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 | */ | |
50 | int lttng_kconsumer_take_snapshot(struct lttng_consumer_local_data *ctx, | |
51 | struct lttng_consumer_stream *stream) | |
52 | { | |
53 | int ret = 0; | |
54 | int infd = stream->wait_fd; | |
55 | ||
56 | ret = kernctl_snapshot(infd); | |
57 | if (ret != 0) { | |
87dc6a9c | 58 | errno = -ret; |
3bd1e081 MD |
59 | perror("Getting sub-buffer snapshot."); |
60 | } | |
61 | ||
62 | return ret; | |
63 | } | |
64 | ||
65 | /* | |
66 | * Get the produced position | |
67 | * | |
68 | * Returns 0 on success, < 0 on error | |
69 | */ | |
70 | int lttng_kconsumer_get_produced_snapshot( | |
71 | struct lttng_consumer_local_data *ctx, | |
72 | struct lttng_consumer_stream *stream, | |
73 | unsigned long *pos) | |
74 | { | |
75 | int ret; | |
76 | int infd = stream->wait_fd; | |
77 | ||
78 | ret = kernctl_snapshot_get_produced(infd, pos); | |
79 | if (ret != 0) { | |
87dc6a9c | 80 | errno = -ret; |
3bd1e081 MD |
81 | perror("kernctl_snapshot_get_produced"); |
82 | } | |
83 | ||
84 | return ret; | |
85 | } | |
86 | ||
87 | int lttng_kconsumer_recv_cmd(struct lttng_consumer_local_data *ctx, | |
88 | int sock, struct pollfd *consumer_sockpoll) | |
89 | { | |
90 | ssize_t ret; | |
91 | struct lttcomm_consumer_msg msg; | |
92 | ||
93 | ret = lttcomm_recv_unix_sock(sock, &msg, sizeof(msg)); | |
94 | if (ret != sizeof(msg)) { | |
f73fabfd | 95 | lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_ERROR_RECV_CMD); |
3bd1e081 MD |
96 | return ret; |
97 | } | |
98 | if (msg.cmd_type == LTTNG_CONSUMER_STOP) { | |
99 | return -ENOENT; | |
100 | } | |
101 | ||
b0b335c8 MD |
102 | /* relayd needs RCU read-side protection */ |
103 | rcu_read_lock(); | |
104 | ||
3bd1e081 | 105 | switch (msg.cmd_type) { |
00e2e675 DG |
106 | case LTTNG_CONSUMER_ADD_RELAYD_SOCKET: |
107 | { | |
7735ef9e DG |
108 | ret = consumer_add_relayd_socket(msg.u.relayd_sock.net_index, |
109 | msg.u.relayd_sock.type, ctx, sock, consumer_sockpoll, | |
110 | &msg.u.relayd_sock.sock); | |
00e2e675 DG |
111 | goto end_nosignal; |
112 | } | |
3bd1e081 MD |
113 | case LTTNG_CONSUMER_ADD_CHANNEL: |
114 | { | |
115 | struct lttng_consumer_channel *new_channel; | |
116 | ||
117 | DBG("consumer_add_channel %d", msg.u.channel.channel_key); | |
118 | new_channel = consumer_allocate_channel(msg.u.channel.channel_key, | |
119 | -1, -1, | |
120 | msg.u.channel.mmap_len, | |
121 | msg.u.channel.max_sb_size); | |
122 | if (new_channel == NULL) { | |
f73fabfd | 123 | lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_OUTFD_ERROR); |
3bd1e081 MD |
124 | goto end_nosignal; |
125 | } | |
126 | if (ctx->on_recv_channel != NULL) { | |
127 | ret = ctx->on_recv_channel(new_channel); | |
128 | if (ret == 0) { | |
129 | consumer_add_channel(new_channel); | |
130 | } else if (ret < 0) { | |
131 | goto end_nosignal; | |
132 | } | |
133 | } else { | |
134 | consumer_add_channel(new_channel); | |
135 | } | |
136 | goto end_nosignal; | |
137 | } | |
138 | case LTTNG_CONSUMER_ADD_STREAM: | |
139 | { | |
f2fc6720 | 140 | int fd; |
00e2e675 DG |
141 | struct consumer_relayd_sock_pair *relayd = NULL; |
142 | struct lttng_consumer_stream *new_stream; | |
3bd1e081 MD |
143 | |
144 | /* block */ | |
145 | if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) { | |
3f8e211f | 146 | rcu_read_unlock(); |
3bd1e081 MD |
147 | return -EINTR; |
148 | } | |
00e2e675 DG |
149 | |
150 | /* Get stream file descriptor from socket */ | |
f2fc6720 MD |
151 | ret = lttcomm_recv_fds_unix_sock(sock, &fd, 1); |
152 | if (ret != sizeof(fd)) { | |
f73fabfd | 153 | lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_ERROR_RECV_FD); |
3f8e211f | 154 | rcu_read_unlock(); |
3bd1e081 MD |
155 | return ret; |
156 | } | |
3bd1e081 | 157 | |
3bd1e081 MD |
158 | new_stream = consumer_allocate_stream(msg.u.stream.channel_key, |
159 | msg.u.stream.stream_key, | |
f2fc6720 | 160 | fd, fd, |
3bd1e081 MD |
161 | msg.u.stream.state, |
162 | msg.u.stream.mmap_len, | |
163 | msg.u.stream.output, | |
6df2e2c9 MD |
164 | msg.u.stream.path_name, |
165 | msg.u.stream.uid, | |
00e2e675 DG |
166 | msg.u.stream.gid, |
167 | msg.u.stream.net_index, | |
168 | msg.u.stream.metadata_flag); | |
3bd1e081 | 169 | if (new_stream == NULL) { |
f73fabfd | 170 | lttng_consumer_send_error(ctx, LTTCOMM_CONSUMERD_OUTFD_ERROR); |
3f8e211f | 171 | goto end_nosignal; |
3bd1e081 | 172 | } |
00e2e675 DG |
173 | |
174 | /* The stream is not metadata. Get relayd reference if exists. */ | |
175 | relayd = consumer_find_relayd(msg.u.stream.net_index); | |
176 | if (relayd != NULL) { | |
177 | /* Add stream on the relayd */ | |
178 | pthread_mutex_lock(&relayd->ctrl_sock_mutex); | |
179 | ret = relayd_add_stream(&relayd->control_sock, | |
180 | msg.u.stream.name, msg.u.stream.path_name, | |
181 | &new_stream->relayd_stream_id); | |
182 | pthread_mutex_unlock(&relayd->ctrl_sock_mutex); | |
183 | if (ret < 0) { | |
3f8e211f | 184 | goto end_nosignal; |
00e2e675 DG |
185 | } |
186 | } else if (msg.u.stream.net_index != -1) { | |
187 | ERR("Network sequence index %d unknown. Not adding stream.", | |
188 | msg.u.stream.net_index); | |
189 | free(new_stream); | |
3f8e211f | 190 | goto end_nosignal; |
00e2e675 DG |
191 | } |
192 | ||
3bd1e081 MD |
193 | if (ctx->on_recv_stream != NULL) { |
194 | ret = ctx->on_recv_stream(new_stream); | |
195 | if (ret == 0) { | |
196 | consumer_add_stream(new_stream); | |
197 | } else if (ret < 0) { | |
3f8e211f | 198 | goto end_nosignal; |
3bd1e081 MD |
199 | } |
200 | } else { | |
201 | consumer_add_stream(new_stream); | |
202 | } | |
00e2e675 DG |
203 | |
204 | DBG("Kernel consumer_add_stream (%d)", fd); | |
3bd1e081 MD |
205 | break; |
206 | } | |
207 | case LTTNG_CONSUMER_UPDATE_STREAM: | |
208 | { | |
3f8e211f DG |
209 | rcu_read_unlock(); |
210 | return -ENOSYS; | |
211 | } | |
212 | case LTTNG_CONSUMER_DESTROY_RELAYD: | |
213 | { | |
a6ba4fe1 | 214 | uint64_t index = msg.u.destroy_relayd.net_seq_idx; |
3f8e211f DG |
215 | struct consumer_relayd_sock_pair *relayd; |
216 | ||
a6ba4fe1 | 217 | DBG("Kernel consumer destroying relayd %" PRIu64, index); |
3f8e211f DG |
218 | |
219 | /* Get relayd reference if exists. */ | |
a6ba4fe1 | 220 | relayd = consumer_find_relayd(index); |
3f8e211f | 221 | if (relayd == NULL) { |
a6ba4fe1 | 222 | ERR("Unable to find relayd %" PRIu64, index); |
3f8e211f | 223 | goto end_nosignal; |
3bd1e081 | 224 | } |
3f8e211f | 225 | |
a6ba4fe1 DG |
226 | /* |
227 | * Each relayd socket pair has a refcount of stream attached to it | |
228 | * which tells if the relayd is still active or not depending on the | |
229 | * refcount value. | |
230 | * | |
231 | * This will set the destroy flag of the relayd object and destroy it | |
232 | * if the refcount reaches zero when called. | |
233 | * | |
234 | * The destroy can happen either here or when a stream fd hangs up. | |
235 | */ | |
236 | consumer_flag_relayd_for_destroy(relayd); | |
3f8e211f | 237 | |
3f8e211f | 238 | goto end_nosignal; |
3bd1e081 MD |
239 | } |
240 | default: | |
3f8e211f | 241 | goto end_nosignal; |
3bd1e081 | 242 | } |
3f8e211f | 243 | |
04fdd819 | 244 | /* |
3f8e211f DG |
245 | * Wake-up the other end by writing a null byte in the pipe (non-blocking). |
246 | * Important note: Because writing into the pipe is non-blocking (and | |
247 | * therefore we allow dropping wakeup data, as long as there is wakeup data | |
248 | * present in the pipe buffer to wake up the other end), the other end | |
249 | * should perform the following sequence for waiting: | |
250 | * | |
04fdd819 MD |
251 | * 1) empty the pipe (reads). |
252 | * 2) perform update operation. | |
253 | * 3) wait on the pipe (poll). | |
254 | */ | |
255 | do { | |
256 | ret = write(ctx->consumer_poll_pipe[1], "", 1); | |
6f94560a | 257 | } while (ret < 0 && errno == EINTR); |
3bd1e081 | 258 | end_nosignal: |
b0b335c8 | 259 | rcu_read_unlock(); |
3bd1e081 MD |
260 | return 0; |
261 | } | |
d41f73b7 MD |
262 | |
263 | /* | |
264 | * Consume data on a file descriptor and write it on a trace file. | |
265 | */ | |
4078b776 | 266 | ssize_t lttng_kconsumer_read_subbuffer(struct lttng_consumer_stream *stream, |
d41f73b7 MD |
267 | struct lttng_consumer_local_data *ctx) |
268 | { | |
269 | unsigned long len; | |
270 | int err; | |
4078b776 | 271 | ssize_t ret = 0; |
d41f73b7 MD |
272 | int infd = stream->wait_fd; |
273 | ||
274 | DBG("In read_subbuffer (infd : %d)", infd); | |
275 | /* Get the next subbuffer */ | |
276 | err = kernctl_get_next_subbuf(infd); | |
277 | if (err != 0) { | |
d41f73b7 MD |
278 | /* |
279 | * This is a debug message even for single-threaded consumer, | |
280 | * because poll() have more relaxed criterions than get subbuf, | |
281 | * so get_subbuf may fail for short race windows where poll() | |
282 | * would issue wakeups. | |
283 | */ | |
284 | DBG("Reserving sub buffer failed (everything is normal, " | |
285 | "it is due to concurrency)"); | |
286 | goto end; | |
287 | } | |
288 | ||
289 | switch (stream->output) { | |
290 | case LTTNG_EVENT_SPLICE: | |
291 | /* read the whole subbuffer */ | |
292 | err = kernctl_get_padded_subbuf_size(infd, &len); | |
293 | if (err != 0) { | |
87dc6a9c | 294 | errno = -ret; |
d41f73b7 MD |
295 | perror("Getting sub-buffer len failed."); |
296 | goto end; | |
297 | } | |
298 | ||
299 | /* splice the subbuffer to the tracefile */ | |
300 | ret = lttng_consumer_on_read_subbuffer_splice(ctx, stream, len); | |
47e81c02 | 301 | if (ret != len) { |
d41f73b7 MD |
302 | /* |
303 | * display the error but continue processing to try | |
304 | * to release the subbuffer | |
305 | */ | |
77c7c900 | 306 | ERR("Error splicing to tracefile (ret: %zd != len: %lu)", |
00e2e675 | 307 | ret, len); |
d41f73b7 | 308 | } |
47e81c02 | 309 | |
d41f73b7 MD |
310 | break; |
311 | case LTTNG_EVENT_MMAP: | |
312 | /* read the used subbuffer size */ | |
313 | err = kernctl_get_padded_subbuf_size(infd, &len); | |
314 | if (err != 0) { | |
87dc6a9c | 315 | errno = -ret; |
d41f73b7 MD |
316 | perror("Getting sub-buffer len failed."); |
317 | goto end; | |
318 | } | |
319 | /* write the subbuffer to the tracefile */ | |
320 | ret = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, len); | |
47e81c02 | 321 | if (ret != len) { |
d41f73b7 MD |
322 | /* |
323 | * display the error but continue processing to try | |
324 | * to release the subbuffer | |
325 | */ | |
326 | ERR("Error writing to tracefile"); | |
327 | } | |
328 | break; | |
329 | default: | |
330 | ERR("Unknown output method"); | |
331 | ret = -1; | |
332 | } | |
333 | ||
334 | err = kernctl_put_next_subbuf(infd); | |
335 | if (err != 0) { | |
87dc6a9c | 336 | errno = -ret; |
d41f73b7 MD |
337 | if (errno == EFAULT) { |
338 | perror("Error in unreserving sub buffer\n"); | |
339 | } else if (errno == EIO) { | |
340 | /* Should never happen with newer LTTng versions */ | |
341 | perror("Reader has been pushed by the writer, last sub-buffer corrupted."); | |
342 | } | |
343 | goto end; | |
344 | } | |
345 | ||
346 | end: | |
347 | return ret; | |
348 | } | |
349 | ||
350 | int lttng_kconsumer_on_recv_stream(struct lttng_consumer_stream *stream) | |
351 | { | |
352 | int ret; | |
353 | ||
354 | /* Opening the tracefile in write mode */ | |
00e2e675 | 355 | if (strlen(stream->path_name) > 0 && stream->net_seq_idx == -1) { |
e11d277b | 356 | ret = run_as_open(stream->path_name, |
60b6c79c MD |
357 | O_WRONLY|O_CREAT|O_TRUNC, |
358 | S_IRWXU|S_IRWXG|S_IRWXO, | |
359 | stream->uid, stream->gid); | |
d41f73b7 MD |
360 | if (ret < 0) { |
361 | ERR("Opening %s", stream->path_name); | |
362 | perror("open"); | |
363 | goto error; | |
364 | } | |
365 | stream->out_fd = ret; | |
366 | } | |
367 | ||
368 | if (stream->output == LTTNG_EVENT_MMAP) { | |
369 | /* get the len of the mmap region */ | |
370 | unsigned long mmap_len; | |
371 | ||
372 | ret = kernctl_get_mmap_len(stream->wait_fd, &mmap_len); | |
373 | if (ret != 0) { | |
87dc6a9c | 374 | errno = -ret; |
d41f73b7 MD |
375 | perror("kernctl_get_mmap_len"); |
376 | goto error_close_fd; | |
377 | } | |
378 | stream->mmap_len = (size_t) mmap_len; | |
379 | ||
380 | stream->mmap_base = mmap(NULL, stream->mmap_len, | |
381 | PROT_READ, MAP_PRIVATE, stream->wait_fd, 0); | |
382 | if (stream->mmap_base == MAP_FAILED) { | |
383 | perror("Error mmaping"); | |
384 | ret = -1; | |
385 | goto error_close_fd; | |
386 | } | |
387 | } | |
388 | ||
389 | /* we return 0 to let the library handle the FD internally */ | |
390 | return 0; | |
391 | ||
392 | error_close_fd: | |
393 | { | |
394 | int err; | |
395 | ||
396 | err = close(stream->out_fd); | |
397 | assert(!err); | |
398 | } | |
399 | error: | |
400 | return ret; | |
401 | } | |
402 |