liblttng-ust-libc-wrapper/lttng-ust-pthread.c

   1 /*
   2  * Copyright (C) 2013  Mentor Graphics
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
  17  */
  18
  19 /*
  20  * Do _not_ define _LGPL_SOURCE because we don't want to create a
  21  * circular dependency loop between this malloc wrapper, liburcu and
  22  * libc.
  23  */
  24 #include <lttng/ust-dlfcn.h>
  25 #include <helper.h>
  26 #include <pthread.h>
  27
  28 #define TRACEPOINT_DEFINE
  29 #define TRACEPOINT_CREATE_PROBES
  30 #define TP_IP_PARAM ip
  31 #include "ust_pthread.h"
  32
  33 static __thread int thread_in_trace;
  34
  35 int pthread_mutex_lock(pthread_mutex_t *mutex)
  36 {
  37         static int (*mutex_lock)(pthread_mutex_t *);
  38         int retval;
  39
  40         if (!mutex_lock) {
  41                 mutex_lock = dlsym(RTLD_NEXT, "pthread_mutex_lock");
  42                 if (!mutex_lock) {
  43                         if (thread_in_trace) {
  44                                 abort();
  45                         }
  46                         fprintf(stderr, "unable to initialize pthread wrapper library.\n");
  47                         return EINVAL;
  48                 }
  49         }
  50         if (thread_in_trace) {
  51                 return mutex_lock(mutex);
  52         }
  53
  54         thread_in_trace = 1;
  55         tracepoint(lttng_ust_pthread, pthread_mutex_lock_req, mutex,
  56                 LTTNG_UST_CALLER_IP());
  57         retval = mutex_lock(mutex);
  58         tracepoint(lttng_ust_pthread, pthread_mutex_lock_acq, mutex,
  59                 retval, LTTNG_UST_CALLER_IP());
  60         thread_in_trace = 0;
  61         return retval;
  62 }
  63
  64 int pthread_mutex_trylock(pthread_mutex_t *mutex)
  65 {
  66         static int (*mutex_trylock)(pthread_mutex_t *);
  67         int retval;
  68
  69         if (!mutex_trylock) {
  70                 mutex_trylock = dlsym(RTLD_NEXT, "pthread_mutex_trylock");
  71                 if (!mutex_trylock) {
  72                         if (thread_in_trace) {
  73                                 abort();
  74                         }
  75                         fprintf(stderr, "unable to initialize pthread wrapper library.\n");
  76                         return EINVAL;
  77                 }
  78         }
  79         if (thread_in_trace) {
  80                 return mutex_trylock(mutex);
  81         }
  82
  83         thread_in_trace = 1;
  84         retval = mutex_trylock(mutex);
  85         tracepoint(lttng_ust_pthread, pthread_mutex_trylock, mutex,
  86                 retval, LTTNG_UST_CALLER_IP());
  87         thread_in_trace = 0;
  88         return retval;
  89 }
  90
  91 int pthread_mutex_unlock(pthread_mutex_t *mutex)
  92 {
  93         static int (*mutex_unlock)(pthread_mutex_t *);
  94         int retval;
  95
  96         if (!mutex_unlock) {
  97                 mutex_unlock = dlsym(RTLD_NEXT, "pthread_mutex_unlock");
  98                 if (!mutex_unlock) {
  99                         if (thread_in_trace) {
 100                                 abort();
 101                         }
 102                         fprintf(stderr, "unable to initialize pthread wrapper library.\n");
 103                         return EINVAL;
 104                 }
 105         }
 106         if (thread_in_trace) {
 107                 return mutex_unlock(mutex);
 108         }
 109
 110         thread_in_trace = 1;
 111         retval = mutex_unlock(mutex);
 112         tracepoint(lttng_ust_pthread, pthread_mutex_unlock, mutex,
 113                 retval, LTTNG_UST_CALLER_IP());
 114         thread_in_trace = 0;
 115         return retval;
 116 }