[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 _GNU_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 <config.h>
#include <urcu/compiler.h>
#include <ulimit.h>
#include <inttypes.h>

#include <common/defaults.h>
#include <common/common.h>
#include <common/consumer.h>
#include <common/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 {
		static char *rundir;

		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;
		}

		/*
		 * Create rundir from home path. This will create something like
		 * $HOME/.lttng
		 */
		ret = asprintf(&rundir, DEFAULT_LTTNG_HOME_RUNDIR, home_path);
		if (ret < 0) {
			ret = -ENOMEM;
			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, rundir);
			break;
		case LTTNG_CONSUMER64_UST:
			snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
				DEFAULT_HOME_USTCONSUMER64_HEALTH_UNIX_SOCK, rundir);
			break;
		case LTTNG_CONSUMER32_UST:
			snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
				DEFAULT_HOME_USTCONSUMER32_HEALTH_UNIX_SOCK, rundir);
			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");
		ret = -1;
		goto error;
	}

	is_root = !getuid();
	if (is_root) {
		/* lttng health client socket path permissions */
		ret = chown(health_unix_sock_path, 0,
				utils_get_group_id(tracing_group_name));
		if (ret < 0) {
			ERR("Unable to set group on %s", health_unix_sock_path);
			PERROR("chown");
			ret = -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");
			ret = -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;
	}

	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)) {
					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);

		reply.ret_code = 0;
		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;
			}
		}

		DBG2("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
	18	#define _GNU_SOURCE
	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>
	39	#include <config.h>
	40	#include <urcu/compiler.h>
	41	#include <ulimit.h>
6c71277b	42	#include <inttypes.h>
5c635c72 MD	43
	44	#include <common/defaults.h>
	45	#include <common/common.h>
	46	#include <common/consumer.h>
	47	#include <common/consumer-timer.h>
	48	#include <common/compat/poll.h>
	49	#include <common/sessiond-comm/sessiond-comm.h>
	50	#include <common/utils.h>
	51
	52	#include "lttng-consumerd.h"
	53	#include "health-consumerd.h"
	54
	55	/* Global health check unix path */
	56	static char health_unix_sock_path[PATH_MAX];
	57
	58	int health_quit_pipe[2];
	59
	60	/*
	61	* Check if the thread quit pipe was triggered.
	62	*
	63	* Return 1 if it was triggered else 0;
	64	*/
	65	static
	66	int check_health_quit_pipe(int fd, uint32_t events)
	67	{
	68	if (fd == health_quit_pipe[0] && (events & LPOLLIN)) {
	69	return 1;
	70	}
	71
	72	return 0;
	73	}
	74
	75	/*
	76	* Send data on a unix socket using the liblttsessiondcomm API.
	77	*
	78	* Return lttcomm error code.
	79	*/
	80	static int send_unix_sock(int sock, void *buf, size_t len)
	81	{
	82	/* Check valid length */
	83	if (len == 0) {
	84	return -1;
	85	}
	86
	87	return lttcomm_send_unix_sock(sock, buf, len);
	88	}
	89
	90	static
	91	int setup_health_path(void)
	92	{
	93	int is_root, ret = 0;
	94	enum lttng_consumer_type type;
	95	const char *home_path;
	96
	97	type = lttng_consumer_get_type();
	98	is_root = !getuid();
	99
	100	if (is_root) {
	101	if (strlen(health_unix_sock_path) != 0) {
	102	goto end;
	103	}
	104	switch (type) {
	105	case LTTNG_CONSUMER_KERNEL:
	106	snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
107	DEFAULT_GLOBAL_KCONSUMER_HEALTH_UNIX_SOCK);
108	break;
109	case LTTNG_CONSUMER64_UST:
110	snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
111	DEFAULT_GLOBAL_USTCONSUMER64_HEALTH_UNIX_SOCK);
112	break;
113	case LTTNG_CONSUMER32_UST:
114	snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
115	DEFAULT_GLOBAL_USTCONSUMER32_HEALTH_UNIX_SOCK);
116	break;
117	default:
118	ret = -EINVAL;
119	goto end;
120	}
121	} else {
122	static char *rundir;
123
124	home_path = utils_get_home_dir();
125	if (home_path == NULL) {
126	/* TODO: Add --socket PATH option */
127	ERR("Can't get HOME directory for sockets creation.");
128	ret = -EPERM;
129	goto end;
130	}
131
132	/*
133	* Create rundir from home path. This will create something like
134	* $HOME/.lttng
135	*/
136	ret = asprintf(&rundir, DEFAULT_LTTNG_HOME_RUNDIR, home_path);
137	if (ret < 0) {
138	ret = -ENOMEM;
139	goto end;
140	}
141
142	/* Set health check Unix path */
143	if (strlen(health_unix_sock_path) != 0) {
144	goto end;
145	}
146	switch (type) {
147	case LTTNG_CONSUMER_KERNEL:
148	snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
149	DEFAULT_HOME_KCONSUMER_HEALTH_UNIX_SOCK, rundir);
150	break;
151	case LTTNG_CONSUMER64_UST:
152	snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
153	DEFAULT_HOME_USTCONSUMER64_HEALTH_UNIX_SOCK, rundir);
154	break;
155	case LTTNG_CONSUMER32_UST:
156	snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
157	DEFAULT_HOME_USTCONSUMER32_HEALTH_UNIX_SOCK, rundir);
158	break;
159	default:
160	ret = -EINVAL;
161	goto end;
162	}
163	}
164
165	end:
166	return ret;
167	}
168
169	/*
170	* Thread managing health check socket.
171	*/
172	void thread_manage_health(void data)
173	{
174	int sock = -1, new_sock = -1, ret, i, pollfd, err = -1;
175	uint32_t revents, nb_fd;
176	struct lttng_poll_event events;
177	struct health_comm_msg msg;
178	struct health_comm_reply reply;
6c71277b	179	int is_root;
5c635c72 MD	180
	181	DBG("[thread] Manage health check started");
	182
	183	setup_health_path();
	184
	185	rcu_register_thread();
	186
	187	/* We might hit an error path before this is created. */
	188	lttng_poll_init(&events);
	189
	190	/* Create unix socket */
	191	sock = lttcomm_create_unix_sock(health_unix_sock_path);
	192	if (sock < 0) {
	193	ERR("Unable to create health check Unix socket");
	194	ret = -1;
	195	goto error;
	196	}
	197
6c71277b MD	198	is_root = !getuid();
	199	if (is_root) {
	200	/* lttng health client socket path permissions */
	201	ret = chown(health_unix_sock_path, 0,
	202	utils_get_group_id(tracing_group_name));
	203	if (ret < 0) {
	204	ERR("Unable to set group on %s", health_unix_sock_path);
	205	PERROR("chown");
	206	ret = -1;
	207	goto error;
	208	}
	209
	210	ret = chmod(health_unix_sock_path,
	211	S_IRUSR \| S_IWUSR \| S_IRGRP \| S_IWGRP);
	212	if (ret < 0) {
	213	ERR("Unable to set permissions on %s", health_unix_sock_path);
	214	PERROR("chmod");
	215	ret = -1;
	216	goto error;
	217	}
	218	}
	219
5c635c72 MD	220	/*
	221	* Set the CLOEXEC flag. Return code is useless because either way, the
	222	* show must go on.
	223	*/
	224	(void) utils_set_fd_cloexec(sock);
	225
	226	ret = lttcomm_listen_unix_sock(sock);
	227	if (ret < 0) {
	228	goto error;
	229	}
	230
	231	/* Size is set to 1 for the consumer_channel pipe */
	232	ret = lttng_poll_create(&events, 2, LTTNG_CLOEXEC);
	233	if (ret < 0) {
	234	ERR("Poll set creation failed");
	235	goto error;
	236	}
	237
	238	ret = lttng_poll_add(&events, health_quit_pipe[0], LPOLLIN);
	239	if (ret < 0) {
	240	goto error;
	241	}
	242
	243	/* Add the application registration socket */
	244	ret = lttng_poll_add(&events, sock, LPOLLIN \| LPOLLPRI);
	245	if (ret < 0) {
	246	goto error;
	247	}
	248
	249	while (1) {
	250	DBG("Health check ready");
	251
	252	/* Inifinite blocking call, waiting for transmission */
	253	restart:
	254	ret = lttng_poll_wait(&events, -1);
	255	if (ret < 0) {
	256	/*
	257	* Restart interrupted system call.
	258	*/
	259	if (errno == EINTR) {
	260	goto restart;
	261	}
	262	goto error;
	263	}
	264
	265	nb_fd = ret;
	266
	267	for (i = 0; i < nb_fd; i++) {
	268	/* Fetch once the poll data */
	269	revents = LTTNG_POLL_GETEV(&events, i);
	270	pollfd = LTTNG_POLL_GETFD(&events, i);
	271
	272	/* Thread quit pipe has been closed. Killing thread. */
	273	ret = check_health_quit_pipe(pollfd, revents);
	274	if (ret) {
	275	err = 0;
	276	goto exit;
	277	}
	278
	279	/* Event on the registration socket */
	280	if (pollfd == sock) {
	281	if (revents & (LPOLLERR \| LPOLLHUP \| LPOLLRDHUP)) {
	282	ERR("Health socket poll error");
	283	goto error;
284	}
285	}
286	}
287
288	new_sock = lttcomm_accept_unix_sock(sock);
289	if (new_sock < 0) {
290	goto error;
291	}
292
293	/*
294	* Set the CLOEXEC flag. Return code is useless because either way, the
295	* show must go on.
296	*/
297	(void) utils_set_fd_cloexec(new_sock);
298
299	DBG("Receiving data from client for health...");
300	ret = lttcomm_recv_unix_sock(new_sock, (void *)&msg, sizeof(msg));
301	if (ret <= 0) {
302	DBG("Nothing recv() from client... continuing");
303	ret = close(new_sock);
304	if (ret) {
305	PERROR("close");
306	}
307	new_sock = -1;
308	continue;
309	}
310
311	rcu_thread_online();
312
313	assert(msg.cmd == HEALTH_CMD_CHECK);
314
6c71277b MD	315	reply.ret_code = 0;
	316	for (i = 0; i < NR_HEALTH_CONSUMERD_TYPES; i++) {
	317	/*
	318	* health_check_state return 0 if thread is in
	319	* error.
	320	*/
	321	if (!health_check_state(health_consumerd, i)) {
	322	reply.ret_code \|= 1ULL << i;
	323	}
5c635c72 MD	324	}
5c635c72 MD	325
6c71277b	326	DBG2("Health check return value %" PRIx64, reply.ret_code);
5c635c72 MD	327
	328	ret = send_unix_sock(new_sock, (void *) &reply, sizeof(reply));
	329	if (ret < 0) {
	330	ERR("Failed to send health data back to client");
	331	}
	332
	333	/* End of transmission */
	334	ret = close(new_sock);
	335	if (ret) {
	336	PERROR("close");
	337	}
	338	new_sock = -1;
	339	}
	340
	341	exit:
	342	error:
	343	if (err) {
	344	ERR("Health error occurred in %s", __func__);
	345	}
	346	DBG("Health check thread dying");
	347	unlink(health_unix_sock_path);
	348	if (sock >= 0) {
	349	ret = close(sock);
	350	if (ret) {
	351	PERROR("close");
	352	}
	353	}
	354
	355	lttng_poll_clean(&events);
	356
	357	rcu_unregister_thread();
	358	return NULL;
	359	}