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         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
 144 /*
 145  * Validate that the id has reached the maximum allowed or not.
 146  *
 147  * Return 0 if NOT else 1.
 148  */
 149 static inline int trace_ust_is_max_id(uint64_t id)
 150 {
 151         return (id == UINT64_MAX) ? 1 : 0;
 152 }
 153
 154 /*
 155  * Return next available channel id and increment the used counter. The
 156  * trace_ust_is_max_id function MUST be called before in order to validate if
 157  * the maximum number of IDs have been reached. If not, it is safe to call this
 158  * function.
 159  *
 160  * Return a unique channel ID. If max is reached, the used_channel_id counter
 161  * is returned.
 162  */
 163 static inline uint64_t trace_ust_get_next_chan_id(struct ltt_ust_session *s)
 164 {
 165         if (trace_ust_is_max_id(s->used_channel_id)) {
 166                 return s->used_channel_id;
 167         }
 168
 169         s->used_channel_id++;
 170         return s->next_channel_id++;
 171 }
 172
 173 #ifdef HAVE_LIBLTTNG_UST_CTL
 174
 175 int trace_ust_ht_match_event(struct cds_lfht_node *node, const void *_key);
 176 int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
 177                 const void *_key);
 178
 179 /*
 180  * Lookup functions. NULL is returned if not found.
 181  */
 182 struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
 183                 char *name, struct lttng_filter_bytecode *filter,
 184                 enum lttng_ust_loglevel_type loglevel_type, int loglevel_value,
 185                 struct lttng_event_exclusion *exclusion);
 186 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 187                 char *name);
 188 struct agent *trace_ust_find_agent(struct ltt_ust_session *session,
 189                 enum lttng_domain_type domain_type);
 190
 191 /*
 192  * Create functions malloc() the data structure.
 193  */
 194 struct ltt_ust_session *trace_ust_create_session(uint64_t session_id);
 195 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *attr,
 196                 enum lttng_domain_type domain);
 197 enum lttng_error_code trace_ust_create_event(struct lttng_event *ev,
 198                 char *filter_expression,
 199                 struct lttng_filter_bytecode *filter,
 200                 struct lttng_event_exclusion *exclusion,
 201                 bool internal_event, struct ltt_ust_event **ust_event);
 202 struct ltt_ust_context *trace_ust_create_context(
 203                 struct lttng_event_context *ctx);
 204 int trace_ust_match_context(struct ltt_ust_context *uctx,
 205                 struct lttng_event_context *ctx);
 206 void trace_ust_delete_channel(struct lttng_ht *ht,
 207                 struct ltt_ust_channel *channel);
 208
 209 /*
 210  * Destroy functions free() the data structure and remove from linked list if
 211  * it's applies.
 212  */
 213 void trace_ust_destroy_session(struct ltt_ust_session *session);
 214 void trace_ust_destroy_channel(struct ltt_ust_channel *channel);
 215 void trace_ust_destroy_event(struct ltt_ust_event *event);
 216 void trace_ust_destroy_context(struct ltt_ust_context *ctx);
 217
 218 int trace_ust_track_pid(struct ltt_ust_session *session, int pid);
 219 int trace_ust_untrack_pid(struct ltt_ust_session *session, int pid);
 220
 221 int trace_ust_pid_tracker_lookup(struct ltt_ust_session *session, int pid);
 222
 223 ssize_t trace_ust_list_tracker_pids(struct ltt_ust_session *session,
 224                 int32_t **_pids);
 225
 226 #else /* HAVE_LIBLTTNG_UST_CTL */
 227
 228 static inline int trace_ust_ht_match_event(struct cds_lfht_node *node,
 229                 const void *_key)
 230 {
 231         return 0;
 232 }
 233 static inline int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
 234                 const void *_key)
 235 {
 236         return 0;
 237 }
 238 static inline
 239 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 240                 char *name)
 241 {
 242         return NULL;
 243 }
 244
 245 static inline
 246 struct ltt_ust_session *trace_ust_create_session(unsigned int session_id)
 247 {
 248         return NULL;
 249 }
 250 static inline
 251 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *attr,
 252                 enum lttng_domain_type domain)
 253 {
 254         return NULL;
 255 }
 256 static inline
 257 enum lttng_error_code trace_ust_create_event(struct lttng_event *ev,
 258                 const char *filter_expression,
 259                 struct lttng_filter_bytecode *filter,
 260                 struct lttng_event_exclusion *exclusion,
 261                 bool internal_event, struct ltt_ust_event **ust_event)
 262 {
 263         return LTTNG_ERR_NO_UST;
 264 }
 265 static inline
 266 void trace_ust_destroy_session(struct ltt_ust_session *session)
 267 {
 268 }
 269
 270 static inline
 271 void trace_ust_destroy_channel(struct ltt_ust_channel *channel)
 272 {
 273 }
 274
 275 static inline
 276 void trace_ust_destroy_event(struct ltt_ust_event *event)
 277 {
 278 }
 279 static inline
 280 struct ltt_ust_context *trace_ust_create_context(
 281                 struct lttng_event_context *ctx)
 282 {
 283         return NULL;
 284 }
 285 static inline
 286 int trace_ust_match_context(struct ltt_ust_context *uctx,
 287                 struct lttng_event_context *ctx)
 288 {
 289         return 0;
 290 }
 291 static inline
 292 struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
 293                 char *name, struct lttng_filter_bytecode *filter,
 294                 enum lttng_ust_loglevel_type loglevel_type, int loglevel_value,
 295                 struct lttng_event_exclusion *exclusion)
 296 {
 297         return NULL;
 298 }
 299 static inline
 300 void trace_ust_delete_channel(struct lttng_ht *ht,
 301                 struct ltt_ust_channel *channel)
 302 {
 303         return;
 304 }
 305 static inline
 306 struct agent *trace_ust_find_agent(struct ltt_ust_session *session,
 307                 enum lttng_domain_type domain_type)
 308 {
 309         return NULL;
 310 }
 311 static inline
 312 int trace_ust_track_pid(struct ltt_ust_session *session, int pid)
 313 {
 314         return 0;
 315 }
 316 static inline
 317 int trace_ust_untrack_pid(struct ltt_ust_session *session, int pid)
 318 {
 319         return 0;
 320 }
 321 static inline
 322 int trace_ust_pid_tracker_lookup(struct ltt_ust_session *session, int pid)
 323 {
 324         return 0;
 325 }
 326 static inline
 327 ssize_t trace_ust_list_tracker_pids(struct ltt_ust_session *session,
 328                 int32_t **_pids)
 329 {
 330         return -1;
 331 }
 332 #endif /* HAVE_LIBLTTNG_UST_CTL */
 333
 334 #endif /* _LTT_TRACE_UST_H */