Cleanup: app is never used by alloc_ust_app_session()
[lttng-tools.git] / src / bin / lttng-sessiond / ust-app.c
CommitLineData
91d76f53
DG
1/*
2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
bdf64013 3 * Copyright (C) 2016 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
91d76f53 4 *
d14d33bf
AM
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License, version 2 only,
7 * as published by the Free Software Foundation.
91d76f53
DG
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
d14d33bf
AM
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
91d76f53
DG
17 */
18
6c1c0768 19#define _LGPL_SOURCE
91d76f53 20#include <errno.h>
7972aab2 21#include <inttypes.h>
91d76f53
DG
22#include <pthread.h>
23#include <stdio.h>
24#include <stdlib.h>
099e26bd 25#include <string.h>
aba8e916
DG
26#include <sys/stat.h>
27#include <sys/types.h>
099e26bd 28#include <unistd.h>
0df502fd 29#include <urcu/compiler.h>
fb54cdbf 30#include <lttng/ust-error.h>
331744e3 31#include <signal.h>
bec39940 32
990570ed 33#include <common/common.h>
86acf0da 34#include <common/sessiond-comm/sessiond-comm.h>
1e307fab 35
7972aab2 36#include "buffer-registry.h"
86acf0da 37#include "fd-limit.h"
8782cc74 38#include "health-sessiond.h"
56fff090 39#include "ust-app.h"
48842b30 40#include "ust-consumer.h"
d80a6244 41#include "ust-ctl.h"
0b2dc8df 42#include "utils.h"
fb83fe64 43#include "session.h"
e9404c27
JG
44#include "lttng-sessiond.h"
45#include "notification-thread-commands.h"
5c408ad8 46#include "rotate.h"
d80a6244 47
c4b88406
MD
48static
49int ust_app_flush_app_session(struct ust_app *app, struct ust_app_session *ua_sess);
50
d9bf3ca4
MD
51/* Next available channel key. Access under next_channel_key_lock. */
52static uint64_t _next_channel_key;
53static pthread_mutex_t next_channel_key_lock = PTHREAD_MUTEX_INITIALIZER;
54
55/* Next available session ID. Access under next_session_id_lock. */
56static uint64_t _next_session_id;
57static pthread_mutex_t next_session_id_lock = PTHREAD_MUTEX_INITIALIZER;
ffe60014
DG
58
59/*
d9bf3ca4 60 * Return the incremented value of next_channel_key.
ffe60014 61 */
d9bf3ca4 62static uint64_t get_next_channel_key(void)
ffe60014 63{
d9bf3ca4
MD
64 uint64_t ret;
65
66 pthread_mutex_lock(&next_channel_key_lock);
67 ret = ++_next_channel_key;
68 pthread_mutex_unlock(&next_channel_key_lock);
69 return ret;
ffe60014
DG
70}
71
72/*
7972aab2 73 * Return the atomically incremented value of next_session_id.
ffe60014 74 */
d9bf3ca4 75static uint64_t get_next_session_id(void)
ffe60014 76{
d9bf3ca4
MD
77 uint64_t ret;
78
79 pthread_mutex_lock(&next_session_id_lock);
80 ret = ++_next_session_id;
81 pthread_mutex_unlock(&next_session_id_lock);
82 return ret;
ffe60014
DG
83}
84
d65d2de8
DG
85static void copy_channel_attr_to_ustctl(
86 struct ustctl_consumer_channel_attr *attr,
87 struct lttng_ust_channel_attr *uattr)
88{
89 /* Copy event attributes since the layout is different. */
90 attr->subbuf_size = uattr->subbuf_size;
91 attr->num_subbuf = uattr->num_subbuf;
92 attr->overwrite = uattr->overwrite;
93 attr->switch_timer_interval = uattr->switch_timer_interval;
94 attr->read_timer_interval = uattr->read_timer_interval;
95 attr->output = uattr->output;
491d1539 96 attr->blocking_timeout = uattr->u.s.blocking_timeout;
d65d2de8
DG
97}
98
025faf73
DG
99/*
100 * Match function for the hash table lookup.
101 *
102 * It matches an ust app event based on three attributes which are the event
103 * name, the filter bytecode and the loglevel.
104 */
18eace3b
DG
105static int ht_match_ust_app_event(struct cds_lfht_node *node, const void *_key)
106{
107 struct ust_app_event *event;
108 const struct ust_app_ht_key *key;
2106efa0 109 int ev_loglevel_value;
18eace3b
DG
110
111 assert(node);
112 assert(_key);
113
114 event = caa_container_of(node, struct ust_app_event, node.node);
115 key = _key;
2106efa0 116 ev_loglevel_value = event->attr.loglevel;
18eace3b 117
1af53eb5 118 /* Match the 4 elements of the key: name, filter, loglevel, exclusions */
18eace3b
DG
119
120 /* Event name */
121 if (strncmp(event->attr.name, key->name, sizeof(event->attr.name)) != 0) {
122 goto no_match;
123 }
124
125 /* Event loglevel. */
2106efa0 126 if (ev_loglevel_value != key->loglevel_type) {
025faf73 127 if (event->attr.loglevel_type == LTTNG_UST_LOGLEVEL_ALL
2106efa0
PP
128 && key->loglevel_type == 0 &&
129 ev_loglevel_value == -1) {
025faf73
DG
130 /*
131 * Match is accepted. This is because on event creation, the
132 * loglevel is set to -1 if the event loglevel type is ALL so 0 and
133 * -1 are accepted for this loglevel type since 0 is the one set by
134 * the API when receiving an enable event.
135 */
136 } else {
137 goto no_match;
138 }
18eace3b
DG
139 }
140
141 /* One of the filters is NULL, fail. */
142 if ((key->filter && !event->filter) || (!key->filter && event->filter)) {
143 goto no_match;
144 }
145
025faf73
DG
146 if (key->filter && event->filter) {
147 /* Both filters exists, check length followed by the bytecode. */
148 if (event->filter->len != key->filter->len ||
149 memcmp(event->filter->data, key->filter->data,
150 event->filter->len) != 0) {
151 goto no_match;
152 }
18eace3b
DG
153 }
154
1af53eb5
JI
155 /* One of the exclusions is NULL, fail. */
156 if ((key->exclusion && !event->exclusion) || (!key->exclusion && event->exclusion)) {
157 goto no_match;
158 }
159
160 if (key->exclusion && event->exclusion) {
161 /* Both exclusions exists, check count followed by the names. */
162 if (event->exclusion->count != key->exclusion->count ||
163 memcmp(event->exclusion->names, key->exclusion->names,
164 event->exclusion->count * LTTNG_UST_SYM_NAME_LEN) != 0) {
165 goto no_match;
166 }
167 }
168
169
025faf73 170 /* Match. */
18eace3b
DG
171 return 1;
172
173no_match:
174 return 0;
18eace3b
DG
175}
176
025faf73
DG
177/*
178 * Unique add of an ust app event in the given ht. This uses the custom
179 * ht_match_ust_app_event match function and the event name as hash.
180 */
d0b96690 181static void add_unique_ust_app_event(struct ust_app_channel *ua_chan,
18eace3b
DG
182 struct ust_app_event *event)
183{
184 struct cds_lfht_node *node_ptr;
185 struct ust_app_ht_key key;
d0b96690 186 struct lttng_ht *ht;
18eace3b 187
d0b96690
DG
188 assert(ua_chan);
189 assert(ua_chan->events);
18eace3b
DG
190 assert(event);
191
d0b96690 192 ht = ua_chan->events;
18eace3b
DG
193 key.name = event->attr.name;
194 key.filter = event->filter;
2106efa0 195 key.loglevel_type = event->attr.loglevel;
91c89f23 196 key.exclusion = event->exclusion;
18eace3b
DG
197
198 node_ptr = cds_lfht_add_unique(ht->ht,
199 ht->hash_fct(event->node.key, lttng_ht_seed),
200 ht_match_ust_app_event, &key, &event->node.node);
201 assert(node_ptr == &event->node.node);
202}
203
d88aee68
DG
204/*
205 * Close the notify socket from the given RCU head object. This MUST be called
206 * through a call_rcu().
207 */
208static void close_notify_sock_rcu(struct rcu_head *head)
209{
210 int ret;
211 struct ust_app_notify_sock_obj *obj =
212 caa_container_of(head, struct ust_app_notify_sock_obj, head);
213
214 /* Must have a valid fd here. */
215 assert(obj->fd >= 0);
216
217 ret = close(obj->fd);
218 if (ret) {
219 ERR("close notify sock %d RCU", obj->fd);
220 }
221 lttng_fd_put(LTTNG_FD_APPS, 1);
222
223 free(obj);
224}
225
7972aab2
DG
226/*
227 * Return the session registry according to the buffer type of the given
228 * session.
229 *
230 * A registry per UID object MUST exists before calling this function or else
231 * it assert() if not found. RCU read side lock must be acquired.
232 */
233static struct ust_registry_session *get_session_registry(
234 struct ust_app_session *ua_sess)
235{
236 struct ust_registry_session *registry = NULL;
237
238 assert(ua_sess);
239
240 switch (ua_sess->buffer_type) {
241 case LTTNG_BUFFER_PER_PID:
242 {
243 struct buffer_reg_pid *reg_pid = buffer_reg_pid_find(ua_sess->id);
244 if (!reg_pid) {
245 goto error;
246 }
247 registry = reg_pid->registry->reg.ust;
248 break;
249 }
250 case LTTNG_BUFFER_PER_UID:
251 {
252 struct buffer_reg_uid *reg_uid = buffer_reg_uid_find(
253 ua_sess->tracing_id, ua_sess->bits_per_long, ua_sess->uid);
254 if (!reg_uid) {
255 goto error;
256 }
257 registry = reg_uid->registry->reg.ust;
258 break;
259 }
260 default:
261 assert(0);
262 };
263
264error:
265 return registry;
266}
267
55cc08a6
DG
268/*
269 * Delete ust context safely. RCU read lock must be held before calling
270 * this function.
271 */
272static
fb45065e
MD
273void delete_ust_app_ctx(int sock, struct ust_app_ctx *ua_ctx,
274 struct ust_app *app)
55cc08a6 275{
ffe60014
DG
276 int ret;
277
278 assert(ua_ctx);
279
55cc08a6 280 if (ua_ctx->obj) {
fb45065e 281 pthread_mutex_lock(&app->sock_lock);
ffe60014 282 ret = ustctl_release_object(sock, ua_ctx->obj);
fb45065e 283 pthread_mutex_unlock(&app->sock_lock);
d0b96690
DG
284 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
285 ERR("UST app sock %d release ctx obj handle %d failed with ret %d",
286 sock, ua_ctx->obj->handle, ret);
ffe60014 287 }
55cc08a6
DG
288 free(ua_ctx->obj);
289 }
290 free(ua_ctx);
291}
292
d80a6244
DG
293/*
294 * Delete ust app event safely. RCU read lock must be held before calling
295 * this function.
296 */
8b366481 297static
fb45065e
MD
298void delete_ust_app_event(int sock, struct ust_app_event *ua_event,
299 struct ust_app *app)
d80a6244 300{
ffe60014
DG
301 int ret;
302
303 assert(ua_event);
304
53a80697 305 free(ua_event->filter);
951f0b71
JI
306 if (ua_event->exclusion != NULL)
307 free(ua_event->exclusion);
edb67388 308 if (ua_event->obj != NULL) {
fb45065e 309 pthread_mutex_lock(&app->sock_lock);
ffe60014 310 ret = ustctl_release_object(sock, ua_event->obj);
fb45065e 311 pthread_mutex_unlock(&app->sock_lock);
ffe60014
DG
312 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
313 ERR("UST app sock %d release event obj failed with ret %d",
314 sock, ret);
315 }
edb67388
DG
316 free(ua_event->obj);
317 }
d80a6244
DG
318 free(ua_event);
319}
320
321/*
7972aab2
DG
322 * Release ust data object of the given stream.
323 *
324 * Return 0 on success or else a negative value.
d80a6244 325 */
fb45065e
MD
326static int release_ust_app_stream(int sock, struct ust_app_stream *stream,
327 struct ust_app *app)
d80a6244 328{
7972aab2 329 int ret = 0;
ffe60014
DG
330
331 assert(stream);
332
8b366481 333 if (stream->obj) {
fb45065e 334 pthread_mutex_lock(&app->sock_lock);
ffe60014 335 ret = ustctl_release_object(sock, stream->obj);
fb45065e 336 pthread_mutex_unlock(&app->sock_lock);
ffe60014
DG
337 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
338 ERR("UST app sock %d release stream obj failed with ret %d",
339 sock, ret);
340 }
4063050c 341 lttng_fd_put(LTTNG_FD_APPS, 2);
8b366481
DG
342 free(stream->obj);
343 }
7972aab2
DG
344
345 return ret;
346}
347
348/*
349 * Delete ust app stream safely. RCU read lock must be held before calling
350 * this function.
351 */
352static
fb45065e
MD
353void delete_ust_app_stream(int sock, struct ust_app_stream *stream,
354 struct ust_app *app)
7972aab2
DG
355{
356 assert(stream);
357
fb45065e 358 (void) release_ust_app_stream(sock, stream, app);
84cd17c6 359 free(stream);
d80a6244
DG
360}
361
36b588ed
MD
362/*
363 * We need to execute ht_destroy outside of RCU read-side critical
0b2dc8df
MD
364 * section and outside of call_rcu thread, so we postpone its execution
365 * using ht_cleanup_push. It is simpler than to change the semantic of
366 * the many callers of delete_ust_app_session().
36b588ed
MD
367 */
368static
369void delete_ust_app_channel_rcu(struct rcu_head *head)
370{
371 struct ust_app_channel *ua_chan =
372 caa_container_of(head, struct ust_app_channel, rcu_head);
373
0b2dc8df
MD
374 ht_cleanup_push(ua_chan->ctx);
375 ht_cleanup_push(ua_chan->events);
36b588ed
MD
376 free(ua_chan);
377}
378
fb83fe64
JD
379/*
380 * Extract the lost packet or discarded events counter when the channel is
381 * being deleted and store the value in the parent channel so we can
382 * access it from lttng list and at stop/destroy.
82cac6d2
JG
383 *
384 * The session list lock must be held by the caller.
fb83fe64
JD
385 */
386static
387void save_per_pid_lost_discarded_counters(struct ust_app_channel *ua_chan)
388{
389 uint64_t discarded = 0, lost = 0;
390 struct ltt_session *session;
391 struct ltt_ust_channel *uchan;
392
393 if (ua_chan->attr.type != LTTNG_UST_CHAN_PER_CPU) {
394 return;
395 }
396
397 rcu_read_lock();
398 session = session_find_by_id(ua_chan->session->tracing_id);
d68ec974
JG
399 if (!session || !session->ust_session) {
400 /*
401 * Not finding the session is not an error because there are
402 * multiple ways the channels can be torn down.
403 *
404 * 1) The session daemon can initiate the destruction of the
405 * ust app session after receiving a destroy command or
406 * during its shutdown/teardown.
407 * 2) The application, since we are in per-pid tracing, is
408 * unregistering and tearing down its ust app session.
409 *
410 * Both paths are protected by the session list lock which
411 * ensures that the accounting of lost packets and discarded
412 * events is done exactly once. The session is then unpublished
413 * from the session list, resulting in this condition.
414 */
fb83fe64
JD
415 goto end;
416 }
417
418 if (ua_chan->attr.overwrite) {
419 consumer_get_lost_packets(ua_chan->session->tracing_id,
420 ua_chan->key, session->ust_session->consumer,
421 &lost);
422 } else {
423 consumer_get_discarded_events(ua_chan->session->tracing_id,
424 ua_chan->key, session->ust_session->consumer,
425 &discarded);
426 }
427 uchan = trace_ust_find_channel_by_name(
428 session->ust_session->domain_global.channels,
429 ua_chan->name);
430 if (!uchan) {
431 ERR("Missing UST channel to store discarded counters");
432 goto end;
433 }
434
435 uchan->per_pid_closed_app_discarded += discarded;
436 uchan->per_pid_closed_app_lost += lost;
437
438end:
439 rcu_read_unlock();
440}
441
d80a6244
DG
442/*
443 * Delete ust app channel safely. RCU read lock must be held before calling
444 * this function.
82cac6d2
JG
445 *
446 * The session list lock must be held by the caller.
d80a6244 447 */
8b366481 448static
d0b96690
DG
449void delete_ust_app_channel(int sock, struct ust_app_channel *ua_chan,
450 struct ust_app *app)
d80a6244
DG
451{
452 int ret;
bec39940 453 struct lttng_ht_iter iter;
d80a6244 454 struct ust_app_event *ua_event;
55cc08a6 455 struct ust_app_ctx *ua_ctx;
030a66fa 456 struct ust_app_stream *stream, *stmp;
7972aab2 457 struct ust_registry_session *registry;
d80a6244 458
ffe60014
DG
459 assert(ua_chan);
460
461 DBG3("UST app deleting channel %s", ua_chan->name);
462
55cc08a6 463 /* Wipe stream */
d80a6244 464 cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
84cd17c6 465 cds_list_del(&stream->list);
fb45065e 466 delete_ust_app_stream(sock, stream, app);
d80a6244
DG
467 }
468
55cc08a6 469 /* Wipe context */
bec39940 470 cds_lfht_for_each_entry(ua_chan->ctx->ht, &iter.iter, ua_ctx, node.node) {
31746f93 471 cds_list_del(&ua_ctx->list);
bec39940 472 ret = lttng_ht_del(ua_chan->ctx, &iter);
55cc08a6 473 assert(!ret);
fb45065e 474 delete_ust_app_ctx(sock, ua_ctx, app);
55cc08a6 475 }
d80a6244 476
55cc08a6 477 /* Wipe events */
bec39940
DG
478 cds_lfht_for_each_entry(ua_chan->events->ht, &iter.iter, ua_event,
479 node.node) {
480 ret = lttng_ht_del(ua_chan->events, &iter);
525b0740 481 assert(!ret);
fb45065e 482 delete_ust_app_event(sock, ua_event, app);
d80a6244 483 }
edb67388 484
c8335706
MD
485 if (ua_chan->session->buffer_type == LTTNG_BUFFER_PER_PID) {
486 /* Wipe and free registry from session registry. */
487 registry = get_session_registry(ua_chan->session);
488 if (registry) {
e9404c27
JG
489 ust_registry_channel_del_free(registry, ua_chan->key,
490 true);
c8335706 491 }
fb83fe64 492 save_per_pid_lost_discarded_counters(ua_chan);
7972aab2 493 }
d0b96690 494
edb67388 495 if (ua_chan->obj != NULL) {
d0b96690
DG
496 /* Remove channel from application UST object descriptor. */
497 iter.iter.node = &ua_chan->ust_objd_node.node;
c6e62271
DG
498 ret = lttng_ht_del(app->ust_objd, &iter);
499 assert(!ret);
fb45065e 500 pthread_mutex_lock(&app->sock_lock);
ffe60014 501 ret = ustctl_release_object(sock, ua_chan->obj);
fb45065e 502 pthread_mutex_unlock(&app->sock_lock);
ffe60014
DG
503 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
504 ERR("UST app sock %d release channel obj failed with ret %d",
505 sock, ret);
506 }
7972aab2 507 lttng_fd_put(LTTNG_FD_APPS, 1);
edb67388
DG
508 free(ua_chan->obj);
509 }
36b588ed 510 call_rcu(&ua_chan->rcu_head, delete_ust_app_channel_rcu);
d80a6244
DG
511}
512
fb45065e
MD
513int ust_app_register_done(struct ust_app *app)
514{
515 int ret;
516
517 pthread_mutex_lock(&app->sock_lock);
518 ret = ustctl_register_done(app->sock);
519 pthread_mutex_unlock(&app->sock_lock);
520 return ret;
521}
522
523int ust_app_release_object(struct ust_app *app, struct lttng_ust_object_data *data)
524{
525 int ret, sock;
526
527 if (app) {
528 pthread_mutex_lock(&app->sock_lock);
529 sock = app->sock;
530 } else {
531 sock = -1;
532 }
533 ret = ustctl_release_object(sock, data);
534 if (app) {
535 pthread_mutex_unlock(&app->sock_lock);
536 }
537 return ret;
538}
539
331744e3 540/*
1b532a60
DG
541 * Push metadata to consumer socket.
542 *
dc2bbdae
MD
543 * RCU read-side lock must be held to guarantee existance of socket.
544 * Must be called with the ust app session lock held.
545 * Must be called with the registry lock held.
331744e3
JD
546 *
547 * On success, return the len of metadata pushed or else a negative value.
2c57e06d
MD
548 * Returning a -EPIPE return value means we could not send the metadata,
549 * but it can be caused by recoverable errors (e.g. the application has
550 * terminated concurrently).
331744e3
JD
551 */
552ssize_t ust_app_push_metadata(struct ust_registry_session *registry,
553 struct consumer_socket *socket, int send_zero_data)
554{
555 int ret;
556 char *metadata_str = NULL;
c585821b 557 size_t len, offset, new_metadata_len_sent;
331744e3 558 ssize_t ret_val;
93ec662e 559 uint64_t metadata_key, metadata_version;
331744e3
JD
560
561 assert(registry);
562 assert(socket);
1b532a60 563
c585821b
MD
564 metadata_key = registry->metadata_key;
565
ce34fcd0 566 /*
dc2bbdae
MD
567 * Means that no metadata was assigned to the session. This can
568 * happens if no start has been done previously.
ce34fcd0 569 */
c585821b 570 if (!metadata_key) {
ce34fcd0
MD
571 return 0;
572 }
573
331744e3
JD
574 offset = registry->metadata_len_sent;
575 len = registry->metadata_len - registry->metadata_len_sent;
c585821b 576 new_metadata_len_sent = registry->metadata_len;
93ec662e 577 metadata_version = registry->metadata_version;
331744e3
JD
578 if (len == 0) {
579 DBG3("No metadata to push for metadata key %" PRIu64,
580 registry->metadata_key);
581 ret_val = len;
582 if (send_zero_data) {
583 DBG("No metadata to push");
584 goto push_data;
585 }
586 goto end;
587 }
588
589 /* Allocate only what we have to send. */
590 metadata_str = zmalloc(len);
591 if (!metadata_str) {
592 PERROR("zmalloc ust app metadata string");
593 ret_val = -ENOMEM;
594 goto error;
595 }
c585821b 596 /* Copy what we haven't sent out. */
331744e3 597 memcpy(metadata_str, registry->metadata + offset, len);
331744e3
JD
598
599push_data:
c585821b
MD
600 pthread_mutex_unlock(&registry->lock);
601 /*
602 * We need to unlock the registry while we push metadata to
603 * break a circular dependency between the consumerd metadata
604 * lock and the sessiond registry lock. Indeed, pushing metadata
605 * to the consumerd awaits that it gets pushed all the way to
606 * relayd, but doing so requires grabbing the metadata lock. If
607 * a concurrent metadata request is being performed by
608 * consumerd, this can try to grab the registry lock on the
609 * sessiond while holding the metadata lock on the consumer
610 * daemon. Those push and pull schemes are performed on two
611 * different bidirectionnal communication sockets.
612 */
613 ret = consumer_push_metadata(socket, metadata_key,
93ec662e 614 metadata_str, len, offset, metadata_version);
c585821b 615 pthread_mutex_lock(&registry->lock);
331744e3 616 if (ret < 0) {
000baf6a 617 /*
dc2bbdae
MD
618 * There is an acceptable race here between the registry
619 * metadata key assignment and the creation on the
620 * consumer. The session daemon can concurrently push
621 * metadata for this registry while being created on the
622 * consumer since the metadata key of the registry is
623 * assigned *before* it is setup to avoid the consumer
624 * to ask for metadata that could possibly be not found
625 * in the session daemon.
000baf6a 626 *
dc2bbdae
MD
627 * The metadata will get pushed either by the session
628 * being stopped or the consumer requesting metadata if
629 * that race is triggered.
000baf6a
DG
630 */
631 if (ret == -LTTCOMM_CONSUMERD_CHANNEL_FAIL) {
632 ret = 0;
c585821b
MD
633 } else {
634 ERR("Error pushing metadata to consumer");
000baf6a 635 }
331744e3
JD
636 ret_val = ret;
637 goto error_push;
c585821b
MD
638 } else {
639 /*
640 * Metadata may have been concurrently pushed, since
641 * we're not holding the registry lock while pushing to
642 * consumer. This is handled by the fact that we send
643 * the metadata content, size, and the offset at which
644 * that metadata belongs. This may arrive out of order
645 * on the consumer side, and the consumer is able to
646 * deal with overlapping fragments. The consumer
647 * supports overlapping fragments, which must be
648 * contiguous starting from offset 0. We keep the
649 * largest metadata_len_sent value of the concurrent
650 * send.
651 */
652 registry->metadata_len_sent =
653 max_t(size_t, registry->metadata_len_sent,
654 new_metadata_len_sent);
331744e3 655 }
331744e3
JD
656 free(metadata_str);
657 return len;
658
659end:
660error:
ce34fcd0
MD
661 if (ret_val) {
662 /*
dc2bbdae
MD
663 * On error, flag the registry that the metadata is
664 * closed. We were unable to push anything and this
665 * means that either the consumer is not responding or
666 * the metadata cache has been destroyed on the
667 * consumer.
ce34fcd0
MD
668 */
669 registry->metadata_closed = 1;
670 }
331744e3
JD
671error_push:
672 free(metadata_str);
673 return ret_val;
674}
675
d88aee68 676/*
ce34fcd0 677 * For a given application and session, push metadata to consumer.
331744e3
JD
678 * Either sock or consumer is required : if sock is NULL, the default
679 * socket to send the metadata is retrieved from consumer, if sock
680 * is not NULL we use it to send the metadata.
ce34fcd0 681 * RCU read-side lock must be held while calling this function,
dc2bbdae
MD
682 * therefore ensuring existance of registry. It also ensures existance
683 * of socket throughout this function.
d88aee68
DG
684 *
685 * Return 0 on success else a negative error.
2c57e06d
MD
686 * Returning a -EPIPE return value means we could not send the metadata,
687 * but it can be caused by recoverable errors (e.g. the application has
688 * terminated concurrently).
d88aee68 689 */
7972aab2
DG
690static int push_metadata(struct ust_registry_session *registry,
691 struct consumer_output *consumer)
d88aee68 692{
331744e3
JD
693 int ret_val;
694 ssize_t ret;
d88aee68
DG
695 struct consumer_socket *socket;
696
7972aab2
DG
697 assert(registry);
698 assert(consumer);
699
ce34fcd0 700 pthread_mutex_lock(&registry->lock);
ce34fcd0 701 if (registry->metadata_closed) {
dc2bbdae
MD
702 ret_val = -EPIPE;
703 goto error;
d88aee68
DG
704 }
705
d88aee68 706 /* Get consumer socket to use to push the metadata.*/
7972aab2
DG
707 socket = consumer_find_socket_by_bitness(registry->bits_per_long,
708 consumer);
d88aee68 709 if (!socket) {
331744e3 710 ret_val = -1;
ce34fcd0 711 goto error;
d88aee68
DG
712 }
713
331744e3 714 ret = ust_app_push_metadata(registry, socket, 0);
d88aee68 715 if (ret < 0) {
331744e3 716 ret_val = ret;
ce34fcd0 717 goto error;
d88aee68 718 }
dc2bbdae 719 pthread_mutex_unlock(&registry->lock);
d88aee68
DG
720 return 0;
721
ce34fcd0 722error:
dc2bbdae 723 pthread_mutex_unlock(&registry->lock);
331744e3 724 return ret_val;
d88aee68
DG
725}
726
727/*
728 * Send to the consumer a close metadata command for the given session. Once
729 * done, the metadata channel is deleted and the session metadata pointer is
dc2bbdae 730 * nullified. The session lock MUST be held unless the application is
d88aee68
DG
731 * in the destroy path.
732 *
733 * Return 0 on success else a negative value.
734 */
7972aab2
DG
735static int close_metadata(struct ust_registry_session *registry,
736 struct consumer_output *consumer)
d88aee68
DG
737{
738 int ret;
739 struct consumer_socket *socket;
740
7972aab2
DG
741 assert(registry);
742 assert(consumer);
d88aee68 743
7972aab2
DG
744 rcu_read_lock();
745
ce34fcd0
MD
746 pthread_mutex_lock(&registry->lock);
747
7972aab2 748 if (!registry->metadata_key || registry->metadata_closed) {
d88aee68 749 ret = 0;
1b532a60 750 goto end;
d88aee68
DG
751 }
752
d88aee68 753 /* Get consumer socket to use to push the metadata.*/
7972aab2
DG
754 socket = consumer_find_socket_by_bitness(registry->bits_per_long,
755 consumer);
d88aee68
DG
756 if (!socket) {
757 ret = -1;
7972aab2 758 goto error;
d88aee68
DG
759 }
760
7972aab2 761 ret = consumer_close_metadata(socket, registry->metadata_key);
d88aee68 762 if (ret < 0) {
7972aab2 763 goto error;
d88aee68
DG
764 }
765
d88aee68 766error:
1b532a60
DG
767 /*
768 * Metadata closed. Even on error this means that the consumer is not
769 * responding or not found so either way a second close should NOT be emit
770 * for this registry.
771 */
772 registry->metadata_closed = 1;
773end:
ce34fcd0 774 pthread_mutex_unlock(&registry->lock);
7972aab2 775 rcu_read_unlock();
d88aee68
DG
776 return ret;
777}
778
36b588ed
MD
779/*
780 * We need to execute ht_destroy outside of RCU read-side critical
0b2dc8df
MD
781 * section and outside of call_rcu thread, so we postpone its execution
782 * using ht_cleanup_push. It is simpler than to change the semantic of
783 * the many callers of delete_ust_app_session().
36b588ed
MD
784 */
785static
786void delete_ust_app_session_rcu(struct rcu_head *head)
787{
788 struct ust_app_session *ua_sess =
789 caa_container_of(head, struct ust_app_session, rcu_head);
790
0b2dc8df 791 ht_cleanup_push(ua_sess->channels);
36b588ed
MD
792 free(ua_sess);
793}
794
d80a6244
DG
795/*
796 * Delete ust app session safely. RCU read lock must be held before calling
797 * this function.
82cac6d2
JG
798 *
799 * The session list lock must be held by the caller.
d80a6244 800 */
8b366481 801static
d0b96690
DG
802void delete_ust_app_session(int sock, struct ust_app_session *ua_sess,
803 struct ust_app *app)
d80a6244
DG
804{
805 int ret;
bec39940 806 struct lttng_ht_iter iter;
d80a6244 807 struct ust_app_channel *ua_chan;
7972aab2 808 struct ust_registry_session *registry;
d80a6244 809
d88aee68
DG
810 assert(ua_sess);
811
1b532a60
DG
812 pthread_mutex_lock(&ua_sess->lock);
813
b161602a
MD
814 assert(!ua_sess->deleted);
815 ua_sess->deleted = true;
816
7972aab2 817 registry = get_session_registry(ua_sess);
fad1ed2f 818 /* Registry can be null on error path during initialization. */
ce34fcd0 819 if (registry) {
d88aee68 820 /* Push metadata for application before freeing the application. */
7972aab2 821 (void) push_metadata(registry, ua_sess->consumer);
d88aee68 822
7972aab2
DG
823 /*
824 * Don't ask to close metadata for global per UID buffers. Close
1b532a60
DG
825 * metadata only on destroy trace session in this case. Also, the
826 * previous push metadata could have flag the metadata registry to
827 * close so don't send a close command if closed.
7972aab2 828 */
ce34fcd0 829 if (ua_sess->buffer_type != LTTNG_BUFFER_PER_UID) {
7972aab2
DG
830 /* And ask to close it for this session registry. */
831 (void) close_metadata(registry, ua_sess->consumer);
832 }
d80a6244
DG
833 }
834
bec39940
DG
835 cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
836 node.node) {
837 ret = lttng_ht_del(ua_sess->channels, &iter);
525b0740 838 assert(!ret);
d0b96690 839 delete_ust_app_channel(sock, ua_chan, app);
d80a6244 840 }
d80a6244 841
7972aab2
DG
842 /* In case of per PID, the registry is kept in the session. */
843 if (ua_sess->buffer_type == LTTNG_BUFFER_PER_PID) {
844 struct buffer_reg_pid *reg_pid = buffer_reg_pid_find(ua_sess->id);
845 if (reg_pid) {
fad1ed2f
JR
846 /*
847 * Registry can be null on error path during
848 * initialization.
849 */
7972aab2
DG
850 buffer_reg_pid_remove(reg_pid);
851 buffer_reg_pid_destroy(reg_pid);
852 }
853 }
d0b96690 854
aee6bafd 855 if (ua_sess->handle != -1) {
fb45065e 856 pthread_mutex_lock(&app->sock_lock);
ffe60014 857 ret = ustctl_release_handle(sock, ua_sess->handle);
fb45065e 858 pthread_mutex_unlock(&app->sock_lock);
ffe60014
DG
859 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
860 ERR("UST app sock %d release session handle failed with ret %d",
861 sock, ret);
862 }
10b56aef
MD
863 /* Remove session from application UST object descriptor. */
864 iter.iter.node = &ua_sess->ust_objd_node.node;
865 ret = lttng_ht_del(app->ust_sessions_objd, &iter);
866 assert(!ret);
aee6bafd 867 }
10b56aef 868
1b532a60
DG
869 pthread_mutex_unlock(&ua_sess->lock);
870
6addfa37
MD
871 consumer_output_put(ua_sess->consumer);
872
36b588ed 873 call_rcu(&ua_sess->rcu_head, delete_ust_app_session_rcu);
d80a6244 874}
91d76f53
DG
875
876/*
284d8f55
DG
877 * Delete a traceable application structure from the global list. Never call
878 * this function outside of a call_rcu call.
36b588ed
MD
879 *
880 * RCU read side lock should _NOT_ be held when calling this function.
91d76f53 881 */
8b366481
DG
882static
883void delete_ust_app(struct ust_app *app)
91d76f53 884{
8b366481 885 int ret, sock;
d42f20df 886 struct ust_app_session *ua_sess, *tmp_ua_sess;
44d3bd01 887
82cac6d2
JG
888 /*
889 * The session list lock must be held during this function to guarantee
890 * the existence of ua_sess.
891 */
892 session_lock_list();
d80a6244 893 /* Delete ust app sessions info */
852d0037
DG
894 sock = app->sock;
895 app->sock = -1;
d80a6244 896
8b366481 897 /* Wipe sessions */
d42f20df
DG
898 cds_list_for_each_entry_safe(ua_sess, tmp_ua_sess, &app->teardown_head,
899 teardown_node) {
900 /* Free every object in the session and the session. */
36b588ed 901 rcu_read_lock();
d0b96690 902 delete_ust_app_session(sock, ua_sess, app);
36b588ed 903 rcu_read_unlock();
d80a6244 904 }
36b588ed 905
0b2dc8df 906 ht_cleanup_push(app->sessions);
10b56aef 907 ht_cleanup_push(app->ust_sessions_objd);
0b2dc8df 908 ht_cleanup_push(app->ust_objd);
d80a6244 909
6414a713 910 /*
852d0037
DG
911 * Wait until we have deleted the application from the sock hash table
912 * before closing this socket, otherwise an application could re-use the
913 * socket ID and race with the teardown, using the same hash table entry.
914 *
915 * It's OK to leave the close in call_rcu. We want it to stay unique for
916 * all RCU readers that could run concurrently with unregister app,
917 * therefore we _need_ to only close that socket after a grace period. So
918 * it should stay in this RCU callback.
919 *
920 * This close() is a very important step of the synchronization model so
921 * every modification to this function must be carefully reviewed.
6414a713 922 */
799e2c4f
MD
923 ret = close(sock);
924 if (ret) {
925 PERROR("close");
926 }
4063050c 927 lttng_fd_put(LTTNG_FD_APPS, 1);
d80a6244 928
852d0037 929 DBG2("UST app pid %d deleted", app->pid);
284d8f55 930 free(app);
82cac6d2 931 session_unlock_list();
099e26bd
DG
932}
933
934/*
f6a9efaa 935 * URCU intermediate call to delete an UST app.
099e26bd 936 */
8b366481
DG
937static
938void delete_ust_app_rcu(struct rcu_head *head)
099e26bd 939{
bec39940
DG
940 struct lttng_ht_node_ulong *node =
941 caa_container_of(head, struct lttng_ht_node_ulong, head);
f6a9efaa 942 struct ust_app *app =
852d0037 943 caa_container_of(node, struct ust_app, pid_n);
f6a9efaa 944
852d0037 945 DBG3("Call RCU deleting app PID %d", app->pid);
f6a9efaa 946 delete_ust_app(app);
099e26bd
DG
947}
948
ffe60014
DG
949/*
950 * Delete the session from the application ht and delete the data structure by
951 * freeing every object inside and releasing them.
82cac6d2
JG
952 *
953 * The session list lock must be held by the caller.
ffe60014 954 */
d0b96690 955static void destroy_app_session(struct ust_app *app,
ffe60014
DG
956 struct ust_app_session *ua_sess)
957{
958 int ret;
959 struct lttng_ht_iter iter;
960
961 assert(app);
962 assert(ua_sess);
963
964 iter.iter.node = &ua_sess->node.node;
965 ret = lttng_ht_del(app->sessions, &iter);
966 if (ret) {
967 /* Already scheduled for teardown. */
968 goto end;
969 }
970
971 /* Once deleted, free the data structure. */
d0b96690 972 delete_ust_app_session(app->sock, ua_sess, app);
ffe60014
DG
973
974end:
975 return;
976}
977
8b366481
DG
978/*
979 * Alloc new UST app session.
980 */
981static
40bbd087 982struct ust_app_session *alloc_ust_app_session(void)
8b366481
DG
983{
984 struct ust_app_session *ua_sess;
985
986 /* Init most of the default value by allocating and zeroing */
987 ua_sess = zmalloc(sizeof(struct ust_app_session));
988 if (ua_sess == NULL) {
989 PERROR("malloc");
ffe60014 990 goto error_free;
8b366481
DG
991 }
992
993 ua_sess->handle = -1;
bec39940 994 ua_sess->channels = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
ad7a9107 995 ua_sess->metadata_attr.type = LTTNG_UST_CHAN_METADATA;
84ad93e8 996 pthread_mutex_init(&ua_sess->lock, NULL);
ad7a9107 997
8b366481
DG
998 return ua_sess;
999
ffe60014 1000error_free:
8b366481
DG
1001 return NULL;
1002}
1003
1004/*
1005 * Alloc new UST app channel.
1006 */
1007static
1008struct ust_app_channel *alloc_ust_app_channel(char *name,
d0b96690 1009 struct ust_app_session *ua_sess,
ffe60014 1010 struct lttng_ust_channel_attr *attr)
8b366481
DG
1011{
1012 struct ust_app_channel *ua_chan;
1013
1014 /* Init most of the default value by allocating and zeroing */
1015 ua_chan = zmalloc(sizeof(struct ust_app_channel));
1016 if (ua_chan == NULL) {
1017 PERROR("malloc");
1018 goto error;
1019 }
1020
1021 /* Setup channel name */
1022 strncpy(ua_chan->name, name, sizeof(ua_chan->name));
1023 ua_chan->name[sizeof(ua_chan->name) - 1] = '\0';
1024
1025 ua_chan->enabled = 1;
1026 ua_chan->handle = -1;
45893984 1027 ua_chan->session = ua_sess;
ffe60014 1028 ua_chan->key = get_next_channel_key();
bec39940
DG
1029 ua_chan->ctx = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
1030 ua_chan->events = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
1031 lttng_ht_node_init_str(&ua_chan->node, ua_chan->name);
8b366481
DG
1032
1033 CDS_INIT_LIST_HEAD(&ua_chan->streams.head);
31746f93 1034 CDS_INIT_LIST_HEAD(&ua_chan->ctx_list);
8b366481
DG
1035
1036 /* Copy attributes */
1037 if (attr) {
ffe60014 1038 /* Translate from lttng_ust_channel to ustctl_consumer_channel_attr. */
2fe6e7f5
DG
1039 ua_chan->attr.subbuf_size = attr->subbuf_size;
1040 ua_chan->attr.num_subbuf = attr->num_subbuf;
1041 ua_chan->attr.overwrite = attr->overwrite;
1042 ua_chan->attr.switch_timer_interval = attr->switch_timer_interval;
1043 ua_chan->attr.read_timer_interval = attr->read_timer_interval;
1044 ua_chan->attr.output = attr->output;
491d1539 1045 ua_chan->attr.blocking_timeout = attr->u.s.blocking_timeout;
8b366481 1046 }
ffe60014
DG
1047 /* By default, the channel is a per cpu channel. */
1048 ua_chan->attr.type = LTTNG_UST_CHAN_PER_CPU;
8b366481
DG
1049
1050 DBG3("UST app channel %s allocated", ua_chan->name);
1051
1052 return ua_chan;
1053
1054error:
1055 return NULL;
1056}
1057
37f1c236
DG
1058/*
1059 * Allocate and initialize a UST app stream.
1060 *
1061 * Return newly allocated stream pointer or NULL on error.
1062 */
ffe60014 1063struct ust_app_stream *ust_app_alloc_stream(void)
37f1c236
DG
1064{
1065 struct ust_app_stream *stream = NULL;
1066
1067 stream = zmalloc(sizeof(*stream));
1068 if (stream == NULL) {
1069 PERROR("zmalloc ust app stream");
1070 goto error;
1071 }
1072
1073 /* Zero could be a valid value for a handle so flag it to -1. */
1074 stream->handle = -1;
1075
1076error:
1077 return stream;
1078}
1079
8b366481
DG
1080/*
1081 * Alloc new UST app event.
1082 */
1083static
1084struct ust_app_event *alloc_ust_app_event(char *name,
1085 struct lttng_ust_event *attr)
1086{
1087 struct ust_app_event *ua_event;
1088
1089 /* Init most of the default value by allocating and zeroing */
1090 ua_event = zmalloc(sizeof(struct ust_app_event));
1091 if (ua_event == NULL) {
1092 PERROR("malloc");
1093 goto error;
1094 }
1095
1096 ua_event->enabled = 1;
1097 strncpy(ua_event->name, name, sizeof(ua_event->name));
1098 ua_event->name[sizeof(ua_event->name) - 1] = '\0';
bec39940 1099 lttng_ht_node_init_str(&ua_event->node, ua_event->name);
8b366481
DG
1100
1101 /* Copy attributes */
1102 if (attr) {
1103 memcpy(&ua_event->attr, attr, sizeof(ua_event->attr));
1104 }
1105
1106 DBG3("UST app event %s allocated", ua_event->name);
1107
1108 return ua_event;
1109
1110error:
1111 return NULL;
1112}
1113
1114/*
1115 * Alloc new UST app context.
1116 */
1117static
bdf64013 1118struct ust_app_ctx *alloc_ust_app_ctx(struct lttng_ust_context_attr *uctx)
8b366481
DG
1119{
1120 struct ust_app_ctx *ua_ctx;
1121
1122 ua_ctx = zmalloc(sizeof(struct ust_app_ctx));
1123 if (ua_ctx == NULL) {
1124 goto error;
1125 }
1126
31746f93
DG
1127 CDS_INIT_LIST_HEAD(&ua_ctx->list);
1128
8b366481
DG
1129 if (uctx) {
1130 memcpy(&ua_ctx->ctx, uctx, sizeof(ua_ctx->ctx));
bdf64013
JG
1131 if (uctx->ctx == LTTNG_UST_CONTEXT_APP_CONTEXT) {
1132 char *provider_name = NULL, *ctx_name = NULL;
1133
1134 provider_name = strdup(uctx->u.app_ctx.provider_name);
1135 ctx_name = strdup(uctx->u.app_ctx.ctx_name);
1136 if (!provider_name || !ctx_name) {
1137 free(provider_name);
1138 free(ctx_name);
1139 goto error;
1140 }
1141
1142 ua_ctx->ctx.u.app_ctx.provider_name = provider_name;
1143 ua_ctx->ctx.u.app_ctx.ctx_name = ctx_name;
1144 }
8b366481
DG
1145 }
1146
1147 DBG3("UST app context %d allocated", ua_ctx->ctx.ctx);
8b366481 1148 return ua_ctx;
bdf64013
JG
1149error:
1150 free(ua_ctx);
1151 return NULL;
8b366481
DG
1152}
1153
025faf73
DG
1154/*
1155 * Allocate a filter and copy the given original filter.
1156 *
1157 * Return allocated filter or NULL on error.
1158 */
51755dc8
JG
1159static struct lttng_filter_bytecode *copy_filter_bytecode(
1160 struct lttng_filter_bytecode *orig_f)
025faf73 1161{
51755dc8 1162 struct lttng_filter_bytecode *filter = NULL;
025faf73
DG
1163
1164 /* Copy filter bytecode */
1165 filter = zmalloc(sizeof(*filter) + orig_f->len);
1166 if (!filter) {
51755dc8 1167 PERROR("zmalloc alloc filter bytecode");
025faf73
DG
1168 goto error;
1169 }
1170
1171 memcpy(filter, orig_f, sizeof(*filter) + orig_f->len);
1172
1173error:
1174 return filter;
1175}
1176
51755dc8
JG
1177/*
1178 * Create a liblttng-ust filter bytecode from given bytecode.
1179 *
1180 * Return allocated filter or NULL on error.
1181 */
1182static struct lttng_ust_filter_bytecode *create_ust_bytecode_from_bytecode(
1183 struct lttng_filter_bytecode *orig_f)
1184{
1185 struct lttng_ust_filter_bytecode *filter = NULL;
1186
1187 /* Copy filter bytecode */
1188 filter = zmalloc(sizeof(*filter) + orig_f->len);
1189 if (!filter) {
1190 PERROR("zmalloc alloc ust filter bytecode");
1191 goto error;
1192 }
1193
1194 assert(sizeof(struct lttng_filter_bytecode) ==
1195 sizeof(struct lttng_ust_filter_bytecode));
1196 memcpy(filter, orig_f, sizeof(*filter) + orig_f->len);
1197error:
1198 return filter;
1199}
1200
099e26bd 1201/*
421cb601
DG
1202 * Find an ust_app using the sock and return it. RCU read side lock must be
1203 * held before calling this helper function.
099e26bd 1204 */
f20baf8e 1205struct ust_app *ust_app_find_by_sock(int sock)
099e26bd 1206{
bec39940 1207 struct lttng_ht_node_ulong *node;
bec39940 1208 struct lttng_ht_iter iter;
f6a9efaa 1209
852d0037 1210 lttng_ht_lookup(ust_app_ht_by_sock, (void *)((unsigned long) sock), &iter);
bec39940 1211 node = lttng_ht_iter_get_node_ulong(&iter);
f6a9efaa
DG
1212 if (node == NULL) {
1213 DBG2("UST app find by sock %d not found", sock);
f6a9efaa
DG
1214 goto error;
1215 }
852d0037
DG
1216
1217 return caa_container_of(node, struct ust_app, sock_n);
f6a9efaa
DG
1218
1219error:
1220 return NULL;
099e26bd
DG
1221}
1222
d0b96690
DG
1223/*
1224 * Find an ust_app using the notify sock and return it. RCU read side lock must
1225 * be held before calling this helper function.
1226 */
1227static struct ust_app *find_app_by_notify_sock(int sock)
1228{
1229 struct lttng_ht_node_ulong *node;
1230 struct lttng_ht_iter iter;
1231
1232 lttng_ht_lookup(ust_app_ht_by_notify_sock, (void *)((unsigned long) sock),
1233 &iter);
1234 node = lttng_ht_iter_get_node_ulong(&iter);
1235 if (node == NULL) {
1236 DBG2("UST app find by notify sock %d not found", sock);
1237 goto error;
1238 }
1239
1240 return caa_container_of(node, struct ust_app, notify_sock_n);
1241
1242error:
1243 return NULL;
1244}
1245
025faf73
DG
1246/*
1247 * Lookup for an ust app event based on event name, filter bytecode and the
1248 * event loglevel.
1249 *
1250 * Return an ust_app_event object or NULL on error.
1251 */
18eace3b 1252static struct ust_app_event *find_ust_app_event(struct lttng_ht *ht,
2106efa0
PP
1253 char *name, struct lttng_filter_bytecode *filter,
1254 int loglevel_value,
39c5a3a7 1255 const struct lttng_event_exclusion *exclusion)
18eace3b
DG
1256{
1257 struct lttng_ht_iter iter;
1258 struct lttng_ht_node_str *node;
1259 struct ust_app_event *event = NULL;
1260 struct ust_app_ht_key key;
18eace3b
DG
1261
1262 assert(name);
1263 assert(ht);
1264
1265 /* Setup key for event lookup. */
1266 key.name = name;
1267 key.filter = filter;
2106efa0 1268 key.loglevel_type = loglevel_value;
39c5a3a7 1269 /* lttng_event_exclusion and lttng_ust_event_exclusion structures are similar */
51755dc8 1270 key.exclusion = exclusion;
18eace3b 1271
025faf73
DG
1272 /* Lookup using the event name as hash and a custom match fct. */
1273 cds_lfht_lookup(ht->ht, ht->hash_fct((void *) name, lttng_ht_seed),
1274 ht_match_ust_app_event, &key, &iter.iter);
18eace3b
DG
1275 node = lttng_ht_iter_get_node_str(&iter);
1276 if (node == NULL) {
1277 goto end;
1278 }
1279
1280 event = caa_container_of(node, struct ust_app_event, node);
1281
1282end:
18eace3b
DG
1283 return event;
1284}
1285
55cc08a6
DG
1286/*
1287 * Create the channel context on the tracer.
d0b96690
DG
1288 *
1289 * Called with UST app session lock held.
55cc08a6
DG
1290 */
1291static
1292int create_ust_channel_context(struct ust_app_channel *ua_chan,
1293 struct ust_app_ctx *ua_ctx, struct ust_app *app)
1294{
1295 int ret;
1296
840cb59c 1297 health_code_update();
86acf0da 1298
fb45065e 1299 pthread_mutex_lock(&app->sock_lock);
852d0037 1300 ret = ustctl_add_context(app->sock, &ua_ctx->ctx,
55cc08a6 1301 ua_chan->obj, &ua_ctx->obj);
fb45065e 1302 pthread_mutex_unlock(&app->sock_lock);
55cc08a6 1303 if (ret < 0) {
ffe60014
DG
1304 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1305 ERR("UST app create channel context failed for app (pid: %d) "
1306 "with ret %d", app->pid, ret);
1307 } else {
3757b385
DG
1308 /*
1309 * This is normal behavior, an application can die during the
1310 * creation process. Don't report an error so the execution can
1311 * continue normally.
1312 */
1313 ret = 0;
ffe60014
DG
1314 DBG3("UST app disable event failed. Application is dead.");
1315 }
55cc08a6
DG
1316 goto error;
1317 }
1318
1319 ua_ctx->handle = ua_ctx->obj->handle;
1320
d0b96690
DG
1321 DBG2("UST app context handle %d created successfully for channel %s",
1322 ua_ctx->handle, ua_chan->name);
55cc08a6
DG
1323
1324error:
840cb59c 1325 health_code_update();
55cc08a6
DG
1326 return ret;
1327}
1328
53a80697
MD
1329/*
1330 * Set the filter on the tracer.
1331 */
1332static
1333int set_ust_event_filter(struct ust_app_event *ua_event,
1334 struct ust_app *app)
1335{
1336 int ret;
51755dc8 1337 struct lttng_ust_filter_bytecode *ust_bytecode = NULL;
53a80697 1338
840cb59c 1339 health_code_update();
86acf0da 1340
53a80697 1341 if (!ua_event->filter) {
86acf0da
DG
1342 ret = 0;
1343 goto error;
53a80697
MD
1344 }
1345
51755dc8
JG
1346 ust_bytecode = create_ust_bytecode_from_bytecode(ua_event->filter);
1347 if (!ust_bytecode) {
1348 ret = -LTTNG_ERR_NOMEM;
1349 goto error;
1350 }
fb45065e 1351 pthread_mutex_lock(&app->sock_lock);
51755dc8 1352 ret = ustctl_set_filter(app->sock, ust_bytecode,
53a80697 1353 ua_event->obj);
fb45065e 1354 pthread_mutex_unlock(&app->sock_lock);
53a80697 1355 if (ret < 0) {
ffe60014
DG
1356 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1357 ERR("UST app event %s filter failed for app (pid: %d) "
1358 "with ret %d", ua_event->attr.name, app->pid, ret);
1359 } else {
3757b385
DG
1360 /*
1361 * This is normal behavior, an application can die during the
1362 * creation process. Don't report an error so the execution can
1363 * continue normally.
1364 */
1365 ret = 0;
ffe60014
DG
1366 DBG3("UST app filter event failed. Application is dead.");
1367 }
53a80697
MD
1368 goto error;
1369 }
1370
1371 DBG2("UST filter set successfully for event %s", ua_event->name);
1372
1373error:
840cb59c 1374 health_code_update();
51755dc8 1375 free(ust_bytecode);
53a80697
MD
1376 return ret;
1377}
1378
51755dc8
JG
1379static
1380struct lttng_ust_event_exclusion *create_ust_exclusion_from_exclusion(
1381 struct lttng_event_exclusion *exclusion)
1382{
1383 struct lttng_ust_event_exclusion *ust_exclusion = NULL;
1384 size_t exclusion_alloc_size = sizeof(struct lttng_ust_event_exclusion) +
1385 LTTNG_UST_SYM_NAME_LEN * exclusion->count;
1386
1387 ust_exclusion = zmalloc(exclusion_alloc_size);
1388 if (!ust_exclusion) {
1389 PERROR("malloc");
1390 goto end;
1391 }
1392
1393 assert(sizeof(struct lttng_event_exclusion) ==
1394 sizeof(struct lttng_ust_event_exclusion));
1395 memcpy(ust_exclusion, exclusion, exclusion_alloc_size);
1396end:
1397 return ust_exclusion;
1398}
1399
7cc9a73c
JI
1400/*
1401 * Set event exclusions on the tracer.
1402 */
1403static
1404int set_ust_event_exclusion(struct ust_app_event *ua_event,
1405 struct ust_app *app)
1406{
1407 int ret;
51755dc8 1408 struct lttng_ust_event_exclusion *ust_exclusion = NULL;
7cc9a73c
JI
1409
1410 health_code_update();
1411
1412 if (!ua_event->exclusion || !ua_event->exclusion->count) {
1413 ret = 0;
1414 goto error;
1415 }
1416
51755dc8
JG
1417 ust_exclusion = create_ust_exclusion_from_exclusion(
1418 ua_event->exclusion);
1419 if (!ust_exclusion) {
1420 ret = -LTTNG_ERR_NOMEM;
1421 goto error;
1422 }
fb45065e 1423 pthread_mutex_lock(&app->sock_lock);
51755dc8 1424 ret = ustctl_set_exclusion(app->sock, ust_exclusion, ua_event->obj);
fb45065e 1425 pthread_mutex_unlock(&app->sock_lock);
7cc9a73c
JI
1426 if (ret < 0) {
1427 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1428 ERR("UST app event %s exclusions failed for app (pid: %d) "
1429 "with ret %d", ua_event->attr.name, app->pid, ret);
1430 } else {
1431 /*
1432 * This is normal behavior, an application can die during the
1433 * creation process. Don't report an error so the execution can
1434 * continue normally.
1435 */
1436 ret = 0;
1437 DBG3("UST app event exclusion failed. Application is dead.");
1438 }
1439 goto error;
1440 }
1441
1442 DBG2("UST exclusion set successfully for event %s", ua_event->name);
1443
1444error:
1445 health_code_update();
51755dc8 1446 free(ust_exclusion);
7cc9a73c
JI
1447 return ret;
1448}
1449
9730260e
DG
1450/*
1451 * Disable the specified event on to UST tracer for the UST session.
1452 */
1453static int disable_ust_event(struct ust_app *app,
1454 struct ust_app_session *ua_sess, struct ust_app_event *ua_event)
1455{
1456 int ret;
1457
840cb59c 1458 health_code_update();
86acf0da 1459
fb45065e 1460 pthread_mutex_lock(&app->sock_lock);
852d0037 1461 ret = ustctl_disable(app->sock, ua_event->obj);
fb45065e 1462 pthread_mutex_unlock(&app->sock_lock);
9730260e 1463 if (ret < 0) {
ffe60014
DG
1464 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1465 ERR("UST app event %s disable failed for app (pid: %d) "
1466 "and session handle %d with ret %d",
1467 ua_event->attr.name, app->pid, ua_sess->handle, ret);
1468 } else {
3757b385
DG
1469 /*
1470 * This is normal behavior, an application can die during the
1471 * creation process. Don't report an error so the execution can
1472 * continue normally.
1473 */
1474 ret = 0;
ffe60014
DG
1475 DBG3("UST app disable event failed. Application is dead.");
1476 }
9730260e
DG
1477 goto error;
1478 }
1479
1480 DBG2("UST app event %s disabled successfully for app (pid: %d)",
852d0037 1481 ua_event->attr.name, app->pid);
9730260e
DG
1482
1483error:
840cb59c 1484 health_code_update();
9730260e
DG
1485 return ret;
1486}
1487
78f0bacd
DG
1488/*
1489 * Disable the specified channel on to UST tracer for the UST session.
1490 */
1491static int disable_ust_channel(struct ust_app *app,
1492 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
1493{
1494 int ret;
1495
840cb59c 1496 health_code_update();
86acf0da 1497
fb45065e 1498 pthread_mutex_lock(&app->sock_lock);
852d0037 1499 ret = ustctl_disable(app->sock, ua_chan->obj);
fb45065e 1500 pthread_mutex_unlock(&app->sock_lock);
78f0bacd 1501 if (ret < 0) {
ffe60014
DG
1502 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1503 ERR("UST app channel %s disable failed for app (pid: %d) "
1504 "and session handle %d with ret %d",
1505 ua_chan->name, app->pid, ua_sess->handle, ret);
1506 } else {
3757b385
DG
1507 /*
1508 * This is normal behavior, an application can die during the
1509 * creation process. Don't report an error so the execution can
1510 * continue normally.
1511 */
1512 ret = 0;
ffe60014
DG
1513 DBG3("UST app disable channel failed. Application is dead.");
1514 }
78f0bacd
DG
1515 goto error;
1516 }
1517
78f0bacd 1518 DBG2("UST app channel %s disabled successfully for app (pid: %d)",
852d0037 1519 ua_chan->name, app->pid);
78f0bacd
DG
1520
1521error:
840cb59c 1522 health_code_update();
78f0bacd
DG
1523 return ret;
1524}
1525
1526/*
1527 * Enable the specified channel on to UST tracer for the UST session.
1528 */
1529static int enable_ust_channel(struct ust_app *app,
1530 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
1531{
1532 int ret;
1533
840cb59c 1534 health_code_update();
86acf0da 1535
fb45065e 1536 pthread_mutex_lock(&app->sock_lock);
852d0037 1537 ret = ustctl_enable(app->sock, ua_chan->obj);
fb45065e 1538 pthread_mutex_unlock(&app->sock_lock);
78f0bacd 1539 if (ret < 0) {
ffe60014
DG
1540 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1541 ERR("UST app channel %s enable failed for app (pid: %d) "
1542 "and session handle %d with ret %d",
1543 ua_chan->name, app->pid, ua_sess->handle, ret);
1544 } else {
3757b385
DG
1545 /*
1546 * This is normal behavior, an application can die during the
1547 * creation process. Don't report an error so the execution can
1548 * continue normally.
1549 */
1550 ret = 0;
ffe60014
DG
1551 DBG3("UST app enable channel failed. Application is dead.");
1552 }
78f0bacd
DG
1553 goto error;
1554 }
1555
1556 ua_chan->enabled = 1;
1557
1558 DBG2("UST app channel %s enabled successfully for app (pid: %d)",
852d0037 1559 ua_chan->name, app->pid);
78f0bacd
DG
1560
1561error:
840cb59c 1562 health_code_update();
78f0bacd
DG
1563 return ret;
1564}
1565
edb67388
DG
1566/*
1567 * Enable the specified event on to UST tracer for the UST session.
1568 */
1569static int enable_ust_event(struct ust_app *app,
1570 struct ust_app_session *ua_sess, struct ust_app_event *ua_event)
1571{
1572 int ret;
1573
840cb59c 1574 health_code_update();
86acf0da 1575
fb45065e 1576 pthread_mutex_lock(&app->sock_lock);
852d0037 1577 ret = ustctl_enable(app->sock, ua_event->obj);
fb45065e 1578 pthread_mutex_unlock(&app->sock_lock);
edb67388 1579 if (ret < 0) {
ffe60014
DG
1580 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1581 ERR("UST app event %s enable failed for app (pid: %d) "
1582 "and session handle %d with ret %d",
1583 ua_event->attr.name, app->pid, ua_sess->handle, ret);
1584 } else {
3757b385
DG
1585 /*
1586 * This is normal behavior, an application can die during the
1587 * creation process. Don't report an error so the execution can
1588 * continue normally.
1589 */
1590 ret = 0;
ffe60014
DG
1591 DBG3("UST app enable event failed. Application is dead.");
1592 }
edb67388
DG
1593 goto error;
1594 }
1595
1596 DBG2("UST app event %s enabled successfully for app (pid: %d)",
852d0037 1597 ua_event->attr.name, app->pid);
edb67388
DG
1598
1599error:
840cb59c 1600 health_code_update();
edb67388
DG
1601 return ret;
1602}
1603
099e26bd 1604/*
7972aab2 1605 * Send channel and stream buffer to application.
4f3ab6ee 1606 *
ffe60014 1607 * Return 0 on success. On error, a negative value is returned.
4f3ab6ee 1608 */
7972aab2
DG
1609static int send_channel_pid_to_ust(struct ust_app *app,
1610 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
4f3ab6ee
DG
1611{
1612 int ret;
ffe60014 1613 struct ust_app_stream *stream, *stmp;
4f3ab6ee
DG
1614
1615 assert(app);
ffe60014 1616 assert(ua_sess);
4f3ab6ee 1617 assert(ua_chan);
4f3ab6ee 1618
840cb59c 1619 health_code_update();
4f3ab6ee 1620
7972aab2
DG
1621 DBG("UST app sending channel %s to UST app sock %d", ua_chan->name,
1622 app->sock);
86acf0da 1623
ffe60014
DG
1624 /* Send channel to the application. */
1625 ret = ust_consumer_send_channel_to_ust(app, ua_sess, ua_chan);
a7169585
MD
1626 if (ret == -EPIPE || ret == -LTTNG_UST_ERR_EXITING) {
1627 ret = -ENOTCONN; /* Caused by app exiting. */
1628 goto error;
1629 } else if (ret < 0) {
b551a063
DG
1630 goto error;
1631 }
1632
d88aee68
DG
1633 health_code_update();
1634
ffe60014
DG
1635 /* Send all streams to application. */
1636 cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
1637 ret = ust_consumer_send_stream_to_ust(app, ua_chan, stream);
a7169585
MD
1638 if (ret == -EPIPE || ret == -LTTNG_UST_ERR_EXITING) {
1639 ret = -ENOTCONN; /* Caused by app exiting. */
1640 goto error;
1641 } else if (ret < 0) {
ffe60014
DG
1642 goto error;
1643 }
1644 /* We don't need the stream anymore once sent to the tracer. */
1645 cds_list_del(&stream->list);
fb45065e 1646 delete_ust_app_stream(-1, stream, app);
ffe60014 1647 }
ffe60014
DG
1648 /* Flag the channel that it is sent to the application. */
1649 ua_chan->is_sent = 1;
ffe60014 1650
b551a063 1651error:
840cb59c 1652 health_code_update();
b551a063
DG
1653 return ret;
1654}
1655
91d76f53 1656/*
5b4a0ec0 1657 * Create the specified event onto the UST tracer for a UST session.
d0b96690
DG
1658 *
1659 * Should be called with session mutex held.
91d76f53 1660 */
edb67388
DG
1661static
1662int create_ust_event(struct ust_app *app, struct ust_app_session *ua_sess,
1663 struct ust_app_channel *ua_chan, struct ust_app_event *ua_event)
91d76f53 1664{
5b4a0ec0 1665 int ret = 0;
284d8f55 1666
840cb59c 1667 health_code_update();
86acf0da 1668
5b4a0ec0 1669 /* Create UST event on tracer */
fb45065e 1670 pthread_mutex_lock(&app->sock_lock);
852d0037 1671 ret = ustctl_create_event(app->sock, &ua_event->attr, ua_chan->obj,
5b4a0ec0 1672 &ua_event->obj);
fb45065e 1673 pthread_mutex_unlock(&app->sock_lock);
5b4a0ec0 1674 if (ret < 0) {
ffe60014
DG
1675 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1676 ERR("Error ustctl create event %s for app pid: %d with ret %d",
1677 ua_event->attr.name, app->pid, ret);
1678 } else {
3757b385
DG
1679 /*
1680 * This is normal behavior, an application can die during the
1681 * creation process. Don't report an error so the execution can
1682 * continue normally.
1683 */
1684 ret = 0;
ffe60014
DG
1685 DBG3("UST app create event failed. Application is dead.");
1686 }
5b4a0ec0 1687 goto error;
91d76f53 1688 }
f6a9efaa 1689
5b4a0ec0 1690 ua_event->handle = ua_event->obj->handle;
284d8f55 1691
5b4a0ec0 1692 DBG2("UST app event %s created successfully for pid:%d",
852d0037 1693 ua_event->attr.name, app->pid);
f6a9efaa 1694
840cb59c 1695 health_code_update();
86acf0da 1696
025faf73
DG
1697 /* Set filter if one is present. */
1698 if (ua_event->filter) {
1699 ret = set_ust_event_filter(ua_event, app);
1700 if (ret < 0) {
1701 goto error;
1702 }
1703 }
1704
7cc9a73c
JI
1705 /* Set exclusions for the event */
1706 if (ua_event->exclusion) {
1707 ret = set_ust_event_exclusion(ua_event, app);
1708 if (ret < 0) {
1709 goto error;
1710 }
1711 }
1712
8535a6d9 1713 /* If event not enabled, disable it on the tracer */
40113787
MD
1714 if (ua_event->enabled) {
1715 /*
1716 * We now need to explicitly enable the event, since it
1717 * is now disabled at creation.
1718 */
1719 ret = enable_ust_event(app, ua_sess, ua_event);
1720 if (ret < 0) {
1721 /*
1722 * If we hit an EPERM, something is wrong with our enable call. If
1723 * we get an EEXIST, there is a problem on the tracer side since we
1724 * just created it.
1725 */
1726 switch (ret) {
1727 case -LTTNG_UST_ERR_PERM:
1728 /* Code flow problem */
1729 assert(0);
1730 case -LTTNG_UST_ERR_EXIST:
1731 /* It's OK for our use case. */
1732 ret = 0;
1733 break;
1734 default:
1735 break;
1736 }
1737 goto error;
1738 }
8535a6d9
DG
1739 }
1740
5b4a0ec0 1741error:
840cb59c 1742 health_code_update();
5b4a0ec0 1743 return ret;
91d76f53 1744}
48842b30 1745
5b4a0ec0
DG
1746/*
1747 * Copy data between an UST app event and a LTT event.
1748 */
421cb601 1749static void shadow_copy_event(struct ust_app_event *ua_event,
48842b30
DG
1750 struct ltt_ust_event *uevent)
1751{
b4ffad32
JI
1752 size_t exclusion_alloc_size;
1753
48842b30
DG
1754 strncpy(ua_event->name, uevent->attr.name, sizeof(ua_event->name));
1755 ua_event->name[sizeof(ua_event->name) - 1] = '\0';
1756
fc34caaa
DG
1757 ua_event->enabled = uevent->enabled;
1758
5b4a0ec0
DG
1759 /* Copy event attributes */
1760 memcpy(&ua_event->attr, &uevent->attr, sizeof(ua_event->attr));
1761
53a80697
MD
1762 /* Copy filter bytecode */
1763 if (uevent->filter) {
51755dc8 1764 ua_event->filter = copy_filter_bytecode(uevent->filter);
025faf73 1765 /* Filter might be NULL here in case of ENONEM. */
53a80697 1766 }
b4ffad32
JI
1767
1768 /* Copy exclusion data */
1769 if (uevent->exclusion) {
51755dc8 1770 exclusion_alloc_size = sizeof(struct lttng_event_exclusion) +
b4ffad32
JI
1771 LTTNG_UST_SYM_NAME_LEN * uevent->exclusion->count;
1772 ua_event->exclusion = zmalloc(exclusion_alloc_size);
5f8df26c
JI
1773 if (ua_event->exclusion == NULL) {
1774 PERROR("malloc");
1775 } else {
1776 memcpy(ua_event->exclusion, uevent->exclusion,
1777 exclusion_alloc_size);
b4ffad32
JI
1778 }
1779 }
48842b30
DG
1780}
1781
5b4a0ec0
DG
1782/*
1783 * Copy data between an UST app channel and a LTT channel.
1784 */
421cb601 1785static void shadow_copy_channel(struct ust_app_channel *ua_chan,
48842b30
DG
1786 struct ltt_ust_channel *uchan)
1787{
bec39940 1788 struct lttng_ht_iter iter;
48842b30 1789 struct ltt_ust_event *uevent;
55cc08a6 1790 struct ltt_ust_context *uctx;
48842b30
DG
1791 struct ust_app_event *ua_event;
1792
fc34caaa 1793 DBG2("UST app shadow copy of channel %s started", ua_chan->name);
48842b30
DG
1794
1795 strncpy(ua_chan->name, uchan->name, sizeof(ua_chan->name));
1796 ua_chan->name[sizeof(ua_chan->name) - 1] = '\0';
ffe60014 1797
1624d5b7
JD
1798 ua_chan->tracefile_size = uchan->tracefile_size;
1799 ua_chan->tracefile_count = uchan->tracefile_count;
1800
ffe60014
DG
1801 /* Copy event attributes since the layout is different. */
1802 ua_chan->attr.subbuf_size = uchan->attr.subbuf_size;
1803 ua_chan->attr.num_subbuf = uchan->attr.num_subbuf;
1804 ua_chan->attr.overwrite = uchan->attr.overwrite;
1805 ua_chan->attr.switch_timer_interval = uchan->attr.switch_timer_interval;
1806 ua_chan->attr.read_timer_interval = uchan->attr.read_timer_interval;
e9404c27 1807 ua_chan->monitor_timer_interval = uchan->monitor_timer_interval;
ffe60014 1808 ua_chan->attr.output = uchan->attr.output;
491d1539
MD
1809 ua_chan->attr.blocking_timeout = uchan->attr.u.s.blocking_timeout;
1810
ffe60014
DG
1811 /*
1812 * Note that the attribute channel type is not set since the channel on the
1813 * tracing registry side does not have this information.
1814 */
48842b30 1815
fc34caaa 1816 ua_chan->enabled = uchan->enabled;
7972aab2 1817 ua_chan->tracing_channel_id = uchan->id;
fc34caaa 1818
31746f93 1819 cds_list_for_each_entry(uctx, &uchan->ctx_list, list) {
bdf64013
JG
1820 struct ust_app_ctx *ua_ctx = alloc_ust_app_ctx(&uctx->ctx);
1821
55cc08a6
DG
1822 if (ua_ctx == NULL) {
1823 continue;
1824 }
bec39940
DG
1825 lttng_ht_node_init_ulong(&ua_ctx->node,
1826 (unsigned long) ua_ctx->ctx.ctx);
aa3514e9 1827 lttng_ht_add_ulong(ua_chan->ctx, &ua_ctx->node);
31746f93 1828 cds_list_add_tail(&ua_ctx->list, &ua_chan->ctx_list);
55cc08a6 1829 }
48842b30 1830
421cb601 1831 /* Copy all events from ltt ust channel to ust app channel */
bec39940 1832 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
18eace3b 1833 ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name,
39c5a3a7 1834 uevent->filter, uevent->attr.loglevel, uevent->exclusion);
18eace3b 1835 if (ua_event == NULL) {
421cb601 1836 DBG2("UST event %s not found on shadow copy channel",
48842b30 1837 uevent->attr.name);
284d8f55 1838 ua_event = alloc_ust_app_event(uevent->attr.name, &uevent->attr);
48842b30 1839 if (ua_event == NULL) {
5b4a0ec0 1840 continue;
48842b30 1841 }
421cb601 1842 shadow_copy_event(ua_event, uevent);
d0b96690 1843 add_unique_ust_app_event(ua_chan, ua_event);
48842b30 1844 }
48842b30
DG
1845 }
1846
fc34caaa 1847 DBG3("UST app shadow copy of channel %s done", ua_chan->name);
48842b30
DG
1848}
1849
5b4a0ec0
DG
1850/*
1851 * Copy data between a UST app session and a regular LTT session.
1852 */
421cb601 1853static void shadow_copy_session(struct ust_app_session *ua_sess,
bec39940 1854 struct ltt_ust_session *usess, struct ust_app *app)
48842b30 1855{
bec39940
DG
1856 struct lttng_ht_node_str *ua_chan_node;
1857 struct lttng_ht_iter iter;
48842b30
DG
1858 struct ltt_ust_channel *uchan;
1859 struct ust_app_channel *ua_chan;
477d7741
MD
1860 time_t rawtime;
1861 struct tm *timeinfo;
1862 char datetime[16];
1863 int ret;
d7ba1388 1864 char tmp_shm_path[PATH_MAX];
477d7741
MD
1865
1866 /* Get date and time for unique app path */
1867 time(&rawtime);
1868 timeinfo = localtime(&rawtime);
1869 strftime(datetime, sizeof(datetime), "%Y%m%d-%H%M%S", timeinfo);
48842b30 1870
421cb601 1871 DBG2("Shadow copy of session handle %d", ua_sess->handle);
48842b30 1872
7972aab2
DG
1873 ua_sess->tracing_id = usess->id;
1874 ua_sess->id = get_next_session_id();
1875 ua_sess->uid = app->uid;
1876 ua_sess->gid = app->gid;
1877 ua_sess->euid = usess->uid;
1878 ua_sess->egid = usess->gid;
1879 ua_sess->buffer_type = usess->buffer_type;
1880 ua_sess->bits_per_long = app->bits_per_long;
6addfa37 1881
7972aab2 1882 /* There is only one consumer object per session possible. */
6addfa37 1883 consumer_output_get(usess->consumer);
7972aab2 1884 ua_sess->consumer = usess->consumer;
6addfa37 1885
2bba9e53 1886 ua_sess->output_traces = usess->output_traces;
ecc48a90 1887 ua_sess->live_timer_interval = usess->live_timer_interval;
84ad93e8
DG
1888 copy_channel_attr_to_ustctl(&ua_sess->metadata_attr,
1889 &usess->metadata_attr);
7972aab2
DG
1890
1891 switch (ua_sess->buffer_type) {
1892 case LTTNG_BUFFER_PER_PID:
1893 ret = snprintf(ua_sess->path, sizeof(ua_sess->path),
dec56f6c 1894 DEFAULT_UST_TRACE_PID_PATH "/%s-%d-%s", app->name, app->pid,
7972aab2
DG
1895 datetime);
1896 break;
1897 case LTTNG_BUFFER_PER_UID:
1898 ret = snprintf(ua_sess->path, sizeof(ua_sess->path),
1899 DEFAULT_UST_TRACE_UID_PATH, ua_sess->uid, app->bits_per_long);
1900 break;
1901 default:
1902 assert(0);
1903 goto error;
1904 }
477d7741
MD
1905 if (ret < 0) {
1906 PERROR("asprintf UST shadow copy session");
477d7741 1907 assert(0);
7972aab2 1908 goto error;
477d7741
MD
1909 }
1910
3d071855
MD
1911 strncpy(ua_sess->root_shm_path, usess->root_shm_path,
1912 sizeof(ua_sess->root_shm_path));
1913 ua_sess->root_shm_path[sizeof(ua_sess->root_shm_path) - 1] = '\0';
d7ba1388
MD
1914 strncpy(ua_sess->shm_path, usess->shm_path,
1915 sizeof(ua_sess->shm_path));
1916 ua_sess->shm_path[sizeof(ua_sess->shm_path) - 1] = '\0';
1917 if (ua_sess->shm_path[0]) {
1918 switch (ua_sess->buffer_type) {
1919 case LTTNG_BUFFER_PER_PID:
1920 ret = snprintf(tmp_shm_path, sizeof(tmp_shm_path),
1921 DEFAULT_UST_TRACE_PID_PATH "/%s-%d-%s",
1922 app->name, app->pid, datetime);
1923 break;
1924 case LTTNG_BUFFER_PER_UID:
1925 ret = snprintf(tmp_shm_path, sizeof(tmp_shm_path),
1926 DEFAULT_UST_TRACE_UID_PATH,
1927 app->uid, app->bits_per_long);
1928 break;
1929 default:
1930 assert(0);
1931 goto error;
1932 }
1933 if (ret < 0) {
1934 PERROR("sprintf UST shadow copy session");
1935 assert(0);
1936 goto error;
1937 }
1938 strncat(ua_sess->shm_path, tmp_shm_path,
1939 sizeof(ua_sess->shm_path) - strlen(ua_sess->shm_path) - 1);
1940 ua_sess->shm_path[sizeof(ua_sess->shm_path) - 1] = '\0';
1941 }
1942
48842b30 1943 /* Iterate over all channels in global domain. */
bec39940
DG
1944 cds_lfht_for_each_entry(usess->domain_global.channels->ht, &iter.iter,
1945 uchan, node.node) {
1946 struct lttng_ht_iter uiter;
ba767faf 1947
bec39940
DG
1948 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
1949 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
5b4a0ec0 1950 if (ua_chan_node != NULL) {
fc34caaa 1951 /* Session exist. Contiuing. */
5b4a0ec0
DG
1952 continue;
1953 }
421cb601 1954
5b4a0ec0
DG
1955 DBG2("Channel %s not found on shadow session copy, creating it",
1956 uchan->name);
fb83fe64
JD
1957 ua_chan = alloc_ust_app_channel(uchan->name, ua_sess,
1958 &uchan->attr);
5b4a0ec0 1959 if (ua_chan == NULL) {
fc34caaa 1960 /* malloc failed FIXME: Might want to do handle ENOMEM .. */
5b4a0ec0 1961 continue;
48842b30 1962 }
5b4a0ec0 1963 shadow_copy_channel(ua_chan, uchan);
ffe60014
DG
1964 /*
1965 * The concept of metadata channel does not exist on the tracing
1966 * registry side of the session daemon so this can only be a per CPU
1967 * channel and not metadata.
1968 */
1969 ua_chan->attr.type = LTTNG_UST_CHAN_PER_CPU;
1970
bec39940 1971 lttng_ht_add_unique_str(ua_sess->channels, &ua_chan->node);
48842b30 1972 }
6addfa37 1973 return;
7972aab2
DG
1974
1975error:
6addfa37 1976 consumer_output_put(ua_sess->consumer);
48842b30
DG
1977}
1978
78f0bacd
DG
1979/*
1980 * Lookup sesison wrapper.
1981 */
84cd17c6
MD
1982static
1983void __lookup_session_by_app(struct ltt_ust_session *usess,
bec39940 1984 struct ust_app *app, struct lttng_ht_iter *iter)
84cd17c6
MD
1985{
1986 /* Get right UST app session from app */
d9bf3ca4 1987 lttng_ht_lookup(app->sessions, &usess->id, iter);
84cd17c6
MD
1988}
1989
421cb601
DG
1990/*
1991 * Return ust app session from the app session hashtable using the UST session
a991f516 1992 * id.
421cb601 1993 */
48842b30
DG
1994static struct ust_app_session *lookup_session_by_app(
1995 struct ltt_ust_session *usess, struct ust_app *app)
1996{
bec39940 1997 struct lttng_ht_iter iter;
d9bf3ca4 1998 struct lttng_ht_node_u64 *node;
48842b30 1999
84cd17c6 2000 __lookup_session_by_app(usess, app, &iter);
d9bf3ca4 2001 node = lttng_ht_iter_get_node_u64(&iter);
48842b30
DG
2002 if (node == NULL) {
2003 goto error;
2004 }
2005
2006 return caa_container_of(node, struct ust_app_session, node);
2007
2008error:
2009 return NULL;
2010}
2011
7972aab2
DG
2012/*
2013 * Setup buffer registry per PID for the given session and application. If none
2014 * is found, a new one is created, added to the global registry and
2015 * initialized. If regp is valid, it's set with the newly created object.
2016 *
2017 * Return 0 on success or else a negative value.
2018 */
2019static int setup_buffer_reg_pid(struct ust_app_session *ua_sess,
2020 struct ust_app *app, struct buffer_reg_pid **regp)
2021{
2022 int ret = 0;
2023 struct buffer_reg_pid *reg_pid;
2024
2025 assert(ua_sess);
2026 assert(app);
2027
2028 rcu_read_lock();
2029
2030 reg_pid = buffer_reg_pid_find(ua_sess->id);
2031 if (!reg_pid) {
2032 /*
2033 * This is the create channel path meaning that if there is NO
2034 * registry available, we have to create one for this session.
2035 */
d7ba1388 2036 ret = buffer_reg_pid_create(ua_sess->id, &reg_pid,
3d071855 2037 ua_sess->root_shm_path, ua_sess->shm_path);
7972aab2
DG
2038 if (ret < 0) {
2039 goto error;
2040 }
7972aab2
DG
2041 } else {
2042 goto end;
2043 }
2044
2045 /* Initialize registry. */
2046 ret = ust_registry_session_init(&reg_pid->registry->reg.ust, app,
2047 app->bits_per_long, app->uint8_t_alignment,
2048 app->uint16_t_alignment, app->uint32_t_alignment,
af6142cf
MD
2049 app->uint64_t_alignment, app->long_alignment,
2050 app->byte_order, app->version.major,
3d071855
MD
2051 app->version.minor, reg_pid->root_shm_path,
2052 reg_pid->shm_path,
d7ba1388 2053 ua_sess->euid, ua_sess->egid);
7972aab2 2054 if (ret < 0) {
286c991a
MD
2055 /*
2056 * reg_pid->registry->reg.ust is NULL upon error, so we need to
2057 * destroy the buffer registry, because it is always expected
2058 * that if the buffer registry can be found, its ust registry is
2059 * non-NULL.
2060 */
2061 buffer_reg_pid_destroy(reg_pid);
7972aab2
DG
2062 goto error;
2063 }
2064
286c991a
MD
2065 buffer_reg_pid_add(reg_pid);
2066
7972aab2
DG
2067 DBG3("UST app buffer registry per PID created successfully");
2068
2069end:
2070 if (regp) {
2071 *regp = reg_pid;
2072 }
2073error:
2074 rcu_read_unlock();
2075 return ret;
2076}
2077
2078/*
2079 * Setup buffer registry per UID for the given session and application. If none
2080 * is found, a new one is created, added to the global registry and
2081 * initialized. If regp is valid, it's set with the newly created object.
2082 *
2083 * Return 0 on success or else a negative value.
2084 */
2085static int setup_buffer_reg_uid(struct ltt_ust_session *usess,
d7ba1388 2086 struct ust_app_session *ua_sess,
7972aab2
DG
2087 struct ust_app *app, struct buffer_reg_uid **regp)
2088{
2089 int ret = 0;
2090 struct buffer_reg_uid *reg_uid;
2091
2092 assert(usess);
2093 assert(app);
2094
2095 rcu_read_lock();
2096
2097 reg_uid = buffer_reg_uid_find(usess->id, app->bits_per_long, app->uid);
2098 if (!reg_uid) {
2099 /*
2100 * This is the create channel path meaning that if there is NO
2101 * registry available, we have to create one for this session.
2102 */
2103 ret = buffer_reg_uid_create(usess->id, app->bits_per_long, app->uid,
3d071855
MD
2104 LTTNG_DOMAIN_UST, &reg_uid,
2105 ua_sess->root_shm_path, ua_sess->shm_path);
7972aab2
DG
2106 if (ret < 0) {
2107 goto error;
2108 }
7972aab2
DG
2109 } else {
2110 goto end;
2111 }
2112
2113 /* Initialize registry. */
af6142cf 2114 ret = ust_registry_session_init(&reg_uid->registry->reg.ust, NULL,
7972aab2
DG
2115 app->bits_per_long, app->uint8_t_alignment,
2116 app->uint16_t_alignment, app->uint32_t_alignment,
af6142cf
MD
2117 app->uint64_t_alignment, app->long_alignment,
2118 app->byte_order, app->version.major,
3d071855
MD
2119 app->version.minor, reg_uid->root_shm_path,
2120 reg_uid->shm_path, usess->uid, usess->gid);
7972aab2 2121 if (ret < 0) {
286c991a
MD
2122 /*
2123 * reg_uid->registry->reg.ust is NULL upon error, so we need to
2124 * destroy the buffer registry, because it is always expected
2125 * that if the buffer registry can be found, its ust registry is
2126 * non-NULL.
2127 */
2128 buffer_reg_uid_destroy(reg_uid, NULL);
7972aab2
DG
2129 goto error;
2130 }
2131 /* Add node to teardown list of the session. */
2132 cds_list_add(&reg_uid->lnode, &usess->buffer_reg_uid_list);
2133
286c991a 2134 buffer_reg_uid_add(reg_uid);
7972aab2 2135
286c991a 2136 DBG3("UST app buffer registry per UID created successfully");
7972aab2
DG
2137end:
2138 if (regp) {
2139 *regp = reg_uid;
2140 }
2141error:
2142 rcu_read_unlock();
2143 return ret;
2144}
2145
421cb601 2146/*
3d8ca23b 2147 * Create a session on the tracer side for the given app.
421cb601 2148 *
3d8ca23b
DG
2149 * On success, ua_sess_ptr is populated with the session pointer or else left
2150 * untouched. If the session was created, is_created is set to 1. On error,
2151 * it's left untouched. Note that ua_sess_ptr is mandatory but is_created can
2152 * be NULL.
2153 *
2154 * Returns 0 on success or else a negative code which is either -ENOMEM or
2155 * -ENOTCONN which is the default code if the ustctl_create_session fails.
421cb601 2156 */
03f91eaa 2157static int find_or_create_ust_app_session(struct ltt_ust_session *usess,
3d8ca23b
DG
2158 struct ust_app *app, struct ust_app_session **ua_sess_ptr,
2159 int *is_created)
421cb601 2160{
3d8ca23b 2161 int ret, created = 0;
421cb601
DG
2162 struct ust_app_session *ua_sess;
2163
3d8ca23b
DG
2164 assert(usess);
2165 assert(app);
2166 assert(ua_sess_ptr);
2167
840cb59c 2168 health_code_update();
86acf0da 2169
421cb601
DG
2170 ua_sess = lookup_session_by_app(usess, app);
2171 if (ua_sess == NULL) {
d9bf3ca4 2172 DBG2("UST app pid: %d session id %" PRIu64 " not found, creating it",
852d0037 2173 app->pid, usess->id);
40bbd087 2174 ua_sess = alloc_ust_app_session();
421cb601
DG
2175 if (ua_sess == NULL) {
2176 /* Only malloc can failed so something is really wrong */
3d8ca23b
DG
2177 ret = -ENOMEM;
2178 goto error;
421cb601 2179 }
477d7741 2180 shadow_copy_session(ua_sess, usess, app);
3d8ca23b 2181 created = 1;
421cb601
DG
2182 }
2183
7972aab2
DG
2184 switch (usess->buffer_type) {
2185 case LTTNG_BUFFER_PER_PID:
2186 /* Init local registry. */
2187 ret = setup_buffer_reg_pid(ua_sess, app, NULL);
421cb601 2188 if (ret < 0) {
e64207cf 2189 delete_ust_app_session(-1, ua_sess, app);
7972aab2
DG
2190 goto error;
2191 }
2192 break;
2193 case LTTNG_BUFFER_PER_UID:
2194 /* Look for a global registry. If none exists, create one. */
d7ba1388 2195 ret = setup_buffer_reg_uid(usess, ua_sess, app, NULL);
7972aab2 2196 if (ret < 0) {
e64207cf 2197 delete_ust_app_session(-1, ua_sess, app);
7972aab2
DG
2198 goto error;
2199 }
2200 break;
2201 default:
2202 assert(0);
2203 ret = -EINVAL;
2204 goto error;
2205 }
2206
2207 health_code_update();
2208
2209 if (ua_sess->handle == -1) {
fb45065e 2210 pthread_mutex_lock(&app->sock_lock);
7972aab2 2211 ret = ustctl_create_session(app->sock);
fb45065e 2212 pthread_mutex_unlock(&app->sock_lock);
7972aab2
DG
2213 if (ret < 0) {
2214 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
2215 ERR("Creating session for app pid %d with ret %d",
ffe60014
DG
2216 app->pid, ret);
2217 } else {
2218 DBG("UST app creating session failed. Application is dead");
3757b385
DG
2219 /*
2220 * This is normal behavior, an application can die during the
2221 * creation process. Don't report an error so the execution can
2222 * continue normally. This will get flagged ENOTCONN and the
2223 * caller will handle it.
2224 */
2225 ret = 0;
ffe60014 2226 }
d0b96690 2227 delete_ust_app_session(-1, ua_sess, app);
3d8ca23b
DG
2228 if (ret != -ENOMEM) {
2229 /*
2230 * Tracer is probably gone or got an internal error so let's
2231 * behave like it will soon unregister or not usable.
2232 */
2233 ret = -ENOTCONN;
2234 }
2235 goto error;
421cb601
DG
2236 }
2237
7972aab2
DG
2238 ua_sess->handle = ret;
2239
2240 /* Add ust app session to app's HT */
d9bf3ca4
MD
2241 lttng_ht_node_init_u64(&ua_sess->node,
2242 ua_sess->tracing_id);
2243 lttng_ht_add_unique_u64(app->sessions, &ua_sess->node);
10b56aef
MD
2244 lttng_ht_node_init_ulong(&ua_sess->ust_objd_node, ua_sess->handle);
2245 lttng_ht_add_unique_ulong(app->ust_sessions_objd,
2246 &ua_sess->ust_objd_node);
7972aab2
DG
2247
2248 DBG2("UST app session created successfully with handle %d", ret);
2249 }
2250
2251 *ua_sess_ptr = ua_sess;
2252 if (is_created) {
2253 *is_created = created;
2254 }
2255
2256 /* Everything went well. */
2257 ret = 0;
2258
2259error:
2260 health_code_update();
2261 return ret;
2262}
2263
6a6b2068
JG
2264/*
2265 * Match function for a hash table lookup of ust_app_ctx.
2266 *
2267 * It matches an ust app context based on the context type and, in the case
2268 * of perf counters, their name.
2269 */
2270static int ht_match_ust_app_ctx(struct cds_lfht_node *node, const void *_key)
2271{
2272 struct ust_app_ctx *ctx;
bdf64013 2273 const struct lttng_ust_context_attr *key;
6a6b2068
JG
2274
2275 assert(node);
2276 assert(_key);
2277
2278 ctx = caa_container_of(node, struct ust_app_ctx, node.node);
2279 key = _key;
2280
2281 /* Context type */
2282 if (ctx->ctx.ctx != key->ctx) {
2283 goto no_match;
2284 }
2285
bdf64013
JG
2286 switch(key->ctx) {
2287 case LTTNG_UST_CONTEXT_PERF_THREAD_COUNTER:
6a6b2068 2288 if (strncmp(key->u.perf_counter.name,
bdf64013
JG
2289 ctx->ctx.u.perf_counter.name,
2290 sizeof(key->u.perf_counter.name))) {
2291 goto no_match;
2292 }
2293 break;
2294 case LTTNG_UST_CONTEXT_APP_CONTEXT:
2295 if (strcmp(key->u.app_ctx.provider_name,
2296 ctx->ctx.u.app_ctx.provider_name) ||
2297 strcmp(key->u.app_ctx.ctx_name,
2298 ctx->ctx.u.app_ctx.ctx_name)) {
6a6b2068
JG
2299 goto no_match;
2300 }
bdf64013
JG
2301 break;
2302 default:
2303 break;
6a6b2068
JG
2304 }
2305
2306 /* Match. */
2307 return 1;
2308
2309no_match:
2310 return 0;
2311}
2312
2313/*
2314 * Lookup for an ust app context from an lttng_ust_context.
2315 *
be184a0f 2316 * Must be called while holding RCU read side lock.
6a6b2068
JG
2317 * Return an ust_app_ctx object or NULL on error.
2318 */
2319static
2320struct ust_app_ctx *find_ust_app_context(struct lttng_ht *ht,
bdf64013 2321 struct lttng_ust_context_attr *uctx)
6a6b2068
JG
2322{
2323 struct lttng_ht_iter iter;
2324 struct lttng_ht_node_ulong *node;
2325 struct ust_app_ctx *app_ctx = NULL;
2326
2327 assert(uctx);
2328 assert(ht);
2329
2330 /* Lookup using the lttng_ust_context_type and a custom match fct. */
2331 cds_lfht_lookup(ht->ht, ht->hash_fct((void *) uctx->ctx, lttng_ht_seed),
2332 ht_match_ust_app_ctx, uctx, &iter.iter);
2333 node = lttng_ht_iter_get_node_ulong(&iter);
2334 if (!node) {
2335 goto end;
2336 }
2337
2338 app_ctx = caa_container_of(node, struct ust_app_ctx, node);
2339
2340end:
2341 return app_ctx;
2342}
2343
7972aab2
DG
2344/*
2345 * Create a context for the channel on the tracer.
2346 *
2347 * Called with UST app session lock held and a RCU read side lock.
2348 */
2349static
2350int create_ust_app_channel_context(struct ust_app_session *ua_sess,
bdf64013
JG
2351 struct ust_app_channel *ua_chan,
2352 struct lttng_ust_context_attr *uctx,
7972aab2
DG
2353 struct ust_app *app)
2354{
2355 int ret = 0;
7972aab2
DG
2356 struct ust_app_ctx *ua_ctx;
2357
2358 DBG2("UST app adding context to channel %s", ua_chan->name);
2359
6a6b2068
JG
2360 ua_ctx = find_ust_app_context(ua_chan->ctx, uctx);
2361 if (ua_ctx) {
7972aab2
DG
2362 ret = -EEXIST;
2363 goto error;
2364 }
2365
2366 ua_ctx = alloc_ust_app_ctx(uctx);
2367 if (ua_ctx == NULL) {
2368 /* malloc failed */
7682f304 2369 ret = -ENOMEM;
7972aab2
DG
2370 goto error;
2371 }
2372
2373 lttng_ht_node_init_ulong(&ua_ctx->node, (unsigned long) ua_ctx->ctx.ctx);
aa3514e9 2374 lttng_ht_add_ulong(ua_chan->ctx, &ua_ctx->node);
31746f93 2375 cds_list_add_tail(&ua_ctx->list, &ua_chan->ctx_list);
7972aab2
DG
2376
2377 ret = create_ust_channel_context(ua_chan, ua_ctx, app);
2378 if (ret < 0) {
2379 goto error;
2380 }
2381
2382error:
2383 return ret;
2384}
2385
2386/*
2387 * Enable on the tracer side a ust app event for the session and channel.
2388 *
2389 * Called with UST app session lock held.
2390 */
2391static
2392int enable_ust_app_event(struct ust_app_session *ua_sess,
2393 struct ust_app_event *ua_event, struct ust_app *app)
2394{
2395 int ret;
2396
2397 ret = enable_ust_event(app, ua_sess, ua_event);
2398 if (ret < 0) {
2399 goto error;
2400 }
2401
2402 ua_event->enabled = 1;
2403
2404error:
2405 return ret;
2406}
2407
2408/*
2409 * Disable on the tracer side a ust app event for the session and channel.
2410 */
2411static int disable_ust_app_event(struct ust_app_session *ua_sess,
2412 struct ust_app_event *ua_event, struct ust_app *app)
2413{
2414 int ret;
2415
2416 ret = disable_ust_event(app, ua_sess, ua_event);
2417 if (ret < 0) {
2418 goto error;
2419 }
2420
2421 ua_event->enabled = 0;
2422
2423error:
2424 return ret;
2425}
2426
2427/*
2428 * Lookup ust app channel for session and disable it on the tracer side.
2429 */
2430static
2431int disable_ust_app_channel(struct ust_app_session *ua_sess,
2432 struct ust_app_channel *ua_chan, struct ust_app *app)
2433{
2434 int ret;
2435
2436 ret = disable_ust_channel(app, ua_sess, ua_chan);
2437 if (ret < 0) {
2438 goto error;
2439 }
2440
2441 ua_chan->enabled = 0;
2442
2443error:
2444 return ret;
2445}
2446
2447/*
2448 * Lookup ust app channel for session and enable it on the tracer side. This
2449 * MUST be called with a RCU read side lock acquired.
2450 */
2451static int enable_ust_app_channel(struct ust_app_session *ua_sess,
2452 struct ltt_ust_channel *uchan, struct ust_app *app)
2453{
2454 int ret = 0;
2455 struct lttng_ht_iter iter;
2456 struct lttng_ht_node_str *ua_chan_node;
2457 struct ust_app_channel *ua_chan;
2458
2459 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
2460 ua_chan_node = lttng_ht_iter_get_node_str(&iter);
2461 if (ua_chan_node == NULL) {
d9bf3ca4 2462 DBG2("Unable to find channel %s in ust session id %" PRIu64,
7972aab2
DG
2463 uchan->name, ua_sess->tracing_id);
2464 goto error;
2465 }
2466
2467 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
2468
2469 ret = enable_ust_channel(app, ua_sess, ua_chan);
2470 if (ret < 0) {
2471 goto error;
2472 }
2473
2474error:
2475 return ret;
2476}
2477
2478/*
2479 * Ask the consumer to create a channel and get it if successful.
2480 *
fad1ed2f
JR
2481 * Called with UST app session lock held.
2482 *
7972aab2
DG
2483 * Return 0 on success or else a negative value.
2484 */
2485static int do_consumer_create_channel(struct ltt_ust_session *usess,
2486 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan,
2487 int bitness, struct ust_registry_session *registry)
2488{
2489 int ret;
2490 unsigned int nb_fd = 0;
2491 struct consumer_socket *socket;
2492
2493 assert(usess);
2494 assert(ua_sess);
2495 assert(ua_chan);
2496 assert(registry);
2497
2498 rcu_read_lock();
2499 health_code_update();
2500
2501 /* Get the right consumer socket for the application. */
2502 socket = consumer_find_socket_by_bitness(bitness, usess->consumer);
2503 if (!socket) {
2504 ret = -EINVAL;
2505 goto error;
2506 }
2507
2508 health_code_update();
2509
2510 /* Need one fd for the channel. */
2511 ret = lttng_fd_get(LTTNG_FD_APPS, 1);
2512 if (ret < 0) {
2513 ERR("Exhausted number of available FD upon create channel");
2514 goto error;
2515 }
2516
2517 /*
2518 * Ask consumer to create channel. The consumer will return the number of
2519 * stream we have to expect.
2520 */
2521 ret = ust_consumer_ask_channel(ua_sess, ua_chan, usess->consumer, socket,
2522 registry);
2523 if (ret < 0) {
2524 goto error_ask;
2525 }
2526
2527 /*
2528 * Compute the number of fd needed before receiving them. It must be 2 per
2529 * stream (2 being the default value here).
2530 */
2531 nb_fd = DEFAULT_UST_STREAM_FD_NUM * ua_chan->expected_stream_count;
2532
2533 /* Reserve the amount of file descriptor we need. */
2534 ret = lttng_fd_get(LTTNG_FD_APPS, nb_fd);
2535 if (ret < 0) {
2536 ERR("Exhausted number of available FD upon create channel");
2537 goto error_fd_get_stream;
2538 }
2539
2540 health_code_update();
2541
2542 /*
2543 * Now get the channel from the consumer. This call wil populate the stream
2544 * list of that channel and set the ust objects.
2545 */
d9078d0c
DG
2546 if (usess->consumer->enabled) {
2547 ret = ust_consumer_get_channel(socket, ua_chan);
2548 if (ret < 0) {
2549 goto error_destroy;
2550 }
7972aab2
DG
2551 }
2552
2553 rcu_read_unlock();
2554 return 0;
2555
2556error_destroy:
2557 lttng_fd_put(LTTNG_FD_APPS, nb_fd);
2558error_fd_get_stream:
2559 /*
2560 * Initiate a destroy channel on the consumer since we had an error
2561 * handling it on our side. The return value is of no importance since we
2562 * already have a ret value set by the previous error that we need to
2563 * return.
2564 */
2565 (void) ust_consumer_destroy_channel(socket, ua_chan);
2566error_ask:
2567 lttng_fd_put(LTTNG_FD_APPS, 1);
2568error:
2569 health_code_update();
2570 rcu_read_unlock();
2571 return ret;
2572}
2573
2574/*
2575 * Duplicate the ust data object of the ust app stream and save it in the
2576 * buffer registry stream.
2577 *
2578 * Return 0 on success or else a negative value.
2579 */
2580static int duplicate_stream_object(struct buffer_reg_stream *reg_stream,
2581 struct ust_app_stream *stream)
2582{
2583 int ret;
2584
2585 assert(reg_stream);
2586 assert(stream);
2587
2588 /* Reserve the amount of file descriptor we need. */
2589 ret = lttng_fd_get(LTTNG_FD_APPS, 2);
2590 if (ret < 0) {
2591 ERR("Exhausted number of available FD upon duplicate stream");
2592 goto error;
2593 }
2594
2595 /* Duplicate object for stream once the original is in the registry. */
2596 ret = ustctl_duplicate_ust_object_data(&stream->obj,
2597 reg_stream->obj.ust);
2598 if (ret < 0) {
2599 ERR("Duplicate stream obj from %p to %p failed with ret %d",
2600 reg_stream->obj.ust, stream->obj, ret);
2601 lttng_fd_put(LTTNG_FD_APPS, 2);
2602 goto error;
2603 }
2604 stream->handle = stream->obj->handle;
2605
2606error:
2607 return ret;
2608}
2609
2610/*
2611 * Duplicate the ust data object of the ust app. channel and save it in the
2612 * buffer registry channel.
2613 *
2614 * Return 0 on success or else a negative value.
2615 */
2616static int duplicate_channel_object(struct buffer_reg_channel *reg_chan,
2617 struct ust_app_channel *ua_chan)
2618{
2619 int ret;
2620
2621 assert(reg_chan);
2622 assert(ua_chan);
2623
2624 /* Need two fds for the channel. */
2625 ret = lttng_fd_get(LTTNG_FD_APPS, 1);
2626 if (ret < 0) {
2627 ERR("Exhausted number of available FD upon duplicate channel");
2628 goto error_fd_get;
2629 }
2630
2631 /* Duplicate object for stream once the original is in the registry. */
2632 ret = ustctl_duplicate_ust_object_data(&ua_chan->obj, reg_chan->obj.ust);
2633 if (ret < 0) {
2634 ERR("Duplicate channel obj from %p to %p failed with ret: %d",
2635 reg_chan->obj.ust, ua_chan->obj, ret);
2636 goto error;
2637 }
2638 ua_chan->handle = ua_chan->obj->handle;
2639
2640 return 0;
2641
2642error:
2643 lttng_fd_put(LTTNG_FD_APPS, 1);
2644error_fd_get:
2645 return ret;
2646}
2647
2648/*
2649 * For a given channel buffer registry, setup all streams of the given ust
2650 * application channel.
2651 *
2652 * Return 0 on success or else a negative value.
2653 */
2654static int setup_buffer_reg_streams(struct buffer_reg_channel *reg_chan,
fb45065e
MD
2655 struct ust_app_channel *ua_chan,
2656 struct ust_app *app)
7972aab2
DG
2657{
2658 int ret = 0;
2659 struct ust_app_stream *stream, *stmp;
2660
2661 assert(reg_chan);
2662 assert(ua_chan);
2663
2664 DBG2("UST app setup buffer registry stream");
2665
2666 /* Send all streams to application. */
2667 cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
2668 struct buffer_reg_stream *reg_stream;
2669
2670 ret = buffer_reg_stream_create(&reg_stream);
2671 if (ret < 0) {
2672 goto error;
2673 }
2674
2675 /*
2676 * Keep original pointer and nullify it in the stream so the delete
2677 * stream call does not release the object.
2678 */
2679 reg_stream->obj.ust = stream->obj;
2680 stream->obj = NULL;
2681 buffer_reg_stream_add(reg_stream, reg_chan);
421cb601 2682
7972aab2
DG
2683 /* We don't need the streams anymore. */
2684 cds_list_del(&stream->list);
fb45065e 2685 delete_ust_app_stream(-1, stream, app);
7972aab2 2686 }
421cb601 2687
7972aab2
DG
2688error:
2689 return ret;
2690}
2691
2692/*
2693 * Create a buffer registry channel for the given session registry and
2694 * application channel object. If regp pointer is valid, it's set with the
2695 * created object. Important, the created object is NOT added to the session
2696 * registry hash table.
2697 *
2698 * Return 0 on success else a negative value.
2699 */
2700static int create_buffer_reg_channel(struct buffer_reg_session *reg_sess,
2701 struct ust_app_channel *ua_chan, struct buffer_reg_channel **regp)
2702{
2703 int ret;
2704 struct buffer_reg_channel *reg_chan = NULL;
2705
2706 assert(reg_sess);
2707 assert(ua_chan);
2708
2709 DBG2("UST app creating buffer registry channel for %s", ua_chan->name);
2710
2711 /* Create buffer registry channel. */
2712 ret = buffer_reg_channel_create(ua_chan->tracing_channel_id, &reg_chan);
2713 if (ret < 0) {
2714 goto error_create;
421cb601 2715 }
7972aab2
DG
2716 assert(reg_chan);
2717 reg_chan->consumer_key = ua_chan->key;
8c924c7b 2718 reg_chan->subbuf_size = ua_chan->attr.subbuf_size;
d07ceecd 2719 reg_chan->num_subbuf = ua_chan->attr.num_subbuf;
421cb601 2720
7972aab2
DG
2721 /* Create and add a channel registry to session. */
2722 ret = ust_registry_channel_add(reg_sess->reg.ust,
2723 ua_chan->tracing_channel_id);
2724 if (ret < 0) {
2725 goto error;
d88aee68 2726 }
7972aab2 2727 buffer_reg_channel_add(reg_sess, reg_chan);
d88aee68 2728
7972aab2
DG
2729 if (regp) {
2730 *regp = reg_chan;
3d8ca23b 2731 }
d88aee68 2732
7972aab2 2733 return 0;
3d8ca23b
DG
2734
2735error:
7972aab2
DG
2736 /* Safe because the registry channel object was not added to any HT. */
2737 buffer_reg_channel_destroy(reg_chan, LTTNG_DOMAIN_UST);
2738error_create:
3d8ca23b 2739 return ret;
421cb601
DG
2740}
2741
55cc08a6 2742/*
7972aab2
DG
2743 * Setup buffer registry channel for the given session registry and application
2744 * channel object. If regp pointer is valid, it's set with the created object.
d0b96690 2745 *
7972aab2 2746 * Return 0 on success else a negative value.
55cc08a6 2747 */
7972aab2 2748static int setup_buffer_reg_channel(struct buffer_reg_session *reg_sess,
fb45065e
MD
2749 struct ust_app_channel *ua_chan, struct buffer_reg_channel *reg_chan,
2750 struct ust_app *app)
55cc08a6 2751{
7972aab2 2752 int ret;
55cc08a6 2753
7972aab2
DG
2754 assert(reg_sess);
2755 assert(reg_chan);
2756 assert(ua_chan);
2757 assert(ua_chan->obj);
55cc08a6 2758
7972aab2 2759 DBG2("UST app setup buffer registry channel for %s", ua_chan->name);
55cc08a6 2760
7972aab2 2761 /* Setup all streams for the registry. */
fb45065e 2762 ret = setup_buffer_reg_streams(reg_chan, ua_chan, app);
7972aab2 2763 if (ret < 0) {
55cc08a6
DG
2764 goto error;
2765 }
2766
7972aab2
DG
2767 reg_chan->obj.ust = ua_chan->obj;
2768 ua_chan->obj = NULL;
55cc08a6 2769
7972aab2 2770 return 0;
55cc08a6
DG
2771
2772error:
7972aab2
DG
2773 buffer_reg_channel_remove(reg_sess, reg_chan);
2774 buffer_reg_channel_destroy(reg_chan, LTTNG_DOMAIN_UST);
55cc08a6
DG
2775 return ret;
2776}
2777
edb67388 2778/*
7972aab2 2779 * Send buffer registry channel to the application.
d0b96690 2780 *
7972aab2 2781 * Return 0 on success else a negative value.
edb67388 2782 */
7972aab2
DG
2783static int send_channel_uid_to_ust(struct buffer_reg_channel *reg_chan,
2784 struct ust_app *app, struct ust_app_session *ua_sess,
2785 struct ust_app_channel *ua_chan)
edb67388
DG
2786{
2787 int ret;
7972aab2 2788 struct buffer_reg_stream *reg_stream;
edb67388 2789
7972aab2
DG
2790 assert(reg_chan);
2791 assert(app);
2792 assert(ua_sess);
2793 assert(ua_chan);
2794
2795 DBG("UST app sending buffer registry channel to ust sock %d", app->sock);
2796
2797 ret = duplicate_channel_object(reg_chan, ua_chan);
edb67388
DG
2798 if (ret < 0) {
2799 goto error;
2800 }
2801
7972aab2
DG
2802 /* Send channel to the application. */
2803 ret = ust_consumer_send_channel_to_ust(app, ua_sess, ua_chan);
a7169585
MD
2804 if (ret == -EPIPE || ret == -LTTNG_UST_ERR_EXITING) {
2805 ret = -ENOTCONN; /* Caused by app exiting. */
2806 goto error;
2807 } else if (ret < 0) {
7972aab2
DG
2808 goto error;
2809 }
2810
2811 health_code_update();
2812
2813 /* Send all streams to application. */
2814 pthread_mutex_lock(&reg_chan->stream_list_lock);
2815 cds_list_for_each_entry(reg_stream, &reg_chan->streams, lnode) {
2816 struct ust_app_stream stream;
2817
2818 ret = duplicate_stream_object(reg_stream, &stream);
2819 if (ret < 0) {
2820 goto error_stream_unlock;
2821 }
2822
2823 ret = ust_consumer_send_stream_to_ust(app, ua_chan, &stream);
2824 if (ret < 0) {
fb45065e 2825 (void) release_ust_app_stream(-1, &stream, app);
a7169585
MD
2826 if (ret == -EPIPE || ret == -LTTNG_UST_ERR_EXITING) {
2827 ret = -ENOTCONN; /* Caused by app exiting. */
a7169585 2828 }
7972aab2
DG
2829 goto error_stream_unlock;
2830 }
edb67388 2831
7972aab2
DG
2832 /*
2833 * The return value is not important here. This function will output an
2834 * error if needed.
2835 */
fb45065e 2836 (void) release_ust_app_stream(-1, &stream, app);
7972aab2
DG
2837 }
2838 ua_chan->is_sent = 1;
2839
2840error_stream_unlock:
2841 pthread_mutex_unlock(&reg_chan->stream_list_lock);
edb67388
DG
2842error:
2843 return ret;
2844}
2845
9730260e 2846/*
7972aab2
DG
2847 * Create and send to the application the created buffers with per UID buffers.
2848 *
9acdc1d6 2849 * This MUST be called with a RCU read side lock acquired.
71e0a100 2850 * The session list lock and the session's lock must be acquired.
9acdc1d6 2851 *
7972aab2 2852 * Return 0 on success else a negative value.
9730260e 2853 */
7972aab2
DG
2854static int create_channel_per_uid(struct ust_app *app,
2855 struct ltt_ust_session *usess, struct ust_app_session *ua_sess,
2856 struct ust_app_channel *ua_chan)
9730260e
DG
2857{
2858 int ret;
7972aab2
DG
2859 struct buffer_reg_uid *reg_uid;
2860 struct buffer_reg_channel *reg_chan;
9730260e 2861
7972aab2
DG
2862 assert(app);
2863 assert(usess);
2864 assert(ua_sess);
2865 assert(ua_chan);
2866
2867 DBG("UST app creating channel %s with per UID buffers", ua_chan->name);
2868
2869 reg_uid = buffer_reg_uid_find(usess->id, app->bits_per_long, app->uid);
2870 /*
2871 * The session creation handles the creation of this global registry
2872 * object. If none can be find, there is a code flow problem or a
2873 * teardown race.
2874 */
2875 assert(reg_uid);
2876
2877 reg_chan = buffer_reg_channel_find(ua_chan->tracing_channel_id,
2878 reg_uid);
2721f7ea
JG
2879 if (reg_chan) {
2880 goto send_channel;
2881 }
7972aab2 2882
2721f7ea
JG
2883 /* Create the buffer registry channel object. */
2884 ret = create_buffer_reg_channel(reg_uid->registry, ua_chan, &reg_chan);
2885 if (ret < 0) {
2886 ERR("Error creating the UST channel \"%s\" registry instance",
f14256d6 2887 ua_chan->name);
2721f7ea
JG
2888 goto error;
2889 }
f14256d6 2890
2721f7ea
JG
2891 /*
2892 * Create the buffers on the consumer side. This call populates the
2893 * ust app channel object with all streams and data object.
2894 */
2895 ret = do_consumer_create_channel(usess, ua_sess, ua_chan,
2896 app->bits_per_long, reg_uid->registry->reg.ust);
2897 if (ret < 0) {
2898 ERR("Error creating UST channel \"%s\" on the consumer daemon",
2899 ua_chan->name);
7972aab2
DG
2900
2901 /*
2721f7ea
JG
2902 * Let's remove the previously created buffer registry channel so
2903 * it's not visible anymore in the session registry.
7972aab2 2904 */
2721f7ea
JG
2905 ust_registry_channel_del_free(reg_uid->registry->reg.ust,
2906 ua_chan->tracing_channel_id, false);
2907 buffer_reg_channel_remove(reg_uid->registry, reg_chan);
2908 buffer_reg_channel_destroy(reg_chan, LTTNG_DOMAIN_UST);
2909 goto error;
7972aab2
DG
2910 }
2911
2721f7ea
JG
2912 /*
2913 * Setup the streams and add it to the session registry.
2914 */
2915 ret = setup_buffer_reg_channel(reg_uid->registry,
2916 ua_chan, reg_chan, app);
2917 if (ret < 0) {
2918 ERR("Error setting up UST channel \"%s\"", ua_chan->name);
2919 goto error;
2920 }
2921
2922 {
e9404c27
JG
2923 enum lttng_error_code cmd_ret;
2924 struct ltt_session *session;
2925 uint64_t chan_reg_key;
2926 struct ust_registry_channel *chan_reg;
2927
e9404c27
JG
2928 chan_reg_key = ua_chan->tracing_channel_id;
2929
2930 pthread_mutex_lock(&reg_uid->registry->reg.ust->lock);
2931 chan_reg = ust_registry_channel_find(reg_uid->registry->reg.ust,
2932 chan_reg_key);
2933 assert(chan_reg);
2934 chan_reg->consumer_key = ua_chan->key;
2935 chan_reg = NULL;
2936 pthread_mutex_unlock(&reg_uid->registry->reg.ust->lock);
2937
2938 session = session_find_by_id(ua_sess->tracing_id);
2939 assert(session);
2940
71e0a100
JG
2941 assert(pthread_mutex_trylock(&session->lock));
2942 assert(session_trylock_list());
e9404c27
JG
2943 cmd_ret = notification_thread_command_add_channel(
2944 notification_thread_handle, session->name,
2945 ua_sess->euid, ua_sess->egid,
2946 ua_chan->name,
2947 ua_chan->key,
2948 LTTNG_DOMAIN_UST,
2949 ua_chan->attr.subbuf_size * ua_chan->attr.num_subbuf);
e9404c27
JG
2950 if (cmd_ret != LTTNG_OK) {
2951 ret = - (int) cmd_ret;
2952 ERR("Failed to add channel to notification thread");
2953 goto error;
2954 }
2955 }
2956
2721f7ea 2957send_channel:
66ff8e3f
JG
2958 /* Send buffers to the application. */
2959 ret = send_channel_uid_to_ust(reg_chan, app, ua_sess, ua_chan);
2960 if (ret < 0) {
2961 if (ret != -ENOTCONN) {
2962 ERR("Error sending channel to application");
2963 }
2964 goto error;
2965 }
2966
9730260e
DG
2967error:
2968 return ret;
2969}
2970
78f0bacd 2971/*
7972aab2
DG
2972 * Create and send to the application the created buffers with per PID buffers.
2973 *
fad1ed2f 2974 * Called with UST app session lock held.
71e0a100 2975 * The session list lock and the session's lock must be acquired.
fad1ed2f 2976 *
7972aab2 2977 * Return 0 on success else a negative value.
78f0bacd 2978 */
7972aab2
DG
2979static int create_channel_per_pid(struct ust_app *app,
2980 struct ltt_ust_session *usess, struct ust_app_session *ua_sess,
2981 struct ust_app_channel *ua_chan)
78f0bacd 2982{
8535a6d9 2983 int ret;
7972aab2 2984 struct ust_registry_session *registry;
e9404c27
JG
2985 enum lttng_error_code cmd_ret;
2986 struct ltt_session *session;
2987 uint64_t chan_reg_key;
2988 struct ust_registry_channel *chan_reg;
78f0bacd 2989
7972aab2
DG
2990 assert(app);
2991 assert(usess);
2992 assert(ua_sess);
2993 assert(ua_chan);
2994
2995 DBG("UST app creating channel %s with per PID buffers", ua_chan->name);
2996
2997 rcu_read_lock();
2998
2999 registry = get_session_registry(ua_sess);
fad1ed2f 3000 /* The UST app session lock is held, registry shall not be null. */
7972aab2
DG
3001 assert(registry);
3002
3003 /* Create and add a new channel registry to session. */
3004 ret = ust_registry_channel_add(registry, ua_chan->key);
78f0bacd 3005 if (ret < 0) {
f14256d6
MD
3006 ERR("Error creating the UST channel \"%s\" registry instance",
3007 ua_chan->name);
78f0bacd
DG
3008 goto error;
3009 }
3010
7972aab2
DG
3011 /* Create and get channel on the consumer side. */
3012 ret = do_consumer_create_channel(usess, ua_sess, ua_chan,
3013 app->bits_per_long, registry);
3014 if (ret < 0) {
f14256d6
MD
3015 ERR("Error creating UST channel \"%s\" on the consumer daemon",
3016 ua_chan->name);
7972aab2
DG
3017 goto error;
3018 }
3019
3020 ret = send_channel_pid_to_ust(app, ua_sess, ua_chan);
3021 if (ret < 0) {
a7169585
MD
3022 if (ret != -ENOTCONN) {
3023 ERR("Error sending channel to application");
3024 }
7972aab2
DG
3025 goto error;
3026 }
8535a6d9 3027
e9404c27
JG
3028 session = session_find_by_id(ua_sess->tracing_id);
3029 assert(session);
3030
3031 chan_reg_key = ua_chan->key;
3032 pthread_mutex_lock(&registry->lock);
3033 chan_reg = ust_registry_channel_find(registry, chan_reg_key);
3034 assert(chan_reg);
3035 chan_reg->consumer_key = ua_chan->key;
3036 pthread_mutex_unlock(&registry->lock);
3037
71e0a100
JG
3038 assert(pthread_mutex_trylock(&session->lock));
3039 assert(session_trylock_list());
3040
e9404c27
JG
3041 cmd_ret = notification_thread_command_add_channel(
3042 notification_thread_handle, session->name,
3043 ua_sess->euid, ua_sess->egid,
3044 ua_chan->name,
3045 ua_chan->key,
3046 LTTNG_DOMAIN_UST,
3047 ua_chan->attr.subbuf_size * ua_chan->attr.num_subbuf);
3048 if (cmd_ret != LTTNG_OK) {
3049 ret = - (int) cmd_ret;
3050 ERR("Failed to add channel to notification thread");
3051 goto error;
3052 }
3053
78f0bacd 3054error:
7972aab2 3055 rcu_read_unlock();
78f0bacd
DG
3056 return ret;
3057}
3058
3059/*
7972aab2
DG
3060 * From an already allocated ust app channel, create the channel buffers if
3061 * need and send it to the application. This MUST be called with a RCU read
3062 * side lock acquired.
3063 *
fad1ed2f
JR
3064 * Called with UST app session lock held.
3065 *
a7169585
MD
3066 * Return 0 on success or else a negative value. Returns -ENOTCONN if
3067 * the application exited concurrently.
78f0bacd 3068 */
7972aab2
DG
3069static int do_create_channel(struct ust_app *app,
3070 struct ltt_ust_session *usess, struct ust_app_session *ua_sess,
3071 struct ust_app_channel *ua_chan)
78f0bacd 3072{
7972aab2 3073 int ret;
78f0bacd 3074
7972aab2
DG
3075 assert(app);
3076 assert(usess);
3077 assert(ua_sess);
3078 assert(ua_chan);
3079
3080 /* Handle buffer type before sending the channel to the application. */
3081 switch (usess->buffer_type) {
3082 case LTTNG_BUFFER_PER_UID:
3083 {
3084 ret = create_channel_per_uid(app, usess, ua_sess, ua_chan);
3085 if (ret < 0) {
3086 goto error;
3087 }
3088 break;
3089 }
3090 case LTTNG_BUFFER_PER_PID:
3091 {
3092 ret = create_channel_per_pid(app, usess, ua_sess, ua_chan);
3093 if (ret < 0) {
3094 goto error;
3095 }
3096 break;
3097 }
3098 default:
3099 assert(0);
3100 ret = -EINVAL;
78f0bacd
DG
3101 goto error;
3102 }
3103
7972aab2
DG
3104 /* Initialize ust objd object using the received handle and add it. */
3105 lttng_ht_node_init_ulong(&ua_chan->ust_objd_node, ua_chan->handle);
3106 lttng_ht_add_unique_ulong(app->ust_objd, &ua_chan->ust_objd_node);
78f0bacd 3107
7972aab2
DG
3108 /* If channel is not enabled, disable it on the tracer */
3109 if (!ua_chan->enabled) {
3110 ret = disable_ust_channel(app, ua_sess, ua_chan);
3111 if (ret < 0) {
3112 goto error;
3113 }
78f0bacd
DG
3114 }
3115
3116error:
3117 return ret;
3118}
3119
284d8f55 3120/*
4d710ac2
DG
3121 * Create UST app channel and create it on the tracer. Set ua_chanp of the
3122 * newly created channel if not NULL.
d0b96690 3123 *
36b588ed 3124 * Called with UST app session lock and RCU read-side lock held.
7972aab2 3125 *
a7169585
MD
3126 * Return 0 on success or else a negative value. Returns -ENOTCONN if
3127 * the application exited concurrently.
284d8f55 3128 */
4d710ac2
DG
3129static int create_ust_app_channel(struct ust_app_session *ua_sess,
3130 struct ltt_ust_channel *uchan, struct ust_app *app,
7972aab2 3131 enum lttng_ust_chan_type type, struct ltt_ust_session *usess,
4d710ac2 3132 struct ust_app_channel **ua_chanp)
5b4a0ec0
DG
3133{
3134 int ret = 0;
bec39940
DG
3135 struct lttng_ht_iter iter;
3136 struct lttng_ht_node_str *ua_chan_node;
5b4a0ec0
DG
3137 struct ust_app_channel *ua_chan;
3138
3139 /* Lookup channel in the ust app session */
bec39940
DG
3140 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
3141 ua_chan_node = lttng_ht_iter_get_node_str(&iter);
fc34caaa 3142 if (ua_chan_node != NULL) {
5b4a0ec0 3143 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
fc34caaa 3144 goto end;
5b4a0ec0
DG
3145 }
3146
d0b96690 3147 ua_chan = alloc_ust_app_channel(uchan->name, ua_sess, &uchan->attr);
fc34caaa
DG
3148 if (ua_chan == NULL) {
3149 /* Only malloc can fail here */
4d710ac2 3150 ret = -ENOMEM;
094d1690 3151 goto error_alloc;
fc34caaa
DG
3152 }
3153 shadow_copy_channel(ua_chan, uchan);
3154
ffe60014
DG
3155 /* Set channel type. */
3156 ua_chan->attr.type = type;
3157
7972aab2 3158 ret = do_create_channel(app, usess, ua_sess, ua_chan);
5b4a0ec0
DG
3159 if (ret < 0) {
3160 goto error;
3161 }
3162
fc34caaa 3163 DBG2("UST app create channel %s for PID %d completed", ua_chan->name,
852d0037 3164 app->pid);
fc34caaa 3165
d0b96690
DG
3166 /* Only add the channel if successful on the tracer side. */
3167 lttng_ht_add_unique_str(ua_sess->channels, &ua_chan->node);
fc34caaa 3168end:
4d710ac2
DG
3169 if (ua_chanp) {
3170 *ua_chanp = ua_chan;
3171 }
3172
3173 /* Everything went well. */
3174 return 0;
5b4a0ec0
DG
3175
3176error:
d0b96690 3177 delete_ust_app_channel(ua_chan->is_sent ? app->sock : -1, ua_chan, app);
094d1690 3178error_alloc:
4d710ac2 3179 return ret;
5b4a0ec0
DG
3180}
3181
3182/*
3183 * Create UST app event and create it on the tracer side.
d0b96690
DG
3184 *
3185 * Called with ust app session mutex held.
5b4a0ec0 3186 */
edb67388
DG
3187static
3188int create_ust_app_event(struct ust_app_session *ua_sess,
3189 struct ust_app_channel *ua_chan, struct ltt_ust_event *uevent,
3190 struct ust_app *app)
284d8f55 3191{
edb67388 3192 int ret = 0;
5b4a0ec0 3193 struct ust_app_event *ua_event;
284d8f55 3194
5b4a0ec0 3195 /* Get event node */
18eace3b 3196 ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name,
39c5a3a7 3197 uevent->filter, uevent->attr.loglevel, uevent->exclusion);
18eace3b 3198 if (ua_event != NULL) {
fc34caaa 3199 ret = -EEXIST;
edb67388
DG
3200 goto end;
3201 }
5b4a0ec0 3202
edb67388
DG
3203 /* Does not exist so create one */
3204 ua_event = alloc_ust_app_event(uevent->attr.name, &uevent->attr);
3205 if (ua_event == NULL) {
3206 /* Only malloc can failed so something is really wrong */
3207 ret = -ENOMEM;
fc34caaa 3208 goto end;
5b4a0ec0 3209 }
edb67388 3210 shadow_copy_event(ua_event, uevent);
5b4a0ec0 3211
edb67388 3212 /* Create it on the tracer side */
5b4a0ec0 3213 ret = create_ust_event(app, ua_sess, ua_chan, ua_event);
284d8f55 3214 if (ret < 0) {
fc34caaa 3215 /* Not found previously means that it does not exist on the tracer */
76f66f63 3216 assert(ret != -LTTNG_UST_ERR_EXIST);
284d8f55
DG
3217 goto error;
3218 }
3219
d0b96690 3220 add_unique_ust_app_event(ua_chan, ua_event);
284d8f55 3221
fc34caaa 3222 DBG2("UST app create event %s for PID %d completed", ua_event->name,
852d0037 3223 app->pid);
7f79d3a1 3224
edb67388 3225end:
fc34caaa
DG
3226 return ret;
3227
5b4a0ec0 3228error:
fc34caaa 3229 /* Valid. Calling here is already in a read side lock */
fb45065e 3230 delete_ust_app_event(-1, ua_event, app);
edb67388 3231 return ret;
5b4a0ec0
DG
3232}
3233
3234/*
3235 * Create UST metadata and open it on the tracer side.
d0b96690 3236 *
7972aab2 3237 * Called with UST app session lock held and RCU read side lock.
5b4a0ec0
DG
3238 */
3239static int create_ust_app_metadata(struct ust_app_session *ua_sess,
ad7a9107 3240 struct ust_app *app, struct consumer_output *consumer)