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[simgrid.git] / src / simix / smx_process.c
1 /* Copyright (c) 2007-2012. 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 void SIMIX_pre_process_cleanup(smx_simcall_t simcall, smx_process_t process) {
42   SIMIX_process_cleanup(process);
43 }
44 /**
45  * \brief Moves a process to the list of processes to destroy.
46  */
47 void SIMIX_process_cleanup(smx_process_t process)
48 {
49   XBT_DEBUG("Cleanup process %s (%p), waiting action %p",
50       process->name, process, process->waiting_action);
51
52   /* cancel non-blocking communications */
53   smx_action_t action;
54   while ((action = xbt_fifo_pop(process->comms))) {
55
56     /* make sure no one will finish the comm after this process is destroyed,
57      * because src_proc or dst_proc would be an invalid pointer */
58     SIMIX_comm_cancel(action);
59
60     if (action->comm.src_proc == process) {
61       XBT_DEBUG("Found an unfinished send comm %p (detached = %d), state %d, src = %p, dst = %p",
62           action, action->comm.detached, (int)action->state, action->comm.src_proc, action->comm.dst_proc);
63       action->comm.src_proc = NULL;
64
65       if (action->comm.detached) {
66          if (action->comm.refcount == 0) {
67            XBT_DEBUG("Increase the refcount before destroying it since it's detached");
68            /* I'm not supposed to destroy a detached comm from the sender side,
69             * unless there is no receiver matching the rdv */
70            action->comm.refcount++;
71            SIMIX_comm_destroy(action);
72          }
73          else {
74            XBT_DEBUG("Don't destroy it since its refcount is %d", action->comm.refcount);
75          }
76       } else {
77         SIMIX_comm_destroy(action);
78       }
79     }
80     else if (action->comm.dst_proc == process){
81       XBT_DEBUG("Found an unfinished recv comm %p, state %d, src = %p, dst = %p",
82           action, (int)action->state, action->comm.src_proc, action->comm.dst_proc);
83       action->comm.dst_proc = NULL;
84
85       if (action->comm.detached && action->comm.refcount == 1
86           && action->comm.src_proc != NULL) {
87         /* the comm will be freed right now, remove it from the sender */
88         xbt_fifo_remove(action->comm.src_proc->comms, action);
89       }
90       SIMIX_comm_destroy(action);
91     }
92     else {
93       xbt_die("Communication action %p is in my list but I'm not the sender "
94           "or the receiver", action);
95     }
96   }
97
98   /*xbt_swag_remove(process, simix_global->process_to_run);*/
99   xbt_swag_remove(process, simix_global->process_list);
100   xbt_swag_remove(process, SIMIX_host_priv(process->smx_host)->process_list);
101   xbt_swag_insert(process, simix_global->process_to_destroy);
102   process->context->iwannadie = 0;
103 }
104
105 /** 
106  * Garbage collection
107  *
108  * Should be called some time to time to free the memory allocated for processes
109  * that have finished (or killed).
110  */
111 void SIMIX_process_empty_trash(void)
112 {
113   smx_process_t process = NULL;
114
115   while ((process = xbt_swag_extract(simix_global->process_to_destroy))) {
116     SIMIX_context_free(process->context);
117
118     /* Free the exception allocated at creation time */
119     free(process->running_ctx);
120     xbt_dict_free(&process->properties);
121
122     xbt_fifo_free(process->comms);
123
124     xbt_dynar_free(&process->on_exit);
125
126     free(process->name);
127     free(process);
128   }
129 }
130
131 /**
132  * \brief Creates and runs the maestro process
133  */
134 void SIMIX_create_maestro_process()
135 {
136   smx_process_t maestro = NULL;
137
138   /* Create maestro process and intilialize it */
139   maestro = xbt_new0(s_smx_process_t, 1);
140   maestro->pid = simix_process_maxpid++;
141   maestro->name = (char *) "";
142   maestro->running_ctx = xbt_new(xbt_running_ctx_t, 1);
143   XBT_RUNNING_CTX_INITIALIZE(maestro->running_ctx);
144   maestro->context = SIMIX_context_new(NULL, 0, NULL, NULL, maestro);
145   maestro->simcall.issuer = maestro;
146
147   if (SIMIX_process_self()) {
148     maestro->ppid = SIMIX_process_get_PID(SIMIX_process_self());
149   } else {
150     maestro->ppid = -1;
151   }
152
153   simix_global->maestro_process = maestro;
154   return;
155 }
156 /**
157  * \brief Stops a process.
158  *
159  * Stops the process, execute all the registered on_exit functions,
160  * register it to the list of the process to restart if needed
161  * and stops its context.
162  */
163 void SIMIX_process_stop(smx_process_t arg) {
164   /* execute the on_exit functions */
165   SIMIX_process_on_exit_runall(arg);
166   /* Add the process to the list of process to restart, only if
167    * the host is down
168    */
169   if (arg->auto_restart && !SIMIX_host_get_state(arg->smx_host)) {
170     SIMIX_host_add_auto_restart_process(arg->smx_host,arg->name,arg->code, arg->data,
171                                         sg_host_name(arg->smx_host),
172                                         arg->kill_time,
173                                         arg->argc,arg->argv,arg->properties,
174                                         arg->auto_restart);
175   }
176   XBT_DEBUG("Process %s (%s) is dead",arg->name,sg_host_name(arg->smx_host));
177   /* stop the context */
178   SIMIX_context_stop(arg->context);
179 }
180
181 /**
182  * \brief Same as SIMIX_process_create() but with only one argument (used by timers).
183  * This function frees the argument.
184  * \return the process created
185  */
186 smx_process_t SIMIX_process_create_from_wrapper(smx_process_arg_t args) {
187
188   smx_process_t process;
189   simix_global->create_process_function(
190       &process,
191       args->name,
192       args->code,
193       args->data,
194       args->hostname,
195       args->kill_time,
196       args->argc,
197       args->argv,
198       args->properties,
199       args->auto_restart);
200   xbt_free(args);
201   return process;
202 }
203
204
205 void SIMIX_pre_process_create(smx_simcall_t simcall,
206                           smx_process_t *process,
207                           const char *name,
208                           xbt_main_func_t code,
209                           void *data,
210                           const char *hostname,
211                           double kill_time,
212                           int argc, char **argv,
213                           xbt_dict_t properties,
214                           int auto_restart){
215   return SIMIX_process_create(process, name, code, data, hostname,
216                               kill_time, argc, argv, properties, auto_restart);
217 }
218 /**
219  * \brief Internal function to create a process.
220  *
221  * This function actually creates the process.
222  * It may be called when a SIMCALL_PROCESS_CREATE simcall occurs,
223  * or directly for SIMIX internal purposes. The sure thing is that it's called from maestro context.
224  *
225  * \return the process created
226  */
227 void SIMIX_process_create(smx_process_t *process,
228                           const char *name,
229                           xbt_main_func_t code,
230                           void *data,
231                           const char *hostname,
232                           double kill_time,
233                           int argc, char **argv,
234                           xbt_dict_t properties,
235                           int auto_restart) {
236
237   *process = NULL;
238   smx_host_t host = SIMIX_host_get_by_name(hostname);
239
240   XBT_DEBUG("Start process %s on host '%s'", name, hostname);
241
242   if (!SIMIX_host_get_state(host)) {
243     XBT_WARN("Cannot launch process '%s' on failed host '%s'", name,
244           hostname);
245   }
246   else {
247     *process = xbt_new0(s_smx_process_t, 1);
248
249     xbt_assert(((code != NULL) && (host != NULL)), "Invalid parameters");
250     /* Process data */
251     (*process)->pid = simix_process_maxpid++;
252     (*process)->name = xbt_strdup(name);
253     (*process)->smx_host = host;
254     (*process)->data = data;
255     (*process)->comms = xbt_fifo_new();
256     (*process)->simcall.issuer = *process;
257     
258      if (SIMIX_process_self()) {
259        (*process)->ppid = SIMIX_process_get_PID(SIMIX_process_self());
260      } else {
261        (*process)->ppid = -1;
262      }
263
264     /* Process data for auto-restart */
265     (*process)->auto_restart = auto_restart;
266     (*process)->code = code;
267     (*process)->argc = argc;
268     (*process)->argv = argv;
269     (*process)->kill_time = kill_time;
270
271
272     XBT_VERB("Create context %s", (*process)->name);
273     (*process)->context = SIMIX_context_new(code, argc, argv,
274       simix_global->cleanup_process_function, *process);
275
276     (*process)->running_ctx = xbt_new(xbt_running_ctx_t, 1);
277     XBT_RUNNING_CTX_INITIALIZE((*process)->running_ctx);
278
279     /* Add properties */
280     (*process)->properties = properties;
281
282     /* Add the process to it's host process list */
283     xbt_swag_insert(*process, SIMIX_host_priv(host)->process_list);
284
285     XBT_DEBUG("Start context '%s'", (*process)->name);
286
287     /* Now insert it in the global process list and in the process to run list */
288     xbt_swag_insert(*process, simix_global->process_list);
289     XBT_DEBUG("Inserting %s(%s) in the to_run list", (*process)->name, sg_host_name(host));
290     xbt_dynar_push_as(simix_global->process_to_run, smx_process_t, *process);
291   }
292
293   if (kill_time > SIMIX_get_clock()) {
294     if (simix_global->kill_process_function) {
295       XBT_DEBUG("Process %s(%s) will be kill at time %f", (*process)->name,
296           sg_host_name((*process)->smx_host), kill_time);
297       SIMIX_timer_set(kill_time, simix_global->kill_process_function, *process);
298     }
299   }
300 }
301
302 /**
303  * \brief Executes the processes from simix_global->process_to_run.
304  *
305  * The processes of simix_global->process_to_run are run (in parallel if
306  * possible).  On exit, simix_global->process_to_run is empty, and
307  * simix_global->process_that_ran contains the list of processes that just ran.
308  * The two lists are swapped so, be careful when using them before and after a
309  * call to this function.
310  */
311 void SIMIX_process_runall(void)
312 {
313   SIMIX_context_runall();
314
315   xbt_dynar_t tmp = simix_global->process_that_ran;
316   simix_global->process_that_ran = simix_global->process_to_run;
317   simix_global->process_to_run = tmp;
318   xbt_dynar_reset(simix_global->process_to_run);
319 }
320
321 void SIMIX_pre_process_kill(smx_simcall_t simcall, smx_process_t process) {
322   SIMIX_process_kill(process, simcall->issuer);
323 }
324 /**
325  * \brief Internal function to kill a SIMIX process.
326  *
327  * This function may be called when a SIMCALL_PROCESS_KILL simcall occurs,
328  * or directly for SIMIX internal purposes.
329  *
330  * \param process poor victim
331  * \param issuer the process which has sent the PROCESS_KILL. Important to not schedule twice the same process.
332  */
333 void SIMIX_process_kill(smx_process_t process, smx_process_t issuer) {
334
335   XBT_DEBUG("Killing process %s on %s", process->name, sg_host_name(process->smx_host));
336
337   process->context->iwannadie = 1;
338   process->blocked = 0;
339   process->suspended = 0;
340   /* FIXME: set doexception to 0 also? */
341
342   /* destroy the blocking action if any */
343   if (process->waiting_action) {
344
345     switch (process->waiting_action->type) {
346
347       case SIMIX_ACTION_EXECUTE:          
348       case SIMIX_ACTION_PARALLEL_EXECUTE:
349         SIMIX_host_execution_destroy(process->waiting_action);
350         break;
351
352       case SIMIX_ACTION_COMMUNICATE:
353         xbt_fifo_remove(process->comms, process->waiting_action);
354         SIMIX_comm_cancel(process->waiting_action);
355         break;
356
357         case SIMIX_ACTION_SLEEP:
358           SIMIX_process_sleep_destroy(process->waiting_action);
359           break;
360
361         case SIMIX_ACTION_SYNCHRO:
362           SIMIX_synchro_stop_waiting(process, &process->simcall);
363           SIMIX_synchro_destroy(process->waiting_action);
364           break;
365
366         case SIMIX_ACTION_IO:
367           SIMIX_io_destroy(process->waiting_action);
368           break;
369
370         /* **************************************/
371         /* TUTORIAL: New API                    */
372         case SIMIX_ACTION_NEW_API:
373           SIMIX_new_api_destroy(process->waiting_action);
374           break;
375         /* **************************************/
376
377     }
378   }
379   if(!xbt_dynar_member(simix_global->process_to_run, &(process)) && process != issuer) {
380     xbt_dynar_push_as(simix_global->process_to_run, smx_process_t, process);
381   }
382
383 }
384
385 void SIMIX_pre_process_killall(smx_simcall_t simcall, int reset_pid) {
386   SIMIX_process_killall(simcall->issuer, reset_pid);
387 }
388 /**
389  * \brief Kills all running processes.
390  * \param issuer this one will not be killed
391  */
392 void SIMIX_process_killall(smx_process_t issuer, int reset_pid)
393 {
394   smx_process_t p = NULL;
395
396   while ((p = xbt_swag_extract(simix_global->process_list))) {
397     if (p != issuer) {
398       SIMIX_process_kill(p,issuer);
399     }
400   }
401
402   if (reset_pid > 0)
403     simix_process_maxpid = reset_pid;
404
405   SIMIX_context_runall();
406
407   SIMIX_process_empty_trash();
408 }
409
410 void SIMIX_pre_process_change_host(smx_simcall_t simcall, smx_process_t process,
411                                    smx_host_t dest)
412 {
413   process->new_host = dest;
414 }
415 void SIMIX_process_change_host(smx_process_t process,
416              smx_host_t dest)
417 {
418   xbt_assert((process != NULL), "Invalid parameters");
419   xbt_swag_remove(process, SIMIX_host_priv(process->smx_host)->process_list);
420   process->smx_host = dest;
421   xbt_swag_insert(process, SIMIX_host_priv(dest)->process_list);
422 }
423
424
425 void SIMIX_pre_process_suspend(smx_simcall_t simcall, smx_process_t process)
426 {
427   smx_action_t action_suspend =
428       SIMIX_process_suspend(process, simcall->issuer);
429
430   if (process != simcall->issuer) {
431     SIMIX_simcall_answer(simcall);
432   } else {
433     xbt_fifo_push(action_suspend->simcalls, simcall);
434     process->waiting_action = action_suspend;
435     SIMIX_host_execution_suspend(process->waiting_action);
436   }
437   /* If we are suspending ourselves, then just do not finish the simcall now */
438 }
439
440 smx_action_t SIMIX_process_suspend(smx_process_t process, smx_process_t issuer)
441 {
442   xbt_assert((process != NULL), "Invalid parameters");
443
444   if (process->suspended) {
445     XBT_DEBUG("Process '%s' is already suspended", process->name);
446     return NULL;
447   }
448
449   process->suspended = 1;
450
451   /* If we are suspending another process, and it is waiting on an action,
452      suspend its action. */
453   if (process != issuer) {
454
455     if (process->waiting_action) {
456
457       switch (process->waiting_action->type) {
458
459         case SIMIX_ACTION_EXECUTE:
460         case SIMIX_ACTION_PARALLEL_EXECUTE:
461           SIMIX_host_execution_suspend(process->waiting_action);
462           break;
463
464         case SIMIX_ACTION_COMMUNICATE:
465           SIMIX_comm_suspend(process->waiting_action);
466           break;
467
468         case SIMIX_ACTION_SLEEP:
469           SIMIX_process_sleep_suspend(process->waiting_action);
470           break;
471
472         case SIMIX_ACTION_SYNCHRO:
473           /* Suspension is delayed to when the process is rescheduled. */
474           break;
475
476         default:
477           xbt_die("Internal error in SIMIX_process_suspend: unexpected action type %d",
478               (int)process->waiting_action->type);
479       }
480       return NULL;
481     } else {
482       /* Suspension is delayed to when the process is rescheduled. */
483       return NULL;
484     }
485   } else {
486     return SIMIX_host_execute("suspend", process->smx_host, 0.0, 1.0);
487   }
488 }
489
490 void SIMIX_pre_process_resume(smx_simcall_t simcall, smx_process_t process){
491   SIMIX_process_resume(process, simcall->issuer);
492 }
493
494 void SIMIX_process_resume(smx_process_t process, smx_process_t issuer)
495 {
496   xbt_assert((process != NULL), "Invalid parameters");
497
498   XBT_IN("process = %p, issuer = %p", process, issuer);
499
500   if(process->context->iwannadie) {
501     XBT_VERB("Ignoring request to suspend a process that is currently dying.");
502     return;
503   }
504
505   if(!process->suspended) return;
506   process->suspended = 0;
507
508   /* If we are resuming another process, resume the action it was waiting for
509      if any. Otherwise add it to the list of process to run in the next round. */
510   if (process != issuer) {
511
512     if (process->waiting_action) {
513
514       switch (process->waiting_action->type) {
515
516         case SIMIX_ACTION_EXECUTE:          
517         case SIMIX_ACTION_PARALLEL_EXECUTE:
518           SIMIX_host_execution_resume(process->waiting_action);
519           break;
520
521         case SIMIX_ACTION_COMMUNICATE:
522           SIMIX_comm_resume(process->waiting_action);
523           break;
524
525         case SIMIX_ACTION_SLEEP:
526           SIMIX_process_sleep_resume(process->waiting_action);
527           break;
528
529         case SIMIX_ACTION_SYNCHRO:
530           /* I cannot resume it now. This is delayed to when the process is rescheduled at
531            * the end of the synchro. */
532           break;
533
534         default:
535           xbt_die("Internal error in SIMIX_process_resume: unexpected action type %d",
536               (int)process->waiting_action->type);
537       }
538     }
539   } else XBT_WARN("Strange. Process %p is trying to resume himself.", issuer);
540
541   XBT_OUT();
542 }
543
544 int SIMIX_process_get_maxpid(void) {
545   return simix_process_maxpid;
546 }
547
548 int SIMIX_pre_process_count(smx_simcall_t simcall){
549   return SIMIX_process_count();
550 }
551 int SIMIX_process_count(void)
552 {
553   return xbt_swag_size(simix_global->process_list);
554 }
555
556 int SIMIX_pre_process_get_PID(smx_simcall_t simcall, smx_process_t self){
557    return SIMIX_process_get_PID(self);
558 }
559
560 int SIMIX_process_get_PID(smx_process_t self){
561   if (self == NULL)
562     return 0;
563   else
564     return self->pid;
565 }
566
567 int SIMIX_pre_process_get_PPID(smx_simcall_t simcall, smx_process_t self){
568   return SIMIX_process_get_PPID(self);
569 }
570
571 int SIMIX_process_get_PPID(smx_process_t self){
572   if (self == NULL)
573     return 0;
574   else
575     return self->ppid;
576 }
577
578 void* SIMIX_pre_process_self_get_data(smx_simcall_t simcall, smx_process_t self){
579   return SIMIX_process_self_get_data(self);     
580 }
581
582 void* SIMIX_process_self_get_data(smx_process_t self)
583 {
584   xbt_assert(self == SIMIX_process_self(), "This is not the current process");
585
586   if (!self) {
587     return NULL;
588   }
589   return SIMIX_process_get_data(self);
590 }
591
592 void SIMIX_pre_process_set_data(smx_simcall_t simcall, smx_process_t process,
593                                 void *data){
594   SIMIX_process_set_data(process, data);
595 }
596 void SIMIX_process_self_set_data(smx_process_t self, void *data)
597 {
598   xbt_assert(self == SIMIX_process_self(), "This is not the current process");
599
600   SIMIX_process_set_data(self, data);
601 }
602
603 void* SIMIX_pre_process_get_data(smx_simcall_t simcall, smx_process_t process){
604   return SIMIX_process_get_data(process);
605 }
606 void* SIMIX_process_get_data(smx_process_t process)
607 {
608   return process->data;
609 }
610
611 void SIMIX_process_set_data(smx_process_t process, void *data)
612 {
613   process->data = data;
614 }
615
616 smx_host_t SIMIX_pre_process_get_host(smx_simcall_t simcall, smx_process_t process){
617   return SIMIX_process_get_host(process);
618 }
619 smx_host_t SIMIX_process_get_host(smx_process_t process)
620 {
621   return process->smx_host;
622 }
623
624 /* needs to be public and without simcall because it is called
625    by exceptions and logging events */
626 const char* SIMIX_process_self_get_name(void) {
627
628   smx_process_t process = SIMIX_process_self();
629   if (process == NULL || process == simix_global->maestro_process)
630     return "";
631
632   return SIMIX_process_get_name(process);
633 }
634
635 const char* SIMIX_pre_process_get_name(smx_simcall_t simcall, smx_process_t process) {
636   return SIMIX_process_get_name(process);
637 }
638 const char* SIMIX_process_get_name(smx_process_t process)
639 {
640   return process->name;
641 }
642
643 smx_process_t SIMIX_process_get_by_name(const char* name)
644 {
645   smx_process_t proc;
646
647   xbt_swag_foreach(proc, simix_global->process_list)
648   {
649     if(!strcmp(name, proc->name))
650       return proc;
651   }
652   return NULL;
653 }
654
655 int SIMIX_pre_process_is_suspended(smx_simcall_t simcall, smx_process_t process){
656   return SIMIX_process_is_suspended(process);
657 }
658 int SIMIX_process_is_suspended(smx_process_t process)
659 {
660   return process->suspended;
661 }
662
663 xbt_dict_t SIMIX_pre_process_get_properties(smx_simcall_t simcall, smx_process_t process){
664   return SIMIX_process_get_properties(process);
665 }
666 xbt_dict_t SIMIX_process_get_properties(smx_process_t process)
667 {
668   return process->properties;
669 }
670
671 void SIMIX_pre_process_sleep(smx_simcall_t simcall, double duration)
672 {
673   if (MC_is_active()) {
674     MC_process_clock_add(simcall->issuer, duration);
675     simcall_process_sleep__set__result(simcall, SIMIX_DONE);
676     SIMIX_simcall_answer(simcall);
677     return;
678   }
679   smx_action_t action = SIMIX_process_sleep(simcall->issuer, duration);
680   xbt_fifo_push(action->simcalls, simcall);
681   simcall->issuer->waiting_action = action;
682 }
683
684 smx_action_t SIMIX_process_sleep(smx_process_t process, double duration)
685 {
686   smx_action_t action;
687   smx_host_t host = process->smx_host;
688
689   /* check if the host is active */
690   if (surf_workstation_model->extension.
691       workstation.get_state(host) != SURF_RESOURCE_ON) {
692     THROWF(host_error, 0, "Host %s failed, you cannot call this function",
693            sg_host_name(host));
694   }
695
696   action = xbt_mallocator_get(simix_global->action_mallocator);
697   action->type = SIMIX_ACTION_SLEEP;
698   action->name = NULL;
699 #ifdef HAVE_TRACING
700   action->category = NULL;
701 #endif
702
703   action->sleep.host = host;
704   action->sleep.surf_sleep =
705       surf_workstation_model->extension.workstation.sleep(host, duration);
706
707   surf_workstation_model->action_data_set(action->sleep.surf_sleep, action);
708   XBT_DEBUG("Create sleep action %p", action);
709
710   return action;
711 }
712
713 void SIMIX_post_process_sleep(smx_action_t action)
714 {
715   smx_simcall_t simcall;
716   e_smx_state_t state;
717
718   while ((simcall = xbt_fifo_shift(action->simcalls))) {
719
720     switch(surf_workstation_model->action_state_get(action->sleep.surf_sleep)){
721       case SURF_ACTION_FAILED:
722         simcall->issuer->context->iwannadie = 1;
723         //SMX_EXCEPTION(simcall->issuer, host_error, 0, "Host failed");
724         break;
725
726       case SURF_ACTION_DONE:
727         state = SIMIX_DONE;
728         break;
729
730       default:
731         THROW_IMPOSSIBLE;
732         break;
733     }
734     if (surf_workstation_model->extension.
735         workstation.get_state(simcall->issuer->smx_host) != SURF_RESOURCE_ON) {
736       simcall->issuer->context->iwannadie = 1;
737     }
738     simcall_process_sleep__set__result(simcall, state);
739     simcall->issuer->waiting_action = NULL;
740     SIMIX_simcall_answer(simcall);
741
742   }
743   SIMIX_process_sleep_destroy(action);
744 }
745
746 void SIMIX_process_sleep_destroy(smx_action_t action)
747 {
748   XBT_DEBUG("Destroy action %p", action);
749   if (action->sleep.surf_sleep)
750     action->sleep.surf_sleep->model_type->action_unref(action->sleep.surf_sleep);
751   xbt_mallocator_release(simix_global->action_mallocator, action);
752 }
753
754 void SIMIX_process_sleep_suspend(smx_action_t action)
755 {
756   surf_workstation_model->suspend(action->sleep.surf_sleep);
757 }
758
759 void SIMIX_process_sleep_resume(smx_action_t action)
760 {
761   surf_workstation_model->resume(action->sleep.surf_sleep);
762 }
763
764 /** 
765  * \brief Calling this function makes the process to yield.
766  *
767  * Only the current process can call this function, giving back the control to
768  * maestro.
769  *
770  * \param self the current process
771  */
772 void SIMIX_process_yield(smx_process_t self)
773 {
774   XBT_DEBUG("Yield process '%s'", self->name);
775
776   /* Go into sleep and return control to maestro */
777   SIMIX_context_suspend(self->context);
778
779   /* Ok, maestro returned control to us */
780   XBT_DEBUG("Control returned to me: '%s'", self->name);
781
782   if (self->new_host) {
783     SIMIX_process_change_host(self, self->new_host);
784     self->new_host = NULL;
785   }
786
787   if (self->context->iwannadie){
788     XBT_DEBUG("I wanna die!");
789     SIMIX_process_stop(self);
790   }
791
792   if(self->suspended) {
793     xbt_assert(!self->doexception, "Gloups! This exception may be lost by subsequent calls.");
794     self->suspended = 0;
795     SIMIX_process_suspend(self,self);
796   }
797
798   if (self->doexception) {
799     XBT_DEBUG("Wait, maestro left me an exception");
800     self->doexception = 0;
801     SMX_THROW();
802   }
803
804 }
805
806 /* callback: context fetching */
807 xbt_running_ctx_t *SIMIX_process_get_running_context(void)
808 {
809   return SIMIX_process_self()->running_ctx;
810 }
811
812 /* callback: termination */
813 void SIMIX_process_exception_terminate(xbt_ex_t * e)
814 {
815   xbt_ex_display(e);
816   xbt_abort();
817 }
818
819 smx_context_t SIMIX_process_get_context(smx_process_t p) {
820   return p->context;
821 }
822
823 void SIMIX_process_set_context(smx_process_t p,smx_context_t c) {
824   p->context = c;
825 }
826
827 /**
828  * \brief Returns the list of processes to run.
829  */
830 xbt_dynar_t SIMIX_process_get_runnable(void)
831 {
832   return simix_global->process_to_run;
833 }
834
835 /**
836  * \brief Returns the process from PID.
837  */
838 smx_process_t SIMIX_process_from_PID(int PID)
839 {
840   smx_process_t proc;
841   xbt_swag_foreach(proc, simix_global->process_list)
842   {
843    if(proc->pid == PID)
844    return proc;
845   }
846   return NULL;
847 }
848
849 /** @brief returns a dynar containg all currently existing processes */
850 xbt_dynar_t SIMIX_processes_as_dynar(void) {
851   smx_process_t proc;
852   xbt_dynar_t res = xbt_dynar_new(sizeof(smx_process_t),NULL);
853   xbt_swag_foreach(proc, simix_global->process_list) {
854     xbt_dynar_push(res,&proc);
855   }
856   return res;
857 }
858
859
860 void SIMIX_process_on_exit_runall(smx_process_t process) {
861   s_smx_process_exit_fun_t exit_fun;
862
863   while (!xbt_dynar_is_empty(process->on_exit)) {
864     exit_fun = xbt_dynar_pop_as(process->on_exit,s_smx_process_exit_fun_t);
865     (exit_fun.fun)(exit_fun.arg);
866   }
867 }
868
869 void SIMIX_pre_process_on_exit(smx_simcall_t simcall, smx_process_t process,
870                                int_f_pvoid_t fun, void *data) {
871   SIMIX_process_on_exit(process, fun, data);
872 }
873
874 void SIMIX_process_on_exit(smx_process_t process, int_f_pvoid_t fun, void *data) {
875   xbt_assert(process, "current process not found: are you in maestro context ?");
876
877   if (!process->on_exit) {
878     process->on_exit = xbt_dynar_new(sizeof(s_smx_process_exit_fun_t), NULL);
879   }
880
881   s_smx_process_exit_fun_t exit_fun = {fun, data};
882
883   xbt_dynar_push_as(process->on_exit,s_smx_process_exit_fun_t,exit_fun);
884 }
885
886 void SIMIX_pre_process_auto_restart_set(smx_simcall_t simcall, smx_process_t process,
887                                         int auto_restart) {
888   SIMIX_process_auto_restart_set(process, auto_restart);        
889 }
890 /**
891  * \brief Sets the auto-restart status of the process.
892  * If set to 1, the process will be automatically restarted when its host
893  * comes back.
894  */
895 void SIMIX_process_auto_restart_set(smx_process_t process, int auto_restart) {
896   process->auto_restart = auto_restart;
897 }
898
899 smx_process_t SIMIX_pre_process_restart(smx_simcall_t simcall, smx_process_t process) {
900   return SIMIX_process_restart(process, simcall->issuer);       
901 }
902 /**
903  * \brief Restart a process.
904  * Restart a process, starting it again from the beginning.
905  */
906 smx_process_t SIMIX_process_restart(smx_process_t process, smx_process_t issuer) {
907   XBT_DEBUG("Restarting process %s on %s", process->name, sg_host_name(process->smx_host));
908   //retrieve the arguments of the old process
909   //FIXME: Factorise this with SIMIX_host_add_auto_restart_process ?
910   s_smx_process_arg_t arg;
911   arg.code = process->code;
912   arg.hostname = sg_host_name(process->smx_host);
913   arg.kill_time = process->kill_time;
914   arg.argc = process->argc;
915   arg.data = process->data;
916   int i;
917   arg.argv = xbt_new(char*,process->argc + 1);
918   for (i = 0; i < arg.argc; i++) {
919     arg.argv[i] = xbt_strdup(process->argv[i]);
920   }
921   arg.argv[process->argc] = NULL;
922   arg.properties = NULL;
923   arg.auto_restart = process->auto_restart;
924   //kill the old process
925   SIMIX_process_kill(process,issuer);
926   //start the new process
927   smx_process_t new_process;
928   if (simix_global->create_process_function) {
929     simix_global->create_process_function(&new_process,
930                                           arg.argv[0],
931                                           arg.code,
932                                           arg.data,
933                                           arg.hostname,
934                                           arg.kill_time,
935                                           arg.argc,
936                                           arg.argv,
937                                           arg.properties,
938                                           arg.auto_restart);
939   }
940   else {
941     simcall_process_create(&new_process,
942                                           arg.argv[0],
943                                           arg.code,
944                                           arg.data,
945                                           arg.hostname,
946                                           arg.kill_time,
947                                           arg.argc,
948                                           arg.argv,
949                                           arg.properties,
950                                           arg.auto_restart);
951
952   }
953   return new_process;
954 }