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Let the model-checker decide if the wait transitions should timeout or not.
[simgrid.git] / 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 (rdv->name)
55       xbt_dict_set(rdv_points, rdv->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, int idx)
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     if(idx == 0){
330       action->state = SIMIX_DONE;
331     }else{
332       /* If we reached this point, the wait request must have a timeout */
333       /* Otherwise it shouldn't be enabled and executed by the MC */
334       if(timeout == -1)
335         THROW_IMPOSSIBLE;
336
337       if(action->comm.src_proc == req->issuer)
338         action->state = SIMIX_SRC_TIMEOUT;
339       else
340         action->state = SIMIX_DST_TIMEOUT;
341     }
342
343     SIMIX_comm_finish(action);
344     return;
345   }
346
347   /* If the action has already finish perform the error handling, */
348   /* otherwise set up a waiting timeout on the right side         */
349   if (action->state != SIMIX_WAITING && action->state != SIMIX_RUNNING) {
350     SIMIX_comm_finish(action);
351   } 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 */
352     sleep = surf_workstation_model->extension.workstation.sleep(req->issuer->smx_host->host, timeout);
353     surf_workstation_model->action_data_set(sleep, action);
354
355     if (req->issuer == action->comm.src_proc)
356       action->comm.src_timeout = sleep;
357     else
358       action->comm.dst_timeout = sleep;
359   }
360 }
361
362 void SIMIX_pre_comm_test(smx_req_t req)
363 {
364   smx_action_t action = req->comm_test.comm;
365   req->comm_test.result = (action->state != SIMIX_WAITING && action->state != SIMIX_RUNNING);
366
367   if (req->comm_test.result) {
368     xbt_fifo_push(action->request_list, req);
369     SIMIX_comm_finish(action);
370   } else {
371     SIMIX_request_answer(req);
372   }
373 }
374
375 void SIMIX_pre_comm_testany(smx_req_t req, int idx)
376 {
377   unsigned int cursor;
378   smx_action_t action;
379   xbt_dynar_t actions = req->comm_testany.comms;
380   req->comm_testany.result = -1;
381
382   if (MC_IS_ENABLED){
383     if(idx == -1){
384       SIMIX_request_answer(req);
385     }else{
386       action = xbt_dynar_get_as(actions, idx, smx_action_t);
387       xbt_fifo_push(action->request_list, req);
388       action->state = SIMIX_DONE;
389       SIMIX_comm_finish(action);
390     }
391     return;
392   }
393
394   xbt_dynar_foreach(req->comm_testany.comms,cursor,action) {
395     if (action->state != SIMIX_WAITING && action->state != SIMIX_RUNNING) {
396       req->comm_testany.result = cursor;
397       xbt_fifo_push(action->request_list, req);
398       SIMIX_comm_finish(action);
399       return;
400     }
401   }
402   SIMIX_request_answer(req);
403 }
404
405 void SIMIX_pre_comm_waitany(smx_req_t req, int idx)
406 {
407   smx_action_t action;
408   unsigned int cursor = 0;
409   xbt_dynar_t actions = req->comm_waitany.comms;
410
411   if (MC_IS_ENABLED){
412     action = xbt_dynar_get_as(actions, idx, smx_action_t);
413     xbt_fifo_push(action->request_list, req);
414     req->comm_waitany.result = idx;
415     action->state = SIMIX_DONE;
416     SIMIX_comm_finish(action);
417     return;
418   }
419
420   xbt_dynar_foreach(actions, cursor, action){
421     /* Associate this request to the action */
422     xbt_fifo_push(action->request_list, req);
423     if (action->state != SIMIX_WAITING && action->state != SIMIX_RUNNING){
424       SIMIX_comm_finish(action);
425       break;
426     }
427   }
428 }
429
430 void SIMIX_waitany_req_remove_from_actions(smx_req_t req)
431 {
432   smx_action_t action;
433   unsigned int cursor = 0;
434   xbt_dynar_t actions = req->comm_waitany.comms;
435
436   xbt_dynar_foreach(actions, cursor, action){
437     xbt_fifo_remove(action->request_list, req);
438   }
439 }
440
441 /**
442  *  \brief Start the simulation of a communication request
443  *  \param action The communication action
444  */
445 static XBT_INLINE void SIMIX_comm_start(smx_action_t action)
446 {
447   /* If both the sender and the receiver are already there, start the communication */
448   if (action->state == SIMIX_READY) {
449     smx_host_t sender = action->comm.src_proc->smx_host;
450     smx_host_t receiver = action->comm.dst_proc->smx_host;
451
452     DEBUG3("Starting communication %p from '%s' to '%s'", action,
453            SIMIX_host_get_name(sender), SIMIX_host_get_name(receiver));
454
455     action->comm.surf_comm = surf_workstation_model->extension.workstation.
456         communicate(sender->host, receiver->host, action->comm.task_size, action->comm.rate);
457
458     surf_workstation_model->action_data_set(action->comm.surf_comm, action);
459
460     action->state = SIMIX_RUNNING;
461
462 #ifdef HAVE_TRACING
463     TRACE_smx_action_communicate(action, action->comm.src_proc);
464 #endif
465
466     /* If a link is failed, detect it immediately */
467     if (surf_workstation_model->action_state_get(action->comm.surf_comm) == SURF_ACTION_FAILED) {
468       DEBUG2("Communication from '%s' to '%s' failed to start because of a link failure",
469           SIMIX_host_get_name(sender), SIMIX_host_get_name(receiver));
470       action->state = SIMIX_LINK_FAILURE;
471       SIMIX_comm_destroy_internal_actions(action);
472     }
473
474     /* If any of the process is suspend, create the action but stop its execution,
475        it will be restarted when the sender process resume */
476     if (SIMIX_process_is_suspended(action->comm.src_proc) ||
477         SIMIX_process_is_suspended(action->comm.dst_proc)) {
478       /* FIXME: check what should happen with the action state */
479       surf_workstation_model->suspend(action->comm.surf_comm);
480     }
481   }
482 }
483
484 void SIMIX_comm_finish(smx_action_t action)
485 {
486   smx_req_t req;
487
488   while ((req = xbt_fifo_shift(action->request_list))) {
489
490     /* If a waitany request is waiting for this action to finish, then remove
491        it from the other actions in the waitany list. Afterwards, get the
492        position of the actual action in the waitany request's actions dynar and
493        return it as the result of the call */
494     if (req->call == REQ_COMM_WAITANY) {
495       SIMIX_waitany_req_remove_from_actions(req);
496       if(!MC_IS_ENABLED)
497         req->comm_waitany.result = xbt_dynar_search(req->comm_waitany.comms, &action);
498     }
499
500     /* If the action is still in a rendez-vous point then remove from it */
501     if (action->comm.rdv)
502       SIMIX_rdv_remove(action->comm.rdv, action);
503
504     DEBUG1("SIMIX_comm_finish: action state = %d", action->state);
505
506     /* Check out for errors */
507     switch (action->state) {
508
509       case SIMIX_DONE:
510         DEBUG1("Communication %p complete!", action);
511         SIMIX_comm_copy_data(action);
512         break;
513
514       case SIMIX_SRC_TIMEOUT:
515         TRY {
516           THROW0(timeout_error, 0, "Communication timeouted because of sender");
517         }
518         CATCH(req->issuer->running_ctx->exception) {
519           req->issuer->doexception = 1;
520         }
521         break;
522
523       case SIMIX_DST_TIMEOUT:
524         TRY {
525           THROW0(timeout_error, 0, "Communication timeouted because of receiver");
526         }
527         CATCH(req->issuer->running_ctx->exception) {
528           req->issuer->doexception = 1;
529         }
530         break;
531
532       case SIMIX_SRC_HOST_FAILURE:
533         TRY {
534           if (req->issuer == action->comm.src_proc)
535             THROW0(host_error, 0, "Host failed");
536           else
537             THROW0(network_error, 0, "Remote peer failed");
538         }
539         CATCH(req->issuer->running_ctx->exception) {
540           req->issuer->doexception = 1;
541         }
542         break;
543
544       case SIMIX_DST_HOST_FAILURE:
545         TRY {
546           if (req->issuer == action->comm.dst_proc)
547             THROW0(host_error, 0, "Host failed");
548           else
549             THROW0(network_error, 0, "Remote peer failed");
550         }
551         CATCH(req->issuer->running_ctx->exception) {
552           req->issuer->doexception = 1;
553         }
554         break;
555
556       case SIMIX_LINK_FAILURE:
557         TRY {
558           DEBUG5("Link failure in action %p between '%s' and '%s': posting an exception to the issuer: %s (%p)",
559               action, action->comm.src_proc->smx_host->name, action->comm.dst_proc->smx_host->name,
560               req->issuer->name, req->issuer);
561           THROW0(network_error, 0, "Link failure");
562         }
563         CATCH(req->issuer->running_ctx->exception) {
564           req->issuer->doexception = 1;
565         }
566         break;
567
568       default:
569         THROW_IMPOSSIBLE;
570     }
571
572     /* if there is an exception during a waitany or a testany, indicate the position of the failed communication */
573     if (req->issuer->doexception) {
574       if (req->call == REQ_COMM_WAITANY) {
575         req->issuer->running_ctx->exception.value = xbt_dynar_search(req->comm_waitany.comms, &action);
576       }
577       else if (req->call == REQ_COMM_TESTANY) {
578         req->issuer->running_ctx->exception.value = xbt_dynar_search(req->comm_testany.comms, &action);
579       }
580     }
581
582     req->issuer->waiting_action = NULL;
583     SIMIX_request_answer(req);
584   }
585 }
586
587 void SIMIX_post_comm(smx_action_t action)
588 {
589   /* Update action state */
590   if (action->comm.src_timeout &&
591      surf_workstation_model->action_state_get(action->comm.src_timeout) == SURF_ACTION_DONE)
592      action->state = SIMIX_SRC_TIMEOUT;
593   else if (action->comm.dst_timeout &&
594           surf_workstation_model->action_state_get(action->comm.dst_timeout) == SURF_ACTION_DONE)
595      action->state = SIMIX_DST_TIMEOUT;
596   else if (action->comm.src_timeout &&
597           surf_workstation_model->action_state_get(action->comm.src_timeout) == SURF_ACTION_FAILED)
598      action->state = SIMIX_SRC_HOST_FAILURE;
599   else if (action->comm.dst_timeout &&
600           surf_workstation_model->action_state_get(action->comm.dst_timeout) == SURF_ACTION_FAILED)
601      action->state = SIMIX_DST_HOST_FAILURE;
602   else if (action->comm.surf_comm &&
603           surf_workstation_model->action_state_get(action->comm.surf_comm) == SURF_ACTION_FAILED)
604      action->state = SIMIX_LINK_FAILURE;
605   else
606     action->state = SIMIX_DONE;
607
608   DEBUG1("SIMIX_post_comm: action state = %d", action->state);
609
610   /* After this point the surf actions associated with the simix communicate
611      action are no longer needed, thus we delete them. */
612   SIMIX_comm_destroy_internal_actions(action);
613
614   /* If there are requests associated with the action, then answer them */
615   if (xbt_fifo_size(action->request_list))
616     SIMIX_comm_finish(action);
617 }
618
619 void SIMIX_comm_cancel(smx_action_t action)
620 {
621   /* If the action is a waiting state means that it is still in a rdv */
622   /* so remove from it and delete it */
623   if (action->state == SIMIX_WAITING) {
624     SIMIX_rdv_remove(action->comm.rdv, action);
625     action->state = SIMIX_FAILED;
626   } else {
627     /* When running the MC there are no surf actions */
628     if(!MC_IS_ENABLED)
629       surf_workstation_model->action_cancel(action->comm.surf_comm);
630   }
631 }
632
633 void SIMIX_comm_suspend(smx_action_t action)
634 {
635   /*FIXME: shall we suspend also the timeout actions? */
636   surf_workstation_model->suspend(action->comm.surf_comm);
637 }
638
639 void SIMIX_comm_resume(smx_action_t action)
640 {
641   /*FIXME: check what happen with the timeouts */
642   surf_workstation_model->resume(action->comm.surf_comm);
643 }
644
645
646 /************* Action Getters **************/
647
648 /**
649  *  \brief get the amount remaining from the communication
650  *  \param action The communication
651  */
652 double SIMIX_comm_get_remains(smx_action_t action)
653 {
654   double remains;
655
656   switch (action->state) {
657
658     case SIMIX_RUNNING:
659       remains = surf_workstation_model->get_remains(action->comm.surf_comm);
660       break;
661
662     case SIMIX_WAITING:
663     case SIMIX_READY:
664       remains = 0; /*FIXME: check what should be returned */
665       break;
666
667     default:
668       remains = 0; /*FIXME: is this correct? */
669       break;
670   }
671   return remains;
672 }
673
674 e_smx_state_t SIMIX_comm_get_state(smx_action_t action)
675 {
676   return action->state;
677 }
678
679 /**
680  *  \brief Return the user data associated to the sender of the communication
681  *  \param action The communication
682  *  \return the user data
683  */
684 void* SIMIX_comm_get_src_data(smx_action_t action)
685 {
686   return action->comm.src_data;
687 }
688
689 /**
690  *  \brief Return the user data associated to the receiver of the communication
691  *  \param action The communication
692  *  \return the user data
693  */
694 void* SIMIX_comm_get_dst_data(smx_action_t action)
695 {
696   return action->comm.dst_data;
697 }
698
699 void* SIMIX_comm_get_src_buff(smx_action_t action)
700 {
701   return action->comm.src_buff;
702 }
703
704 void* SIMIX_comm_get_dst_buff(smx_action_t action)
705 {
706   return action->comm.dst_buff;
707 }
708
709 size_t SIMIX_comm_get_src_buff_size(smx_action_t action)
710 {
711   return action->comm.src_buff_size;
712 }
713
714 size_t SIMIX_comm_get_dst_buff_size(smx_action_t action)
715 {
716   size_t buff_size;
717
718   if (action->comm.dst_buff_size)
719     buff_size = *(action->comm.dst_buff_size);
720   else
721     buff_size = 0;
722
723   return buff_size;
724 }
725
726 smx_process_t SIMIX_comm_get_src_proc(smx_action_t action)
727 {
728   return action->comm.src_proc;
729 }
730
731 smx_process_t SIMIX_comm_get_dst_proc(smx_action_t action)
732 {
733   return action->comm.dst_proc;
734 }
735
736 #ifdef HAVE_LATENCY_BOUND_TRACKING
737 /**
738  *  \brief verify if communication is latency bounded
739  *  \param comm The communication
740  */
741 XBT_INLINE int SIMIX_comm_is_latency_bounded(smx_action_t action)
742 {
743   if (action->comm.surf_comm){
744       DEBUG1("Getting latency limited for surf_action (%p)", action->comm.surf_comm);
745       action->latency_limited = surf_workstation_model->get_latency_limited(action->comm.surf_comm);
746       DEBUG1("Action limited is %d", action->latency_limited);
747   }
748   return action->latency_limited;
749 }
750 #endif
751
752 /******************************************************************************/
753 /*                    SIMIX_comm_copy_data callbacks                       */
754 /******************************************************************************/
755 static void (*SIMIX_comm_copy_data_callback) (smx_action_t, size_t) =
756     &SIMIX_comm_copy_pointer_callback;
757
758 void
759 SIMIX_comm_set_copy_data_callback(void (*callback) (smx_action_t, size_t))
760 {
761   SIMIX_comm_copy_data_callback = callback;
762 }
763
764 void SIMIX_comm_copy_pointer_callback(smx_action_t comm, size_t buff_size)
765 {
766   xbt_assert1((buff_size == sizeof(void *)),
767               "Cannot copy %zu bytes: must be sizeof(void*)", buff_size);
768   *(void **) (comm->comm.dst_buff) = comm->comm.src_buff;
769 }
770
771 void SIMIX_comm_copy_buffer_callback(smx_action_t comm, size_t buff_size)
772 {
773   memcpy(comm->comm.dst_buff, comm->comm.src_buff, buff_size);
774 }
775
776 /**
777  *  \brief Copy the communication data from the sender's buffer to the receiver's one
778  *  \param comm The communication
779  */
780 void SIMIX_comm_copy_data(smx_action_t comm)
781 {
782   size_t buff_size = comm->comm.src_buff_size;
783   /* If there is no data to be copy then return */
784   if (!comm->comm.src_buff || !comm->comm.dst_buff || comm->comm.copied == 1)
785     return;
786
787   DEBUG6("Copying comm %p data from %s (%p) -> %s (%p) (%zu bytes)",
788          comm,
789          comm->comm.src_proc->smx_host->name, comm->comm.src_buff,
790          comm->comm.dst_proc->smx_host->name, comm->comm.dst_buff, buff_size);
791
792   /* Copy at most dst_buff_size bytes of the message to receiver's buffer */
793   if (comm->comm.dst_buff_size)
794     buff_size = MIN(buff_size, *(comm->comm.dst_buff_size));
795
796   /* Update the receiver's buffer size to the copied amount */
797   if (comm->comm.dst_buff_size)
798     *comm->comm.dst_buff_size = buff_size;
799
800   if (buff_size == 0)
801     return;
802
803   (*SIMIX_comm_copy_data_callback) (comm, buff_size);
804
805   /* Set the copied flag so we copy data only once */
806   /* (this function might be called from both communication ends) */
807   comm->comm.copied = 1;
808 }