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
;
174 int fds
[2], stream_pipe
;
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
,
208 msg
.u
.stream
.session_id
,
210 if (new_stream
== NULL
) {
215 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
219 * We could not find the channel. Can happen if cpu hotplug
220 * happens while tearing down.
222 DBG3("Could not find channel");
228 /* The stream is not metadata. Get relayd reference if exists. */
229 relayd
= consumer_find_relayd(msg
.u
.stream
.net_index
);
230 if (relayd
!= NULL
) {
231 pthread_mutex_lock(&relayd
->ctrl_sock_mutex
);
232 /* Add stream on the relayd */
233 ret
= relayd_add_stream(&relayd
->control_sock
,
234 msg
.u
.stream
.name
, msg
.u
.stream
.path_name
,
235 &new_stream
->relayd_stream_id
);
236 pthread_mutex_unlock(&relayd
->ctrl_sock_mutex
);
238 consumer_del_stream(new_stream
, NULL
);
241 } else if (msg
.u
.stream
.net_index
!= -1) {
242 ERR("Network sequence index %d unknown. Not adding stream.",
243 msg
.u
.stream
.net_index
);
244 consumer_del_stream(new_stream
, NULL
);
248 /* Do actions once stream has been received. */
249 if (ctx
->on_recv_stream
) {
250 ret
= ctx
->on_recv_stream(new_stream
);
252 consumer_del_stream(new_stream
, NULL
);
257 /* Get the right pipe where the stream will be sent. */
258 if (new_stream
->metadata_flag
) {
259 stream_pipe
= ctx
->consumer_metadata_pipe
[1];
261 stream_pipe
= ctx
->consumer_data_pipe
[1];
265 ret
= write(stream_pipe
, &new_stream
, sizeof(new_stream
));
266 } while (ret
< 0 && errno
== EINTR
);
268 PERROR("Consumer write %s stream to pipe %d",
269 new_stream
->metadata_flag
? "metadata" : "data",
271 consumer_del_stream(new_stream
, NULL
);
275 DBG("UST consumer ADD_STREAM %s (%d,%d) with relayd id %" PRIu64
,
276 msg
.u
.stream
.path_name
, fds
[0], fds
[1],
277 new_stream
->relayd_stream_id
);
280 case LTTNG_CONSUMER_DESTROY_RELAYD
:
282 uint64_t index
= msg
.u
.destroy_relayd
.net_seq_idx
;
283 struct consumer_relayd_sock_pair
*relayd
;
285 DBG("UST consumer destroying relayd %" PRIu64
, index
);
287 /* Get relayd reference if exists. */
288 relayd
= consumer_find_relayd(index
);
289 if (relayd
== NULL
) {
290 ERR("Unable to find relayd %" PRIu64
, index
);
295 * Each relayd socket pair has a refcount of stream attached to it
296 * which tells if the relayd is still active or not depending on the
299 * This will set the destroy flag of the relayd object and destroy it
300 * if the refcount reaches zero when called.
302 * The destroy can happen either here or when a stream fd hangs up.
304 consumer_flag_relayd_for_destroy(relayd
);
308 case LTTNG_CONSUMER_UPDATE_STREAM
:
313 case LTTNG_CONSUMER_DATA_AVAILABLE
:
316 uint64_t id
= msg
.u
.data_available
.session_id
;
318 DBG("UST consumer data available command for id %" PRIu64
, id
);
320 ret
= consumer_data_available(id
);
322 /* Send back returned value to session daemon */
323 ret
= lttcomm_send_unix_sock(sock
, &ret
, sizeof(ret
));
325 PERROR("send data available ret code");
337 * Return 1 to indicate success since the 0 value can be a socket
338 * shutdown during the recv() or send() call.
343 int lttng_ustconsumer_allocate_channel(struct lttng_consumer_channel
*chan
)
345 struct lttng_ust_object_data obj
;
348 obj
.shm_fd
= chan
->shm_fd
;
349 obj
.wait_fd
= chan
->wait_fd
;
350 obj
.memory_map_size
= chan
->mmap_len
;
351 chan
->handle
= ustctl_map_channel(&obj
);
355 chan
->wait_fd_is_copy
= 1;
361 void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream
*stream
)
363 ustctl_flush_buffer(stream
->chan
->handle
, stream
->buf
, 0);
364 stream
->hangup_flush_done
= 1;
367 void lttng_ustconsumer_del_channel(struct lttng_consumer_channel
*chan
)
369 ustctl_unmap_channel(chan
->handle
);
372 int lttng_ustconsumer_add_stream(struct lttng_consumer_stream
*stream
)
374 struct lttng_ust_object_data obj
;
378 obj
.shm_fd
= stream
->shm_fd
;
379 obj
.wait_fd
= stream
->wait_fd
;
380 obj
.memory_map_size
= stream
->mmap_len
;
381 ret
= ustctl_add_stream(stream
->chan
->handle
, &obj
);
383 ERR("UST ctl add_stream failed with ret %d", ret
);
387 stream
->buf
= ustctl_open_stream_read(stream
->chan
->handle
, stream
->cpu
);
389 ERR("UST ctl open_stream_read failed");
394 /* ustctl_open_stream_read has closed the shm fd. */
395 stream
->wait_fd_is_copy
= 1;
398 stream
->mmap_base
= ustctl_get_mmap_base(stream
->chan
->handle
, stream
->buf
);
399 if (!stream
->mmap_base
) {
400 ERR("UST ctl get_mmap_base failed");
408 ustctl_close_stream_read(stream
->chan
->handle
, stream
->buf
);
413 void lttng_ustconsumer_del_stream(struct lttng_consumer_stream
*stream
)
415 ustctl_close_stream_read(stream
->chan
->handle
, stream
->buf
);
419 int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
420 struct lttng_consumer_local_data
*ctx
)
422 unsigned long len
, subbuf_size
, padding
;
425 struct lttng_ust_shm_handle
*handle
;
426 struct lttng_ust_lib_ring_buffer
*buf
;
430 DBG("In read_subbuffer (wait_fd: %d, stream key: %d)",
431 stream
->wait_fd
, stream
->key
);
433 /* We can consume the 1 byte written into the wait_fd by UST */
434 if (!stream
->hangup_flush_done
) {
436 readlen
= read(stream
->wait_fd
, &dummy
, 1);
437 } while (readlen
== -1 && errno
== EINTR
);
445 handle
= stream
->chan
->handle
;
446 /* Get the next subbuffer */
447 err
= ustctl_get_next_subbuf(handle
, buf
);
449 ret
= err
; /* ustctl_get_next_subbuf returns negative, caller expect positive. */
451 * This is a debug message even for single-threaded consumer,
452 * because poll() have more relaxed criterions than get subbuf,
453 * so get_subbuf may fail for short race windows where poll()
454 * would issue wakeups.
456 DBG("Reserving sub buffer failed (everything is normal, "
457 "it is due to concurrency)");
460 assert(stream
->output
== LTTNG_EVENT_MMAP
);
461 /* Get the full padded subbuffer size */
462 err
= ustctl_get_padded_subbuf_size(handle
, buf
, &len
);
465 /* Get subbuffer data size (without padding) */
466 err
= ustctl_get_subbuf_size(handle
, buf
, &subbuf_size
);
469 /* Make sure we don't get a subbuffer size bigger than the padded */
470 assert(len
>= subbuf_size
);
472 padding
= len
- subbuf_size
;
473 /* write the subbuffer to the tracefile */
474 ret
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, subbuf_size
, padding
);
476 * The mmap operation should write subbuf_size amount of data when network
477 * streaming or the full padding (len) size when we are _not_ streaming.
479 if ((ret
!= subbuf_size
&& stream
->net_seq_idx
!= -1) ||
480 (ret
!= len
&& stream
->net_seq_idx
== -1)) {
482 * Display the error but continue processing to try to release the
485 ERR("Error writing to tracefile "
486 "(ret: %zd != len: %lu != subbuf_size: %lu)",
487 ret
, len
, subbuf_size
);
489 err
= ustctl_put_next_subbuf(handle
, buf
);
495 int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream
*stream
)
499 /* Opening the tracefile in write mode */
500 if (stream
->path_name
!= NULL
&& stream
->net_seq_idx
== -1) {
501 ret
= run_as_open(stream
->path_name
,
502 O_WRONLY
|O_CREAT
|O_TRUNC
,
503 S_IRWXU
|S_IRWXG
|S_IRWXO
,
504 stream
->uid
, stream
->gid
);
506 ERR("Opening %s", stream
->path_name
);
510 stream
->out_fd
= ret
;
513 ret
= lttng_ustconsumer_add_stream(stream
);
515 consumer_del_stream(stream
, NULL
);
520 /* we return 0 to let the library handle the FD internally */
528 * Check if data is still being extracted from the buffers for a specific
529 * stream. Consumer data lock MUST be acquired before calling this function.
531 * Return 0 if the traced data are still getting read else 1 meaning that the
532 * data is available for trace viewer reading.
534 int lttng_ustconsumer_data_available(struct lttng_consumer_stream
*stream
)
540 DBG("UST consumer checking data availability");
543 * Try to lock the stream mutex. On failure, we know that the stream is
544 * being used else where hence there is data still being extracted.
546 ret
= pthread_mutex_trylock(&stream
->lock
);
548 goto data_not_available
;
550 /* The stream is now locked so we can do our ustctl calls */
552 ret
= ustctl_get_next_subbuf(stream
->chan
->handle
, stream
->buf
);
554 /* There is still data so let's put back this subbuffer. */
555 ret
= ustctl_put_subbuf(stream
->chan
->handle
, stream
->buf
);
557 pthread_mutex_unlock(&stream
->lock
);
558 goto data_not_available
;
561 /* Data is available to be read for this stream. */
562 pthread_mutex_unlock(&stream
->lock
);