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> |
dbb5dfe6 | 34 | #include <common/compat/fcntl.h> |
10a8a223 DG |
35 | |
36 | #include "ust-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 | * | |
4078b776 | 45 | * Returns the number of bytes written, else negative value on error. |
3bd1e081 | 46 | */ |
4078b776 | 47 | ssize_t lttng_ustconsumer_on_read_subbuffer_mmap( |
3bd1e081 MD |
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 outfd = stream->out_fd; | |
55 | ||
56 | /* get the offset inside the fd to mmap */ | |
57 | ret = ustctl_get_mmap_read_offset(stream->chan->handle, | |
58 | stream->buf, &mmap_offset); | |
59 | if (ret != 0) { | |
87dc6a9c | 60 | errno = -ret; |
4c462e79 | 61 | PERROR("ustctl_get_mmap_read_offset"); |
3bd1e081 MD |
62 | goto end; |
63 | } | |
64 | while (len > 0) { | |
65 | ret = write(outfd, stream->mmap_base + mmap_offset, len); | |
66 | if (ret >= len) { | |
67 | len = 0; | |
68 | } else if (ret < 0) { | |
87dc6a9c | 69 | errno = -ret; |
4c462e79 | 70 | PERROR("Error in file write"); |
3bd1e081 MD |
71 | goto end; |
72 | } | |
73 | /* This won't block, but will start writeout asynchronously */ | |
dbb5dfe6 | 74 | lttng_sync_file_range(outfd, stream->out_fd_offset, ret, |
3bd1e081 MD |
75 | SYNC_FILE_RANGE_WRITE); |
76 | stream->out_fd_offset += ret; | |
77 | } | |
78 | ||
79 | lttng_consumer_sync_trace_file(stream, orig_offset); | |
80 | ||
81 | goto end; | |
82 | ||
83 | end: | |
84 | return ret; | |
85 | } | |
86 | ||
87 | /* | |
88 | * Splice the data from the ring buffer to the tracefile. | |
89 | * | |
90 | * Returns the number of bytes spliced. | |
91 | */ | |
4078b776 | 92 | ssize_t lttng_ustconsumer_on_read_subbuffer_splice( |
3bd1e081 MD |
93 | struct lttng_consumer_local_data *ctx, |
94 | struct lttng_consumer_stream *stream, unsigned long len) | |
95 | { | |
96 | return -ENOSYS; | |
97 | } | |
98 | ||
99 | /* | |
100 | * Take a snapshot for a specific fd | |
101 | * | |
102 | * Returns 0 on success, < 0 on error | |
103 | */ | |
104 | int lttng_ustconsumer_take_snapshot(struct lttng_consumer_local_data *ctx, | |
105 | struct lttng_consumer_stream *stream) | |
106 | { | |
107 | int ret = 0; | |
108 | ||
109 | ret = ustctl_snapshot(stream->chan->handle, stream->buf); | |
110 | if (ret != 0) { | |
87dc6a9c | 111 | errno = -ret; |
4c462e79 | 112 | PERROR("Getting sub-buffer snapshot."); |
3bd1e081 MD |
113 | } |
114 | ||
115 | return ret; | |
116 | } | |
117 | ||
118 | /* | |
119 | * Get the produced position | |
120 | * | |
121 | * Returns 0 on success, < 0 on error | |
122 | */ | |
123 | int lttng_ustconsumer_get_produced_snapshot( | |
124 | struct lttng_consumer_local_data *ctx, | |
125 | struct lttng_consumer_stream *stream, | |
126 | unsigned long *pos) | |
127 | { | |
128 | int ret; | |
129 | ||
130 | ret = ustctl_snapshot_get_produced(stream->chan->handle, | |
131 | stream->buf, pos); | |
132 | if (ret != 0) { | |
87dc6a9c | 133 | errno = -ret; |
4c462e79 | 134 | PERROR("kernctl_snapshot_get_produced"); |
3bd1e081 MD |
135 | } |
136 | ||
137 | return ret; | |
138 | } | |
139 | ||
140 | int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data *ctx, | |
141 | int sock, struct pollfd *consumer_sockpoll) | |
142 | { | |
143 | ssize_t ret; | |
144 | struct lttcomm_consumer_msg msg; | |
145 | ||
146 | ret = lttcomm_recv_unix_sock(sock, &msg, sizeof(msg)); | |
147 | if (ret != sizeof(msg)) { | |
148 | lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD); | |
149 | return ret; | |
150 | } | |
151 | if (msg.cmd_type == LTTNG_CONSUMER_STOP) { | |
152 | return -ENOENT; | |
153 | } | |
154 | ||
155 | switch (msg.cmd_type) { | |
156 | case LTTNG_CONSUMER_ADD_CHANNEL: | |
157 | { | |
158 | struct lttng_consumer_channel *new_channel; | |
159 | int fds[1]; | |
160 | size_t nb_fd = 1; | |
161 | ||
162 | /* block */ | |
163 | if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) { | |
164 | return -EINTR; | |
165 | } | |
166 | ret = lttcomm_recv_fds_unix_sock(sock, fds, nb_fd); | |
167 | if (ret != sizeof(fds)) { | |
168 | lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD); | |
169 | return ret; | |
170 | } | |
171 | ||
172 | DBG("consumer_add_channel %d", msg.u.channel.channel_key); | |
173 | ||
174 | new_channel = consumer_allocate_channel(msg.u.channel.channel_key, | |
175 | fds[0], -1, | |
176 | msg.u.channel.mmap_len, | |
177 | msg.u.channel.max_sb_size); | |
178 | if (new_channel == NULL) { | |
179 | lttng_consumer_send_error(ctx, CONSUMERD_OUTFD_ERROR); | |
180 | goto end_nosignal; | |
181 | } | |
182 | if (ctx->on_recv_channel != NULL) { | |
183 | ret = ctx->on_recv_channel(new_channel); | |
184 | if (ret == 0) { | |
185 | consumer_add_channel(new_channel); | |
186 | } else if (ret < 0) { | |
187 | goto end_nosignal; | |
188 | } | |
189 | } else { | |
190 | consumer_add_channel(new_channel); | |
191 | } | |
192 | goto end_nosignal; | |
193 | } | |
194 | case LTTNG_CONSUMER_ADD_STREAM: | |
195 | { | |
196 | struct lttng_consumer_stream *new_stream; | |
197 | int fds[2]; | |
198 | size_t nb_fd = 2; | |
199 | ||
200 | /* block */ | |
201 | if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) { | |
202 | return -EINTR; | |
203 | } | |
204 | ret = lttcomm_recv_fds_unix_sock(sock, fds, nb_fd); | |
205 | if (ret != sizeof(fds)) { | |
206 | lttng_consumer_send_error(ctx, CONSUMERD_ERROR_RECV_FD); | |
207 | return ret; | |
208 | } | |
209 | ||
210 | DBG("consumer_add_stream %s (%d,%d)", msg.u.stream.path_name, | |
211 | fds[0], fds[1]); | |
d41f73b7 | 212 | assert(msg.u.stream.output == LTTNG_EVENT_MMAP); |
7ad0a0cb | 213 | new_stream = consumer_allocate_stream(msg.u.channel.channel_key, |
3bd1e081 MD |
214 | msg.u.stream.stream_key, |
215 | fds[0], fds[1], | |
216 | msg.u.stream.state, | |
217 | msg.u.stream.mmap_len, | |
218 | msg.u.stream.output, | |
6df2e2c9 MD |
219 | msg.u.stream.path_name, |
220 | msg.u.stream.uid, | |
221 | msg.u.stream.gid); | |
3bd1e081 MD |
222 | if (new_stream == NULL) { |
223 | lttng_consumer_send_error(ctx, CONSUMERD_OUTFD_ERROR); | |
224 | goto end; | |
225 | } | |
226 | if (ctx->on_recv_stream != NULL) { | |
227 | ret = ctx->on_recv_stream(new_stream); | |
228 | if (ret == 0) { | |
229 | consumer_add_stream(new_stream); | |
230 | } else if (ret < 0) { | |
231 | goto end; | |
232 | } | |
233 | } else { | |
234 | consumer_add_stream(new_stream); | |
235 | } | |
236 | break; | |
237 | } | |
238 | case LTTNG_CONSUMER_UPDATE_STREAM: | |
239 | { | |
7ad0a0cb MD |
240 | return -ENOSYS; |
241 | #if 0 | |
3bd1e081 MD |
242 | if (ctx->on_update_stream != NULL) { |
243 | ret = ctx->on_update_stream(msg.u.stream.stream_key, msg.u.stream.state); | |
244 | if (ret == 0) { | |
245 | consumer_change_stream_state(msg.u.stream.stream_key, msg.u.stream.state); | |
246 | } else if (ret < 0) { | |
247 | goto end; | |
248 | } | |
249 | } else { | |
250 | consumer_change_stream_state(msg.u.stream.stream_key, | |
251 | msg.u.stream.state); | |
252 | } | |
7ad0a0cb | 253 | #endif |
3bd1e081 MD |
254 | break; |
255 | } | |
256 | default: | |
257 | break; | |
258 | } | |
259 | end: | |
5a4b955e MD |
260 | /* |
261 | * Wake-up the other end by writing a null byte in the pipe | |
262 | * (non-blocking). Important note: Because writing into the | |
263 | * pipe is non-blocking (and therefore we allow dropping wakeup | |
264 | * data, as long as there is wakeup data present in the pipe | |
265 | * buffer to wake up the other end), the other end should | |
266 | * perform the following sequence for waiting: | |
267 | * 1) empty the pipe (reads). | |
268 | * 2) perform update operation. | |
269 | * 3) wait on the pipe (poll). | |
270 | */ | |
271 | do { | |
272 | ret = write(ctx->consumer_poll_pipe[1], "", 1); | |
273 | } while (ret == -1UL && errno == EINTR); | |
3bd1e081 MD |
274 | end_nosignal: |
275 | return 0; | |
276 | } | |
277 | ||
278 | int lttng_ustconsumer_allocate_channel(struct lttng_consumer_channel *chan) | |
279 | { | |
13161846 | 280 | struct lttng_ust_object_data obj; |
3bd1e081 MD |
281 | |
282 | obj.handle = -1; | |
283 | obj.shm_fd = chan->shm_fd; | |
284 | obj.wait_fd = chan->wait_fd; | |
285 | obj.memory_map_size = chan->mmap_len; | |
286 | chan->handle = ustctl_map_channel(&obj); | |
287 | if (!chan->handle) { | |
288 | return -ENOMEM; | |
289 | } | |
b5c5fc29 | 290 | chan->wait_fd_is_copy = 1; |
2c1dd183 | 291 | chan->shm_fd = -1; |
b5c5fc29 | 292 | |
3bd1e081 MD |
293 | return 0; |
294 | } | |
295 | ||
d056b477 MD |
296 | void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream *stream) |
297 | { | |
298 | ustctl_flush_buffer(stream->chan->handle, stream->buf, 0); | |
effcf122 | 299 | stream->hangup_flush_done = 1; |
d056b477 MD |
300 | } |
301 | ||
3bd1e081 MD |
302 | void lttng_ustconsumer_del_channel(struct lttng_consumer_channel *chan) |
303 | { | |
304 | ustctl_unmap_channel(chan->handle); | |
305 | } | |
306 | ||
307 | int lttng_ustconsumer_allocate_stream(struct lttng_consumer_stream *stream) | |
308 | { | |
13161846 | 309 | struct lttng_ust_object_data obj; |
3bd1e081 MD |
310 | int ret; |
311 | ||
312 | obj.handle = -1; | |
313 | obj.shm_fd = stream->shm_fd; | |
314 | obj.wait_fd = stream->wait_fd; | |
315 | obj.memory_map_size = stream->mmap_len; | |
316 | ret = ustctl_add_stream(stream->chan->handle, &obj); | |
317 | if (ret) | |
318 | return ret; | |
319 | stream->buf = ustctl_open_stream_read(stream->chan->handle, stream->cpu); | |
320 | if (!stream->buf) | |
321 | return -EBUSY; | |
2c1dd183 MD |
322 | /* ustctl_open_stream_read has closed the shm fd. */ |
323 | stream->wait_fd_is_copy = 1; | |
324 | stream->shm_fd = -1; | |
325 | ||
3bd1e081 MD |
326 | stream->mmap_base = ustctl_get_mmap_base(stream->chan->handle, stream->buf); |
327 | if (!stream->mmap_base) { | |
328 | return -EINVAL; | |
329 | } | |
ee77a7b0 | 330 | |
3bd1e081 MD |
331 | return 0; |
332 | } | |
333 | ||
334 | void lttng_ustconsumer_del_stream(struct lttng_consumer_stream *stream) | |
335 | { | |
336 | ustctl_close_stream_read(stream->chan->handle, stream->buf); | |
337 | } | |
d41f73b7 MD |
338 | |
339 | ||
340 | int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream *stream, | |
341 | struct lttng_consumer_local_data *ctx) | |
342 | { | |
343 | unsigned long len; | |
344 | int err; | |
345 | long ret = 0; | |
346 | struct lttng_ust_shm_handle *handle; | |
347 | struct lttng_ust_lib_ring_buffer *buf; | |
348 | char dummy; | |
349 | ssize_t readlen; | |
350 | ||
351 | DBG("In read_subbuffer (wait_fd: %d, stream key: %d)", | |
352 | stream->wait_fd, stream->key); | |
353 | ||
354 | /* We can consume the 1 byte written into the wait_fd by UST */ | |
effcf122 MD |
355 | if (!stream->hangup_flush_done) { |
356 | do { | |
357 | readlen = read(stream->wait_fd, &dummy, 1); | |
87dc6a9c | 358 | } while (readlen == -1 && errno == EINTR); |
effcf122 MD |
359 | if (readlen == -1) { |
360 | ret = readlen; | |
361 | goto end; | |
362 | } | |
d41f73b7 MD |
363 | } |
364 | ||
365 | buf = stream->buf; | |
366 | handle = stream->chan->handle; | |
367 | /* Get the next subbuffer */ | |
368 | err = ustctl_get_next_subbuf(handle, buf); | |
369 | if (err != 0) { | |
effcf122 | 370 | ret = -ret; /* ustctl_get_next_subbuf returns negative, caller expect positive. */ |
d41f73b7 MD |
371 | /* |
372 | * This is a debug message even for single-threaded consumer, | |
373 | * because poll() have more relaxed criterions than get subbuf, | |
374 | * so get_subbuf may fail for short race windows where poll() | |
375 | * would issue wakeups. | |
376 | */ | |
377 | DBG("Reserving sub buffer failed (everything is normal, " | |
378 | "it is due to concurrency)"); | |
379 | goto end; | |
380 | } | |
381 | assert(stream->output == LTTNG_EVENT_MMAP); | |
382 | /* read the used subbuffer size */ | |
383 | err = ustctl_get_padded_subbuf_size(handle, buf, &len); | |
effcf122 | 384 | assert(err == 0); |
d41f73b7 MD |
385 | /* write the subbuffer to the tracefile */ |
386 | ret = lttng_consumer_on_read_subbuffer_mmap(ctx, stream, len); | |
387 | if (ret < 0) { | |
388 | /* | |
389 | * display the error but continue processing to try | |
390 | * to release the subbuffer | |
391 | */ | |
392 | ERR("Error writing to tracefile"); | |
393 | } | |
394 | err = ustctl_put_next_subbuf(handle, buf); | |
effcf122 | 395 | assert(err == 0); |
d41f73b7 MD |
396 | end: |
397 | return ret; | |
398 | } | |
399 | ||
400 | int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream *stream) | |
401 | { | |
402 | int ret; | |
403 | ||
404 | /* Opening the tracefile in write mode */ | |
405 | if (stream->path_name != NULL) { | |
e11d277b | 406 | ret = run_as_open(stream->path_name, |
60b6c79c MD |
407 | O_WRONLY|O_CREAT|O_TRUNC, |
408 | S_IRWXU|S_IRWXG|S_IRWXO, | |
409 | stream->uid, stream->gid); | |
d41f73b7 MD |
410 | if (ret < 0) { |
411 | ERR("Opening %s", stream->path_name); | |
4c462e79 | 412 | PERROR("open"); |
d41f73b7 MD |
413 | goto error; |
414 | } | |
415 | stream->out_fd = ret; | |
416 | } | |
417 | ||
418 | /* we return 0 to let the library handle the FD internally */ | |
419 | return 0; | |
420 | ||
421 | error: | |
422 | return ret; | |
423 | } |