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

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