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

   1 /*
   2  * Copyright (C) 2013 - David Goulet <dgoulet@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 LTTNG_BUFFER_REGISTRY_H
  19 #define LTTNG_BUFFER_REGISTRY_H
  20
  21 #include <stdint.h>
  22 #include <urcu/list.h>
  23
  24 #include <lttng/lttng.h>
  25 #include <common/hashtable/hashtable.h>
  26
  27 #include "consumer.h"
  28 #include "ust-ctl.h"
  29 #include "ust-registry.h"
  30
  31 struct buffer_reg_stream {
  32         struct cds_list_head lnode;
  33         union {
  34                 /* Original object data that MUST be copied over. */
  35                 struct lttng_ust_object_data *ust;
  36         } obj;
  37 };
  38
  39 struct buffer_reg_channel {
  40         /* This key is the same as a tracing channel key. */
  41         uint32_t key;
  42         /* Key of the channel on the consumer side. */
  43         uint64_t consumer_key;
  44         /* Stream registry object of this channel registry. */
  45         struct cds_list_head streams;
  46         /* Total number of stream in the list. */
  47         uint64_t stream_count;
  48         /* Used to ensure mutual exclusion to the stream's list. */
  49         pthread_mutex_t stream_list_lock;
  50         /* Node for hash table usage. */
  51         struct lttng_ht_node_u64 node;
  52         union {
  53                 /* Original object data that MUST be copied over. */
  54                 struct lttng_ust_object_data *ust;
  55         } obj;
  56 };
  57
  58 struct buffer_reg_session {
  59         /* Registry per domain. */
  60         union {
  61                 struct ust_registry_session *ust;
  62         } reg;
  63
  64         /* Contains buffer registry channel indexed by tracing channel key. */
  65         struct lttng_ht *channels;
  66 };
  67
  68 /*
  69  * Registry object for per UID buffers.
  70  */
  71 struct buffer_reg_uid {
  72         /*
  73          * Keys to match this object in a hash table. The following three variables
  74          * identify a unique per UID buffer registry.
  75          */
  76         uint64_t session_id;    /* Unique tracing session id. */
  77         int bits_per_long;      /* ABI */
  78         uid_t uid;                      /* Owner. */
  79
  80         enum lttng_domain_type domain;
  81         struct buffer_reg_session *registry;
  82
  83         /* Indexed by session id. */
  84         struct lttng_ht_node_u64 node;
  85         /* Node of a linked list used to teardown object at a destroy session. */
  86         struct cds_list_head lnode;
  87 };
  88
  89 /*
  90  * Registry object for per PID buffers.
  91  */
  92 struct buffer_reg_pid {
  93         uint64_t session_id;
  94
  95         struct buffer_reg_session *registry;
  96
  97         /* Indexed by session id. */
  98         struct lttng_ht_node_u64 node;
  99 };
 100
 101 /* Buffer registry per UID. */
 102 void buffer_reg_init_uid_registry(void);
 103 int buffer_reg_uid_create(uint64_t session_id, uint32_t bits_per_long, uid_t uid,
 104                 enum lttng_domain_type domain, struct buffer_reg_uid **regp);
 105 void buffer_reg_uid_add(struct buffer_reg_uid *reg);
 106 struct buffer_reg_uid *buffer_reg_uid_find(uint64_t session_id,
 107                 uint32_t bits_per_long, uid_t uid);
 108 void buffer_reg_uid_remove(struct buffer_reg_uid *regp);
 109 void buffer_reg_uid_destroy(struct buffer_reg_uid *regp,
 110                 struct consumer_output *consumer);
 111
 112 /* Buffer registry per PID. */
 113 void buffer_reg_init_pid_registry(void);
 114 int buffer_reg_pid_create(uint64_t session_id, struct buffer_reg_pid **regp);
 115 void buffer_reg_pid_add(struct buffer_reg_pid *reg);
 116 struct buffer_reg_pid *buffer_reg_pid_find(uint64_t session_id);
 117 void buffer_reg_pid_remove(struct buffer_reg_pid *regp);
 118 void buffer_reg_pid_destroy(struct buffer_reg_pid *regp);
 119
 120 /* Channel */
 121 int buffer_reg_channel_create(uint64_t key, struct buffer_reg_channel **regp);
 122 void buffer_reg_channel_add(struct buffer_reg_session *session,
 123                 struct buffer_reg_channel *channel);
 124 struct buffer_reg_channel *buffer_reg_channel_find(uint64_t key,
 125                 struct buffer_reg_uid *reg);
 126 void buffer_reg_channel_remove(struct buffer_reg_session *session,
 127                 struct buffer_reg_channel *regp);
 128 void buffer_reg_channel_destroy(struct buffer_reg_channel *regp,
 129                 enum lttng_domain_type domain);
 130
 131 /* Stream */
 132 int buffer_reg_stream_create(struct buffer_reg_stream **regp);
 133 void buffer_reg_stream_add(struct buffer_reg_stream *stream,
 134                 struct buffer_reg_channel *channel);
 135 void buffer_reg_stream_destroy(struct buffer_reg_stream *regp,
 136                 enum lttng_domain_type domain);
 137
 138 /* Global registry. */
 139 void buffer_reg_destroy_registries(void);
 140
 141 #endif /* LTTNG_BUFFER_REGISTRY_H */