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 | * | |
5 | * This program is free software; you can redistribute it and/or | |
6 | * modify it under the terms of the GNU General Public License | |
7 | * as published by the Free Software Foundation; only version 2 | |
8 | * of the License. | |
9 | * | |
10 | * This program is distributed in the hope that it will be useful, | |
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
13 | * GNU General Public License for more details. | |
14 | * | |
15 | * You should have received a copy of the GNU General Public License | |
16 | * along with this program; if not, write to the Free Software | |
17 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
18 | */ | |
19 | ||
20 | #define _GNU_SOURCE | |
21 | #include <assert.h> | |
22 | #include <fcntl.h> | |
23 | #include <poll.h> | |
24 | #include <pthread.h> | |
25 | #include <stdlib.h> | |
26 | #include <string.h> | |
27 | #include <sys/mman.h> | |
28 | #include <sys/socket.h> | |
29 | #include <sys/types.h> | |
30 | #include <unistd.h> | |
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> |
0857097f | 35 | |
10a8a223 | 36 | #include "kernel-consumer.h" |
3bd1e081 MD |
37 | |
38 | extern struct lttng_consumer_global_data consumer_data; | |
39 | extern int consumer_poll_timeout; | |
40 | extern volatile int consumer_quit; | |
41 | ||
42 | /* | |
43 | * Mmap the ring buffer, read it and write the data to the tracefile. | |
44 | * | |
45 | * Returns the number of bytes written | |
46 | */ | |
47 | int lttng_kconsumer_on_read_subbuffer_mmap( | |
48 | struct lttng_consumer_local_data *ctx, | |
49 | struct lttng_consumer_stream *stream, unsigned long len) | |
50 | { | |
51 | unsigned long mmap_offset; | |
52 | long ret = 0; | |
53 | off_t orig_offset = stream->out_fd_offset; | |
54 | int fd = stream->wait_fd; | |
55 | int outfd = stream->out_fd; | |
56 | ||
57 | /* get the offset inside the fd to mmap */ | |
58 | ret = kernctl_get_mmap_read_offset(fd, &mmap_offset); | |
59 | if (ret != 0) { | |
60 | ret = -errno; | |
61 | perror("kernctl_get_mmap_read_offset"); | |
62 | goto end; | |
63 | } | |
64 | ||
65 | while (len > 0) { | |
66 | ret = write(outfd, stream->mmap_base + mmap_offset, len); | |
67 | if (ret >= len) { | |
68 | len = 0; | |
69 | } else if (ret < 0) { | |
70 | ret = -errno; | |
71 | perror("Error in file write"); | |
72 | goto end; | |
73 | } | |
74 | /* This won't block, but will start writeout asynchronously */ | |
75 | sync_file_range(outfd, stream->out_fd_offset, ret, | |
76 | SYNC_FILE_RANGE_WRITE); | |
77 | stream->out_fd_offset += ret; | |
78 | } | |
79 | ||
80 | lttng_consumer_sync_trace_file(stream, orig_offset); | |
81 | ||
82 | goto end; | |
83 | ||
84 | end: | |
85 | return ret; | |
86 | } | |
87 | ||
88 | /* | |
89 | * Splice the data from the ring buffer to the tracefile. | |
90 | * | |
91 | * Returns the number of bytes spliced. | |
92 | */ | |
93 | int lttng_kconsumer_on_read_subbuffer_splice( | |
94 | struct lttng_consumer_local_data *ctx, | |
95 | struct lttng_consumer_stream *stream, unsigned long len) | |
96 | { | |
97 | long ret = 0; | |
98 | loff_t offset = 0; | |
99 | off_t orig_offset = stream->out_fd_offset; | |
100 | int fd = stream->wait_fd; | |
101 | int outfd = stream->out_fd; | |
102 | ||
103 | while (len > 0) { | |
104 | DBG("splice chan to pipe offset %lu (fd : %d)", | |
105 | (unsigned long)offset, fd); | |
106 | ret = splice(fd, &offset, ctx->consumer_thread_pipe[1], NULL, len, | |
107 | SPLICE_F_MOVE | SPLICE_F_MORE); | |
108 | DBG("splice chan to pipe ret %ld", ret); | |
109 | if (ret < 0) { | |
110 | ret = errno; | |
111 | perror("Error in relay splice"); | |
112 | goto splice_error; | |
113 | } | |
114 | ||
115 | ret = splice(ctx->consumer_thread_pipe[0], NULL, outfd, NULL, ret, | |
116 | SPLICE_F_MOVE | SPLICE_F_MORE); | |
117 | DBG("splice pipe to file %ld", ret); | |
118 | if (ret < 0) { | |
119 | ret = errno; | |
120 | perror("Error in file splice"); | |
121 | goto splice_error; | |
122 | } | |
123 | len -= ret; | |
124 | /* This won't block, but will start writeout asynchronously */ | |
125 | sync_file_range(outfd, stream->out_fd_offset, ret, | |
126 | SYNC_FILE_RANGE_WRITE); | |
127 | stream->out_fd_offset += ret; | |
128 | } | |
129 | lttng_consumer_sync_trace_file(stream, orig_offset); | |
130 | ||
131 | goto end; | |
132 | ||
133 | splice_error: | |
134 | /* send the appropriate error description to sessiond */ | |
135 | switch(ret) { | |
136 | case EBADF: | |
137 | lttng_consumer_send_error(ctx, CONSUMERD_SPLICE_EBADF); | |
138 | break; | |
139 | case EINVAL: | |
140 | lttng_consumer_send_error(ctx, CONSUMERD_SPLICE_EINVAL); | |
141 | break; | |
142 | case ENOMEM: | |
143 | lttng_consumer_send_error(ctx, CONSUMERD_SPLICE_ENOMEM); | |
144 | break; | |
145 | case ESPIPE: | |
146 | lttng_consumer_send_error(ctx, CONSUMERD_SPLICE_ESPIPE); | |
147 | break; | |
148 | } | |
149 | ||
150 | end: | |
151 | return ret; | |
152 | } | |
153 | ||
154 | /* | |
155 | * Take a snapshot for a specific fd | |
156 | * | |
157 | * Returns 0 on success, < 0 on error | |
158 | */ | |
159 | int lttng_kconsumer_take_snapshot(struct lttng_consumer_local_data *ctx, | |
160 | struct lttng_consumer_stream *stream) | |
161 | { | |
162 | int ret = 0; | |
163 | int infd = stream->wait_fd; | |
164 | ||
165 | ret = kernctl_snapshot(infd); | |
166 | if (ret != 0) { | |
167 | ret = errno; | |
168 | perror("Getting sub-buffer snapshot."); | |
169 | } | |
170 | ||
171 | return ret; | |
172 | } | |
173 | ||
174 | /* | |
175 | * Get the produced position | |
176 | * | |
177 | * Returns 0 on success, < 0 on error | |
178 | */ | |
179 | int lttng_kconsumer_get_produced_snapshot( | |
180 | struct lttng_consumer_local_data *ctx, | |
181 | struct lttng_consumer_stream *stream, | |
182 | unsigned long *pos) | |
183 | { | |
184 | int ret; | |
185 | int infd = stream->wait_fd; | |
186 | ||
187 | ret = kernctl_snapshot_get_produced(infd, pos); | |
188 | if (ret != 0) { | |
189 | ret = errno; | |
190 | perror("kernctl_snapshot_get_produced"); | |
191 | } | |
192 | ||
193 | return ret; | |
194 | } | |
195 | ||
196 | int lttng_kconsumer_recv_cmd(struct lttng_consumer_local_data *ctx, | |
197 | int sock, struct pollfd *consumer_sockpoll) | |
198 | { | |
199 | ssize_t ret; | |
200 | struct lttcomm_consumer_msg msg; | |
201 | ||
202 | ret = lttcomm_recv_unix_sock(sock, &msg, sizeof(msg)); | |
203 | if (ret != sizeof(msg)) { | |
f2fc6720 | 204 | lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_CMD); |
3bd1e081 MD |
205 | return ret; |
206 | } | |
207 | if (msg.cmd_type == LTTNG_CONSUMER_STOP) { | |
208 | return -ENOENT; | |
209 | } | |
210 | ||
211 | switch (msg.cmd_type) { | |
212 | case LTTNG_CONSUMER_ADD_CHANNEL: | |
213 | { | |
214 | struct lttng_consumer_channel *new_channel; | |
215 | ||
216 | DBG("consumer_add_channel %d", msg.u.channel.channel_key); | |
217 | new_channel = consumer_allocate_channel(msg.u.channel.channel_key, | |
218 | -1, -1, | |
219 | msg.u.channel.mmap_len, | |
220 | msg.u.channel.max_sb_size); | |
221 | if (new_channel == NULL) { | |
222 | lttng_consumer_send_error(ctx, CONSUMERD_OUTFD_ERROR); | |
223 | goto end_nosignal; | |
224 | } | |
225 | if (ctx->on_recv_channel != NULL) { | |
226 | ret = ctx->on_recv_channel(new_channel); | |
227 | if (ret == 0) { | |
228 | consumer_add_channel(new_channel); | |
229 | } else if (ret < 0) { | |
230 | goto end_nosignal; | |
231 | } | |
232 | } else { | |
233 | consumer_add_channel(new_channel); | |
234 | } | |
235 | goto end_nosignal; | |
236 | } | |
237 | case LTTNG_CONSUMER_ADD_STREAM: | |
238 | { | |
239 | struct lttng_consumer_stream *new_stream; | |
f2fc6720 | 240 | int fd; |
3bd1e081 MD |
241 | |
242 | /* block */ | |
243 | if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) { | |
244 | return -EINTR; | |
245 | } | |
f2fc6720 MD |
246 | ret = lttcomm_recv_fds_unix_sock(sock, &fd, 1); |
247 | if (ret != sizeof(fd)) { | |
3bd1e081 MD |
248 | lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD); |
249 | return ret; | |
250 | } | |
3bd1e081 | 251 | |
f2fc6720 MD |
252 | DBG("consumer_add_stream %s (%d)", msg.u.stream.path_name, |
253 | fd); | |
3bd1e081 MD |
254 | new_stream = consumer_allocate_stream(msg.u.stream.channel_key, |
255 | msg.u.stream.stream_key, | |
f2fc6720 | 256 | fd, fd, |
3bd1e081 MD |
257 | msg.u.stream.state, |
258 | msg.u.stream.mmap_len, | |
259 | msg.u.stream.output, | |
6df2e2c9 MD |
260 | msg.u.stream.path_name, |
261 | msg.u.stream.uid, | |
262 | msg.u.stream.gid); | |
3bd1e081 MD |
263 | if (new_stream == NULL) { |
264 | lttng_consumer_send_error(ctx, CONSUMERD_OUTFD_ERROR); | |
265 | goto end; | |
266 | } | |
267 | if (ctx->on_recv_stream != NULL) { | |
268 | ret = ctx->on_recv_stream(new_stream); | |
269 | if (ret == 0) { | |
270 | consumer_add_stream(new_stream); | |
271 | } else if (ret < 0) { | |
272 | goto end; | |
273 | } | |
274 | } else { | |
275 | consumer_add_stream(new_stream); | |
276 | } | |
277 | break; | |
278 | } | |
279 | case LTTNG_CONSUMER_UPDATE_STREAM: | |
280 | { | |
281 | if (ctx->on_update_stream != NULL) { | |
282 | ret = ctx->on_update_stream(msg.u.stream.stream_key, msg.u.stream.state); | |
283 | if (ret == 0) { | |
284 | consumer_change_stream_state(msg.u.stream.stream_key, msg.u.stream.state); | |
285 | } else if (ret < 0) { | |
286 | goto end; | |
287 | } | |
288 | } else { | |
289 | consumer_change_stream_state(msg.u.stream.stream_key, | |
290 | msg.u.stream.state); | |
291 | } | |
292 | break; | |
293 | } | |
294 | default: | |
295 | break; | |
296 | } | |
297 | end: | |
298 | /* signal the poll thread */ | |
299 | ret = write(ctx->consumer_poll_pipe[1], "4", 1); | |
300 | if (ret < 0) { | |
301 | perror("write consumer poll"); | |
302 | } | |
303 | end_nosignal: | |
304 | return 0; | |
305 | } | |
d41f73b7 MD |
306 | |
307 | /* | |
308 | * Consume data on a file descriptor and write it on a trace file. | |
309 | */ | |
310 | int lttng_kconsumer_read_subbuffer(struct lttng_consumer_stream *stream, | |
311 | struct lttng_consumer_local_data *ctx) | |
312 | { | |
313 | unsigned long len; | |
314 | int err; | |
315 | long ret = 0; | |
316 | int infd = stream->wait_fd; | |
317 | ||
318 | DBG("In read_subbuffer (infd : %d)", infd); | |
319 | /* Get the next subbuffer */ | |
320 | err = kernctl_get_next_subbuf(infd); | |
321 | if (err != 0) { | |
322 | ret = errno; | |
323 | /* | |
324 | * This is a debug message even for single-threaded consumer, | |
325 | * because poll() have more relaxed criterions than get subbuf, | |
326 | * so get_subbuf may fail for short race windows where poll() | |
327 | * would issue wakeups. | |
328 | */ | |
329 | DBG("Reserving sub buffer failed (everything is normal, " | |
330 | "it is due to concurrency)"); | |
331 | goto end; | |
332 | } | |
333 | ||
334 | switch (stream->output) { | |
335 | case LTTNG_EVENT_SPLICE: | |
336 | /* read the whole subbuffer */ | |
337 | err = kernctl_get_padded_subbuf_size(infd, &len); | |
338 | if (err != 0) { | |
339 | ret = errno; | |
340 | perror("Getting sub-buffer len failed."); | |
341 | goto end; | |
342 | } | |
343 | ||
344 | /* splice the subbuffer to the tracefile */ | |
345 | ret = lttng_consumer_on_read_subbuffer_splice(ctx, stream, len); | |
346 | if (ret < 0) { | |
347 | /* | |
348 | * display the error but continue processing to try | |
349 | * to release the subbuffer | |
350 | */ | |
351 | ERR("Error splicing to tracefile"); | |
352 | } | |
353 | break; | |
354 | case LTTNG_EVENT_MMAP: | |
355 | /* read the used subbuffer size */ | |
356 | err = kernctl_get_padded_subbuf_size(infd, &len); | |
357 | if (err != 0) { | |
358 | ret = errno; | |
359 | perror("Getting sub-buffer len failed."); | |
360 | goto end; | |
361 | } | |
362 | /* write the subbuffer to the tracefile */ | |
363 | ret = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, len); | |
364 | if (ret < 0) { | |
365 | /* | |
366 | * display the error but continue processing to try | |
367 | * to release the subbuffer | |
368 | */ | |
369 | ERR("Error writing to tracefile"); | |
370 | } | |
371 | break; | |
372 | default: | |
373 | ERR("Unknown output method"); | |
374 | ret = -1; | |
375 | } | |
376 | ||
377 | err = kernctl_put_next_subbuf(infd); | |
378 | if (err != 0) { | |
379 | ret = errno; | |
380 | if (errno == EFAULT) { | |
381 | perror("Error in unreserving sub buffer\n"); | |
382 | } else if (errno == EIO) { | |
383 | /* Should never happen with newer LTTng versions */ | |
384 | perror("Reader has been pushed by the writer, last sub-buffer corrupted."); | |
385 | } | |
386 | goto end; | |
387 | } | |
388 | ||
389 | end: | |
390 | return ret; | |
391 | } | |
392 | ||
393 | int lttng_kconsumer_on_recv_stream(struct lttng_consumer_stream *stream) | |
394 | { | |
395 | int ret; | |
396 | ||
397 | /* Opening the tracefile in write mode */ | |
398 | if (stream->path_name != NULL) { | |
e11d277b | 399 | ret = run_as_open(stream->path_name, |
60b6c79c MD |
400 | O_WRONLY|O_CREAT|O_TRUNC, |
401 | S_IRWXU|S_IRWXG|S_IRWXO, | |
402 | stream->uid, stream->gid); | |
d41f73b7 MD |
403 | if (ret < 0) { |
404 | ERR("Opening %s", stream->path_name); | |
405 | perror("open"); | |
406 | goto error; | |
407 | } | |
408 | stream->out_fd = ret; | |
409 | } | |
410 | ||
411 | if (stream->output == LTTNG_EVENT_MMAP) { | |
412 | /* get the len of the mmap region */ | |
413 | unsigned long mmap_len; | |
414 | ||
415 | ret = kernctl_get_mmap_len(stream->wait_fd, &mmap_len); | |
416 | if (ret != 0) { | |
417 | ret = errno; | |
418 | perror("kernctl_get_mmap_len"); | |
419 | goto error_close_fd; | |
420 | } | |
421 | stream->mmap_len = (size_t) mmap_len; | |
422 | ||
423 | stream->mmap_base = mmap(NULL, stream->mmap_len, | |
424 | PROT_READ, MAP_PRIVATE, stream->wait_fd, 0); | |
425 | if (stream->mmap_base == MAP_FAILED) { | |
426 | perror("Error mmaping"); | |
427 | ret = -1; | |
428 | goto error_close_fd; | |
429 | } | |
430 | } | |
431 | ||
432 | /* we return 0 to let the library handle the FD internally */ | |
433 | return 0; | |
434 | ||
435 | error_close_fd: | |
436 | { | |
437 | int err; | |
438 | ||
439 | err = close(stream->out_fd); | |
440 | assert(!err); | |
441 | } | |
442 | error: | |
443 | return ret; | |
444 | } | |
445 |