Commit | Line | Data |
---|---|---|
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 | ||
6c1c0768 | 19 | #define _LGPL_SOURCE |
3bd1e081 | 20 | #include <assert.h> |
3bd1e081 MD |
21 | #include <poll.h> |
22 | #include <pthread.h> | |
23 | #include <stdlib.h> | |
24 | #include <string.h> | |
25 | #include <sys/mman.h> | |
26 | #include <sys/socket.h> | |
27 | #include <sys/types.h> | |
77c7c900 | 28 | #include <inttypes.h> |
3bd1e081 | 29 | #include <unistd.h> |
dbb5dfe6 | 30 | #include <sys/stat.h> |
3bd1e081 | 31 | |
51a9e1c7 | 32 | #include <bin/lttng-consumerd/health-consumerd.h> |
990570ed | 33 | #include <common/common.h> |
10a8a223 | 34 | #include <common/kernel-ctl/kernel-ctl.h> |
10a8a223 | 35 | #include <common/sessiond-comm/sessiond-comm.h> |
00e2e675 | 36 | #include <common/sessiond-comm/relayd.h> |
dbb5dfe6 | 37 | #include <common/compat/fcntl.h> |
f263b7fd | 38 | #include <common/compat/endian.h> |
acdb9057 | 39 | #include <common/pipe.h> |
00e2e675 | 40 | #include <common/relayd/relayd.h> |
fe4477ee | 41 | #include <common/utils.h> |
c8fea79c | 42 | #include <common/consumer/consumer-stream.h> |
309167d2 | 43 | #include <common/index/index.h> |
c8fea79c | 44 | #include <common/consumer/consumer-timer.h> |
0857097f | 45 | |
10a8a223 | 46 | #include "kernel-consumer.h" |
3bd1e081 MD |
47 | |
48 | extern struct lttng_consumer_global_data consumer_data; | |
49 | extern int consumer_poll_timeout; | |
50 | extern volatile int consumer_quit; | |
51 | ||
3bd1e081 MD |
52 | /* |
53 | * Take a snapshot for a specific fd | |
54 | * | |
55 | * Returns 0 on success, < 0 on error | |
56 | */ | |
ffe60014 | 57 | int lttng_kconsumer_take_snapshot(struct lttng_consumer_stream *stream) |
3bd1e081 MD |
58 | { |
59 | int ret = 0; | |
60 | int infd = stream->wait_fd; | |
61 | ||
62 | ret = kernctl_snapshot(infd); | |
63 | if (ret != 0) { | |
5a510c9f | 64 | PERROR("Getting sub-buffer snapshot."); |
56591bac | 65 | ret = -errno; |
3bd1e081 MD |
66 | } |
67 | ||
68 | return ret; | |
69 | } | |
70 | ||
71 | /* | |
72 | * Get the produced position | |
73 | * | |
74 | * Returns 0 on success, < 0 on error | |
75 | */ | |
ffe60014 | 76 | int lttng_kconsumer_get_produced_snapshot(struct lttng_consumer_stream *stream, |
3bd1e081 MD |
77 | unsigned long *pos) |
78 | { | |
79 | int ret; | |
80 | int infd = stream->wait_fd; | |
81 | ||
82 | ret = kernctl_snapshot_get_produced(infd, pos); | |
83 | if (ret != 0) { | |
5a510c9f | 84 | PERROR("kernctl_snapshot_get_produced"); |
56591bac | 85 | ret = -errno; |
3bd1e081 MD |
86 | } |
87 | ||
88 | return ret; | |
89 | } | |
90 | ||
07b86b52 JD |
91 | /* |
92 | * Get the consumerd position | |
93 | * | |
94 | * Returns 0 on success, < 0 on error | |
95 | */ | |
96 | int lttng_kconsumer_get_consumed_snapshot(struct lttng_consumer_stream *stream, | |
97 | unsigned long *pos) | |
98 | { | |
99 | int ret; | |
100 | int infd = stream->wait_fd; | |
101 | ||
102 | ret = kernctl_snapshot_get_consumed(infd, pos); | |
103 | if (ret != 0) { | |
5a510c9f | 104 | PERROR("kernctl_snapshot_get_consumed"); |
56591bac | 105 | ret = -errno; |
07b86b52 JD |
106 | } |
107 | ||
108 | return ret; | |
109 | } | |
110 | ||
07b86b52 JD |
111 | /* |
112 | * Take a snapshot of all the stream of a channel | |
113 | * | |
114 | * Returns 0 on success, < 0 on error | |
115 | */ | |
116 | int lttng_kconsumer_snapshot_channel(uint64_t key, char *path, | |
d07ceecd | 117 | uint64_t relayd_id, uint64_t nb_packets_per_stream, |
5c786ded | 118 | struct lttng_consumer_local_data *ctx) |
07b86b52 JD |
119 | { |
120 | int ret; | |
07b86b52 JD |
121 | struct lttng_consumer_channel *channel; |
122 | struct lttng_consumer_stream *stream; | |
123 | ||
6a00837f | 124 | DBG("Kernel consumer snapshot channel %" PRIu64, key); |
07b86b52 JD |
125 | |
126 | rcu_read_lock(); | |
127 | ||
128 | channel = consumer_find_channel(key); | |
129 | if (!channel) { | |
6a00837f | 130 | ERR("No channel found for key %" PRIu64, key); |
07b86b52 JD |
131 | ret = -1; |
132 | goto end; | |
133 | } | |
134 | ||
135 | /* Splice is not supported yet for channel snapshot. */ | |
136 | if (channel->output != CONSUMER_CHANNEL_MMAP) { | |
137 | ERR("Unsupported output %d", channel->output); | |
138 | ret = -1; | |
139 | goto end; | |
140 | } | |
141 | ||
10a50311 | 142 | cds_list_for_each_entry(stream, &channel->streams.head, send_node) { |
9ffd0032 | 143 | unsigned long consumed_pos, produced_pos; |
9ce5646a MD |
144 | |
145 | health_code_update(); | |
146 | ||
07b86b52 JD |
147 | /* |
148 | * Lock stream because we are about to change its state. | |
149 | */ | |
150 | pthread_mutex_lock(&stream->lock); | |
151 | ||
29decac3 DG |
152 | /* |
153 | * Assign the received relayd ID so we can use it for streaming. The streams | |
154 | * are not visible to anyone so this is OK to change it. | |
155 | */ | |
07b86b52 JD |
156 | stream->net_seq_idx = relayd_id; |
157 | channel->relayd_id = relayd_id; | |
158 | if (relayd_id != (uint64_t) -1ULL) { | |
10a50311 | 159 | ret = consumer_send_relayd_stream(stream, path); |
07b86b52 JD |
160 | if (ret < 0) { |
161 | ERR("sending stream to relayd"); | |
162 | goto end_unlock; | |
163 | } | |
07b86b52 JD |
164 | } else { |
165 | ret = utils_create_stream_file(path, stream->name, | |
10a50311 JD |
166 | stream->chan->tracefile_size, |
167 | stream->tracefile_count_current, | |
309167d2 | 168 | stream->uid, stream->gid, NULL); |
07b86b52 JD |
169 | if (ret < 0) { |
170 | ERR("utils_create_stream_file"); | |
171 | goto end_unlock; | |
172 | } | |
173 | ||
174 | stream->out_fd = ret; | |
175 | stream->tracefile_size_current = 0; | |
176 | ||
81ea21bf MD |
177 | DBG("Kernel consumer snapshot stream %s/%s (%" PRIu64 ")", |
178 | path, stream->name, stream->key); | |
07b86b52 | 179 | } |
601262d6 JD |
180 | if (relayd_id != -1ULL) { |
181 | ret = consumer_send_relayd_streams_sent(relayd_id); | |
182 | if (ret < 0) { | |
183 | ERR("sending streams sent to relayd"); | |
184 | goto end_unlock; | |
185 | } | |
7881b1c4 | 186 | channel->streams_sent_to_relayd = true; |
a4baae1b | 187 | } |
07b86b52 | 188 | |
e49273dc | 189 | ret = kernctl_buffer_flush_empty(stream->wait_fd); |
07b86b52 | 190 | if (ret < 0) { |
e49273dc MD |
191 | /* |
192 | * Doing a buffer flush which does not take into | |
193 | * account empty packets. This is not perfect | |
194 | * for stream intersection, but required as a | |
195 | * fall-back when "flush_empty" is not | |
196 | * implemented by lttng-modules. | |
197 | */ | |
198 | ret = kernctl_buffer_flush(stream->wait_fd); | |
199 | if (ret < 0) { | |
200 | ERR("Failed to flush kernel stream"); | |
201 | goto end_unlock; | |
202 | } | |
07b86b52 JD |
203 | } |
204 | ||
205 | ret = lttng_kconsumer_take_snapshot(stream); | |
206 | if (ret < 0) { | |
207 | ERR("Taking kernel snapshot"); | |
208 | goto end_unlock; | |
209 | } | |
210 | ||
211 | ret = lttng_kconsumer_get_produced_snapshot(stream, &produced_pos); | |
212 | if (ret < 0) { | |
213 | ERR("Produced kernel snapshot position"); | |
214 | goto end_unlock; | |
215 | } | |
216 | ||
217 | ret = lttng_kconsumer_get_consumed_snapshot(stream, &consumed_pos); | |
218 | if (ret < 0) { | |
219 | ERR("Consumerd kernel snapshot position"); | |
220 | goto end_unlock; | |
221 | } | |
222 | ||
223 | if (stream->max_sb_size == 0) { | |
224 | ret = kernctl_get_max_subbuf_size(stream->wait_fd, | |
225 | &stream->max_sb_size); | |
226 | if (ret < 0) { | |
227 | ERR("Getting kernel max_sb_size"); | |
56591bac | 228 | ret = -errno; |
07b86b52 JD |
229 | goto end_unlock; |
230 | } | |
231 | } | |
232 | ||
d07ceecd MD |
233 | consumed_pos = consumer_get_consume_start_pos(consumed_pos, |
234 | produced_pos, nb_packets_per_stream, | |
235 | stream->max_sb_size); | |
5c786ded | 236 | |
07b86b52 JD |
237 | while (consumed_pos < produced_pos) { |
238 | ssize_t read_len; | |
239 | unsigned long len, padded_len; | |
240 | ||
9ce5646a MD |
241 | health_code_update(); |
242 | ||
07b86b52 JD |
243 | DBG("Kernel consumer taking snapshot at pos %lu", consumed_pos); |
244 | ||
245 | ret = kernctl_get_subbuf(stream->wait_fd, &consumed_pos); | |
246 | if (ret < 0) { | |
247 | if (errno != EAGAIN) { | |
248 | PERROR("kernctl_get_subbuf snapshot"); | |
56591bac | 249 | ret = -errno; |
07b86b52 JD |
250 | goto end_unlock; |
251 | } | |
252 | DBG("Kernel consumer get subbuf failed. Skipping it."); | |
253 | consumed_pos += stream->max_sb_size; | |
3daf8c9b | 254 | stream->chan->lost_packets++; |
07b86b52 JD |
255 | continue; |
256 | } | |
257 | ||
258 | ret = kernctl_get_subbuf_size(stream->wait_fd, &len); | |
259 | if (ret < 0) { | |
260 | ERR("Snapshot kernctl_get_subbuf_size"); | |
56591bac | 261 | ret = -errno; |
29decac3 | 262 | goto error_put_subbuf; |
07b86b52 JD |
263 | } |
264 | ||
265 | ret = kernctl_get_padded_subbuf_size(stream->wait_fd, &padded_len); | |
266 | if (ret < 0) { | |
267 | ERR("Snapshot kernctl_get_padded_subbuf_size"); | |
56591bac | 268 | ret = -errno; |
29decac3 | 269 | goto error_put_subbuf; |
07b86b52 JD |
270 | } |
271 | ||
272 | read_len = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, len, | |
309167d2 | 273 | padded_len - len, NULL); |
07b86b52 | 274 | /* |
29decac3 DG |
275 | * We write the padded len in local tracefiles but the data len |
276 | * when using a relay. Display the error but continue processing | |
277 | * to try to release the subbuffer. | |
07b86b52 JD |
278 | */ |
279 | if (relayd_id != (uint64_t) -1ULL) { | |
280 | if (read_len != len) { | |
281 | ERR("Error sending to the relay (ret: %zd != len: %lu)", | |
282 | read_len, len); | |
283 | } | |
284 | } else { | |
285 | if (read_len != padded_len) { | |
286 | ERR("Error writing to tracefile (ret: %zd != len: %lu)", | |
287 | read_len, padded_len); | |
288 | } | |
289 | } | |
290 | ||
291 | ret = kernctl_put_subbuf(stream->wait_fd); | |
292 | if (ret < 0) { | |
293 | ERR("Snapshot kernctl_put_subbuf"); | |
56591bac | 294 | ret = -errno; |
07b86b52 JD |
295 | goto end_unlock; |
296 | } | |
297 | consumed_pos += stream->max_sb_size; | |
298 | } | |
299 | ||
300 | if (relayd_id == (uint64_t) -1ULL) { | |
fdf9986c MD |
301 | if (stream->out_fd >= 0) { |
302 | ret = close(stream->out_fd); | |
303 | if (ret < 0) { | |
304 | PERROR("Kernel consumer snapshot close out_fd"); | |
305 | goto end_unlock; | |
306 | } | |
307 | stream->out_fd = -1; | |
07b86b52 | 308 | } |
07b86b52 JD |
309 | } else { |
310 | close_relayd_stream(stream); | |
311 | stream->net_seq_idx = (uint64_t) -1ULL; | |
312 | } | |
313 | pthread_mutex_unlock(&stream->lock); | |
314 | } | |
315 | ||
316 | /* All good! */ | |
317 | ret = 0; | |
318 | goto end; | |
319 | ||
29decac3 DG |
320 | error_put_subbuf: |
321 | ret = kernctl_put_subbuf(stream->wait_fd); | |
322 | if (ret < 0) { | |
56591bac | 323 | ret = -errno; |
29decac3 DG |
324 | ERR("Snapshot kernctl_put_subbuf error path"); |
325 | } | |
07b86b52 JD |
326 | end_unlock: |
327 | pthread_mutex_unlock(&stream->lock); | |
328 | end: | |
329 | rcu_read_unlock(); | |
330 | return ret; | |
331 | } | |
332 | ||
333 | /* | |
334 | * Read the whole metadata available for a snapshot. | |
335 | * | |
336 | * Returns 0 on success, < 0 on error | |
337 | */ | |
338 | int lttng_kconsumer_snapshot_metadata(uint64_t key, char *path, | |
e2039c7a | 339 | uint64_t relayd_id, struct lttng_consumer_local_data *ctx) |
07b86b52 | 340 | { |
d771f832 DG |
341 | int ret, use_relayd = 0; |
342 | ssize_t ret_read; | |
07b86b52 JD |
343 | struct lttng_consumer_channel *metadata_channel; |
344 | struct lttng_consumer_stream *metadata_stream; | |
d771f832 DG |
345 | |
346 | assert(ctx); | |
07b86b52 JD |
347 | |
348 | DBG("Kernel consumer snapshot metadata with key %" PRIu64 " at path %s", | |
349 | key, path); | |
350 | ||
351 | rcu_read_lock(); | |
352 | ||
353 | metadata_channel = consumer_find_channel(key); | |
354 | if (!metadata_channel) { | |
d771f832 | 355 | ERR("Kernel snapshot metadata not found for key %" PRIu64, key); |
07b86b52 | 356 | ret = -1; |
d771f832 | 357 | goto error; |
07b86b52 JD |
358 | } |
359 | ||
360 | metadata_stream = metadata_channel->metadata_stream; | |
361 | assert(metadata_stream); | |
362 | ||
d771f832 | 363 | /* Flag once that we have a valid relayd for the stream. */ |
e2039c7a | 364 | if (relayd_id != (uint64_t) -1ULL) { |
d771f832 DG |
365 | use_relayd = 1; |
366 | } | |
367 | ||
368 | if (use_relayd) { | |
10a50311 | 369 | ret = consumer_send_relayd_stream(metadata_stream, path); |
e2039c7a | 370 | if (ret < 0) { |
d771f832 | 371 | goto error; |
e2039c7a | 372 | } |
e2039c7a JD |
373 | } else { |
374 | ret = utils_create_stream_file(path, metadata_stream->name, | |
375 | metadata_stream->chan->tracefile_size, | |
376 | metadata_stream->tracefile_count_current, | |
309167d2 | 377 | metadata_stream->uid, metadata_stream->gid, NULL); |
e2039c7a | 378 | if (ret < 0) { |
d771f832 | 379 | goto error; |
e2039c7a JD |
380 | } |
381 | metadata_stream->out_fd = ret; | |
07b86b52 | 382 | } |
07b86b52 | 383 | |
d771f832 | 384 | do { |
9ce5646a MD |
385 | health_code_update(); |
386 | ||
d771f832 DG |
387 | ret_read = lttng_kconsumer_read_subbuffer(metadata_stream, ctx); |
388 | if (ret_read < 0) { | |
56591bac | 389 | if (ret_read != -EAGAIN) { |
6a00837f | 390 | ERR("Kernel snapshot reading metadata subbuffer (ret: %zd)", |
d771f832 DG |
391 | ret_read); |
392 | goto error; | |
07b86b52 | 393 | } |
d771f832 | 394 | /* ret_read is negative at this point so we will exit the loop. */ |
07b86b52 JD |
395 | continue; |
396 | } | |
d771f832 | 397 | } while (ret_read >= 0); |
07b86b52 | 398 | |
d771f832 DG |
399 | if (use_relayd) { |
400 | close_relayd_stream(metadata_stream); | |
401 | metadata_stream->net_seq_idx = (uint64_t) -1ULL; | |
402 | } else { | |
fdf9986c MD |
403 | if (metadata_stream->out_fd >= 0) { |
404 | ret = close(metadata_stream->out_fd); | |
405 | if (ret < 0) { | |
406 | PERROR("Kernel consumer snapshot metadata close out_fd"); | |
407 | /* | |
408 | * Don't go on error here since the snapshot was successful at this | |
409 | * point but somehow the close failed. | |
410 | */ | |
411 | } | |
412 | metadata_stream->out_fd = -1; | |
e2039c7a | 413 | } |
e2039c7a JD |
414 | } |
415 | ||
07b86b52 | 416 | ret = 0; |
d771f832 | 417 | |
cf53a8a6 JD |
418 | cds_list_del(&metadata_stream->send_node); |
419 | consumer_stream_destroy(metadata_stream, NULL); | |
420 | metadata_channel->metadata_stream = NULL; | |
d771f832 | 421 | error: |
07b86b52 JD |
422 | rcu_read_unlock(); |
423 | return ret; | |
424 | } | |
425 | ||
1803a064 MD |
426 | /* |
427 | * Receive command from session daemon and process it. | |
428 | * | |
429 | * Return 1 on success else a negative value or 0. | |
430 | */ | |
3bd1e081 MD |
431 | int lttng_kconsumer_recv_cmd(struct lttng_consumer_local_data *ctx, |
432 | int sock, struct pollfd *consumer_sockpoll) | |
433 | { | |
434 | ssize_t ret; | |
0c759fc9 | 435 | enum lttcomm_return_code ret_code = LTTCOMM_CONSUMERD_SUCCESS; |
3bd1e081 MD |
436 | struct lttcomm_consumer_msg msg; |
437 | ||
9ce5646a MD |
438 | health_code_update(); |
439 | ||
3bd1e081 MD |
440 | ret = lttcomm_recv_unix_sock(sock, &msg, sizeof(msg)); |
441 | if (ret != sizeof(msg)) { | |
1803a064 | 442 | if (ret > 0) { |
c6857fcf | 443 | lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_ERROR_RECV_CMD); |
1803a064 MD |
444 | ret = -1; |
445 | } | |
3bd1e081 MD |
446 | return ret; |
447 | } | |
9ce5646a MD |
448 | |
449 | health_code_update(); | |
450 | ||
84382d49 MD |
451 | /* Deprecated command */ |
452 | assert(msg.cmd_type != LTTNG_CONSUMER_STOP); | |
3bd1e081 | 453 | |
9ce5646a MD |
454 | health_code_update(); |
455 | ||
b0b335c8 MD |
456 | /* relayd needs RCU read-side protection */ |
457 | rcu_read_lock(); | |
458 | ||
3bd1e081 | 459 | switch (msg.cmd_type) { |
00e2e675 DG |
460 | case LTTNG_CONSUMER_ADD_RELAYD_SOCKET: |
461 | { | |
f50f23d9 | 462 | /* Session daemon status message are handled in the following call. */ |
7735ef9e DG |
463 | ret = consumer_add_relayd_socket(msg.u.relayd_sock.net_index, |
464 | msg.u.relayd_sock.type, ctx, sock, consumer_sockpoll, | |
d3e2ba59 JD |
465 | &msg.u.relayd_sock.sock, msg.u.relayd_sock.session_id, |
466 | msg.u.relayd_sock.relayd_session_id); | |
00e2e675 DG |
467 | goto end_nosignal; |
468 | } | |
3bd1e081 MD |
469 | case LTTNG_CONSUMER_ADD_CHANNEL: |
470 | { | |
471 | struct lttng_consumer_channel *new_channel; | |
e43c41c5 | 472 | int ret_recv; |
3bd1e081 | 473 | |
9ce5646a MD |
474 | health_code_update(); |
475 | ||
f50f23d9 DG |
476 | /* First send a status message before receiving the fds. */ |
477 | ret = consumer_send_status_msg(sock, ret_code); | |
478 | if (ret < 0) { | |
479 | /* Somehow, the session daemon is not responding anymore. */ | |
1803a064 | 480 | goto error_fatal; |
f50f23d9 | 481 | } |
9ce5646a MD |
482 | |
483 | health_code_update(); | |
484 | ||
d88aee68 | 485 | DBG("consumer_add_channel %" PRIu64, msg.u.channel.channel_key); |
3bd1e081 | 486 | new_channel = consumer_allocate_channel(msg.u.channel.channel_key, |
ffe60014 DG |
487 | msg.u.channel.session_id, msg.u.channel.pathname, |
488 | msg.u.channel.name, msg.u.channel.uid, msg.u.channel.gid, | |
1624d5b7 JD |
489 | msg.u.channel.relayd_id, msg.u.channel.output, |
490 | msg.u.channel.tracefile_size, | |
1950109e | 491 | msg.u.channel.tracefile_count, 0, |
ecc48a90 | 492 | msg.u.channel.monitor, |
d7ba1388 | 493 | msg.u.channel.live_timer_interval, |
3d071855 | 494 | NULL, NULL); |
3bd1e081 | 495 | if (new_channel == NULL) { |
f73fabfd | 496 | lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_OUTFD_ERROR); |
3bd1e081 MD |
497 | goto end_nosignal; |
498 | } | |
ffe60014 | 499 | new_channel->nb_init_stream_left = msg.u.channel.nb_init_streams; |
95a1109b JD |
500 | switch (msg.u.channel.output) { |
501 | case LTTNG_EVENT_SPLICE: | |
502 | new_channel->output = CONSUMER_CHANNEL_SPLICE; | |
503 | break; | |
504 | case LTTNG_EVENT_MMAP: | |
505 | new_channel->output = CONSUMER_CHANNEL_MMAP; | |
506 | break; | |
507 | default: | |
508 | ERR("Channel output unknown %d", msg.u.channel.output); | |
509 | goto end_nosignal; | |
510 | } | |
ffe60014 DG |
511 | |
512 | /* Translate and save channel type. */ | |
513 | switch (msg.u.channel.type) { | |
514 | case CONSUMER_CHANNEL_TYPE_DATA: | |
515 | case CONSUMER_CHANNEL_TYPE_METADATA: | |
516 | new_channel->type = msg.u.channel.type; | |
517 | break; | |
518 | default: | |
519 | assert(0); | |
520 | goto end_nosignal; | |
521 | }; | |
522 | ||
9ce5646a MD |
523 | health_code_update(); |
524 | ||
3bd1e081 | 525 | if (ctx->on_recv_channel != NULL) { |
e43c41c5 JD |
526 | ret_recv = ctx->on_recv_channel(new_channel); |
527 | if (ret_recv == 0) { | |
528 | ret = consumer_add_channel(new_channel, ctx); | |
529 | } else if (ret_recv < 0) { | |
3bd1e081 MD |
530 | goto end_nosignal; |
531 | } | |
532 | } else { | |
e43c41c5 | 533 | ret = consumer_add_channel(new_channel, ctx); |
3bd1e081 | 534 | } |
94d49140 JD |
535 | if (CONSUMER_CHANNEL_TYPE_DATA) { |
536 | consumer_timer_live_start(new_channel, | |
537 | msg.u.channel.live_timer_interval); | |
538 | } | |
e43c41c5 | 539 | |
9ce5646a MD |
540 | health_code_update(); |
541 | ||
e43c41c5 | 542 | /* If we received an error in add_channel, we need to report it. */ |
821fffb2 | 543 | if (ret < 0) { |
1803a064 MD |
544 | ret = consumer_send_status_msg(sock, ret); |
545 | if (ret < 0) { | |
546 | goto error_fatal; | |
547 | } | |
e43c41c5 JD |
548 | goto end_nosignal; |
549 | } | |
550 | ||
3bd1e081 MD |
551 | goto end_nosignal; |
552 | } | |
553 | case LTTNG_CONSUMER_ADD_STREAM: | |
554 | { | |
dae10966 DG |
555 | int fd; |
556 | struct lttng_pipe *stream_pipe; | |
00e2e675 | 557 | struct lttng_consumer_stream *new_stream; |
ffe60014 | 558 | struct lttng_consumer_channel *channel; |
c80048c6 | 559 | int alloc_ret = 0; |
3bd1e081 | 560 | |
ffe60014 DG |
561 | /* |
562 | * Get stream's channel reference. Needed when adding the stream to the | |
563 | * global hash table. | |
564 | */ | |
565 | channel = consumer_find_channel(msg.u.stream.channel_key); | |
566 | if (!channel) { | |
567 | /* | |
568 | * We could not find the channel. Can happen if cpu hotplug | |
569 | * happens while tearing down. | |
570 | */ | |
d88aee68 | 571 | ERR("Unable to find channel key %" PRIu64, msg.u.stream.channel_key); |
e462382a | 572 | ret_code = LTTCOMM_CONSUMERD_CHAN_NOT_FOUND; |
ffe60014 DG |
573 | } |
574 | ||
9ce5646a MD |
575 | health_code_update(); |
576 | ||
f50f23d9 DG |
577 | /* First send a status message before receiving the fds. */ |
578 | ret = consumer_send_status_msg(sock, ret_code); | |
1803a064 | 579 | if (ret < 0) { |
d771f832 | 580 | /* Somehow, the session daemon is not responding anymore. */ |
1803a064 MD |
581 | goto error_fatal; |
582 | } | |
9ce5646a MD |
583 | |
584 | health_code_update(); | |
585 | ||
0c759fc9 | 586 | if (ret_code != LTTCOMM_CONSUMERD_SUCCESS) { |
d771f832 | 587 | /* Channel was not found. */ |
f50f23d9 DG |
588 | goto end_nosignal; |
589 | } | |
590 | ||
d771f832 | 591 | /* Blocking call */ |
9ce5646a MD |
592 | health_poll_entry(); |
593 | ret = lttng_consumer_poll_socket(consumer_sockpoll); | |
594 | health_poll_exit(); | |
84382d49 MD |
595 | if (ret) { |
596 | goto error_fatal; | |
3bd1e081 | 597 | } |
00e2e675 | 598 | |
9ce5646a MD |
599 | health_code_update(); |
600 | ||
00e2e675 | 601 | /* Get stream file descriptor from socket */ |
f2fc6720 MD |
602 | ret = lttcomm_recv_fds_unix_sock(sock, &fd, 1); |
603 | if (ret != sizeof(fd)) { | |
f73fabfd | 604 | lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_ERROR_RECV_FD); |
3f8e211f | 605 | rcu_read_unlock(); |
3bd1e081 MD |
606 | return ret; |
607 | } | |
3bd1e081 | 608 | |
9ce5646a MD |
609 | health_code_update(); |
610 | ||
f50f23d9 DG |
611 | /* |
612 | * Send status code to session daemon only if the recv works. If the | |
613 | * above recv() failed, the session daemon is notified through the | |
614 | * error socket and the teardown is eventually done. | |
615 | */ | |
616 | ret = consumer_send_status_msg(sock, ret_code); | |
617 | if (ret < 0) { | |
618 | /* Somehow, the session daemon is not responding anymore. */ | |
619 | goto end_nosignal; | |
620 | } | |
621 | ||
9ce5646a MD |
622 | health_code_update(); |
623 | ||
ffe60014 DG |
624 | new_stream = consumer_allocate_stream(channel->key, |
625 | fd, | |
626 | LTTNG_CONSUMER_ACTIVE_STREAM, | |
627 | channel->name, | |
628 | channel->uid, | |
629 | channel->gid, | |
630 | channel->relayd_id, | |
631 | channel->session_id, | |
632 | msg.u.stream.cpu, | |
633 | &alloc_ret, | |
4891ece8 DG |
634 | channel->type, |
635 | channel->monitor); | |
3bd1e081 | 636 | if (new_stream == NULL) { |
c80048c6 MD |
637 | switch (alloc_ret) { |
638 | case -ENOMEM: | |
639 | case -EINVAL: | |
640 | default: | |
641 | lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_OUTFD_ERROR); | |
642 | break; | |
c80048c6 | 643 | } |
3f8e211f | 644 | goto end_nosignal; |
3bd1e081 | 645 | } |
d771f832 | 646 | |
ffe60014 DG |
647 | new_stream->chan = channel; |
648 | new_stream->wait_fd = fd; | |
07b86b52 JD |
649 | switch (channel->output) { |
650 | case CONSUMER_CHANNEL_SPLICE: | |
651 | new_stream->output = LTTNG_EVENT_SPLICE; | |
a2361a61 JD |
652 | ret = utils_create_pipe(new_stream->splice_pipe); |
653 | if (ret < 0) { | |
654 | goto end_nosignal; | |
655 | } | |
07b86b52 JD |
656 | break; |
657 | case CONSUMER_CHANNEL_MMAP: | |
658 | new_stream->output = LTTNG_EVENT_MMAP; | |
659 | break; | |
660 | default: | |
661 | ERR("Stream output unknown %d", channel->output); | |
662 | goto end_nosignal; | |
663 | } | |
00e2e675 | 664 | |
a0c83db9 DG |
665 | /* |
666 | * We've just assigned the channel to the stream so increment the | |
07b86b52 JD |
667 | * refcount right now. We don't need to increment the refcount for |
668 | * streams in no monitor because we handle manually the cleanup of | |
669 | * those. It is very important to make sure there is NO prior | |
670 | * consumer_del_stream() calls or else the refcount will be unbalanced. | |
a0c83db9 | 671 | */ |
07b86b52 JD |
672 | if (channel->monitor) { |
673 | uatomic_inc(&new_stream->chan->refcount); | |
674 | } | |
9d9353f9 | 675 | |
fb3a43a9 DG |
676 | /* |
677 | * The buffer flush is done on the session daemon side for the kernel | |
678 | * so no need for the stream "hangup_flush_done" variable to be | |
679 | * tracked. This is important for a kernel stream since we don't rely | |
680 | * on the flush state of the stream to read data. It's not the case for | |
681 | * user space tracing. | |
682 | */ | |
683 | new_stream->hangup_flush_done = 0; | |
684 | ||
9ce5646a MD |
685 | health_code_update(); |
686 | ||
633d0084 DG |
687 | if (ctx->on_recv_stream) { |
688 | ret = ctx->on_recv_stream(new_stream); | |
689 | if (ret < 0) { | |
d771f832 | 690 | consumer_stream_free(new_stream); |
633d0084 | 691 | goto end_nosignal; |
fb3a43a9 | 692 | } |
633d0084 | 693 | } |
fb3a43a9 | 694 | |
9ce5646a MD |
695 | health_code_update(); |
696 | ||
07b86b52 JD |
697 | if (new_stream->metadata_flag) { |
698 | channel->metadata_stream = new_stream; | |
699 | } | |
700 | ||
2bba9e53 DG |
701 | /* Do not monitor this stream. */ |
702 | if (!channel->monitor) { | |
5eecee74 | 703 | DBG("Kernel consumer add stream %s in no monitor mode with " |
6dc3064a | 704 | "relayd id %" PRIu64, new_stream->name, |
5eecee74 | 705 | new_stream->net_seq_idx); |
10a50311 | 706 | cds_list_add(&new_stream->send_node, &channel->streams.head); |
6dc3064a DG |
707 | break; |
708 | } | |
709 | ||
e1b71bdc DG |
710 | /* Send stream to relayd if the stream has an ID. */ |
711 | if (new_stream->net_seq_idx != (uint64_t) -1ULL) { | |
194ee077 DG |
712 | ret = consumer_send_relayd_stream(new_stream, |
713 | new_stream->chan->pathname); | |
e1b71bdc DG |
714 | if (ret < 0) { |
715 | consumer_stream_free(new_stream); | |
716 | goto end_nosignal; | |
717 | } | |
7881b1c4 MD |
718 | |
719 | /* | |
720 | * If adding an extra stream to an already | |
721 | * existing channel (e.g. cpu hotplug), we need | |
722 | * to send the "streams_sent" command to relayd. | |
723 | */ | |
724 | if (channel->streams_sent_to_relayd) { | |
725 | ret = consumer_send_relayd_streams_sent( | |
726 | new_stream->net_seq_idx); | |
727 | if (ret < 0) { | |
728 | goto end_nosignal; | |
729 | } | |
730 | } | |
e2039c7a JD |
731 | } |
732 | ||
50f8ae69 | 733 | /* Get the right pipe where the stream will be sent. */ |
633d0084 | 734 | if (new_stream->metadata_flag) { |
5ab66908 MD |
735 | ret = consumer_add_metadata_stream(new_stream); |
736 | if (ret) { | |
737 | ERR("Consumer add metadata stream %" PRIu64 " failed. Continuing", | |
738 | new_stream->key); | |
739 | consumer_stream_free(new_stream); | |
740 | goto end_nosignal; | |
741 | } | |
dae10966 | 742 | stream_pipe = ctx->consumer_metadata_pipe; |
3bd1e081 | 743 | } else { |
5ab66908 MD |
744 | ret = consumer_add_data_stream(new_stream); |
745 | if (ret) { | |
746 | ERR("Consumer add stream %" PRIu64 " failed. Continuing", | |
747 | new_stream->key); | |
748 | consumer_stream_free(new_stream); | |
749 | goto end_nosignal; | |
750 | } | |
dae10966 | 751 | stream_pipe = ctx->consumer_data_pipe; |
50f8ae69 DG |
752 | } |
753 | ||
5ab66908 MD |
754 | /* Vitible to other threads */ |
755 | new_stream->globally_visible = 1; | |
756 | ||
9ce5646a MD |
757 | health_code_update(); |
758 | ||
dae10966 | 759 | ret = lttng_pipe_write(stream_pipe, &new_stream, sizeof(new_stream)); |
50f8ae69 | 760 | if (ret < 0) { |
dae10966 | 761 | ERR("Consumer write %s stream to pipe %d", |
50f8ae69 | 762 | new_stream->metadata_flag ? "metadata" : "data", |
dae10966 | 763 | lttng_pipe_get_writefd(stream_pipe)); |
5ab66908 MD |
764 | if (new_stream->metadata_flag) { |
765 | consumer_del_stream_for_metadata(new_stream); | |
766 | } else { | |
767 | consumer_del_stream_for_data(new_stream); | |
768 | } | |
50f8ae69 | 769 | goto end_nosignal; |
3bd1e081 | 770 | } |
00e2e675 | 771 | |
50f8ae69 | 772 | DBG("Kernel consumer ADD_STREAM %s (fd: %d) with relayd id %" PRIu64, |
ffe60014 | 773 | new_stream->name, fd, new_stream->relayd_stream_id); |
3bd1e081 MD |
774 | break; |
775 | } | |
a4baae1b JD |
776 | case LTTNG_CONSUMER_STREAMS_SENT: |
777 | { | |
778 | struct lttng_consumer_channel *channel; | |
779 | ||
780 | /* | |
781 | * Get stream's channel reference. Needed when adding the stream to the | |
782 | * global hash table. | |
783 | */ | |
784 | channel = consumer_find_channel(msg.u.sent_streams.channel_key); | |
785 | if (!channel) { | |
786 | /* | |
787 | * We could not find the channel. Can happen if cpu hotplug | |
788 | * happens while tearing down. | |
789 | */ | |
790 | ERR("Unable to find channel key %" PRIu64, | |
791 | msg.u.sent_streams.channel_key); | |
e462382a | 792 | ret_code = LTTCOMM_CONSUMERD_CHAN_NOT_FOUND; |
a4baae1b JD |
793 | } |
794 | ||
795 | health_code_update(); | |
796 | ||
797 | /* | |
798 | * Send status code to session daemon. | |
799 | */ | |
800 | ret = consumer_send_status_msg(sock, ret_code); | |
f261ad0a | 801 | if (ret < 0 || ret_code != LTTCOMM_CONSUMERD_SUCCESS) { |
a4baae1b JD |
802 | /* Somehow, the session daemon is not responding anymore. */ |
803 | goto end_nosignal; | |
804 | } | |
805 | ||
806 | health_code_update(); | |
807 | ||
808 | /* | |
809 | * We should not send this message if we don't monitor the | |
810 | * streams in this channel. | |
811 | */ | |
812 | if (!channel->monitor) { | |
813 | break; | |
814 | } | |
815 | ||
816 | health_code_update(); | |
817 | /* Send stream to relayd if the stream has an ID. */ | |
818 | if (msg.u.sent_streams.net_seq_idx != (uint64_t) -1ULL) { | |
819 | ret = consumer_send_relayd_streams_sent( | |
820 | msg.u.sent_streams.net_seq_idx); | |
821 | if (ret < 0) { | |
822 | goto end_nosignal; | |
823 | } | |
7881b1c4 | 824 | channel->streams_sent_to_relayd = true; |
a4baae1b JD |
825 | } |
826 | break; | |
827 | } | |
3bd1e081 MD |
828 | case LTTNG_CONSUMER_UPDATE_STREAM: |
829 | { | |
3f8e211f DG |
830 | rcu_read_unlock(); |
831 | return -ENOSYS; | |
832 | } | |
833 | case LTTNG_CONSUMER_DESTROY_RELAYD: | |
834 | { | |
a6ba4fe1 | 835 | uint64_t index = msg.u.destroy_relayd.net_seq_idx; |
3f8e211f DG |
836 | struct consumer_relayd_sock_pair *relayd; |
837 | ||
a6ba4fe1 | 838 | DBG("Kernel consumer destroying relayd %" PRIu64, index); |
3f8e211f DG |
839 | |
840 | /* Get relayd reference if exists. */ | |
a6ba4fe1 | 841 | relayd = consumer_find_relayd(index); |
3f8e211f | 842 | if (relayd == NULL) { |
3448e266 | 843 | DBG("Unable to find relayd %" PRIu64, index); |
e462382a | 844 | ret_code = LTTCOMM_CONSUMERD_RELAYD_FAIL; |
3bd1e081 | 845 | } |
3f8e211f | 846 | |
a6ba4fe1 DG |
847 | /* |
848 | * Each relayd socket pair has a refcount of stream attached to it | |
849 | * which tells if the relayd is still active or not depending on the | |
850 | * refcount value. | |
851 | * | |
852 | * This will set the destroy flag of the relayd object and destroy it | |
853 | * if the refcount reaches zero when called. | |
854 | * | |
855 | * The destroy can happen either here or when a stream fd hangs up. | |
856 | */ | |
f50f23d9 DG |
857 | if (relayd) { |
858 | consumer_flag_relayd_for_destroy(relayd); | |
859 | } | |
860 | ||
9ce5646a MD |
861 | health_code_update(); |
862 | ||
f50f23d9 DG |
863 | ret = consumer_send_status_msg(sock, ret_code); |
864 | if (ret < 0) { | |
865 | /* Somehow, the session daemon is not responding anymore. */ | |
1803a064 | 866 | goto error_fatal; |
f50f23d9 | 867 | } |
3f8e211f | 868 | |
3f8e211f | 869 | goto end_nosignal; |
3bd1e081 | 870 | } |
6d805429 | 871 | case LTTNG_CONSUMER_DATA_PENDING: |
53632229 | 872 | { |
c8f59ee5 | 873 | int32_t ret; |
6d805429 | 874 | uint64_t id = msg.u.data_pending.session_id; |
c8f59ee5 | 875 | |
6d805429 | 876 | DBG("Kernel consumer data pending command for id %" PRIu64, id); |
c8f59ee5 | 877 | |
6d805429 | 878 | ret = consumer_data_pending(id); |
c8f59ee5 | 879 | |
9ce5646a MD |
880 | health_code_update(); |
881 | ||
c8f59ee5 DG |
882 | /* Send back returned value to session daemon */ |
883 | ret = lttcomm_send_unix_sock(sock, &ret, sizeof(ret)); | |
884 | if (ret < 0) { | |
6d805429 | 885 | PERROR("send data pending ret code"); |
1803a064 | 886 | goto error_fatal; |
c8f59ee5 | 887 | } |
f50f23d9 DG |
888 | |
889 | /* | |
890 | * No need to send back a status message since the data pending | |
891 | * returned value is the response. | |
892 | */ | |
c8f59ee5 | 893 | break; |
53632229 | 894 | } |
6dc3064a DG |
895 | case LTTNG_CONSUMER_SNAPSHOT_CHANNEL: |
896 | { | |
07b86b52 JD |
897 | if (msg.u.snapshot_channel.metadata == 1) { |
898 | ret = lttng_kconsumer_snapshot_metadata(msg.u.snapshot_channel.key, | |
e2039c7a JD |
899 | msg.u.snapshot_channel.pathname, |
900 | msg.u.snapshot_channel.relayd_id, ctx); | |
07b86b52 JD |
901 | if (ret < 0) { |
902 | ERR("Snapshot metadata failed"); | |
e462382a | 903 | ret_code = LTTCOMM_CONSUMERD_ERROR_METADATA; |
07b86b52 JD |
904 | } |
905 | } else { | |
906 | ret = lttng_kconsumer_snapshot_channel(msg.u.snapshot_channel.key, | |
907 | msg.u.snapshot_channel.pathname, | |
5c786ded | 908 | msg.u.snapshot_channel.relayd_id, |
d07ceecd | 909 | msg.u.snapshot_channel.nb_packets_per_stream, |
5c786ded | 910 | ctx); |
07b86b52 JD |
911 | if (ret < 0) { |
912 | ERR("Snapshot channel failed"); | |
e462382a | 913 | ret_code = LTTCOMM_CONSUMERD_CHAN_NOT_FOUND; |
07b86b52 JD |
914 | } |
915 | } | |
916 | ||
9ce5646a MD |
917 | health_code_update(); |
918 | ||
6dc3064a DG |
919 | ret = consumer_send_status_msg(sock, ret_code); |
920 | if (ret < 0) { | |
921 | /* Somehow, the session daemon is not responding anymore. */ | |
922 | goto end_nosignal; | |
923 | } | |
924 | break; | |
925 | } | |
07b86b52 JD |
926 | case LTTNG_CONSUMER_DESTROY_CHANNEL: |
927 | { | |
928 | uint64_t key = msg.u.destroy_channel.key; | |
929 | struct lttng_consumer_channel *channel; | |
930 | ||
931 | channel = consumer_find_channel(key); | |
932 | if (!channel) { | |
933 | ERR("Kernel consumer destroy channel %" PRIu64 " not found", key); | |
e462382a | 934 | ret_code = LTTCOMM_CONSUMERD_CHAN_NOT_FOUND; |
07b86b52 JD |
935 | } |
936 | ||
9ce5646a MD |
937 | health_code_update(); |
938 | ||
07b86b52 JD |
939 | ret = consumer_send_status_msg(sock, ret_code); |
940 | if (ret < 0) { | |
941 | /* Somehow, the session daemon is not responding anymore. */ | |
942 | goto end_nosignal; | |
943 | } | |
944 | ||
9ce5646a MD |
945 | health_code_update(); |
946 | ||
15dc512a DG |
947 | /* Stop right now if no channel was found. */ |
948 | if (!channel) { | |
949 | goto end_nosignal; | |
950 | } | |
951 | ||
07b86b52 JD |
952 | /* |
953 | * This command should ONLY be issued for channel with streams set in | |
954 | * no monitor mode. | |
955 | */ | |
956 | assert(!channel->monitor); | |
957 | ||
958 | /* | |
959 | * The refcount should ALWAYS be 0 in the case of a channel in no | |
960 | * monitor mode. | |
961 | */ | |
962 | assert(!uatomic_sub_return(&channel->refcount, 1)); | |
963 | ||
964 | consumer_del_channel(channel); | |
965 | ||
966 | goto end_nosignal; | |
967 | } | |
fb83fe64 JD |
968 | case LTTNG_CONSUMER_DISCARDED_EVENTS: |
969 | { | |
970 | uint64_t ret; | |
971 | struct lttng_consumer_channel *channel; | |
972 | uint64_t id = msg.u.discarded_events.session_id; | |
973 | uint64_t key = msg.u.discarded_events.channel_key; | |
974 | ||
bf181b05 MD |
975 | DBG("Kernel consumer discarded events command for session id %" |
976 | PRIu64 ", channel key %" PRIu64, id, key); | |
977 | ||
fb83fe64 JD |
978 | channel = consumer_find_channel(key); |
979 | if (!channel) { | |
980 | ERR("Kernel consumer discarded events channel %" | |
981 | PRIu64 " not found", key); | |
bf181b05 MD |
982 | ret = 0; |
983 | } else { | |
984 | ret = channel->discarded_events; | |
fb83fe64 JD |
985 | } |
986 | ||
fb83fe64 JD |
987 | health_code_update(); |
988 | ||
989 | /* Send back returned value to session daemon */ | |
990 | ret = lttcomm_send_unix_sock(sock, &ret, sizeof(ret)); | |
991 | if (ret < 0) { | |
992 | PERROR("send discarded events"); | |
993 | goto error_fatal; | |
994 | } | |
995 | ||
996 | break; | |
997 | } | |
998 | case LTTNG_CONSUMER_LOST_PACKETS: | |
999 | { | |
1000 | uint64_t ret; | |
1001 | struct lttng_consumer_channel *channel; | |
1002 | uint64_t id = msg.u.lost_packets.session_id; | |
1003 | uint64_t key = msg.u.lost_packets.channel_key; | |
1004 | ||
bf181b05 MD |
1005 | DBG("Kernel consumer lost packets command for session id %" |
1006 | PRIu64 ", channel key %" PRIu64, id, key); | |
1007 | ||
fb83fe64 JD |
1008 | channel = consumer_find_channel(key); |
1009 | if (!channel) { | |
1010 | ERR("Kernel consumer lost packets channel %" | |
1011 | PRIu64 " not found", key); | |
bf181b05 MD |
1012 | ret = 0; |
1013 | } else { | |
1014 | ret = channel->lost_packets; | |
fb83fe64 JD |
1015 | } |
1016 | ||
fb83fe64 JD |
1017 | health_code_update(); |
1018 | ||
1019 | /* Send back returned value to session daemon */ | |
1020 | ret = lttcomm_send_unix_sock(sock, &ret, sizeof(ret)); | |
1021 | if (ret < 0) { | |
1022 | PERROR("send lost packets"); | |
1023 | goto error_fatal; | |
1024 | } | |
1025 | ||
1026 | break; | |
1027 | } | |
3bd1e081 | 1028 | default: |
3f8e211f | 1029 | goto end_nosignal; |
3bd1e081 | 1030 | } |
3f8e211f | 1031 | |
3bd1e081 | 1032 | end_nosignal: |
b0b335c8 | 1033 | rcu_read_unlock(); |
4cbc1a04 DG |
1034 | |
1035 | /* | |
1036 | * Return 1 to indicate success since the 0 value can be a socket | |
1037 | * shutdown during the recv() or send() call. | |
1038 | */ | |
9ce5646a | 1039 | health_code_update(); |
4cbc1a04 | 1040 | return 1; |
1803a064 MD |
1041 | |
1042 | error_fatal: | |
1043 | rcu_read_unlock(); | |
1044 | /* This will issue a consumer stop. */ | |
1045 | return -1; | |
3bd1e081 | 1046 | } |
d41f73b7 | 1047 | |
309167d2 JD |
1048 | /* |
1049 | * Populate index values of a kernel stream. Values are set in big endian order. | |
1050 | * | |
1051 | * Return 0 on success or else a negative value. | |
1052 | */ | |
50adc264 | 1053 | static int get_index_values(struct ctf_packet_index *index, int infd) |
309167d2 JD |
1054 | { |
1055 | int ret; | |
1056 | ||
1057 | ret = kernctl_get_timestamp_begin(infd, &index->timestamp_begin); | |
1058 | if (ret < 0) { | |
1059 | PERROR("kernctl_get_timestamp_begin"); | |
1060 | goto error; | |
1061 | } | |
1062 | index->timestamp_begin = htobe64(index->timestamp_begin); | |
1063 | ||
1064 | ret = kernctl_get_timestamp_end(infd, &index->timestamp_end); | |
1065 | if (ret < 0) { | |
1066 | PERROR("kernctl_get_timestamp_end"); | |
1067 | goto error; | |
1068 | } | |
1069 | index->timestamp_end = htobe64(index->timestamp_end); | |
1070 | ||
1071 | ret = kernctl_get_events_discarded(infd, &index->events_discarded); | |
1072 | if (ret < 0) { | |
1073 | PERROR("kernctl_get_events_discarded"); | |
1074 | goto error; | |
1075 | } | |
1076 | index->events_discarded = htobe64(index->events_discarded); | |
1077 | ||
1078 | ret = kernctl_get_content_size(infd, &index->content_size); | |
1079 | if (ret < 0) { | |
1080 | PERROR("kernctl_get_content_size"); | |
1081 | goto error; | |
1082 | } | |
1083 | index->content_size = htobe64(index->content_size); | |
1084 | ||
1085 | ret = kernctl_get_packet_size(infd, &index->packet_size); | |
1086 | if (ret < 0) { | |
1087 | PERROR("kernctl_get_packet_size"); | |
1088 | goto error; | |
1089 | } | |
1090 | index->packet_size = htobe64(index->packet_size); | |
1091 | ||
1092 | ret = kernctl_get_stream_id(infd, &index->stream_id); | |
1093 | if (ret < 0) { | |
1094 | PERROR("kernctl_get_stream_id"); | |
1095 | goto error; | |
1096 | } | |
1097 | index->stream_id = htobe64(index->stream_id); | |
1098 | ||
234cd636 JD |
1099 | ret = kernctl_get_instance_id(infd, &index->stream_instance_id); |
1100 | if (ret < 0) { | |
912a3957 MD |
1101 | if (ret == -ENOTTY) { |
1102 | /* Command not implemented by lttng-modules. */ | |
1103 | index->stream_instance_id = -1ULL; | |
1104 | ret = 0; | |
1105 | } else { | |
1106 | PERROR("kernctl_get_instance_id"); | |
1107 | goto error; | |
1108 | } | |
234cd636 JD |
1109 | } |
1110 | index->stream_instance_id = htobe64(index->stream_instance_id); | |
1111 | ||
1112 | ret = kernctl_get_sequence_number(infd, &index->packet_seq_num); | |
1113 | if (ret < 0) { | |
912a3957 MD |
1114 | if (ret == -ENOTTY) { |
1115 | /* Command not implemented by lttng-modules. */ | |
1116 | index->packet_seq_num = -1ULL; | |
1117 | ret = 0; | |
1118 | } else { | |
1119 | PERROR("kernctl_get_sequence_number"); | |
1120 | goto error; | |
1121 | } | |
234cd636 JD |
1122 | } |
1123 | index->packet_seq_num = htobe64(index->packet_seq_num); | |
1124 | ||
309167d2 JD |
1125 | error: |
1126 | return ret; | |
1127 | } | |
94d49140 JD |
1128 | /* |
1129 | * Sync metadata meaning request them to the session daemon and snapshot to the | |
1130 | * metadata thread can consumer them. | |
1131 | * | |
1132 | * Metadata stream lock MUST be acquired. | |
1133 | * | |
1134 | * Return 0 if new metadatda is available, EAGAIN if the metadata stream | |
1135 | * is empty or a negative value on error. | |
1136 | */ | |
1137 | int lttng_kconsumer_sync_metadata(struct lttng_consumer_stream *metadata) | |
1138 | { | |
1139 | int ret; | |
1140 | ||
1141 | assert(metadata); | |
1142 | ||
1143 | ret = kernctl_buffer_flush(metadata->wait_fd); | |
1144 | if (ret < 0) { | |
1145 | ERR("Failed to flush kernel stream"); | |
1146 | goto end; | |
1147 | } | |
1148 | ||
1149 | ret = kernctl_snapshot(metadata->wait_fd); | |
1150 | if (ret < 0) { | |
1151 | if (errno != EAGAIN) { | |
1152 | ERR("Sync metadata, taking kernel snapshot failed."); | |
1153 | goto end; | |
1154 | } | |
1155 | DBG("Sync metadata, no new kernel metadata"); | |
1156 | /* No new metadata, exit. */ | |
1157 | ret = ENODATA; | |
1158 | goto end; | |
1159 | } | |
1160 | ||
1161 | end: | |
1162 | return ret; | |
1163 | } | |
309167d2 | 1164 | |
fb83fe64 JD |
1165 | static |
1166 | int update_stream_stats(struct lttng_consumer_stream *stream) | |
1167 | { | |
1168 | int ret; | |
1169 | uint64_t seq, discarded; | |
1170 | ||
1171 | ret = kernctl_get_sequence_number(stream->wait_fd, &seq); | |
1172 | if (ret < 0) { | |
912a3957 MD |
1173 | if (ret == -ENOTTY) { |
1174 | /* Command not implemented by lttng-modules. */ | |
1175 | seq = -1ULL; | |
1176 | ret = 0; | |
1177 | } else { | |
1178 | PERROR("kernctl_get_sequence_number"); | |
1179 | goto end; | |
1180 | } | |
fb83fe64 JD |
1181 | } |
1182 | ||
1183 | /* | |
1184 | * Start the sequence when we extract the first packet in case we don't | |
1185 | * start at 0 (for example if a consumer is not connected to the | |
1186 | * session immediately after the beginning). | |
1187 | */ | |
1188 | if (stream->last_sequence_number == -1ULL) { | |
1189 | stream->last_sequence_number = seq; | |
1190 | } else if (seq > stream->last_sequence_number) { | |
1191 | stream->chan->lost_packets += seq - | |
1192 | stream->last_sequence_number - 1; | |
1193 | } else { | |
1194 | /* seq <= last_sequence_number */ | |
1195 | ERR("Sequence number inconsistent : prev = %" PRIu64 | |
1196 | ", current = %" PRIu64, | |
1197 | stream->last_sequence_number, seq); | |
1198 | ret = -1; | |
1199 | goto end; | |
1200 | } | |
1201 | stream->last_sequence_number = seq; | |
1202 | ||
1203 | ret = kernctl_get_events_discarded(stream->wait_fd, &discarded); | |
1204 | if (ret < 0) { | |
1205 | PERROR("kernctl_get_events_discarded"); | |
1206 | goto end; | |
1207 | } | |
1208 | if (discarded < stream->last_discarded_events) { | |
1209 | /* | |
fae1e3cc MJ |
1210 | * Overflow has occurred. We assume only one wrap-around |
1211 | * has occurred. | |
fb83fe64 JD |
1212 | */ |
1213 | stream->chan->discarded_events += (1ULL << (CAA_BITS_PER_LONG - 1)) - | |
1214 | stream->last_discarded_events + discarded; | |
1215 | } else { | |
1216 | stream->chan->discarded_events += discarded - | |
1217 | stream->last_discarded_events; | |
1218 | } | |
1219 | stream->last_discarded_events = discarded; | |
1220 | ret = 0; | |
1221 | ||
1222 | end: | |
1223 | return ret; | |
1224 | } | |
1225 | ||
93ec662e JD |
1226 | /* |
1227 | * Check if the local version of the metadata stream matches with the version | |
1228 | * of the metadata stream in the kernel. If it was updated, set the reset flag | |
1229 | * on the stream. | |
1230 | */ | |
1231 | static | |
1232 | int metadata_stream_check_version(int infd, struct lttng_consumer_stream *stream) | |
1233 | { | |
1234 | int ret; | |
1235 | uint64_t cur_version; | |
1236 | ||
1237 | ret = kernctl_get_metadata_version(infd, &cur_version); | |
1238 | if (ret < 0) { | |
912a3957 MD |
1239 | if (ret == -ENOTTY) { |
1240 | /* | |
1241 | * LTTng-modules does not implement this | |
1242 | * command. | |
1243 | */ | |
1244 | ret = 0; | |
1245 | goto end; | |
1246 | } | |
93ec662e JD |
1247 | ERR("Failed to get the metadata version"); |
1248 | goto end; | |
1249 | } | |
1250 | ||
1251 | if (stream->metadata_version == cur_version) { | |
1252 | ret = 0; | |
1253 | goto end; | |
1254 | } | |
1255 | ||
1256 | DBG("New metadata version detected"); | |
1257 | stream->metadata_version = cur_version; | |
1258 | stream->reset_metadata_flag = 1; | |
1259 | ret = 0; | |
1260 | ||
1261 | end: | |
1262 | return ret; | |
1263 | } | |
1264 | ||
d41f73b7 MD |
1265 | /* |
1266 | * Consume data on a file descriptor and write it on a trace file. | |
1267 | */ | |
4078b776 | 1268 | ssize_t lttng_kconsumer_read_subbuffer(struct lttng_consumer_stream *stream, |
d41f73b7 MD |
1269 | struct lttng_consumer_local_data *ctx) |
1270 | { | |
1d4dfdef | 1271 | unsigned long len, subbuf_size, padding; |
1c20f0e2 | 1272 | int err, write_index = 1; |
4078b776 | 1273 | ssize_t ret = 0; |
d41f73b7 | 1274 | int infd = stream->wait_fd; |
50adc264 | 1275 | struct ctf_packet_index index; |
d41f73b7 MD |
1276 | |
1277 | DBG("In read_subbuffer (infd : %d)", infd); | |
309167d2 | 1278 | |
d41f73b7 MD |
1279 | /* Get the next subbuffer */ |
1280 | err = kernctl_get_next_subbuf(infd); | |
1281 | if (err != 0) { | |
d41f73b7 MD |
1282 | /* |
1283 | * This is a debug message even for single-threaded consumer, | |
1284 | * because poll() have more relaxed criterions than get subbuf, | |
1285 | * so get_subbuf may fail for short race windows where poll() | |
1286 | * would issue wakeups. | |
1287 | */ | |
1288 | DBG("Reserving sub buffer failed (everything is normal, " | |
1289 | "it is due to concurrency)"); | |
56591bac | 1290 | ret = -errno; |
d41f73b7 MD |
1291 | goto end; |
1292 | } | |
1293 | ||
1d4dfdef DG |
1294 | /* Get the full subbuffer size including padding */ |
1295 | err = kernctl_get_padded_subbuf_size(infd, &len); | |
1296 | if (err != 0) { | |
5a510c9f | 1297 | PERROR("Getting sub-buffer len failed."); |
8265f19e MD |
1298 | err = kernctl_put_subbuf(infd); |
1299 | if (err != 0) { | |
1300 | if (errno == EFAULT) { | |
5a510c9f | 1301 | PERROR("Error in unreserving sub buffer\n"); |
8265f19e MD |
1302 | } else if (errno == EIO) { |
1303 | /* Should never happen with newer LTTng versions */ | |
5a510c9f | 1304 | PERROR("Reader has been pushed by the writer, last sub-buffer corrupted."); |
8265f19e MD |
1305 | } |
1306 | ret = -errno; | |
1307 | goto end; | |
1308 | } | |
56591bac | 1309 | ret = -errno; |
1d4dfdef DG |
1310 | goto end; |
1311 | } | |
1312 | ||
1c20f0e2 | 1313 | if (!stream->metadata_flag) { |
309167d2 JD |
1314 | ret = get_index_values(&index, infd); |
1315 | if (ret < 0) { | |
8265f19e MD |
1316 | err = kernctl_put_subbuf(infd); |
1317 | if (err != 0) { | |
1318 | if (errno == EFAULT) { | |
5a510c9f | 1319 | PERROR("Error in unreserving sub buffer\n"); |
8265f19e MD |
1320 | } else if (errno == EIO) { |
1321 | /* Should never happen with newer LTTng versions */ | |
5a510c9f | 1322 | PERROR("Reader has been pushed by the writer, last sub-buffer corrupted."); |
8265f19e MD |
1323 | } |
1324 | ret = -errno; | |
1325 | goto end; | |
1326 | } | |
309167d2 JD |
1327 | goto end; |
1328 | } | |
fb83fe64 JD |
1329 | ret = update_stream_stats(stream); |
1330 | if (ret < 0) { | |
c3c60f7d MD |
1331 | err = kernctl_put_subbuf(infd); |
1332 | if (err != 0) { | |
1333 | if (err == -EFAULT) { | |
1334 | PERROR("Error in unreserving sub buffer\n"); | |
1335 | } else if (err == -EIO) { | |
1336 | /* Should never happen with newer LTTng versions */ | |
1337 | PERROR("Reader has been pushed by the writer, last sub-buffer corrupted."); | |
1338 | } | |
1339 | ret = err; | |
1340 | goto end; | |
1341 | } | |
fb83fe64 JD |
1342 | goto end; |
1343 | } | |
1c20f0e2 JD |
1344 | } else { |
1345 | write_index = 0; | |
93ec662e JD |
1346 | ret = metadata_stream_check_version(infd, stream); |
1347 | if (ret < 0) { | |
c3c60f7d MD |
1348 | err = kernctl_put_subbuf(infd); |
1349 | if (err != 0) { | |
1350 | if (err == -EFAULT) { | |
1351 | PERROR("Error in unreserving sub buffer\n"); | |
1352 | } else if (err == -EIO) { | |
1353 | /* Should never happen with newer LTTng versions */ | |
1354 | PERROR("Reader has been pushed by the writer, last sub-buffer corrupted."); | |
1355 | } | |
1356 | ret = err; | |
1357 | goto end; | |
1358 | } | |
93ec662e JD |
1359 | goto end; |
1360 | } | |
309167d2 JD |
1361 | } |
1362 | ||
ffe60014 | 1363 | switch (stream->chan->output) { |
07b86b52 | 1364 | case CONSUMER_CHANNEL_SPLICE: |
1d4dfdef DG |
1365 | /* |
1366 | * XXX: The lttng-modules splice "actor" does not handle copying | |
1367 | * partial pages hence only using the subbuffer size without the | |
1368 | * padding makes the splice fail. | |
1369 | */ | |
1370 | subbuf_size = len; | |
1371 | padding = 0; | |
1372 | ||
1373 | /* splice the subbuffer to the tracefile */ | |
91dfef6e | 1374 | ret = lttng_consumer_on_read_subbuffer_splice(ctx, stream, subbuf_size, |
309167d2 | 1375 | padding, &index); |
91dfef6e DG |
1376 | /* |
1377 | * XXX: Splice does not support network streaming so the return value | |
1378 | * is simply checked against subbuf_size and not like the mmap() op. | |
1379 | */ | |
1d4dfdef DG |
1380 | if (ret != subbuf_size) { |
1381 | /* | |
1382 | * display the error but continue processing to try | |
1383 | * to release the subbuffer | |
1384 | */ | |
1385 | ERR("Error splicing to tracefile (ret: %zd != len: %lu)", | |
1386 | ret, subbuf_size); | |
309167d2 | 1387 | write_index = 0; |
1d4dfdef DG |
1388 | } |
1389 | break; | |
07b86b52 | 1390 | case CONSUMER_CHANNEL_MMAP: |
1d4dfdef DG |
1391 | /* Get subbuffer size without padding */ |
1392 | err = kernctl_get_subbuf_size(infd, &subbuf_size); | |
1393 | if (err != 0) { | |
5a510c9f | 1394 | PERROR("Getting sub-buffer len failed."); |
8265f19e MD |
1395 | err = kernctl_put_subbuf(infd); |
1396 | if (err != 0) { | |
1397 | if (errno == EFAULT) { | |
5a510c9f | 1398 | PERROR("Error in unreserving sub buffer\n"); |
8265f19e MD |
1399 | } else if (errno == EIO) { |
1400 | /* Should never happen with newer LTTng versions */ | |
5a510c9f | 1401 | PERROR("Reader has been pushed by the writer, last sub-buffer corrupted."); |
8265f19e MD |
1402 | } |
1403 | ret = -errno; | |
1404 | goto end; | |
1405 | } | |
56591bac | 1406 | ret = -errno; |
1d4dfdef DG |
1407 | goto end; |
1408 | } | |
47e81c02 | 1409 | |
1d4dfdef DG |
1410 | /* Make sure the tracer is not gone mad on us! */ |
1411 | assert(len >= subbuf_size); | |
1412 | ||
1413 | padding = len - subbuf_size; | |
1414 | ||
1415 | /* write the subbuffer to the tracefile */ | |
91dfef6e | 1416 | ret = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, subbuf_size, |
309167d2 | 1417 | padding, &index); |
91dfef6e DG |
1418 | /* |
1419 | * The mmap operation should write subbuf_size amount of data when | |
1420 | * network streaming or the full padding (len) size when we are _not_ | |
1421 | * streaming. | |
1422 | */ | |
d88aee68 DG |
1423 | if ((ret != subbuf_size && stream->net_seq_idx != (uint64_t) -1ULL) || |
1424 | (ret != len && stream->net_seq_idx == (uint64_t) -1ULL)) { | |
1d4dfdef | 1425 | /* |
91dfef6e | 1426 | * Display the error but continue processing to try to release the |
2336629e DG |
1427 | * subbuffer. This is a DBG statement since this is possible to |
1428 | * happen without being a critical error. | |
1d4dfdef | 1429 | */ |
2336629e | 1430 | DBG("Error writing to tracefile " |
91dfef6e DG |
1431 | "(ret: %zd != len: %lu != subbuf_size: %lu)", |
1432 | ret, len, subbuf_size); | |
309167d2 | 1433 | write_index = 0; |
1d4dfdef DG |
1434 | } |
1435 | break; | |
1436 | default: | |
1437 | ERR("Unknown output method"); | |
56591bac | 1438 | ret = -EPERM; |
d41f73b7 MD |
1439 | } |
1440 | ||
1441 | err = kernctl_put_next_subbuf(infd); | |
1442 | if (err != 0) { | |
d41f73b7 | 1443 | if (errno == EFAULT) { |
5a510c9f | 1444 | PERROR("Error in unreserving sub buffer\n"); |
d41f73b7 MD |
1445 | } else if (errno == EIO) { |
1446 | /* Should never happen with newer LTTng versions */ | |
5a510c9f | 1447 | PERROR("Reader has been pushed by the writer, last sub-buffer corrupted."); |
d41f73b7 | 1448 | } |
56591bac | 1449 | ret = -errno; |
d41f73b7 MD |
1450 | goto end; |
1451 | } | |
1452 | ||
309167d2 | 1453 | /* Write index if needed. */ |
1c20f0e2 JD |
1454 | if (!write_index) { |
1455 | goto end; | |
1456 | } | |
1457 | ||
94d49140 JD |
1458 | if (stream->chan->live_timer_interval && !stream->metadata_flag) { |
1459 | /* | |
1460 | * In live, block until all the metadata is sent. | |
1461 | */ | |
c585821b MD |
1462 | pthread_mutex_lock(&stream->metadata_timer_lock); |
1463 | assert(!stream->missed_metadata_flush); | |
1464 | stream->waiting_on_metadata = true; | |
1465 | pthread_mutex_unlock(&stream->metadata_timer_lock); | |
1466 | ||
94d49140 | 1467 | err = consumer_stream_sync_metadata(ctx, stream->session_id); |
c585821b MD |
1468 | |
1469 | pthread_mutex_lock(&stream->metadata_timer_lock); | |
1470 | stream->waiting_on_metadata = false; | |
1471 | if (stream->missed_metadata_flush) { | |
1472 | stream->missed_metadata_flush = false; | |
1473 | pthread_mutex_unlock(&stream->metadata_timer_lock); | |
1474 | (void) consumer_flush_kernel_index(stream); | |
1475 | } else { | |
1476 | pthread_mutex_unlock(&stream->metadata_timer_lock); | |
1477 | } | |
94d49140 JD |
1478 | if (err < 0) { |
1479 | goto end; | |
1480 | } | |
1481 | } | |
1482 | ||
1c20f0e2 JD |
1483 | err = consumer_stream_write_index(stream, &index); |
1484 | if (err < 0) { | |
1485 | goto end; | |
309167d2 JD |
1486 | } |
1487 | ||
d41f73b7 MD |
1488 | end: |
1489 | return ret; | |
1490 | } | |
1491 | ||
1492 | int lttng_kconsumer_on_recv_stream(struct lttng_consumer_stream *stream) | |
1493 | { | |
1494 | int ret; | |
ffe60014 DG |
1495 | |
1496 | assert(stream); | |
1497 | ||
2bba9e53 DG |
1498 | /* |
1499 | * Don't create anything if this is set for streaming or should not be | |
1500 | * monitored. | |
1501 | */ | |
1502 | if (stream->net_seq_idx == (uint64_t) -1ULL && stream->chan->monitor) { | |
fe4477ee JD |
1503 | ret = utils_create_stream_file(stream->chan->pathname, stream->name, |
1504 | stream->chan->tracefile_size, stream->tracefile_count_current, | |
309167d2 | 1505 | stream->uid, stream->gid, NULL); |
fe4477ee JD |
1506 | if (ret < 0) { |
1507 | goto error; | |
1508 | } | |
1509 | stream->out_fd = ret; | |
1510 | stream->tracefile_size_current = 0; | |
309167d2 JD |
1511 | |
1512 | if (!stream->metadata_flag) { | |
8dbd7d83 MD |
1513 | struct lttng_index_file *index_file; |
1514 | ||
1515 | index_file = lttng_index_file_create(stream->chan->pathname, | |
309167d2 JD |
1516 | stream->name, stream->uid, stream->gid, |
1517 | stream->chan->tracefile_size, | |
8dbd7d83 MD |
1518 | stream->tracefile_count_current, |
1519 | CTF_INDEX_MAJOR, CTF_INDEX_MINOR); | |
1520 | if (!index_file) { | |
309167d2 JD |
1521 | goto error; |
1522 | } | |
8dbd7d83 | 1523 | stream->index_file = index_file; |
309167d2 | 1524 | } |
ffe60014 | 1525 | } |
d41f73b7 | 1526 | |
d41f73b7 MD |
1527 | if (stream->output == LTTNG_EVENT_MMAP) { |
1528 | /* get the len of the mmap region */ | |
1529 | unsigned long mmap_len; | |
1530 | ||
1531 | ret = kernctl_get_mmap_len(stream->wait_fd, &mmap_len); | |
1532 | if (ret != 0) { | |
ffe60014 | 1533 | PERROR("kernctl_get_mmap_len"); |
56591bac | 1534 | ret = -errno; |
d41f73b7 MD |
1535 | goto error_close_fd; |
1536 | } | |
1537 | stream->mmap_len = (size_t) mmap_len; | |
1538 | ||
ffe60014 DG |
1539 | stream->mmap_base = mmap(NULL, stream->mmap_len, PROT_READ, |
1540 | MAP_PRIVATE, stream->wait_fd, 0); | |
d41f73b7 | 1541 | if (stream->mmap_base == MAP_FAILED) { |
ffe60014 | 1542 | PERROR("Error mmaping"); |
d41f73b7 MD |
1543 | ret = -1; |
1544 | goto error_close_fd; | |
1545 | } | |
1546 | } | |
1547 | ||
1548 | /* we return 0 to let the library handle the FD internally */ | |
1549 | return 0; | |
1550 | ||
1551 | error_close_fd: | |
2f225ce2 | 1552 | if (stream->out_fd >= 0) { |
d41f73b7 MD |
1553 | int err; |
1554 | ||
1555 | err = close(stream->out_fd); | |
1556 | assert(!err); | |
2f225ce2 | 1557 | stream->out_fd = -1; |
d41f73b7 MD |
1558 | } |
1559 | error: | |
1560 | return ret; | |
1561 | } | |
1562 | ||
ca22feea DG |
1563 | /* |
1564 | * Check if data is still being extracted from the buffers for a specific | |
4e9a4686 DG |
1565 | * stream. Consumer data lock MUST be acquired before calling this function |
1566 | * and the stream lock. | |
ca22feea | 1567 | * |
6d805429 | 1568 | * Return 1 if the traced data are still getting read else 0 meaning that the |
ca22feea DG |
1569 | * data is available for trace viewer reading. |
1570 | */ | |
6d805429 | 1571 | int lttng_kconsumer_data_pending(struct lttng_consumer_stream *stream) |
ca22feea DG |
1572 | { |
1573 | int ret; | |
1574 | ||
1575 | assert(stream); | |
1576 | ||
873b9e9a MD |
1577 | if (stream->endpoint_status != CONSUMER_ENDPOINT_ACTIVE) { |
1578 | ret = 0; | |
1579 | goto end; | |
1580 | } | |
1581 | ||
ca22feea DG |
1582 | ret = kernctl_get_next_subbuf(stream->wait_fd); |
1583 | if (ret == 0) { | |
1584 | /* There is still data so let's put back this subbuffer. */ | |
1585 | ret = kernctl_put_subbuf(stream->wait_fd); | |
1586 | assert(ret == 0); | |
6d805429 | 1587 | ret = 1; /* Data is pending */ |
4e9a4686 | 1588 | goto end; |
ca22feea DG |
1589 | } |
1590 | ||
6d805429 DG |
1591 | /* Data is NOT pending and ready to be read. */ |
1592 | ret = 0; | |
ca22feea | 1593 | |
6efae65e DG |
1594 | end: |
1595 | return ret; | |
ca22feea | 1596 | } |