1 /* Copyright (c) 2007-2018. The SimGrid Team. All rights reserved. */
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. */
7 #include "simgrid/s4u/Engine.hpp"
8 #include "simgrid/s4u/Host.hpp"
10 #include "../kernel/activity/IoImpl.hpp"
11 #include "simgrid/sg_config.hpp"
12 #include "src/kernel/activity/SleepImpl.hpp"
13 #include "src/kernel/activity/SynchroRaw.hpp"
14 #include "src/mc/mc_record.hpp"
15 #include "src/mc/mc_replay.hpp"
16 #include "src/simix/smx_host_private.hpp"
17 #include "src/simix/smx_private.hpp"
18 #include "src/smpi/include/smpi_process.hpp"
19 #include "src/surf/StorageImpl.hpp"
20 #include "src/surf/xml/platf.hpp"
23 #include "src/mc/mc_private.hpp"
24 #include "src/mc/remote/Client.hpp"
25 #include "src/mc/remote/mc_protocol.h"
29 #include "src/smpi/include/private.hpp"
32 #include <boost/heap/fibonacci_heap.hpp>
35 XBT_LOG_NEW_CATEGORY(simix, "All SIMIX categories");
36 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(simix_kernel, simix, "Logging specific to SIMIX (kernel)");
38 std::unique_ptr<simgrid::simix::Global> simix_global;
41 typedef std::pair<double, smx_timer_t> TimerQelt;
42 boost::heap::fibonacci_heap<TimerQelt, boost::heap::compare<simgrid::xbt::HeapComparator<TimerQelt>>> simix_timers;
45 /** @brief Timer datatype */
50 decltype(simix_timers)::handle_type handle_;
51 simgrid::xbt::Task<void()> callback;
52 double getDate() { return date; }
53 s_smx_timer_t(double date, simgrid::xbt::Task<void()> callback) : date(date), callback(std::move(callback)) {}
56 void (*SMPI_switch_data_segment)(simgrid::s4u::ActorPtr) = nullptr;
58 bool _sg_do_verbose_exit = true;
59 static void inthandler(int)
61 if ( _sg_do_verbose_exit ) {
62 XBT_INFO("CTRL-C pressed. The current status will be displayed before exit (disable that behavior with option 'verbose-exit').");
63 SIMIX_display_process_status();
66 XBT_INFO("CTRL-C pressed, exiting. Hiding the current process status since 'verbose-exit' is set to false.");
72 static void segvhandler(int signum, siginfo_t* siginfo, void* /*context*/)
74 if (siginfo->si_signo == SIGSEGV && siginfo->si_code == SEGV_ACCERR) {
75 fprintf(stderr, "Access violation detected.\n"
76 "This probably comes from a programming error in your code, or from a stack\n"
77 "overflow. If you are certain of your code, try increasing the stack size\n"
78 " --cfg=contexts/stack-size=XXX (current size is %u KiB).\n"
80 "If it does not help, this may have one of the following causes:\n"
81 "a bug in SimGrid, a bug in the OS or a bug in a third-party libraries.\n"
82 "Failing hardware can sometimes generate such errors too.\n"
84 "If you think you've found a bug in SimGrid, please report it along with a\n"
85 "Minimal Working Example (MWE) reproducing your problem and a full backtrace\n"
86 "of the fault captured with gdb or valgrind.\n",
87 smx_context_stack_size / 1024);
88 } else if (siginfo->si_signo == SIGSEGV) {
89 fprintf(stderr, "Segmentation fault.\n");
91 if (smpi_enabled() && smpi_privatize_global_variables == SmpiPrivStrategies::NONE) {
92 #if HAVE_PRIVATIZATION
93 fprintf(stderr, "Try to enable SMPI variable privatization with --cfg=smpi/privatization:yes.\n");
95 fprintf(stderr, "Sadly, your system does not support --cfg=smpi/privatization:yes (yet).\n");
96 #endif /* HAVE_PRIVATIZATION */
98 #endif /* HAVE_SMPI */
103 char sigsegv_stack[SIGSTKSZ]; /* alternate stack for SIGSEGV handler */
106 * Install signal handler for SIGSEGV. Check that nobody has already installed
107 * its own handler. For example, the Java VM does this.
109 static void install_segvhandler()
113 stack.ss_sp = sigsegv_stack;
114 stack.ss_size = sizeof sigsegv_stack;
117 if (sigaltstack(&stack, &old_stack) == -1) {
118 XBT_WARN("Failed to register alternate signal stack: %s", strerror(errno));
121 if (not(old_stack.ss_flags & SS_DISABLE)) {
122 XBT_DEBUG("An alternate stack was already installed (sp=%p, size=%zu, flags=%x). Restore it.", old_stack.ss_sp,
123 old_stack.ss_size, (unsigned)old_stack.ss_flags);
124 sigaltstack(&old_stack, nullptr);
127 struct sigaction action;
128 struct sigaction old_action;
129 action.sa_sigaction = &segvhandler;
130 action.sa_flags = SA_ONSTACK | SA_RESETHAND | SA_SIGINFO;
131 sigemptyset(&action.sa_mask);
133 if (sigaction(SIGSEGV, &action, &old_action) == -1) {
134 XBT_WARN("Failed to register signal handler for SIGSEGV: %s", strerror(errno));
137 if ((old_action.sa_flags & SA_SIGINFO) || old_action.sa_handler != SIG_DFL) {
138 XBT_DEBUG("A signal handler was already installed for SIGSEGV (%p). Restore it.",
139 (old_action.sa_flags & SA_SIGINFO) ? (void*)old_action.sa_sigaction : (void*)old_action.sa_handler);
140 sigaction(SIGSEGV, &old_action, nullptr);
146 /********************************* SIMIX **************************************/
147 double SIMIX_timer_next()
149 return simix_timers.empty() ? -1.0 : simix_timers.top().first;
152 static void kill_process(smx_actor_t process)
154 SIMIX_process_kill(process, nullptr);
161 simgrid::config::Flag<double> breakpoint{"simix/breakpoint",
162 "When non-negative, raise a SIGTRAP after given (simulated) time", -1.0};
166 static simgrid::simix::ActorCode maestro_code;
167 void SIMIX_set_maestro(void (*code)(void*), void* data)
170 XBT_INFO("WARNING, SIMIX_set_maestro is believed to not work on windows. Please help us investigating this issue if you need that feature");
172 maestro_code = std::bind(code, data);
177 * \brief Initialize SIMIX internal data.
179 void SIMIX_global_init(int *argc, char **argv)
182 // The communication initialization is done ASAP.
183 // We need to communicate initialization of the different layers to the model-checker.
184 simgrid::mc::Client::initialize();
187 if (not simix_global) {
188 simix_global = std::unique_ptr<simgrid::simix::Global>(new simgrid::simix::Global());
189 simix_global->maestro_process = nullptr;
190 simix_global->create_process_function = &SIMIX_process_create;
191 simix_global->kill_process_function = &kill_process;
192 simix_global->cleanup_process_function = &SIMIX_process_cleanup;
193 simix_global->mutex = xbt_os_mutex_init();
195 surf_init(argc, argv); /* Initialize SURF structures */
196 SIMIX_context_mod_init();
198 // Either create a new context with maestro or create
199 // a context object with the current context mestro):
200 simgrid::kernel::actor::create_maestro(maestro_code);
202 /* Prepare to display some more info when dying on Ctrl-C pressing */
203 std::signal(SIGINT, inthandler);
206 install_segvhandler();
208 /* register a function to be called by SURF after the environment creation */
210 simgrid::s4u::on_platform_created.connect(SIMIX_post_create_environment);
212 simgrid::s4u::Storage::on_creation.connect([](simgrid::s4u::Storage& storage) {
213 sg_storage_t s = simgrid::s4u::Storage::by_name(storage.get_cname());
214 xbt_assert(s != nullptr, "Storage not found for name %s", storage.get_cname());
218 if (simgrid::config::get_value<bool>("clean-atexit"))
221 if (_sg_cfg_exit_asap)
228 * \brief Clean the SIMIX simulation
230 * This functions remove the memory used by SIMIX
235 return; // to avoid double cleaning by java and C
238 XBT_DEBUG("SIMIX_clean called. Simulation's over.");
239 if (not simix_global->process_to_run.empty() && SIMIX_get_clock() <= 0.0) {
241 XBT_CRITICAL("The time is still 0, and you still have processes ready to run.");
242 XBT_CRITICAL("It seems that you forgot to run the simulation that you setup.");
243 xbt_die("Bailing out to avoid that stop-before-start madness. Please fix your code.");
247 if (SIMIX_process_count()>0){
248 if(smpi_process()->initialized()){
249 xbt_die("Process exited without calling MPI_Finalize - Killing simulation");
251 XBT_WARN("Process called exit when leaving - Skipping cleanups");
257 /* Kill all processes (but maestro) */
258 SIMIX_process_killall(simix_global->maestro_process);
259 SIMIX_context_runall();
260 SIMIX_process_empty_trash();
262 /* Exit the SIMIX network module */
263 SIMIX_mailbox_exit();
265 while (not simix_timers.empty()) {
266 delete simix_timers.top().second;
269 /* Free the remaining data structures */
270 simix_global->process_to_run.clear();
271 simix_global->process_that_ran.clear();
272 simix_global->process_to_destroy.clear();
273 simix_global->process_list.clear();
275 xbt_os_mutex_destroy(simix_global->mutex);
276 simix_global->mutex = nullptr;
278 xbt_dynar_free(&simix_global->actors_vector);
279 xbt_dynar_free(&simix_global->dead_actors_vector);
282 /* Let's free maestro now */
283 delete simix_global->maestro_process->context_;
284 simix_global->maestro_process->context_ = nullptr;
285 delete simix_global->maestro_process;
286 simix_global->maestro_process = nullptr;
288 /* Finish context module and SURF */
289 SIMIX_context_mod_exit();
293 simix_global = nullptr;
299 * \brief A clock (in second).
301 * \return Return the clock.
303 double SIMIX_get_clock()
305 if(MC_is_active() || MC_record_replay_is_active()){
306 return MC_process_clock_get(SIMIX_process_self());
308 return surf_get_clock();
312 /** Wake up all processes waiting for a Surf action to finish */
313 static void SIMIX_wake_processes()
315 for (auto const& model : *all_existing_models) {
316 simgrid::kernel::resource::Action* action;
318 XBT_DEBUG("Handling the processes whose action failed (if any)");
319 while ((action = surf_model_extract_failed_action_set(model))) {
320 XBT_DEBUG(" Handling Action %p",action);
321 SIMIX_simcall_exit(static_cast<simgrid::kernel::activity::ActivityImpl*>(action->get_data()));
323 XBT_DEBUG("Handling the processes whose action terminated normally (if any)");
324 while ((action = surf_model_extract_done_action_set(model))) {
325 XBT_DEBUG(" Handling Action %p",action);
326 if (action->get_data() == nullptr)
327 XBT_DEBUG("probably vcpu's action %p, skip", action);
329 SIMIX_simcall_exit(static_cast<simgrid::kernel::activity::ActivityImpl*>(action->get_data()));
334 /** Handle any pending timer */
335 static bool SIMIX_execute_timers()
338 while (not simix_timers.empty() && SIMIX_get_clock() >= simix_timers.top().first) {
340 // FIXME: make the timers being real callbacks
341 // (i.e. provide dispatchers that read and expand the args)
342 smx_timer_t timer = simix_timers.top().second;
347 xbt_die("Exception thrown ouf of timer callback");
354 /** Execute all the tasks that are queued
356 * e.g. `.then()` callbacks of futures.
358 static bool SIMIX_execute_tasks()
360 xbt_assert(simix_global->tasksTemp.empty());
362 if (simix_global->tasks.empty())
367 // We don't want the callbacks to modify the vector we are iterating over:
368 swap(simix_global->tasks, simix_global->tasksTemp);
370 // Execute all the queued tasks:
371 for (auto& task : simix_global->tasksTemp)
374 simix_global->tasksTemp.clear();
375 } while (not simix_global->tasks.empty());
382 * \brief Run the main simulation loop.
386 if (not MC_record_path.empty()) {
387 simgrid::mc::replay(MC_record_path);
394 XBT_DEBUG("New Schedule Round; size(queue)=%zu", simix_global->process_to_run.size());
396 if (simgrid::simix::breakpoint >= 0.0 && surf_get_clock() >= simgrid::simix::breakpoint) {
397 XBT_DEBUG("Breakpoint reached (%g)", simgrid::simix::breakpoint.get());
398 simgrid::simix::breakpoint = -1.0;
406 SIMIX_execute_tasks();
408 while (not simix_global->process_to_run.empty()) {
409 XBT_DEBUG("New Sub-Schedule Round; size(queue)=%zu", simix_global->process_to_run.size());
411 /* Run all processes that are ready to run, possibly in parallel */
412 SIMIX_process_runall();
414 /* answer sequentially and in a fixed arbitrary order all the simcalls that were issued during that sub-round */
416 /* WARNING, the order *must* be fixed or you'll jeopardize the simulation reproducibility (see RR-7653) */
418 /* Here, the order is ok because:
420 * Short proof: only maestro adds stuff to the process_to_run array, so the execution order of user contexts do
421 * not impact its order.
423 * Long proof: processes remain sorted through an arbitrary (implicit, complex but fixed) order in all cases.
425 * - if there is no kill during the simulation, processes remain sorted according by their PID.
426 * Rationale: This can be proved inductively.
427 * Assume that process_to_run is sorted at a beginning of one round (it is at round 0: the deployment file
428 * is parsed linearly).
429 * Let's show that it is still so at the end of this round.
430 * - if a process is added when being created, that's from maestro. It can be either at startup
431 * time (and then in PID order), or in response to a process_create simcall. Since simcalls are handled
432 * in arbitrary order (inductive hypothesis), we are fine.
433 * - If a process is added because it's getting killed, its subsequent actions shouldn't matter
434 * - If a process gets added to process_to_run because one of their blocking action constituting the meat
435 * of a simcall terminates, we're still good. Proof:
436 * - You are added from SIMIX_simcall_answer() only. When this function is called depends on the resource
437 * kind (network, cpu, disk, whatever), but the same arguments hold. Let's take communications as an
439 * - For communications, this function is called from SIMIX_comm_finish().
440 * This function itself don't mess with the order since simcalls are handled in FIFO order.
441 * The function is called:
442 * - before the comm starts (invalid parameters, or resource already dead or whatever).
443 * The order then trivial holds since maestro didn't interrupt its handling of the simcall yet
444 * - because the communication failed or were canceled after startup. In this case, it's called from
445 * the function we are in, by the chunk:
446 * set = model->states.failed_action_set;
447 * while ((synchro = extract(set)))
448 * SIMIX_simcall_post((smx_synchro_t) synchro->data);
449 * This order is also fixed because it depends of the order in which the surf actions were
450 * added to the system, and only maestro can add stuff this way, through simcalls.
451 * We thus use the inductive hypothesis once again to conclude that the order in which synchros are
452 * poped out of the set does not depend on the user code's execution order.
453 * - because the communication terminated. In this case, synchros are served in the order given by
454 * set = model->states.done_action_set;
455 * while ((synchro = extract(set)))
456 * SIMIX_simcall_post((smx_synchro_t) synchro->data);
457 * and the argument is very similar to the previous one.
458 * So, in any case, the orders of calls to SIMIX_comm_finish() do not depend on the order in which user
459 * processes are executed.
460 * So, in any cases, the orders of processes within process_to_run do not depend on the order in which
461 * user processes were executed previously.
462 * So, if there is no killing in the simulation, the simulation reproducibility is not jeopardized.
463 * - If there is some process killings, the order is changed by this decision that comes from user-land
464 * But this decision may not have been motivated by a situation that were different because the simulation is
466 * So, even the order change induced by the process killing is perfectly reproducible.
468 * So science works, bitches [http://xkcd.com/54/].
470 * We could sort the process_that_ran array completely so that we can describe the order in which simcalls are
471 * handled (like "according to the PID of issuer"), but it's not mandatory (order is fixed already even if
473 * That would thus be a pure waste of time.
476 for (smx_actor_t const& process : simix_global->process_that_ran) {
477 if (process->simcall.call != SIMCALL_NONE) {
478 SIMIX_simcall_handle(&process->simcall, 0);
482 SIMIX_execute_tasks();
484 SIMIX_wake_processes();
485 } while (SIMIX_execute_tasks());
487 /* If only daemon processes remain, cancel their actions, mark them to die and reschedule them */
488 if (simix_global->process_list.size() == simix_global->daemons.size())
489 for (auto const& dmon : simix_global->daemons) {
490 XBT_DEBUG("Kill %s", dmon->get_cname());
491 SIMIX_process_kill(dmon, simix_global->maestro_process);
495 time = SIMIX_timer_next();
496 if (time > -1.0 || not simix_global->process_list.empty()) {
497 XBT_DEBUG("Calling surf_solve");
498 time = surf_solve(time);
499 XBT_DEBUG("Moving time ahead : %g", time);
502 /* Notify all the hosts that have failed */
503 /* FIXME: iterate through the list of failed host and mark each of them */
504 /* as failed. On each host, signal all the running processes with host_fail */
506 // Execute timers and tasks until there isn't anything to be done:
509 again = SIMIX_execute_timers();
510 if (SIMIX_execute_tasks())
512 SIMIX_wake_processes();
515 /* Autorestart all process */
516 for (auto const& host : host_that_restart) {
517 XBT_INFO("Restart processes on host %s", host->get_cname());
518 SIMIX_host_autorestart(host);
520 host_that_restart.clear();
522 /* Clean processes to destroy */
523 SIMIX_process_empty_trash();
525 XBT_DEBUG("### time %f, #processes %zu, #to_run %zu", time, simix_global->process_list.size(),
526 simix_global->process_to_run.size());
528 } while (time > -1.0 || not simix_global->process_to_run.empty());
530 if (not simix_global->process_list.empty()) {
532 if (simix_global->process_list.size() <= simix_global->daemons.size()) {
533 XBT_CRITICAL("Oops! Daemon actors cannot do any blocking activity (communications, synchronization, etc) "
534 "once the simulation is over. Please fix your on_exit() functions.");
536 XBT_CRITICAL("Oops! Deadlock or code not perfectly clean.");
538 SIMIX_display_process_status();
539 simgrid::s4u::on_deadlock();
542 simgrid::s4u::on_simulation_end();
546 * \brief Set the date to execute a function
548 * Set the date to execute the function on the surf.
549 * \param date Date to execute function
550 * \param callback Function to be executed
551 * \param arg Parameters of the function
554 smx_timer_t SIMIX_timer_set(double date, void (*callback)(void*), void *arg)
556 smx_timer_t timer = new s_smx_timer_t(date, simgrid::xbt::make_task([callback, arg]() { callback(arg); }));
557 timer->handle_ = simix_timers.emplace(std::make_pair(date, timer));
561 smx_timer_t SIMIX_timer_set(double date, simgrid::xbt::Task<void()> callback)
563 smx_timer_t timer = new s_smx_timer_t(date, std::move(callback));
564 timer->handle_ = simix_timers.emplace(std::make_pair(date, timer));
568 /** @brief cancels a timer that was added earlier */
569 void SIMIX_timer_remove(smx_timer_t timer) {
570 simix_timers.erase(timer->handle_);
574 /** @brief Returns the date at which the timer will trigger (or 0 if nullptr timer) */
575 double SIMIX_timer_get_date(smx_timer_t timer) {
576 return timer ? timer->getDate() : 0;
580 * \brief Registers a function to create a process.
582 * This function registers a function to be called
583 * when a new process is created. The function has
584 * to call SIMIX_process_create().
585 * \param function create process function
587 void SIMIX_function_register_process_create(smx_creation_func_t function)
589 simix_global->create_process_function = function;
593 * \brief Registers a function to kill a process.
595 * This function registers a function to be called when a process is killed. The function has to call the
596 * SIMIX_process_kill().
598 * \param function Kill process function
600 void SIMIX_function_register_process_kill(void_pfn_smxprocess_t function)
602 simix_global->kill_process_function = function;
606 * \brief Registers a function to cleanup a process.
608 * This function registers a user function to be called when a process ends properly.
610 * \param function cleanup process function
612 void SIMIX_function_register_process_cleanup(void_pfn_smxprocess_t function)
614 simix_global->cleanup_process_function = function;
618 void SIMIX_display_process_status()
620 int nbprocess = simix_global->process_list.size();
622 XBT_INFO("%d processes are still running, waiting for something.", nbprocess);
623 /* List the process and their state */
624 XBT_INFO("Legend of the following listing: \"Process <pid> (<name>@<host>): <status>\"");
625 for (auto const& kv : simix_global->process_list) {
626 smx_actor_t process = kv.second;
628 if (process->waiting_synchro) {
630 const char* synchro_description = "unknown";
632 if (boost::dynamic_pointer_cast<simgrid::kernel::activity::ExecImpl>(process->waiting_synchro) != nullptr)
633 synchro_description = "execution";
635 if (boost::dynamic_pointer_cast<simgrid::kernel::activity::CommImpl>(process->waiting_synchro) != nullptr)
636 synchro_description = "communication";
638 if (boost::dynamic_pointer_cast<simgrid::kernel::activity::SleepImpl>(process->waiting_synchro) != nullptr)
639 synchro_description = "sleeping";
641 if (boost::dynamic_pointer_cast<simgrid::kernel::activity::RawImpl>(process->waiting_synchro) != nullptr)
642 synchro_description = "synchronization";
644 if (boost::dynamic_pointer_cast<simgrid::kernel::activity::IoImpl>(process->waiting_synchro) != nullptr)
645 synchro_description = "I/O";
647 XBT_INFO("Process %ld (%s@%s): waiting for %s synchro %p (%s) in state %d to finish", process->pid_,
648 process->get_cname(), process->host_->get_cname(), synchro_description, process->waiting_synchro.get(),
649 process->waiting_synchro->name_.c_str(), (int)process->waiting_synchro->state_);
652 XBT_INFO("Process %ld (%s@%s)", process->pid_, process->get_cname(), process->host_->get_cname());
657 int SIMIX_is_maestro()
659 smx_actor_t self = SIMIX_process_self();
660 return simix_global == nullptr /*SimDag*/ || self == nullptr || self == simix_global->maestro_process;