src/bin/lttng-sessiond/trace-ust.h

   1 /*
   2  * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
   3  * Copyright (C) 2016 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License, version 2 only,
   7  * as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along
  15  * with this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  17  */
  18
  19 #ifndef _LTT_TRACE_UST_H
  20 #define _LTT_TRACE_UST_H
  21
  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_type;
  38         int loglevel_value;
  39         const struct lttng_event_exclusion *exclusion;
  40 };
  41
  42 /* Context hash table nodes */
  43 struct ltt_ust_context {
  44         struct lttng_ust_context_attr ctx;
  45         struct lttng_ht_node_ulong node;
  46         struct cds_list_head list;
  47 };
  48
  49 /* UST event */
  50 struct ltt_ust_event {
  51         unsigned int enabled;
  52         struct lttng_ust_event attr;
  53         struct lttng_ht_node_str node;
  54         char *filter_expression;
  55         struct lttng_filter_bytecode *filter;
  56         struct lttng_event_exclusion *exclusion;
  57         /*
  58          * An internal event is an event which was created by the session daemon
  59          * through which, for example, events emitted in Agent domains are
  60          * "funelled". This is used to hide internal events from external
  61          * clients as they should never be modified by the external world.
  62          */
  63         bool internal;
  64 };
  65
  66 /* UST channel */
  67 struct ltt_ust_channel {
  68         uint64_t id;    /* unique id per session. */
  69         unsigned int enabled;
  70         /*
  71          * A UST channel can be part of a userspace sub-domain such as JUL,
  72          * Log4j, Python.
  73          */
  74         enum lttng_domain_type domain;
  75         char name[LTTNG_UST_SYM_NAME_LEN];
  76         struct lttng_ust_channel_attr attr;
  77         struct lttng_ht *ctx;
  78         struct cds_list_head ctx_list;
  79         struct lttng_ht *events;
  80         struct lttng_ht_node_str node;
  81         uint64_t tracefile_size;
  82         uint64_t tracefile_count;
  83 };
  84
  85 /* UST domain global (LTTNG_DOMAIN_UST) */
  86 struct ltt_ust_domain_global {
  87         struct lttng_ht *channels;
  88         struct cds_list_head registry_buffer_uid_list;
  89 };
  90
  91 struct ust_pid_tracker_node {
  92         struct lttng_ht_node_ulong node;
  93 };
  94
  95 struct ust_pid_tracker {
  96         struct lttng_ht *ht;
  97 };
  98
  99 /* UST session */
 100 struct ltt_ust_session {
 101         uint64_t id;    /* Unique identifier of session */
 102         struct ltt_ust_domain_global domain_global;
 103         /* Hash table of agent indexed by agent domain. */
 104         struct lttng_ht *agents;
 105         /* UID/GID of the user owning the session */
 106         uid_t uid;
 107         gid_t gid;
 108         /* Is the session active meaning has is been started or stopped. */
 109         unsigned int active:1;
 110         struct consumer_output *consumer;
 111         /* Sequence number for filters so the tracer knows the ordering. */
 112         uint64_t filter_seq_num;
 113         /* This indicates which type of buffer this session is set for. */
 114         enum lttng_buffer_type buffer_type;
 115         /* If set to 1, the buffer_type can not be changed anymore. */
 116         int buffer_type_changed;
 117         /* For per UID buffer, every buffer reg object is kept of this session */
 118         struct cds_list_head buffer_reg_uid_list;
 119         /* Next channel ID available for a newly registered channel. */
 120         uint64_t next_channel_id;
 121         /* Once this value reaches UINT32_MAX, no more id can be allocated. */
 122         uint64_t used_channel_id;
 123         /* Tell or not if the session has to output the traces. */
 124         unsigned int output_traces;
 125         unsigned int snapshot_mode;
 126         unsigned int has_non_default_channel;
 127         unsigned int live_timer_interval;       /* usec */
 128
 129         /* Metadata channel attributes. */
 130         struct lttng_ust_channel_attr metadata_attr;
 131
 132         /*
 133          * Path where to keep the shared memory files.
 134          */
 135         char root_shm_path[PATH_MAX];
 136         char shm_path[PATH_MAX];
 137
 138         struct ust_pid_tracker pid_tracker;
 139 };
 140
 141 /*
 142  * Validate that the id has reached the maximum allowed or not.
 143  *
 144  * Return 0 if NOT else 1.
 145  */
 146 static inline int trace_ust_is_max_id(uint64_t id)
 147 {
 148         return (id == UINT64_MAX) ? 1 : 0;
 149 }
 150
 151 /*
 152  * Return next available channel id and increment the used counter. The
 153  * trace_ust_is_max_id function MUST be called before in order to validate if
 154  * the maximum number of IDs have been reached. If not, it is safe to call this
 155  * function.
 156  *
 157  * Return a unique channel ID. If max is reached, the used_channel_id counter
 158  * is returned.
 159  */
 160 static inline uint64_t trace_ust_get_next_chan_id(struct ltt_ust_session *s)
 161 {
 162         if (trace_ust_is_max_id(s->used_channel_id)) {
 163                 return s->used_channel_id;
 164         }
 165
 166         s->used_channel_id++;
 167         return s->next_channel_id++;
 168 }
 169
 170 #ifdef HAVE_LIBLTTNG_UST_CTL
 171
 172 int trace_ust_ht_match_event(struct cds_lfht_node *node, const void *_key);
 173 int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
 174                 const void *_key);
 175
 176 /*
 177  * Lookup functions. NULL is returned if not found.
 178  */
 179 struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
 180                 char *name, struct lttng_filter_bytecode *filter,
 181                 enum lttng_ust_loglevel_type loglevel_type, int loglevel_value,
 182                 struct lttng_event_exclusion *exclusion);
 183 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 184                 char *name);
 185 struct agent *trace_ust_find_agent(struct ltt_ust_session *session,
 186                 enum lttng_domain_type domain_type);
 187
 188 /*
 189  * Create functions malloc() the data structure.
 190  */
 191 struct ltt_ust_session *trace_ust_create_session(uint64_t session_id);
 192 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *attr,
 193                 enum lttng_domain_type domain);
 194 struct ltt_ust_event *trace_ust_create_event(struct lttng_event *ev,
 195                 char *filter_expression,
 196                 struct lttng_filter_bytecode *filter,
 197                 struct lttng_event_exclusion *exclusion,
 198                 bool internal_event);
 199 struct ltt_ust_context *trace_ust_create_context(
 200                 struct lttng_event_context *ctx);
 201 int trace_ust_match_context(struct ltt_ust_context *uctx,
 202                 struct lttng_event_context *ctx);
 203 void trace_ust_delete_channel(struct lttng_ht *ht,
 204                 struct ltt_ust_channel *channel);
 205
 206 /*
 207  * Destroy functions free() the data structure and remove from linked list if
 208  * it's applies.
 209  */
 210 void trace_ust_destroy_session(struct ltt_ust_session *session);
 211 void trace_ust_destroy_channel(struct ltt_ust_channel *channel);
 212 void trace_ust_destroy_event(struct ltt_ust_event *event);
 213 void trace_ust_destroy_context(struct ltt_ust_context *ctx);
 214
 215 int trace_ust_track_pid(struct ltt_ust_session *session, int pid);
 216 int trace_ust_untrack_pid(struct ltt_ust_session *session, int pid);
 217
 218 int trace_ust_pid_tracker_lookup(struct ltt_ust_session *session, int pid);
 219
 220 ssize_t trace_ust_list_tracker_pids(struct ltt_ust_session *session,
 221                 int32_t **_pids);
 222
 223 #else /* HAVE_LIBLTTNG_UST_CTL */
 224
 225 static inline int trace_ust_ht_match_event(struct cds_lfht_node *node,
 226                 const void *_key)
 227 {
 228         return 0;
 229 }
 230 static inline int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
 231                 const void *_key)
 232 {
 233         return 0;
 234 }
 235 static inline
 236 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 237                 char *name)
 238 {
 239         return NULL;
 240 }
 241
 242 static inline
 243 struct ltt_ust_session *trace_ust_create_session(unsigned int session_id)
 244 {
 245         return NULL;
 246 }
 247 static inline
 248 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *attr,
 249                 enum lttng_domain_type domain)
 250 {
 251         return NULL;
 252 }
 253 static inline
 254 struct ltt_ust_event *trace_ust_create_event(struct lttng_event *ev,
 255                 const char *filter_expression,
 256                 struct lttng_filter_bytecode *filter,
 257                 struct lttng_event_exclusion *exclusion,
 258                 bool internal_event)
 259 {
 260         return NULL;
 261 }
 262 static inline
 263 void trace_ust_destroy_session(struct ltt_ust_session *session)
 264 {
 265 }
 266
 267 static inline
 268 void trace_ust_destroy_channel(struct ltt_ust_channel *channel)
 269 {
 270 }
 271
 272 static inline
 273 void trace_ust_destroy_event(struct ltt_ust_event *event)
 274 {
 275 }
 276 static inline
 277 struct ltt_ust_context *trace_ust_create_context(
 278                 struct lttng_event_context *ctx)
 279 {
 280         return NULL;
 281 }
 282 static inline
 283 int trace_ust_match_context(struct ltt_ust_context *uctx,
 284                 struct lttng_event_context *ctx)
 285 {
 286         return 0;
 287 }
 288 static inline
 289 struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
 290                 char *name, struct lttng_filter_bytecode *filter,
 291                 enum lttng_ust_loglevel_type loglevel_type, int loglevel_value,
 292                 struct lttng_event_exclusion *exclusion)
 293 {
 294         return NULL;
 295 }
 296 static inline
 297 void trace_ust_delete_channel(struct lttng_ht *ht,
 298                 struct ltt_ust_channel *channel)
 299 {
 300         return;
 301 }
 302 static inline
 303 struct agent *trace_ust_find_agent(struct ltt_ust_session *session,
 304                 enum lttng_domain_type domain_type)
 305 {
 306         return NULL;
 307 }
 308 static inline
 309 int trace_ust_track_pid(struct ltt_ust_session *session, int pid)
 310 {
 311         return 0;
 312 }
 313 static inline
 314 int trace_ust_untrack_pid(struct ltt_ust_session *session, int pid)
 315 {
 316         return 0;
 317 }
 318 static inline
 319 int trace_ust_pid_tracker_lookup(struct ltt_ust_session *session, int pid)
 320 {
 321         return 0;
 322 }
 323 static inline
 324 ssize_t trace_ust_list_tracker_pids(struct ltt_ust_session *session,
 325                 int32_t **_pids)
 326 {
 327         return -1;
 328 }
 329 #endif /* HAVE_LIBLTTNG_UST_CTL */
 330
 331 #endif /* _LTT_TRACE_UST_H */