libtracing/tracercore.h

   1 /*
   2  * Copyright (C) 2005,2006 Mathieu Desnoyers (mathieu.desnoyers@polymtl.ca)
   3  *
   4  * This contains the core definitions for the Linux Trace Toolkit.
   5  */
   6
   7 #ifndef LTT_CORE_H
   8 #define LTT_CORE_H
   9
  10 #include "list.h"
  11 #include "kernelcompat.h"
  12 //ust// #include <linux/percpu.h>
  13
  14 /* ltt's root dir in debugfs */
  15 #define LTT_ROOT        "ltt"
  16
  17 /*
  18  * All modifications of ltt_traces must be done by ltt-tracer.c, while holding
  19  * the semaphore. Only reading of this information can be done elsewhere, with
  20  * the RCU mechanism : the preemption must be disabled while reading the
  21  * list.
  22  */
  23 struct ltt_traces {
  24         struct list_head setup_head;    /* Pre-allocated traces list */
  25         struct list_head head;          /* Allocated Traces list */
  26         unsigned int num_active_traces; /* Number of active traces */
  27 } ____cacheline_aligned;
  28
  29 extern struct ltt_traces ltt_traces;
  30
  31 /*
  32  * get dentry of ltt's root dir
  33  */
  34 struct dentry *get_ltt_root(void);
  35
  36 /* Keep track of trap nesting inside LTT */
  37 //ust// DECLARE_PER_CPU(unsigned int, ltt_nesting);
  38
  39 typedef int (*ltt_run_filter_functor)(void *trace, uint16_t eID);
  40
  41 extern ltt_run_filter_functor ltt_run_filter;
  42
  43 extern void ltt_filter_register(ltt_run_filter_functor func);
  44 extern void ltt_filter_unregister(void);
  45
  46 #if defined(CONFIG_LTT) && defined(CONFIG_LTT_ALIGNMENT)
  47
  48 /*
  49  * Calculate the offset needed to align the type.
  50  * size_of_type must be non-zero.
  51  */
  52 static inline unsigned int ltt_align(size_t align_drift, size_t size_of_type)
  53 {
  54         size_t alignment = min(sizeof(void *), size_of_type);
  55         return (alignment - align_drift) & (alignment - 1);
  56 }
  57 /* Default arch alignment */
  58 #define LTT_ALIGN
  59
  60 static inline int ltt_get_alignment(void)
  61 {
  62         return sizeof(void *);
  63 }
  64
  65 #else
  66
  67 static inline unsigned int ltt_align(size_t align_drift,
  68                  size_t size_of_type)
  69 {
  70         return 0;
  71 }
  72
  73 #define LTT_ALIGN __attribute__((packed))
  74
  75 static inline int ltt_get_alignment(void)
  76 {
  77         return 0;
  78 }
  79 #endif /* defined(CONFIG_LTT) && defined(CONFIG_LTT_ALIGNMENT) */
  80
  81 #endif /* LTT_CORE_H */