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  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
  19  */
  20
  21 #ifndef LTT_CORE_H
  22 #define LTT_CORE_H
  23
  24 #include <ust/kernelcompat.h>
  25 //ust// #include <linux/percpu.h>
  26
  27 /* ltt's root dir in debugfs */
  28 #define LTT_ROOT        "ltt"
  29
  30 /*
  31  * All modifications of ltt_traces must be done by ltt-tracer.c, while holding
  32  * the semaphore. Only reading of this information can be done elsewhere, with
  33  * the RCU mechanism : the preemption must be disabled while reading the
  34  * list.
  35  */
  36 struct ltt_traces {
  37         struct list_head setup_head;    /* Pre-allocated traces list */
  38         struct list_head head;          /* Allocated Traces list */
  39         unsigned int num_active_traces; /* Number of active traces */
  40 } ____cacheline_aligned;
  41
  42 extern struct ltt_traces ltt_traces;
  43
  44 /*
  45  * get dentry of ltt's root dir
  46  */
  47 struct dentry *get_ltt_root(void);
  48
  49 /* Keep track of trap nesting inside LTT */
  50 //ust// DECLARE_PER_CPU(unsigned int, ltt_nesting);
  51 extern unsigned int ltt_nesting;
  52
  53 typedef int (*ltt_run_filter_functor)(void *trace, uint16_t eID);
  54 //typedef int (*ltt_run_filter_functor)(void *, __u16);
  55
  56 extern ltt_run_filter_functor ltt_run_filter;
  57
  58 extern void ltt_filter_register(ltt_run_filter_functor func);
  59 extern void ltt_filter_unregister(void);
  60
  61 #if defined(CONFIG_LTT) && defined(CONFIG_LTT_ALIGNMENT)
  62
  63 /*
  64  * Calculate the offset needed to align the type.
  65  * size_of_type must be non-zero.
  66  */
  67 static inline unsigned int ltt_align(size_t align_drift, size_t size_of_type)
  68 {
  69         size_t alignment = min(sizeof(void *), size_of_type);
  70         return (alignment - align_drift) & (alignment - 1);
  71 }
  72 /* Default arch alignment */
  73 #define LTT_ALIGN
  74
  75 static inline int ltt_get_alignment(void)
  76 {
  77         return sizeof(void *);
  78 }
  79
  80 #else
  81
  82 static inline unsigned int ltt_align(size_t align_drift,
  83                  size_t size_of_type)
  84 {
  85         return 0;
  86 }
  87
  88 #define LTT_ALIGN __attribute__((packed))
  89
  90 static inline int ltt_get_alignment(void)
  91 {
  92         return 0;
  93 }
  94 #endif /* defined(CONFIG_LTT) && defined(CONFIG_LTT_ALIGNMENT) */
  95
  96 #endif /* LTT_CORE_H */