[lttng-tools.git] / src / bin / lttng-sessiond / manage-consumer.cpp

/*
 * Copyright (C) 2011 EfficiOS Inc.
 * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 * Copyright (C) 2013 Jérémie Galarneau <jeremie.galarneau@efficios.com>
 *
 * SPDX-License-Identifier: GPL-2.0-only
 *
 */

#include <signal.h>

#include <common/pipe.hpp>
#include <common/utils.hpp>

#include "manage-consumer.hpp"
#include "testpoint.hpp"
#include "health-sessiond.hpp"
#include "utils.hpp"
#include "thread.hpp"
#include "ust-consumer.hpp"

namespace {
struct thread_notifiers {
	struct lttng_pipe *quit_pipe;
	struct consumer_data *consumer_data;
	sem_t ready;
	int initialization_result;
};
} /* namespace */

static void mark_thread_as_ready(struct thread_notifiers *notifiers)
{
	DBG("Marking consumer management thread as ready");
	notifiers->initialization_result = 0;
	sem_post(&notifiers->ready);
}

static void mark_thread_intialization_as_failed(
		struct thread_notifiers *notifiers)
{
	ERR("Consumer management thread entering error state");
	notifiers->initialization_result = -1;
	sem_post(&notifiers->ready);
}

static void wait_until_thread_is_ready(struct thread_notifiers *notifiers)
{
	DBG("Waiting for consumer management thread to be ready");
	sem_wait(&notifiers->ready);
	DBG("Consumer management thread is ready");
}

/*
 * This thread manage the consumer error sent back to the session daemon.
 */
static void *thread_consumer_management(void *data)
{
	int sock = -1, i, ret, err = -1, should_quit = 0;
	uint32_t nb_fd;
	enum lttcomm_return_code code;
	struct lttng_poll_event events;
	struct thread_notifiers *notifiers = (thread_notifiers *) data;
	struct consumer_data *consumer_data = notifiers->consumer_data;
	const auto thread_quit_pipe_fd = lttng_pipe_get_readfd(notifiers->quit_pipe);
	struct consumer_socket *cmd_socket_wrapper = NULL;

	DBG("[thread] Manage consumer started");

	rcu_register_thread();
	rcu_thread_online();

	health_register(the_health_sessiond, HEALTH_SESSIOND_TYPE_CONSUMER);

	health_code_update();

	/*
	 * Pass 3 as size here for the thread quit pipe, consumerd_err_sock and the
	 * metadata_sock. Nothing more will be added to this poll set.
	 */
	ret = lttng_poll_create(&events, 3, LTTNG_CLOEXEC);
	if (ret < 0) {
		mark_thread_intialization_as_failed(notifiers);
		goto error_poll;
	}

	ret = lttng_poll_add(&events, thread_quit_pipe_fd, LPOLLIN);
	if (ret < 0) {
		mark_thread_intialization_as_failed(notifiers);
		goto error;
	}

	/*
	 * The error socket here is already in a listening state which was done
	 * just before spawning this thread to avoid a race between the consumer
	 * daemon exec trying to connect and the listen() call.
	 */
	ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
	if (ret < 0) {
		mark_thread_intialization_as_failed(notifiers);
		goto error;
	}

	health_code_update();

	/* Infinite blocking call, waiting for transmission */
	health_poll_entry();

	if (testpoint(sessiond_thread_manage_consumer)) {
		mark_thread_intialization_as_failed(notifiers);
		goto error;
	}

	ret = lttng_poll_wait(&events, -1);
	health_poll_exit();
	if (ret < 0) {
		mark_thread_intialization_as_failed(notifiers);
		goto error;
	}

	nb_fd = ret;

	for (i = 0; i < nb_fd; i++) {
		/* Fetch once the poll data */
		const auto revents = LTTNG_POLL_GETEV(&events, i);
		const auto pollfd = LTTNG_POLL_GETFD(&events, i);

		health_code_update();

		/* Activity on thread quit pipe, exiting. */
		if (pollfd == thread_quit_pipe_fd) {
			DBG("Activity on thread quit pipe");
			err = 0;
			mark_thread_intialization_as_failed(notifiers);
			goto exit;
		} else if (pollfd == consumer_data->err_sock) {
			/* Event on the registration socket */
			if (revents & LPOLLIN) {
				continue;
			} else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
				ERR("consumer err socket poll error");
				mark_thread_intialization_as_failed(notifiers);
				goto error;
			} else {
				ERR("Unexpected poll events %u for sock %d", revents, pollfd);
				mark_thread_intialization_as_failed(notifiers);
				goto error;
			}
		}
	}

	sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
	if (sock < 0) {
		mark_thread_intialization_as_failed(notifiers);
		goto error;
	}

	/*
	 * Set the CLOEXEC flag. Return code is useless because either way, the
	 * show must go on.
	 */
	(void) utils_set_fd_cloexec(sock);

	health_code_update();

	DBG2("Receiving code from consumer err_sock");

	/* Getting status code from kconsumerd */
	ret = lttcomm_recv_unix_sock(sock, &code,
			sizeof(enum lttcomm_return_code));
	if (ret <= 0) {
		mark_thread_intialization_as_failed(notifiers);
		goto error;
	}

	health_code_update();
	if (code != LTTCOMM_CONSUMERD_COMMAND_SOCK_READY) {
		ERR("consumer error when waiting for SOCK_READY : %s",
				lttcomm_get_readable_code((lttcomm_return_code) -code));
		mark_thread_intialization_as_failed(notifiers);
		goto error;
	}

	/* Connect both command and metadata sockets. */
	consumer_data->cmd_sock =
			lttcomm_connect_unix_sock(
				consumer_data->cmd_unix_sock_path);
	consumer_data->metadata_fd =
			lttcomm_connect_unix_sock(
				consumer_data->cmd_unix_sock_path);
	if (consumer_data->cmd_sock < 0 || consumer_data->metadata_fd < 0) {
		PERROR("consumer connect cmd socket");
		mark_thread_intialization_as_failed(notifiers);
		goto error;
	}

	consumer_data->metadata_sock.fd_ptr = &consumer_data->metadata_fd;

	/* Create metadata socket lock. */
	consumer_data->metadata_sock.lock = zmalloc<pthread_mutex_t>();
	if (consumer_data->metadata_sock.lock == NULL) {
		PERROR("zmalloc pthread mutex");
		mark_thread_intialization_as_failed(notifiers);
		goto error;
	}
	pthread_mutex_init(consumer_data->metadata_sock.lock, NULL);

	DBG("Consumer command socket ready (fd: %d)", consumer_data->cmd_sock);
	DBG("Consumer metadata socket ready (fd: %d)",
			consumer_data->metadata_fd);

	/*
	 * Remove the consumerd error sock since we've established a connection.
	 */
	ret = lttng_poll_del(&events, consumer_data->err_sock);
	if (ret < 0) {
		mark_thread_intialization_as_failed(notifiers);
		goto error;
	}

	/* Add new accepted error socket. */
	ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
	if (ret < 0) {
		mark_thread_intialization_as_failed(notifiers);
		goto error;
	}

	/* Add metadata socket that is successfully connected. */
	ret = lttng_poll_add(&events, consumer_data->metadata_fd,
			LPOLLIN | LPOLLRDHUP);
	if (ret < 0) {
		mark_thread_intialization_as_failed(notifiers);
		goto error;
	}

	health_code_update();

	/*
	 * Transfer the write-end of the channel monitoring pipe to the consumer
	 * by issuing a SET_CHANNEL_MONITOR_PIPE command.
	 */
	cmd_socket_wrapper = consumer_allocate_socket(&consumer_data->cmd_sock);
	if (!cmd_socket_wrapper) {
		mark_thread_intialization_as_failed(notifiers);
		goto error;
	}
	cmd_socket_wrapper->lock = &consumer_data->lock;

	pthread_mutex_lock(cmd_socket_wrapper->lock);
	ret = consumer_init(cmd_socket_wrapper, the_sessiond_uuid);
	if (ret) {
		ERR("Failed to send sessiond uuid to consumer daemon");
		mark_thread_intialization_as_failed(notifiers);
		pthread_mutex_unlock(cmd_socket_wrapper->lock);
		goto error;
	}
	pthread_mutex_unlock(cmd_socket_wrapper->lock);

	ret = consumer_send_channel_monitor_pipe(cmd_socket_wrapper,
			consumer_data->channel_monitor_pipe);
	if (ret) {
		mark_thread_intialization_as_failed(notifiers);
		goto error;
	}

	/* Discard the socket wrapper as it is no longer needed. */
	consumer_destroy_socket(cmd_socket_wrapper);
	cmd_socket_wrapper = NULL;

	/* The thread is completely initialized, signal that it is ready. */
	mark_thread_as_ready(notifiers);

	/* Infinite blocking call, waiting for transmission */
	while (1) {
		health_code_update();

		/* Exit the thread because the thread quit pipe has been triggered. */
		if (should_quit) {
			/* Not a health error. */
			err = 0;
			goto exit;
		}

		health_poll_entry();
		ret = lttng_poll_wait(&events, -1);
		health_poll_exit();
		if (ret < 0) {
			goto error;
		}

		nb_fd = ret;

		for (i = 0; i < nb_fd; i++) {
			/* Fetch once the poll data */
			const auto revents = LTTNG_POLL_GETEV(&events, i);
			const auto pollfd = LTTNG_POLL_GETFD(&events, i);

			health_code_update();

			/*
			 * Thread quit pipe has been triggered, flag that we should stop
			 * but continue the current loop to handle potential data from
			 * consumer.
			 */
			if (pollfd == thread_quit_pipe_fd) {
				should_quit = 1;
			} else if (pollfd == sock) {
				/* Event on the consumerd socket */
				if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)
						&& !(revents & LPOLLIN)) {
					ERR("consumer err socket second poll error");
					goto error;
				}
				health_code_update();
				/* Wait for any kconsumerd error */
				ret = lttcomm_recv_unix_sock(sock, &code,
						sizeof(enum lttcomm_return_code));
				if (ret <= 0) {
					ERR("consumer closed the command socket");
					goto error;
				}

				ERR("consumer return code : %s",
						lttcomm_get_readable_code((lttcomm_return_code) -code));

				goto exit;
			} else if (pollfd == consumer_data->metadata_fd) {
				if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)
						&& !(revents & LPOLLIN)) {
					ERR("consumer err metadata socket second poll error");
					goto error;
				}
				/* UST metadata requests */
				ret = ust_consumer_metadata_request(
						&consumer_data->metadata_sock);
				if (ret < 0) {
					ERR("Handling metadata request");
					goto error;
				}
			}
			/* No need for an else branch all FDs are tested prior. */
		}
		health_code_update();
	}

exit:
error:
	/*
	 * We lock here because we are about to close the sockets and some other
	 * thread might be using them so get exclusive access which will abort all
	 * other consumer command by other threads.
	 */
	pthread_mutex_lock(&consumer_data->lock);

	/* Immediately set the consumerd state to stopped */
	if (consumer_data->type == LTTNG_CONSUMER_KERNEL) {
		uatomic_set(&the_kernel_consumerd_state, CONSUMER_ERROR);
	} else if (consumer_data->type == LTTNG_CONSUMER64_UST ||
			consumer_data->type == LTTNG_CONSUMER32_UST) {
		uatomic_set(&the_ust_consumerd_state, CONSUMER_ERROR);
	} else {
		/* Code flow error... */
		abort();
	}

	if (consumer_data->err_sock >= 0) {
		ret = close(consumer_data->err_sock);
		if (ret) {
			PERROR("close");
		}
		consumer_data->err_sock = -1;
	}
	if (consumer_data->cmd_sock >= 0) {
		ret = close(consumer_data->cmd_sock);
		if (ret) {
			PERROR("close");
		}
		consumer_data->cmd_sock = -1;
	}
	if (consumer_data->metadata_sock.fd_ptr &&
	    *consumer_data->metadata_sock.fd_ptr >= 0) {
		ret = close(*consumer_data->metadata_sock.fd_ptr);
		if (ret) {
			PERROR("close");
		}
	}
	if (sock >= 0) {
		ret = close(sock);
		if (ret) {
			PERROR("close");
		}
	}

	unlink(consumer_data->err_unix_sock_path);
	unlink(consumer_data->cmd_unix_sock_path);
	pthread_mutex_unlock(&consumer_data->lock);

	/* Cleanup metadata socket mutex. */
	if (consumer_data->metadata_sock.lock) {
		pthread_mutex_destroy(consumer_data->metadata_sock.lock);
		free(consumer_data->metadata_sock.lock);
	}
	lttng_poll_clean(&events);

	if (cmd_socket_wrapper) {
		consumer_destroy_socket(cmd_socket_wrapper);
	}
error_poll:
	if (err) {
		health_error();
		ERR("Health error occurred in %s", __func__);
	}
	health_unregister(the_health_sessiond);
	DBG("consumer thread cleanup completed");

	rcu_thread_offline();
	rcu_unregister_thread();

	return NULL;
}

static bool shutdown_consumer_management_thread(void *data)
{
	struct thread_notifiers *notifiers = (thread_notifiers *) data;
	const int write_fd = lttng_pipe_get_writefd(notifiers->quit_pipe);

	return notify_thread_pipe(write_fd) == 1;
}

static void cleanup_consumer_management_thread(void *data)
{
	struct thread_notifiers *notifiers = (thread_notifiers *) data;

	lttng_pipe_destroy(notifiers->quit_pipe);
	free(notifiers);
}

bool launch_consumer_management_thread(struct consumer_data *consumer_data)
{
	struct lttng_pipe *quit_pipe;
	struct thread_notifiers *notifiers = NULL;
	struct lttng_thread *thread;

	notifiers = zmalloc<thread_notifiers>();
	if (!notifiers) {
		goto error_alloc;
	}

	quit_pipe = lttng_pipe_open(FD_CLOEXEC);
	if (!quit_pipe) {
		goto error;
	}
	notifiers->quit_pipe = quit_pipe;
	notifiers->consumer_data = consumer_data;
	sem_init(&notifiers->ready, 0, 0);

	thread = lttng_thread_create("Consumer management",
			thread_consumer_management,
			shutdown_consumer_management_thread,
			cleanup_consumer_management_thread,
			notifiers);
	if (!thread) {
		goto error;
	}
	wait_until_thread_is_ready(notifiers);
	lttng_thread_put(thread);
	if (notifiers->initialization_result) {
		return false;
	}
	return true;
error:
	cleanup_consumer_management_thread(notifiers);
error_alloc:
	return false;
}
Commit	Line	Data
4ec029ed	1	/*
21cf9b6b	2	* Copyright (C) 2011 EfficiOS Inc.
ab5be9fa MJ	3	* Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
ab5be9fa MJ	4	* Copyright (C) 2013 Jérémie Galarneau <jeremie.galarneau@efficios.com>
4ec029ed	5	*
ab5be9fa	6	* SPDX-License-Identifier: GPL-2.0-only
4ec029ed	7	*
4ec029ed JG	8	*/
	9
	10	#include <signal.h>
	11
c9e313bc SM	12	#include <common/pipe.hpp>
	13	#include <common/utils.hpp>
	14
	15	#include "manage-consumer.hpp"
	16	#include "testpoint.hpp"
	17	#include "health-sessiond.hpp"
	18	#include "utils.hpp"
	19	#include "thread.hpp"
	20	#include "ust-consumer.hpp"
4ec029ed	21
f1494934	22	namespace {
4ec029ed JG	23	struct thread_notifiers {
	24	struct lttng_pipe *quit_pipe;
	25	struct consumer_data *consumer_data;
52c50f8f	26	sem_t ready;
4ec029ed JG	27	int initialization_result;
4ec029ed JG	28	};
f1494934	29	} /* namespace */
4ec029ed JG	30
	31	static void mark_thread_as_ready(struct thread_notifiers *notifiers)
	32	{
	33	DBG("Marking consumer management thread as ready");
	34	notifiers->initialization_result = 0;
	35	sem_post(&notifiers->ready);
	36	}
	37
	38	static void mark_thread_intialization_as_failed(
	39	struct thread_notifiers *notifiers)
	40	{
52c50f8f	41	ERR("Consumer management thread entering error state");
4ec029ed JG	42	notifiers->initialization_result = -1;
	43	sem_post(&notifiers->ready);
	44	}
	45
	46	static void wait_until_thread_is_ready(struct thread_notifiers *notifiers)
	47	{
	48	DBG("Waiting for consumer management thread to be ready");
	49	sem_wait(&notifiers->ready);
	50	DBG("Consumer management thread is ready");
	51	}
	52
	53	/*
	54	* This thread manage the consumer error sent back to the session daemon.
	55	*/
0e0b3d3a	56	static void thread_consumer_management(void data)
4ec029ed	57	{
8a00688e MJ	58	int sock = -1, i, ret, err = -1, should_quit = 0;
8a00688e MJ	59	uint32_t nb_fd;
4ec029ed JG	60	enum lttcomm_return_code code;
4ec029ed JG	61	struct lttng_poll_event events;
7966af57	62	struct thread_notifiers notifiers = (thread_notifiers ) data;
4ec029ed	63	struct consumer_data *consumer_data = notifiers->consumer_data;
8a00688e	64	const auto thread_quit_pipe_fd = lttng_pipe_get_readfd(notifiers->quit_pipe);
4ec029ed JG	65	struct consumer_socket *cmd_socket_wrapper = NULL;
	66
	67	DBG("[thread] Manage consumer started");
	68
	69	rcu_register_thread();
	70	rcu_thread_online();
	71
412d7227	72	health_register(the_health_sessiond, HEALTH_SESSIOND_TYPE_CONSUMER);
4ec029ed JG	73
	74	health_code_update();
	75
	76	/*
	77	* Pass 3 as size here for the thread quit pipe, consumerd_err_sock and the
	78	* metadata_sock. Nothing more will be added to this poll set.
	79	*/
	80	ret = lttng_poll_create(&events, 3, LTTNG_CLOEXEC);
	81	if (ret < 0) {
	82	mark_thread_intialization_as_failed(notifiers);
	83	goto error_poll;
	84	}
	85
1524f98c	86	ret = lttng_poll_add(&events, thread_quit_pipe_fd, LPOLLIN);
4ec029ed JG	87	if (ret < 0) {
	88	mark_thread_intialization_as_failed(notifiers);
	89	goto error;
	90	}
	91
	92	/*
	93	* The error socket here is already in a listening state which was done
	94	* just before spawning this thread to avoid a race between the consumer
	95	* daemon exec trying to connect and the listen() call.
	96	*/
	97	ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN \| LPOLLRDHUP);
	98	if (ret < 0) {
	99	mark_thread_intialization_as_failed(notifiers);
	100	goto error;
	101	}
	102
	103	health_code_update();
	104
	105	/* Infinite blocking call, waiting for transmission */
	106	health_poll_entry();
	107
	108	if (testpoint(sessiond_thread_manage_consumer)) {
	109	mark_thread_intialization_as_failed(notifiers);
	110	goto error;
	111	}
	112
	113	ret = lttng_poll_wait(&events, -1);
	114	health_poll_exit();
	115	if (ret < 0) {
	116	mark_thread_intialization_as_failed(notifiers);
	117	goto error;
	118	}
	119
	120	nb_fd = ret;
	121
	122	for (i = 0; i < nb_fd; i++) {
	123	/* Fetch once the poll data */
8a00688e MJ	124	const auto revents = LTTNG_POLL_GETEV(&events, i);
8a00688e MJ	125	const auto pollfd = LTTNG_POLL_GETFD(&events, i);
4ec029ed JG	126
	127	health_code_update();
	128
8a00688e MJ	129	/* Activity on thread quit pipe, exiting. */
	130	if (pollfd == thread_quit_pipe_fd) {
	131	DBG("Activity on thread quit pipe");
4ec029ed JG	132	err = 0;
	133	mark_thread_intialization_as_failed(notifiers);
	134	goto exit;
	135	} else if (pollfd == consumer_data->err_sock) {
	136	/* Event on the registration socket */
	137	if (revents & LPOLLIN) {
	138	continue;
	139	} else if (revents & (LPOLLERR \| LPOLLHUP \| LPOLLRDHUP)) {
	140	ERR("consumer err socket poll error");
	141	mark_thread_intialization_as_failed(notifiers);
	142	goto error;
	143	} else {
	144	ERR("Unexpected poll events %u for sock %d", revents, pollfd);
	145	mark_thread_intialization_as_failed(notifiers);
	146	goto error;
	147	}
	148	}
	149	}
	150
	151	sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
	152	if (sock < 0) {
	153	mark_thread_intialization_as_failed(notifiers);
	154	goto error;
	155	}
	156
	157	/*
	158	* Set the CLOEXEC flag. Return code is useless because either way, the
	159	* show must go on.
	160	*/
	161	(void) utils_set_fd_cloexec(sock);
	162
	163	health_code_update();
	164
	165	DBG2("Receiving code from consumer err_sock");
	166
	167	/* Getting status code from kconsumerd */
	168	ret = lttcomm_recv_unix_sock(sock, &code,
	169	sizeof(enum lttcomm_return_code));
	170	if (ret <= 0) {
	171	mark_thread_intialization_as_failed(notifiers);
	172	goto error;
	173	}
	174
	175	health_code_update();
	176	if (code != LTTCOMM_CONSUMERD_COMMAND_SOCK_READY) {
	177	ERR("consumer error when waiting for SOCK_READY : %s",
7966af57	178	lttcomm_get_readable_code((lttcomm_return_code) -code));
4ec029ed JG	179	mark_thread_intialization_as_failed(notifiers);
	180	goto error;
	181	}
	182
	183	/* Connect both command and metadata sockets. */
	184	consumer_data->cmd_sock =
	185	lttcomm_connect_unix_sock(
	186	consumer_data->cmd_unix_sock_path);
	187	consumer_data->metadata_fd =
	188	lttcomm_connect_unix_sock(
	189	consumer_data->cmd_unix_sock_path);
	190	if (consumer_data->cmd_sock < 0 \|\| consumer_data->metadata_fd < 0) {
	191	PERROR("consumer connect cmd socket");
	192	mark_thread_intialization_as_failed(notifiers);
	193	goto error;
	194	}
	195
	196	consumer_data->metadata_sock.fd_ptr = &consumer_data->metadata_fd;
	197
	198	/* Create metadata socket lock. */
64803277	199	consumer_data->metadata_sock.lock = zmalloc<pthread_mutex_t>();
4ec029ed JG	200	if (consumer_data->metadata_sock.lock == NULL) {
	201	PERROR("zmalloc pthread mutex");
	202	mark_thread_intialization_as_failed(notifiers);
	203	goto error;
	204	}
	205	pthread_mutex_init(consumer_data->metadata_sock.lock, NULL);
	206
	207	DBG("Consumer command socket ready (fd: %d)", consumer_data->cmd_sock);
	208	DBG("Consumer metadata socket ready (fd: %d)",
	209	consumer_data->metadata_fd);
	210
	211	/*
	212	* Remove the consumerd error sock since we've established a connection.
	213	*/
	214	ret = lttng_poll_del(&events, consumer_data->err_sock);
	215	if (ret < 0) {
	216	mark_thread_intialization_as_failed(notifiers);
	217	goto error;
	218	}
	219
	220	/* Add new accepted error socket. */
	221	ret = lttng_poll_add(&events, sock, LPOLLIN \| LPOLLRDHUP);
	222	if (ret < 0) {
	223	mark_thread_intialization_as_failed(notifiers);
	224	goto error;
	225	}
	226
	227	/* Add metadata socket that is successfully connected. */
	228	ret = lttng_poll_add(&events, consumer_data->metadata_fd,
	229	LPOLLIN \| LPOLLRDHUP);
	230	if (ret < 0) {
	231	mark_thread_intialization_as_failed(notifiers);
	232	goto error;
	233	}
	234
	235	health_code_update();
	236
	237	/*
09ede842 JG	238	* Transfer the write-end of the channel monitoring pipe to the consumer
09ede842 JG	239	* by issuing a SET_CHANNEL_MONITOR_PIPE command.
4ec029ed JG	240	*/
	241	cmd_socket_wrapper = consumer_allocate_socket(&consumer_data->cmd_sock);
	242	if (!cmd_socket_wrapper) {
	243	mark_thread_intialization_as_failed(notifiers);
	244	goto error;
	245	}
	246	cmd_socket_wrapper->lock = &consumer_data->lock;
	247
09ede842	248	pthread_mutex_lock(cmd_socket_wrapper->lock);
412d7227	249	ret = consumer_init(cmd_socket_wrapper, the_sessiond_uuid);
09ede842 JG	250	if (ret) {
	251	ERR("Failed to send sessiond uuid to consumer daemon");
	252	mark_thread_intialization_as_failed(notifiers);
	253	pthread_mutex_unlock(cmd_socket_wrapper->lock);
	254	goto error;
	255	}
	256	pthread_mutex_unlock(cmd_socket_wrapper->lock);
	257
4ec029ed JG	258	ret = consumer_send_channel_monitor_pipe(cmd_socket_wrapper,
	259	consumer_data->channel_monitor_pipe);
	260	if (ret) {
	261	mark_thread_intialization_as_failed(notifiers);
	262	goto error;
	263	}
	264
	265	/* Discard the socket wrapper as it is no longer needed. */
	266	consumer_destroy_socket(cmd_socket_wrapper);
	267	cmd_socket_wrapper = NULL;
	268
	269	/* The thread is completely initialized, signal that it is ready. */
	270	mark_thread_as_ready(notifiers);
	271
	272	/* Infinite blocking call, waiting for transmission */
	273	while (1) {
	274	health_code_update();
	275
	276	/* Exit the thread because the thread quit pipe has been triggered. */
	277	if (should_quit) {
	278	/* Not a health error. */
	279	err = 0;
	280	goto exit;
	281	}
	282
	283	health_poll_entry();
	284	ret = lttng_poll_wait(&events, -1);
	285	health_poll_exit();
	286	if (ret < 0) {
	287	goto error;
	288	}
	289
	290	nb_fd = ret;
	291
	292	for (i = 0; i < nb_fd; i++) {
	293	/* Fetch once the poll data */
8a00688e MJ	294	const auto revents = LTTNG_POLL_GETEV(&events, i);
8a00688e MJ	295	const auto pollfd = LTTNG_POLL_GETFD(&events, i);
4ec029ed JG	296
	297	health_code_update();
	298
4ec029ed JG	299	/*
	300	* Thread quit pipe has been triggered, flag that we should stop
	301	* but continue the current loop to handle potential data from
	302	* consumer.
	303	*/
8a00688e	304	if (pollfd == thread_quit_pipe_fd) {
4ec029ed JG	305	should_quit = 1;
	306	} else if (pollfd == sock) {
	307	/* Event on the consumerd socket */
	308	if (revents & (LPOLLERR \| LPOLLHUP \| LPOLLRDHUP)
	309	&& !(revents & LPOLLIN)) {
	310	ERR("consumer err socket second poll error");
	311	goto error;
	312	}
	313	health_code_update();
	314	/* Wait for any kconsumerd error */
	315	ret = lttcomm_recv_unix_sock(sock, &code,
	316	sizeof(enum lttcomm_return_code));
	317	if (ret <= 0) {
	318	ERR("consumer closed the command socket");
	319	goto error;
	320	}
	321
	322	ERR("consumer return code : %s",
7966af57	323	lttcomm_get_readable_code((lttcomm_return_code) -code));
4ec029ed JG	324
	325	goto exit;
	326	} else if (pollfd == consumer_data->metadata_fd) {
	327	if (revents & (LPOLLERR \| LPOLLHUP \| LPOLLRDHUP)
	328	&& !(revents & LPOLLIN)) {
	329	ERR("consumer err metadata socket second poll error");
	330	goto error;
	331	}
	332	/* UST metadata requests */
	333	ret = ust_consumer_metadata_request(
	334	&consumer_data->metadata_sock);
	335	if (ret < 0) {
	336	ERR("Handling metadata request");
	337	goto error;
	338	}
	339	}
	340	/* No need for an else branch all FDs are tested prior. */
	341	}
	342	health_code_update();
	343	}
	344
	345	exit:
	346	error:
	347	/*
	348	* We lock here because we are about to close the sockets and some other
	349	* thread might be using them so get exclusive access which will abort all
	350	* other consumer command by other threads.
	351	*/
	352	pthread_mutex_lock(&consumer_data->lock);
	353
	354	/* Immediately set the consumerd state to stopped */
	355	if (consumer_data->type == LTTNG_CONSUMER_KERNEL) {
412d7227	356	uatomic_set(&the_kernel_consumerd_state, CONSUMER_ERROR);
4ec029ed JG	357	} else if (consumer_data->type == LTTNG_CONSUMER64_UST \|\|
4ec029ed JG	358	consumer_data->type == LTTNG_CONSUMER32_UST) {
412d7227	359	uatomic_set(&the_ust_consumerd_state, CONSUMER_ERROR);
4ec029ed JG	360	} else {
4ec029ed JG	361	/* Code flow error... */
a0377dfe	362	abort();
4ec029ed JG	363	}
	364
	365	if (consumer_data->err_sock >= 0) {
	366	ret = close(consumer_data->err_sock);
	367	if (ret) {
	368	PERROR("close");
	369	}
	370	consumer_data->err_sock = -1;
	371	}
	372	if (consumer_data->cmd_sock >= 0) {
	373	ret = close(consumer_data->cmd_sock);
	374	if (ret) {
	375	PERROR("close");
	376	}
	377	consumer_data->cmd_sock = -1;
	378	}
	379	if (consumer_data->metadata_sock.fd_ptr &&
	380	*consumer_data->metadata_sock.fd_ptr >= 0) {
	381	ret = close(*consumer_data->metadata_sock.fd_ptr);
	382	if (ret) {
	383	PERROR("close");
	384	}
	385	}
	386	if (sock >= 0) {
	387	ret = close(sock);
	388	if (ret) {
	389	PERROR("close");
	390	}
	391	}
	392
	393	unlink(consumer_data->err_unix_sock_path);
	394	unlink(consumer_data->cmd_unix_sock_path);
	395	pthread_mutex_unlock(&consumer_data->lock);
	396
	397	/* Cleanup metadata socket mutex. */
	398	if (consumer_data->metadata_sock.lock) {
	399	pthread_mutex_destroy(consumer_data->metadata_sock.lock);
	400	free(consumer_data->metadata_sock.lock);
	401	}
	402	lttng_poll_clean(&events);
	403
	404	if (cmd_socket_wrapper) {
	405	consumer_destroy_socket(cmd_socket_wrapper);
	406	}
	407	error_poll:
	408	if (err) {
	409	health_error();
	410	ERR("Health error occurred in %s", __func__);
	411	}
412d7227	412	health_unregister(the_health_sessiond);
4ec029ed JG	413	DBG("consumer thread cleanup completed");
	414
	415	rcu_thread_offline();
	416	rcu_unregister_thread();
	417
	418	return NULL;
	419	}
	420
	421	static bool shutdown_consumer_management_thread(void *data)
	422	{
7966af57	423	struct thread_notifiers notifiers = (thread_notifiers ) data;
4ec029ed JG	424	const int write_fd = lttng_pipe_get_writefd(notifiers->quit_pipe);
	425
	426	return notify_thread_pipe(write_fd) == 1;
	427	}
	428
	429	static void cleanup_consumer_management_thread(void *data)
	430	{
7966af57	431	struct thread_notifiers notifiers = (thread_notifiers ) data;
4ec029ed JG	432
	433	lttng_pipe_destroy(notifiers->quit_pipe);
	434	free(notifiers);
	435	}
	436
	437	bool launch_consumer_management_thread(struct consumer_data *consumer_data)
	438	{
	439	struct lttng_pipe *quit_pipe;
	440	struct thread_notifiers *notifiers = NULL;
	441	struct lttng_thread *thread;
	442
64803277	443	notifiers = zmalloc<thread_notifiers>();
4ec029ed	444	if (!notifiers) {
21fa020e JG	445	goto error_alloc;
	446	}
	447
	448	quit_pipe = lttng_pipe_open(FD_CLOEXEC);
	449	if (!quit_pipe) {
4ec029ed JG	450	goto error;
	451	}
	452	notifiers->quit_pipe = quit_pipe;
	453	notifiers->consumer_data = consumer_data;
	454	sem_init(&notifiers->ready, 0, 0);
	455
	456	thread = lttng_thread_create("Consumer management",
	457	thread_consumer_management,
	458	shutdown_consumer_management_thread,
	459	cleanup_consumer_management_thread,
	460	notifiers);
	461	if (!thread) {
	462	goto error;
	463	}
	464	wait_until_thread_is_ready(notifiers);
	465	lttng_thread_put(thread);
	466	if (notifiers->initialization_result) {
bd3739b0	467	return false;
4ec029ed JG	468	}
	469	return true;
	470	error:
	471	cleanup_consumer_management_thread(notifiers);
21fa020e	472	error_alloc:
4ec029ed JG	473	return false;
4ec029ed JG	474	}