Commit | Line | Data |
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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 | |
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 | |
990570ed | 32 | #include <common/common.h> |
10a8a223 | 33 | #include <common/kernel-ctl/kernel-ctl.h> |
10a8a223 | 34 | #include <common/sessiond-comm/sessiond-comm.h> |
00e2e675 | 35 | #include <common/sessiond-comm/relayd.h> |
dbb5dfe6 | 36 | #include <common/compat/fcntl.h> |
00e2e675 | 37 | #include <common/relayd/relayd.h> |
0857097f | 38 | |
10a8a223 | 39 | #include "kernel-consumer.h" |
3bd1e081 MD |
40 | |
41 | extern struct lttng_consumer_global_data consumer_data; | |
42 | extern int consumer_poll_timeout; | |
43 | extern volatile int consumer_quit; | |
44 | ||
3bd1e081 MD |
45 | /* |
46 | * Take a snapshot for a specific fd | |
47 | * | |
48 | * Returns 0 on success, < 0 on error | |
49 | */ | |
ffe60014 | 50 | int lttng_kconsumer_take_snapshot(struct lttng_consumer_stream *stream) |
3bd1e081 MD |
51 | { |
52 | int ret = 0; | |
53 | int infd = stream->wait_fd; | |
54 | ||
55 | ret = kernctl_snapshot(infd); | |
56 | if (ret != 0) { | |
87dc6a9c | 57 | errno = -ret; |
3bd1e081 MD |
58 | perror("Getting sub-buffer snapshot."); |
59 | } | |
60 | ||
61 | return ret; | |
62 | } | |
63 | ||
64 | /* | |
65 | * Get the produced position | |
66 | * | |
67 | * Returns 0 on success, < 0 on error | |
68 | */ | |
ffe60014 | 69 | int lttng_kconsumer_get_produced_snapshot(struct lttng_consumer_stream *stream, |
3bd1e081 MD |
70 | unsigned long *pos) |
71 | { | |
72 | int ret; | |
73 | int infd = stream->wait_fd; | |
74 | ||
75 | ret = kernctl_snapshot_get_produced(infd, pos); | |
76 | if (ret != 0) { | |
87dc6a9c | 77 | errno = -ret; |
3bd1e081 MD |
78 | perror("kernctl_snapshot_get_produced"); |
79 | } | |
80 | ||
81 | return ret; | |
82 | } | |
83 | ||
84 | int lttng_kconsumer_recv_cmd(struct lttng_consumer_local_data *ctx, | |
85 | int sock, struct pollfd *consumer_sockpoll) | |
86 | { | |
87 | ssize_t ret; | |
f50f23d9 | 88 | enum lttng_error_code ret_code = LTTNG_OK; |
3bd1e081 MD |
89 | struct lttcomm_consumer_msg msg; |
90 | ||
91 | ret = lttcomm_recv_unix_sock(sock, &msg, sizeof(msg)); | |
92 | if (ret != sizeof(msg)) { | |
f73fabfd | 93 | lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_ERROR_RECV_CMD); |
3bd1e081 MD |
94 | return ret; |
95 | } | |
96 | if (msg.cmd_type == LTTNG_CONSUMER_STOP) { | |
f50f23d9 DG |
97 | /* |
98 | * Notify the session daemon that the command is completed. | |
99 | * | |
100 | * On transport layer error, the function call will print an error | |
101 | * message so handling the returned code is a bit useless since we | |
102 | * return an error code anyway. | |
103 | */ | |
104 | (void) consumer_send_status_msg(sock, ret_code); | |
3bd1e081 MD |
105 | return -ENOENT; |
106 | } | |
107 | ||
b0b335c8 MD |
108 | /* relayd needs RCU read-side protection */ |
109 | rcu_read_lock(); | |
110 | ||
3bd1e081 | 111 | switch (msg.cmd_type) { |
00e2e675 DG |
112 | case LTTNG_CONSUMER_ADD_RELAYD_SOCKET: |
113 | { | |
f50f23d9 | 114 | /* Session daemon status message are handled in the following call. */ |
7735ef9e DG |
115 | ret = consumer_add_relayd_socket(msg.u.relayd_sock.net_index, |
116 | msg.u.relayd_sock.type, ctx, sock, consumer_sockpoll, | |
46e6455f | 117 | &msg.u.relayd_sock.sock, msg.u.relayd_sock.session_id); |
00e2e675 DG |
118 | goto end_nosignal; |
119 | } | |
3bd1e081 MD |
120 | case LTTNG_CONSUMER_ADD_CHANNEL: |
121 | { | |
122 | struct lttng_consumer_channel *new_channel; | |
123 | ||
f50f23d9 DG |
124 | /* First send a status message before receiving the fds. */ |
125 | ret = consumer_send_status_msg(sock, ret_code); | |
126 | if (ret < 0) { | |
127 | /* Somehow, the session daemon is not responding anymore. */ | |
128 | goto end_nosignal; | |
129 | } | |
130 | ||
d88aee68 | 131 | DBG("consumer_add_channel %" PRIu64, msg.u.channel.channel_key); |
3bd1e081 | 132 | new_channel = consumer_allocate_channel(msg.u.channel.channel_key, |
ffe60014 DG |
133 | msg.u.channel.session_id, msg.u.channel.pathname, |
134 | msg.u.channel.name, msg.u.channel.uid, msg.u.channel.gid, | |
135 | msg.u.channel.relayd_id, msg.u.channel.output); | |
3bd1e081 | 136 | if (new_channel == NULL) { |
f73fabfd | 137 | lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_OUTFD_ERROR); |
3bd1e081 MD |
138 | goto end_nosignal; |
139 | } | |
ffe60014 DG |
140 | new_channel->nb_init_stream_left = msg.u.channel.nb_init_streams; |
141 | ||
142 | /* Translate and save channel type. */ | |
143 | switch (msg.u.channel.type) { | |
144 | case CONSUMER_CHANNEL_TYPE_DATA: | |
145 | case CONSUMER_CHANNEL_TYPE_METADATA: | |
146 | new_channel->type = msg.u.channel.type; | |
147 | break; | |
148 | default: | |
149 | assert(0); | |
150 | goto end_nosignal; | |
151 | }; | |
152 | ||
3bd1e081 MD |
153 | if (ctx->on_recv_channel != NULL) { |
154 | ret = ctx->on_recv_channel(new_channel); | |
155 | if (ret == 0) { | |
d8ef542d | 156 | consumer_add_channel(new_channel, ctx); |
3bd1e081 MD |
157 | } else if (ret < 0) { |
158 | goto end_nosignal; | |
159 | } | |
160 | } else { | |
d8ef542d | 161 | consumer_add_channel(new_channel, ctx); |
3bd1e081 MD |
162 | } |
163 | goto end_nosignal; | |
164 | } | |
165 | case LTTNG_CONSUMER_ADD_STREAM: | |
166 | { | |
50f8ae69 | 167 | int fd, stream_pipe; |
00e2e675 DG |
168 | struct consumer_relayd_sock_pair *relayd = NULL; |
169 | struct lttng_consumer_stream *new_stream; | |
ffe60014 | 170 | struct lttng_consumer_channel *channel; |
c80048c6 | 171 | int alloc_ret = 0; |
3bd1e081 | 172 | |
ffe60014 DG |
173 | /* |
174 | * Get stream's channel reference. Needed when adding the stream to the | |
175 | * global hash table. | |
176 | */ | |
177 | channel = consumer_find_channel(msg.u.stream.channel_key); | |
178 | if (!channel) { | |
179 | /* | |
180 | * We could not find the channel. Can happen if cpu hotplug | |
181 | * happens while tearing down. | |
182 | */ | |
d88aee68 | 183 | ERR("Unable to find channel key %" PRIu64, msg.u.stream.channel_key); |
ffe60014 DG |
184 | ret_code = LTTNG_ERR_KERN_CHAN_NOT_FOUND; |
185 | } | |
186 | ||
f50f23d9 DG |
187 | /* First send a status message before receiving the fds. */ |
188 | ret = consumer_send_status_msg(sock, ret_code); | |
ffe60014 DG |
189 | if (ret < 0 || ret_code != LTTNG_OK) { |
190 | /* | |
191 | * Somehow, the session daemon is not responding anymore or the | |
192 | * channel was not found. | |
193 | */ | |
f50f23d9 DG |
194 | goto end_nosignal; |
195 | } | |
196 | ||
3bd1e081 MD |
197 | /* block */ |
198 | if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) { | |
3f8e211f | 199 | rcu_read_unlock(); |
3bd1e081 MD |
200 | return -EINTR; |
201 | } | |
00e2e675 DG |
202 | |
203 | /* Get stream file descriptor from socket */ | |
f2fc6720 MD |
204 | ret = lttcomm_recv_fds_unix_sock(sock, &fd, 1); |
205 | if (ret != sizeof(fd)) { | |
f73fabfd | 206 | lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_ERROR_RECV_FD); |
3f8e211f | 207 | rcu_read_unlock(); |
3bd1e081 MD |
208 | return ret; |
209 | } | |
3bd1e081 | 210 | |
f50f23d9 DG |
211 | /* |
212 | * Send status code to session daemon only if the recv works. If the | |
213 | * above recv() failed, the session daemon is notified through the | |
214 | * error socket and the teardown is eventually done. | |
215 | */ | |
216 | ret = consumer_send_status_msg(sock, ret_code); | |
217 | if (ret < 0) { | |
218 | /* Somehow, the session daemon is not responding anymore. */ | |
219 | goto end_nosignal; | |
220 | } | |
221 | ||
ffe60014 DG |
222 | new_stream = consumer_allocate_stream(channel->key, |
223 | fd, | |
224 | LTTNG_CONSUMER_ACTIVE_STREAM, | |
225 | channel->name, | |
226 | channel->uid, | |
227 | channel->gid, | |
228 | channel->relayd_id, | |
229 | channel->session_id, | |
230 | msg.u.stream.cpu, | |
231 | &alloc_ret, | |
232 | channel->type); | |
3bd1e081 | 233 | if (new_stream == NULL) { |
c80048c6 MD |
234 | switch (alloc_ret) { |
235 | case -ENOMEM: | |
236 | case -EINVAL: | |
237 | default: | |
238 | lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_OUTFD_ERROR); | |
239 | break; | |
c80048c6 | 240 | } |
3f8e211f | 241 | goto end_nosignal; |
3bd1e081 | 242 | } |
ffe60014 DG |
243 | new_stream->chan = channel; |
244 | new_stream->wait_fd = fd; | |
00e2e675 | 245 | |
fb3a43a9 DG |
246 | /* |
247 | * The buffer flush is done on the session daemon side for the kernel | |
248 | * so no need for the stream "hangup_flush_done" variable to be | |
249 | * tracked. This is important for a kernel stream since we don't rely | |
250 | * on the flush state of the stream to read data. It's not the case for | |
251 | * user space tracing. | |
252 | */ | |
253 | new_stream->hangup_flush_done = 0; | |
254 | ||
00e2e675 | 255 | /* The stream is not metadata. Get relayd reference if exists. */ |
ffe60014 | 256 | relayd = consumer_find_relayd(new_stream->net_seq_idx); |
00e2e675 DG |
257 | if (relayd != NULL) { |
258 | /* Add stream on the relayd */ | |
259 | pthread_mutex_lock(&relayd->ctrl_sock_mutex); | |
260 | ret = relayd_add_stream(&relayd->control_sock, | |
ffe60014 | 261 | new_stream->name, new_stream->chan->pathname, |
00e2e675 DG |
262 | &new_stream->relayd_stream_id); |
263 | pthread_mutex_unlock(&relayd->ctrl_sock_mutex); | |
264 | if (ret < 0) { | |
e316aad5 | 265 | consumer_del_stream(new_stream, NULL); |
3f8e211f | 266 | goto end_nosignal; |
00e2e675 | 267 | } |
d88aee68 DG |
268 | } else if (new_stream->net_seq_idx != (uint64_t) -1ULL) { |
269 | ERR("Network sequence index %" PRIu64 " unknown. Not adding stream.", | |
ffe60014 | 270 | new_stream->net_seq_idx); |
e316aad5 | 271 | consumer_del_stream(new_stream, NULL); |
3f8e211f | 272 | goto end_nosignal; |
00e2e675 DG |
273 | } |
274 | ||
633d0084 DG |
275 | if (ctx->on_recv_stream) { |
276 | ret = ctx->on_recv_stream(new_stream); | |
277 | if (ret < 0) { | |
e316aad5 | 278 | consumer_del_stream(new_stream, NULL); |
633d0084 | 279 | goto end_nosignal; |
fb3a43a9 | 280 | } |
633d0084 | 281 | } |
fb3a43a9 | 282 | |
50f8ae69 | 283 | /* Get the right pipe where the stream will be sent. */ |
633d0084 | 284 | if (new_stream->metadata_flag) { |
50f8ae69 | 285 | stream_pipe = ctx->consumer_metadata_pipe[1]; |
3bd1e081 | 286 | } else { |
50f8ae69 DG |
287 | stream_pipe = ctx->consumer_data_pipe[1]; |
288 | } | |
289 | ||
290 | do { | |
291 | ret = write(stream_pipe, &new_stream, sizeof(new_stream)); | |
292 | } while (ret < 0 && errno == EINTR); | |
293 | if (ret < 0) { | |
294 | PERROR("Consumer write %s stream to pipe %d", | |
295 | new_stream->metadata_flag ? "metadata" : "data", | |
296 | stream_pipe); | |
297 | consumer_del_stream(new_stream, NULL); | |
298 | goto end_nosignal; | |
3bd1e081 | 299 | } |
00e2e675 | 300 | |
50f8ae69 | 301 | DBG("Kernel consumer ADD_STREAM %s (fd: %d) with relayd id %" PRIu64, |
ffe60014 | 302 | new_stream->name, fd, new_stream->relayd_stream_id); |
3bd1e081 MD |
303 | break; |
304 | } | |
305 | case LTTNG_CONSUMER_UPDATE_STREAM: | |
306 | { | |
3f8e211f DG |
307 | rcu_read_unlock(); |
308 | return -ENOSYS; | |
309 | } | |
310 | case LTTNG_CONSUMER_DESTROY_RELAYD: | |
311 | { | |
a6ba4fe1 | 312 | uint64_t index = msg.u.destroy_relayd.net_seq_idx; |
3f8e211f DG |
313 | struct consumer_relayd_sock_pair *relayd; |
314 | ||
a6ba4fe1 | 315 | DBG("Kernel consumer destroying relayd %" PRIu64, index); |
3f8e211f DG |
316 | |
317 | /* Get relayd reference if exists. */ | |
a6ba4fe1 | 318 | relayd = consumer_find_relayd(index); |
3f8e211f | 319 | if (relayd == NULL) { |
3448e266 | 320 | DBG("Unable to find relayd %" PRIu64, index); |
f50f23d9 | 321 | ret_code = LTTNG_ERR_NO_CONSUMER; |
3bd1e081 | 322 | } |
3f8e211f | 323 | |
a6ba4fe1 DG |
324 | /* |
325 | * Each relayd socket pair has a refcount of stream attached to it | |
326 | * which tells if the relayd is still active or not depending on the | |
327 | * refcount value. | |
328 | * | |
329 | * This will set the destroy flag of the relayd object and destroy it | |
330 | * if the refcount reaches zero when called. | |
331 | * | |
332 | * The destroy can happen either here or when a stream fd hangs up. | |
333 | */ | |
f50f23d9 DG |
334 | if (relayd) { |
335 | consumer_flag_relayd_for_destroy(relayd); | |
336 | } | |
337 | ||
338 | ret = consumer_send_status_msg(sock, ret_code); | |
339 | if (ret < 0) { | |
340 | /* Somehow, the session daemon is not responding anymore. */ | |
341 | goto end_nosignal; | |
342 | } | |
3f8e211f | 343 | |
3f8e211f | 344 | goto end_nosignal; |
3bd1e081 | 345 | } |
6d805429 | 346 | case LTTNG_CONSUMER_DATA_PENDING: |
53632229 | 347 | { |
c8f59ee5 | 348 | int32_t ret; |
6d805429 | 349 | uint64_t id = msg.u.data_pending.session_id; |
c8f59ee5 | 350 | |
6d805429 | 351 | DBG("Kernel consumer data pending command for id %" PRIu64, id); |
c8f59ee5 | 352 | |
6d805429 | 353 | ret = consumer_data_pending(id); |
c8f59ee5 DG |
354 | |
355 | /* Send back returned value to session daemon */ | |
356 | ret = lttcomm_send_unix_sock(sock, &ret, sizeof(ret)); | |
357 | if (ret < 0) { | |
6d805429 | 358 | PERROR("send data pending ret code"); |
c8f59ee5 | 359 | } |
f50f23d9 DG |
360 | |
361 | /* | |
362 | * No need to send back a status message since the data pending | |
363 | * returned value is the response. | |
364 | */ | |
c8f59ee5 | 365 | break; |
53632229 | 366 | } |
3bd1e081 | 367 | default: |
3f8e211f | 368 | goto end_nosignal; |
3bd1e081 | 369 | } |
3f8e211f | 370 | |
3bd1e081 | 371 | end_nosignal: |
b0b335c8 | 372 | rcu_read_unlock(); |
4cbc1a04 DG |
373 | |
374 | /* | |
375 | * Return 1 to indicate success since the 0 value can be a socket | |
376 | * shutdown during the recv() or send() call. | |
377 | */ | |
378 | return 1; | |
3bd1e081 | 379 | } |
d41f73b7 MD |
380 | |
381 | /* | |
382 | * Consume data on a file descriptor and write it on a trace file. | |
383 | */ | |
4078b776 | 384 | ssize_t lttng_kconsumer_read_subbuffer(struct lttng_consumer_stream *stream, |
d41f73b7 MD |
385 | struct lttng_consumer_local_data *ctx) |
386 | { | |
1d4dfdef | 387 | unsigned long len, subbuf_size, padding; |
d41f73b7 | 388 | int err; |
4078b776 | 389 | ssize_t ret = 0; |
d41f73b7 MD |
390 | int infd = stream->wait_fd; |
391 | ||
392 | DBG("In read_subbuffer (infd : %d)", infd); | |
393 | /* Get the next subbuffer */ | |
394 | err = kernctl_get_next_subbuf(infd); | |
395 | if (err != 0) { | |
1d4dfdef | 396 | ret = err; |
d41f73b7 MD |
397 | /* |
398 | * This is a debug message even for single-threaded consumer, | |
399 | * because poll() have more relaxed criterions than get subbuf, | |
400 | * so get_subbuf may fail for short race windows where poll() | |
401 | * would issue wakeups. | |
402 | */ | |
403 | DBG("Reserving sub buffer failed (everything is normal, " | |
404 | "it is due to concurrency)"); | |
405 | goto end; | |
406 | } | |
407 | ||
1d4dfdef DG |
408 | /* Get the full subbuffer size including padding */ |
409 | err = kernctl_get_padded_subbuf_size(infd, &len); | |
410 | if (err != 0) { | |
411 | errno = -err; | |
412 | perror("Getting sub-buffer len failed."); | |
413 | ret = err; | |
414 | goto end; | |
415 | } | |
416 | ||
ffe60014 | 417 | switch (stream->chan->output) { |
1d4dfdef | 418 | case LTTNG_EVENT_SPLICE: |
d41f73b7 | 419 | |
1d4dfdef DG |
420 | /* |
421 | * XXX: The lttng-modules splice "actor" does not handle copying | |
422 | * partial pages hence only using the subbuffer size without the | |
423 | * padding makes the splice fail. | |
424 | */ | |
425 | subbuf_size = len; | |
426 | padding = 0; | |
427 | ||
428 | /* splice the subbuffer to the tracefile */ | |
91dfef6e DG |
429 | ret = lttng_consumer_on_read_subbuffer_splice(ctx, stream, subbuf_size, |
430 | padding); | |
431 | /* | |
432 | * XXX: Splice does not support network streaming so the return value | |
433 | * is simply checked against subbuf_size and not like the mmap() op. | |
434 | */ | |
1d4dfdef DG |
435 | if (ret != subbuf_size) { |
436 | /* | |
437 | * display the error but continue processing to try | |
438 | * to release the subbuffer | |
439 | */ | |
440 | ERR("Error splicing to tracefile (ret: %zd != len: %lu)", | |
441 | ret, subbuf_size); | |
442 | } | |
443 | break; | |
444 | case LTTNG_EVENT_MMAP: | |
445 | /* Get subbuffer size without padding */ | |
446 | err = kernctl_get_subbuf_size(infd, &subbuf_size); | |
447 | if (err != 0) { | |
448 | errno = -err; | |
449 | perror("Getting sub-buffer len failed."); | |
450 | ret = err; | |
451 | goto end; | |
452 | } | |
47e81c02 | 453 | |
1d4dfdef DG |
454 | /* Make sure the tracer is not gone mad on us! */ |
455 | assert(len >= subbuf_size); | |
456 | ||
457 | padding = len - subbuf_size; | |
458 | ||
459 | /* write the subbuffer to the tracefile */ | |
91dfef6e DG |
460 | ret = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, subbuf_size, |
461 | padding); | |
462 | /* | |
463 | * The mmap operation should write subbuf_size amount of data when | |
464 | * network streaming or the full padding (len) size when we are _not_ | |
465 | * streaming. | |
466 | */ | |
d88aee68 DG |
467 | if ((ret != subbuf_size && stream->net_seq_idx != (uint64_t) -1ULL) || |
468 | (ret != len && stream->net_seq_idx == (uint64_t) -1ULL)) { | |
1d4dfdef | 469 | /* |
91dfef6e DG |
470 | * Display the error but continue processing to try to release the |
471 | * subbuffer | |
1d4dfdef | 472 | */ |
91dfef6e DG |
473 | ERR("Error writing to tracefile " |
474 | "(ret: %zd != len: %lu != subbuf_size: %lu)", | |
475 | ret, len, subbuf_size); | |
1d4dfdef DG |
476 | } |
477 | break; | |
478 | default: | |
479 | ERR("Unknown output method"); | |
480 | ret = -1; | |
d41f73b7 MD |
481 | } |
482 | ||
483 | err = kernctl_put_next_subbuf(infd); | |
484 | if (err != 0) { | |
21073eaa | 485 | errno = -err; |
d41f73b7 MD |
486 | if (errno == EFAULT) { |
487 | perror("Error in unreserving sub buffer\n"); | |
488 | } else if (errno == EIO) { | |
489 | /* Should never happen with newer LTTng versions */ | |
490 | perror("Reader has been pushed by the writer, last sub-buffer corrupted."); | |
491 | } | |
21073eaa DG |
492 | |
493 | ret = -err; | |
d41f73b7 MD |
494 | goto end; |
495 | } | |
496 | ||
497 | end: | |
498 | return ret; | |
499 | } | |
500 | ||
501 | int lttng_kconsumer_on_recv_stream(struct lttng_consumer_stream *stream) | |
502 | { | |
503 | int ret; | |
ffe60014 DG |
504 | char full_path[PATH_MAX]; |
505 | ||
506 | assert(stream); | |
507 | ||
508 | ret = snprintf(full_path, sizeof(full_path), "%s/%s", | |
509 | stream->chan->pathname, stream->name); | |
510 | if (ret < 0) { | |
511 | PERROR("snprintf on_recv_stream"); | |
512 | goto error; | |
513 | } | |
d41f73b7 MD |
514 | |
515 | /* Opening the tracefile in write mode */ | |
d88aee68 | 516 | if (stream->net_seq_idx == (uint64_t) -1ULL) { |
ffe60014 DG |
517 | ret = run_as_open(full_path, O_WRONLY | O_CREAT | O_TRUNC, |
518 | S_IRWXU|S_IRWXG|S_IRWXO, stream->uid, stream->gid); | |
d41f73b7 | 519 | if (ret < 0) { |
ffe60014 | 520 | PERROR("open kernel stream path %s", full_path); |
d41f73b7 MD |
521 | goto error; |
522 | } | |
523 | stream->out_fd = ret; | |
524 | } | |
525 | ||
526 | if (stream->output == LTTNG_EVENT_MMAP) { | |
527 | /* get the len of the mmap region */ | |
528 | unsigned long mmap_len; | |
529 | ||
530 | ret = kernctl_get_mmap_len(stream->wait_fd, &mmap_len); | |
531 | if (ret != 0) { | |
87dc6a9c | 532 | errno = -ret; |
ffe60014 | 533 | PERROR("kernctl_get_mmap_len"); |
d41f73b7 MD |
534 | goto error_close_fd; |
535 | } | |
536 | stream->mmap_len = (size_t) mmap_len; | |
537 | ||
ffe60014 DG |
538 | stream->mmap_base = mmap(NULL, stream->mmap_len, PROT_READ, |
539 | MAP_PRIVATE, stream->wait_fd, 0); | |
d41f73b7 | 540 | if (stream->mmap_base == MAP_FAILED) { |
ffe60014 | 541 | PERROR("Error mmaping"); |
d41f73b7 MD |
542 | ret = -1; |
543 | goto error_close_fd; | |
544 | } | |
545 | } | |
546 | ||
547 | /* we return 0 to let the library handle the FD internally */ | |
548 | return 0; | |
549 | ||
550 | error_close_fd: | |
551 | { | |
552 | int err; | |
553 | ||
554 | err = close(stream->out_fd); | |
555 | assert(!err); | |
556 | } | |
557 | error: | |
558 | return ret; | |
559 | } | |
560 | ||
ca22feea DG |
561 | /* |
562 | * Check if data is still being extracted from the buffers for a specific | |
4e9a4686 DG |
563 | * stream. Consumer data lock MUST be acquired before calling this function |
564 | * and the stream lock. | |
ca22feea | 565 | * |
6d805429 | 566 | * Return 1 if the traced data are still getting read else 0 meaning that the |
ca22feea DG |
567 | * data is available for trace viewer reading. |
568 | */ | |
6d805429 | 569 | int lttng_kconsumer_data_pending(struct lttng_consumer_stream *stream) |
ca22feea DG |
570 | { |
571 | int ret; | |
572 | ||
573 | assert(stream); | |
574 | ||
ca22feea DG |
575 | ret = kernctl_get_next_subbuf(stream->wait_fd); |
576 | if (ret == 0) { | |
577 | /* There is still data so let's put back this subbuffer. */ | |
578 | ret = kernctl_put_subbuf(stream->wait_fd); | |
579 | assert(ret == 0); | |
6d805429 | 580 | ret = 1; /* Data is pending */ |
4e9a4686 | 581 | goto end; |
ca22feea DG |
582 | } |
583 | ||
6d805429 DG |
584 | /* Data is NOT pending and ready to be read. */ |
585 | ret = 0; | |
ca22feea | 586 | |
6efae65e DG |
587 | end: |
588 | return ret; | |
ca22feea | 589 | } |