libust/tracercore.c

   1 /*
   2  * LTT core in-kernel infrastructure.
   3  *
   4  * Copyright 2006 - Mathieu Desnoyers mathieu.desnoyers@polymtl.ca
   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 #include "tracercore.h"
  22
  23 /* Traces structures */
  24 struct ltt_traces ltt_traces = {
  25         .setup_head = LIST_HEAD_INIT(ltt_traces.setup_head),
  26         .head = LIST_HEAD_INIT(ltt_traces.head),
  27 };
  28
  29 /* Traces list writer locking */
  30 static DEFINE_MUTEX(ltt_traces_mutex);
  31
  32 void ltt_lock_traces(void)
  33 {
  34         mutex_lock(&ltt_traces_mutex);
  35 }
  36
  37 void ltt_unlock_traces(void)
  38 {
  39         mutex_unlock(&ltt_traces_mutex);
  40 }
  41
  42 //ust// DEFINE_PER_CPU(unsigned int, ltt_nesting);
  43 //ust// EXPORT_PER_CPU_SYMBOL(ltt_nesting);
  44 __thread int ltt_nesting;
  45
  46 int ltt_run_filter_default(void *trace, uint16_t eID)
  47 {
  48         return 1;
  49 }
  50
  51 /* This function pointer is protected by a trace activation check */
  52 ltt_run_filter_functor ltt_run_filter = ltt_run_filter_default;
  53
  54 void ltt_filter_register(ltt_run_filter_functor func)
  55 {
  56         ltt_run_filter = func;
  57 }
  58
  59 void ltt_filter_unregister(void)
  60 {
  61         ltt_run_filter = ltt_run_filter_default;
  62 }