[lttng-tools.git] / src / bin / lttng-consumerd / health-consumerd.c

/*
 * Copyright (C) 2013 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2 only,
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#define _LGPL_SOURCE
#include <fcntl.h>
#include <getopt.h>
#include <grp.h>
#include <limits.h>
#include <pthread.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ipc.h>
#include <sys/resource.h>
#include <sys/shm.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <urcu/list.h>
#include <poll.h>
#include <unistd.h>
#include <sys/mman.h>
#include <assert.h>
#include <urcu/compiler.h>
#include <ulimit.h>
#include <inttypes.h>

#include <common/defaults.h>
#include <common/common.h>
#include <common/consumer/consumer.h>
#include <common/consumer/consumer-timer.h>
#include <common/compat/poll.h>
#include <common/sessiond-comm/sessiond-comm.h>
#include <common/utils.h>

#include "lttng-consumerd.h"
#include "health-consumerd.h"

/* Global health check unix path */
static char health_unix_sock_path[PATH_MAX];

int health_quit_pipe[2];

/*
 * Check if the thread quit pipe was triggered.
 *
 * Return 1 if it was triggered else 0;
 */
static
int check_health_quit_pipe(int fd, uint32_t events)
{
	if (fd == health_quit_pipe[0] && (events & LPOLLIN)) {
		return 1;
	}

	return 0;
}

/*
 * Send data on a unix socket using the liblttsessiondcomm API.
 *
 * Return lttcomm error code.
 */
static int send_unix_sock(int sock, void *buf, size_t len)
{
	/* Check valid length */
	if (len == 0) {
		return -1;
	}

	return lttcomm_send_unix_sock(sock, buf, len);
}

static
int setup_health_path(void)
{
	int is_root, ret = 0;
	enum lttng_consumer_type type;
	const char *home_path;

	type = lttng_consumer_get_type();
	is_root = !getuid();

	if (is_root) {
		if (strlen(health_unix_sock_path) != 0) {
			goto end;
		}
		switch (type) {
		case LTTNG_CONSUMER_KERNEL:
			snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
				DEFAULT_GLOBAL_KCONSUMER_HEALTH_UNIX_SOCK);
			break;
		case LTTNG_CONSUMER64_UST:
			snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
				DEFAULT_GLOBAL_USTCONSUMER64_HEALTH_UNIX_SOCK);
			break;
		case LTTNG_CONSUMER32_UST:
			snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
				DEFAULT_GLOBAL_USTCONSUMER32_HEALTH_UNIX_SOCK);
			break;
		default:
			ret = -EINVAL;
			goto end;
		}
	} else {
		home_path = utils_get_home_dir();
		if (home_path == NULL) {
			/* TODO: Add --socket PATH option */
			ERR("Can't get HOME directory for sockets creation.");
			ret = -EPERM;
			goto end;
		}

		/* Set health check Unix path */
		if (strlen(health_unix_sock_path) != 0) {
			goto end;
		}
		switch (type) {
		case LTTNG_CONSUMER_KERNEL:
			snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
				DEFAULT_HOME_KCONSUMER_HEALTH_UNIX_SOCK, home_path);
			break;
		case LTTNG_CONSUMER64_UST:
			snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
				DEFAULT_HOME_USTCONSUMER64_HEALTH_UNIX_SOCK, home_path);
			break;
		case LTTNG_CONSUMER32_UST:
			snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
				DEFAULT_HOME_USTCONSUMER32_HEALTH_UNIX_SOCK, home_path);
			break;
		default:
			ret = -EINVAL;
			goto end;
		}
	}
end:
	return ret;
}

/*
 * Thread managing health check socket.
 */
void *thread_manage_health(void *data)
{
	int sock = -1, new_sock = -1, ret, i, pollfd, err = -1;
	uint32_t revents, nb_fd;
	struct lttng_poll_event events;
	struct health_comm_msg msg;
	struct health_comm_reply reply;
	int is_root;

	DBG("[thread] Manage health check started");

	setup_health_path();

	rcu_register_thread();

	/* We might hit an error path before this is created. */
	lttng_poll_init(&events);

	/* Create unix socket */
	sock = lttcomm_create_unix_sock(health_unix_sock_path);
	if (sock < 0) {
		ERR("Unable to create health check Unix socket");
		err = -1;
		goto error;
	}

	is_root = !getuid();
	if (is_root) {
		/* lttng health client socket path permissions */
		gid_t gid;

		ret = utils_get_group_id(tracing_group_name, true, &gid);
		if (ret) {
			/* Default to root group. */
			gid = 0;
		}

		ret = chown(health_unix_sock_path, 0, gid);
		if (ret < 0) {
			ERR("Unable to set group on %s", health_unix_sock_path);
			PERROR("chown");
			err = -1;
			goto error;
		}

		ret = chmod(health_unix_sock_path,
				S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
		if (ret < 0) {
			ERR("Unable to set permissions on %s", health_unix_sock_path);
			PERROR("chmod");
			err = -1;
			goto error;
		}
	}

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

	ret = lttcomm_listen_unix_sock(sock);
	if (ret < 0) {
		goto error;
	}

	/* Size is set to 1 for the consumer_channel pipe */
	ret = lttng_poll_create(&events, 2, LTTNG_CLOEXEC);
	if (ret < 0) {
		ERR("Poll set creation failed");
		goto error;
	}

	ret = lttng_poll_add(&events, health_quit_pipe[0], LPOLLIN);
	if (ret < 0) {
		goto error;
	}

	/* Add the application registration socket */
	ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLPRI);
	if (ret < 0) {
		goto error;
	}

	/* Perform prior memory accesses before decrementing ready */
	cmm_smp_mb__before_uatomic_dec();
	uatomic_dec(&lttng_consumer_ready);

	while (1) {
		DBG("Health check ready");

		/* Inifinite blocking call, waiting for transmission */
restart:
		ret = lttng_poll_wait(&events, -1);
		if (ret < 0) {
			/*
			 * Restart interrupted system call.
			 */
			if (errno == EINTR) {
				goto restart;
			}
			goto error;
		}

		nb_fd = ret;

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

			/* Thread quit pipe has been closed. Killing thread. */
			ret = check_health_quit_pipe(pollfd, revents);
			if (ret) {
				err = 0;
				goto exit;
			}

			/* Event on the registration socket */
			if (pollfd == sock) {
				if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)
						&& !(revents & LPOLLIN)) {
					ERR("Health socket poll error");
					goto error;
				}
			}
		}

		new_sock = lttcomm_accept_unix_sock(sock);
		if (new_sock < 0) {
			goto error;
		}

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

		DBG("Receiving data from client for health...");
		ret = lttcomm_recv_unix_sock(new_sock, (void *)&msg, sizeof(msg));
		if (ret <= 0) {
			DBG("Nothing recv() from client... continuing");
			ret = close(new_sock);
			if (ret) {
				PERROR("close");
			}
			new_sock = -1;
			continue;
		}

		rcu_thread_online();

		assert(msg.cmd == HEALTH_CMD_CHECK);

		memset(&reply, 0, sizeof(reply));
		for (i = 0; i < NR_HEALTH_CONSUMERD_TYPES; i++) {
			/*
			 * health_check_state return 0 if thread is in
			 * error.
			 */
			if (!health_check_state(health_consumerd, i)) {
				reply.ret_code |= 1ULL << i;
			}
		}

		DBG("Health check return value %" PRIx64, reply.ret_code);

		ret = send_unix_sock(new_sock, (void *) &reply, sizeof(reply));
		if (ret < 0) {
			ERR("Failed to send health data back to client");
		}

		/* End of transmission */
		ret = close(new_sock);
		if (ret) {
			PERROR("close");
		}
		new_sock = -1;
	}

exit:
error:
	if (err) {
		ERR("Health error occurred in %s", __func__);
	}
	DBG("Health check thread dying");
	unlink(health_unix_sock_path);
	if (sock >= 0) {
		ret = close(sock);
		if (ret) {
			PERROR("close");
		}
	}

	lttng_poll_clean(&events);

	rcu_unregister_thread();
	return NULL;
}
Commit	Line	Data
5c635c72 MD	1	/*
	2	* Copyright (C) 2013 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License, version 2 only,
	6	* as published by the Free Software Foundation.
	7	*
	8	* This program is distributed in the hope that it will be useful,
	9	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	11	* GNU General Public License for more details.
	12	*
	13	* You should have received a copy of the GNU General Public License along
	14	* with this program; if not, write to the Free Software Foundation, Inc.,
	15	* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
	16	*/
	17
6c1c0768	18	#define _LGPL_SOURCE
5c635c72 MD	19	#include <fcntl.h>
	20	#include <getopt.h>
	21	#include <grp.h>
	22	#include <limits.h>
	23	#include <pthread.h>
	24	#include <signal.h>
	25	#include <stdio.h>
	26	#include <stdlib.h>
	27	#include <string.h>
	28	#include <sys/ipc.h>
	29	#include <sys/resource.h>
	30	#include <sys/shm.h>
	31	#include <sys/socket.h>
	32	#include <sys/stat.h>
	33	#include <sys/types.h>
	34	#include <urcu/list.h>
	35	#include <poll.h>
	36	#include <unistd.h>
	37	#include <sys/mman.h>
	38	#include <assert.h>
5c635c72 MD	39	#include <urcu/compiler.h>
5c635c72 MD	40	#include <ulimit.h>
6c71277b	41	#include <inttypes.h>
5c635c72 MD	42
	43	#include <common/defaults.h>
	44	#include <common/common.h>
c8fea79c JR	45	#include <common/consumer/consumer.h>
c8fea79c JR	46	#include <common/consumer/consumer-timer.h>
5c635c72 MD	47	#include <common/compat/poll.h>
	48	#include <common/sessiond-comm/sessiond-comm.h>
	49	#include <common/utils.h>
	50
	51	#include "lttng-consumerd.h"
	52	#include "health-consumerd.h"
	53
	54	/* Global health check unix path */
	55	static char health_unix_sock_path[PATH_MAX];
	56
	57	int health_quit_pipe[2];
	58
	59	/*
	60	* Check if the thread quit pipe was triggered.
	61	*
	62	* Return 1 if it was triggered else 0;
	63	*/
	64	static
	65	int check_health_quit_pipe(int fd, uint32_t events)
	66	{
	67	if (fd == health_quit_pipe[0] && (events & LPOLLIN)) {
	68	return 1;
	69	}
	70
	71	return 0;
	72	}
	73
	74	/*
	75	* Send data on a unix socket using the liblttsessiondcomm API.
	76	*
	77	* Return lttcomm error code.
	78	*/
	79	static int send_unix_sock(int sock, void *buf, size_t len)
	80	{
	81	/* Check valid length */
	82	if (len == 0) {
	83	return -1;
	84	}
	85
	86	return lttcomm_send_unix_sock(sock, buf, len);
	87	}
	88
	89	static
	90	int setup_health_path(void)
	91	{
	92	int is_root, ret = 0;
	93	enum lttng_consumer_type type;
	94	const char *home_path;
	95
	96	type = lttng_consumer_get_type();
	97	is_root = !getuid();
	98
	99	if (is_root) {
	100	if (strlen(health_unix_sock_path) != 0) {
	101	goto end;
	102	}
	103	switch (type) {
	104	case LTTNG_CONSUMER_KERNEL:
	105	snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
	106	DEFAULT_GLOBAL_KCONSUMER_HEALTH_UNIX_SOCK);
	107	break;
	108	case LTTNG_CONSUMER64_UST:
	109	snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
	110	DEFAULT_GLOBAL_USTCONSUMER64_HEALTH_UNIX_SOCK);
111	break;
112	case LTTNG_CONSUMER32_UST:
113	snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
114	DEFAULT_GLOBAL_USTCONSUMER32_HEALTH_UNIX_SOCK);
115	break;
116	default:
117	ret = -EINVAL;
118	goto end;
119	}
120	} else {
5c635c72 MD	121	home_path = utils_get_home_dir();
	122	if (home_path == NULL) {
	123	/* TODO: Add --socket PATH option */
	124	ERR("Can't get HOME directory for sockets creation.");
	125	ret = -EPERM;
	126	goto end;
	127	}
	128
5c635c72 MD	129	/* Set health check Unix path */
	130	if (strlen(health_unix_sock_path) != 0) {
	131	goto end;
	132	}
	133	switch (type) {
	134	case LTTNG_CONSUMER_KERNEL:
	135	snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
dbc8403d	136	DEFAULT_HOME_KCONSUMER_HEALTH_UNIX_SOCK, home_path);
5c635c72 MD	137	break;
	138	case LTTNG_CONSUMER64_UST:
	139	snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
dbc8403d	140	DEFAULT_HOME_USTCONSUMER64_HEALTH_UNIX_SOCK, home_path);
5c635c72 MD	141	break;
	142	case LTTNG_CONSUMER32_UST:
	143	snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
dbc8403d	144	DEFAULT_HOME_USTCONSUMER32_HEALTH_UNIX_SOCK, home_path);
5c635c72 MD	145	break;
	146	default:
	147	ret = -EINVAL;
	148	goto end;
	149	}
	150	}
5c635c72 MD	151	end:
	152	return ret;
	153	}
	154
	155	/*
	156	* Thread managing health check socket.
	157	*/
	158	void thread_manage_health(void data)
	159	{
	160	int sock = -1, new_sock = -1, ret, i, pollfd, err = -1;
	161	uint32_t revents, nb_fd;
	162	struct lttng_poll_event events;
	163	struct health_comm_msg msg;
	164	struct health_comm_reply reply;
6c71277b	165	int is_root;
5c635c72 MD	166
	167	DBG("[thread] Manage health check started");
	168
	169	setup_health_path();
	170
	171	rcu_register_thread();
	172
	173	/* We might hit an error path before this is created. */
	174	lttng_poll_init(&events);
	175
	176	/* Create unix socket */
	177	sock = lttcomm_create_unix_sock(health_unix_sock_path);
	178	if (sock < 0) {
	179	ERR("Unable to create health check Unix socket");
67fe4075	180	err = -1;
5c635c72 MD	181	goto error;
	182	}
	183
6c71277b MD	184	is_root = !getuid();
	185	if (is_root) {
	186	/* lttng health client socket path permissions */
28ab59d0 JR	187	gid_t gid;
	188
	189	ret = utils_get_group_id(tracing_group_name, true, &gid);
	190	if (ret) {
	191	/* Default to root group. */
	192	gid = 0;
	193	}
	194
	195	ret = chown(health_unix_sock_path, 0, gid);
6c71277b MD	196	if (ret < 0) {
	197	ERR("Unable to set group on %s", health_unix_sock_path);
	198	PERROR("chown");
67fe4075	199	err = -1;
6c71277b MD	200	goto error;
	201	}
	202
	203	ret = chmod(health_unix_sock_path,
	204	S_IRUSR \| S_IWUSR \| S_IRGRP \| S_IWGRP);
	205	if (ret < 0) {
	206	ERR("Unable to set permissions on %s", health_unix_sock_path);
	207	PERROR("chmod");
67fe4075	208	err = -1;
6c71277b MD	209	goto error;
	210	}
	211	}
	212
5c635c72 MD	213	/*
	214	* Set the CLOEXEC flag. Return code is useless because either way, the
	215	* show must go on.
	216	*/
	217	(void) utils_set_fd_cloexec(sock);
	218
	219	ret = lttcomm_listen_unix_sock(sock);
	220	if (ret < 0) {
	221	goto error;
	222	}
	223
	224	/* Size is set to 1 for the consumer_channel pipe */
	225	ret = lttng_poll_create(&events, 2, LTTNG_CLOEXEC);
	226	if (ret < 0) {
	227	ERR("Poll set creation failed");
	228	goto error;
	229	}
	230
	231	ret = lttng_poll_add(&events, health_quit_pipe[0], LPOLLIN);
	232	if (ret < 0) {
	233	goto error;
	234	}
	235
	236	/* Add the application registration socket */
	237	ret = lttng_poll_add(&events, sock, LPOLLIN \| LPOLLPRI);
	238	if (ret < 0) {
	239	goto error;
	240	}
	241
748b7b07 MD	242	/* Perform prior memory accesses before decrementing ready */
	243	cmm_smp_mb__before_uatomic_dec();
	244	uatomic_dec(&lttng_consumer_ready);
	245
5c635c72 MD	246	while (1) {
	247	DBG("Health check ready");
	248
	249	/* Inifinite blocking call, waiting for transmission */
	250	restart:
	251	ret = lttng_poll_wait(&events, -1);
	252	if (ret < 0) {
	253	/*
	254	* Restart interrupted system call.
	255	*/
	256	if (errno == EINTR) {
	257	goto restart;
	258	}
	259	goto error;
	260	}
	261
	262	nb_fd = ret;
	263
	264	for (i = 0; i < nb_fd; i++) {
	265	/* Fetch once the poll data */
	266	revents = LTTNG_POLL_GETEV(&events, i);
	267	pollfd = LTTNG_POLL_GETFD(&events, i);
	268
	269	/* Thread quit pipe has been closed. Killing thread. */
	270	ret = check_health_quit_pipe(pollfd, revents);
	271	if (ret) {
	272	err = 0;
	273	goto exit;
	274	}
	275
	276	/* Event on the registration socket */
	277	if (pollfd == sock) {
03e43155 MD	278	if (revents & (LPOLLERR \| LPOLLHUP \| LPOLLRDHUP)
03e43155 MD	279	&& !(revents & LPOLLIN)) {
5c635c72 MD	280	ERR("Health socket poll error");
	281	goto error;
	282	}
	283	}
	284	}
	285
	286	new_sock = lttcomm_accept_unix_sock(sock);
	287	if (new_sock < 0) {
	288	goto error;
	289	}
	290
	291	/*
	292	* Set the CLOEXEC flag. Return code is useless because either way, the
	293	* show must go on.
	294	*/
	295	(void) utils_set_fd_cloexec(new_sock);
	296
	297	DBG("Receiving data from client for health...");
	298	ret = lttcomm_recv_unix_sock(new_sock, (void *)&msg, sizeof(msg));
	299	if (ret <= 0) {
	300	DBG("Nothing recv() from client... continuing");
	301	ret = close(new_sock);
	302	if (ret) {
	303	PERROR("close");
	304	}
	305	new_sock = -1;
	306	continue;
	307	}
	308
	309	rcu_thread_online();
	310
	311	assert(msg.cmd == HEALTH_CMD_CHECK);
	312
53efb85a	313	memset(&reply, 0, sizeof(reply));
6c71277b MD	314	for (i = 0; i < NR_HEALTH_CONSUMERD_TYPES; i++) {
	315	/*
	316	* health_check_state return 0 if thread is in
	317	* error.
	318	*/
	319	if (!health_check_state(health_consumerd, i)) {
	320	reply.ret_code \|= 1ULL << i;
	321	}
5c635c72 MD	322	}
5c635c72 MD	323
6137f630	324	DBG("Health check return value %" PRIx64, reply.ret_code);
5c635c72 MD	325
	326	ret = send_unix_sock(new_sock, (void *) &reply, sizeof(reply));
	327	if (ret < 0) {
	328	ERR("Failed to send health data back to client");
	329	}
	330
	331	/* End of transmission */
	332	ret = close(new_sock);
	333	if (ret) {
	334	PERROR("close");
	335	}
	336	new_sock = -1;
	337	}
	338
	339	exit:
	340	error:
	341	if (err) {
	342	ERR("Health error occurred in %s", __func__);
	343	}
	344	DBG("Health check thread dying");
	345	unlink(health_unix_sock_path);
	346	if (sock >= 0) {
	347	ret = close(sock);
	348	if (ret) {
	349	PERROR("close");
	350	}
	351	}
	352
	353	lttng_poll_clean(&events);
	354
	355	rcu_unregister_thread();
	356	return NULL;
	357	}