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