src/simix/smx_process.c

   1 /* Copyright (c) 2007, 2008, 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 "smx_private.h"
   8 #include "xbt/sysdep.h"
   9 #include "xbt/log.h"
  10 #include "xbt/dict.h"
  11 #include "mc/mc.h"
  12
  13 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(simix_process, simix,
  14                                 "Logging specific to SIMIX (process)");
  15
  16 unsigned long simix_process_maxpid = 0;
  17
  18 /**
  19  * \brief Returns the current agent.
  20  *
  21  * This functions returns the currently running SIMIX process.
  22  *
  23  * \return The SIMIX process
  24  */
  25 XBT_INLINE smx_process_t SIMIX_process_self(void)
  26 {
  27   smx_context_t self_context = SIMIX_context_self();
  28
  29   return self_context ? SIMIX_context_get_data(self_context) : NULL;
  30 }
  31
  32 /**
  33  * \brief Returns whether a process has pending asynchronous communications.
  34  * \return true if there are asynchronous communications in this process
  35  */
  36 int SIMIX_process_has_pending_comms(smx_process_t process) {
  37
  38   return xbt_fifo_size(process->comms) > 0;
  39 }
  40
  41 /**
  42  * \brief Moves a process to the list of processes to destroy.
  43  */
  44 void SIMIX_process_cleanup(smx_process_t process)
  45 {
  46   XBT_DEBUG("Cleanup process %s (%p), waiting action %p",
  47       process->name, process, process->waiting_action);
  48
  49   /* cancel non-blocking communications */
  50   smx_action_t action;
  51   while ((action = xbt_fifo_pop(process->comms))) {
  52
  53     /* make sure no one will finish the comm after this process is destroyed,
  54      * because src_proc or dst_proc would be an invalid pointer */
  55     SIMIX_comm_cancel(action);
  56
  57     if (action->comm.src_proc == process) {
  58       XBT_DEBUG("Found an unfinished send comm %p (detached = %d), state %d, src = %p, dst = %p",
  59           action, action->comm.detached, (int)action->state, action->comm.src_proc, action->comm.dst_proc);
  60       action->comm.src_proc = NULL;
  61
  62       if (action->comm.detached) {
  63          if (action->comm.refcount == 0) {
  64            XBT_DEBUG("Increase the refcount before destroying it since it's detached");
  65            /* I'm not supposed to destroy a detached comm from the sender side,
  66             * unless there is no receiver matching the rdv */
  67            action->comm.refcount++;
  68            SIMIX_comm_destroy(action);
  69          }
  70          else {
  71            XBT_DEBUG("Don't destroy it since its refcount is %d", action->comm.refcount);
  72          }
  73       } else {
  74         SIMIX_comm_destroy(action);
  75       }
  76     }
  77     else if (action->comm.dst_proc == process){
  78       XBT_DEBUG("Found an unfinished recv comm %p, state %d, src = %p, dst = %p",
  79           action, (int)action->state, action->comm.src_proc, action->comm.dst_proc);
  80       action->comm.dst_proc = NULL;
  81
  82       if (action->comm.detached && action->comm.refcount == 1
  83           && action->comm.src_proc != NULL) {
  84         /* the comm will be freed right now, remove it from the sender */
  85         xbt_fifo_remove(action->comm.src_proc->comms, action);
  86       }
  87       SIMIX_comm_destroy(action);
  88     }
  89     else {
  90       xbt_die("Communication action %p is in my list but I'm not the sender "
  91           "or the receiver", action);
  92     }
  93   }
  94
  95   /*xbt_swag_remove(process, simix_global->process_to_run);*/
  96   xbt_swag_remove(process, simix_global->process_list);
  97   xbt_swag_remove(process, process->smx_host->process_list);
  98   xbt_swag_insert(process, simix_global->process_to_destroy);
  99   process->context->iwannadie = 0;
 100 }
 101
 102 /**
 103  * Garbage collection
 104  *
 105  * Should be called some time to time to free the memory allocated for processes
 106  * that have finished (or killed).
 107  */
 108 void SIMIX_process_empty_trash(void)
 109 {
 110   smx_process_t process = NULL;
 111
 112   while ((process = xbt_swag_extract(simix_global->process_to_destroy))) {
 113     SIMIX_context_free(process->context);
 114
 115     /* Free the exception allocated at creation time */
 116     free(process->running_ctx);
 117     xbt_dict_free(&process->properties);
 118
 119     xbt_fifo_free(process->comms);
 120
 121     free(process->name);
 122     free(process);
 123   }
 124 }
 125
 126 /**
 127  * \brief Creates and runs the maestro process
 128  */
 129 void SIMIX_create_maestro_process()
 130 {
 131   smx_process_t maestro = NULL;
 132
 133   /* Create maestro process and intilialize it */
 134   maestro = xbt_new0(s_smx_process_t, 1);
 135   maestro->pid = simix_process_maxpid++;
 136   maestro->name = (char *) "";
 137   maestro->running_ctx = xbt_new(xbt_running_ctx_t, 1);
 138   XBT_RUNNING_CTX_INITIALIZE(maestro->running_ctx);
 139   maestro->context = SIMIX_context_new(NULL, 0, NULL, NULL, maestro);
 140   maestro->simcall.issuer = maestro;
 141
 142   simix_global->maestro_process = maestro;
 143   return;
 144 }
 145
 146 /**
 147  * \brief Same as SIMIX_process_create() but with only one argument (used by timers).
 148  * \return the process created
 149  */
 150 smx_process_t SIMIX_process_create_from_wrapper(smx_process_arg_t args) {
 151
 152   smx_process_t process;
 153   simix_global->create_process_function(
 154       &process,
 155       args->name,
 156       args->code,
 157       args->data,
 158       args->hostname,
 159       args->kill_time,
 160       args->argc,
 161       args->argv,
 162       args->properties);
 163
 164   return process;
 165 }
 166
 167 /**
 168  * \brief Internal function to create a process.
 169  *
 170  * This function actually creates the process.
 171  * It may be called when a SIMCALL_PROCESS_CREATE simcall occurs,
 172  * or directly for SIMIX internal purposes.
 173  *
 174  * \return the process created
 175  */
 176 void SIMIX_process_create(smx_process_t *process,
 177                           const char *name,
 178                           xbt_main_func_t code,
 179                           void *data,
 180                           const char *hostname,
 181                           double kill_time,
 182                           int argc, char **argv,
 183                           xbt_dict_t properties) {
 184
 185   *process = NULL;
 186   smx_host_t host = SIMIX_host_get_by_name(hostname);
 187
 188   XBT_DEBUG("Start process %s on host %s", name, hostname);
 189
 190   if (!SIMIX_host_get_state(host)) {
 191     XBT_WARN("Cannot launch process '%s' on failed host '%s'", name,
 192           hostname);
 193   }
 194   else {
 195     *process = xbt_new0(s_smx_process_t, 1);
 196
 197     xbt_assert(((code != NULL) && (host != NULL)), "Invalid parameters");
 198
 199     /* Process data */
 200     (*process)->pid = simix_process_maxpid++;
 201     (*process)->name = xbt_strdup(name);
 202     (*process)->smx_host = host;
 203     (*process)->data = data;
 204     (*process)->comms = xbt_fifo_new();
 205     (*process)->simcall.issuer = *process;
 206
 207     XBT_VERB("Create context %s", (*process)->name);
 208     (*process)->context = SIMIX_context_new(code, argc, argv,
 209         simix_global->cleanup_process_function, *process);
 210
 211     (*process)->running_ctx = xbt_new(xbt_running_ctx_t, 1);
 212     XBT_RUNNING_CTX_INITIALIZE((*process)->running_ctx);
 213
 214     /* Add properties */
 215     (*process)->properties = properties;
 216
 217     /* Add the process to it's host process list */
 218     xbt_swag_insert(*process, host->process_list);
 219
 220     XBT_DEBUG("Start context '%s'", (*process)->name);
 221
 222     /* Now insert it in the global process list and in the process to run list */
 223     xbt_swag_insert(*process, simix_global->process_list);
 224     XBT_DEBUG("Inserting %s(%s) in the to_run list", (*process)->name, host->name);
 225     xbt_dynar_push_as(simix_global->process_to_run, smx_process_t, *process);
 226   }
 227
 228   if (kill_time > SIMIX_get_clock()) {
 229     if (simix_global->kill_process_function) {
 230       XBT_DEBUG("Process %s(%s) will be kill at time %f", (*process)->name,
 231           (*process)->smx_host->name, kill_time);
 232       SIMIX_timer_set(kill_time, simix_global->kill_process_function, *process);
 233     }
 234   }
 235 }
 236
 237 /**
 238  * \brief Executes the processes from simix_global->process_to_run.
 239  *
 240  * The processes of simix_global->process_to_run are run (in parallel if
 241  * possible).  On exit, simix_global->process_to_run is empty, and
 242  * simix_global->process_that_ran contains the list of processes that just ran.
 243  * The two lists are swapped so, be careful when using them before and after a
 244  * call to this function.
 245  */
 246 void SIMIX_process_runall(void)
 247 {
 248   SIMIX_context_runall();
 249
 250   xbt_dynar_t tmp = simix_global->process_that_ran;
 251   simix_global->process_that_ran = simix_global->process_to_run;
 252   simix_global->process_to_run = tmp;
 253   xbt_dynar_reset(simix_global->process_to_run);
 254 }
 255
 256 /**
 257  * \brief Internal function to kill a SIMIX process.
 258  *
 259  * This function may be called when a SIMCALL_PROCESS_KILL simcall occurs,
 260  * or directly for SIMIX internal purposes.
 261  *
 262  * \param process poor victim
 263  */
 264 void SIMIX_process_kill(smx_process_t process) {
 265
 266   XBT_DEBUG("Killing process %s on %s", process->name, process->smx_host->name);
 267
 268   process->context->iwannadie = 1;
 269   process->blocked = 0;
 270   process->suspended = 0;
 271   /* FIXME: set doexception to 0 also? */
 272
 273   /* destroy the blocking action if any */
 274   if (process->waiting_action) {
 275
 276     switch (process->waiting_action->type) {
 277
 278       case SIMIX_ACTION_EXECUTE:
 279       case SIMIX_ACTION_PARALLEL_EXECUTE:
 280         SIMIX_host_execution_destroy(process->waiting_action);
 281         break;
 282
 283       case SIMIX_ACTION_COMMUNICATE:
 284         xbt_fifo_remove(process->comms, process->waiting_action);
 285         SIMIX_comm_destroy(process->waiting_action);
 286         break;
 287
 288       case SIMIX_ACTION_SLEEP:
 289         SIMIX_process_sleep_destroy(process->waiting_action);
 290         break;
 291
 292       case SIMIX_ACTION_SYNCHRO:
 293         SIMIX_synchro_stop_waiting(process, &process->simcall);
 294         SIMIX_synchro_destroy(process->waiting_action);
 295         break;
 296
 297       case SIMIX_ACTION_IO:
 298         SIMIX_io_destroy(process->waiting_action);
 299         break;
 300     }
 301   }
 302   if(!xbt_dynar_member(simix_global->process_to_run, &(process)))
 303     xbt_dynar_push_as(simix_global->process_to_run, smx_process_t, process);
 304 }
 305
 306 /**
 307  * \brief Kills all running processes.
 308  * \param issuer this one will not be killed
 309  */
 310 void SIMIX_process_killall(smx_process_t issuer)
 311 {
 312   smx_process_t p = NULL;
 313
 314   while ((p = xbt_swag_extract(simix_global->process_list))) {
 315     if (p != issuer) {
 316       SIMIX_process_kill(p);
 317     }
 318   }
 319
 320   SIMIX_context_runall();
 321
 322   SIMIX_process_empty_trash();
 323 }
 324
 325 void SIMIX_process_change_host(smx_process_t process,
 326                                smx_host_t dest)
 327 {
 328   xbt_assert((process != NULL), "Invalid parameters");
 329   xbt_swag_remove(process, process->smx_host->process_list);
 330   process->smx_host = dest;
 331   xbt_swag_insert(process, dest->process_list);
 332 }
 333
 334 void SIMIX_pre_process_change_host(smx_process_t process, smx_host_t dest)
 335 {
 336   process->new_host = dest;
 337 }
 338
 339 void SIMIX_pre_process_suspend(smx_simcall_t simcall)
 340 {
 341   smx_process_t process = simcall->process_suspend.process;
 342   smx_action_t action_suspend =
 343       SIMIX_process_suspend(process, simcall->issuer);
 344
 345   if (process != simcall->issuer) {
 346     SIMIX_simcall_answer(simcall);
 347   } else {
 348     xbt_fifo_push(action_suspend->simcalls, simcall);
 349     process->waiting_action = action_suspend;
 350     SIMIX_host_execution_suspend(process->waiting_action);
 351   }
 352   /* If we are suspending ourselves, then just do not finish the simcall now */
 353 }
 354
 355 smx_action_t SIMIX_process_suspend(smx_process_t process, smx_process_t issuer)
 356 {
 357   xbt_assert((process != NULL), "Invalid parameters");
 358
 359   if (process->suspended) {
 360     XBT_DEBUG("Process '%s' is already suspended", process->name);
 361     return NULL;
 362   }
 363
 364   process->suspended = 1;
 365
 366   /* If we are suspending another process, and it is waiting on an action,
 367      suspend its action. */
 368   if (process != issuer) {
 369
 370     if (process->waiting_action) {
 371
 372       switch (process->waiting_action->type) {
 373
 374         case SIMIX_ACTION_EXECUTE:
 375         case SIMIX_ACTION_PARALLEL_EXECUTE:
 376           SIMIX_host_execution_suspend(process->waiting_action);
 377           break;
 378
 379         case SIMIX_ACTION_COMMUNICATE:
 380           SIMIX_comm_suspend(process->waiting_action);
 381           break;
 382
 383         case SIMIX_ACTION_SLEEP:
 384           SIMIX_process_sleep_suspend(process->waiting_action);
 385           break;
 386
 387         default:
 388           xbt_die("Internal error in SIMIX_process_suspend: unexpected action type %d",
 389               (int)process->waiting_action->type);
 390       }
 391       return NULL;
 392     } else {
 393       /* Suspension is delayed to when the process is rescheduled. */
 394       return NULL;
 395     }
 396   } else {
 397     return SIMIX_host_execute("suspend", process->smx_host, 0.0, 1.0);
 398   }
 399 }
 400
 401 void SIMIX_process_resume(smx_process_t process, smx_process_t issuer)
 402 {
 403   xbt_assert((process != NULL), "Invalid parameters");
 404
 405   XBT_IN("process = %p, issuer = %p", process, issuer);
 406
 407   if(process->context->iwannadie)
 408     return;
 409
 410   if(!process->suspended) return;
 411   process->suspended = 0;
 412
 413   /* If we are resuming another process, resume the action it was waiting for
 414      if any. Otherwise add it to the list of process to run in the next round. */
 415   if (process != issuer) {
 416
 417     if (process->waiting_action) {
 418
 419       switch (process->waiting_action->type) {
 420
 421         case SIMIX_ACTION_EXECUTE:
 422         case SIMIX_ACTION_PARALLEL_EXECUTE:
 423           SIMIX_host_execution_resume(process->waiting_action);
 424           break;
 425
 426         case SIMIX_ACTION_COMMUNICATE:
 427           SIMIX_comm_resume(process->waiting_action);
 428           break;
 429
 430         case SIMIX_ACTION_SLEEP:
 431           SIMIX_process_sleep_resume(process->waiting_action);
 432           break;
 433
 434         default:
 435           xbt_die("Internal error in SIMIX_process_resume: unexpected action type %d",
 436               (int)process->waiting_action->type);
 437       }
 438     }
 439     else
 440       XBT_WARN("Strange. Process %p is trying to resume himself.", issuer);
 441   }
 442   XBT_OUT();
 443 }
 444
 445 int SIMIX_process_get_maxpid(void) {
 446   return simix_process_maxpid;
 447 }
 448
 449 int SIMIX_process_count(void)
 450 {
 451   return xbt_swag_size(simix_global->process_list);
 452 }
 453
 454 void* SIMIX_process_self_get_data(smx_process_t self)
 455 {
 456   xbt_assert(self == SIMIX_process_self(), "This is not the current process");
 457
 458   if (!self) {
 459     return NULL;
 460   }
 461   return SIMIX_process_get_data(self);
 462 }
 463
 464 void SIMIX_process_self_set_data(smx_process_t self, void *data)
 465 {
 466   xbt_assert(self == SIMIX_process_self(), "This is not the current process");
 467
 468   SIMIX_process_set_data(self, data);
 469 }
 470
 471 void* SIMIX_process_get_data(smx_process_t process)
 472 {
 473   return process->data;
 474 }
 475
 476 void SIMIX_process_set_data(smx_process_t process, void *data)
 477 {
 478   process->data = data;
 479 }
 480
 481 smx_host_t SIMIX_process_get_host(smx_process_t process)
 482 {
 483   return process->smx_host;
 484 }
 485
 486 /* needs to be public and without simcall because it is called
 487    by exceptions and logging events */
 488 const char* SIMIX_process_self_get_name(void) {
 489
 490   smx_process_t process = SIMIX_process_self();
 491   if (process == NULL || process == simix_global->maestro_process)
 492     return "";
 493
 494   return SIMIX_process_get_name(process);
 495 }
 496
 497 const char* SIMIX_process_get_name(smx_process_t process)
 498 {
 499   return process->name;
 500 }
 501
 502 smx_process_t SIMIX_process_get_by_name(const char* name)
 503 {
 504   smx_process_t proc;
 505
 506   xbt_swag_foreach(proc, simix_global->process_list)
 507   {
 508     if(!strcmp(name, proc->name))
 509       return proc;
 510   }
 511   return NULL;
 512 }
 513
 514 int SIMIX_process_is_suspended(smx_process_t process)
 515 {
 516   return process->suspended;
 517 }
 518
 519 xbt_dict_t SIMIX_process_get_properties(smx_process_t process)
 520 {
 521   return process->properties;
 522 }
 523
 524 void SIMIX_pre_process_sleep(smx_simcall_t simcall)
 525 {
 526   if (MC_IS_ENABLED) {
 527     MC_process_clock_add(simcall->issuer, simcall->process_sleep.duration);
 528     simcall->process_sleep.result = SIMIX_DONE;
 529     SIMIX_simcall_answer(simcall);
 530     return;
 531   }
 532   smx_action_t action = SIMIX_process_sleep(simcall->issuer, simcall->process_sleep.duration);
 533   xbt_fifo_push(action->simcalls, simcall);
 534   simcall->issuer->waiting_action = action;
 535 }
 536
 537 smx_action_t SIMIX_process_sleep(smx_process_t process, double duration)
 538 {
 539   smx_action_t action;
 540   smx_host_t host = process->smx_host;
 541
 542   /* check if the host is active */
 543   if (surf_workstation_model->extension.
 544       workstation.get_state(host->host) != SURF_RESOURCE_ON) {
 545     THROWF(host_error, 0, "Host %s failed, you cannot call this function",
 546            host->name);
 547   }
 548
 549   action = xbt_mallocator_get(simix_global->action_mallocator);
 550   action->type = SIMIX_ACTION_SLEEP;
 551   action->name = NULL;
 552 #ifdef HAVE_TRACING
 553   action->category = NULL;
 554 #endif
 555
 556   action->sleep.host = host;
 557   action->sleep.surf_sleep =
 558       surf_workstation_model->extension.workstation.sleep(host->host, duration);
 559
 560   surf_workstation_model->action_data_set(action->sleep.surf_sleep, action);
 561   XBT_DEBUG("Create sleep action %p", action);
 562
 563   return action;
 564 }
 565
 566 void SIMIX_post_process_sleep(smx_action_t action)
 567 {
 568   smx_simcall_t simcall;
 569   e_smx_state_t state;
 570
 571   while ((simcall = xbt_fifo_shift(action->simcalls))) {
 572
 573     switch(surf_workstation_model->action_state_get(action->sleep.surf_sleep)){
 574       case SURF_ACTION_FAILED:
 575         state = SIMIX_SRC_HOST_FAILURE;
 576         break;
 577
 578       case SURF_ACTION_DONE:
 579         state = SIMIX_DONE;
 580         break;
 581
 582       default:
 583         THROW_IMPOSSIBLE;
 584         break;
 585     }
 586     simcall->process_sleep.result = state;
 587     simcall->issuer->waiting_action = NULL;
 588     SIMIX_simcall_answer(simcall);
 589   }
 590   SIMIX_process_sleep_destroy(action);
 591 }
 592
 593 void SIMIX_process_sleep_destroy(smx_action_t action)
 594 {
 595   XBT_DEBUG("Destroy action %p", action);
 596   if (action->sleep.surf_sleep)
 597     action->sleep.surf_sleep->model_type->action_unref(action->sleep.surf_sleep);
 598   xbt_mallocator_release(simix_global->action_mallocator, action);
 599 }
 600
 601 void SIMIX_process_sleep_suspend(smx_action_t action)
 602 {
 603   surf_workstation_model->suspend(action->sleep.surf_sleep);
 604 }
 605
 606 void SIMIX_process_sleep_resume(smx_action_t action)
 607 {
 608   surf_workstation_model->resume(action->sleep.surf_sleep);
 609 }
 610
 611 /**
 612  * \brief Calling this function makes the process to yield.
 613  *
 614  * Only the current process can call this function, giving back the control to
 615  * maestro.
 616  *
 617  * \param self the current process
 618  */
 619 void SIMIX_process_yield(smx_process_t self)
 620 {
 621   XBT_DEBUG("Yield process '%s'", self->name);
 622
 623   /* Go into sleep and return control to maestro */
 624   SIMIX_context_suspend(self->context);
 625
 626   /* Ok, maestro returned control to us */
 627   XBT_DEBUG("Control returned to me: '%s'", self->name);
 628
 629   if (self->context->iwannadie){
 630     XBT_DEBUG("I wanna die!");
 631     SIMIX_context_stop(self->context);
 632   }
 633
 634   if(self->suspended) {
 635     xbt_assert(!self->doexception, "Gloups! This exception may be lost by subsequent calls.");
 636     self->suspended = 0;
 637     SIMIX_process_suspend(self,self);
 638   }
 639
 640   if (self->doexception) {
 641     XBT_DEBUG("Wait, maestro left me an exception");
 642     self->doexception = 0;
 643     SMX_THROW();
 644   }
 645
 646   if (self->new_host) {
 647     SIMIX_process_change_host(self, self->new_host);
 648     self->new_host = NULL;
 649   }
 650 }
 651
 652 /* callback: context fetching */
 653 xbt_running_ctx_t *SIMIX_process_get_running_context(void)
 654 {
 655   return SIMIX_process_self()->running_ctx;
 656 }
 657
 658 /* callback: termination */
 659 void SIMIX_process_exception_terminate(xbt_ex_t * e)
 660 {
 661   xbt_ex_display(e);
 662   abort();
 663 }
 664
 665 smx_context_t SIMIX_process_get_context(smx_process_t p) {
 666   return p->context;
 667 }
 668
 669 void SIMIX_process_set_context(smx_process_t p,smx_context_t c) {
 670   p->context = c;
 671 }
 672
 673 /**
 674  * \brief Returns the list of processes to run.
 675  */
 676 xbt_dynar_t SIMIX_process_get_runnable(void)
 677 {
 678   return simix_global->process_to_run;
 679 }
 680
 681 /**
 682  * \brief Returns the process from PID.
 683  */
 684 smx_process_t SIMIX_process_from_PID(int PID)
 685 {
 686         smx_process_t proc;
 687         xbt_swag_foreach(proc, simix_global->process_list)
 688         {
 689          if(proc->pid == PID)
 690          return proc;
 691         }
 692         return NULL;
 693 }
 694
 695 /** @brief returns a dynar containg all currently existing processes */
 696 xbt_dynar_t SIMIX_processes_as_dynar(void) {
 697   smx_process_t proc;
 698   xbt_dynar_t res = xbt_dynar_new(sizeof(smx_process_t),NULL);
 699   xbt_swag_foreach(proc, simix_global->process_list) {
 700     xbt_dynar_push(res,&proc);
 701   }
 702   return res;
 703 }