include/lttng/lttng.h

   1 /*
   2  * lttng.h
   3  *
   4  * Linux Trace Toolkit Control Library Header File
   5  *
   6  * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License
  10  * as published by the Free Software Foundation; either version 2
  11  * of the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  21  */
  22
  23 #ifndef _LTTNG_H
  24 #define _LTTNG_H
  25
  26 #include <asm/types.h>
  27 #include <stdint.h>
  28 #include <limits.h>
  29
  30 /* Default unix group name for tracing. */
  31 #define LTTNG_DEFAULT_TRACING_GROUP "tracing"
  32
  33 /* Environment variable to set session daemon binary path. */
  34 #define LTTNG_SESSIOND_PATH_ENV "LTTNG_SESSIOND_PATH"
  35
  36 /*
  37  * Event symbol length.
  38  */
  39 #define LTTNG_SYMBOL_NAME_LEN 128
  40
  41 enum lttng_event_type {
  42         LTTNG_EVENT_TRACEPOINTS,
  43         LTTNG_EVENT_KPROBES,
  44         LTTNG_EVENT_FUNCTION,
  45 };
  46
  47 /*
  48  * Either addr is used or symbol_name and offset.
  49  */
  50 struct lttng_event_kprobe_attr {
  51         uint64_t addr;
  52
  53         uint64_t offset;
  54         char symbol_name[LTTNG_SYMBOL_NAME_LEN];
  55 };
  56
  57 /*
  58  * Function tracer
  59  */
  60 struct lttng_event_function_attr {
  61         char symbol_name[LTTNG_SYMBOL_NAME_LEN];
  62 };
  63
  64 /*
  65  * Generic lttng event
  66  */
  67 struct lttng_event {
  68         char name[LTTNG_SYMBOL_NAME_LEN];
  69         enum lttng_event_type type;
  70         /* Per event type configuration */
  71         union {
  72                 struct lttng_event_kprobe_attr kprobe;
  73                 struct lttng_event_function_attr ftrace;
  74         } attr;
  75 };
  76
  77 /* Tracer channel attributes */
  78 struct lttng_channel_attr {
  79         int overwrite;                        /* 1: overwrite, 0: discard */
  80         uint64_t subbuf_size;                      /* bytes */
  81         uint64_t num_subbuf;                       /* power of 2 */
  82         unsigned int switch_timer_interval;   /* usec */
  83         unsigned int read_timer_interval;     /* usec */
  84 };
  85
  86 /*
  87  * Basic session information.
  88  */
  89 struct lttng_session {
  90         char name[NAME_MAX];
  91         char path[PATH_MAX];
  92 };
  93
  94 /* Channel information structure */
  95 struct lttng_channel {
  96         char name[NAME_MAX];
  97         struct lttng_channel_attr attr;
  98 };
  99
 100 /*
 101  * Session daemon control
 102  */
 103 extern int lttng_connect_sessiond(void);
 104
 105 extern int lttng_create_session(char *name, char *path);
 106
 107 extern int lttng_destroy_session(char *name);
 108
 109 extern int lttng_disconnect_sessiond(void);
 110
 111 /* Return an allocated array of lttng_session */
 112 extern int lttng_list_sessions(struct lttng_session **sessions);
 113
 114 extern int lttng_session_daemon_alive(void);
 115
 116 /* Set tracing group for the current execution */
 117 extern int lttng_set_tracing_group(const char *name);
 118
 119 extern void lttng_set_session_name(char *name);
 120
 121 extern const char *lttng_get_readable_code(int code);
 122
 123 extern int lttng_start_tracing(char *session_name);
 124
 125 extern int lttng_stop_tracing(char *session_name);
 126
 127 //extern int lttng_ust_list_traceable_apps(pid_t **pids);
 128
 129 /*
 130  * LTTng Kernel tracer control
 131  */
 132 extern int lttng_kernel_create_channel(struct lttng_channel *chan);
 133
 134 extern int lttng_kernel_enable_event(struct lttng_event *ev, char *channel_name);
 135
 136 extern int lttng_kernel_enable_channel(char *name);
 137
 138 extern int lttng_kernel_disable_event(char *name, char *channel_name);
 139
 140 extern int lttng_kernel_disable_channel(char *name);
 141
 142 extern int lttng_kernel_list_events(char **event_list);
 143
 144 /*
 145  * LTTng User-space tracer control
 146  */
 147
 148 #endif /* _LTTNG_H */