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 "ust-ctl.h"
  31
  32 struct agent;
  33
  34 struct ltt_ust_ht_key {
  35         const char *name;
  36         const struct lttng_filter_bytecode *filter;
  37         enum lttng_ust_loglevel_type loglevel;
  38         const struct lttng_event_exclusion *exclusion;
  39 };
  40
  41 /* Context hash table nodes */
  42 struct ltt_ust_context {
  43         struct lttng_ust_context ctx;
  44         struct lttng_ht_node_ulong node;
  45         struct cds_list_head list;
  46 };
  47
  48 /* UST event */
  49 struct ltt_ust_event {
  50         unsigned int enabled;
  51         struct lttng_ust_event attr;
  52         struct lttng_ht_node_str node;
  53         char *filter_expression;
  54         struct lttng_ust_filter_bytecode *filter;
  55         struct lttng_event_exclusion *exclusion;
  56 };
  57
  58 /* UST channel */
  59 struct ltt_ust_channel {
  60         uint64_t id;    /* unique id per session. */
  61         unsigned int enabled;
  62         char name[LTTNG_UST_SYM_NAME_LEN];
  63         struct lttng_ust_channel_attr attr;
  64         struct lttng_ht *ctx;
  65         struct cds_list_head ctx_list;
  66         struct lttng_ht *events;
  67         struct lttng_ht_node_str node;
  68         uint64_t tracefile_size;
  69         uint64_t tracefile_count;
  70 };
  71
  72 /* UST domain global (LTTNG_DOMAIN_UST) */
  73 struct ltt_ust_domain_global {
  74         struct lttng_ht *channels;
  75         struct cds_list_head registry_buffer_uid_list;
  76 };
  77
  78 struct ust_pid_tracker_node {
  79         struct lttng_ht_node_ulong node;
  80 };
  81
  82 struct ust_pid_tracker {
  83         struct lttng_ht *ht;
  84 };
  85
  86 /* UST session */
  87 struct ltt_ust_session {
  88         uint64_t id;    /* Unique identifier of session */
  89         struct ltt_ust_domain_global domain_global;
  90         /* Hash table of agent indexed by agent domain. */
  91         struct lttng_ht *agents;
  92         /* UID/GID of the user owning the session */
  93         uid_t uid;
  94         gid_t gid;
  95         /* Is the session active meaning has is been started or stopped. */
  96         unsigned int active:1;
  97         /*
  98          * Two consumer_output object are needed where one is for the current
  99          * output object and the second one is the temporary object used to store
 100          * URI being set by the lttng_set_consumer_uri call. Once
 101          * lttng_enable_consumer is called, the two pointers are swapped.
 102          */
 103         struct consumer_output *consumer;
 104         struct consumer_output *tmp_consumer;
 105         /* Sequence number for filters so the tracer knows the ordering. */
 106         uint64_t filter_seq_num;
 107         /* This indicates which type of buffer this session is set for. */
 108         enum lttng_buffer_type buffer_type;
 109         /* If set to 1, the buffer_type can not be changed anymore. */
 110         int buffer_type_changed;
 111         /* For per UID buffer, every buffer reg object is kept of this session */
 112         struct cds_list_head buffer_reg_uid_list;
 113         /* Next channel ID available for a newly registered channel. */
 114         uint64_t next_channel_id;
 115         /* Once this value reaches UINT32_MAX, no more id can be allocated. */
 116         uint64_t used_channel_id;
 117         /* Tell or not if the session has to output the traces. */
 118         unsigned int output_traces;
 119         unsigned int snapshot_mode;
 120         unsigned int has_non_default_channel;
 121         unsigned int live_timer_interval;       /* usec */
 122
 123         /* Metadata channel attributes. */
 124         struct lttng_ust_channel_attr metadata_attr;
 125
 126         /*
 127          * Path where to keep the shared memory files.
 128          */
 129         char root_shm_path[PATH_MAX];
 130         char shm_path[PATH_MAX];
 131
 132         struct ust_pid_tracker pid_tracker;
 133 };
 134
 135 /*
 136  * Validate that the id has reached the maximum allowed or not.
 137  *
 138  * Return 0 if NOT else 1.
 139  */
 140 static inline int trace_ust_is_max_id(uint64_t id)
 141 {
 142         return (id == UINT64_MAX) ? 1 : 0;
 143 }
 144
 145 /*
 146  * Return next available channel id and increment the used counter. The
 147  * trace_ust_is_max_id function MUST be called before in order to validate if
 148  * the maximum number of IDs have been reached. If not, it is safe to call this
 149  * function.
 150  *
 151  * Return a unique channel ID. If max is reached, the used_channel_id counter
 152  * is returned.
 153  */
 154 static inline uint64_t trace_ust_get_next_chan_id(struct ltt_ust_session *s)
 155 {
 156         if (trace_ust_is_max_id(s->used_channel_id)) {
 157                 return s->used_channel_id;
 158         }
 159
 160         s->used_channel_id++;
 161         return s->next_channel_id++;
 162 }
 163
 164 #ifdef HAVE_LIBLTTNG_UST_CTL
 165
 166 int trace_ust_ht_match_event(struct cds_lfht_node *node, const void *_key);
 167 int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
 168                 const void *_key);
 169
 170 /*
 171  * Lookup functions. NULL is returned if not found.
 172  */
 173 struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
 174                 char *name, struct lttng_filter_bytecode *filter, int loglevel,
 175                 struct lttng_event_exclusion *exclusion);
 176 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 177                 char *name);
 178 struct agent *trace_ust_find_agent(struct ltt_ust_session *session,
 179                 enum lttng_domain_type domain_type);
 180
 181 /*
 182  * Create functions malloc() the data structure.
 183  */
 184 struct ltt_ust_session *trace_ust_create_session(uint64_t session_id);
 185 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *attr);
 186 struct ltt_ust_event *trace_ust_create_event(struct lttng_event *ev,
 187                 char *filter_expression,
 188                 struct lttng_filter_bytecode *filter,
 189                 struct lttng_event_exclusion *exclusion);
 190 struct ltt_ust_context *trace_ust_create_context(
 191                 struct lttng_event_context *ctx);
 192 int trace_ust_match_context(struct ltt_ust_context *uctx,
 193                 struct lttng_event_context *ctx);
 194 void trace_ust_delete_channel(struct lttng_ht *ht,
 195                 struct ltt_ust_channel *channel);
 196
 197 /*
 198  * Destroy functions free() the data structure and remove from linked list if
 199  * it's applies.
 200  */
 201 void trace_ust_destroy_session(struct ltt_ust_session *session);
 202 void trace_ust_destroy_channel(struct ltt_ust_channel *channel);
 203 void trace_ust_destroy_event(struct ltt_ust_event *event);
 204
 205 int trace_ust_track_pid(struct ltt_ust_session *session, int pid);
 206 int trace_ust_untrack_pid(struct ltt_ust_session *session, int pid);
 207
 208 int trace_ust_pid_tracker_lookup(struct ltt_ust_session *session, int pid);
 209
 210 ssize_t trace_ust_list_tracker_pids(struct ltt_ust_session *session,
 211                 int32_t **_pids);
 212
 213 #else /* HAVE_LIBLTTNG_UST_CTL */
 214
 215 static inline int trace_ust_ht_match_event(struct cds_lfht_node *node,
 216                 const void *_key)
 217 {
 218         return 0;
 219 }
 220 static inline int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
 221                 const void *_key)
 222 {
 223         return 0;
 224 }
 225 static inline
 226 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 227                 char *name)
 228 {
 229         return NULL;
 230 }
 231
 232 static inline
 233 struct ltt_ust_session *trace_ust_create_session(unsigned int session_id)
 234 {
 235         return NULL;
 236 }
 237 static inline
 238 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *attr)
 239 {
 240         return NULL;
 241 }
 242 static inline
 243 struct ltt_ust_event *trace_ust_create_event(struct lttng_event *ev,
 244                 const char *filter_expression,
 245                 struct lttng_filter_bytecode *filter,
 246                 struct lttng_event_exclusion *exclusion)
 247 {
 248         return NULL;
 249 }
 250 static inline
 251 void trace_ust_destroy_session(struct ltt_ust_session *session)
 252 {
 253 }
 254
 255 static inline
 256 void trace_ust_destroy_channel(struct ltt_ust_channel *channel)
 257 {
 258 }
 259
 260 static inline
 261 void trace_ust_destroy_event(struct ltt_ust_event *event)
 262 {
 263 }
 264 static inline
 265 struct ltt_ust_context *trace_ust_create_context(
 266                 struct lttng_event_context *ctx)
 267 {
 268         return NULL;
 269 }
 270 static inline
 271 int trace_ust_match_context(struct ltt_ust_context *uctx,
 272                 struct lttng_event_context *ctx)
 273 {
 274         return 0;
 275 }
 276 static inline struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
 277                 char *name, struct lttng_filter_bytecode *filter, int loglevel,
 278                 struct lttng_event_exclusion *exclusion)
 279 {
 280         return NULL;
 281 }
 282 static inline
 283 void trace_ust_delete_channel(struct lttng_ht *ht,
 284                 struct ltt_ust_channel *channel)
 285 {
 286         return;
 287 }
 288 static inline
 289 struct agent *trace_ust_find_agent(struct ltt_ust_session *session,
 290                 enum lttng_domain_type domain_type)
 291 {
 292         return NULL;
 293 }
 294 static inline
 295 int trace_ust_track_pid(struct ltt_ust_session *session, int pid)
 296 {
 297         return 0;
 298 }
 299 static inline
 300 int trace_ust_untrack_pid(struct ltt_ust_session *session, int pid)
 301 {
 302         return 0;
 303 }
 304 static inline
 305 int trace_ust_pid_tracker_lookup(struct ltt_ust_session *session, int pid)
 306 {
 307         return 0;
 308 }
 309 static inline
 310 ssize_t trace_ust_list_tracker_pids(struct ltt_ust_session *session,
 311                 int32_t **_pids)
 312 {
 313         return -1;
 314 }
 315 #endif /* HAVE_LIBLTTNG_UST_CTL */
 316
 317 #endif /* _LTT_TRACE_UST_H */