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 "jul.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         struct lttng_ust_filter_bytecode *filter;
  53         const struct lttng_event_exclusion *exclusion;
  54 };
  55
  56 /* UST channel */
  57 struct ltt_ust_channel {
  58         uint64_t id;    /* unique id per session. */
  59         unsigned int enabled;
  60         char name[LTTNG_UST_SYM_NAME_LEN];
  61         struct lttng_ust_channel_attr attr;
  62         struct lttng_ht *ctx;
  63         struct cds_list_head ctx_list;
  64         struct lttng_ht *events;
  65         struct lttng_ht_node_str node;
  66         uint64_t tracefile_size;
  67         uint64_t tracefile_count;
  68 };
  69
  70 /* UST Metadata */
  71 struct ltt_ust_metadata {
  72         int handle;
  73         struct lttng_ust_object_data *obj;
  74         char pathname[PATH_MAX];              /* Trace file path name */
  75         struct lttng_ust_channel_attr attr;
  76         struct lttng_ust_object_data *stream_obj;
  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 /* UST session */
  86 struct ltt_ust_session {
  87         uint64_t id;    /* Unique identifier of session */
  88         int start_trace;
  89         struct ltt_ust_domain_global domain_global;
  90         struct jul_domain domain_jul;
  91         /* UID/GID of the user owning the session */
  92         uid_t uid;
  93         gid_t gid;
  94         /*
  95          * Two consumer_output object are needed where one is for the current
  96          * output object and the second one is the temporary object used to store
  97          * URI being set by the lttng_set_consumer_uri call. Once
  98          * lttng_enable_consumer is called, the two pointers are swapped.
  99          */
 100         struct consumer_output *consumer;
 101         struct consumer_output *tmp_consumer;
 102         /* Sequence number for filters so the tracer knows the ordering. */
 103         uint64_t filter_seq_num;
 104         /* This indicates which type of buffer this session is set for. */
 105         enum lttng_buffer_type buffer_type;
 106         /* If set to 1, the buffer_type can not be changed anymore. */
 107         int buffer_type_changed;
 108         /* For per UID buffer, every buffer reg object is kept of this session */
 109         struct cds_list_head buffer_reg_uid_list;
 110         /* Next channel ID available for a newly registered channel. */
 111         uint64_t next_channel_id;
 112         /* Once this value reaches UINT32_MAX, no more id can be allocated. */
 113         uint64_t used_channel_id;
 114         /* Tell or not if the session has to output the traces. */
 115         unsigned int output_traces;
 116         unsigned int snapshot_mode;
 117         unsigned int has_non_default_channel;
 118         unsigned int live_timer_interval;       /* usec */
 119 };
 120
 121 /*
 122  * Validate that the id has reached the maximum allowed or not.
 123  *
 124  * Return 0 if NOT else 1.
 125  */
 126 static inline int trace_ust_is_max_id(uint64_t id)
 127 {
 128         return (id == UINT64_MAX) ? 1 : 0;
 129 }
 130
 131 /*
 132  * Return next available channel id and increment the used counter. The
 133  * trace_ust_is_max_id function MUST be called before in order to validate if
 134  * the maximum number of IDs have been reached. If not, it is safe to call this
 135  * function.
 136  *
 137  * Return a unique channel ID. If max is reached, the used_channel_id counter
 138  * is returned.
 139  */
 140 static inline uint64_t trace_ust_get_next_chan_id(struct ltt_ust_session *s)
 141 {
 142         if (trace_ust_is_max_id(s->used_channel_id)) {
 143                 return s->used_channel_id;
 144         }
 145
 146         s->used_channel_id++;
 147         return s->next_channel_id++;
 148 }
 149
 150 #ifdef HAVE_LIBLTTNG_UST_CTL
 151
 152 int trace_ust_ht_match_event(struct cds_lfht_node *node, const void *_key);
 153 int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
 154                 const void *_key);
 155
 156 /*
 157  * Lookup functions. NULL is returned if not found.
 158  */
 159 struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
 160                 char *name, struct lttng_filter_bytecode *filter, int loglevel,
 161                 struct lttng_event_exclusion *exclusion);
 162 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 163                 char *name);
 164
 165 /*
 166  * Create functions malloc() the data structure.
 167  */
 168 struct ltt_ust_session *trace_ust_create_session(uint64_t session_id);
 169 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *attr);
 170 struct ltt_ust_event *trace_ust_create_event(struct lttng_event *ev,
 171                 struct lttng_filter_bytecode *filter,
 172                 struct lttng_event_exclusion *exclusion);
 173 struct ltt_ust_metadata *trace_ust_create_metadata(char *path);
 174 struct ltt_ust_context *trace_ust_create_context(
 175                 struct lttng_event_context *ctx);
 176 void trace_ust_delete_channel(struct lttng_ht *ht,
 177                 struct ltt_ust_channel *channel);
 178
 179 /*
 180  * Destroy functions free() the data structure and remove from linked list if
 181  * it's applies.
 182  */
 183 void trace_ust_destroy_session(struct ltt_ust_session *session);
 184 void trace_ust_destroy_metadata(struct ltt_ust_metadata *metadata);
 185 void trace_ust_destroy_channel(struct ltt_ust_channel *channel);
 186 void trace_ust_destroy_event(struct ltt_ust_event *event);
 187
 188 #else /* HAVE_LIBLTTNG_UST_CTL */
 189
 190 static inline int trace_ust_ht_match_event(struct cds_lfht_node *node,
 191                 const void *_key)
 192 {
 193         return 0;
 194 }
 195 static inline int trace_ust_ht_match_event_by_name(struct cds_lfht_node *node,
 196                 const void *_key)
 197 {
 198         return 0;
 199 }
 200 static inline
 201 struct ltt_ust_channel *trace_ust_find_channel_by_name(struct lttng_ht *ht,
 202                 char *name)
 203 {
 204         return NULL;
 205 }
 206
 207 static inline
 208 struct ltt_ust_session *trace_ust_create_session(unsigned int session_id)
 209 {
 210         return NULL;
 211 }
 212 static inline
 213 struct ltt_ust_channel *trace_ust_create_channel(struct lttng_channel *attr)
 214 {
 215         return NULL;
 216 }
 217 static inline
 218 struct ltt_ust_event *trace_ust_create_event(struct lttng_event *ev,
 219                 struct lttng_filter_bytecode *filter,
 220                 struct lttng_event_exclusion *exclusion)
 221 {
 222         return NULL;
 223 }
 224 static inline
 225 struct ltt_ust_metadata *trace_ust_create_metadata(char *path)
 226 {
 227         return NULL;
 228 }
 229
 230 static inline
 231 void trace_ust_destroy_session(struct ltt_ust_session *session)
 232 {
 233 }
 234
 235 static inline
 236 void trace_ust_destroy_metadata(struct ltt_ust_metadata *metadata)
 237 {
 238 }
 239
 240 static inline
 241 void trace_ust_destroy_channel(struct ltt_ust_channel *channel)
 242 {
 243 }
 244
 245 static inline
 246 void trace_ust_destroy_event(struct ltt_ust_event *event)
 247 {
 248 }
 249 static inline
 250 struct ltt_ust_context *trace_ust_create_context(
 251                 struct lttng_event_context *ctx)
 252 {
 253         return NULL;
 254 }
 255 static inline struct ltt_ust_event *trace_ust_find_event(struct lttng_ht *ht,
 256                 char *name, struct lttng_filter_bytecode *filter, int loglevel,
 257                 struct lttng_event_exclusion *exclusion)
 258 {
 259         return NULL;
 260 }
 261 static inline
 262 void trace_ust_delete_channel(struct lttng_ht *ht,
 263                 struct ltt_ust_channel *channel)
 264 {
 265         return;
 266 }
 267
 268 #endif /* HAVE_LIBLTTNG_UST_CTL */
 269
 270 #endif /* _LTT_TRACE_UST_H */