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;
  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         /*
 110          * Two consumer_output object are needed where one is for the current
 111          * output object and the second one is the temporary object used to store
 112          * URI being set by the lttng_set_consumer_uri call. Once
 113          * lttng_enable_consumer is called, the two pointers are swapped.
 114          */
 115         struct consumer_output *consumer;
 116         struct consumer_output *tmp_consumer;
 117         /* Sequence number for filters so the tracer knows the ordering. */
 118         uint64_t filter_seq_num;
 119         /* This indicates which type of buffer this session is set for. */
 120         enum lttng_buffer_type buffer_type;
 121         /* If set to 1, the buffer_type can not be changed anymore. */
 122         int buffer_type_changed;
 123         /* For per UID buffer, every buffer reg object is kept of this session */
 124         struct cds_list_head buffer_reg_uid_list;
 125         /* Next channel ID available for a newly registered channel. */
 126         uint64_t next_channel_id;
 127         /* Once this value reaches UINT32_MAX, no more id can be allocated. */
 128         uint64_t used_channel_id;
 129         /* Tell or not if the session has to output the traces. */
 130         unsigned int output_traces;
 131         unsigned int snapshot_mode;
 132         unsigned int has_non_default_channel;
 133         unsigned int live_timer_interval;       /* usec */
 134
 135         /* Metadata channel attributes. */
 136         struct lttng_ust_channel_attr metadata_attr;
 137
 138         /*
 139          * Path where to keep the shared memory files.
 140          */
 141         char root_shm_path[PATH_MAX];
 142         char shm_path[PATH_MAX];
 143
 144         struct ust_pid_tracker pid_tracker;
 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, int loglevel,
 187                 struct lttng_event_exclusion *exclusion);
 188 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 189                 char *name);
 190 struct agent *trace_ust_find_agent(struct ltt_ust_session *session,
 191                 enum lttng_domain_type domain_type);
 192
 193 /*
 194  * Create functions malloc() the data structure.
 195  */
 196 struct ltt_ust_session *trace_ust_create_session(uint64_t session_id);
 197 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *attr,
 198                 enum lttng_domain_type domain);
 199 struct ltt_ust_event *trace_ust_create_event(struct lttng_event *ev,
 200                 char *filter_expression,
 201                 struct lttng_filter_bytecode *filter,
 202                 struct lttng_event_exclusion *exclusion,
 203                 bool internal_event);
 204 struct ltt_ust_context *trace_ust_create_context(
 205                 struct lttng_event_context *ctx);
 206 int trace_ust_match_context(struct ltt_ust_context *uctx,
 207                 struct lttng_event_context *ctx);
 208 void trace_ust_delete_channel(struct lttng_ht *ht,
 209                 struct ltt_ust_channel *channel);
 210
 211 /*
 212  * Destroy functions free() the data structure and remove from linked list if
 213  * it's applies.
 214  */
 215 void trace_ust_destroy_session(struct ltt_ust_session *session);
 216 void trace_ust_destroy_channel(struct ltt_ust_channel *channel);
 217 void trace_ust_destroy_event(struct ltt_ust_event *event);
 218
 219 int trace_ust_track_pid(struct ltt_ust_session *session, int pid);
 220 int trace_ust_untrack_pid(struct ltt_ust_session *session, int pid);
 221
 222 int trace_ust_pid_tracker_lookup(struct ltt_ust_session *session, int pid);
 223
 224 ssize_t trace_ust_list_tracker_pids(struct ltt_ust_session *session,
 225                 int32_t **_pids);
 226
 227 #else /* HAVE_LIBLTTNG_UST_CTL */
 228
 229 static inline int trace_ust_ht_match_event(struct cds_lfht_node *node,
 230                 const void *_key)
 231 {
 232         return 0;
 233 }
 234 static inline int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
 235                 const void *_key)
 236 {
 237         return 0;
 238 }
 239 static inline
 240 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 241                 char *name)
 242 {
 243         return NULL;
 244 }
 245
 246 static inline
 247 struct ltt_ust_session *trace_ust_create_session(unsigned int session_id)
 248 {
 249         return NULL;
 250 }
 251 static inline
 252 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *attr,
 253                 enum lttng_domain_type domain)
 254 {
 255         return NULL;
 256 }
 257 static inline
 258 struct ltt_ust_event *trace_ust_create_event(struct lttng_event *ev,
 259                 const char *filter_expression,
 260                 struct lttng_filter_bytecode *filter,
 261                 struct lttng_event_exclusion *exclusion,
 262                 bool internal_event)
 263 {
 264         return NULL;
 265 }
 266 static inline
 267 void trace_ust_destroy_session(struct ltt_ust_session *session)
 268 {
 269 }
 270
 271 static inline
 272 void trace_ust_destroy_channel(struct ltt_ust_channel *channel)
 273 {
 274 }
 275
 276 static inline
 277 void trace_ust_destroy_event(struct ltt_ust_event *event)
 278 {
 279 }
 280 static inline
 281 struct ltt_ust_context *trace_ust_create_context(
 282                 struct lttng_event_context *ctx)
 283 {
 284         return NULL;
 285 }
 286 static inline
 287 int trace_ust_match_context(struct ltt_ust_context *uctx,
 288                 struct lttng_event_context *ctx)
 289 {
 290         return 0;
 291 }
 292 static inline struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
 293                 char *name, struct lttng_filter_bytecode *filter, int loglevel,
 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 */