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> | |
27 | #include <sys/types.h> | |
28 | #include <unistd.h> | |
dbb5dfe6 | 29 | #include <sys/stat.h> |
3bd1e081 | 30 | |
990570ed | 31 | #include <common/common.h> |
10a8a223 | 32 | #include <common/kernel-ctl/kernel-ctl.h> |
10a8a223 | 33 | #include <common/sessiond-comm/sessiond-comm.h> |
00e2e675 | 34 | #include <common/sessiond-comm/relayd.h> |
dbb5dfe6 | 35 | #include <common/compat/fcntl.h> |
00e2e675 | 36 | #include <common/relayd/relayd.h> |
0857097f | 37 | |
10a8a223 | 38 | #include "kernel-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 | ||
3bd1e081 MD |
44 | /* |
45 | * Take a snapshot for a specific fd | |
46 | * | |
47 | * Returns 0 on success, < 0 on error | |
48 | */ | |
49 | int lttng_kconsumer_take_snapshot(struct lttng_consumer_local_data *ctx, | |
50 | struct lttng_consumer_stream *stream) | |
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 | */ | |
69 | int lttng_kconsumer_get_produced_snapshot( | |
70 | struct lttng_consumer_local_data *ctx, | |
71 | struct lttng_consumer_stream *stream, | |
72 | unsigned long *pos) | |
73 | { | |
74 | int ret; | |
75 | int infd = stream->wait_fd; | |
76 | ||
77 | ret = kernctl_snapshot_get_produced(infd, pos); | |
78 | if (ret != 0) { | |
87dc6a9c | 79 | errno = -ret; |
3bd1e081 MD |
80 | perror("kernctl_snapshot_get_produced"); |
81 | } | |
82 | ||
83 | return ret; | |
84 | } | |
85 | ||
86 | int lttng_kconsumer_recv_cmd(struct lttng_consumer_local_data *ctx, | |
87 | int sock, struct pollfd *consumer_sockpoll) | |
88 | { | |
89 | ssize_t ret; | |
90 | struct lttcomm_consumer_msg msg; | |
91 | ||
92 | ret = lttcomm_recv_unix_sock(sock, &msg, sizeof(msg)); | |
93 | if (ret != sizeof(msg)) { | |
f2fc6720 | 94 | lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_CMD); |
3bd1e081 MD |
95 | return ret; |
96 | } | |
97 | if (msg.cmd_type == LTTNG_CONSUMER_STOP) { | |
98 | return -ENOENT; | |
99 | } | |
100 | ||
b0b335c8 MD |
101 | /* relayd needs RCU read-side protection */ |
102 | rcu_read_lock(); | |
103 | ||
3bd1e081 | 104 | switch (msg.cmd_type) { |
00e2e675 DG |
105 | case LTTNG_CONSUMER_ADD_RELAYD_SOCKET: |
106 | { | |
107 | int fd; | |
108 | struct consumer_relayd_sock_pair *relayd; | |
109 | ||
110 | DBG("Consumer adding relayd socket"); | |
111 | ||
112 | /* Get relayd reference if exists. */ | |
113 | relayd = consumer_find_relayd(msg.u.relayd_sock.net_index); | |
114 | if (relayd == NULL) { | |
115 | /* Not found. Allocate one. */ | |
116 | relayd = consumer_allocate_relayd_sock_pair( | |
117 | msg.u.relayd_sock.net_index); | |
118 | if (relayd == NULL) { | |
119 | lttng_consumer_send_error(ctx, CONSUMERD_OUTFD_ERROR); | |
120 | goto end_nosignal; | |
121 | } | |
122 | } | |
123 | ||
124 | /* Poll on consumer socket. */ | |
125 | if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) { | |
126 | return -EINTR; | |
127 | } | |
128 | ||
129 | /* Get relayd socket from session daemon */ | |
130 | ret = lttcomm_recv_fds_unix_sock(sock, &fd, 1); | |
131 | if (ret != sizeof(fd)) { | |
132 | lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD); | |
133 | goto end_nosignal; | |
134 | } | |
135 | ||
136 | /* Copy socket information and received FD */ | |
137 | switch (msg.u.relayd_sock.type) { | |
138 | case LTTNG_STREAM_CONTROL: | |
139 | /* Copy received lttcomm socket */ | |
140 | lttcomm_copy_sock(&relayd->control_sock, &msg.u.relayd_sock.sock); | |
141 | ||
142 | ret = lttcomm_create_sock(&relayd->control_sock); | |
143 | if (ret < 0) { | |
144 | goto end_nosignal; | |
145 | } | |
146 | ||
147 | /* Close the created socket fd which is useless */ | |
148 | close(relayd->control_sock.fd); | |
149 | ||
150 | /* Assign new file descriptor */ | |
151 | relayd->control_sock.fd = fd; | |
152 | break; | |
153 | case LTTNG_STREAM_DATA: | |
154 | /* Copy received lttcomm socket */ | |
155 | lttcomm_copy_sock(&relayd->data_sock, &msg.u.relayd_sock.sock); | |
156 | ret = lttcomm_create_sock(&relayd->data_sock); | |
157 | if (ret < 0) { | |
158 | goto end_nosignal; | |
159 | } | |
160 | ||
161 | /* Close the created socket fd which is useless */ | |
162 | close(relayd->data_sock.fd); | |
163 | ||
164 | /* Assign new file descriptor */ | |
165 | relayd->data_sock.fd = fd; | |
166 | break; | |
167 | default: | |
168 | ERR("Unknown relayd socket type"); | |
169 | goto end_nosignal; | |
170 | } | |
171 | ||
172 | DBG("Consumer %s socket created successfully with net idx %d (fd: %d)", | |
173 | msg.u.relayd_sock.type == LTTNG_STREAM_CONTROL ? "control" : "data", | |
174 | relayd->net_seq_idx, fd); | |
175 | ||
176 | /* | |
177 | * Add relayd socket pair to consumer data hashtable. If object already | |
178 | * exists or on error, the function gracefully returns. | |
179 | */ | |
180 | consumer_add_relayd(relayd); | |
181 | ||
182 | goto end_nosignal; | |
183 | } | |
3bd1e081 MD |
184 | case LTTNG_CONSUMER_ADD_CHANNEL: |
185 | { | |
186 | struct lttng_consumer_channel *new_channel; | |
187 | ||
188 | DBG("consumer_add_channel %d", msg.u.channel.channel_key); | |
189 | new_channel = consumer_allocate_channel(msg.u.channel.channel_key, | |
190 | -1, -1, | |
191 | msg.u.channel.mmap_len, | |
192 | msg.u.channel.max_sb_size); | |
193 | if (new_channel == NULL) { | |
194 | lttng_consumer_send_error(ctx, CONSUMERD_OUTFD_ERROR); | |
195 | goto end_nosignal; | |
196 | } | |
197 | if (ctx->on_recv_channel != NULL) { | |
198 | ret = ctx->on_recv_channel(new_channel); | |
199 | if (ret == 0) { | |
200 | consumer_add_channel(new_channel); | |
201 | } else if (ret < 0) { | |
202 | goto end_nosignal; | |
203 | } | |
204 | } else { | |
205 | consumer_add_channel(new_channel); | |
206 | } | |
207 | goto end_nosignal; | |
208 | } | |
209 | case LTTNG_CONSUMER_ADD_STREAM: | |
210 | { | |
f2fc6720 | 211 | int fd; |
00e2e675 DG |
212 | struct consumer_relayd_sock_pair *relayd = NULL; |
213 | struct lttng_consumer_stream *new_stream; | |
3bd1e081 MD |
214 | |
215 | /* block */ | |
216 | if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) { | |
217 | return -EINTR; | |
218 | } | |
00e2e675 DG |
219 | |
220 | /* Get stream file descriptor from socket */ | |
f2fc6720 MD |
221 | ret = lttcomm_recv_fds_unix_sock(sock, &fd, 1); |
222 | if (ret != sizeof(fd)) { | |
3bd1e081 MD |
223 | lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD); |
224 | return ret; | |
225 | } | |
3bd1e081 | 226 | |
3bd1e081 MD |
227 | new_stream = consumer_allocate_stream(msg.u.stream.channel_key, |
228 | msg.u.stream.stream_key, | |
f2fc6720 | 229 | fd, fd, |
3bd1e081 MD |
230 | msg.u.stream.state, |
231 | msg.u.stream.mmap_len, | |
232 | msg.u.stream.output, | |
6df2e2c9 MD |
233 | msg.u.stream.path_name, |
234 | msg.u.stream.uid, | |
00e2e675 DG |
235 | msg.u.stream.gid, |
236 | msg.u.stream.net_index, | |
237 | msg.u.stream.metadata_flag); | |
3bd1e081 MD |
238 | if (new_stream == NULL) { |
239 | lttng_consumer_send_error(ctx, CONSUMERD_OUTFD_ERROR); | |
240 | goto end; | |
241 | } | |
00e2e675 DG |
242 | |
243 | /* The stream is not metadata. Get relayd reference if exists. */ | |
244 | relayd = consumer_find_relayd(msg.u.stream.net_index); | |
245 | if (relayd != NULL) { | |
246 | /* Add stream on the relayd */ | |
247 | pthread_mutex_lock(&relayd->ctrl_sock_mutex); | |
248 | ret = relayd_add_stream(&relayd->control_sock, | |
249 | msg.u.stream.name, msg.u.stream.path_name, | |
250 | &new_stream->relayd_stream_id); | |
251 | pthread_mutex_unlock(&relayd->ctrl_sock_mutex); | |
252 | if (ret < 0) { | |
253 | goto end; | |
254 | } | |
255 | } else if (msg.u.stream.net_index != -1) { | |
256 | ERR("Network sequence index %d unknown. Not adding stream.", | |
257 | msg.u.stream.net_index); | |
258 | free(new_stream); | |
259 | goto end; | |
260 | } | |
261 | ||
3bd1e081 MD |
262 | if (ctx->on_recv_stream != NULL) { |
263 | ret = ctx->on_recv_stream(new_stream); | |
264 | if (ret == 0) { | |
265 | consumer_add_stream(new_stream); | |
266 | } else if (ret < 0) { | |
267 | goto end; | |
268 | } | |
269 | } else { | |
270 | consumer_add_stream(new_stream); | |
271 | } | |
00e2e675 DG |
272 | |
273 | DBG("Kernel consumer_add_stream (%d)", fd); | |
3bd1e081 MD |
274 | break; |
275 | } | |
276 | case LTTNG_CONSUMER_UPDATE_STREAM: | |
277 | { | |
278 | if (ctx->on_update_stream != NULL) { | |
279 | ret = ctx->on_update_stream(msg.u.stream.stream_key, msg.u.stream.state); | |
280 | if (ret == 0) { | |
281 | consumer_change_stream_state(msg.u.stream.stream_key, msg.u.stream.state); | |
282 | } else if (ret < 0) { | |
283 | goto end; | |
284 | } | |
285 | } else { | |
286 | consumer_change_stream_state(msg.u.stream.stream_key, | |
287 | msg.u.stream.state); | |
288 | } | |
289 | break; | |
290 | } | |
291 | default: | |
292 | break; | |
293 | } | |
294 | end: | |
04fdd819 MD |
295 | /* |
296 | * Wake-up the other end by writing a null byte in the pipe | |
297 | * (non-blocking). Important note: Because writing into the | |
298 | * pipe is non-blocking (and therefore we allow dropping wakeup | |
299 | * data, as long as there is wakeup data present in the pipe | |
300 | * buffer to wake up the other end), the other end should | |
301 | * perform the following sequence for waiting: | |
302 | * 1) empty the pipe (reads). | |
303 | * 2) perform update operation. | |
304 | * 3) wait on the pipe (poll). | |
305 | */ | |
306 | do { | |
307 | ret = write(ctx->consumer_poll_pipe[1], "", 1); | |
6f94560a | 308 | } while (ret < 0 && errno == EINTR); |
3bd1e081 | 309 | end_nosignal: |
b0b335c8 | 310 | rcu_read_unlock(); |
3bd1e081 MD |
311 | return 0; |
312 | } | |
d41f73b7 MD |
313 | |
314 | /* | |
315 | * Consume data on a file descriptor and write it on a trace file. | |
316 | */ | |
4078b776 | 317 | ssize_t lttng_kconsumer_read_subbuffer(struct lttng_consumer_stream *stream, |
d41f73b7 MD |
318 | struct lttng_consumer_local_data *ctx) |
319 | { | |
320 | unsigned long len; | |
321 | int err; | |
4078b776 | 322 | ssize_t ret = 0; |
d41f73b7 MD |
323 | int infd = stream->wait_fd; |
324 | ||
325 | DBG("In read_subbuffer (infd : %d)", infd); | |
326 | /* Get the next subbuffer */ | |
327 | err = kernctl_get_next_subbuf(infd); | |
328 | if (err != 0) { | |
d41f73b7 MD |
329 | /* |
330 | * This is a debug message even for single-threaded consumer, | |
331 | * because poll() have more relaxed criterions than get subbuf, | |
332 | * so get_subbuf may fail for short race windows where poll() | |
333 | * would issue wakeups. | |
334 | */ | |
335 | DBG("Reserving sub buffer failed (everything is normal, " | |
336 | "it is due to concurrency)"); | |
337 | goto end; | |
338 | } | |
339 | ||
340 | switch (stream->output) { | |
341 | case LTTNG_EVENT_SPLICE: | |
342 | /* read the whole subbuffer */ | |
343 | err = kernctl_get_padded_subbuf_size(infd, &len); | |
344 | if (err != 0) { | |
87dc6a9c | 345 | errno = -ret; |
d41f73b7 MD |
346 | perror("Getting sub-buffer len failed."); |
347 | goto end; | |
348 | } | |
349 | ||
350 | /* splice the subbuffer to the tracefile */ | |
351 | ret = lttng_consumer_on_read_subbuffer_splice(ctx, stream, len); | |
47e81c02 | 352 | if (ret != len) { |
d41f73b7 MD |
353 | /* |
354 | * display the error but continue processing to try | |
355 | * to release the subbuffer | |
356 | */ | |
00e2e675 DG |
357 | ERR("Error splicing to tracefile (ret: %ld != len: %ld)", |
358 | ret, len); | |
d41f73b7 | 359 | } |
47e81c02 | 360 | |
d41f73b7 MD |
361 | break; |
362 | case LTTNG_EVENT_MMAP: | |
363 | /* read the used subbuffer size */ | |
364 | err = kernctl_get_padded_subbuf_size(infd, &len); | |
365 | if (err != 0) { | |
87dc6a9c | 366 | errno = -ret; |
d41f73b7 MD |
367 | perror("Getting sub-buffer len failed."); |
368 | goto end; | |
369 | } | |
370 | /* write the subbuffer to the tracefile */ | |
371 | ret = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, len); | |
47e81c02 | 372 | if (ret != len) { |
d41f73b7 MD |
373 | /* |
374 | * display the error but continue processing to try | |
375 | * to release the subbuffer | |
376 | */ | |
377 | ERR("Error writing to tracefile"); | |
378 | } | |
379 | break; | |
380 | default: | |
381 | ERR("Unknown output method"); | |
382 | ret = -1; | |
383 | } | |
384 | ||
385 | err = kernctl_put_next_subbuf(infd); | |
386 | if (err != 0) { | |
87dc6a9c | 387 | errno = -ret; |
d41f73b7 MD |
388 | if (errno == EFAULT) { |
389 | perror("Error in unreserving sub buffer\n"); | |
390 | } else if (errno == EIO) { | |
391 | /* Should never happen with newer LTTng versions */ | |
392 | perror("Reader has been pushed by the writer, last sub-buffer corrupted."); | |
393 | } | |
394 | goto end; | |
395 | } | |
396 | ||
397 | end: | |
398 | return ret; | |
399 | } | |
400 | ||
401 | int lttng_kconsumer_on_recv_stream(struct lttng_consumer_stream *stream) | |
402 | { | |
403 | int ret; | |
404 | ||
405 | /* Opening the tracefile in write mode */ | |
00e2e675 | 406 | if (strlen(stream->path_name) > 0 && stream->net_seq_idx == -1) { |
e11d277b | 407 | ret = run_as_open(stream->path_name, |
60b6c79c MD |
408 | O_WRONLY|O_CREAT|O_TRUNC, |
409 | S_IRWXU|S_IRWXG|S_IRWXO, | |
410 | stream->uid, stream->gid); | |
d41f73b7 MD |
411 | if (ret < 0) { |
412 | ERR("Opening %s", stream->path_name); | |
413 | perror("open"); | |
414 | goto error; | |
415 | } | |
416 | stream->out_fd = ret; | |
417 | } | |
418 | ||
419 | if (stream->output == LTTNG_EVENT_MMAP) { | |
420 | /* get the len of the mmap region */ | |
421 | unsigned long mmap_len; | |
422 | ||
423 | ret = kernctl_get_mmap_len(stream->wait_fd, &mmap_len); | |
424 | if (ret != 0) { | |
87dc6a9c | 425 | errno = -ret; |
d41f73b7 MD |
426 | perror("kernctl_get_mmap_len"); |
427 | goto error_close_fd; | |
428 | } | |
429 | stream->mmap_len = (size_t) mmap_len; | |
430 | ||
431 | stream->mmap_base = mmap(NULL, stream->mmap_len, | |
432 | PROT_READ, MAP_PRIVATE, stream->wait_fd, 0); | |
433 | if (stream->mmap_base == MAP_FAILED) { | |
434 | perror("Error mmaping"); | |
435 | ret = -1; | |
436 | goto error_close_fd; | |
437 | } | |
438 | } | |
439 | ||
440 | /* we return 0 to let the library handle the FD internally */ | |
441 | return 0; | |
442 | ||
443 | error_close_fd: | |
444 | { | |
445 | int err; | |
446 | ||
447 | err = close(stream->out_fd); | |
448 | assert(!err); | |
449 | } | |
450 | error: | |
451 | return ret; | |
452 | } | |
453 |