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 <limits.h>
  22 #include <urcu/list.h>
  23
  24 #include <lttng/lttng.h>
  25 #include <common/hashtable/hashtable.h>
  26 #include <common/defaults.h>
  27
  28 #include "consumer.h"
  29 #include "ust-ctl.h"
  30
  31 struct agent;
  32
  33 struct ltt_ust_ht_key {
  34         const char *name;
  35         const struct lttng_filter_bytecode *filter;
  36         enum lttng_ust_loglevel_type loglevel_type;
  37         int loglevel_value;
  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                 enum lttng_ust_loglevel_type loglevel_type, int loglevel_value,
 181                 struct lttng_event_exclusion *exclusion);
 182 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 183                 char *name);
 184 struct agent *trace_ust_find_agent(struct ltt_ust_session *session,
 185                 enum lttng_domain_type domain_type);
 186
 187 /*
 188  * Create functions malloc() the data structure.
 189  */
 190 struct ltt_ust_session *trace_ust_create_session(uint64_t session_id);
 191 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *attr,
 192                 enum lttng_domain_type domain);
 193 struct ltt_ust_event *trace_ust_create_event(struct lttng_event *ev,
 194                 char *filter_expression,
 195                 struct lttng_filter_bytecode *filter,
 196                 struct lttng_event_exclusion *exclusion,
 197                 bool internal_event);
 198 struct ltt_ust_context *trace_ust_create_context(
 199                 struct lttng_event_context *ctx);
 200 int trace_ust_match_context(struct ltt_ust_context *uctx,
 201                 struct lttng_event_context *ctx);
 202 void trace_ust_delete_channel(struct lttng_ht *ht,
 203                 struct ltt_ust_channel *channel);
 204
 205 /*
 206  * Destroy functions free() the data structure and remove from linked list if
 207  * it's applies.
 208  */
 209 void trace_ust_destroy_session(struct ltt_ust_session *session);
 210 void trace_ust_destroy_channel(struct ltt_ust_channel *channel);
 211 void trace_ust_destroy_event(struct ltt_ust_event *event);
 212
 213 int trace_ust_track_pid(struct ltt_ust_session *session, int pid);
 214 int trace_ust_untrack_pid(struct ltt_ust_session *session, int pid);
 215
 216 int trace_ust_pid_tracker_lookup(struct ltt_ust_session *session, int pid);
 217
 218 ssize_t trace_ust_list_tracker_pids(struct ltt_ust_session *session,
 219                 int32_t **_pids);
 220
 221 #else /* HAVE_LIBLTTNG_UST_CTL */
 222
 223 static inline int trace_ust_ht_match_event(struct cds_lfht_node *node,
 224                 const void *_key)
 225 {
 226         return 0;
 227 }
 228 static inline int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
 229                 const void *_key)
 230 {
 231         return 0;
 232 }
 233 static inline
 234 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 235                 char *name)
 236 {
 237         return NULL;
 238 }
 239
 240 static inline
 241 struct ltt_ust_session *trace_ust_create_session(unsigned int session_id)
 242 {
 243         return NULL;
 244 }
 245 static inline
 246 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *attr,
 247                 enum lttng_domain_type domain)
 248 {
 249         return NULL;
 250 }
 251 static inline
 252 struct ltt_ust_event *trace_ust_create_event(struct lttng_event *ev,
 253                 const char *filter_expression,
 254                 struct lttng_filter_bytecode *filter,
 255                 struct lttng_event_exclusion *exclusion,
 256                 bool internal_event)
 257 {
 258         return NULL;
 259 }
 260 static inline
 261 void trace_ust_destroy_session(struct ltt_ust_session *session)
 262 {
 263 }
 264
 265 static inline
 266 void trace_ust_destroy_channel(struct ltt_ust_channel *channel)
 267 {
 268 }
 269
 270 static inline
 271 void trace_ust_destroy_event(struct ltt_ust_event *event)
 272 {
 273 }
 274 static inline
 275 struct ltt_ust_context *trace_ust_create_context(
 276                 struct lttng_event_context *ctx)
 277 {
 278         return NULL;
 279 }
 280 static inline
 281 int trace_ust_match_context(struct ltt_ust_context *uctx,
 282                 struct lttng_event_context *ctx)
 283 {
 284         return 0;
 285 }
 286 static inline
 287 struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
 288                 char *name, struct lttng_filter_bytecode *filter,
 289                 enum lttng_ust_loglevel_type loglevel_type, int loglevel_value,
 290                 struct lttng_event_exclusion *exclusion)
 291 {
 292         return NULL;
 293 }
 294 static inline
 295 void trace_ust_delete_channel(struct lttng_ht *ht,
 296                 struct ltt_ust_channel *channel)
 297 {
 298         return;
 299 }
 300 static inline
 301 struct agent *trace_ust_find_agent(struct ltt_ust_session *session,
 302                 enum lttng_domain_type domain_type)
 303 {
 304         return NULL;
 305 }
 306 static inline
 307 int trace_ust_track_pid(struct ltt_ust_session *session, int pid)
 308 {
 309         return 0;
 310 }
 311 static inline
 312 int trace_ust_untrack_pid(struct ltt_ust_session *session, int pid)
 313 {
 314         return 0;
 315 }
 316 static inline
 317 int trace_ust_pid_tracker_lookup(struct ltt_ust_session *session, int pid)
 318 {
 319         return 0;
 320 }
 321 static inline
 322 ssize_t trace_ust_list_tracker_pids(struct ltt_ust_session *session,
 323                 int32_t **_pids)
 324 {
 325         return -1;
 326 }
 327 #endif /* HAVE_LIBLTTNG_UST_CTL */
 328
 329 #endif /* _LTT_TRACE_UST_H */