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> | |
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 | ||
b0b335c8 MD |
59 | /* RCU lock for the relayd pointer */ |
60 | rcu_read_lock(); | |
61 | ||
00e2e675 DG |
62 | /* Flag that the current stream if set for network streaming. */ |
63 | if (stream->net_seq_idx != -1) { | |
64 | relayd = consumer_find_relayd(stream->net_seq_idx); | |
65 | if (relayd == NULL) { | |
87c1611d DG |
66 | ERR("UST consumer mmap(), unable to find relay for index %d", |
67 | stream->net_seq_idx); | |
00e2e675 DG |
68 | goto end; |
69 | } | |
70 | } | |
3bd1e081 MD |
71 | |
72 | /* get the offset inside the fd to mmap */ | |
73 | ret = ustctl_get_mmap_read_offset(stream->chan->handle, | |
74 | stream->buf, &mmap_offset); | |
75 | if (ret != 0) { | |
87dc6a9c | 76 | errno = -ret; |
4c462e79 | 77 | PERROR("ustctl_get_mmap_read_offset"); |
47e81c02 | 78 | written = ret; |
3bd1e081 MD |
79 | goto end; |
80 | } | |
00e2e675 DG |
81 | |
82 | /* Handle stream on the relayd if the output is on the network */ | |
83 | if (relayd) { | |
f6416125 MD |
84 | unsigned long netlen = len; |
85 | ||
00e2e675 DG |
86 | if (stream->metadata_flag) { |
87 | /* Only lock if metadata since we use the control socket. */ | |
88 | pthread_mutex_lock(&relayd->ctrl_sock_mutex); | |
f6416125 | 89 | netlen += sizeof(stream->relayd_stream_id); |
00e2e675 DG |
90 | } |
91 | ||
f6416125 | 92 | ret = consumer_handle_stream_before_relayd(stream, netlen); |
00e2e675 DG |
93 | if (ret >= 0) { |
94 | outfd = ret; | |
95 | ||
96 | /* Write metadata stream id before payload */ | |
97 | if (stream->metadata_flag) { | |
98 | metadata_id = htobe64(stream->relayd_stream_id); | |
99 | do { | |
100 | ret = write(outfd, (void *) &metadata_id, | |
101 | sizeof(stream->relayd_stream_id)); | |
6f94560a MD |
102 | } while (ret < 0 && errno == EINTR); |
103 | if (ret < 0) { | |
104 | PERROR("write metadata stream id"); | |
105 | written = ret; | |
106 | goto end; | |
107 | } | |
00e2e675 DG |
108 | DBG("Metadata stream id %zu written before data", |
109 | stream->relayd_stream_id); | |
110 | } | |
111 | } | |
112 | /* Else, use the default set before which is the filesystem. */ | |
113 | } | |
114 | ||
3bd1e081 | 115 | while (len > 0) { |
6f94560a MD |
116 | do { |
117 | ret = write(outfd, stream->mmap_base + mmap_offset, len); | |
118 | } while (ret < 0 && errno == EINTR); | |
47e81c02 | 119 | if (ret < 0) { |
6f94560a MD |
120 | PERROR("Error in file write"); |
121 | if (written == 0) { | |
122 | written = ret; | |
47e81c02 | 123 | } |
6f94560a | 124 | goto end; |
47e81c02 | 125 | } else if (ret > len) { |
00e2e675 | 126 | PERROR("ret %ld > len %lu", ret, len); |
47e81c02 | 127 | written += ret; |
3bd1e081 | 128 | goto end; |
47e81c02 MD |
129 | } else { |
130 | len -= ret; | |
131 | mmap_offset += ret; | |
3bd1e081 | 132 | } |
00e2e675 DG |
133 | DBG("UST mmap write() ret %ld (len %lu)", ret, len); |
134 | ||
135 | /* This call is useless on a socket so better save a syscall. */ | |
136 | if (!relayd) { | |
137 | /* This won't block, but will start writeout asynchronously */ | |
138 | lttng_sync_file_range(outfd, stream->out_fd_offset, ret, | |
139 | SYNC_FILE_RANGE_WRITE); | |
140 | stream->out_fd_offset += ret; | |
141 | } | |
47e81c02 | 142 | written += ret; |
3bd1e081 | 143 | } |
3bd1e081 | 144 | lttng_consumer_sync_trace_file(stream, orig_offset); |
00e2e675 | 145 | |
3bd1e081 | 146 | end: |
00e2e675 DG |
147 | if (relayd && stream->metadata_flag) { |
148 | pthread_mutex_unlock(&relayd->ctrl_sock_mutex); | |
149 | } | |
b0b335c8 | 150 | rcu_read_unlock(); |
47e81c02 | 151 | return written; |
3bd1e081 MD |
152 | } |
153 | ||
154 | /* | |
155 | * Splice the data from the ring buffer to the tracefile. | |
156 | * | |
157 | * Returns the number of bytes spliced. | |
158 | */ | |
4078b776 | 159 | ssize_t lttng_ustconsumer_on_read_subbuffer_splice( |
3bd1e081 MD |
160 | struct lttng_consumer_local_data *ctx, |
161 | struct lttng_consumer_stream *stream, unsigned long len) | |
162 | { | |
163 | return -ENOSYS; | |
164 | } | |
165 | ||
166 | /* | |
167 | * Take a snapshot for a specific fd | |
168 | * | |
169 | * Returns 0 on success, < 0 on error | |
170 | */ | |
171 | int lttng_ustconsumer_take_snapshot(struct lttng_consumer_local_data *ctx, | |
172 | struct lttng_consumer_stream *stream) | |
173 | { | |
174 | int ret = 0; | |
175 | ||
176 | ret = ustctl_snapshot(stream->chan->handle, stream->buf); | |
177 | if (ret != 0) { | |
87dc6a9c | 178 | errno = -ret; |
4c462e79 | 179 | PERROR("Getting sub-buffer snapshot."); |
3bd1e081 MD |
180 | } |
181 | ||
182 | return ret; | |
183 | } | |
184 | ||
185 | /* | |
186 | * Get the produced position | |
187 | * | |
188 | * Returns 0 on success, < 0 on error | |
189 | */ | |
190 | int lttng_ustconsumer_get_produced_snapshot( | |
191 | struct lttng_consumer_local_data *ctx, | |
192 | struct lttng_consumer_stream *stream, | |
193 | unsigned long *pos) | |
194 | { | |
195 | int ret; | |
196 | ||
197 | ret = ustctl_snapshot_get_produced(stream->chan->handle, | |
198 | stream->buf, pos); | |
199 | if (ret != 0) { | |
87dc6a9c | 200 | errno = -ret; |
4c462e79 | 201 | PERROR("kernctl_snapshot_get_produced"); |
3bd1e081 MD |
202 | } |
203 | ||
204 | return ret; | |
205 | } | |
206 | ||
207 | int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data *ctx, | |
208 | int sock, struct pollfd *consumer_sockpoll) | |
209 | { | |
210 | ssize_t ret; | |
211 | struct lttcomm_consumer_msg msg; | |
212 | ||
213 | ret = lttcomm_recv_unix_sock(sock, &msg, sizeof(msg)); | |
214 | if (ret != sizeof(msg)) { | |
173af62f DG |
215 | DBG("Consumer received unexpected message size %zd (expects %zu)", |
216 | ret, sizeof(msg)); | |
3bd1e081 MD |
217 | lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD); |
218 | return ret; | |
219 | } | |
220 | if (msg.cmd_type == LTTNG_CONSUMER_STOP) { | |
221 | return -ENOENT; | |
222 | } | |
223 | ||
b0b335c8 MD |
224 | /* relayd need RCU read-side lock */ |
225 | rcu_read_lock(); | |
226 | ||
3bd1e081 | 227 | switch (msg.cmd_type) { |
00e2e675 DG |
228 | case LTTNG_CONSUMER_ADD_RELAYD_SOCKET: |
229 | { | |
230 | int fd; | |
231 | struct consumer_relayd_sock_pair *relayd; | |
232 | ||
233 | DBG("UST Consumer adding relayd socket"); | |
234 | ||
235 | /* Get relayd reference if exists. */ | |
236 | relayd = consumer_find_relayd(msg.u.relayd_sock.net_index); | |
237 | if (relayd == NULL) { | |
238 | /* Not found. Allocate one. */ | |
239 | relayd = consumer_allocate_relayd_sock_pair( | |
240 | msg.u.relayd_sock.net_index); | |
241 | if (relayd == NULL) { | |
242 | lttng_consumer_send_error(ctx, CONSUMERD_OUTFD_ERROR); | |
243 | goto end_nosignal; | |
244 | } | |
245 | } | |
246 | ||
247 | /* Poll on consumer socket. */ | |
248 | if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) { | |
249 | return -EINTR; | |
250 | } | |
251 | ||
252 | /* Get relayd socket from session daemon */ | |
253 | ret = lttcomm_recv_fds_unix_sock(sock, &fd, 1); | |
254 | if (ret != sizeof(fd)) { | |
255 | lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD); | |
256 | goto end_nosignal; | |
257 | } | |
258 | ||
259 | /* Copy socket information and received FD */ | |
260 | switch (msg.u.relayd_sock.type) { | |
261 | case LTTNG_STREAM_CONTROL: | |
262 | /* Copy received lttcomm socket */ | |
263 | lttcomm_copy_sock(&relayd->control_sock, &msg.u.relayd_sock.sock); | |
264 | ret = lttcomm_create_sock(&relayd->control_sock); | |
265 | if (ret < 0) { | |
266 | goto end_nosignal; | |
267 | } | |
268 | ||
269 | /* Close the created socket fd which is useless */ | |
270 | close(relayd->control_sock.fd); | |
271 | ||
272 | /* Assign new file descriptor */ | |
273 | relayd->control_sock.fd = fd; | |
274 | break; | |
275 | case LTTNG_STREAM_DATA: | |
276 | /* Copy received lttcomm socket */ | |
277 | lttcomm_copy_sock(&relayd->data_sock, &msg.u.relayd_sock.sock); | |
278 | ret = lttcomm_create_sock(&relayd->data_sock); | |
279 | if (ret < 0) { | |
280 | goto end_nosignal; | |
281 | } | |
282 | ||
283 | /* Close the created socket fd which is useless */ | |
284 | close(relayd->data_sock.fd); | |
285 | ||
286 | /* Assign new file descriptor */ | |
287 | relayd->data_sock.fd = fd; | |
288 | break; | |
289 | default: | |
290 | ERR("Unknown relayd socket type"); | |
291 | goto end_nosignal; | |
292 | } | |
293 | ||
294 | DBG("Consumer %s socket created successfully with net idx %d (fd: %d)", | |
295 | msg.u.relayd_sock.type == LTTNG_STREAM_CONTROL ? "control" : "data", | |
296 | relayd->net_seq_idx, fd); | |
297 | ||
298 | /* | |
299 | * Add relayd socket pair to consumer data hashtable. If object already | |
300 | * exists or on error, the function gracefully returns. | |
301 | */ | |
302 | consumer_add_relayd(relayd); | |
303 | ||
304 | goto end_nosignal; | |
305 | } | |
3bd1e081 MD |
306 | case LTTNG_CONSUMER_ADD_CHANNEL: |
307 | { | |
308 | struct lttng_consumer_channel *new_channel; | |
309 | int fds[1]; | |
310 | size_t nb_fd = 1; | |
311 | ||
173af62f DG |
312 | DBG("UST Consumer adding channel"); |
313 | ||
3bd1e081 MD |
314 | /* block */ |
315 | if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) { | |
316 | return -EINTR; | |
317 | } | |
318 | ret = lttcomm_recv_fds_unix_sock(sock, fds, nb_fd); | |
319 | if (ret != sizeof(fds)) { | |
320 | lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD); | |
321 | return ret; | |
322 | } | |
323 | ||
324 | DBG("consumer_add_channel %d", msg.u.channel.channel_key); | |
325 | ||
326 | new_channel = consumer_allocate_channel(msg.u.channel.channel_key, | |
327 | fds[0], -1, | |
328 | msg.u.channel.mmap_len, | |
329 | msg.u.channel.max_sb_size); | |
330 | if (new_channel == NULL) { | |
331 | lttng_consumer_send_error(ctx, CONSUMERD_OUTFD_ERROR); | |
332 | goto end_nosignal; | |
333 | } | |
334 | if (ctx->on_recv_channel != NULL) { | |
335 | ret = ctx->on_recv_channel(new_channel); | |
336 | if (ret == 0) { | |
337 | consumer_add_channel(new_channel); | |
338 | } else if (ret < 0) { | |
339 | goto end_nosignal; | |
340 | } | |
341 | } else { | |
342 | consumer_add_channel(new_channel); | |
343 | } | |
344 | goto end_nosignal; | |
345 | } | |
346 | case LTTNG_CONSUMER_ADD_STREAM: | |
347 | { | |
348 | struct lttng_consumer_stream *new_stream; | |
349 | int fds[2]; | |
350 | size_t nb_fd = 2; | |
00e2e675 | 351 | struct consumer_relayd_sock_pair *relayd = NULL; |
3bd1e081 | 352 | |
173af62f DG |
353 | DBG("UST Consumer adding stream"); |
354 | ||
3bd1e081 MD |
355 | /* block */ |
356 | if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) { | |
357 | return -EINTR; | |
358 | } | |
359 | ret = lttcomm_recv_fds_unix_sock(sock, fds, nb_fd); | |
360 | if (ret != sizeof(fds)) { | |
361 | lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD); | |
362 | return ret; | |
363 | } | |
364 | ||
173af62f DG |
365 | DBG("consumer_add_stream chan %d stream %d", |
366 | msg.u.stream.channel_key, | |
367 | msg.u.stream.stream_key); | |
368 | ||
d41f73b7 | 369 | assert(msg.u.stream.output == LTTNG_EVENT_MMAP); |
173af62f | 370 | new_stream = consumer_allocate_stream(msg.u.stream.channel_key, |
3bd1e081 MD |
371 | msg.u.stream.stream_key, |
372 | fds[0], fds[1], | |
373 | msg.u.stream.state, | |
374 | msg.u.stream.mmap_len, | |
375 | msg.u.stream.output, | |
6df2e2c9 MD |
376 | msg.u.stream.path_name, |
377 | msg.u.stream.uid, | |
00e2e675 DG |
378 | msg.u.stream.gid, |
379 | msg.u.stream.net_index, | |
380 | msg.u.stream.metadata_flag); | |
3bd1e081 MD |
381 | if (new_stream == NULL) { |
382 | lttng_consumer_send_error(ctx, CONSUMERD_OUTFD_ERROR); | |
383 | goto end; | |
384 | } | |
00e2e675 DG |
385 | |
386 | /* The stream is not metadata. Get relayd reference if exists. */ | |
387 | relayd = consumer_find_relayd(msg.u.stream.net_index); | |
388 | if (relayd != NULL) { | |
389 | pthread_mutex_lock(&relayd->ctrl_sock_mutex); | |
390 | /* Add stream on the relayd */ | |
391 | ret = relayd_add_stream(&relayd->control_sock, | |
392 | msg.u.stream.name, msg.u.stream.path_name, | |
393 | &new_stream->relayd_stream_id); | |
394 | pthread_mutex_unlock(&relayd->ctrl_sock_mutex); | |
395 | if (ret < 0) { | |
396 | goto end; | |
397 | } | |
398 | } else if (msg.u.stream.net_index != -1) { | |
399 | ERR("Network sequence index %d unknown. Not adding stream.", | |
400 | msg.u.stream.net_index); | |
401 | free(new_stream); | |
402 | goto end; | |
403 | } | |
404 | ||
3bd1e081 MD |
405 | if (ctx->on_recv_stream != NULL) { |
406 | ret = ctx->on_recv_stream(new_stream); | |
407 | if (ret == 0) { | |
408 | consumer_add_stream(new_stream); | |
409 | } else if (ret < 0) { | |
410 | goto end; | |
411 | } | |
412 | } else { | |
413 | consumer_add_stream(new_stream); | |
414 | } | |
00e2e675 DG |
415 | |
416 | DBG("UST consumer_add_stream %s (%d,%d) with relayd id %lu", | |
417 | msg.u.stream.path_name, fds[0], fds[1], | |
418 | new_stream->relayd_stream_id); | |
3bd1e081 MD |
419 | break; |
420 | } | |
173af62f DG |
421 | case LTTNG_CONSUMER_DESTROY_RELAYD: |
422 | { | |
423 | struct consumer_relayd_sock_pair *relayd; | |
424 | ||
425 | DBG("UST consumer destroying relayd %zu", | |
426 | msg.u.destroy_relayd.net_seq_idx); | |
427 | ||
428 | /* Get relayd reference if exists. */ | |
429 | relayd = consumer_find_relayd(msg.u.destroy_relayd.net_seq_idx); | |
430 | if (relayd == NULL) { | |
431 | ERR("Unable to find relayd %zu", | |
432 | msg.u.destroy_relayd.net_seq_idx); | |
433 | } | |
434 | ||
435 | /* Set destroy flag for this object */ | |
436 | uatomic_set(&relayd->destroy_flag, 1); | |
437 | ||
438 | /* Destroy the relayd if refcount is 0 else set the destroy flag. */ | |
439 | if (uatomic_read(&relayd->refcount) == 0) { | |
440 | consumer_destroy_relayd(relayd); | |
441 | } | |
442 | break; | |
443 | } | |
3bd1e081 MD |
444 | case LTTNG_CONSUMER_UPDATE_STREAM: |
445 | { | |
7ad0a0cb MD |
446 | return -ENOSYS; |
447 | #if 0 | |
3bd1e081 MD |
448 | if (ctx->on_update_stream != NULL) { |
449 | ret = ctx->on_update_stream(msg.u.stream.stream_key, msg.u.stream.state); | |
450 | if (ret == 0) { | |
451 | consumer_change_stream_state(msg.u.stream.stream_key, msg.u.stream.state); | |
452 | } else if (ret < 0) { | |
453 | goto end; | |
454 | } | |
455 | } else { | |
456 | consumer_change_stream_state(msg.u.stream.stream_key, | |
457 | msg.u.stream.state); | |
458 | } | |
7ad0a0cb | 459 | #endif |
3bd1e081 MD |
460 | break; |
461 | } | |
462 | default: | |
463 | break; | |
464 | } | |
465 | end: | |
04fdd819 MD |
466 | /* |
467 | * Wake-up the other end by writing a null byte in the pipe | |
468 | * (non-blocking). Important note: Because writing into the | |
469 | * pipe is non-blocking (and therefore we allow dropping wakeup | |
470 | * data, as long as there is wakeup data present in the pipe | |
471 | * buffer to wake up the other end), the other end should | |
472 | * perform the following sequence for waiting: | |
473 | * 1) empty the pipe (reads). | |
474 | * 2) perform update operation. | |
475 | * 3) wait on the pipe (poll). | |
476 | */ | |
477 | do { | |
478 | ret = write(ctx->consumer_poll_pipe[1], "", 1); | |
6f94560a | 479 | } while (ret < 0 && errno == EINTR); |
3bd1e081 | 480 | end_nosignal: |
b0b335c8 | 481 | rcu_read_unlock(); |
3bd1e081 MD |
482 | return 0; |
483 | } | |
484 | ||
485 | int lttng_ustconsumer_allocate_channel(struct lttng_consumer_channel *chan) | |
486 | { | |
13161846 | 487 | struct lttng_ust_object_data obj; |
3bd1e081 MD |
488 | |
489 | obj.handle = -1; | |
490 | obj.shm_fd = chan->shm_fd; | |
491 | obj.wait_fd = chan->wait_fd; | |
492 | obj.memory_map_size = chan->mmap_len; | |
493 | chan->handle = ustctl_map_channel(&obj); | |
494 | if (!chan->handle) { | |
495 | return -ENOMEM; | |
496 | } | |
b5c5fc29 | 497 | chan->wait_fd_is_copy = 1; |
2c1dd183 | 498 | chan->shm_fd = -1; |
b5c5fc29 | 499 | |
3bd1e081 MD |
500 | return 0; |
501 | } | |
502 | ||
d056b477 MD |
503 | void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream *stream) |
504 | { | |
505 | ustctl_flush_buffer(stream->chan->handle, stream->buf, 0); | |
effcf122 | 506 | stream->hangup_flush_done = 1; |
d056b477 MD |
507 | } |
508 | ||
3bd1e081 MD |
509 | void lttng_ustconsumer_del_channel(struct lttng_consumer_channel *chan) |
510 | { | |
511 | ustctl_unmap_channel(chan->handle); | |
512 | } | |
513 | ||
514 | int lttng_ustconsumer_allocate_stream(struct lttng_consumer_stream *stream) | |
515 | { | |
13161846 | 516 | struct lttng_ust_object_data obj; |
3bd1e081 MD |
517 | int ret; |
518 | ||
519 | obj.handle = -1; | |
520 | obj.shm_fd = stream->shm_fd; | |
521 | obj.wait_fd = stream->wait_fd; | |
522 | obj.memory_map_size = stream->mmap_len; | |
523 | ret = ustctl_add_stream(stream->chan->handle, &obj); | |
524 | if (ret) | |
525 | return ret; | |
526 | stream->buf = ustctl_open_stream_read(stream->chan->handle, stream->cpu); | |
527 | if (!stream->buf) | |
528 | return -EBUSY; | |
2c1dd183 MD |
529 | /* ustctl_open_stream_read has closed the shm fd. */ |
530 | stream->wait_fd_is_copy = 1; | |
531 | stream->shm_fd = -1; | |
532 | ||
3bd1e081 MD |
533 | stream->mmap_base = ustctl_get_mmap_base(stream->chan->handle, stream->buf); |
534 | if (!stream->mmap_base) { | |
535 | return -EINVAL; | |
536 | } | |
ee77a7b0 | 537 | |
3bd1e081 MD |
538 | return 0; |
539 | } | |
540 | ||
541 | void lttng_ustconsumer_del_stream(struct lttng_consumer_stream *stream) | |
542 | { | |
543 | ustctl_close_stream_read(stream->chan->handle, stream->buf); | |
544 | } | |
d41f73b7 MD |
545 | |
546 | ||
547 | int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream *stream, | |
548 | struct lttng_consumer_local_data *ctx) | |
549 | { | |
550 | unsigned long len; | |
551 | int err; | |
552 | long ret = 0; | |
553 | struct lttng_ust_shm_handle *handle; | |
554 | struct lttng_ust_lib_ring_buffer *buf; | |
555 | char dummy; | |
556 | ssize_t readlen; | |
557 | ||
558 | DBG("In read_subbuffer (wait_fd: %d, stream key: %d)", | |
559 | stream->wait_fd, stream->key); | |
560 | ||
561 | /* We can consume the 1 byte written into the wait_fd by UST */ | |
effcf122 MD |
562 | if (!stream->hangup_flush_done) { |
563 | do { | |
564 | readlen = read(stream->wait_fd, &dummy, 1); | |
87dc6a9c | 565 | } while (readlen == -1 && errno == EINTR); |
effcf122 MD |
566 | if (readlen == -1) { |
567 | ret = readlen; | |
568 | goto end; | |
569 | } | |
d41f73b7 MD |
570 | } |
571 | ||
572 | buf = stream->buf; | |
573 | handle = stream->chan->handle; | |
574 | /* Get the next subbuffer */ | |
575 | err = ustctl_get_next_subbuf(handle, buf); | |
576 | if (err != 0) { | |
effcf122 | 577 | ret = -ret; /* ustctl_get_next_subbuf returns negative, caller expect positive. */ |
d41f73b7 MD |
578 | /* |
579 | * This is a debug message even for single-threaded consumer, | |
580 | * because poll() have more relaxed criterions than get subbuf, | |
581 | * so get_subbuf may fail for short race windows where poll() | |
582 | * would issue wakeups. | |
583 | */ | |
584 | DBG("Reserving sub buffer failed (everything is normal, " | |
585 | "it is due to concurrency)"); | |
586 | goto end; | |
587 | } | |
588 | assert(stream->output == LTTNG_EVENT_MMAP); | |
589 | /* read the used subbuffer size */ | |
590 | err = ustctl_get_padded_subbuf_size(handle, buf, &len); | |
effcf122 | 591 | assert(err == 0); |
d41f73b7 MD |
592 | /* write the subbuffer to the tracefile */ |
593 | ret = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, len); | |
47e81c02 | 594 | if (ret != len) { |
d41f73b7 MD |
595 | /* |
596 | * display the error but continue processing to try | |
597 | * to release the subbuffer | |
598 | */ | |
599 | ERR("Error writing to tracefile"); | |
600 | } | |
601 | err = ustctl_put_next_subbuf(handle, buf); | |
effcf122 | 602 | assert(err == 0); |
d41f73b7 MD |
603 | end: |
604 | return ret; | |
605 | } | |
606 | ||
607 | int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream *stream) | |
608 | { | |
609 | int ret; | |
610 | ||
611 | /* Opening the tracefile in write mode */ | |
00e2e675 | 612 | if (stream->path_name != NULL && stream->net_seq_idx == -1) { |
e11d277b | 613 | ret = run_as_open(stream->path_name, |
60b6c79c MD |
614 | O_WRONLY|O_CREAT|O_TRUNC, |
615 | S_IRWXU|S_IRWXG|S_IRWXO, | |
616 | stream->uid, stream->gid); | |
d41f73b7 MD |
617 | if (ret < 0) { |
618 | ERR("Opening %s", stream->path_name); | |
4c462e79 | 619 | PERROR("open"); |
d41f73b7 MD |
620 | goto error; |
621 | } | |
622 | stream->out_fd = ret; | |
623 | } | |
624 | ||
625 | /* we return 0 to let the library handle the FD internally */ | |
626 | return 0; | |
627 | ||
628 | error: | |
629 | return ret; | |
630 | } |