2 * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
4 * SPDX-License-Identifier: GPL-2.0-only
15 #include <common/compat/errno.h>
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_sess
->live_timer_interval
!= 0,
140 ua_chan
->monitor_timer_interval
,
142 (int) ua_chan
->attr
.type
,
144 &pathname
[consumer_path_offset
],
146 consumer
->net_seq_index
,
150 ua_chan
->tracefile_size
,
151 ua_chan
->tracefile_count
,
153 ua_sess
->output_traces
,
154 lttng_credentials_get_uid(&ua_sess
->real_credentials
),
155 ua_chan
->attr
.blocking_timeout
,
156 root_shm_path
, shm_path
,
158 &ua_sess
->effective_credentials
);
160 health_code_update();
162 ret
= consumer_socket_send(socket
, &msg
, sizeof(msg
));
167 ret
= consumer_recv_status_channel(socket
, &key
,
168 &ua_chan
->expected_stream_count
);
172 /* Communication protocol error. */
173 assert(key
== ua_chan
->key
);
174 /* We need at least one where 1 stream for 1 cpu. */
175 if (ua_sess
->output_traces
) {
176 assert(ua_chan
->expected_stream_count
> 0);
179 DBG2("UST ask channel %" PRIu64
" successfully done with %u stream(s)", key
,
180 ua_chan
->expected_stream_count
);
184 health_code_update();
189 * Ask consumer to create a channel for a given session.
191 * Session list and rcu read side locks must be held by the caller.
193 * Returns 0 on success else a negative value.
195 int ust_consumer_ask_channel(struct ust_app_session
*ua_sess
,
196 struct ust_app_channel
*ua_chan
,
197 struct consumer_output
*consumer
,
198 struct consumer_socket
*socket
,
199 struct ust_registry_session
*registry
,
200 struct lttng_trace_chunk
* trace_chunk
)
210 if (!consumer
->enabled
) {
211 ret
= -LTTNG_ERR_NO_CONSUMER
;
212 DBG3("Consumer is disabled");
216 pthread_mutex_lock(socket
->lock
);
217 ret
= ask_channel_creation(ua_sess
, ua_chan
, consumer
, socket
, registry
,
219 pthread_mutex_unlock(socket
->lock
);
221 ERR("ask_channel_creation consumer command failed");
230 * Send a get channel command to consumer using the given channel key. The
231 * channel object is populated and the stream list.
233 * Return 0 on success else a negative value.
235 int ust_consumer_get_channel(struct consumer_socket
*socket
,
236 struct ust_app_channel
*ua_chan
)
239 struct lttcomm_consumer_msg msg
;
244 memset(&msg
, 0, sizeof(msg
));
245 msg
.cmd_type
= LTTNG_CONSUMER_GET_CHANNEL
;
246 msg
.u
.get_channel
.key
= ua_chan
->key
;
248 pthread_mutex_lock(socket
->lock
);
249 health_code_update();
251 /* Send command and wait for OK reply. */
252 ret
= consumer_send_msg(socket
, &msg
);
257 /* First, get the channel from consumer. */
258 ret
= ustctl_recv_channel_from_consumer(*socket
->fd_ptr
, &ua_chan
->obj
);
261 ERR("Error recv channel from consumer %d with ret %d",
262 *socket
->fd_ptr
, ret
);
264 DBG3("UST app recv channel from consumer. Consumer is dead.");
269 /* Next, get all streams. */
271 struct ust_app_stream
*stream
;
273 /* Create UST stream */
274 stream
= ust_app_alloc_stream();
275 if (stream
== NULL
) {
280 /* Stream object is populated by this call if successful. */
281 ret
= ustctl_recv_stream_from_consumer(*socket
->fd_ptr
, &stream
->obj
);
284 if (ret
== -LTTNG_UST_ERR_NOENT
) {
285 DBG3("UST app consumer has no more stream available");
289 ERR("Recv stream from consumer %d with ret %d",
290 *socket
->fd_ptr
, ret
);
292 DBG3("UST app recv stream from consumer. Consumer is dead.");
297 /* Order is important this is why a list is used. */
298 cds_list_add_tail(&stream
->list
, &ua_chan
->streams
.head
);
299 ua_chan
->streams
.count
++;
301 DBG2("UST app stream %d received successfully", ua_chan
->streams
.count
);
304 /* This MUST match or else we have a synchronization problem. */
305 assert(ua_chan
->expected_stream_count
== ua_chan
->streams
.count
);
307 /* Wait for confirmation that we can proceed with the streams. */
308 ret
= consumer_recv_status_reply(socket
);
314 health_code_update();
315 pthread_mutex_unlock(socket
->lock
);
320 * Send a destroy channel command to consumer using the given channel key.
322 * Note that this command MUST be used prior to a successful
323 * LTTNG_CONSUMER_GET_CHANNEL because once this command is done successfully,
324 * the streams are dispatched to the consumer threads and MUST be teardown
325 * through the hang up process.
327 * Return 0 on success else a negative value.
329 int ust_consumer_destroy_channel(struct consumer_socket
*socket
,
330 struct ust_app_channel
*ua_chan
)
333 struct lttcomm_consumer_msg msg
;
338 memset(&msg
, 0, sizeof(msg
));
339 msg
.cmd_type
= LTTNG_CONSUMER_DESTROY_CHANNEL
;
340 msg
.u
.destroy_channel
.key
= ua_chan
->key
;
342 pthread_mutex_lock(socket
->lock
);
343 health_code_update();
345 ret
= consumer_send_msg(socket
, &msg
);
351 health_code_update();
352 pthread_mutex_unlock(socket
->lock
);
357 * Send a given stream to UST tracer.
359 * On success return 0 else a negative value.
361 int ust_consumer_send_stream_to_ust(struct ust_app
*app
,
362 struct ust_app_channel
*channel
, struct ust_app_stream
*stream
)
370 DBG2("UST consumer send stream to app %d", app
->sock
);
372 /* Relay stream to application. */
373 pthread_mutex_lock(&app
->sock_lock
);
374 ret
= ustctl_send_stream_to_ust(app
->sock
, channel
->obj
, stream
->obj
);
375 pthread_mutex_unlock(&app
->sock_lock
);
377 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
378 ERR("ustctl send stream handle %d to app pid: %d with ret %d",
379 stream
->obj
->handle
, app
->pid
, ret
);
381 DBG3("UST app send stream to ust failed. Application is dead.");
385 channel
->handle
= channel
->obj
->handle
;
392 * Send channel previously received from the consumer to the UST tracer.
394 * On success return 0 else a negative value.
396 int ust_consumer_send_channel_to_ust(struct ust_app
*app
,
397 struct ust_app_session
*ua_sess
, struct ust_app_channel
*channel
)
404 assert(channel
->obj
);
406 DBG2("UST app send channel to sock %d pid %d (name: %s, key: %" PRIu64
")",
407 app
->sock
, app
->pid
, channel
->name
, channel
->tracing_channel_id
);
409 /* Send stream to application. */
410 pthread_mutex_lock(&app
->sock_lock
);
411 ret
= ustctl_send_channel_to_ust(app
->sock
, ua_sess
->handle
, channel
->obj
);
412 pthread_mutex_unlock(&app
->sock_lock
);
414 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
415 ERR("Error ustctl send channel %s to app pid: %d with ret %d",
416 channel
->name
, app
->pid
, ret
);
418 DBG3("UST app send channel to ust failed. Application is dead.");
428 * Handle the metadata requests from the UST consumer
430 * Return 0 on success else a negative value.
432 int ust_consumer_metadata_request(struct consumer_socket
*socket
)
436 struct lttcomm_metadata_request_msg request
;
437 struct buffer_reg_uid
*reg_uid
;
438 struct ust_registry_session
*ust_reg
;
439 struct lttcomm_consumer_msg msg
;
444 health_code_update();
446 /* Wait for a metadata request */
447 pthread_mutex_lock(socket
->lock
);
448 ret
= consumer_socket_recv(socket
, &request
, sizeof(request
));
449 pthread_mutex_unlock(socket
->lock
);
454 DBG("Metadata request received for session %" PRIu64
", key %" PRIu64
,
455 request
.session_id
, request
.key
);
457 reg_uid
= buffer_reg_uid_find(request
.session_id
,
458 request
.bits_per_long
, request
.uid
);
460 ust_reg
= reg_uid
->registry
->reg
.ust
;
462 struct buffer_reg_pid
*reg_pid
=
463 buffer_reg_pid_find(request
.session_id_per_pid
);
465 DBG("PID registry not found for session id %" PRIu64
,
466 request
.session_id_per_pid
);
468 memset(&msg
, 0, sizeof(msg
));
469 msg
.cmd_type
= LTTNG_ERR_UND
;
470 pthread_mutex_lock(socket
->lock
);
471 (void) consumer_send_msg(socket
, &msg
);
472 pthread_mutex_unlock(socket
->lock
);
474 * This is possible since the session might have been destroyed
475 * during a consumer metadata request. So here, return gracefully
476 * because the destroy session will push the remaining metadata to
482 ust_reg
= reg_pid
->registry
->reg
.ust
;
486 pthread_mutex_lock(&ust_reg
->lock
);
487 ret_push
= ust_app_push_metadata(ust_reg
, socket
, 1);
488 pthread_mutex_unlock(&ust_reg
->lock
);
489 if (ret_push
== -EPIPE
) {
490 DBG("Application or relay closed while pushing metadata");
491 } else if (ret_push
< 0) {
492 ERR("Pushing metadata");
496 DBG("UST Consumer metadata pushed successfully");