1 /* Copyright (c) 2011-2019. 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. */
11 #include <boost/range/algorithm.hpp>
16 #include <xbt/automaton.h>
17 #include <xbt/dynar.h>
19 #include <xbt/sysdep.h>
21 #include "src/mc/Session.hpp"
22 #include "src/mc/Transition.hpp"
23 #include "src/mc/checker/LivenessChecker.hpp"
24 #include "src/mc/mc_exit.hpp"
25 #include "src/mc/mc_private.hpp"
26 #include "src/mc/mc_private.hpp"
27 #include "src/mc/mc_record.hpp"
28 #include "src/mc/mc_replay.hpp"
29 #include "src/mc/mc_request.hpp"
30 #include "src/mc/mc_smx.hpp"
31 #include "src/mc/remote/Client.hpp"
33 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_liveness, mc, "Logging specific to algorithms for liveness properties verification");
35 /********* Static functions *********/
40 VisitedPair::VisitedPair(int pair_num, xbt_automaton_state_t automaton_state,
41 std::shared_ptr<const std::vector<int>> atomic_propositions,
42 std::shared_ptr<simgrid::mc::State> graph_state)
43 : num(pair_num), automaton_state(automaton_state)
45 simgrid::mc::RemoteClient* process = &(mc_model_checker->process());
47 this->graph_state = std::move(graph_state);
48 if(this->graph_state->system_state == nullptr)
49 this->graph_state->system_state = simgrid::mc::take_snapshot(pair_num);
50 this->heap_bytes_used = mmalloc_get_bytes_used_remote(process->get_heap()->heaplimit, process->get_malloc_info());
52 this->actors_count = mc_model_checker->process().actors().size();
55 this->atomic_propositions = std::move(atomic_propositions);
58 static bool evaluate_label(xbt_automaton_exp_label_t l, std::vector<int> const& values)
61 case xbt_automaton_exp_label::AUT_OR:
62 return evaluate_label(l->u.or_and.left_exp, values)
63 || evaluate_label(l->u.or_and.right_exp, values);
64 case xbt_automaton_exp_label::AUT_AND:
65 return evaluate_label(l->u.or_and.left_exp, values)
66 && evaluate_label(l->u.or_and.right_exp, values);
67 case xbt_automaton_exp_label::AUT_NOT:
68 return not evaluate_label(l->u.exp_not, values);
69 case xbt_automaton_exp_label::AUT_PREDICAT:{
70 unsigned int cursor = 0;
71 xbt_automaton_propositional_symbol_t p = nullptr;
72 xbt_dynar_foreach(simgrid::mc::property_automaton->propositional_symbols, cursor, p) {
73 if (std::strcmp(xbt_automaton_propositional_symbol_get_name(p), l->u.predicat) == 0)
74 return values[cursor] != 0;
76 xbt_die("Missing predicate");
79 case xbt_automaton_exp_label::AUT_ONE:
82 xbt_die("Unexpected vaue for automaton");
86 Pair::Pair(unsigned long expanded_pairs) : num(expanded_pairs)
89 std::shared_ptr<const std::vector<int>> LivenessChecker::getPropositionValues()
91 std::vector<int> values;
92 unsigned int cursor = 0;
93 xbt_automaton_propositional_symbol_t ps = nullptr;
94 xbt_dynar_foreach(simgrid::mc::property_automaton->propositional_symbols, cursor, ps)
95 values.push_back(xbt_automaton_propositional_symbol_evaluate(ps));
96 return std::make_shared<const std::vector<int>>(std::move(values));
99 int LivenessChecker::compare(simgrid::mc::VisitedPair* state1, simgrid::mc::VisitedPair* state2)
101 simgrid::mc::Snapshot* s1 = state1->graph_state->system_state.get();
102 simgrid::mc::Snapshot* s2 = state2->graph_state->system_state.get();
103 int num1 = state1->num;
104 int num2 = state2->num;
105 return simgrid::mc::snapshot_compare(num1, s1, num2, s2);
108 std::shared_ptr<VisitedPair> LivenessChecker::insertAcceptancePair(simgrid::mc::Pair* pair)
110 std::shared_ptr<VisitedPair> new_pair = std::make_shared<VisitedPair>(
111 pair->num, pair->automaton_state, pair->atomic_propositions,
114 auto res = boost::range::equal_range(acceptancePairs_, new_pair.get(),
115 simgrid::mc::DerefAndCompareByActorsCountAndUsedHeap());
117 if (pair->search_cycle) for (auto i = res.first; i != res.second; ++i) {
118 std::shared_ptr<simgrid::mc::VisitedPair> const& pair_test = *i;
119 if (xbt_automaton_state_compare(
120 pair_test->automaton_state, new_pair->automaton_state) != 0
121 || *(pair_test->atomic_propositions) != *(new_pair->atomic_propositions)
122 || this->compare(pair_test.get(), new_pair.get()) != 0)
124 XBT_INFO("Pair %d already reached (equal to pair %d) !", new_pair->num, pair_test->num);
125 explorationStack_.pop_back();
126 if (dot_output != nullptr)
127 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", this->previousPair_, pair_test->num,
128 this->previousRequest_.c_str());
132 acceptancePairs_.insert(res.first, new_pair);
136 void LivenessChecker::removeAcceptancePair(int pair_num)
138 for (auto i = acceptancePairs_.begin(); i != acceptancePairs_.end(); ++i)
139 if ((*i)->num == pair_num) {
140 acceptancePairs_.erase(i);
145 void LivenessChecker::replay()
147 XBT_DEBUG("**** Begin Replay ****");
149 /* Intermediate backtracking */
150 if(_sg_mc_checkpoint > 0) {
151 simgrid::mc::Pair* pair = explorationStack_.back().get();
152 if(pair->graph_state->system_state){
153 simgrid::mc::restore_snapshot(pair->graph_state->system_state);
158 /* Restore the initial state */
159 simgrid::mc::session->restoreInitialState();
161 /* Traverse the stack from the initial state and re-execute the transitions */
163 for (std::shared_ptr<Pair> const& pair : explorationStack_) {
164 if (pair == explorationStack_.back())
167 std::shared_ptr<State> state = pair->graph_state;
169 if (pair->exploration_started) {
171 int req_num = state->transition.argument;
172 smx_simcall_t saved_req = &state->executed_req;
174 smx_simcall_t req = nullptr;
176 if (saved_req != nullptr) {
177 /* because we got a copy of the executed request, we have to fetch the
178 real one, pointed by the request field of the issuer process */
179 const smx_actor_t issuer = MC_smx_simcall_get_issuer(saved_req);
180 req = &issuer->simcall;
182 /* Debug information */
183 XBT_DEBUG("Replay (depth = %d) : %s (%p)",
185 simgrid::mc::request_to_string(
186 req, req_num, simgrid::mc::RequestType::simix).c_str(),
190 this->getSession().execute(state->transition);
193 /* Update statistics */
194 visitedPairsCount_++;
195 mc_model_checker->executed_transitions++;
201 XBT_DEBUG("**** End Replay ****");
205 * @brief Checks whether a given pair has already been visited by the algorithm.
207 int LivenessChecker::insertVisitedPair(std::shared_ptr<VisitedPair> visited_pair, simgrid::mc::Pair* pair)
209 if (_sg_mc_max_visited_states == 0)
212 if (visited_pair == nullptr)
214 std::make_shared<VisitedPair>(pair->num, pair->automaton_state, pair->atomic_propositions, pair->graph_state);
216 auto range = boost::range::equal_range(visitedPairs_, visited_pair.get(),
217 simgrid::mc::DerefAndCompareByActorsCountAndUsedHeap());
219 for (auto i = range.first; i != range.second; ++i) {
220 VisitedPair* pair_test = i->get();
221 if (xbt_automaton_state_compare(
222 pair_test->automaton_state, visited_pair->automaton_state) != 0
223 || *(pair_test->atomic_propositions) != *(visited_pair->atomic_propositions)
224 || this->compare(pair_test, visited_pair.get()) != 0)
226 if (pair_test->other_num == -1)
227 visited_pair->other_num = pair_test->num;
229 visited_pair->other_num = pair_test->other_num;
230 if (dot_output == nullptr)
231 XBT_DEBUG("Pair %d already visited ! (equal to pair %d)", visited_pair->num, pair_test->num);
233 XBT_DEBUG("Pair %d already visited ! (equal to pair %d (pair %d in dot_output))",
234 visited_pair->num, pair_test->num, visited_pair->other_num);
235 (*i) = std::move(visited_pair);
236 return (*i)->other_num;
239 visitedPairs_.insert(range.first, std::move(visited_pair));
240 this->purgeVisitedPairs();
244 void LivenessChecker::purgeVisitedPairs()
246 if (_sg_mc_max_visited_states != 0 && visitedPairs_.size() > (std::size_t)_sg_mc_max_visited_states) {
247 // Remove the oldest entry with a linear search:
248 visitedPairs_.erase(boost::min_element(visitedPairs_,
249 [](std::shared_ptr<VisitedPair> const a, std::shared_ptr<VisitedPair> const& b) {
250 return a->num < b->num; } ));
254 LivenessChecker::LivenessChecker(Session& s) : Checker(s)
258 RecordTrace LivenessChecker::getRecordTrace() // override
261 for (std::shared_ptr<Pair> const& pair : explorationStack_)
262 res.push_back(pair->graph_state->getTransition());
266 void LivenessChecker::logState() // override
268 XBT_INFO("Expanded pairs = %lu", expandedPairsCount_);
269 XBT_INFO("Visited pairs = %lu", visitedPairsCount_);
270 XBT_INFO("Executed transitions = %lu", mc_model_checker->executed_transitions);
273 void LivenessChecker::showAcceptanceCycle(std::size_t depth)
275 XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
276 XBT_INFO("| ACCEPTANCE CYCLE |");
277 XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
278 XBT_INFO("Counter-example that violates formula :");
279 simgrid::mc::dumpRecordPath();
280 for (auto const& s : this->getTextualTrace())
281 XBT_INFO("%s", s.c_str());
282 simgrid::mc::session->logState();
283 XBT_INFO("Counter-example depth : %zu", depth);
286 std::vector<std::string> LivenessChecker::getTextualTrace() // override
288 std::vector<std::string> trace;
289 for (std::shared_ptr<Pair> const& pair : explorationStack_) {
290 int req_num = pair->graph_state->transition.argument;
291 smx_simcall_t req = &pair->graph_state->executed_req;
292 if (req && req->call != SIMCALL_NONE)
293 trace.push_back(simgrid::mc::request_to_string(
294 req, req_num, simgrid::mc::RequestType::executed));
299 std::shared_ptr<Pair> LivenessChecker::newPair(Pair* current_pair, xbt_automaton_state_t state,
300 std::shared_ptr<const std::vector<int>> propositions)
302 expandedPairsCount_++;
303 std::shared_ptr<Pair> next_pair = std::make_shared<Pair>(expandedPairsCount_);
304 next_pair->automaton_state = state;
305 next_pair->graph_state = std::shared_ptr<simgrid::mc::State>(new simgrid::mc::State(++expandedStatesCount_));
306 next_pair->atomic_propositions = std::move(propositions);
308 next_pair->depth = current_pair->depth + 1;
310 next_pair->depth = 1;
311 /* Get enabled actors and insert them in the interleave set of the next graph_state */
312 for (auto& actor : mc_model_checker->process().actors())
313 if (simgrid::mc::actor_is_enabled(actor.copy.getBuffer()))
314 next_pair->graph_state->addInterleavingSet(actor.copy.getBuffer());
315 next_pair->requests = next_pair->graph_state->interleaveSize();
316 /* FIXME : get search_cycle value for each accepting state */
317 if (next_pair->automaton_state->type == 1 || (current_pair && current_pair->search_cycle))
318 next_pair->search_cycle = true;
320 next_pair->search_cycle = false;
324 void LivenessChecker::backtrack()
326 /* Traverse the stack backwards until a pair with a non empty interleave
327 set is found, deleting all the pairs that have it empty in the way. */
328 while (not explorationStack_.empty()) {
329 std::shared_ptr<simgrid::mc::Pair> current_pair = explorationStack_.back();
330 explorationStack_.pop_back();
331 if (current_pair->requests > 0) {
332 /* We found a backtracking point */
333 XBT_DEBUG("Backtracking to depth %d", current_pair->depth);
334 explorationStack_.push_back(std::move(current_pair));
336 XBT_DEBUG("Backtracking done");
339 XBT_DEBUG("Delete pair %d at depth %d", current_pair->num, current_pair->depth);
340 if (current_pair->automaton_state->type == 1)
341 this->removeAcceptancePair(current_pair->num);
346 void LivenessChecker::run()
348 XBT_INFO("Check the liveness property %s", _sg_mc_property_file.get().c_str());
349 MC_automaton_load(_sg_mc_property_file.get().c_str());
351 XBT_DEBUG("Starting the liveness algorithm");
352 simgrid::mc::session->initialize();
355 this->previousPair_ = 0;
357 std::shared_ptr<const std::vector<int>> propos = this->getPropositionValues();
359 // For each initial state of the property automaton, push a
360 // (application_state, automaton_state) pair to the exploration stack:
361 unsigned int cursor = 0;
362 xbt_automaton_state_t automaton_state;
363 xbt_dynar_foreach (simgrid::mc::property_automaton->states, cursor, automaton_state)
364 if (automaton_state->type == -1)
365 explorationStack_.push_back(this->newPair(nullptr, automaton_state, propos));
367 /* Actually run the double DFS search for counter-examples */
368 while (not explorationStack_.empty()) {
369 std::shared_ptr<Pair> current_pair = explorationStack_.back();
371 /* Update current state in buchi automaton */
372 simgrid::mc::property_automaton->current_state = current_pair->automaton_state;
375 "********************* ( Depth = %d, search_cycle = %d, interleave size = %zu, pair_num = %d, requests = %d)",
376 current_pair->depth, current_pair->search_cycle, current_pair->graph_state->interleaveSize(), current_pair->num,
377 current_pair->requests);
379 if (current_pair->requests == 0) {
384 std::shared_ptr<VisitedPair> reached_pair;
385 if (current_pair->automaton_state->type == 1 && not current_pair->exploration_started) {
386 reached_pair = this->insertAcceptancePair(current_pair.get());
387 if (reached_pair == nullptr) {
388 this->showAcceptanceCycle(current_pair->depth);
389 throw simgrid::mc::LivenessError();
393 /* Pair already visited ? stop the exploration on the current path */
394 if (not current_pair->exploration_started) {
395 int visited_num = this->insertVisitedPair(reached_pair, current_pair.get());
396 if (visited_num != -1) {
397 if (dot_output != nullptr) {
398 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", this->previousPair_, visited_num,
399 this->previousRequest_.c_str());
402 XBT_DEBUG("Pair already visited (equal to pair %d), exploration on the current path stopped.", visited_num);
403 current_pair->requests = 0;
409 smx_simcall_t req = MC_state_get_request(current_pair->graph_state.get());
410 int req_num = current_pair->graph_state->transition.argument;
412 if (dot_output != nullptr) {
413 if (this->previousPair_ != 0 && this->previousPair_ != current_pair->num) {
414 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n",
415 this->previousPair_, current_pair->num,
416 this->previousRequest_.c_str());
417 this->previousRequest_.clear();
419 this->previousPair_ = current_pair->num;
420 this->previousRequest_ = simgrid::mc::request_get_dot_output(req, req_num);
421 if (current_pair->search_cycle)
422 fprintf(dot_output, "%d [shape=doublecircle];\n", current_pair->num);
426 XBT_DEBUG("Execute: %s",
427 simgrid::mc::request_to_string(
428 req, req_num, simgrid::mc::RequestType::simix).c_str());
431 mc_model_checker->executed_transitions++;
432 if (not current_pair->exploration_started)
433 visitedPairsCount_++;
435 /* Answer the request */
436 mc_model_checker->handle_simcall(current_pair->graph_state->transition);
438 /* Wait for requests (schedules processes) */
439 mc_model_checker->wait_for_requests();
441 current_pair->requests--;
442 current_pair->exploration_started = true;
444 /* Get values of atomic propositions (variables used in the property formula) */
445 std::shared_ptr<const std::vector<int>> prop_values = this->getPropositionValues();
447 // For each enabled transition in the property automaton, push a
448 // (application_state, automaton_state) pair to the exploration stack:
449 for (int i = xbt_dynar_length(current_pair->automaton_state->out) - 1; i >= 0; i--) {
450 xbt_automaton_transition_t transition_succ = (xbt_automaton_transition_t)xbt_dynar_get_as(
451 current_pair->automaton_state->out, i, xbt_automaton_transition_t);
452 if (evaluate_label(transition_succ->label, *prop_values))
453 explorationStack_.push_back(this->newPair(
454 current_pair.get(), transition_succ->dst, prop_values));
459 XBT_INFO("No property violation found.");
460 simgrid::mc::session->logState();
463 Checker* createLivenessChecker(Session& s)
465 return new LivenessChecker(s);