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 | ||
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> | |
dbb5dfe6 | 27 | #include <sys/stat.h> |
3bd1e081 MD |
28 | #include <sys/types.h> |
29 | #include <unistd.h> | |
9df8df5e | 30 | #include <lttng/ust-ctl.h> |
0857097f | 31 | |
990570ed | 32 | #include <common/common.h> |
10a8a223 | 33 | #include <common/sessiond-comm/sessiond-comm.h> |
00e2e675 | 34 | #include <common/relayd/relayd.h> |
dbb5dfe6 | 35 | #include <common/compat/fcntl.h> |
10a8a223 DG |
36 | |
37 | #include "ust-consumer.h" | |
3bd1e081 MD |
38 | |
39 | extern struct lttng_consumer_global_data consumer_data; | |
40 | extern int consumer_poll_timeout; | |
41 | extern volatile int consumer_quit; | |
42 | ||
43 | /* | |
44 | * Mmap the ring buffer, read it and write the data to the tracefile. | |
45 | * | |
4078b776 | 46 | * Returns the number of bytes written, else negative value on error. |
3bd1e081 | 47 | */ |
4078b776 | 48 | ssize_t lttng_ustconsumer_on_read_subbuffer_mmap( |
3bd1e081 MD |
49 | struct lttng_consumer_local_data *ctx, |
50 | struct lttng_consumer_stream *stream, unsigned long len) | |
51 | { | |
52 | unsigned long mmap_offset; | |
47e81c02 | 53 | long ret = 0, written = 0; |
3bd1e081 MD |
54 | off_t orig_offset = stream->out_fd_offset; |
55 | int outfd = stream->out_fd; | |
00e2e675 DG |
56 | uint64_t metadata_id; |
57 | struct consumer_relayd_sock_pair *relayd = NULL; | |
58 | ||
59 | /* Flag that the current stream if set for network streaming. */ | |
60 | if (stream->net_seq_idx != -1) { | |
61 | relayd = consumer_find_relayd(stream->net_seq_idx); | |
62 | if (relayd == NULL) { | |
63 | goto end; | |
64 | } | |
65 | } | |
3bd1e081 MD |
66 | |
67 | /* get the offset inside the fd to mmap */ | |
68 | ret = ustctl_get_mmap_read_offset(stream->chan->handle, | |
69 | stream->buf, &mmap_offset); | |
70 | if (ret != 0) { | |
87dc6a9c | 71 | errno = -ret; |
4c462e79 | 72 | PERROR("ustctl_get_mmap_read_offset"); |
47e81c02 | 73 | written = ret; |
3bd1e081 MD |
74 | goto end; |
75 | } | |
00e2e675 DG |
76 | |
77 | /* Handle stream on the relayd if the output is on the network */ | |
78 | if (relayd) { | |
79 | if (stream->metadata_flag) { | |
80 | /* Only lock if metadata since we use the control socket. */ | |
81 | pthread_mutex_lock(&relayd->ctrl_sock_mutex); | |
82 | } | |
83 | ||
84 | ret = consumer_handle_stream_before_relayd(stream, len); | |
85 | if (ret >= 0) { | |
86 | outfd = ret; | |
87 | ||
88 | /* Write metadata stream id before payload */ | |
89 | if (stream->metadata_flag) { | |
90 | metadata_id = htobe64(stream->relayd_stream_id); | |
91 | do { | |
92 | ret = write(outfd, (void *) &metadata_id, | |
93 | sizeof(stream->relayd_stream_id)); | |
94 | if (ret < 0) { | |
95 | PERROR("write metadata stream id"); | |
96 | written = ret; | |
97 | goto end; | |
98 | } | |
99 | } while (errno == EINTR); | |
100 | DBG("Metadata stream id %zu written before data", | |
101 | stream->relayd_stream_id); | |
102 | } | |
103 | } | |
104 | /* Else, use the default set before which is the filesystem. */ | |
105 | } | |
106 | ||
3bd1e081 MD |
107 | while (len > 0) { |
108 | ret = write(outfd, stream->mmap_base + mmap_offset, len); | |
47e81c02 MD |
109 | if (ret < 0) { |
110 | if (errno == EINTR) { | |
111 | /* restart the interrupted system call */ | |
112 | continue; | |
113 | } else { | |
114 | PERROR("Error in file write"); | |
115 | if (written == 0) { | |
116 | written = ret; | |
117 | } | |
118 | goto end; | |
119 | } | |
120 | } else if (ret > len) { | |
00e2e675 | 121 | PERROR("ret %ld > len %lu", ret, len); |
47e81c02 | 122 | written += ret; |
3bd1e081 | 123 | goto end; |
47e81c02 MD |
124 | } else { |
125 | len -= ret; | |
126 | mmap_offset += ret; | |
3bd1e081 | 127 | } |
00e2e675 DG |
128 | DBG("UST mmap write() ret %ld (len %lu)", ret, len); |
129 | ||
130 | /* This call is useless on a socket so better save a syscall. */ | |
131 | if (!relayd) { | |
132 | /* This won't block, but will start writeout asynchronously */ | |
133 | lttng_sync_file_range(outfd, stream->out_fd_offset, ret, | |
134 | SYNC_FILE_RANGE_WRITE); | |
135 | stream->out_fd_offset += ret; | |
136 | } | |
47e81c02 | 137 | written += ret; |
3bd1e081 | 138 | } |
3bd1e081 | 139 | lttng_consumer_sync_trace_file(stream, orig_offset); |
00e2e675 | 140 | |
3bd1e081 | 141 | end: |
00e2e675 DG |
142 | if (relayd && stream->metadata_flag) { |
143 | pthread_mutex_unlock(&relayd->ctrl_sock_mutex); | |
144 | } | |
47e81c02 | 145 | return written; |
3bd1e081 MD |
146 | } |
147 | ||
148 | /* | |
149 | * Splice the data from the ring buffer to the tracefile. | |
150 | * | |
151 | * Returns the number of bytes spliced. | |
152 | */ | |
4078b776 | 153 | ssize_t lttng_ustconsumer_on_read_subbuffer_splice( |
3bd1e081 MD |
154 | struct lttng_consumer_local_data *ctx, |
155 | struct lttng_consumer_stream *stream, unsigned long len) | |
156 | { | |
157 | return -ENOSYS; | |
158 | } | |
159 | ||
160 | /* | |
161 | * Take a snapshot for a specific fd | |
162 | * | |
163 | * Returns 0 on success, < 0 on error | |
164 | */ | |
165 | int lttng_ustconsumer_take_snapshot(struct lttng_consumer_local_data *ctx, | |
166 | struct lttng_consumer_stream *stream) | |
167 | { | |
168 | int ret = 0; | |
169 | ||
170 | ret = ustctl_snapshot(stream->chan->handle, stream->buf); | |
171 | if (ret != 0) { | |
87dc6a9c | 172 | errno = -ret; |
4c462e79 | 173 | PERROR("Getting sub-buffer snapshot."); |
3bd1e081 MD |
174 | } |
175 | ||
176 | return ret; | |
177 | } | |
178 | ||
179 | /* | |
180 | * Get the produced position | |
181 | * | |
182 | * Returns 0 on success, < 0 on error | |
183 | */ | |
184 | int lttng_ustconsumer_get_produced_snapshot( | |
185 | struct lttng_consumer_local_data *ctx, | |
186 | struct lttng_consumer_stream *stream, | |
187 | unsigned long *pos) | |
188 | { | |
189 | int ret; | |
190 | ||
191 | ret = ustctl_snapshot_get_produced(stream->chan->handle, | |
192 | stream->buf, pos); | |
193 | if (ret != 0) { | |
87dc6a9c | 194 | errno = -ret; |
4c462e79 | 195 | PERROR("kernctl_snapshot_get_produced"); |
3bd1e081 MD |
196 | } |
197 | ||
198 | return ret; | |
199 | } | |
200 | ||
201 | int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data *ctx, | |
202 | int sock, struct pollfd *consumer_sockpoll) | |
203 | { | |
204 | ssize_t ret; | |
205 | struct lttcomm_consumer_msg msg; | |
206 | ||
207 | ret = lttcomm_recv_unix_sock(sock, &msg, sizeof(msg)); | |
208 | if (ret != sizeof(msg)) { | |
209 | lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD); | |
210 | return ret; | |
211 | } | |
212 | if (msg.cmd_type == LTTNG_CONSUMER_STOP) { | |
213 | return -ENOENT; | |
214 | } | |
215 | ||
216 | switch (msg.cmd_type) { | |
00e2e675 DG |
217 | case LTTNG_CONSUMER_ADD_RELAYD_SOCKET: |
218 | { | |
219 | int fd; | |
220 | struct consumer_relayd_sock_pair *relayd; | |
221 | ||
222 | DBG("UST Consumer adding relayd socket"); | |
223 | ||
224 | /* Get relayd reference if exists. */ | |
225 | relayd = consumer_find_relayd(msg.u.relayd_sock.net_index); | |
226 | if (relayd == NULL) { | |
227 | /* Not found. Allocate one. */ | |
228 | relayd = consumer_allocate_relayd_sock_pair( | |
229 | msg.u.relayd_sock.net_index); | |
230 | if (relayd == NULL) { | |
231 | lttng_consumer_send_error(ctx, CONSUMERD_OUTFD_ERROR); | |
232 | goto end_nosignal; | |
233 | } | |
234 | } | |
235 | ||
236 | /* Poll on consumer socket. */ | |
237 | if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) { | |
238 | return -EINTR; | |
239 | } | |
240 | ||
241 | /* Get relayd socket from session daemon */ | |
242 | ret = lttcomm_recv_fds_unix_sock(sock, &fd, 1); | |
243 | if (ret != sizeof(fd)) { | |
244 | lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD); | |
245 | goto end_nosignal; | |
246 | } | |
247 | ||
248 | /* Copy socket information and received FD */ | |
249 | switch (msg.u.relayd_sock.type) { | |
250 | case LTTNG_STREAM_CONTROL: | |
251 | /* Copy received lttcomm socket */ | |
252 | lttcomm_copy_sock(&relayd->control_sock, &msg.u.relayd_sock.sock); | |
253 | ret = lttcomm_create_sock(&relayd->control_sock); | |
254 | if (ret < 0) { | |
255 | goto end_nosignal; | |
256 | } | |
257 | ||
258 | /* Close the created socket fd which is useless */ | |
259 | close(relayd->control_sock.fd); | |
260 | ||
261 | /* Assign new file descriptor */ | |
262 | relayd->control_sock.fd = fd; | |
263 | break; | |
264 | case LTTNG_STREAM_DATA: | |
265 | /* Copy received lttcomm socket */ | |
266 | lttcomm_copy_sock(&relayd->data_sock, &msg.u.relayd_sock.sock); | |
267 | ret = lttcomm_create_sock(&relayd->data_sock); | |
268 | if (ret < 0) { | |
269 | goto end_nosignal; | |
270 | } | |
271 | ||
272 | /* Close the created socket fd which is useless */ | |
273 | close(relayd->data_sock.fd); | |
274 | ||
275 | /* Assign new file descriptor */ | |
276 | relayd->data_sock.fd = fd; | |
277 | break; | |
278 | default: | |
279 | ERR("Unknown relayd socket type"); | |
280 | goto end_nosignal; | |
281 | } | |
282 | ||
283 | DBG("Consumer %s socket created successfully with net idx %d (fd: %d)", | |
284 | msg.u.relayd_sock.type == LTTNG_STREAM_CONTROL ? "control" : "data", | |
285 | relayd->net_seq_idx, fd); | |
286 | ||
287 | /* | |
288 | * Add relayd socket pair to consumer data hashtable. If object already | |
289 | * exists or on error, the function gracefully returns. | |
290 | */ | |
291 | consumer_add_relayd(relayd); | |
292 | ||
293 | goto end_nosignal; | |
294 | } | |
3bd1e081 MD |
295 | case LTTNG_CONSUMER_ADD_CHANNEL: |
296 | { | |
297 | struct lttng_consumer_channel *new_channel; | |
298 | int fds[1]; | |
299 | size_t nb_fd = 1; | |
300 | ||
301 | /* block */ | |
302 | if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) { | |
303 | return -EINTR; | |
304 | } | |
305 | ret = lttcomm_recv_fds_unix_sock(sock, fds, nb_fd); | |
306 | if (ret != sizeof(fds)) { | |
307 | lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD); | |
308 | return ret; | |
309 | } | |
310 | ||
311 | DBG("consumer_add_channel %d", msg.u.channel.channel_key); | |
312 | ||
313 | new_channel = consumer_allocate_channel(msg.u.channel.channel_key, | |
314 | fds[0], -1, | |
315 | msg.u.channel.mmap_len, | |
316 | msg.u.channel.max_sb_size); | |
317 | if (new_channel == NULL) { | |
318 | lttng_consumer_send_error(ctx, CONSUMERD_OUTFD_ERROR); | |
319 | goto end_nosignal; | |
320 | } | |
321 | if (ctx->on_recv_channel != NULL) { | |
322 | ret = ctx->on_recv_channel(new_channel); | |
323 | if (ret == 0) { | |
324 | consumer_add_channel(new_channel); | |
325 | } else if (ret < 0) { | |
326 | goto end_nosignal; | |
327 | } | |
328 | } else { | |
329 | consumer_add_channel(new_channel); | |
330 | } | |
331 | goto end_nosignal; | |
332 | } | |
333 | case LTTNG_CONSUMER_ADD_STREAM: | |
334 | { | |
335 | struct lttng_consumer_stream *new_stream; | |
336 | int fds[2]; | |
337 | size_t nb_fd = 2; | |
00e2e675 | 338 | struct consumer_relayd_sock_pair *relayd = NULL; |
3bd1e081 MD |
339 | |
340 | /* block */ | |
341 | if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) { | |
342 | return -EINTR; | |
343 | } | |
344 | ret = lttcomm_recv_fds_unix_sock(sock, fds, nb_fd); | |
345 | if (ret != sizeof(fds)) { | |
346 | lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD); | |
347 | return ret; | |
348 | } | |
349 | ||
d41f73b7 | 350 | assert(msg.u.stream.output == LTTNG_EVENT_MMAP); |
7ad0a0cb | 351 | new_stream = consumer_allocate_stream(msg.u.channel.channel_key, |
3bd1e081 MD |
352 | msg.u.stream.stream_key, |
353 | fds[0], fds[1], | |
354 | msg.u.stream.state, | |
355 | msg.u.stream.mmap_len, | |
356 | msg.u.stream.output, | |
6df2e2c9 MD |
357 | msg.u.stream.path_name, |
358 | msg.u.stream.uid, | |
00e2e675 DG |
359 | msg.u.stream.gid, |
360 | msg.u.stream.net_index, | |
361 | msg.u.stream.metadata_flag); | |
3bd1e081 MD |
362 | if (new_stream == NULL) { |
363 | lttng_consumer_send_error(ctx, CONSUMERD_OUTFD_ERROR); | |
364 | goto end; | |
365 | } | |
00e2e675 DG |
366 | |
367 | /* The stream is not metadata. Get relayd reference if exists. */ | |
368 | relayd = consumer_find_relayd(msg.u.stream.net_index); | |
369 | if (relayd != NULL) { | |
370 | pthread_mutex_lock(&relayd->ctrl_sock_mutex); | |
371 | /* Add stream on the relayd */ | |
372 | ret = relayd_add_stream(&relayd->control_sock, | |
373 | msg.u.stream.name, msg.u.stream.path_name, | |
374 | &new_stream->relayd_stream_id); | |
375 | pthread_mutex_unlock(&relayd->ctrl_sock_mutex); | |
376 | if (ret < 0) { | |
377 | goto end; | |
378 | } | |
379 | } else if (msg.u.stream.net_index != -1) { | |
380 | ERR("Network sequence index %d unknown. Not adding stream.", | |
381 | msg.u.stream.net_index); | |
382 | free(new_stream); | |
383 | goto end; | |
384 | } | |
385 | ||
3bd1e081 MD |
386 | if (ctx->on_recv_stream != NULL) { |
387 | ret = ctx->on_recv_stream(new_stream); | |
388 | if (ret == 0) { | |
389 | consumer_add_stream(new_stream); | |
390 | } else if (ret < 0) { | |
391 | goto end; | |
392 | } | |
393 | } else { | |
394 | consumer_add_stream(new_stream); | |
395 | } | |
00e2e675 DG |
396 | |
397 | DBG("UST consumer_add_stream %s (%d,%d) with relayd id %lu", | |
398 | msg.u.stream.path_name, fds[0], fds[1], | |
399 | new_stream->relayd_stream_id); | |
3bd1e081 MD |
400 | break; |
401 | } | |
402 | case LTTNG_CONSUMER_UPDATE_STREAM: | |
403 | { | |
7ad0a0cb MD |
404 | return -ENOSYS; |
405 | #if 0 | |
3bd1e081 MD |
406 | if (ctx->on_update_stream != NULL) { |
407 | ret = ctx->on_update_stream(msg.u.stream.stream_key, msg.u.stream.state); | |
408 | if (ret == 0) { | |
409 | consumer_change_stream_state(msg.u.stream.stream_key, msg.u.stream.state); | |
410 | } else if (ret < 0) { | |
411 | goto end; | |
412 | } | |
413 | } else { | |
414 | consumer_change_stream_state(msg.u.stream.stream_key, | |
415 | msg.u.stream.state); | |
416 | } | |
7ad0a0cb | 417 | #endif |
3bd1e081 MD |
418 | break; |
419 | } | |
420 | default: | |
421 | break; | |
422 | } | |
423 | end: | |
04fdd819 MD |
424 | /* |
425 | * Wake-up the other end by writing a null byte in the pipe | |
426 | * (non-blocking). Important note: Because writing into the | |
427 | * pipe is non-blocking (and therefore we allow dropping wakeup | |
428 | * data, as long as there is wakeup data present in the pipe | |
429 | * buffer to wake up the other end), the other end should | |
430 | * perform the following sequence for waiting: | |
431 | * 1) empty the pipe (reads). | |
432 | * 2) perform update operation. | |
433 | * 3) wait on the pipe (poll). | |
434 | */ | |
435 | do { | |
436 | ret = write(ctx->consumer_poll_pipe[1], "", 1); | |
437 | } while (ret == -1UL && errno == EINTR); | |
3bd1e081 MD |
438 | end_nosignal: |
439 | return 0; | |
440 | } | |
441 | ||
442 | int lttng_ustconsumer_allocate_channel(struct lttng_consumer_channel *chan) | |
443 | { | |
13161846 | 444 | struct lttng_ust_object_data obj; |
3bd1e081 MD |
445 | |
446 | obj.handle = -1; | |
447 | obj.shm_fd = chan->shm_fd; | |
448 | obj.wait_fd = chan->wait_fd; | |
449 | obj.memory_map_size = chan->mmap_len; | |
450 | chan->handle = ustctl_map_channel(&obj); | |
451 | if (!chan->handle) { | |
452 | return -ENOMEM; | |
453 | } | |
b5c5fc29 | 454 | chan->wait_fd_is_copy = 1; |
2c1dd183 | 455 | chan->shm_fd = -1; |
b5c5fc29 | 456 | |
3bd1e081 MD |
457 | return 0; |
458 | } | |
459 | ||
d056b477 MD |
460 | void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream *stream) |
461 | { | |
462 | ustctl_flush_buffer(stream->chan->handle, stream->buf, 0); | |
effcf122 | 463 | stream->hangup_flush_done = 1; |
d056b477 MD |
464 | } |
465 | ||
3bd1e081 MD |
466 | void lttng_ustconsumer_del_channel(struct lttng_consumer_channel *chan) |
467 | { | |
468 | ustctl_unmap_channel(chan->handle); | |
469 | } | |
470 | ||
471 | int lttng_ustconsumer_allocate_stream(struct lttng_consumer_stream *stream) | |
472 | { | |
13161846 | 473 | struct lttng_ust_object_data obj; |
3bd1e081 MD |
474 | int ret; |
475 | ||
476 | obj.handle = -1; | |
477 | obj.shm_fd = stream->shm_fd; | |
478 | obj.wait_fd = stream->wait_fd; | |
479 | obj.memory_map_size = stream->mmap_len; | |
480 | ret = ustctl_add_stream(stream->chan->handle, &obj); | |
481 | if (ret) | |
482 | return ret; | |
483 | stream->buf = ustctl_open_stream_read(stream->chan->handle, stream->cpu); | |
484 | if (!stream->buf) | |
485 | return -EBUSY; | |
2c1dd183 MD |
486 | /* ustctl_open_stream_read has closed the shm fd. */ |
487 | stream->wait_fd_is_copy = 1; | |
488 | stream->shm_fd = -1; | |
489 | ||
3bd1e081 MD |
490 | stream->mmap_base = ustctl_get_mmap_base(stream->chan->handle, stream->buf); |
491 | if (!stream->mmap_base) { | |
492 | return -EINVAL; | |
493 | } | |
ee77a7b0 | 494 | |
3bd1e081 MD |
495 | return 0; |
496 | } | |
497 | ||
498 | void lttng_ustconsumer_del_stream(struct lttng_consumer_stream *stream) | |
499 | { | |
500 | ustctl_close_stream_read(stream->chan->handle, stream->buf); | |
501 | } | |
d41f73b7 MD |
502 | |
503 | ||
504 | int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream *stream, | |
505 | struct lttng_consumer_local_data *ctx) | |
506 | { | |
507 | unsigned long len; | |
508 | int err; | |
509 | long ret = 0; | |
510 | struct lttng_ust_shm_handle *handle; | |
511 | struct lttng_ust_lib_ring_buffer *buf; | |
512 | char dummy; | |
513 | ssize_t readlen; | |
514 | ||
515 | DBG("In read_subbuffer (wait_fd: %d, stream key: %d)", | |
516 | stream->wait_fd, stream->key); | |
517 | ||
518 | /* We can consume the 1 byte written into the wait_fd by UST */ | |
effcf122 MD |
519 | if (!stream->hangup_flush_done) { |
520 | do { | |
521 | readlen = read(stream->wait_fd, &dummy, 1); | |
87dc6a9c | 522 | } while (readlen == -1 && errno == EINTR); |
effcf122 MD |
523 | if (readlen == -1) { |
524 | ret = readlen; | |
525 | goto end; | |
526 | } | |
d41f73b7 MD |
527 | } |
528 | ||
529 | buf = stream->buf; | |
530 | handle = stream->chan->handle; | |
531 | /* Get the next subbuffer */ | |
532 | err = ustctl_get_next_subbuf(handle, buf); | |
533 | if (err != 0) { | |
effcf122 | 534 | ret = -ret; /* ustctl_get_next_subbuf returns negative, caller expect positive. */ |
d41f73b7 MD |
535 | /* |
536 | * This is a debug message even for single-threaded consumer, | |
537 | * because poll() have more relaxed criterions than get subbuf, | |
538 | * so get_subbuf may fail for short race windows where poll() | |
539 | * would issue wakeups. | |
540 | */ | |
541 | DBG("Reserving sub buffer failed (everything is normal, " | |
542 | "it is due to concurrency)"); | |
543 | goto end; | |
544 | } | |
545 | assert(stream->output == LTTNG_EVENT_MMAP); | |
546 | /* read the used subbuffer size */ | |
547 | err = ustctl_get_padded_subbuf_size(handle, buf, &len); | |
effcf122 | 548 | assert(err == 0); |
d41f73b7 MD |
549 | /* write the subbuffer to the tracefile */ |
550 | ret = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, len); | |
47e81c02 | 551 | if (ret != len) { |
d41f73b7 MD |
552 | /* |
553 | * display the error but continue processing to try | |
554 | * to release the subbuffer | |
555 | */ | |
556 | ERR("Error writing to tracefile"); | |
557 | } | |
558 | err = ustctl_put_next_subbuf(handle, buf); | |
effcf122 | 559 | assert(err == 0); |
d41f73b7 MD |
560 | end: |
561 | return ret; | |
562 | } | |
563 | ||
564 | int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream *stream) | |
565 | { | |
566 | int ret; | |
567 | ||
568 | /* Opening the tracefile in write mode */ | |
00e2e675 | 569 | if (stream->path_name != NULL && stream->net_seq_idx == -1) { |
e11d277b | 570 | ret = run_as_open(stream->path_name, |
60b6c79c MD |
571 | O_WRONLY|O_CREAT|O_TRUNC, |
572 | S_IRWXU|S_IRWXG|S_IRWXO, | |
573 | stream->uid, stream->gid); | |
d41f73b7 MD |
574 | if (ret < 0) { |
575 | ERR("Opening %s", stream->path_name); | |
4c462e79 | 576 | PERROR("open"); |
d41f73b7 MD |
577 | goto error; |
578 | } | |
579 | stream->out_fd = ret; | |
580 | } | |
581 | ||
582 | /* we return 0 to let the library handle the FD internally */ | |
583 | return 0; | |
584 | ||
585 | error: | |
586 | return ret; | |
587 | } |