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 "buffer-registry.h"
35 #include "lttng-sessiond.h"
38 * Return allocated full pathname of the session using the consumer trace path
39 * and subdir if available. On a successful allocation, the directory of the
40 * trace is created with the session credentials.
42 * The caller can safely free(3) the returned value. On error, NULL is
45 static char *setup_trace_path(struct consumer_output
*consumer
,
46 struct ust_app_session
*ua_sess
)
56 /* Allocate our self the string to make sure we never exceed PATH_MAX. */
57 pathname
= zmalloc(PATH_MAX
);
62 /* Get correct path name destination */
63 if (consumer
->type
== CONSUMER_DST_LOCAL
) {
64 /* Set application path to the destination path */
65 ret
= snprintf(pathname
, PATH_MAX
, "%s%s%s%s",
66 consumer
->dst
.session_root_path
,
68 consumer
->subdir
, ua_sess
->path
);
70 PERROR("snprintf channel path");
74 /* Create directory. Ignore if exist. */
75 ret
= run_as_mkdir_recursive(pathname
, S_IRWXU
| S_IRWXG
,
76 ua_sess
->euid
, ua_sess
->egid
);
78 if (errno
!= EEXIST
) {
79 ERR("Trace directory creation error");
84 ret
= snprintf(pathname
, PATH_MAX
, "%s%s", consumer
->subdir
,
87 PERROR("snprintf channel path");
100 * Send a single channel to the consumer using command ASK_CHANNEL_CREATION.
102 * Consumer socket lock MUST be acquired before calling this.
104 static int ask_channel_creation(struct ust_app_session
*ua_sess
,
105 struct ust_app_channel
*ua_chan
, struct consumer_output
*consumer
,
106 struct consumer_socket
*socket
, struct ust_registry_session
*registry
)
110 uint64_t key
, chan_reg_key
;
111 char *pathname
= NULL
;
112 struct lttcomm_consumer_msg msg
;
113 struct ust_registry_channel
*chan_reg
;
114 char shm_path
[PATH_MAX
] = "";
115 char root_shm_path
[PATH_MAX
] = "";
123 DBG2("Asking UST consumer for channel");
125 /* Get and create full trace path of session. */
126 if (ua_sess
->output_traces
) {
127 pathname
= setup_trace_path(consumer
, ua_sess
);
134 /* Depending on the buffer type, a different channel key is used. */
135 if (ua_sess
->buffer_type
== LTTNG_BUFFER_PER_UID
) {
136 chan_reg_key
= ua_chan
->tracing_channel_id
;
138 chan_reg_key
= ua_chan
->key
;
141 if (ua_chan
->attr
.type
== LTTNG_UST_CHAN_METADATA
) {
144 * Metadata channels shm_path (buffers) are handled within
145 * session daemon. Consumer daemon should not try to create
146 * those buffer files.
149 chan_reg
= ust_registry_channel_find(registry
, chan_reg_key
);
151 chan_id
= chan_reg
->chan_id
;
152 if (ua_sess
->shm_path
[0]) {
153 strncpy(shm_path
, ua_sess
->shm_path
, sizeof(shm_path
));
154 shm_path
[sizeof(shm_path
) - 1] = '\0';
155 strncat(shm_path
, "/",
156 sizeof(shm_path
) - strlen(shm_path
) - 1);
157 strncat(shm_path
, ua_chan
->name
,
158 sizeof(shm_path
) - strlen(shm_path
) - 1);
159 strncat(shm_path
, "_",
160 sizeof(shm_path
) - strlen(shm_path
) - 1);
162 strncpy(root_shm_path
, ua_sess
->root_shm_path
, sizeof(root_shm_path
));
163 root_shm_path
[sizeof(root_shm_path
) - 1] = '\0';
166 switch (ua_chan
->attr
.output
) {
169 output
= LTTNG_EVENT_MMAP
;
173 consumer_init_ask_channel_comm_msg(&msg
,
174 ua_chan
->attr
.subbuf_size
,
175 ua_chan
->attr
.num_subbuf
,
176 ua_chan
->attr
.overwrite
,
177 ua_chan
->attr
.switch_timer_interval
,
178 ua_chan
->attr
.read_timer_interval
,
179 ua_sess
->live_timer_interval
,
180 ua_chan
->monitor_timer_interval
,
182 (int) ua_chan
->attr
.type
,
188 consumer
->net_seq_index
,
192 ua_chan
->tracefile_size
,
193 ua_chan
->tracefile_count
,
195 ua_sess
->output_traces
,
197 ua_chan
->attr
.blocking_timeout
,
198 root_shm_path
, shm_path
);
200 health_code_update();
202 ret
= consumer_socket_send(socket
, &msg
, sizeof(msg
));
207 ret
= consumer_recv_status_channel(socket
, &key
,
208 &ua_chan
->expected_stream_count
);
212 /* Communication protocol error. */
213 assert(key
== ua_chan
->key
);
214 /* We need at least one where 1 stream for 1 cpu. */
215 if (ua_sess
->output_traces
) {
216 assert(ua_chan
->expected_stream_count
> 0);
219 DBG2("UST ask channel %" PRIu64
" successfully done with %u stream(s)", key
,
220 ua_chan
->expected_stream_count
);
224 health_code_update();
229 * Ask consumer to create a channel for a given session.
231 * Session list and rcu read side locks must be held by the caller.
233 * Returns 0 on success else a negative value.
235 int ust_consumer_ask_channel(struct ust_app_session
*ua_sess
,
236 struct ust_app_channel
*ua_chan
, struct consumer_output
*consumer
,
237 struct consumer_socket
*socket
, struct ust_registry_session
*registry
)
240 struct ltt_session
*session
;
248 if (!consumer
->enabled
) {
249 ret
= -LTTNG_ERR_NO_CONSUMER
;
250 DBG3("Consumer is disabled");
254 session
= session_find_by_id(ua_sess
->tracing_id
);
257 pthread_mutex_lock(socket
->lock
);
258 ret
= ask_channel_creation(ua_sess
, ua_chan
, consumer
, socket
, registry
);
259 pthread_mutex_unlock(socket
->lock
);
261 ERR("ask_channel_creation consumer command failed");
270 * Send a get channel command to consumer using the given channel key. The
271 * channel object is populated and the stream list.
273 * Return 0 on success else a negative value.
275 int ust_consumer_get_channel(struct consumer_socket
*socket
,
276 struct ust_app_channel
*ua_chan
)
279 struct lttcomm_consumer_msg msg
;
284 memset(&msg
, 0, sizeof(msg
));
285 msg
.cmd_type
= LTTNG_CONSUMER_GET_CHANNEL
;
286 msg
.u
.get_channel
.key
= ua_chan
->key
;
288 pthread_mutex_lock(socket
->lock
);
289 health_code_update();
291 /* Send command and wait for OK reply. */
292 ret
= consumer_send_msg(socket
, &msg
);
297 /* First, get the channel from consumer. */
298 ret
= ustctl_recv_channel_from_consumer(*socket
->fd_ptr
, &ua_chan
->obj
);
301 ERR("Error recv channel from consumer %d with ret %d",
302 *socket
->fd_ptr
, ret
);
304 DBG3("UST app recv channel from consumer. Consumer is dead.");
309 /* Next, get all streams. */
311 struct ust_app_stream
*stream
;
313 /* Create UST stream */
314 stream
= ust_app_alloc_stream();
315 if (stream
== NULL
) {
320 /* Stream object is populated by this call if successful. */
321 ret
= ustctl_recv_stream_from_consumer(*socket
->fd_ptr
, &stream
->obj
);
324 if (ret
== -LTTNG_UST_ERR_NOENT
) {
325 DBG3("UST app consumer has no more stream available");
329 ERR("Recv stream from consumer %d with ret %d",
330 *socket
->fd_ptr
, ret
);
332 DBG3("UST app recv stream from consumer. Consumer is dead.");
337 /* Order is important this is why a list is used. */
338 cds_list_add_tail(&stream
->list
, &ua_chan
->streams
.head
);
339 ua_chan
->streams
.count
++;
341 DBG2("UST app stream %d received successfully", ua_chan
->streams
.count
);
344 /* This MUST match or else we have a synchronization problem. */
345 assert(ua_chan
->expected_stream_count
== ua_chan
->streams
.count
);
347 /* Wait for confirmation that we can proceed with the streams. */
348 ret
= consumer_recv_status_reply(socket
);
354 health_code_update();
355 pthread_mutex_unlock(socket
->lock
);
360 * Send a destroy channel command to consumer using the given channel key.
362 * Note that this command MUST be used prior to a successful
363 * LTTNG_CONSUMER_GET_CHANNEL because once this command is done successfully,
364 * the streams are dispatched to the consumer threads and MUST be teardown
365 * through the hang up process.
367 * Return 0 on success else a negative value.
369 int ust_consumer_destroy_channel(struct consumer_socket
*socket
,
370 struct ust_app_channel
*ua_chan
)
373 struct lttcomm_consumer_msg msg
;
378 memset(&msg
, 0, sizeof(msg
));
379 msg
.cmd_type
= LTTNG_CONSUMER_DESTROY_CHANNEL
;
380 msg
.u
.destroy_channel
.key
= ua_chan
->key
;
382 pthread_mutex_lock(socket
->lock
);
383 health_code_update();
385 ret
= consumer_send_msg(socket
, &msg
);
391 health_code_update();
392 pthread_mutex_unlock(socket
->lock
);
397 * Send a given stream to UST tracer.
399 * On success return 0 else a negative value.
401 int ust_consumer_send_stream_to_ust(struct ust_app
*app
,
402 struct ust_app_channel
*channel
, struct ust_app_stream
*stream
)
410 DBG2("UST consumer send stream to app %d", app
->sock
);
412 /* Relay stream to application. */
413 pthread_mutex_lock(&app
->sock_lock
);
414 ret
= ustctl_send_stream_to_ust(app
->sock
, channel
->obj
, stream
->obj
);
415 pthread_mutex_unlock(&app
->sock_lock
);
417 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
418 ERR("ustctl send stream handle %d to app pid: %d with ret %d",
419 stream
->obj
->handle
, app
->pid
, ret
);
421 DBG3("UST app send stream to ust failed. Application is dead.");
425 channel
->handle
= channel
->obj
->handle
;
432 * Send channel previously received from the consumer to the UST tracer.
434 * On success return 0 else a negative value.
436 int ust_consumer_send_channel_to_ust(struct ust_app
*app
,
437 struct ust_app_session
*ua_sess
, struct ust_app_channel
*channel
)
444 assert(channel
->obj
);
446 DBG2("UST app send channel to sock %d pid %d (name: %s, key: %" PRIu64
")",
447 app
->sock
, app
->pid
, channel
->name
, channel
->tracing_channel_id
);
449 /* Send stream to application. */
450 pthread_mutex_lock(&app
->sock_lock
);
451 ret
= ustctl_send_channel_to_ust(app
->sock
, ua_sess
->handle
, channel
->obj
);
452 pthread_mutex_unlock(&app
->sock_lock
);
454 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
455 ERR("Error ustctl send channel %s to app pid: %d with ret %d",
456 channel
->name
, app
->pid
, ret
);
458 DBG3("UST app send channel to ust failed. Application is dead.");
468 * Handle the metadata requests from the UST consumer
470 * Return 0 on success else a negative value.
472 int ust_consumer_metadata_request(struct consumer_socket
*socket
)
476 struct lttcomm_metadata_request_msg request
;
477 struct buffer_reg_uid
*reg_uid
;
478 struct ust_registry_session
*ust_reg
;
479 struct lttcomm_consumer_msg msg
;
484 health_code_update();
486 /* Wait for a metadata request */
487 pthread_mutex_lock(socket
->lock
);
488 ret
= consumer_socket_recv(socket
, &request
, sizeof(request
));
489 pthread_mutex_unlock(socket
->lock
);
494 DBG("Metadata request received for session %" PRIu64
", key %" PRIu64
,
495 request
.session_id
, request
.key
);
497 reg_uid
= buffer_reg_uid_find(request
.session_id
,
498 request
.bits_per_long
, request
.uid
);
500 ust_reg
= reg_uid
->registry
->reg
.ust
;
502 struct buffer_reg_pid
*reg_pid
=
503 buffer_reg_pid_find(request
.session_id_per_pid
);
505 DBG("PID registry not found for session id %" PRIu64
,
506 request
.session_id_per_pid
);
508 memset(&msg
, 0, sizeof(msg
));
509 msg
.cmd_type
= LTTNG_ERR_UND
;
510 (void) consumer_send_msg(socket
, &msg
);
512 * This is possible since the session might have been destroyed
513 * during a consumer metadata request. So here, return gracefully
514 * because the destroy session will push the remaining metadata to
520 ust_reg
= reg_pid
->registry
->reg
.ust
;
524 pthread_mutex_lock(&ust_reg
->lock
);
525 ret_push
= ust_app_push_metadata(ust_reg
, socket
, 1);
526 pthread_mutex_unlock(&ust_reg
->lock
);
527 if (ret_push
== -EPIPE
) {
528 DBG("Application or relay closed while pushing metadata");
529 } else if (ret_push
< 0) {
530 ERR("Pushing metadata");
534 DBG("UST Consumer metadata pushed successfully");