X-Git-Url: http://git.efficios.com/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Flttng-sessiond.h;h=9d0b9abd5dd40e2fe8b2b35cadaf4317e5e36952;hp=2ba2550c7a1bda4cdb6fa3d1ff2f1f9313ad35ae;hb=2463b7879c00298daa79744cdaae82ac061a4ed8;hpb=ca4537d385628d3568a918409d909d3042ca7a38 diff --git a/src/bin/lttng-sessiond/lttng-sessiond.h b/src/bin/lttng-sessiond/lttng-sessiond.h index 2ba2550c7..9d0b9abd5 100644 --- a/src/bin/lttng-sessiond/lttng-sessiond.h +++ b/src/bin/lttng-sessiond/lttng-sessiond.h @@ -1,66 +1,172 @@ /* - * Copyright (C) 2011 - David Goulet + * Copyright (C) 2011 David Goulet + * Copyright (C) 2013 Raphaël Beamonte * - * 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. + * SPDX-License-Identifier: GPL-2.0-only * - * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #ifndef _LTT_SESSIOND_H #define _LTT_SESSIOND_H -#define _LGPL_SOURCE #include -#include +#include #include +#include +#include +#include +#include #include "session.h" #include "ust-app.h" +#include "notification-thread.h" +#include "sessiond-config.h" + +/* + * 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, +}; -const char *module_proc_lttng = "/proc/lttng"; +/* 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 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; +extern pthread_mutex_t notification_trigger_tokens_ht_lock; + /* * 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 ucred creds; struct ltt_session *session; - struct lttcomm_lttng_msg *llm; - struct lttcomm_session_msg *lsm; + /* Input message */ + struct lttcomm_session_msg lsm; + /* Reply content, starts with an lttcomm_lttng_msg header. */ + struct lttng_payload reply_payload; + lttng_sock_cred creds; }; 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 */