ltt-events.h

   1 #ifndef _LTT_EVENTS_H
   2 #define _LTT_EVENTS_H
   3
   4 /*
   5  * ltt-events.h
   6  *
   7  * Copyright 2010 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   8  *
   9  * Holds LTTng per-session event registry.
  10  */
  11
  12 #include <linux/list.h>
  13 #include "ltt-debugfs-abi.h"
  14
  15 struct ltt_channel;
  16 struct ltt_session;
  17 struct lib_ring_buffer_ctx;
  18
  19 /*
  20  * ltt_event structure is referred to by the tracing fast path. It must be
  21  * kept small.
  22  */
  23 struct ltt_event {
  24         unsigned int id;
  25         struct ltt_channel *chan;
  26         void *probe;
  27         void *filter;
  28         char *name;
  29         enum instrum_type itype;
  30         struct list_head list;          /* Event list */
  31 };
  32
  33 struct ltt_channel_ops {
  34         struct channel *(*channel_create)(const char *name,
  35                                 struct ltt_session *session,
  36                                 void *buf_addr,
  37                                 size_t subbuf_size, size_t num_subbuf,
  38                                 unsigned int switch_timer_interval,
  39                                 unsigned int read_timer_interval);
  40         void (*channel_destroy)(struct channel *chan);
  41         struct lib_ring_buffer *(*buffer_read_open)(struct channel *chan);
  42         void (*buffer_read_close)(struct lib_ring_buffer *buf);
  43         int (*event_reserve)(struct lib_ring_buffer_ctx *ctx);
  44         void (*event_commit)(struct lib_ring_buffer_ctx *ctx);
  45         void (*event_write)(struct lib_ring_buffer_ctx *ctx, const void *src,
  46                             size_t len);
  47 };
  48
  49 struct ltt_channel {
  50         struct channel *chan;           /* Channel buffers */
  51         /* Event ID management */
  52         struct ltt_session *session;
  53         struct file *file;              /* File associated to channel */
  54         unsigned int free_event_id;     /* Next event ID to allocate */
  55         struct list_head list;          /* Channel list */
  56         wait_queue_head_t notify_wait;  /* Channel addition notif. waitqueue */
  57         struct ltt_channel_ops *ops;
  58 };
  59
  60 struct ltt_session {
  61         int active;                     /* Is trace session active ? */
  62         struct file *file;              /* File associated to session */
  63         struct list_head chan;          /* Channel list head */
  64         struct list_head events;        /* Event list head */
  65         struct list_head list;          /* Session list */
  66 };
  67
  68 struct ltt_transport {
  69         char *name;
  70         struct module *owner;
  71         struct list_head node;
  72         struct ltt_channel_ops ops;
  73 };
  74
  75 struct ltt_session *ltt_session_create(void);
  76 int ltt_session_start(struct ltt_session *session);
  77 int ltt_session_stop(struct ltt_session *session);
  78 void ltt_session_destroy(struct ltt_session *session);
  79
  80 struct ltt_channel *ltt_channel_create(struct ltt_session *session,
  81                                        int overwrite, void *buf_addr,
  82                                        size_t subbuf_size, size_t num_subbuf,
  83                                        unsigned int switch_timer_interval,
  84                                        unsigned int read_timer_interval);
  85 void _ltt_channel_destroy(struct ltt_channel *chan);
  86
  87 struct ltt_event *ltt_event_create(struct ltt_channel *chan,
  88                                    char *name,
  89                                    enum instrum_type itype,
  90                                    void *probe, void *filter);
  91 int _ltt_event_destroy(struct ltt_event *event);
  92
  93 void ltt_transport_register(struct ltt_transport *transport);
  94 void ltt_transport_unregister(struct ltt_transport *transport);
  95
  96 int ltt_debugfs_abi_init(void);
  97 void ltt_debugfs_abi_exit(void);
  98
  99 int ltt_probe_register(const char *name, void *cb);
 100 void ltt_probe_unregister(const char *name);
 101 void *ltt_probe_get(const char *name);
 102 void ltt_probe_put(void *cb);
 103 int ltt_probes_init(void);
 104 void ltt_probes_exit(void);
 105
 106 #endif /* _LTT_EVENTS_H */