pthread.cc

   1 #include "common.h"
   2 #include "threads-model.h"
   3 #include "action.h"
   4 #include "mypthread.h"
   5
   6 #include "snapshot-interface.h"
   7 #include "datarace.h"
   8
   9 #include "mutex.h"
  10 #include <condition_variable>
  11 #include <assert.h>
  12
  13 /* global "model" object */
  14 #include "model.h"
  15 #include "execution.h"
  16
  17 int pthread_create(pthread_t *t, const pthread_attr_t * attr,
  18                                                                          pthread_start_t start_routine, void * arg) {
  19         if (!model) {
  20                 snapshot_system_init(10000, 1024, 1024, 40000);
  21                 model = new ModelChecker();
  22                 model->startChecker();
  23         }
  24
  25         struct pthread_params params = { start_routine, arg };
  26
  27         ModelAction *act = new ModelAction(PTHREAD_CREATE, std::memory_order_seq_cst, t, (uint64_t)&params);
  28
  29         /* seq_cst is just a 'don't care' parameter */
  30         model->switch_to_master(act);
  31
  32         return 0;
  33 }
  34
  35 int pthread_join(pthread_t t, void **value_ptr) {
  36 //      Thread *th = model->get_pthread(t);
  37         ModelExecution *execution = model->get_execution();
  38         Thread *th = execution->get_pthread(t);
  39
  40         model->switch_to_master(new ModelAction(PTHREAD_JOIN, std::memory_order_seq_cst, th, id_to_int(th->get_id())));
  41
  42         if ( value_ptr ) {
  43                 // store return value
  44                 void *rtval = th->get_pthread_return();
  45                 *value_ptr = rtval;
  46         }
  47         return 0;
  48 }
  49
  50 int pthread_detach(pthread_t t) {
  51         //Doesn't do anything
  52         //Return success
  53         return 0;
  54 }
  55
  56 void pthread_exit(void *value_ptr) {
  57         Thread * th = thread_current();
  58         th->set_pthread_return(value_ptr);
  59         model->switch_to_master(new ModelAction(THREADONLY_FINISH, std::memory_order_seq_cst, th));
  60         //Need to exit so we don't return to the program
  61         real_pthread_exit(NULL);
  62 }
  63
  64 int pthread_mutex_init(pthread_mutex_t *p_mutex, const pthread_mutexattr_t *) {
  65         cdsc::snapmutex *m = new cdsc::snapmutex();
  66
  67         if (!model) {
  68                 snapshot_system_init(10000, 1024, 1024, 40000);
  69                 model = new ModelChecker();
  70                 model->startChecker();
  71         }
  72
  73         ModelExecution *execution = model->get_execution();
  74         execution->getMutexMap()->put(p_mutex, m);
  75
  76         return 0;
  77 }
  78
  79 int pthread_mutex_lock(pthread_mutex_t *p_mutex) {
  80         if (!model) {
  81                 snapshot_system_init(10000, 1024, 1024, 40000);
  82                 model = new ModelChecker();
  83                 model->startChecker();
  84         }
  85
  86
  87         ModelExecution *execution = model->get_execution();
  88
  89         /* to protect the case where PTHREAD_MUTEX_INITIALIZER is used
  90            instead of pthread_mutex_init, or where *p_mutex is not stored
  91            in the execution->mutex_map for some reason. */
  92         if (!execution->getMutexMap()->contains(p_mutex)) {
  93                 pthread_mutex_init(p_mutex, NULL);
  94         }
  95
  96         cdsc::snapmutex *m = execution->getMutexMap()->get(p_mutex);
  97
  98         if (m != NULL) {
  99                 m->lock();
 100         } else {
 101                 printf("ah\n");
 102         }
 103
 104         return 0;
 105 }
 106
 107 int pthread_mutex_trylock(pthread_mutex_t *p_mutex) {
 108         if (!model) {
 109                 snapshot_system_init(10000, 1024, 1024, 40000);
 110                 model = new ModelChecker();
 111                 model->startChecker();
 112         }
 113
 114         ModelExecution *execution = model->get_execution();
 115         cdsc::snapmutex *m = execution->getMutexMap()->get(p_mutex);
 116         return m->try_lock();
 117 }
 118 int pthread_mutex_unlock(pthread_mutex_t *p_mutex) {
 119         ModelExecution *execution = model->get_execution();
 120         cdsc::snapmutex *m = execution->getMutexMap()->get(p_mutex);
 121
 122         if (m != NULL) {
 123                 m->unlock();
 124         } else {
 125                 printf("try to unlock an untracked pthread_mutex\n");
 126         }
 127
 128         return 0;
 129 }
 130
 131 int pthread_mutex_timedlock (pthread_mutex_t *__restrict p_mutex,
 132                                                                                                                  const struct timespec *__restrict abstime) {
 133 // timedlock just gives the option of giving up the lock, so return and let the scheduler decide which thread goes next
 134
 135 /*
 136         ModelExecution *execution = model->get_execution();
 137         if (!execution->mutex_map.contains(p_mutex)) {
 138                 pthread_mutex_init(p_mutex, NULL);
 139         }
 140         cdsc::snapmutex *m = execution->mutex_map.get(p_mutex);
 141
 142         if (m != NULL) {
 143                 m->lock();
 144         } else {
 145                 printf("something is wrong with pthread_mutex_timedlock\n");
 146         }
 147
 148         printf("pthread_mutex_timedlock is called. It is currently implemented as a normal lock operation without no timeout\n");
 149  */
 150         return 0;
 151 }
 152
 153 pthread_t pthread_self() {
 154         Thread* th = model->get_current_thread();
 155         return (pthread_t)th->get_id();
 156 }
 157
 158 int pthread_key_delete(pthread_key_t) {
 159         model_print("key_delete is called\n");
 160         return 0;
 161 }
 162
 163 int pthread_cond_init(pthread_cond_t *p_cond, const pthread_condattr_t *attr) {
 164         cdsc::snapcondition_variable *v = new cdsc::snapcondition_variable();
 165
 166         ModelExecution *execution = model->get_execution();
 167         execution->getCondMap()->put(p_cond, v);
 168         return 0;
 169 }
 170
 171 int pthread_cond_wait(pthread_cond_t *p_cond, pthread_mutex_t *p_mutex) {
 172         ModelExecution *execution = model->get_execution();
 173         if ( !execution->getCondMap()->contains(p_cond) )
 174                 pthread_cond_init(p_cond, NULL);
 175
 176         cdsc::snapcondition_variable *v = execution->getCondMap()->get(p_cond);
 177         cdsc::snapmutex *m = execution->getMutexMap()->get(p_mutex);
 178
 179         v->wait(*m);
 180         return 0;
 181 }
 182
 183 int pthread_cond_timedwait(pthread_cond_t *p_cond,
 184                                                                                                          pthread_mutex_t *p_mutex, const struct timespec *abstime) {
 185 // implement cond_timedwait as a noop and let the scheduler decide which thread goes next
 186         ModelExecution *execution = model->get_execution();
 187
 188         if ( !execution->getCondMap()->contains(p_cond) )
 189                 pthread_cond_init(p_cond, NULL);
 190         if ( !execution->getMutexMap()->contains(p_mutex) )
 191                 pthread_mutex_init(p_mutex, NULL);
 192
 193         cdsc::snapcondition_variable *v = execution->getCondMap()->get(p_cond);
 194 //      cdsc::snapmutex *m = execution->getMutexMap()->get(p_mutex);
 195
 196         model->switch_to_master(new ModelAction(NOOP, std::memory_order_seq_cst, v));
 197 //      v->wait(*m);
 198 //      printf("timed_wait called\n");
 199         return 0;
 200 }
 201
 202 int pthread_cond_signal(pthread_cond_t *p_cond) {
 203         // notify only one blocked thread
 204         ModelExecution *execution = model->get_execution();
 205         if ( !execution->getCondMap()->contains(p_cond) )
 206                 pthread_cond_init(p_cond, NULL);
 207
 208         cdsc::snapcondition_variable *v = execution->getCondMap()->get(p_cond);
 209
 210         v->notify_one();
 211         return 0;
 212 }
 213
 214 int pthread_cond_broadcast(pthread_cond_t *p_cond) {
 215         // notify all blocked threads
 216         ModelExecution *execution = model->get_execution();
 217         if ( !execution->getCondMap()->contains(p_cond) )
 218                 pthread_cond_init(p_cond, NULL);
 219
 220         cdsc::snapcondition_variable *v = execution->getCondMap()->get(p_cond);
 221
 222         v->notify_all();
 223         return 0;
 224 }
 225
 226 int pthread_cond_destroy(pthread_cond_t *p_cond) {
 227         ModelExecution *execution = model->get_execution();
 228
 229         if (execution->getCondMap()->contains(p_cond)) {
 230                 cdsc::snapcondition_variable *v = execution->getCondMap()->get(p_cond);
 231                 delete v;
 232                 execution->getCondMap()->remove(p_cond);
 233         }
 234         return 0;
 235 }