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

   1 /*
   2  * SPDX-License-Identifier: LGPL-2.1-or-later
   3  *
   4  * Copyright (C) 2013  Mentor Graphics
   5  */
   6
   7 /*
   8  * Do _not_ define _LGPL_SOURCE because we don't want to create a
   9  * circular dependency loop between this malloc wrapper, liburcu and
  10  * libc.
  11  */
  12 #include <lttng/ust-dlfcn.h>
  13 #include <helper.h>
  14 #include <pthread.h>
  15
  16 #define TRACEPOINT_DEFINE
  17 #define TRACEPOINT_CREATE_PROBES
  18 #define TP_IP_PARAM ip
  19 #include "ust_pthread.h"
  20
  21 static __thread int thread_in_trace;
  22
  23 int pthread_mutex_lock(pthread_mutex_t *mutex)
  24 {
  25         static int (*mutex_lock)(pthread_mutex_t *);
  26         int retval;
  27
  28         if (!mutex_lock) {
  29                 mutex_lock = dlsym(RTLD_NEXT, "pthread_mutex_lock");
  30                 if (!mutex_lock) {
  31                         if (thread_in_trace) {
  32                                 abort();
  33                         }
  34                         fprintf(stderr, "unable to initialize pthread wrapper library.\n");
  35                         return EINVAL;
  36                 }
  37         }
  38         if (thread_in_trace) {
  39                 return mutex_lock(mutex);
  40         }
  41
  42         thread_in_trace = 1;
  43         tracepoint(lttng_ust_pthread, pthread_mutex_lock_req, mutex,
  44                 LTTNG_UST_CALLER_IP());
  45         retval = mutex_lock(mutex);
  46         tracepoint(lttng_ust_pthread, pthread_mutex_lock_acq, mutex,
  47                 retval, LTTNG_UST_CALLER_IP());
  48         thread_in_trace = 0;
  49         return retval;
  50 }
  51
  52 int pthread_mutex_trylock(pthread_mutex_t *mutex)
  53 {
  54         static int (*mutex_trylock)(pthread_mutex_t *);
  55         int retval;
  56
  57         if (!mutex_trylock) {
  58                 mutex_trylock = dlsym(RTLD_NEXT, "pthread_mutex_trylock");
  59                 if (!mutex_trylock) {
  60                         if (thread_in_trace) {
  61                                 abort();
  62                         }
  63                         fprintf(stderr, "unable to initialize pthread wrapper library.\n");
  64                         return EINVAL;
  65                 }
  66         }
  67         if (thread_in_trace) {
  68                 return mutex_trylock(mutex);
  69         }
  70
  71         thread_in_trace = 1;
  72         retval = mutex_trylock(mutex);
  73         tracepoint(lttng_ust_pthread, pthread_mutex_trylock, mutex,
  74                 retval, LTTNG_UST_CALLER_IP());
  75         thread_in_trace = 0;
  76         return retval;
  77 }
  78
  79 int pthread_mutex_unlock(pthread_mutex_t *mutex)
  80 {
  81         static int (*mutex_unlock)(pthread_mutex_t *);
  82         int retval;
  83
  84         if (!mutex_unlock) {
  85                 mutex_unlock = dlsym(RTLD_NEXT, "pthread_mutex_unlock");
  86                 if (!mutex_unlock) {
  87                         if (thread_in_trace) {
  88                                 abort();
  89                         }
  90                         fprintf(stderr, "unable to initialize pthread wrapper library.\n");
  91                         return EINVAL;
  92                 }
  93         }
  94         if (thread_in_trace) {
  95                 return mutex_unlock(mutex);
  96         }
  97
  98         thread_in_trace = 1;
  99         retval = mutex_unlock(mutex);
 100         tracepoint(lttng_ust_pthread, pthread_mutex_unlock, mutex,
 101                 retval, LTTNG_UST_CALLER_IP());
 102         thread_in_trace = 0;
 103         return retval;
 104 }