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
6 * modify it under the terms of the GNU General Public License
7 * as published by the Free Software Foundation; only version 2
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.
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.
28 #include <sys/socket.h>
29 #include <sys/types.h>
32 #include <common/common.h>
33 #include <common/kernel-ctl/kernel-ctl.h>
34 #include <common/sessiond-comm/sessiond-comm.h>
35 #include <common/kernel-consumer/kernel-consumer.h>
36 #include <common/ust-consumer/ust-consumer.h>
40 struct lttng_consumer_global_data consumer_data
= {
43 .type
= LTTNG_CONSUMER_UNKNOWN
,
46 /* timeout parameter, to control the polling thread grace period. */
47 int consumer_poll_timeout
= -1;
50 * Flag to inform the polling thread to quit when all fd hung up. Updated by
51 * the consumer_thread_receive_fds when it notices that all fds has hung up.
52 * Also updated by the signal handler (consumer_should_exit()). Read by the
55 volatile int consumer_quit
= 0;
58 * Find a stream. The consumer_data.lock must be locked during this
61 static struct lttng_consumer_stream
*consumer_find_stream(int key
)
63 struct lttng_ht_iter iter
;
64 struct lttng_ht_node_ulong
*node
;
65 struct lttng_consumer_stream
*stream
= NULL
;
67 /* Negative keys are lookup failures */
73 lttng_ht_lookup(consumer_data
.stream_ht
, (void *)((unsigned long) key
),
75 node
= lttng_ht_iter_get_node_ulong(&iter
);
77 stream
= caa_container_of(node
, struct lttng_consumer_stream
, node
);
85 static void consumer_steal_stream_key(int key
)
87 struct lttng_consumer_stream
*stream
;
89 stream
= consumer_find_stream(key
);
94 static struct lttng_consumer_channel
*consumer_find_channel(int key
)
96 struct lttng_ht_iter iter
;
97 struct lttng_ht_node_ulong
*node
;
98 struct lttng_consumer_channel
*channel
= NULL
;
100 /* Negative keys are lookup failures */
106 lttng_ht_lookup(consumer_data
.channel_ht
, (void *)((unsigned long) key
),
108 node
= lttng_ht_iter_get_node_ulong(&iter
);
110 channel
= caa_container_of(node
, struct lttng_consumer_channel
, node
);
118 static void consumer_steal_channel_key(int key
)
120 struct lttng_consumer_channel
*channel
;
122 channel
= consumer_find_channel(key
);
128 void consumer_free_stream(struct rcu_head
*head
)
130 struct lttng_ht_node_ulong
*node
=
131 caa_container_of(head
, struct lttng_ht_node_ulong
, head
);
132 struct lttng_consumer_stream
*stream
=
133 caa_container_of(node
, struct lttng_consumer_stream
, node
);
139 * Remove a stream from the global list protected by a mutex. This
140 * function is also responsible for freeing its data structures.
142 void consumer_del_stream(struct lttng_consumer_stream
*stream
)
145 struct lttng_ht_iter iter
;
146 struct lttng_consumer_channel
*free_chan
= NULL
;
148 pthread_mutex_lock(&consumer_data
.lock
);
150 switch (consumer_data
.type
) {
151 case LTTNG_CONSUMER_KERNEL
:
152 if (stream
->mmap_base
!= NULL
) {
153 ret
= munmap(stream
->mmap_base
, stream
->mmap_len
);
159 case LTTNG_CONSUMER32_UST
:
160 case LTTNG_CONSUMER64_UST
:
161 lttng_ustconsumer_del_stream(stream
);
164 ERR("Unknown consumer_data type");
171 /* Get stream node from hash table */
172 lttng_ht_lookup(consumer_data
.stream_ht
,
173 (void *)((unsigned long) stream
->key
), &iter
);
175 * Remove stream node from hash table. It can fail if it's been
176 * replaced due to key reuse.
178 (void) lttng_ht_del(consumer_data
.stream_ht
, &iter
);
182 if (consumer_data
.stream_count
<= 0) {
185 consumer_data
.stream_count
--;
189 if (stream
->out_fd
>= 0) {
190 ret
= close(stream
->out_fd
);
195 if (stream
->wait_fd
>= 0 && !stream
->wait_fd_is_copy
) {
196 ret
= close(stream
->wait_fd
);
201 if (stream
->shm_fd
>= 0 && stream
->wait_fd
!= stream
->shm_fd
) {
202 ret
= close(stream
->shm_fd
);
207 if (!--stream
->chan
->refcount
)
208 free_chan
= stream
->chan
;
210 call_rcu(&stream
->node
.head
, consumer_free_stream
);
212 consumer_data
.need_update
= 1;
213 pthread_mutex_unlock(&consumer_data
.lock
);
216 consumer_del_channel(free_chan
);
219 struct lttng_consumer_stream
*consumer_allocate_stream(
220 int channel_key
, int stream_key
,
221 int shm_fd
, int wait_fd
,
222 enum lttng_consumer_stream_state state
,
224 enum lttng_event_output output
,
225 const char *path_name
,
229 struct lttng_consumer_stream
*stream
;
232 stream
= zmalloc(sizeof(*stream
));
233 if (stream
== NULL
) {
234 perror("malloc struct lttng_consumer_stream");
237 stream
->chan
= consumer_find_channel(channel_key
);
239 perror("Unable to find channel key");
242 stream
->chan
->refcount
++;
243 stream
->key
= stream_key
;
244 stream
->shm_fd
= shm_fd
;
245 stream
->wait_fd
= wait_fd
;
247 stream
->out_fd_offset
= 0;
248 stream
->state
= state
;
249 stream
->mmap_len
= mmap_len
;
250 stream
->mmap_base
= NULL
;
251 stream
->output
= output
;
254 strncpy(stream
->path_name
, path_name
, PATH_MAX
- 1);
255 stream
->path_name
[PATH_MAX
- 1] = '\0';
256 lttng_ht_node_init_ulong(&stream
->node
, stream
->key
);
258 switch (consumer_data
.type
) {
259 case LTTNG_CONSUMER_KERNEL
:
261 case LTTNG_CONSUMER32_UST
:
262 case LTTNG_CONSUMER64_UST
:
263 stream
->cpu
= stream
->chan
->cpucount
++;
264 ret
= lttng_ustconsumer_allocate_stream(stream
);
271 ERR("Unknown consumer_data type");
275 DBG("Allocated stream %s (key %d, shm_fd %d, wait_fd %d, mmap_len %llu, out_fd %d)",
276 stream
->path_name
, stream
->key
,
279 (unsigned long long) stream
->mmap_len
,
286 * Add a stream to the global list protected by a mutex.
288 int consumer_add_stream(struct lttng_consumer_stream
*stream
)
292 pthread_mutex_lock(&consumer_data
.lock
);
293 /* Steal stream identifier, for UST */
294 consumer_steal_stream_key(stream
->key
);
297 * We simply remove the old channel from the hash table. It's
298 * ok, since we know for sure the sessiond wants to replace it
299 * with the new version, because the key has been reused.
301 (void) lttng_ht_add_replace_ulong(consumer_data
.stream_ht
, &stream
->node
);
303 consumer_data
.stream_count
++;
304 consumer_data
.need_update
= 1;
306 switch (consumer_data
.type
) {
307 case LTTNG_CONSUMER_KERNEL
:
309 case LTTNG_CONSUMER32_UST
:
310 case LTTNG_CONSUMER64_UST
:
311 /* Streams are in CPU number order (we rely on this) */
312 stream
->cpu
= stream
->chan
->nr_streams
++;
315 ERR("Unknown consumer_data type");
321 pthread_mutex_unlock(&consumer_data
.lock
);
327 * Update a stream according to what we just received.
329 void consumer_change_stream_state(int stream_key
,
330 enum lttng_consumer_stream_state state
)
332 struct lttng_consumer_stream
*stream
;
334 pthread_mutex_lock(&consumer_data
.lock
);
335 stream
= consumer_find_stream(stream_key
);
337 stream
->state
= state
;
339 consumer_data
.need_update
= 1;
340 pthread_mutex_unlock(&consumer_data
.lock
);
344 void consumer_free_channel(struct rcu_head
*head
)
346 struct lttng_ht_node_ulong
*node
=
347 caa_container_of(head
, struct lttng_ht_node_ulong
, head
);
348 struct lttng_consumer_channel
*channel
=
349 caa_container_of(node
, struct lttng_consumer_channel
, node
);
355 * Remove a channel from the global list protected by a mutex. This
356 * function is also responsible for freeing its data structures.
358 void consumer_del_channel(struct lttng_consumer_channel
*channel
)
361 struct lttng_ht_iter iter
;
363 pthread_mutex_lock(&consumer_data
.lock
);
365 switch (consumer_data
.type
) {
366 case LTTNG_CONSUMER_KERNEL
:
368 case LTTNG_CONSUMER32_UST
:
369 case LTTNG_CONSUMER64_UST
:
370 lttng_ustconsumer_del_channel(channel
);
373 ERR("Unknown consumer_data type");
380 lttng_ht_lookup(consumer_data
.channel_ht
,
381 (void *)((unsigned long) channel
->key
), &iter
);
384 * Remove channel node from hash table. It can fail if it's been
385 * replaced due to key reuse.
387 (void) lttng_ht_del(consumer_data
.channel_ht
, &iter
);
391 if (channel
->mmap_base
!= NULL
) {
392 ret
= munmap(channel
->mmap_base
, channel
->mmap_len
);
397 if (channel
->wait_fd
>= 0 && !channel
->wait_fd_is_copy
) {
398 ret
= close(channel
->wait_fd
);
403 if (channel
->shm_fd
>= 0 && channel
->wait_fd
!= channel
->shm_fd
) {
404 ret
= close(channel
->shm_fd
);
410 call_rcu(&channel
->node
.head
, consumer_free_channel
);
412 pthread_mutex_unlock(&consumer_data
.lock
);
415 struct lttng_consumer_channel
*consumer_allocate_channel(
417 int shm_fd
, int wait_fd
,
419 uint64_t max_sb_size
)
421 struct lttng_consumer_channel
*channel
;
424 channel
= zmalloc(sizeof(*channel
));
425 if (channel
== NULL
) {
426 perror("malloc struct lttng_consumer_channel");
429 channel
->key
= channel_key
;
430 channel
->shm_fd
= shm_fd
;
431 channel
->wait_fd
= wait_fd
;
432 channel
->mmap_len
= mmap_len
;
433 channel
->max_sb_size
= max_sb_size
;
434 channel
->refcount
= 0;
435 channel
->nr_streams
= 0;
436 lttng_ht_node_init_ulong(&channel
->node
, channel
->key
);
438 switch (consumer_data
.type
) {
439 case LTTNG_CONSUMER_KERNEL
:
440 channel
->mmap_base
= NULL
;
441 channel
->mmap_len
= 0;
443 case LTTNG_CONSUMER32_UST
:
444 case LTTNG_CONSUMER64_UST
:
445 ret
= lttng_ustconsumer_allocate_channel(channel
);
452 ERR("Unknown consumer_data type");
456 DBG("Allocated channel (key %d, shm_fd %d, wait_fd %d, mmap_len %llu, max_sb_size %llu)",
460 (unsigned long long) channel
->mmap_len
,
461 (unsigned long long) channel
->max_sb_size
);
467 * Add a channel to the global list protected by a mutex.
469 int consumer_add_channel(struct lttng_consumer_channel
*channel
)
471 pthread_mutex_lock(&consumer_data
.lock
);
472 /* Steal channel identifier, for UST */
473 consumer_steal_channel_key(channel
->key
);
476 * We simply remove the old channel from the hash table. It's
477 * ok, since we know for sure the sessiond wants to replace it
478 * with the new version, because the key has been reused.
480 (void) lttng_ht_add_replace_ulong(consumer_data
.channel_ht
, &channel
->node
);
482 pthread_mutex_unlock(&consumer_data
.lock
);
488 * Allocate the pollfd structure and the local view of the out fds to avoid
489 * doing a lookup in the linked list and concurrency issues when writing is
490 * needed. Called with consumer_data.lock held.
492 * Returns the number of fds in the structures.
494 int consumer_update_poll_array(
495 struct lttng_consumer_local_data
*ctx
, struct pollfd
**pollfd
,
496 struct lttng_consumer_stream
**local_stream
)
499 struct lttng_ht_iter iter
;
500 struct lttng_consumer_stream
*stream
;
502 DBG("Updating poll fd array");
503 cds_lfht_for_each_entry(consumer_data
.stream_ht
->ht
, &iter
.iter
, stream
,
505 if (stream
->state
!= LTTNG_CONSUMER_ACTIVE_STREAM
) {
508 DBG("Active FD %d", stream
->wait_fd
);
509 (*pollfd
)[i
].fd
= stream
->wait_fd
;
510 (*pollfd
)[i
].events
= POLLIN
| POLLPRI
;
511 local_stream
[i
] = stream
;
516 * Insert the consumer_poll_pipe at the end of the array and don't
517 * increment i so nb_fd is the number of real FD.
519 (*pollfd
)[i
].fd
= ctx
->consumer_poll_pipe
[0];
520 (*pollfd
)[i
].events
= POLLIN
;
525 * Poll on the should_quit pipe and the command socket return -1 on error and
526 * should exit, 0 if data is available on the command socket
528 int lttng_consumer_poll_socket(struct pollfd
*consumer_sockpoll
)
533 num_rdy
= poll(consumer_sockpoll
, 2, -1);
536 * Restart interrupted system call.
538 if (errno
== EINTR
) {
541 perror("Poll error");
544 if (consumer_sockpoll
[0].revents
== POLLIN
) {
545 DBG("consumer_should_quit wake up");
555 * Set the error socket.
557 void lttng_consumer_set_error_sock(
558 struct lttng_consumer_local_data
*ctx
, int sock
)
560 ctx
->consumer_error_socket
= sock
;
564 * Set the command socket path.
567 void lttng_consumer_set_command_sock_path(
568 struct lttng_consumer_local_data
*ctx
, char *sock
)
570 ctx
->consumer_command_sock_path
= sock
;
574 * Send return code to the session daemon.
575 * If the socket is not defined, we return 0, it is not a fatal error
577 int lttng_consumer_send_error(
578 struct lttng_consumer_local_data
*ctx
, int cmd
)
580 if (ctx
->consumer_error_socket
> 0) {
581 return lttcomm_send_unix_sock(ctx
->consumer_error_socket
, &cmd
,
582 sizeof(enum lttcomm_sessiond_command
));
589 * Close all the tracefiles and stream fds, should be called when all instances
592 void lttng_consumer_cleanup(void)
594 struct lttng_ht_iter iter
;
595 struct lttng_ht_node_ulong
*node
;
600 * close all outfd. Called when there are no more threads running (after
601 * joining on the threads), no need to protect list iteration with mutex.
603 cds_lfht_for_each_entry(consumer_data
.stream_ht
->ht
, &iter
.iter
, node
,
605 struct lttng_consumer_stream
*stream
=
606 caa_container_of(node
, struct lttng_consumer_stream
, node
);
607 consumer_del_stream(stream
);
610 cds_lfht_for_each_entry(consumer_data
.channel_ht
->ht
, &iter
.iter
, node
,
612 struct lttng_consumer_channel
*channel
=
613 caa_container_of(node
, struct lttng_consumer_channel
, node
);
614 consumer_del_channel(channel
);
621 * Called from signal handler.
623 void lttng_consumer_should_exit(struct lttng_consumer_local_data
*ctx
)
627 ret
= write(ctx
->consumer_should_quit
[1], "4", 1);
629 perror("write consumer quit");
633 void lttng_consumer_sync_trace_file(
634 struct lttng_consumer_stream
*stream
, off_t orig_offset
)
636 int outfd
= stream
->out_fd
;
639 * This does a blocking write-and-wait on any page that belongs to the
640 * subbuffer prior to the one we just wrote.
641 * Don't care about error values, as these are just hints and ways to
642 * limit the amount of page cache used.
644 if (orig_offset
< stream
->chan
->max_sb_size
) {
647 sync_file_range(outfd
, orig_offset
- stream
->chan
->max_sb_size
,
648 stream
->chan
->max_sb_size
,
649 SYNC_FILE_RANGE_WAIT_BEFORE
650 | SYNC_FILE_RANGE_WRITE
651 | SYNC_FILE_RANGE_WAIT_AFTER
);
653 * Give hints to the kernel about how we access the file:
654 * POSIX_FADV_DONTNEED : we won't re-access data in a near future after
657 * We need to call fadvise again after the file grows because the
658 * kernel does not seem to apply fadvise to non-existing parts of the
661 * Call fadvise _after_ having waited for the page writeback to
662 * complete because the dirty page writeback semantic is not well
663 * defined. So it can be expected to lead to lower throughput in
666 posix_fadvise(outfd
, orig_offset
- stream
->chan
->max_sb_size
,
667 stream
->chan
->max_sb_size
, POSIX_FADV_DONTNEED
);
671 * Initialise the necessary environnement :
672 * - create a new context
673 * - create the poll_pipe
674 * - create the should_quit pipe (for signal handler)
675 * - create the thread pipe (for splice)
677 * Takes a function pointer as argument, this function is called when data is
678 * available on a buffer. This function is responsible to do the
679 * kernctl_get_next_subbuf, read the data with mmap or splice depending on the
680 * buffer configuration and then kernctl_put_next_subbuf at the end.
682 * Returns a pointer to the new context or NULL on error.
684 struct lttng_consumer_local_data
*lttng_consumer_create(
685 enum lttng_consumer_type type
,
686 ssize_t (*buffer_ready
)(struct lttng_consumer_stream
*stream
,
687 struct lttng_consumer_local_data
*ctx
),
688 int (*recv_channel
)(struct lttng_consumer_channel
*channel
),
689 int (*recv_stream
)(struct lttng_consumer_stream
*stream
),
690 int (*update_stream
)(int stream_key
, uint32_t state
))
693 struct lttng_consumer_local_data
*ctx
;
695 assert(consumer_data
.type
== LTTNG_CONSUMER_UNKNOWN
||
696 consumer_data
.type
== type
);
697 consumer_data
.type
= type
;
699 ctx
= zmalloc(sizeof(struct lttng_consumer_local_data
));
701 perror("allocating context");
705 ctx
->consumer_error_socket
= -1;
706 /* assign the callbacks */
707 ctx
->on_buffer_ready
= buffer_ready
;
708 ctx
->on_recv_channel
= recv_channel
;
709 ctx
->on_recv_stream
= recv_stream
;
710 ctx
->on_update_stream
= update_stream
;
712 ret
= pipe(ctx
->consumer_poll_pipe
);
714 perror("Error creating poll pipe");
715 goto error_poll_pipe
;
718 ret
= pipe(ctx
->consumer_should_quit
);
720 perror("Error creating recv pipe");
721 goto error_quit_pipe
;
724 ret
= pipe(ctx
->consumer_thread_pipe
);
726 perror("Error creating thread pipe");
727 goto error_thread_pipe
;
734 for (i
= 0; i
< 2; i
++) {
737 err
= close(ctx
->consumer_should_quit
[i
]);
743 for (i
= 0; i
< 2; i
++) {
746 err
= close(ctx
->consumer_poll_pipe
[i
]);
758 * Close all fds associated with the instance and free the context.
760 void lttng_consumer_destroy(struct lttng_consumer_local_data
*ctx
)
764 ret
= close(ctx
->consumer_error_socket
);
768 ret
= close(ctx
->consumer_thread_pipe
[0]);
772 ret
= close(ctx
->consumer_thread_pipe
[1]);
776 ret
= close(ctx
->consumer_poll_pipe
[0]);
780 ret
= close(ctx
->consumer_poll_pipe
[1]);
784 ret
= close(ctx
->consumer_should_quit
[0]);
788 ret
= close(ctx
->consumer_should_quit
[1]);
792 unlink(ctx
->consumer_command_sock_path
);
797 * Mmap the ring buffer, read it and write the data to the tracefile.
799 * Returns the number of bytes written
801 ssize_t
lttng_consumer_on_read_subbuffer_mmap(
802 struct lttng_consumer_local_data
*ctx
,
803 struct lttng_consumer_stream
*stream
, unsigned long len
)
805 switch (consumer_data
.type
) {
806 case LTTNG_CONSUMER_KERNEL
:
807 return lttng_kconsumer_on_read_subbuffer_mmap(ctx
, stream
, len
);
808 case LTTNG_CONSUMER32_UST
:
809 case LTTNG_CONSUMER64_UST
:
810 return lttng_ustconsumer_on_read_subbuffer_mmap(ctx
, stream
, len
);
812 ERR("Unknown consumer_data type");
818 * Splice the data from the ring buffer to the tracefile.
820 * Returns the number of bytes spliced.
822 ssize_t
lttng_consumer_on_read_subbuffer_splice(
823 struct lttng_consumer_local_data
*ctx
,
824 struct lttng_consumer_stream
*stream
, unsigned long len
)
826 switch (consumer_data
.type
) {
827 case LTTNG_CONSUMER_KERNEL
:
828 return lttng_kconsumer_on_read_subbuffer_splice(ctx
, stream
, len
);
829 case LTTNG_CONSUMER32_UST
:
830 case LTTNG_CONSUMER64_UST
:
833 ERR("Unknown consumer_data type");
841 * Take a snapshot for a specific fd
843 * Returns 0 on success, < 0 on error
845 int lttng_consumer_take_snapshot(struct lttng_consumer_local_data
*ctx
,
846 struct lttng_consumer_stream
*stream
)
848 switch (consumer_data
.type
) {
849 case LTTNG_CONSUMER_KERNEL
:
850 return lttng_kconsumer_take_snapshot(ctx
, stream
);
851 case LTTNG_CONSUMER32_UST
:
852 case LTTNG_CONSUMER64_UST
:
853 return lttng_ustconsumer_take_snapshot(ctx
, stream
);
855 ERR("Unknown consumer_data type");
863 * Get the produced position
865 * Returns 0 on success, < 0 on error
867 int lttng_consumer_get_produced_snapshot(
868 struct lttng_consumer_local_data
*ctx
,
869 struct lttng_consumer_stream
*stream
,
872 switch (consumer_data
.type
) {
873 case LTTNG_CONSUMER_KERNEL
:
874 return lttng_kconsumer_get_produced_snapshot(ctx
, stream
, pos
);
875 case LTTNG_CONSUMER32_UST
:
876 case LTTNG_CONSUMER64_UST
:
877 return lttng_ustconsumer_get_produced_snapshot(ctx
, stream
, pos
);
879 ERR("Unknown consumer_data type");
885 int lttng_consumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
886 int sock
, struct pollfd
*consumer_sockpoll
)
888 switch (consumer_data
.type
) {
889 case LTTNG_CONSUMER_KERNEL
:
890 return lttng_kconsumer_recv_cmd(ctx
, sock
, consumer_sockpoll
);
891 case LTTNG_CONSUMER32_UST
:
892 case LTTNG_CONSUMER64_UST
:
893 return lttng_ustconsumer_recv_cmd(ctx
, sock
, consumer_sockpoll
);
895 ERR("Unknown consumer_data type");
902 * This thread polls the fds in the set to consume the data and write
903 * it to tracefile if necessary.
905 void *lttng_consumer_thread_poll_fds(void *data
)
907 int num_rdy
, num_hup
, high_prio
, ret
, i
;
908 struct pollfd
*pollfd
= NULL
;
909 /* local view of the streams */
910 struct lttng_consumer_stream
**local_stream
= NULL
;
911 /* local view of consumer_data.fds_count */
915 struct lttng_consumer_local_data
*ctx
= data
;
917 rcu_register_thread();
919 local_stream
= zmalloc(sizeof(struct lttng_consumer_stream
));
926 * the fds set has been updated, we need to update our
927 * local array as well
929 pthread_mutex_lock(&consumer_data
.lock
);
930 if (consumer_data
.need_update
) {
931 if (pollfd
!= NULL
) {
935 if (local_stream
!= NULL
) {
940 /* allocate for all fds + 1 for the consumer_poll_pipe */
941 pollfd
= zmalloc((consumer_data
.stream_count
+ 1) * sizeof(struct pollfd
));
942 if (pollfd
== NULL
) {
943 perror("pollfd malloc");
944 pthread_mutex_unlock(&consumer_data
.lock
);
948 /* allocate for all fds + 1 for the consumer_poll_pipe */
949 local_stream
= zmalloc((consumer_data
.stream_count
+ 1) *
950 sizeof(struct lttng_consumer_stream
));
951 if (local_stream
== NULL
) {
952 perror("local_stream malloc");
953 pthread_mutex_unlock(&consumer_data
.lock
);
956 ret
= consumer_update_poll_array(ctx
, &pollfd
, local_stream
);
958 ERR("Error in allocating pollfd or local_outfds");
959 lttng_consumer_send_error(ctx
, CONSUMERD_POLL_ERROR
);
960 pthread_mutex_unlock(&consumer_data
.lock
);
964 consumer_data
.need_update
= 0;
966 pthread_mutex_unlock(&consumer_data
.lock
);
968 /* No FDs and consumer_quit, consumer_cleanup the thread */
969 if (nb_fd
== 0 && consumer_quit
== 1) {
972 /* poll on the array of fds */
974 DBG("polling on %d fd", nb_fd
+ 1);
975 num_rdy
= poll(pollfd
, nb_fd
+ 1, consumer_poll_timeout
);
976 DBG("poll num_rdy : %d", num_rdy
);
979 * Restart interrupted system call.
981 if (errno
== EINTR
) {
984 perror("Poll error");
985 lttng_consumer_send_error(ctx
, CONSUMERD_POLL_ERROR
);
987 } else if (num_rdy
== 0) {
988 DBG("Polling thread timed out");
993 * If the consumer_poll_pipe triggered poll go
994 * directly to the beginning of the loop to update the
995 * array. We want to prioritize array update over
996 * low-priority reads.
998 if (pollfd
[nb_fd
].revents
& POLLIN
) {
999 DBG("consumer_poll_pipe wake up");
1000 tmp2
= read(ctx
->consumer_poll_pipe
[0], &tmp
, 1);
1002 perror("read consumer poll");
1007 /* Take care of high priority channels first. */
1008 for (i
= 0; i
< nb_fd
; i
++) {
1009 if (pollfd
[i
].revents
& POLLPRI
) {
1012 DBG("Urgent read on fd %d", pollfd
[i
].fd
);
1014 len
= ctx
->on_buffer_ready(local_stream
[i
], ctx
);
1015 /* it's ok to have an unavailable sub-buffer */
1016 if (len
< 0 && len
!= -EAGAIN
) {
1018 } else if (len
> 0) {
1019 local_stream
[i
]->data_read
= 1;
1025 * If we read high prio channel in this loop, try again
1026 * for more high prio data.
1032 /* Take care of low priority channels. */
1033 for (i
= 0; i
< nb_fd
; i
++) {
1034 if ((pollfd
[i
].revents
& POLLIN
) ||
1035 local_stream
[i
]->hangup_flush_done
) {
1038 assert(!(pollfd
[i
].revents
& POLLERR
));
1039 assert(!(pollfd
[i
].revents
& POLLNVAL
));
1040 DBG("Normal read on fd %d", pollfd
[i
].fd
);
1041 len
= ctx
->on_buffer_ready(local_stream
[i
], ctx
);
1042 /* it's ok to have an unavailable sub-buffer */
1043 if (len
< 0 && len
!= -EAGAIN
) {
1045 } else if (len
> 0) {
1046 local_stream
[i
]->data_read
= 1;
1051 /* Handle hangup and errors */
1052 for (i
= 0; i
< nb_fd
; i
++) {
1053 if (!local_stream
[i
]->hangup_flush_done
1054 && (pollfd
[i
].revents
& (POLLHUP
| POLLERR
| POLLNVAL
))
1055 && (consumer_data
.type
== LTTNG_CONSUMER32_UST
1056 || consumer_data
.type
== LTTNG_CONSUMER64_UST
)) {
1057 DBG("fd %d is hup|err|nval. Attempting flush and read.",
1059 lttng_ustconsumer_on_stream_hangup(local_stream
[i
]);
1060 /* Attempt read again, for the data we just flushed. */
1061 local_stream
[i
]->data_read
= 1;
1064 * If the poll flag is HUP/ERR/NVAL and we have
1065 * read no data in this pass, we can remove the
1066 * stream from its hash table.
1068 if ((pollfd
[i
].revents
& POLLHUP
)) {
1069 DBG("Polling fd %d tells it has hung up.", pollfd
[i
].fd
);
1070 if (!local_stream
[i
]->data_read
) {
1071 consumer_del_stream(local_stream
[i
]);
1074 } else if (pollfd
[i
].revents
& POLLERR
) {
1075 ERR("Error returned in polling fd %d.", pollfd
[i
].fd
);
1076 if (!local_stream
[i
]->data_read
) {
1077 consumer_del_stream(local_stream
[i
]);
1080 } else if (pollfd
[i
].revents
& POLLNVAL
) {
1081 ERR("Polling fd %d tells fd is not open.", pollfd
[i
].fd
);
1082 if (!local_stream
[i
]->data_read
) {
1083 consumer_del_stream(local_stream
[i
]);
1087 local_stream
[i
]->data_read
= 0;
1091 DBG("polling thread exiting");
1092 if (pollfd
!= NULL
) {
1096 if (local_stream
!= NULL
) {
1098 local_stream
= NULL
;
1100 rcu_unregister_thread();
1105 * This thread listens on the consumerd socket and receives the file
1106 * descriptors from the session daemon.
1108 void *lttng_consumer_thread_receive_fds(void *data
)
1110 int sock
, client_socket
, ret
;
1112 * structure to poll for incoming data on communication socket avoids
1113 * making blocking sockets.
1115 struct pollfd consumer_sockpoll
[2];
1116 struct lttng_consumer_local_data
*ctx
= data
;
1118 rcu_register_thread();
1120 DBG("Creating command socket %s", ctx
->consumer_command_sock_path
);
1121 unlink(ctx
->consumer_command_sock_path
);
1122 client_socket
= lttcomm_create_unix_sock(ctx
->consumer_command_sock_path
);
1123 if (client_socket
< 0) {
1124 ERR("Cannot create command socket");
1128 ret
= lttcomm_listen_unix_sock(client_socket
);
1133 DBG("Sending ready command to lttng-sessiond");
1134 ret
= lttng_consumer_send_error(ctx
, CONSUMERD_COMMAND_SOCK_READY
);
1135 /* return < 0 on error, but == 0 is not fatal */
1137 ERR("Error sending ready command to lttng-sessiond");
1141 ret
= fcntl(client_socket
, F_SETFL
, O_NONBLOCK
);
1143 perror("fcntl O_NONBLOCK");
1147 /* prepare the FDs to poll : to client socket and the should_quit pipe */
1148 consumer_sockpoll
[0].fd
= ctx
->consumer_should_quit
[0];
1149 consumer_sockpoll
[0].events
= POLLIN
| POLLPRI
;
1150 consumer_sockpoll
[1].fd
= client_socket
;
1151 consumer_sockpoll
[1].events
= POLLIN
| POLLPRI
;
1153 if (lttng_consumer_poll_socket(consumer_sockpoll
) < 0) {
1156 DBG("Connection on client_socket");
1158 /* Blocking call, waiting for transmission */
1159 sock
= lttcomm_accept_unix_sock(client_socket
);
1164 ret
= fcntl(sock
, F_SETFL
, O_NONBLOCK
);
1166 perror("fcntl O_NONBLOCK");
1170 /* update the polling structure to poll on the established socket */
1171 consumer_sockpoll
[1].fd
= sock
;
1172 consumer_sockpoll
[1].events
= POLLIN
| POLLPRI
;
1175 if (lttng_consumer_poll_socket(consumer_sockpoll
) < 0) {
1178 DBG("Incoming command on sock");
1179 ret
= lttng_consumer_recv_cmd(ctx
, sock
, consumer_sockpoll
);
1180 if (ret
== -ENOENT
) {
1181 DBG("Received STOP command");
1185 ERR("Communication interrupted on command socket");
1188 if (consumer_quit
) {
1189 DBG("consumer_thread_receive_fds received quit from signal");
1192 DBG("received fds on sock");
1195 DBG("consumer_thread_receive_fds exiting");
1198 * when all fds have hung up, the polling thread
1204 * 2s of grace period, if no polling events occur during
1205 * this period, the polling thread will exit even if there
1206 * are still open FDs (should not happen, but safety mechanism).
1208 consumer_poll_timeout
= LTTNG_CONSUMER_POLL_TIMEOUT
;
1210 /* wake up the polling thread */
1211 ret
= write(ctx
->consumer_poll_pipe
[1], "4", 1);
1213 perror("poll pipe write");
1215 rcu_unregister_thread();
1219 ssize_t
lttng_consumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
1220 struct lttng_consumer_local_data
*ctx
)
1222 switch (consumer_data
.type
) {
1223 case LTTNG_CONSUMER_KERNEL
:
1224 return lttng_kconsumer_read_subbuffer(stream
, ctx
);
1225 case LTTNG_CONSUMER32_UST
:
1226 case LTTNG_CONSUMER64_UST
:
1227 return lttng_ustconsumer_read_subbuffer(stream
, ctx
);
1229 ERR("Unknown consumer_data type");
1235 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream
*stream
)
1237 switch (consumer_data
.type
) {
1238 case LTTNG_CONSUMER_KERNEL
:
1239 return lttng_kconsumer_on_recv_stream(stream
);
1240 case LTTNG_CONSUMER32_UST
:
1241 case LTTNG_CONSUMER64_UST
:
1242 return lttng_ustconsumer_on_recv_stream(stream
);
1244 ERR("Unknown consumer_data type");
1251 * Allocate and set consumer data hash tables.
1253 void lttng_consumer_init(void)
1255 consumer_data
.stream_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_ULONG
);
1256 consumer_data
.channel_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_ULONG
);