X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-consumerd%2Fhealth-consumerd.cpp;fp=src%2Fbin%2Flttng-consumerd%2Fhealth-consumerd.cpp;h=90b4b1e12439eb9dcc34a265c20c37a3608668ce;hp=0000000000000000000000000000000000000000;hb=657d1bf105996bf8f6e13af697fb1112afa61b28;hpb=aa4e4813f3410c866cf8dbc42f6eaa038d704a22

diff --git a/src/bin/lttng-consumerd/health-consumerd.cpp b/src/bin/lttng-consumerd/health-consumerd.cpp
new file mode 100644
index 000000000..90b4b1e12
--- /dev/null
+++ b/src/bin/lttng-consumerd/health-consumerd.cpp
@@ -0,0 +1,346 @@
+/*
+ * Copyright (C) 2013 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ *
+ */
+
+#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 <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();
+
+		LTTNG_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;
+}