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         /*
  89          * Two consumer_output object are needed where one is for the current
  90          * output object and the second one is the temporary object used to store
  91          * URI being set by the lttng_set_consumer_uri call. Once
  92          * lttng_enable_consumer is called, the two pointers are swapped.
  93          */
  94         struct consumer_output *consumer;
  95         struct consumer_output *tmp_consumer;
  96         /* Sequence number for filters so the tracer knows the ordering. */
  97         uint64_t filter_seq_num;
  98         /* This indicates which type of buffer this session is set for. */
  99         enum lttng_buffer_type buffer_type;
 100         /* If set to 1, the buffer_type can not be changed anymore. */
 101         int buffer_type_changed;
 102         /* For per UID buffer, every buffer reg object is kept of this session */
 103         struct cds_list_head buffer_reg_uid_list;
 104         /* Next channel ID available for a newly registered channel. */
 105         uint64_t next_channel_id;
 106         /* Once this value reaches UINT32_MAX, no more id can be allocated. */
 107         uint64_t used_channel_id;
 108         /* Tell or not if the session has to output the traces. */
 109         unsigned int output_traces;
 110         unsigned int snapshot_mode;
 111         unsigned int has_non_default_channel;
 112         unsigned int live_timer_interval;       /* usec */
 113
 114         /* Metadata channel attributes. */
 115         struct lttng_ust_channel_attr metadata_attr;
 116
 117         /*
 118          * Path where to keep the shared memory files.
 119          */
 120         char root_shm_path[PATH_MAX];
 121         char shm_path[PATH_MAX];
 122 };
 123
 124 /*
 125  * Validate that the id has reached the maximum allowed or not.
 126  *
 127  * Return 0 if NOT else 1.
 128  */
 129 static inline int trace_ust_is_max_id(uint64_t id)
 130 {
 131         return (id == UINT64_MAX) ? 1 : 0;
 132 }
 133
 134 /*
 135  * Return next available channel id and increment the used counter. The
 136  * trace_ust_is_max_id function MUST be called before in order to validate if
 137  * the maximum number of IDs have been reached. If not, it is safe to call this
 138  * function.
 139  *
 140  * Return a unique channel ID. If max is reached, the used_channel_id counter
 141  * is returned.
 142  */
 143 static inline uint64_t trace_ust_get_next_chan_id(struct ltt_ust_session *s)
 144 {
 145         if (trace_ust_is_max_id(s->used_channel_id)) {
 146                 return s->used_channel_id;
 147         }
 148
 149         s->used_channel_id++;
 150         return s->next_channel_id++;
 151 }
 152
 153 #ifdef HAVE_LIBLTTNG_UST_CTL
 154
 155 int trace_ust_ht_match_event(struct cds_lfht_node *node, const void *_key);
 156 int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
 157                 const void *_key);
 158
 159 /*
 160  * Lookup functions. NULL is returned if not found.
 161  */
 162 struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
 163                 char *name, struct lttng_filter_bytecode *filter, int loglevel,
 164                 struct lttng_event_exclusion *exclusion);
 165 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 166                 char *name);
 167 struct agent *trace_ust_find_agent(struct ltt_ust_session *session,
 168                 enum lttng_domain_type domain_type);
 169
 170 /*
 171  * Create functions malloc() the data structure.
 172  */
 173 struct ltt_ust_session *trace_ust_create_session(uint64_t session_id);
 174 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *attr);
 175 struct ltt_ust_event *trace_ust_create_event(struct lttng_event *ev,
 176                 char *filter_expression,
 177                 struct lttng_filter_bytecode *filter,
 178                 struct lttng_event_exclusion *exclusion);
 179 struct ltt_ust_context *trace_ust_create_context(
 180                 struct lttng_event_context *ctx);
 181 int trace_ust_match_context(struct ltt_ust_context *uctx,
 182                 struct lttng_event_context *ctx);
 183 void trace_ust_delete_channel(struct lttng_ht *ht,
 184                 struct ltt_ust_channel *channel);
 185
 186 /*
 187  * Destroy functions free() the data structure and remove from linked list if
 188  * it's applies.
 189  */
 190 void trace_ust_destroy_session(struct ltt_ust_session *session);
 191 void trace_ust_destroy_channel(struct ltt_ust_channel *channel);
 192 void trace_ust_destroy_event(struct ltt_ust_event *event);
 193
 194 #else /* HAVE_LIBLTTNG_UST_CTL */
 195
 196 static inline int trace_ust_ht_match_event(struct cds_lfht_node *node,
 197                 const void *_key)
 198 {
 199         return 0;
 200 }
 201 static inline int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
 202                 const void *_key)
 203 {
 204         return 0;
 205 }
 206 static inline
 207 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 208                 char *name)
 209 {
 210         return NULL;
 211 }
 212
 213 static inline
 214 struct ltt_ust_session *trace_ust_create_session(unsigned int session_id)
 215 {
 216         return NULL;
 217 }
 218 static inline
 219 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *attr)
 220 {
 221         return NULL;
 222 }
 223 static inline
 224 struct ltt_ust_event *trace_ust_create_event(struct lttng_event *ev,
 225                 const char *filter_expression,
 226                 struct lttng_filter_bytecode *filter,
 227                 struct lttng_event_exclusion *exclusion)
 228 {
 229         return NULL;
 230 }
 231 static inline
 232 void trace_ust_destroy_session(struct ltt_ust_session *session)
 233 {
 234 }
 235
 236 static inline
 237 void trace_ust_destroy_channel(struct ltt_ust_channel *channel)
 238 {
 239 }
 240
 241 static inline
 242 void trace_ust_destroy_event(struct ltt_ust_event *event)
 243 {
 244 }
 245 static inline
 246 struct ltt_ust_context *trace_ust_create_context(
 247                 struct lttng_event_context *ctx)
 248 {
 249         return NULL;
 250 }
 251 static inline
 252 int trace_ust_match_context(struct ltt_ust_context *uctx,
 253                 struct lttng_event_context *ctx)
 254 {
 255         return 0;
 256 }
 257 static inline struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
 258                 char *name, struct lttng_filter_bytecode *filter, int loglevel,
 259                 struct lttng_event_exclusion *exclusion)
 260 {
 261         return NULL;
 262 }
 263 static inline
 264 void trace_ust_delete_channel(struct lttng_ht *ht,
 265                 struct ltt_ust_channel *channel)
 266 {
 267         return;
 268 }
 269 static inline
 270 struct agent *trace_ust_find_agent(struct ltt_ust_session *session,
 271                 enum lttng_domain_type domain_type)
 272 {
 273         return NULL;
 274 }
 275
 276 #endif /* HAVE_LIBLTTNG_UST_CTL */
 277
 278 #endif /* _LTT_TRACE_UST_H */