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