably dead. */
1995 continue;
1996 }
1997
1998 /* Lookup channel in the ust app session */
1999 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
2000 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
2001 /* If the channel is not found, there is a code flow error */
2002 assert(ua_chan_node);
2003
2004 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
2005
2006 /* Disable each events of channel */
2007 cds_lfht_for_each_entry(ua_chan->events->ht, &uiter.iter, ua_event,
2008 node.node) {
2009 ret = disable_ust_app_event(ua_sess, ua_event, app);
2010 if (ret < 0) {
2011 /* XXX: Report error someday... */
2012 continue;
2013 }
2014 }
2015 }
2016
2017 rcu_read_unlock();
2018
2019 return ret;
2020 }
2021
2022 /*
2023 * For a specific UST session, create the channel for all registered apps.
2024 */
2025 int ust_app_create_channel_glb(struct ltt_ust_session *usess,
2026 struct ltt_ust_channel *uchan)
2027 {
2028 int ret = 0;
2029 struct lttng_ht_iter iter;
2030 struct ust_app *app;
2031 struct ust_app_session *ua_sess;
2032
2033 /* Very wrong code flow */
2034 assert(usess);
2035 assert(uchan);
2036
2037 DBG2("UST app adding channel %s to global domain for session id %d",
2038 uchan->name, usess->id);
2039
2040 rcu_read_lock();
2041
2042 /* For every registered applications */
2043 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
2044 if (!app->compatible) {
2045 /*
2046 * TODO: In time, we should notice the caller of this error by
2047 * telling him that this is a version error.
2048 */
2049 continue;
2050 }
2051 /*
2052 * Create session on the tracer side and add it to app session HT. Note
2053 * that if session exist, it will simply return a pointer to the ust
2054 * app session.
2055 */
2056 ua_sess = create_ust_app_session(usess, app);
2057 if (ua_sess == NULL) {
2058 /* The malloc() failed. */
2059 ret = -ENOMEM;
2060 goto error_rcu_unlock;
2061 } else if (ua_sess == (void *) -1UL) {
2062 /*
2063 * The application's socket is not valid. Either a bad socket or a
2064 * timeout on it. We can't inform yet the caller that for a
2065 * specific app, the session failed so we continue here.
2066 */
2067 continue;
2068 }
2069
2070 /* Create channel onto application. We don't need the chan ref. */
2071 ret = create_ust_app_channel(ua_sess, uchan, app, NULL);
2072 if (ret < 0 && ret == -ENOMEM) {
2073 /* No more memory is a fatal error. Stop right now. */
2074 goto error_rcu_unlock;
2075 }
2076 }
2077
2078 error_rcu_unlock:
2079 rcu_read_unlock();
2080 return ret;
2081 }
2082
2083 /*
2084 * Enable event for a specific session and channel on the tracer.
2085 */
2086 int ust_app_enable_event_glb(struct ltt_ust_session *usess,
2087 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent)
2088 {
2089 int ret = 0;
2090 struct lttng_ht_iter iter, uiter;
2091 struct lttng_ht_node_str *ua_chan_node;
2092 struct ust_app *app;
2093 struct ust_app_session *ua_sess;
2094 struct ust_app_channel *ua_chan;
2095 struct ust_app_event *ua_event;
2096
2097 DBG("UST app enabling event %s for all apps for session id %d",
2098 uevent->attr.name, usess->id);
2099
2100 /*
2101 * NOTE: At this point, this function is called only if the session and
2102 * channel passed are already created for all apps. and enabled on the
2103 * tracer also.
2104 */
2105
2106 rcu_read_lock();
2107
2108 /* For all registered applications */
2109 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
2110 if (!app->compatible) {
2111 /*
2112 * TODO: In time, we should notice the caller of this error by
2113 * telling him that this is a version error.
2114 */
2115 continue;
2116 }
2117 ua_sess = lookup_session_by_app(usess, app);
2118 if (!ua_sess) {
2119 /* The application has problem or is probably dead. */
2120 continue;
2121 }
2122
2123 /* Lookup channel in the ust app session */
2124 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
2125 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
2126 /* If the channel is not found, there is a code flow error */
2127 assert(ua_chan_node);
2128
2129 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
2130
2131 /* Get event node */
2132 ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name,
2133 uevent->filter, uevent->attr.loglevel);
2134 if (ua_event == NULL) {
2135 DBG3("UST app enable event %s not found for app PID %d."
2136 "Skipping app", uevent->attr.name, app->pid);
2137 continue;
2138 }
2139
2140 ret = enable_ust_app_event(ua_sess, ua_event, app);
2141 if (ret < 0) {
2142 goto error;
2143 }
2144 }
2145
2146 error:
2147 rcu_read_unlock();
2148 return ret;
2149 }
2150
2151 /*
2152 * For a specific existing UST session and UST channel, creates the event for
2153 * all registered apps.
2154 */
2155 int ust_app_create_event_glb(struct ltt_ust_session *usess,
2156 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent)
2157 {
2158 int ret = 0;
2159 struct lttng_ht_iter iter, uiter;
2160 struct lttng_ht_node_str *ua_chan_node;
2161 struct ust_app *app;
2162 struct ust_app_session *ua_sess;
2163 struct ust_app_channel *ua_chan;
2164
2165 DBG("UST app creating event %s for all apps for session id %d",
2166 uevent->attr.name, usess->id);
2167
2168 rcu_read_lock();
2169
2170 /* For all registered applications */
2171 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
2172 if (!app->compatible) {
2173 /*
2174 * TODO: In time, we should notice the caller of this error by
2175 * telling him that this is a version error.
2176 */
2177 continue;
2178 }
2179 ua_sess = lookup_session_by_app(usess, app);
2180 if (!ua_sess) {
2181 /* The application has problem or is probably dead. */
2182 continue;
2183 }
2184
2185 /* Lookup channel in the ust app session */
2186 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
2187 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
2188 /* If the channel is not found, there is a code flow error */
2189 assert(ua_chan_node);
2190
2191 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
2192
2193 ret = create_ust_app_event(ua_sess, ua_chan, uevent, app);
2194 if (ret < 0) {
2195 if (ret != -LTTNG_UST_ERR_EXIST) {
2196 /* Possible value at this point: -ENOMEM. If so, we stop! */
2197 break;
2198 }
2199 DBG2("UST app event %s already exist on app PID %d",
2200 uevent->attr.name, app->pid);
2201 continue;
2202 }
2203 }
2204
2205 rcu_read_unlock();
2206
2207 return ret;
2208 }
2209
2210 /*
2211 * Start tracing for a specific UST session and app.
2212 */
2213 int ust_app_start_trace(struct ltt_ust_session *usess, struct ust_app *app)
2214 {
2215 int ret = 0;
2216 struct lttng_ht_iter iter;
2217 struct ust_app_session *ua_sess;
2218 struct ust_app_channel *ua_chan;
2219 struct ltt_ust_stream *ustream;
2220 struct consumer_socket *socket;
2221
2222 DBG("Starting tracing for ust app pid %d", app->pid);
2223
2224 rcu_read_lock();
2225
2226 if (!app->compatible) {
2227 goto end;
2228 }
2229
2230 ua_sess = lookup_session_by_app(usess, app);
2231 if (ua_sess == NULL) {
2232 /* The session is in teardown process. Ignore and continue. */
2233 goto end;
2234 }
2235
2236 /* Upon restart, we skip the setup, already done */
2237 if (ua_sess->started) {
2238 goto skip_setup;
2239 }
2240
2241 /* Create directories if consumer is LOCAL and has a path defined. */
2242 if (usess->consumer->type == CONSUMER_DST_LOCAL &&
2243 strlen(usess->consumer->dst.trace_path) > 0) {
2244 ret = run_as_mkdir_recursive(usess->consumer->dst.trace_path,
2245 S_IRWXU | S_IRWXG, usess->uid, usess->gid);
2246 if (ret < 0) {
2247 if (ret != -EEXIST) {
2248 ERR("Trace directory creation error");
2249 ret = -1;
2250 goto error_rcu_unlock;
2251 }
2252 }
2253 }
2254
2255 ret = create_ust_app_metadata(ua_sess, usess->pathname, app);
2256 if (ret < 0) {
2257 ret = LTTNG_ERR_UST_META_FAIL;
2258 goto error_rcu_unlock;
2259 }
2260
2261 /* For each channel */
2262 cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
2263 node.node) {
2264 /* Create all streams */
2265 while (1) {
2266 /* Create UST stream */
2267 ustream = zmalloc(sizeof(*ustream));
2268 if (ustream == NULL) {
2269 PERROR("zmalloc ust stream");
2270 goto error_rcu_unlock;
2271 }
2272
2273 /* We are going to receive 2 fds, we need to reserve them. */
2274 ret = lttng_fd_get(LTTNG_FD_APPS, 2);
2275 if (ret < 0) {
2276 ERR("Exhausted number of available FD upon stream create");
2277 free(ustream);
2278 goto error_rcu_unlock;
2279 }
2280
2281 health_code_update(&health_thread_cmd);
2282
2283 ret = ustctl_create_stream(app->sock, ua_chan->obj,
2284 &ustream->obj);
2285 if (ret < 0) {
2286 /* Got all streams */
2287 lttng_fd_put(LTTNG_FD_APPS, 2);
2288 free(ustream);
2289 ret = LTTNG_ERR_UST_STREAM_FAIL;
2290 break;
2291 }
2292 ustream->handle = ustream->obj->handle;
2293
2294 health_code_update(&health_thread_cmd);
2295
2296 /* Order is important */
2297 cds_list_add_tail(&ustream->list, &ua_chan->streams.head);
2298 ret = snprintf(ustream->name, sizeof(ustream->name), "%s_%u",
2299 ua_chan->name, ua_chan->streams.count);
2300 ua_chan->streams.count++;
2301 if (ret < 0) {
2302 PERROR("asprintf UST create stream");
2303 /*
2304 * XXX what should we do here with the
2305 * stream ?
2306 */
2307 continue;
2308 }
2309 DBG2("UST stream %d ready (handle: %d)", ua_chan->streams.count,
2310 ustream->handle);
2311 }
2312
2313 health_code_update(&health_thread_cmd);
2314 }
2315
2316 switch (app->bits_per_long) {
2317 case 64:
2318 socket = consumer_find_socket(uatomic_read(&ust_consumerd64_fd),
2319 usess->consumer);
2320 if (socket == NULL) {
2321 goto skip_setup;
2322 }
2323 break;
2324 case 32:
2325 socket = consumer_find_socket(uatomic_read(&ust_consumerd32_fd),
2326 usess->consumer);
2327 if (socket == NULL) {
2328 goto skip_setup;
2329 }
2330 break;
2331 default:
2332 ret = -EINVAL;
2333 goto error_rcu_unlock;
2334 }
2335
2336 /* Setup UST consumer socket and send fds to it */
2337 ret = ust_consumer_send_session(ua_sess, usess->consumer, socket);
2338 if (ret < 0) {
2339 goto error_rcu_unlock;
2340 }
2341
2342 health_code_update(&health_thread_cmd);
2343
2344 skip_setup:
2345 /* This start the UST tracing */
2346 ret = ustctl_start_session(app->sock, ua_sess->handle);
2347 if (ret < 0) {
2348 ERR("Error starting tracing for app pid: %d", app->pid);
2349 goto error_rcu_unlock;
2350 }
2351
2352 /* Indicate that the session has been started once */
2353 ua_sess->started = 1;
2354
2355 health_code_update(&health_thread_cmd);
2356
2357 /* Quiescent wait after starting trace */
2358 ustctl_wait_quiescent(app->sock);
2359
2360 end:
2361 rcu_read_unlock();
2362 health_code_update(&health_thread_cmd);
2363 return 0;
2364
2365 error_rcu_unlock:
2366 rcu_read_unlock();
2367 health_code_update(&health_thread_cmd);
2368 return -1;
2369 }
2370
2371 /*
2372 * Stop tracing for a specific UST session and app.
2373 */
2374 int ust_app_stop_trace(struct ltt_ust_session *usess, struct ust_app *app)
2375 {
2376 int ret = 0;
2377 struct lttng_ht_iter iter;
2378 struct ust_app_session *ua_sess;
2379 struct ust_app_channel *ua_chan;
2380
2381 DBG("Stopping tracing for ust app pid %d", app->pid);
2382
2383 rcu_read_lock();
2384
2385 if (!app->compatible) {
2386 goto end;
2387 }
2388
2389 ua_sess = lookup_session_by_app(usess, app);
2390 if (ua_sess == NULL) {
2391 goto end;
2392 }
2393
2394 /*
2395 * If started = 0, it means that stop trace has been called for a session
2396 * that was never started. It's possible since we can have a fail start
2397 * from either the application manager thread or the command thread. Simply
2398 * indicate that this is a stop error.
2399 */
2400 if (ua_sess->started == 1) {
2401 goto error_rcu_unlock;
2402 }
2403
2404 health_code_update(&health_thread_cmd);
2405
2406 /* This inhibits UST tracing */
2407 ret = ustctl_stop_session(app->sock, ua_sess->handle);
2408 if (ret < 0) {
2409 ERR("Error stopping tracing for app pid: %d", app->pid);
2410 goto error_rcu_unlock;
2411 }
2412
2413 health_code_update(&health_thread_cmd);
2414
2415 /* Quiescent wait after stopping trace */
2416 ustctl_wait_quiescent(app->sock);
2417
2418 health_code_update(&health_thread_cmd);
2419
2420 /* Flushing buffers */
2421 cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
2422 node.node) {
2423 health_code_update(&health_thread_cmd);
2424 ret = ustctl_sock_flush_buffer(app->sock, ua_chan->obj);
2425 if (ret < 0) {
2426 ERR("UST app PID %d channel %s flush failed with ret %d",
2427 app->pid, ua_chan->name, ret);
2428 /* Continuing flushing all buffers */
2429 continue;
2430 }
2431 }
2432
2433 health_code_update(&health_thread_cmd);
2434
2435 /* Flush all buffers before stopping */
2436 ret = ustctl_sock_flush_buffer(app->sock, ua_sess->metadata->obj);
2437 if (ret < 0) {
2438 ERR("UST app PID %d metadata flush failed with ret %d", app->pid,
2439 ret);
2440 }
2441
2442 end:
2443 rcu_read_unlock();
2444 health_code_update(&health_thread_cmd);
2445 return 0;
2446
2447 error_rcu_unlock:
2448 rcu_read_unlock();
2449 health_code_update(&health_thread_cmd);
2450 return -1;
2451 }
2452
2453 /*
2454 * Destroy a specific UST session in apps.
2455 */
2456 static int destroy_trace(struct ltt_ust_session *usess, struct ust_app *app)
2457 {
2458 struct ust_app_session *ua_sess;
2459 struct lttng_ust_object_data obj;
2460 struct lttng_ht_iter iter;
2461 struct lttng_ht_node_ulong *node;
2462 int ret;
2463
2464 DBG("Destroy tracing for ust app pid %d", app->pid);
2465
2466 rcu_read_lock();
2467
2468 if (!app->compatible) {
2469 goto end;
2470 }
2471
2472 __lookup_session_by_app(usess, app, &iter);
2473 node = lttng_ht_iter_get_node_ulong(&iter);
2474 if (node == NULL) {
2475 /* Session is being or is deleted. */
2476 goto end;
2477 }
2478 ua_sess = caa_container_of(node, struct ust_app_session, node);
2479 ret = lttng_ht_del(app->sessions, &iter);
2480 if (ret) {
2481 /* Already scheduled for teardown. */
2482 goto end;
2483 }
2484
2485 obj.handle = ua_sess->handle;
2486 obj.shm_fd = -1;
2487 obj.wait_fd = -1;
2488 obj.memory_map_size = 0;
2489 health_code_update(&health_thread_cmd);
2490 ustctl_release_object(app->sock, &obj);
2491
2492 health_code_update(&health_thread_cmd);
2493 delete_ust_app_session(app->sock, ua_sess);
2494
2495 /* Quiescent wait after stopping trace */
2496 ustctl_wait_quiescent(app->sock);
2497
2498 end:
2499 rcu_read_unlock();
2500 health_code_update(&health_thread_cmd);
2501 return 0;
2502 }
2503
2504 /*
2505 * Start tracing for the UST session.
2506 */
2507 int ust_app_start_trace_all(struct ltt_ust_session *usess)
2508 {
2509 int ret = 0;
2510 struct lttng_ht_iter iter;
2511 struct ust_app *app;
2512
2513 DBG("Starting all UST traces");
2514
2515 rcu_read_lock();
2516
2517 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
2518 ret = ust_app_start_trace(usess, app);
2519 if (ret < 0) {
2520 /* Continue to next apps even on error */
2521 continue;
2522 }
2523 }
2524
2525 rcu_read_unlock();
2526
2527 return 0;
2528 }
2529
2530 /*
2531 * Start tracing for the UST session.
2532 */
2533 int ust_app_stop_trace_all(struct ltt_ust_session *usess)
2534 {
2535 int ret = 0;
2536 struct lttng_ht_iter iter;
2537 struct ust_app *app;
2538
2539 DBG("Stopping all UST traces");
2540
2541 rcu_read_lock();
2542
2543 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
2544 ret = ust_app_stop_trace(usess, app);
2545 if (ret < 0) {
2546 /* Continue to next apps even on error */
2547 continue;
2548 }
2549 }
2550
2551 rcu_read_unlock();
2552
2553 return 0;
2554 }
2555
2556 /*
2557 * Destroy app UST session.
2558 */
2559 int ust_app_destroy_trace_all(struct ltt_ust_session *usess)
2560 {
2561 int ret = 0;
2562 struct lttng_ht_iter iter;
2563 struct ust_app *app;
2564
2565 DBG("Destroy all UST traces");
2566
2567 rcu_read_lock();
2568
2569 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
2570 ret = destroy_trace(usess, app);
2571 if (ret < 0) {
2572 /* Continue to next apps even on error */
2573 continue;
2574 }
2575 }
2576
2577 rcu_read_unlock();
2578
2579 return 0;
2580 }
2581
2582 /*
2583 * Add channels/events from UST global domain to registered apps at sock.
2584 */
2585 void ust_app_global_update(struct ltt_ust_session *usess, int sock)
2586 {
2587 int ret = 0;
2588 struct lttng_ht_iter iter, uiter, iter_ctx;
2589 struct ust_app *app;
2590 struct ust_app_session *ua_sess;
2591 struct ust_app_channel *ua_chan;
2592 struct ust_app_event *ua_event;
2593 struct ust_app_ctx *ua_ctx;
2594
2595 assert(usess);
2596
2597 DBG2("UST app global update for app sock %d for session id %d", sock,
2598 usess->id);
2599
2600 rcu_read_lock();
2601
2602 app = find_app_by_sock(sock);
2603 if (app == NULL) {
2604 ERR("Failed to update app sock %d", sock);
2605 goto error;
2606 }
2607
2608 if (!app->compatible) {
2609 goto error;
2610 }
2611
2612 ua_sess = create_ust_app_session(usess, app);
2613 if (ua_sess == NULL || ua_sess == (void *) -1UL) {
2614 /* Tracer is gone for this session and has been freed */
2615 goto error;
2616 }
2617
2618 /*
2619 * We can iterate safely here over all UST app session sicne the create ust
2620 * app session above made a shadow copy of the UST global domain from the
2621 * ltt ust session.
2622 */
2623 cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
2624 node.node) {
2625 ret = create_ust_channel(app, ua_sess, ua_chan);
2626 if (ret < 0) {
2627 /* FIXME: Should we quit here or continue... */
2628 continue;
2629 }
2630
2631 cds_lfht_for_each_entry(ua_chan->ctx->ht, &iter_ctx.iter, ua_ctx,
2632 node.node) {
2633 ret = create_ust_channel_context(ua_chan, ua_ctx, app);
2634 if (ret < 0) {
2635 /* FIXME: Should we quit here or continue... */
2636 continue;
2637 }
2638 }
2639
2640
2641 /* For each events */
2642 cds_lfht_for_each_entry(ua_chan->events->ht, &uiter.iter, ua_event,
2643 node.node) {
2644 ret = create_ust_event(app, ua_sess, ua_chan, ua_event);
2645 if (ret < 0) {
2646 /* FIXME: Should we quit here or continue... */
2647 continue;
2648 }
2649
2650 ret = set_ust_event_filter(ua_event, app);
2651 if (ret < 0) {
2652 /* FIXME: Should we quit here or continue... */
2653 continue;
2654 }
2655 }
2656 }
2657
2658 if (usess->start_trace) {
2659 ret = ust_app_start_trace(usess, app);
2660 if (ret < 0) {
2661 goto error;
2662 }
2663
2664 DBG2("UST trace started for app pid %d", app->pid);
2665 }
2666
2667 error:
2668 rcu_read_unlock();
2669 return;
2670 }
2671
2672 /*
2673 * Add context to a specific channel for global UST domain.
2674 */
2675 int ust_app_add_ctx_channel_glb(struct ltt_ust_session *usess,
2676 struct ltt_ust_channel *uchan, struct ltt_ust_context *uctx)
2677 {
2678 int ret = 0;
2679 struct lttng_ht_node_str *ua_chan_node;
2680 struct lttng_ht_iter iter, uiter;
2681 struct ust_app_channel *ua_chan = NULL;
2682 struct ust_app_session *ua_sess;
2683 struct ust_app *app;
2684
2685 rcu_read_lock();
2686
2687 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
2688 if (!app->compatible) {
2689 /*
2690 * TODO: In time, we should notice the caller of this error by
2691 * telling him that this is a version error.
2692 */
2693 continue;
2694 }
2695 ua_sess = lookup_session_by_app(usess, app);
2696 if (ua_sess == NULL) {
2697 continue;
2698 }
2699
2700 /* Lookup channel in the ust app session */
2701 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
2702 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
2703 if (ua_chan_node == NULL) {
2704 continue;
2705 }
2706 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel,
2707 node);
2708
2709 ret = create_ust_app_channel_context(ua_sess, ua_chan, &uctx->ctx, app);
2710 if (ret < 0) {
2711 continue;
2712 }
2713 }
2714
2715 rcu_read_unlock();
2716 return ret;
2717 }
2718
2719 /*
2720 * Enable event for a channel from a UST session for a specific PID.
2721 */
2722 int ust_app_enable_event_pid(struct ltt_ust_session *usess,
2723 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent, pid_t pid)
2724 {
2725 int ret = 0;
2726 struct lttng_ht_iter iter;
2727 struct lttng_ht_node_str *ua_chan_node;
2728 struct ust_app *app;
2729 struct ust_app_session *ua_sess;
2730 struct ust_app_channel *ua_chan;
2731 struct ust_app_event *ua_event;
2732
2733 DBG("UST app enabling event %s for PID %d", uevent->attr.name, pid);
2734
2735 rcu_read_lock();
2736
2737 app = ust_app_find_by_pid(pid);
2738 if (app == NULL) {
2739 ERR("UST app enable event per PID %d not found", pid);
2740 ret = -1;
2741 goto error;
2742 }
2743
2744 if (!app->compatible) {
2745 ret = 0;
2746 goto error;
2747 }
2748
2749 ua_sess = lookup_session_by_app(usess, app);
2750 if (!ua_sess) {
2751 /* The application has problem or is probably dead. */
2752 goto error;
2753 }
2754
2755 /* Lookup channel in the ust app session */
2756 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
2757 ua_chan_node = lttng_ht_iter_get_node_str(&iter);
2758 /* If the channel is not found, there is a code flow error */
2759 assert(ua_chan_node);
2760
2761 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
2762
2763 ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name,
2764 uevent->filter, uevent->attr.loglevel);
2765 if (ua_event == NULL) {
2766 ret = create_ust_app_event(ua_sess, ua_chan, uevent, app);
2767 if (ret < 0) {
2768 goto error;
2769 }
2770 } else {
2771 ret = enable_ust_app_event(ua_sess, ua_event, app);
2772 if (ret < 0) {
2773 goto error;
2774 }
2775 }
2776
2777 error:
2778 rcu_read_unlock();
2779 return ret;
2780 }
2781
2782 /*
2783 * Disable event for a channel from a UST session for a specific PID.
2784 */
2785 int ust_app_disable_event_pid(struct ltt_ust_session *usess,
2786 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent, pid_t pid)
2787 {
2788 int ret = 0;
2789 struct lttng_ht_iter iter;
2790 struct lttng_ht_node_str *ua_chan_node, *ua_event_node;
2791 struct ust_app *app;
2792 struct ust_app_session *ua_sess;
2793 struct ust_app_channel *ua_chan;
2794 struct ust_app_event *ua_event;
2795
2796 DBG("UST app disabling event %s for PID %d", uevent->attr.name, pid);
2797
2798 rcu_read_lock();
2799
2800 app = ust_app_find_by_pid(pid);
2801 if (app == NULL) {
2802 ERR("UST app disable event per PID %d not found", pid);
2803 ret = -1;
2804 goto error;
2805 }
2806
2807 if (!app->compatible) {
2808 ret = 0;
2809 goto error;
2810 }
2811
2812 ua_sess = lookup_session_by_app(usess, app);
2813 if (!ua_sess) {
2814 /* The application has problem or is probably dead. */
2815 goto error;
2816 }
2817
2818 /* Lookup channel in the ust app session */
2819 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
2820 ua_chan_node = lttng_ht_iter_get_node_str(&iter);
2821 if (ua_chan_node == NULL) {
2822 /* Channel does not exist, skip disabling */
2823 goto error;
2824 }
2825 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
2826
2827 lttng_ht_lookup(ua_chan->events, (void *)uevent->attr.name, &iter);
2828 ua_event_node = lttng_ht_iter_get_node_str(&iter);
2829 if (ua_event_node == NULL) {
2830 /* Event does not exist, skip disabling */
2831 goto error;
2832 }
2833 ua_event = caa_container_of(ua_event_node, struct ust_app_event, node);
2834
2835 ret = disable_ust_app_event(ua_sess, ua_event, app);
2836 if (ret < 0) {
2837 goto error;
2838 }
2839
2840 error:
2841 rcu_read_unlock();
2842 return ret;
2843 }
2844
2845 /*
2846 * Validate version of UST apps and set the compatible bit.
2847 */
2848 int ust_app_validate_version(int sock)
2849 {
2850 int ret;
2851 struct ust_app *app;
2852
2853 rcu_read_lock();
2854
2855 app = find_app_by_sock(sock);
2856 assert(app);
2857
2858 health_code_update(&health_thread_cmd);
2859
2860 ret = ustctl_tracer_version(sock, &app->version);
2861 if (ret < 0) {
2862 goto error;
2863 }
2864
2865 /* Validate version */
2866 if (app->version.major != UST_APP_MAJOR_VERSION) {
2867 goto error;
2868 }
2869
2870 DBG2("UST app PID %d is compatible with internal major version %d "
2871 "(supporting == %d)", app->pid, app->version.major,
2872 UST_APP_MAJOR_VERSION);
2873 app->compatible = 1;
2874 rcu_read_unlock();
2875 health_code_update(&health_thread_cmd);
2876 return 0;
2877
2878 error:
2879 DBG2("UST app PID %d is not compatible with internal major version %d "
2880 "(supporting == %d)", app->pid, app->version.major,
2881 UST_APP_MAJOR_VERSION);
2882 app->compatible = 0;
2883 rcu_read_unlock();
2884 health_code_update(&health_thread_cmd);
2885 return -1;
2886 }
2887
2888 /*
2889 * Calibrate registered applications.
2890 */
2891 int ust_app_calibrate_glb(struct lttng_ust_calibrate *calibrate)
2892 {
2893 int ret = 0;
2894 struct lttng_ht_iter iter;
2895 struct ust_app *app;
2896
2897 rcu_read_lock();
2898
2899 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
2900 if (!app->compatible) {
2901 /*
2902 * TODO: In time, we should notice the caller of this error by
2903 * telling him that this is a version error.
2904 */
2905 continue;
2906 }
2907
2908 health_code_update(&health_thread_cmd);
2909
2910 ret = ustctl_calibrate(app->sock, calibrate);
2911 if (ret < 0) {
2912 switch (ret) {
2913 case -ENOSYS:
2914 /* Means that it's not implemented on the tracer side. */
2915 ret = 0;
2916 break;
2917 default:
2918 /* TODO: Report error to user */
2919 DBG2("Calibrate app PID %d returned with error %d",
2920 app->pid, ret);
2921 break;
2922 }
2923 }
2924 }
2925
2926 DBG("UST app global domain calibration finished");
2927
2928 rcu_read_unlock();
2929
2930 health_code_update(&health_thread_cmd);
2931
2932 return ret;
2933 }
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