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 <common/common.h>
26 #include "consumer-timer.h"
27 #include "ust-consumer/ust-consumer.h"
29 static struct timer_signal_data timer_signal
;
32 * Set custom signal mask to current thread.
34 static void setmask(sigset_t
*mask
)
38 ret
= sigemptyset(mask
);
40 PERROR("sigemptyset");
42 ret
= sigaddset(mask
, LTTNG_CONSUMER_SIG_SWITCH
);
46 ret
= sigaddset(mask
, LTTNG_CONSUMER_SIG_TEARDOWN
);
53 * Execute action on a timer switch.
55 static void metadata_switch_timer(struct lttng_consumer_local_data
*ctx
,
56 int sig
, siginfo_t
*si
, void *uc
)
59 struct lttng_consumer_channel
*channel
;
61 channel
= si
->si_value
.sival_ptr
;
64 DBG("Switch timer for channel %" PRIu64
, channel
->key
);
66 case LTTNG_CONSUMER32_UST
:
67 case LTTNG_CONSUMER64_UST
:
68 ret
= lttng_ustconsumer_request_metadata(ctx
, channel
);
71 * An error means that we were unable to request the metadata to
72 * the session daemon so stop the timer for that channel.
74 consumer_timer_switch_stop(channel
);
77 case LTTNG_CONSUMER_KERNEL
:
78 case LTTNG_CONSUMER_UNKNOWN
:
85 * Set the timer for periodical metadata flush.
87 void consumer_timer_switch_start(struct lttng_consumer_channel
*channel
,
88 unsigned int switch_timer_interval
)
92 struct itimerspec its
;
97 if (switch_timer_interval
== 0) {
101 sev
.sigev_notify
= SIGEV_SIGNAL
;
102 sev
.sigev_signo
= LTTNG_CONSUMER_SIG_SWITCH
;
103 sev
.sigev_value
.sival_ptr
= channel
;
104 ret
= timer_create(CLOCKID
, &sev
, &channel
->switch_timer
);
106 PERROR("timer_create");
108 channel
->switch_timer_enabled
= 1;
110 its
.it_value
.tv_sec
= switch_timer_interval
/ 1000000;
111 its
.it_value
.tv_nsec
= switch_timer_interval
% 1000000;
112 its
.it_interval
.tv_sec
= its
.it_value
.tv_sec
;
113 its
.it_interval
.tv_nsec
= its
.it_value
.tv_nsec
;
115 ret
= timer_settime(channel
->switch_timer
, 0, &its
, NULL
);
117 PERROR("timer_settime");
122 * Stop and delete timer.
124 void consumer_timer_switch_stop(struct lttng_consumer_channel
*channel
)
127 sigset_t pending_set
;
131 ret
= timer_delete(channel
->switch_timer
);
133 PERROR("timer_delete");
136 /* Ensure we don't have any signal queued for this channel. */
138 ret
= sigemptyset(&pending_set
);
140 PERROR("sigemptyset");
142 ret
= sigpending(&pending_set
);
144 PERROR("sigpending");
146 if (!sigismember(&pending_set
, LTTNG_CONSUMER_SIG_SWITCH
)) {
153 * From this point, no new signal handler will be fired that would try to
154 * access "chan". However, we still need to wait for any currently
155 * executing handler to complete.
158 CMM_STORE_SHARED(timer_signal
.qs_done
, 0);
162 * Kill with LTTNG_CONSUMER_SIG_TEARDOWN, so signal management thread wakes
165 kill(getpid(), LTTNG_CONSUMER_SIG_TEARDOWN
);
167 while (!CMM_LOAD_SHARED(timer_signal
.qs_done
)) {
174 * Block the RT signals for the entire process. It must be called from the
175 * consumer main before creating the threads
177 void consumer_signal_init(void)
182 /* Block signal for entire process, so only our thread processes it. */
184 ret
= pthread_sigmask(SIG_BLOCK
, &mask
, NULL
);
187 PERROR("pthread_sigmask");
192 * This thread is the sighandler for signals LTTNG_CONSUMER_SIG_SWITCH and
193 * LTTNG_CONSUMER_SIG_TEARDOWN that are emitted by the periodic timer to check
194 * if new metadata is available.
196 void *consumer_timer_metadata_thread(void *data
)
201 struct lttng_consumer_local_data
*ctx
= data
;
203 /* Only self thread will receive signal mask. */
205 CMM_STORE_SHARED(timer_signal
.tid
, pthread_self());
208 signr
= sigwaitinfo(&mask
, &info
);
210 if (errno
!= EINTR
) {
211 PERROR("sigwaitinfo");
214 } else if (signr
== LTTNG_CONSUMER_SIG_SWITCH
) {
215 metadata_switch_timer(ctx
, info
.si_signo
, &info
, NULL
);
216 } else if (signr
== LTTNG_CONSUMER_SIG_TEARDOWN
) {
218 CMM_STORE_SHARED(timer_signal
.qs_done
, 1);
220 DBG("Signal timer metadata thread teardown");
222 ERR("Unexpected signal %d\n", info
.si_signo
);