src/simix/smx_network.c

   1 /* Copyright (c) 2009, 2010. The SimGrid Team.
   2  * All rights reserved.                                                     */
   3
   4 /* This program is free software; you can redistribute it and/or modify it
   5  * under the terms of the license (GNU LGPL) which comes with this package. */
   6
   7 #include "private.h"
   8 #include "xbt/log.h"
   9 #include "mc/mc.h"
  10 #include "xbt/dict.h"
  11
  12 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(simix_network, simix,
  13                                 "Logging specific to SIMIX (network)");
  14
  15 static xbt_dict_t rdv_points = NULL;
  16
  17 static XBT_INLINE void SIMIX_comm_start(smx_action_t action);
  18 static void SIMIX_comm_finish(smx_action_t action);
  19 static void SIMIX_waitany_req_remove_from_actions(smx_req_t req);
  20 static void SIMIX_comm_copy_data(smx_action_t comm);
  21 static smx_action_t SIMIX_comm_new(e_smx_comm_type_t type);
  22 static XBT_INLINE void SIMIX_comm_wait_for_completion(smx_action_t comm,
  23                                                       double timeout);
  24 static XBT_INLINE void SIMIX_rdv_push(smx_rdv_t rdv, smx_action_t comm);
  25 static XBT_INLINE void SIMIX_rdv_remove(smx_rdv_t rdv, smx_action_t comm);
  26 static smx_action_t SIMIX_rdv_get_request(smx_rdv_t rdv, e_smx_comm_type_t type,
  27                                                                                   int (*match_fun)(void *, void *), void *);
  28 static void SIMIX_rdv_free(void *data);
  29
  30 void SIMIX_network_init(void)
  31 {
  32   rdv_points = xbt_dict_new();
  33 }
  34
  35 void SIMIX_network_exit(void)
  36 {
  37   xbt_dict_free(&rdv_points);
  38 }
  39
  40 /******************************************************************************/
  41 /*                           Rendez-Vous Points                               */
  42 /******************************************************************************/
  43
  44 smx_rdv_t SIMIX_rdv_create(const char *name)
  45 {
  46   /* two processes may have pushed the same rdv_create request at the same time */
  47   smx_rdv_t rdv = name ? xbt_dict_get_or_null(rdv_points, name) : NULL;
  48
  49   if (!rdv) {
  50     rdv = xbt_new0(s_smx_rvpoint_t, 1);
  51     rdv->name = name ? xbt_strdup(name) : NULL;
  52     rdv->comm_fifo = xbt_fifo_new();
  53
  54     if (name)
  55       xbt_dict_set(rdv_points, name, rdv, SIMIX_rdv_free);
  56   }
  57   return rdv;
  58 }
  59
  60 void SIMIX_rdv_destroy(smx_rdv_t rdv)
  61 {
  62   if (rdv->name)
  63     xbt_dict_remove(rdv_points, rdv->name);
  64 }
  65
  66 void SIMIX_rdv_free(void *data)
  67 {
  68   smx_rdv_t rdv = (smx_rdv_t) data;
  69   if (rdv->name)
  70     xbt_free(rdv->name);
  71   xbt_fifo_free(rdv->comm_fifo);
  72   xbt_free(rdv);
  73 }
  74
  75 smx_rdv_t SIMIX_rdv_get_by_name(const char *name)
  76 {
  77   return xbt_dict_get_or_null(rdv_points, name);
  78 }
  79
  80 int SIMIX_rdv_comm_count_by_host(smx_rdv_t rdv, smx_host_t host)
  81 {
  82   smx_action_t comm = NULL;
  83   xbt_fifo_item_t item = NULL;
  84   int count = 0;
  85
  86   xbt_fifo_foreach(rdv->comm_fifo, item, comm, smx_action_t) {
  87     if (comm->comm.src_proc->smx_host == host)
  88       count++;
  89   }
  90
  91   return count;
  92 }
  93
  94 smx_action_t SIMIX_rdv_get_head(smx_rdv_t rdv)
  95 {
  96   return xbt_fifo_get_item_content(xbt_fifo_get_first_item(rdv->comm_fifo));
  97 }
  98
  99 /**
 100  *  \brief Push a communication request into a rendez-vous point
 101  *  \param rdv The rendez-vous point
 102  *  \param comm The communication request
 103  */
 104 static XBT_INLINE void SIMIX_rdv_push(smx_rdv_t rdv, smx_action_t comm)
 105 {
 106   xbt_fifo_push(rdv->comm_fifo, comm);
 107   comm->comm.rdv = rdv;
 108 }
 109
 110 /**
 111  *  \brief Remove a communication request from a rendez-vous point
 112  *  \param rdv The rendez-vous point
 113  *  \param comm The communication request
 114  */
 115 static XBT_INLINE void SIMIX_rdv_remove(smx_rdv_t rdv, smx_action_t comm)
 116 {
 117   xbt_fifo_remove(rdv->comm_fifo, comm);
 118   comm->comm.rdv = NULL;
 119 }
 120
 121 /**
 122  *  \brief Checks if there is a communication action queued in a rendez-vous matching our needs
 123  *  \param type The type of communication we are looking for (comm_send, comm_recv)
 124  *  \return The communication action if found, NULL otherwise
 125  */
 126 smx_action_t SIMIX_rdv_get_request(smx_rdv_t rdv, e_smx_comm_type_t type,
 127                                    int (*match_fun)(void *, void *), void *data)
 128 {
 129   smx_action_t action;
 130   xbt_fifo_item_t item;
 131   void* req_data = NULL;
 132
 133   xbt_fifo_foreach(rdv->comm_fifo, item, action, smx_action_t){
 134     if (action->comm.type == SIMIX_COMM_SEND) {
 135       req_data = action->comm.src_data;
 136     } else if (action->comm.type == SIMIX_COMM_RECEIVE) {
 137       req_data = action->comm.dst_data;
 138     }
 139     if (action->comm.type == type && (!match_fun || match_fun(data, req_data))) {
 140       DEBUG1("Found a matching communication action %p", action);
 141       xbt_fifo_remove_item(rdv->comm_fifo, item);
 142       xbt_fifo_free_item(item);
 143       action->comm.refcount++;
 144       action->comm.rdv = NULL;
 145       return action;
 146     }
 147     DEBUG3("Sorry, communication action %p does not match our needs:"
 148            " its type is %d but we are looking for a comm of type %d",
 149            action, action->comm.type, type);
 150   }
 151   DEBUG0("No matching communication action found");
 152   return NULL;
 153 }
 154
 155 /******************************************************************************/
 156 /*                            Comunication Actions                            */
 157 /******************************************************************************/
 158
 159 /**
 160  *  \brief Creates a new comunicate action
 161  *  \param type The type of request (comm_send, comm_recv)
 162  *  \return The new comunicate action
 163  */
 164 smx_action_t SIMIX_comm_new(e_smx_comm_type_t type)
 165 {
 166   smx_action_t act;
 167
 168   /* alloc structures */
 169   act = xbt_new0(s_smx_action_t, 1);
 170   act->type = SIMIX_ACTION_COMMUNICATE;
 171   act->state = SIMIX_WAITING;
 172   act->request_list = xbt_fifo_new();
 173
 174   /* set communication */
 175   act->comm.type = type;
 176   act->comm.refcount = 1;
 177
 178 #ifdef HAVE_LATENCY_BOUND_TRACKING
 179   //initialize with unknown value
 180   act->latency_limited = -1;
 181 #endif
 182
 183 #ifdef HAVE_TRACING
 184   act->category = NULL;
 185 #endif
 186
 187   DEBUG1("Create communicate action %p", act);
 188
 189   return act;
 190 }
 191
 192 /**
 193  *  \brief Destroy a communicate action
 194  *  \param action The communicate action to be destroyed
 195  */
 196 void SIMIX_comm_destroy(smx_action_t action)
 197 {
 198   DEBUG2("Destroy action %p (refcount:%d)", action, action->comm.refcount);
 199
 200   if (action->comm.refcount <= 0)
 201     xbt_die(bprintf("the refcount of comm %p is already 0 before decreasing it. That's a bug!",action));
 202
 203   action->comm.refcount--;
 204   if (action->comm.refcount > 0)
 205     return;
 206   DEBUG2("Really free communication %p; refcount is now %d", action,
 207         action->comm.refcount);
 208
 209 #ifdef HAVE_LATENCY_BOUND_TRACKING
 210     action->latency_limited = SIMIX_comm_is_latency_bounded( action ) ;
 211 #endif
 212
 213 #ifdef HAVE_TRACING
 214   TRACE_smx_action_destroy(action);
 215 #endif
 216
 217   if (action->name)
 218     xbt_free(action->name);
 219
 220   xbt_fifo_free(action->request_list);
 221
 222   SIMIX_comm_destroy_internal_actions(action);
 223
 224   xbt_free(action);
 225 }
 226
 227 void SIMIX_comm_destroy_internal_actions(smx_action_t action)
 228 {
 229   if (action->comm.surf_comm){
 230 #ifdef HAVE_LATENCY_BOUND_TRACKING
 231     action->latency_limited = SIMIX_comm_is_latency_bounded(action);
 232 #endif
 233     action->comm.surf_comm->model_type->action_unref(action->comm.surf_comm);
 234     action->comm.surf_comm = NULL;
 235   }
 236
 237   if (action->comm.src_timeout){
 238     action->comm.src_timeout->model_type->action_unref(action->comm.src_timeout);
 239     action->comm.src_timeout = NULL;
 240   }
 241
 242   if (action->comm.dst_timeout){
 243     action->comm.dst_timeout->model_type->action_unref(action->comm.dst_timeout);
 244     action->comm.dst_timeout = NULL;
 245   }
 246 }
 247
 248 smx_action_t SIMIX_comm_isend(smx_process_t src_proc, smx_rdv_t rdv,
 249                               double task_size, double rate,
 250                               void *src_buff, size_t src_buff_size,
 251                               int (*match_fun)(void *, void *), void *data)
 252 {
 253   smx_action_t action;
 254
 255   /* Look for communication request matching our needs.
 256      If it is not found then create it and push it into the rendez-vous point */
 257   action = SIMIX_rdv_get_request(rdv, SIMIX_COMM_RECEIVE, match_fun, data);
 258
 259   if (!action) {
 260     action = SIMIX_comm_new(SIMIX_COMM_SEND);
 261     SIMIX_rdv_push(rdv, action);
 262   } else {
 263     action->state = SIMIX_READY;
 264     action->comm.type = SIMIX_COMM_READY;
 265   }
 266
 267   /* Setup the communication request */
 268   action->comm.src_proc = src_proc;
 269   action->comm.task_size = task_size;
 270   action->comm.rate = rate;
 271   action->comm.src_buff = src_buff;
 272   action->comm.src_buff_size = src_buff_size;
 273   action->comm.src_data = data;
 274
 275   if (MC_IS_ENABLED) {
 276     action->state = SIMIX_RUNNING;
 277     return action;
 278   }
 279
 280   SIMIX_comm_start(action);
 281   return action;
 282 }
 283
 284 smx_action_t SIMIX_comm_irecv(smx_process_t dst_proc, smx_rdv_t rdv,
 285                       void *dst_buff, size_t *dst_buff_size,
 286                       int (*match_fun)(void *, void *), void *data)
 287 {
 288   smx_action_t action;
 289
 290   /* Look for communication request matching our needs.
 291    * If it is not found then create it and push it into the rendez-vous point
 292    */
 293   action = SIMIX_rdv_get_request(rdv, SIMIX_COMM_SEND, match_fun, data);
 294
 295   if (!action) {
 296     action = SIMIX_comm_new(SIMIX_COMM_RECEIVE);
 297     SIMIX_rdv_push(rdv, action);
 298   } else {
 299     action->state = SIMIX_READY;
 300     action->comm.type = SIMIX_COMM_READY;
 301   }
 302
 303   /* Setup communication request */
 304   action->comm.dst_proc = dst_proc;
 305   action->comm.dst_buff = dst_buff;
 306   action->comm.dst_buff_size = dst_buff_size;
 307   action->comm.dst_data = data;
 308
 309   if (MC_IS_ENABLED) {
 310     action->state = SIMIX_RUNNING;
 311     return action;
 312   }
 313
 314   SIMIX_comm_start(action);
 315   return action;
 316 }
 317
 318 void SIMIX_pre_comm_wait(smx_req_t req)
 319 {
 320   smx_action_t action = req->comm_wait.comm;
 321   double timeout = req->comm_wait.timeout;
 322   surf_action_t sleep;
 323
 324   /* Associate this request to the action */
 325   xbt_fifo_push(action->request_list, req);
 326   req->issuer->waiting_action = action;
 327
 328   if (MC_IS_ENABLED){
 329     action->state = SIMIX_DONE;
 330     SIMIX_comm_finish(action);
 331     return;
 332   }
 333
 334   /* If the action has already finish perform the error handling, */
 335   /* otherwise set up a waiting timeout on the right side         */
 336   if (action->state != SIMIX_WAITING && action->state != SIMIX_RUNNING) {
 337     SIMIX_comm_finish(action);
 338   } else { /* if (timeout >= 0) { we need a surf sleep action even when there is no timeout, otherwise surf won't tell us when the host fails */
 339     sleep = surf_workstation_model->extension.workstation.sleep(req->issuer->smx_host->host, timeout);
 340     surf_workstation_model->action_data_set(sleep, action);
 341
 342     if (req->issuer == action->comm.src_proc)
 343       action->comm.src_timeout = sleep;
 344     else
 345       action->comm.dst_timeout = sleep;
 346   }
 347 }
 348
 349 void SIMIX_pre_comm_test(smx_req_t req)
 350 {
 351   smx_action_t action = req->comm_test.comm;
 352   req->comm_test.result = (action->state != SIMIX_WAITING && action->state != SIMIX_RUNNING);
 353
 354   if (req->comm_test.result) {
 355     xbt_fifo_push(action->request_list, req);
 356     SIMIX_comm_finish(action);
 357   } else {
 358     SIMIX_request_answer(req);
 359   }
 360 }
 361
 362 void SIMIX_pre_comm_testany(smx_req_t req)
 363 {
 364   unsigned int cursor;
 365   smx_action_t action;
 366   req->comm_testany.result = -1;
 367   xbt_dynar_foreach(req->comm_testany.comms,cursor,action) {
 368     if (action->state != SIMIX_WAITING && action->state != SIMIX_RUNNING) {
 369       req->comm_testany.result = cursor;
 370       xbt_fifo_push(action->request_list, req);
 371       SIMIX_comm_finish(action);
 372       return;
 373     }
 374   }
 375   SIMIX_request_answer(req);
 376 }
 377
 378 void SIMIX_pre_comm_waitany(smx_req_t req)
 379 {
 380   smx_action_t action;
 381   unsigned int cursor = 0;
 382   xbt_dynar_t actions = req->comm_waitany.comms;
 383   xbt_dynar_foreach(actions, cursor, action){
 384     /* Associate this request to the action */
 385     xbt_fifo_push(action->request_list, req);
 386     if (action->state != SIMIX_WAITING && action->state != SIMIX_RUNNING){
 387       SIMIX_comm_finish(action);
 388       break;
 389     }
 390   }
 391 }
 392
 393 void SIMIX_waitany_req_remove_from_actions(smx_req_t req)
 394 {
 395   smx_action_t action;
 396   unsigned int cursor = 0;
 397   xbt_dynar_t actions = req->comm_waitany.comms;
 398
 399   xbt_dynar_foreach(actions, cursor, action){
 400     xbt_fifo_remove(action->request_list, req);
 401   }
 402 }
 403
 404 /**
 405  *  \brief Start the simulation of a communication request
 406  *  \param action The communication action
 407  */
 408 static XBT_INLINE void SIMIX_comm_start(smx_action_t action)
 409 {
 410   /* If both the sender and the receiver are already there, start the communication */
 411   if (action->state == SIMIX_READY) {
 412     smx_host_t sender = action->comm.src_proc->smx_host;
 413     smx_host_t receiver = action->comm.dst_proc->smx_host;
 414
 415     DEBUG3("Starting communication %p from '%s' to '%s'", action,
 416            SIMIX_host_get_name(sender), SIMIX_host_get_name(receiver));
 417
 418     action->comm.surf_comm = surf_workstation_model->extension.workstation.
 419         communicate(sender->host, receiver->host, action->comm.task_size, action->comm.rate);
 420
 421     surf_workstation_model->action_data_set(action->comm.surf_comm, action);
 422
 423     action->state = SIMIX_RUNNING;
 424
 425 #ifdef HAVE_TRACING
 426     TRACE_smx_action_communicate(action, action->comm.src_proc);
 427 #endif
 428
 429     /* If a link is failed, detect it immediately */
 430     if (surf_workstation_model->action_state_get(action->comm.surf_comm) == SURF_ACTION_FAILED) {
 431       DEBUG2("Communication from '%s' to '%s' failed to start because of a link failure",
 432           SIMIX_host_get_name(sender), SIMIX_host_get_name(receiver));
 433       action->state = SIMIX_LINK_FAILURE;
 434       SIMIX_comm_destroy_internal_actions(action);
 435     }
 436
 437     /* If any of the process is suspend, create the action but stop its execution,
 438        it will be restarted when the sender process resume */
 439     if (SIMIX_process_is_suspended(action->comm.src_proc) ||
 440         SIMIX_process_is_suspended(action->comm.dst_proc)) {
 441       /* FIXME: check what should happen with the action state */
 442       surf_workstation_model->suspend(action->comm.surf_comm);
 443     }
 444   }
 445 }
 446
 447 void SIMIX_comm_finish(smx_action_t action)
 448 {
 449   smx_req_t req;
 450
 451   while ((req = xbt_fifo_shift(action->request_list))) {
 452
 453     /* If a waitany request is waiting for this action to finish, then remove
 454        it from the other actions in the waitany list. Afterwards, get the
 455        position of the actual action in the waitany request's actions dynar and
 456        return it as the result of the call */
 457     if (req->call == REQ_COMM_WAITANY) {
 458       SIMIX_waitany_req_remove_from_actions(req);
 459       req->comm_waitany.result = xbt_dynar_search(req->comm_waitany.comms, &action);
 460     }
 461
 462     /* If the action is still in a rendez-vous point then remove from it */
 463     if (action->comm.rdv)
 464       SIMIX_rdv_remove(action->comm.rdv, action);
 465
 466     DEBUG1("SIMIX_comm_finish: action state = %d", action->state);
 467
 468     /* Check out for errors */
 469     switch (action->state) {
 470
 471       case SIMIX_DONE:
 472         DEBUG1("Communication %p complete!", action);
 473         SIMIX_comm_copy_data(action);
 474         break;
 475
 476       case SIMIX_SRC_TIMEOUT:
 477         TRY {
 478           THROW0(timeout_error, 0, "Communication timeouted because of sender");
 479         }
 480         CATCH(req->issuer->running_ctx->exception) {
 481           req->issuer->doexception = 1;
 482         }
 483         break;
 484
 485       case SIMIX_DST_TIMEOUT:
 486         TRY {
 487           THROW0(timeout_error, 0, "Communication timeouted because of receiver");
 488         }
 489         CATCH(req->issuer->running_ctx->exception) {
 490           req->issuer->doexception = 1;
 491         }
 492         break;
 493
 494       case SIMIX_SRC_HOST_FAILURE:
 495         TRY {
 496           if (req->issuer == action->comm.src_proc)
 497             THROW0(host_error, 0, "Host failed");
 498           else
 499             THROW0(network_error, 0, "Remote peer failed");
 500         }
 501         CATCH(req->issuer->running_ctx->exception) {
 502           req->issuer->doexception = 1;
 503         }
 504         break;
 505
 506       case SIMIX_DST_HOST_FAILURE:
 507         TRY {
 508           if (req->issuer == action->comm.dst_proc)
 509             THROW0(host_error, 0, "Host failed");
 510           else
 511             THROW0(network_error, 0, "Remote peer failed");
 512         }
 513         CATCH(req->issuer->running_ctx->exception) {
 514           req->issuer->doexception = 1;
 515         }
 516         break;
 517
 518       case SIMIX_LINK_FAILURE:
 519         TRY {
 520           DEBUG5("Link failure in action %p between '%s' and '%s': posting an exception to the issuer: %s (%p)",
 521               action, action->comm.src_proc->smx_host->name, action->comm.dst_proc->smx_host->name,
 522               req->issuer->name, req->issuer);
 523           THROW0(network_error, 0, "Link failure");
 524         }
 525         CATCH(req->issuer->running_ctx->exception) {
 526           req->issuer->doexception = 1;
 527         }
 528         break;
 529
 530       default:
 531         THROW_IMPOSSIBLE;
 532     }
 533
 534     /* if there is an exception during a waitany or a testany, indicate the position of the failed communication */
 535     if (req->issuer->doexception) {
 536       if (req->call == REQ_COMM_WAITANY) {
 537         req->issuer->running_ctx->exception.value = xbt_dynar_search(req->comm_waitany.comms, &action);
 538       }
 539       else if (req->call == REQ_COMM_TESTANY) {
 540         req->issuer->running_ctx->exception.value = xbt_dynar_search(req->comm_testany.comms, &action);
 541       }
 542     }
 543
 544     req->issuer->waiting_action = NULL;
 545     SIMIX_request_answer(req);
 546   }
 547 }
 548
 549 void SIMIX_post_comm(smx_action_t action)
 550 {
 551   /* Update action state */
 552   if (action->comm.src_timeout &&
 553      surf_workstation_model->action_state_get(action->comm.src_timeout) == SURF_ACTION_DONE)
 554      action->state = SIMIX_SRC_TIMEOUT;
 555   else if (action->comm.dst_timeout &&
 556           surf_workstation_model->action_state_get(action->comm.dst_timeout) == SURF_ACTION_DONE)
 557      action->state = SIMIX_DST_TIMEOUT;
 558   else if (action->comm.src_timeout &&
 559           surf_workstation_model->action_state_get(action->comm.src_timeout) == SURF_ACTION_FAILED)
 560      action->state = SIMIX_SRC_HOST_FAILURE;
 561   else if (action->comm.dst_timeout &&
 562           surf_workstation_model->action_state_get(action->comm.dst_timeout) == SURF_ACTION_FAILED)
 563      action->state = SIMIX_DST_HOST_FAILURE;
 564   else if (action->comm.surf_comm &&
 565           surf_workstation_model->action_state_get(action->comm.surf_comm) == SURF_ACTION_FAILED)
 566      action->state = SIMIX_LINK_FAILURE;
 567   else
 568     action->state = SIMIX_DONE;
 569
 570   DEBUG1("SIMIX_post_comm: action state = %d", action->state);
 571
 572   /* After this point the surf actions associated with the simix communicate
 573      action are no longer needed, thus we delete them. */
 574   SIMIX_comm_destroy_internal_actions(action);
 575
 576   /* If there are requests associated with the action, then answer them */
 577   if (xbt_fifo_size(action->request_list))
 578     SIMIX_comm_finish(action);
 579 }
 580
 581 void SIMIX_comm_cancel(smx_action_t action)
 582 {
 583   /* If the action is a waiting state means that it is still in a rdv */
 584   /* so remove from it and delete it */
 585   if (action->state == SIMIX_WAITING) {
 586     SIMIX_rdv_remove(action->comm.rdv, action);
 587     action->state = SIMIX_FAILED;
 588   } else {
 589     surf_workstation_model->action_cancel(action->comm.surf_comm);
 590   }
 591 }
 592
 593 void SIMIX_comm_suspend(smx_action_t action)
 594 {
 595   /*FIXME: shall we suspend also the timeout actions? */
 596   surf_workstation_model->suspend(action->comm.surf_comm);
 597 }
 598
 599 void SIMIX_comm_resume(smx_action_t action)
 600 {
 601   /*FIXME: check what happen with the timeouts */
 602   surf_workstation_model->resume(action->comm.surf_comm);
 603 }
 604
 605
 606 /************* Action Getters **************/
 607
 608 /**
 609  *  \brief get the amount remaining from the communication
 610  *  \param action The communication
 611  */
 612 double SIMIX_comm_get_remains(smx_action_t action)
 613 {
 614   double remains;
 615
 616   switch (action->state) {
 617
 618     case SIMIX_RUNNING:
 619       remains = surf_workstation_model->get_remains(action->comm.surf_comm);
 620       break;
 621
 622     case SIMIX_WAITING:
 623     case SIMIX_READY:
 624       remains = 0; /*FIXME: check what should be returned */
 625       break;
 626
 627     default:
 628       remains = 0; /*FIXME: is this correct? */
 629       break;
 630   }
 631   return remains;
 632 }
 633
 634 e_smx_state_t SIMIX_comm_get_state(smx_action_t action)
 635 {
 636   return action->state;
 637 }
 638
 639 /**
 640  *  \brief Return the user data associated to the sender of the communication
 641  *  \param action The communication
 642  *  \return the user data
 643  */
 644 void* SIMIX_comm_get_src_data(smx_action_t action)
 645 {
 646   return action->comm.src_data;
 647 }
 648
 649 /**
 650  *  \brief Return the user data associated to the receiver of the communication
 651  *  \param action The communication
 652  *  \return the user data
 653  */
 654 void* SIMIX_comm_get_dst_data(smx_action_t action)
 655 {
 656   return action->comm.dst_data;
 657 }
 658
 659 void* SIMIX_comm_get_src_buff(smx_action_t action)
 660 {
 661   return action->comm.src_buff;
 662 }
 663
 664 void* SIMIX_comm_get_dst_buff(smx_action_t action)
 665 {
 666   return action->comm.dst_buff;
 667 }
 668
 669 size_t SIMIX_comm_get_src_buff_size(smx_action_t action)
 670 {
 671   return action->comm.src_buff_size;
 672 }
 673
 674 size_t SIMIX_comm_get_dst_buff_size(smx_action_t action)
 675 {
 676   size_t buff_size;
 677
 678   if (action->comm.dst_buff_size)
 679     buff_size = *(action->comm.dst_buff_size);
 680   else
 681     buff_size = 0;
 682
 683   return buff_size;
 684 }
 685
 686 smx_process_t SIMIX_comm_get_src_proc(smx_action_t action)
 687 {
 688   return action->comm.src_proc;
 689 }
 690
 691 smx_process_t SIMIX_comm_get_dst_proc(smx_action_t action)
 692 {
 693   return action->comm.dst_proc;
 694 }
 695
 696 #ifdef HAVE_LATENCY_BOUND_TRACKING
 697 /**
 698  *  \brief verify if communication is latency bounded
 699  *  \param comm The communication
 700  */
 701 XBT_INLINE int SIMIX_comm_is_latency_bounded(smx_action_t action)
 702 {
 703   if (action->comm.surf_comm){
 704       DEBUG1("Getting latency limited for surf_action (%p)", action->comm.surf_comm);
 705       action->latency_limited = surf_workstation_model->get_latency_limited(action->comm.surf_comm);
 706       DEBUG1("Action limited is %d", action->latency_limited);
 707   }
 708   return action->latency_limited;
 709 }
 710 #endif
 711
 712 /******************************************************************************/
 713 /*                    SIMIX_comm_copy_data callbacks                       */
 714 /******************************************************************************/
 715 static void (*SIMIX_comm_copy_data_callback) (smx_action_t, size_t) =
 716     &SIMIX_comm_copy_pointer_callback;
 717
 718 void
 719 SIMIX_comm_set_copy_data_callback(void (*callback) (smx_action_t, size_t))
 720 {
 721   SIMIX_comm_copy_data_callback = callback;
 722 }
 723
 724 void SIMIX_comm_copy_pointer_callback(smx_action_t comm, size_t buff_size)
 725 {
 726   xbt_assert1((buff_size == sizeof(void *)),
 727               "Cannot copy %zu bytes: must be sizeof(void*)", buff_size);
 728   *(void **) (comm->comm.dst_buff) = comm->comm.src_buff;
 729 }
 730
 731 void SIMIX_comm_copy_buffer_callback(smx_action_t comm, size_t buff_size)
 732 {
 733   memcpy(comm->comm.dst_buff, comm->comm.src_buff, buff_size);
 734 }
 735
 736 /**
 737  *  \brief Copy the communication data from the sender's buffer to the receiver's one
 738  *  \param comm The communication
 739  */
 740 void SIMIX_comm_copy_data(smx_action_t comm)
 741 {
 742   size_t buff_size = comm->comm.src_buff_size;
 743   /* If there is no data to be copy then return */
 744   if (!comm->comm.src_buff || !comm->comm.dst_buff || comm->comm.copied == 1)
 745     return;
 746
 747   DEBUG6("Copying comm %p data from %s (%p) -> %s (%p) (%zu bytes)",
 748          comm,
 749          comm->comm.src_proc->smx_host->name, comm->comm.src_buff,
 750          comm->comm.dst_proc->smx_host->name, comm->comm.dst_buff, buff_size);
 751
 752   /* Copy at most dst_buff_size bytes of the message to receiver's buffer */
 753   if (comm->comm.dst_buff_size)
 754     buff_size = MIN(buff_size, *(comm->comm.dst_buff_size));
 755
 756   /* Update the receiver's buffer size to the copied amount */
 757   if (comm->comm.dst_buff_size)
 758     *comm->comm.dst_buff_size = buff_size;
 759
 760   if (buff_size == 0)
 761     return;
 762
 763   (*SIMIX_comm_copy_data_callback) (comm, buff_size);
 764
 765   /* Set the copied flag so we copy data only once */
 766   /* (this function might be called from both communication ends) */
 767   comm->comm.copied = 1;
 768 }