src/bin/lttng-sessiond/trace-ust.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_TRACE_UST_H
  19 #define _LTT_TRACE_UST_H
  20
  21 #include <config.h>
  22 #include <limits.h>
  23 #include <urcu/list.h>
  24
  25 #include <lttng/lttng.h>
  26 #include <common/hashtable/hashtable.h>
  27 #include <common/defaults.h>
  28
  29 #include "consumer.h"
  30 #include "agent.h"
  31 #include "ust-ctl.h"
  32
  33 struct ltt_ust_ht_key {
  34         const char *name;
  35         const struct lttng_filter_bytecode *filter;
  36         enum lttng_ust_loglevel_type loglevel;
  37         const struct lttng_event_exclusion *exclusion;
  38 };
  39
  40 /* Context hash table nodes */
  41 struct ltt_ust_context {
  42         struct lttng_ust_context ctx;
  43         struct lttng_ht_node_ulong node;
  44         struct cds_list_head list;
  45 };
  46
  47 /* UST event */
  48 struct ltt_ust_event {
  49         unsigned int enabled;
  50         struct lttng_ust_event attr;
  51         struct lttng_ht_node_str node;
  52         char *filter_expression;
  53         struct lttng_ust_filter_bytecode *filter;
  54         struct lttng_event_exclusion *exclusion;
  55 };
  56
  57 /* UST channel */
  58 struct ltt_ust_channel {
  59         uint64_t id;    /* unique id per session. */
  60         unsigned int enabled;
  61         char name[LTTNG_UST_SYM_NAME_LEN];
  62         struct lttng_ust_channel_attr attr;
  63         struct lttng_ht *ctx;
  64         struct cds_list_head ctx_list;
  65         struct lttng_ht *events;
  66         struct lttng_ht_node_str node;
  67         uint64_t tracefile_size;
  68         uint64_t tracefile_count;
  69 };
  70
  71 /* UST domain global (LTTNG_DOMAIN_UST) */
  72 struct ltt_ust_domain_global {
  73         struct lttng_ht *channels;
  74         struct cds_list_head registry_buffer_uid_list;
  75 };
  76
  77 /* UST session */
  78 struct ltt_ust_session {
  79         uint64_t id;    /* Unique identifier of session */
  80         struct ltt_ust_domain_global domain_global;
  81         /* Hash table of agent indexed by agent domain. */
  82         struct lttng_ht *agents;
  83         /* UID/GID of the user owning the session */
  84         uid_t uid;
  85         gid_t gid;
  86         /* Is the session active meaning has is been started or stopped. */
  87         unsigned int active:1;
  88         struct consumer_output *consumer;
  89         /* Sequence number for filters so the tracer knows the ordering. */
  90         uint64_t filter_seq_num;
  91         /* This indicates which type of buffer this session is set for. */
  92         enum lttng_buffer_type buffer_type;
  93         /* If set to 1, the buffer_type can not be changed anymore. */
  94         int buffer_type_changed;
  95         /* For per UID buffer, every buffer reg object is kept of this session */
  96         struct cds_list_head buffer_reg_uid_list;
  97         /* Next channel ID available for a newly registered channel. */
  98         uint64_t next_channel_id;
  99         /* Once this value reaches UINT32_MAX, no more id can be allocated. */
 100         uint64_t used_channel_id;
 101         /* Tell or not if the session has to output the traces. */
 102         unsigned int output_traces;
 103         unsigned int snapshot_mode;
 104         unsigned int has_non_default_channel;
 105         unsigned int live_timer_interval;       /* usec */
 106
 107         /* Metadata channel attributes. */
 108         struct lttng_ust_channel_attr metadata_attr;
 109 };
 110
 111 /*
 112  * Validate that the id has reached the maximum allowed or not.
 113  *
 114  * Return 0 if NOT else 1.
 115  */
 116 static inline int trace_ust_is_max_id(uint64_t id)
 117 {
 118         return (id == UINT64_MAX) ? 1 : 0;
 119 }
 120
 121 /*
 122  * Return next available channel id and increment the used counter. The
 123  * trace_ust_is_max_id function MUST be called before in order to validate if
 124  * the maximum number of IDs have been reached. If not, it is safe to call this
 125  * function.
 126  *
 127  * Return a unique channel ID. If max is reached, the used_channel_id counter
 128  * is returned.
 129  */
 130 static inline uint64_t trace_ust_get_next_chan_id(struct ltt_ust_session *s)
 131 {
 132         if (trace_ust_is_max_id(s->used_channel_id)) {
 133                 return s->used_channel_id;
 134         }
 135
 136         s->used_channel_id++;
 137         return s->next_channel_id++;
 138 }
 139
 140 #ifdef HAVE_LIBLTTNG_UST_CTL
 141
 142 int trace_ust_ht_match_event(struct cds_lfht_node *node, const void *_key);
 143 int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
 144                 const void *_key);
 145
 146 /*
 147  * Lookup functions. NULL is returned if not found.
 148  */
 149 struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
 150                 char *name, struct lttng_filter_bytecode *filter, int loglevel,
 151                 struct lttng_event_exclusion *exclusion);
 152 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 153                 char *name);
 154 struct agent *trace_ust_find_agent(struct ltt_ust_session *session,
 155                 enum lttng_domain_type domain_type);
 156
 157 /*
 158  * Create functions malloc() the data structure.
 159  */
 160 struct ltt_ust_session *trace_ust_create_session(uint64_t session_id);
 161 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *attr);
 162 struct ltt_ust_event *trace_ust_create_event(struct lttng_event *ev,
 163                 char *filter_expression,
 164                 struct lttng_filter_bytecode *filter,
 165                 struct lttng_event_exclusion *exclusion);
 166 struct ltt_ust_context *trace_ust_create_context(
 167                 struct lttng_event_context *ctx);
 168 int trace_ust_match_context(struct ltt_ust_context *uctx,
 169                 struct lttng_event_context *ctx);
 170 void trace_ust_delete_channel(struct lttng_ht *ht,
 171                 struct ltt_ust_channel *channel);
 172
 173 /*
 174  * Destroy functions free() the data structure and remove from linked list if
 175  * it's applies.
 176  */
 177 void trace_ust_destroy_session(struct ltt_ust_session *session);
 178 void trace_ust_destroy_channel(struct ltt_ust_channel *channel);
 179 void trace_ust_destroy_event(struct ltt_ust_event *event);
 180
 181 #else /* HAVE_LIBLTTNG_UST_CTL */
 182
 183 static inline int trace_ust_ht_match_event(struct cds_lfht_node *node,
 184                 const void *_key)
 185 {
 186         return 0;
 187 }
 188 static inline int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
 189                 const void *_key)
 190 {
 191         return 0;
 192 }
 193 static inline
 194 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 195                 char *name)
 196 {
 197         return NULL;
 198 }
 199
 200 static inline
 201 struct ltt_ust_session *trace_ust_create_session(unsigned int session_id)
 202 {
 203         return NULL;
 204 }
 205 static inline
 206 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *attr)
 207 {
 208         return NULL;
 209 }
 210 static inline
 211 struct ltt_ust_event *trace_ust_create_event(struct lttng_event *ev,
 212                 const char *filter_expression,
 213                 struct lttng_filter_bytecode *filter,
 214                 struct lttng_event_exclusion *exclusion)
 215 {
 216         return NULL;
 217 }
 218 static inline
 219 void trace_ust_destroy_session(struct ltt_ust_session *session)
 220 {
 221 }
 222
 223 static inline
 224 void trace_ust_destroy_channel(struct ltt_ust_channel *channel)
 225 {
 226 }
 227
 228 static inline
 229 void trace_ust_destroy_event(struct ltt_ust_event *event)
 230 {
 231 }
 232 static inline
 233 struct ltt_ust_context *trace_ust_create_context(
 234                 struct lttng_event_context *ctx)
 235 {
 236         return NULL;
 237 }
 238 static inline
 239 int trace_ust_match_context(struct ltt_ust_context *uctx,
 240                 struct lttng_event_context *ctx)
 241 {
 242         return 0;
 243 }
 244 static inline struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
 245                 char *name, struct lttng_filter_bytecode *filter, int loglevel,
 246                 struct lttng_event_exclusion *exclusion)
 247 {
 248         return NULL;
 249 }
 250 static inline
 251 void trace_ust_delete_channel(struct lttng_ht *ht,
 252                 struct ltt_ust_channel *channel)
 253 {
 254         return;
 255 }
 256 static inline
 257 struct agent *trace_ust_find_agent(struct ltt_ust_session *session,
 258                 enum lttng_domain_type domain_type)
 259 {
 260         return NULL;
 261 }
 262
 263 #endif /* HAVE_LIBLTTNG_UST_CTL */
 264
 265 #endif /* _LTT_TRACE_UST_H */