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 "lttng-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         uint64_t per_pid_closed_app_discarded;
  84         uint64_t per_pid_closed_app_lost;
  85         uint64_t monitor_timer_interval;
  86 };
  87
  88 /* UST domain global (LTTNG_DOMAIN_UST) */
  89 struct ltt_ust_domain_global {
  90         struct lttng_ht *channels;
  91         struct cds_list_head registry_buffer_uid_list;
  92 };
  93
  94 struct ust_pid_tracker_node {
  95         struct lttng_ht_node_ulong node;
  96 };
  97
  98 struct ust_pid_tracker {
  99         struct lttng_ht *ht;
 100 };
 101
 102 /* UST session */
 103 struct ltt_ust_session {
 104         uint64_t id;    /* Unique identifier of session */
 105         struct ltt_ust_domain_global domain_global;
 106         /* Hash table of agent indexed by agent domain. */
 107         struct lttng_ht *agents;
 108         /* UID/GID of the user owning the session */
 109         uid_t uid;
 110         gid_t gid;
 111         /* Is the session active meaning has is been started or stopped. */
 112         unsigned int active:1;
 113         struct consumer_output *consumer;
 114         /* Sequence number for filters so the tracer knows the ordering. */
 115         uint64_t filter_seq_num;
 116         /* This indicates which type of buffer this session is set for. */
 117         enum lttng_buffer_type buffer_type;
 118         /* If set to 1, the buffer_type can not be changed anymore. */
 119         int buffer_type_changed;
 120         /* For per UID buffer, every buffer reg object is kept of this session */
 121         struct cds_list_head buffer_reg_uid_list;
 122         /* Next channel ID available for a newly registered channel. */
 123         uint64_t next_channel_id;
 124         /* Once this value reaches UINT32_MAX, no more id can be allocated. */
 125         uint64_t used_channel_id;
 126         /* Tell or not if the session has to output the traces. */
 127         unsigned int output_traces;
 128         unsigned int snapshot_mode;
 129         unsigned int has_non_default_channel;
 130         unsigned int live_timer_interval;       /* usec */
 131
 132         /* Metadata channel attributes. */
 133         struct lttng_ust_channel_attr metadata_attr;
 134
 135         /*
 136          * Path where to keep the shared memory files.
 137          */
 138         char root_shm_path[PATH_MAX];
 139         char shm_path[PATH_MAX];
 140
 141         struct ust_pid_tracker pid_tracker;
 142
 143         /* Current trace chunk of the ltt_session. */
 144         struct lttng_trace_chunk *current_trace_chunk;
 145 };
 146
 147 /*
 148  * Validate that the id has reached the maximum allowed or not.
 149  *
 150  * Return 0 if NOT else 1.
 151  */
 152 static inline int trace_ust_is_max_id(uint64_t id)
 153 {
 154         return (id == UINT64_MAX) ? 1 : 0;
 155 }
 156
 157 /*
 158  * Return next available channel id and increment the used counter. The
 159  * trace_ust_is_max_id function MUST be called before in order to validate if
 160  * the maximum number of IDs have been reached. If not, it is safe to call this
 161  * function.
 162  *
 163  * Return a unique channel ID. If max is reached, the used_channel_id counter
 164  * is returned.
 165  */
 166 static inline uint64_t trace_ust_get_next_chan_id(struct ltt_ust_session *s)
 167 {
 168         if (trace_ust_is_max_id(s->used_channel_id)) {
 169                 return s->used_channel_id;
 170         }
 171
 172         s->used_channel_id++;
 173         return s->next_channel_id++;
 174 }
 175
 176 #ifdef HAVE_LIBLTTNG_UST_CTL
 177
 178 int trace_ust_ht_match_event(struct cds_lfht_node *node, const void *_key);
 179 int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
 180                 const void *_key);
 181
 182 /*
 183  * Lookup functions. NULL is returned if not found.
 184  */
 185 struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
 186                 char *name, struct lttng_filter_bytecode *filter,
 187                 enum lttng_ust_loglevel_type loglevel_type, int loglevel_value,
 188                 struct lttng_event_exclusion *exclusion);
 189 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 190                 const char *name);
 191 struct agent *trace_ust_find_agent(struct ltt_ust_session *session,
 192                 enum lttng_domain_type domain_type);
 193
 194 /*
 195  * Create functions malloc() the data structure.
 196  */
 197 struct ltt_ust_session *trace_ust_create_session(uint64_t session_id);
 198 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *attr,
 199                 enum lttng_domain_type domain);
 200 enum lttng_error_code trace_ust_create_event(struct lttng_event *ev,
 201                 char *filter_expression,
 202                 struct lttng_filter_bytecode *filter,
 203                 struct lttng_event_exclusion *exclusion,
 204                 bool internal_event, struct ltt_ust_event **ust_event);
 205 struct ltt_ust_context *trace_ust_create_context(
 206                 const struct lttng_event_context *ctx);
 207 int trace_ust_match_context(const struct ltt_ust_context *uctx,
 208                 const struct lttng_event_context *ctx);
 209 void trace_ust_delete_channel(struct lttng_ht *ht,
 210                 struct ltt_ust_channel *channel);
 211
 212 /*
 213  * Destroy functions free() the data structure and remove from linked list if
 214  * it's applies.
 215  */
 216 void trace_ust_destroy_session(struct ltt_ust_session *session);
 217 void trace_ust_destroy_channel(struct ltt_ust_channel *channel);
 218 void trace_ust_destroy_event(struct ltt_ust_event *event);
 219 void trace_ust_destroy_context(struct ltt_ust_context *ctx);
 220 void trace_ust_free_session(struct ltt_ust_session *session);
 221
 222 int trace_ust_track_pid(struct ltt_ust_session *session, int pid);
 223 int trace_ust_untrack_pid(struct ltt_ust_session *session, int pid);
 224
 225 int trace_ust_pid_tracker_lookup(struct ltt_ust_session *session, int pid);
 226
 227 ssize_t trace_ust_list_tracker_pids(struct ltt_ust_session *session,
 228                 int32_t **_pids);
 229
 230 #else /* HAVE_LIBLTTNG_UST_CTL */
 231
 232 static inline int trace_ust_ht_match_event(struct cds_lfht_node *node,
 233                 const void *_key)
 234 {
 235         return 0;
 236 }
 237 static inline int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
 238                 const void *_key)
 239 {
 240         return 0;
 241 }
 242 static inline
 243 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 244                 const char *name)
 245 {
 246         return NULL;
 247 }
 248
 249 static inline
 250 struct ltt_ust_session *trace_ust_create_session(unsigned int session_id)
 251 {
 252         return NULL;
 253 }
 254 static inline
 255 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *attr,
 256                 enum lttng_domain_type domain)
 257 {
 258         return NULL;
 259 }
 260 static inline
 261 enum lttng_error_code trace_ust_create_event(struct lttng_event *ev,
 262                 const char *filter_expression,
 263                 struct lttng_filter_bytecode *filter,
 264                 struct lttng_event_exclusion *exclusion,
 265                 bool internal_event, struct ltt_ust_event **ust_event)
 266 {
 267         return LTTNG_ERR_NO_UST;
 268 }
 269 static inline
 270 void trace_ust_destroy_session(struct ltt_ust_session *session)
 271 {
 272 }
 273
 274 static inline
 275 void trace_ust_destroy_channel(struct ltt_ust_channel *channel)
 276 {
 277 }
 278
 279 static inline
 280 void trace_ust_destroy_event(struct ltt_ust_event *event)
 281 {
 282 }
 283
 284 static inline
 285 void trace_ust_free_session(struct ltt_ust_session *session)
 286 {
 287 }
 288
 289 static inline
 290 struct ltt_ust_context *trace_ust_create_context(
 291                 const struct lttng_event_context *ctx)
 292 {
 293         return NULL;
 294 }
 295 static inline
 296 int trace_ust_match_context(const struct ltt_ust_context *uctx,
 297                 const struct lttng_event_context *ctx)
 298 {
 299         return 0;
 300 }
 301 static inline
 302 struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
 303                 char *name, struct lttng_filter_bytecode *filter,
 304                 enum lttng_ust_loglevel_type loglevel_type, int loglevel_value,
 305                 struct lttng_event_exclusion *exclusion)
 306 {
 307         return NULL;
 308 }
 309 static inline
 310 void trace_ust_delete_channel(struct lttng_ht *ht,
 311                 struct ltt_ust_channel *channel)
 312 {
 313         return;
 314 }
 315 static inline
 316 struct agent *trace_ust_find_agent(struct ltt_ust_session *session,
 317                 enum lttng_domain_type domain_type)
 318 {
 319         return NULL;
 320 }
 321 static inline
 322 int trace_ust_track_pid(struct ltt_ust_session *session, int pid)
 323 {
 324         return 0;
 325 }
 326 static inline
 327 int trace_ust_untrack_pid(struct ltt_ust_session *session, int pid)
 328 {
 329         return 0;
 330 }
 331 static inline
 332 int trace_ust_pid_tracker_lookup(struct ltt_ust_session *session, int pid)
 333 {
 334         return 0;
 335 }
 336 static inline
 337 ssize_t trace_ust_list_tracker_pids(struct ltt_ust_session *session,
 338                 int32_t **_pids)
 339 {
 340         return -1;
 341 }
 342 #endif /* HAVE_LIBLTTNG_UST_CTL */
 343
 344 #endif /* _LTT_TRACE_UST_H */