libust/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 "kernelcompat.h"
  11 //ust// #include <linux/percpu.h>
  12
  13 /* ltt's root dir in debugfs */
  14 #define LTT_ROOT        "ltt"
  15
  16 /*
  17  * All modifications of ltt_traces must be done by ltt-tracer.c, while holding
  18  * the semaphore. Only reading of this information can be done elsewhere, with
  19  * the RCU mechanism : the preemption must be disabled while reading the
  20  * list.
  21  */
  22 struct ltt_traces {
  23         struct list_head setup_head;    /* Pre-allocated traces list */
  24         struct list_head head;          /* Allocated Traces list */
  25         unsigned int num_active_traces; /* Number of active traces */
  26 } ____cacheline_aligned;
  27
  28 extern struct ltt_traces ltt_traces;
  29
  30 /*
  31  * get dentry of ltt's root dir
  32  */
  33 struct dentry *get_ltt_root(void);
  34
  35 /* Keep track of trap nesting inside LTT */
  36 //ust// DECLARE_PER_CPU(unsigned int, ltt_nesting);
  37 extern unsigned int ltt_nesting;
  38
  39 typedef int (*ltt_run_filter_functor)(void *trace, uint16_t eID);
  40 //typedef int (*ltt_run_filter_functor)(void *, __u16);
  41
  42 extern ltt_run_filter_functor ltt_run_filter;
  43
  44 extern void ltt_filter_register(ltt_run_filter_functor func);
  45 extern void ltt_filter_unregister(void);
  46
  47 #if defined(CONFIG_LTT) && defined(CONFIG_LTT_ALIGNMENT)
  48
  49 /*
  50  * Calculate the offset needed to align the type.
  51  * size_of_type must be non-zero.
  52  */
  53 static inline unsigned int ltt_align(size_t align_drift, size_t size_of_type)
  54 {
  55         size_t alignment = min(sizeof(void *), size_of_type);
  56         return (alignment - align_drift) & (alignment - 1);
  57 }
  58 /* Default arch alignment */
  59 #define LTT_ALIGN
  60
  61 static inline int ltt_get_alignment(void)
  62 {
  63         return sizeof(void *);
  64 }
  65
  66 #else
  67
  68 static inline unsigned int ltt_align(size_t align_drift,
  69                  size_t size_of_type)
  70 {
  71         return 0;
  72 }
  73
  74 #define LTT_ALIGN __attribute__((packed))
  75
  76 static inline int ltt_get_alignment(void)
  77 {
  78         return 0;
  79 }
  80 #endif /* defined(CONFIG_LTT) && defined(CONFIG_LTT_ALIGNMENT) */
  81
  82 #endif /* LTT_CORE_H */