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         /* Size of subbuffers in this channel. */
  53         size_t subbuf_size;
  54         union {
  55                 /* Original object data that MUST be copied over. */
  56                 struct lttng_ust_object_data *ust;
  57         } obj;
  58 };
  59
  60 struct buffer_reg_session {
  61         /* Registry per domain. */
  62         union {
  63                 struct ust_registry_session *ust;
  64         } reg;
  65
  66         /* Contains buffer registry channel indexed by tracing channel key. */
  67         struct lttng_ht *channels;
  68 };
  69
  70 /*
  71  * Registry object for per UID buffers.
  72  */
  73 struct buffer_reg_uid {
  74         /*
  75          * Keys to match this object in a hash table. The following three variables
  76          * identify a unique per UID buffer registry.
  77          */
  78         uint64_t session_id;    /* Unique tracing session id. */
  79         int bits_per_long;      /* ABI */
  80         uid_t uid;                      /* Owner. */
  81
  82         enum lttng_domain_type domain;
  83         struct buffer_reg_session *registry;
  84
  85         /* Indexed by session id. */
  86         struct lttng_ht_node_u64 node;
  87         /* Node of a linked list used to teardown object at a destroy session. */
  88         struct cds_list_head lnode;
  89 };
  90
  91 /*
  92  * Registry object for per PID buffers.
  93  */
  94 struct buffer_reg_pid {
  95         uint64_t session_id;
  96
  97         struct buffer_reg_session *registry;
  98
  99         /* Indexed by session id. */
 100         struct lttng_ht_node_u64 node;
 101 };
 102
 103 /* Buffer registry per UID. */
 104 void buffer_reg_init_uid_registry(void);
 105 int buffer_reg_uid_create(uint64_t session_id, uint32_t bits_per_long, uid_t uid,
 106                 enum lttng_domain_type domain, struct buffer_reg_uid **regp);
 107 void buffer_reg_uid_add(struct buffer_reg_uid *reg);
 108 struct buffer_reg_uid *buffer_reg_uid_find(uint64_t session_id,
 109                 uint32_t bits_per_long, uid_t uid);
 110 void buffer_reg_uid_remove(struct buffer_reg_uid *regp);
 111 void buffer_reg_uid_destroy(struct buffer_reg_uid *regp,
 112                 struct consumer_output *consumer);
 113
 114 /* Buffer registry per PID. */
 115 void buffer_reg_init_pid_registry(void);
 116 int buffer_reg_pid_create(uint64_t session_id, struct buffer_reg_pid **regp);
 117 void buffer_reg_pid_add(struct buffer_reg_pid *reg);
 118 struct buffer_reg_pid *buffer_reg_pid_find(uint64_t session_id);
 119 void buffer_reg_pid_remove(struct buffer_reg_pid *regp);
 120 void buffer_reg_pid_destroy(struct buffer_reg_pid *regp);
 121
 122 /* Channel */
 123 int buffer_reg_channel_create(uint64_t key, struct buffer_reg_channel **regp);
 124 void buffer_reg_channel_add(struct buffer_reg_session *session,
 125                 struct buffer_reg_channel *channel);
 126 struct buffer_reg_channel *buffer_reg_channel_find(uint64_t key,
 127                 struct buffer_reg_uid *reg);
 128 void buffer_reg_channel_remove(struct buffer_reg_session *session,
 129                 struct buffer_reg_channel *regp);
 130 void buffer_reg_channel_destroy(struct buffer_reg_channel *regp,
 131                 enum lttng_domain_type domain);
 132
 133 /* Stream */
 134 int buffer_reg_stream_create(struct buffer_reg_stream **regp);
 135 void buffer_reg_stream_add(struct buffer_reg_stream *stream,
 136                 struct buffer_reg_channel *channel);
 137 void buffer_reg_stream_destroy(struct buffer_reg_stream *regp,
 138                 enum lttng_domain_type domain);
 139
 140 /* Global registry. */
 141 void buffer_reg_destroy_registries(void);
 142
 143 #endif /* LTTNG_BUFFER_REGISTRY_H */