Fix: create_channel_per_pid: remove channel on error
[lttng-tools.git] / src / bin / lttng-sessiond / ust-app.c
CommitLineData
91d76f53
DG
1/*
2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
bdf64013 3 * Copyright (C) 2016 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
91d76f53 4 *
d14d33bf
AM
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License, version 2 only,
7 * as published by the Free Software Foundation.
91d76f53
DG
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
d14d33bf
AM
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
91d76f53
DG
17 */
18
6c1c0768 19#define _LGPL_SOURCE
91d76f53 20#include <errno.h>
7972aab2 21#include <inttypes.h>
91d76f53
DG
22#include <pthread.h>
23#include <stdio.h>
24#include <stdlib.h>
099e26bd 25#include <string.h>
aba8e916
DG
26#include <sys/stat.h>
27#include <sys/types.h>
099e26bd 28#include <unistd.h>
0df502fd 29#include <urcu/compiler.h>
fb54cdbf 30#include <lttng/ust-error.h>
331744e3 31#include <signal.h>
bec39940 32
990570ed 33#include <common/common.h>
86acf0da 34#include <common/sessiond-comm/sessiond-comm.h>
1e307fab 35
7972aab2 36#include "buffer-registry.h"
86acf0da 37#include "fd-limit.h"
8782cc74 38#include "health-sessiond.h"
56fff090 39#include "ust-app.h"
48842b30 40#include "ust-consumer.h"
d80a6244 41#include "ust-ctl.h"
0b2dc8df 42#include "utils.h"
fb83fe64 43#include "session.h"
e9404c27
JG
44#include "lttng-sessiond.h"
45#include "notification-thread-commands.h"
5c408ad8 46#include "rotate.h"
d80a6244 47
c4b88406
MD
48static
49int ust_app_flush_app_session(struct ust_app *app, struct ust_app_session *ua_sess);
50
d9bf3ca4
MD
51/* Next available channel key. Access under next_channel_key_lock. */
52static uint64_t _next_channel_key;
53static pthread_mutex_t next_channel_key_lock = PTHREAD_MUTEX_INITIALIZER;
54
55/* Next available session ID. Access under next_session_id_lock. */
56static uint64_t _next_session_id;
57static pthread_mutex_t next_session_id_lock = PTHREAD_MUTEX_INITIALIZER;
ffe60014
DG
58
59/*
d9bf3ca4 60 * Return the incremented value of next_channel_key.
ffe60014 61 */
d9bf3ca4 62static uint64_t get_next_channel_key(void)
ffe60014 63{
d9bf3ca4
MD
64 uint64_t ret;
65
66 pthread_mutex_lock(&next_channel_key_lock);
67 ret = ++_next_channel_key;
68 pthread_mutex_unlock(&next_channel_key_lock);
69 return ret;
ffe60014
DG
70}
71
72/*
7972aab2 73 * Return the atomically incremented value of next_session_id.
ffe60014 74 */
d9bf3ca4 75static uint64_t get_next_session_id(void)
ffe60014 76{
d9bf3ca4
MD
77 uint64_t ret;
78
79 pthread_mutex_lock(&next_session_id_lock);
80 ret = ++_next_session_id;
81 pthread_mutex_unlock(&next_session_id_lock);
82 return ret;
ffe60014
DG
83}
84
d65d2de8
DG
85static void copy_channel_attr_to_ustctl(
86 struct ustctl_consumer_channel_attr *attr,
87 struct lttng_ust_channel_attr *uattr)
88{
89 /* Copy event attributes since the layout is different. */
90 attr->subbuf_size = uattr->subbuf_size;
91 attr->num_subbuf = uattr->num_subbuf;
92 attr->overwrite = uattr->overwrite;
93 attr->switch_timer_interval = uattr->switch_timer_interval;
94 attr->read_timer_interval = uattr->read_timer_interval;
95 attr->output = uattr->output;
491d1539 96 attr->blocking_timeout = uattr->u.s.blocking_timeout;
d65d2de8
DG
97}
98
025faf73
DG
99/*
100 * Match function for the hash table lookup.
101 *
102 * It matches an ust app event based on three attributes which are the event
103 * name, the filter bytecode and the loglevel.
104 */
18eace3b
DG
105static int ht_match_ust_app_event(struct cds_lfht_node *node, const void *_key)
106{
107 struct ust_app_event *event;
108 const struct ust_app_ht_key *key;
2106efa0 109 int ev_loglevel_value;
18eace3b
DG
110
111 assert(node);
112 assert(_key);
113
114 event = caa_container_of(node, struct ust_app_event, node.node);
115 key = _key;
2106efa0 116 ev_loglevel_value = event->attr.loglevel;
18eace3b 117
1af53eb5 118 /* Match the 4 elements of the key: name, filter, loglevel, exclusions */
18eace3b
DG
119
120 /* Event name */
121 if (strncmp(event->attr.name, key->name, sizeof(event->attr.name)) != 0) {
122 goto no_match;
123 }
124
125 /* Event loglevel. */
2106efa0 126 if (ev_loglevel_value != key->loglevel_type) {
025faf73 127 if (event->attr.loglevel_type == LTTNG_UST_LOGLEVEL_ALL
2106efa0
PP
128 && key->loglevel_type == 0 &&
129 ev_loglevel_value == -1) {
025faf73
DG
130 /*
131 * Match is accepted. This is because on event creation, the
132 * loglevel is set to -1 if the event loglevel type is ALL so 0 and
133 * -1 are accepted for this loglevel type since 0 is the one set by
134 * the API when receiving an enable event.
135 */
136 } else {
137 goto no_match;
138 }
18eace3b
DG
139 }
140
141 /* One of the filters is NULL, fail. */
142 if ((key->filter && !event->filter) || (!key->filter && event->filter)) {
143 goto no_match;
144 }
145
025faf73
DG
146 if (key->filter && event->filter) {
147 /* Both filters exists, check length followed by the bytecode. */
148 if (event->filter->len != key->filter->len ||
149 memcmp(event->filter->data, key->filter->data,
150 event->filter->len) != 0) {
151 goto no_match;
152 }
18eace3b
DG
153 }
154
1af53eb5
JI
155 /* One of the exclusions is NULL, fail. */
156 if ((key->exclusion && !event->exclusion) || (!key->exclusion && event->exclusion)) {
157 goto no_match;
158 }
159
160 if (key->exclusion && event->exclusion) {
161 /* Both exclusions exists, check count followed by the names. */
162 if (event->exclusion->count != key->exclusion->count ||
163 memcmp(event->exclusion->names, key->exclusion->names,
164 event->exclusion->count * LTTNG_UST_SYM_NAME_LEN) != 0) {
165 goto no_match;
166 }
167 }
168
169
025faf73 170 /* Match. */
18eace3b
DG
171 return 1;
172
173no_match:
174 return 0;
18eace3b
DG
175}
176
025faf73
DG
177/*
178 * Unique add of an ust app event in the given ht. This uses the custom
179 * ht_match_ust_app_event match function and the event name as hash.
180 */
d0b96690 181static void add_unique_ust_app_event(struct ust_app_channel *ua_chan,
18eace3b
DG
182 struct ust_app_event *event)
183{
184 struct cds_lfht_node *node_ptr;
185 struct ust_app_ht_key key;
d0b96690 186 struct lttng_ht *ht;
18eace3b 187
d0b96690
DG
188 assert(ua_chan);
189 assert(ua_chan->events);
18eace3b
DG
190 assert(event);
191
d0b96690 192 ht = ua_chan->events;
18eace3b
DG
193 key.name = event->attr.name;
194 key.filter = event->filter;
2106efa0 195 key.loglevel_type = event->attr.loglevel;
91c89f23 196 key.exclusion = event->exclusion;
18eace3b
DG
197
198 node_ptr = cds_lfht_add_unique(ht->ht,
199 ht->hash_fct(event->node.key, lttng_ht_seed),
200 ht_match_ust_app_event, &key, &event->node.node);
201 assert(node_ptr == &event->node.node);
202}
203
d88aee68
DG
204/*
205 * Close the notify socket from the given RCU head object. This MUST be called
206 * through a call_rcu().
207 */
208static void close_notify_sock_rcu(struct rcu_head *head)
209{
210 int ret;
211 struct ust_app_notify_sock_obj *obj =
212 caa_container_of(head, struct ust_app_notify_sock_obj, head);
213
214 /* Must have a valid fd here. */
215 assert(obj->fd >= 0);
216
217 ret = close(obj->fd);
218 if (ret) {
219 ERR("close notify sock %d RCU", obj->fd);
220 }
221 lttng_fd_put(LTTNG_FD_APPS, 1);
222
223 free(obj);
224}
225
7972aab2
DG
226/*
227 * Return the session registry according to the buffer type of the given
228 * session.
229 *
230 * A registry per UID object MUST exists before calling this function or else
231 * it assert() if not found. RCU read side lock must be acquired.
232 */
233static struct ust_registry_session *get_session_registry(
234 struct ust_app_session *ua_sess)
235{
236 struct ust_registry_session *registry = NULL;
237
238 assert(ua_sess);
239
240 switch (ua_sess->buffer_type) {
241 case LTTNG_BUFFER_PER_PID:
242 {
243 struct buffer_reg_pid *reg_pid = buffer_reg_pid_find(ua_sess->id);
244 if (!reg_pid) {
245 goto error;
246 }
247 registry = reg_pid->registry->reg.ust;
248 break;
249 }
250 case LTTNG_BUFFER_PER_UID:
251 {
252 struct buffer_reg_uid *reg_uid = buffer_reg_uid_find(
253 ua_sess->tracing_id, ua_sess->bits_per_long, ua_sess->uid);
254 if (!reg_uid) {
255 goto error;
256 }
257 registry = reg_uid->registry->reg.ust;
258 break;
259 }
260 default:
261 assert(0);
262 };
263
264error:
265 return registry;
266}
267
55cc08a6
DG
268/*
269 * Delete ust context safely. RCU read lock must be held before calling
270 * this function.
271 */
272static
fb45065e
MD
273void delete_ust_app_ctx(int sock, struct ust_app_ctx *ua_ctx,
274 struct ust_app *app)
55cc08a6 275{
ffe60014
DG
276 int ret;
277
278 assert(ua_ctx);
279
55cc08a6 280 if (ua_ctx->obj) {
fb45065e 281 pthread_mutex_lock(&app->sock_lock);
ffe60014 282 ret = ustctl_release_object(sock, ua_ctx->obj);
fb45065e 283 pthread_mutex_unlock(&app->sock_lock);
d0b96690
DG
284 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
285 ERR("UST app sock %d release ctx obj handle %d failed with ret %d",
286 sock, ua_ctx->obj->handle, ret);
ffe60014 287 }
55cc08a6
DG
288 free(ua_ctx->obj);
289 }
290 free(ua_ctx);
291}
292
d80a6244
DG
293/*
294 * Delete ust app event safely. RCU read lock must be held before calling
295 * this function.
296 */
8b366481 297static
fb45065e
MD
298void delete_ust_app_event(int sock, struct ust_app_event *ua_event,
299 struct ust_app *app)
d80a6244 300{
ffe60014
DG
301 int ret;
302
303 assert(ua_event);
304
53a80697 305 free(ua_event->filter);
951f0b71
JI
306 if (ua_event->exclusion != NULL)
307 free(ua_event->exclusion);
edb67388 308 if (ua_event->obj != NULL) {
fb45065e 309 pthread_mutex_lock(&app->sock_lock);
ffe60014 310 ret = ustctl_release_object(sock, ua_event->obj);
fb45065e 311 pthread_mutex_unlock(&app->sock_lock);
ffe60014
DG
312 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
313 ERR("UST app sock %d release event obj failed with ret %d",
314 sock, ret);
315 }
edb67388
DG
316 free(ua_event->obj);
317 }
d80a6244
DG
318 free(ua_event);
319}
320
321/*
7972aab2
DG
322 * Release ust data object of the given stream.
323 *
324 * Return 0 on success or else a negative value.
d80a6244 325 */
fb45065e
MD
326static int release_ust_app_stream(int sock, struct ust_app_stream *stream,
327 struct ust_app *app)
d80a6244 328{
7972aab2 329 int ret = 0;
ffe60014
DG
330
331 assert(stream);
332
8b366481 333 if (stream->obj) {
fb45065e 334 pthread_mutex_lock(&app->sock_lock);
ffe60014 335 ret = ustctl_release_object(sock, stream->obj);
fb45065e 336 pthread_mutex_unlock(&app->sock_lock);
ffe60014
DG
337 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
338 ERR("UST app sock %d release stream obj failed with ret %d",
339 sock, ret);
340 }
4063050c 341 lttng_fd_put(LTTNG_FD_APPS, 2);
8b366481
DG
342 free(stream->obj);
343 }
7972aab2
DG
344
345 return ret;
346}
347
348/*
349 * Delete ust app stream safely. RCU read lock must be held before calling
350 * this function.
351 */
352static
fb45065e
MD
353void delete_ust_app_stream(int sock, struct ust_app_stream *stream,
354 struct ust_app *app)
7972aab2
DG
355{
356 assert(stream);
357
fb45065e 358 (void) release_ust_app_stream(sock, stream, app);
84cd17c6 359 free(stream);
d80a6244
DG
360}
361
36b588ed
MD
362/*
363 * We need to execute ht_destroy outside of RCU read-side critical
0b2dc8df
MD
364 * section and outside of call_rcu thread, so we postpone its execution
365 * using ht_cleanup_push. It is simpler than to change the semantic of
366 * the many callers of delete_ust_app_session().
36b588ed
MD
367 */
368static
369void delete_ust_app_channel_rcu(struct rcu_head *head)
370{
371 struct ust_app_channel *ua_chan =
372 caa_container_of(head, struct ust_app_channel, rcu_head);
373
0b2dc8df
MD
374 ht_cleanup_push(ua_chan->ctx);
375 ht_cleanup_push(ua_chan->events);
36b588ed
MD
376 free(ua_chan);
377}
378
fb83fe64
JD
379/*
380 * Extract the lost packet or discarded events counter when the channel is
381 * being deleted and store the value in the parent channel so we can
382 * access it from lttng list and at stop/destroy.
82cac6d2
JG
383 *
384 * The session list lock must be held by the caller.
fb83fe64
JD
385 */
386static
387void save_per_pid_lost_discarded_counters(struct ust_app_channel *ua_chan)
388{
389 uint64_t discarded = 0, lost = 0;
390 struct ltt_session *session;
391 struct ltt_ust_channel *uchan;
392
393 if (ua_chan->attr.type != LTTNG_UST_CHAN_PER_CPU) {
394 return;
395 }
396
397 rcu_read_lock();
398 session = session_find_by_id(ua_chan->session->tracing_id);
d68ec974
JG
399 if (!session || !session->ust_session) {
400 /*
401 * Not finding the session is not an error because there are
402 * multiple ways the channels can be torn down.
403 *
404 * 1) The session daemon can initiate the destruction of the
405 * ust app session after receiving a destroy command or
406 * during its shutdown/teardown.
407 * 2) The application, since we are in per-pid tracing, is
408 * unregistering and tearing down its ust app session.
409 *
410 * Both paths are protected by the session list lock which
411 * ensures that the accounting of lost packets and discarded
412 * events is done exactly once. The session is then unpublished
413 * from the session list, resulting in this condition.
414 */
fb83fe64
JD
415 goto end;
416 }
417
418 if (ua_chan->attr.overwrite) {
419 consumer_get_lost_packets(ua_chan->session->tracing_id,
420 ua_chan->key, session->ust_session->consumer,
421 &lost);
422 } else {
423 consumer_get_discarded_events(ua_chan->session->tracing_id,
424 ua_chan->key, session->ust_session->consumer,
425 &discarded);
426 }
427 uchan = trace_ust_find_channel_by_name(
428 session->ust_session->domain_global.channels,
429 ua_chan->name);
430 if (!uchan) {
431 ERR("Missing UST channel to store discarded counters");
432 goto end;
433 }
434
435 uchan->per_pid_closed_app_discarded += discarded;
436 uchan->per_pid_closed_app_lost += lost;
437
438end:
439 rcu_read_unlock();
440}
441
d80a6244
DG
442/*
443 * Delete ust app channel safely. RCU read lock must be held before calling
444 * this function.
82cac6d2
JG
445 *
446 * The session list lock must be held by the caller.
d80a6244 447 */
8b366481 448static
d0b96690
DG
449void delete_ust_app_channel(int sock, struct ust_app_channel *ua_chan,
450 struct ust_app *app)
d80a6244
DG
451{
452 int ret;
bec39940 453 struct lttng_ht_iter iter;
d80a6244 454 struct ust_app_event *ua_event;
55cc08a6 455 struct ust_app_ctx *ua_ctx;
030a66fa 456 struct ust_app_stream *stream, *stmp;
7972aab2 457 struct ust_registry_session *registry;
d80a6244 458
ffe60014
DG
459 assert(ua_chan);
460
461 DBG3("UST app deleting channel %s", ua_chan->name);
462
55cc08a6 463 /* Wipe stream */
d80a6244 464 cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
84cd17c6 465 cds_list_del(&stream->list);
fb45065e 466 delete_ust_app_stream(sock, stream, app);
d80a6244
DG
467 }
468
55cc08a6 469 /* Wipe context */
bec39940 470 cds_lfht_for_each_entry(ua_chan->ctx->ht, &iter.iter, ua_ctx, node.node) {
31746f93 471 cds_list_del(&ua_ctx->list);
bec39940 472 ret = lttng_ht_del(ua_chan->ctx, &iter);
55cc08a6 473 assert(!ret);
fb45065e 474 delete_ust_app_ctx(sock, ua_ctx, app);
55cc08a6 475 }
d80a6244 476
55cc08a6 477 /* Wipe events */
bec39940
DG
478 cds_lfht_for_each_entry(ua_chan->events->ht, &iter.iter, ua_event,
479 node.node) {
480 ret = lttng_ht_del(ua_chan->events, &iter);
525b0740 481 assert(!ret);
fb45065e 482 delete_ust_app_event(sock, ua_event, app);
d80a6244 483 }
edb67388 484
c8335706
MD
485 if (ua_chan->session->buffer_type == LTTNG_BUFFER_PER_PID) {
486 /* Wipe and free registry from session registry. */
487 registry = get_session_registry(ua_chan->session);
488 if (registry) {
e9404c27 489 ust_registry_channel_del_free(registry, ua_chan->key,
e38d96f9
MD
490 sock >= 0);
491 }
492 if (sock >= 0) {
493 save_per_pid_lost_discarded_counters(ua_chan);
c8335706 494 }
7972aab2 495 }
d0b96690 496
edb67388 497 if (ua_chan->obj != NULL) {
d0b96690
DG
498 /* Remove channel from application UST object descriptor. */
499 iter.iter.node = &ua_chan->ust_objd_node.node;
c6e62271
DG
500 ret = lttng_ht_del(app->ust_objd, &iter);
501 assert(!ret);
fb45065e 502 pthread_mutex_lock(&app->sock_lock);
ffe60014 503 ret = ustctl_release_object(sock, ua_chan->obj);
fb45065e 504 pthread_mutex_unlock(&app->sock_lock);
ffe60014
DG
505 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
506 ERR("UST app sock %d release channel obj failed with ret %d",
507 sock, ret);
508 }
7972aab2 509 lttng_fd_put(LTTNG_FD_APPS, 1);
edb67388
DG
510 free(ua_chan->obj);
511 }
36b588ed 512 call_rcu(&ua_chan->rcu_head, delete_ust_app_channel_rcu);
d80a6244
DG
513}
514
fb45065e
MD
515int ust_app_register_done(struct ust_app *app)
516{
517 int ret;
518
519 pthread_mutex_lock(&app->sock_lock);
520 ret = ustctl_register_done(app->sock);
521 pthread_mutex_unlock(&app->sock_lock);
522 return ret;
523}
524
525int ust_app_release_object(struct ust_app *app, struct lttng_ust_object_data *data)
526{
527 int ret, sock;
528
529 if (app) {
530 pthread_mutex_lock(&app->sock_lock);
531 sock = app->sock;
532 } else {
533 sock = -1;
534 }
535 ret = ustctl_release_object(sock, data);
536 if (app) {
537 pthread_mutex_unlock(&app->sock_lock);
538 }
539 return ret;
540}
541
331744e3 542/*
1b532a60
DG
543 * Push metadata to consumer socket.
544 *
dc2bbdae
MD
545 * RCU read-side lock must be held to guarantee existance of socket.
546 * Must be called with the ust app session lock held.
547 * Must be called with the registry lock held.
331744e3
JD
548 *
549 * On success, return the len of metadata pushed or else a negative value.
2c57e06d
MD
550 * Returning a -EPIPE return value means we could not send the metadata,
551 * but it can be caused by recoverable errors (e.g. the application has
552 * terminated concurrently).
331744e3
JD
553 */
554ssize_t ust_app_push_metadata(struct ust_registry_session *registry,
555 struct consumer_socket *socket, int send_zero_data)
556{
557 int ret;
558 char *metadata_str = NULL;
c585821b 559 size_t len, offset, new_metadata_len_sent;
331744e3 560 ssize_t ret_val;
93ec662e 561 uint64_t metadata_key, metadata_version;
331744e3
JD
562
563 assert(registry);
564 assert(socket);
1b532a60 565
c585821b
MD
566 metadata_key = registry->metadata_key;
567
ce34fcd0 568 /*
dc2bbdae
MD
569 * Means that no metadata was assigned to the session. This can
570 * happens if no start has been done previously.
ce34fcd0 571 */
c585821b 572 if (!metadata_key) {
ce34fcd0
MD
573 return 0;
574 }
575
331744e3
JD
576 offset = registry->metadata_len_sent;
577 len = registry->metadata_len - registry->metadata_len_sent;
c585821b 578 new_metadata_len_sent = registry->metadata_len;
93ec662e 579 metadata_version = registry->metadata_version;
331744e3
JD
580 if (len == 0) {
581 DBG3("No metadata to push for metadata key %" PRIu64,
582 registry->metadata_key);
583 ret_val = len;
584 if (send_zero_data) {
585 DBG("No metadata to push");
586 goto push_data;
587 }
588 goto end;
589 }
590
591 /* Allocate only what we have to send. */
592 metadata_str = zmalloc(len);
593 if (!metadata_str) {
594 PERROR("zmalloc ust app metadata string");
595 ret_val = -ENOMEM;
596 goto error;
597 }
c585821b 598 /* Copy what we haven't sent out. */
331744e3 599 memcpy(metadata_str, registry->metadata + offset, len);
331744e3
JD
600
601push_data:
c585821b
MD
602 pthread_mutex_unlock(&registry->lock);
603 /*
604 * We need to unlock the registry while we push metadata to
605 * break a circular dependency between the consumerd metadata
606 * lock and the sessiond registry lock. Indeed, pushing metadata
607 * to the consumerd awaits that it gets pushed all the way to
608 * relayd, but doing so requires grabbing the metadata lock. If
609 * a concurrent metadata request is being performed by
610 * consumerd, this can try to grab the registry lock on the
611 * sessiond while holding the metadata lock on the consumer
612 * daemon. Those push and pull schemes are performed on two
613 * different bidirectionnal communication sockets.
614 */
615 ret = consumer_push_metadata(socket, metadata_key,
93ec662e 616 metadata_str, len, offset, metadata_version);
c585821b 617 pthread_mutex_lock(&registry->lock);
331744e3 618 if (ret < 0) {
000baf6a 619 /*
dc2bbdae
MD
620 * There is an acceptable race here between the registry
621 * metadata key assignment and the creation on the
622 * consumer. The session daemon can concurrently push
623 * metadata for this registry while being created on the
624 * consumer since the metadata key of the registry is
625 * assigned *before* it is setup to avoid the consumer
626 * to ask for metadata that could possibly be not found
627 * in the session daemon.
000baf6a 628 *
dc2bbdae
MD
629 * The metadata will get pushed either by the session
630 * being stopped or the consumer requesting metadata if
631 * that race is triggered.
000baf6a
DG
632 */
633 if (ret == -LTTCOMM_CONSUMERD_CHANNEL_FAIL) {
634 ret = 0;
c585821b
MD
635 } else {
636 ERR("Error pushing metadata to consumer");
000baf6a 637 }
331744e3
JD
638 ret_val = ret;
639 goto error_push;
c585821b
MD
640 } else {
641 /*
642 * Metadata may have been concurrently pushed, since
643 * we're not holding the registry lock while pushing to
644 * consumer. This is handled by the fact that we send
645 * the metadata content, size, and the offset at which
646 * that metadata belongs. This may arrive out of order
647 * on the consumer side, and the consumer is able to
648 * deal with overlapping fragments. The consumer
649 * supports overlapping fragments, which must be
650 * contiguous starting from offset 0. We keep the
651 * largest metadata_len_sent value of the concurrent
652 * send.
653 */
654 registry->metadata_len_sent =
655 max_t(size_t, registry->metadata_len_sent,
656 new_metadata_len_sent);
331744e3 657 }
331744e3
JD
658 free(metadata_str);
659 return len;
660
661end:
662error:
ce34fcd0
MD
663 if (ret_val) {
664 /*
dc2bbdae
MD
665 * On error, flag the registry that the metadata is
666 * closed. We were unable to push anything and this
667 * means that either the consumer is not responding or
668 * the metadata cache has been destroyed on the
669 * consumer.
ce34fcd0
MD
670 */
671 registry->metadata_closed = 1;
672 }
331744e3
JD
673error_push:
674 free(metadata_str);
675 return ret_val;
676}
677
d88aee68 678/*
ce34fcd0 679 * For a given application and session, push metadata to consumer.
331744e3
JD
680 * Either sock or consumer is required : if sock is NULL, the default
681 * socket to send the metadata is retrieved from consumer, if sock
682 * is not NULL we use it to send the metadata.
ce34fcd0 683 * RCU read-side lock must be held while calling this function,
dc2bbdae
MD
684 * therefore ensuring existance of registry. It also ensures existance
685 * of socket throughout this function.
d88aee68
DG
686 *
687 * Return 0 on success else a negative error.
2c57e06d
MD
688 * Returning a -EPIPE return value means we could not send the metadata,
689 * but it can be caused by recoverable errors (e.g. the application has
690 * terminated concurrently).
d88aee68 691 */
7972aab2
DG
692static int push_metadata(struct ust_registry_session *registry,
693 struct consumer_output *consumer)
d88aee68 694{
331744e3
JD
695 int ret_val;
696 ssize_t ret;
d88aee68
DG
697 struct consumer_socket *socket;
698
7972aab2
DG
699 assert(registry);
700 assert(consumer);
701
ce34fcd0 702 pthread_mutex_lock(&registry->lock);
ce34fcd0 703 if (registry->metadata_closed) {
dc2bbdae
MD
704 ret_val = -EPIPE;
705 goto error;
d88aee68
DG
706 }
707
d88aee68 708 /* Get consumer socket to use to push the metadata.*/
7972aab2
DG
709 socket = consumer_find_socket_by_bitness(registry->bits_per_long,
710 consumer);
d88aee68 711 if (!socket) {
331744e3 712 ret_val = -1;
ce34fcd0 713 goto error;
d88aee68
DG
714 }
715
331744e3 716 ret = ust_app_push_metadata(registry, socket, 0);
d88aee68 717 if (ret < 0) {
331744e3 718 ret_val = ret;
ce34fcd0 719 goto error;
d88aee68 720 }
dc2bbdae 721 pthread_mutex_unlock(&registry->lock);
d88aee68
DG
722 return 0;
723
ce34fcd0 724error:
dc2bbdae 725 pthread_mutex_unlock(&registry->lock);
331744e3 726 return ret_val;
d88aee68
DG
727}
728
729/*
730 * Send to the consumer a close metadata command for the given session. Once
731 * done, the metadata channel is deleted and the session metadata pointer is
dc2bbdae 732 * nullified. The session lock MUST be held unless the application is
d88aee68
DG
733 * in the destroy path.
734 *
735 * Return 0 on success else a negative value.
736 */
7972aab2
DG
737static int close_metadata(struct ust_registry_session *registry,
738 struct consumer_output *consumer)
d88aee68
DG
739{
740 int ret;
741 struct consumer_socket *socket;
742
7972aab2
DG
743 assert(registry);
744 assert(consumer);
d88aee68 745
7972aab2
DG
746 rcu_read_lock();
747
ce34fcd0
MD
748 pthread_mutex_lock(&registry->lock);
749
7972aab2 750 if (!registry->metadata_key || registry->metadata_closed) {
d88aee68 751 ret = 0;
1b532a60 752 goto end;
d88aee68
DG
753 }
754
d88aee68 755 /* Get consumer socket to use to push the metadata.*/
7972aab2
DG
756 socket = consumer_find_socket_by_bitness(registry->bits_per_long,
757 consumer);
d88aee68
DG
758 if (!socket) {
759 ret = -1;
7972aab2 760 goto error;
d88aee68
DG
761 }
762
7972aab2 763 ret = consumer_close_metadata(socket, registry->metadata_key);
d88aee68 764 if (ret < 0) {
7972aab2 765 goto error;
d88aee68
DG
766 }
767
d88aee68 768error:
1b532a60
DG
769 /*
770 * Metadata closed. Even on error this means that the consumer is not
771 * responding or not found so either way a second close should NOT be emit
772 * for this registry.
773 */
774 registry->metadata_closed = 1;
775end:
ce34fcd0 776 pthread_mutex_unlock(&registry->lock);
7972aab2 777 rcu_read_unlock();
d88aee68
DG
778 return ret;
779}
780
36b588ed
MD
781/*
782 * We need to execute ht_destroy outside of RCU read-side critical
0b2dc8df
MD
783 * section and outside of call_rcu thread, so we postpone its execution
784 * using ht_cleanup_push. It is simpler than to change the semantic of
785 * the many callers of delete_ust_app_session().
36b588ed
MD
786 */
787static
788void delete_ust_app_session_rcu(struct rcu_head *head)
789{
790 struct ust_app_session *ua_sess =
791 caa_container_of(head, struct ust_app_session, rcu_head);
792
0b2dc8df 793 ht_cleanup_push(ua_sess->channels);
36b588ed
MD
794 free(ua_sess);
795}
796
d80a6244
DG
797/*
798 * Delete ust app session safely. RCU read lock must be held before calling
799 * this function.
82cac6d2
JG
800 *
801 * The session list lock must be held by the caller.
d80a6244 802 */
8b366481 803static
d0b96690
DG
804void delete_ust_app_session(int sock, struct ust_app_session *ua_sess,
805 struct ust_app *app)
d80a6244
DG
806{
807 int ret;
bec39940 808 struct lttng_ht_iter iter;
d80a6244 809 struct ust_app_channel *ua_chan;
7972aab2 810 struct ust_registry_session *registry;
d80a6244 811
d88aee68
DG
812 assert(ua_sess);
813
1b532a60
DG
814 pthread_mutex_lock(&ua_sess->lock);
815
b161602a
MD
816 assert(!ua_sess->deleted);
817 ua_sess->deleted = true;
818
7972aab2 819 registry = get_session_registry(ua_sess);
fad1ed2f 820 /* Registry can be null on error path during initialization. */
ce34fcd0 821 if (registry) {
d88aee68 822 /* Push metadata for application before freeing the application. */
7972aab2 823 (void) push_metadata(registry, ua_sess->consumer);
d88aee68 824
7972aab2
DG
825 /*
826 * Don't ask to close metadata for global per UID buffers. Close
1b532a60
DG
827 * metadata only on destroy trace session in this case. Also, the
828 * previous push metadata could have flag the metadata registry to
829 * close so don't send a close command if closed.
7972aab2 830 */
ce34fcd0 831 if (ua_sess->buffer_type != LTTNG_BUFFER_PER_UID) {
7972aab2
DG
832 /* And ask to close it for this session registry. */
833 (void) close_metadata(registry, ua_sess->consumer);
834 }
d80a6244
DG
835 }
836
bec39940
DG
837 cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
838 node.node) {
839 ret = lttng_ht_del(ua_sess->channels, &iter);
525b0740 840 assert(!ret);
d0b96690 841 delete_ust_app_channel(sock, ua_chan, app);
d80a6244 842 }
d80a6244 843
7972aab2
DG
844 /* In case of per PID, the registry is kept in the session. */
845 if (ua_sess->buffer_type == LTTNG_BUFFER_PER_PID) {
846 struct buffer_reg_pid *reg_pid = buffer_reg_pid_find(ua_sess->id);
847 if (reg_pid) {
fad1ed2f
JR
848 /*
849 * Registry can be null on error path during
850 * initialization.
851 */
7972aab2
DG
852 buffer_reg_pid_remove(reg_pid);
853 buffer_reg_pid_destroy(reg_pid);
854 }
855 }
d0b96690 856
aee6bafd 857 if (ua_sess->handle != -1) {
fb45065e 858 pthread_mutex_lock(&app->sock_lock);
ffe60014 859 ret = ustctl_release_handle(sock, ua_sess->handle);
fb45065e 860 pthread_mutex_unlock(&app->sock_lock);
ffe60014
DG
861 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
862 ERR("UST app sock %d release session handle failed with ret %d",
863 sock, ret);
864 }
10b56aef
MD
865 /* Remove session from application UST object descriptor. */
866 iter.iter.node = &ua_sess->ust_objd_node.node;
867 ret = lttng_ht_del(app->ust_sessions_objd, &iter);
868 assert(!ret);
aee6bafd 869 }
10b56aef 870
1b532a60
DG
871 pthread_mutex_unlock(&ua_sess->lock);
872
6addfa37
MD
873 consumer_output_put(ua_sess->consumer);
874
36b588ed 875 call_rcu(&ua_sess->rcu_head, delete_ust_app_session_rcu);
d80a6244 876}
91d76f53
DG
877
878/*
284d8f55
DG
879 * Delete a traceable application structure from the global list. Never call
880 * this function outside of a call_rcu call.
36b588ed
MD
881 *
882 * RCU read side lock should _NOT_ be held when calling this function.
91d76f53 883 */
8b366481
DG
884static
885void delete_ust_app(struct ust_app *app)
91d76f53 886{
8b366481 887 int ret, sock;
d42f20df 888 struct ust_app_session *ua_sess, *tmp_ua_sess;
44d3bd01 889
82cac6d2
JG
890 /*
891 * The session list lock must be held during this function to guarantee
892 * the existence of ua_sess.
893 */
894 session_lock_list();
d80a6244 895 /* Delete ust app sessions info */
852d0037
DG
896 sock = app->sock;
897 app->sock = -1;
d80a6244 898
8b366481 899 /* Wipe sessions */
d42f20df
DG
900 cds_list_for_each_entry_safe(ua_sess, tmp_ua_sess, &app->teardown_head,
901 teardown_node) {
902 /* Free every object in the session and the session. */
36b588ed 903 rcu_read_lock();
d0b96690 904 delete_ust_app_session(sock, ua_sess, app);
36b588ed 905 rcu_read_unlock();
d80a6244 906 }
36b588ed 907
0b2dc8df 908 ht_cleanup_push(app->sessions);
10b56aef 909 ht_cleanup_push(app->ust_sessions_objd);
0b2dc8df 910 ht_cleanup_push(app->ust_objd);
d80a6244 911
6414a713 912 /*
852d0037
DG
913 * Wait until we have deleted the application from the sock hash table
914 * before closing this socket, otherwise an application could re-use the
915 * socket ID and race with the teardown, using the same hash table entry.
916 *
917 * It's OK to leave the close in call_rcu. We want it to stay unique for
918 * all RCU readers that could run concurrently with unregister app,
919 * therefore we _need_ to only close that socket after a grace period. So
920 * it should stay in this RCU callback.
921 *
922 * This close() is a very important step of the synchronization model so
923 * every modification to this function must be carefully reviewed.
6414a713 924 */
799e2c4f
MD
925 ret = close(sock);
926 if (ret) {
927 PERROR("close");
928 }
4063050c 929 lttng_fd_put(LTTNG_FD_APPS, 1);
d80a6244 930
852d0037 931 DBG2("UST app pid %d deleted", app->pid);
284d8f55 932 free(app);
82cac6d2 933 session_unlock_list();
099e26bd
DG
934}
935
936/*
f6a9efaa 937 * URCU intermediate call to delete an UST app.
099e26bd 938 */
8b366481
DG
939static
940void delete_ust_app_rcu(struct rcu_head *head)
099e26bd 941{
bec39940
DG
942 struct lttng_ht_node_ulong *node =
943 caa_container_of(head, struct lttng_ht_node_ulong, head);
f6a9efaa 944 struct ust_app *app =
852d0037 945 caa_container_of(node, struct ust_app, pid_n);
f6a9efaa 946
852d0037 947 DBG3("Call RCU deleting app PID %d", app->pid);
f6a9efaa 948 delete_ust_app(app);
099e26bd
DG
949}
950
ffe60014
DG
951/*
952 * Delete the session from the application ht and delete the data structure by
953 * freeing every object inside and releasing them.
82cac6d2
JG
954 *
955 * The session list lock must be held by the caller.
ffe60014 956 */
d0b96690 957static void destroy_app_session(struct ust_app *app,
ffe60014
DG
958 struct ust_app_session *ua_sess)
959{
960 int ret;
961 struct lttng_ht_iter iter;
962
963 assert(app);
964 assert(ua_sess);
965
966 iter.iter.node = &ua_sess->node.node;
967 ret = lttng_ht_del(app->sessions, &iter);
968 if (ret) {
969 /* Already scheduled for teardown. */
970 goto end;
971 }
972
973 /* Once deleted, free the data structure. */
d0b96690 974 delete_ust_app_session(app->sock, ua_sess, app);
ffe60014
DG
975
976end:
977 return;
978}
979
8b366481
DG
980/*
981 * Alloc new UST app session.
982 */
983static
40bbd087 984struct ust_app_session *alloc_ust_app_session(void)
8b366481
DG
985{
986 struct ust_app_session *ua_sess;
987
988 /* Init most of the default value by allocating and zeroing */
989 ua_sess = zmalloc(sizeof(struct ust_app_session));
990 if (ua_sess == NULL) {
991 PERROR("malloc");
ffe60014 992 goto error_free;
8b366481
DG
993 }
994
995 ua_sess->handle = -1;
bec39940 996 ua_sess->channels = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
ad7a9107 997 ua_sess->metadata_attr.type = LTTNG_UST_CHAN_METADATA;
84ad93e8 998 pthread_mutex_init(&ua_sess->lock, NULL);
ad7a9107 999
8b366481
DG
1000 return ua_sess;
1001
ffe60014 1002error_free:
8b366481
DG
1003 return NULL;
1004}
1005
1006/*
1007 * Alloc new UST app channel.
1008 */
1009static
1010struct ust_app_channel *alloc_ust_app_channel(char *name,
d0b96690 1011 struct ust_app_session *ua_sess,
ffe60014 1012 struct lttng_ust_channel_attr *attr)
8b366481
DG
1013{
1014 struct ust_app_channel *ua_chan;
1015
1016 /* Init most of the default value by allocating and zeroing */
1017 ua_chan = zmalloc(sizeof(struct ust_app_channel));
1018 if (ua_chan == NULL) {
1019 PERROR("malloc");
1020 goto error;
1021 }
1022
1023 /* Setup channel name */
1024 strncpy(ua_chan->name, name, sizeof(ua_chan->name));
1025 ua_chan->name[sizeof(ua_chan->name) - 1] = '\0';
1026
1027 ua_chan->enabled = 1;
1028 ua_chan->handle = -1;
45893984 1029 ua_chan->session = ua_sess;
ffe60014 1030 ua_chan->key = get_next_channel_key();
bec39940
DG
1031 ua_chan->ctx = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
1032 ua_chan->events = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
1033 lttng_ht_node_init_str(&ua_chan->node, ua_chan->name);
8b366481
DG
1034
1035 CDS_INIT_LIST_HEAD(&ua_chan->streams.head);
31746f93 1036 CDS_INIT_LIST_HEAD(&ua_chan->ctx_list);
8b366481
DG
1037
1038 /* Copy attributes */
1039 if (attr) {
ffe60014 1040 /* Translate from lttng_ust_channel to ustctl_consumer_channel_attr. */
2fe6e7f5
DG
1041 ua_chan->attr.subbuf_size = attr->subbuf_size;
1042 ua_chan->attr.num_subbuf = attr->num_subbuf;
1043 ua_chan->attr.overwrite = attr->overwrite;
1044 ua_chan->attr.switch_timer_interval = attr->switch_timer_interval;
1045 ua_chan->attr.read_timer_interval = attr->read_timer_interval;
1046 ua_chan->attr.output = attr->output;
491d1539 1047 ua_chan->attr.blocking_timeout = attr->u.s.blocking_timeout;
8b366481 1048 }
ffe60014
DG
1049 /* By default, the channel is a per cpu channel. */
1050 ua_chan->attr.type = LTTNG_UST_CHAN_PER_CPU;
8b366481
DG
1051
1052 DBG3("UST app channel %s allocated", ua_chan->name);
1053
1054 return ua_chan;
1055
1056error:
1057 return NULL;
1058}
1059
37f1c236
DG
1060/*
1061 * Allocate and initialize a UST app stream.
1062 *
1063 * Return newly allocated stream pointer or NULL on error.
1064 */
ffe60014 1065struct ust_app_stream *ust_app_alloc_stream(void)
37f1c236
DG
1066{
1067 struct ust_app_stream *stream = NULL;
1068
1069 stream = zmalloc(sizeof(*stream));
1070 if (stream == NULL) {
1071 PERROR("zmalloc ust app stream");
1072 goto error;
1073 }
1074
1075 /* Zero could be a valid value for a handle so flag it to -1. */
1076 stream->handle = -1;
1077
1078error:
1079 return stream;
1080}
1081
8b366481
DG
1082/*
1083 * Alloc new UST app event.
1084 */
1085static
1086struct ust_app_event *alloc_ust_app_event(char *name,
1087 struct lttng_ust_event *attr)
1088{
1089 struct ust_app_event *ua_event;
1090
1091 /* Init most of the default value by allocating and zeroing */
1092 ua_event = zmalloc(sizeof(struct ust_app_event));
1093 if (ua_event == NULL) {
1094 PERROR("malloc");
1095 goto error;
1096 }
1097
1098 ua_event->enabled = 1;
1099 strncpy(ua_event->name, name, sizeof(ua_event->name));
1100 ua_event->name[sizeof(ua_event->name) - 1] = '\0';
bec39940 1101 lttng_ht_node_init_str(&ua_event->node, ua_event->name);
8b366481
DG
1102
1103 /* Copy attributes */
1104 if (attr) {
1105 memcpy(&ua_event->attr, attr, sizeof(ua_event->attr));
1106 }
1107
1108 DBG3("UST app event %s allocated", ua_event->name);
1109
1110 return ua_event;
1111
1112error:
1113 return NULL;
1114}
1115
1116/*
1117 * Alloc new UST app context.
1118 */
1119static
bdf64013 1120struct ust_app_ctx *alloc_ust_app_ctx(struct lttng_ust_context_attr *uctx)
8b366481
DG
1121{
1122 struct ust_app_ctx *ua_ctx;
1123
1124 ua_ctx = zmalloc(sizeof(struct ust_app_ctx));
1125 if (ua_ctx == NULL) {
1126 goto error;
1127 }
1128
31746f93
DG
1129 CDS_INIT_LIST_HEAD(&ua_ctx->list);
1130
8b366481
DG
1131 if (uctx) {
1132 memcpy(&ua_ctx->ctx, uctx, sizeof(ua_ctx->ctx));
bdf64013
JG
1133 if (uctx->ctx == LTTNG_UST_CONTEXT_APP_CONTEXT) {
1134 char *provider_name = NULL, *ctx_name = NULL;
1135
1136 provider_name = strdup(uctx->u.app_ctx.provider_name);
1137 ctx_name = strdup(uctx->u.app_ctx.ctx_name);
1138 if (!provider_name || !ctx_name) {
1139 free(provider_name);
1140 free(ctx_name);
1141 goto error;
1142 }
1143
1144 ua_ctx->ctx.u.app_ctx.provider_name = provider_name;
1145 ua_ctx->ctx.u.app_ctx.ctx_name = ctx_name;
1146 }
8b366481
DG
1147 }
1148
1149 DBG3("UST app context %d allocated", ua_ctx->ctx.ctx);
8b366481 1150 return ua_ctx;
bdf64013
JG
1151error:
1152 free(ua_ctx);
1153 return NULL;
8b366481
DG
1154}
1155
025faf73
DG
1156/*
1157 * Allocate a filter and copy the given original filter.
1158 *
1159 * Return allocated filter or NULL on error.
1160 */
51755dc8
JG
1161static struct lttng_filter_bytecode *copy_filter_bytecode(
1162 struct lttng_filter_bytecode *orig_f)
025faf73 1163{
51755dc8 1164 struct lttng_filter_bytecode *filter = NULL;
025faf73
DG
1165
1166 /* Copy filter bytecode */
1167 filter = zmalloc(sizeof(*filter) + orig_f->len);
1168 if (!filter) {
51755dc8 1169 PERROR("zmalloc alloc filter bytecode");
025faf73
DG
1170 goto error;
1171 }
1172
1173 memcpy(filter, orig_f, sizeof(*filter) + orig_f->len);
1174
1175error:
1176 return filter;
1177}
1178
51755dc8
JG
1179/*
1180 * Create a liblttng-ust filter bytecode from given bytecode.
1181 *
1182 * Return allocated filter or NULL on error.
1183 */
1184static struct lttng_ust_filter_bytecode *create_ust_bytecode_from_bytecode(
1185 struct lttng_filter_bytecode *orig_f)
1186{
1187 struct lttng_ust_filter_bytecode *filter = NULL;
1188
1189 /* Copy filter bytecode */
1190 filter = zmalloc(sizeof(*filter) + orig_f->len);
1191 if (!filter) {
1192 PERROR("zmalloc alloc ust filter bytecode");
1193 goto error;
1194 }
1195
1196 assert(sizeof(struct lttng_filter_bytecode) ==
1197 sizeof(struct lttng_ust_filter_bytecode));
1198 memcpy(filter, orig_f, sizeof(*filter) + orig_f->len);
1199error:
1200 return filter;
1201}
1202
099e26bd 1203/*
421cb601
DG
1204 * Find an ust_app using the sock and return it. RCU read side lock must be
1205 * held before calling this helper function.
099e26bd 1206 */
f20baf8e 1207struct ust_app *ust_app_find_by_sock(int sock)
099e26bd 1208{
bec39940 1209 struct lttng_ht_node_ulong *node;
bec39940 1210 struct lttng_ht_iter iter;
f6a9efaa 1211
852d0037 1212 lttng_ht_lookup(ust_app_ht_by_sock, (void *)((unsigned long) sock), &iter);
bec39940 1213 node = lttng_ht_iter_get_node_ulong(&iter);
f6a9efaa
DG
1214 if (node == NULL) {
1215 DBG2("UST app find by sock %d not found", sock);
f6a9efaa
DG
1216 goto error;
1217 }
852d0037
DG
1218
1219 return caa_container_of(node, struct ust_app, sock_n);
f6a9efaa
DG
1220
1221error:
1222 return NULL;
099e26bd
DG
1223}
1224
d0b96690
DG
1225/*
1226 * Find an ust_app using the notify sock and return it. RCU read side lock must
1227 * be held before calling this helper function.
1228 */
1229static struct ust_app *find_app_by_notify_sock(int sock)
1230{
1231 struct lttng_ht_node_ulong *node;
1232 struct lttng_ht_iter iter;
1233
1234 lttng_ht_lookup(ust_app_ht_by_notify_sock, (void *)((unsigned long) sock),
1235 &iter);
1236 node = lttng_ht_iter_get_node_ulong(&iter);
1237 if (node == NULL) {
1238 DBG2("UST app find by notify sock %d not found", sock);
1239 goto error;
1240 }
1241
1242 return caa_container_of(node, struct ust_app, notify_sock_n);
1243
1244error:
1245 return NULL;
1246}
1247
025faf73
DG
1248/*
1249 * Lookup for an ust app event based on event name, filter bytecode and the
1250 * event loglevel.
1251 *
1252 * Return an ust_app_event object or NULL on error.
1253 */
18eace3b 1254static struct ust_app_event *find_ust_app_event(struct lttng_ht *ht,
2106efa0
PP
1255 char *name, struct lttng_filter_bytecode *filter,
1256 int loglevel_value,
39c5a3a7 1257 const struct lttng_event_exclusion *exclusion)
18eace3b
DG
1258{
1259 struct lttng_ht_iter iter;
1260 struct lttng_ht_node_str *node;
1261 struct ust_app_event *event = NULL;
1262 struct ust_app_ht_key key;
18eace3b
DG
1263
1264 assert(name);
1265 assert(ht);
1266
1267 /* Setup key for event lookup. */
1268 key.name = name;
1269 key.filter = filter;
2106efa0 1270 key.loglevel_type = loglevel_value;
39c5a3a7 1271 /* lttng_event_exclusion and lttng_ust_event_exclusion structures are similar */
51755dc8 1272 key.exclusion = exclusion;
18eace3b 1273
025faf73
DG
1274 /* Lookup using the event name as hash and a custom match fct. */
1275 cds_lfht_lookup(ht->ht, ht->hash_fct((void *) name, lttng_ht_seed),
1276 ht_match_ust_app_event, &key, &iter.iter);
18eace3b
DG
1277 node = lttng_ht_iter_get_node_str(&iter);
1278 if (node == NULL) {
1279 goto end;
1280 }
1281
1282 event = caa_container_of(node, struct ust_app_event, node);
1283
1284end:
18eace3b
DG
1285 return event;
1286}
1287
55cc08a6
DG
1288/*
1289 * Create the channel context on the tracer.
d0b96690
DG
1290 *
1291 * Called with UST app session lock held.
55cc08a6
DG
1292 */
1293static
1294int create_ust_channel_context(struct ust_app_channel *ua_chan,
1295 struct ust_app_ctx *ua_ctx, struct ust_app *app)
1296{
1297 int ret;
1298
840cb59c 1299 health_code_update();
86acf0da 1300
fb45065e 1301 pthread_mutex_lock(&app->sock_lock);
852d0037 1302 ret = ustctl_add_context(app->sock, &ua_ctx->ctx,
55cc08a6 1303 ua_chan->obj, &ua_ctx->obj);
fb45065e 1304 pthread_mutex_unlock(&app->sock_lock);
55cc08a6 1305 if (ret < 0) {
ffe60014
DG
1306 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1307 ERR("UST app create channel context failed for app (pid: %d) "
1308 "with ret %d", app->pid, ret);
1309 } else {
3757b385
DG
1310 /*
1311 * This is normal behavior, an application can die during the
1312 * creation process. Don't report an error so the execution can
1313 * continue normally.
1314 */
1315 ret = 0;
ffe60014
DG
1316 DBG3("UST app disable event failed. Application is dead.");
1317 }
55cc08a6
DG
1318 goto error;
1319 }
1320
1321 ua_ctx->handle = ua_ctx->obj->handle;
1322
d0b96690
DG
1323 DBG2("UST app context handle %d created successfully for channel %s",
1324 ua_ctx->handle, ua_chan->name);
55cc08a6
DG
1325
1326error:
840cb59c 1327 health_code_update();
55cc08a6
DG
1328 return ret;
1329}
1330
53a80697
MD
1331/*
1332 * Set the filter on the tracer.
1333 */
1334static
1335int set_ust_event_filter(struct ust_app_event *ua_event,
1336 struct ust_app *app)
1337{
1338 int ret;
51755dc8 1339 struct lttng_ust_filter_bytecode *ust_bytecode = NULL;
53a80697 1340
840cb59c 1341 health_code_update();
86acf0da 1342
53a80697 1343 if (!ua_event->filter) {
86acf0da
DG
1344 ret = 0;
1345 goto error;
53a80697
MD
1346 }
1347
51755dc8
JG
1348 ust_bytecode = create_ust_bytecode_from_bytecode(ua_event->filter);
1349 if (!ust_bytecode) {
1350 ret = -LTTNG_ERR_NOMEM;
1351 goto error;
1352 }
fb45065e 1353 pthread_mutex_lock(&app->sock_lock);
51755dc8 1354 ret = ustctl_set_filter(app->sock, ust_bytecode,
53a80697 1355 ua_event->obj);
fb45065e 1356 pthread_mutex_unlock(&app->sock_lock);
53a80697 1357 if (ret < 0) {
ffe60014
DG
1358 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1359 ERR("UST app event %s filter failed for app (pid: %d) "
1360 "with ret %d", ua_event->attr.name, app->pid, ret);
1361 } else {
3757b385
DG
1362 /*
1363 * This is normal behavior, an application can die during the
1364 * creation process. Don't report an error so the execution can
1365 * continue normally.
1366 */
1367 ret = 0;
ffe60014
DG
1368 DBG3("UST app filter event failed. Application is dead.");
1369 }
53a80697
MD
1370 goto error;
1371 }
1372
1373 DBG2("UST filter set successfully for event %s", ua_event->name);
1374
1375error:
840cb59c 1376 health_code_update();
51755dc8 1377 free(ust_bytecode);
53a80697
MD
1378 return ret;
1379}
1380
51755dc8
JG
1381static
1382struct lttng_ust_event_exclusion *create_ust_exclusion_from_exclusion(
1383 struct lttng_event_exclusion *exclusion)
1384{
1385 struct lttng_ust_event_exclusion *ust_exclusion = NULL;
1386 size_t exclusion_alloc_size = sizeof(struct lttng_ust_event_exclusion) +
1387 LTTNG_UST_SYM_NAME_LEN * exclusion->count;
1388
1389 ust_exclusion = zmalloc(exclusion_alloc_size);
1390 if (!ust_exclusion) {
1391 PERROR("malloc");
1392 goto end;
1393 }
1394
1395 assert(sizeof(struct lttng_event_exclusion) ==
1396 sizeof(struct lttng_ust_event_exclusion));
1397 memcpy(ust_exclusion, exclusion, exclusion_alloc_size);
1398end:
1399 return ust_exclusion;
1400}
1401
7cc9a73c
JI
1402/*
1403 * Set event exclusions on the tracer.
1404 */
1405static
1406int set_ust_event_exclusion(struct ust_app_event *ua_event,
1407 struct ust_app *app)
1408{
1409 int ret;
51755dc8 1410 struct lttng_ust_event_exclusion *ust_exclusion = NULL;
7cc9a73c
JI
1411
1412 health_code_update();
1413
1414 if (!ua_event->exclusion || !ua_event->exclusion->count) {
1415 ret = 0;
1416 goto error;
1417 }
1418
51755dc8
JG
1419 ust_exclusion = create_ust_exclusion_from_exclusion(
1420 ua_event->exclusion);
1421 if (!ust_exclusion) {
1422 ret = -LTTNG_ERR_NOMEM;
1423 goto error;
1424 }
fb45065e 1425 pthread_mutex_lock(&app->sock_lock);
51755dc8 1426 ret = ustctl_set_exclusion(app->sock, ust_exclusion, ua_event->obj);
fb45065e 1427 pthread_mutex_unlock(&app->sock_lock);
7cc9a73c
JI
1428 if (ret < 0) {
1429 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1430 ERR("UST app event %s exclusions failed for app (pid: %d) "
1431 "with ret %d", ua_event->attr.name, app->pid, ret);
1432 } else {
1433 /*
1434 * This is normal behavior, an application can die during the
1435 * creation process. Don't report an error so the execution can
1436 * continue normally.
1437 */
1438 ret = 0;
1439 DBG3("UST app event exclusion failed. Application is dead.");
1440 }
1441 goto error;
1442 }
1443
1444 DBG2("UST exclusion set successfully for event %s", ua_event->name);
1445
1446error:
1447 health_code_update();
51755dc8 1448 free(ust_exclusion);
7cc9a73c
JI
1449 return ret;
1450}
1451
9730260e
DG
1452/*
1453 * Disable the specified event on to UST tracer for the UST session.
1454 */
1455static int disable_ust_event(struct ust_app *app,
1456 struct ust_app_session *ua_sess, struct ust_app_event *ua_event)
1457{
1458 int ret;
1459
840cb59c 1460 health_code_update();
86acf0da 1461
fb45065e 1462 pthread_mutex_lock(&app->sock_lock);
852d0037 1463 ret = ustctl_disable(app->sock, ua_event->obj);
fb45065e 1464 pthread_mutex_unlock(&app->sock_lock);
9730260e 1465 if (ret < 0) {
ffe60014
DG
1466 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1467 ERR("UST app event %s disable failed for app (pid: %d) "
1468 "and session handle %d with ret %d",
1469 ua_event->attr.name, app->pid, ua_sess->handle, ret);
1470 } else {
3757b385
DG
1471 /*
1472 * This is normal behavior, an application can die during the
1473 * creation process. Don't report an error so the execution can
1474 * continue normally.
1475 */
1476 ret = 0;
ffe60014
DG
1477 DBG3("UST app disable event failed. Application is dead.");
1478 }
9730260e
DG
1479 goto error;
1480 }
1481
1482 DBG2("UST app event %s disabled successfully for app (pid: %d)",
852d0037 1483 ua_event->attr.name, app->pid);
9730260e
DG
1484
1485error:
840cb59c 1486 health_code_update();
9730260e
DG
1487 return ret;
1488}
1489
78f0bacd
DG
1490/*
1491 * Disable the specified channel on to UST tracer for the UST session.
1492 */
1493static int disable_ust_channel(struct ust_app *app,
1494 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
1495{
1496 int ret;
1497
840cb59c 1498 health_code_update();
86acf0da 1499
fb45065e 1500 pthread_mutex_lock(&app->sock_lock);
852d0037 1501 ret = ustctl_disable(app->sock, ua_chan->obj);
fb45065e 1502 pthread_mutex_unlock(&app->sock_lock);
78f0bacd 1503 if (ret < 0) {
ffe60014
DG
1504 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1505 ERR("UST app channel %s disable failed for app (pid: %d) "
1506 "and session handle %d with ret %d",
1507 ua_chan->name, app->pid, ua_sess->handle, ret);
1508 } else {
3757b385
DG
1509 /*
1510 * This is normal behavior, an application can die during the
1511 * creation process. Don't report an error so the execution can
1512 * continue normally.
1513 */
1514 ret = 0;
ffe60014
DG
1515 DBG3("UST app disable channel failed. Application is dead.");
1516 }
78f0bacd
DG
1517 goto error;
1518 }
1519
78f0bacd 1520 DBG2("UST app channel %s disabled successfully for app (pid: %d)",
852d0037 1521 ua_chan->name, app->pid);
78f0bacd
DG
1522
1523error:
840cb59c 1524 health_code_update();
78f0bacd
DG
1525 return ret;
1526}
1527
1528/*
1529 * Enable the specified channel on to UST tracer for the UST session.
1530 */
1531static int enable_ust_channel(struct ust_app *app,
1532 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
1533{
1534 int ret;
1535
840cb59c 1536 health_code_update();
86acf0da 1537
fb45065e 1538 pthread_mutex_lock(&app->sock_lock);
852d0037 1539 ret = ustctl_enable(app->sock, ua_chan->obj);
fb45065e 1540 pthread_mutex_unlock(&app->sock_lock);
78f0bacd 1541 if (ret < 0) {
ffe60014
DG
1542 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1543 ERR("UST app channel %s enable failed for app (pid: %d) "
1544 "and session handle %d with ret %d",
1545 ua_chan->name, app->pid, ua_sess->handle, ret);
1546 } else {
3757b385
DG
1547 /*
1548 * This is normal behavior, an application can die during the
1549 * creation process. Don't report an error so the execution can
1550 * continue normally.
1551 */
1552 ret = 0;
ffe60014
DG
1553 DBG3("UST app enable channel failed. Application is dead.");
1554 }
78f0bacd
DG
1555 goto error;
1556 }
1557
1558 ua_chan->enabled = 1;
1559
1560 DBG2("UST app channel %s enabled successfully for app (pid: %d)",
852d0037 1561 ua_chan->name, app->pid);
78f0bacd
DG
1562
1563error:
840cb59c 1564 health_code_update();
78f0bacd
DG
1565 return ret;
1566}
1567
edb67388
DG
1568/*
1569 * Enable the specified event on to UST tracer for the UST session.
1570 */
1571static int enable_ust_event(struct ust_app *app,
1572 struct ust_app_session *ua_sess, struct ust_app_event *ua_event)
1573{
1574 int ret;
1575
840cb59c 1576 health_code_update();
86acf0da 1577
fb45065e 1578 pthread_mutex_lock(&app->sock_lock);
852d0037 1579 ret = ustctl_enable(app->sock, ua_event->obj);
fb45065e 1580 pthread_mutex_unlock(&app->sock_lock);
edb67388 1581 if (ret < 0) {
ffe60014
DG
1582 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1583 ERR("UST app event %s enable failed for app (pid: %d) "
1584 "and session handle %d with ret %d",
1585 ua_event->attr.name, app->pid, ua_sess->handle, ret);
1586 } else {
3757b385
DG
1587 /*
1588 * This is normal behavior, an application can die during the
1589 * creation process. Don't report an error so the execution can
1590 * continue normally.
1591 */
1592 ret = 0;
ffe60014
DG
1593 DBG3("UST app enable event failed. Application is dead.");
1594 }
edb67388
DG
1595 goto error;
1596 }
1597
1598 DBG2("UST app event %s enabled successfully for app (pid: %d)",
852d0037 1599 ua_event->attr.name, app->pid);
edb67388
DG
1600
1601error:
840cb59c 1602 health_code_update();
edb67388
DG
1603 return ret;
1604}
1605
099e26bd 1606/*
7972aab2 1607 * Send channel and stream buffer to application.
4f3ab6ee 1608 *
ffe60014 1609 * Return 0 on success. On error, a negative value is returned.
4f3ab6ee 1610 */
7972aab2
DG
1611static int send_channel_pid_to_ust(struct ust_app *app,
1612 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
4f3ab6ee
DG
1613{
1614 int ret;
ffe60014 1615 struct ust_app_stream *stream, *stmp;
4f3ab6ee
DG
1616
1617 assert(app);
ffe60014 1618 assert(ua_sess);
4f3ab6ee 1619 assert(ua_chan);
4f3ab6ee 1620
840cb59c 1621 health_code_update();
4f3ab6ee 1622
7972aab2
DG
1623 DBG("UST app sending channel %s to UST app sock %d", ua_chan->name,
1624 app->sock);
86acf0da 1625
ffe60014
DG
1626 /* Send channel to the application. */
1627 ret = ust_consumer_send_channel_to_ust(app, ua_sess, ua_chan);
a7169585
MD
1628 if (ret == -EPIPE || ret == -LTTNG_UST_ERR_EXITING) {
1629 ret = -ENOTCONN; /* Caused by app exiting. */
1630 goto error;
1631 } else if (ret < 0) {
b551a063
DG
1632 goto error;
1633 }
1634
d88aee68
DG
1635 health_code_update();
1636
ffe60014
DG
1637 /* Send all streams to application. */
1638 cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
1639 ret = ust_consumer_send_stream_to_ust(app, ua_chan, stream);
a7169585
MD
1640 if (ret == -EPIPE || ret == -LTTNG_UST_ERR_EXITING) {
1641 ret = -ENOTCONN; /* Caused by app exiting. */
1642 goto error;
1643 } else if (ret < 0) {
ffe60014
DG
1644 goto error;
1645 }
1646 /* We don't need the stream anymore once sent to the tracer. */
1647 cds_list_del(&stream->list);
fb45065e 1648 delete_ust_app_stream(-1, stream, app);
ffe60014 1649 }
ffe60014
DG
1650 /* Flag the channel that it is sent to the application. */
1651 ua_chan->is_sent = 1;
ffe60014 1652
b551a063 1653error:
840cb59c 1654 health_code_update();
b551a063
DG
1655 return ret;
1656}
1657
91d76f53 1658/*
5b4a0ec0 1659 * Create the specified event onto the UST tracer for a UST session.
d0b96690
DG
1660 *
1661 * Should be called with session mutex held.
91d76f53 1662 */
edb67388
DG
1663static
1664int create_ust_event(struct ust_app *app, struct ust_app_session *ua_sess,
1665 struct ust_app_channel *ua_chan, struct ust_app_event *ua_event)
91d76f53 1666{
5b4a0ec0 1667 int ret = 0;
284d8f55 1668
840cb59c 1669 health_code_update();
86acf0da 1670
5b4a0ec0 1671 /* Create UST event on tracer */
fb45065e 1672 pthread_mutex_lock(&app->sock_lock);
852d0037 1673 ret = ustctl_create_event(app->sock, &ua_event->attr, ua_chan->obj,
5b4a0ec0 1674 &ua_event->obj);
fb45065e 1675 pthread_mutex_unlock(&app->sock_lock);
5b4a0ec0 1676 if (ret < 0) {
ffe60014
DG
1677 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1678 ERR("Error ustctl create event %s for app pid: %d with ret %d",
1679 ua_event->attr.name, app->pid, ret);
1680 } else {
3757b385
DG
1681 /*
1682 * This is normal behavior, an application can die during the
1683 * creation process. Don't report an error so the execution can
1684 * continue normally.
1685 */
1686 ret = 0;
ffe60014
DG
1687 DBG3("UST app create event failed. Application is dead.");
1688 }
5b4a0ec0 1689 goto error;
91d76f53 1690 }
f6a9efaa 1691
5b4a0ec0 1692 ua_event->handle = ua_event->obj->handle;
284d8f55 1693
5b4a0ec0 1694 DBG2("UST app event %s created successfully for pid:%d",
852d0037 1695 ua_event->attr.name, app->pid);
f6a9efaa 1696
840cb59c 1697 health_code_update();
86acf0da 1698
025faf73
DG
1699 /* Set filter if one is present. */
1700 if (ua_event->filter) {
1701 ret = set_ust_event_filter(ua_event, app);
1702 if (ret < 0) {
1703 goto error;
1704 }
1705 }
1706
7cc9a73c
JI
1707 /* Set exclusions for the event */
1708 if (ua_event->exclusion) {
1709 ret = set_ust_event_exclusion(ua_event, app);
1710 if (ret < 0) {
1711 goto error;
1712 }
1713 }
1714
8535a6d9 1715 /* If event not enabled, disable it on the tracer */
40113787
MD
1716 if (ua_event->enabled) {
1717 /*
1718 * We now need to explicitly enable the event, since it
1719 * is now disabled at creation.
1720 */
1721 ret = enable_ust_event(app, ua_sess, ua_event);
1722 if (ret < 0) {
1723 /*
1724 * If we hit an EPERM, something is wrong with our enable call. If
1725 * we get an EEXIST, there is a problem on the tracer side since we
1726 * just created it.
1727 */
1728 switch (ret) {
1729 case -LTTNG_UST_ERR_PERM:
1730 /* Code flow problem */
1731 assert(0);
1732 case -LTTNG_UST_ERR_EXIST:
1733 /* It's OK for our use case. */
1734 ret = 0;
1735 break;
1736 default:
1737 break;
1738 }
1739 goto error;
1740 }
8535a6d9
DG
1741 }
1742
5b4a0ec0 1743error:
840cb59c 1744 health_code_update();
5b4a0ec0 1745 return ret;
91d76f53 1746}
48842b30 1747
5b4a0ec0
DG
1748/*
1749 * Copy data between an UST app event and a LTT event.
1750 */
421cb601 1751static void shadow_copy_event(struct ust_app_event *ua_event,
48842b30
DG
1752 struct ltt_ust_event *uevent)
1753{
b4ffad32
JI
1754 size_t exclusion_alloc_size;
1755
48842b30
DG
1756 strncpy(ua_event->name, uevent->attr.name, sizeof(ua_event->name));
1757 ua_event->name[sizeof(ua_event->name) - 1] = '\0';
1758
fc34caaa
DG
1759 ua_event->enabled = uevent->enabled;
1760
5b4a0ec0
DG
1761 /* Copy event attributes */
1762 memcpy(&ua_event->attr, &uevent->attr, sizeof(ua_event->attr));
1763
53a80697
MD
1764 /* Copy filter bytecode */
1765 if (uevent->filter) {
51755dc8 1766 ua_event->filter = copy_filter_bytecode(uevent->filter);
025faf73 1767 /* Filter might be NULL here in case of ENONEM. */
53a80697 1768 }
b4ffad32
JI
1769
1770 /* Copy exclusion data */
1771 if (uevent->exclusion) {
51755dc8 1772 exclusion_alloc_size = sizeof(struct lttng_event_exclusion) +
b4ffad32
JI
1773 LTTNG_UST_SYM_NAME_LEN * uevent->exclusion->count;
1774 ua_event->exclusion = zmalloc(exclusion_alloc_size);
5f8df26c
JI
1775 if (ua_event->exclusion == NULL) {
1776 PERROR("malloc");
1777 } else {
1778 memcpy(ua_event->exclusion, uevent->exclusion,
1779 exclusion_alloc_size);
b4ffad32
JI
1780 }
1781 }
48842b30
DG
1782}
1783
5b4a0ec0
DG
1784/*
1785 * Copy data between an UST app channel and a LTT channel.
1786 */
421cb601 1787static void shadow_copy_channel(struct ust_app_channel *ua_chan,
48842b30
DG
1788 struct ltt_ust_channel *uchan)
1789{
bec39940 1790 struct lttng_ht_iter iter;
48842b30 1791 struct ltt_ust_event *uevent;
55cc08a6 1792 struct ltt_ust_context *uctx;
48842b30
DG
1793 struct ust_app_event *ua_event;
1794
fc34caaa 1795 DBG2("UST app shadow copy of channel %s started", ua_chan->name);
48842b30
DG
1796
1797 strncpy(ua_chan->name, uchan->name, sizeof(ua_chan->name));
1798 ua_chan->name[sizeof(ua_chan->name) - 1] = '\0';
ffe60014 1799
1624d5b7
JD
1800 ua_chan->tracefile_size = uchan->tracefile_size;
1801 ua_chan->tracefile_count = uchan->tracefile_count;
1802
ffe60014
DG
1803 /* Copy event attributes since the layout is different. */
1804 ua_chan->attr.subbuf_size = uchan->attr.subbuf_size;
1805 ua_chan->attr.num_subbuf = uchan->attr.num_subbuf;
1806 ua_chan->attr.overwrite = uchan->attr.overwrite;
1807 ua_chan->attr.switch_timer_interval = uchan->attr.switch_timer_interval;
1808 ua_chan->attr.read_timer_interval = uchan->attr.read_timer_interval;
e9404c27 1809 ua_chan->monitor_timer_interval = uchan->monitor_timer_interval;
ffe60014 1810 ua_chan->attr.output = uchan->attr.output;
491d1539
MD
1811 ua_chan->attr.blocking_timeout = uchan->attr.u.s.blocking_timeout;
1812
ffe60014
DG
1813 /*
1814 * Note that the attribute channel type is not set since the channel on the
1815 * tracing registry side does not have this information.
1816 */
48842b30 1817
fc34caaa 1818 ua_chan->enabled = uchan->enabled;
7972aab2 1819 ua_chan->tracing_channel_id = uchan->id;
fc34caaa 1820
31746f93 1821 cds_list_for_each_entry(uctx, &uchan->ctx_list, list) {
bdf64013
JG
1822 struct ust_app_ctx *ua_ctx = alloc_ust_app_ctx(&uctx->ctx);
1823
55cc08a6
DG
1824 if (ua_ctx == NULL) {
1825 continue;
1826 }
bec39940
DG
1827 lttng_ht_node_init_ulong(&ua_ctx->node,
1828 (unsigned long) ua_ctx->ctx.ctx);
aa3514e9 1829 lttng_ht_add_ulong(ua_chan->ctx, &ua_ctx->node);
31746f93 1830 cds_list_add_tail(&ua_ctx->list, &ua_chan->ctx_list);
55cc08a6 1831 }
48842b30 1832
421cb601 1833 /* Copy all events from ltt ust channel to ust app channel */
bec39940 1834 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
18eace3b 1835 ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name,
39c5a3a7 1836 uevent->filter, uevent->attr.loglevel, uevent->exclusion);
18eace3b 1837 if (ua_event == NULL) {
421cb601 1838 DBG2("UST event %s not found on shadow copy channel",
48842b30 1839 uevent->attr.name);
284d8f55 1840 ua_event = alloc_ust_app_event(uevent->attr.name, &uevent->attr);
48842b30 1841 if (ua_event == NULL) {
5b4a0ec0 1842 continue;
48842b30 1843 }
421cb601 1844 shadow_copy_event(ua_event, uevent);
d0b96690 1845 add_unique_ust_app_event(ua_chan, ua_event);
48842b30 1846 }
48842b30
DG
1847 }
1848
fc34caaa 1849 DBG3("UST app shadow copy of channel %s done", ua_chan->name);
48842b30
DG
1850}
1851
5b4a0ec0
DG
1852/*
1853 * Copy data between a UST app session and a regular LTT session.
1854 */
421cb601 1855static void shadow_copy_session(struct ust_app_session *ua_sess,
bec39940 1856 struct ltt_ust_session *usess, struct ust_app *app)
48842b30 1857{
bec39940
DG
1858 struct lttng_ht_node_str *ua_chan_node;
1859 struct lttng_ht_iter iter;
48842b30
DG
1860 struct ltt_ust_channel *uchan;
1861 struct ust_app_channel *ua_chan;
477d7741
MD
1862 time_t rawtime;
1863 struct tm *timeinfo;
1864 char datetime[16];
1865 int ret;
d7ba1388 1866 char tmp_shm_path[PATH_MAX];
477d7741
MD
1867
1868 /* Get date and time for unique app path */
1869 time(&rawtime);
1870 timeinfo = localtime(&rawtime);
1871 strftime(datetime, sizeof(datetime), "%Y%m%d-%H%M%S", timeinfo);
48842b30 1872
421cb601 1873 DBG2("Shadow copy of session handle %d", ua_sess->handle);
48842b30 1874
7972aab2
DG
1875 ua_sess->tracing_id = usess->id;
1876 ua_sess->id = get_next_session_id();
1877 ua_sess->uid = app->uid;
1878 ua_sess->gid = app->gid;
1879 ua_sess->euid = usess->uid;
1880 ua_sess->egid = usess->gid;
1881 ua_sess->buffer_type = usess->buffer_type;
1882 ua_sess->bits_per_long = app->bits_per_long;
6addfa37 1883
7972aab2 1884 /* There is only one consumer object per session possible. */
6addfa37 1885 consumer_output_get(usess->consumer);
7972aab2 1886 ua_sess->consumer = usess->consumer;
6addfa37 1887
2bba9e53 1888 ua_sess->output_traces = usess->output_traces;
ecc48a90 1889 ua_sess->live_timer_interval = usess->live_timer_interval;
84ad93e8
DG
1890 copy_channel_attr_to_ustctl(&ua_sess->metadata_attr,
1891 &usess->metadata_attr);
7972aab2
DG
1892
1893 switch (ua_sess->buffer_type) {
1894 case LTTNG_BUFFER_PER_PID:
1895 ret = snprintf(ua_sess->path, sizeof(ua_sess->path),
dec56f6c 1896 DEFAULT_UST_TRACE_PID_PATH "/%s-%d-%s", app->name, app->pid,
7972aab2
DG
1897 datetime);
1898 break;
1899 case LTTNG_BUFFER_PER_UID:
1900 ret = snprintf(ua_sess->path, sizeof(ua_sess->path),
1901 DEFAULT_UST_TRACE_UID_PATH, ua_sess->uid, app->bits_per_long);
1902 break;
1903 default:
1904 assert(0);
1905 goto error;
1906 }
477d7741
MD
1907 if (ret < 0) {
1908 PERROR("asprintf UST shadow copy session");
477d7741 1909 assert(0);
7972aab2 1910 goto error;
477d7741
MD
1911 }
1912
3d071855
MD
1913 strncpy(ua_sess->root_shm_path, usess->root_shm_path,
1914 sizeof(ua_sess->root_shm_path));
1915 ua_sess->root_shm_path[sizeof(ua_sess->root_shm_path) - 1] = '\0';
d7ba1388
MD
1916 strncpy(ua_sess->shm_path, usess->shm_path,
1917 sizeof(ua_sess->shm_path));
1918 ua_sess->shm_path[sizeof(ua_sess->shm_path) - 1] = '\0';
1919 if (ua_sess->shm_path[0]) {
1920 switch (ua_sess->buffer_type) {
1921 case LTTNG_BUFFER_PER_PID:
1922 ret = snprintf(tmp_shm_path, sizeof(tmp_shm_path),
1923 DEFAULT_UST_TRACE_PID_PATH "/%s-%d-%s",
1924 app->name, app->pid, datetime);
1925 break;
1926 case LTTNG_BUFFER_PER_UID:
1927 ret = snprintf(tmp_shm_path, sizeof(tmp_shm_path),
1928 DEFAULT_UST_TRACE_UID_PATH,
1929 app->uid, app->bits_per_long);
1930 break;
1931 default:
1932 assert(0);
1933 goto error;
1934 }
1935 if (ret < 0) {
1936 PERROR("sprintf UST shadow copy session");
1937 assert(0);
1938 goto error;
1939 }
1940 strncat(ua_sess->shm_path, tmp_shm_path,
1941 sizeof(ua_sess->shm_path) - strlen(ua_sess->shm_path) - 1);
1942 ua_sess->shm_path[sizeof(ua_sess->shm_path) - 1] = '\0';
1943 }
1944
48842b30 1945 /* Iterate over all channels in global domain. */
bec39940
DG
1946 cds_lfht_for_each_entry(usess->domain_global.channels->ht, &iter.iter,
1947 uchan, node.node) {
1948 struct lttng_ht_iter uiter;
ba767faf 1949
bec39940
DG
1950 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
1951 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
5b4a0ec0 1952 if (ua_chan_node != NULL) {
fc34caaa 1953 /* Session exist. Contiuing. */
5b4a0ec0
DG
1954 continue;
1955 }
421cb601 1956
5b4a0ec0
DG
1957 DBG2("Channel %s not found on shadow session copy, creating it",
1958 uchan->name);
fb83fe64
JD
1959 ua_chan = alloc_ust_app_channel(uchan->name, ua_sess,
1960 &uchan->attr);
5b4a0ec0 1961 if (ua_chan == NULL) {
fc34caaa 1962 /* malloc failed FIXME: Might want to do handle ENOMEM .. */
5b4a0ec0 1963 continue;
48842b30 1964 }
5b4a0ec0 1965 shadow_copy_channel(ua_chan, uchan);
ffe60014
DG
1966 /*
1967 * The concept of metadata channel does not exist on the tracing
1968 * registry side of the session daemon so this can only be a per CPU
1969 * channel and not metadata.
1970 */
1971 ua_chan->attr.type = LTTNG_UST_CHAN_PER_CPU;
1972
bec39940 1973 lttng_ht_add_unique_str(ua_sess->channels, &ua_chan->node);
48842b30 1974 }
6addfa37 1975 return;
7972aab2
DG
1976
1977error:
6addfa37 1978 consumer_output_put(ua_sess->consumer);
48842b30
DG
1979}
1980
78f0bacd
DG
1981/*
1982 * Lookup sesison wrapper.
1983 */
84cd17c6
MD
1984static
1985void __lookup_session_by_app(struct ltt_ust_session *usess,
bec39940 1986 struct ust_app *app, struct lttng_ht_iter *iter)
84cd17c6
MD
1987{
1988 /* Get right UST app session from app */
d9bf3ca4 1989 lttng_ht_lookup(app->sessions, &usess->id, iter);
84cd17c6
MD
1990}
1991
421cb601
DG
1992/*
1993 * Return ust app session from the app session hashtable using the UST session
a991f516 1994 * id.
421cb601 1995 */
48842b30
DG
1996static struct ust_app_session *lookup_session_by_app(
1997 struct ltt_ust_session *usess, struct ust_app *app)
1998{
bec39940 1999 struct lttng_ht_iter iter;
d9bf3ca4 2000 struct lttng_ht_node_u64 *node;
48842b30 2001
84cd17c6 2002 __lookup_session_by_app(usess, app, &iter);
d9bf3ca4 2003 node = lttng_ht_iter_get_node_u64(&iter);
48842b30
DG
2004 if (node == NULL) {
2005 goto error;
2006 }
2007
2008 return caa_container_of(node, struct ust_app_session, node);
2009
2010error:
2011 return NULL;
2012}
2013
7972aab2
DG
2014/*
2015 * Setup buffer registry per PID for the given session and application. If none
2016 * is found, a new one is created, added to the global registry and
2017 * initialized. If regp is valid, it's set with the newly created object.
2018 *
2019 * Return 0 on success or else a negative value.
2020 */
2021static int setup_buffer_reg_pid(struct ust_app_session *ua_sess,
2022 struct ust_app *app, struct buffer_reg_pid **regp)
2023{
2024 int ret = 0;
2025 struct buffer_reg_pid *reg_pid;
2026
2027 assert(ua_sess);
2028 assert(app);
2029
2030 rcu_read_lock();
2031
2032 reg_pid = buffer_reg_pid_find(ua_sess->id);
2033 if (!reg_pid) {
2034 /*
2035 * This is the create channel path meaning that if there is NO
2036 * registry available, we have to create one for this session.
2037 */
d7ba1388 2038 ret = buffer_reg_pid_create(ua_sess->id, &reg_pid,
3d071855 2039 ua_sess->root_shm_path, ua_sess->shm_path);
7972aab2
DG
2040 if (ret < 0) {
2041 goto error;
2042 }
7972aab2
DG
2043 } else {
2044 goto end;
2045 }
2046
2047 /* Initialize registry. */
2048 ret = ust_registry_session_init(&reg_pid->registry->reg.ust, app,
2049 app->bits_per_long, app->uint8_t_alignment,
2050 app->uint16_t_alignment, app->uint32_t_alignment,
af6142cf
MD
2051 app->uint64_t_alignment, app->long_alignment,
2052 app->byte_order, app->version.major,
3d071855
MD
2053 app->version.minor, reg_pid->root_shm_path,
2054 reg_pid->shm_path,
d7ba1388 2055 ua_sess->euid, ua_sess->egid);
7972aab2 2056 if (ret < 0) {
286c991a
MD
2057 /*
2058 * reg_pid->registry->reg.ust is NULL upon error, so we need to
2059 * destroy the buffer registry, because it is always expected
2060 * that if the buffer registry can be found, its ust registry is
2061 * non-NULL.
2062 */
2063 buffer_reg_pid_destroy(reg_pid);
7972aab2
DG
2064 goto error;
2065 }
2066
286c991a
MD
2067 buffer_reg_pid_add(reg_pid);
2068
7972aab2
DG
2069 DBG3("UST app buffer registry per PID created successfully");
2070
2071end:
2072 if (regp) {
2073 *regp = reg_pid;
2074 }
2075error:
2076 rcu_read_unlock();
2077 return ret;
2078}
2079
2080/*
2081 * Setup buffer registry per UID for the given session and application. If none
2082 * is found, a new one is created, added to the global registry and
2083 * initialized. If regp is valid, it's set with the newly created object.
2084 *
2085 * Return 0 on success or else a negative value.
2086 */
2087static int setup_buffer_reg_uid(struct ltt_ust_session *usess,
d7ba1388 2088 struct ust_app_session *ua_sess,
7972aab2
DG
2089 struct ust_app *app, struct buffer_reg_uid **regp)
2090{
2091 int ret = 0;
2092 struct buffer_reg_uid *reg_uid;
2093
2094 assert(usess);
2095 assert(app);
2096
2097 rcu_read_lock();
2098
2099 reg_uid = buffer_reg_uid_find(usess->id, app->bits_per_long, app->uid);
2100 if (!reg_uid) {
2101 /*
2102 * This is the create channel path meaning that if there is NO
2103 * registry available, we have to create one for this session.
2104 */
2105 ret = buffer_reg_uid_create(usess->id, app->bits_per_long, app->uid,
3d071855
MD
2106 LTTNG_DOMAIN_UST, &reg_uid,
2107 ua_sess->root_shm_path, ua_sess->shm_path);
7972aab2
DG
2108 if (ret < 0) {
2109 goto error;
2110 }
7972aab2
DG
2111 } else {
2112 goto end;
2113 }
2114
2115 /* Initialize registry. */
af6142cf 2116 ret = ust_registry_session_init(&reg_uid->registry->reg.ust, NULL,
7972aab2
DG
2117 app->bits_per_long, app->uint8_t_alignment,
2118 app->uint16_t_alignment, app->uint32_t_alignment,
af6142cf
MD
2119 app->uint64_t_alignment, app->long_alignment,
2120 app->byte_order, app->version.major,
3d071855
MD
2121 app->version.minor, reg_uid->root_shm_path,
2122 reg_uid->shm_path, usess->uid, usess->gid);
7972aab2 2123 if (ret < 0) {
286c991a
MD
2124 /*
2125 * reg_uid->registry->reg.ust is NULL upon error, so we need to
2126 * destroy the buffer registry, because it is always expected
2127 * that if the buffer registry can be found, its ust registry is
2128 * non-NULL.
2129 */
2130 buffer_reg_uid_destroy(reg_uid, NULL);
7972aab2
DG
2131 goto error;
2132 }
2133 /* Add node to teardown list of the session. */
2134 cds_list_add(&reg_uid->lnode, &usess->buffer_reg_uid_list);
2135
286c991a 2136 buffer_reg_uid_add(reg_uid);
7972aab2 2137
286c991a 2138 DBG3("UST app buffer registry per UID created successfully");
7972aab2
DG
2139end:
2140 if (regp) {
2141 *regp = reg_uid;
2142 }
2143error:
2144 rcu_read_unlock();
2145 return ret;
2146}
2147
421cb601 2148/*
3d8ca23b 2149 * Create a session on the tracer side for the given app.
421cb601 2150 *
3d8ca23b
DG
2151 * On success, ua_sess_ptr is populated with the session pointer or else left
2152 * untouched. If the session was created, is_created is set to 1. On error,
2153 * it's left untouched. Note that ua_sess_ptr is mandatory but is_created can
2154 * be NULL.
2155 *
2156 * Returns 0 on success or else a negative code which is either -ENOMEM or
2157 * -ENOTCONN which is the default code if the ustctl_create_session fails.
421cb601 2158 */
03f91eaa 2159static int find_or_create_ust_app_session(struct ltt_ust_session *usess,
3d8ca23b
DG
2160 struct ust_app *app, struct ust_app_session **ua_sess_ptr,
2161 int *is_created)
421cb601 2162{
3d8ca23b 2163 int ret, created = 0;
421cb601
DG
2164 struct ust_app_session *ua_sess;
2165
3d8ca23b
DG
2166 assert(usess);
2167 assert(app);
2168 assert(ua_sess_ptr);
2169
840cb59c 2170 health_code_update();
86acf0da 2171
421cb601
DG
2172 ua_sess = lookup_session_by_app(usess, app);
2173 if (ua_sess == NULL) {
d9bf3ca4 2174 DBG2("UST app pid: %d session id %" PRIu64 " not found, creating it",
852d0037 2175 app->pid, usess->id);
40bbd087 2176 ua_sess = alloc_ust_app_session();
421cb601
DG
2177 if (ua_sess == NULL) {
2178 /* Only malloc can failed so something is really wrong */
3d8ca23b
DG
2179 ret = -ENOMEM;
2180 goto error;
421cb601 2181 }
477d7741 2182 shadow_copy_session(ua_sess, usess, app);
3d8ca23b 2183 created = 1;
421cb601
DG
2184 }
2185
7972aab2
DG
2186 switch (usess->buffer_type) {
2187 case LTTNG_BUFFER_PER_PID:
2188 /* Init local registry. */
2189 ret = setup_buffer_reg_pid(ua_sess, app, NULL);
421cb601 2190 if (ret < 0) {
e64207cf 2191 delete_ust_app_session(-1, ua_sess, app);
7972aab2
DG
2192 goto error;
2193 }
2194 break;
2195 case LTTNG_BUFFER_PER_UID:
2196 /* Look for a global registry. If none exists, create one. */
d7ba1388 2197 ret = setup_buffer_reg_uid(usess, ua_sess, app, NULL);
7972aab2 2198 if (ret < 0) {
e64207cf 2199 delete_ust_app_session(-1, ua_sess, app);
7972aab2
DG
2200 goto error;
2201 }
2202 break;
2203 default:
2204 assert(0);
2205 ret = -EINVAL;
2206 goto error;
2207 }
2208
2209 health_code_update();
2210
2211 if (ua_sess->handle == -1) {
fb45065e 2212 pthread_mutex_lock(&app->sock_lock);
7972aab2 2213 ret = ustctl_create_session(app->sock);
fb45065e 2214 pthread_mutex_unlock(&app->sock_lock);
7972aab2
DG
2215 if (ret < 0) {
2216 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
2217 ERR("Creating session for app pid %d with ret %d",
ffe60014
DG
2218 app->pid, ret);
2219 } else {
2220 DBG("UST app creating session failed. Application is dead");
3757b385
DG
2221 /*
2222 * This is normal behavior, an application can die during the
2223 * creation process. Don't report an error so the execution can
2224 * continue normally. This will get flagged ENOTCONN and the
2225 * caller will handle it.
2226 */
2227 ret = 0;
ffe60014 2228 }
d0b96690 2229 delete_ust_app_session(-1, ua_sess, app);
3d8ca23b
DG
2230 if (ret != -ENOMEM) {
2231 /*
2232 * Tracer is probably gone or got an internal error so let's
2233 * behave like it will soon unregister or not usable.
2234 */
2235 ret = -ENOTCONN;
2236 }
2237 goto error;
421cb601
DG
2238 }
2239
7972aab2
DG
2240 ua_sess->handle = ret;
2241
2242 /* Add ust app session to app's HT */
d9bf3ca4
MD
2243 lttng_ht_node_init_u64(&ua_sess->node,
2244 ua_sess->tracing_id);
2245 lttng_ht_add_unique_u64(app->sessions, &ua_sess->node);
10b56aef
MD
2246 lttng_ht_node_init_ulong(&ua_sess->ust_objd_node, ua_sess->handle);
2247 lttng_ht_add_unique_ulong(app->ust_sessions_objd,
2248 &ua_sess->ust_objd_node);
7972aab2
DG
2249
2250 DBG2("UST app session created successfully with handle %d", ret);
2251 }
2252
2253 *ua_sess_ptr = ua_sess;
2254 if (is_created) {
2255 *is_created = created;
2256 }
2257
2258 /* Everything went well. */
2259 ret = 0;
2260
2261error:
2262 health_code_update();
2263 return ret;
2264}
2265
6a6b2068
JG
2266/*
2267 * Match function for a hash table lookup of ust_app_ctx.
2268 *
2269 * It matches an ust app context based on the context type and, in the case
2270 * of perf counters, their name.
2271 */
2272static int ht_match_ust_app_ctx(struct cds_lfht_node *node, const void *_key)
2273{
2274 struct ust_app_ctx *ctx;
bdf64013 2275 const struct lttng_ust_context_attr *key;
6a6b2068
JG
2276
2277 assert(node);
2278 assert(_key);
2279
2280 ctx = caa_container_of(node, struct ust_app_ctx, node.node);
2281 key = _key;
2282
2283 /* Context type */
2284 if (ctx->ctx.ctx != key->ctx) {
2285 goto no_match;
2286 }
2287
bdf64013
JG
2288 switch(key->ctx) {
2289 case LTTNG_UST_CONTEXT_PERF_THREAD_COUNTER:
6a6b2068 2290 if (strncmp(key->u.perf_counter.name,
bdf64013
JG
2291 ctx->ctx.u.perf_counter.name,
2292 sizeof(key->u.perf_counter.name))) {
2293 goto no_match;
2294 }
2295 break;
2296 case LTTNG_UST_CONTEXT_APP_CONTEXT:
2297 if (strcmp(key->u.app_ctx.provider_name,
2298 ctx->ctx.u.app_ctx.provider_name) ||
2299 strcmp(key->u.app_ctx.ctx_name,
2300 ctx->ctx.u.app_ctx.ctx_name)) {
6a6b2068
JG
2301 goto no_match;
2302 }
bdf64013
JG
2303 break;
2304 default:
2305 break;
6a6b2068
JG
2306 }
2307
2308 /* Match. */
2309 return 1;
2310
2311no_match:
2312 return 0;
2313}
2314
2315/*
2316 * Lookup for an ust app context from an lttng_ust_context.
2317 *
be184a0f 2318 * Must be called while holding RCU read side lock.
6a6b2068
JG
2319 * Return an ust_app_ctx object or NULL on error.
2320 */
2321static
2322struct ust_app_ctx *find_ust_app_context(struct lttng_ht *ht,
bdf64013 2323 struct lttng_ust_context_attr *uctx)
6a6b2068
JG
2324{
2325 struct lttng_ht_iter iter;
2326 struct lttng_ht_node_ulong *node;
2327 struct ust_app_ctx *app_ctx = NULL;
2328
2329 assert(uctx);
2330 assert(ht);
2331
2332 /* Lookup using the lttng_ust_context_type and a custom match fct. */
2333 cds_lfht_lookup(ht->ht, ht->hash_fct((void *) uctx->ctx, lttng_ht_seed),
2334 ht_match_ust_app_ctx, uctx, &iter.iter);
2335 node = lttng_ht_iter_get_node_ulong(&iter);
2336 if (!node) {
2337 goto end;
2338 }
2339
2340 app_ctx = caa_container_of(node, struct ust_app_ctx, node);
2341
2342end:
2343 return app_ctx;
2344}
2345
7972aab2
DG
2346/*
2347 * Create a context for the channel on the tracer.
2348 *
2349 * Called with UST app session lock held and a RCU read side lock.
2350 */
2351static
c9edf082 2352int create_ust_app_channel_context(struct ust_app_channel *ua_chan,
bdf64013 2353 struct lttng_ust_context_attr *uctx,
7972aab2
DG
2354 struct ust_app *app)
2355{
2356 int ret = 0;
7972aab2
DG
2357 struct ust_app_ctx *ua_ctx;
2358
2359 DBG2("UST app adding context to channel %s", ua_chan->name);
2360
6a6b2068
JG
2361 ua_ctx = find_ust_app_context(ua_chan->ctx, uctx);
2362 if (ua_ctx) {
7972aab2
DG
2363 ret = -EEXIST;
2364 goto error;
2365 }
2366
2367 ua_ctx = alloc_ust_app_ctx(uctx);
2368 if (ua_ctx == NULL) {
2369 /* malloc failed */
7682f304 2370 ret = -ENOMEM;
7972aab2
DG
2371 goto error;
2372 }
2373
2374 lttng_ht_node_init_ulong(&ua_ctx->node, (unsigned long) ua_ctx->ctx.ctx);
aa3514e9 2375 lttng_ht_add_ulong(ua_chan->ctx, &ua_ctx->node);
31746f93 2376 cds_list_add_tail(&ua_ctx->list, &ua_chan->ctx_list);
7972aab2
DG
2377
2378 ret = create_ust_channel_context(ua_chan, ua_ctx, app);
2379 if (ret < 0) {
2380 goto error;
2381 }
2382
2383error:
2384 return ret;
2385}
2386
2387/*
2388 * Enable on the tracer side a ust app event for the session and channel.
2389 *
2390 * Called with UST app session lock held.
2391 */
2392static
2393int enable_ust_app_event(struct ust_app_session *ua_sess,
2394 struct ust_app_event *ua_event, struct ust_app *app)
2395{
2396 int ret;
2397
2398 ret = enable_ust_event(app, ua_sess, ua_event);
2399 if (ret < 0) {
2400 goto error;
2401 }
2402
2403 ua_event->enabled = 1;
2404
2405error:
2406 return ret;
2407}
2408
2409/*
2410 * Disable on the tracer side a ust app event for the session and channel.
2411 */
2412static int disable_ust_app_event(struct ust_app_session *ua_sess,
2413 struct ust_app_event *ua_event, struct ust_app *app)
2414{
2415 int ret;
2416
2417 ret = disable_ust_event(app, ua_sess, ua_event);
2418 if (ret < 0) {
2419 goto error;
2420 }
2421
2422 ua_event->enabled = 0;
2423
2424error:
2425 return ret;
2426}
2427
2428/*
2429 * Lookup ust app channel for session and disable it on the tracer side.
2430 */
2431static
2432int disable_ust_app_channel(struct ust_app_session *ua_sess,
2433 struct ust_app_channel *ua_chan, struct ust_app *app)
2434{
2435 int ret;
2436
2437 ret = disable_ust_channel(app, ua_sess, ua_chan);
2438 if (ret < 0) {
2439 goto error;
2440 }
2441
2442 ua_chan->enabled = 0;
2443
2444error:
2445 return ret;
2446}
2447
2448/*
2449 * Lookup ust app channel for session and enable it on the tracer side. This
2450 * MUST be called with a RCU read side lock acquired.
2451 */
2452static int enable_ust_app_channel(struct ust_app_session *ua_sess,
2453 struct ltt_ust_channel *uchan, struct ust_app *app)
2454{
2455 int ret = 0;
2456 struct lttng_ht_iter iter;
2457 struct lttng_ht_node_str *ua_chan_node;
2458 struct ust_app_channel *ua_chan;
2459
2460 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
2461 ua_chan_node = lttng_ht_iter_get_node_str(&iter);
2462 if (ua_chan_node == NULL) {
d9bf3ca4 2463 DBG2("Unable to find channel %s in ust session id %" PRIu64,
7972aab2
DG
2464 uchan->name, ua_sess->tracing_id);
2465 goto error;
2466 }
2467
2468 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
2469
2470 ret = enable_ust_channel(app, ua_sess, ua_chan);
2471 if (ret < 0) {
2472 goto error;
2473 }
2474
2475error:
2476 return ret;
2477}
2478
2479/*
2480 * Ask the consumer to create a channel and get it if successful.
2481 *
fad1ed2f
JR
2482 * Called with UST app session lock held.
2483 *
7972aab2
DG
2484 * Return 0 on success or else a negative value.
2485 */
2486static int do_consumer_create_channel(struct ltt_ust_session *usess,
2487 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan,
e098433c
JG
2488 int bitness, struct ust_registry_session *registry,
2489 uint64_t trace_archive_id)
7972aab2
DG
2490{
2491 int ret;
2492 unsigned int nb_fd = 0;
2493 struct consumer_socket *socket;
2494
2495 assert(usess);
2496 assert(ua_sess);
2497 assert(ua_chan);
2498 assert(registry);
2499
2500 rcu_read_lock();
2501 health_code_update();
2502
2503 /* Get the right consumer socket for the application. */
2504 socket = consumer_find_socket_by_bitness(bitness, usess->consumer);
2505 if (!socket) {
2506 ret = -EINVAL;
2507 goto error;
2508 }
2509
2510 health_code_update();
2511
2512 /* Need one fd for the channel. */
2513 ret = lttng_fd_get(LTTNG_FD_APPS, 1);
2514 if (ret < 0) {
2515 ERR("Exhausted number of available FD upon create channel");
2516 goto error;
2517 }
2518
2519 /*
2520 * Ask consumer to create channel. The consumer will return the number of
2521 * stream we have to expect.
2522 */
2523 ret = ust_consumer_ask_channel(ua_sess, ua_chan, usess->consumer, socket,
e098433c 2524 registry, trace_archive_id);
7972aab2
DG
2525 if (ret < 0) {
2526 goto error_ask;
2527 }
2528
2529 /*
2530 * Compute the number of fd needed before receiving them. It must be 2 per
2531 * stream (2 being the default value here).
2532 */
2533 nb_fd = DEFAULT_UST_STREAM_FD_NUM * ua_chan->expected_stream_count;
2534
2535 /* Reserve the amount of file descriptor we need. */
2536 ret = lttng_fd_get(LTTNG_FD_APPS, nb_fd);
2537 if (ret < 0) {
2538 ERR("Exhausted number of available FD upon create channel");
2539 goto error_fd_get_stream;
2540 }
2541
2542 health_code_update();
2543
2544 /*
2545 * Now get the channel from the consumer. This call wil populate the stream
2546 * list of that channel and set the ust objects.
2547 */
d9078d0c
DG
2548 if (usess->consumer->enabled) {
2549 ret = ust_consumer_get_channel(socket, ua_chan);
2550 if (ret < 0) {
2551 goto error_destroy;
2552 }
7972aab2
DG
2553 }
2554
2555 rcu_read_unlock();
2556 return 0;
2557
2558error_destroy:
2559 lttng_fd_put(LTTNG_FD_APPS, nb_fd);
2560error_fd_get_stream:
2561 /*
2562 * Initiate a destroy channel on the consumer since we had an error
2563 * handling it on our side. The return value is of no importance since we
2564 * already have a ret value set by the previous error that we need to
2565 * return.
2566 */
2567 (void) ust_consumer_destroy_channel(socket, ua_chan);
2568error_ask:
2569 lttng_fd_put(LTTNG_FD_APPS, 1);
2570error:
2571 health_code_update();
2572 rcu_read_unlock();
2573 return ret;
2574}
2575
2576/*
2577 * Duplicate the ust data object of the ust app stream and save it in the
2578 * buffer registry stream.
2579 *
2580 * Return 0 on success or else a negative value.
2581 */
2582static int duplicate_stream_object(struct buffer_reg_stream *reg_stream,
2583 struct ust_app_stream *stream)
2584{
2585 int ret;
2586
2587 assert(reg_stream);
2588 assert(stream);
2589
2590 /* Reserve the amount of file descriptor we need. */
2591 ret = lttng_fd_get(LTTNG_FD_APPS, 2);
2592 if (ret < 0) {
2593 ERR("Exhausted number of available FD upon duplicate stream");
2594 goto error;
2595 }
2596
2597 /* Duplicate object for stream once the original is in the registry. */
2598 ret = ustctl_duplicate_ust_object_data(&stream->obj,
2599 reg_stream->obj.ust);
2600 if (ret < 0) {
2601 ERR("Duplicate stream obj from %p to %p failed with ret %d",
2602 reg_stream->obj.ust, stream->obj, ret);
2603 lttng_fd_put(LTTNG_FD_APPS, 2);
2604 goto error;
2605 }
2606 stream->handle = stream->obj->handle;
2607
2608error:
2609 return ret;
2610}
2611
2612/*
2613 * Duplicate the ust data object of the ust app. channel and save it in the
2614 * buffer registry channel.
2615 *
2616 * Return 0 on success or else a negative value.
2617 */
2618static int duplicate_channel_object(struct buffer_reg_channel *reg_chan,
2619 struct ust_app_channel *ua_chan)
2620{
2621 int ret;
2622
2623 assert(reg_chan);
2624 assert(ua_chan);
2625
2626 /* Need two fds for the channel. */
2627 ret = lttng_fd_get(LTTNG_FD_APPS, 1);
2628 if (ret < 0) {
2629 ERR("Exhausted number of available FD upon duplicate channel");
2630 goto error_fd_get;
2631 }
2632
2633 /* Duplicate object for stream once the original is in the registry. */
2634 ret = ustctl_duplicate_ust_object_data(&ua_chan->obj, reg_chan->obj.ust);
2635 if (ret < 0) {
2636 ERR("Duplicate channel obj from %p to %p failed with ret: %d",
2637 reg_chan->obj.ust, ua_chan->obj, ret);
2638 goto error;
2639 }
2640 ua_chan->handle = ua_chan->obj->handle;
2641
2642 return 0;
2643
2644error:
2645 lttng_fd_put(LTTNG_FD_APPS, 1);
2646error_fd_get:
2647 return ret;
2648}
2649
2650/*
2651 * For a given channel buffer registry, setup all streams of the given ust
2652 * application channel.
2653 *
2654 * Return 0 on success or else a negative value.
2655 */
2656static int setup_buffer_reg_streams(struct buffer_reg_channel *reg_chan,
fb45065e
MD
2657 struct ust_app_channel *ua_chan,
2658 struct ust_app *app)
7972aab2
DG
2659{
2660 int ret = 0;
2661 struct ust_app_stream *stream, *stmp;
2662
2663 assert(reg_chan);
2664 assert(ua_chan);
2665
2666 DBG2("UST app setup buffer registry stream");
2667
2668 /* Send all streams to application. */
2669 cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
2670 struct buffer_reg_stream *reg_stream;
2671
2672 ret = buffer_reg_stream_create(&reg_stream);
2673 if (ret < 0) {
2674 goto error;
2675 }
2676
2677 /*
2678 * Keep original pointer and nullify it in the stream so the delete
2679 * stream call does not release the object.
2680 */
2681 reg_stream->obj.ust = stream->obj;
2682 stream->obj = NULL;
2683 buffer_reg_stream_add(reg_stream, reg_chan);
421cb601 2684
7972aab2
DG
2685 /* We don't need the streams anymore. */
2686 cds_list_del(&stream->list);
fb45065e 2687 delete_ust_app_stream(-1, stream, app);
7972aab2 2688 }
421cb601 2689
7972aab2
DG
2690error:
2691 return ret;
2692}
2693
2694/*
2695 * Create a buffer registry channel for the given session registry and
2696 * application channel object. If regp pointer is valid, it's set with the
2697 * created object. Important, the created object is NOT added to the session
2698 * registry hash table.
2699 *
2700 * Return 0 on success else a negative value.
2701 */
2702static int create_buffer_reg_channel(struct buffer_reg_session *reg_sess,
2703 struct ust_app_channel *ua_chan, struct buffer_reg_channel **regp)
2704{
2705 int ret;
2706 struct buffer_reg_channel *reg_chan = NULL;
2707
2708 assert(reg_sess);
2709 assert(ua_chan);
2710
2711 DBG2("UST app creating buffer registry channel for %s", ua_chan->name);
2712
2713 /* Create buffer registry channel. */
2714 ret = buffer_reg_channel_create(ua_chan->tracing_channel_id, &reg_chan);
2715 if (ret < 0) {
2716 goto error_create;
421cb601 2717 }
7972aab2
DG
2718 assert(reg_chan);
2719 reg_chan->consumer_key = ua_chan->key;
8c924c7b 2720 reg_chan->subbuf_size = ua_chan->attr.subbuf_size;
d07ceecd 2721 reg_chan->num_subbuf = ua_chan->attr.num_subbuf;
421cb601 2722
7972aab2
DG
2723 /* Create and add a channel registry to session. */
2724 ret = ust_registry_channel_add(reg_sess->reg.ust,
2725 ua_chan->tracing_channel_id);
2726 if (ret < 0) {
2727 goto error;
d88aee68 2728 }
7972aab2 2729 buffer_reg_channel_add(reg_sess, reg_chan);
d88aee68 2730
7972aab2
DG
2731 if (regp) {
2732 *regp = reg_chan;
3d8ca23b 2733 }
d88aee68 2734
7972aab2 2735 return 0;
3d8ca23b
DG
2736
2737error:
7972aab2
DG
2738 /* Safe because the registry channel object was not added to any HT. */
2739 buffer_reg_channel_destroy(reg_chan, LTTNG_DOMAIN_UST);
2740error_create:
3d8ca23b 2741 return ret;
421cb601
DG
2742}
2743
55cc08a6 2744/*
7972aab2
DG
2745 * Setup buffer registry channel for the given session registry and application
2746 * channel object. If regp pointer is valid, it's set with the created object.
d0b96690 2747 *
7972aab2 2748 * Return 0 on success else a negative value.
55cc08a6 2749 */
7972aab2 2750static int setup_buffer_reg_channel(struct buffer_reg_session *reg_sess,
fb45065e
MD
2751 struct ust_app_channel *ua_chan, struct buffer_reg_channel *reg_chan,
2752 struct ust_app *app)
55cc08a6 2753{
7972aab2 2754 int ret;
55cc08a6 2755
7972aab2
DG
2756 assert(reg_sess);
2757 assert(reg_chan);
2758 assert(ua_chan);
2759 assert(ua_chan->obj);
55cc08a6 2760
7972aab2 2761 DBG2("UST app setup buffer registry channel for %s", ua_chan->name);
55cc08a6 2762
7972aab2 2763 /* Setup all streams for the registry. */
fb45065e 2764 ret = setup_buffer_reg_streams(reg_chan, ua_chan, app);
7972aab2 2765 if (ret < 0) {
55cc08a6
DG
2766 goto error;
2767 }
2768
7972aab2
DG
2769 reg_chan->obj.ust = ua_chan->obj;
2770 ua_chan->obj = NULL;
55cc08a6 2771
7972aab2 2772 return 0;
55cc08a6
DG
2773
2774error:
7972aab2
DG
2775 buffer_reg_channel_remove(reg_sess, reg_chan);
2776 buffer_reg_channel_destroy(reg_chan, LTTNG_DOMAIN_UST);
55cc08a6
DG
2777 return ret;
2778}
2779
edb67388 2780/*
7972aab2 2781 * Send buffer registry channel to the application.
d0b96690 2782 *
7972aab2 2783 * Return 0 on success else a negative value.
edb67388 2784 */
7972aab2
DG
2785static int send_channel_uid_to_ust(struct buffer_reg_channel *reg_chan,
2786 struct ust_app *app, struct ust_app_session *ua_sess,
2787 struct ust_app_channel *ua_chan)
edb67388
DG
2788{
2789 int ret;
7972aab2 2790 struct buffer_reg_stream *reg_stream;
edb67388 2791
7972aab2
DG
2792 assert(reg_chan);
2793 assert(app);
2794 assert(ua_sess);
2795 assert(ua_chan);
2796
2797 DBG("UST app sending buffer registry channel to ust sock %d", app->sock);
2798
2799 ret = duplicate_channel_object(reg_chan, ua_chan);
edb67388
DG
2800 if (ret < 0) {
2801 goto error;
2802 }
2803
7972aab2
DG
2804 /* Send channel to the application. */
2805 ret = ust_consumer_send_channel_to_ust(app, ua_sess, ua_chan);
a7169585
MD
2806 if (ret == -EPIPE || ret == -LTTNG_UST_ERR_EXITING) {
2807 ret = -ENOTCONN; /* Caused by app exiting. */
2808 goto error;
2809 } else if (ret < 0) {
7972aab2
DG
2810 goto error;
2811 }
2812
2813 health_code_update();
2814
2815 /* Send all streams to application. */
2816 pthread_mutex_lock(&reg_chan->stream_list_lock);
2817 cds_list_for_each_entry(reg_stream, &reg_chan->streams, lnode) {
2818 struct ust_app_stream stream;
2819
2820 ret = duplicate_stream_object(reg_stream, &stream);
2821 if (ret < 0) {
2822 goto error_stream_unlock;
2823 }
2824
2825 ret = ust_consumer_send_stream_to_ust(app, ua_chan, &stream);
2826 if (ret < 0) {
fb45065e 2827 (void) release_ust_app_stream(-1, &stream, app);
a7169585
MD
2828 if (ret == -EPIPE || ret == -LTTNG_UST_ERR_EXITING) {
2829 ret = -ENOTCONN; /* Caused by app exiting. */
a7169585 2830 }
7972aab2
DG
2831 goto error_stream_unlock;
2832 }
edb67388 2833
7972aab2
DG
2834 /*
2835 * The return value is not important here. This function will output an
2836 * error if needed.
2837 */
fb45065e 2838 (void) release_ust_app_stream(-1, &stream, app);
7972aab2
DG
2839 }
2840 ua_chan->is_sent = 1;
2841
2842error_stream_unlock:
2843 pthread_mutex_unlock(&reg_chan->stream_list_lock);
edb67388
DG
2844error:
2845 return ret;
2846}
2847
9730260e 2848/*
7972aab2
DG
2849 * Create and send to the application the created buffers with per UID buffers.
2850 *
9acdc1d6 2851 * This MUST be called with a RCU read side lock acquired.
71e0a100 2852 * The session list lock and the session's lock must be acquired.
9acdc1d6 2853 *
7972aab2 2854 * Return 0 on success else a negative value.
9730260e 2855 */
7972aab2
DG
2856static int create_channel_per_uid(struct ust_app *app,
2857 struct ltt_ust_session *usess, struct ust_app_session *ua_sess,
2858 struct ust_app_channel *ua_chan)
9730260e
DG
2859{
2860 int ret;
7972aab2
DG
2861 struct buffer_reg_uid *reg_uid;
2862 struct buffer_reg_channel *reg_chan;
e098433c
JG
2863 struct ltt_session *session;
2864 enum lttng_error_code notification_ret;
2865 struct ust_registry_channel *chan_reg;
9730260e 2866
7972aab2
DG
2867 assert(app);
2868 assert(usess);
2869 assert(ua_sess);
2870 assert(ua_chan);
2871
2872 DBG("UST app creating channel %s with per UID buffers", ua_chan->name);
2873
2874 reg_uid = buffer_reg_uid_find(usess->id, app->bits_per_long, app->uid);
2875 /*
2876 * The session creation handles the creation of this global registry
2877 * object. If none can be find, there is a code flow problem or a
2878 * teardown race.
2879 */
2880 assert(reg_uid);
2881
2882 reg_chan = buffer_reg_channel_find(ua_chan->tracing_channel_id,
2883 reg_uid);
2721f7ea
JG
2884 if (reg_chan) {
2885 goto send_channel;
2886 }
7972aab2 2887
2721f7ea
JG
2888 /* Create the buffer registry channel object. */
2889 ret = create_buffer_reg_channel(reg_uid->registry, ua_chan, &reg_chan);
2890 if (ret < 0) {
2891 ERR("Error creating the UST channel \"%s\" registry instance",
f14256d6 2892 ua_chan->name);
2721f7ea
JG
2893 goto error;
2894 }
f14256d6 2895
e098433c
JG
2896 session = session_find_by_id(ua_sess->tracing_id);
2897 assert(session);
2898 assert(pthread_mutex_trylock(&session->lock));
2899 assert(session_trylock_list());
2900
2721f7ea
JG
2901 /*
2902 * Create the buffers on the consumer side. This call populates the
2903 * ust app channel object with all streams and data object.
2904 */
2905 ret = do_consumer_create_channel(usess, ua_sess, ua_chan,
e098433c
JG
2906 app->bits_per_long, reg_uid->registry->reg.ust,
2907 session->current_archive_id);
2721f7ea
JG
2908 if (ret < 0) {
2909 ERR("Error creating UST channel \"%s\" on the consumer daemon",
2910 ua_chan->name);
7972aab2
DG
2911
2912 /*
2721f7ea
JG
2913 * Let's remove the previously created buffer registry channel so
2914 * it's not visible anymore in the session registry.
7972aab2 2915 */
2721f7ea
JG
2916 ust_registry_channel_del_free(reg_uid->registry->reg.ust,
2917 ua_chan->tracing_channel_id, false);
2918 buffer_reg_channel_remove(reg_uid->registry, reg_chan);
2919 buffer_reg_channel_destroy(reg_chan, LTTNG_DOMAIN_UST);
2920 goto error;
7972aab2
DG
2921 }
2922
2721f7ea
JG
2923 /*
2924 * Setup the streams and add it to the session registry.
2925 */
2926 ret = setup_buffer_reg_channel(reg_uid->registry,
2927 ua_chan, reg_chan, app);
2928 if (ret < 0) {
2929 ERR("Error setting up UST channel \"%s\"", ua_chan->name);
2930 goto error;
2931 }
2932
e098433c
JG
2933 /* Notify the notification subsystem of the channel's creation. */
2934 pthread_mutex_lock(&reg_uid->registry->reg.ust->lock);
2935 chan_reg = ust_registry_channel_find(reg_uid->registry->reg.ust,
2936 ua_chan->tracing_channel_id);
2937 assert(chan_reg);
2938 chan_reg->consumer_key = ua_chan->key;
2939 chan_reg = NULL;
2940 pthread_mutex_unlock(&reg_uid->registry->reg.ust->lock);
e9404c27 2941
e098433c
JG
2942 notification_ret = notification_thread_command_add_channel(
2943 notification_thread_handle, session->name,
2944 ua_sess->euid, ua_sess->egid,
2945 ua_chan->name,
2946 ua_chan->key,
2947 LTTNG_DOMAIN_UST,
2948 ua_chan->attr.subbuf_size * ua_chan->attr.num_subbuf);
2949 if (notification_ret != LTTNG_OK) {
2950 ret = - (int) notification_ret;
2951 ERR("Failed to add channel to notification thread");
2952 goto error;
e9404c27
JG
2953 }
2954
2721f7ea 2955send_channel:
66ff8e3f
JG
2956 /* Send buffers to the application. */
2957 ret = send_channel_uid_to_ust(reg_chan, app, ua_sess, ua_chan);
2958 if (ret < 0) {
2959 if (ret != -ENOTCONN) {
2960 ERR("Error sending channel to application");
2961 }
2962 goto error;
2963 }
2964
9730260e
DG
2965error:
2966 return ret;
2967}
2968
78f0bacd 2969/*
7972aab2
DG
2970 * Create and send to the application the created buffers with per PID buffers.
2971 *
fad1ed2f 2972 * Called with UST app session lock held.
71e0a100 2973 * The session list lock and the session's lock must be acquired.
fad1ed2f 2974 *
7972aab2 2975 * Return 0 on success else a negative value.
78f0bacd 2976 */
7972aab2
DG
2977static int create_channel_per_pid(struct ust_app *app,
2978 struct ltt_ust_session *usess, struct ust_app_session *ua_sess,
2979 struct ust_app_channel *ua_chan)
78f0bacd 2980{
8535a6d9 2981 int ret;
7972aab2 2982 struct ust_registry_session *registry;
e9404c27
JG
2983 enum lttng_error_code cmd_ret;
2984 struct ltt_session *session;
2985 uint64_t chan_reg_key;
2986 struct ust_registry_channel *chan_reg;
78f0bacd 2987
7972aab2
DG
2988 assert(app);
2989 assert(usess);
2990 assert(ua_sess);
2991 assert(ua_chan);
2992
2993 DBG("UST app creating channel %s with per PID buffers", ua_chan->name);
2994
2995 rcu_read_lock();
2996
2997 registry = get_session_registry(ua_sess);
fad1ed2f 2998 /* The UST app session lock is held, registry shall not be null. */
7972aab2
DG
2999 assert(registry);
3000
3001 /* Create and add a new channel registry to session. */
3002 ret = ust_registry_channel_add(registry, ua_chan->key);
78f0bacd 3003 if (ret < 0) {
f14256d6
MD
3004 ERR("Error creating the UST channel \"%s\" registry instance",
3005 ua_chan->name);
78f0bacd
DG
3006 goto error;
3007 }
3008
e098433c
JG
3009 session = session_find_by_id(ua_sess->tracing_id);
3010 assert(session);
3011
3012 assert(pthread_mutex_trylock(&session->lock));
3013 assert(session_trylock_list());
3014
7972aab2
DG
3015 /* Create and get channel on the consumer side. */
3016 ret = do_consumer_create_channel(usess, ua_sess, ua_chan,
e098433c
JG
3017 app->bits_per_long, registry,
3018 session->current_archive_id);
7972aab2 3019 if (ret < 0) {
f14256d6
MD
3020 ERR("Error creating UST channel \"%s\" on the consumer daemon",
3021 ua_chan->name);
5b951542 3022 goto error_remove_from_registry;
7972aab2
DG
3023 }
3024
3025 ret = send_channel_pid_to_ust(app, ua_sess, ua_chan);
3026 if (ret < 0) {
a7169585
MD
3027 if (ret != -ENOTCONN) {
3028 ERR("Error sending channel to application");
3029 }
5b951542 3030 goto error_remove_from_registry;
7972aab2 3031 }
8535a6d9 3032
e9404c27
JG
3033 chan_reg_key = ua_chan->key;
3034 pthread_mutex_lock(&registry->lock);
3035 chan_reg = ust_registry_channel_find(registry, chan_reg_key);
3036 assert(chan_reg);
3037 chan_reg->consumer_key = ua_chan->key;
3038 pthread_mutex_unlock(&registry->lock);
3039
3040 cmd_ret = notification_thread_command_add_channel(
3041 notification_thread_handle, session->name,
3042 ua_sess->euid, ua_sess->egid,
3043 ua_chan->name,
3044 ua_chan->key,
3045 LTTNG_DOMAIN_UST,
3046 ua_chan->attr.subbuf_size * ua_chan->attr.num_subbuf);
3047 if (cmd_ret != LTTNG_OK) {
3048 ret = - (int) cmd_ret;
3049 ERR("Failed to add channel to notification thread");
5b951542 3050 goto error_remove_from_registry;
e9404c27
JG
3051 }
3052
5b951542
MD
3053error_remove_from_registry:
3054 if (ret) {
3055 ust_registry_channel_del_free(registry, ua_chan->key, false);
3056 }
78f0bacd 3057error:
7972aab2 3058 rcu_read_unlock();
78f0bacd
DG
3059 return ret;
3060}
3061
3062/*
7972aab2
DG
3063 * From an already allocated ust app channel, create the channel buffers if
3064 * need and send it to the application. This MUST be called with a RCU read
3065 * side lock acquired.
3066 *
fad1ed2f
JR
3067 * Called with UST app session lock held.
3068 *
a7169585
MD
3069 * Return 0 on success or else a negative value. Returns -ENOTCONN if
3070 * the application exited concurrently.
78f0bacd 3071 */
7972aab2
DG
3072static int do_create_channel(struct ust_app *app,
3073 struct ltt_ust_session *usess, struct ust_app_session *ua_sess,
3074 struct ust_app_channel *ua_chan)
78f0bacd 3075{
7972aab2 3076 int ret;
78f0bacd 3077
7972aab2
DG
3078 assert(app);
3079 assert(usess);
3080 assert(ua_sess);
3081 assert(ua_chan);
3082
3083 /* Handle buffer type before sending the channel to the application. */
3084 switch (usess->buffer_type) {
3085 case LTTNG_BUFFER_PER_UID:
3086 {
3087 ret = create_channel_per_uid(app, usess, ua_sess, ua_chan);
3088 if (ret < 0) {
3089 goto error;
3090 }
3091 break;
3092 }
3093 case LTTNG_BUFFER_PER_PID:
3094 {
3095 ret = create_channel_per_pid(app, usess, ua_sess, ua_chan);
3096 if (ret < 0) {
3097 goto error;
3098 }
3099 break;
3100 }
3101 default:
3102 assert(0);
3103 ret = -EINVAL;
78f0bacd
DG
3104 goto error;
3105 }
3106
7972aab2
DG
3107 /* Initialize ust objd object using the received handle and add it. */
3108 lttng_ht_node_init_ulong(&ua_chan->ust_objd_node, ua_chan->handle);
3109 lttng_ht_add_unique_ulong(app->ust_objd, &ua_chan->ust_objd_node);
78f0bacd 3110
7972aab2
DG
3111 /* If channel is not enabled, disable it on the tracer */
3112 if (!ua_chan->enabled) {
3113 ret = disable_ust_channel(app, ua_sess, ua_chan);
3114 if (ret < 0) {
3115 goto error;
3116 }
78f0bacd
DG
3117 }
3118
3119error:
3120 return ret;
3121}
3122
284d8f55 3123/*
4d710ac2
DG
3124 * Create UST app channel and create it on the tracer. Set ua_chanp of the
3125 * newly created channel if not NULL.
d0b96690 3126 *
36b588ed 3127 * Called with UST app session lock and RCU read-side lock held.
7972aab2 3128 *
a7169585
MD
3129 * Return 0 on success or else a negative value. Returns -ENOTCONN if
3130 * the application exited concurrently.
284d8f55 3131 */
4d710ac2
DG
3132static int create_ust_app_channel(struct ust_app_session *ua_sess,
3133 struct ltt_ust_channel *uchan, struct ust_app *app,
7972aab2 3134 enum lttng_ust_chan_type type, struct ltt_ust_session *usess,
4d710ac2 3135 struct ust_app_channel **ua_chanp)
5b4a0ec0
DG
3136{
3137 int ret = 0;
bec39940
DG
3138 struct lttng_ht_iter iter;
3139 struct lttng_ht_node_str *ua_chan_node;
5b4a0ec0
DG
3140 struct ust_app_channel *ua_chan;
3141
3142 /* Lookup channel in the ust app session */
bec39940
DG
3143 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
3144 ua_chan_node = lttng_ht_iter_get_node_str(&iter);
fc34caaa 3145 if (ua_chan_node != NULL) {
5b4a0ec0 3146 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
fc34caaa 3147 goto end;
5b4a0ec0
DG
3148 }
3149
d0b96690 3150 ua_chan = alloc_ust_app_channel(uchan->name, ua_sess, &uchan->attr);
fc34caaa
DG
3151 if (ua_chan == NULL) {
3152 /* Only malloc can fail here */
4d710ac2 3153 ret = -ENOMEM;
094d1690 3154 goto error_alloc;
fc34caaa
DG
3155 }
3156 shadow_copy_channel(ua_chan, uchan);
3157
ffe60014
DG
3158 /* Set channel type. */
3159 ua_chan->attr.type = type;
3160
7972aab2 3161 ret = do_create_channel(app, usess, ua_sess, ua_chan);
5b4a0ec0
DG
3162 if (ret < 0) {
3163 goto error;
3164 }
3165
fc34caaa 3166 DBG2("UST app create channel %s for PID %d completed", ua_chan->name,
852d0037 3167 app->pid);
fc34caaa 3168
d0b96690
DG
3169 /* Only add the channel if successful on the tracer side. */
3170 lttng_ht_add_unique_str(ua_sess->channels, &ua_chan->node);
fc34caaa 3171end:
4d710ac2
DG
3172 if (ua_chanp) {
3173 *ua_chanp = ua_chan;
3174 }
3175
3176 /* Everything went well. */
3177 return 0;
5b4a0ec0
DG
3178
3179error:
d0b96690 3180 delete_ust_app_channel(ua_chan->is_sent ? app->sock : -1, ua_chan, app);
094d1690 3181error_alloc:
4d710ac2 3182 return ret;
5b4a0ec0
DG
3183}
3184
3185/*
3186 * Create UST app event and create it on the tracer side.
d0b96690
DG
3187 *
3188 * Called with ust app session mutex held.
5b4a0ec0 3189 */
edb67388
DG
3190static
3191int create_ust_app_event(struct ust_app_session *ua_sess,
3192 struct ust_app_channel *ua_chan, struct ltt_ust_event *uevent,
3193 struct ust_app *app)
284d8f55 3194{
edb67388 3195 int ret = 0;
5b4a0ec0 3196 struct ust_app_event *ua_event;
284d8f55 3197
5b4a0ec0 3198 /* Get event node */
18eace3b 3199 ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name,
39c5a3a7 3200 uevent->filter, uevent->attr.loglevel, uevent->exclusion);
18eace3b 3201 if (ua_event != NULL) {
fc34caaa 3202 ret = -EEXIST;
edb67388
DG
3203 goto end;
3204 }
5b4a0ec0 3205
edb67388
DG
3206 /* Does not exist so create one */
3207 ua_event = alloc_ust_app_event(uevent->attr.name, &uevent->attr);
3208 if (ua_event == NULL) {
3209 /* Only malloc can failed so something is really wrong */
3210 ret = -ENOMEM;
fc34caaa 3211 goto end;
5b4a0ec0 3212 }
edb67388 3213 shadow_copy_event(ua_event, uevent);
5b4a0ec0 3214
edb67388 3215 /* Create it on the tracer side */
5b4a0ec0 3216 ret = create_ust_event(app, ua_sess, ua_chan, ua_event);
284d8f55 3217 if (ret < 0) {
fc34caaa 3218 /* Not found previously means that it does not exist on the tracer */
76f66f63 3219 assert(ret != -LTTNG_UST_ERR_EXIST);
284d8f55
DG
3220 goto error;
3221 }
3222
d0b96690 3223 add_unique_ust_app_event(ua_chan, ua_event);
284d8f55 3224
fc34caaa 3225 DBG2("UST app create event %s for PID %d completed", ua_event->name,
852d0037 3226 app->pid);
7f79d3a1 3227
edb67388 3228end:
fc34caaa
DG
3229 return ret;
3230
5b4a0ec0 3231error:
fc34caaa 3232 /* Valid. Calling here is already in a read side lock */