src/bin/lttng-sessiond/trace-kernel.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_KERNEL_H
  19 #define _LTT_TRACE_KERNEL_H
  20
  21 #include <urcu/list.h>
  22
  23 #include <lttng/lttng.h>
  24 #include <common/lttng-kernel.h>
  25
  26 #include "consumer.h"
  27
  28 /* Kernel event list */
  29 struct ltt_kernel_event_list {
  30         struct cds_list_head head;
  31 };
  32
  33 /* Channel stream list */
  34 struct ltt_kernel_stream_list {
  35         struct cds_list_head head;
  36 };
  37
  38 /* Channel list */
  39 struct ltt_kernel_channel_list {
  40         struct cds_list_head head;
  41 };
  42
  43 /* Kernel event */
  44 struct ltt_kernel_event {
  45         int fd;
  46         int enabled;
  47         /*
  48          * TODO: need internal representation to support more than a
  49          * single context.
  50          */
  51         struct lttng_kernel_context *ctx;
  52         struct lttng_kernel_event *event;
  53         struct cds_list_head list;
  54 };
  55
  56 /* Kernel channel */
  57 struct ltt_kernel_channel {
  58         int fd;
  59         int enabled;
  60         unsigned int stream_count;
  61         unsigned int event_count;
  62         /*
  63          * TODO: need internal representation to support more than a
  64          * single context.
  65          */
  66         struct lttng_kernel_context *ctx;
  67         struct lttng_channel *channel;
  68         struct ltt_kernel_event_list events_list;
  69         struct ltt_kernel_stream_list stream_list;
  70         struct cds_list_head list;
  71 };
  72
  73 /* Metadata */
  74 struct ltt_kernel_metadata {
  75         int fd;
  76         struct lttng_channel *conf;
  77 };
  78
  79 /* Channel stream */
  80 struct ltt_kernel_stream {
  81         int fd;
  82         int state;
  83         /* Format is %s_%d respectively channel name and CPU number. */
  84         char name[LTTNG_SYMBOL_NAME_LEN];
  85         struct cds_list_head list;
  86 };
  87
  88 /* Kernel session */
  89 struct ltt_kernel_session {
  90         int fd;
  91         int metadata_stream_fd;
  92         int consumer_fds_sent;
  93         int consumer_fd;
  94         unsigned int channel_count;
  95         unsigned int stream_count_global;
  96         char *trace_path;
  97         struct ltt_kernel_metadata *metadata;
  98         struct ltt_kernel_channel_list channel_list;
  99         /* UID/GID of the user owning the session */
 100         uid_t uid;
 101         gid_t gid;
 102         /*
 103          * Two consumer_output object are needed where one is needed for the
 104          * current output object and the second one is the temporary object used to
 105          * store URI being set by the lttng_set_consumer_uri call. Once
 106          * lttng_enable_consumer is called, the two pointers are swapped.
 107          */
 108         struct consumer_output *consumer;
 109         struct consumer_output *tmp_consumer;
 110 };
 111
 112 /*
 113  * Lookup functions. NULL is returned if not found.
 114  */
 115 struct ltt_kernel_event *trace_kernel_get_event_by_name(
 116                 char *name, struct ltt_kernel_channel *channel);
 117 struct ltt_kernel_channel *trace_kernel_get_channel_by_name(
 118                 char *name, struct ltt_kernel_session *session);
 119
 120 /*
 121  * Create functions malloc() the data structure.
 122  */
 123 struct ltt_kernel_session *trace_kernel_create_session(char *path);
 124 struct ltt_kernel_channel *trace_kernel_create_channel(struct lttng_channel *chan, char *path);
 125 struct ltt_kernel_event *trace_kernel_create_event(struct lttng_event *ev);
 126 struct ltt_kernel_metadata *trace_kernel_create_metadata(char *path);
 127 struct ltt_kernel_stream *trace_kernel_create_stream(const char *name,
 128                 unsigned int count);
 129
 130 /*
 131  * Destroy functions free() the data structure and remove from linked list if
 132  * it's applies.
 133  */
 134 void trace_kernel_destroy_session(struct ltt_kernel_session *session);
 135 void trace_kernel_destroy_metadata(struct ltt_kernel_metadata *metadata);
 136 void trace_kernel_destroy_channel(struct ltt_kernel_channel *channel);
 137 void trace_kernel_destroy_event(struct ltt_kernel_event *event);
 138 void trace_kernel_destroy_stream(struct ltt_kernel_stream *stream);
 139
 140 #endif /* _LTT_TRACE_KERNEL_H */