src/lib/lttng-ust-pthread-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
  13 /* Has to be included first to override dlfcn.h */
  14 #include <common/compat/dlfcn.h>
  15
  16 #include "common/macros.h"
  17 #include <pthread.h>
  18
  19 #define LTTNG_UST_TRACEPOINT_HIDDEN_DEFINITION
  20 #define LTTNG_UST_TRACEPOINT_PROVIDER_HIDDEN_DEFINITION
  21
  22 #define LTTNG_UST_TRACEPOINT_DEFINE
  23 #define LTTNG_UST_TRACEPOINT_CREATE_PROBES
  24 #define LTTNG_UST_TP_IP_PARAM ip
  25 #include "ust_pthread.h"
  26
  27 static __thread int thread_in_trace;
  28
  29 int pthread_mutex_lock(pthread_mutex_t *mutex)
  30 {
  31         static int (*mutex_lock)(pthread_mutex_t *);
  32         int retval;
  33
  34         if (!mutex_lock) {
  35                 mutex_lock = dlsym(RTLD_NEXT, "pthread_mutex_lock");
  36                 if (!mutex_lock) {
  37                         if (thread_in_trace) {
  38                                 abort();
  39                         }
  40                         fprintf(stderr, "unable to initialize pthread wrapper library.\n");
  41                         return EINVAL;
  42                 }
  43         }
  44         if (thread_in_trace) {
  45                 return mutex_lock(mutex);
  46         }
  47
  48         thread_in_trace = 1;
  49         lttng_ust_tracepoint(lttng_ust_pthread, pthread_mutex_lock_req, mutex,
  50                 LTTNG_UST_CALLER_IP());
  51         retval = mutex_lock(mutex);
  52         lttng_ust_tracepoint(lttng_ust_pthread, pthread_mutex_lock_acq, mutex,
  53                 retval, LTTNG_UST_CALLER_IP());
  54         thread_in_trace = 0;
  55         return retval;
  56 }
  57
  58 int pthread_mutex_trylock(pthread_mutex_t *mutex)
  59 {
  60         static int (*mutex_trylock)(pthread_mutex_t *);
  61         int retval;
  62
  63         if (!mutex_trylock) {
  64                 mutex_trylock = dlsym(RTLD_NEXT, "pthread_mutex_trylock");
  65                 if (!mutex_trylock) {
  66                         if (thread_in_trace) {
  67                                 abort();
  68                         }
  69                         fprintf(stderr, "unable to initialize pthread wrapper library.\n");
  70                         return EINVAL;
  71                 }
  72         }
  73         if (thread_in_trace) {
  74                 return mutex_trylock(mutex);
  75         }
  76
  77         thread_in_trace = 1;
  78         retval = mutex_trylock(mutex);
  79         lttng_ust_tracepoint(lttng_ust_pthread, pthread_mutex_trylock, mutex,
  80                 retval, LTTNG_UST_CALLER_IP());
  81         thread_in_trace = 0;
  82         return retval;
  83 }
  84
  85 int pthread_mutex_unlock(pthread_mutex_t *mutex)
  86 {
  87         static int (*mutex_unlock)(pthread_mutex_t *);
  88         int retval;
  89
  90         if (!mutex_unlock) {
  91                 mutex_unlock = dlsym(RTLD_NEXT, "pthread_mutex_unlock");
  92                 if (!mutex_unlock) {
  93                         if (thread_in_trace) {
  94                                 abort();
  95                         }
  96                         fprintf(stderr, "unable to initialize pthread wrapper library.\n");
  97                         return EINVAL;
  98                 }
  99         }
 100         if (thread_in_trace) {
 101                 return mutex_unlock(mutex);
 102         }
 103
 104         thread_in_trace = 1;
 105         retval = mutex_unlock(mutex);
 106         lttng_ust_tracepoint(lttng_ust_pthread, pthread_mutex_unlock, mutex,
 107                 retval, LTTNG_UST_CALLER_IP());
 108         thread_in_trace = 0;
 109         return retval;
 110 }