2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License, version 2 only,
6 * as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
13 * You should have received a copy of the GNU General Public License along
14 * with this program; if not, write to the Free Software Foundation, Inc.,
15 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
26 #include <common/common.h>
27 #include <common/consumer/consumer.h>
28 #include <common/defaults.h>
31 #include "health-sessiond.h"
32 #include "ust-consumer.h"
33 #include "lttng-ust-error.h"
34 #include "buffer-registry.h"
36 #include "lttng-sessiond.h"
39 * Return allocated full pathname of the session using the consumer trace path
40 * and subdir if available. On a successful allocation, the directory of the
41 * trace is created with the session credentials.
43 * The caller can safely free(3) the returned value. On error, NULL is
46 static char *setup_trace_path(struct consumer_output
*consumer
,
47 struct ust_app_session
*ua_sess
)
57 /* Allocate our self the string to make sure we never exceed PATH_MAX. */
58 pathname
= zmalloc(PATH_MAX
);
63 /* Get correct path name destination */
64 if (consumer
->type
== CONSUMER_DST_LOCAL
) {
65 /* Set application path to the destination path */
66 ret
= snprintf(pathname
, PATH_MAX
, "%s%s%s",
67 consumer
->dst
.trace_path
, consumer
->subdir
, ua_sess
->path
);
69 PERROR("snprintf channel path");
73 /* Create directory. Ignore if exist. */
74 ret
= run_as_mkdir_recursive(pathname
, S_IRWXU
| S_IRWXG
,
75 ua_sess
->euid
, ua_sess
->egid
);
77 if (errno
!= EEXIST
) {
78 ERR("Trace directory creation error");
83 ret
= snprintf(pathname
, PATH_MAX
, "%s%s", consumer
->subdir
,
86 PERROR("snprintf channel path");
99 * Send a single channel to the consumer using command ASK_CHANNEL_CREATION.
101 * Consumer socket lock MUST be acquired before calling this.
103 static int ask_channel_creation(struct ust_app_session
*ua_sess
,
104 struct ust_app_channel
*ua_chan
, struct consumer_output
*consumer
,
105 struct consumer_socket
*socket
, struct ust_registry_session
*registry
)
109 uint64_t key
, chan_reg_key
;
110 char *pathname
= NULL
;
111 struct lttcomm_consumer_msg msg
;
112 struct ust_registry_channel
*chan_reg
;
113 char shm_path
[PATH_MAX
] = "";
114 char root_shm_path
[PATH_MAX
] = "";
122 DBG2("Asking UST consumer for channel");
124 /* Get and create full trace path of session. */
125 if (ua_sess
->output_traces
) {
126 pathname
= setup_trace_path(consumer
, ua_sess
);
133 /* Depending on the buffer type, a different channel key is used. */
134 if (ua_sess
->buffer_type
== LTTNG_BUFFER_PER_UID
) {
135 chan_reg_key
= ua_chan
->tracing_channel_id
;
137 chan_reg_key
= ua_chan
->key
;
140 if (ua_chan
->attr
.type
== LTTNG_UST_CHAN_METADATA
) {
143 * Metadata channels shm_path (buffers) are handled within
144 * session daemon. Consumer daemon should not try to create
145 * those buffer files.
148 chan_reg
= ust_registry_channel_find(registry
, chan_reg_key
);
150 chan_id
= chan_reg
->chan_id
;
151 if (ua_sess
->shm_path
[0]) {
152 strncpy(shm_path
, ua_sess
->shm_path
, sizeof(shm_path
));
153 shm_path
[sizeof(shm_path
) - 1] = '\0';
154 strncat(shm_path
, "/",
155 sizeof(shm_path
) - strlen(shm_path
) - 1);
156 strncat(shm_path
, ua_chan
->name
,
157 sizeof(shm_path
) - strlen(shm_path
) - 1);
158 strncat(shm_path
, "_",
159 sizeof(shm_path
) - strlen(shm_path
) - 1);
161 strncpy(root_shm_path
, ua_sess
->root_shm_path
, sizeof(root_shm_path
));
162 root_shm_path
[sizeof(root_shm_path
) - 1] = '\0';
165 switch (ua_chan
->attr
.output
) {
168 output
= LTTNG_EVENT_MMAP
;
172 consumer_init_ask_channel_comm_msg(&msg
,
173 ua_chan
->attr
.subbuf_size
,
174 ua_chan
->attr
.num_subbuf
,
175 ua_chan
->attr
.overwrite
,
176 ua_chan
->attr
.switch_timer_interval
,
177 ua_chan
->attr
.read_timer_interval
,
178 ua_sess
->live_timer_interval
,
179 ua_chan
->monitor_timer_interval
,
181 (int) ua_chan
->attr
.type
,
187 consumer
->net_seq_index
,
191 ua_chan
->tracefile_size
,
192 ua_chan
->tracefile_count
,
194 ua_sess
->output_traces
,
196 ua_chan
->attr
.blocking_timeout
,
197 root_shm_path
, shm_path
);
199 health_code_update();
201 ret
= consumer_socket_send(socket
, &msg
, sizeof(msg
));
206 ret
= consumer_recv_status_channel(socket
, &key
,
207 &ua_chan
->expected_stream_count
);
211 /* Communication protocol error. */
212 assert(key
== ua_chan
->key
);
213 /* We need at least one where 1 stream for 1 cpu. */
214 if (ua_sess
->output_traces
) {
215 assert(ua_chan
->expected_stream_count
> 0);
218 DBG2("UST ask channel %" PRIu64
" successfully done with %u stream(s)", key
,
219 ua_chan
->expected_stream_count
);
223 health_code_update();
228 * Ask consumer to create a channel for a given session.
230 * Session list and rcu read side locks must be held by the caller.
232 * Returns 0 on success else a negative value.
234 int ust_consumer_ask_channel(struct ust_app_session
*ua_sess
,
235 struct ust_app_channel
*ua_chan
, struct consumer_output
*consumer
,
236 struct consumer_socket
*socket
, struct ust_registry_session
*registry
)
239 struct ltt_session
*session
;
247 if (!consumer
->enabled
) {
248 ret
= -LTTNG_ERR_NO_CONSUMER
;
249 DBG3("Consumer is disabled");
253 session
= session_find_by_id(ua_sess
->tracing_id
);
256 pthread_mutex_lock(socket
->lock
);
257 ret
= ask_channel_creation(ua_sess
, ua_chan
, consumer
, socket
, registry
);
258 pthread_mutex_unlock(socket
->lock
);
260 ERR("ask_channel_creation consumer command failed");
269 * Send a get channel command to consumer using the given channel key. The
270 * channel object is populated and the stream list.
272 * Return 0 on success else a negative value.
274 int ust_consumer_get_channel(struct consumer_socket
*socket
,
275 struct ust_app_channel
*ua_chan
)
278 struct lttcomm_consumer_msg msg
;
283 memset(&msg
, 0, sizeof(msg
));
284 msg
.cmd_type
= LTTNG_CONSUMER_GET_CHANNEL
;
285 msg
.u
.get_channel
.key
= ua_chan
->key
;
287 pthread_mutex_lock(socket
->lock
);
288 health_code_update();
290 /* Send command and wait for OK reply. */
291 ret
= consumer_send_msg(socket
, &msg
);
296 /* First, get the channel from consumer. */
297 ret
= ustctl_recv_channel_from_consumer(*socket
->fd_ptr
, &ua_chan
->obj
);
300 ERR("Error recv channel from consumer %d with ret %d",
301 *socket
->fd_ptr
, ret
);
303 DBG3("UST app recv channel from consumer. Consumer is dead.");
308 /* Next, get all streams. */
310 struct ust_app_stream
*stream
;
312 /* Create UST stream */
313 stream
= ust_app_alloc_stream();
314 if (stream
== NULL
) {
319 /* Stream object is populated by this call if successful. */
320 ret
= ustctl_recv_stream_from_consumer(*socket
->fd_ptr
, &stream
->obj
);
323 if (ret
== -LTTNG_UST_ERR_NOENT
) {
324 DBG3("UST app consumer has no more stream available");
328 ERR("Recv stream from consumer %d with ret %d",
329 *socket
->fd_ptr
, ret
);
331 DBG3("UST app recv stream from consumer. Consumer is dead.");
336 /* Order is important this is why a list is used. */
337 cds_list_add_tail(&stream
->list
, &ua_chan
->streams
.head
);
338 ua_chan
->streams
.count
++;
340 DBG2("UST app stream %d received successfully", ua_chan
->streams
.count
);
343 /* This MUST match or else we have a synchronization problem. */
344 assert(ua_chan
->expected_stream_count
== ua_chan
->streams
.count
);
346 /* Wait for confirmation that we can proceed with the streams. */
347 ret
= consumer_recv_status_reply(socket
);
353 health_code_update();
354 pthread_mutex_unlock(socket
->lock
);
359 * Send a destroy channel command to consumer using the given channel key.
361 * Note that this command MUST be used prior to a successful
362 * LTTNG_CONSUMER_GET_CHANNEL because once this command is done successfully,
363 * the streams are dispatched to the consumer threads and MUST be teardown
364 * through the hang up process.
366 * Return 0 on success else a negative value.
368 int ust_consumer_destroy_channel(struct consumer_socket
*socket
,
369 struct ust_app_channel
*ua_chan
)
372 struct lttcomm_consumer_msg msg
;
377 memset(&msg
, 0, sizeof(msg
));
378 msg
.cmd_type
= LTTNG_CONSUMER_DESTROY_CHANNEL
;
379 msg
.u
.destroy_channel
.key
= ua_chan
->key
;
381 pthread_mutex_lock(socket
->lock
);
382 health_code_update();
384 ret
= consumer_send_msg(socket
, &msg
);
390 health_code_update();
391 pthread_mutex_unlock(socket
->lock
);
396 * Send a given stream to UST tracer.
398 * On success return 0 else a negative value.
400 int ust_consumer_send_stream_to_ust(struct ust_app
*app
,
401 struct ust_app_channel
*channel
, struct ust_app_stream
*stream
)
409 DBG2("UST consumer send stream to app %d", app
->sock
);
411 /* Relay stream to application. */
412 pthread_mutex_lock(&app
->sock_lock
);
413 ret
= ustctl_send_stream_to_ust(app
->sock
, channel
->obj
, stream
->obj
);
414 pthread_mutex_unlock(&app
->sock_lock
);
416 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
417 ERR("ustctl send stream handle %d to app pid: %d with ret %d",
418 stream
->obj
->handle
, app
->pid
, ret
);
420 DBG3("UST app send stream to ust failed. Application is dead.");
424 channel
->handle
= channel
->obj
->handle
;
431 * Send channel previously received from the consumer to the UST tracer.
433 * On success return 0 else a negative value.
435 int ust_consumer_send_channel_to_ust(struct ust_app
*app
,
436 struct ust_app_session
*ua_sess
, struct ust_app_channel
*channel
)
443 assert(channel
->obj
);
445 DBG2("UST app send channel to sock %d pid %d (name: %s, key: %" PRIu64
")",
446 app
->sock
, app
->pid
, channel
->name
, channel
->tracing_channel_id
);
448 /* Send stream to application. */
449 pthread_mutex_lock(&app
->sock_lock
);
450 ret
= ustctl_send_channel_to_ust(app
->sock
, ua_sess
->handle
, channel
->obj
);
451 pthread_mutex_unlock(&app
->sock_lock
);
453 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
454 ERR("Error ustctl send channel %s to app pid: %d with ret %d",
455 channel
->name
, app
->pid
, ret
);
457 DBG3("UST app send channel to ust failed. Application is dead.");
467 * Handle the metadata requests from the UST consumer
469 * Return 0 on success else a negative value.
471 int ust_consumer_metadata_request(struct consumer_socket
*socket
)
475 struct lttcomm_metadata_request_msg request
;
476 struct buffer_reg_uid
*reg_uid
;
477 struct ust_registry_session
*ust_reg
;
478 struct lttcomm_consumer_msg msg
;
483 health_code_update();
485 /* Wait for a metadata request */
486 pthread_mutex_lock(socket
->lock
);
487 ret
= consumer_socket_recv(socket
, &request
, sizeof(request
));
488 pthread_mutex_unlock(socket
->lock
);
493 DBG("Metadata request received for session %" PRIu64
", key %" PRIu64
,
494 request
.session_id
, request
.key
);
496 reg_uid
= buffer_reg_uid_find(request
.session_id
,
497 request
.bits_per_long
, request
.uid
);
499 ust_reg
= reg_uid
->registry
->reg
.ust
;
501 struct buffer_reg_pid
*reg_pid
=
502 buffer_reg_pid_find(request
.session_id_per_pid
);
504 DBG("PID registry not found for session id %" PRIu64
,
505 request
.session_id_per_pid
);
507 memset(&msg
, 0, sizeof(msg
));
508 msg
.cmd_type
= LTTNG_ERR_UND
;
509 pthread_mutex_lock(socket
->lock
);
510 (void) consumer_send_msg(socket
, &msg
);
511 pthread_mutex_unlock(socket
->lock
);
513 * This is possible since the session might have been destroyed
514 * during a consumer metadata request. So here, return gracefully
515 * because the destroy session will push the remaining metadata to
521 ust_reg
= reg_pid
->registry
->reg
.ust
;
525 pthread_mutex_lock(&ust_reg
->lock
);
526 ret_push
= ust_app_push_metadata(ust_reg
, socket
, 1);
527 pthread_mutex_unlock(&ust_reg
->lock
);
528 if (ret_push
== -EPIPE
) {
529 DBG("Application or relay closed while pushing metadata");
530 } else if (ret_push
< 0) {
531 ERR("Pushing metadata");
535 DBG("UST Consumer metadata pushed successfully");