/*
* Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
+ * Copyright (C) 2013 - Raphaël Beamonte <raphael.beamonte@gmail.com>
*
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; only version 2
- * of the License.
+ * 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
+ * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * 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.
*/
#ifndef _LTT_SESSIOND_H
#define _LTT_SESSIOND_H
-#define _LGPL_SOURCE
#include <urcu.h>
-#include <urcu/wfqueue.h>
+#include <urcu/wfcqueue.h>
#include <common/sessiond-comm/sessiond-comm.h>
+#include <common/compat/poll.h>
#include <common/compat/socket.h>
+#include <common/compat/uuid.h>
#include "session.h"
#include "ust-app.h"
+#include "notification-thread.h"
+#include "sessiond-config.h"
-const char *module_proc_lttng = "/proc/lttng";
+/*
+ * Consumer daemon state which is changed when spawning it, killing it or in
+ * case of a fatal error.
+ */
+enum consumerd_state {
+ CONSUMER_STARTED = 1,
+ CONSUMER_STOPPED = 2,
+ CONSUMER_ERROR = 3,
+};
+
+/* Unique identifier of a session daemon instance. */
+extern lttng_uuid sessiond_uuid;
+
+/*
+ * This consumer daemon state is used to validate if a client command will be
+ * able to reach the consumer. If not, the client is informed. For instance,
+ * doing a "lttng start" when the consumer state is set to ERROR will return an
+ * error to the client.
+ *
+ * The following example shows a possible race condition of this scheme:
+ *
+ * consumer thread error happens
+ * client cmd arrives
+ * client cmd checks state -> still OK
+ * consumer thread exit, sets error
+ * client cmd try to talk to consumer
+ * ...
+ *
+ * However, since the consumer is a different daemon, we have no way of making
+ * sure the command will reach it safely even with this state flag. This is why
+ * we consider that up to the state validation during command processing, the
+ * command is safe. After that, we can not guarantee the correctness of the
+ * client request vis-a-vis the consumer.
+ */
+extern enum consumerd_state ust_consumerd_state;
+extern enum consumerd_state kernel_consumerd_state;
extern const char default_home_dir[],
default_tracing_group[],
default_ust_sock_dir[],
default_global_apps_pipe[];
+/* Set in main.c at boot time of the daemon */
+extern int kernel_tracer_fd;
+extern struct lttng_kernel_tracer_version kernel_tracer_version;
+extern struct lttng_kernel_tracer_abi_version kernel_tracer_abi_version;
+
+/* Notification thread handle. */
+extern struct notification_thread_handle *notification_thread_handle;
+
/*
* This contains extra data needed for processing a command received by the
* session daemon from the lttng client.
*/
struct command_ctx {
- int ust_sock;
unsigned int lttng_msg_size;
struct ltt_session *session;
struct lttcomm_lttng_msg *llm;
struct ust_command {
int sock;
struct ust_register_msg reg_msg;
- struct cds_wfq_node node;
+ struct cds_wfcq_node node;
};
/*
- * Queue used to enqueue UST registration request (ust_commant) and protected
+ * Queue used to enqueue UST registration request (ust_command) and synchronized
* by a futex with a scheme N wakers / 1 waiters. See futex.c/.h
*/
struct ust_cmd_queue {
int32_t futex;
- struct cds_wfq_queue queue;
+ struct cds_wfcq_head head;
+ struct cds_wfcq_tail tail;
+};
+
+/*
+ * This is the wait queue containing wait nodes during the application
+ * registration process.
+ */
+struct ust_reg_wait_queue {
+ unsigned long count;
+ struct cds_list_head head;
+};
+
+/*
+ * Use by the dispatch registration to queue UST command socket to wait for the
+ * notify socket.
+ */
+struct ust_reg_wait_node {
+ struct ust_app *app;
+ struct cds_list_head head;
};
+/*
+ * Used to notify that a hash table needs to be destroyed by dedicated
+ * thread. Required by design because we don't want to move destroy
+ * paths outside of large RCU read-side lock paths, and destroy cannot
+ * be called by call_rcu thread, because it may hang (waiting for
+ * call_rcu completion).
+ */
+extern int ht_cleanup_pipe[2];
+
+extern int kernel_poll_pipe[2];
+
+/*
+ * Populated when the daemon starts with the current page size of the system.
+ * Set in main() with the current page size.
+ */
+extern long page_size;
+
+/* Application health monitoring */
+extern struct health_app *health_sessiond;
+
+extern struct sessiond_config config;
+
+extern int ust_consumerd64_fd, ust_consumerd32_fd;
+
+/* Parent PID for --sig-parent option */
+extern pid_t ppid;
+/* Internal parent PID use with daemonize. */
+extern pid_t child_ppid;
+
+/* Consumer daemon specific control data. */
+extern struct consumer_data ustconsumer32_data;
+extern struct consumer_data ustconsumer64_data;
+extern struct consumer_data kconsumer_data;
+
+int sessiond_init_thread_quit_pipe(void);
+int sessiond_check_thread_quit_pipe(int fd, uint32_t events);
+int sessiond_wait_for_quit_pipe(int timeout_ms);
+int sessiond_notify_quit_pipe(void);
+void sessiond_close_quit_pipe(void);
+
+int sessiond_set_thread_pollset(struct lttng_poll_event *events, size_t size);
+void sessiond_signal_parents(void);
+
+void sessiond_set_client_thread_state(bool running);
+void sessiond_wait_client_thread_stopped(void);
+
+void *thread_manage_consumer(void *data);
+
#endif /* _LTT_SESSIOND_H */
projects / lttng-tools.git / blobdiff