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