src/bin/lttng-sessiond/lttng-sessiond.h

   1 /*
   2  * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
   3  * Copyright (C) 2013 - Raphaël Beamonte <raphael.beamonte@gmail.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License, version 2 only,
   7  * as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along
  15  * with this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  17  */
  18
  19 #ifndef _LTT_SESSIOND_H
  20 #define _LTT_SESSIOND_H
  21
  22 #include <urcu.h>
  23 #include <urcu/wfcqueue.h>
  24
  25 #include <common/sessiond-comm/sessiond-comm.h>
  26 #include <common/compat/poll.h>
  27 #include <common/compat/socket.h>
  28
  29 #include "session.h"
  30 #include "ust-app.h"
  31 #include "notification-thread.h"
  32 #include "sessiond-config.h"
  33
  34 extern const char default_home_dir[],
  35         default_tracing_group[],
  36         default_ust_sock_dir[],
  37         default_global_apps_pipe[];
  38
  39 /* Set in main.c at boot time of the daemon */
  40 extern int kernel_tracer_fd;
  41
  42 extern struct notification_thread_handle *notification_thread_handle;
  43
  44 /*
  45  * This contains extra data needed for processing a command received by the
  46  * session daemon from the lttng client.
  47  */
  48 struct command_ctx {
  49         int ust_sock;
  50         unsigned int lttng_msg_size;
  51         struct ltt_session *session;
  52         struct lttcomm_lttng_msg *llm;
  53         struct lttcomm_session_msg *lsm;
  54         lttng_sock_cred creds;
  55 };
  56
  57 struct ust_command {
  58         int sock;
  59         struct ust_register_msg reg_msg;
  60         struct cds_wfcq_node node;
  61 };
  62
  63 /*
  64  * Queue used to enqueue UST registration request (ust_command) and synchronized
  65  * by a futex with a scheme N wakers / 1 waiters. See futex.c/.h
  66  */
  67 struct ust_cmd_queue {
  68         int32_t futex;
  69         struct cds_wfcq_head head;
  70         struct cds_wfcq_tail tail;
  71 };
  72
  73 /*
  74  * This is the wait queue containing wait nodes during the application
  75  * registration process.
  76  */
  77 struct ust_reg_wait_queue {
  78         unsigned long count;
  79         struct cds_list_head head;
  80 };
  81
  82 /*
  83  * Use by the dispatch registration to queue UST command socket to wait for the
  84  * notify socket.
  85  */
  86 struct ust_reg_wait_node {
  87         struct ust_app *app;
  88         struct cds_list_head head;
  89 };
  90
  91 /*
  92  * This pipe is used to inform the thread managing application notify
  93  * communication that a command is queued and ready to be processed.
  94  */
  95 extern int apps_cmd_notify_pipe[2];
  96
  97 /*
  98  * Used to notify that a hash table needs to be destroyed by dedicated
  99  * thread. Required by design because we don't want to move destroy
 100  * paths outside of large RCU read-side lock paths, and destroy cannot
 101  * be called by call_rcu thread, because it may hang (waiting for
 102  * call_rcu completion).
 103  */
 104 extern int ht_cleanup_pipe[2];
 105
 106 /*
 107  * Populated when the daemon starts with the current page size of the system.
 108  */
 109 extern long page_size;
 110
 111 /* Application health monitoring */
 112 extern struct health_app *health_sessiond;
 113
 114 /*
 115  * Section name to look for in the daemon configuration file.
 116  */
 117 extern const char * const config_section_name;
 118
 119 /* Is this daemon root or not. */
 120 extern int is_root;
 121
 122 extern struct sessiond_config config;
 123
 124 int sessiond_check_thread_quit_pipe(int fd, uint32_t events);
 125 int sessiond_set_thread_pollset(struct lttng_poll_event *events, size_t size);
 126 void sessiond_notify_ready(void);
 127 void sessiond_signal_parents(void);
 128
 129 #endif /* _LTT_SESSIOND_H */