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 #define _LGPL_SOURCE
  23 #include <urcu.h>
  24 #include <urcu/wfcqueue.h>
  25
  26 #include <common/sessiond-comm/sessiond-comm.h>
  27 #include <common/compat/poll.h>
  28 #include <common/compat/socket.h>
  29
  30 #include "session.h"
  31 #include "ust-app.h"
  32 #include "version.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 /*
  43  * This contains extra data needed for processing a command received by the
  44  * session daemon from the lttng client.
  45  */
  46 struct command_ctx {
  47         int ust_sock;
  48         unsigned int lttng_msg_size;
  49         struct ltt_session *session;
  50         struct lttcomm_lttng_msg *llm;
  51         struct lttcomm_session_msg *lsm;
  52         lttng_sock_cred creds;
  53 };
  54
  55 struct ust_command {
  56         int sock;
  57         struct ust_register_msg reg_msg;
  58         struct cds_wfcq_node node;
  59 };
  60
  61 /*
  62  * Queue used to enqueue UST registration request (ust_commant) and protected
  63  * by a futex with a scheme N wakers / 1 waiters. See futex.c/.h
  64  */
  65 struct ust_cmd_queue {
  66         int32_t futex;
  67         struct cds_wfcq_head head;
  68         struct cds_wfcq_tail tail;
  69 };
  70
  71 /*
  72  * This is the wait queue containing wait nodes during the application
  73  * registration process.
  74  */
  75 struct ust_reg_wait_queue {
  76         unsigned long count;
  77         struct cds_list_head head;
  78 };
  79
  80 /*
  81  * Use by the dispatch registration to queue UST command socket to wait for the
  82  * notify socket.
  83  */
  84 struct ust_reg_wait_node {
  85         struct ust_app *app;
  86         struct cds_list_head head;
  87 };
  88
  89 /*
  90  * This pipe is used to inform the thread managing application notify
  91  * communication that a command is queued and ready to be processed.
  92  */
  93 extern int apps_cmd_notify_pipe[2];
  94
  95 /*
  96  * Used to notify that a hash table needs to be destroyed by dedicated
  97  * thread. Required by design because we don't want to move destroy
  98  * paths outside of large RCU read-side lock paths, and destroy cannot
  99  * be called by call_rcu thread, because it may hang (waiting for
 100  * call_rcu completion).
 101  */
 102 extern int ht_cleanup_pipe[2];
 103
 104 /*
 105  * Populated when the daemon starts with the current page size of the system.
 106  */
 107 extern long page_size;
 108
 109 /*
 110  * Global set once in main(). JUL TCP port for registration.
 111  */
 112 extern unsigned int jul_tcp_port;
 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 int sessiond_set_thread_pollset(struct lttng_poll_event *events, size_t size);
 123 int sessiond_check_thread_quit_pipe(int fd, uint32_t events);
 124
 125 void *thread_ht_cleanup(void *data);
 126
 127 void sessiond_notify_ready(void);
 128
 129 #endif /* _LTT_SESSIOND_H */