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 "version.h"
  32
  33 extern const char default_home_dir[],
  34         default_tracing_group[],
  35         default_ust_sock_dir[],
  36         default_global_apps_pipe[];
  37
  38 /* Set in main.c at boot time of the daemon */
  39 extern int kernel_tracer_fd;
  40
  41 /*
  42  * This contains extra data needed for processing a command received by the
  43  * session daemon from the lttng client.
  44  */
  45 struct command_ctx {
  46         int ust_sock;
  47         unsigned int lttng_msg_size;
  48         struct ltt_session *session;
  49         struct lttcomm_lttng_msg *llm;
  50         struct lttcomm_session_msg *lsm;
  51         lttng_sock_cred creds;
  52 };
  53
  54 struct ust_command {
  55         int sock;
  56         struct ust_register_msg reg_msg;
  57         struct cds_wfcq_node node;
  58 };
  59
  60 /*
  61  * Queue used to enqueue UST registration request (ust_commant) and protected
  62  * by a futex with a scheme N wakers / 1 waiters. See futex.c/.h
  63  */
  64 struct ust_cmd_queue {
  65         int32_t futex;
  66         struct cds_wfcq_head head;
  67         struct cds_wfcq_tail tail;
  68 };
  69
  70 /*
  71  * This is the wait queue containing wait nodes during the application
  72  * registration process.
  73  */
  74 struct ust_reg_wait_queue {
  75         unsigned long count;
  76         struct cds_list_head head;
  77 };
  78
  79 /*
  80  * Use by the dispatch registration to queue UST command socket to wait for the
  81  * notify socket.
  82  */
  83 struct ust_reg_wait_node {
  84         struct ust_app *app;
  85         struct cds_list_head head;
  86 };
  87
  88 /*
  89  * This pipe is used to inform the thread managing application notify
  90  * communication that a command is queued and ready to be processed.
  91  */
  92 extern int apps_cmd_notify_pipe[2];
  93
  94 /*
  95  * Used to notify that a hash table needs to be destroyed by dedicated
  96  * thread. Required by design because we don't want to move destroy
  97  * paths outside of large RCU read-side lock paths, and destroy cannot
  98  * be called by call_rcu thread, because it may hang (waiting for
  99  * call_rcu completion).
 100  */
 101 extern int ht_cleanup_pipe[2];
 102
 103 /*
 104  * Populated when the daemon starts with the current page size of the system.
 105  */
 106 extern long page_size;
 107
 108 /*
 109  * Global set once in main(). Agent TCP port for registration.
 110  */
 111 extern unsigned int agent_tcp_port;
 112
 113 /*
 114  * Section name to look for in the daemon configuration file.
 115  */
 116 extern const char * const config_section_name;
 117
 118 /* Is this daemon root or not. */
 119 extern int is_root;
 120
 121 int sessiond_set_thread_pollset(struct lttng_poll_event *events, size_t size);
 122 int sessiond_check_thread_quit_pipe(int fd, uint32_t events);
 123
 124 void *thread_ht_cleanup(void *data);
 125
 126 void sessiond_notify_ready(void);
 127
 128 #endif /* _LTT_SESSIOND_H */