src/bin/lttng-sessiond/rotate.cpp

   1 /*
   2  * Copyright (C) 2017 Julien Desfossez <jdesfossez@efficios.com>
   3  * Copyright (C) 2018 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   4  *
   5  * SPDX-License-Identifier: GPL-2.0-only
   6  *
   7  */
   8
   9 #define _LGPL_SOURCE
  10 #include <lttng/trigger/trigger.h>
  11 #include <common/error.hpp>
  12 #include <common/config/session-config.hpp>
  13 #include <common/defaults.hpp>
  14 #include <common/utils.hpp>
  15 #include <common/futex.hpp>
  16 #include <common/align.hpp>
  17 #include <common/time.hpp>
  18 #include <common/hashtable/utils.hpp>
  19 #include <common/kernel-ctl/kernel-ctl.hpp>
  20 #include <common/credentials.hpp>
  21 #include <sys/stat.h>
  22 #include <time.h>
  23 #include <signal.h>
  24 #include <inttypes.h>
  25
  26 #include <lttng/notification/channel-internal.hpp>
  27 #include <lttng/rotate-internal.hpp>
  28 #include <lttng/condition/condition-internal.hpp>
  29 #include <lttng/action/action-internal.hpp>
  30
  31 #include "session.hpp"
  32 #include "rotate.hpp"
  33 #include "rotation-thread.hpp"
  34 #include "lttng-sessiond.hpp"
  35 #include "health-sessiond.hpp"
  36 #include "cmd.hpp"
  37 #include "utils.hpp"
  38 #include "notification-thread-commands.hpp"
  39
  40 #include <urcu.h>
  41 #include <urcu/list.h>
  42 #include <urcu/rculfhash.h>
  43
  44 int subscribe_session_consumed_size_rotation(struct ltt_session *session, uint64_t size,
  45                 struct notification_thread_handle *notification_thread_handle)
  46 {
  47         int ret;
  48         enum lttng_condition_status condition_status;
  49         enum lttng_notification_channel_status nc_status;
  50         struct lttng_condition *rotate_condition = nullptr;
  51         struct lttng_action *notify_action = nullptr;
  52         const struct lttng_credentials session_creds = {
  53                 .uid = LTTNG_OPTIONAL_INIT_VALUE(session->uid),
  54                 .gid = LTTNG_OPTIONAL_INIT_VALUE(session->gid),
  55         };
  56
  57         rotate_condition = lttng_condition_session_consumed_size_create();
  58         if (!rotate_condition) {
  59                 ERR("Failed to create session consumed size condition object");
  60                 ret = -1;
  61                 goto end;
  62         }
  63
  64         condition_status = lttng_condition_session_consumed_size_set_threshold(
  65                         rotate_condition, size);
  66         if (condition_status != LTTNG_CONDITION_STATUS_OK) {
  67                 ERR("Could not set session consumed size condition threshold (size = %" PRIu64 ")",
  68                                 size);
  69                 ret = -1;
  70                 goto end;
  71         }
  72
  73         condition_status =
  74                         lttng_condition_session_consumed_size_set_session_name(
  75                                 rotate_condition, session->name);
  76         if (condition_status != LTTNG_CONDITION_STATUS_OK) {
  77                 ERR("Could not set session consumed size condition session name (name = %s)",
  78                                 session->name);
  79                 ret = -1;
  80                 goto end;
  81         }
  82
  83         notify_action = lttng_action_notify_create();
  84         if (!notify_action) {
  85                 ERR("Could not create notify action");
  86                 ret = -1;
  87                 goto end;
  88         }
  89
  90         LTTNG_ASSERT(!session->rotate_trigger);
  91         session->rotate_trigger = lttng_trigger_create(rotate_condition,
  92                         notify_action);
  93         if (!session->rotate_trigger) {
  94                 ERR("Could not create size-based rotation trigger");
  95                 ret = -1;
  96                 goto end;
  97         }
  98
  99         /* Ensure this trigger is not visible to external users. */
 100         lttng_trigger_set_hidden(session->rotate_trigger);
 101         lttng_trigger_set_credentials(
 102                         session->rotate_trigger, &session_creds);
 103
 104         nc_status = lttng_notification_channel_subscribe(
 105                         rotate_notification_channel, rotate_condition);
 106         if (nc_status != LTTNG_NOTIFICATION_CHANNEL_STATUS_OK) {
 107                 ERR("Could not subscribe to session consumed size notification");
 108                 ret = -1;
 109                 goto end;
 110         }
 111
 112         ret = notification_thread_command_register_trigger(
 113                         notification_thread_handle, session->rotate_trigger,
 114                         true);
 115         if (ret < 0 && ret != -LTTNG_ERR_TRIGGER_EXISTS) {
 116                 ERR("Register trigger, %s", lttng_strerror(ret));
 117                 ret = -1;
 118                 goto end;
 119         }
 120
 121         ret = 0;
 122
 123 end:
 124         lttng_condition_put(rotate_condition);
 125         lttng_action_put(notify_action);
 126         if (ret) {
 127                 lttng_trigger_put(session->rotate_trigger);
 128         }
 129         return ret;
 130 }
 131
 132 int unsubscribe_session_consumed_size_rotation(struct ltt_session *session,
 133                 struct notification_thread_handle *notification_thread_handle)
 134 {
 135         int ret = 0;
 136         enum lttng_notification_channel_status status;
 137
 138         LTTNG_ASSERT(session->rotate_trigger);
 139         status = lttng_notification_channel_unsubscribe(
 140                         rotate_notification_channel,
 141                         lttng_trigger_get_const_condition(session->rotate_trigger));
 142         if (status != LTTNG_NOTIFICATION_CHANNEL_STATUS_OK) {
 143                 ERR("Session unsubscribe error: %d", (int) status);
 144                 ret = -1;
 145                 goto end;
 146         }
 147
 148         ret = notification_thread_command_unregister_trigger(
 149                         notification_thread_handle, session->rotate_trigger);
 150         if (ret != LTTNG_OK) {
 151                 ERR("Session unregister trigger error: %d", ret);
 152                 goto end;
 153         }
 154
 155         lttng_trigger_put(session->rotate_trigger);
 156         session->rotate_trigger = nullptr;
 157
 158         ret = 0;
 159 end:
 160         return ret;
 161 }