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_ust_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         char name[LTTNG_UST_SYM_NAME_LEN];
  70         struct lttng_ust_channel_attr attr;
  71         struct lttng_ht *ctx;
  72         struct cds_list_head ctx_list;
  73         struct lttng_ht *events;
  74         struct lttng_ht_node_str node;
  75         uint64_t tracefile_size;
  76         uint64_t tracefile_count;
  77 };
  78
  79 /* UST domain global (LTTNG_DOMAIN_UST) */
  80 struct ltt_ust_domain_global {
  81         struct lttng_ht *channels;
  82         struct cds_list_head registry_buffer_uid_list;
  83 };
  84
  85 struct ust_pid_tracker_node {
  86         struct lttng_ht_node_ulong node;
  87 };
  88
  89 struct ust_pid_tracker {
  90         struct lttng_ht *ht;
  91 };
  92
  93 /* UST session */
  94 struct ltt_ust_session {
  95         uint64_t id;    /* Unique identifier of session */
  96         struct ltt_ust_domain_global domain_global;
  97         /* Hash table of agent indexed by agent domain. */
  98         struct lttng_ht *agents;
  99         /* UID/GID of the user owning the session */
 100         uid_t uid;
 101         gid_t gid;
 102         /* Is the session active meaning has is been started or stopped. */
 103         unsigned int active:1;
 104         /*
 105          * Two consumer_output object are needed where one is for the current
 106          * output object and the second one is the temporary object used to store
 107          * URI being set by the lttng_set_consumer_uri call. Once
 108          * lttng_enable_consumer is called, the two pointers are swapped.
 109          */
 110         struct consumer_output *consumer;
 111         struct consumer_output *tmp_consumer;
 112         /* Sequence number for filters so the tracer knows the ordering. */
 113         uint64_t filter_seq_num;
 114         /* This indicates which type of buffer this session is set for. */
 115         enum lttng_buffer_type buffer_type;
 116         /* If set to 1, the buffer_type can not be changed anymore. */
 117         int buffer_type_changed;
 118         /* For per UID buffer, every buffer reg object is kept of this session */
 119         struct cds_list_head buffer_reg_uid_list;
 120         /* Next channel ID available for a newly registered channel. */
 121         uint64_t next_channel_id;
 122         /* Once this value reaches UINT32_MAX, no more id can be allocated. */
 123         uint64_t used_channel_id;
 124         /* Tell or not if the session has to output the traces. */
 125         unsigned int output_traces;
 126         unsigned int snapshot_mode;
 127         unsigned int has_non_default_channel;
 128         unsigned int live_timer_interval;       /* usec */
 129
 130         /* Metadata channel attributes. */
 131         struct lttng_ust_channel_attr metadata_attr;
 132
 133         /*
 134          * Path where to keep the shared memory files.
 135          */
 136         char root_shm_path[PATH_MAX];
 137         char shm_path[PATH_MAX];
 138
 139         struct ust_pid_tracker pid_tracker;
 140 };
 141
 142 /*
 143  * Validate that the id has reached the maximum allowed or not.
 144  *
 145  * Return 0 if NOT else 1.
 146  */
 147 static inline int trace_ust_is_max_id(uint64_t id)
 148 {
 149         return (id == UINT64_MAX) ? 1 : 0;
 150 }
 151
 152 /*
 153  * Return next available channel id and increment the used counter. The
 154  * trace_ust_is_max_id function MUST be called before in order to validate if
 155  * the maximum number of IDs have been reached. If not, it is safe to call this
 156  * function.
 157  *
 158  * Return a unique channel ID. If max is reached, the used_channel_id counter
 159  * is returned.
 160  */
 161 static inline uint64_t trace_ust_get_next_chan_id(struct ltt_ust_session *s)
 162 {
 163         if (trace_ust_is_max_id(s->used_channel_id)) {
 164                 return s->used_channel_id;
 165         }
 166
 167         s->used_channel_id++;
 168         return s->next_channel_id++;
 169 }
 170
 171 #ifdef HAVE_LIBLTTNG_UST_CTL
 172
 173 int trace_ust_ht_match_event(struct cds_lfht_node *node, const void *_key);
 174 int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
 175                 const void *_key);
 176
 177 /*
 178  * Lookup functions. NULL is returned if not found.
 179  */
 180 struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
 181                 char *name, struct lttng_filter_bytecode *filter, int loglevel,
 182                 struct lttng_event_exclusion *exclusion);
 183 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 184                 char *name);
 185 struct agent *trace_ust_find_agent(struct ltt_ust_session *session,
 186                 enum lttng_domain_type domain_type);
 187
 188 /*
 189  * Create functions malloc() the data structure.
 190  */
 191 struct ltt_ust_session *trace_ust_create_session(uint64_t session_id);
 192 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *attr);
 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 {
 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, int loglevel,
 287                 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 */