On-disk multiple tracefiles circular buffer
[lttng-tools.git] / src / bin / lttng-sessiond / ust-consumer.c
CommitLineData
48842b30
DG
1/*
2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
3 *
d14d33bf
AM
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.
48842b30 7 *
d14d33bf
AM
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.
48842b30 12 *
d14d33bf
AM
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.
48842b30
DG
16 */
17
18#define _GNU_SOURCE
19#include <errno.h>
20#include <stdio.h>
21#include <stdlib.h>
22#include <string.h>
23#include <unistd.h>
d88aee68 24#include <inttypes.h>
48842b30 25
990570ed 26#include <common/common.h>
db758600 27#include <common/consumer.h>
990570ed 28#include <common/defaults.h>
48842b30 29
00e2e675 30#include "consumer.h"
7972aab2 31#include "health.h"
48842b30 32#include "ust-consumer.h"
331744e3
JD
33#include "buffer-registry.h"
34#include "session.h"
48842b30
DG
35
36/*
ffe60014
DG
37 * Return allocated full pathname of the session using the consumer trace path
38 * and subdir if available. On a successful allocation, the directory of the
39 * trace is created with the session credentials.
40 *
41 * The caller can safely free(3) the returned value. On error, NULL is
42 * returned.
48842b30 43 */
ffe60014
DG
44static char *setup_trace_path(struct consumer_output *consumer,
45 struct ust_app_session *ua_sess)
48842b30 46{
ffe60014
DG
47 int ret;
48 char *pathname;
37278a1e 49
ffe60014
DG
50 assert(consumer);
51 assert(ua_sess);
00e2e675 52
840cb59c 53 health_code_update();
ca03de58 54
ffe60014
DG
55 /* Allocate our self the string to make sure we never exceed PATH_MAX. */
56 pathname = zmalloc(PATH_MAX);
57 if (!pathname) {
48842b30
DG
58 goto error;
59 }
00e2e675 60
ffe60014
DG
61 /* Get correct path name destination */
62 if (consumer->type == CONSUMER_DST_LOCAL) {
63 /* Set application path to the destination path */
64 ret = snprintf(pathname, PATH_MAX, "%s/%s/%s",
65 consumer->dst.trace_path, consumer->subdir, ua_sess->path);
66 if (ret < 0) {
67 PERROR("snprintf channel path");
68 goto error;
69 }
ca03de58 70
ffe60014 71 /* Create directory. Ignore if exist. */
7972aab2
DG
72 ret = run_as_mkdir_recursive(pathname, S_IRWXU | S_IRWXG,
73 ua_sess->euid, ua_sess->egid);
ffe60014
DG
74 if (ret < 0) {
75 if (ret != -EEXIST) {
76 ERR("Trace directory creation error");
77 goto error;
78 }
79 }
80 } else {
81 ret = snprintf(pathname, PATH_MAX, "%s/%s", consumer->subdir,
82 ua_sess->path);
83 if (ret < 0) {
84 PERROR("snprintf channel path");
85 goto error;
86 }
48842b30
DG
87 }
88
ffe60014 89 return pathname;
ca03de58 90
37278a1e 91error:
ffe60014
DG
92 free(pathname);
93 return NULL;
37278a1e
DG
94}
95
96/*
ffe60014
DG
97 * Send a single channel to the consumer using command ADD_CHANNEL.
98 *
7972aab2 99 * Consumer socket lock MUST be acquired before calling this.
37278a1e 100 */
ffe60014
DG
101static int ask_channel_creation(struct ust_app_session *ua_sess,
102 struct ust_app_channel *ua_chan, struct consumer_output *consumer,
7972aab2 103 struct consumer_socket *socket, struct ust_registry_session *registry)
37278a1e 104{
ffe60014 105 int ret;
7972aab2
DG
106 uint32_t chan_id;
107 uint64_t key, chan_reg_key;
ffe60014 108 char *pathname = NULL;
37278a1e 109 struct lttcomm_consumer_msg msg;
7972aab2 110 struct ust_registry_channel *chan_reg;
37278a1e 111
ffe60014
DG
112 assert(ua_sess);
113 assert(ua_chan);
114 assert(socket);
37278a1e 115 assert(consumer);
7972aab2 116 assert(registry);
ffe60014
DG
117
118 DBG2("Asking UST consumer for channel");
119
120 /* Get and create full trace path of session. */
121 pathname = setup_trace_path(consumer, ua_sess);
122 if (!pathname) {
123 ret = -1;
124 goto error;
125 }
126
7972aab2
DG
127 /* Depending on the buffer type, a different channel key is used. */
128 if (ua_sess->buffer_type == LTTNG_BUFFER_PER_UID) {
129 chan_reg_key = ua_chan->tracing_channel_id;
130 } else {
131 chan_reg_key = ua_chan->key;
132 }
133
134 if (ua_chan->attr.type == LTTNG_UST_CHAN_METADATA) {
135 chan_id = -1U;
136 } else {
137 chan_reg = ust_registry_channel_find(registry, chan_reg_key);
138 assert(chan_reg);
139 chan_id = chan_reg->chan_id;
140 }
141
ffe60014
DG
142 consumer_init_ask_channel_comm_msg(&msg,
143 ua_chan->attr.subbuf_size,
144 ua_chan->attr.num_subbuf,
145 ua_chan->attr.overwrite,
146 ua_chan->attr.switch_timer_interval,
147 ua_chan->attr.read_timer_interval,
148 (int) ua_chan->attr.output,
149 (int) ua_chan->attr.type,
7972aab2 150 ua_sess->tracing_id,
ca22feea 151 pathname,
ffe60014 152 ua_chan->name,
7972aab2
DG
153 ua_sess->euid,
154 ua_sess->egid,
ffe60014
DG
155 consumer->net_seq_index,
156 ua_chan->key,
7972aab2 157 registry->uuid,
1624d5b7
JD
158 chan_id,
159 ua_chan->tracefile_size,
160 ua_chan->tracefile_count);
37278a1e 161
840cb59c 162 health_code_update();
ca03de58 163
ffe60014 164 ret = lttcomm_send_unix_sock(socket->fd, &msg, sizeof(msg));
37278a1e
DG
165 if (ret < 0) {
166 goto error;
167 }
168
ffe60014
DG
169 ret = consumer_recv_status_channel(socket, &key,
170 &ua_chan->expected_stream_count);
171 if (ret < 0) {
172 goto error;
173 }
174 /* Communication protocol error. */
175 assert(key == ua_chan->key);
176 /* We need at least one where 1 stream for 1 cpu. */
177 assert(ua_chan->expected_stream_count > 0);
178
d88aee68 179 DBG2("UST ask channel %" PRIu64 " successfully done with %u stream(s)", key,
ffe60014 180 ua_chan->expected_stream_count);
ca03de58 181
37278a1e 182error:
ffe60014
DG
183 free(pathname);
184 health_code_update();
37278a1e
DG
185 return ret;
186}
187
188/*
ffe60014
DG
189 * Ask consumer to create a channel for a given session.
190 *
191 * Returns 0 on success else a negative value.
37278a1e 192 */
ffe60014
DG
193int ust_consumer_ask_channel(struct ust_app_session *ua_sess,
194 struct ust_app_channel *ua_chan, struct consumer_output *consumer,
7972aab2 195 struct consumer_socket *socket, struct ust_registry_session *registry)
37278a1e
DG
196{
197 int ret;
37278a1e 198
ffe60014
DG
199 assert(ua_sess);
200 assert(ua_chan);
201 assert(consumer);
202 assert(socket);
203 assert(socket->fd >= 0);
7972aab2 204 assert(registry);
f50f23d9 205
ffe60014 206 pthread_mutex_lock(socket->lock);
37278a1e 207
7972aab2 208 ret = ask_channel_creation(ua_sess, ua_chan, consumer, socket, registry);
37278a1e
DG
209 if (ret < 0) {
210 goto error;
211 }
212
48842b30 213error:
ffe60014 214 pthread_mutex_unlock(socket->lock);
48842b30
DG
215 return ret;
216}
217
218/*
ffe60014
DG
219 * Send a get channel command to consumer using the given channel key. The
220 * channel object is populated and the stream list.
221 *
222 * Return 0 on success else a negative value.
48842b30 223 */
ffe60014
DG
224int ust_consumer_get_channel(struct consumer_socket *socket,
225 struct ust_app_channel *ua_chan)
48842b30 226{
ffe60014 227 int ret;
37278a1e 228 struct lttcomm_consumer_msg msg;
48842b30 229
ffe60014
DG
230 assert(ua_chan);
231 assert(socket);
232 assert(socket->fd >= 0);
48842b30 233
ffe60014
DG
234 msg.cmd_type = LTTNG_CONSUMER_GET_CHANNEL;
235 msg.u.get_channel.key = ua_chan->key;
37278a1e 236
ffe60014 237 pthread_mutex_lock(socket->lock);
840cb59c 238 health_code_update();
ca03de58 239
ffe60014
DG
240 /* Send command and wait for OK reply. */
241 ret = consumer_send_msg(socket, &msg);
37278a1e
DG
242 if (ret < 0) {
243 goto error;
244 }
245
ffe60014
DG
246 /* First, get the channel from consumer. */
247 ret = ustctl_recv_channel_from_consumer(socket->fd, &ua_chan->obj);
37278a1e 248 if (ret < 0) {
ffe60014
DG
249 if (ret != -EPIPE) {
250 ERR("Error recv channel from consumer %d with ret %d",
251 socket->fd, ret);
252 } else {
253 DBG3("UST app recv channel from consumer. Consumer is dead.");
254 }
37278a1e
DG
255 goto error;
256 }
00e2e675 257
ffe60014
DG
258 /* Next, get all streams. */
259 while (1) {
260 struct ust_app_stream *stream;
ca03de58 261
ffe60014
DG
262 /* Create UST stream */
263 stream = ust_app_alloc_stream();
264 if (stream == NULL) {
265 ret = -ENOMEM;
48842b30
DG
266 goto error;
267 }
268
ffe60014
DG
269 /* Stream object is populated by this call if successful. */
270 ret = ustctl_recv_stream_from_consumer(socket->fd, &stream->obj);
37278a1e 271 if (ret < 0) {
ffe60014
DG
272 free(stream);
273 if (ret == -LTTNG_UST_ERR_NOENT) {
274 DBG3("UST app consumer has no more stream available");
275 ret = 0;
276 break;
277 }
278 if (ret != -EPIPE) {
279 ERR("Recv stream from consumer %d with ret %d",
280 socket->fd, ret);
281 } else {
282 DBG3("UST app recv stream from consumer. Consumer is dead.");
00e2e675 283 }
48842b30
DG
284 goto error;
285 }
37278a1e 286
ffe60014
DG
287 /* Order is important this is why a list is used. */
288 cds_list_add_tail(&stream->list, &ua_chan->streams.head);
289 ua_chan->streams.count++;
37278a1e 290
ffe60014
DG
291 DBG2("UST app stream %d received succesfully", ua_chan->streams.count);
292 }
293
294 /* This MUST match or else we have a synchronization problem. */
295 assert(ua_chan->expected_stream_count == ua_chan->streams.count);
ca03de58 296
ffe60014
DG
297 /* Wait for confirmation that we can proceed with the streams. */
298 ret = consumer_recv_status_reply(socket);
37278a1e
DG
299 if (ret < 0) {
300 goto error;
301 }
302
303error:
ffe60014
DG
304 health_code_update();
305 pthread_mutex_unlock(socket->lock);
37278a1e
DG
306 return ret;
307}
308
309/*
ffe60014
DG
310 * Send a destroy channel command to consumer using the given channel key.
311 *
312 * Note that this command MUST be used prior to a successful
313 * LTTNG_CONSUMER_GET_CHANNEL because once this command is done successfully,
314 * the streams are dispatched to the consumer threads and MUST be teardown
315 * through the hang up process.
316 *
317 * Return 0 on success else a negative value.
37278a1e 318 */
ffe60014
DG
319int ust_consumer_destroy_channel(struct consumer_socket *socket,
320 struct ust_app_channel *ua_chan)
37278a1e 321{
ffe60014
DG
322 int ret;
323 struct lttcomm_consumer_msg msg;
a4b92340 324
ffe60014
DG
325 assert(ua_chan);
326 assert(socket);
327 assert(socket->fd >= 0);
37278a1e 328
ffe60014
DG
329 msg.cmd_type = LTTNG_CONSUMER_DESTROY_CHANNEL;
330 msg.u.destroy_channel.key = ua_chan->key;
173af62f 331
ffe60014
DG
332 pthread_mutex_lock(socket->lock);
333 health_code_update();
37278a1e 334
ffe60014 335 ret = consumer_send_msg(socket, &msg);
37278a1e
DG
336 if (ret < 0) {
337 goto error;
48842b30
DG
338 }
339
ffe60014
DG
340error:
341 health_code_update();
342 pthread_mutex_unlock(socket->lock);
343 return ret;
344}
aeb96892 345
ffe60014
DG
346/*
347 * Send a given stream to UST tracer.
348 *
349 * On success return 0 else a negative value.
350 */
351int ust_consumer_send_stream_to_ust(struct ust_app *app,
352 struct ust_app_channel *channel, struct ust_app_stream *stream)
353{
354 int ret;
355
356 assert(app);
357 assert(stream);
358 assert(channel);
359
360 DBG2("UST consumer send stream to app %d", app->sock);
361
362 /* Relay stream to application. */
363 ret = ustctl_send_stream_to_ust(app->sock, channel->obj, stream->obj);
364 if (ret < 0) {
365 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
366 ERR("Error ustctl send stream %s to app pid: %d with ret %d",
367 stream->name, app->pid, ret);
368 } else {
369 DBG3("UST app send stream to ust failed. Application is dead.");
48842b30 370 }
ffe60014 371 goto error;
48842b30 372 }
d0b96690 373 channel->handle = channel->obj->handle;
48842b30 374
ffe60014
DG
375error:
376 return ret;
377}
378
379/*
380 * Send channel previously received from the consumer to the UST tracer.
381 *
382 * On success return 0 else a negative value.
383 */
384int ust_consumer_send_channel_to_ust(struct ust_app *app,
385 struct ust_app_session *ua_sess, struct ust_app_channel *channel)
386{
387 int ret;
388
389 assert(app);
390 assert(ua_sess);
391 assert(channel);
392 assert(channel->obj);
393
7972aab2
DG
394 DBG2("UST app send channel to sock %d pid %d (name: %s, key: %" PRIu64 ")",
395 app->sock, app->pid, channel->name, channel->tracing_channel_id);
48842b30 396
ffe60014
DG
397 /* Send stream to application. */
398 ret = ustctl_send_channel_to_ust(app->sock, ua_sess->handle, channel->obj);
399 if (ret < 0) {
400 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
401 ERR("Error ustctl send channel %s to app pid: %d with ret %d",
402 channel->name, app->pid, ret);
403 } else {
404 DBG3("UST app send channel to ust failed. Application is dead.");
405 }
406 goto error;
407 }
48842b30
DG
408
409error:
410 return ret;
411}
331744e3
JD
412
413/*
414 * Handle the metadata requests from the UST consumer
415 *
416 * Return 0 on success else a negative value.
417 */
418int ust_consumer_metadata_request(struct consumer_socket *socket)
419{
420 int ret;
421 ssize_t ret_push;
422 struct lttcomm_metadata_request_msg request;
423 struct buffer_reg_uid *reg_uid;
424 struct ust_registry_session *ust_reg;
425 struct lttcomm_consumer_msg msg;
426
427 assert(socket);
428
429 rcu_read_lock();
430 pthread_mutex_lock(socket->lock);
431
432 health_code_update();
433
434 /* Wait for a metadata request */
435 ret = lttcomm_recv_unix_sock(socket->fd, &request, sizeof(request));
436 if (ret <= 0) {
437 ERR("Consumer closed the metadata socket");
438 ret = -1;
439 goto end;
440 }
441
442 DBG("Metadata request received for session %u, key %" PRIu64,
443 request.session_id, request.key);
444
445 reg_uid = buffer_reg_uid_find(request.session_id,
446 request.bits_per_long, request.uid);
447 if (reg_uid) {
448 ust_reg = reg_uid->registry->reg.ust;
449 } else {
450 struct buffer_reg_pid *reg_pid =
451 buffer_reg_pid_find(request.session_id);
452 if (!reg_pid) {
453 DBG("PID registry not found for session id %u",
454 request.session_id);
455
456 msg.cmd_type = LTTNG_ERR_UND;
457 (void) consumer_send_msg(socket, &msg);
458 /*
459 * This is possible since the session might have been destroyed
460 * during a consumer metadata request. So here, return gracefully
461 * because the destroy session will push the remaining metadata to
462 * the consumer.
463 */
464 ret = 0;
465 goto end;
466 }
467 ust_reg = reg_pid->registry->reg.ust;
468 }
469 assert(ust_reg);
470
471 ret_push = ust_app_push_metadata(ust_reg, socket, 1);
472 if (ret_push < 0) {
473 ERR("Pushing metadata");
474 ret = -1;
475 goto end;
476 }
477 DBG("UST Consumer metadata pushed successfully");
478 ret = 0;
479
480end:
481 pthread_mutex_unlock(socket->lock);
482 rcu_read_unlock();
483 return ret;
484}
This page took 0.053339 seconds and 4 git commands to generate.