Fix: grab more than one packet for snapshots
[lttng-tools.git] / src / common / kernel-consumer / kernel-consumer.c
CommitLineData
3bd1e081
MD
1/*
2 * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
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.
3bd1e081
MD
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.
3bd1e081
MD
17 */
18
19#define _GNU_SOURCE
6c1c0768 20#define _LGPL_SOURCE
3bd1e081 21#include <assert.h>
3bd1e081
MD
22#include <poll.h>
23#include <pthread.h>
24#include <stdlib.h>
25#include <string.h>
26#include <sys/mman.h>
27#include <sys/socket.h>
28#include <sys/types.h>
77c7c900 29#include <inttypes.h>
3bd1e081 30#include <unistd.h>
dbb5dfe6 31#include <sys/stat.h>
3bd1e081 32
51a9e1c7 33#include <bin/lttng-consumerd/health-consumerd.h>
990570ed 34#include <common/common.h>
10a8a223 35#include <common/kernel-ctl/kernel-ctl.h>
10a8a223 36#include <common/sessiond-comm/sessiond-comm.h>
00e2e675 37#include <common/sessiond-comm/relayd.h>
dbb5dfe6 38#include <common/compat/fcntl.h>
f263b7fd 39#include <common/compat/endian.h>
acdb9057 40#include <common/pipe.h>
00e2e675 41#include <common/relayd/relayd.h>
fe4477ee 42#include <common/utils.h>
07b86b52 43#include <common/consumer-stream.h>
309167d2 44#include <common/index/index.h>
d3e2ba59 45#include <common/consumer-timer.h>
0857097f 46
10a8a223 47#include "kernel-consumer.h"
3bd1e081
MD
48
49extern struct lttng_consumer_global_data consumer_data;
50extern int consumer_poll_timeout;
51extern volatile int consumer_quit;
52
3bd1e081
MD
53/*
54 * Take a snapshot for a specific fd
55 *
56 * Returns 0 on success, < 0 on error
57 */
ffe60014 58int lttng_kconsumer_take_snapshot(struct lttng_consumer_stream *stream)
3bd1e081
MD
59{
60 int ret = 0;
61 int infd = stream->wait_fd;
62
63 ret = kernctl_snapshot(infd);
64 if (ret != 0) {
5a510c9f 65 PERROR("Getting sub-buffer snapshot.");
56591bac 66 ret = -errno;
3bd1e081
MD
67 }
68
69 return ret;
70}
71
72/*
73 * Get the produced position
74 *
75 * Returns 0 on success, < 0 on error
76 */
ffe60014 77int lttng_kconsumer_get_produced_snapshot(struct lttng_consumer_stream *stream,
3bd1e081
MD
78 unsigned long *pos)
79{
80 int ret;
81 int infd = stream->wait_fd;
82
83 ret = kernctl_snapshot_get_produced(infd, pos);
84 if (ret != 0) {
5a510c9f 85 PERROR("kernctl_snapshot_get_produced");
56591bac 86 ret = -errno;
3bd1e081
MD
87 }
88
89 return ret;
90}
91
07b86b52
JD
92/*
93 * Get the consumerd position
94 *
95 * Returns 0 on success, < 0 on error
96 */
97int lttng_kconsumer_get_consumed_snapshot(struct lttng_consumer_stream *stream,
98 unsigned long *pos)
99{
100 int ret;
101 int infd = stream->wait_fd;
102
103 ret = kernctl_snapshot_get_consumed(infd, pos);
104 if (ret != 0) {
5a510c9f 105 PERROR("kernctl_snapshot_get_consumed");
56591bac 106 ret = -errno;
07b86b52
JD
107 }
108
109 return ret;
110}
111
07b86b52
JD
112/*
113 * Take a snapshot of all the stream of a channel
114 *
115 * Returns 0 on success, < 0 on error
116 */
117int lttng_kconsumer_snapshot_channel(uint64_t key, char *path,
d07ceecd 118 uint64_t relayd_id, uint64_t nb_packets_per_stream,
5c786ded 119 struct lttng_consumer_local_data *ctx)
07b86b52
JD
120{
121 int ret;
122 unsigned long consumed_pos, produced_pos;
123 struct lttng_consumer_channel *channel;
124 struct lttng_consumer_stream *stream;
125
6a00837f 126 DBG("Kernel consumer snapshot channel %" PRIu64, key);
07b86b52
JD
127
128 rcu_read_lock();
129
130 channel = consumer_find_channel(key);
131 if (!channel) {
6a00837f 132 ERR("No channel found for key %" PRIu64, key);
07b86b52
JD
133 ret = -1;
134 goto end;
135 }
136
137 /* Splice is not supported yet for channel snapshot. */
138 if (channel->output != CONSUMER_CHANNEL_MMAP) {
139 ERR("Unsupported output %d", channel->output);
140 ret = -1;
141 goto end;
142 }
143
10a50311 144 cds_list_for_each_entry(stream, &channel->streams.head, send_node) {
9ce5646a
MD
145
146 health_code_update();
147
07b86b52
JD
148 /*
149 * Lock stream because we are about to change its state.
150 */
151 pthread_mutex_lock(&stream->lock);
152
29decac3
DG
153 /*
154 * Assign the received relayd ID so we can use it for streaming. The streams
155 * are not visible to anyone so this is OK to change it.
156 */
07b86b52
JD
157 stream->net_seq_idx = relayd_id;
158 channel->relayd_id = relayd_id;
159 if (relayd_id != (uint64_t) -1ULL) {
10a50311 160 ret = consumer_send_relayd_stream(stream, path);
07b86b52
JD
161 if (ret < 0) {
162 ERR("sending stream to relayd");
163 goto end_unlock;
164 }
07b86b52
JD
165 } else {
166 ret = utils_create_stream_file(path, stream->name,
10a50311
JD
167 stream->chan->tracefile_size,
168 stream->tracefile_count_current,
309167d2 169 stream->uid, stream->gid, NULL);
07b86b52
JD
170 if (ret < 0) {
171 ERR("utils_create_stream_file");
172 goto end_unlock;
173 }
174
175 stream->out_fd = ret;
176 stream->tracefile_size_current = 0;
177
81ea21bf
MD
178 DBG("Kernel consumer snapshot stream %s/%s (%" PRIu64 ")",
179 path, stream->name, stream->key);
07b86b52 180 }
601262d6
JD
181 if (relayd_id != -1ULL) {
182 ret = consumer_send_relayd_streams_sent(relayd_id);
183 if (ret < 0) {
184 ERR("sending streams sent to relayd");
185 goto end_unlock;
186 }
a4baae1b 187 }
07b86b52
JD
188
189 ret = kernctl_buffer_flush(stream->wait_fd);
190 if (ret < 0) {
10a50311 191 ERR("Failed to flush kernel stream");
56591bac 192 ret = -errno;
07b86b52
JD
193 goto end_unlock;
194 }
195
196 ret = lttng_kconsumer_take_snapshot(stream);
197 if (ret < 0) {
198 ERR("Taking kernel snapshot");
199 goto end_unlock;
200 }
201
202 ret = lttng_kconsumer_get_produced_snapshot(stream, &produced_pos);
203 if (ret < 0) {
204 ERR("Produced kernel snapshot position");
205 goto end_unlock;
206 }
207
208 ret = lttng_kconsumer_get_consumed_snapshot(stream, &consumed_pos);
209 if (ret < 0) {
210 ERR("Consumerd kernel snapshot position");
211 goto end_unlock;
212 }
213
214 if (stream->max_sb_size == 0) {
215 ret = kernctl_get_max_subbuf_size(stream->wait_fd,
216 &stream->max_sb_size);
217 if (ret < 0) {
218 ERR("Getting kernel max_sb_size");
56591bac 219 ret = -errno;
07b86b52
JD
220 goto end_unlock;
221 }
222 }
223
d07ceecd
MD
224 consumed_pos = consumer_get_consume_start_pos(consumed_pos,
225 produced_pos, nb_packets_per_stream,
226 stream->max_sb_size);
5c786ded 227
07b86b52
JD
228 while (consumed_pos < produced_pos) {
229 ssize_t read_len;
230 unsigned long len, padded_len;
231
9ce5646a
MD
232 health_code_update();
233
07b86b52
JD
234 DBG("Kernel consumer taking snapshot at pos %lu", consumed_pos);
235
236 ret = kernctl_get_subbuf(stream->wait_fd, &consumed_pos);
237 if (ret < 0) {
238 if (errno != EAGAIN) {
239 PERROR("kernctl_get_subbuf snapshot");
56591bac 240 ret = -errno;
07b86b52
JD
241 goto end_unlock;
242 }
243 DBG("Kernel consumer get subbuf failed. Skipping it.");
244 consumed_pos += stream->max_sb_size;
245 continue;
246 }
247
248 ret = kernctl_get_subbuf_size(stream->wait_fd, &len);
249 if (ret < 0) {
250 ERR("Snapshot kernctl_get_subbuf_size");
56591bac 251 ret = -errno;
29decac3 252 goto error_put_subbuf;
07b86b52
JD
253 }
254
255 ret = kernctl_get_padded_subbuf_size(stream->wait_fd, &padded_len);
256 if (ret < 0) {
257 ERR("Snapshot kernctl_get_padded_subbuf_size");
56591bac 258 ret = -errno;
29decac3 259 goto error_put_subbuf;
07b86b52
JD
260 }
261
262 read_len = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, len,
309167d2 263 padded_len - len, NULL);
07b86b52 264 /*
29decac3
DG
265 * We write the padded len in local tracefiles but the data len
266 * when using a relay. Display the error but continue processing
267 * to try to release the subbuffer.
07b86b52
JD
268 */
269 if (relayd_id != (uint64_t) -1ULL) {
270 if (read_len != len) {
271 ERR("Error sending to the relay (ret: %zd != len: %lu)",
272 read_len, len);
273 }
274 } else {
275 if (read_len != padded_len) {
276 ERR("Error writing to tracefile (ret: %zd != len: %lu)",
277 read_len, padded_len);
278 }
279 }
280
281 ret = kernctl_put_subbuf(stream->wait_fd);
282 if (ret < 0) {
283 ERR("Snapshot kernctl_put_subbuf");
56591bac 284 ret = -errno;
07b86b52
JD
285 goto end_unlock;
286 }
287 consumed_pos += stream->max_sb_size;
288 }
289
290 if (relayd_id == (uint64_t) -1ULL) {
fdf9986c
MD
291 if (stream->out_fd >= 0) {
292 ret = close(stream->out_fd);
293 if (ret < 0) {
294 PERROR("Kernel consumer snapshot close out_fd");
295 goto end_unlock;
296 }
297 stream->out_fd = -1;
07b86b52 298 }
07b86b52
JD
299 } else {
300 close_relayd_stream(stream);
301 stream->net_seq_idx = (uint64_t) -1ULL;
302 }
303 pthread_mutex_unlock(&stream->lock);
304 }
305
306 /* All good! */
307 ret = 0;
308 goto end;
309
29decac3
DG
310error_put_subbuf:
311 ret = kernctl_put_subbuf(stream->wait_fd);
312 if (ret < 0) {
56591bac 313 ret = -errno;
29decac3
DG
314 ERR("Snapshot kernctl_put_subbuf error path");
315 }
07b86b52
JD
316end_unlock:
317 pthread_mutex_unlock(&stream->lock);
318end:
319 rcu_read_unlock();
320 return ret;
321}
322
323/*
324 * Read the whole metadata available for a snapshot.
325 *
326 * Returns 0 on success, < 0 on error
327 */
328int lttng_kconsumer_snapshot_metadata(uint64_t key, char *path,
e2039c7a 329 uint64_t relayd_id, struct lttng_consumer_local_data *ctx)
07b86b52 330{
d771f832
DG
331 int ret, use_relayd = 0;
332 ssize_t ret_read;
07b86b52
JD
333 struct lttng_consumer_channel *metadata_channel;
334 struct lttng_consumer_stream *metadata_stream;
d771f832
DG
335
336 assert(ctx);
07b86b52
JD
337
338 DBG("Kernel consumer snapshot metadata with key %" PRIu64 " at path %s",
339 key, path);
340
341 rcu_read_lock();
342
343 metadata_channel = consumer_find_channel(key);
344 if (!metadata_channel) {
d771f832 345 ERR("Kernel snapshot metadata not found for key %" PRIu64, key);
07b86b52 346 ret = -1;
d771f832 347 goto error;
07b86b52
JD
348 }
349
350 metadata_stream = metadata_channel->metadata_stream;
351 assert(metadata_stream);
352
d771f832 353 /* Flag once that we have a valid relayd for the stream. */
e2039c7a 354 if (relayd_id != (uint64_t) -1ULL) {
d771f832
DG
355 use_relayd = 1;
356 }
357
358 if (use_relayd) {
10a50311 359 ret = consumer_send_relayd_stream(metadata_stream, path);
e2039c7a 360 if (ret < 0) {
d771f832 361 goto error;
e2039c7a 362 }
e2039c7a
JD
363 } else {
364 ret = utils_create_stream_file(path, metadata_stream->name,
365 metadata_stream->chan->tracefile_size,
366 metadata_stream->tracefile_count_current,
309167d2 367 metadata_stream->uid, metadata_stream->gid, NULL);
e2039c7a 368 if (ret < 0) {
d771f832 369 goto error;
e2039c7a
JD
370 }
371 metadata_stream->out_fd = ret;
07b86b52 372 }
07b86b52 373
d771f832 374 do {
9ce5646a
MD
375 health_code_update();
376
d771f832
DG
377 ret_read = lttng_kconsumer_read_subbuffer(metadata_stream, ctx);
378 if (ret_read < 0) {
56591bac 379 if (ret_read != -EAGAIN) {
6a00837f 380 ERR("Kernel snapshot reading metadata subbuffer (ret: %zd)",
d771f832
DG
381 ret_read);
382 goto error;
07b86b52 383 }
d771f832 384 /* ret_read is negative at this point so we will exit the loop. */
07b86b52
JD
385 continue;
386 }
d771f832 387 } while (ret_read >= 0);
07b86b52 388
d771f832
DG
389 if (use_relayd) {
390 close_relayd_stream(metadata_stream);
391 metadata_stream->net_seq_idx = (uint64_t) -1ULL;
392 } else {
fdf9986c
MD
393 if (metadata_stream->out_fd >= 0) {
394 ret = close(metadata_stream->out_fd);
395 if (ret < 0) {
396 PERROR("Kernel consumer snapshot metadata close out_fd");
397 /*
398 * Don't go on error here since the snapshot was successful at this
399 * point but somehow the close failed.
400 */
401 }
402 metadata_stream->out_fd = -1;
e2039c7a 403 }
e2039c7a
JD
404 }
405
07b86b52 406 ret = 0;
d771f832 407
cf53a8a6
JD
408 cds_list_del(&metadata_stream->send_node);
409 consumer_stream_destroy(metadata_stream, NULL);
410 metadata_channel->metadata_stream = NULL;
d771f832 411error:
07b86b52
JD
412 rcu_read_unlock();
413 return ret;
414}
415
1803a064
MD
416/*
417 * Receive command from session daemon and process it.
418 *
419 * Return 1 on success else a negative value or 0.
420 */
3bd1e081
MD
421int lttng_kconsumer_recv_cmd(struct lttng_consumer_local_data *ctx,
422 int sock, struct pollfd *consumer_sockpoll)
423{
424 ssize_t ret;
0c759fc9 425 enum lttcomm_return_code ret_code = LTTCOMM_CONSUMERD_SUCCESS;
3bd1e081
MD
426 struct lttcomm_consumer_msg msg;
427
9ce5646a
MD
428 health_code_update();
429
3bd1e081
MD
430 ret = lttcomm_recv_unix_sock(sock, &msg, sizeof(msg));
431 if (ret != sizeof(msg)) {
1803a064 432 if (ret > 0) {
c6857fcf 433 lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_ERROR_RECV_CMD);
1803a064
MD
434 ret = -1;
435 }
3bd1e081
MD
436 return ret;
437 }
9ce5646a
MD
438
439 health_code_update();
440
84382d49
MD
441 /* Deprecated command */
442 assert(msg.cmd_type != LTTNG_CONSUMER_STOP);
3bd1e081 443
9ce5646a
MD
444 health_code_update();
445
b0b335c8
MD
446 /* relayd needs RCU read-side protection */
447 rcu_read_lock();
448
3bd1e081 449 switch (msg.cmd_type) {
00e2e675
DG
450 case LTTNG_CONSUMER_ADD_RELAYD_SOCKET:
451 {
f50f23d9 452 /* Session daemon status message are handled in the following call. */
7735ef9e
DG
453 ret = consumer_add_relayd_socket(msg.u.relayd_sock.net_index,
454 msg.u.relayd_sock.type, ctx, sock, consumer_sockpoll,
d3e2ba59
JD
455 &msg.u.relayd_sock.sock, msg.u.relayd_sock.session_id,
456 msg.u.relayd_sock.relayd_session_id);
00e2e675
DG
457 goto end_nosignal;
458 }
3bd1e081
MD
459 case LTTNG_CONSUMER_ADD_CHANNEL:
460 {
461 struct lttng_consumer_channel *new_channel;
e43c41c5 462 int ret_recv;
3bd1e081 463
9ce5646a
MD
464 health_code_update();
465
f50f23d9
DG
466 /* First send a status message before receiving the fds. */
467 ret = consumer_send_status_msg(sock, ret_code);
468 if (ret < 0) {
469 /* Somehow, the session daemon is not responding anymore. */
1803a064 470 goto error_fatal;
f50f23d9 471 }
9ce5646a
MD
472
473 health_code_update();
474
d88aee68 475 DBG("consumer_add_channel %" PRIu64, msg.u.channel.channel_key);
3bd1e081 476 new_channel = consumer_allocate_channel(msg.u.channel.channel_key,
ffe60014
DG
477 msg.u.channel.session_id, msg.u.channel.pathname,
478 msg.u.channel.name, msg.u.channel.uid, msg.u.channel.gid,
1624d5b7
JD
479 msg.u.channel.relayd_id, msg.u.channel.output,
480 msg.u.channel.tracefile_size,
1950109e 481 msg.u.channel.tracefile_count, 0,
ecc48a90
JD
482 msg.u.channel.monitor,
483 msg.u.channel.live_timer_interval);
3bd1e081 484 if (new_channel == NULL) {
f73fabfd 485 lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_OUTFD_ERROR);
3bd1e081
MD
486 goto end_nosignal;
487 }
ffe60014 488 new_channel->nb_init_stream_left = msg.u.channel.nb_init_streams;
95a1109b
JD
489 switch (msg.u.channel.output) {
490 case LTTNG_EVENT_SPLICE:
491 new_channel->output = CONSUMER_CHANNEL_SPLICE;
492 break;
493 case LTTNG_EVENT_MMAP:
494 new_channel->output = CONSUMER_CHANNEL_MMAP;
495 break;
496 default:
497 ERR("Channel output unknown %d", msg.u.channel.output);
498 goto end_nosignal;
499 }
ffe60014
DG
500
501 /* Translate and save channel type. */
502 switch (msg.u.channel.type) {
503 case CONSUMER_CHANNEL_TYPE_DATA:
504 case CONSUMER_CHANNEL_TYPE_METADATA:
505 new_channel->type = msg.u.channel.type;
506 break;
507 default:
508 assert(0);
509 goto end_nosignal;
510 };
511
9ce5646a
MD
512 health_code_update();
513
3bd1e081 514 if (ctx->on_recv_channel != NULL) {
e43c41c5
JD
515 ret_recv = ctx->on_recv_channel(new_channel);
516 if (ret_recv == 0) {
517 ret = consumer_add_channel(new_channel, ctx);
518 } else if (ret_recv < 0) {
3bd1e081
MD
519 goto end_nosignal;
520 }
521 } else {
e43c41c5 522 ret = consumer_add_channel(new_channel, ctx);
3bd1e081 523 }
94d49140
JD
524 if (CONSUMER_CHANNEL_TYPE_DATA) {
525 consumer_timer_live_start(new_channel,
526 msg.u.channel.live_timer_interval);
527 }
e43c41c5 528
9ce5646a
MD
529 health_code_update();
530
e43c41c5 531 /* If we received an error in add_channel, we need to report it. */
821fffb2 532 if (ret < 0) {
1803a064
MD
533 ret = consumer_send_status_msg(sock, ret);
534 if (ret < 0) {
535 goto error_fatal;
536 }
e43c41c5
JD
537 goto end_nosignal;
538 }
539
3bd1e081
MD
540 goto end_nosignal;
541 }
542 case LTTNG_CONSUMER_ADD_STREAM:
543 {
dae10966
DG
544 int fd;
545 struct lttng_pipe *stream_pipe;
00e2e675 546 struct lttng_consumer_stream *new_stream;
ffe60014 547 struct lttng_consumer_channel *channel;
c80048c6 548 int alloc_ret = 0;
3bd1e081 549
ffe60014
DG
550 /*
551 * Get stream's channel reference. Needed when adding the stream to the
552 * global hash table.
553 */
554 channel = consumer_find_channel(msg.u.stream.channel_key);
555 if (!channel) {
556 /*
557 * We could not find the channel. Can happen if cpu hotplug
558 * happens while tearing down.
559 */
d88aee68 560 ERR("Unable to find channel key %" PRIu64, msg.u.stream.channel_key);
e462382a 561 ret_code = LTTCOMM_CONSUMERD_CHAN_NOT_FOUND;
ffe60014
DG
562 }
563
9ce5646a
MD
564 health_code_update();
565
f50f23d9
DG
566 /* First send a status message before receiving the fds. */
567 ret = consumer_send_status_msg(sock, ret_code);
1803a064 568 if (ret < 0) {
d771f832 569 /* Somehow, the session daemon is not responding anymore. */
1803a064
MD
570 goto error_fatal;
571 }
9ce5646a
MD
572
573 health_code_update();
574
0c759fc9 575 if (ret_code != LTTCOMM_CONSUMERD_SUCCESS) {
d771f832 576 /* Channel was not found. */
f50f23d9
DG
577 goto end_nosignal;
578 }
579
d771f832 580 /* Blocking call */
9ce5646a
MD
581 health_poll_entry();
582 ret = lttng_consumer_poll_socket(consumer_sockpoll);
583 health_poll_exit();
84382d49
MD
584 if (ret) {
585 goto error_fatal;
3bd1e081 586 }
00e2e675 587
9ce5646a
MD
588 health_code_update();
589
00e2e675 590 /* Get stream file descriptor from socket */
f2fc6720
MD
591 ret = lttcomm_recv_fds_unix_sock(sock, &fd, 1);
592 if (ret != sizeof(fd)) {
f73fabfd 593 lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_ERROR_RECV_FD);
3f8e211f 594 rcu_read_unlock();
3bd1e081
MD
595 return ret;
596 }
3bd1e081 597
9ce5646a
MD
598 health_code_update();
599
f50f23d9
DG
600 /*
601 * Send status code to session daemon only if the recv works. If the
602 * above recv() failed, the session daemon is notified through the
603 * error socket and the teardown is eventually done.
604 */
605 ret = consumer_send_status_msg(sock, ret_code);
606 if (ret < 0) {
607 /* Somehow, the session daemon is not responding anymore. */
608 goto end_nosignal;
609 }
610
9ce5646a
MD
611 health_code_update();
612
ffe60014
DG
613 new_stream = consumer_allocate_stream(channel->key,
614 fd,
615 LTTNG_CONSUMER_ACTIVE_STREAM,
616 channel->name,
617 channel->uid,
618 channel->gid,
619 channel->relayd_id,
620 channel->session_id,
621 msg.u.stream.cpu,
622 &alloc_ret,
4891ece8
DG
623 channel->type,
624 channel->monitor);
3bd1e081 625 if (new_stream == NULL) {
c80048c6
MD
626 switch (alloc_ret) {
627 case -ENOMEM:
628 case -EINVAL:
629 default:
630 lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_OUTFD_ERROR);
631 break;
c80048c6 632 }
3f8e211f 633 goto end_nosignal;
3bd1e081 634 }
d771f832 635
ffe60014
DG
636 new_stream->chan = channel;
637 new_stream->wait_fd = fd;
07b86b52
JD
638 switch (channel->output) {
639 case CONSUMER_CHANNEL_SPLICE:
640 new_stream->output = LTTNG_EVENT_SPLICE;
a2361a61
JD
641 ret = utils_create_pipe(new_stream->splice_pipe);
642 if (ret < 0) {
643 goto end_nosignal;
644 }
07b86b52
JD
645 break;
646 case CONSUMER_CHANNEL_MMAP:
647 new_stream->output = LTTNG_EVENT_MMAP;
648 break;
649 default:
650 ERR("Stream output unknown %d", channel->output);
651 goto end_nosignal;
652 }
00e2e675 653
a0c83db9
DG
654 /*
655 * We've just assigned the channel to the stream so increment the
07b86b52
JD
656 * refcount right now. We don't need to increment the refcount for
657 * streams in no monitor because we handle manually the cleanup of
658 * those. It is very important to make sure there is NO prior
659 * consumer_del_stream() calls or else the refcount will be unbalanced.
a0c83db9 660 */
07b86b52
JD
661 if (channel->monitor) {
662 uatomic_inc(&new_stream->chan->refcount);
663 }
9d9353f9 664
fb3a43a9
DG
665 /*
666 * The buffer flush is done on the session daemon side for the kernel
667 * so no need for the stream "hangup_flush_done" variable to be
668 * tracked. This is important for a kernel stream since we don't rely
669 * on the flush state of the stream to read data. It's not the case for
670 * user space tracing.
671 */
672 new_stream->hangup_flush_done = 0;
673
9ce5646a
MD
674 health_code_update();
675
633d0084
DG
676 if (ctx->on_recv_stream) {
677 ret = ctx->on_recv_stream(new_stream);
678 if (ret < 0) {
d771f832 679 consumer_stream_free(new_stream);
633d0084 680 goto end_nosignal;
fb3a43a9 681 }
633d0084 682 }
fb3a43a9 683
9ce5646a
MD
684 health_code_update();
685
07b86b52
JD
686 if (new_stream->metadata_flag) {
687 channel->metadata_stream = new_stream;
688 }
689
2bba9e53
DG
690 /* Do not monitor this stream. */
691 if (!channel->monitor) {
5eecee74 692 DBG("Kernel consumer add stream %s in no monitor mode with "
6dc3064a 693 "relayd id %" PRIu64, new_stream->name,
5eecee74 694 new_stream->net_seq_idx);
10a50311 695 cds_list_add(&new_stream->send_node, &channel->streams.head);
6dc3064a
DG
696 break;
697 }
698
e1b71bdc
DG
699 /* Send stream to relayd if the stream has an ID. */
700 if (new_stream->net_seq_idx != (uint64_t) -1ULL) {
194ee077
DG
701 ret = consumer_send_relayd_stream(new_stream,
702 new_stream->chan->pathname);
e1b71bdc
DG
703 if (ret < 0) {
704 consumer_stream_free(new_stream);
705 goto end_nosignal;
706 }
e2039c7a
JD
707 }
708
50f8ae69 709 /* Get the right pipe where the stream will be sent. */
633d0084 710 if (new_stream->metadata_flag) {
5ab66908
MD
711 ret = consumer_add_metadata_stream(new_stream);
712 if (ret) {
713 ERR("Consumer add metadata stream %" PRIu64 " failed. Continuing",
714 new_stream->key);
715 consumer_stream_free(new_stream);
716 goto end_nosignal;
717 }
dae10966 718 stream_pipe = ctx->consumer_metadata_pipe;
3bd1e081 719 } else {
5ab66908
MD
720 ret = consumer_add_data_stream(new_stream);
721 if (ret) {
722 ERR("Consumer add stream %" PRIu64 " failed. Continuing",
723 new_stream->key);
724 consumer_stream_free(new_stream);
725 goto end_nosignal;
726 }
dae10966 727 stream_pipe = ctx->consumer_data_pipe;
50f8ae69
DG
728 }
729
5ab66908
MD
730 /* Vitible to other threads */
731 new_stream->globally_visible = 1;
732
9ce5646a
MD
733 health_code_update();
734
dae10966 735 ret = lttng_pipe_write(stream_pipe, &new_stream, sizeof(new_stream));
50f8ae69 736 if (ret < 0) {
dae10966 737 ERR("Consumer write %s stream to pipe %d",
50f8ae69 738 new_stream->metadata_flag ? "metadata" : "data",
dae10966 739 lttng_pipe_get_writefd(stream_pipe));
5ab66908
MD
740 if (new_stream->metadata_flag) {
741 consumer_del_stream_for_metadata(new_stream);
742 } else {
743 consumer_del_stream_for_data(new_stream);
744 }
50f8ae69 745 goto end_nosignal;
3bd1e081 746 }
00e2e675 747
50f8ae69 748 DBG("Kernel consumer ADD_STREAM %s (fd: %d) with relayd id %" PRIu64,
ffe60014 749 new_stream->name, fd, new_stream->relayd_stream_id);
3bd1e081
MD
750 break;
751 }
a4baae1b
JD
752 case LTTNG_CONSUMER_STREAMS_SENT:
753 {
754 struct lttng_consumer_channel *channel;
755
756 /*
757 * Get stream's channel reference. Needed when adding the stream to the
758 * global hash table.
759 */
760 channel = consumer_find_channel(msg.u.sent_streams.channel_key);
761 if (!channel) {
762 /*
763 * We could not find the channel. Can happen if cpu hotplug
764 * happens while tearing down.
765 */
766 ERR("Unable to find channel key %" PRIu64,
767 msg.u.sent_streams.channel_key);
e462382a 768 ret_code = LTTCOMM_CONSUMERD_CHAN_NOT_FOUND;
a4baae1b
JD
769 }
770
771 health_code_update();
772
773 /*
774 * Send status code to session daemon.
775 */
776 ret = consumer_send_status_msg(sock, ret_code);
f261ad0a 777 if (ret < 0 || ret_code != LTTCOMM_CONSUMERD_SUCCESS) {
a4baae1b
JD
778 /* Somehow, the session daemon is not responding anymore. */
779 goto end_nosignal;
780 }
781
782 health_code_update();
783
784 /*
785 * We should not send this message if we don't monitor the
786 * streams in this channel.
787 */
788 if (!channel->monitor) {
789 break;
790 }
791
792 health_code_update();
793 /* Send stream to relayd if the stream has an ID. */
794 if (msg.u.sent_streams.net_seq_idx != (uint64_t) -1ULL) {
795 ret = consumer_send_relayd_streams_sent(
796 msg.u.sent_streams.net_seq_idx);
797 if (ret < 0) {
798 goto end_nosignal;
799 }
800 }
801 break;
802 }
3bd1e081
MD
803 case LTTNG_CONSUMER_UPDATE_STREAM:
804 {
3f8e211f
DG
805 rcu_read_unlock();
806 return -ENOSYS;
807 }
808 case LTTNG_CONSUMER_DESTROY_RELAYD:
809 {
a6ba4fe1 810 uint64_t index = msg.u.destroy_relayd.net_seq_idx;
3f8e211f
DG
811 struct consumer_relayd_sock_pair *relayd;
812
a6ba4fe1 813 DBG("Kernel consumer destroying relayd %" PRIu64, index);
3f8e211f
DG
814
815 /* Get relayd reference if exists. */
a6ba4fe1 816 relayd = consumer_find_relayd(index);
3f8e211f 817 if (relayd == NULL) {
3448e266 818 DBG("Unable to find relayd %" PRIu64, index);
e462382a 819 ret_code = LTTCOMM_CONSUMERD_RELAYD_FAIL;
3bd1e081 820 }
3f8e211f 821
a6ba4fe1
DG
822 /*
823 * Each relayd socket pair has a refcount of stream attached to it
824 * which tells if the relayd is still active or not depending on the
825 * refcount value.
826 *
827 * This will set the destroy flag of the relayd object and destroy it
828 * if the refcount reaches zero when called.
829 *
830 * The destroy can happen either here or when a stream fd hangs up.
831 */
f50f23d9
DG
832 if (relayd) {
833 consumer_flag_relayd_for_destroy(relayd);
834 }
835
9ce5646a
MD
836 health_code_update();
837
f50f23d9
DG
838 ret = consumer_send_status_msg(sock, ret_code);
839 if (ret < 0) {
840 /* Somehow, the session daemon is not responding anymore. */
1803a064 841 goto error_fatal;
f50f23d9 842 }
3f8e211f 843
3f8e211f 844 goto end_nosignal;
3bd1e081 845 }
6d805429 846 case LTTNG_CONSUMER_DATA_PENDING:
53632229 847 {
c8f59ee5 848 int32_t ret;
6d805429 849 uint64_t id = msg.u.data_pending.session_id;
c8f59ee5 850
6d805429 851 DBG("Kernel consumer data pending command for id %" PRIu64, id);
c8f59ee5 852
6d805429 853 ret = consumer_data_pending(id);
c8f59ee5 854
9ce5646a
MD
855 health_code_update();
856
c8f59ee5
DG
857 /* Send back returned value to session daemon */
858 ret = lttcomm_send_unix_sock(sock, &ret, sizeof(ret));
859 if (ret < 0) {
6d805429 860 PERROR("send data pending ret code");
1803a064 861 goto error_fatal;
c8f59ee5 862 }
f50f23d9
DG
863
864 /*
865 * No need to send back a status message since the data pending
866 * returned value is the response.
867 */
c8f59ee5 868 break;
53632229 869 }
6dc3064a
DG
870 case LTTNG_CONSUMER_SNAPSHOT_CHANNEL:
871 {
07b86b52
JD
872 if (msg.u.snapshot_channel.metadata == 1) {
873 ret = lttng_kconsumer_snapshot_metadata(msg.u.snapshot_channel.key,
e2039c7a
JD
874 msg.u.snapshot_channel.pathname,
875 msg.u.snapshot_channel.relayd_id, ctx);
07b86b52
JD
876 if (ret < 0) {
877 ERR("Snapshot metadata failed");
e462382a 878 ret_code = LTTCOMM_CONSUMERD_ERROR_METADATA;
07b86b52
JD
879 }
880 } else {
881 ret = lttng_kconsumer_snapshot_channel(msg.u.snapshot_channel.key,
882 msg.u.snapshot_channel.pathname,
5c786ded 883 msg.u.snapshot_channel.relayd_id,
d07ceecd 884 msg.u.snapshot_channel.nb_packets_per_stream,
5c786ded 885 ctx);
07b86b52
JD
886 if (ret < 0) {
887 ERR("Snapshot channel failed");
e462382a 888 ret_code = LTTCOMM_CONSUMERD_CHAN_NOT_FOUND;
07b86b52
JD
889 }
890 }
891
9ce5646a
MD
892 health_code_update();
893
6dc3064a
DG
894 ret = consumer_send_status_msg(sock, ret_code);
895 if (ret < 0) {
896 /* Somehow, the session daemon is not responding anymore. */
897 goto end_nosignal;
898 }
899 break;
900 }
07b86b52
JD
901 case LTTNG_CONSUMER_DESTROY_CHANNEL:
902 {
903 uint64_t key = msg.u.destroy_channel.key;
904 struct lttng_consumer_channel *channel;
905
906 channel = consumer_find_channel(key);
907 if (!channel) {
908 ERR("Kernel consumer destroy channel %" PRIu64 " not found", key);
e462382a 909 ret_code = LTTCOMM_CONSUMERD_CHAN_NOT_FOUND;
07b86b52
JD
910 }
911
9ce5646a
MD
912 health_code_update();
913
07b86b52
JD
914 ret = consumer_send_status_msg(sock, ret_code);
915 if (ret < 0) {
916 /* Somehow, the session daemon is not responding anymore. */
917 goto end_nosignal;
918 }
919
9ce5646a
MD
920 health_code_update();
921
15dc512a
DG
922 /* Stop right now if no channel was found. */
923 if (!channel) {
924 goto end_nosignal;
925 }
926
07b86b52
JD
927 /*
928 * This command should ONLY be issued for channel with streams set in
929 * no monitor mode.
930 */
931 assert(!channel->monitor);
932
933 /*
934 * The refcount should ALWAYS be 0 in the case of a channel in no
935 * monitor mode.
936 */
937 assert(!uatomic_sub_return(&channel->refcount, 1));
938
939 consumer_del_channel(channel);
940
941 goto end_nosignal;
942 }
3bd1e081 943 default:
3f8e211f 944 goto end_nosignal;
3bd1e081 945 }
3f8e211f 946
3bd1e081 947end_nosignal:
b0b335c8 948 rcu_read_unlock();
4cbc1a04
DG
949
950 /*
951 * Return 1 to indicate success since the 0 value can be a socket
952 * shutdown during the recv() or send() call.
953 */
9ce5646a 954 health_code_update();
4cbc1a04 955 return 1;
1803a064
MD
956
957error_fatal:
958 rcu_read_unlock();
959 /* This will issue a consumer stop. */
960 return -1;
3bd1e081 961}
d41f73b7 962
309167d2
JD
963/*
964 * Populate index values of a kernel stream. Values are set in big endian order.
965 *
966 * Return 0 on success or else a negative value.
967 */
50adc264 968static int get_index_values(struct ctf_packet_index *index, int infd)
309167d2
JD
969{
970 int ret;
971
972 ret = kernctl_get_timestamp_begin(infd, &index->timestamp_begin);
973 if (ret < 0) {
974 PERROR("kernctl_get_timestamp_begin");
975 goto error;
976 }
977 index->timestamp_begin = htobe64(index->timestamp_begin);
978
979 ret = kernctl_get_timestamp_end(infd, &index->timestamp_end);
980 if (ret < 0) {
981 PERROR("kernctl_get_timestamp_end");
982 goto error;
983 }
984 index->timestamp_end = htobe64(index->timestamp_end);
985
986 ret = kernctl_get_events_discarded(infd, &index->events_discarded);
987 if (ret < 0) {
988 PERROR("kernctl_get_events_discarded");
989 goto error;
990 }
991 index->events_discarded = htobe64(index->events_discarded);
992
993 ret = kernctl_get_content_size(infd, &index->content_size);
994 if (ret < 0) {
995 PERROR("kernctl_get_content_size");
996 goto error;
997 }
998 index->content_size = htobe64(index->content_size);
999
1000 ret = kernctl_get_packet_size(infd, &index->packet_size);
1001 if (ret < 0) {
1002 PERROR("kernctl_get_packet_size");
1003 goto error;
1004 }
1005 index->packet_size = htobe64(index->packet_size);
1006
1007 ret = kernctl_get_stream_id(infd, &index->stream_id);
1008 if (ret < 0) {
1009 PERROR("kernctl_get_stream_id");
1010 goto error;
1011 }
1012 index->stream_id = htobe64(index->stream_id);
1013
1014error:
1015 return ret;
1016}
94d49140
JD
1017/*
1018 * Sync metadata meaning request them to the session daemon and snapshot to the
1019 * metadata thread can consumer them.
1020 *
1021 * Metadata stream lock MUST be acquired.
1022 *
1023 * Return 0 if new metadatda is available, EAGAIN if the metadata stream
1024 * is empty or a negative value on error.
1025 */
1026int lttng_kconsumer_sync_metadata(struct lttng_consumer_stream *metadata)
1027{
1028 int ret;
1029
1030 assert(metadata);
1031
1032 ret = kernctl_buffer_flush(metadata->wait_fd);
1033 if (ret < 0) {
1034 ERR("Failed to flush kernel stream");
1035 goto end;
1036 }
1037
1038 ret = kernctl_snapshot(metadata->wait_fd);
1039 if (ret < 0) {
1040 if (errno != EAGAIN) {
1041 ERR("Sync metadata, taking kernel snapshot failed.");
1042 goto end;
1043 }
1044 DBG("Sync metadata, no new kernel metadata");
1045 /* No new metadata, exit. */
1046 ret = ENODATA;
1047 goto end;
1048 }
1049
1050end:
1051 return ret;
1052}
309167d2 1053
d41f73b7
MD
1054/*
1055 * Consume data on a file descriptor and write it on a trace file.
1056 */
4078b776 1057ssize_t lttng_kconsumer_read_subbuffer(struct lttng_consumer_stream *stream,
d41f73b7
MD
1058 struct lttng_consumer_local_data *ctx)
1059{
1d4dfdef 1060 unsigned long len, subbuf_size, padding;
1c20f0e2 1061 int err, write_index = 1;
4078b776 1062 ssize_t ret = 0;
d41f73b7 1063 int infd = stream->wait_fd;
50adc264 1064 struct ctf_packet_index index;
d41f73b7
MD
1065
1066 DBG("In read_subbuffer (infd : %d)", infd);
309167d2 1067
d41f73b7
MD
1068 /* Get the next subbuffer */
1069 err = kernctl_get_next_subbuf(infd);
1070 if (err != 0) {
d41f73b7
MD
1071 /*
1072 * This is a debug message even for single-threaded consumer,
1073 * because poll() have more relaxed criterions than get subbuf,
1074 * so get_subbuf may fail for short race windows where poll()
1075 * would issue wakeups.
1076 */
1077 DBG("Reserving sub buffer failed (everything is normal, "
1078 "it is due to concurrency)");
56591bac 1079 ret = -errno;
d41f73b7
MD
1080 goto end;
1081 }
1082
1d4dfdef
DG
1083 /* Get the full subbuffer size including padding */
1084 err = kernctl_get_padded_subbuf_size(infd, &len);
1085 if (err != 0) {
5a510c9f 1086 PERROR("Getting sub-buffer len failed.");
8265f19e
MD
1087 err = kernctl_put_subbuf(infd);
1088 if (err != 0) {
1089 if (errno == EFAULT) {
5a510c9f 1090 PERROR("Error in unreserving sub buffer\n");
8265f19e
MD
1091 } else if (errno == EIO) {
1092 /* Should never happen with newer LTTng versions */
5a510c9f 1093 PERROR("Reader has been pushed by the writer, last sub-buffer corrupted.");
8265f19e
MD
1094 }
1095 ret = -errno;
1096 goto end;
1097 }
56591bac 1098 ret = -errno;
1d4dfdef
DG
1099 goto end;
1100 }
1101
1c20f0e2 1102 if (!stream->metadata_flag) {
309167d2
JD
1103 ret = get_index_values(&index, infd);
1104 if (ret < 0) {
8265f19e
MD
1105 err = kernctl_put_subbuf(infd);
1106 if (err != 0) {
1107 if (errno == EFAULT) {
5a510c9f 1108 PERROR("Error in unreserving sub buffer\n");
8265f19e
MD
1109 } else if (errno == EIO) {
1110 /* Should never happen with newer LTTng versions */
5a510c9f 1111 PERROR("Reader has been pushed by the writer, last sub-buffer corrupted.");
8265f19e
MD
1112 }
1113 ret = -errno;
1114 goto end;
1115 }
309167d2
JD
1116 goto end;
1117 }
1c20f0e2
JD
1118 } else {
1119 write_index = 0;
309167d2
JD
1120 }
1121
ffe60014 1122 switch (stream->chan->output) {
07b86b52 1123 case CONSUMER_CHANNEL_SPLICE:
1d4dfdef
DG
1124 /*
1125 * XXX: The lttng-modules splice "actor" does not handle copying
1126 * partial pages hence only using the subbuffer size without the
1127 * padding makes the splice fail.
1128 */
1129 subbuf_size = len;
1130 padding = 0;
1131
1132 /* splice the subbuffer to the tracefile */
91dfef6e 1133 ret = lttng_consumer_on_read_subbuffer_splice(ctx, stream, subbuf_size,
309167d2 1134 padding, &index);
91dfef6e
DG
1135 /*
1136 * XXX: Splice does not support network streaming so the return value
1137 * is simply checked against subbuf_size and not like the mmap() op.
1138 */
1d4dfdef
DG
1139 if (ret != subbuf_size) {
1140 /*
1141 * display the error but continue processing to try
1142 * to release the subbuffer
1143 */
1144 ERR("Error splicing to tracefile (ret: %zd != len: %lu)",
1145 ret, subbuf_size);
309167d2 1146 write_index = 0;
1d4dfdef
DG
1147 }
1148 break;
07b86b52 1149 case CONSUMER_CHANNEL_MMAP:
1d4dfdef
DG
1150 /* Get subbuffer size without padding */
1151 err = kernctl_get_subbuf_size(infd, &subbuf_size);
1152 if (err != 0) {
5a510c9f 1153 PERROR("Getting sub-buffer len failed.");
8265f19e
MD
1154 err = kernctl_put_subbuf(infd);
1155 if (err != 0) {
1156 if (errno == EFAULT) {
5a510c9f 1157 PERROR("Error in unreserving sub buffer\n");
8265f19e
MD
1158 } else if (errno == EIO) {
1159 /* Should never happen with newer LTTng versions */
5a510c9f 1160 PERROR("Reader has been pushed by the writer, last sub-buffer corrupted.");
8265f19e
MD
1161 }
1162 ret = -errno;
1163 goto end;
1164 }
56591bac 1165 ret = -errno;
1d4dfdef
DG
1166 goto end;
1167 }
47e81c02 1168
1d4dfdef
DG
1169 /* Make sure the tracer is not gone mad on us! */
1170 assert(len >= subbuf_size);
1171
1172 padding = len - subbuf_size;
1173
1174 /* write the subbuffer to the tracefile */
91dfef6e 1175 ret = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, subbuf_size,
309167d2 1176 padding, &index);
91dfef6e
DG
1177 /*
1178 * The mmap operation should write subbuf_size amount of data when
1179 * network streaming or the full padding (len) size when we are _not_
1180 * streaming.
1181 */
d88aee68
DG
1182 if ((ret != subbuf_size && stream->net_seq_idx != (uint64_t) -1ULL) ||
1183 (ret != len && stream->net_seq_idx == (uint64_t) -1ULL)) {
1d4dfdef 1184 /*
91dfef6e 1185 * Display the error but continue processing to try to release the
2336629e
DG
1186 * subbuffer. This is a DBG statement since this is possible to
1187 * happen without being a critical error.
1d4dfdef 1188 */
2336629e 1189 DBG("Error writing to tracefile "
91dfef6e
DG
1190 "(ret: %zd != len: %lu != subbuf_size: %lu)",
1191 ret, len, subbuf_size);
309167d2 1192 write_index = 0;
1d4dfdef
DG
1193 }
1194 break;
1195 default:
1196 ERR("Unknown output method");
56591bac 1197 ret = -EPERM;
d41f73b7
MD
1198 }
1199
1200 err = kernctl_put_next_subbuf(infd);
1201 if (err != 0) {
d41f73b7 1202 if (errno == EFAULT) {
5a510c9f 1203 PERROR("Error in unreserving sub buffer\n");
d41f73b7
MD
1204 } else if (errno == EIO) {
1205 /* Should never happen with newer LTTng versions */
5a510c9f 1206 PERROR("Reader has been pushed by the writer, last sub-buffer corrupted.");
d41f73b7 1207 }
56591bac 1208 ret = -errno;
d41f73b7
MD
1209 goto end;
1210 }
1211
309167d2 1212 /* Write index if needed. */
1c20f0e2
JD
1213 if (!write_index) {
1214 goto end;
1215 }
1216
94d49140
JD
1217 if (stream->chan->live_timer_interval && !stream->metadata_flag) {
1218 /*
1219 * In live, block until all the metadata is sent.
1220 */
1221 err = consumer_stream_sync_metadata(ctx, stream->session_id);
1222 if (err < 0) {
1223 goto end;
1224 }
1225 }
1226
1c20f0e2
JD
1227 err = consumer_stream_write_index(stream, &index);
1228 if (err < 0) {
1229 goto end;
309167d2
JD
1230 }
1231
d41f73b7
MD
1232end:
1233 return ret;
1234}
1235
1236int lttng_kconsumer_on_recv_stream(struct lttng_consumer_stream *stream)
1237{
1238 int ret;
ffe60014
DG
1239
1240 assert(stream);
1241
2bba9e53
DG
1242 /*
1243 * Don't create anything if this is set for streaming or should not be
1244 * monitored.
1245 */
1246 if (stream->net_seq_idx == (uint64_t) -1ULL && stream->chan->monitor) {
fe4477ee
JD
1247 ret = utils_create_stream_file(stream->chan->pathname, stream->name,
1248 stream->chan->tracefile_size, stream->tracefile_count_current,
309167d2 1249 stream->uid, stream->gid, NULL);
fe4477ee
JD
1250 if (ret < 0) {
1251 goto error;
1252 }
1253 stream->out_fd = ret;
1254 stream->tracefile_size_current = 0;
309167d2
JD
1255
1256 if (!stream->metadata_flag) {
1257 ret = index_create_file(stream->chan->pathname,
1258 stream->name, stream->uid, stream->gid,
1259 stream->chan->tracefile_size,
1260 stream->tracefile_count_current);
1261 if (ret < 0) {
1262 goto error;
1263 }
1264 stream->index_fd = ret;
1265 }
ffe60014 1266 }
d41f73b7 1267
d41f73b7
MD
1268 if (stream->output == LTTNG_EVENT_MMAP) {
1269 /* get the len of the mmap region */
1270 unsigned long mmap_len;
1271
1272 ret = kernctl_get_mmap_len(stream->wait_fd, &mmap_len);
1273 if (ret != 0) {
ffe60014 1274 PERROR("kernctl_get_mmap_len");
56591bac 1275 ret = -errno;
d41f73b7
MD
1276 goto error_close_fd;
1277 }
1278 stream->mmap_len = (size_t) mmap_len;
1279
ffe60014
DG
1280 stream->mmap_base = mmap(NULL, stream->mmap_len, PROT_READ,
1281 MAP_PRIVATE, stream->wait_fd, 0);
d41f73b7 1282 if (stream->mmap_base == MAP_FAILED) {
ffe60014 1283 PERROR("Error mmaping");
d41f73b7
MD
1284 ret = -1;
1285 goto error_close_fd;
1286 }
1287 }
1288
1289 /* we return 0 to let the library handle the FD internally */
1290 return 0;
1291
1292error_close_fd:
2f225ce2 1293 if (stream->out_fd >= 0) {
d41f73b7
MD
1294 int err;
1295
1296 err = close(stream->out_fd);
1297 assert(!err);
2f225ce2 1298 stream->out_fd = -1;
d41f73b7
MD
1299 }
1300error:
1301 return ret;
1302}
1303
ca22feea
DG
1304/*
1305 * Check if data is still being extracted from the buffers for a specific
4e9a4686
DG
1306 * stream. Consumer data lock MUST be acquired before calling this function
1307 * and the stream lock.
ca22feea 1308 *
6d805429 1309 * Return 1 if the traced data are still getting read else 0 meaning that the
ca22feea
DG
1310 * data is available for trace viewer reading.
1311 */
6d805429 1312int lttng_kconsumer_data_pending(struct lttng_consumer_stream *stream)
ca22feea
DG
1313{
1314 int ret;
1315
1316 assert(stream);
1317
873b9e9a
MD
1318 if (stream->endpoint_status != CONSUMER_ENDPOINT_ACTIVE) {
1319 ret = 0;
1320 goto end;
1321 }
1322
ca22feea
DG
1323 ret = kernctl_get_next_subbuf(stream->wait_fd);
1324 if (ret == 0) {
1325 /* There is still data so let's put back this subbuffer. */
1326 ret = kernctl_put_subbuf(stream->wait_fd);
1327 assert(ret == 0);
6d805429 1328 ret = 1; /* Data is pending */
4e9a4686 1329 goto end;
ca22feea
DG
1330 }
1331
6d805429
DG
1332 /* Data is NOT pending and ready to be read. */
1333 ret = 0;
ca22feea 1334
6efae65e
DG
1335end:
1336 return ret;
ca22feea 1337}
This page took 0.119758 seconds and 4 git commands to generate.