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> | |
f02e1e8a | 21 | #include <lttng/ust-ctl.h> |
3bd1e081 MD |
22 | #include <poll.h> |
23 | #include <pthread.h> | |
24 | #include <stdlib.h> | |
25 | #include <string.h> | |
26 | #include <sys/mman.h> | |
27 | #include <sys/socket.h> | |
dbb5dfe6 | 28 | #include <sys/stat.h> |
3bd1e081 | 29 | #include <sys/types.h> |
77c7c900 | 30 | #include <inttypes.h> |
3bd1e081 | 31 | #include <unistd.h> |
0857097f | 32 | |
990570ed | 33 | #include <common/common.h> |
10a8a223 | 34 | #include <common/sessiond-comm/sessiond-comm.h> |
00e2e675 | 35 | #include <common/relayd/relayd.h> |
dbb5dfe6 | 36 | #include <common/compat/fcntl.h> |
10a8a223 DG |
37 | |
38 | #include "ust-consumer.h" | |
3bd1e081 MD |
39 | |
40 | extern struct lttng_consumer_global_data consumer_data; | |
41 | extern int consumer_poll_timeout; | |
42 | extern volatile int consumer_quit; | |
43 | ||
44 | /* | |
f02e1e8a DG |
45 | * Wrapper over the mmap() read offset from ust-ctl library. Since this can be |
46 | * compiled out, we isolate it in this library. | |
3bd1e081 | 47 | */ |
f02e1e8a DG |
48 | int lttng_ustctl_get_mmap_read_offset(struct lttng_ust_shm_handle *handle, |
49 | struct lttng_ust_lib_ring_buffer *buf, unsigned long *off) | |
3bd1e081 | 50 | { |
f02e1e8a DG |
51 | return ustctl_get_mmap_read_offset(handle, buf, off); |
52 | }; | |
3bd1e081 MD |
53 | |
54 | /* | |
55 | * Take a snapshot for a specific fd | |
56 | * | |
57 | * Returns 0 on success, < 0 on error | |
58 | */ | |
59 | int lttng_ustconsumer_take_snapshot(struct lttng_consumer_local_data *ctx, | |
60 | struct lttng_consumer_stream *stream) | |
61 | { | |
62 | int ret = 0; | |
63 | ||
64 | ret = ustctl_snapshot(stream->chan->handle, stream->buf); | |
65 | if (ret != 0) { | |
87dc6a9c | 66 | errno = -ret; |
4c462e79 | 67 | PERROR("Getting sub-buffer snapshot."); |
3bd1e081 MD |
68 | } |
69 | ||
70 | return ret; | |
71 | } | |
72 | ||
73 | /* | |
74 | * Get the produced position | |
75 | * | |
76 | * Returns 0 on success, < 0 on error | |
77 | */ | |
78 | int lttng_ustconsumer_get_produced_snapshot( | |
79 | struct lttng_consumer_local_data *ctx, | |
80 | struct lttng_consumer_stream *stream, | |
81 | unsigned long *pos) | |
82 | { | |
83 | int ret; | |
84 | ||
85 | ret = ustctl_snapshot_get_produced(stream->chan->handle, | |
86 | stream->buf, pos); | |
87 | if (ret != 0) { | |
87dc6a9c | 88 | errno = -ret; |
3be74084 | 89 | PERROR("ustctl_snapshot_get_produced"); |
3bd1e081 MD |
90 | } |
91 | ||
92 | return ret; | |
93 | } | |
94 | ||
4cbc1a04 DG |
95 | /* |
96 | * Receive command from session daemon and process it. | |
97 | * | |
98 | * Return 1 on success else a negative value or 0. | |
99 | */ | |
3bd1e081 MD |
100 | int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data *ctx, |
101 | int sock, struct pollfd *consumer_sockpoll) | |
102 | { | |
103 | ssize_t ret; | |
f50f23d9 | 104 | enum lttng_error_code ret_code = LTTNG_OK; |
3bd1e081 MD |
105 | struct lttcomm_consumer_msg msg; |
106 | ||
107 | ret = lttcomm_recv_unix_sock(sock, &msg, sizeof(msg)); | |
108 | if (ret != sizeof(msg)) { | |
173af62f DG |
109 | DBG("Consumer received unexpected message size %zd (expects %zu)", |
110 | ret, sizeof(msg)); | |
f73fabfd | 111 | lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_ERROR_RECV_FD); |
3be74084 DG |
112 | /* |
113 | * The ret value might 0 meaning an orderly shutdown but this is ok | |
114 | * since the caller handles this. | |
115 | */ | |
3bd1e081 MD |
116 | return ret; |
117 | } | |
118 | if (msg.cmd_type == LTTNG_CONSUMER_STOP) { | |
f50f23d9 DG |
119 | /* |
120 | * Notify the session daemon that the command is completed. | |
121 | * | |
122 | * On transport layer error, the function call will print an error | |
123 | * message so handling the returned code is a bit useless since we | |
124 | * return an error code anyway. | |
125 | */ | |
126 | (void) consumer_send_status_msg(sock, ret_code); | |
3bd1e081 MD |
127 | return -ENOENT; |
128 | } | |
129 | ||
3f8e211f | 130 | /* relayd needs RCU read-side lock */ |
b0b335c8 MD |
131 | rcu_read_lock(); |
132 | ||
3bd1e081 | 133 | switch (msg.cmd_type) { |
00e2e675 DG |
134 | case LTTNG_CONSUMER_ADD_RELAYD_SOCKET: |
135 | { | |
f50f23d9 | 136 | /* Session daemon status message are handled in the following call. */ |
7735ef9e DG |
137 | ret = consumer_add_relayd_socket(msg.u.relayd_sock.net_index, |
138 | msg.u.relayd_sock.type, ctx, sock, consumer_sockpoll, | |
46e6455f | 139 | &msg.u.relayd_sock.sock, msg.u.relayd_sock.session_id); |
00e2e675 DG |
140 | goto end_nosignal; |
141 | } | |
3bd1e081 MD |
142 | case LTTNG_CONSUMER_ADD_CHANNEL: |
143 | { | |
144 | struct lttng_consumer_channel *new_channel; | |
145 | int fds[1]; | |
146 | size_t nb_fd = 1; | |
147 | ||
173af62f DG |
148 | DBG("UST Consumer adding channel"); |
149 | ||
f50f23d9 DG |
150 | /* First send a status message before receiving the fds. */ |
151 | ret = consumer_send_status_msg(sock, ret_code); | |
152 | if (ret < 0) { | |
153 | /* Somehow, the session daemon is not responding anymore. */ | |
154 | goto end_nosignal; | |
155 | } | |
156 | ||
3bd1e081 MD |
157 | /* block */ |
158 | if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) { | |
3f8e211f | 159 | rcu_read_unlock(); |
3bd1e081 MD |
160 | return -EINTR; |
161 | } | |
162 | ret = lttcomm_recv_fds_unix_sock(sock, fds, nb_fd); | |
163 | if (ret != sizeof(fds)) { | |
f73fabfd | 164 | lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_ERROR_RECV_FD); |
3f8e211f | 165 | rcu_read_unlock(); |
3be74084 DG |
166 | /* |
167 | * The ret value might 0 meaning an orderly shutdown but this is ok | |
168 | * since the caller handles this. | |
169 | */ | |
3bd1e081 MD |
170 | return ret; |
171 | } | |
172 | ||
f50f23d9 DG |
173 | /* |
174 | * Send status code to session daemon only if the recv works. If the | |
175 | * above recv() failed, the session daemon is notified through the | |
176 | * error socket and the teardown is eventually done. | |
177 | */ | |
178 | ret = consumer_send_status_msg(sock, ret_code); | |
179 | if (ret < 0) { | |
180 | /* Somehow, the session daemon is not responding anymore. */ | |
181 | goto end_nosignal; | |
182 | } | |
183 | ||
3bd1e081 MD |
184 | DBG("consumer_add_channel %d", msg.u.channel.channel_key); |
185 | ||
186 | new_channel = consumer_allocate_channel(msg.u.channel.channel_key, | |
187 | fds[0], -1, | |
188 | msg.u.channel.mmap_len, | |
c30aaa51 MD |
189 | msg.u.channel.max_sb_size, |
190 | msg.u.channel.nb_init_streams); | |
3bd1e081 | 191 | if (new_channel == NULL) { |
f73fabfd | 192 | lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_OUTFD_ERROR); |
3bd1e081 MD |
193 | goto end_nosignal; |
194 | } | |
195 | if (ctx->on_recv_channel != NULL) { | |
196 | ret = ctx->on_recv_channel(new_channel); | |
197 | if (ret == 0) { | |
198 | consumer_add_channel(new_channel); | |
199 | } else if (ret < 0) { | |
200 | goto end_nosignal; | |
201 | } | |
202 | } else { | |
203 | consumer_add_channel(new_channel); | |
204 | } | |
205 | goto end_nosignal; | |
206 | } | |
207 | case LTTNG_CONSUMER_ADD_STREAM: | |
208 | { | |
209 | struct lttng_consumer_stream *new_stream; | |
50f8ae69 | 210 | int fds[2], stream_pipe; |
3bd1e081 | 211 | size_t nb_fd = 2; |
00e2e675 | 212 | struct consumer_relayd_sock_pair *relayd = NULL; |
c80048c6 | 213 | int alloc_ret = 0; |
3bd1e081 | 214 | |
173af62f DG |
215 | DBG("UST Consumer adding stream"); |
216 | ||
f50f23d9 DG |
217 | /* First send a status message before receiving the fds. */ |
218 | ret = consumer_send_status_msg(sock, ret_code); | |
219 | if (ret < 0) { | |
220 | /* Somehow, the session daemon is not responding anymore. */ | |
221 | goto end_nosignal; | |
222 | } | |
223 | ||
3bd1e081 MD |
224 | /* block */ |
225 | if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) { | |
3f8e211f | 226 | rcu_read_unlock(); |
3bd1e081 MD |
227 | return -EINTR; |
228 | } | |
229 | ret = lttcomm_recv_fds_unix_sock(sock, fds, nb_fd); | |
230 | if (ret != sizeof(fds)) { | |
f73fabfd | 231 | lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_ERROR_RECV_FD); |
3f8e211f | 232 | rcu_read_unlock(); |
3be74084 DG |
233 | /* |
234 | * The ret value might 0 meaning an orderly shutdown but this is ok | |
235 | * since the caller handles this. | |
236 | */ | |
3bd1e081 MD |
237 | return ret; |
238 | } | |
239 | ||
f50f23d9 DG |
240 | /* |
241 | * Send status code to session daemon only if the recv works. If the | |
242 | * above recv() failed, the session daemon is notified through the | |
243 | * error socket and the teardown is eventually done. | |
244 | */ | |
245 | ret = consumer_send_status_msg(sock, ret_code); | |
246 | if (ret < 0) { | |
247 | /* Somehow, the session daemon is not responding anymore. */ | |
248 | goto end_nosignal; | |
249 | } | |
250 | ||
7a57cf92 DG |
251 | DBG("Consumer command ADD_STREAM chan %d stream %d", |
252 | msg.u.stream.channel_key, msg.u.stream.stream_key); | |
173af62f | 253 | |
d41f73b7 | 254 | assert(msg.u.stream.output == LTTNG_EVENT_MMAP); |
173af62f | 255 | new_stream = consumer_allocate_stream(msg.u.stream.channel_key, |
3bd1e081 MD |
256 | msg.u.stream.stream_key, |
257 | fds[0], fds[1], | |
258 | msg.u.stream.state, | |
259 | msg.u.stream.mmap_len, | |
260 | msg.u.stream.output, | |
6df2e2c9 MD |
261 | msg.u.stream.path_name, |
262 | msg.u.stream.uid, | |
00e2e675 DG |
263 | msg.u.stream.gid, |
264 | msg.u.stream.net_index, | |
c80048c6 | 265 | msg.u.stream.metadata_flag, |
53632229 | 266 | msg.u.stream.session_id, |
c80048c6 | 267 | &alloc_ret); |
3bd1e081 | 268 | if (new_stream == NULL) { |
c80048c6 MD |
269 | switch (alloc_ret) { |
270 | case -ENOMEM: | |
271 | case -EINVAL: | |
272 | default: | |
273 | lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_OUTFD_ERROR); | |
274 | break; | |
275 | case -ENOENT: | |
276 | /* | |
277 | * We could not find the channel. Can happen if cpu hotplug | |
278 | * happens while tearing down. | |
279 | */ | |
280 | DBG3("Could not find channel"); | |
281 | break; | |
282 | } | |
3f8e211f | 283 | goto end_nosignal; |
3bd1e081 | 284 | } |
00e2e675 DG |
285 | |
286 | /* The stream is not metadata. Get relayd reference if exists. */ | |
287 | relayd = consumer_find_relayd(msg.u.stream.net_index); | |
288 | if (relayd != NULL) { | |
289 | pthread_mutex_lock(&relayd->ctrl_sock_mutex); | |
290 | /* Add stream on the relayd */ | |
291 | ret = relayd_add_stream(&relayd->control_sock, | |
292 | msg.u.stream.name, msg.u.stream.path_name, | |
293 | &new_stream->relayd_stream_id); | |
294 | pthread_mutex_unlock(&relayd->ctrl_sock_mutex); | |
295 | if (ret < 0) { | |
e316aad5 | 296 | consumer_del_stream(new_stream, NULL); |
3f8e211f | 297 | goto end_nosignal; |
00e2e675 DG |
298 | } |
299 | } else if (msg.u.stream.net_index != -1) { | |
300 | ERR("Network sequence index %d unknown. Not adding stream.", | |
301 | msg.u.stream.net_index); | |
e316aad5 | 302 | consumer_del_stream(new_stream, NULL); |
3f8e211f | 303 | goto end_nosignal; |
00e2e675 DG |
304 | } |
305 | ||
633d0084 DG |
306 | /* Do actions once stream has been received. */ |
307 | if (ctx->on_recv_stream) { | |
308 | ret = ctx->on_recv_stream(new_stream); | |
309 | if (ret < 0) { | |
e316aad5 | 310 | consumer_del_stream(new_stream, NULL); |
633d0084 | 311 | goto end_nosignal; |
fb3a43a9 | 312 | } |
633d0084 | 313 | } |
fb3a43a9 | 314 | |
50f8ae69 | 315 | /* Get the right pipe where the stream will be sent. */ |
633d0084 | 316 | if (new_stream->metadata_flag) { |
50f8ae69 | 317 | stream_pipe = ctx->consumer_metadata_pipe[1]; |
3bd1e081 | 318 | } else { |
50f8ae69 DG |
319 | stream_pipe = ctx->consumer_data_pipe[1]; |
320 | } | |
321 | ||
322 | do { | |
323 | ret = write(stream_pipe, &new_stream, sizeof(new_stream)); | |
324 | } while (ret < 0 && errno == EINTR); | |
325 | if (ret < 0) { | |
326 | PERROR("Consumer write %s stream to pipe %d", | |
327 | new_stream->metadata_flag ? "metadata" : "data", | |
328 | stream_pipe); | |
329 | consumer_del_stream(new_stream, NULL); | |
330 | goto end_nosignal; | |
3bd1e081 | 331 | } |
00e2e675 | 332 | |
50f8ae69 | 333 | DBG("UST consumer ADD_STREAM %s (%d,%d) with relayd id %" PRIu64, |
00e2e675 DG |
334 | msg.u.stream.path_name, fds[0], fds[1], |
335 | new_stream->relayd_stream_id); | |
3bd1e081 MD |
336 | break; |
337 | } | |
173af62f DG |
338 | case LTTNG_CONSUMER_DESTROY_RELAYD: |
339 | { | |
a6ba4fe1 | 340 | uint64_t index = msg.u.destroy_relayd.net_seq_idx; |
173af62f DG |
341 | struct consumer_relayd_sock_pair *relayd; |
342 | ||
a6ba4fe1 | 343 | DBG("UST consumer destroying relayd %" PRIu64, index); |
173af62f DG |
344 | |
345 | /* Get relayd reference if exists. */ | |
a6ba4fe1 | 346 | relayd = consumer_find_relayd(index); |
173af62f | 347 | if (relayd == NULL) { |
3448e266 | 348 | DBG("Unable to find relayd %" PRIu64, index); |
f50f23d9 | 349 | ret_code = LTTNG_ERR_NO_CONSUMER; |
173af62f DG |
350 | } |
351 | ||
a6ba4fe1 DG |
352 | /* |
353 | * Each relayd socket pair has a refcount of stream attached to it | |
354 | * which tells if the relayd is still active or not depending on the | |
355 | * refcount value. | |
356 | * | |
357 | * This will set the destroy flag of the relayd object and destroy it | |
358 | * if the refcount reaches zero when called. | |
359 | * | |
360 | * The destroy can happen either here or when a stream fd hangs up. | |
361 | */ | |
f50f23d9 DG |
362 | if (relayd) { |
363 | consumer_flag_relayd_for_destroy(relayd); | |
364 | } | |
365 | ||
366 | ret = consumer_send_status_msg(sock, ret_code); | |
367 | if (ret < 0) { | |
368 | /* Somehow, the session daemon is not responding anymore. */ | |
369 | goto end_nosignal; | |
370 | } | |
173af62f | 371 | |
3f8e211f | 372 | goto end_nosignal; |
173af62f | 373 | } |
3bd1e081 MD |
374 | case LTTNG_CONSUMER_UPDATE_STREAM: |
375 | { | |
3f8e211f | 376 | rcu_read_unlock(); |
7ad0a0cb | 377 | return -ENOSYS; |
3bd1e081 | 378 | } |
6d805429 | 379 | case LTTNG_CONSUMER_DATA_PENDING: |
53632229 | 380 | { |
3be74084 | 381 | int ret, is_data_pending; |
6d805429 | 382 | uint64_t id = msg.u.data_pending.session_id; |
ca22feea | 383 | |
6d805429 | 384 | DBG("UST consumer data pending command for id %" PRIu64, id); |
ca22feea | 385 | |
3be74084 | 386 | is_data_pending = consumer_data_pending(id); |
ca22feea DG |
387 | |
388 | /* Send back returned value to session daemon */ | |
3be74084 DG |
389 | ret = lttcomm_send_unix_sock(sock, &is_data_pending, |
390 | sizeof(is_data_pending)); | |
ca22feea | 391 | if (ret < 0) { |
3be74084 | 392 | DBG("Error when sending the data pending ret code: %d", ret); |
ca22feea | 393 | } |
f50f23d9 DG |
394 | |
395 | /* | |
396 | * No need to send back a status message since the data pending | |
397 | * returned value is the response. | |
398 | */ | |
ca22feea | 399 | break; |
53632229 | 400 | } |
3bd1e081 MD |
401 | default: |
402 | break; | |
403 | } | |
3f8e211f | 404 | |
3bd1e081 | 405 | end_nosignal: |
b0b335c8 | 406 | rcu_read_unlock(); |
4cbc1a04 DG |
407 | |
408 | /* | |
409 | * Return 1 to indicate success since the 0 value can be a socket | |
410 | * shutdown during the recv() or send() call. | |
411 | */ | |
412 | return 1; | |
3bd1e081 MD |
413 | } |
414 | ||
415 | int lttng_ustconsumer_allocate_channel(struct lttng_consumer_channel *chan) | |
416 | { | |
13161846 | 417 | struct lttng_ust_object_data obj; |
3bd1e081 MD |
418 | |
419 | obj.handle = -1; | |
420 | obj.shm_fd = chan->shm_fd; | |
421 | obj.wait_fd = chan->wait_fd; | |
422 | obj.memory_map_size = chan->mmap_len; | |
423 | chan->handle = ustctl_map_channel(&obj); | |
424 | if (!chan->handle) { | |
425 | return -ENOMEM; | |
426 | } | |
b5c5fc29 | 427 | chan->wait_fd_is_copy = 1; |
2c1dd183 | 428 | chan->shm_fd = -1; |
b5c5fc29 | 429 | |
3bd1e081 MD |
430 | return 0; |
431 | } | |
432 | ||
d056b477 MD |
433 | void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream *stream) |
434 | { | |
435 | ustctl_flush_buffer(stream->chan->handle, stream->buf, 0); | |
effcf122 | 436 | stream->hangup_flush_done = 1; |
d056b477 MD |
437 | } |
438 | ||
3bd1e081 MD |
439 | void lttng_ustconsumer_del_channel(struct lttng_consumer_channel *chan) |
440 | { | |
441 | ustctl_unmap_channel(chan->handle); | |
442 | } | |
443 | ||
e316aad5 | 444 | int lttng_ustconsumer_add_stream(struct lttng_consumer_stream *stream) |
3bd1e081 | 445 | { |
13161846 | 446 | struct lttng_ust_object_data obj; |
3bd1e081 MD |
447 | int ret; |
448 | ||
449 | obj.handle = -1; | |
450 | obj.shm_fd = stream->shm_fd; | |
451 | obj.wait_fd = stream->wait_fd; | |
452 | obj.memory_map_size = stream->mmap_len; | |
453 | ret = ustctl_add_stream(stream->chan->handle, &obj); | |
7a57cf92 DG |
454 | if (ret) { |
455 | ERR("UST ctl add_stream failed with ret %d", ret); | |
e316aad5 | 456 | goto error; |
7a57cf92 DG |
457 | } |
458 | ||
3bd1e081 | 459 | stream->buf = ustctl_open_stream_read(stream->chan->handle, stream->cpu); |
7a57cf92 DG |
460 | if (!stream->buf) { |
461 | ERR("UST ctl open_stream_read failed"); | |
e316aad5 DG |
462 | ret = -EBUSY; |
463 | goto error; | |
7a57cf92 DG |
464 | } |
465 | ||
2c1dd183 MD |
466 | /* ustctl_open_stream_read has closed the shm fd. */ |
467 | stream->wait_fd_is_copy = 1; | |
468 | stream->shm_fd = -1; | |
469 | ||
3bd1e081 MD |
470 | stream->mmap_base = ustctl_get_mmap_base(stream->chan->handle, stream->buf); |
471 | if (!stream->mmap_base) { | |
7a57cf92 | 472 | ERR("UST ctl get_mmap_base failed"); |
e316aad5 DG |
473 | ret = -EINVAL; |
474 | goto mmap_error; | |
3bd1e081 | 475 | } |
ee77a7b0 | 476 | |
3bd1e081 | 477 | return 0; |
e316aad5 DG |
478 | |
479 | mmap_error: | |
480 | ustctl_close_stream_read(stream->chan->handle, stream->buf); | |
481 | error: | |
482 | return ret; | |
3bd1e081 MD |
483 | } |
484 | ||
485 | void lttng_ustconsumer_del_stream(struct lttng_consumer_stream *stream) | |
486 | { | |
487 | ustctl_close_stream_read(stream->chan->handle, stream->buf); | |
488 | } | |
d41f73b7 MD |
489 | |
490 | ||
491 | int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream *stream, | |
492 | struct lttng_consumer_local_data *ctx) | |
493 | { | |
1d4dfdef | 494 | unsigned long len, subbuf_size, padding; |
d41f73b7 MD |
495 | int err; |
496 | long ret = 0; | |
497 | struct lttng_ust_shm_handle *handle; | |
498 | struct lttng_ust_lib_ring_buffer *buf; | |
499 | char dummy; | |
d41f73b7 MD |
500 | |
501 | DBG("In read_subbuffer (wait_fd: %d, stream key: %d)", | |
502 | stream->wait_fd, stream->key); | |
503 | ||
504 | /* We can consume the 1 byte written into the wait_fd by UST */ | |
effcf122 | 505 | if (!stream->hangup_flush_done) { |
c617c0c6 MD |
506 | ssize_t readlen; |
507 | ||
effcf122 MD |
508 | do { |
509 | readlen = read(stream->wait_fd, &dummy, 1); | |
87dc6a9c | 510 | } while (readlen == -1 && errno == EINTR); |
effcf122 MD |
511 | if (readlen == -1) { |
512 | ret = readlen; | |
513 | goto end; | |
514 | } | |
d41f73b7 MD |
515 | } |
516 | ||
517 | buf = stream->buf; | |
518 | handle = stream->chan->handle; | |
519 | /* Get the next subbuffer */ | |
520 | err = ustctl_get_next_subbuf(handle, buf); | |
521 | if (err != 0) { | |
1d4dfdef | 522 | ret = err; /* ustctl_get_next_subbuf returns negative, caller expect positive. */ |
d41f73b7 MD |
523 | /* |
524 | * This is a debug message even for single-threaded consumer, | |
525 | * because poll() have more relaxed criterions than get subbuf, | |
526 | * so get_subbuf may fail for short race windows where poll() | |
527 | * would issue wakeups. | |
528 | */ | |
529 | DBG("Reserving sub buffer failed (everything is normal, " | |
530 | "it is due to concurrency)"); | |
531 | goto end; | |
532 | } | |
533 | assert(stream->output == LTTNG_EVENT_MMAP); | |
1d4dfdef | 534 | /* Get the full padded subbuffer size */ |
d41f73b7 | 535 | err = ustctl_get_padded_subbuf_size(handle, buf, &len); |
effcf122 | 536 | assert(err == 0); |
1d4dfdef DG |
537 | |
538 | /* Get subbuffer data size (without padding) */ | |
539 | err = ustctl_get_subbuf_size(handle, buf, &subbuf_size); | |
540 | assert(err == 0); | |
541 | ||
542 | /* Make sure we don't get a subbuffer size bigger than the padded */ | |
543 | assert(len >= subbuf_size); | |
544 | ||
545 | padding = len - subbuf_size; | |
d41f73b7 | 546 | /* write the subbuffer to the tracefile */ |
1d4dfdef | 547 | ret = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, subbuf_size, padding); |
91dfef6e DG |
548 | /* |
549 | * The mmap operation should write subbuf_size amount of data when network | |
550 | * streaming or the full padding (len) size when we are _not_ streaming. | |
551 | */ | |
552 | if ((ret != subbuf_size && stream->net_seq_idx != -1) || | |
553 | (ret != len && stream->net_seq_idx == -1)) { | |
d41f73b7 | 554 | /* |
91dfef6e | 555 | * Display the error but continue processing to try to release the |
c5c45efa DG |
556 | * subbuffer. This is a DBG statement since any unexpected kill or |
557 | * signal, the application gets unregistered, relayd gets closed or | |
558 | * anything that affects the buffer lifetime will trigger this error. | |
559 | * So, for the sake of the user, don't print this error since it can | |
560 | * happen and it is OK with the code flow. | |
d41f73b7 | 561 | */ |
c5c45efa | 562 | DBG("Error writing to tracefile " |
91dfef6e DG |
563 | "(ret: %zd != len: %lu != subbuf_size: %lu)", |
564 | ret, len, subbuf_size); | |
d41f73b7 MD |
565 | } |
566 | err = ustctl_put_next_subbuf(handle, buf); | |
effcf122 | 567 | assert(err == 0); |
d41f73b7 MD |
568 | end: |
569 | return ret; | |
570 | } | |
571 | ||
572 | int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream *stream) | |
573 | { | |
574 | int ret; | |
575 | ||
576 | /* Opening the tracefile in write mode */ | |
00e2e675 | 577 | if (stream->path_name != NULL && stream->net_seq_idx == -1) { |
e11d277b | 578 | ret = run_as_open(stream->path_name, |
60b6c79c MD |
579 | O_WRONLY|O_CREAT|O_TRUNC, |
580 | S_IRWXU|S_IRWXG|S_IRWXO, | |
581 | stream->uid, stream->gid); | |
d41f73b7 MD |
582 | if (ret < 0) { |
583 | ERR("Opening %s", stream->path_name); | |
4c462e79 | 584 | PERROR("open"); |
d41f73b7 MD |
585 | goto error; |
586 | } | |
587 | stream->out_fd = ret; | |
588 | } | |
589 | ||
c869f647 DG |
590 | ret = lttng_ustconsumer_add_stream(stream); |
591 | if (ret) { | |
592 | consumer_del_stream(stream, NULL); | |
593 | ret = -1; | |
594 | goto error; | |
595 | } | |
596 | ||
d41f73b7 MD |
597 | /* we return 0 to let the library handle the FD internally */ |
598 | return 0; | |
599 | ||
600 | error: | |
601 | return ret; | |
602 | } | |
ca22feea DG |
603 | |
604 | /* | |
605 | * Check if data is still being extracted from the buffers for a specific | |
4e9a4686 DG |
606 | * stream. Consumer data lock MUST be acquired before calling this function |
607 | * and the stream lock. | |
ca22feea | 608 | * |
6d805429 | 609 | * Return 1 if the traced data are still getting read else 0 meaning that the |
ca22feea DG |
610 | * data is available for trace viewer reading. |
611 | */ | |
6d805429 | 612 | int lttng_ustconsumer_data_pending(struct lttng_consumer_stream *stream) |
ca22feea DG |
613 | { |
614 | int ret; | |
615 | ||
616 | assert(stream); | |
617 | ||
6d805429 | 618 | DBG("UST consumer checking data pending"); |
c8f59ee5 | 619 | |
ca22feea DG |
620 | ret = ustctl_get_next_subbuf(stream->chan->handle, stream->buf); |
621 | if (ret == 0) { | |
622 | /* There is still data so let's put back this subbuffer. */ | |
623 | ret = ustctl_put_subbuf(stream->chan->handle, stream->buf); | |
624 | assert(ret == 0); | |
6d805429 | 625 | ret = 1; /* Data is pending */ |
4e9a4686 | 626 | goto end; |
ca22feea DG |
627 | } |
628 | ||
6d805429 DG |
629 | /* Data is NOT pending so ready to be read. */ |
630 | ret = 0; | |
ca22feea | 631 | |
6efae65e DG |
632 | end: |
633 | return ret; | |
ca22feea | 634 | } |