2 * Copyright (C) 2012 - Julien Desfossez <julien.desfossez@efficios.com>
3 * David Goulet <dgoulet@efficios.com>
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License, version 2 only, as
7 * 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 with
15 * this program; if not, write to the Free Software Foundation, Inc., 51
16 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
24 #include <bin/lttng-consumerd/health-consumerd.h>
25 #include <common/common.h>
26 #include <common/compat/endian.h>
27 #include <common/kernel-ctl/kernel-ctl.h>
28 #include <common/kernel-consumer/kernel-consumer.h>
29 #include <common/consumer-stream.h>
31 #include "consumer-timer.h"
32 #include "consumer-testpoint.h"
33 #include "ust-consumer/ust-consumer.h"
35 static struct timer_signal_data timer_signal
= {
39 .lock
= PTHREAD_MUTEX_INITIALIZER
,
43 * Set custom signal mask to current thread.
45 static void setmask(sigset_t
*mask
)
49 ret
= sigemptyset(mask
);
51 PERROR("sigemptyset");
53 ret
= sigaddset(mask
, LTTNG_CONSUMER_SIG_SWITCH
);
55 PERROR("sigaddset switch");
57 ret
= sigaddset(mask
, LTTNG_CONSUMER_SIG_TEARDOWN
);
59 PERROR("sigaddset teardown");
61 ret
= sigaddset(mask
, LTTNG_CONSUMER_SIG_LIVE
);
63 PERROR("sigaddset live");
68 * Execute action on a timer switch.
70 * Beware: metadata_switch_timer() should *never* take a mutex also held
71 * while consumer_timer_switch_stop() is called. It would result in
74 static void metadata_switch_timer(struct lttng_consumer_local_data
*ctx
,
75 int sig
, siginfo_t
*si
, void *uc
)
78 struct lttng_consumer_channel
*channel
;
80 channel
= si
->si_value
.sival_ptr
;
83 if (channel
->switch_timer_error
) {
87 DBG("Switch timer for channel %" PRIu64
, channel
->key
);
89 case LTTNG_CONSUMER32_UST
:
90 case LTTNG_CONSUMER64_UST
:
92 * Locks taken by lttng_ustconsumer_request_metadata():
93 * - metadata_socket_lock
94 * - Calling lttng_ustconsumer_recv_metadata():
95 * - channel->metadata_cache->lock
96 * - Calling consumer_metadata_cache_flushed():
97 * - channel->timer_lock
98 * - channel->metadata_cache->lock
100 * Ensure that neither consumer_data.lock nor
101 * channel->lock are taken within this function, since
102 * they are held while consumer_timer_switch_stop() is
105 ret
= lttng_ustconsumer_request_metadata(ctx
, channel
, 1, 1);
107 channel
->switch_timer_error
= 1;
110 case LTTNG_CONSUMER_KERNEL
:
111 case LTTNG_CONSUMER_UNKNOWN
:
117 static int send_empty_index(struct lttng_consumer_stream
*stream
, uint64_t ts
,
121 struct ctf_packet_index index
;
123 memset(&index
, 0, sizeof(index
));
124 index
.stream_id
= htobe64(stream_id
);
125 index
.timestamp_end
= htobe64(ts
);
126 ret
= consumer_stream_write_index(stream
, &index
);
135 int consumer_flush_kernel_index(struct lttng_consumer_stream
*stream
)
137 uint64_t ts
, stream_id
;
140 ret
= kernctl_get_current_timestamp(stream
->wait_fd
, &ts
);
142 ERR("Failed to get the current timestamp");
145 ret
= kernctl_buffer_flush(stream
->wait_fd
);
147 ERR("Failed to flush kernel stream");
150 ret
= kernctl_snapshot(stream
->wait_fd
);
152 if (errno
!= EAGAIN
&& errno
!= ENODATA
) {
153 PERROR("live timer kernel snapshot");
157 ret
= kernctl_get_stream_id(stream
->wait_fd
, &stream_id
);
159 PERROR("kernctl_get_stream_id");
162 DBG("Stream %" PRIu64
" empty, sending beacon", stream
->key
);
163 ret
= send_empty_index(stream
, ts
, stream_id
);
173 static int check_kernel_stream(struct lttng_consumer_stream
*stream
)
178 * While holding the stream mutex, try to take a snapshot, if it
179 * succeeds, it means that data is ready to be sent, just let the data
180 * thread handle that. Otherwise, if the snapshot returns EAGAIN, it
181 * means that there is no data to read after the flush, so we can
182 * safely send the empty index.
184 * Doing a trylock and checking if waiting on metadata if
185 * trylock fails. Bail out of the stream is indeed waiting for
186 * metadata to be pushed. Busy wait on trylock otherwise.
189 ret
= pthread_mutex_trylock(&stream
->lock
);
192 break; /* We have the lock. */
194 pthread_mutex_lock(&stream
->metadata_timer_lock
);
195 if (stream
->waiting_on_metadata
) {
197 stream
->missed_metadata_flush
= true;
198 pthread_mutex_unlock(&stream
->metadata_timer_lock
);
199 goto end
; /* Bail out. */
201 pthread_mutex_unlock(&stream
->metadata_timer_lock
);
206 ERR("Unexpected pthread_mutex_trylock error %d", ret
);
212 ret
= consumer_flush_kernel_index(stream
);
213 pthread_mutex_unlock(&stream
->lock
);
218 int consumer_flush_ust_index(struct lttng_consumer_stream
*stream
)
220 uint64_t ts
, stream_id
;
223 ret
= cds_lfht_is_node_deleted(&stream
->node
.node
);
228 ret
= lttng_ustconsumer_get_current_timestamp(stream
, &ts
);
230 ERR("Failed to get the current timestamp");
233 lttng_ustconsumer_flush_buffer(stream
, 1);
234 ret
= lttng_ustconsumer_take_snapshot(stream
);
236 if (ret
!= -EAGAIN
) {
237 ERR("Taking UST snapshot");
241 ret
= lttng_ustconsumer_get_stream_id(stream
, &stream_id
);
243 PERROR("ustctl_get_stream_id");
246 DBG("Stream %" PRIu64
" empty, sending beacon", stream
->key
);
247 ret
= send_empty_index(stream
, ts
, stream_id
);
257 static int check_ust_stream(struct lttng_consumer_stream
*stream
)
262 assert(stream
->ustream
);
264 * While holding the stream mutex, try to take a snapshot, if it
265 * succeeds, it means that data is ready to be sent, just let the data
266 * thread handle that. Otherwise, if the snapshot returns EAGAIN, it
267 * means that there is no data to read after the flush, so we can
268 * safely send the empty index.
270 * Doing a trylock and checking if waiting on metadata if
271 * trylock fails. Bail out of the stream is indeed waiting for
272 * metadata to be pushed. Busy wait on trylock otherwise.
275 ret
= pthread_mutex_trylock(&stream
->lock
);
278 break; /* We have the lock. */
280 pthread_mutex_lock(&stream
->metadata_timer_lock
);
281 if (stream
->waiting_on_metadata
) {
283 stream
->missed_metadata_flush
= true;
284 pthread_mutex_unlock(&stream
->metadata_timer_lock
);
285 goto end
; /* Bail out. */
287 pthread_mutex_unlock(&stream
->metadata_timer_lock
);
292 ERR("Unexpected pthread_mutex_trylock error %d", ret
);
298 ret
= consumer_flush_ust_index(stream
);
299 pthread_mutex_unlock(&stream
->lock
);
305 * Execute action on a live timer
307 static void live_timer(struct lttng_consumer_local_data
*ctx
,
308 int sig
, siginfo_t
*si
, void *uc
)
311 struct lttng_consumer_channel
*channel
;
312 struct lttng_consumer_stream
*stream
;
314 struct lttng_ht_iter iter
;
316 channel
= si
->si_value
.sival_ptr
;
319 if (channel
->switch_timer_error
) {
322 ht
= consumer_data
.stream_per_chan_id_ht
;
324 DBG("Live timer for channel %" PRIu64
, channel
->key
);
328 case LTTNG_CONSUMER32_UST
:
329 case LTTNG_CONSUMER64_UST
:
330 cds_lfht_for_each_entry_duplicate(ht
->ht
,
331 ht
->hash_fct(&channel
->key
, lttng_ht_seed
),
332 ht
->match_fct
, &channel
->key
, &iter
.iter
,
333 stream
, node_channel_id
.node
) {
334 ret
= check_ust_stream(stream
);
340 case LTTNG_CONSUMER_KERNEL
:
341 cds_lfht_for_each_entry_duplicate(ht
->ht
,
342 ht
->hash_fct(&channel
->key
, lttng_ht_seed
),
343 ht
->match_fct
, &channel
->key
, &iter
.iter
,
344 stream
, node_channel_id
.node
) {
345 ret
= check_kernel_stream(stream
);
351 case LTTNG_CONSUMER_UNKNOWN
:
364 void consumer_timer_signal_thread_qs(unsigned int signr
)
366 sigset_t pending_set
;
370 * We need to be the only thread interacting with the thread
371 * that manages signals for teardown synchronization.
373 pthread_mutex_lock(&timer_signal
.lock
);
375 /* Ensure we don't have any signal queued for this channel. */
377 ret
= sigemptyset(&pending_set
);
379 PERROR("sigemptyset");
381 ret
= sigpending(&pending_set
);
383 PERROR("sigpending");
385 if (!sigismember(&pending_set
, LTTNG_CONSUMER_SIG_SWITCH
)) {
392 * From this point, no new signal handler will be fired that would try to
393 * access "chan". However, we still need to wait for any currently
394 * executing handler to complete.
397 CMM_STORE_SHARED(timer_signal
.qs_done
, 0);
401 * Kill with LTTNG_CONSUMER_SIG_TEARDOWN, so signal management thread wakes
404 kill(getpid(), LTTNG_CONSUMER_SIG_TEARDOWN
);
406 while (!CMM_LOAD_SHARED(timer_signal
.qs_done
)) {
411 pthread_mutex_unlock(&timer_signal
.lock
);
415 * Set the timer for periodical metadata flush.
417 void consumer_timer_switch_start(struct lttng_consumer_channel
*channel
,
418 unsigned int switch_timer_interval
)
422 struct itimerspec its
;
425 assert(channel
->key
);
427 if (switch_timer_interval
== 0) {
431 sev
.sigev_notify
= SIGEV_SIGNAL
;
432 sev
.sigev_signo
= LTTNG_CONSUMER_SIG_SWITCH
;
433 sev
.sigev_value
.sival_ptr
= channel
;
434 ret
= timer_create(CLOCKID
, &sev
, &channel
->switch_timer
);
436 PERROR("timer_create");
438 channel
->switch_timer_enabled
= 1;
440 its
.it_value
.tv_sec
= switch_timer_interval
/ 1000000;
441 its
.it_value
.tv_nsec
= switch_timer_interval
% 1000000;
442 its
.it_interval
.tv_sec
= its
.it_value
.tv_sec
;
443 its
.it_interval
.tv_nsec
= its
.it_value
.tv_nsec
;
445 ret
= timer_settime(channel
->switch_timer
, 0, &its
, NULL
);
447 PERROR("timer_settime");
452 * Stop and delete timer.
454 void consumer_timer_switch_stop(struct lttng_consumer_channel
*channel
)
460 ret
= timer_delete(channel
->switch_timer
);
462 PERROR("timer_delete");
465 consumer_timer_signal_thread_qs(LTTNG_CONSUMER_SIG_SWITCH
);
467 channel
->switch_timer
= 0;
468 channel
->switch_timer_enabled
= 0;
472 * Set the timer for the live mode.
474 void consumer_timer_live_start(struct lttng_consumer_channel
*channel
,
475 int live_timer_interval
)
479 struct itimerspec its
;
482 assert(channel
->key
);
484 if (live_timer_interval
<= 0) {
488 sev
.sigev_notify
= SIGEV_SIGNAL
;
489 sev
.sigev_signo
= LTTNG_CONSUMER_SIG_LIVE
;
490 sev
.sigev_value
.sival_ptr
= channel
;
491 ret
= timer_create(CLOCKID
, &sev
, &channel
->live_timer
);
493 PERROR("timer_create");
495 channel
->live_timer_enabled
= 1;
497 its
.it_value
.tv_sec
= live_timer_interval
/ 1000000;
498 its
.it_value
.tv_nsec
= live_timer_interval
% 1000000;
499 its
.it_interval
.tv_sec
= its
.it_value
.tv_sec
;
500 its
.it_interval
.tv_nsec
= its
.it_value
.tv_nsec
;
502 ret
= timer_settime(channel
->live_timer
, 0, &its
, NULL
);
504 PERROR("timer_settime");
509 * Stop and delete timer.
511 void consumer_timer_live_stop(struct lttng_consumer_channel
*channel
)
517 ret
= timer_delete(channel
->live_timer
);
519 PERROR("timer_delete");
522 consumer_timer_signal_thread_qs(LTTNG_CONSUMER_SIG_LIVE
);
524 channel
->live_timer
= 0;
525 channel
->live_timer_enabled
= 0;
529 * Block the RT signals for the entire process. It must be called from the
530 * consumer main before creating the threads
532 int consumer_signal_init(void)
537 /* Block signal for entire process, so only our thread processes it. */
539 ret
= pthread_sigmask(SIG_BLOCK
, &mask
, NULL
);
542 PERROR("pthread_sigmask");
549 * This thread is the sighandler for signals LTTNG_CONSUMER_SIG_SWITCH,
550 * LTTNG_CONSUMER_SIG_TEARDOWN and LTTNG_CONSUMER_SIG_LIVE.
552 void *consumer_timer_thread(void *data
)
557 struct lttng_consumer_local_data
*ctx
= data
;
559 rcu_register_thread();
561 health_register(health_consumerd
, HEALTH_CONSUMERD_TYPE_METADATA_TIMER
);
563 if (testpoint(consumerd_thread_metadata_timer
)) {
564 goto error_testpoint
;
567 health_code_update();
569 /* Only self thread will receive signal mask. */
571 CMM_STORE_SHARED(timer_signal
.tid
, pthread_self());
574 health_code_update();
577 signr
= sigwaitinfo(&mask
, &info
);
580 if (errno
!= EINTR
) {
581 PERROR("sigwaitinfo");
584 } else if (signr
== LTTNG_CONSUMER_SIG_SWITCH
) {
585 metadata_switch_timer(ctx
, info
.si_signo
, &info
, NULL
);
586 } else if (signr
== LTTNG_CONSUMER_SIG_TEARDOWN
) {
588 CMM_STORE_SHARED(timer_signal
.qs_done
, 1);
590 DBG("Signal timer metadata thread teardown");
591 } else if (signr
== LTTNG_CONSUMER_SIG_LIVE
) {
592 live_timer(ctx
, info
.si_signo
, &info
, NULL
);
594 ERR("Unexpected signal %d\n", info
.si_signo
);
599 /* Only reached in testpoint error */
601 health_unregister(health_consumerd
);
603 rcu_unregister_thread();