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