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 "agent.h"
  31 #include "ust-ctl.h"
  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;
  37         const struct lttng_event_exclusion *exclusion;
  38 };
  39
  40 /* Context hash table nodes */
  41 struct ltt_ust_context {
  42         struct lttng_ust_context ctx;
  43         struct lttng_ht_node_ulong node;
  44         struct cds_list_head list;
  45 };
  46
  47 /* UST event */
  48 struct ltt_ust_event {
  49         unsigned int enabled;
  50         struct lttng_ust_event attr;
  51         struct lttng_ht_node_str node;
  52         char *filter_expression;
  53         struct lttng_ust_filter_bytecode *filter;
  54         struct lttng_event_exclusion *exclusion;
  55 };
  56
  57 /* UST channel */
  58 struct ltt_ust_channel {
  59         uint64_t id;    /* unique id per session. */
  60         unsigned int enabled;
  61         char name[LTTNG_UST_SYM_NAME_LEN];
  62         struct lttng_ust_channel_attr attr;
  63         struct lttng_ht *ctx;
  64         struct cds_list_head ctx_list;
  65         struct lttng_ht *events;
  66         struct lttng_ht_node_str node;
  67         uint64_t tracefile_size;
  68         uint64_t tracefile_count;
  69 };
  70
  71 /* UST domain global (LTTNG_DOMAIN_UST) */
  72 struct ltt_ust_domain_global {
  73         struct lttng_ht *channels;
  74         struct cds_list_head registry_buffer_uid_list;
  75 };
  76
  77 struct ust_pid_tracker_node {
  78         struct lttng_ht_node_ulong node;
  79 };
  80
  81 struct ust_pid_tracker {
  82         struct lttng_ht *ht;
  83 };
  84
  85 /* UST session */
  86 struct ltt_ust_session {
  87         uint64_t id;    /* Unique identifier of session */
  88         struct ltt_ust_domain_global domain_global;
  89         /* Hash table of agent indexed by agent domain. */
  90         struct lttng_ht *agents;
  91         /* UID/GID of the user owning the session */
  92         uid_t uid;
  93         gid_t gid;
  94         /* Is the session active meaning has is been started or stopped. */
  95         unsigned int active:1;
  96         /*
  97          * Two consumer_output object are needed where one is for the current
  98          * output object and the second one is the temporary object used to store
  99          * URI being set by the lttng_set_consumer_uri call. Once
 100          * lttng_enable_consumer is called, the two pointers are swapped.
 101          */
 102         struct consumer_output *consumer;
 103         struct consumer_output *tmp_consumer;
 104         /* Sequence number for filters so the tracer knows the ordering. */
 105         uint64_t filter_seq_num;
 106         /* This indicates which type of buffer this session is set for. */
 107         enum lttng_buffer_type buffer_type;
 108         /* If set to 1, the buffer_type can not be changed anymore. */
 109         int buffer_type_changed;
 110         /* For per UID buffer, every buffer reg object is kept of this session */
 111         struct cds_list_head buffer_reg_uid_list;
 112         /* Next channel ID available for a newly registered channel. */
 113         uint64_t next_channel_id;
 114         /* Once this value reaches UINT32_MAX, no more id can be allocated. */
 115         uint64_t used_channel_id;
 116         /* Tell or not if the session has to output the traces. */
 117         unsigned int output_traces;
 118         unsigned int snapshot_mode;
 119         unsigned int has_non_default_channel;
 120         unsigned int live_timer_interval;       /* usec */
 121
 122         /* Metadata channel attributes. */
 123         struct lttng_ust_channel_attr metadata_attr;
 124
 125         /*
 126          * Path where to keep the shared memory files.
 127          */
 128         char root_shm_path[PATH_MAX];
 129         char shm_path[PATH_MAX];
 130
 131         struct ust_pid_tracker pid_tracker;
 132 };
 133
 134 /*
 135  * Validate that the id has reached the maximum allowed or not.
 136  *
 137  * Return 0 if NOT else 1.
 138  */
 139 static inline int trace_ust_is_max_id(uint64_t id)
 140 {
 141         return (id == UINT64_MAX) ? 1 : 0;
 142 }
 143
 144 /*
 145  * Return next available channel id and increment the used counter. The
 146  * trace_ust_is_max_id function MUST be called before in order to validate if
 147  * the maximum number of IDs have been reached. If not, it is safe to call this
 148  * function.
 149  *
 150  * Return a unique channel ID. If max is reached, the used_channel_id counter
 151  * is returned.
 152  */
 153 static inline uint64_t trace_ust_get_next_chan_id(struct ltt_ust_session *s)
 154 {
 155         if (trace_ust_is_max_id(s->used_channel_id)) {
 156                 return s->used_channel_id;
 157         }
 158
 159         s->used_channel_id++;
 160         return s->next_channel_id++;
 161 }
 162
 163 #ifdef HAVE_LIBLTTNG_UST_CTL
 164
 165 int trace_ust_ht_match_event(struct cds_lfht_node *node, const void *_key);
 166 int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
 167                 const void *_key);
 168
 169 /*
 170  * Lookup functions. NULL is returned if not found.
 171  */
 172 struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
 173                 char *name, struct lttng_filter_bytecode *filter, int loglevel,
 174                 struct lttng_event_exclusion *exclusion);
 175 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 176                 char *name);
 177 struct agent *trace_ust_find_agent(struct ltt_ust_session *session,
 178                 enum lttng_domain_type domain_type);
 179
 180 /*
 181  * Create functions malloc() the data structure.
 182  */
 183 struct ltt_ust_session *trace_ust_create_session(uint64_t session_id);
 184 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *attr);
 185 struct ltt_ust_event *trace_ust_create_event(struct lttng_event *ev,
 186                 char *filter_expression,
 187                 struct lttng_filter_bytecode *filter,
 188                 struct lttng_event_exclusion *exclusion);
 189 struct ltt_ust_context *trace_ust_create_context(
 190                 struct lttng_event_context *ctx);
 191 int trace_ust_match_context(struct ltt_ust_context *uctx,
 192                 struct lttng_event_context *ctx);
 193 void trace_ust_delete_channel(struct lttng_ht *ht,
 194                 struct ltt_ust_channel *channel);
 195
 196 /*
 197  * Destroy functions free() the data structure and remove from linked list if
 198  * it's applies.
 199  */
 200 void trace_ust_destroy_session(struct ltt_ust_session *session);
 201 void trace_ust_destroy_channel(struct ltt_ust_channel *channel);
 202 void trace_ust_destroy_event(struct ltt_ust_event *event);
 203
 204 int trace_ust_track_pid(struct ltt_ust_session *session, int pid);
 205 int trace_ust_untrack_pid(struct ltt_ust_session *session, int pid);
 206
 207 int trace_ust_pid_tracker_lookup(struct ltt_ust_session *session, int pid);
 208
 209 ssize_t trace_ust_list_tracker_pids(struct ltt_ust_session *session,
 210                 int32_t **_pids);
 211
 212 #else /* HAVE_LIBLTTNG_UST_CTL */
 213
 214 static inline int trace_ust_ht_match_event(struct cds_lfht_node *node,
 215                 const void *_key)
 216 {
 217         return 0;
 218 }
 219 static inline int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
 220                 const void *_key)
 221 {
 222         return 0;
 223 }
 224 static inline
 225 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 226                 char *name)
 227 {
 228         return NULL;
 229 }
 230
 231 static inline
 232 struct ltt_ust_session *trace_ust_create_session(unsigned int session_id)
 233 {
 234         return NULL;
 235 }
 236 static inline
 237 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *attr)
 238 {
 239         return NULL;
 240 }
 241 static inline
 242 struct ltt_ust_event *trace_ust_create_event(struct lttng_event *ev,
 243                 const char *filter_expression,
 244                 struct lttng_filter_bytecode *filter,
 245                 struct lttng_event_exclusion *exclusion)
 246 {
 247         return NULL;
 248 }
 249 static inline
 250 void trace_ust_destroy_session(struct ltt_ust_session *session)
 251 {
 252 }
 253
 254 static inline
 255 void trace_ust_destroy_channel(struct ltt_ust_channel *channel)
 256 {
 257 }
 258
 259 static inline
 260 void trace_ust_destroy_event(struct ltt_ust_event *event)
 261 {
 262 }
 263 static inline
 264 struct ltt_ust_context *trace_ust_create_context(
 265                 struct lttng_event_context *ctx)
 266 {
 267         return NULL;
 268 }
 269 static inline
 270 int trace_ust_match_context(struct ltt_ust_context *uctx,
 271                 struct lttng_event_context *ctx)
 272 {
 273         return 0;
 274 }
 275 static inline struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
 276                 char *name, struct lttng_filter_bytecode *filter, int loglevel,
 277                 struct lttng_event_exclusion *exclusion)
 278 {
 279         return NULL;
 280 }
 281 static inline
 282 void trace_ust_delete_channel(struct lttng_ht *ht,
 283                 struct ltt_ust_channel *channel)
 284 {
 285         return;
 286 }
 287 static inline
 288 struct agent *trace_ust_find_agent(struct ltt_ust_session *session,
 289                 enum lttng_domain_type domain_type)
 290 {
 291         return NULL;
 292 }
 293 static inline
 294 int trace_ust_track_pid(struct ltt_ust_session *session, int pid)
 295 {
 296         return 0;
 297 }
 298 static inline
 299 int trace_ust_untrack_pid(struct ltt_ust_session *session, int pid)
 300 {
 301         return 0;
 302 }
 303 static inline
 304 int trace_ust_pid_tracker_lookup(struct ltt_ust_session *session, int pid)
 305 {
 306         return 0;
 307 }
 308 static inline
 309 ssize_t trace_ust_list_tracker_pids(struct ltt_ust_session *session,
 310                 int32_t **_pids)
 311 {
 312         return -1;
 313 }
 314 #endif /* HAVE_LIBLTTNG_UST_CTL */
 315
 316 #endif /* _LTT_TRACE_UST_H */