2 * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
4 * SPDX-License-Identifier: GPL-2.0-only
16 #include <common/common.h>
17 #include <common/consumer/consumer.h>
18 #include <common/defaults.h>
21 #include "health-sessiond.h"
22 #include "ust-consumer.h"
23 #include "lttng-ust-error.h"
24 #include "buffer-registry.h"
26 #include "lttng-sessiond.h"
29 * Send a single channel to the consumer using command ASK_CHANNEL_CREATION.
31 * Consumer socket lock MUST be acquired before calling this.
33 static int ask_channel_creation(struct ust_app_session
*ua_sess
,
34 struct ust_app_channel
*ua_chan
,
35 struct consumer_output
*consumer
,
36 struct consumer_socket
*socket
,
37 struct ust_registry_session
*registry
,
38 struct lttng_trace_chunk
*trace_chunk
)
42 uint64_t key
, chan_reg_key
;
43 char *pathname
= NULL
;
44 struct lttcomm_consumer_msg msg
;
45 struct ust_registry_channel
*chan_reg
;
46 char shm_path
[PATH_MAX
] = "";
47 char root_shm_path
[PATH_MAX
] = "";
49 size_t consumer_path_offset
= 0;
57 DBG2("Asking UST consumer for channel");
59 is_local_trace
= consumer
->net_seq_index
== -1ULL;
60 /* Format the channel's path (relative to the current trace chunk). */
61 pathname
= setup_channel_trace_path(consumer
, ua_sess
->path
,
62 &consumer_path_offset
);
68 if (is_local_trace
&& trace_chunk
) {
69 enum lttng_trace_chunk_status chunk_status
;
72 ret
= asprintf(&pathname_index
, "%s/" DEFAULT_INDEX_DIR
,
75 ERR("Failed to format channel index directory");
81 * Create the index subdirectory which will take care
82 * of implicitly creating the channel's path.
84 chunk_status
= lttng_trace_chunk_create_subdirectory(
85 trace_chunk
, pathname_index
);
87 if (chunk_status
!= LTTNG_TRACE_CHUNK_STATUS_OK
) {
93 /* Depending on the buffer type, a different channel key is used. */
94 if (ua_sess
->buffer_type
== LTTNG_BUFFER_PER_UID
) {
95 chan_reg_key
= ua_chan
->tracing_channel_id
;
97 chan_reg_key
= ua_chan
->key
;
100 if (ua_chan
->attr
.type
== LTTNG_UST_CHAN_METADATA
) {
103 * Metadata channels shm_path (buffers) are handled within
104 * session daemon. Consumer daemon should not try to create
105 * those buffer files.
108 chan_reg
= ust_registry_channel_find(registry
, chan_reg_key
);
110 chan_id
= chan_reg
->chan_id
;
111 if (ua_sess
->shm_path
[0]) {
112 strncpy(shm_path
, ua_sess
->shm_path
, sizeof(shm_path
));
113 shm_path
[sizeof(shm_path
) - 1] = '\0';
114 strncat(shm_path
, "/",
115 sizeof(shm_path
) - strlen(shm_path
) - 1);
116 strncat(shm_path
, ua_chan
->name
,
117 sizeof(shm_path
) - strlen(shm_path
) - 1);
118 strncat(shm_path
, "_",
119 sizeof(shm_path
) - strlen(shm_path
) - 1);
121 strncpy(root_shm_path
, ua_sess
->root_shm_path
, sizeof(root_shm_path
));
122 root_shm_path
[sizeof(root_shm_path
) - 1] = '\0';
125 switch (ua_chan
->attr
.output
) {
128 output
= LTTNG_EVENT_MMAP
;
132 consumer_init_ask_channel_comm_msg(&msg
,
133 ua_chan
->attr
.subbuf_size
,
134 ua_chan
->attr
.num_subbuf
,
135 ua_chan
->attr
.overwrite
,
136 ua_chan
->attr
.switch_timer_interval
,
137 ua_chan
->attr
.read_timer_interval
,
138 ua_sess
->live_timer_interval
,
139 ua_chan
->monitor_timer_interval
,
141 (int) ua_chan
->attr
.type
,
143 &pathname
[consumer_path_offset
],
145 consumer
->net_seq_index
,
149 ua_chan
->tracefile_size
,
150 ua_chan
->tracefile_count
,
152 ua_sess
->output_traces
,
153 ua_sess
->real_credentials
.uid
,
154 ua_chan
->attr
.blocking_timeout
,
155 root_shm_path
, shm_path
,
157 &ua_sess
->effective_credentials
);
159 health_code_update();
161 ret
= consumer_socket_send(socket
, &msg
, sizeof(msg
));
166 ret
= consumer_recv_status_channel(socket
, &key
,
167 &ua_chan
->expected_stream_count
);
171 /* Communication protocol error. */
172 assert(key
== ua_chan
->key
);
173 /* We need at least one where 1 stream for 1 cpu. */
174 if (ua_sess
->output_traces
) {
175 assert(ua_chan
->expected_stream_count
> 0);
178 DBG2("UST ask channel %" PRIu64
" successfully done with %u stream(s)", key
,
179 ua_chan
->expected_stream_count
);
183 health_code_update();
188 * Ask consumer to create a channel for a given session.
190 * Session list and rcu read side locks must be held by the caller.
192 * Returns 0 on success else a negative value.
194 int ust_consumer_ask_channel(struct ust_app_session
*ua_sess
,
195 struct ust_app_channel
*ua_chan
,
196 struct consumer_output
*consumer
,
197 struct consumer_socket
*socket
,
198 struct ust_registry_session
*registry
,
199 struct lttng_trace_chunk
* trace_chunk
)
209 if (!consumer
->enabled
) {
210 ret
= -LTTNG_ERR_NO_CONSUMER
;
211 DBG3("Consumer is disabled");
215 pthread_mutex_lock(socket
->lock
);
216 ret
= ask_channel_creation(ua_sess
, ua_chan
, consumer
, socket
, registry
,
218 pthread_mutex_unlock(socket
->lock
);
220 ERR("ask_channel_creation consumer command failed");
229 * Send a get channel command to consumer using the given channel key. The
230 * channel object is populated and the stream list.
232 * Return 0 on success else a negative value.
234 int ust_consumer_get_channel(struct consumer_socket
*socket
,
235 struct ust_app_channel
*ua_chan
)
238 struct lttcomm_consumer_msg msg
;
243 memset(&msg
, 0, sizeof(msg
));
244 msg
.cmd_type
= LTTNG_CONSUMER_GET_CHANNEL
;
245 msg
.u
.get_channel
.key
= ua_chan
->key
;
247 pthread_mutex_lock(socket
->lock
);
248 health_code_update();
250 /* Send command and wait for OK reply. */
251 ret
= consumer_send_msg(socket
, &msg
);
256 /* First, get the channel from consumer. */
257 ret
= ustctl_recv_channel_from_consumer(*socket
->fd_ptr
, &ua_chan
->obj
);
260 ERR("Error recv channel from consumer %d with ret %d",
261 *socket
->fd_ptr
, ret
);
263 DBG3("UST app recv channel from consumer. Consumer is dead.");
268 /* Next, get all streams. */
270 struct ust_app_stream
*stream
;
272 /* Create UST stream */
273 stream
= ust_app_alloc_stream();
274 if (stream
== NULL
) {
279 /* Stream object is populated by this call if successful. */
280 ret
= ustctl_recv_stream_from_consumer(*socket
->fd_ptr
, &stream
->obj
);
283 if (ret
== -LTTNG_UST_ERR_NOENT
) {
284 DBG3("UST app consumer has no more stream available");
288 ERR("Recv stream from consumer %d with ret %d",
289 *socket
->fd_ptr
, ret
);
291 DBG3("UST app recv stream from consumer. Consumer is dead.");
296 /* Order is important this is why a list is used. */
297 cds_list_add_tail(&stream
->list
, &ua_chan
->streams
.head
);
298 ua_chan
->streams
.count
++;
300 DBG2("UST app stream %d received successfully", ua_chan
->streams
.count
);
303 /* This MUST match or else we have a synchronization problem. */
304 assert(ua_chan
->expected_stream_count
== ua_chan
->streams
.count
);
306 /* Wait for confirmation that we can proceed with the streams. */
307 ret
= consumer_recv_status_reply(socket
);
313 health_code_update();
314 pthread_mutex_unlock(socket
->lock
);
319 * Send a destroy channel command to consumer using the given channel key.
321 * Note that this command MUST be used prior to a successful
322 * LTTNG_CONSUMER_GET_CHANNEL because once this command is done successfully,
323 * the streams are dispatched to the consumer threads and MUST be teardown
324 * through the hang up process.
326 * Return 0 on success else a negative value.
328 int ust_consumer_destroy_channel(struct consumer_socket
*socket
,
329 struct ust_app_channel
*ua_chan
)
332 struct lttcomm_consumer_msg msg
;
337 memset(&msg
, 0, sizeof(msg
));
338 msg
.cmd_type
= LTTNG_CONSUMER_DESTROY_CHANNEL
;
339 msg
.u
.destroy_channel
.key
= ua_chan
->key
;
341 pthread_mutex_lock(socket
->lock
);
342 health_code_update();
344 ret
= consumer_send_msg(socket
, &msg
);
350 health_code_update();
351 pthread_mutex_unlock(socket
->lock
);
356 * Send a given stream to UST tracer.
358 * On success return 0 else a negative value.
360 int ust_consumer_send_stream_to_ust(struct ust_app
*app
,
361 struct ust_app_channel
*channel
, struct ust_app_stream
*stream
)
369 DBG2("UST consumer send stream to app %d", app
->sock
);
371 /* Relay stream to application. */
372 pthread_mutex_lock(&app
->sock_lock
);
373 ret
= ustctl_send_stream_to_ust(app
->sock
, channel
->obj
, stream
->obj
);
374 pthread_mutex_unlock(&app
->sock_lock
);
376 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
377 ERR("ustctl send stream handle %d to app pid: %d with ret %d",
378 stream
->obj
->handle
, app
->pid
, ret
);
380 DBG3("UST app send stream to ust failed. Application is dead.");
384 channel
->handle
= channel
->obj
->handle
;
391 * Send channel previously received from the consumer to the UST tracer.
393 * On success return 0 else a negative value.
395 int ust_consumer_send_channel_to_ust(struct ust_app
*app
,
396 struct ust_app_session
*ua_sess
, struct ust_app_channel
*channel
)
403 assert(channel
->obj
);
405 DBG2("UST app send channel to sock %d pid %d (name: %s, key: %" PRIu64
")",
406 app
->sock
, app
->pid
, channel
->name
, channel
->tracing_channel_id
);
408 /* Send stream to application. */
409 pthread_mutex_lock(&app
->sock_lock
);
410 ret
= ustctl_send_channel_to_ust(app
->sock
, ua_sess
->handle
, channel
->obj
);
411 pthread_mutex_unlock(&app
->sock_lock
);
413 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
414 ERR("Error ustctl send channel %s to app pid: %d with ret %d",
415 channel
->name
, app
->pid
, ret
);
417 DBG3("UST app send channel to ust failed. Application is dead.");
427 * Handle the metadata requests from the UST consumer
429 * Return 0 on success else a negative value.
431 int ust_consumer_metadata_request(struct consumer_socket
*socket
)
435 struct lttcomm_metadata_request_msg request
;
436 struct buffer_reg_uid
*reg_uid
;
437 struct ust_registry_session
*ust_reg
;
438 struct lttcomm_consumer_msg msg
;
443 health_code_update();
445 /* Wait for a metadata request */
446 pthread_mutex_lock(socket
->lock
);
447 ret
= consumer_socket_recv(socket
, &request
, sizeof(request
));
448 pthread_mutex_unlock(socket
->lock
);
453 DBG("Metadata request received for session %" PRIu64
", key %" PRIu64
,
454 request
.session_id
, request
.key
);
456 reg_uid
= buffer_reg_uid_find(request
.session_id
,
457 request
.bits_per_long
, request
.uid
);
459 ust_reg
= reg_uid
->registry
->reg
.ust
;
461 struct buffer_reg_pid
*reg_pid
=
462 buffer_reg_pid_find(request
.session_id_per_pid
);
464 DBG("PID registry not found for session id %" PRIu64
,
465 request
.session_id_per_pid
);
467 memset(&msg
, 0, sizeof(msg
));
468 msg
.cmd_type
= LTTNG_ERR_UND
;
469 pthread_mutex_lock(socket
->lock
);
470 (void) consumer_send_msg(socket
, &msg
);
471 pthread_mutex_unlock(socket
->lock
);
473 * This is possible since the session might have been destroyed
474 * during a consumer metadata request. So here, return gracefully
475 * because the destroy session will push the remaining metadata to
481 ust_reg
= reg_pid
->registry
->reg
.ust
;
485 pthread_mutex_lock(&ust_reg
->lock
);
486 ret_push
= ust_app_push_metadata(ust_reg
, socket
, 1);
487 pthread_mutex_unlock(&ust_reg
->lock
);
488 if (ret_push
== -EPIPE
) {
489 DBG("Application or relay closed while pushing metadata");
490 } else if (ret_push
< 0) {
491 ERR("Pushing metadata");
495 DBG("UST Consumer metadata pushed successfully");