Clean-up: explicit mb before decrementing lttng_sessiond_ready
[lttng-tools.git] / src / bin / lttng-sessiond / main.c
CommitLineData
826d496d
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1/*
2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
0fdd1e2c 3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
26296c48 4 * 2013 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
fac6795d 5 *
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AM
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License, version 2 only,
8 * as published by the Free Software Foundation.
91d76f53 9 *
d14d33bf
AM
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
91d76f53 14 *
d14d33bf
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15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
fac6795d
DG
18 */
19
6c1c0768 20#define _LGPL_SOURCE
fac6795d
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21#include <getopt.h>
22#include <grp.h>
23#include <limits.h>
0bb7724a 24#include <paths.h>
fac6795d
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25#include <pthread.h>
26#include <signal.h>
27#include <stdio.h>
28#include <stdlib.h>
29#include <string.h>
331744e3 30#include <inttypes.h>
0fdd1e2c 31#include <sys/mman.h>
b73401da 32#include <sys/mount.h>
1e307fab 33#include <sys/resource.h>
fac6795d
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34#include <sys/socket.h>
35#include <sys/stat.h>
36#include <sys/types.h>
0fdd1e2c 37#include <sys/wait.h>
5c827ce0 38#include <urcu/uatomic.h>
fac6795d 39#include <unistd.h>
4f0b90ee 40#include <ctype.h>
fac6795d 41
990570ed 42#include <common/common.h>
d27c42b8 43#include <common/compat/socket.h>
e8fa9fb0 44#include <common/compat/getenv.h>
db758600
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45#include <common/defaults.h>
46#include <common/kernel-consumer/kernel-consumer.h>
50c8f484 47#include <common/futex.h>
00e2e675 48#include <common/relayd/relayd.h>
81b86775 49#include <common/utils.h>
3ccdf997 50#include <common/daemonize.h>
f40ef1d5 51#include <common/config/session-config.h>
fac6795d 52
10a8a223 53#include "lttng-sessiond.h"
7972aab2 54#include "buffer-registry.h"
54d01ffb 55#include "channel.h"
2f77fc4b 56#include "cmd.h"
00e2e675 57#include "consumer.h"
099e26bd 58#include "context.h"
54d01ffb 59#include "event.h"
4771f025 60#include "kernel.h"
f1e16794 61#include "kernel-consumer.h"
096102bd 62#include "modprobe.h"
0fdd1e2c 63#include "shm.h"
1e307fab 64#include "ust-ctl.h"
00e2e675 65#include "ust-consumer.h"
8e68d1c8 66#include "utils.h"
4063050c 67#include "fd-limit.h"
8782cc74 68#include "health-sessiond.h"
8ac94142 69#include "testpoint.h"
d0b96690 70#include "ust-thread.h"
022d91ba 71#include "agent-thread.h"
fb198a11 72#include "save.h"
ef367a93 73#include "load-session-thread.h"
b3530820
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74#include "notification-thread.h"
75#include "notification-thread-commands.h"
db66e574 76#include "rotation-thread.h"
0dbc2034 77#include "lttng-syscall.h"
7c1d2758 78#include "agent.h"
5e97de00 79#include "ht-cleanup.h"
e6142f2e 80#include "sessiond-config.h"
d086f507 81#include "sessiond-timer.h"
ebaeda94 82
4fc83d94
PP
83static const char *help_msg =
84#ifdef LTTNG_EMBED_HELP
85#include <lttng-sessiond.8.h>
86#else
87NULL
88#endif
89;
90
fac6795d 91const char *progname;
1d4b027a 92static pid_t ppid; /* Parent PID for --sig-parent option */
0bb7724a 93static pid_t child_ppid; /* Internal parent PID use with daemonize. */
c9cb3e7d 94static int lockfile_fd = -1;
3bd1e081 95
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96/* Set to 1 when a SIGUSR1 signal is received. */
97static int recv_child_signal;
98
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99static struct lttng_kernel_tracer_version kernel_tracer_version;
100static struct lttng_kernel_tracer_abi_version kernel_tracer_abi_version;
101
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102/*
103 * Consumer daemon specific control data. Every value not initialized here is
104 * set to 0 by the static definition.
105 */
3bd1e081
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106static struct consumer_data kconsumer_data = {
107 .type = LTTNG_CONSUMER_KERNEL,
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108 .err_sock = -1,
109 .cmd_sock = -1,
b3530820 110 .channel_monitor_pipe = -1,
62c43103 111 .channel_rotate_pipe = -1,
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112 .pid_mutex = PTHREAD_MUTEX_INITIALIZER,
113 .lock = PTHREAD_MUTEX_INITIALIZER,
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114 .cond = PTHREAD_COND_INITIALIZER,
115 .cond_mutex = PTHREAD_MUTEX_INITIALIZER,
3bd1e081 116};
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117static struct consumer_data ustconsumer64_data = {
118 .type = LTTNG_CONSUMER64_UST,
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119 .err_sock = -1,
120 .cmd_sock = -1,
b3530820 121 .channel_monitor_pipe = -1,
62c43103 122 .channel_rotate_pipe = -1,
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123 .pid_mutex = PTHREAD_MUTEX_INITIALIZER,
124 .lock = PTHREAD_MUTEX_INITIALIZER,
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125 .cond = PTHREAD_COND_INITIALIZER,
126 .cond_mutex = PTHREAD_MUTEX_INITIALIZER,
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127};
128static struct consumer_data ustconsumer32_data = {
129 .type = LTTNG_CONSUMER32_UST,
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130 .err_sock = -1,
131 .cmd_sock = -1,
b3530820 132 .channel_monitor_pipe = -1,
62c43103 133 .channel_rotate_pipe = -1,
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134 .pid_mutex = PTHREAD_MUTEX_INITIALIZER,
135 .lock = PTHREAD_MUTEX_INITIALIZER,
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136 .cond = PTHREAD_COND_INITIALIZER,
137 .cond_mutex = PTHREAD_MUTEX_INITIALIZER,
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138};
139
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140/* Command line options */
141static const struct option long_options[] = {
0f5ea17c
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142 { "client-sock", required_argument, 0, 'c' },
143 { "apps-sock", required_argument, 0, 'a' },
144 { "kconsumerd-cmd-sock", required_argument, 0, '\0' },
145 { "kconsumerd-err-sock", required_argument, 0, '\0' },
146 { "ustconsumerd32-cmd-sock", required_argument, 0, '\0' },
147 { "ustconsumerd32-err-sock", required_argument, 0, '\0' },
148 { "ustconsumerd64-cmd-sock", required_argument, 0, '\0' },
149 { "ustconsumerd64-err-sock", required_argument, 0, '\0' },
150 { "consumerd32-path", required_argument, 0, '\0' },
151 { "consumerd32-libdir", required_argument, 0, '\0' },
152 { "consumerd64-path", required_argument, 0, '\0' },
153 { "consumerd64-libdir", required_argument, 0, '\0' },
154 { "daemonize", no_argument, 0, 'd' },
155 { "background", no_argument, 0, 'b' },
156 { "sig-parent", no_argument, 0, 'S' },
157 { "help", no_argument, 0, 'h' },
158 { "group", required_argument, 0, 'g' },
159 { "version", no_argument, 0, 'V' },
160 { "quiet", no_argument, 0, 'q' },
161 { "verbose", no_argument, 0, 'v' },
162 { "verbose-consumer", no_argument, 0, '\0' },
163 { "no-kernel", no_argument, 0, '\0' },
164 { "pidfile", required_argument, 0, 'p' },
165 { "agent-tcp-port", required_argument, 0, '\0' },
166 { "config", required_argument, 0, 'f' },
167 { "load", required_argument, 0, 'l' },
168 { "kmod-probes", required_argument, 0, '\0' },
169 { "extra-kmod-probes", required_argument, 0, '\0' },
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170 { NULL, 0, 0, 0 }
171};
172
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173struct sessiond_config config;
174
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175/* Command line options to ignore from configuration file */
176static const char *config_ignore_options[] = { "help", "version", "config" };
177
26c9d55e 178/* Shared between threads */
099e26bd 179static int dispatch_thread_exit;
fac6795d 180
1d4b027a 181/* Sockets and FDs */
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182static int client_sock = -1;
183static int apps_sock = -1;
2f77fc4b 184int kernel_tracer_fd = -1;
76d7553f 185static int kernel_poll_pipe[2] = { -1, -1 };
1d4b027a 186
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187/*
188 * Quit pipe for all threads. This permits a single cancellation point
189 * for all threads when receiving an event on the pipe.
190 */
76d7553f 191static int thread_quit_pipe[2] = { -1, -1 };
273ea72c 192
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193/*
194 * This pipe is used to inform the thread managing application communication
195 * that a command is queued and ready to be processed.
196 */
76d7553f 197static int apps_cmd_pipe[2] = { -1, -1 };
099e26bd 198
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199int apps_cmd_notify_pipe[2] = { -1, -1 };
200
1d4b027a 201/* Pthread, Mutexes and Semaphores */
1d4b027a 202static pthread_t apps_thread;
d0b96690 203static pthread_t apps_notify_thread;
099e26bd 204static pthread_t reg_apps_thread;
1d4b027a 205static pthread_t client_thread;
7a485870 206static pthread_t kernel_thread;
099e26bd 207static pthread_t dispatch_thread;
44a5e5eb 208static pthread_t health_thread;
0b2dc8df 209static pthread_t ht_cleanup_thread;
022d91ba 210static pthread_t agent_reg_thread;
ef367a93 211static pthread_t load_session_thread;
b3530820 212static pthread_t notification_thread;
db66e574 213static pthread_t rotation_thread;
d086f507 214static pthread_t timer_thread;
5eb91c98 215
099e26bd
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216/*
217 * UST registration command queue. This queue is tied with a futex and uses a N
218 * wakers / 1 waiter implemented and detailed in futex.c/.h
219 *
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220 * The thread_registration_apps and thread_dispatch_ust_registration uses this
221 * queue along with the wait/wake scheme. The thread_manage_apps receives down
222 * the line new application socket and monitors it for any I/O error or clean
223 * close that triggers an unregistration of the application.
099e26bd
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224 */
225static struct ust_cmd_queue ust_cmd_queue;
226
b5541356
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227/*
228 * Pointer initialized before thread creation.
229 *
230 * This points to the tracing session list containing the session count and a
231 * mutex lock. The lock MUST be taken if you iterate over the list. The lock
232 * MUST NOT be taken if you call a public function in session.c.
04ea676f 233 *
d063d709 234 * The lock is nested inside the structure: session_list_ptr->lock. Please use
54d01ffb 235 * session_lock_list and session_unlock_list for lock acquisition.
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236 */
237static struct ltt_session_list *session_list_ptr;
238
7753dea8
MD
239int ust_consumerd64_fd = -1;
240int ust_consumerd32_fd = -1;
241
2f77fc4b
DG
242static const char *module_proc_lttng = "/proc/lttng";
243
5c827ce0
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244/*
245 * Consumer daemon state which is changed when spawning it, killing it or in
246 * case of a fatal error.
247 */
248enum consumerd_state {
249 CONSUMER_STARTED = 1,
250 CONSUMER_STOPPED = 2,
251 CONSUMER_ERROR = 3,
252};
253
254/*
255 * This consumer daemon state is used to validate if a client command will be
256 * able to reach the consumer. If not, the client is informed. For instance,
257 * doing a "lttng start" when the consumer state is set to ERROR will return an
258 * error to the client.
259 *
260 * The following example shows a possible race condition of this scheme:
261 *
262 * consumer thread error happens
263 * client cmd arrives
264 * client cmd checks state -> still OK
265 * consumer thread exit, sets error
266 * client cmd try to talk to consumer
267 * ...
268 *
269 * However, since the consumer is a different daemon, we have no way of making
270 * sure the command will reach it safely even with this state flag. This is why
271 * we consider that up to the state validation during command processing, the
272 * command is safe. After that, we can not guarantee the correctness of the
273 * client request vis-a-vis the consumer.
274 */
275static enum consumerd_state ust_consumerd_state;
276static enum consumerd_state kernel_consumerd_state;
277
12744796
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278/* Set in main() with the current page size. */
279long page_size;
280
8782cc74
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281/* Application health monitoring */
282struct health_app *health_sessiond;
283
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284/* Am I root or not. */
285int is_root; /* Set to 1 if the daemon is running as root */
286
26296c48
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287const char * const config_section_name = "sessiond";
288
ef367a93
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289/* Load session thread information to operate. */
290struct load_session_thread_data *load_info;
291
b3530820
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292/* Notification thread handle. */
293struct notification_thread_handle *notification_thread_handle;
294
db66e574
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295/* Rotation thread handle. */
296struct rotation_thread_handle *rotation_thread_handle;
297
7c1d2758
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298/* Global hash tables */
299struct lttng_ht *agent_apps_ht_by_sock = NULL;
300
97bc1426 301/*
9cc1ba3b
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302 * The initialization of the session daemon is done in multiple phases.
303 *
304 * While all threads are launched near-simultaneously, only some of them
305 * are needed to ensure the session daemon can start to respond to client
b3530820 306 * requests.
9cc1ba3b
JG
307 *
308 * There are two important guarantees that we wish to offer with respect
309 * to the initialisation of the session daemon:
310 * - When the daemonize/background launcher process exits, the sessiond
311 * is fully able to respond to client requests,
312 * - Auto-loaded sessions are visible to clients.
313 *
314 * In order to achieve this, a number of support threads have to be launched
315 * to allow the "client" thread to function properly. Moreover, since the
316 * "load session" thread needs the client thread, we must provide a way
317 * for the "load session" thread to know that the "client" thread is up
318 * and running.
319 *
320 * Hence, the support threads decrement the lttng_sessiond_ready counter
321 * while the "client" threads waits for it to reach 0. Once the "client" thread
322 * unblocks, it posts the message_thread_ready semaphore which allows the
323 * "load session" thread to progress.
324 *
325 * This implies that the "load session" thread is the last to be initialized
326 * and will explicitly call sessiond_signal_parents(), which signals the parents
327 * that the session daemon is fully initialized.
328 *
329 * The four (4) support threads are:
330 * - agent_thread
331 * - notification_thread
332 * - rotation_thread
333 * - health_thread
97bc1426 334 */
bc4b3ff1
JG
335#define NR_LTTNG_SESSIOND_SUPPORT_THREADS 4
336int lttng_sessiond_ready = NR_LTTNG_SESSIOND_SUPPORT_THREADS;
97bc1426 337
5e97de00
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338int sessiond_check_thread_quit_pipe(int fd, uint32_t events)
339{
340 return (fd == thread_quit_pipe[0] && (events & LPOLLIN)) ? 1 : 0;
341}
342
97bc1426 343/* Notify parents that we are ready for cmd and health check */
ef367a93 344LTTNG_HIDDEN
9cc1ba3b 345void sessiond_signal_parents(void)
97bc1426 346{
9cc1ba3b
JG
347 /*
348 * Notify parent pid that we are ready to accept command
349 * for client side. This ppid is the one from the
350 * external process that spawned us.
351 */
352 if (config.sig_parent) {
353 kill(ppid, SIGUSR1);
354 }
97bc1426 355
9cc1ba3b
JG
356 /*
357 * Notify the parent of the fork() process that we are
358 * ready.
359 */
360 if (config.daemonize || config.background) {
361 kill(child_ppid, SIGUSR1);
97bc1426
MD
362 }
363}
364
9cc1ba3b
JG
365LTTNG_HIDDEN
366void sessiond_notify_ready(void)
367{
368 /*
524423d6
JG
369 * This memory barrier is paired with the one performed by
370 * the client thread after it has seen that 'lttng_sessiond_ready' is 0.
371 *
372 * The purpose of these memory barriers is to ensure that all
373 * initialization operations of the various threads that call this
374 * function to signal that they are ready are commited/published
375 * before the client thread can see the 'lttng_sessiond_ready' counter
376 * reach 0.
377 *
378 * Note that this could be a 'write' memory barrier, but a full barrier
379 * is used in case the code using this utility changes. The performance
380 * implications of this choice are minimal since this is a slow path.
9cc1ba3b 381 */
524423d6
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382 cmm_smp_mb();
383 uatomic_sub(&lttng_sessiond_ready, 1);
9cc1ba3b
JG
384}
385
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MD
386static
387int __sessiond_set_thread_pollset(struct lttng_poll_event *events, size_t size,
388 int *a_pipe)
5eb91c98
DG
389{
390 int ret;
391
d0b96690 392 assert(events);
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393
394 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
395 if (ret < 0) {
396 goto error;
397 }
398
399 /* Add quit pipe */
4a15001e 400 ret = lttng_poll_add(events, a_pipe[0], LPOLLIN | LPOLLERR);
5eb91c98
DG
401 if (ret < 0) {
402 goto error;
403 }
404
405 return 0;
406
407error:
408 return ret;
409}
410
4a15001e
MD
411/*
412 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
413 */
414int sessiond_set_thread_pollset(struct lttng_poll_event *events, size_t size)
415{
416 return __sessiond_set_thread_pollset(events, size, thread_quit_pipe);
417}
418
273ea72c 419/*
5eb91c98 420 * Init thread quit pipe.
273ea72c
DG
421 *
422 * Return -1 on error or 0 if all pipes are created.
423 */
4a15001e 424static int __init_thread_quit_pipe(int *a_pipe)
273ea72c 425{
730389d9 426 int ret, i;
273ea72c 427
4a15001e 428 ret = pipe(a_pipe);
273ea72c 429 if (ret < 0) {
730389d9 430 PERROR("thread quit pipe");
273ea72c
DG
431 goto error;
432 }
433
730389d9 434 for (i = 0; i < 2; i++) {
4a15001e 435 ret = fcntl(a_pipe[i], F_SETFD, FD_CLOEXEC);
730389d9
DG
436 if (ret < 0) {
437 PERROR("fcntl");
438 goto error;
439 }
440 }
441
273ea72c
DG
442error:
443 return ret;
444}
445
4a15001e
MD
446static int init_thread_quit_pipe(void)
447{
448 return __init_thread_quit_pipe(thread_quit_pipe);
449}
450
099e26bd
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451/*
452 * Stop all threads by closing the thread quit pipe.
453 */
cf3af59e
MD
454static void stop_threads(void)
455{
5eb91c98
DG
456 int ret;
457
cf3af59e
MD
458 /* Stopping all threads */
459 DBG("Terminating all threads");
54d01ffb 460 ret = notify_thread_pipe(thread_quit_pipe[1]);
5eb91c98
DG
461 if (ret < 0) {
462 ERR("write error on thread quit pipe");
463 }
464
099e26bd 465 /* Dispatch thread */
26c9d55e 466 CMM_STORE_SHARED(dispatch_thread_exit, 1);
099e26bd 467 futex_nto1_wake(&ust_cmd_queue.futex);
cf3af59e
MD
468}
469
e975f9f8
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470/*
471 * Close every consumer sockets.
472 */
473static void close_consumer_sockets(void)
474{
475 int ret;
476
477 if (kconsumer_data.err_sock >= 0) {
478 ret = close(kconsumer_data.err_sock);
479 if (ret < 0) {
480 PERROR("kernel consumer err_sock close");
481 }
482 }
483 if (ustconsumer32_data.err_sock >= 0) {
484 ret = close(ustconsumer32_data.err_sock);
485 if (ret < 0) {
a76cbd9f 486 PERROR("UST consumerd32 err_sock close");
e975f9f8
DG
487 }
488 }
489 if (ustconsumer64_data.err_sock >= 0) {
490 ret = close(ustconsumer64_data.err_sock);
491 if (ret < 0) {
a76cbd9f 492 PERROR("UST consumerd64 err_sock close");
e975f9f8
DG
493 }
494 }
495 if (kconsumer_data.cmd_sock >= 0) {
496 ret = close(kconsumer_data.cmd_sock);
497 if (ret < 0) {
498 PERROR("kernel consumer cmd_sock close");
499 }
500 }
501 if (ustconsumer32_data.cmd_sock >= 0) {
502 ret = close(ustconsumer32_data.cmd_sock);
503 if (ret < 0) {
a76cbd9f 504 PERROR("UST consumerd32 cmd_sock close");
e975f9f8
DG
505 }
506 }
507 if (ustconsumer64_data.cmd_sock >= 0) {
508 ret = close(ustconsumer64_data.cmd_sock);
509 if (ret < 0) {
a76cbd9f 510 PERROR("UST consumerd64 cmd_sock close");
e975f9f8
DG
511 }
512 }
b3530820
JG
513 if (kconsumer_data.channel_monitor_pipe >= 0) {
514 ret = close(kconsumer_data.channel_monitor_pipe);
515 if (ret < 0) {
516 PERROR("kernel consumer channel monitor pipe close");
517 }
518 }
519 if (ustconsumer32_data.channel_monitor_pipe >= 0) {
520 ret = close(ustconsumer32_data.channel_monitor_pipe);
521 if (ret < 0) {
522 PERROR("UST consumerd32 channel monitor pipe close");
523 }
524 }
525 if (ustconsumer64_data.channel_monitor_pipe >= 0) {
526 ret = close(ustconsumer64_data.channel_monitor_pipe);
527 if (ret < 0) {
528 PERROR("UST consumerd64 channel monitor pipe close");
529 }
530 }
62c43103
JD
531 if (kconsumer_data.channel_rotate_pipe >= 0) {
532 ret = close(kconsumer_data.channel_rotate_pipe);
533 if (ret < 0) {
534 PERROR("kernel consumer channel rotate pipe close");
535 }
536 }
537 if (ustconsumer32_data.channel_rotate_pipe >= 0) {
538 ret = close(ustconsumer32_data.channel_rotate_pipe);
539 if (ret < 0) {
540 PERROR("UST consumerd32 channel rotate pipe close");
541 }
542 }
543 if (ustconsumer64_data.channel_rotate_pipe >= 0) {
544 ret = close(ustconsumer64_data.channel_rotate_pipe);
545 if (ret < 0) {
546 PERROR("UST consumerd64 channel rotate pipe close");
547 }
548 }
e975f9f8
DG
549}
550
4e4714cb
JR
551/*
552 * Wait on consumer process termination.
553 *
554 * Need to be called with the consumer data lock held or from a context
555 * ensuring no concurrent access to data (e.g: cleanup).
556 */
557static void wait_consumer(struct consumer_data *consumer_data)
558{
559 pid_t ret;
560 int status;
561
562 if (consumer_data->pid <= 0) {
563 return;
564 }
565
566 DBG("Waiting for complete teardown of consumerd (PID: %d)",
567 consumer_data->pid);
568 ret = waitpid(consumer_data->pid, &status, 0);
569 if (ret == -1) {
570 PERROR("consumerd waitpid pid: %d", consumer_data->pid)
1640c24c 571 } else if (!WIFEXITED(status)) {
4e4714cb
JR
572 ERR("consumerd termination with error: %d",
573 WEXITSTATUS(ret));
574 }
575 consumer_data->pid = 0;
576}
577
fac6795d 578/*
4a15001e 579 * Cleanup the session daemon's data structures.
fac6795d 580 */
4a15001e 581static void sessiond_cleanup(void)
fac6795d 582{
ef599319 583 int ret;
af9737e9 584 struct ltt_session *sess, *stmp;
fac6795d 585
4a15001e 586 DBG("Cleanup sessiond");
e07ae692 587
4e449f3f
MD
588 /*
589 * Close the thread quit pipe. It has already done its job,
590 * since we are now called.
591 */
2f77fc4b
DG
592 utils_close_pipe(thread_quit_pipe);
593
35f90c40 594 /*
e6142f2e
JG
595 * If config.pid_file_path.value is undefined, the default file will be
596 * wiped when removing the rundir.
35f90c40 597 */
e6142f2e
JG
598 if (config.pid_file_path.value) {
599 ret = remove(config.pid_file_path.value);
35f90c40 600 if (ret < 0) {
e6142f2e 601 PERROR("remove pidfile %s", config.pid_file_path.value);
35f90c40
DG
602 }
603 }
604
e6142f2e
JG
605 DBG("Removing sessiond and consumerd content of directory %s",
606 config.rundir.value);
8c6c56c2
MD
607
608 /* sessiond */
e6142f2e
JG
609 DBG("Removing %s", config.pid_file_path.value);
610 (void) unlink(config.pid_file_path.value);
8c6c56c2 611
e6142f2e
JG
612 DBG("Removing %s", config.agent_port_file_path.value);
613 (void) unlink(config.agent_port_file_path.value);
cd9290dd 614
8c6c56c2 615 /* kconsumerd */
e6142f2e
JG
616 DBG("Removing %s", kconsumer_data.err_unix_sock_path);
617 (void) unlink(kconsumer_data.err_unix_sock_path);
618
619 DBG("Removing directory %s", config.kconsumerd_path.value);
620 (void) rmdir(config.kconsumerd_path.value);
8c6c56c2
MD
621
622 /* ust consumerd 32 */
e6142f2e
JG
623 DBG("Removing %s", config.consumerd32_err_unix_sock_path.value);
624 (void) unlink(config.consumerd32_err_unix_sock_path.value);
625
626 DBG("Removing directory %s", config.consumerd32_path.value);
627 (void) rmdir(config.consumerd32_path.value);
8c6c56c2
MD
628
629 /* ust consumerd 64 */
e6142f2e
JG
630 DBG("Removing %s", config.consumerd64_err_unix_sock_path.value);
631 (void) unlink(config.consumerd64_err_unix_sock_path.value);
632
633 DBG("Removing directory %s", config.consumerd64_path.value);
634 (void) rmdir(config.consumerd64_path.value);
5461b305 635
99bab54f 636 DBG("Cleaning up all sessions");
fac6795d 637
b5541356 638 /* Destroy session list mutex */
273ea72c
DG
639 if (session_list_ptr != NULL) {
640 pthread_mutex_destroy(&session_list_ptr->lock);
641
642 /* Cleanup ALL session */
54d01ffb
DG
643 cds_list_for_each_entry_safe(sess, stmp,
644 &session_list_ptr->head, list) {
90936dcf
JD
645 cmd_destroy_session(sess, kernel_poll_pipe[1],
646 notification_thread_handle);
273ea72c
DG
647 }
648 }
649
4e4714cb
JR
650 wait_consumer(&kconsumer_data);
651 wait_consumer(&ustconsumer64_data);
652 wait_consumer(&ustconsumer32_data);
653
6a4e4039
JG
654 DBG("Cleaning up all agent apps");
655 agent_app_ht_clean();
656
099e26bd 657 DBG("Closing all UST sockets");
56fff090 658 ust_app_clean_list();
7972aab2 659 buffer_reg_destroy_registries();
099e26bd 660
e6142f2e 661 if (is_root && !config.no_kernel) {
4fba7219 662 DBG2("Closing kernel fd");
a4b35e07 663 if (kernel_tracer_fd >= 0) {
76d7553f
MD
664 ret = close(kernel_tracer_fd);
665 if (ret) {
666 PERROR("close");
667 }
a4b35e07 668 }
2f50c8a3 669 DBG("Unloading kernel modules");
096102bd 670 modprobe_remove_lttng_all();
834978fd 671 free(syscall_table);
2f50c8a3 672 }
2f77fc4b 673
e975f9f8
DG
674 close_consumer_sockets();
675
ef367a93
JG
676 if (load_info) {
677 load_session_destroy_data(load_info);
678 free(load_info);
679 }
680
c9cb3e7d
JG
681 /*
682 * We do NOT rmdir rundir because there are other processes
683 * using it, for instance lttng-relayd, which can start in
684 * parallel with this teardown.
685 */
4a15001e
MD
686}
687
688/*
689 * Cleanup the daemon's option data structures.
690 */
691static void sessiond_cleanup_options(void)
692{
693 DBG("Cleaning up options");
694
e6142f2e 695 sessiond_config_fini(&config);
c9cb3e7d 696
7567352f 697 run_as_destroy_worker();
fac6795d
DG
698}
699
e065084a 700/*
d063d709 701 * Send data on a unix socket using the liblttsessiondcomm API.
e065084a 702 *
d063d709 703 * Return lttcomm error code.
e065084a
DG
704 */
705static int send_unix_sock(int sock, void *buf, size_t len)
706{
707 /* Check valid length */
c617c0c6 708 if (len == 0) {
e065084a
DG
709 return -1;
710 }
711
712 return lttcomm_send_unix_sock(sock, buf, len);
713}
714
5461b305 715/*
d063d709 716 * Free memory of a command context structure.
5461b305 717 */
a2fb29a5 718static void clean_command_ctx(struct command_ctx **cmd_ctx)
5461b305 719{
a2fb29a5
DG
720 DBG("Clean command context structure");
721 if (*cmd_ctx) {
722 if ((*cmd_ctx)->llm) {
723 free((*cmd_ctx)->llm);
5461b305 724 }
a2fb29a5
DG
725 if ((*cmd_ctx)->lsm) {
726 free((*cmd_ctx)->lsm);
5461b305 727 }
a2fb29a5
DG
728 free(*cmd_ctx);
729 *cmd_ctx = NULL;
5461b305
DG
730 }
731}
732
fac6795d 733/*
0fdd1e2c 734 * Notify UST applications using the shm mmap futex.
fac6795d 735 */
0fdd1e2c 736static int notify_ust_apps(int active)
fac6795d 737{
0fdd1e2c 738 char *wait_shm_mmap;
fac6795d 739
0fdd1e2c 740 DBG("Notifying applications of session daemon state: %d", active);
e07ae692 741
0fdd1e2c 742 /* See shm.c for this call implying mmap, shm and futex calls */
e6142f2e 743 wait_shm_mmap = shm_ust_get_mmap(config.wait_shm_path.value, is_root);
0fdd1e2c 744 if (wait_shm_mmap == NULL) {
fac6795d
DG
745 goto error;
746 }
747
0fdd1e2c
DG
748 /* Wake waiting process */
749 futex_wait_update((int32_t *) wait_shm_mmap, active);
750
751 /* Apps notified successfully */
752 return 0;
fac6795d
DG
753
754error:
0fdd1e2c 755 return -1;
fac6795d
DG
756}
757
e065084a 758/*
d063d709
DG
759 * Setup the outgoing data buffer for the response (llm) by allocating the
760 * right amount of memory and copying the original information from the lsm
761 * structure.
ca95a216 762 *
6e10c9b9 763 * Return 0 on success, negative value on error.
ca95a216 764 */
6e10c9b9
PP
765static int setup_lttng_msg(struct command_ctx *cmd_ctx,
766 const void *payload_buf, size_t payload_len,
767 const void *cmd_header_buf, size_t cmd_header_len)
ca95a216 768{
6e10c9b9
PP
769 int ret = 0;
770 const size_t header_len = sizeof(struct lttcomm_lttng_msg);
771 const size_t cmd_header_offset = header_len;
772 const size_t payload_offset = cmd_header_offset + cmd_header_len;
773 const size_t total_msg_size = header_len + cmd_header_len + payload_len;
ca95a216 774
6e10c9b9 775 cmd_ctx->llm = zmalloc(total_msg_size);
5461b305 776
5461b305 777 if (cmd_ctx->llm == NULL) {
76d7553f 778 PERROR("zmalloc");
5461b305 779 ret = -ENOMEM;
6e10c9b9 780 goto end;
ca95a216
DG
781 }
782
5461b305
DG
783 /* Copy common data */
784 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
9f19cc17 785 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
6e10c9b9
PP
786 cmd_ctx->llm->cmd_header_size = cmd_header_len;
787 cmd_ctx->llm->data_size = payload_len;
788 cmd_ctx->lttng_msg_size = total_msg_size;
5461b305 789
6e10c9b9 790 /* Copy command header */
b4e3ceb9
PP
791 if (cmd_header_len) {
792 memcpy(((uint8_t *) cmd_ctx->llm) + cmd_header_offset, cmd_header_buf,
793 cmd_header_len);
794 }
5461b305 795
6e10c9b9 796 /* Copy payload */
b4e3ceb9
PP
797 if (payload_len) {
798 memcpy(((uint8_t *) cmd_ctx->llm) + payload_offset, payload_buf,
799 payload_len);
800 }
ca95a216 801
6e10c9b9 802end:
ca95a216
DG
803 return ret;
804}
805
6e10c9b9
PP
806/*
807 * Version of setup_lttng_msg() without command header.
808 */
809static int setup_lttng_msg_no_cmd_header(struct command_ctx *cmd_ctx,
810 void *payload_buf, size_t payload_len)
811{
812 return setup_lttng_msg(cmd_ctx, payload_buf, payload_len, NULL, 0);
813}
7a485870 814/*
5eb91c98 815 * Update the kernel poll set of all channel fd available over all tracing
d063d709 816 * session. Add the wakeup pipe at the end of the set.
7a485870 817 */
5eb91c98 818static int update_kernel_poll(struct lttng_poll_event *events)
7a485870 819{
5eb91c98 820 int ret;
7a485870
DG
821 struct ltt_session *session;
822 struct ltt_kernel_channel *channel;
823
5eb91c98 824 DBG("Updating kernel poll set");
7a485870 825
54d01ffb 826 session_lock_list();
b5541356 827 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
54d01ffb 828 session_lock(session);
7a485870 829 if (session->kernel_session == NULL) {
54d01ffb 830 session_unlock(session);
7a485870
DG
831 continue;
832 }
7a485870 833
54d01ffb
DG
834 cds_list_for_each_entry(channel,
835 &session->kernel_session->channel_list.head, list) {
5eb91c98
DG
836 /* Add channel fd to the kernel poll set */
837 ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
838 if (ret < 0) {
54d01ffb 839 session_unlock(session);
5eb91c98
DG
840 goto error;
841 }
842 DBG("Channel fd %d added to kernel set", channel->fd);
7a485870 843 }
54d01ffb 844 session_unlock(session);
7a485870 845 }
54d01ffb 846 session_unlock_list();
7a485870 847
5eb91c98 848 return 0;
7a485870
DG
849
850error:
54d01ffb 851 session_unlock_list();
7a485870
DG
852 return -1;
853}
854
855/*
54d01ffb 856 * Find the channel fd from 'fd' over all tracing session. When found, check
d063d709 857 * for new channel stream and send those stream fds to the kernel consumer.
7a485870 858 *
d063d709 859 * Useful for CPU hotplug feature.
7a485870 860 */
2bdd86d4 861static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
7a485870
DG
862{
863 int ret = 0;
864 struct ltt_session *session;
173af62f 865 struct ltt_kernel_session *ksess;
7a485870
DG
866 struct ltt_kernel_channel *channel;
867
868 DBG("Updating kernel streams for channel fd %d", fd);
869
54d01ffb 870 session_lock_list();
b5541356 871 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
54d01ffb 872 session_lock(session);
7a485870 873 if (session->kernel_session == NULL) {
54d01ffb 874 session_unlock(session);
7a485870
DG
875 continue;
876 }
173af62f 877 ksess = session->kernel_session;
d9800920 878
4a15001e
MD
879 cds_list_for_each_entry(channel,
880 &ksess->channel_list.head, list) {
881 struct lttng_ht_iter iter;
882 struct consumer_socket *socket;
d9800920 883
4a15001e
MD
884 if (channel->fd != fd) {
885 continue;
886 }
887 DBG("Channel found, updating kernel streams");
888 ret = kernel_open_channel_stream(channel);
889 if (ret < 0) {
890 goto error;
891 }
892 /* Update the stream global counter */
893 ksess->stream_count_global += ret;
894
895 /*
896 * Have we already sent fds to the consumer? If yes, it
897 * means that tracing is started so it is safe to send
898 * our updated stream fds.
899 */
900 if (ksess->consumer_fds_sent != 1
901 || ksess->consumer == NULL) {
902 ret = -1;
903 goto error;
904 }
905
906 rcu_read_lock();
907 cds_lfht_for_each_entry(ksess->consumer->socks->ht,
908 &iter.iter, socket, node.node) {
909 pthread_mutex_lock(socket->lock);
1fc1b7c8 910 ret = kernel_consumer_send_channel_streams(socket,
4a15001e
MD
911 channel, ksess,
912 session->output_traces ? 1 : 0);
913 pthread_mutex_unlock(socket->lock);
914 if (ret < 0) {
e7fe706f 915 rcu_read_unlock();
4a15001e 916 goto error;
7a485870 917 }
7a485870 918 }
4a15001e 919 rcu_read_unlock();
7a485870 920 }
54d01ffb 921 session_unlock(session);
7a485870 922 }
54d01ffb 923 session_unlock_list();
b3c750d2 924 return ret;
7a485870 925
b3c750d2 926error:
54d01ffb
DG
927 session_unlock(session);
928 session_unlock_list();
7a485870
DG
929 return ret;
930}
931
487cf67c 932/*
ffe60014
DG
933 * For each tracing session, update newly registered apps. The session list
934 * lock MUST be acquired before calling this.
487cf67c
DG
935 */
936static void update_ust_app(int app_sock)
937{
938 struct ltt_session *sess, *stmp;
939
fdadac08
DG
940 /* Consumer is in an ERROR state. Stop any application update. */
941 if (uatomic_read(&ust_consumerd_state) == CONSUMER_ERROR) {
942 /* Stop the update process since the consumer is dead. */
943 return;
944 }
945
487cf67c
DG
946 /* For all tracing session(s) */
947 cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
a9ad0c8f
MD
948 struct ust_app *app;
949
4ee14516 950 session_lock(sess);
a9ad0c8f
MD
951 if (!sess->ust_session) {
952 goto unlock_session;
953 }
954
955 rcu_read_lock();
956 assert(app_sock >= 0);
957 app = ust_app_find_by_sock(app_sock);
958 if (app == NULL) {
959 /*
960 * Application can be unregistered before so
961 * this is possible hence simply stopping the
962 * update.
963 */
964 DBG3("UST app update failed to find app sock %d",
965 app_sock);
966 goto unlock_rcu;
421cb601 967 }
a9ad0c8f
MD
968 ust_app_global_update(sess->ust_session, app);
969 unlock_rcu:
970 rcu_read_unlock();
971 unlock_session:
4ee14516 972 session_unlock(sess);
487cf67c
DG
973 }
974}
975
7a485870 976/*
d063d709 977 * This thread manage event coming from the kernel.
7a485870 978 *
d063d709
DG
979 * Features supported in this thread:
980 * -) CPU Hotplug
7a485870
DG
981 */
982static void *thread_manage_kernel(void *data)
983{
139ac872 984 int ret, i, pollfd, update_poll_flag = 1, err = -1;
5eb91c98 985 uint32_t revents, nb_fd;
7a485870 986 char tmp;
5eb91c98 987 struct lttng_poll_event events;
7a485870 988
6993eeb3 989 DBG("[thread] Thread manage kernel started");
7a485870 990
6c71277b 991 health_register(health_sessiond, HEALTH_SESSIOND_TYPE_KERNEL);
927ca06a 992
d5d63bf1
DG
993 /*
994 * This first step of the while is to clean this structure which could free
6d737ce4 995 * non NULL pointers so initialize it before the loop.
d5d63bf1 996 */
6d737ce4 997 lttng_poll_init(&events);
d5d63bf1 998
e547b070 999 if (testpoint(sessiond_thread_manage_kernel)) {
6993eeb3
CB
1000 goto error_testpoint;
1001 }
8ac94142 1002
840cb59c 1003 health_code_update();
44a5e5eb 1004
e547b070 1005 if (testpoint(sessiond_thread_manage_kernel_before_loop)) {
d21b0d71 1006 goto error_testpoint;
6993eeb3
CB
1007 }
1008
7a485870 1009 while (1) {
840cb59c 1010 health_code_update();
44a5e5eb 1011
7a485870 1012 if (update_poll_flag == 1) {
d21b0d71
DG
1013 /* Clean events object. We are about to populate it again. */
1014 lttng_poll_clean(&events);
1015
d0b96690 1016 ret = sessiond_set_thread_pollset(&events, 2);
d21b0d71
DG
1017 if (ret < 0) {
1018 goto error_poll_create;
1019 }
1020
1021 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
1022 if (ret < 0) {
1023 goto error;
1024 }
5f822d0a 1025
d21b0d71 1026 /* This will add the available kernel channel if any. */
5eb91c98
DG
1027 ret = update_kernel_poll(&events);
1028 if (ret < 0) {
7a485870
DG
1029 goto error;
1030 }
1031 update_poll_flag = 0;
1032 }
1033
7fa2082e 1034 DBG("Thread kernel polling");
7a485870
DG
1035
1036 /* Poll infinite value of time */
88f2b785 1037 restart:
a78af745 1038 health_poll_entry();
5eb91c98 1039 ret = lttng_poll_wait(&events, -1);
7fa2082e
MD
1040 DBG("Thread kernel return from poll on %d fds",
1041 LTTNG_POLL_GETNB(&events));
a78af745 1042 health_poll_exit();
7a485870 1043 if (ret < 0) {
88f2b785
MD
1044 /*
1045 * Restart interrupted system call.
1046 */
1047 if (errno == EINTR) {
1048 goto restart;
1049 }
7a485870
DG
1050 goto error;
1051 } else if (ret == 0) {
1052 /* Should not happen since timeout is infinite */
85611738
DG
1053 ERR("Return value of poll is 0 with an infinite timeout.\n"
1054 "This should not have happened! Continuing...");
7a485870
DG
1055 continue;
1056 }
1057
0d9c5d77
DG
1058 nb_fd = ret;
1059
5eb91c98
DG
1060 for (i = 0; i < nb_fd; i++) {
1061 /* Fetch once the poll data */
1062 revents = LTTNG_POLL_GETEV(&events, i);
1063 pollfd = LTTNG_POLL_GETFD(&events, i);
7a485870 1064
840cb59c 1065 health_code_update();
44a5e5eb 1066
fd20dac9
MD
1067 if (!revents) {
1068 /* No activity for this FD (poll implementation). */
1069 continue;
1070 }
1071
5eb91c98 1072 /* Thread quit pipe has been closed. Killing thread. */
d0b96690 1073 ret = sessiond_check_thread_quit_pipe(pollfd, revents);
5eb91c98 1074 if (ret) {
139ac872
MD
1075 err = 0;
1076 goto exit;
5eb91c98 1077 }
7a485870 1078
5eb91c98 1079 /* Check for data on kernel pipe */
03e43155
MD
1080 if (revents & LPOLLIN) {
1081 if (pollfd == kernel_poll_pipe[0]) {
1082 (void) lttng_read(kernel_poll_pipe[0],
1083 &tmp, 1);
1084 /*
1085 * Ret value is useless here, if this pipe gets any actions an
1086 * update is required anyway.
1087 */
1088 update_poll_flag = 1;
1089 continue;
1090 } else {
1091 /*
1092 * New CPU detected by the kernel. Adding kernel stream to
1093 * kernel session and updating the kernel consumer
1094 */
2bdd86d4 1095 ret = update_kernel_stream(&kconsumer_data, pollfd);
5eb91c98
DG
1096 if (ret < 0) {
1097 continue;
1098 }
1099 break;
7a485870 1100 }
03e43155
MD
1101 } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1102 update_poll_flag = 1;
1103 continue;
1104 } else {
1105 ERR("Unexpected poll events %u for sock %d", revents, pollfd);
1106 goto error;
7a485870
DG
1107 }
1108 }
1109 }
1110
139ac872 1111exit:
7a485870 1112error:
5eb91c98 1113 lttng_poll_clean(&events);
76d7553f 1114error_poll_create:
6993eeb3 1115error_testpoint:
6620da75
DG
1116 utils_close_pipe(kernel_poll_pipe);
1117 kernel_poll_pipe[0] = kernel_poll_pipe[1] = -1;
139ac872 1118 if (err) {
840cb59c 1119 health_error();
139ac872 1120 ERR("Health error occurred in %s", __func__);
6620da75
DG
1121 WARN("Kernel thread died unexpectedly. "
1122 "Kernel tracing can continue but CPU hotplug is disabled.");
139ac872 1123 }
8782cc74 1124 health_unregister(health_sessiond);
76d7553f 1125 DBG("Kernel thread dying");
7a485870
DG
1126 return NULL;
1127}
1128
a23ec3a7
DG
1129/*
1130 * Signal pthread condition of the consumer data that the thread.
1131 */
1132static void signal_consumer_condition(struct consumer_data *data, int state)
1133{
1134 pthread_mutex_lock(&data->cond_mutex);
1135
1136 /*
1137 * The state is set before signaling. It can be any value, it's the waiter
1138 * job to correctly interpret this condition variable associated to the
1139 * consumer pthread_cond.
1140 *
1141 * A value of 0 means that the corresponding thread of the consumer data
1142 * was not started. 1 indicates that the thread has started and is ready
1143 * for action. A negative value means that there was an error during the
1144 * thread bootstrap.
1145 */
1146 data->consumer_thread_is_ready = state;
1147 (void) pthread_cond_signal(&data->cond);
1148
1149 pthread_mutex_unlock(&data->cond_mutex);
1150}
1151
1d4b027a 1152/*
3bd1e081 1153 * This thread manage the consumer error sent back to the session daemon.
1d4b027a 1154 */
3bd1e081 1155static void *thread_manage_consumer(void *data)
1d4b027a 1156{
42fc1d0b 1157 int sock = -1, i, ret, pollfd, err = -1, should_quit = 0;
5eb91c98 1158 uint32_t revents, nb_fd;
1d4b027a 1159 enum lttcomm_return_code code;
5eb91c98 1160 struct lttng_poll_event events;
3bd1e081 1161 struct consumer_data *consumer_data = data;
b3530820 1162 struct consumer_socket *cmd_socket_wrapper = NULL;
1d4b027a 1163
3bd1e081 1164 DBG("[thread] Manage consumer started");
1d4b027a 1165
34c1e15a
MD
1166 rcu_register_thread();
1167 rcu_thread_online();
1168
6c71277b 1169 health_register(health_sessiond, HEALTH_SESSIOND_TYPE_CONSUMER);
927ca06a 1170
855060f8 1171 health_code_update();
9449cc75 1172
5eb91c98 1173 /*
331744e3
JD
1174 * Pass 3 as size here for the thread quit pipe, consumerd_err_sock and the
1175 * metadata_sock. Nothing more will be added to this poll set.
5eb91c98 1176 */
331744e3 1177 ret = sessiond_set_thread_pollset(&events, 3);
5eb91c98 1178 if (ret < 0) {
76d7553f 1179 goto error_poll;
5eb91c98 1180 }
273ea72c 1181
edb8b045
DG
1182 /*
1183 * The error socket here is already in a listening state which was done
1184 * just before spawning this thread to avoid a race between the consumer
1185 * daemon exec trying to connect and the listen() call.
1186 */
3bd1e081 1187 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
5eb91c98
DG
1188 if (ret < 0) {
1189 goto error;
1190 }
1191
840cb59c 1192 health_code_update();
44a5e5eb 1193
331744e3 1194 /* Infinite blocking call, waiting for transmission */
88f2b785 1195restart:
a78af745 1196 health_poll_entry();
8ac94142 1197
e547b070 1198 if (testpoint(sessiond_thread_manage_consumer)) {
6993eeb3
CB
1199 goto error;
1200 }
8ac94142 1201
5eb91c98 1202 ret = lttng_poll_wait(&events, -1);
a78af745 1203 health_poll_exit();
273ea72c 1204 if (ret < 0) {
88f2b785
MD
1205 /*
1206 * Restart interrupted system call.
1207 */
1208 if (errno == EINTR) {
1209 goto restart;
1210 }
273ea72c
DG
1211 goto error;
1212 }
1213
0d9c5d77
DG
1214 nb_fd = ret;
1215
5eb91c98
DG
1216 for (i = 0; i < nb_fd; i++) {
1217 /* Fetch once the poll data */
1218 revents = LTTNG_POLL_GETEV(&events, i);
1219 pollfd = LTTNG_POLL_GETFD(&events, i);
1220
840cb59c 1221 health_code_update();
44a5e5eb 1222
fd20dac9
MD
1223 if (!revents) {
1224 /* No activity for this FD (poll implementation). */
1225 continue;
1226 }
1227
5eb91c98 1228 /* Thread quit pipe has been closed. Killing thread. */
d0b96690 1229 ret = sessiond_check_thread_quit_pipe(pollfd, revents);
5eb91c98 1230 if (ret) {
139ac872
MD
1231 err = 0;
1232 goto exit;
5eb91c98
DG
1233 }
1234
1235 /* Event on the registration socket */
3bd1e081 1236 if (pollfd == consumer_data->err_sock) {
03e43155
MD
1237 if (revents & LPOLLIN) {
1238 continue;
1239 } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
3bd1e081 1240 ERR("consumer err socket poll error");
5eb91c98 1241 goto error;
03e43155
MD
1242 } else {
1243 ERR("Unexpected poll events %u for sock %d", revents, pollfd);
1244 goto error;
5eb91c98
DG
1245 }
1246 }
273ea72c
DG
1247 }
1248
3bd1e081 1249 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
1d4b027a
DG
1250 if (sock < 0) {
1251 goto error;
1252 }
1253
b662582b
DG
1254 /*
1255 * Set the CLOEXEC flag. Return code is useless because either way, the
1256 * show must go on.
1257 */
1258 (void) utils_set_fd_cloexec(sock);
1259
840cb59c 1260 health_code_update();
44a5e5eb 1261
3bd1e081 1262 DBG2("Receiving code from consumer err_sock");
ee0b0061 1263
712ea556 1264 /* Getting status code from kconsumerd */
54d01ffb
DG
1265 ret = lttcomm_recv_unix_sock(sock, &code,
1266 sizeof(enum lttcomm_return_code));
1d4b027a
DG
1267 if (ret <= 0) {
1268 goto error;
1269 }
1270
840cb59c 1271 health_code_update();
b3530820 1272 if (code != LTTCOMM_CONSUMERD_COMMAND_SOCK_READY) {
3bd1e081 1273 ERR("consumer error when waiting for SOCK_READY : %s",
1d4b027a
DG
1274 lttcomm_get_readable_code(-code));
1275 goto error;
1276 }
1277
b3530820
JG
1278 /* Connect both command and metadata sockets. */
1279 consumer_data->cmd_sock =
1280 lttcomm_connect_unix_sock(
1281 consumer_data->cmd_unix_sock_path);
1282 consumer_data->metadata_fd =
1283 lttcomm_connect_unix_sock(
1284 consumer_data->cmd_unix_sock_path);
1285 if (consumer_data->cmd_sock < 0 || consumer_data->metadata_fd < 0) {
1286 PERROR("consumer connect cmd socket");
1287 /* On error, signal condition and quit. */
1288 signal_consumer_condition(consumer_data, -1);
1289 goto error;
1290 }
1291
1292 consumer_data->metadata_sock.fd_ptr = &consumer_data->metadata_fd;
1293
1294 /* Create metadata socket lock. */
1295 consumer_data->metadata_sock.lock = zmalloc(sizeof(pthread_mutex_t));
1296 if (consumer_data->metadata_sock.lock == NULL) {
1297 PERROR("zmalloc pthread mutex");
1298 goto error;
1299 }
1300 pthread_mutex_init(consumer_data->metadata_sock.lock, NULL);
1301
1302 DBG("Consumer command socket ready (fd: %d", consumer_data->cmd_sock);
1303 DBG("Consumer metadata socket ready (fd: %d)",
1304 consumer_data->metadata_fd);
1305
1306 /*
1307 * Remove the consumerd error sock since we've established a connection.
1308 */
3bd1e081 1309 ret = lttng_poll_del(&events, consumer_data->err_sock);
72079cae 1310 if (ret < 0) {
72079cae
DG
1311 goto error;
1312 }
1313
331744e3 1314 /* Add new accepted error socket. */
5eb91c98
DG
1315 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
1316 if (ret < 0) {
72079cae 1317 goto error;
5eb91c98
DG
1318 }
1319
331744e3 1320 /* Add metadata socket that is successfully connected. */
4ce514c4 1321 ret = lttng_poll_add(&events, consumer_data->metadata_fd,
331744e3
JD
1322 LPOLLIN | LPOLLRDHUP);
1323 if (ret < 0) {
1324 goto error;
1325 }
1326
840cb59c 1327 health_code_update();
44a5e5eb 1328
b3530820 1329 /*
62c43103
JD
1330 * Transfer the write-end of the channel monitoring and rotate pipe
1331 * to the consumer by issuing a SET_CHANNEL_MONITOR_PIPE and
1332 * SET_CHANNEL_ROTATE_PIPE commands.
b3530820
JG
1333 */
1334 cmd_socket_wrapper = consumer_allocate_socket(&consumer_data->cmd_sock);
1335 if (!cmd_socket_wrapper) {
1336 goto error;
1337 }
3e4dc117 1338 cmd_socket_wrapper->lock = &consumer_data->lock;
b3530820
JG
1339
1340 ret = consumer_send_channel_monitor_pipe(cmd_socket_wrapper,
1341 consumer_data->channel_monitor_pipe);
1342 if (ret) {
1343 goto error;
1344 }
62c43103
JD
1345
1346 ret = consumer_send_channel_rotate_pipe(cmd_socket_wrapper,
1347 consumer_data->channel_rotate_pipe);
1348 if (ret) {
1349 goto error;
1350 }
1351
b3530820
JG
1352 /* Discard the socket wrapper as it is no longer needed. */
1353 consumer_destroy_socket(cmd_socket_wrapper);
1354 cmd_socket_wrapper = NULL;
1355
1356 /* The thread is completely initialized, signal that it is ready. */
1357 signal_consumer_condition(consumer_data, 1);
1358
331744e3 1359 /* Infinite blocking call, waiting for transmission */
88f2b785 1360restart_poll:
331744e3 1361 while (1) {
42fc1d0b
DG
1362 health_code_update();
1363
1364 /* Exit the thread because the thread quit pipe has been triggered. */
1365 if (should_quit) {
1366 /* Not a health error. */
1367 err = 0;
1368 goto exit;
1369 }
1370
331744e3
JD
1371 health_poll_entry();
1372 ret = lttng_poll_wait(&events, -1);
1373 health_poll_exit();
1374 if (ret < 0) {
1375 /*
1376 * Restart interrupted system call.
1377 */
1378 if (errno == EINTR) {
1379 goto restart_poll;
1380 }
1381 goto error;
88f2b785 1382 }
72079cae 1383
331744e3 1384 nb_fd = ret;
0d9c5d77 1385
331744e3
JD
1386 for (i = 0; i < nb_fd; i++) {
1387 /* Fetch once the poll data */
1388 revents = LTTNG_POLL_GETEV(&events, i);
1389 pollfd = LTTNG_POLL_GETFD(&events, i);
5eb91c98 1390
331744e3 1391 health_code_update();
44a5e5eb 1392
fd20dac9
MD
1393 if (!revents) {
1394 /* No activity for this FD (poll implementation). */
1395 continue;
1396 }
1397
42fc1d0b
DG
1398 /*
1399 * Thread quit pipe has been triggered, flag that we should stop
1400 * but continue the current loop to handle potential data from
1401 * consumer.
1402 */
1403 should_quit = sessiond_check_thread_quit_pipe(pollfd, revents);
5eb91c98 1404
331744e3
JD
1405 if (pollfd == sock) {
1406 /* Event on the consumerd socket */
03e43155
MD
1407 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)
1408 && !(revents & LPOLLIN)) {
331744e3
JD
1409 ERR("consumer err socket second poll error");
1410 goto error;
1411 }
1412 health_code_update();
1413 /* Wait for any kconsumerd error */
1414 ret = lttcomm_recv_unix_sock(sock, &code,
1415 sizeof(enum lttcomm_return_code));
1416 if (ret <= 0) {
1417 ERR("consumer closed the command socket");
1418 goto error;
1419 }
1420
1421 ERR("consumer return code : %s",
1422 lttcomm_get_readable_code(-code));
1423
1424 goto exit;
4ce514c4 1425 } else if (pollfd == consumer_data->metadata_fd) {
03e43155
MD
1426 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)
1427 && !(revents & LPOLLIN)) {
1428 ERR("consumer err metadata socket second poll error");
1429 goto error;
1430 }
331744e3
JD
1431 /* UST metadata requests */
1432 ret = ust_consumer_metadata_request(
1433 &consumer_data->metadata_sock);
1434 if (ret < 0) {
1435 ERR("Handling metadata request");
1436 goto error;
1437 }
5eb91c98 1438 }
42fc1d0b 1439 /* No need for an else branch all FDs are tested prior. */
5eb91c98 1440 }
331744e3 1441 health_code_update();
5eb91c98
DG
1442 }
1443
139ac872 1444exit:
1d4b027a 1445error:
fdadac08
DG
1446 /*
1447 * We lock here because we are about to close the sockets and some other
92db7cdc
DG
1448 * thread might be using them so get exclusive access which will abort all
1449 * other consumer command by other threads.
fdadac08
DG
1450 */
1451 pthread_mutex_lock(&consumer_data->lock);
1452
5c827ce0
DG
1453 /* Immediately set the consumerd state to stopped */
1454 if (consumer_data->type == LTTNG_CONSUMER_KERNEL) {
1455 uatomic_set(&kernel_consumerd_state, CONSUMER_ERROR);
1456 } else if (consumer_data->type == LTTNG_CONSUMER64_UST ||
1457 consumer_data->type == LTTNG_CONSUMER32_UST) {
1458 uatomic_set(&ust_consumerd_state, CONSUMER_ERROR);
1459 } else {
1460 /* Code flow error... */
1461 assert(0);
1462 }
1463
76d7553f
MD
1464 if (consumer_data->err_sock >= 0) {
1465 ret = close(consumer_data->err_sock);
1466 if (ret) {
1467 PERROR("close");
1468 }
a76cbd9f 1469 consumer_data->err_sock = -1;
76d7553f
MD
1470 }
1471 if (consumer_data->cmd_sock >= 0) {
1472 ret = close(consumer_data->cmd_sock);
1473 if (ret) {
1474 PERROR("close");
1475 }
a76cbd9f 1476 consumer_data->cmd_sock = -1;
76d7553f 1477 }
96544455
SS
1478 if (consumer_data->metadata_sock.fd_ptr &&
1479 *consumer_data->metadata_sock.fd_ptr >= 0) {
9363801e 1480 ret = close(*consumer_data->metadata_sock.fd_ptr);
331744e3
JD
1481 if (ret) {
1482 PERROR("close");
1483 }
1484 }
76d7553f
MD
1485 if (sock >= 0) {
1486 ret = close(sock);
1487 if (ret) {
1488 PERROR("close");
1489 }
1490 }
273ea72c 1491
3bd1e081
MD
1492 unlink(consumer_data->err_unix_sock_path);
1493 unlink(consumer_data->cmd_unix_sock_path);
fdadac08 1494 pthread_mutex_unlock(&consumer_data->lock);
92db7cdc 1495
fdadac08 1496 /* Cleanup metadata socket mutex. */
96544455
SS
1497 if (consumer_data->metadata_sock.lock) {
1498 pthread_mutex_destroy(consumer_data->metadata_sock.lock);
1499 free(consumer_data->metadata_sock.lock);
1500 }
5eb91c98 1501 lttng_poll_clean(&events);
b3530820
JG
1502
1503 if (cmd_socket_wrapper) {
1504 consumer_destroy_socket(cmd_socket_wrapper);
1505 }
76d7553f 1506error_poll:
139ac872 1507 if (err) {
840cb59c 1508 health_error();
139ac872
MD
1509 ERR("Health error occurred in %s", __func__);
1510 }
8782cc74 1511 health_unregister(health_sessiond);
76d7553f 1512 DBG("consumer thread cleanup completed");
0177d773 1513
34c1e15a
MD
1514 rcu_thread_offline();
1515 rcu_unregister_thread();
1516
5eb91c98 1517 return NULL;
099e26bd
DG
1518}
1519
099e26bd 1520/*
81f04d5f
JG
1521 * This thread receives application command sockets (FDs) on the
1522 * apps_cmd_pipe and waits (polls) on them until they are closed
1523 * or an error occurs.
1524 *
1525 * At that point, it flushes the data (tracing and metadata) associated
1526 * with this application and tears down ust app sessions and other
1527 * associated data structures through ust_app_unregister().
1528 *
1529 * Note that this thread never sends commands to the applications
1530 * through the command sockets; it merely listens for hang-ups
1531 * and errors on those sockets and cleans-up as they occur.
1d4b027a
DG
1532 */
1533static void *thread_manage_apps(void *data)
099e26bd 1534{
139ac872 1535 int i, ret, pollfd, err = -1;
6cd525e8 1536 ssize_t size_ret;
5eb91c98 1537 uint32_t revents, nb_fd;
5eb91c98 1538 struct lttng_poll_event events;
099e26bd
DG
1539
1540 DBG("[thread] Manage application started");
1541
f6a9efaa
DG
1542 rcu_register_thread();
1543 rcu_thread_online();
1544
6c71277b 1545 health_register(health_sessiond, HEALTH_SESSIOND_TYPE_APP_MANAGE);
927ca06a 1546
e547b070 1547 if (testpoint(sessiond_thread_manage_apps)) {
6993eeb3
CB
1548 goto error_testpoint;
1549 }
1550
840cb59c 1551 health_code_update();
44a5e5eb 1552
d0b96690 1553 ret = sessiond_set_thread_pollset(&events, 2);
5eb91c98 1554 if (ret < 0) {
76d7553f 1555 goto error_poll_create;
5eb91c98 1556 }
099e26bd 1557
5eb91c98
DG
1558 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1559 if (ret < 0) {
1560 goto error;
1561 }
099e26bd 1562
e547b070 1563 if (testpoint(sessiond_thread_manage_apps_before_loop)) {
6993eeb3
CB
1564 goto error;
1565 }
8ac94142 1566
840cb59c 1567 health_code_update();
44a5e5eb 1568
5eb91c98 1569 while (1) {
7fa2082e 1570 DBG("Apps thread polling");
099e26bd
DG
1571
1572 /* Inifinite blocking call, waiting for transmission */
88f2b785 1573 restart:
a78af745 1574 health_poll_entry();
5eb91c98 1575 ret = lttng_poll_wait(&events, -1);
7fa2082e
MD
1576 DBG("Apps thread return from poll on %d fds",
1577 LTTNG_POLL_GETNB(&events));
a78af745 1578 health_poll_exit();
099e26bd 1579 if (ret < 0) {
88f2b785
MD
1580 /*
1581 * Restart interrupted system call.
1582 */
1583 if (errno == EINTR) {
1584 goto restart;
1585 }
099e26bd
DG
1586 goto error;
1587 }
1588
0d9c5d77
DG
1589 nb_fd = ret;
1590
5eb91c98
DG
1591 for (i = 0; i < nb_fd; i++) {
1592 /* Fetch once the poll data */
1593 revents = LTTNG_POLL_GETEV(&events, i);
1594 pollfd = LTTNG_POLL_GETFD(&events, i);
1595
840cb59c 1596 health_code_update();
44a5e5eb 1597
fd20dac9
MD
1598 if (!revents) {
1599 /* No activity for this FD (poll implementation). */
1600 continue;
1601 }
1602
5eb91c98 1603 /* Thread quit pipe has been closed. Killing thread. */
d0b96690 1604 ret = sessiond_check_thread_quit_pipe(pollfd, revents);
5eb91c98 1605 if (ret) {
139ac872
MD
1606 err = 0;
1607 goto exit;
5eb91c98 1608 }
099e26bd 1609
5eb91c98
DG
1610 /* Inspect the apps cmd pipe */
1611 if (pollfd == apps_cmd_pipe[0]) {
03e43155 1612 if (revents & LPOLLIN) {
d0b96690
DG
1613 int sock;
1614
5eb91c98 1615 /* Empty pipe */
6cd525e8
MD
1616 size_ret = lttng_read(apps_cmd_pipe[0], &sock, sizeof(sock));
1617 if (size_ret < sizeof(sock)) {
76d7553f 1618 PERROR("read apps cmd pipe");
5eb91c98
DG
1619 goto error;
1620 }
099e26bd 1621
840cb59c 1622 health_code_update();
44a5e5eb 1623
ffe60014 1624 /*
03e43155
MD
1625 * Since this is a command socket (write then read),
1626 * we only monitor the error events of the socket.
ffe60014 1627 */
d0b96690
DG
1628 ret = lttng_poll_add(&events, sock,
1629 LPOLLERR | LPOLLHUP | LPOLLRDHUP);
1630 if (ret < 0) {
5eb91c98 1631 goto error;
e0c7ec2b 1632 }
acc7b41b 1633
d0b96690 1634 DBG("Apps with sock %d added to poll set", sock);
03e43155
MD
1635 } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1636 ERR("Apps command pipe error");
1637 goto error;
1638 } else {
1639 ERR("Unknown poll events %u for sock %d", revents, pollfd);
1640 goto error;
0177d773 1641 }
5eb91c98
DG
1642 } else {
1643 /*
54d01ffb
DG
1644 * At this point, we know that a registered application made
1645 * the event at poll_wait.
5eb91c98
DG
1646 */
1647 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1648 /* Removing from the poll set */
1649 ret = lttng_poll_del(&events, pollfd);
1650 if (ret < 0) {
1651 goto error;
1652 }
099e26bd 1653
b9d9b220 1654 /* Socket closed on remote end. */
56fff090 1655 ust_app_unregister(pollfd);
03e43155
MD
1656 } else {
1657 ERR("Unexpected poll events %u for sock %d", revents, pollfd);
1658 goto error;
5eb91c98 1659 }
099e26bd 1660 }
44a5e5eb 1661
840cb59c 1662 health_code_update();
099e26bd 1663 }
099e26bd
DG
1664 }
1665
139ac872 1666exit:
099e26bd 1667error:
5eb91c98 1668 lttng_poll_clean(&events);
76d7553f 1669error_poll_create:
6993eeb3 1670error_testpoint:
6620da75
DG
1671 utils_close_pipe(apps_cmd_pipe);
1672 apps_cmd_pipe[0] = apps_cmd_pipe[1] = -1;
1673
1674 /*
1675 * We don't clean the UST app hash table here since already registered
1676 * applications can still be controlled so let them be until the session
1677 * daemon dies or the applications stop.
1678 */
1679
139ac872 1680 if (err) {
840cb59c 1681 health_error();
139ac872
MD
1682 ERR("Health error occurred in %s", __func__);
1683 }
8782cc74 1684 health_unregister(health_sessiond);
76d7553f 1685 DBG("Application communication apps thread cleanup complete");
f6a9efaa
DG
1686 rcu_thread_offline();
1687 rcu_unregister_thread();
099e26bd
DG
1688 return NULL;
1689}
1690
d0b96690 1691/*
d88aee68
DG
1692 * Send a socket to a thread This is called from the dispatch UST registration
1693 * thread once all sockets are set for the application.
d0b96690 1694 *
b85dc84c
DG
1695 * The sock value can be invalid, we don't really care, the thread will handle
1696 * it and make the necessary cleanup if so.
1697 *
d0b96690
DG
1698 * On success, return 0 else a negative value being the errno message of the
1699 * write().
1700 */
d88aee68 1701static int send_socket_to_thread(int fd, int sock)
d0b96690 1702{
6cd525e8 1703 ssize_t ret;
d0b96690 1704
b85dc84c
DG
1705 /*
1706 * It's possible that the FD is set as invalid with -1 concurrently just
1707 * before calling this function being a shutdown state of the thread.
1708 */
1709 if (fd < 0) {
1710 ret = -EBADF;
1711 goto error;
1712 }
d0b96690 1713
6cd525e8
MD
1714 ret = lttng_write(fd, &sock, sizeof(sock));
1715 if (ret < sizeof(sock)) {
d88aee68 1716 PERROR("write apps pipe %d", fd);
d0b96690
DG
1717 if (ret < 0) {
1718 ret = -errno;
1719 }
1720 goto error;
1721 }
1722
1723 /* All good. Don't send back the write positive ret value. */
1724 ret = 0;
1725error:
6cd525e8 1726 return (int) ret;
d0b96690
DG
1727}
1728
f45e313d
DG
1729/*
1730 * Sanitize the wait queue of the dispatch registration thread meaning removing
1731 * invalid nodes from it. This is to avoid memory leaks for the case the UST
1732 * notify socket is never received.
1733 */
1734static void sanitize_wait_queue(struct ust_reg_wait_queue *wait_queue)
1735{
1736 int ret, nb_fd = 0, i;
1737 unsigned int fd_added = 0;
1738 struct lttng_poll_event events;
1739 struct ust_reg_wait_node *wait_node = NULL, *tmp_wait_node;
1740
1741 assert(wait_queue);
1742
1743 lttng_poll_init(&events);
1744
1745 /* Just skip everything for an empty queue. */
1746 if (!wait_queue->count) {
1747 goto end;
1748 }
1749
1750 ret = lttng_poll_create(&events, wait_queue->count, LTTNG_CLOEXEC);
1751 if (ret < 0) {
1752 goto error_create;
1753 }
1754
1755 cds_list_for_each_entry_safe(wait_node, tmp_wait_node,
1756 &wait_queue->head, head) {
1757 assert(wait_node->app);
1758 ret = lttng_poll_add(&events, wait_node->app->sock,
1759 LPOLLHUP | LPOLLERR);
1760 if (ret < 0) {
1761 goto error;
1762 }
1763
1764 fd_added = 1;
1765 }
1766
1767 if (!fd_added) {
1768 goto end;
1769 }
1770
1771 /*
1772 * Poll but don't block so we can quickly identify the faulty events and
1773 * clean them afterwards from the wait queue.
1774 */
1775 ret = lttng_poll_wait(&events, 0);
1776 if (ret < 0) {
1777 goto error;
1778 }
1779 nb_fd = ret;
1780
1781 for (i = 0; i < nb_fd; i++) {
1782 /* Get faulty FD. */
1783 uint32_t revents = LTTNG_POLL_GETEV(&events, i);
1784 int pollfd = LTTNG_POLL_GETFD(&events, i);
1785
fd20dac9
MD
1786 if (!revents) {
1787 /* No activity for this FD (poll implementation). */
1788 continue;
1789 }
1790
f45e313d
DG
1791 cds_list_for_each_entry_safe(wait_node, tmp_wait_node,
1792 &wait_queue->head, head) {
1793 if (pollfd == wait_node->app->sock &&
1794 (revents & (LPOLLHUP | LPOLLERR))) {
1795 cds_list_del(&wait_node->head);
1796 wait_queue->count--;
1797 ust_app_destroy(wait_node->app);
1798 free(wait_node);
48b40bcf
JG
1799 /*
1800 * Silence warning of use-after-free in
1801 * cds_list_for_each_entry_safe which uses
1802 * __typeof__(*wait_node).
1803 */
1804 wait_node = NULL;
f45e313d 1805 break;
03e43155
MD
1806 } else {
1807 ERR("Unexpected poll events %u for sock %d", revents, pollfd);
1808 goto error;
f45e313d
DG
1809 }
1810 }
1811 }
1812
1813 if (nb_fd > 0) {
1814 DBG("Wait queue sanitized, %d node were cleaned up", nb_fd);
1815 }
1816
1817end:
1818 lttng_poll_clean(&events);
1819 return;
1820
1821error:
1822 lttng_poll_clean(&events);
1823error_create:
1824 ERR("Unable to sanitize wait queue");
1825 return;
1826}
1827
099e26bd
DG
1828/*
1829 * Dispatch request from the registration threads to the application
1830 * communication thread.
1831 */
1832static void *thread_dispatch_ust_registration(void *data)
1833{
12e2b881 1834 int ret, err = -1;
8bdee6e2 1835 struct cds_wfcq_node *node;
099e26bd 1836 struct ust_command *ust_cmd = NULL;
f45e313d
DG
1837 struct ust_reg_wait_node *wait_node = NULL, *tmp_wait_node;
1838 struct ust_reg_wait_queue wait_queue = {
1839 .count = 0,
1840 };
d0b96690 1841
967e3668
MD
1842 rcu_register_thread();
1843
6c71277b 1844 health_register(health_sessiond, HEALTH_SESSIOND_TYPE_APP_REG_DISPATCH);
12e2b881 1845
9ad42ec1
MD
1846 if (testpoint(sessiond_thread_app_reg_dispatch)) {
1847 goto error_testpoint;
1848 }
1849
12e2b881
MD
1850 health_code_update();
1851
f45e313d 1852 CDS_INIT_LIST_HEAD(&wait_queue.head);
099e26bd
DG
1853
1854 DBG("[thread] Dispatch UST command started");
1855
0ed3b1a8 1856 for (;;) {
12e2b881
MD
1857 health_code_update();
1858
099e26bd
DG
1859 /* Atomically prepare the queue futex */
1860 futex_nto1_prepare(&ust_cmd_queue.futex);
1861
0ed3b1a8
MD
1862 if (CMM_LOAD_SHARED(dispatch_thread_exit)) {
1863 break;
1864 }
1865
099e26bd 1866 do {
d0b96690 1867 struct ust_app *app = NULL;
7972aab2 1868 ust_cmd = NULL;
d0b96690 1869
f45e313d
DG
1870 /*
1871 * Make sure we don't have node(s) that have hung up before receiving
1872 * the notify socket. This is to clean the list in order to avoid
1873 * memory leaks from notify socket that are never seen.
1874 */
1875 sanitize_wait_queue(&wait_queue);
1876
12e2b881 1877 health_code_update();
099e26bd 1878 /* Dequeue command for registration */
8bdee6e2 1879 node = cds_wfcq_dequeue_blocking(&ust_cmd_queue.head, &ust_cmd_queue.tail);
099e26bd 1880 if (node == NULL) {
00a17c97 1881 DBG("Woken up but nothing in the UST command queue");
099e26bd
DG
1882 /* Continue thread execution */
1883 break;
1884 }
1885
1886 ust_cmd = caa_container_of(node, struct ust_command, node);
1887
2f50c8a3
DG
1888 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1889 " gid:%d sock:%d name:%s (version %d.%d)",
1890 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1891 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1892 ust_cmd->sock, ust_cmd->reg_msg.name,
1893 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
d0b96690
DG
1894
1895 if (ust_cmd->reg_msg.type == USTCTL_SOCKET_CMD) {
1896 wait_node = zmalloc(sizeof(*wait_node));
1897 if (!wait_node) {
1898 PERROR("zmalloc wait_node dispatch");
020d7f60
DG
1899 ret = close(ust_cmd->sock);
1900 if (ret < 0) {
1901 PERROR("close ust sock dispatch %d", ust_cmd->sock);
1902 }
51dec90d 1903 lttng_fd_put(LTTNG_FD_APPS, 1);
7972aab2 1904 free(ust_cmd);
d0b96690
DG
1905 goto error;
1906 }
1907 CDS_INIT_LIST_HEAD(&wait_node->head);
1908
1909 /* Create application object if socket is CMD. */
1910 wait_node->app = ust_app_create(&ust_cmd->reg_msg,
1911 ust_cmd->sock);
1912 if (!wait_node->app) {
1913 ret = close(ust_cmd->sock);
1914 if (ret < 0) {
1915 PERROR("close ust sock dispatch %d", ust_cmd->sock);
6620da75 1916 }
51dec90d 1917 lttng_fd_put(LTTNG_FD_APPS, 1);
d88aee68 1918 free(wait_node);
7972aab2 1919 free(ust_cmd);
d0b96690
DG
1920 continue;
1921 }
1922 /*
1923 * Add application to the wait queue so we can set the notify
1924 * socket before putting this object in the global ht.
1925 */
f45e313d
DG
1926 cds_list_add(&wait_node->head, &wait_queue.head);
1927 wait_queue.count++;
d0b96690 1928
7972aab2 1929 free(ust_cmd);
d0b96690
DG
1930 /*
1931 * We have to continue here since we don't have the notify
1932 * socket and the application MUST be added to the hash table
1933 * only at that moment.
1934 */
1935 continue;
1936 } else {
1937 /*
1938 * Look for the application in the local wait queue and set the
1939 * notify socket if found.
1940 */
d88aee68 1941 cds_list_for_each_entry_safe(wait_node, tmp_wait_node,
f45e313d 1942 &wait_queue.head, head) {
12e2b881 1943 health_code_update();
d0b96690
DG
1944 if (wait_node->app->pid == ust_cmd->reg_msg.pid) {
1945 wait_node->app->notify_sock = ust_cmd->sock;
1946 cds_list_del(&wait_node->head);
f45e313d 1947 wait_queue.count--;
d0b96690
DG
1948 app = wait_node->app;
1949 free(wait_node);
1950 DBG3("UST app notify socket %d is set", ust_cmd->sock);
1951 break;
1952 }
1953 }
020d7f60
DG
1954
1955 /*
1956 * With no application at this stage the received socket is
1957 * basically useless so close it before we free the cmd data
1958 * structure for good.
1959 */
1960 if (!app) {
1961 ret = close(ust_cmd->sock);
1962 if (ret < 0) {
1963 PERROR("close ust sock dispatch %d", ust_cmd->sock);
1964 }
51dec90d 1965 lttng_fd_put(LTTNG_FD_APPS, 1);
020d7f60 1966 }
7972aab2 1967 free(ust_cmd);
d0b96690
DG
1968 }
1969
1970 if (app) {
d0b96690
DG
1971 /*
1972 * @session_lock_list
1973 *
1974 * Lock the global session list so from the register up to the
1975 * registration done message, no thread can see the application
1976 * and change its state.
1977 */
1978 session_lock_list();
1979 rcu_read_lock();
d88aee68 1980
d0b96690
DG
1981 /*
1982 * Add application to the global hash table. This needs to be
1983 * done before the update to the UST registry can locate the
1984 * application.
1985 */
1986 ust_app_add(app);
d88aee68
DG
1987
1988 /* Set app version. This call will print an error if needed. */
1989 (void) ust_app_version(app);
1990
1991 /* Send notify socket through the notify pipe. */
1992 ret = send_socket_to_thread(apps_cmd_notify_pipe[1],
1993 app->notify_sock);
1994 if (ret < 0) {
1995 rcu_read_unlock();
1996 session_unlock_list();
b85dc84c
DG
1997 /*
1998 * No notify thread, stop the UST tracing. However, this is
1999 * not an internal error of the this thread thus setting
2000 * the health error code to a normal exit.
2001 */
2002 err = 0;
d88aee68 2003 goto error;
6620da75 2004 }
d88aee68 2005
d0b96690
DG
2006 /*
2007 * Update newly registered application with the tracing
2008 * registry info already enabled information.
2009 */
2010 update_ust_app(app->sock);
d88aee68
DG
2011
2012 /*
2013 * Don't care about return value. Let the manage apps threads
2014 * handle app unregistration upon socket close.
2015 */
fb45065e 2016 (void) ust_app_register_done(app);
d88aee68
DG
2017
2018 /*
2019 * Even if the application socket has been closed, send the app
2020 * to the thread and unregistration will take place at that
2021 * place.
2022 */
2023 ret = send_socket_to_thread(apps_cmd_pipe[1], app->sock);
d0b96690 2024 if (ret < 0) {
d88aee68
DG
2025 rcu_read_unlock();
2026 session_unlock_list();
b85dc84c
DG
2027 /*
2028 * No apps. thread, stop the UST tracing. However, this is
2029 * not an internal error of the this thread thus setting
2030 * the health error code to a normal exit.
2031 */
2032 err = 0;
d88aee68 2033 goto error;
d0b96690 2034 }
d88aee68 2035
d0b96690
DG
2036 rcu_read_unlock();
2037 session_unlock_list();
099e26bd 2038 }
099e26bd
DG
2039 } while (node != NULL);
2040
12e2b881 2041 health_poll_entry();
099e26bd
DG
2042 /* Futex wait on queue. Blocking call on futex() */
2043 futex_nto1_wait(&ust_cmd_queue.futex);
12e2b881 2044 health_poll_exit();
099e26bd 2045 }
12e2b881
MD
2046 /* Normal exit, no error */
2047 err = 0;
099e26bd
DG
2048
2049error:
d88aee68
DG
2050 /* Clean up wait queue. */
2051 cds_list_for_each_entry_safe(wait_node, tmp_wait_node,
f45e313d 2052 &wait_queue.head, head) {
d88aee68 2053 cds_list_del(&wait_node->head);
f45e313d 2054 wait_queue.count--;
d88aee68
DG
2055 free(wait_node);
2056 }
2057
772b8f4d
MD
2058 /* Empty command queue. */
2059 for (;;) {
2060 /* Dequeue command for registration */
2061 node = cds_wfcq_dequeue_blocking(&ust_cmd_queue.head, &ust_cmd_queue.tail);
2062 if (node == NULL) {
2063 break;
2064 }
2065 ust_cmd = caa_container_of(node, struct ust_command, node);
2066 ret = close(ust_cmd->sock);
2067 if (ret < 0) {
2068 PERROR("close ust sock exit dispatch %d", ust_cmd->sock);
2069 }
2070 lttng_fd_put(LTTNG_FD_APPS, 1);
2071 free(ust_cmd);
2072 }
2073
9ad42ec1 2074error_testpoint:
099e26bd 2075 DBG("Dispatch thread dying");
12e2b881
MD
2076 if (err) {
2077 health_error();
2078 ERR("Health error occurred in %s", __func__);
2079 }
8782cc74 2080 health_unregister(health_sessiond);
967e3668 2081 rcu_unregister_thread();
099e26bd
DG
2082 return NULL;
2083}
2084
2085/*
2086 * This thread manage application registration.
2087 */
2088static void *thread_registration_apps(void *data)
1d4b027a 2089{
139ac872 2090 int sock = -1, i, ret, pollfd, err = -1;
5eb91c98
DG
2091 uint32_t revents, nb_fd;
2092 struct lttng_poll_event events;
099e26bd
DG
2093 /*
2094 * Get allocated in this thread, enqueued to a global queue, dequeued and
2095 * freed in the manage apps thread.
2096 */
2097 struct ust_command *ust_cmd = NULL;
1d4b027a 2098
099e26bd 2099 DBG("[thread] Manage application registration started");
1d4b027a 2100
6c71277b 2101 health_register(health_sessiond, HEALTH_SESSIOND_TYPE_APP_REG);
927ca06a 2102
e547b070 2103 if (testpoint(sessiond_thread_registration_apps)) {
6993eeb3
CB
2104 goto error_testpoint;
2105 }
8ac94142 2106
1d4b027a
DG
2107 ret = lttcomm_listen_unix_sock(apps_sock);
2108 if (ret < 0) {
76d7553f 2109 goto error_listen;
1d4b027a
DG
2110 }
2111
5eb91c98
DG
2112 /*
2113 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
2114 * more will be added to this poll set.
2115 */
d0b96690 2116 ret = sessiond_set_thread_pollset(&events, 2);
5eb91c98 2117 if (ret < 0) {
76d7553f 2118 goto error_create_poll;
5eb91c98 2119 }
273ea72c 2120
5eb91c98
DG
2121 /* Add the application registration socket */
2122 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
2123 if (ret < 0) {
76d7553f 2124 goto error_poll_add;
5eb91c98 2125 }
273ea72c 2126
1d4b027a 2127 /* Notify all applications to register */
0fdd1e2c
DG
2128 ret = notify_ust_apps(1);
2129 if (ret < 0) {
2130 ERR("Failed to notify applications or create the wait shared memory.\n"
54d01ffb
DG
2131 "Execution continues but there might be problem for already\n"
2132 "running applications that wishes to register.");
0fdd1e2c 2133 }
1d4b027a
DG
2134
2135 while (1) {
2136 DBG("Accepting application registration");
273ea72c
DG
2137
2138 /* Inifinite blocking call, waiting for transmission */
88f2b785 2139 restart:
a78af745 2140 health_poll_entry();
5eb91c98 2141 ret = lttng_poll_wait(&events, -1);
a78af745 2142 health_poll_exit();
273ea72c 2143 if (ret < 0) {
88f2b785
MD
2144 /*
2145 * Restart interrupted system call.
2146 */
2147 if (errno == EINTR) {
2148 goto restart;
2149 }
273ea72c
DG
2150 goto error;
2151 }
2152
0d9c5d77
DG
2153 nb_fd = ret;
2154
5eb91c98 2155 for (i = 0; i < nb_fd; i++) {
840cb59c 2156 health_code_update();
139ac872 2157
5eb91c98
DG
2158 /* Fetch once the poll data */
2159 revents = LTTNG_POLL_GETEV(&events, i);
2160 pollfd = LTTNG_POLL_GETFD(&events, i);
273ea72c 2161
fd20dac9
MD
2162 if (!revents) {
2163 /* No activity for this FD (poll implementation). */
2164 continue;
2165 }
2166
5eb91c98 2167 /* Thread quit pipe has been closed. Killing thread. */
d0b96690 2168 ret = sessiond_check_thread_quit_pipe(pollfd, revents);
5eb91c98 2169 if (ret) {
139ac872
MD
2170 err = 0;
2171 goto exit;
90014c57 2172 }
1d4b027a 2173
5eb91c98
DG
2174 /* Event on the registration socket */
2175 if (pollfd == apps_sock) {
03e43155 2176 if (revents & LPOLLIN) {
5eb91c98
DG
2177 sock = lttcomm_accept_unix_sock(apps_sock);
2178 if (sock < 0) {
2179 goto error;
2180 }
099e26bd 2181
16c5c8fa
DG
2182 /*
2183 * Set socket timeout for both receiving and ending.
2184 * app_socket_timeout is in seconds, whereas
2185 * lttcomm_setsockopt_rcv_timeout and
2186 * lttcomm_setsockopt_snd_timeout expect msec as
2187 * parameter.
2188 */
e6142f2e 2189 if (config.app_socket_timeout >= 0) {
28ce0ff2 2190 (void) lttcomm_setsockopt_rcv_timeout(sock,
e6142f2e 2191 config.app_socket_timeout * 1000);
28ce0ff2 2192 (void) lttcomm_setsockopt_snd_timeout(sock,
e6142f2e 2193 config.app_socket_timeout * 1000);
28ce0ff2 2194 }
16c5c8fa 2195
b662582b
DG
2196 /*
2197 * Set the CLOEXEC flag. Return code is useless because
2198 * either way, the show must go on.
2199 */
2200 (void) utils_set_fd_cloexec(sock);
2201
5eb91c98 2202 /* Create UST registration command for enqueuing */
ba7f0ae5 2203 ust_cmd = zmalloc(sizeof(struct ust_command));
5eb91c98 2204 if (ust_cmd == NULL) {
76d7553f 2205 PERROR("ust command zmalloc");
41ed8e47
MD
2206 ret = close(sock);
2207 if (ret) {
2208 PERROR("close");
2209 }
5eb91c98
DG
2210 goto error;
2211 }
1d4b027a 2212
5eb91c98
DG
2213 /*
2214 * Using message-based transmissions to ensure we don't
2215 * have to deal with partially received messages.
2216 */
4063050c
MD
2217 ret = lttng_fd_get(LTTNG_FD_APPS, 1);
2218 if (ret < 0) {
2219 ERR("Exhausted file descriptors allowed for applications.");
2220 free(ust_cmd);
2221 ret = close(sock);
2222 if (ret) {
2223 PERROR("close");
2224 }
2225 sock = -1;
2226 continue;
2227 }
d88aee68 2228
840cb59c 2229 health_code_update();
d0b96690
DG
2230 ret = ust_app_recv_registration(sock, &ust_cmd->reg_msg);
2231 if (ret < 0) {
5eb91c98 2232 free(ust_cmd);
d0b96690 2233 /* Close socket of the application. */
76d7553f
MD
2234 ret = close(sock);
2235 if (ret) {
2236 PERROR("close");
2237 }
4063050c 2238 lttng_fd_put(LTTNG_FD_APPS, 1);
76d7553f 2239 sock = -1;
5eb91c98
DG
2240 continue;
2241 }
840cb59c 2242 health_code_update();
099e26bd 2243
5eb91c98 2244 ust_cmd->sock = sock;
34a2494f 2245 sock = -1;
099e26bd 2246
5eb91c98
DG
2247 DBG("UST registration received with pid:%d ppid:%d uid:%d"
2248 " gid:%d sock:%d name:%s (version %d.%d)",
2249 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
2250 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
2251 ust_cmd->sock, ust_cmd->reg_msg.name,
2252 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
54d01ffb 2253
5eb91c98
DG
2254 /*
2255 * Lock free enqueue the registration request. The red pill
54d01ffb 2256 * has been taken! This apps will be part of the *system*.
5eb91c98 2257 */
8bdee6e2 2258 cds_wfcq_enqueue(&ust_cmd_queue.head, &ust_cmd_queue.tail, &ust_cmd->node);
5eb91c98
DG
2259
2260 /*
2261 * Wake the registration queue futex. Implicit memory
8bdee6e2 2262 * barrier with the exchange in cds_wfcq_enqueue.
5eb91c98
DG
2263 */
2264 futex_nto1_wake(&ust_cmd_queue.futex);
03e43155
MD
2265 } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
2266 ERR("Register apps socket poll error");
2267 goto error;
2268 } else {
2269 ERR("Unexpected poll events %u for sock %d", revents, pollfd);
2270 goto error;
5eb91c98
DG
2271 }
2272 }
90014c57 2273 }
1d4b027a
DG
2274 }
2275
139ac872 2276exit:
1d4b027a 2277error:
0fdd1e2c
DG
2278 /* Notify that the registration thread is gone */
2279 notify_ust_apps(0);
2280
a4b35e07 2281 if (apps_sock >= 0) {
76d7553f
MD
2282 ret = close(apps_sock);
2283 if (ret) {
2284 PERROR("close");
2285 }
a4b35e07 2286 }
46c3f085 2287 if (sock >= 0) {
76d7553f
MD
2288 ret = close(sock);
2289 if (ret) {
2290 PERROR("close");
2291 }
4063050c 2292 lttng_fd_put(LTTNG_FD_APPS, 1);
a4b35e07 2293 }
e6142f2e 2294 unlink(config.apps_unix_sock_path.value);
0fdd1e2c 2295
76d7553f 2296error_poll_add:
5eb91c98 2297 lttng_poll_clean(&events);
76d7553f
MD
2298error_listen:
2299error_create_poll:
6993eeb3 2300error_testpoint:
76d7553f 2301 DBG("UST Registration thread cleanup complete");
9ad42ec1
MD
2302 if (err) {
2303 health_error();
2304 ERR("Health error occurred in %s", __func__);
2305 }
8782cc74 2306 health_unregister(health_sessiond);
5eb91c98 2307
1d4b027a
DG
2308 return NULL;
2309}
2310
8c0faa1d 2311/*
3bd1e081 2312 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
d063d709 2313 * exec or it will fails.
8c0faa1d 2314 */
3bd1e081 2315static int spawn_consumer_thread(struct consumer_data *consumer_data)
8c0faa1d 2316{
a23ec3a7 2317 int ret, clock_ret;
ee0b0061
DG
2318 struct timespec timeout;
2319
13a7bce3
JG
2320 /*
2321 * Make sure we set the readiness flag to 0 because we are NOT ready.
2322 * This access to consumer_thread_is_ready does not need to be
2323 * protected by consumer_data.cond_mutex (yet) since the consumer
2324 * management thread has not been started at this point.
2325 */
a23ec3a7 2326 consumer_data->consumer_thread_is_ready = 0;
8c0faa1d 2327
a23ec3a7
DG
2328 /* Setup pthread condition */
2329 ret = pthread_condattr_init(&consumer_data->condattr);
4a15001e 2330 if (ret) {
a23ec3a7
DG
2331 errno = ret;
2332 PERROR("pthread_condattr_init consumer data");
2333 goto error;
2334 }
2335
2336 /*
2337 * Set the monotonic clock in order to make sure we DO NOT jump in time
2338 * between the clock_gettime() call and the timedwait call. See bug #324
2339 * for a more details and how we noticed it.
2340 */
2341 ret = pthread_condattr_setclock(&consumer_data->condattr, CLOCK_MONOTONIC);
4a15001e 2342 if (ret) {
a23ec3a7
DG
2343 errno = ret;
2344 PERROR("pthread_condattr_setclock consumer data");
ee0b0061
DG
2345 goto error;
2346 }
8c0faa1d 2347
a23ec3a7 2348 ret = pthread_cond_init(&consumer_data->cond, &consumer_data->condattr);
4a15001e 2349 if (ret) {
a23ec3a7
DG
2350 errno = ret;
2351 PERROR("pthread_cond_init consumer data");
2352 goto error;
2353 }
2354
1a1a34b4
MJ
2355 ret = pthread_create(&consumer_data->thread, default_pthread_attr(),
2356 thread_manage_consumer, consumer_data);
4a15001e
MD
2357 if (ret) {
2358 errno = ret;
3bd1e081 2359 PERROR("pthread_create consumer");
ee0b0061 2360 ret = -1;
8c0faa1d
DG
2361 goto error;
2362 }
2363
a23ec3a7
DG
2364 /* We are about to wait on a pthread condition */
2365 pthread_mutex_lock(&consumer_data->cond_mutex);
2366
ee0b0061 2367 /* Get time for sem_timedwait absolute timeout */
389fbf04 2368 clock_ret = lttng_clock_gettime(CLOCK_MONOTONIC, &timeout);
a23ec3a7
DG
2369 /*
2370 * Set the timeout for the condition timed wait even if the clock gettime
2371 * call fails since we might loop on that call and we want to avoid to
2372 * increment the timeout too many times.
2373 */
2374 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
2375
2376 /*
2377 * The following loop COULD be skipped in some conditions so this is why we
2378 * set ret to 0 in order to make sure at least one round of the loop is
2379 * done.
2380 */
2381 ret = 0;
2382
2383 /*
2384 * Loop until the condition is reached or when a timeout is reached. Note
2385 * that the pthread_cond_timedwait(P) man page specifies that EINTR can NOT
2386 * be returned but the pthread_cond(3), from the glibc-doc, says that it is
2387 * possible. This loop does not take any chances and works with both of
2388 * them.
2389 */
2390 while (!consumer_data->consumer_thread_is_ready && ret != ETIMEDOUT) {
2391 if (clock_ret < 0) {
2392 PERROR("clock_gettime spawn consumer");
2393 /* Infinite wait for the consumerd thread to be ready */
2394 ret = pthread_cond_wait(&consumer_data->cond,
2395 &consumer_data->cond_mutex);
2396 } else {
2397 ret = pthread_cond_timedwait(&consumer_data->cond,
2398 &consumer_data->cond_mutex, &timeout);
2399 }
ee0b0061 2400 }
8c0faa1d 2401
a23ec3a7
DG
2402 /* Release the pthread condition */
2403 pthread_mutex_unlock(&consumer_data->cond_mutex);
2404
2405 if (ret != 0) {
2406 errno = ret;
2407 if (ret == ETIMEDOUT) {
4282f9a3
DG
2408 int pth_ret;
2409
ee0b0061
DG
2410 /*
2411 * Call has timed out so we kill the kconsumerd_thread and return
2412 * an error.
2413 */
a23ec3a7
DG
2414 ERR("Condition timed out. The consumer thread was never ready."
2415 " Killing it");
4282f9a3
DG
2416 pth_ret = pthread_cancel(consumer_data->thread);
2417 if (pth_ret < 0) {
3bd1e081 2418 PERROR("pthread_cancel consumer thread");
ee0b0061
DG
2419 }
2420 } else {
a23ec3a7 2421 PERROR("pthread_cond_wait failed consumer thread");
ee0b0061 2422 }
4282f9a3
DG
2423 /* Caller is expecting a negative value on failure. */
2424 ret = -1;
ee0b0061
DG
2425 goto error;
2426 }
2427
3bd1e081
MD
2428 pthread_mutex_lock(&consumer_data->pid_mutex);
2429 if (consumer_data->pid == 0) {
a23ec3a7 2430 ERR("Consumerd did not start");
3bd1e081 2431 pthread_mutex_unlock(&consumer_data->pid_mutex);
712ea556
DG
2432 goto error;
2433 }
3bd1e081 2434 pthread_mutex_unlock(&consumer_data->pid_mutex);
712ea556 2435
8c0faa1d
DG
2436 return 0;
2437
2438error:
2439 return ret;
2440}
2441
d9800920 2442/*
3bd1e081 2443 * Join consumer thread
d9800920 2444 */
3bd1e081 2445static int join_consumer_thread(struct consumer_data *consumer_data)
cf3af59e
MD
2446{
2447 void *status;
cf3af59e 2448
e8209f6b
DG
2449 /* Consumer pid must be a real one. */
2450 if (consumer_data->pid > 0) {
c617c0c6 2451 int ret;
3bd1e081 2452 ret = kill(consumer_data->pid, SIGTERM);
cf3af59e 2453 if (ret) {
4a15001e 2454 PERROR("Error killing consumer daemon");
cf3af59e
MD
2455 return ret;
2456 }
3bd1e081 2457 return pthread_join(consumer_data->thread, &status);
cf3af59e
MD
2458 } else {
2459 return 0;
2460 }
2461}
2462
8c0faa1d 2463/*
3bd1e081 2464 * Fork and exec a consumer daemon (consumerd).
8c0faa1d 2465 *
d063d709 2466 * Return pid if successful else -1.
8c0faa1d 2467 */
3bd1e081 2468static pid_t spawn_consumerd(struct consumer_data *consumer_data)
8c0faa1d
DG
2469{
2470 int ret;
2471 pid_t pid;
94c55f17 2472 const char *consumer_to_use;
53086306 2473 const char *verbosity;
94c55f17 2474 struct stat st;
8c0faa1d 2475
3bd1e081 2476 DBG("Spawning consumerd");
c49dc785 2477
8c0faa1d
DG
2478 pid = fork();
2479 if (pid == 0) {
2480 /*
3bd1e081 2481 * Exec consumerd.
8c0faa1d 2482 */
e6142f2e 2483 if (config.verbose_consumer) {
53086306 2484 verbosity = "--verbose";
4421f712 2485 } else if (lttng_opt_quiet) {
53086306 2486 verbosity = "--quiet";
4421f712
DG
2487 } else {
2488 verbosity = "";
53086306 2489 }
4421f712 2490
3bd1e081
MD
2491 switch (consumer_data->type) {
2492 case LTTNG_CONSUMER_KERNEL:
94c55f17 2493 /*
c7704d57
DG
2494 * Find out which consumerd to execute. We will first try the
2495 * 64-bit path, then the sessiond's installation directory, and
2496 * fallback on the 32-bit one,
94c55f17 2497 */
63a799e8 2498 DBG3("Looking for a kernel consumer at these locations:");
59ee5091 2499 DBG3(" 1) %s", config.consumerd64_bin_path.value ? : "NULL");
e6142f2e 2500 DBG3(" 2) %s/%s", INSTALL_BIN_PATH, DEFAULT_CONSUMERD_FILE);
59ee5091 2501 DBG3(" 3) %s", config.consumerd32_bin_path.value ? : "NULL");
e6142f2e 2502 if (stat(config.consumerd64_bin_path.value, &st) == 0) {
63a799e8 2503 DBG3("Found location #1");
e6142f2e
JG
2504 consumer_to_use = config.consumerd64_bin_path.value;
2505 } else if (stat(INSTALL_BIN_PATH "/" DEFAULT_CONSUMERD_FILE, &st) == 0) {
63a799e8 2506 DBG3("Found location #2");
e6142f2e
JG
2507 consumer_to_use = INSTALL_BIN_PATH "/" DEFAULT_CONSUMERD_FILE;
2508 } else if (stat(config.consumerd32_bin_path.value, &st) == 0) {
63a799e8 2509 DBG3("Found location #3");
e6142f2e 2510 consumer_to_use = config.consumerd32_bin_path.value;
94c55f17 2511 } else {
63a799e8 2512 DBG("Could not find any valid consumerd executable");
4282f9a3 2513 ret = -EINVAL;
3d678709 2514 goto error;
94c55f17
AM
2515 }
2516 DBG("Using kernel consumer at: %s", consumer_to_use);
6e2cc8d8 2517 (void) execl(consumer_to_use,
94c55f17
AM
2518 "lttng-consumerd", verbosity, "-k",
2519 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
2520 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
e6142f2e 2521 "--group", config.tracing_group_name.value,
94c55f17 2522 NULL);
3bd1e081 2523 break;
7753dea8
MD
2524 case LTTNG_CONSUMER64_UST:
2525 {
46b23495 2526 if (config.consumerd64_lib_dir.value) {
8f4905da
MD
2527 char *tmp;
2528 size_t tmplen;
ddaec4a2 2529 char *tmpnew;
8f4905da 2530
e8fa9fb0 2531 tmp = lttng_secure_getenv("LD_LIBRARY_PATH");
8f4905da
MD
2532 if (!tmp) {
2533 tmp = "";
2534 }
d222983e 2535 tmplen = strlen(config.consumerd64_lib_dir.value) + 1 /* : */ + strlen(tmp);
8f4905da
MD
2536 tmpnew = zmalloc(tmplen + 1 /* \0 */);
2537 if (!tmpnew) {
2538 ret = -ENOMEM;
2539 goto error;
2540 }
e6142f2e 2541 strcat(tmpnew, config.consumerd64_lib_dir.value);
8f4905da
MD
2542 if (tmp[0] != '\0') {
2543 strcat(tmpnew, ":");
2544 strcat(tmpnew, tmp);
2545 }
d222983e 2546 ret = setenv("LD_LIBRARY_PATH", tmpnew, 1);
ddaec4a2 2547 free(tmpnew);
8f4905da
MD
2548 if (ret) {
2549 ret = -errno;
2550 goto error;
2551 }
2552 }
e6142f2e
JG
2553 DBG("Using 64-bit UST consumer at: %s", config.consumerd64_bin_path.value);
2554 (void) execl(config.consumerd64_bin_path.value, "lttng-consumerd", verbosity, "-u",
7753dea8
MD
2555 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
2556 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
e6142f2e 2557 "--group", config.tracing_group_name.value,
7753dea8 2558 NULL);
3bd1e081 2559 break;
7753dea8
MD
2560 }
2561 case LTTNG_CONSUMER32_UST:
2562 {
46b23495 2563 if (config.consumerd32_lib_dir.value) {
8f4905da
MD
2564 char *tmp;
2565 size_t tmplen;
ddaec4a2 2566 char *tmpnew;
8f4905da 2567
e8fa9fb0 2568 tmp = lttng_secure_getenv("LD_LIBRARY_PATH");
8f4905da
MD
2569 if (!tmp) {
2570 tmp = "";
2571 }
d222983e 2572 tmplen = strlen(config.consumerd32_lib_dir.value) + 1 /* : */ + strlen(tmp);
8f4905da
MD
2573 tmpnew = zmalloc(tmplen + 1 /* \0 */);
2574 if (!tmpnew) {
2575 ret = -ENOMEM;
2576 goto error;
2577 }
e6142f2e 2578 strcat(tmpnew, config.consumerd32_lib_dir.value);
8f4905da
MD
2579 if (tmp[0] != '\0') {
2580 strcat(tmpnew, ":");
2581 strcat(tmpnew, tmp);
2582 }
d222983e 2583 ret = setenv("LD_LIBRARY_PATH", tmpnew, 1);
ddaec4a2 2584 free(tmpnew);
8f4905da
MD
2585 if (ret) {
2586 ret = -errno;
2587 goto error;
2588 }
2589 }
e6142f2e
JG
2590 DBG("Using 32-bit UST consumer at: %s", config.consumerd32_bin_path.value);
2591 (void) execl(config.consumerd32_bin_path.value, "lttng-consumerd", verbosity, "-u",
7753dea8
MD
2592 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
2593 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
e6142f2e 2594 "--group", config.tracing_group_name.value,
7753dea8
MD
2595 NULL);
2596 break;
2597 }
3bd1e081 2598 default:
b60e7183 2599 ERR("unknown consumer type");
e9d6b496 2600 errno = 0;
3bd1e081 2601 }
8c0faa1d 2602 if (errno != 0) {
4282f9a3 2603 PERROR("Consumer execl()");
8c0faa1d 2604 }
4282f9a3 2605 /* Reaching this point, we got a failure on our execl(). */
8c0faa1d
DG
2606 exit(EXIT_FAILURE);
2607 } else if (pid > 0) {
2608 ret = pid;
8c0faa1d 2609 } else {
76d7553f 2610 PERROR("start consumer fork");
8c0faa1d 2611 ret = -errno;
8c0faa1d 2612 }
8f4905da 2613error:
8c0faa1d
DG
2614 return ret;
2615}
2616
693bd40b 2617/*
3bd1e081 2618 * Spawn the consumerd daemon and session daemon thread.
693bd40b 2619 */
3bd1e081 2620static int start_consumerd(struct consumer_data *consumer_data)
693bd40b 2621{
c617c0c6 2622 int ret;
edb8b045
DG
2623
2624 /*
2625 * Set the listen() state on the socket since there is a possible race
2626 * between the exec() of the consumer daemon and this call if place in the
2627 * consumer thread. See bug #366 for more details.
2628 */
2629 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
2630 if (ret < 0) {
2631 goto error;
2632 }
693bd40b 2633
3bd1e081
MD
2634 pthread_mutex_lock(&consumer_data->pid_mutex);
2635 if (consumer_data->pid != 0) {
2636 pthread_mutex_unlock(&consumer_data->pid_mutex);
c49dc785
DG
2637 goto end;
2638 }
693bd40b 2639
3bd1e081 2640 ret = spawn_consumerd(consumer_data);
c49dc785 2641 if (ret < 0) {
3bd1e081
MD
2642 ERR("Spawning consumerd failed");
2643 pthread_mutex_unlock(&consumer_data->pid_mutex);
c49dc785 2644 goto error;
693bd40b 2645 }
c49dc785 2646
3bd1e081
MD
2647 /* Setting up the consumer_data pid */
2648 consumer_data->pid = ret;
48842b30 2649 DBG2("Consumer pid %d", consumer_data->pid);
3bd1e081 2650 pthread_mutex_unlock(&consumer_data->pid_mutex);
693bd40b 2651
3bd1e081
MD
2652 DBG2("Spawning consumer control thread");
2653 ret = spawn_consumer_thread(consumer_data);
693bd40b 2654 if (ret < 0) {
3bd1e081 2655 ERR("Fatal error spawning consumer control thread");
693bd40b
DG
2656 goto error;
2657 }
2658
c49dc785 2659end:
693bd40b
DG
2660 return 0;
2661
2662error:
331744e3 2663 /* Cleanup already created sockets on error. */
edb8b045 2664 if (consumer_data->err_sock >= 0) {
c617c0c6
MD
2665 int err;
2666
edb8b045
DG
2667 err = close(consumer_data->err_sock);
2668 if (err < 0) {
2669 PERROR("close consumer data error socket");
2670 }
2671 }
693bd40b
DG
2672 return ret;
2673}
2674
b73401da 2675/*
096102bd 2676 * Setup necessary data for kernel tracer action.
b73401da 2677 */
096102bd 2678static int init_kernel_tracer(void)
b73401da
DG
2679{
2680 int ret;
b73401da 2681
096102bd
DG
2682 /* Modprobe lttng kernel modules */
2683 ret = modprobe_lttng_control();
b73401da 2684 if (ret < 0) {
b73401da
DG
2685 goto error;
2686 }
2687
096102bd
DG
2688 /* Open debugfs lttng */
2689 kernel_tracer_fd = open(module_proc_lttng, O_RDWR);
2690 if (kernel_tracer_fd < 0) {
2691 DBG("Failed to open %s", module_proc_lttng);
2f77fc4b 2692 goto error_open;
54d01ffb
DG
2693 }
2694
2f77fc4b 2695 /* Validate kernel version */
88076e89
JD
2696 ret = kernel_validate_version(kernel_tracer_fd, &kernel_tracer_version,
2697 &kernel_tracer_abi_version);
2f77fc4b
DG
2698 if (ret < 0) {
2699 goto error_version;
b551a063 2700 }
54d01ffb 2701
2f77fc4b
DG
2702 ret = modprobe_lttng_data();
2703 if (ret < 0) {
2704 goto error_modules;
54d01ffb
DG
2705 }
2706
6e21424e
JR
2707 ret = kernel_supports_ring_buffer_snapshot_sample_positions(
2708 kernel_tracer_fd);
2709 if (ret < 0) {
2710 goto error_modules;
2711 }
2712
2713 if (ret < 1) {
2714 WARN("Kernel tracer does not support buffer monitoring. "
2715 "The monitoring timer of channels in the kernel domain "
2716 "will be set to 0 (disabled).");
2717 }
2718
2f77fc4b
DG
2719 DBG("Kernel tracer fd %d", kernel_tracer_fd);
2720 return 0;
2721
2722error_version:
2723 modprobe_remove_lttng_control();
2724 ret = close(kernel_tracer_fd);
2725 if (ret) {
2726 PERROR("close");
b551a063 2727 }
2f77fc4b 2728 kernel_tracer_fd = -1;
f73fabfd 2729 return LTTNG_ERR_KERN_VERSION;
b551a063 2730
2f77fc4b
DG
2731error_modules:
2732 ret = close(kernel_tracer_fd);
2733 if (ret) {
2734 PERROR("close");
b551a063 2735 }
54d01ffb 2736
2f77fc4b
DG
2737error_open:
2738 modprobe_remove_lttng_control();
54d01ffb
DG
2739
2740error:
2f77fc4b
DG
2741 WARN("No kernel tracer available");
2742 kernel_tracer_fd = -1;
2743 if (!is_root) {
f73fabfd 2744 return LTTNG_ERR_NEED_ROOT_SESSIOND;
2f77fc4b 2745 } else {
f73fabfd 2746 return LTTNG_ERR_KERN_NA;
2f77fc4b 2747 }
54d01ffb
DG
2748}
2749
2f77fc4b 2750
54d01ffb 2751/*
2f77fc4b
DG
2752 * Copy consumer output from the tracing session to the domain session. The
2753 * function also applies the right modification on a per domain basis for the
2754 * trace files destination directory.
36b588ed
MD
2755 *
2756 * Should *NOT* be called with RCU read-side lock held.
54d01ffb 2757 */
2f77fc4b 2758static int copy_session_consumer(int domain, struct ltt_session *session)
54d01ffb
DG
2759{
2760 int ret;
2f77fc4b
DG
2761 const char *dir_name;
2762 struct consumer_output *consumer;
2763
2764 assert(session);
2765 assert(session->consumer);
54d01ffb 2766
b551a063
DG
2767 switch (domain) {
2768 case LTTNG_DOMAIN_KERNEL:
2f77fc4b 2769 DBG3("Copying tracing session consumer output in kernel session");
09a90bcd
DG
2770 /*
2771 * XXX: We should audit the session creation and what this function
2772 * does "extra" in order to avoid a destroy since this function is used
2773 * in the domain session creation (kernel and ust) only. Same for UST
2774 * domain.
2775 */
2776 if (session->kernel_session->consumer) {
6addfa37 2777 consumer_output_put(session->kernel_session->consumer);
09a90bcd 2778 }
2f77fc4b
DG
2779 session->kernel_session->consumer =
2780 consumer_copy_output(session->consumer);
2781 /* Ease our life a bit for the next part */
2782 consumer = session->kernel_session->consumer;
2783 dir_name = DEFAULT_KERNEL_TRACE_DIR;
b551a063 2784 break;
f20baf8e 2785 case LTTNG_DOMAIN_JUL:
5cdb6027 2786 case LTTNG_DOMAIN_LOG4J:
0e115563 2787 case LTTNG_DOMAIN_PYTHON:
b551a063 2788 case LTTNG_DOMAIN_UST:
2f77fc4b 2789 DBG3("Copying tracing session consumer output in UST session");
09a90bcd 2790 if (session->ust_session->consumer) {
6addfa37 2791 consumer_output_put(session->ust_session->consumer);
09a90bcd 2792 }
2f77fc4b
DG
2793 session->ust_session->consumer =
2794 consumer_copy_output(session->consumer);
2795 /* Ease our life a bit for the next part */
2796 consumer = session->ust_session->consumer;
2797 dir_name = DEFAULT_UST_TRACE_DIR;
b551a063
DG
2798 break;
2799 default:
f73fabfd 2800 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
54d01ffb
DG
2801 goto error;
2802 }
2803
2f77fc4b 2804 /* Append correct directory to subdir */
c30ce0b3
CB
2805 strncat(consumer->subdir, dir_name,
2806 sizeof(consumer->subdir) - strlen(consumer->subdir) - 1);
2f77fc4b
DG
2807 DBG3("Copy session consumer subdir %s", consumer->subdir);
2808
f73fabfd 2809 ret = LTTNG_OK;
54d01ffb
DG
2810
2811error:
2812 return ret;
2813}
2814
00e2e675 2815/*
2f77fc4b 2816 * Create an UST session and add it to the session ust list.
36b588ed
MD
2817 *
2818 * Should *NOT* be called with RCU read-side lock held.
00e2e675 2819 */
2f77fc4b
DG
2820static int create_ust_session(struct ltt_session *session,
2821 struct lttng_domain *domain)
00e2e675
DG
2822{
2823 int ret;
2f77fc4b 2824 struct ltt_ust_session *lus = NULL;
00e2e675 2825
a4b92340 2826 assert(session);
2f77fc4b
DG
2827 assert(domain);
2828 assert(session->consumer);
a4b92340 2829
2f77fc4b 2830 switch (domain->type) {
f20baf8e 2831 case LTTNG_DOMAIN_JUL:
5cdb6027 2832 case LTTNG_DOMAIN_LOG4J:
0e115563 2833 case LTTNG_DOMAIN_PYTHON:
2f77fc4b
DG
2834 case LTTNG_DOMAIN_UST:
2835 break;
2836 default:
2837 ERR("Unknown UST domain on create session %d", domain->type);
f73fabfd 2838 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
00e2e675
DG
2839 goto error;
2840 }
2841
2f77fc4b
DG
2842 DBG("Creating UST session");
2843
dec56f6c 2844 lus = trace_ust_create_session(session->id);
2f77fc4b 2845 if (lus == NULL) {
f73fabfd 2846 ret = LTTNG_ERR_UST_SESS_FAIL;
a4b92340
DG
2847 goto error;
2848 }
2849
2f77fc4b
DG
2850 lus->uid = session->uid;
2851 lus->gid = session->gid;
2bba9e53 2852 lus->output_traces = session->output_traces;
27babd3a 2853 lus->snapshot_mode = session->snapshot_mode;
ecc48a90 2854 lus->live_timer_interval = session->live_timer;
2f77fc4b 2855 session->ust_session = lus;
d7ba1388 2856 if (session->shm_path[0]) {
3d071855
MD
2857 strncpy(lus->root_shm_path, session->shm_path,
2858 sizeof(lus->root_shm_path));
2859 lus->root_shm_path[sizeof(lus->root_shm_path) - 1] = '\0';
d7ba1388
MD
2860 strncpy(lus->shm_path, session->shm_path,
2861 sizeof(lus->shm_path));
2862 lus->shm_path[sizeof(lus->shm_path) - 1] = '\0';
2863 strncat(lus->shm_path, "/ust",
2864 sizeof(lus->shm_path) - strlen(lus->shm_path) - 1);
2865 }
2f77fc4b
DG
2866 /* Copy session output to the newly created UST session */
2867 ret = copy_session_consumer(domain->type, session);
f73fabfd 2868 if (ret != LTTNG_OK) {
00e2e675
DG
2869 goto error;
2870 }
2871
f73fabfd 2872 return LTTNG_OK;
00e2e675
DG
2873
2874error:
2f77fc4b
DG
2875 free(lus);
2876 session->ust_session = NULL;
00e2e675
DG
2877 return ret;
2878}
2879
2880/*
2f77fc4b 2881 * Create a kernel tracer session then create the default channel.
00e2e675 2882 */
2f77fc4b 2883static int create_kernel_session(struct ltt_session *session)
00e2e675
DG
2884{
2885 int ret;
a4b92340 2886
2f77fc4b 2887 DBG("Creating kernel session");
00e2e675 2888
2f77fc4b
DG
2889 ret = kernel_create_session(session, kernel_tracer_fd);
2890 if (ret < 0) {
f73fabfd 2891 ret = LTTNG_ERR_KERN_SESS_FAIL;
00e2e675
DG
2892 goto error;
2893 }
2894
2f77fc4b
DG
2895 /* Code flow safety */
2896 assert(session->kernel_session);
2897
2898 /* Copy session output to the newly created Kernel session */
2899 ret = copy_session_consumer(LTTNG_DOMAIN_KERNEL, session);
f73fabfd 2900 if (ret != LTTNG_OK) {
a4b92340
DG
2901 goto error;
2902 }
2903
2f77fc4b
DG
2904 session->kernel_session->uid = session->uid;
2905 session->kernel_session->gid = session->gid;
2bba9e53 2906 session->kernel_session->output_traces = session->output_traces;
27babd3a 2907 session->kernel_session->snapshot_mode = session->snapshot_mode;
00e2e675 2908
f73fabfd 2909 return LTTNG_OK;
00e2e675 2910
2f77fc4b
DG
2911error:
2912 trace_kernel_destroy_session(session->kernel_session);
2913 session->kernel_session = NULL;
2914 return ret;
2915}
00e2e675 2916
2f77fc4b
DG
2917/*
2918 * Count number of session permitted by uid/gid.
2919 */
2920static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
2921{
2922 unsigned int i = 0;
2923 struct ltt_session *session;
07424f16 2924
2f77fc4b
DG
2925 DBG("Counting number of available session for UID %d GID %d",
2926 uid, gid);
2927 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
00e2e675 2928 /*
2f77fc4b 2929 * Only list the sessions the user can control.
00e2e675 2930 */
2f77fc4b
DG
2931 if (!session_access_ok(session, uid, gid)) {
2932 continue;
2933 }
2934 i++;
a4b92340 2935 }
2f77fc4b 2936 return i;
00e2e675
DG
2937}
2938
5c408ad8
JD
2939/*
2940 * Check if the current kernel tracer supports the session rotation feature.
2941 * Return 1 if it does, 0 otherwise.
2942 */
2943static int check_rotate_compatible(void)
2944{
2945 int ret = 1;
2946
2947 if (kernel_tracer_version.major != 2 || kernel_tracer_version.minor < 11) {
2948 DBG("Kernel tracer version is not compatible with the rotation feature");
2949 ret = 0;
2950 }
2951
2952 return ret;
2953}
2954
54d01ffb
DG
2955/*
2956 * Process the command requested by the lttng client within the command
2957 * context structure. This function make sure that the return structure (llm)
2958 * is set and ready for transmission before returning.
2959 *
2960 * Return any error encountered or 0 for success.
53a80697
MD
2961 *
2962 * "sock" is only used for special-case var. len data.
36b588ed
MD
2963 *
2964 * Should *NOT* be called with RCU read-side lock held.
54d01ffb 2965 */
53a80697
MD
2966static int process_client_msg(struct command_ctx *cmd_ctx, int sock,
2967 int *sock_error)
54d01ffb 2968{
f73fabfd 2969 int ret = LTTNG_OK;
44d3bd01 2970 int need_tracing_session = 1;
2e09ba09 2971 int need_domain;
54d01ffb
DG
2972
2973 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
2974
3745d315
MD
2975 assert(!rcu_read_ongoing());
2976
53a80697
MD
2977 *sock_error = 0;
2978
2e09ba09
MD
2979 switch (cmd_ctx->lsm->cmd_type) {
2980 case LTTNG_CREATE_SESSION:
27babd3a 2981 case LTTNG_CREATE_SESSION_SNAPSHOT:
ecc48a90 2982 case LTTNG_CREATE_SESSION_LIVE:
2e09ba09
MD
2983 case LTTNG_DESTROY_SESSION:
2984 case LTTNG_LIST_SESSIONS:
2985 case LTTNG_LIST_DOMAINS:
2986 case LTTNG_START_TRACE:
2987 case LTTNG_STOP_TRACE:
6d805429 2988 case LTTNG_DATA_PENDING:
da3c9ec1
DG
2989 case LTTNG_SNAPSHOT_ADD_OUTPUT:
2990 case LTTNG_SNAPSHOT_DEL_OUTPUT:
2991 case LTTNG_SNAPSHOT_LIST_OUTPUT:
2992 case LTTNG_SNAPSHOT_RECORD:
fb198a11 2993 case LTTNG_SAVE_SESSION:
d7ba1388 2994 case LTTNG_SET_SESSION_SHM_PATH:
eded6438 2995 case LTTNG_REGENERATE_METADATA:
c2561365 2996 case LTTNG_REGENERATE_STATEDUMP:
b3530820
JG
2997 case LTTNG_REGISTER_TRIGGER:
2998 case LTTNG_UNREGISTER_TRIGGER:
5c408ad8 2999 case LTTNG_ROTATE_SESSION:
d68c9a04
JD
3000 case LTTNG_ROTATION_GET_INFO:
3001 case LTTNG_SESSION_GET_CURRENT_OUTPUT:
259c2674 3002 case LTTNG_ROTATION_SET_SCHEDULE:
329f3443
JD
3003 case LTTNG_ROTATION_SCHEDULE_GET_TIMER_PERIOD:
3004 case LTTNG_ROTATION_SCHEDULE_GET_SIZE:
2e09ba09 3005 need_domain = 0;
3aace903 3006 break;
2e09ba09
MD
3007 default:
3008 need_domain = 1;
3009 }
3010
e6142f2e 3011 if (config.no_kernel && need_domain
2e09ba09 3012 && cmd_ctx->lsm->domain.type == LTTNG_DOMAIN_KERNEL) {
531d29f9 3013 if (!is_root) {
f73fabfd 3014 ret = LTTNG_ERR_NEED_ROOT_SESSIOND;
531d29f9 3015 } else {
f73fabfd 3016 ret = LTTNG_ERR_KERN_NA;
531d29f9 3017 }
4fba7219
DG
3018 goto error;
3019 }
3020
8d3113b2
DG
3021 /* Deny register consumer if we already have a spawned consumer. */
3022 if (cmd_ctx->lsm->cmd_type == LTTNG_REGISTER_CONSUMER) {
3023 pthread_mutex_lock(&kconsumer_data.pid_mutex);
3024 if (kconsumer_data.pid > 0) {
f73fabfd 3025 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
fa317f24 3026 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
8d3113b2
DG
3027 goto error;
3028 }
3029 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3030 }
3031
54d01ffb
DG
3032 /*
3033 * Check for command that don't needs to allocate a returned payload. We do
44d3bd01 3034 * this here so we don't have to make the call for no payload at each
54d01ffb
DG
3035 * command.
3036 */
3037 switch(cmd_ctx->lsm->cmd_type) {
3038 case LTTNG_LIST_SESSIONS:
3039 case LTTNG_LIST_TRACEPOINTS:
f37d259d 3040 case LTTNG_LIST_TRACEPOINT_FIELDS:
54d01ffb
DG
3041 case LTTNG_LIST_DOMAINS:
3042 case LTTNG_LIST_CHANNELS:
3043 case LTTNG_LIST_EVENTS:
834978fd 3044 case LTTNG_LIST_SYSCALLS:
a5dfbb9d 3045 case LTTNG_LIST_TRACKER_PIDS:
5cd0780d 3046 case LTTNG_DATA_PENDING:
5c408ad8 3047 case LTTNG_ROTATE_SESSION:
d68c9a04 3048 case LTTNG_ROTATION_GET_INFO:
329f3443
JD
3049 case LTTNG_ROTATION_SCHEDULE_GET_TIMER_PERIOD:
3050 case LTTNG_ROTATION_SCHEDULE_GET_SIZE:
54d01ffb
DG
3051 break;
3052 default:
3053 /* Setup lttng message with no payload */
6e10c9b9 3054 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, NULL, 0);
54d01ffb
DG
3055 if (ret < 0) {
3056 /* This label does not try to unlock the session */
3057 goto init_setup_error;
3058 }
3059 }
3060
3061 /* Commands that DO NOT need a session. */
3062 switch (cmd_ctx->lsm->cmd_type) {
54d01ffb 3063 case LTTNG_CREATE_SESSION:
27babd3a 3064 case LTTNG_CREATE_SESSION_SNAPSHOT:
ecc48a90 3065 case LTTNG_CREATE_SESSION_LIVE:
54d01ffb
DG
3066 case LTTNG_LIST_SESSIONS:
3067 case LTTNG_LIST_TRACEPOINTS:
834978fd 3068 case LTTNG_LIST_SYSCALLS:
f37d259d 3069 case LTTNG_LIST_TRACEPOINT_FIELDS:
fb198a11 3070 case LTTNG_SAVE_SESSION:
b3530820
JG
3071 case LTTNG_REGISTER_TRIGGER:
3072 case LTTNG_UNREGISTER_TRIGGER:
44d3bd01 3073 need_tracing_session = 0;
54d01ffb
DG
3074 break;
3075 default:
3076 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
256a5576
MD
3077 /*