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, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
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.
26 #include <sys/socket.h>
27 #include <sys/types.h>
30 #include <common/common.h>
31 #include <common/kernel-ctl/kernel-ctl.h>
32 #include <common/sessiond-comm/sessiond-comm.h>
33 #include <common/kernel-consumer/kernel-consumer.h>
34 #include <common/ust-consumer/ust-consumer.h>
38 struct lttng_consumer_global_data consumer_data
= {
41 .type
= LTTNG_CONSUMER_UNKNOWN
,
44 /* timeout parameter, to control the polling thread grace period. */
45 int consumer_poll_timeout
= -1;
48 * Flag to inform the polling thread to quit when all fd hung up. Updated by
49 * the consumer_thread_receive_fds when it notices that all fds has hung up.
50 * Also updated by the signal handler (consumer_should_exit()). Read by the
53 volatile int consumer_quit
= 0;
56 * Find a stream. The consumer_data.lock must be locked during this
59 static struct lttng_consumer_stream
*consumer_find_stream(int key
)
61 struct lttng_ht_iter iter
;
62 struct lttng_ht_node_ulong
*node
;
63 struct lttng_consumer_stream
*stream
= NULL
;
65 /* Negative keys are lookup failures */
71 lttng_ht_lookup(consumer_data
.stream_ht
, (void *)((unsigned long) key
),
73 node
= lttng_ht_iter_get_node_ulong(&iter
);
75 stream
= caa_container_of(node
, struct lttng_consumer_stream
, node
);
83 static void consumer_steal_stream_key(int key
)
85 struct lttng_consumer_stream
*stream
;
88 stream
= consumer_find_stream(key
);
92 * We don't want the lookup to match, but we still need
93 * to iterate on this stream when iterating over the hash table. Just
94 * change the node key.
96 stream
->node
.key
= -1;
101 static struct lttng_consumer_channel
*consumer_find_channel(int key
)
103 struct lttng_ht_iter iter
;
104 struct lttng_ht_node_ulong
*node
;
105 struct lttng_consumer_channel
*channel
= NULL
;
107 /* Negative keys are lookup failures */
113 lttng_ht_lookup(consumer_data
.channel_ht
, (void *)((unsigned long) key
),
115 node
= lttng_ht_iter_get_node_ulong(&iter
);
117 channel
= caa_container_of(node
, struct lttng_consumer_channel
, node
);
125 static void consumer_steal_channel_key(int key
)
127 struct lttng_consumer_channel
*channel
;
130 channel
= consumer_find_channel(key
);
134 * We don't want the lookup to match, but we still need
135 * to iterate on this channel when iterating over the hash table. Just
136 * change the node key.
138 channel
->node
.key
= -1;
144 void consumer_free_stream(struct rcu_head
*head
)
146 struct lttng_ht_node_ulong
*node
=
147 caa_container_of(head
, struct lttng_ht_node_ulong
, head
);
148 struct lttng_consumer_stream
*stream
=
149 caa_container_of(node
, struct lttng_consumer_stream
, node
);
155 * Remove a stream from the global list protected by a mutex. This
156 * function is also responsible for freeing its data structures.
158 void consumer_del_stream(struct lttng_consumer_stream
*stream
)
161 struct lttng_ht_iter iter
;
162 struct lttng_consumer_channel
*free_chan
= NULL
;
164 pthread_mutex_lock(&consumer_data
.lock
);
166 switch (consumer_data
.type
) {
167 case LTTNG_CONSUMER_KERNEL
:
168 if (stream
->mmap_base
!= NULL
) {
169 ret
= munmap(stream
->mmap_base
, stream
->mmap_len
);
175 case LTTNG_CONSUMER32_UST
:
176 case LTTNG_CONSUMER64_UST
:
177 lttng_ustconsumer_del_stream(stream
);
180 ERR("Unknown consumer_data type");
186 iter
.iter
.node
= &stream
->node
.node
;
187 ret
= lttng_ht_del(consumer_data
.stream_ht
, &iter
);
192 if (consumer_data
.stream_count
<= 0) {
195 consumer_data
.stream_count
--;
199 if (stream
->out_fd
>= 0) {
200 ret
= close(stream
->out_fd
);
205 if (stream
->wait_fd
>= 0 && !stream
->wait_fd_is_copy
) {
206 ret
= close(stream
->wait_fd
);
211 if (stream
->shm_fd
>= 0 && stream
->wait_fd
!= stream
->shm_fd
) {
212 ret
= close(stream
->shm_fd
);
217 if (!--stream
->chan
->refcount
)
218 free_chan
= stream
->chan
;
220 call_rcu(&stream
->node
.head
, consumer_free_stream
);
222 consumer_data
.need_update
= 1;
223 pthread_mutex_unlock(&consumer_data
.lock
);
226 consumer_del_channel(free_chan
);
229 struct lttng_consumer_stream
*consumer_allocate_stream(
230 int channel_key
, int stream_key
,
231 int shm_fd
, int wait_fd
,
232 enum lttng_consumer_stream_state state
,
234 enum lttng_event_output output
,
235 const char *path_name
,
239 struct lttng_consumer_stream
*stream
;
242 stream
= zmalloc(sizeof(*stream
));
243 if (stream
== NULL
) {
244 perror("malloc struct lttng_consumer_stream");
247 stream
->chan
= consumer_find_channel(channel_key
);
249 perror("Unable to find channel key");
252 stream
->chan
->refcount
++;
253 stream
->key
= stream_key
;
254 stream
->shm_fd
= shm_fd
;
255 stream
->wait_fd
= wait_fd
;
257 stream
->out_fd_offset
= 0;
258 stream
->state
= state
;
259 stream
->mmap_len
= mmap_len
;
260 stream
->mmap_base
= NULL
;
261 stream
->output
= output
;
264 strncpy(stream
->path_name
, path_name
, PATH_MAX
- 1);
265 stream
->path_name
[PATH_MAX
- 1] = '\0';
266 lttng_ht_node_init_ulong(&stream
->node
, stream
->key
);
268 switch (consumer_data
.type
) {
269 case LTTNG_CONSUMER_KERNEL
:
271 case LTTNG_CONSUMER32_UST
:
272 case LTTNG_CONSUMER64_UST
:
273 stream
->cpu
= stream
->chan
->cpucount
++;
274 ret
= lttng_ustconsumer_allocate_stream(stream
);
281 ERR("Unknown consumer_data type");
285 DBG("Allocated stream %s (key %d, shm_fd %d, wait_fd %d, mmap_len %llu, out_fd %d)",
286 stream
->path_name
, stream
->key
,
289 (unsigned long long) stream
->mmap_len
,
296 * Add a stream to the global list protected by a mutex.
298 int consumer_add_stream(struct lttng_consumer_stream
*stream
)
302 pthread_mutex_lock(&consumer_data
.lock
);
303 /* Steal stream identifier, for UST */
304 consumer_steal_stream_key(stream
->key
);
306 lttng_ht_add_unique_ulong(consumer_data
.stream_ht
, &stream
->node
);
308 consumer_data
.stream_count
++;
309 consumer_data
.need_update
= 1;
311 switch (consumer_data
.type
) {
312 case LTTNG_CONSUMER_KERNEL
:
314 case LTTNG_CONSUMER32_UST
:
315 case LTTNG_CONSUMER64_UST
:
316 /* Streams are in CPU number order (we rely on this) */
317 stream
->cpu
= stream
->chan
->nr_streams
++;
320 ERR("Unknown consumer_data type");
326 pthread_mutex_unlock(&consumer_data
.lock
);
332 * Update a stream according to what we just received.
334 void consumer_change_stream_state(int stream_key
,
335 enum lttng_consumer_stream_state state
)
337 struct lttng_consumer_stream
*stream
;
339 pthread_mutex_lock(&consumer_data
.lock
);
340 stream
= consumer_find_stream(stream_key
);
342 stream
->state
= state
;
344 consumer_data
.need_update
= 1;
345 pthread_mutex_unlock(&consumer_data
.lock
);
349 void consumer_free_channel(struct rcu_head
*head
)
351 struct lttng_ht_node_ulong
*node
=
352 caa_container_of(head
, struct lttng_ht_node_ulong
, head
);
353 struct lttng_consumer_channel
*channel
=
354 caa_container_of(node
, struct lttng_consumer_channel
, node
);
360 * Remove a channel from the global list protected by a mutex. This
361 * function is also responsible for freeing its data structures.
363 void consumer_del_channel(struct lttng_consumer_channel
*channel
)
366 struct lttng_ht_iter iter
;
368 pthread_mutex_lock(&consumer_data
.lock
);
370 switch (consumer_data
.type
) {
371 case LTTNG_CONSUMER_KERNEL
:
373 case LTTNG_CONSUMER32_UST
:
374 case LTTNG_CONSUMER64_UST
:
375 lttng_ustconsumer_del_channel(channel
);
378 ERR("Unknown consumer_data type");
384 iter
.iter
.node
= &channel
->node
.node
;
385 ret
= lttng_ht_del(consumer_data
.channel_ht
, &iter
);
389 if (channel
->mmap_base
!= NULL
) {
390 ret
= munmap(channel
->mmap_base
, channel
->mmap_len
);
395 if (channel
->wait_fd
>= 0 && !channel
->wait_fd_is_copy
) {
396 ret
= close(channel
->wait_fd
);
401 if (channel
->shm_fd
>= 0 && channel
->wait_fd
!= channel
->shm_fd
) {
402 ret
= close(channel
->shm_fd
);
408 call_rcu(&channel
->node
.head
, consumer_free_channel
);
410 pthread_mutex_unlock(&consumer_data
.lock
);
413 struct lttng_consumer_channel
*consumer_allocate_channel(
415 int shm_fd
, int wait_fd
,
417 uint64_t max_sb_size
)
419 struct lttng_consumer_channel
*channel
;
422 channel
= zmalloc(sizeof(*channel
));
423 if (channel
== NULL
) {
424 perror("malloc struct lttng_consumer_channel");
427 channel
->key
= channel_key
;
428 channel
->shm_fd
= shm_fd
;
429 channel
->wait_fd
= wait_fd
;
430 channel
->mmap_len
= mmap_len
;
431 channel
->max_sb_size
= max_sb_size
;
432 channel
->refcount
= 0;
433 channel
->nr_streams
= 0;
434 lttng_ht_node_init_ulong(&channel
->node
, channel
->key
);
436 switch (consumer_data
.type
) {
437 case LTTNG_CONSUMER_KERNEL
:
438 channel
->mmap_base
= NULL
;
439 channel
->mmap_len
= 0;
441 case LTTNG_CONSUMER32_UST
:
442 case LTTNG_CONSUMER64_UST
:
443 ret
= lttng_ustconsumer_allocate_channel(channel
);
450 ERR("Unknown consumer_data type");
454 DBG("Allocated channel (key %d, shm_fd %d, wait_fd %d, mmap_len %llu, max_sb_size %llu)",
458 (unsigned long long) channel
->mmap_len
,
459 (unsigned long long) channel
->max_sb_size
);
465 * Add a channel to the global list protected by a mutex.
467 int consumer_add_channel(struct lttng_consumer_channel
*channel
)
469 pthread_mutex_lock(&consumer_data
.lock
);
470 /* Steal channel identifier, for UST */
471 consumer_steal_channel_key(channel
->key
);
473 lttng_ht_add_unique_ulong(consumer_data
.channel_ht
, &channel
->node
);
475 pthread_mutex_unlock(&consumer_data
.lock
);
481 * Allocate the pollfd structure and the local view of the out fds to avoid
482 * doing a lookup in the linked list and concurrency issues when writing is
483 * needed. Called with consumer_data.lock held.
485 * Returns the number of fds in the structures.
487 int consumer_update_poll_array(
488 struct lttng_consumer_local_data
*ctx
, struct pollfd
**pollfd
,
489 struct lttng_consumer_stream
**local_stream
)
492 struct lttng_ht_iter iter
;
493 struct lttng_consumer_stream
*stream
;
495 DBG("Updating poll fd array");
497 cds_lfht_for_each_entry(consumer_data
.stream_ht
->ht
, &iter
.iter
, stream
,
499 if (stream
->state
!= LTTNG_CONSUMER_ACTIVE_STREAM
) {
502 DBG("Active FD %d", stream
->wait_fd
);
503 (*pollfd
)[i
].fd
= stream
->wait_fd
;
504 (*pollfd
)[i
].events
= POLLIN
| POLLPRI
;
505 local_stream
[i
] = stream
;
511 * Insert the consumer_poll_pipe at the end of the array and don't
512 * increment i so nb_fd is the number of real FD.
514 (*pollfd
)[i
].fd
= ctx
->consumer_poll_pipe
[0];
515 (*pollfd
)[i
].events
= POLLIN
;
520 * Poll on the should_quit pipe and the command socket return -1 on error and
521 * should exit, 0 if data is available on the command socket
523 int lttng_consumer_poll_socket(struct pollfd
*consumer_sockpoll
)
528 num_rdy
= poll(consumer_sockpoll
, 2, -1);
531 * Restart interrupted system call.
533 if (errno
== EINTR
) {
536 perror("Poll error");
539 if (consumer_sockpoll
[0].revents
== POLLIN
) {
540 DBG("consumer_should_quit wake up");
550 * Set the error socket.
552 void lttng_consumer_set_error_sock(
553 struct lttng_consumer_local_data
*ctx
, int sock
)
555 ctx
->consumer_error_socket
= sock
;
559 * Set the command socket path.
562 void lttng_consumer_set_command_sock_path(
563 struct lttng_consumer_local_data
*ctx
, char *sock
)
565 ctx
->consumer_command_sock_path
= sock
;
569 * Send return code to the session daemon.
570 * If the socket is not defined, we return 0, it is not a fatal error
572 int lttng_consumer_send_error(
573 struct lttng_consumer_local_data
*ctx
, int cmd
)
575 if (ctx
->consumer_error_socket
> 0) {
576 return lttcomm_send_unix_sock(ctx
->consumer_error_socket
, &cmd
,
577 sizeof(enum lttcomm_sessiond_command
));
584 * Close all the tracefiles and stream fds, should be called when all instances
587 void lttng_consumer_cleanup(void)
589 struct lttng_ht_iter iter
;
590 struct lttng_ht_node_ulong
*node
;
595 * close all outfd. Called when there are no more threads running (after
596 * joining on the threads), no need to protect list iteration with mutex.
598 cds_lfht_for_each_entry(consumer_data
.stream_ht
->ht
, &iter
.iter
, node
,
600 struct lttng_consumer_stream
*stream
=
601 caa_container_of(node
, struct lttng_consumer_stream
, node
);
602 consumer_del_stream(stream
);
605 cds_lfht_for_each_entry(consumer_data
.channel_ht
->ht
, &iter
.iter
, node
,
607 struct lttng_consumer_channel
*channel
=
608 caa_container_of(node
, struct lttng_consumer_channel
, node
);
609 consumer_del_channel(channel
);
616 * Called from signal handler.
618 void lttng_consumer_should_exit(struct lttng_consumer_local_data
*ctx
)
622 ret
= write(ctx
->consumer_should_quit
[1], "4", 1);
624 perror("write consumer quit");
628 void lttng_consumer_sync_trace_file(
629 struct lttng_consumer_stream
*stream
, off_t orig_offset
)
631 int outfd
= stream
->out_fd
;
634 * This does a blocking write-and-wait on any page that belongs to the
635 * subbuffer prior to the one we just wrote.
636 * Don't care about error values, as these are just hints and ways to
637 * limit the amount of page cache used.
639 if (orig_offset
< stream
->chan
->max_sb_size
) {
642 lttng_sync_file_range(outfd
, orig_offset
- stream
->chan
->max_sb_size
,
643 stream
->chan
->max_sb_size
,
644 SYNC_FILE_RANGE_WAIT_BEFORE
645 | SYNC_FILE_RANGE_WRITE
646 | SYNC_FILE_RANGE_WAIT_AFTER
);
648 * Give hints to the kernel about how we access the file:
649 * POSIX_FADV_DONTNEED : we won't re-access data in a near future after
652 * We need to call fadvise again after the file grows because the
653 * kernel does not seem to apply fadvise to non-existing parts of the
656 * Call fadvise _after_ having waited for the page writeback to
657 * complete because the dirty page writeback semantic is not well
658 * defined. So it can be expected to lead to lower throughput in
661 posix_fadvise(outfd
, orig_offset
- stream
->chan
->max_sb_size
,
662 stream
->chan
->max_sb_size
, POSIX_FADV_DONTNEED
);
666 * Initialise the necessary environnement :
667 * - create a new context
668 * - create the poll_pipe
669 * - create the should_quit pipe (for signal handler)
670 * - create the thread pipe (for splice)
672 * Takes a function pointer as argument, this function is called when data is
673 * available on a buffer. This function is responsible to do the
674 * kernctl_get_next_subbuf, read the data with mmap or splice depending on the
675 * buffer configuration and then kernctl_put_next_subbuf at the end.
677 * Returns a pointer to the new context or NULL on error.
679 struct lttng_consumer_local_data
*lttng_consumer_create(
680 enum lttng_consumer_type type
,
681 ssize_t (*buffer_ready
)(struct lttng_consumer_stream
*stream
,
682 struct lttng_consumer_local_data
*ctx
),
683 int (*recv_channel
)(struct lttng_consumer_channel
*channel
),
684 int (*recv_stream
)(struct lttng_consumer_stream
*stream
),
685 int (*update_stream
)(int stream_key
, uint32_t state
))
688 struct lttng_consumer_local_data
*ctx
;
690 assert(consumer_data
.type
== LTTNG_CONSUMER_UNKNOWN
||
691 consumer_data
.type
== type
);
692 consumer_data
.type
= type
;
694 ctx
= zmalloc(sizeof(struct lttng_consumer_local_data
));
696 perror("allocating context");
700 ctx
->consumer_error_socket
= -1;
701 /* assign the callbacks */
702 ctx
->on_buffer_ready
= buffer_ready
;
703 ctx
->on_recv_channel
= recv_channel
;
704 ctx
->on_recv_stream
= recv_stream
;
705 ctx
->on_update_stream
= update_stream
;
707 ret
= pipe(ctx
->consumer_poll_pipe
);
709 perror("Error creating poll pipe");
710 goto error_poll_pipe
;
713 ret
= pipe(ctx
->consumer_should_quit
);
715 perror("Error creating recv pipe");
716 goto error_quit_pipe
;
719 ret
= pipe(ctx
->consumer_thread_pipe
);
721 perror("Error creating thread pipe");
722 goto error_thread_pipe
;
729 for (i
= 0; i
< 2; i
++) {
732 err
= close(ctx
->consumer_should_quit
[i
]);
738 for (i
= 0; i
< 2; i
++) {
741 err
= close(ctx
->consumer_poll_pipe
[i
]);
753 * Close all fds associated with the instance and free the context.
755 void lttng_consumer_destroy(struct lttng_consumer_local_data
*ctx
)
759 ret
= close(ctx
->consumer_error_socket
);
763 ret
= close(ctx
->consumer_thread_pipe
[0]);
767 ret
= close(ctx
->consumer_thread_pipe
[1]);
771 ret
= close(ctx
->consumer_poll_pipe
[0]);
775 ret
= close(ctx
->consumer_poll_pipe
[1]);
779 ret
= close(ctx
->consumer_should_quit
[0]);
783 ret
= close(ctx
->consumer_should_quit
[1]);
787 unlink(ctx
->consumer_command_sock_path
);
792 * Mmap the ring buffer, read it and write the data to the tracefile.
794 * Returns the number of bytes written
796 ssize_t
lttng_consumer_on_read_subbuffer_mmap(
797 struct lttng_consumer_local_data
*ctx
,
798 struct lttng_consumer_stream
*stream
, unsigned long len
)
800 switch (consumer_data
.type
) {
801 case LTTNG_CONSUMER_KERNEL
:
802 return lttng_kconsumer_on_read_subbuffer_mmap(ctx
, stream
, len
);
803 case LTTNG_CONSUMER32_UST
:
804 case LTTNG_CONSUMER64_UST
:
805 return lttng_ustconsumer_on_read_subbuffer_mmap(ctx
, stream
, len
);
807 ERR("Unknown consumer_data type");
815 * Splice the data from the ring buffer to the tracefile.
817 * Returns the number of bytes spliced.
819 ssize_t
lttng_consumer_on_read_subbuffer_splice(
820 struct lttng_consumer_local_data
*ctx
,
821 struct lttng_consumer_stream
*stream
, unsigned long len
)
823 switch (consumer_data
.type
) {
824 case LTTNG_CONSUMER_KERNEL
:
825 return lttng_kconsumer_on_read_subbuffer_splice(ctx
, stream
, len
);
826 case LTTNG_CONSUMER32_UST
:
827 case LTTNG_CONSUMER64_UST
:
830 ERR("Unknown consumer_data type");
838 * Take a snapshot for a specific fd
840 * Returns 0 on success, < 0 on error
842 int lttng_consumer_take_snapshot(struct lttng_consumer_local_data
*ctx
,
843 struct lttng_consumer_stream
*stream
)
845 switch (consumer_data
.type
) {
846 case LTTNG_CONSUMER_KERNEL
:
847 return lttng_kconsumer_take_snapshot(ctx
, stream
);
848 case LTTNG_CONSUMER32_UST
:
849 case LTTNG_CONSUMER64_UST
:
850 return lttng_ustconsumer_take_snapshot(ctx
, stream
);
852 ERR("Unknown consumer_data type");
860 * Get the produced position
862 * Returns 0 on success, < 0 on error
864 int lttng_consumer_get_produced_snapshot(
865 struct lttng_consumer_local_data
*ctx
,
866 struct lttng_consumer_stream
*stream
,
869 switch (consumer_data
.type
) {
870 case LTTNG_CONSUMER_KERNEL
:
871 return lttng_kconsumer_get_produced_snapshot(ctx
, stream
, pos
);
872 case LTTNG_CONSUMER32_UST
:
873 case LTTNG_CONSUMER64_UST
:
874 return lttng_ustconsumer_get_produced_snapshot(ctx
, stream
, pos
);
876 ERR("Unknown consumer_data type");
882 int lttng_consumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
883 int sock
, struct pollfd
*consumer_sockpoll
)
885 switch (consumer_data
.type
) {
886 case LTTNG_CONSUMER_KERNEL
:
887 return lttng_kconsumer_recv_cmd(ctx
, sock
, consumer_sockpoll
);
888 case LTTNG_CONSUMER32_UST
:
889 case LTTNG_CONSUMER64_UST
:
890 return lttng_ustconsumer_recv_cmd(ctx
, sock
, consumer_sockpoll
);
892 ERR("Unknown consumer_data type");
899 * This thread polls the fds in the set to consume the data and write
900 * it to tracefile if necessary.
902 void *lttng_consumer_thread_poll_fds(void *data
)
904 int num_rdy
, num_hup
, high_prio
, ret
, i
;
905 struct pollfd
*pollfd
= NULL
;
906 /* local view of the streams */
907 struct lttng_consumer_stream
**local_stream
= NULL
;
908 /* local view of consumer_data.fds_count */
912 struct lttng_consumer_local_data
*ctx
= data
;
914 rcu_register_thread();
916 local_stream
= zmalloc(sizeof(struct lttng_consumer_stream
));
923 * the fds set has been updated, we need to update our
924 * local array as well
926 pthread_mutex_lock(&consumer_data
.lock
);
927 if (consumer_data
.need_update
) {
928 if (pollfd
!= NULL
) {
932 if (local_stream
!= NULL
) {
937 /* allocate for all fds + 1 for the consumer_poll_pipe */
938 pollfd
= zmalloc((consumer_data
.stream_count
+ 1) * sizeof(struct pollfd
));
939 if (pollfd
== NULL
) {
940 perror("pollfd malloc");
941 pthread_mutex_unlock(&consumer_data
.lock
);
945 /* allocate for all fds + 1 for the consumer_poll_pipe */
946 local_stream
= zmalloc((consumer_data
.stream_count
+ 1) *
947 sizeof(struct lttng_consumer_stream
));
948 if (local_stream
== NULL
) {
949 perror("local_stream malloc");
950 pthread_mutex_unlock(&consumer_data
.lock
);
953 ret
= consumer_update_poll_array(ctx
, &pollfd
, local_stream
);
955 ERR("Error in allocating pollfd or local_outfds");
956 lttng_consumer_send_error(ctx
, CONSUMERD_POLL_ERROR
);
957 pthread_mutex_unlock(&consumer_data
.lock
);
961 consumer_data
.need_update
= 0;
963 pthread_mutex_unlock(&consumer_data
.lock
);
965 /* No FDs and consumer_quit, consumer_cleanup the thread */
966 if (nb_fd
== 0 && consumer_quit
== 1) {
969 /* poll on the array of fds */
971 DBG("polling on %d fd", nb_fd
+ 1);
972 num_rdy
= poll(pollfd
, nb_fd
+ 1, consumer_poll_timeout
);
973 DBG("poll num_rdy : %d", num_rdy
);
976 * Restart interrupted system call.
978 if (errno
== EINTR
) {
981 perror("Poll error");
982 lttng_consumer_send_error(ctx
, CONSUMERD_POLL_ERROR
);
984 } else if (num_rdy
== 0) {
985 DBG("Polling thread timed out");
990 * If the consumer_poll_pipe triggered poll go
991 * directly to the beginning of the loop to update the
992 * array. We want to prioritize array update over
993 * low-priority reads.
995 if (pollfd
[nb_fd
].revents
& POLLIN
) {
996 DBG("consumer_poll_pipe wake up");
997 tmp2
= read(ctx
->consumer_poll_pipe
[0], &tmp
, 1);
999 perror("read consumer poll");
1004 /* Take care of high priority channels first. */
1005 for (i
= 0; i
< nb_fd
; i
++) {
1006 if (pollfd
[i
].revents
& POLLPRI
) {
1009 DBG("Urgent read on fd %d", pollfd
[i
].fd
);
1011 len
= ctx
->on_buffer_ready(local_stream
[i
], ctx
);
1012 /* it's ok to have an unavailable sub-buffer */
1013 if (len
< 0 && len
!= -EAGAIN
) {
1015 } else if (len
> 0) {
1016 local_stream
[i
]->data_read
= 1;
1022 * If we read high prio channel in this loop, try again
1023 * for more high prio data.
1029 /* Take care of low priority channels. */
1030 for (i
= 0; i
< nb_fd
; i
++) {
1031 if ((pollfd
[i
].revents
& POLLIN
) ||
1032 local_stream
[i
]->hangup_flush_done
) {
1035 DBG("Normal read on fd %d", pollfd
[i
].fd
);
1036 len
= ctx
->on_buffer_ready(local_stream
[i
], ctx
);
1037 /* it's ok to have an unavailable sub-buffer */
1038 if (len
< 0 && len
!= -EAGAIN
) {
1040 } else if (len
> 0) {
1041 local_stream
[i
]->data_read
= 1;
1046 /* Handle hangup and errors */
1047 for (i
= 0; i
< nb_fd
; i
++) {
1048 if (!local_stream
[i
]->hangup_flush_done
1049 && (pollfd
[i
].revents
& (POLLHUP
| POLLERR
| POLLNVAL
))
1050 && (consumer_data
.type
== LTTNG_CONSUMER32_UST
1051 || consumer_data
.type
== LTTNG_CONSUMER64_UST
)) {
1052 DBG("fd %d is hup|err|nval. Attempting flush and read.",
1054 lttng_ustconsumer_on_stream_hangup(local_stream
[i
]);
1055 /* Attempt read again, for the data we just flushed. */
1056 local_stream
[i
]->data_read
= 1;
1059 * If the poll flag is HUP/ERR/NVAL and we have
1060 * read no data in this pass, we can remove the
1061 * stream from its hash table.
1063 if ((pollfd
[i
].revents
& POLLHUP
)) {
1064 DBG("Polling fd %d tells it has hung up.", pollfd
[i
].fd
);
1065 if (!local_stream
[i
]->data_read
) {
1066 consumer_del_stream(local_stream
[i
]);
1069 } else if (pollfd
[i
].revents
& POLLERR
) {
1070 ERR("Error returned in polling fd %d.", pollfd
[i
].fd
);
1071 if (!local_stream
[i
]->data_read
) {
1072 consumer_del_stream(local_stream
[i
]);
1075 } else if (pollfd
[i
].revents
& POLLNVAL
) {
1076 ERR("Polling fd %d tells fd is not open.", pollfd
[i
].fd
);
1077 if (!local_stream
[i
]->data_read
) {
1078 consumer_del_stream(local_stream
[i
]);
1082 local_stream
[i
]->data_read
= 0;
1086 DBG("polling thread exiting");
1087 if (pollfd
!= NULL
) {
1091 if (local_stream
!= NULL
) {
1093 local_stream
= NULL
;
1095 rcu_unregister_thread();
1100 * This thread listens on the consumerd socket and receives the file
1101 * descriptors from the session daemon.
1103 void *lttng_consumer_thread_receive_fds(void *data
)
1105 int sock
, client_socket
, ret
;
1107 * structure to poll for incoming data on communication socket avoids
1108 * making blocking sockets.
1110 struct pollfd consumer_sockpoll
[2];
1111 struct lttng_consumer_local_data
*ctx
= data
;
1113 rcu_register_thread();
1115 DBG("Creating command socket %s", ctx
->consumer_command_sock_path
);
1116 unlink(ctx
->consumer_command_sock_path
);
1117 client_socket
= lttcomm_create_unix_sock(ctx
->consumer_command_sock_path
);
1118 if (client_socket
< 0) {
1119 ERR("Cannot create command socket");
1123 ret
= lttcomm_listen_unix_sock(client_socket
);
1128 DBG("Sending ready command to lttng-sessiond");
1129 ret
= lttng_consumer_send_error(ctx
, CONSUMERD_COMMAND_SOCK_READY
);
1130 /* return < 0 on error, but == 0 is not fatal */
1132 ERR("Error sending ready command to lttng-sessiond");
1136 ret
= fcntl(client_socket
, F_SETFL
, O_NONBLOCK
);
1138 perror("fcntl O_NONBLOCK");
1142 /* prepare the FDs to poll : to client socket and the should_quit pipe */
1143 consumer_sockpoll
[0].fd
= ctx
->consumer_should_quit
[0];
1144 consumer_sockpoll
[0].events
= POLLIN
| POLLPRI
;
1145 consumer_sockpoll
[1].fd
= client_socket
;
1146 consumer_sockpoll
[1].events
= POLLIN
| POLLPRI
;
1148 if (lttng_consumer_poll_socket(consumer_sockpoll
) < 0) {
1151 DBG("Connection on client_socket");
1153 /* Blocking call, waiting for transmission */
1154 sock
= lttcomm_accept_unix_sock(client_socket
);
1159 ret
= fcntl(sock
, F_SETFL
, O_NONBLOCK
);
1161 perror("fcntl O_NONBLOCK");
1165 /* update the polling structure to poll on the established socket */
1166 consumer_sockpoll
[1].fd
= sock
;
1167 consumer_sockpoll
[1].events
= POLLIN
| POLLPRI
;
1170 if (lttng_consumer_poll_socket(consumer_sockpoll
) < 0) {
1173 DBG("Incoming command on sock");
1174 ret
= lttng_consumer_recv_cmd(ctx
, sock
, consumer_sockpoll
);
1175 if (ret
== -ENOENT
) {
1176 DBG("Received STOP command");
1180 ERR("Communication interrupted on command socket");
1183 if (consumer_quit
) {
1184 DBG("consumer_thread_receive_fds received quit from signal");
1187 DBG("received fds on sock");
1190 DBG("consumer_thread_receive_fds exiting");
1193 * when all fds have hung up, the polling thread
1199 * 2s of grace period, if no polling events occur during
1200 * this period, the polling thread will exit even if there
1201 * are still open FDs (should not happen, but safety mechanism).
1203 consumer_poll_timeout
= LTTNG_CONSUMER_POLL_TIMEOUT
;
1205 /* wake up the polling thread */
1206 ret
= write(ctx
->consumer_poll_pipe
[1], "4", 1);
1208 perror("poll pipe write");
1210 rcu_unregister_thread();
1214 ssize_t
lttng_consumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
1215 struct lttng_consumer_local_data
*ctx
)
1217 switch (consumer_data
.type
) {
1218 case LTTNG_CONSUMER_KERNEL
:
1219 return lttng_kconsumer_read_subbuffer(stream
, ctx
);
1220 case LTTNG_CONSUMER32_UST
:
1221 case LTTNG_CONSUMER64_UST
:
1222 return lttng_ustconsumer_read_subbuffer(stream
, ctx
);
1224 ERR("Unknown consumer_data type");
1230 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream
*stream
)
1232 switch (consumer_data
.type
) {
1233 case LTTNG_CONSUMER_KERNEL
:
1234 return lttng_kconsumer_on_recv_stream(stream
);
1235 case LTTNG_CONSUMER32_UST
:
1236 case LTTNG_CONSUMER64_UST
:
1237 return lttng_ustconsumer_on_recv_stream(stream
);
1239 ERR("Unknown consumer_data type");
1246 * Allocate and set consumer data hash tables.
1248 void lttng_consumer_init(void)
1250 consumer_data
.stream_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_ULONG
);
1251 consumer_data
.channel_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_ULONG
);