2 * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
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.
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.
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.
21 #include <lttng/ust-ctl.h>
27 #include <sys/socket.h>
29 #include <sys/types.h>
33 #include <common/common.h>
34 #include <common/sessiond-comm/sessiond-comm.h>
35 #include <common/relayd/relayd.h>
36 #include <common/compat/fcntl.h>
38 #include "ust-consumer.h"
40 extern struct lttng_consumer_global_data consumer_data
;
41 extern int consumer_poll_timeout
;
42 extern volatile int consumer_quit
;
45 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
46 * compiled out, we isolate it in this library.
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
)
51 return ustctl_get_mmap_read_offset(handle
, buf
, off
);
55 * Take a snapshot for a specific fd
57 * Returns 0 on success, < 0 on error
59 int lttng_ustconsumer_take_snapshot(struct lttng_consumer_local_data
*ctx
,
60 struct lttng_consumer_stream
*stream
)
64 ret
= ustctl_snapshot(stream
->chan
->handle
, stream
->buf
);
67 PERROR("Getting sub-buffer snapshot.");
74 * Get the produced position
76 * Returns 0 on success, < 0 on error
78 int lttng_ustconsumer_get_produced_snapshot(
79 struct lttng_consumer_local_data
*ctx
,
80 struct lttng_consumer_stream
*stream
,
85 ret
= ustctl_snapshot_get_produced(stream
->chan
->handle
,
89 PERROR("kernctl_snapshot_get_produced");
96 * Receive command from session daemon and process it.
98 * Return 1 on success else a negative value or 0.
100 int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
101 int sock
, struct pollfd
*consumer_sockpoll
)
104 struct lttcomm_consumer_msg msg
;
106 ret
= lttcomm_recv_unix_sock(sock
, &msg
, sizeof(msg
));
107 if (ret
!= sizeof(msg
)) {
108 DBG("Consumer received unexpected message size %zd (expects %zu)",
110 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_FD
);
113 if (msg
.cmd_type
== LTTNG_CONSUMER_STOP
) {
117 /* relayd needs RCU read-side lock */
120 switch (msg
.cmd_type
) {
121 case LTTNG_CONSUMER_ADD_RELAYD_SOCKET
:
123 ret
= consumer_add_relayd_socket(msg
.u
.relayd_sock
.net_index
,
124 msg
.u
.relayd_sock
.type
, ctx
, sock
, consumer_sockpoll
,
125 &msg
.u
.relayd_sock
.sock
);
128 case LTTNG_CONSUMER_ADD_CHANNEL
:
130 struct lttng_consumer_channel
*new_channel
;
134 DBG("UST Consumer adding channel");
137 if (lttng_consumer_poll_socket(consumer_sockpoll
) < 0) {
141 ret
= lttcomm_recv_fds_unix_sock(sock
, fds
, nb_fd
);
142 if (ret
!= sizeof(fds
)) {
143 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_FD
);
148 DBG("consumer_add_channel %d", msg
.u
.channel
.channel_key
);
150 new_channel
= consumer_allocate_channel(msg
.u
.channel
.channel_key
,
152 msg
.u
.channel
.mmap_len
,
153 msg
.u
.channel
.max_sb_size
,
154 msg
.u
.channel
.nb_init_streams
);
155 if (new_channel
== NULL
) {
156 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
159 if (ctx
->on_recv_channel
!= NULL
) {
160 ret
= ctx
->on_recv_channel(new_channel
);
162 consumer_add_channel(new_channel
);
163 } else if (ret
< 0) {
167 consumer_add_channel(new_channel
);
171 case LTTNG_CONSUMER_ADD_STREAM
:
173 struct lttng_consumer_stream
*new_stream
;
176 struct consumer_relayd_sock_pair
*relayd
= NULL
;
179 DBG("UST Consumer adding stream");
182 if (lttng_consumer_poll_socket(consumer_sockpoll
) < 0) {
186 ret
= lttcomm_recv_fds_unix_sock(sock
, fds
, nb_fd
);
187 if (ret
!= sizeof(fds
)) {
188 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_FD
);
193 DBG("Consumer command ADD_STREAM chan %d stream %d",
194 msg
.u
.stream
.channel_key
, msg
.u
.stream
.stream_key
);
196 assert(msg
.u
.stream
.output
== LTTNG_EVENT_MMAP
);
197 new_stream
= consumer_allocate_stream(msg
.u
.stream
.channel_key
,
198 msg
.u
.stream
.stream_key
,
201 msg
.u
.stream
.mmap_len
,
203 msg
.u
.stream
.path_name
,
206 msg
.u
.stream
.net_index
,
207 msg
.u
.stream
.metadata_flag
,
209 if (new_stream
== NULL
) {
214 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
218 * We could not find the channel. Can happen if cpu hotplug
219 * happens while tearing down.
221 DBG3("Could not find channel");
227 /* The stream is not metadata. Get relayd reference if exists. */
228 relayd
= consumer_find_relayd(msg
.u
.stream
.net_index
);
229 if (relayd
!= NULL
) {
230 pthread_mutex_lock(&relayd
->ctrl_sock_mutex
);
231 /* Add stream on the relayd */
232 ret
= relayd_add_stream(&relayd
->control_sock
,
233 msg
.u
.stream
.name
, msg
.u
.stream
.path_name
,
234 &new_stream
->relayd_stream_id
);
235 pthread_mutex_unlock(&relayd
->ctrl_sock_mutex
);
239 } else if (msg
.u
.stream
.net_index
!= -1) {
240 ERR("Network sequence index %d unknown. Not adding stream.",
241 msg
.u
.stream
.net_index
);
246 /* Do actions once stream has been received. */
247 if (ctx
->on_recv_stream
) {
248 ret
= ctx
->on_recv_stream(new_stream
);
254 /* Send stream to the metadata thread */
255 if (new_stream
->metadata_flag
) {
257 ret
= write(ctx
->consumer_metadata_pipe
[1], &new_stream
,
259 } while (ret
< 0 && errno
== EINTR
);
261 PERROR("write metadata pipe");
264 consumer_add_stream(new_stream
);
267 DBG("UST consumer_add_stream %s (%d,%d) with relayd id %" PRIu64
,
268 msg
.u
.stream
.path_name
, fds
[0], fds
[1],
269 new_stream
->relayd_stream_id
);
272 case LTTNG_CONSUMER_DESTROY_RELAYD
:
274 uint64_t index
= msg
.u
.destroy_relayd
.net_seq_idx
;
275 struct consumer_relayd_sock_pair
*relayd
;
277 DBG("UST consumer destroying relayd %" PRIu64
, index
);
279 /* Get relayd reference if exists. */
280 relayd
= consumer_find_relayd(index
);
281 if (relayd
== NULL
) {
282 ERR("Unable to find relayd %" PRIu64
, index
);
287 * Each relayd socket pair has a refcount of stream attached to it
288 * which tells if the relayd is still active or not depending on the
291 * This will set the destroy flag of the relayd object and destroy it
292 * if the refcount reaches zero when called.
294 * The destroy can happen either here or when a stream fd hangs up.
296 consumer_flag_relayd_for_destroy(relayd
);
300 case LTTNG_CONSUMER_UPDATE_STREAM
:
305 if (ctx
->on_update_stream
!= NULL
) {
306 ret
= ctx
->on_update_stream(msg
.u
.stream
.stream_key
, msg
.u
.stream
.state
);
308 consumer_change_stream_state(msg
.u
.stream
.stream_key
, msg
.u
.stream
.state
);
309 } else if (ret
< 0) {
313 consumer_change_stream_state(msg
.u
.stream
.stream_key
,
324 * Wake-up the other end by writing a null byte in the pipe (non-blocking).
325 * Important note: Because writing into the pipe is non-blocking (and
326 * therefore we allow dropping wakeup data, as long as there is wakeup data
327 * present in the pipe buffer to wake up the other end), the other end
328 * should perform the following sequence for waiting:
330 * 1) empty the pipe (reads).
331 * 2) perform update operation.
332 * 3) wait on the pipe (poll).
335 ret
= write(ctx
->consumer_poll_pipe
[1], "", 1);
336 } while (ret
< 0 && errno
== EINTR
);
341 * Return 1 to indicate success since the 0 value can be a socket
342 * shutdown during the recv() or send() call.
347 int lttng_ustconsumer_allocate_channel(struct lttng_consumer_channel
*chan
)
349 struct lttng_ust_object_data obj
;
352 obj
.shm_fd
= chan
->shm_fd
;
353 obj
.wait_fd
= chan
->wait_fd
;
354 obj
.memory_map_size
= chan
->mmap_len
;
355 chan
->handle
= ustctl_map_channel(&obj
);
359 chan
->wait_fd_is_copy
= 1;
365 void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream
*stream
)
367 ustctl_flush_buffer(stream
->chan
->handle
, stream
->buf
, 0);
368 stream
->hangup_flush_done
= 1;
371 void lttng_ustconsumer_del_channel(struct lttng_consumer_channel
*chan
)
373 ustctl_unmap_channel(chan
->handle
);
376 int lttng_ustconsumer_allocate_stream(struct lttng_consumer_stream
*stream
)
378 struct lttng_ust_object_data obj
;
382 obj
.shm_fd
= stream
->shm_fd
;
383 obj
.wait_fd
= stream
->wait_fd
;
384 obj
.memory_map_size
= stream
->mmap_len
;
385 ret
= ustctl_add_stream(stream
->chan
->handle
, &obj
);
387 ERR("UST ctl add_stream failed with ret %d", ret
);
391 stream
->buf
= ustctl_open_stream_read(stream
->chan
->handle
, stream
->cpu
);
393 ERR("UST ctl open_stream_read failed");
397 /* ustctl_open_stream_read has closed the shm fd. */
398 stream
->wait_fd_is_copy
= 1;
401 stream
->mmap_base
= ustctl_get_mmap_base(stream
->chan
->handle
, stream
->buf
);
402 if (!stream
->mmap_base
) {
403 ERR("UST ctl get_mmap_base failed");
410 void lttng_ustconsumer_del_stream(struct lttng_consumer_stream
*stream
)
412 ustctl_close_stream_read(stream
->chan
->handle
, stream
->buf
);
416 int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
417 struct lttng_consumer_local_data
*ctx
)
419 unsigned long len
, subbuf_size
, padding
;
422 struct lttng_ust_shm_handle
*handle
;
423 struct lttng_ust_lib_ring_buffer
*buf
;
427 DBG("In read_subbuffer (wait_fd: %d, stream key: %d)",
428 stream
->wait_fd
, stream
->key
);
430 /* We can consume the 1 byte written into the wait_fd by UST */
431 if (!stream
->hangup_flush_done
) {
433 readlen
= read(stream
->wait_fd
, &dummy
, 1);
434 } while (readlen
== -1 && errno
== EINTR
);
442 handle
= stream
->chan
->handle
;
443 /* Get the next subbuffer */
444 err
= ustctl_get_next_subbuf(handle
, buf
);
446 ret
= err
; /* ustctl_get_next_subbuf returns negative, caller expect positive. */
448 * This is a debug message even for single-threaded consumer,
449 * because poll() have more relaxed criterions than get subbuf,
450 * so get_subbuf may fail for short race windows where poll()
451 * would issue wakeups.
453 DBG("Reserving sub buffer failed (everything is normal, "
454 "it is due to concurrency)");
457 assert(stream
->output
== LTTNG_EVENT_MMAP
);
458 /* Get the full padded subbuffer size */
459 err
= ustctl_get_padded_subbuf_size(handle
, buf
, &len
);
462 /* Get subbuffer data size (without padding) */
463 err
= ustctl_get_subbuf_size(handle
, buf
, &subbuf_size
);
466 /* Make sure we don't get a subbuffer size bigger than the padded */
467 assert(len
>= subbuf_size
);
469 padding
= len
- subbuf_size
;
470 /* write the subbuffer to the tracefile */
471 ret
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, subbuf_size
, padding
);
473 * The mmap operation should write subbuf_size amount of data when network
474 * streaming or the full padding (len) size when we are _not_ streaming.
476 if ((ret
!= subbuf_size
&& stream
->net_seq_idx
!= -1) ||
477 (ret
!= len
&& stream
->net_seq_idx
== -1)) {
479 * Display the error but continue processing to try to release the
482 ERR("Error writing to tracefile "
483 "(ret: %zd != len: %lu != subbuf_size: %lu)",
484 ret
, len
, subbuf_size
);
486 err
= ustctl_put_next_subbuf(handle
, buf
);
492 int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream
*stream
)
496 /* Opening the tracefile in write mode */
497 if (stream
->path_name
!= NULL
&& stream
->net_seq_idx
== -1) {
498 ret
= run_as_open(stream
->path_name
,
499 O_WRONLY
|O_CREAT
|O_TRUNC
,
500 S_IRWXU
|S_IRWXG
|S_IRWXO
,
501 stream
->uid
, stream
->gid
);
503 ERR("Opening %s", stream
->path_name
);
507 stream
->out_fd
= ret
;
510 /* we return 0 to let the library handle the FD internally */