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When the host dies, the actor need an exception even if it's not blocked on an activity
[simgrid.git] / src / simix / ActorImpl.cpp
1 /* Copyright (c) 2007-2018. The SimGrid Team. All rights reserved.          */
2
3 /* This program is free software; you can redistribute it and/or modify it
4  * under the terms of the license (GNU LGPL) which comes with this package. */
5
6 #include "mc/mc.h"
7 #include "simgrid/Exception.hpp"
8 #include "smx_private.hpp"
9 #include "src/kernel/activity/CommImpl.hpp"
10 #include "src/kernel/activity/ExecImpl.hpp"
11 #include "src/kernel/activity/IoImpl.hpp"
12 #include "src/kernel/activity/SleepImpl.hpp"
13 #include "src/kernel/activity/SynchroRaw.hpp"
14 #include "src/mc/mc_replay.hpp"
15 #include "src/mc/remote/Client.hpp"
16 #include "src/simix/smx_host_private.hpp"
17 #include "src/simix/smx_io_private.hpp"
18 #include "src/simix/smx_synchro_private.hpp"
19 #include "src/surf/HostImpl.hpp"
20 #include "src/surf/cpu_interface.hpp"
21
22 #ifdef HAVE_SMPI
23 #include "src/smpi/include/private.hpp"
24 #endif
25
26 #include <boost/range/algorithm.hpp>
27
28 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(simix_process, simix, "Logging specific to SIMIX (process)");
29
30 unsigned long simix_process_maxpid = 0;
31
32 /**
33  * @brief Returns the current agent.
34  *
35  * This functions returns the currently running SIMIX process.
36  *
37  * @return The SIMIX process
38  */
39 smx_actor_t SIMIX_process_self()
40 {
41   smx_context_t self_context = SIMIX_context_self();
42
43   return (self_context != nullptr) ? self_context->process() : nullptr;
44 }
45
46 /**
47  * @brief Returns whether a process has pending asynchronous communications.
48  * @return true if there are asynchronous communications in this process
49  */
50 int SIMIX_process_has_pending_comms(smx_actor_t process) {
51
52   return process->comms.size() > 0;
53 }
54
55 /**
56  * @brief Moves a process to the list of processes to destroy.
57  */
58 void SIMIX_process_cleanup(smx_actor_t process)
59 {
60   XBT_DEBUG("Cleanup process %s (%p), waiting synchro %p", process->get_cname(), process,
61             process->waiting_synchro.get());
62
63   process->finished_ = true;
64   SIMIX_process_on_exit_runall(process);
65
66   /* Unregister from the kill timer if any */
67   if (process->kill_timer != nullptr) {
68     SIMIX_timer_remove(process->kill_timer);
69     process->kill_timer = nullptr;
70   }
71
72   simix_global->mutex.lock();
73
74   /* cancel non-blocking communications */
75   while (not process->comms.empty()) {
76     smx_activity_t synchro = process->comms.front();
77     process->comms.pop_front();
78     simgrid::kernel::activity::CommImplPtr comm =
79         boost::static_pointer_cast<simgrid::kernel::activity::CommImpl>(synchro);
80
81     /* make sure no one will finish the comm after this process is destroyed,
82      * because src_proc or dst_proc would be an invalid pointer */
83
84     if (comm->src_proc == process) {
85       XBT_DEBUG("Found an unfinished send comm %p (detached = %d), state %d, src = %p, dst = %p", comm.get(),
86                 comm->detached, (int)comm->state_, comm->src_proc, comm->dst_proc);
87       comm->src_proc = nullptr;
88
89     } else if (comm->dst_proc == process) {
90       XBT_DEBUG("Found an unfinished recv comm %p, state %d, src = %p, dst = %p", comm.get(), (int)comm->state_,
91                 comm->src_proc, comm->dst_proc);
92       comm->dst_proc = nullptr;
93
94       if (comm->detached && comm->src_proc != nullptr) {
95         /* the comm will be freed right now, remove it from the sender */
96         comm->src_proc->comms.remove(comm);
97       }
98     } else {
99       xbt_die("Communication synchro %p is in my list but I'm not the sender nor the receiver", synchro.get());
100     }
101     comm->cancel();
102   }
103
104   XBT_DEBUG("%p should not be run anymore",process);
105   simix_global->process_list.erase(process->pid_);
106   if (process->host_ && process->host_process_list_hook.is_linked())
107     simgrid::xbt::intrusive_erase(process->host_->pimpl_->process_list_, *process);
108   if (not process->smx_destroy_list_hook.is_linked()) {
109 #if SIMGRID_HAVE_MC
110     xbt_dynar_push_as(simix_global->dead_actors_vector, smx_actor_t, process);
111 #endif
112     simix_global->process_to_destroy.push_back(*process);
113   }
114   process->context_->iwannadie = false;
115
116   simix_global->mutex.unlock();
117 }
118
119 /**
120  * Garbage collection
121  *
122  * Should be called some time to time to free the memory allocated for processes that have finished (or killed).
123  */
124 void SIMIX_process_empty_trash()
125 {
126   while (not simix_global->process_to_destroy.empty()) {
127     smx_actor_t process = &simix_global->process_to_destroy.front();
128     simix_global->process_to_destroy.pop_front();
129     XBT_DEBUG("Getting rid of %p",process);
130     intrusive_ptr_release(process);
131   }
132 #if SIMGRID_HAVE_MC
133   xbt_dynar_reset(simix_global->dead_actors_vector);
134 #endif
135 }
136
137 namespace simgrid {
138
139 namespace kernel {
140 namespace actor {
141
142 ActorImpl::~ActorImpl()
143 {
144   delete this->context_;
145 }
146
147 static void dying_daemon(int /*exit_status*/, void* data)
148 {
149   std::vector<ActorImpl*>* vect = &simix_global->daemons;
150
151   auto it = std::find(vect->begin(), vect->end(), static_cast<ActorImpl*>(data));
152   xbt_assert(it != vect->end(), "The dying daemon is not a daemon after all. Please report that bug.");
153
154   /* Don't move the whole content since we don't really care about the order */
155   std::swap(*it, vect->back());
156   vect->pop_back();
157 }
158
159 /** This process will be terminated automatically when the last non-daemon process finishes */
160 void ActorImpl::daemonize()
161 {
162   if (not daemon_) {
163     daemon_ = true;
164     simix_global->daemons.push_back(this);
165     SIMIX_process_on_exit(this, dying_daemon, this);
166   }
167 }
168
169 simgrid::s4u::Actor* ActorImpl::restart()
170 {
171   XBT_DEBUG("Restarting process %s on %s", get_cname(), host_->get_cname());
172
173   // retrieve the arguments of the old process
174   simgrid::kernel::actor::ProcessArg arg = ProcessArg(host_, this);
175
176   // kill the old process
177   SIMIX_process_kill(this, (this == simix_global->maestro_process) ? this : SIMIX_process_self());
178
179   // start the new process
180   ActorImpl* actor = simix_global->create_process_function(arg.name.c_str(), std::move(arg.code), arg.data, arg.host,
181                                                            arg.properties.get(), nullptr);
182   simcall_process_set_kill_time(actor, arg.kill_time);
183   actor->set_auto_restart(arg.auto_restart);
184
185   return actor->ciface();
186 }
187
188 smx_activity_t ActorImpl::suspend(ActorImpl* issuer)
189 {
190   if (suspended_) {
191     XBT_DEBUG("Actor '%s' is already suspended", get_cname());
192     return nullptr;
193   }
194
195   suspended_ = true;
196
197   /* If we are suspending another actor that is waiting on a sync, suspend its synchronization. */
198   if (this != issuer) {
199     if (waiting_synchro)
200       waiting_synchro->suspend();
201     /* If the other actor is not waiting, its suspension is delayed to when the actor is rescheduled. */
202
203     return nullptr;
204   } else {
205     return SIMIX_execution_start("suspend", "", 0.0, 1.0, 0.0, this->host_);
206   }
207 }
208
209 void ActorImpl::resume()
210 {
211   XBT_IN("process = %p", this);
212
213   if (context_->iwannadie) {
214     XBT_VERB("Ignoring request to suspend an actor that is currently dying.");
215     return;
216   }
217
218   if (not suspended_)
219     return;
220   suspended_ = false;
221
222   /* resume the synchronization that was blocking the resumed actor. */
223   if (waiting_synchro)
224     waiting_synchro->resume();
225
226   XBT_OUT();
227 }
228
229 smx_activity_t ActorImpl::sleep(double duration)
230 {
231   if (host_->is_off())
232     throw_exception(std::make_exception_ptr(simgrid::HostFailureException(
233         XBT_THROW_POINT, std::string("Host ") + std::string(host_->get_cname()) + " failed, you cannot sleep there.")));
234
235   simgrid::kernel::activity::SleepImpl* synchro = new simgrid::kernel::activity::SleepImpl();
236   synchro->host                                 = host_;
237   synchro->surf_sleep                           = host_->pimpl_cpu->sleep(duration);
238   synchro->surf_sleep->set_data(synchro);
239   XBT_DEBUG("Create sleep synchronization %p", synchro);
240
241   return synchro;
242 }
243
244 void ActorImpl::throw_exception(std::exception_ptr e)
245 {
246   exception = e;
247
248   if (suspended_)
249     resume();
250
251   /* cancel the blocking synchro if any */
252   if (waiting_synchro) {
253
254     simgrid::kernel::activity::ExecImplPtr exec =
255         boost::dynamic_pointer_cast<simgrid::kernel::activity::ExecImpl>(waiting_synchro);
256     if (exec != nullptr && exec->surf_action_)
257       exec->surf_action_->cancel();
258
259     simgrid::kernel::activity::CommImplPtr comm =
260         boost::dynamic_pointer_cast<simgrid::kernel::activity::CommImpl>(waiting_synchro);
261     if (comm != nullptr) {
262       comms.remove(comm);
263       comm->cancel();
264     }
265
266     simgrid::kernel::activity::SleepImplPtr sleep =
267         boost::dynamic_pointer_cast<simgrid::kernel::activity::SleepImpl>(waiting_synchro);
268     if (sleep != nullptr) {
269       SIMIX_process_sleep_destroy(waiting_synchro);
270       if (std::find(begin(simix_global->process_to_run), end(simix_global->process_to_run), this) ==
271               end(simix_global->process_to_run) &&
272           this != SIMIX_process_self()) {
273         XBT_DEBUG("Inserting %s in the to_run list", get_cname());
274         simix_global->process_to_run.push_back(this);
275       }
276     }
277
278     simgrid::kernel::activity::RawImplPtr raw =
279         boost::dynamic_pointer_cast<simgrid::kernel::activity::RawImpl>(waiting_synchro);
280     if (raw != nullptr) {
281       SIMIX_synchro_stop_waiting(this, &simcall);
282     }
283
284     simgrid::kernel::activity::IoImplPtr io =
285         boost::dynamic_pointer_cast<simgrid::kernel::activity::IoImpl>(waiting_synchro);
286     if (io != nullptr) {
287       delete io.get();
288     }
289   }
290   waiting_synchro = nullptr;
291 }
292
293 void create_maestro(simgrid::simix::ActorCode code)
294 {
295   smx_actor_t maestro = nullptr;
296   /* Create maestro process and initialize it */
297   maestro           = new simgrid::kernel::actor::ActorImpl();
298   maestro->pid_     = simix_process_maxpid++;
299   maestro->name_    = "";
300   maestro->set_user_data(nullptr);
301
302   if (not code) {
303     maestro->context_ = SIMIX_context_new(simgrid::simix::ActorCode(), nullptr, maestro);
304   } else {
305     if (not simix_global)
306       xbt_die("simix is not initialized, please call MSG_init first");
307     maestro->context_ = simix_global->context_factory->create_maestro(code, maestro);
308   }
309
310   maestro->simcall.issuer = maestro;
311   simix_global->maestro_process = maestro;
312 }
313
314 } // namespace actor
315 }
316 }
317
318 /** @brief Creates and runs the maestro process */
319 void SIMIX_maestro_create(void (*code)(void*), void* data)
320 {
321   simgrid::kernel::actor::create_maestro(std::bind(code, data));
322 }
323
324 /**
325  * @brief Internal function to create a process.
326  *
327  * This function actually creates the process.
328  * It may be called when a SIMCALL_PROCESS_CREATE simcall occurs,
329  * or directly for SIMIX internal purposes. The sure thing is that it's called from maestro context.
330  *
331  * @return the process created
332  */
333 smx_actor_t SIMIX_process_create(std::string name, simgrid::simix::ActorCode code, void* data, simgrid::s4u::Host* host,
334                                  std::unordered_map<std::string, std::string>* properties, smx_actor_t parent_process)
335 {
336
337   XBT_DEBUG("Start process %s on host '%s'", name.c_str(), host->get_cname());
338
339   if (host->is_off()) {
340     XBT_WARN("Cannot launch process '%s' on failed host '%s'", name.c_str(), host->get_cname());
341     return nullptr;
342   }
343
344   smx_actor_t process = new simgrid::kernel::actor::ActorImpl();
345
346   xbt_assert(code && host != nullptr, "Invalid parameters");
347   /* Process data */
348   process->pid_           = simix_process_maxpid++;
349   process->name_          = simgrid::xbt::string(name);
350   process->host_          = host;
351   process->set_user_data(data);
352   process->simcall.issuer = process;
353
354   if (parent_process != nullptr) {
355     process->ppid_ = parent_process->pid_;
356   }
357
358   process->code         = code;
359
360   XBT_VERB("Create context %s", process->get_cname());
361   process->context_ = SIMIX_context_new(std::move(code), simix_global->cleanup_process_function, process);
362
363   /* Add properties */
364   if (properties != nullptr)
365     for (auto const& kv : *properties)
366       process->set_property(kv.first, kv.second);
367
368   /* Add the process to its host's process list */
369   host->pimpl_->process_list_.push_back(*process);
370
371   XBT_DEBUG("Start context '%s'", process->get_cname());
372
373   /* Now insert it in the global process list and in the process to run list */
374   simix_global->process_list[process->pid_] = process;
375   XBT_DEBUG("Inserting %s(%s) in the to_run list", process->get_cname(), host->get_cname());
376   simix_global->process_to_run.push_back(process);
377   intrusive_ptr_add_ref(process);
378
379   /* The onCreation() signal must be delayed until there, where the pid and everything is set */
380   simgrid::s4u::ActorPtr tmp = process->iface(); // Passing this directly to onCreation will lead to crashes
381   simgrid::s4u::Actor::on_creation(tmp);
382
383   return process;
384 }
385
386 smx_actor_t SIMIX_process_attach(const char* name, void* data, const char* hostname,
387                                  std::unordered_map<std::string, std::string>* properties, smx_actor_t parent_process)
388 {
389   // This is mostly a copy/paste from SIMIX_process_new(),
390   // it'd be nice to share some code between those two functions.
391
392   sg_host_t host = sg_host_by_name(hostname);
393   XBT_DEBUG("Attach process %s on host '%s'", name, hostname);
394
395   if (host->is_off()) {
396     XBT_WARN("Cannot launch process '%s' on failed host '%s'", name, hostname);
397     return nullptr;
398   }
399
400   smx_actor_t process = new simgrid::kernel::actor::ActorImpl();
401   /* Process data */
402   process->pid_  = simix_process_maxpid++;
403   process->name_ = std::string(name);
404   process->host_ = host;
405   process->set_user_data(data);
406   process->simcall.issuer = process;
407
408   if (parent_process != nullptr) {
409     process->ppid_ = parent_process->pid_;
410   }
411
412   /* Process data for auto-restart */
413   process->code = nullptr;
414
415   XBT_VERB("Create context %s", process->get_cname());
416   if (not simix_global)
417     xbt_die("simix is not initialized, please call MSG_init first");
418   process->context_ = simix_global->context_factory->attach(simix_global->cleanup_process_function, process);
419
420   /* Add properties */
421   if (properties != nullptr)
422     for (auto const& kv : *properties)
423       process->set_property(kv.first, kv.second);
424
425   /* Add the process to it's host process list */
426   host->pimpl_->process_list_.push_back(*process);
427
428   /* Now insert it in the global process list and in the process to run list */
429   simix_global->process_list[process->pid_] = process;
430   XBT_DEBUG("Inserting %s(%s) in the to_run list", process->get_cname(), host->get_cname());
431   simix_global->process_to_run.push_back(process);
432   intrusive_ptr_add_ref(process);
433
434   auto* context = dynamic_cast<simgrid::kernel::context::AttachContext*>(process->context_);
435   if (not context)
436     xbt_die("Not a suitable context");
437
438   context->attach_start();
439
440   /* The onCreation() signal must be delayed until there, where the pid and everything is set */
441   simgrid::s4u::ActorPtr tmp = process->iface(); // Passing this directly to onCreation will lead to crashes
442   simgrid::s4u::Actor::on_creation(tmp);
443
444   return process;
445 }
446
447 void SIMIX_process_detach()
448 {
449   auto* context = dynamic_cast<simgrid::kernel::context::AttachContext*>(SIMIX_context_self());
450   if (not context)
451     xbt_die("Not a suitable context");
452
453   auto process = context->process();
454   simix_global->cleanup_process_function(process);
455   context->attach_stop();
456 }
457
458 /**
459  * @brief Executes the processes from simix_global->process_to_run.
460  *
461  * The processes of simix_global->process_to_run are run (in parallel if
462  * possible).  On exit, simix_global->process_to_run is empty, and
463  * simix_global->process_that_ran contains the list of processes that just ran.
464  * The two lists are swapped so, be careful when using them before and after a
465  * call to this function.
466  */
467 void SIMIX_process_runall()
468 {
469   SIMIX_context_runall();
470
471   simix_global->process_to_run.swap(simix_global->process_that_ran);
472   simix_global->process_to_run.clear();
473 }
474
475 /**
476  * @brief Internal function to kill a SIMIX process.
477  *
478  * This function may be called when a SIMCALL_PROCESS_KILL simcall occurs,
479  * or directly for SIMIX internal purposes.
480  *
481  * @param process poor victim
482  * @param issuer the process which has sent the PROCESS_KILL. Important to not schedule twice the same process.
483  */
484 void SIMIX_process_kill(smx_actor_t process, smx_actor_t issuer) {
485
486   if (process->finished_) {
487     XBT_DEBUG("Ignoring request to kill process %s@%s that is already dead", process->get_cname(),
488               process->host_->get_cname());
489     return;
490   }
491
492   XBT_DEBUG("Actor '%s'@%s is killing actor '%s'@%s", issuer->get_cname(),
493             (issuer->host_ == nullptr ? "(null)" : issuer->host_->get_cname()), process->get_cname(),
494             process->host_->get_cname());
495
496   process->context_->iwannadie = true;
497   process->blocked_            = false;
498   process->suspended_          = false;
499   process->exception = nullptr;
500
501   if (process->host_->is_off())
502     process->throw_exception(std::make_exception_ptr(simgrid::HostFailureException(XBT_THROW_POINT, "Host failed")));
503
504   /* destroy the blocking synchro if any */
505   if (process->waiting_synchro != nullptr) {
506
507     simgrid::kernel::activity::ExecImplPtr exec =
508         boost::dynamic_pointer_cast<simgrid::kernel::activity::ExecImpl>(process->waiting_synchro);
509     simgrid::kernel::activity::CommImplPtr comm =
510         boost::dynamic_pointer_cast<simgrid::kernel::activity::CommImpl>(process->waiting_synchro);
511     simgrid::kernel::activity::SleepImplPtr sleep =
512         boost::dynamic_pointer_cast<simgrid::kernel::activity::SleepImpl>(process->waiting_synchro);
513     simgrid::kernel::activity::RawImplPtr raw =
514         boost::dynamic_pointer_cast<simgrid::kernel::activity::RawImpl>(process->waiting_synchro);
515     simgrid::kernel::activity::IoImplPtr io =
516         boost::dynamic_pointer_cast<simgrid::kernel::activity::IoImpl>(process->waiting_synchro);
517
518     if (exec != nullptr) {
519       if (exec->surf_action_) {
520         exec->surf_action_->cancel();
521         exec->surf_action_->unref();
522         exec->surf_action_ = nullptr;
523       }
524     } else if (comm != nullptr) {
525       process->comms.remove(process->waiting_synchro);
526       comm->cancel();
527       // Remove first occurrence of &process->simcall:
528       auto i = boost::range::find(process->waiting_synchro->simcalls_, &process->simcall);
529       if (i != process->waiting_synchro->simcalls_.end())
530         process->waiting_synchro->simcalls_.remove(&process->simcall);
531     } else if (sleep != nullptr) {
532       if (sleep->surf_sleep)
533         sleep->surf_sleep->cancel();
534       sleep->post();
535     } else if (raw != nullptr) {
536       SIMIX_synchro_stop_waiting(process, &process->simcall);
537
538     } else if (io != nullptr) {
539       delete io.get();
540     } else {
541       simgrid::kernel::activity::ActivityImplPtr activity = process->waiting_synchro;
542       xbt_die("Activity %s is of unknown type %s", activity->name_.c_str(),
543               simgrid::xbt::demangle(typeid(activity).name()).get());
544     }
545
546     process->waiting_synchro = nullptr;
547   }
548   if (std::find(begin(simix_global->process_to_run), end(simix_global->process_to_run), process) ==
549           end(simix_global->process_to_run) &&
550       process != issuer) {
551     XBT_DEBUG("Inserting %s in the to_run list", process->get_cname());
552     simix_global->process_to_run.push_back(process);
553   }
554 }
555
556 /** @deprecated When this function gets removed, also remove the xbt_ex class, that is only there to help users to
557  * transition */
558 void SIMIX_process_throw(smx_actor_t process, xbt_errcat_t cat, int value, const char *msg) {
559   SMX_EXCEPTION(process, cat, value, msg);
560
561   if (process->suspended_)
562     process->resume();
563
564   /* cancel the blocking synchro if any */
565   if (process->waiting_synchro) {
566
567     simgrid::kernel::activity::ExecImplPtr exec =
568         boost::dynamic_pointer_cast<simgrid::kernel::activity::ExecImpl>(process->waiting_synchro);
569     if (exec != nullptr && exec->surf_action_)
570       exec->surf_action_->cancel();
571
572     simgrid::kernel::activity::CommImplPtr comm =
573         boost::dynamic_pointer_cast<simgrid::kernel::activity::CommImpl>(process->waiting_synchro);
574     if (comm != nullptr) {
575       process->comms.remove(comm);
576       comm->cancel();
577     }
578
579     simgrid::kernel::activity::SleepImplPtr sleep =
580         boost::dynamic_pointer_cast<simgrid::kernel::activity::SleepImpl>(process->waiting_synchro);
581     if (sleep != nullptr) {
582       SIMIX_process_sleep_destroy(process->waiting_synchro);
583       if (std::find(begin(simix_global->process_to_run), end(simix_global->process_to_run), process) ==
584               end(simix_global->process_to_run) &&
585           process != SIMIX_process_self()) {
586         XBT_DEBUG("Inserting %s in the to_run list", process->get_cname());
587         simix_global->process_to_run.push_back(process);
588       }
589     }
590
591     simgrid::kernel::activity::RawImplPtr raw =
592         boost::dynamic_pointer_cast<simgrid::kernel::activity::RawImpl>(process->waiting_synchro);
593     if (raw != nullptr) {
594       SIMIX_synchro_stop_waiting(process, &process->simcall);
595     }
596
597     simgrid::kernel::activity::IoImplPtr io =
598         boost::dynamic_pointer_cast<simgrid::kernel::activity::IoImpl>(process->waiting_synchro);
599     if (io != nullptr) {
600       delete io.get();
601     }
602   }
603   process->waiting_synchro = nullptr;
604
605 }
606
607 /**
608  * @brief Kills all running processes.
609  * @param issuer this one will not be killed
610  */
611 void SIMIX_process_killall(smx_actor_t issuer)
612 {
613   for (auto const& kv : simix_global->process_list)
614     if (kv.second != issuer)
615       SIMIX_process_kill(kv.second, issuer);
616 }
617
618 void SIMIX_process_change_host(smx_actor_t actor, sg_host_t dest)
619 {
620   xbt_assert((actor != nullptr), "Invalid parameters");
621   simgrid::xbt::intrusive_erase(actor->host_->pimpl_->process_list_, *actor);
622   actor->host_ = dest;
623   dest->pimpl_->process_list_.push_back(*actor);
624 }
625
626 void simcall_HANDLER_process_suspend(smx_simcall_t simcall, smx_actor_t process)
627 {
628   smx_activity_t sync_suspend = process->suspend(simcall->issuer);
629
630   if (process != simcall->issuer) {
631     SIMIX_simcall_answer(simcall);
632   } else {
633     sync_suspend->simcalls_.push_back(simcall);
634     process->waiting_synchro = sync_suspend;
635     process->waiting_synchro->suspend();
636   }
637   /* If we are suspending ourselves, then just do not finish the simcall now */
638 }
639
640 int SIMIX_process_get_maxpid() {
641   return simix_process_maxpid;
642 }
643
644 int SIMIX_process_count()
645 {
646   return simix_global->process_list.size();
647 }
648
649 void* SIMIX_process_self_get_data()
650 {
651   smx_actor_t self = SIMIX_process_self();
652
653   if (not self) {
654     return nullptr;
655   }
656   return self->get_user_data();
657 }
658
659 void SIMIX_process_self_set_data(void *data)
660 {
661   SIMIX_process_self()->set_user_data(data);
662 }
663
664
665 /* needs to be public and without simcall because it is called
666    by exceptions and logging events */
667 const char* SIMIX_process_self_get_name() {
668
669   smx_actor_t process = SIMIX_process_self();
670   if (process == nullptr || process == simix_global->maestro_process)
671     return "maestro";
672
673   return process->get_cname();
674 }
675
676 void simcall_HANDLER_process_join(smx_simcall_t simcall, smx_actor_t process, double timeout)
677 {
678   if (process->finished_) {
679     // The joined process is already finished, just wake up the issuer process right away
680     simcall_process_sleep__set__result(simcall, SIMIX_DONE);
681     SIMIX_simcall_answer(simcall);
682     return;
683   }
684   smx_activity_t sync = SIMIX_process_join(simcall->issuer, process, timeout);
685   sync->simcalls_.push_back(simcall);
686   simcall->issuer->waiting_synchro = sync;
687 }
688
689 smx_activity_t SIMIX_process_join(smx_actor_t issuer, smx_actor_t process, double timeout)
690 {
691   smx_activity_t res = issuer->sleep(timeout);
692   intrusive_ptr_add_ref(res.get());
693   SIMIX_process_on_exit(process,
694                         [](int, void* arg) {
695                           auto sleep = static_cast<simgrid::kernel::activity::SleepImpl*>(arg);
696                           if (sleep->surf_sleep)
697                             sleep->surf_sleep->finish(simgrid::kernel::resource::Action::State::FINISHED);
698                           intrusive_ptr_release(sleep);
699                         },
700                         res.get());
701   return res;
702 }
703
704 void simcall_HANDLER_process_sleep(smx_simcall_t simcall, double duration)
705 {
706   if (MC_is_active() || MC_record_replay_is_active()) {
707     MC_process_clock_add(simcall->issuer, duration);
708     simcall_process_sleep__set__result(simcall, SIMIX_DONE);
709     SIMIX_simcall_answer(simcall);
710     return;
711   }
712   smx_activity_t sync = simcall->issuer->sleep(duration);
713   sync->simcalls_.push_back(simcall);
714   simcall->issuer->waiting_synchro = sync;
715 }
716
717 void SIMIX_process_sleep_destroy(smx_activity_t synchro)
718 {
719   XBT_DEBUG("Destroy sleep synchro %p", synchro.get());
720   simgrid::kernel::activity::SleepImplPtr sleep =
721       boost::dynamic_pointer_cast<simgrid::kernel::activity::SleepImpl>(synchro);
722
723   if (sleep->surf_sleep) {
724     sleep->surf_sleep->unref();
725     sleep->surf_sleep = nullptr;
726   }
727 }
728
729 /**
730  * @brief Calling this function makes the process to yield.
731  *
732  * Only the current process can call this function, giving back the control to maestro.
733  *
734  * @param self the current process
735  */
736 void SIMIX_process_yield(smx_actor_t self)
737 {
738   XBT_DEBUG("Yield actor '%s'", self->get_cname());
739
740   /* Go into sleep and return control to maestro */
741   self->context_->suspend();
742
743   /* Ok, maestro returned control to us */
744   XBT_DEBUG("Control returned to me: '%s'", self->get_cname());
745
746   if (self->context_->iwannadie) {
747     XBT_DEBUG("I wanna die!");
748     self->finished_ = true;
749     /* execute the on_exit functions */
750     SIMIX_process_on_exit_runall(self);
751
752     if (self->auto_restart_ && self->host_->is_off() &&
753         watched_hosts.find(self->host_->get_cname()) == watched_hosts.end()) {
754       XBT_DEBUG("Push host %s to watched_hosts because it's off and %s needs to restart", self->host_->get_cname(),
755                 self->get_cname());
756       watched_hosts.insert(self->host_->get_cname());
757     }
758
759     XBT_DEBUG("Process %s@%s is dead", self->get_cname(), self->host_->get_cname());
760     self->context_->stop();
761   }
762
763   if (self->suspended_) {
764     XBT_DEBUG("Hey! I'm suspended.");
765     xbt_assert(self->exception != nullptr, "Gasp! This exception may be lost by subsequent calls.");
766     self->suspended_ = false;
767     self->suspend(self);
768   }
769
770   if (self->exception != nullptr) {
771     XBT_DEBUG("Wait, maestro left me an exception");
772     std::exception_ptr exception = std::move(self->exception);
773     self->exception = nullptr;
774     std::rethrow_exception(std::move(exception));
775   }
776
777   if (SMPI_switch_data_segment && not self->finished_) {
778     SMPI_switch_data_segment(self->iface());
779   }
780 }
781
782 /** @brief Returns the list of processes to run. */
783 const std::vector<smx_actor_t>& simgrid::simix::process_get_runnable()
784 {
785   return simix_global->process_to_run;
786 }
787
788 /** @brief Returns the process from PID. */
789 smx_actor_t SIMIX_process_from_PID(aid_t PID)
790 {
791   auto process = simix_global->process_list.find(PID);
792   return process == simix_global->process_list.end() ? nullptr : process->second;
793 }
794
795 void SIMIX_process_on_exit_runall(smx_actor_t process) {
796   simgrid::s4u::Actor::on_destruction(process->iface());
797   smx_process_exit_status_t exit_status = (process->context_->iwannadie) ? SMX_EXIT_FAILURE : SMX_EXIT_SUCCESS;
798   while (not process->on_exit.empty()) {
799     s_smx_process_exit_fun_t exit_fun = process->on_exit.back();
800     process->on_exit.pop_back();
801     (exit_fun.fun)(exit_status, exit_fun.arg);
802   }
803 }
804
805 void SIMIX_process_on_exit(smx_actor_t process, int_f_pvoid_pvoid_t fun, void* data)
806 {
807   SIMIX_process_on_exit(process, [fun](int a, void* b) { fun((void*)(intptr_t)a, b); }, data);
808 }
809
810 void SIMIX_process_on_exit(smx_actor_t process, std::function<void(int, void*)> fun, void* data)
811 {
812   xbt_assert(process, "current process not found: are you in maestro context ?");
813
814   process->on_exit.emplace_back(s_smx_process_exit_fun_t{fun, data});
815 }
816
817 /** @brief Restart a process, starting it again from the beginning. */
818 /**
819  * @ingroup simix_process_management
820  * @brief Creates and runs a new SIMIX process.
821  *
822  * The structure and the corresponding thread are created and put in the list of ready processes.
823  *
824  * @param name a name for the process. It is for user-level information and can be nullptr.
825  * @param code the main function of the process
826  * @param data a pointer to any data one may want to attach to the new object. It is for user-level information and can
827  * be nullptr.
828  * It can be retrieved with the method ActorImpl::getUserData().
829  * @param host where the new agent is executed.
830  * @param argc first argument passed to @a code
831  * @param argv second argument passed to @a code
832  * @param properties the properties of the process
833  */
834 smx_actor_t simcall_process_create(std::string name, xbt_main_func_t code, void* data, sg_host_t host, int argc,
835                                    char** argv, std::unordered_map<std::string, std::string>* properties)
836 {
837   auto wrapped_code = simgrid::xbt::wrap_main(code, argc, argv);
838   for (int i = 0; i != argc; ++i)
839     xbt_free(argv[i]);
840   xbt_free(argv);
841   smx_actor_t res = simcall_process_create(name, std::move(wrapped_code), data, host, properties);
842   return res;
843 }
844
845 smx_actor_t simcall_process_create(std::string name, simgrid::simix::ActorCode code, void* data, sg_host_t host,
846                                    std::unordered_map<std::string, std::string>* properties)
847 {
848   smx_actor_t self = SIMIX_process_self();
849   return simgrid::simix::simcall([name, code, data, host, properties, self] {
850     return SIMIX_process_create(name, std::move(code), data, host, properties, self);
851   });
852 }