Fix: leak of trace_path on error in ust_app_snapshot_record
[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(
470cc211
JG
253 ua_sess->tracing_id, ua_sess->bits_per_long,
254 ua_sess->real_credentials.uid);
7972aab2
DG
255 if (!reg_uid) {
256 goto error;
257 }
258 registry = reg_uid->registry->reg.ust;
259 break;
260 }
261 default:
262 assert(0);
263 };
264
265error:
266 return registry;
267}
268
55cc08a6
DG
269/*
270 * Delete ust context safely. RCU read lock must be held before calling
271 * this function.
272 */
273static
fb45065e
MD
274void delete_ust_app_ctx(int sock, struct ust_app_ctx *ua_ctx,
275 struct ust_app *app)
55cc08a6 276{
ffe60014
DG
277 int ret;
278
279 assert(ua_ctx);
280
55cc08a6 281 if (ua_ctx->obj) {
fb45065e 282 pthread_mutex_lock(&app->sock_lock);
ffe60014 283 ret = ustctl_release_object(sock, ua_ctx->obj);
fb45065e 284 pthread_mutex_unlock(&app->sock_lock);
d0b96690
DG
285 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
286 ERR("UST app sock %d release ctx obj handle %d failed with ret %d",
287 sock, ua_ctx->obj->handle, ret);
ffe60014 288 }
55cc08a6
DG
289 free(ua_ctx->obj);
290 }
291 free(ua_ctx);
292}
293
d80a6244
DG
294/*
295 * Delete ust app event safely. RCU read lock must be held before calling
296 * this function.
297 */
8b366481 298static
fb45065e
MD
299void delete_ust_app_event(int sock, struct ust_app_event *ua_event,
300 struct ust_app *app)
d80a6244 301{
ffe60014
DG
302 int ret;
303
304 assert(ua_event);
305
53a80697 306 free(ua_event->filter);
951f0b71
JI
307 if (ua_event->exclusion != NULL)
308 free(ua_event->exclusion);
edb67388 309 if (ua_event->obj != NULL) {
fb45065e 310 pthread_mutex_lock(&app->sock_lock);
ffe60014 311 ret = ustctl_release_object(sock, ua_event->obj);
fb45065e 312 pthread_mutex_unlock(&app->sock_lock);
ffe60014
DG
313 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
314 ERR("UST app sock %d release event obj failed with ret %d",
315 sock, ret);
316 }
edb67388
DG
317 free(ua_event->obj);
318 }
d80a6244
DG
319 free(ua_event);
320}
321
322/*
7972aab2
DG
323 * Release ust data object of the given stream.
324 *
325 * Return 0 on success or else a negative value.
d80a6244 326 */
fb45065e
MD
327static int release_ust_app_stream(int sock, struct ust_app_stream *stream,
328 struct ust_app *app)
d80a6244 329{
7972aab2 330 int ret = 0;
ffe60014
DG
331
332 assert(stream);
333
8b366481 334 if (stream->obj) {
fb45065e 335 pthread_mutex_lock(&app->sock_lock);
ffe60014 336 ret = ustctl_release_object(sock, stream->obj);
fb45065e 337 pthread_mutex_unlock(&app->sock_lock);
ffe60014
DG
338 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
339 ERR("UST app sock %d release stream obj failed with ret %d",
340 sock, ret);
341 }
4063050c 342 lttng_fd_put(LTTNG_FD_APPS, 2);
8b366481
DG
343 free(stream->obj);
344 }
7972aab2
DG
345
346 return ret;
347}
348
349/*
350 * Delete ust app stream safely. RCU read lock must be held before calling
351 * this function.
352 */
353static
fb45065e
MD
354void delete_ust_app_stream(int sock, struct ust_app_stream *stream,
355 struct ust_app *app)
7972aab2
DG
356{
357 assert(stream);
358
fb45065e 359 (void) release_ust_app_stream(sock, stream, app);
84cd17c6 360 free(stream);
d80a6244
DG
361}
362
36b588ed
MD
363/*
364 * We need to execute ht_destroy outside of RCU read-side critical
0b2dc8df
MD
365 * section and outside of call_rcu thread, so we postpone its execution
366 * using ht_cleanup_push. It is simpler than to change the semantic of
367 * the many callers of delete_ust_app_session().
36b588ed
MD
368 */
369static
370void delete_ust_app_channel_rcu(struct rcu_head *head)
371{
372 struct ust_app_channel *ua_chan =
373 caa_container_of(head, struct ust_app_channel, rcu_head);
374
0b2dc8df
MD
375 ht_cleanup_push(ua_chan->ctx);
376 ht_cleanup_push(ua_chan->events);
36b588ed
MD
377 free(ua_chan);
378}
379
fb83fe64
JD
380/*
381 * Extract the lost packet or discarded events counter when the channel is
382 * being deleted and store the value in the parent channel so we can
383 * access it from lttng list and at stop/destroy.
82cac6d2
JG
384 *
385 * The session list lock must be held by the caller.
fb83fe64
JD
386 */
387static
388void save_per_pid_lost_discarded_counters(struct ust_app_channel *ua_chan)
389{
390 uint64_t discarded = 0, lost = 0;
391 struct ltt_session *session;
392 struct ltt_ust_channel *uchan;
393
394 if (ua_chan->attr.type != LTTNG_UST_CHAN_PER_CPU) {
395 return;
396 }
397
398 rcu_read_lock();
399 session = session_find_by_id(ua_chan->session->tracing_id);
d68ec974
JG
400 if (!session || !session->ust_session) {
401 /*
402 * Not finding the session is not an error because there are
403 * multiple ways the channels can be torn down.
404 *
405 * 1) The session daemon can initiate the destruction of the
406 * ust app session after receiving a destroy command or
407 * during its shutdown/teardown.
408 * 2) The application, since we are in per-pid tracing, is
409 * unregistering and tearing down its ust app session.
410 *
411 * Both paths are protected by the session list lock which
412 * ensures that the accounting of lost packets and discarded
413 * events is done exactly once. The session is then unpublished
414 * from the session list, resulting in this condition.
415 */
fb83fe64
JD
416 goto end;
417 }
418
419 if (ua_chan->attr.overwrite) {
420 consumer_get_lost_packets(ua_chan->session->tracing_id,
421 ua_chan->key, session->ust_session->consumer,
422 &lost);
423 } else {
424 consumer_get_discarded_events(ua_chan->session->tracing_id,
425 ua_chan->key, session->ust_session->consumer,
426 &discarded);
427 }
428 uchan = trace_ust_find_channel_by_name(
429 session->ust_session->domain_global.channels,
430 ua_chan->name);
431 if (!uchan) {
432 ERR("Missing UST channel to store discarded counters");
433 goto end;
434 }
435
436 uchan->per_pid_closed_app_discarded += discarded;
437 uchan->per_pid_closed_app_lost += lost;
438
439end:
440 rcu_read_unlock();
e32d7f27
JG
441 if (session) {
442 session_put(session);
443 }
fb83fe64
JD
444}
445
d80a6244
DG
446/*
447 * Delete ust app channel safely. RCU read lock must be held before calling
448 * this function.
82cac6d2
JG
449 *
450 * The session list lock must be held by the caller.
d80a6244 451 */
8b366481 452static
d0b96690
DG
453void delete_ust_app_channel(int sock, struct ust_app_channel *ua_chan,
454 struct ust_app *app)
d80a6244
DG
455{
456 int ret;
bec39940 457 struct lttng_ht_iter iter;
d80a6244 458 struct ust_app_event *ua_event;
55cc08a6 459 struct ust_app_ctx *ua_ctx;
030a66fa 460 struct ust_app_stream *stream, *stmp;
7972aab2 461 struct ust_registry_session *registry;
d80a6244 462
ffe60014
DG
463 assert(ua_chan);
464
465 DBG3("UST app deleting channel %s", ua_chan->name);
466
55cc08a6 467 /* Wipe stream */
d80a6244 468 cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
84cd17c6 469 cds_list_del(&stream->list);
fb45065e 470 delete_ust_app_stream(sock, stream, app);
d80a6244
DG
471 }
472
55cc08a6 473 /* Wipe context */
bec39940 474 cds_lfht_for_each_entry(ua_chan->ctx->ht, &iter.iter, ua_ctx, node.node) {
31746f93 475 cds_list_del(&ua_ctx->list);
bec39940 476 ret = lttng_ht_del(ua_chan->ctx, &iter);
55cc08a6 477 assert(!ret);
fb45065e 478 delete_ust_app_ctx(sock, ua_ctx, app);
55cc08a6 479 }
d80a6244 480
55cc08a6 481 /* Wipe events */
bec39940
DG
482 cds_lfht_for_each_entry(ua_chan->events->ht, &iter.iter, ua_event,
483 node.node) {
484 ret = lttng_ht_del(ua_chan->events, &iter);
525b0740 485 assert(!ret);
fb45065e 486 delete_ust_app_event(sock, ua_event, app);
d80a6244 487 }
edb67388 488
c8335706
MD
489 if (ua_chan->session->buffer_type == LTTNG_BUFFER_PER_PID) {
490 /* Wipe and free registry from session registry. */
491 registry = get_session_registry(ua_chan->session);
492 if (registry) {
e9404c27 493 ust_registry_channel_del_free(registry, ua_chan->key,
e38d96f9
MD
494 sock >= 0);
495 }
45798a31
JG
496 /*
497 * A negative socket can be used by the caller when
498 * cleaning-up a ua_chan in an error path. Skip the
499 * accounting in this case.
500 */
e38d96f9
MD
501 if (sock >= 0) {
502 save_per_pid_lost_discarded_counters(ua_chan);
c8335706 503 }
7972aab2 504 }
d0b96690 505
edb67388 506 if (ua_chan->obj != NULL) {
d0b96690
DG
507 /* Remove channel from application UST object descriptor. */
508 iter.iter.node = &ua_chan->ust_objd_node.node;
c6e62271
DG
509 ret = lttng_ht_del(app->ust_objd, &iter);
510 assert(!ret);
fb45065e 511 pthread_mutex_lock(&app->sock_lock);
ffe60014 512 ret = ustctl_release_object(sock, ua_chan->obj);
fb45065e 513 pthread_mutex_unlock(&app->sock_lock);
ffe60014
DG
514 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
515 ERR("UST app sock %d release channel obj failed with ret %d",
516 sock, ret);
517 }
7972aab2 518 lttng_fd_put(LTTNG_FD_APPS, 1);
edb67388
DG
519 free(ua_chan->obj);
520 }
36b588ed 521 call_rcu(&ua_chan->rcu_head, delete_ust_app_channel_rcu);
d80a6244
DG
522}
523
fb45065e
MD
524int ust_app_register_done(struct ust_app *app)
525{
526 int ret;
527
528 pthread_mutex_lock(&app->sock_lock);
529 ret = ustctl_register_done(app->sock);
530 pthread_mutex_unlock(&app->sock_lock);
531 return ret;
532}
533
534int ust_app_release_object(struct ust_app *app, struct lttng_ust_object_data *data)
535{
536 int ret, sock;
537
538 if (app) {
539 pthread_mutex_lock(&app->sock_lock);
540 sock = app->sock;
541 } else {
542 sock = -1;
543 }
544 ret = ustctl_release_object(sock, data);
545 if (app) {
546 pthread_mutex_unlock(&app->sock_lock);
547 }
548 return ret;
549}
550
331744e3 551/*
1b532a60
DG
552 * Push metadata to consumer socket.
553 *
dc2bbdae
MD
554 * RCU read-side lock must be held to guarantee existance of socket.
555 * Must be called with the ust app session lock held.
556 * Must be called with the registry lock held.
331744e3
JD
557 *
558 * On success, return the len of metadata pushed or else a negative value.
2c57e06d
MD
559 * Returning a -EPIPE return value means we could not send the metadata,
560 * but it can be caused by recoverable errors (e.g. the application has
561 * terminated concurrently).
331744e3
JD
562 */
563ssize_t ust_app_push_metadata(struct ust_registry_session *registry,
564 struct consumer_socket *socket, int send_zero_data)
565{
566 int ret;
567 char *metadata_str = NULL;
c585821b 568 size_t len, offset, new_metadata_len_sent;
331744e3 569 ssize_t ret_val;
93ec662e 570 uint64_t metadata_key, metadata_version;
331744e3
JD
571
572 assert(registry);
573 assert(socket);
1b532a60 574
c585821b
MD
575 metadata_key = registry->metadata_key;
576
ce34fcd0 577 /*
dc2bbdae
MD
578 * Means that no metadata was assigned to the session. This can
579 * happens if no start has been done previously.
ce34fcd0 580 */
c585821b 581 if (!metadata_key) {
ce34fcd0
MD
582 return 0;
583 }
584
331744e3
JD
585 offset = registry->metadata_len_sent;
586 len = registry->metadata_len - registry->metadata_len_sent;
c585821b 587 new_metadata_len_sent = registry->metadata_len;
93ec662e 588 metadata_version = registry->metadata_version;
331744e3
JD
589 if (len == 0) {
590 DBG3("No metadata to push for metadata key %" PRIu64,
591 registry->metadata_key);
592 ret_val = len;
593 if (send_zero_data) {
594 DBG("No metadata to push");
595 goto push_data;
596 }
597 goto end;
598 }
599
600 /* Allocate only what we have to send. */
601 metadata_str = zmalloc(len);
602 if (!metadata_str) {
603 PERROR("zmalloc ust app metadata string");
604 ret_val = -ENOMEM;
605 goto error;
606 }
c585821b 607 /* Copy what we haven't sent out. */
331744e3 608 memcpy(metadata_str, registry->metadata + offset, len);
331744e3
JD
609
610push_data:
c585821b
MD
611 pthread_mutex_unlock(&registry->lock);
612 /*
613 * We need to unlock the registry while we push metadata to
614 * break a circular dependency between the consumerd metadata
615 * lock and the sessiond registry lock. Indeed, pushing metadata
616 * to the consumerd awaits that it gets pushed all the way to
617 * relayd, but doing so requires grabbing the metadata lock. If
618 * a concurrent metadata request is being performed by
619 * consumerd, this can try to grab the registry lock on the
620 * sessiond while holding the metadata lock on the consumer
621 * daemon. Those push and pull schemes are performed on two
622 * different bidirectionnal communication sockets.
623 */
624 ret = consumer_push_metadata(socket, metadata_key,
93ec662e 625 metadata_str, len, offset, metadata_version);
c585821b 626 pthread_mutex_lock(&registry->lock);
331744e3 627 if (ret < 0) {
000baf6a 628 /*
dc2bbdae
MD
629 * There is an acceptable race here between the registry
630 * metadata key assignment and the creation on the
631 * consumer. The session daemon can concurrently push
632 * metadata for this registry while being created on the
633 * consumer since the metadata key of the registry is
634 * assigned *before* it is setup to avoid the consumer
635 * to ask for metadata that could possibly be not found
636 * in the session daemon.
000baf6a 637 *
dc2bbdae
MD
638 * The metadata will get pushed either by the session
639 * being stopped or the consumer requesting metadata if
640 * that race is triggered.
000baf6a
DG
641 */
642 if (ret == -LTTCOMM_CONSUMERD_CHANNEL_FAIL) {
643 ret = 0;
c585821b
MD
644 } else {
645 ERR("Error pushing metadata to consumer");
000baf6a 646 }
331744e3
JD
647 ret_val = ret;
648 goto error_push;
c585821b
MD
649 } else {
650 /*
651 * Metadata may have been concurrently pushed, since
652 * we're not holding the registry lock while pushing to
653 * consumer. This is handled by the fact that we send
654 * the metadata content, size, and the offset at which
655 * that metadata belongs. This may arrive out of order
656 * on the consumer side, and the consumer is able to
657 * deal with overlapping fragments. The consumer
658 * supports overlapping fragments, which must be
659 * contiguous starting from offset 0. We keep the
660 * largest metadata_len_sent value of the concurrent
661 * send.
662 */
663 registry->metadata_len_sent =
664 max_t(size_t, registry->metadata_len_sent,
665 new_metadata_len_sent);
331744e3 666 }
331744e3
JD
667 free(metadata_str);
668 return len;
669
670end:
671error:
ce34fcd0
MD
672 if (ret_val) {
673 /*
dc2bbdae
MD
674 * On error, flag the registry that the metadata is
675 * closed. We were unable to push anything and this
676 * means that either the consumer is not responding or
677 * the metadata cache has been destroyed on the
678 * consumer.
ce34fcd0
MD
679 */
680 registry->metadata_closed = 1;
681 }
331744e3
JD
682error_push:
683 free(metadata_str);
684 return ret_val;
685}
686
d88aee68 687/*
ce34fcd0 688 * For a given application and session, push metadata to consumer.
331744e3
JD
689 * Either sock or consumer is required : if sock is NULL, the default
690 * socket to send the metadata is retrieved from consumer, if sock
691 * is not NULL we use it to send the metadata.
ce34fcd0 692 * RCU read-side lock must be held while calling this function,
dc2bbdae
MD
693 * therefore ensuring existance of registry. It also ensures existance
694 * of socket throughout this function.
d88aee68
DG
695 *
696 * Return 0 on success else a negative error.
2c57e06d
MD
697 * Returning a -EPIPE return value means we could not send the metadata,
698 * but it can be caused by recoverable errors (e.g. the application has
699 * terminated concurrently).
d88aee68 700 */
7972aab2
DG
701static int push_metadata(struct ust_registry_session *registry,
702 struct consumer_output *consumer)
d88aee68 703{
331744e3
JD
704 int ret_val;
705 ssize_t ret;
d88aee68
DG
706 struct consumer_socket *socket;
707
7972aab2
DG
708 assert(registry);
709 assert(consumer);
710
ce34fcd0 711 pthread_mutex_lock(&registry->lock);
ce34fcd0 712 if (registry->metadata_closed) {
dc2bbdae
MD
713 ret_val = -EPIPE;
714 goto error;
d88aee68
DG
715 }
716
d88aee68 717 /* Get consumer socket to use to push the metadata.*/
7972aab2
DG
718 socket = consumer_find_socket_by_bitness(registry->bits_per_long,
719 consumer);
d88aee68 720 if (!socket) {
331744e3 721 ret_val = -1;
ce34fcd0 722 goto error;
d88aee68
DG
723 }
724
331744e3 725 ret = ust_app_push_metadata(registry, socket, 0);
d88aee68 726 if (ret < 0) {
331744e3 727 ret_val = ret;
ce34fcd0 728 goto error;
d88aee68 729 }
dc2bbdae 730 pthread_mutex_unlock(&registry->lock);
d88aee68
DG
731 return 0;
732
ce34fcd0 733error:
dc2bbdae 734 pthread_mutex_unlock(&registry->lock);
331744e3 735 return ret_val;
d88aee68
DG
736}
737
738/*
739 * Send to the consumer a close metadata command for the given session. Once
740 * done, the metadata channel is deleted and the session metadata pointer is
dc2bbdae 741 * nullified. The session lock MUST be held unless the application is
d88aee68
DG
742 * in the destroy path.
743 *
744 * Return 0 on success else a negative value.
745 */
7972aab2
DG
746static int close_metadata(struct ust_registry_session *registry,
747 struct consumer_output *consumer)
d88aee68
DG
748{
749 int ret;
750 struct consumer_socket *socket;
751
7972aab2
DG
752 assert(registry);
753 assert(consumer);
d88aee68 754
7972aab2
DG
755 rcu_read_lock();
756
ce34fcd0
MD
757 pthread_mutex_lock(&registry->lock);
758
7972aab2 759 if (!registry->metadata_key || registry->metadata_closed) {
d88aee68 760 ret = 0;
1b532a60 761 goto end;
d88aee68
DG
762 }
763
d88aee68 764 /* Get consumer socket to use to push the metadata.*/
7972aab2
DG
765 socket = consumer_find_socket_by_bitness(registry->bits_per_long,
766 consumer);
d88aee68
DG
767 if (!socket) {
768 ret = -1;
7972aab2 769 goto error;
d88aee68
DG
770 }
771
7972aab2 772 ret = consumer_close_metadata(socket, registry->metadata_key);
d88aee68 773 if (ret < 0) {
7972aab2 774 goto error;
d88aee68
DG
775 }
776
d88aee68 777error:
1b532a60
DG
778 /*
779 * Metadata closed. Even on error this means that the consumer is not
780 * responding or not found so either way a second close should NOT be emit
781 * for this registry.
782 */
783 registry->metadata_closed = 1;
784end:
ce34fcd0 785 pthread_mutex_unlock(&registry->lock);
7972aab2 786 rcu_read_unlock();
d88aee68
DG
787 return ret;
788}
789
36b588ed
MD
790/*
791 * We need to execute ht_destroy outside of RCU read-side critical
0b2dc8df
MD
792 * section and outside of call_rcu thread, so we postpone its execution
793 * using ht_cleanup_push. It is simpler than to change the semantic of
794 * the many callers of delete_ust_app_session().
36b588ed
MD
795 */
796static
797void delete_ust_app_session_rcu(struct rcu_head *head)
798{
799 struct ust_app_session *ua_sess =
800 caa_container_of(head, struct ust_app_session, rcu_head);
801
0b2dc8df 802 ht_cleanup_push(ua_sess->channels);
36b588ed
MD
803 free(ua_sess);
804}
805
d80a6244
DG
806/*
807 * Delete ust app session safely. RCU read lock must be held before calling
808 * this function.
82cac6d2
JG
809 *
810 * The session list lock must be held by the caller.
d80a6244 811 */
8b366481 812static
d0b96690
DG
813void delete_ust_app_session(int sock, struct ust_app_session *ua_sess,
814 struct ust_app *app)
d80a6244
DG
815{
816 int ret;
bec39940 817 struct lttng_ht_iter iter;
d80a6244 818 struct ust_app_channel *ua_chan;
7972aab2 819 struct ust_registry_session *registry;
d80a6244 820
d88aee68
DG
821 assert(ua_sess);
822
1b532a60
DG
823 pthread_mutex_lock(&ua_sess->lock);
824
b161602a
MD
825 assert(!ua_sess->deleted);
826 ua_sess->deleted = true;
827
7972aab2 828 registry = get_session_registry(ua_sess);
fad1ed2f 829 /* Registry can be null on error path during initialization. */
ce34fcd0 830 if (registry) {
d88aee68 831 /* Push metadata for application before freeing the application. */
7972aab2 832 (void) push_metadata(registry, ua_sess->consumer);
d88aee68 833
7972aab2
DG
834 /*
835 * Don't ask to close metadata for global per UID buffers. Close
1b532a60
DG
836 * metadata only on destroy trace session in this case. Also, the
837 * previous push metadata could have flag the metadata registry to
838 * close so don't send a close command if closed.
7972aab2 839 */
ce34fcd0 840 if (ua_sess->buffer_type != LTTNG_BUFFER_PER_UID) {
7972aab2
DG
841 /* And ask to close it for this session registry. */
842 (void) close_metadata(registry, ua_sess->consumer);
843 }
d80a6244
DG
844 }
845
bec39940
DG
846 cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
847 node.node) {
848 ret = lttng_ht_del(ua_sess->channels, &iter);
525b0740 849 assert(!ret);
d0b96690 850 delete_ust_app_channel(sock, ua_chan, app);
d80a6244 851 }
d80a6244 852
7972aab2
DG
853 /* In case of per PID, the registry is kept in the session. */
854 if (ua_sess->buffer_type == LTTNG_BUFFER_PER_PID) {
855 struct buffer_reg_pid *reg_pid = buffer_reg_pid_find(ua_sess->id);
856 if (reg_pid) {
fad1ed2f
JR
857 /*
858 * Registry can be null on error path during
859 * initialization.
860 */
7972aab2
DG
861 buffer_reg_pid_remove(reg_pid);
862 buffer_reg_pid_destroy(reg_pid);
863 }
864 }
d0b96690 865
aee6bafd 866 if (ua_sess->handle != -1) {
fb45065e 867 pthread_mutex_lock(&app->sock_lock);
ffe60014 868 ret = ustctl_release_handle(sock, ua_sess->handle);
fb45065e 869 pthread_mutex_unlock(&app->sock_lock);
ffe60014
DG
870 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
871 ERR("UST app sock %d release session handle failed with ret %d",
872 sock, ret);
873 }
10b56aef
MD
874 /* Remove session from application UST object descriptor. */
875 iter.iter.node = &ua_sess->ust_objd_node.node;
876 ret = lttng_ht_del(app->ust_sessions_objd, &iter);
877 assert(!ret);
aee6bafd 878 }
10b56aef 879
1b532a60
DG
880 pthread_mutex_unlock(&ua_sess->lock);
881
6addfa37
MD
882 consumer_output_put(ua_sess->consumer);
883
36b588ed 884 call_rcu(&ua_sess->rcu_head, delete_ust_app_session_rcu);
d80a6244 885}
91d76f53
DG
886
887/*
284d8f55
DG
888 * Delete a traceable application structure from the global list. Never call
889 * this function outside of a call_rcu call.
36b588ed
MD
890 *
891 * RCU read side lock should _NOT_ be held when calling this function.
91d76f53 892 */
8b366481
DG
893static
894void delete_ust_app(struct ust_app *app)
91d76f53 895{
8b366481 896 int ret, sock;
d42f20df 897 struct ust_app_session *ua_sess, *tmp_ua_sess;
44d3bd01 898
82cac6d2
JG
899 /*
900 * The session list lock must be held during this function to guarantee
901 * the existence of ua_sess.
902 */
903 session_lock_list();
d80a6244 904 /* Delete ust app sessions info */
852d0037
DG
905 sock = app->sock;
906 app->sock = -1;
d80a6244 907
8b366481 908 /* Wipe sessions */
d42f20df
DG
909 cds_list_for_each_entry_safe(ua_sess, tmp_ua_sess, &app->teardown_head,
910 teardown_node) {
911 /* Free every object in the session and the session. */
36b588ed 912 rcu_read_lock();
d0b96690 913 delete_ust_app_session(sock, ua_sess, app);
36b588ed 914 rcu_read_unlock();
d80a6244 915 }
36b588ed 916
0b2dc8df 917 ht_cleanup_push(app->sessions);
10b56aef 918 ht_cleanup_push(app->ust_sessions_objd);
0b2dc8df 919 ht_cleanup_push(app->ust_objd);
d80a6244 920
6414a713 921 /*
852d0037
DG
922 * Wait until we have deleted the application from the sock hash table
923 * before closing this socket, otherwise an application could re-use the
924 * socket ID and race with the teardown, using the same hash table entry.
925 *
926 * It's OK to leave the close in call_rcu. We want it to stay unique for
927 * all RCU readers that could run concurrently with unregister app,
928 * therefore we _need_ to only close that socket after a grace period. So
929 * it should stay in this RCU callback.
930 *
931 * This close() is a very important step of the synchronization model so
932 * every modification to this function must be carefully reviewed.
6414a713 933 */
799e2c4f
MD
934 ret = close(sock);
935 if (ret) {
936 PERROR("close");
937 }
4063050c 938 lttng_fd_put(LTTNG_FD_APPS, 1);
d80a6244 939
852d0037 940 DBG2("UST app pid %d deleted", app->pid);
284d8f55 941 free(app);
82cac6d2 942 session_unlock_list();
099e26bd
DG
943}
944
945/*
f6a9efaa 946 * URCU intermediate call to delete an UST app.
099e26bd 947 */
8b366481
DG
948static
949void delete_ust_app_rcu(struct rcu_head *head)
099e26bd 950{
bec39940
DG
951 struct lttng_ht_node_ulong *node =
952 caa_container_of(head, struct lttng_ht_node_ulong, head);
f6a9efaa 953 struct ust_app *app =
852d0037 954 caa_container_of(node, struct ust_app, pid_n);
f6a9efaa 955
852d0037 956 DBG3("Call RCU deleting app PID %d", app->pid);
f6a9efaa 957 delete_ust_app(app);
099e26bd
DG
958}
959
ffe60014
DG
960/*
961 * Delete the session from the application ht and delete the data structure by
962 * freeing every object inside and releasing them.
82cac6d2
JG
963 *
964 * The session list lock must be held by the caller.
ffe60014 965 */
d0b96690 966static void destroy_app_session(struct ust_app *app,
ffe60014
DG
967 struct ust_app_session *ua_sess)
968{
969 int ret;
970 struct lttng_ht_iter iter;
971
972 assert(app);
973 assert(ua_sess);
974
975 iter.iter.node = &ua_sess->node.node;
976 ret = lttng_ht_del(app->sessions, &iter);
977 if (ret) {
978 /* Already scheduled for teardown. */
979 goto end;
980 }
981
982 /* Once deleted, free the data structure. */
d0b96690 983 delete_ust_app_session(app->sock, ua_sess, app);
ffe60014
DG
984
985end:
986 return;
987}
988
8b366481
DG
989/*
990 * Alloc new UST app session.
991 */
992static
40bbd087 993struct ust_app_session *alloc_ust_app_session(void)
8b366481
DG
994{
995 struct ust_app_session *ua_sess;
996
997 /* Init most of the default value by allocating and zeroing */
998 ua_sess = zmalloc(sizeof(struct ust_app_session));
999 if (ua_sess == NULL) {
1000 PERROR("malloc");
ffe60014 1001 goto error_free;
8b366481
DG
1002 }
1003
1004 ua_sess->handle = -1;
bec39940 1005 ua_sess->channels = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
ad7a9107 1006 ua_sess->metadata_attr.type = LTTNG_UST_CHAN_METADATA;
84ad93e8 1007 pthread_mutex_init(&ua_sess->lock, NULL);
ad7a9107 1008
8b366481
DG
1009 return ua_sess;
1010
ffe60014 1011error_free:
8b366481
DG
1012 return NULL;
1013}
1014
1015/*
1016 * Alloc new UST app channel.
1017 */
1018static
1019struct ust_app_channel *alloc_ust_app_channel(char *name,
d0b96690 1020 struct ust_app_session *ua_sess,
ffe60014 1021 struct lttng_ust_channel_attr *attr)
8b366481
DG
1022{
1023 struct ust_app_channel *ua_chan;
1024
1025 /* Init most of the default value by allocating and zeroing */
1026 ua_chan = zmalloc(sizeof(struct ust_app_channel));
1027 if (ua_chan == NULL) {
1028 PERROR("malloc");
1029 goto error;
1030 }
1031
1032 /* Setup channel name */
1033 strncpy(ua_chan->name, name, sizeof(ua_chan->name));
1034 ua_chan->name[sizeof(ua_chan->name) - 1] = '\0';
1035
1036 ua_chan->enabled = 1;
1037 ua_chan->handle = -1;
45893984 1038 ua_chan->session = ua_sess;
ffe60014 1039 ua_chan->key = get_next_channel_key();
bec39940
DG
1040 ua_chan->ctx = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
1041 ua_chan->events = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
1042 lttng_ht_node_init_str(&ua_chan->node, ua_chan->name);
8b366481
DG
1043
1044 CDS_INIT_LIST_HEAD(&ua_chan->streams.head);
31746f93 1045 CDS_INIT_LIST_HEAD(&ua_chan->ctx_list);
8b366481
DG
1046
1047 /* Copy attributes */
1048 if (attr) {
ffe60014 1049 /* Translate from lttng_ust_channel to ustctl_consumer_channel_attr. */
2fe6e7f5
DG
1050 ua_chan->attr.subbuf_size = attr->subbuf_size;
1051 ua_chan->attr.num_subbuf = attr->num_subbuf;
1052 ua_chan->attr.overwrite = attr->overwrite;
1053 ua_chan->attr.switch_timer_interval = attr->switch_timer_interval;
1054 ua_chan->attr.read_timer_interval = attr->read_timer_interval;
1055 ua_chan->attr.output = attr->output;
491d1539 1056 ua_chan->attr.blocking_timeout = attr->u.s.blocking_timeout;
8b366481 1057 }
ffe60014
DG
1058 /* By default, the channel is a per cpu channel. */
1059 ua_chan->attr.type = LTTNG_UST_CHAN_PER_CPU;
8b366481
DG
1060
1061 DBG3("UST app channel %s allocated", ua_chan->name);
1062
1063 return ua_chan;
1064
1065error:
1066 return NULL;
1067}
1068
37f1c236
DG
1069/*
1070 * Allocate and initialize a UST app stream.
1071 *
1072 * Return newly allocated stream pointer or NULL on error.
1073 */
ffe60014 1074struct ust_app_stream *ust_app_alloc_stream(void)
37f1c236
DG
1075{
1076 struct ust_app_stream *stream = NULL;
1077
1078 stream = zmalloc(sizeof(*stream));
1079 if (stream == NULL) {
1080 PERROR("zmalloc ust app stream");
1081 goto error;
1082 }
1083
1084 /* Zero could be a valid value for a handle so flag it to -1. */
1085 stream->handle = -1;
1086
1087error:
1088 return stream;
1089}
1090
8b366481
DG
1091/*
1092 * Alloc new UST app event.
1093 */
1094static
1095struct ust_app_event *alloc_ust_app_event(char *name,
1096 struct lttng_ust_event *attr)
1097{
1098 struct ust_app_event *ua_event;
1099
1100 /* Init most of the default value by allocating and zeroing */
1101 ua_event = zmalloc(sizeof(struct ust_app_event));
1102 if (ua_event == NULL) {
1103 PERROR("malloc");
1104 goto error;
1105 }
1106
1107 ua_event->enabled = 1;
1108 strncpy(ua_event->name, name, sizeof(ua_event->name));
1109 ua_event->name[sizeof(ua_event->name) - 1] = '\0';
bec39940 1110 lttng_ht_node_init_str(&ua_event->node, ua_event->name);
8b366481
DG
1111
1112 /* Copy attributes */
1113 if (attr) {
1114 memcpy(&ua_event->attr, attr, sizeof(ua_event->attr));
1115 }
1116
1117 DBG3("UST app event %s allocated", ua_event->name);
1118
1119 return ua_event;
1120
1121error:
1122 return NULL;
1123}
1124
1125/*
1126 * Alloc new UST app context.
1127 */
1128static
bdf64013 1129struct ust_app_ctx *alloc_ust_app_ctx(struct lttng_ust_context_attr *uctx)
8b366481
DG
1130{
1131 struct ust_app_ctx *ua_ctx;
1132
1133 ua_ctx = zmalloc(sizeof(struct ust_app_ctx));
1134 if (ua_ctx == NULL) {
1135 goto error;
1136 }
1137
31746f93
DG
1138 CDS_INIT_LIST_HEAD(&ua_ctx->list);
1139
8b366481
DG
1140 if (uctx) {
1141 memcpy(&ua_ctx->ctx, uctx, sizeof(ua_ctx->ctx));
bdf64013
JG
1142 if (uctx->ctx == LTTNG_UST_CONTEXT_APP_CONTEXT) {
1143 char *provider_name = NULL, *ctx_name = NULL;
1144
1145 provider_name = strdup(uctx->u.app_ctx.provider_name);
1146 ctx_name = strdup(uctx->u.app_ctx.ctx_name);
1147 if (!provider_name || !ctx_name) {
1148 free(provider_name);
1149 free(ctx_name);
1150 goto error;
1151 }
1152
1153 ua_ctx->ctx.u.app_ctx.provider_name = provider_name;
1154 ua_ctx->ctx.u.app_ctx.ctx_name = ctx_name;
1155 }
8b366481
DG
1156 }
1157
1158 DBG3("UST app context %d allocated", ua_ctx->ctx.ctx);
8b366481 1159 return ua_ctx;
bdf64013
JG
1160error:
1161 free(ua_ctx);
1162 return NULL;
8b366481
DG
1163}
1164
025faf73
DG
1165/*
1166 * Allocate a filter and copy the given original filter.
1167 *
1168 * Return allocated filter or NULL on error.
1169 */
51755dc8
JG
1170static struct lttng_filter_bytecode *copy_filter_bytecode(
1171 struct lttng_filter_bytecode *orig_f)
025faf73 1172{
51755dc8 1173 struct lttng_filter_bytecode *filter = NULL;
025faf73
DG
1174
1175 /* Copy filter bytecode */
1176 filter = zmalloc(sizeof(*filter) + orig_f->len);
1177 if (!filter) {
51755dc8 1178 PERROR("zmalloc alloc filter bytecode");
025faf73
DG
1179 goto error;
1180 }
1181
1182 memcpy(filter, orig_f, sizeof(*filter) + orig_f->len);
1183
1184error:
1185 return filter;
1186}
1187
51755dc8
JG
1188/*
1189 * Create a liblttng-ust filter bytecode from given bytecode.
1190 *
1191 * Return allocated filter or NULL on error.
1192 */
1193static struct lttng_ust_filter_bytecode *create_ust_bytecode_from_bytecode(
1194 struct lttng_filter_bytecode *orig_f)
1195{
1196 struct lttng_ust_filter_bytecode *filter = NULL;
1197
1198 /* Copy filter bytecode */
1199 filter = zmalloc(sizeof(*filter) + orig_f->len);
1200 if (!filter) {
1201 PERROR("zmalloc alloc ust filter bytecode");
1202 goto error;
1203 }
1204
1205 assert(sizeof(struct lttng_filter_bytecode) ==
1206 sizeof(struct lttng_ust_filter_bytecode));
1207 memcpy(filter, orig_f, sizeof(*filter) + orig_f->len);
1208error:
1209 return filter;
1210}
1211
099e26bd 1212/*
421cb601
DG
1213 * Find an ust_app using the sock and return it. RCU read side lock must be
1214 * held before calling this helper function.
099e26bd 1215 */
f20baf8e 1216struct ust_app *ust_app_find_by_sock(int sock)
099e26bd 1217{
bec39940 1218 struct lttng_ht_node_ulong *node;
bec39940 1219 struct lttng_ht_iter iter;
f6a9efaa 1220
852d0037 1221 lttng_ht_lookup(ust_app_ht_by_sock, (void *)((unsigned long) sock), &iter);
bec39940 1222 node = lttng_ht_iter_get_node_ulong(&iter);
f6a9efaa
DG
1223 if (node == NULL) {
1224 DBG2("UST app find by sock %d not found", sock);
f6a9efaa
DG
1225 goto error;
1226 }
852d0037
DG
1227
1228 return caa_container_of(node, struct ust_app, sock_n);
f6a9efaa
DG
1229
1230error:
1231 return NULL;
099e26bd
DG
1232}
1233
d0b96690
DG
1234/*
1235 * Find an ust_app using the notify sock and return it. RCU read side lock must
1236 * be held before calling this helper function.
1237 */
1238static struct ust_app *find_app_by_notify_sock(int sock)
1239{
1240 struct lttng_ht_node_ulong *node;
1241 struct lttng_ht_iter iter;
1242
1243 lttng_ht_lookup(ust_app_ht_by_notify_sock, (void *)((unsigned long) sock),
1244 &iter);
1245 node = lttng_ht_iter_get_node_ulong(&iter);
1246 if (node == NULL) {
1247 DBG2("UST app find by notify sock %d not found", sock);
1248 goto error;
1249 }
1250
1251 return caa_container_of(node, struct ust_app, notify_sock_n);
1252
1253error:
1254 return NULL;
1255}
1256
025faf73
DG
1257/*
1258 * Lookup for an ust app event based on event name, filter bytecode and the
1259 * event loglevel.
1260 *
1261 * Return an ust_app_event object or NULL on error.
1262 */
18eace3b 1263static struct ust_app_event *find_ust_app_event(struct lttng_ht *ht,
88e3c2f5 1264 const char *name, const struct lttng_filter_bytecode *filter,
2106efa0 1265 int loglevel_value,
39c5a3a7 1266 const struct lttng_event_exclusion *exclusion)
18eace3b
DG
1267{
1268 struct lttng_ht_iter iter;
1269 struct lttng_ht_node_str *node;
1270 struct ust_app_event *event = NULL;
1271 struct ust_app_ht_key key;
18eace3b
DG
1272
1273 assert(name);
1274 assert(ht);
1275
1276 /* Setup key for event lookup. */
1277 key.name = name;
1278 key.filter = filter;
2106efa0 1279 key.loglevel_type = loglevel_value;
39c5a3a7 1280 /* lttng_event_exclusion and lttng_ust_event_exclusion structures are similar */
51755dc8 1281 key.exclusion = exclusion;
18eace3b 1282
025faf73
DG
1283 /* Lookup using the event name as hash and a custom match fct. */
1284 cds_lfht_lookup(ht->ht, ht->hash_fct((void *) name, lttng_ht_seed),
1285 ht_match_ust_app_event, &key, &iter.iter);
18eace3b
DG
1286 node = lttng_ht_iter_get_node_str(&iter);
1287 if (node == NULL) {
1288 goto end;
1289 }
1290
1291 event = caa_container_of(node, struct ust_app_event, node);
1292
1293end:
18eace3b
DG
1294 return event;
1295}
1296
55cc08a6
DG
1297/*
1298 * Create the channel context on the tracer.
d0b96690
DG
1299 *
1300 * Called with UST app session lock held.
55cc08a6
DG
1301 */
1302static
1303int create_ust_channel_context(struct ust_app_channel *ua_chan,
1304 struct ust_app_ctx *ua_ctx, struct ust_app *app)
1305{
1306 int ret;
1307
840cb59c 1308 health_code_update();
86acf0da 1309
fb45065e 1310 pthread_mutex_lock(&app->sock_lock);
852d0037 1311 ret = ustctl_add_context(app->sock, &ua_ctx->ctx,
55cc08a6 1312 ua_chan->obj, &ua_ctx->obj);
fb45065e 1313 pthread_mutex_unlock(&app->sock_lock);
55cc08a6 1314 if (ret < 0) {
ffe60014
DG
1315 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1316 ERR("UST app create channel context failed for app (pid: %d) "
1317 "with ret %d", app->pid, ret);
1318 } else {
3757b385
DG
1319 /*
1320 * This is normal behavior, an application can die during the
1321 * creation process. Don't report an error so the execution can
1322 * continue normally.
1323 */
1324 ret = 0;
88e3c2f5 1325 DBG3("UST app add context failed. Application is dead.");
ffe60014 1326 }
55cc08a6
DG
1327 goto error;
1328 }
1329
1330 ua_ctx->handle = ua_ctx->obj->handle;
1331
d0b96690
DG
1332 DBG2("UST app context handle %d created successfully for channel %s",
1333 ua_ctx->handle, ua_chan->name);
55cc08a6
DG
1334
1335error:
840cb59c 1336 health_code_update();
55cc08a6
DG
1337 return ret;
1338}
1339
53a80697
MD
1340/*
1341 * Set the filter on the tracer.
1342 */
1343static
1344int set_ust_event_filter(struct ust_app_event *ua_event,
1345 struct ust_app *app)
1346{
1347 int ret;
51755dc8 1348 struct lttng_ust_filter_bytecode *ust_bytecode = NULL;
53a80697 1349
840cb59c 1350 health_code_update();
86acf0da 1351
53a80697 1352 if (!ua_event->filter) {
86acf0da
DG
1353 ret = 0;
1354 goto error;
53a80697
MD
1355 }
1356
51755dc8
JG
1357 ust_bytecode = create_ust_bytecode_from_bytecode(ua_event->filter);
1358 if (!ust_bytecode) {
1359 ret = -LTTNG_ERR_NOMEM;
1360 goto error;
1361 }
fb45065e 1362 pthread_mutex_lock(&app->sock_lock);
51755dc8 1363 ret = ustctl_set_filter(app->sock, ust_bytecode,
53a80697 1364 ua_event->obj);
fb45065e 1365 pthread_mutex_unlock(&app->sock_lock);
53a80697 1366 if (ret < 0) {
ffe60014
DG
1367 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1368 ERR("UST app event %s filter failed for app (pid: %d) "
1369 "with ret %d", ua_event->attr.name, app->pid, ret);
1370 } else {
3757b385
DG
1371 /*
1372 * This is normal behavior, an application can die during the
1373 * creation process. Don't report an error so the execution can
1374 * continue normally.
1375 */
1376 ret = 0;
ffe60014
DG
1377 DBG3("UST app filter event failed. Application is dead.");
1378 }
53a80697
MD
1379 goto error;
1380 }
1381
1382 DBG2("UST filter set successfully for event %s", ua_event->name);
1383
1384error:
840cb59c 1385 health_code_update();
51755dc8 1386 free(ust_bytecode);
53a80697
MD
1387 return ret;
1388}
1389
51755dc8
JG
1390static
1391struct lttng_ust_event_exclusion *create_ust_exclusion_from_exclusion(
1392 struct lttng_event_exclusion *exclusion)
1393{
1394 struct lttng_ust_event_exclusion *ust_exclusion = NULL;
1395 size_t exclusion_alloc_size = sizeof(struct lttng_ust_event_exclusion) +
1396 LTTNG_UST_SYM_NAME_LEN * exclusion->count;
1397
1398 ust_exclusion = zmalloc(exclusion_alloc_size);
1399 if (!ust_exclusion) {
1400 PERROR("malloc");
1401 goto end;
1402 }
1403
1404 assert(sizeof(struct lttng_event_exclusion) ==
1405 sizeof(struct lttng_ust_event_exclusion));
1406 memcpy(ust_exclusion, exclusion, exclusion_alloc_size);
1407end:
1408 return ust_exclusion;
1409}
1410
7cc9a73c
JI
1411/*
1412 * Set event exclusions on the tracer.
1413 */
1414static
1415int set_ust_event_exclusion(struct ust_app_event *ua_event,
1416 struct ust_app *app)
1417{
1418 int ret;
51755dc8 1419 struct lttng_ust_event_exclusion *ust_exclusion = NULL;
7cc9a73c
JI
1420
1421 health_code_update();
1422
1423 if (!ua_event->exclusion || !ua_event->exclusion->count) {
1424 ret = 0;
1425 goto error;
1426 }
1427
51755dc8
JG
1428 ust_exclusion = create_ust_exclusion_from_exclusion(
1429 ua_event->exclusion);
1430 if (!ust_exclusion) {
1431 ret = -LTTNG_ERR_NOMEM;
1432 goto error;
1433 }
fb45065e 1434 pthread_mutex_lock(&app->sock_lock);
51755dc8 1435 ret = ustctl_set_exclusion(app->sock, ust_exclusion, ua_event->obj);
fb45065e 1436 pthread_mutex_unlock(&app->sock_lock);
7cc9a73c
JI
1437 if (ret < 0) {
1438 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1439 ERR("UST app event %s exclusions failed for app (pid: %d) "
1440 "with ret %d", ua_event->attr.name, app->pid, ret);
1441 } else {
1442 /*
1443 * This is normal behavior, an application can die during the
1444 * creation process. Don't report an error so the execution can
1445 * continue normally.
1446 */
1447 ret = 0;
1448 DBG3("UST app event exclusion failed. Application is dead.");
1449 }
1450 goto error;
1451 }
1452
1453 DBG2("UST exclusion set successfully for event %s", ua_event->name);
1454
1455error:
1456 health_code_update();
51755dc8 1457 free(ust_exclusion);
7cc9a73c
JI
1458 return ret;
1459}
1460
9730260e
DG
1461/*
1462 * Disable the specified event on to UST tracer for the UST session.
1463 */
1464static int disable_ust_event(struct ust_app *app,
1465 struct ust_app_session *ua_sess, struct ust_app_event *ua_event)
1466{
1467 int ret;
1468
840cb59c 1469 health_code_update();
86acf0da 1470
fb45065e 1471 pthread_mutex_lock(&app->sock_lock);
852d0037 1472 ret = ustctl_disable(app->sock, ua_event->obj);
fb45065e 1473 pthread_mutex_unlock(&app->sock_lock);
9730260e 1474 if (ret < 0) {
ffe60014
DG
1475 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1476 ERR("UST app event %s disable failed for app (pid: %d) "
1477 "and session handle %d with ret %d",
1478 ua_event->attr.name, app->pid, ua_sess->handle, ret);
1479 } else {
3757b385
DG
1480 /*
1481 * This is normal behavior, an application can die during the
1482 * creation process. Don't report an error so the execution can
1483 * continue normally.
1484 */
1485 ret = 0;
ffe60014
DG
1486 DBG3("UST app disable event failed. Application is dead.");
1487 }
9730260e
DG
1488 goto error;
1489 }
1490
1491 DBG2("UST app event %s disabled successfully for app (pid: %d)",
852d0037 1492 ua_event->attr.name, app->pid);
9730260e
DG
1493
1494error:
840cb59c 1495 health_code_update();
9730260e
DG
1496 return ret;
1497}
1498
78f0bacd
DG
1499/*
1500 * Disable the specified channel on to UST tracer for the UST session.
1501 */
1502static int disable_ust_channel(struct ust_app *app,
1503 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
1504{
1505 int ret;
1506
840cb59c 1507 health_code_update();
86acf0da 1508
fb45065e 1509 pthread_mutex_lock(&app->sock_lock);
852d0037 1510 ret = ustctl_disable(app->sock, ua_chan->obj);
fb45065e 1511 pthread_mutex_unlock(&app->sock_lock);
78f0bacd 1512 if (ret < 0) {
ffe60014
DG
1513 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1514 ERR("UST app channel %s disable failed for app (pid: %d) "
1515 "and session handle %d with ret %d",
1516 ua_chan->name, app->pid, ua_sess->handle, ret);
1517 } else {
3757b385
DG
1518 /*
1519 * This is normal behavior, an application can die during the
1520 * creation process. Don't report an error so the execution can
1521 * continue normally.
1522 */
1523 ret = 0;
ffe60014
DG
1524 DBG3("UST app disable channel failed. Application is dead.");
1525 }
78f0bacd
DG
1526 goto error;
1527 }
1528
78f0bacd 1529 DBG2("UST app channel %s disabled successfully for app (pid: %d)",
852d0037 1530 ua_chan->name, app->pid);
78f0bacd
DG
1531
1532error:
840cb59c 1533 health_code_update();
78f0bacd
DG
1534 return ret;
1535}
1536
1537/*
1538 * Enable the specified channel on to UST tracer for the UST session.
1539 */
1540static int enable_ust_channel(struct ust_app *app,
1541 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
1542{
1543 int ret;
1544
840cb59c 1545 health_code_update();
86acf0da 1546
fb45065e 1547 pthread_mutex_lock(&app->sock_lock);
852d0037 1548 ret = ustctl_enable(app->sock, ua_chan->obj);
fb45065e 1549 pthread_mutex_unlock(&app->sock_lock);
78f0bacd 1550 if (ret < 0) {
ffe60014
DG
1551 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1552 ERR("UST app channel %s enable failed for app (pid: %d) "
1553 "and session handle %d with ret %d",
1554 ua_chan->name, app->pid, ua_sess->handle, ret);
1555 } else {
3757b385
DG
1556 /*
1557 * This is normal behavior, an application can die during the
1558 * creation process. Don't report an error so the execution can
1559 * continue normally.
1560 */
1561 ret = 0;
ffe60014
DG
1562 DBG3("UST app enable channel failed. Application is dead.");
1563 }
78f0bacd
DG
1564 goto error;
1565 }
1566
1567 ua_chan->enabled = 1;
1568
1569 DBG2("UST app channel %s enabled successfully for app (pid: %d)",
852d0037 1570 ua_chan->name, app->pid);
78f0bacd
DG
1571
1572error:
840cb59c 1573 health_code_update();
78f0bacd
DG
1574 return ret;
1575}
1576
edb67388
DG
1577/*
1578 * Enable the specified event on to UST tracer for the UST session.
1579 */
1580static int enable_ust_event(struct ust_app *app,
1581 struct ust_app_session *ua_sess, struct ust_app_event *ua_event)
1582{
1583 int ret;
1584
840cb59c 1585 health_code_update();
86acf0da 1586
fb45065e 1587 pthread_mutex_lock(&app->sock_lock);
852d0037 1588 ret = ustctl_enable(app->sock, ua_event->obj);
fb45065e 1589 pthread_mutex_unlock(&app->sock_lock);
edb67388 1590 if (ret < 0) {
ffe60014
DG
1591 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1592 ERR("UST app event %s enable failed for app (pid: %d) "
1593 "and session handle %d with ret %d",
1594 ua_event->attr.name, app->pid, ua_sess->handle, ret);
1595 } else {
3757b385
DG
1596 /*
1597 * This is normal behavior, an application can die during the
1598 * creation process. Don't report an error so the execution can
1599 * continue normally.
1600 */
1601 ret = 0;
ffe60014
DG
1602 DBG3("UST app enable event failed. Application is dead.");
1603 }
edb67388
DG
1604 goto error;
1605 }
1606
1607 DBG2("UST app event %s enabled successfully for app (pid: %d)",
852d0037 1608 ua_event->attr.name, app->pid);
edb67388
DG
1609
1610error:
840cb59c 1611 health_code_update();
edb67388
DG
1612 return ret;
1613}
1614
099e26bd 1615/*
7972aab2 1616 * Send channel and stream buffer to application.
4f3ab6ee 1617 *
ffe60014 1618 * Return 0 on success. On error, a negative value is returned.
4f3ab6ee 1619 */
7972aab2
DG
1620static int send_channel_pid_to_ust(struct ust_app *app,
1621 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
4f3ab6ee
DG
1622{
1623 int ret;
ffe60014 1624 struct ust_app_stream *stream, *stmp;
4f3ab6ee
DG
1625
1626 assert(app);
ffe60014 1627 assert(ua_sess);
4f3ab6ee 1628 assert(ua_chan);
4f3ab6ee 1629
840cb59c 1630 health_code_update();
4f3ab6ee 1631
7972aab2
DG
1632 DBG("UST app sending channel %s to UST app sock %d", ua_chan->name,
1633 app->sock);
86acf0da 1634
ffe60014
DG
1635 /* Send channel to the application. */
1636 ret = ust_consumer_send_channel_to_ust(app, ua_sess, ua_chan);
a7169585
MD
1637 if (ret == -EPIPE || ret == -LTTNG_UST_ERR_EXITING) {
1638 ret = -ENOTCONN; /* Caused by app exiting. */
1639 goto error;
1640 } else if (ret < 0) {
b551a063
DG
1641 goto error;
1642 }
1643
d88aee68
DG
1644 health_code_update();
1645
ffe60014
DG
1646 /* Send all streams to application. */
1647 cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
1648 ret = ust_consumer_send_stream_to_ust(app, ua_chan, stream);
a7169585
MD
1649 if (ret == -EPIPE || ret == -LTTNG_UST_ERR_EXITING) {
1650 ret = -ENOTCONN; /* Caused by app exiting. */
1651 goto error;
1652 } else if (ret < 0) {
ffe60014
DG
1653 goto error;
1654 }
1655 /* We don't need the stream anymore once sent to the tracer. */
1656 cds_list_del(&stream->list);
fb45065e 1657 delete_ust_app_stream(-1, stream, app);
ffe60014 1658 }
ffe60014
DG
1659 /* Flag the channel that it is sent to the application. */
1660 ua_chan->is_sent = 1;
ffe60014 1661
b551a063 1662error:
840cb59c 1663 health_code_update();
b551a063
DG
1664 return ret;
1665}
1666
91d76f53 1667/*
5b4a0ec0 1668 * Create the specified event onto the UST tracer for a UST session.
d0b96690
DG
1669 *
1670 * Should be called with session mutex held.
91d76f53 1671 */
edb67388
DG
1672static
1673int create_ust_event(struct ust_app *app, struct ust_app_session *ua_sess,
1674 struct ust_app_channel *ua_chan, struct ust_app_event *ua_event)
91d76f53 1675{
5b4a0ec0 1676 int ret = 0;
284d8f55 1677
840cb59c 1678 health_code_update();
86acf0da 1679
5b4a0ec0 1680 /* Create UST event on tracer */
fb45065e 1681 pthread_mutex_lock(&app->sock_lock);
852d0037 1682 ret = ustctl_create_event(app->sock, &ua_event->attr, ua_chan->obj,
5b4a0ec0 1683 &ua_event->obj);
fb45065e 1684 pthread_mutex_unlock(&app->sock_lock);
5b4a0ec0 1685 if (ret < 0) {
ffe60014 1686 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
88e3c2f5 1687 abort();
ffe60014
DG
1688 ERR("Error ustctl create event %s for app pid: %d with ret %d",
1689 ua_event->attr.name, app->pid, ret);
1690 } else {
3757b385
DG
1691 /*
1692 * This is normal behavior, an application can die during the
1693 * creation process. Don't report an error so the execution can
1694 * continue normally.
1695 */
1696 ret = 0;
ffe60014
DG
1697 DBG3("UST app create event failed. Application is dead.");
1698 }
5b4a0ec0 1699 goto error;
91d76f53 1700 }
f6a9efaa 1701
5b4a0ec0 1702 ua_event->handle = ua_event->obj->handle;
284d8f55 1703
5b4a0ec0 1704 DBG2("UST app event %s created successfully for pid:%d",
852d0037 1705 ua_event->attr.name, app->pid);
f6a9efaa 1706
840cb59c 1707 health_code_update();
86acf0da 1708
025faf73
DG
1709 /* Set filter if one is present. */
1710 if (ua_event->filter) {
1711 ret = set_ust_event_filter(ua_event, app);
1712 if (ret < 0) {
1713 goto error;
1714 }
1715 }
1716
7cc9a73c
JI
1717 /* Set exclusions for the event */
1718 if (ua_event->exclusion) {
1719 ret = set_ust_event_exclusion(ua_event, app);
1720 if (ret < 0) {
1721 goto error;
1722 }
1723 }
1724
8535a6d9 1725 /* If event not enabled, disable it on the tracer */
40113787
MD
1726 if (ua_event->enabled) {
1727 /*
1728 * We now need to explicitly enable the event, since it
1729 * is now disabled at creation.
1730 */
1731 ret = enable_ust_event(app, ua_sess, ua_event);
1732 if (ret < 0) {
1733 /*
1734 * If we hit an EPERM, something is wrong with our enable call. If
1735 * we get an EEXIST, there is a problem on the tracer side since we
1736 * just created it.
1737 */
1738 switch (ret) {
1739 case -LTTNG_UST_ERR_PERM:
1740 /* Code flow problem */
1741 assert(0);
1742 case -LTTNG_UST_ERR_EXIST:
1743 /* It's OK for our use case. */
1744 ret = 0;
1745 break;
1746 default:
1747 break;
1748 }
1749 goto error;
1750 }
8535a6d9
DG
1751 }
1752
5b4a0ec0 1753error:
840cb59c 1754 health_code_update();
5b4a0ec0 1755 return ret;
91d76f53 1756}
48842b30 1757
5b4a0ec0
DG
1758/*
1759 * Copy data between an UST app event and a LTT event.
1760 */
421cb601 1761static void shadow_copy_event(struct ust_app_event *ua_event,
48842b30
DG
1762 struct ltt_ust_event *uevent)
1763{
b4ffad32
JI
1764 size_t exclusion_alloc_size;
1765
48842b30
DG
1766 strncpy(ua_event->name, uevent->attr.name, sizeof(ua_event->name));
1767 ua_event->name[sizeof(ua_event->name) - 1] = '\0';
1768
fc34caaa
DG
1769 ua_event->enabled = uevent->enabled;
1770
5b4a0ec0
DG
1771 /* Copy event attributes */
1772 memcpy(&ua_event->attr, &uevent->attr, sizeof(ua_event->attr));
1773
53a80697
MD
1774 /* Copy filter bytecode */
1775 if (uevent->filter) {
51755dc8 1776 ua_event->filter = copy_filter_bytecode(uevent->filter);
025faf73 1777 /* Filter might be NULL here in case of ENONEM. */
53a80697 1778 }
b4ffad32
JI
1779
1780 /* Copy exclusion data */
1781 if (uevent->exclusion) {
51755dc8 1782 exclusion_alloc_size = sizeof(struct lttng_event_exclusion) +
b4ffad32
JI
1783 LTTNG_UST_SYM_NAME_LEN * uevent->exclusion->count;
1784 ua_event->exclusion = zmalloc(exclusion_alloc_size);
5f8df26c
JI
1785 if (ua_event->exclusion == NULL) {
1786 PERROR("malloc");
1787 } else {
1788 memcpy(ua_event->exclusion, uevent->exclusion,
1789 exclusion_alloc_size);
b4ffad32
JI
1790 }
1791 }
48842b30
DG
1792}
1793
5b4a0ec0
DG
1794/*
1795 * Copy data between an UST app channel and a LTT channel.
1796 */
421cb601 1797static void shadow_copy_channel(struct ust_app_channel *ua_chan,
48842b30
DG
1798 struct ltt_ust_channel *uchan)
1799{
fc34caaa 1800 DBG2("UST app shadow copy of channel %s started", ua_chan->name);
48842b30
DG
1801
1802 strncpy(ua_chan->name, uchan->name, sizeof(ua_chan->name));
1803 ua_chan->name[sizeof(ua_chan->name) - 1] = '\0';
ffe60014 1804
1624d5b7
JD
1805 ua_chan->tracefile_size = uchan->tracefile_size;
1806 ua_chan->tracefile_count = uchan->tracefile_count;
1807
ffe60014
DG
1808 /* Copy event attributes since the layout is different. */
1809 ua_chan->attr.subbuf_size = uchan->attr.subbuf_size;
1810 ua_chan->attr.num_subbuf = uchan->attr.num_subbuf;
1811 ua_chan->attr.overwrite = uchan->attr.overwrite;
1812 ua_chan->attr.switch_timer_interval = uchan->attr.switch_timer_interval;
1813 ua_chan->attr.read_timer_interval = uchan->attr.read_timer_interval;
e9404c27 1814 ua_chan->monitor_timer_interval = uchan->monitor_timer_interval;
ffe60014 1815 ua_chan->attr.output = uchan->attr.output;
491d1539
MD
1816 ua_chan->attr.blocking_timeout = uchan->attr.u.s.blocking_timeout;
1817
ffe60014
DG
1818 /*
1819 * Note that the attribute channel type is not set since the channel on the
1820 * tracing registry side does not have this information.
1821 */
48842b30 1822
fc34caaa 1823 ua_chan->enabled = uchan->enabled;
7972aab2 1824 ua_chan->tracing_channel_id = uchan->id;
fc34caaa 1825
fc34caaa 1826 DBG3("UST app shadow copy of channel %s done", ua_chan->name);
48842b30
DG
1827}
1828
5b4a0ec0
DG
1829/*
1830 * Copy data between a UST app session and a regular LTT session.
1831 */
421cb601 1832static void shadow_copy_session(struct ust_app_session *ua_sess,
bec39940 1833 struct ltt_ust_session *usess, struct ust_app *app)
48842b30 1834{
477d7741
MD
1835 struct tm *timeinfo;
1836 char datetime[16];
1837 int ret;
d7ba1388 1838 char tmp_shm_path[PATH_MAX];
477d7741 1839
940c4592 1840 timeinfo = localtime(&app->registration_time);
477d7741 1841 strftime(datetime, sizeof(datetime), "%Y%m%d-%H%M%S", timeinfo);
48842b30 1842
421cb601 1843 DBG2("Shadow copy of session handle %d", ua_sess->handle);
48842b30 1844
7972aab2
DG
1845 ua_sess->tracing_id = usess->id;
1846 ua_sess->id = get_next_session_id();
470cc211
JG
1847 ua_sess->real_credentials.uid = app->uid;
1848 ua_sess->real_credentials.gid = app->gid;
1849 ua_sess->effective_credentials.uid = usess->uid;
1850 ua_sess->effective_credentials.gid = usess->gid;
7972aab2
DG
1851 ua_sess->buffer_type = usess->buffer_type;
1852 ua_sess->bits_per_long = app->bits_per_long;
6addfa37 1853
7972aab2 1854 /* There is only one consumer object per session possible. */
6addfa37 1855 consumer_output_get(usess->consumer);
7972aab2 1856 ua_sess->consumer = usess->consumer;
6addfa37 1857
2bba9e53 1858 ua_sess->output_traces = usess->output_traces;
ecc48a90 1859 ua_sess->live_timer_interval = usess->live_timer_interval;
84ad93e8
DG
1860 copy_channel_attr_to_ustctl(&ua_sess->metadata_attr,
1861 &usess->metadata_attr);
7972aab2
DG
1862
1863 switch (ua_sess->buffer_type) {
1864 case LTTNG_BUFFER_PER_PID:
1865 ret = snprintf(ua_sess->path, sizeof(ua_sess->path),
dec56f6c 1866 DEFAULT_UST_TRACE_PID_PATH "/%s-%d-%s", app->name, app->pid,
7972aab2
DG
1867 datetime);
1868 break;
1869 case LTTNG_BUFFER_PER_UID:
1870 ret = snprintf(ua_sess->path, sizeof(ua_sess->path),
470cc211
JG
1871 DEFAULT_UST_TRACE_UID_PATH,
1872 ua_sess->real_credentials.uid,
1873 app->bits_per_long);
7972aab2
DG
1874 break;
1875 default:
1876 assert(0);
1877 goto error;
1878 }
477d7741
MD
1879 if (ret < 0) {
1880 PERROR("asprintf UST shadow copy session");
477d7741 1881 assert(0);
7972aab2 1882 goto error;
477d7741
MD
1883 }
1884
3d071855
MD
1885 strncpy(ua_sess->root_shm_path, usess->root_shm_path,
1886 sizeof(ua_sess->root_shm_path));
1887 ua_sess->root_shm_path[sizeof(ua_sess->root_shm_path) - 1] = '\0';
d7ba1388
MD
1888 strncpy(ua_sess->shm_path, usess->shm_path,
1889 sizeof(ua_sess->shm_path));
1890 ua_sess->shm_path[sizeof(ua_sess->shm_path) - 1] = '\0';
1891 if (ua_sess->shm_path[0]) {
1892 switch (ua_sess->buffer_type) {
1893 case LTTNG_BUFFER_PER_PID:
1894 ret = snprintf(tmp_shm_path, sizeof(tmp_shm_path),
1895 DEFAULT_UST_TRACE_PID_PATH "/%s-%d-%s",
1896 app->name, app->pid, datetime);
1897 break;
1898 case LTTNG_BUFFER_PER_UID:
1899 ret = snprintf(tmp_shm_path, sizeof(tmp_shm_path),
1900 DEFAULT_UST_TRACE_UID_PATH,
1901 app->uid, app->bits_per_long);
1902 break;
1903 default:
1904 assert(0);
1905 goto error;
1906 }
1907 if (ret < 0) {
1908 PERROR("sprintf UST shadow copy session");
1909 assert(0);
1910 goto error;
1911 }
1912 strncat(ua_sess->shm_path, tmp_shm_path,
1913 sizeof(ua_sess->shm_path) - strlen(ua_sess->shm_path) - 1);
1914 ua_sess->shm_path[sizeof(ua_sess->shm_path) - 1] = '\0';
1915 }
6addfa37 1916 return;
7972aab2
DG
1917
1918error:
6addfa37 1919 consumer_output_put(ua_sess->consumer);
48842b30
DG
1920}
1921
78f0bacd
DG
1922/*
1923 * Lookup sesison wrapper.
1924 */
84cd17c6 1925static
fb9a95c4 1926void __lookup_session_by_app(const struct ltt_ust_session *usess,
bec39940 1927 struct ust_app *app, struct lttng_ht_iter *iter)
84cd17c6
MD
1928{
1929 /* Get right UST app session from app */
d9bf3ca4 1930 lttng_ht_lookup(app->sessions, &usess->id, iter);
84cd17c6
MD
1931}
1932
421cb601
DG
1933/*
1934 * Return ust app session from the app session hashtable using the UST session
a991f516 1935 * id.
421cb601 1936 */
48842b30 1937static struct ust_app_session *lookup_session_by_app(
fb9a95c4 1938 const struct ltt_ust_session *usess, struct ust_app *app)
48842b30 1939{
bec39940 1940 struct lttng_ht_iter iter;
d9bf3ca4 1941 struct lttng_ht_node_u64 *node;
48842b30 1942
84cd17c6 1943 __lookup_session_by_app(usess, app, &iter);
d9bf3ca4 1944 node = lttng_ht_iter_get_node_u64(&iter);
48842b30
DG
1945 if (node == NULL) {
1946 goto error;
1947 }
1948
1949 return caa_container_of(node, struct ust_app_session, node);
1950
1951error:
1952 return NULL;
1953}
1954
7972aab2
DG
1955/*
1956 * Setup buffer registry per PID for the given session and application. If none
1957 * is found, a new one is created, added to the global registry and
1958 * initialized. If regp is valid, it's set with the newly created object.
1959 *
1960 * Return 0 on success or else a negative value.
1961 */
1962static int setup_buffer_reg_pid(struct ust_app_session *ua_sess,
1963 struct ust_app *app, struct buffer_reg_pid **regp)
1964{
1965 int ret = 0;
1966 struct buffer_reg_pid *reg_pid;
1967
1968 assert(ua_sess);
1969 assert(app);
1970
1971 rcu_read_lock();
1972
1973 reg_pid = buffer_reg_pid_find(ua_sess->id);
1974 if (!reg_pid) {
1975 /*
1976 * This is the create channel path meaning that if there is NO
1977 * registry available, we have to create one for this session.
1978 */
d7ba1388 1979 ret = buffer_reg_pid_create(ua_sess->id, &reg_pid,
3d071855 1980 ua_sess->root_shm_path, ua_sess->shm_path);
7972aab2
DG
1981 if (ret < 0) {
1982 goto error;
1983 }
7972aab2
DG
1984 } else {
1985 goto end;
1986 }
1987
1988 /* Initialize registry. */
1989 ret = ust_registry_session_init(&reg_pid->registry->reg.ust, app,
1990 app->bits_per_long, app->uint8_t_alignment,
1991 app->uint16_t_alignment, app->uint32_t_alignment,
af6142cf 1992 app->uint64_t_alignment, app->long_alignment,
470cc211
JG
1993 app->byte_order, app->version.major, app->version.minor,
1994 reg_pid->root_shm_path, reg_pid->shm_path,
1995 ua_sess->effective_credentials.uid,
8de88061
JR
1996 ua_sess->effective_credentials.gid, ua_sess->tracing_id,
1997 app->uid);
7972aab2 1998 if (ret < 0) {
286c991a
MD
1999 /*
2000 * reg_pid->registry->reg.ust is NULL upon error, so we need to
2001 * destroy the buffer registry, because it is always expected
2002 * that if the buffer registry can be found, its ust registry is
2003 * non-NULL.
2004 */
2005 buffer_reg_pid_destroy(reg_pid);
7972aab2
DG
2006 goto error;
2007 }
2008
286c991a
MD
2009 buffer_reg_pid_add(reg_pid);
2010
7972aab2
DG
2011 DBG3("UST app buffer registry per PID created successfully");
2012
2013end:
2014 if (regp) {
2015 *regp = reg_pid;
2016 }
2017error:
2018 rcu_read_unlock();
2019 return ret;
2020}
2021
2022/*
2023 * Setup buffer registry per UID for the given session and application. If none
2024 * is found, a new one is created, added to the global registry and
2025 * initialized. If regp is valid, it's set with the newly created object.
2026 *
2027 * Return 0 on success or else a negative value.
2028 */
2029static int setup_buffer_reg_uid(struct ltt_ust_session *usess,
d7ba1388 2030 struct ust_app_session *ua_sess,
7972aab2
DG
2031 struct ust_app *app, struct buffer_reg_uid **regp)
2032{
2033 int ret = 0;
2034 struct buffer_reg_uid *reg_uid;
2035
2036 assert(usess);
2037 assert(app);
2038
2039 rcu_read_lock();
2040
2041 reg_uid = buffer_reg_uid_find(usess->id, app->bits_per_long, app->uid);
2042 if (!reg_uid) {
2043 /*
2044 * This is the create channel path meaning that if there is NO
2045 * registry available, we have to create one for this session.
2046 */
2047 ret = buffer_reg_uid_create(usess->id, app->bits_per_long, app->uid,
3d071855
MD
2048 LTTNG_DOMAIN_UST, &reg_uid,
2049 ua_sess->root_shm_path, ua_sess->shm_path);
7972aab2
DG
2050 if (ret < 0) {
2051 goto error;
2052 }
7972aab2
DG
2053 } else {
2054 goto end;
2055 }
2056
2057 /* Initialize registry. */
af6142cf 2058 ret = ust_registry_session_init(&reg_uid->registry->reg.ust, NULL,
7972aab2
DG
2059 app->bits_per_long, app->uint8_t_alignment,
2060 app->uint16_t_alignment, app->uint32_t_alignment,
af6142cf
MD
2061 app->uint64_t_alignment, app->long_alignment,
2062 app->byte_order, app->version.major,
3d071855 2063 app->version.minor, reg_uid->root_shm_path,
8de88061
JR
2064 reg_uid->shm_path, usess->uid, usess->gid,
2065 ua_sess->tracing_id, app->uid);
7972aab2 2066 if (ret < 0) {
286c991a
MD
2067 /*
2068 * reg_uid->registry->reg.ust is NULL upon error, so we need to
2069 * destroy the buffer registry, because it is always expected
2070 * that if the buffer registry can be found, its ust registry is
2071 * non-NULL.
2072 */
2073 buffer_reg_uid_destroy(reg_uid, NULL);
7972aab2
DG
2074 goto error;
2075 }
2076 /* Add node to teardown list of the session. */
2077 cds_list_add(&reg_uid->lnode, &usess->buffer_reg_uid_list);
2078
286c991a 2079 buffer_reg_uid_add(reg_uid);
7972aab2 2080
286c991a 2081 DBG3("UST app buffer registry per UID created successfully");
7972aab2
DG
2082end:
2083 if (regp) {
2084 *regp = reg_uid;
2085 }
2086error:
2087 rcu_read_unlock();
2088 return ret;
2089}
2090
421cb601 2091/*
3d8ca23b 2092 * Create a session on the tracer side for the given app.
421cb601 2093 *
3d8ca23b
DG
2094 * On success, ua_sess_ptr is populated with the session pointer or else left
2095 * untouched. If the session was created, is_created is set to 1. On error,
2096 * it's left untouched. Note that ua_sess_ptr is mandatory but is_created can
2097 * be NULL.
2098 *
2099 * Returns 0 on success or else a negative code which is either -ENOMEM or
2100 * -ENOTCONN which is the default code if the ustctl_create_session fails.
421cb601 2101 */
03f91eaa 2102static int find_or_create_ust_app_session(struct ltt_ust_session *usess,
3d8ca23b
DG
2103 struct ust_app *app, struct ust_app_session **ua_sess_ptr,
2104 int *is_created)
421cb601 2105{
3d8ca23b 2106 int ret, created = 0;
421cb601
DG
2107 struct ust_app_session *ua_sess;
2108
3d8ca23b
DG
2109 assert(usess);
2110 assert(app);
2111 assert(ua_sess_ptr);
2112
840cb59c 2113 health_code_update();
86acf0da 2114
421cb601
DG
2115 ua_sess = lookup_session_by_app(usess, app);
2116 if (ua_sess == NULL) {
d9bf3ca4 2117 DBG2("UST app pid: %d session id %" PRIu64 " not found, creating it",
852d0037 2118 app->pid, usess->id);
40bbd087 2119 ua_sess = alloc_ust_app_session();
421cb601
DG
2120 if (ua_sess == NULL) {
2121 /* Only malloc can failed so something is really wrong */
3d8ca23b
DG
2122 ret = -ENOMEM;
2123 goto error;
421cb601 2124 }
477d7741 2125 shadow_copy_session(ua_sess, usess, app);
3d8ca23b 2126 created = 1;
421cb601
DG
2127 }
2128
7972aab2
DG
2129 switch (usess->buffer_type) {
2130 case LTTNG_BUFFER_PER_PID:
2131 /* Init local registry. */
2132 ret = setup_buffer_reg_pid(ua_sess, app, NULL);
421cb601 2133 if (ret < 0) {
e64207cf 2134 delete_ust_app_session(-1, ua_sess, app);
7972aab2
DG
2135 goto error;
2136 }
2137 break;
2138 case LTTNG_BUFFER_PER_UID:
2139 /* Look for a global registry. If none exists, create one. */
d7ba1388 2140 ret = setup_buffer_reg_uid(usess, ua_sess, app, NULL);
7972aab2 2141 if (ret < 0) {
e64207cf 2142 delete_ust_app_session(-1, ua_sess, app);
7972aab2
DG
2143 goto error;
2144 }
2145 break;
2146 default:
2147 assert(0);
2148 ret = -EINVAL;
2149 goto error;
2150 }
2151
2152 health_code_update();
2153
2154 if (ua_sess->handle == -1) {
fb45065e 2155 pthread_mutex_lock(&app->sock_lock);
7972aab2 2156 ret = ustctl_create_session(app->sock);
fb45065e 2157 pthread_mutex_unlock(&app->sock_lock);
7972aab2
DG
2158 if (ret < 0) {
2159 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
2160 ERR("Creating session for app pid %d with ret %d",
ffe60014
DG
2161 app->pid, ret);
2162 } else {
2163 DBG("UST app creating session failed. Application is dead");
3757b385
DG
2164 /*
2165 * This is normal behavior, an application can die during the
2166 * creation process. Don't report an error so the execution can
2167 * continue normally. This will get flagged ENOTCONN and the
2168 * caller will handle it.
2169 */
2170 ret = 0;
ffe60014 2171 }
d0b96690 2172 delete_ust_app_session(-1, ua_sess, app);
3d8ca23b
DG
2173 if (ret != -ENOMEM) {
2174 /*
2175 * Tracer is probably gone or got an internal error so let's
2176 * behave like it will soon unregister or not usable.
2177 */
2178 ret = -ENOTCONN;
2179 }
2180 goto error;
421cb601
DG
2181 }
2182
7972aab2
DG
2183 ua_sess->handle = ret;
2184
2185 /* Add ust app session to app's HT */
d9bf3ca4
MD
2186 lttng_ht_node_init_u64(&ua_sess->node,
2187 ua_sess->tracing_id);
2188 lttng_ht_add_unique_u64(app->sessions, &ua_sess->node);
10b56aef
MD
2189 lttng_ht_node_init_ulong(&ua_sess->ust_objd_node, ua_sess->handle);
2190 lttng_ht_add_unique_ulong(app->ust_sessions_objd,
2191 &ua_sess->ust_objd_node);
7972aab2
DG
2192
2193 DBG2("UST app session created successfully with handle %d", ret);
2194 }
2195
2196 *ua_sess_ptr = ua_sess;
2197 if (is_created) {
2198 *is_created = created;
2199 }
2200
2201 /* Everything went well. */
2202 ret = 0;
2203
2204error:
2205 health_code_update();
2206 return ret;
2207}
2208
6a6b2068
JG
2209/*
2210 * Match function for a hash table lookup of ust_app_ctx.
2211 *
2212 * It matches an ust app context based on the context type and, in the case
2213 * of perf counters, their name.
2214 */
2215static int ht_match_ust_app_ctx(struct cds_lfht_node *node, const void *_key)
2216{
2217 struct ust_app_ctx *ctx;
bdf64013 2218 const struct lttng_ust_context_attr *key;
6a6b2068
JG
2219
2220 assert(node);
2221 assert(_key);
2222
2223 ctx = caa_container_of(node, struct ust_app_ctx, node.node);
2224 key = _key;
2225
2226 /* Context type */
2227 if (ctx->ctx.ctx != key->ctx) {
2228 goto no_match;
2229 }
2230
bdf64013
JG
2231 switch(key->ctx) {
2232 case LTTNG_UST_CONTEXT_PERF_THREAD_COUNTER:
6a6b2068 2233 if (strncmp(key->u.perf_counter.name,
bdf64013
JG
2234 ctx->ctx.u.perf_counter.name,
2235 sizeof(key->u.perf_counter.name))) {
2236 goto no_match;
2237 }
2238 break;
2239 case LTTNG_UST_CONTEXT_APP_CONTEXT:
2240 if (strcmp(key->u.app_ctx.provider_name,
2241 ctx->ctx.u.app_ctx.provider_name) ||
2242 strcmp(key->u.app_ctx.ctx_name,
2243 ctx->ctx.u.app_ctx.ctx_name)) {
6a6b2068
JG
2244 goto no_match;
2245 }
bdf64013
JG
2246 break;
2247 default:
2248 break;
6a6b2068
JG
2249 }
2250
2251 /* Match. */
2252 return 1;
2253
2254no_match:
2255 return 0;
2256}
2257
2258/*
2259 * Lookup for an ust app context from an lttng_ust_context.
2260 *
be184a0f 2261 * Must be called while holding RCU read side lock.
6a6b2068
JG
2262 * Return an ust_app_ctx object or NULL on error.
2263 */
2264static
2265struct ust_app_ctx *find_ust_app_context(struct lttng_ht *ht,
bdf64013 2266 struct lttng_ust_context_attr *uctx)
6a6b2068
JG
2267{
2268 struct lttng_ht_iter iter;
2269 struct lttng_ht_node_ulong *node;
2270 struct ust_app_ctx *app_ctx = NULL;
2271
2272 assert(uctx);
2273 assert(ht);
2274
2275 /* Lookup using the lttng_ust_context_type and a custom match fct. */
2276 cds_lfht_lookup(ht->ht, ht->hash_fct((void *) uctx->ctx, lttng_ht_seed),
2277 ht_match_ust_app_ctx, uctx, &iter.iter);
2278 node = lttng_ht_iter_get_node_ulong(&iter);
2279 if (!node) {
2280 goto end;
2281 }
2282
2283 app_ctx = caa_container_of(node, struct ust_app_ctx, node);
2284
2285end:
2286 return app_ctx;
2287}
2288
7972aab2
DG
2289/*
2290 * Create a context for the channel on the tracer.
2291 *
2292 * Called with UST app session lock held and a RCU read side lock.
2293 */
2294static
c9edf082 2295int create_ust_app_channel_context(struct ust_app_channel *ua_chan,
bdf64013 2296 struct lttng_ust_context_attr *uctx,
7972aab2
DG
2297 struct ust_app *app)
2298{
2299 int ret = 0;
7972aab2
DG
2300 struct ust_app_ctx *ua_ctx;
2301
2302 DBG2("UST app adding context to channel %s", ua_chan->name);
2303
6a6b2068
JG
2304 ua_ctx = find_ust_app_context(ua_chan->ctx, uctx);
2305 if (ua_ctx) {
7972aab2
DG
2306 ret = -EEXIST;
2307 goto error;
2308 }
2309
2310 ua_ctx = alloc_ust_app_ctx(uctx);
2311 if (ua_ctx == NULL) {
2312 /* malloc failed */
7682f304 2313 ret = -ENOMEM;
7972aab2
DG
2314 goto error;
2315 }
2316
2317 lttng_ht_node_init_ulong(&ua_ctx->node, (unsigned long) ua_ctx->ctx.ctx);
aa3514e9 2318 lttng_ht_add_ulong(ua_chan->ctx, &ua_ctx->node);
31746f93 2319 cds_list_add_tail(&ua_ctx->list, &ua_chan->ctx_list);
7972aab2
DG
2320
2321 ret = create_ust_channel_context(ua_chan, ua_ctx, app);
2322 if (ret < 0) {
2323 goto error;
2324 }
2325
2326error:
2327 return ret;
2328}
2329
2330/*
2331 * Enable on the tracer side a ust app event for the session and channel.
2332 *
2333 * Called with UST app session lock held.
2334 */
2335static
2336int enable_ust_app_event(struct ust_app_session *ua_sess,
2337 struct ust_app_event *ua_event, struct ust_app *app)
2338{
2339 int ret;
2340
2341 ret = enable_ust_event(app, ua_sess, ua_event);
2342 if (ret < 0) {
2343 goto error;
2344 }
2345
2346 ua_event->enabled = 1;
2347
2348error:
2349 return ret;
2350}
2351
2352/*
2353 * Disable on the tracer side a ust app event for the session and channel.
2354 */
2355static int disable_ust_app_event(struct ust_app_session *ua_sess,
2356 struct ust_app_event *ua_event, struct ust_app *app)
2357{
2358 int ret;
2359
2360 ret = disable_ust_event(app, ua_sess, ua_event);
2361 if (ret < 0) {
2362 goto error;
2363 }
2364
2365 ua_event->enabled = 0;
2366
2367error:
2368 return ret;
2369}
2370
2371/*
2372 * Lookup ust app channel for session and disable it on the tracer side.
2373 */
2374static
2375int disable_ust_app_channel(struct ust_app_session *ua_sess,
2376 struct ust_app_channel *ua_chan, struct ust_app *app)
2377{
2378 int ret;
2379
2380 ret = disable_ust_channel(app, ua_sess, ua_chan);
2381 if (ret < 0) {
2382 goto error;
2383 }
2384
2385 ua_chan->enabled = 0;
2386
2387error:
2388 return ret;
2389}
2390
2391/*
2392 * Lookup ust app channel for session and enable it on the tracer side. This
2393 * MUST be called with a RCU read side lock acquired.
2394 */
2395static int enable_ust_app_channel(struct ust_app_session *ua_sess,
2396 struct ltt_ust_channel *uchan, struct ust_app *app)
2397{
2398 int ret = 0;
2399 struct lttng_ht_iter iter;
2400 struct lttng_ht_node_str *ua_chan_node;
2401 struct ust_app_channel *ua_chan;
2402
2403 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
2404 ua_chan_node = lttng_ht_iter_get_node_str(&iter);
2405 if (ua_chan_node == NULL) {
d9bf3ca4 2406 DBG2("Unable to find channel %s in ust session id %" PRIu64,
7972aab2
DG
2407 uchan->name, ua_sess->tracing_id);
2408 goto error;
2409 }
2410
2411 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
2412
2413 ret = enable_ust_channel(app, ua_sess, ua_chan);
2414 if (ret < 0) {
2415 goto error;
2416 }
2417
2418error:
2419 return ret;
2420}
2421
2422/*
2423 * Ask the consumer to create a channel and get it if successful.
2424 *
fad1ed2f
JR
2425 * Called with UST app session lock held.
2426 *
7972aab2
DG
2427 * Return 0 on success or else a negative value.
2428 */
2429static int do_consumer_create_channel(struct ltt_ust_session *usess,
2430 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan,
e098433c
JG
2431 int bitness, struct ust_registry_session *registry,
2432 uint64_t trace_archive_id)
7972aab2
DG
2433{
2434 int ret;
2435 unsigned int nb_fd = 0;
2436 struct consumer_socket *socket;
2437
2438 assert(usess);
2439 assert(ua_sess);
2440 assert(ua_chan);
2441 assert(registry);
2442
2443 rcu_read_lock();
2444 health_code_update();
2445
2446 /* Get the right consumer socket for the application. */
2447 socket = consumer_find_socket_by_bitness(bitness, usess->consumer);
2448 if (!socket) {
2449 ret = -EINVAL;
2450 goto error;
2451 }
2452
2453 health_code_update();
2454
2455 /* Need one fd for the channel. */
2456 ret = lttng_fd_get(LTTNG_FD_APPS, 1);
2457 if (ret < 0) {
2458 ERR("Exhausted number of available FD upon create channel");
2459 goto error;
2460 }
2461
2462 /*
2463 * Ask consumer to create channel. The consumer will return the number of
2464 * stream we have to expect.
2465 */
2466 ret = ust_consumer_ask_channel(ua_sess, ua_chan, usess->consumer, socket,
d2956687 2467 registry, usess->current_trace_chunk);
7972aab2
DG
2468 if (ret < 0) {
2469 goto error_ask;
2470 }
2471
2472 /*
2473 * Compute the number of fd needed before receiving them. It must be 2 per
2474 * stream (2 being the default value here).
2475 */
2476 nb_fd = DEFAULT_UST_STREAM_FD_NUM * ua_chan->expected_stream_count;
2477
2478 /* Reserve the amount of file descriptor we need. */
2479 ret = lttng_fd_get(LTTNG_FD_APPS, nb_fd);
2480 if (ret < 0) {
2481 ERR("Exhausted number of available FD upon create channel");
2482 goto error_fd_get_stream;
2483 }
2484
2485 health_code_update();
2486
2487 /*
2488 * Now get the channel from the consumer. This call wil populate the stream
2489 * list of that channel and set the ust objects.
2490 */
d9078d0c
DG
2491 if (usess->consumer->enabled) {
2492 ret = ust_consumer_get_channel(socket, ua_chan);
2493 if (ret < 0) {
2494 goto error_destroy;
2495 }
7972aab2
DG
2496 }
2497
2498 rcu_read_unlock();
2499 return 0;
2500
2501error_destroy:
2502 lttng_fd_put(LTTNG_FD_APPS, nb_fd);
2503error_fd_get_stream:
2504 /*
2505 * Initiate a destroy channel on the consumer since we had an error
2506 * handling it on our side. The return value is of no importance since we
2507 * already have a ret value set by the previous error that we need to
2508 * return.
2509 */
2510 (void) ust_consumer_destroy_channel(socket, ua_chan);
2511error_ask:
2512 lttng_fd_put(LTTNG_FD_APPS, 1);
2513error:
2514 health_code_update();
2515 rcu_read_unlock();
2516 return ret;
2517}
2518
2519/*
2520 * Duplicate the ust data object of the ust app stream and save it in the
2521 * buffer registry stream.
2522 *
2523 * Return 0 on success or else a negative value.
2524 */
2525static int duplicate_stream_object(struct buffer_reg_stream *reg_stream,
2526 struct ust_app_stream *stream)
2527{
2528 int ret;
2529
2530 assert(reg_stream);
2531 assert(stream);
2532
2533 /* Reserve the amount of file descriptor we need. */
2534 ret = lttng_fd_get(LTTNG_FD_APPS, 2);
2535 if (ret < 0) {
2536 ERR("Exhausted number of available FD upon duplicate stream");
2537 goto error;
2538 }
2539
2540 /* Duplicate object for stream once the original is in the registry. */
2541 ret = ustctl_duplicate_ust_object_data(&stream->obj,
2542 reg_stream->obj.ust);
2543 if (ret < 0) {
2544 ERR("Duplicate stream obj from %p to %p failed with ret %d",
2545 reg_stream->obj.ust, stream->obj, ret);
2546 lttng_fd_put(LTTNG_FD_APPS, 2);
2547 goto error;
2548 }
2549 stream->handle = stream->obj->handle;
2550
2551error:
2552 return ret;
2553}
2554
2555/*
2556 * Duplicate the ust data object of the ust app. channel and save it in the
2557 * buffer registry channel.
2558 *
2559 * Return 0 on success or else a negative value.
2560 */
2561static int duplicate_channel_object(struct buffer_reg_channel *reg_chan,
2562 struct ust_app_channel *ua_chan)
2563{
2564 int ret;
2565
2566 assert(reg_chan);
2567 assert(ua_chan);
2568
2569 /* Need two fds for the channel. */
2570 ret = lttng_fd_get(LTTNG_FD_APPS, 1);
2571 if (ret < 0) {
2572 ERR("Exhausted number of available FD upon duplicate channel");
2573 goto error_fd_get;
2574 }
2575
2576 /* Duplicate object for stream once the original is in the registry. */
2577 ret = ustctl_duplicate_ust_object_data(&ua_chan->obj, reg_chan->obj.ust);
2578 if (ret < 0) {
2579 ERR("Duplicate channel obj from %p to %p failed with ret: %d",
2580 reg_chan->obj.ust, ua_chan->obj, ret);
2581 goto error;
2582 }
2583 ua_chan->handle = ua_chan->obj->handle;
2584
2585 return 0;
2586
2587error:
2588 lttng_fd_put(LTTNG_FD_APPS, 1);
2589error_fd_get:
2590 return ret;
2591}
2592
2593/*
2594 * For a given channel buffer registry, setup all streams of the given ust
2595 * application channel.
2596 *
2597 * Return 0 on success or else a negative value.
2598 */
2599static int setup_buffer_reg_streams(struct buffer_reg_channel *reg_chan,
fb45065e
MD
2600 struct ust_app_channel *ua_chan,
2601 struct ust_app *app)
7972aab2
DG
2602{
2603 int ret = 0;
2604 struct ust_app_stream *stream, *stmp;
2605
2606 assert(reg_chan);
2607 assert(ua_chan);
2608
2609 DBG2("UST app setup buffer registry stream");
2610
2611 /* Send all streams to application. */
2612 cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
2613 struct buffer_reg_stream *reg_stream;
2614
2615 ret = buffer_reg_stream_create(&reg_stream);
2616 if (ret < 0) {
2617 goto error;
2618 }
2619
2620 /*
2621 * Keep original pointer and nullify it in the stream so the delete
2622 * stream call does not release the object.
2623 */
2624 reg_stream->obj.ust = stream->obj;
2625 stream->obj = NULL;
2626 buffer_reg_stream_add(reg_stream, reg_chan);
421cb601 2627
7972aab2
DG
2628 /* We don't need the streams anymore. */
2629 cds_list_del(&stream->list);
fb45065e 2630 delete_ust_app_stream(-1, stream, app);
7972aab2 2631 }
421cb601 2632
7972aab2
DG
2633error:
2634 return ret;
2635}
2636
2637/*
2638 * Create a buffer registry channel for the given session registry and
2639 * application channel object. If regp pointer is valid, it's set with the
2640 * created object. Important, the created object is NOT added to the session
2641 * registry hash table.
2642 *
2643 * Return 0 on success else a negative value.
2644 */
2645static int create_buffer_reg_channel(struct buffer_reg_session *reg_sess,
2646 struct ust_app_channel *ua_chan, struct buffer_reg_channel **regp)
2647{
2648 int ret;
2649 struct buffer_reg_channel *reg_chan = NULL;
2650
2651 assert(reg_sess);
2652 assert(ua_chan);
2653
2654 DBG2("UST app creating buffer registry channel for %s", ua_chan->name);
2655
2656 /* Create buffer registry channel. */
2657 ret = buffer_reg_channel_create(ua_chan->tracing_channel_id, &reg_chan);
2658 if (ret < 0) {
2659 goto error_create;
421cb601 2660 }
7972aab2
DG
2661 assert(reg_chan);
2662 reg_chan->consumer_key = ua_chan->key;
8c924c7b 2663 reg_chan->subbuf_size = ua_chan->attr.subbuf_size;
d07ceecd 2664 reg_chan->num_subbuf = ua_chan->attr.num_subbuf;
421cb601 2665
7972aab2
DG
2666 /* Create and add a channel registry to session. */
2667 ret = ust_registry_channel_add(reg_sess->reg.ust,
2668 ua_chan->tracing_channel_id);
2669 if (ret < 0) {
2670 goto error;
d88aee68 2671 }
7972aab2 2672 buffer_reg_channel_add(reg_sess, reg_chan);
d88aee68 2673
7972aab2
DG
2674 if (regp) {
2675 *regp = reg_chan;
3d8ca23b 2676 }
d88aee68 2677
7972aab2 2678 return 0;
3d8ca23b
DG
2679
2680error:
7972aab2
DG
2681 /* Safe because the registry channel object was not added to any HT. */
2682 buffer_reg_channel_destroy(reg_chan, LTTNG_DOMAIN_UST);
2683error_create:
3d8ca23b 2684 return ret;
421cb601
DG
2685}
2686
55cc08a6 2687/*
7972aab2
DG
2688 * Setup buffer registry channel for the given session registry and application
2689 * channel object. If regp pointer is valid, it's set with the created object.
d0b96690 2690 *
7972aab2 2691 * Return 0 on success else a negative value.
55cc08a6 2692 */
7972aab2 2693static int setup_buffer_reg_channel(struct buffer_reg_session *reg_sess,
fb45065e
MD
2694 struct ust_app_channel *ua_chan, struct buffer_reg_channel *reg_chan,
2695 struct ust_app *app)
55cc08a6 2696{
7972aab2 2697 int ret;
55cc08a6 2698
7972aab2
DG
2699 assert(reg_sess);
2700 assert(reg_chan);
2701 assert(ua_chan);
2702 assert(ua_chan->obj);
55cc08a6 2703
7972aab2 2704 DBG2("UST app setup buffer registry channel for %s", ua_chan->name);
55cc08a6 2705
7972aab2 2706 /* Setup all streams for the registry. */
fb45065e 2707 ret = setup_buffer_reg_streams(reg_chan, ua_chan, app);
7972aab2 2708 if (ret < 0) {
55cc08a6
DG
2709 goto error;
2710 }
2711
7972aab2
DG
2712 reg_chan->obj.ust = ua_chan->obj;
2713 ua_chan->obj = NULL;
55cc08a6 2714
7972aab2 2715 return 0;
55cc08a6
DG
2716
2717error:
7972aab2
DG
2718 buffer_reg_channel_remove(reg_sess, reg_chan);
2719 buffer_reg_channel_destroy(reg_chan, LTTNG_DOMAIN_UST);
55cc08a6
DG
2720 return ret;
2721}
2722
edb67388 2723/*
7972aab2 2724 * Send buffer registry channel to the application.
d0b96690 2725 *
7972aab2 2726 * Return 0 on success else a negative value.
edb67388 2727 */
7972aab2
DG
2728static int send_channel_uid_to_ust(struct buffer_reg_channel *reg_chan,
2729 struct ust_app *app, struct ust_app_session *ua_sess,
2730 struct ust_app_channel *ua_chan)
edb67388
DG
2731{
2732 int ret;
7972aab2 2733 struct buffer_reg_stream *reg_stream;
edb67388 2734
7972aab2
DG
2735 assert(reg_chan);
2736 assert(app);
2737 assert(ua_sess);
2738 assert(ua_chan);
2739
2740 DBG("UST app sending buffer registry channel to ust sock %d", app->sock);
2741
2742 ret = duplicate_channel_object(reg_chan, ua_chan);
edb67388
DG
2743 if (ret < 0) {
2744 goto error;
2745 }
2746
7972aab2
DG
2747 /* Send channel to the application. */
2748 ret = ust_consumer_send_channel_to_ust(app, ua_sess, ua_chan);
a7169585
MD
2749 if (ret == -EPIPE || ret == -LTTNG_UST_ERR_EXITING) {
2750 ret = -ENOTCONN; /* Caused by app exiting. */
2751 goto error;
2752 } else if (ret < 0) {
7972aab2
DG
2753 goto error;
2754 }
2755
2756 health_code_update();
2757
2758 /* Send all streams to application. */
2759 pthread_mutex_lock(&reg_chan->stream_list_lock);
2760 cds_list_for_each_entry(reg_stream, &reg_chan->streams, lnode) {
2761 struct ust_app_stream stream;
2762
2763 ret = duplicate_stream_object(reg_stream, &stream);
2764 if (ret < 0) {
2765 goto error_stream_unlock;
2766 }
2767
2768 ret = ust_consumer_send_stream_to_ust(app, ua_chan, &stream);
2769 if (ret < 0) {
fb45065e 2770 (void) release_ust_app_stream(-1, &stream, app);
a7169585
MD
2771 if (ret == -EPIPE || ret == -LTTNG_UST_ERR_EXITING) {
2772 ret = -ENOTCONN; /* Caused by app exiting. */
a7169585 2773 }
7972aab2
DG
2774 goto error_stream_unlock;
2775 }
edb67388 2776
7972aab2
DG
2777 /*
2778 * The return value is not important here. This function will output an
2779 * error if needed.
2780 */
fb45065e 2781 (void) release_ust_app_stream(-1, &stream, app);
7972aab2
DG
2782 }
2783 ua_chan->is_sent = 1;
2784
2785error_stream_unlock:
2786 pthread_mutex_unlock(&reg_chan->stream_list_lock);
edb67388
DG
2787error:
2788 return ret;
2789}
2790
9730260e 2791/*
7972aab2
DG
2792 * Create and send to the application the created buffers with per UID buffers.
2793 *
9acdc1d6 2794 * This MUST be called with a RCU read side lock acquired.
71e0a100 2795 * The session list lock and the session's lock must be acquired.
9acdc1d6 2796 *
7972aab2 2797 * Return 0 on success else a negative value.
9730260e 2798 */
7972aab2
DG
2799static int create_channel_per_uid(struct ust_app *app,
2800 struct ltt_ust_session *usess, struct ust_app_session *ua_sess,
2801 struct ust_app_channel *ua_chan)
9730260e
DG
2802{
2803 int ret;
7972aab2
DG
2804 struct buffer_reg_uid *reg_uid;
2805 struct buffer_reg_channel *reg_chan;
e32d7f27 2806 struct ltt_session *session = NULL;
e098433c
JG
2807 enum lttng_error_code notification_ret;
2808 struct ust_registry_channel *chan_reg;
9730260e 2809
7972aab2
DG
2810 assert(app);
2811 assert(usess);
2812 assert(ua_sess);
2813 assert(ua_chan);
2814
2815 DBG("UST app creating channel %s with per UID buffers", ua_chan->name);
2816
2817 reg_uid = buffer_reg_uid_find(usess->id, app->bits_per_long, app->uid);
2818 /*
2819 * The session creation handles the creation of this global registry
2820 * object. If none can be find, there is a code flow problem or a
2821 * teardown race.
2822 */
2823 assert(reg_uid);
2824
2825 reg_chan = buffer_reg_channel_find(ua_chan->tracing_channel_id,
2826 reg_uid);
2721f7ea
JG
2827 if (reg_chan) {
2828 goto send_channel;
2829 }
7972aab2 2830
2721f7ea
JG
2831 /* Create the buffer registry channel object. */
2832 ret = create_buffer_reg_channel(reg_uid->registry, ua_chan, &reg_chan);
2833 if (ret < 0) {
2834 ERR("Error creating the UST channel \"%s\" registry instance",
f14256d6 2835 ua_chan->name);
2721f7ea
JG
2836 goto error;
2837 }
f14256d6 2838
e098433c
JG
2839 session = session_find_by_id(ua_sess->tracing_id);
2840 assert(session);
2841 assert(pthread_mutex_trylock(&session->lock));
2842 assert(session_trylock_list());
2843
2721f7ea
JG
2844 /*
2845 * Create the buffers on the consumer side. This call populates the
2846 * ust app channel object with all streams and data object.
2847 */
2848 ret = do_consumer_create_channel(usess, ua_sess, ua_chan,
e098433c 2849 app->bits_per_long, reg_uid->registry->reg.ust,
d2956687 2850 session->most_recent_chunk_id.value);
2721f7ea
JG
2851 if (ret < 0) {
2852 ERR("Error creating UST channel \"%s\" on the consumer daemon",
2853 ua_chan->name);
7972aab2
DG
2854
2855 /*
2721f7ea
JG
2856 * Let's remove the previously created buffer registry channel so
2857 * it's not visible anymore in the session registry.
7972aab2 2858 */
2721f7ea
JG
2859 ust_registry_channel_del_free(reg_uid->registry->reg.ust,
2860 ua_chan->tracing_channel_id, false);
2861 buffer_reg_channel_remove(reg_uid->registry, reg_chan);
2862 buffer_reg_channel_destroy(reg_chan, LTTNG_DOMAIN_UST);
2863 goto error;
7972aab2
DG
2864 }
2865
2721f7ea
JG
2866 /*
2867 * Setup the streams and add it to the session registry.
2868 */
2869 ret = setup_buffer_reg_channel(reg_uid->registry,
2870 ua_chan, reg_chan, app);
2871 if (ret < 0) {
2872 ERR("Error setting up UST channel \"%s\"", ua_chan->name);
2873 goto error;
2874 }
2875
e098433c
JG
2876 /* Notify the notification subsystem of the channel's creation. */
2877 pthread_mutex_lock(&reg_uid->registry->reg.ust->lock);
2878 chan_reg = ust_registry_channel_find(reg_uid->registry->reg.ust,
2879 ua_chan->tracing_channel_id);
2880 assert(chan_reg);
2881 chan_reg->consumer_key = ua_chan->key;
2882 chan_reg = NULL;
2883 pthread_mutex_unlock(&reg_uid->registry->reg.ust->lock);
e9404c27 2884
e098433c
JG
2885 notification_ret = notification_thread_command_add_channel(
2886 notification_thread_handle, session->name,
470cc211
JG
2887 ua_sess->effective_credentials.uid,
2888 ua_sess->effective_credentials.gid, ua_chan->name,
2889 ua_chan->key, LTTNG_DOMAIN_UST,
e098433c
JG
2890 ua_chan->attr.subbuf_size * ua_chan->attr.num_subbuf);
2891 if (notification_ret != LTTNG_OK) {
2892 ret = - (int) notification_ret;
2893 ERR("Failed to add channel to notification thread");
2894 goto error;
e9404c27
JG
2895 }
2896
2721f7ea 2897send_channel:
66ff8e3f
JG
2898 /* Send buffers to the application. */
2899 ret = send_channel_uid_to_ust(reg_chan, app, ua_sess, ua_chan);
2900 if (ret < 0) {
2901 if (ret != -ENOTCONN) {
2902 ERR("Error sending channel to application");
2903 }
2904 goto error;
2905 }
2906
9730260e 2907error:
e32d7f27
JG
2908 if (session) {
2909 session_put(session);
2910 }
9730260e
DG
2911 return ret;
2912}
2913
78f0bacd 2914/*
7972aab2
DG
2915 * Create and send to the application the created buffers with per PID buffers.
2916 *
fad1ed2f 2917 * Called with UST app session lock held.
71e0a100 2918 * The session list lock and the session's lock must be acquired.
fad1ed2f 2919 *
7972aab2 2920 * Return 0 on success else a negative value.
78f0bacd 2921 */
7972aab2
DG
2922static int create_channel_per_pid(struct ust_app *app,
2923 struct ltt_ust_session *usess, struct ust_app_session *ua_sess,
2924 struct ust_app_channel *ua_chan)
78f0bacd 2925{
8535a6d9 2926 int ret;
7972aab2 2927 struct ust_registry_session *registry;
e9404c27 2928 enum lttng_error_code cmd_ret;
e32d7f27 2929 struct ltt_session *session = NULL;
e9404c27
JG
2930 uint64_t chan_reg_key;
2931 struct ust_registry_channel *chan_reg;
78f0bacd 2932
7972aab2
DG
2933 assert(app);
2934 assert(usess);
2935 assert(ua_sess);
2936 assert(ua_chan);
2937
2938 DBG("UST app creating channel %s with per PID buffers", ua_chan->name);
2939
2940 rcu_read_lock();
2941
2942 registry = get_session_registry(ua_sess);
fad1ed2f 2943 /* The UST app session lock is held, registry shall not be null. */
7972aab2
DG
2944 assert(registry);
2945
2946 /* Create and add a new channel registry to session. */
2947 ret = ust_registry_channel_add(registry, ua_chan->key);
78f0bacd 2948 if (ret < 0) {
f14256d6
MD
2949 ERR("Error creating the UST channel \"%s\" registry instance",
2950 ua_chan->name);
78f0bacd
DG
2951 goto error;
2952 }
2953
e098433c
JG
2954 session = session_find_by_id(ua_sess->tracing_id);
2955 assert(session);
2956
2957 assert(pthread_mutex_trylock(&session->lock));
2958 assert(session_trylock_list());
2959
7972aab2
DG
2960 /* Create and get channel on the consumer side. */
2961 ret = do_consumer_create_channel(usess, ua_sess, ua_chan,
e098433c 2962 app->bits_per_long, registry,
d2956687 2963 session->most_recent_chunk_id.value);
7972aab2 2964 if (ret < 0) {
f14256d6
MD
2965 ERR("Error creating UST channel \"%s\" on the consumer daemon",
2966 ua_chan->name);
5b951542 2967 goto error_remove_from_registry;
7972aab2
DG
2968 }
2969
2970 ret = send_channel_pid_to_ust(app, ua_sess, ua_chan);
2971 if (ret < 0) {
a7169585
MD
2972 if (ret != -ENOTCONN) {
2973 ERR("Error sending channel to application");
2974 }
5b951542 2975 goto error_remove_from_registry;
7972aab2 2976 }
8535a6d9 2977
e9404c27
JG
2978 chan_reg_key = ua_chan->key;
2979 pthread_mutex_lock(&registry->lock);
2980 chan_reg = ust_registry_channel_find(registry, chan_reg_key);
2981 assert(chan_reg);
2982 chan_reg->consumer_key = ua_chan->key;
2983 pthread_mutex_unlock(&registry->lock);
2984
2985 cmd_ret = notification_thread_command_add_channel(
2986 notification_thread_handle, session->name,
470cc211
JG
2987 ua_sess->effective_credentials.uid,
2988 ua_sess->effective_credentials.gid, ua_chan->name,
2989 ua_chan->key, LTTNG_DOMAIN_UST,
e9404c27
JG
2990 ua_chan->attr.subbuf_size * ua_chan->attr.num_subbuf);
2991 if (cmd_ret != LTTNG_OK) {
2992 ret = - (int) cmd_ret;
2993 ERR("Failed to add channel to notification thread");
5b951542 2994 goto error_remove_from_registry;
e9404c27
JG
2995 }
2996
5b951542
MD
2997error_remove_from_registry:
2998 if (ret) {
2999 ust_registry_channel_del_free(registry, ua_chan->key, false);
3000 }
78f0bacd 3001error:
7972aab2 3002 rcu_read_unlock();
e32d7f27
JG
3003 if (session) {
3004 session_put(session);
3005 }
78f0bacd
DG
3006 return ret;
3007}
3008
3009/*
7972aab2 3010 * From an already allocated ust app channel, create the channel buffers if
88e3c2f5 3011 * needed and send them to the application. This MUST be called with a RCU read
7972aab2
DG
3012 * side lock acquired.
3013 *
fad1ed2f
JR
3014 * Called with UST app session lock held.
3015 *
a7169585
MD
3016 * Return 0 on success or else a negative value. Returns -ENOTCONN if
3017 * the application exited concurrently.
78f0bacd 3018 */
88e3c2f5 3019static int ust_app_channel_send(struct ust_app *app,
7972aab2
DG
3020 struct ltt_ust_session *usess, struct ust_app_session *ua_sess,
3021 struct ust_app_channel *ua_chan)
78f0bacd 3022{
7972aab2 3023 int ret;
78f0bacd 3024
7972aab2
DG
3025 assert(app);
3026 assert(usess);
88e3c2f5 3027 assert(usess->active);
7972aab2
DG
3028 assert(ua_sess);
3029 assert(ua_chan);
3030
3031 /* Handle buffer type before sending the channel to the application. */
3032 switch (usess->buffer_type) {
3033 case LTTNG_BUFFER_PER_UID:
3034 {
3035 ret = create_channel_per_uid(app, usess, ua_sess, ua_chan);
3036 if (ret < 0) {
3037 goto error;
3038 }
3039 break;
3040 }
3041 case LTTNG_BUFFER_PER_PID:
3042 {
3043 ret = create_channel_per_pid(app, usess, ua_sess, ua_chan);
3044 if (ret < 0) {
3045 goto error;
3046 }
3047 break;
3048 }
3049 default:
3050 assert(0);
3051 ret = -EINVAL;
78f0bacd
DG
3052 goto error;
3053 }
3054
7972aab2
DG
3055 /* Initialize ust objd object using the received handle and add it. */
3056 lttng_ht_node_init_ulong(&ua_chan->ust_objd_node, ua_chan->handle);
3057 lttng_ht_add_unique_ulong(app->ust_objd, &ua_chan->ust_objd_node);
78f0bacd 3058
7972aab2
DG
3059 /* If channel is not enabled, disable it on the tracer */
3060 if (!ua_chan->enabled) {
3061 ret = disable_ust_channel(app, ua_sess, ua_chan);
3062 if (ret < 0) {
3063 goto error;
3064 }
78f0bacd
DG
3065 }
3066
3067error:
3068 return ret;
3069}
3070
284d8f55 3071/*
88e3c2f5 3072 * Create UST app channel and return it through ua_chanp if not NULL.
d0b96690 3073 *
36b588ed 3074 * Called with UST app session lock and RCU read-side lock held.
7972aab2 3075 *
88e3c2f5 3076 * Return 0 on success or else a negative value.
284d8f55 3077 */
88e3c2f5
JG
3078static int ust_app_channel_allocate(struct ust_app_session *ua_sess,
3079 struct ltt_ust_channel *uchan,
7972aab2 3080 enum lttng_ust_chan_type type, struct ltt_ust_session *usess,
4d710ac2 3081 struct ust_app_channel **ua_chanp)
5b4a0ec0
DG
3082{
3083 int ret = 0;
bec39940
DG
3084 struct lttng_ht_iter iter;
3085 struct lttng_ht_node_str *ua_chan_node;
5b4a0ec0
DG
3086 struct ust_app_channel *ua_chan;
3087
3088 /* Lookup channel in the ust app session */
bec39940
DG
3089 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
3090 ua_chan_node = lttng_ht_iter_get_node_str(&iter);
fc34caaa 3091 if (ua_chan_node != NULL) {
5b4a0ec0 3092 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
fc34caaa 3093 goto end;
5b4a0ec0
DG
3094 }
3095
d0b96690 3096 ua_chan = alloc_ust_app_channel(uchan->name, ua_sess, &uchan->attr);
fc34caaa
DG
3097 if (ua_chan == NULL) {
3098 /* Only malloc can fail here */
4d710ac2 3099 ret = -ENOMEM;
88e3c2f5 3100 goto error;
fc34caaa
DG
3101 }
3102 shadow_copy_channel(ua_chan, uchan);
3103
ffe60014
DG
3104 /* Set channel type. */
3105 ua_chan->attr.type = type;
3106
d0b96690
DG
3107 /* Only add the channel if successful on the tracer side. */
3108 lttng_ht_add_unique_str(ua_sess->channels, &ua_chan->node);
fc34caaa 3109end:
4d710ac2
DG
3110 if (ua_chanp) {
3111 *ua_chanp = ua_chan;
3112 }
3113
3114 /* Everything went well. */
3115 return 0;
5b4a0ec0
DG
3116
3117error:
4d710ac2 3118 return ret;
5b4a0ec0
DG
3119}
3120
3121/*
3122 * Create UST app event and create it on the tracer side.
d0b96690
DG
3123 *
3124 * Called with ust app session mutex held.
5b4a0ec0 3125 */
edb67388
DG
3126static
3127int create_ust_app_event(struct ust_app_session *ua_sess,
3128 struct ust_app_channel *ua_chan, struct ltt_ust_event *uevent,
3129 struct ust_app *app)
284d8f55 3130{
edb67388 3131 int ret = 0;
5b4a0ec0 3132 struct ust_app_event *ua_event;
284d8f55 3133
edb67388
DG
3134 ua_event = alloc_ust_app_event(uevent->attr.name, &uevent->attr);
3135 if (ua_event == NULL) {
3136 /* Only malloc can failed so something is really wrong */
3137 ret = -ENOMEM;
fc34caaa 3138 goto end;
5b4a0ec0 3139 }
edb67388 3140 shadow_copy_event(ua_event, uevent);
5b4a0ec0 3141
edb67388 3142 /* Create it on the tracer side */
5b4a0ec0 3143 ret = create_ust_event(app, ua_sess, ua_chan, ua_event);
284d8f55 3144 if (ret < 0) {
fc34caaa 3145 /* Not found previously means that it does not exist on the tracer */
76f66f63 3146 assert(ret != -LTTNG_UST_ERR_EXIST);
284d8f55
DG
3147 goto error;
3148 }
3149
d0b96690 3150 add_unique_ust_app_event(ua_chan, ua_event);
284d8f55 3151
fc34caaa 3152 DBG2("UST app create event %s for PID %d completed", ua_event->name,
852d0037 3153 app->pid);
7f79d3a1 3154
edb67388 3155end:
fc34caaa
DG
3156 return ret;
3157
5b4a0ec0 3158error:
fc34caaa 3159 /* Valid. Calling here is already in a read side lock */
fb45065e 3160 delete_ust_app_event(-1, ua_event, app);
edb67388 3161 return ret;
5b4a0ec0
DG
3162}
3163
3164/*
3165 * Create UST metadata and open it on the tracer side.
d0b96690 3166 *
7972aab2 3167 * Called with UST app session lock held and RCU read side lock.
5b4a0ec0
DG
3168 */
3169static int create_ust_app_metadata(struct ust_app_session *ua_sess,
ad7a9107 3170 struct ust_app *app, struct consumer_output *consumer)
5b4a0ec0
DG
3171{
3172 int ret = 0;
ffe60014 3173 struct ust_app_channel *metadata;
d88aee68 3174 struct consumer_socket *socket;
7972aab2 3175 struct ust_registry_session *registry;
e32d7f27 3176 struct ltt_session *session = NULL;
5b4a0ec0 3177
ffe60014
DG
3178 assert(ua_sess);
3179 assert(app);
d88aee68 3180 assert(consumer);
5b4a0ec0 3181
7972aab2 3182 registry = get_session_registry(ua_sess);
fad1ed2f 3183 /* The UST app session is held registry shall not be null. */
7972aab2
DG
3184 assert(registry);
3185
ce34fcd0
MD
3186 pthread_mutex_lock(&registry->lock);
3187
1b532a60
DG
3188 /* Metadata already exists for this registry or it was closed previously */
3189 if (registry->metadata_key || registry->metadata_closed) {
7972aab2
DG
3190 ret = 0;
3191 goto error;
5b4a0ec0
DG
3192 }
3193
ffe60014 3194 /* Allocate UST metadata */
d0b96690 3195 metadata = alloc_ust_app_channel(DEFAULT_METADATA_NAME, ua_sess, NULL);
ffe60014
DG
3196 if (!metadata) {
3197 /* malloc() failed */
3198 ret = -ENOMEM;
3199 goto error;
3200 }
5b4a0ec0 3201
ad7a9107 3202 memcpy(&metadata->attr, &ua_sess->metadata_attr, sizeof(metadata->attr));
5b4a0ec0 3203
7972aab2
DG
3204 /* Need one fd for the channel. */
3205 ret = lttng_fd_get(LTTNG_FD_APPS, 1);
3206 if (ret < 0) {
3207 ERR("Exhausted number of available FD upon create metadata");
3208 goto error;
3209 }
3210
4dc3dfc5
DG
3211 /* Get the right consumer socket for the application. */
3212 socket = consumer_find_socket_by_bitness(app->bits_per_long, consumer);
3213 if (!socket) {
3214 ret = -EINVAL;
3215 goto error_consumer;
3216 }
3217
331744e3
JD
3218 /*
3219 * Keep metadata key so we can identify it on the consumer side. Assign it
3220 * to the registry *before* we ask the consumer so we avoid the race of the
3221 * consumer requesting the metadata and the ask_channel call on our side
3222 * did not returned yet.
3223 */
3224 registry->metadata_key = metadata->key;
3225