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

   1 /*
   2  * Copyright (C) 2017 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License, version 2 only, as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, write to the Free Software Foundation, Inc., 51
  15  * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  16  */
  17
  18 #ifndef NOTIFICATION_THREAD_H
  19 #define NOTIFICATION_THREAD_H
  20
  21 #include <urcu/wfcqueue.h>
  22 #include <lttng/trigger/trigger.h>
  23 #include <pthread.h>
  24
  25 enum notification_command_type {
  26         NOTIFICATION_COMMAND_TYPE_NEW_TRIGGER,
  27 };
  28
  29 struct notification_command {
  30         /* Futex on which to wait for command reply. */
  31         int32_t futex;
  32         enum lttng_error_code result;
  33         enum notification_command_type type;
  34 };
  35
  36 struct notification_new_trigger_command {
  37         struct notification_command parent;
  38         /* Set to NULL if ownership was transfered. */
  39         struct lttng_trigger *trigger;
  40 };
  41
  42 /* Data passed to the thread on initialization. */
  43 struct notification_thread_data {
  44         /*
  45          * Queue of struct notification command.
  46          * event_fd must be WRITE(2) to signal that a new command
  47          * has been enqueued.
  48          */
  49         struct notification_cmd_queue {
  50                 int event_fd;
  51                 struct cds_list_head list;
  52                 pthread_mutex_t lock;
  53         } cmd_queue;
  54 };
  55
  56 struct notification_command *notification_new_trigger_command_create(
  57                 struct lttng_trigger *trigger);
  58 struct notification_command *notification_new_trigger_command_destroy(
  59                 struct lttng_trigger *trigger);
  60
  61 void *thread_notification(void *data);
  62
  63 struct notification_thread_data *notification_init_data(void);
  64 void notification_destroy_data(struct notification_thread_data *data);
  65
  66 #endif /* NOTIFICATION_THREAD_H */