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 #include <common/lttng-kernel-old.h>
  26 #include <common/defaults.h>
  27
  28 #include "consumer.h"
  29
  30 /* Kernel event list */
  31 struct ltt_kernel_event_list {
  32         struct cds_list_head head;
  33 };
  34
  35 /* Channel stream list */
  36 struct ltt_kernel_stream_list {
  37         struct cds_list_head head;
  38 };
  39
  40 /* Channel list */
  41 struct ltt_kernel_channel_list {
  42         struct cds_list_head head;
  43 };
  44
  45 /* Kernel event */
  46 struct ltt_kernel_event {
  47         int fd;
  48         int enabled;
  49         struct lttng_kernel_event *event;
  50         struct cds_list_head list;
  51 };
  52
  53 /* Kernel channel */
  54 struct ltt_kernel_channel {
  55         int fd;
  56         int enabled;
  57         unsigned int stream_count;
  58         unsigned int event_count;
  59         /*
  60          * TODO: need internal representation to support more than a
  61          * single context.
  62          */
  63         struct lttng_kernel_context *ctx;
  64         struct lttng_channel *channel;
  65         struct ltt_kernel_event_list events_list;
  66         struct ltt_kernel_stream_list stream_list;
  67         struct cds_list_head list;
  68 };
  69
  70 /* Metadata */
  71 struct ltt_kernel_metadata {
  72         int fd;
  73         struct lttng_channel *conf;
  74 };
  75
  76 /* Channel stream */
  77 struct ltt_kernel_stream {
  78         int fd;
  79         int state;
  80         /* Format is %s_%d respectively channel name and CPU number. */
  81         char name[DEFAULT_STREAM_NAME_LEN];
  82         struct cds_list_head list;
  83 };
  84
  85 /* Kernel session */
  86 struct ltt_kernel_session {
  87         int fd;
  88         int metadata_stream_fd;
  89         int consumer_fds_sent;
  90         unsigned int channel_count;
  91         unsigned int stream_count_global;
  92         char *trace_path;
  93         struct ltt_kernel_metadata *metadata;
  94         struct ltt_kernel_channel_list channel_list;
  95         /* UID/GID of the user owning the session */
  96         uid_t uid;
  97         gid_t gid;
  98         /*
  99          * Two consumer_output object are needed where one is needed for the
 100          * current output object and the second one is the temporary object used to
 101          * store URI being set by the lttng_set_consumer_uri call. Once
 102          * lttng_enable_consumer is called, the two pointers are swapped.
 103          */
 104         struct consumer_output *consumer;
 105         struct consumer_output *tmp_consumer;
 106         /* Tracing session id */
 107         unsigned int id;
 108         /* Session is started and active */
 109         unsigned int started;
 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(void);
 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 */