1 /* Copyright (c) 2011-2017. The SimGrid Team.
2 * All rights reserved. */
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. */
12 #include <boost/range/algorithm.hpp>
17 #include <xbt/automaton.h>
18 #include <xbt/dynar.h>
19 #include <xbt/dynar.hpp>
21 #include <xbt/sysdep.h>
23 #include "src/mc/Session.hpp"
24 #include "src/mc/Transition.hpp"
25 #include "src/mc/checker/LivenessChecker.hpp"
26 #include "src/mc/mc_exit.hpp"
27 #include "src/mc/mc_private.hpp"
28 #include "src/mc/mc_private.hpp"
29 #include "src/mc/mc_record.hpp"
30 #include "src/mc/mc_replay.h"
31 #include "src/mc/mc_request.hpp"
32 #include "src/mc/mc_smx.hpp"
33 #include "src/mc/remote/Client.hpp"
35 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_liveness, mc, "Logging specific to algorithms for liveness properties verification");
36 extern std::string _sg_mc_property_file;
38 /********* Static functions *********/
43 VisitedPair::VisitedPair(int pair_num, xbt_automaton_state_t automaton_state,
44 std::shared_ptr<const std::vector<int>> atomic_propositions,
45 std::shared_ptr<simgrid::mc::State> graph_state)
46 : num(pair_num), automaton_state(automaton_state)
48 simgrid::mc::RemoteClient* process = &(mc_model_checker->process());
50 this->graph_state = std::move(graph_state);
51 if(this->graph_state->system_state == nullptr)
52 this->graph_state->system_state = simgrid::mc::take_snapshot(pair_num);
53 this->heap_bytes_used = mmalloc_get_bytes_used_remote(process->get_heap()->heaplimit, process->get_malloc_info());
55 this->actors_count = mc_model_checker->process().actors().size();
58 this->atomic_propositions = std::move(atomic_propositions);
61 static bool evaluate_label(xbt_automaton_exp_label_t l, std::vector<int> const& values)
64 case xbt_automaton_exp_label::AUT_OR:
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_AND:
68 return evaluate_label(l->u.or_and.left_exp, values)
69 && evaluate_label(l->u.or_and.right_exp, values);
70 case xbt_automaton_exp_label::AUT_NOT:
71 return not evaluate_label(l->u.exp_not, values);
72 case xbt_automaton_exp_label::AUT_PREDICAT:{
73 unsigned int cursor = 0;
74 xbt_automaton_propositional_symbol_t p = nullptr;
75 xbt_dynar_foreach(simgrid::mc::property_automaton->propositional_symbols, cursor, p) {
76 if (std::strcmp(xbt_automaton_propositional_symbol_get_name(p), l->u.predicat) == 0)
77 return values[cursor] != 0;
79 xbt_die("Missing predicate");
82 case xbt_automaton_exp_label::AUT_ONE:
85 xbt_die("Unexpected vaue for automaton");
89 Pair::Pair(unsigned long expanded_pairs) : num(expanded_pairs)
92 std::shared_ptr<const std::vector<int>> LivenessChecker::getPropositionValues()
94 std::vector<int> values;
95 unsigned int cursor = 0;
96 xbt_automaton_propositional_symbol_t ps = nullptr;
97 xbt_dynar_foreach(simgrid::mc::property_automaton->propositional_symbols, cursor, ps)
98 values.push_back(xbt_automaton_propositional_symbol_evaluate(ps));
99 return std::make_shared<const std::vector<int>>(std::move(values));
102 int LivenessChecker::compare(simgrid::mc::VisitedPair* state1, simgrid::mc::VisitedPair* state2)
104 simgrid::mc::Snapshot* s1 = state1->graph_state->system_state.get();
105 simgrid::mc::Snapshot* s2 = state2->graph_state->system_state.get();
106 int num1 = state1->num;
107 int num2 = state2->num;
108 return simgrid::mc::snapshot_compare(num1, s1, num2, s2);
111 std::shared_ptr<VisitedPair> LivenessChecker::insertAcceptancePair(simgrid::mc::Pair* pair)
113 std::shared_ptr<VisitedPair> new_pair = std::make_shared<VisitedPair>(
114 pair->num, pair->automaton_state, pair->atomic_propositions,
117 auto res = boost::range::equal_range(acceptancePairs_, new_pair.get(),
118 simgrid::mc::DerefAndCompareByActorsCountAndUsedHeap());
120 if (pair->search_cycle) for (auto i = res.first; i != res.second; ++i) {
121 std::shared_ptr<simgrid::mc::VisitedPair> const& pair_test = *i;
122 if (xbt_automaton_state_compare(
123 pair_test->automaton_state, new_pair->automaton_state) != 0
124 || *(pair_test->atomic_propositions) != *(new_pair->atomic_propositions)
125 || this->compare(pair_test.get(), new_pair.get()) != 0)
127 XBT_INFO("Pair %d already reached (equal to pair %d) !", new_pair->num, pair_test->num);
128 explorationStack_.pop_back();
129 if (dot_output != nullptr)
130 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", this->previousPair_, pair_test->num,
131 this->previousRequest_.c_str());
135 acceptancePairs_.insert(res.first, new_pair);
139 void LivenessChecker::removeAcceptancePair(int pair_num)
141 for (auto i = acceptancePairs_.begin(); i != acceptancePairs_.end(); ++i)
142 if ((*i)->num == pair_num) {
143 acceptancePairs_.erase(i);
148 void LivenessChecker::replay()
150 XBT_DEBUG("**** Begin Replay ****");
152 /* Intermediate backtracking */
153 if(_sg_mc_checkpoint > 0) {
154 simgrid::mc::Pair* pair = explorationStack_.back().get();
155 if(pair->graph_state->system_state){
156 simgrid::mc::restore_snapshot(pair->graph_state->system_state);
161 /* Restore the initial state */
162 simgrid::mc::session->restoreInitialState();
164 /* Traverse the stack from the initial state and re-execute the transitions */
166 for (std::shared_ptr<Pair> const& pair : explorationStack_) {
167 if (pair == explorationStack_.back())
170 std::shared_ptr<State> state = pair->graph_state;
172 if (pair->exploration_started) {
174 int req_num = state->transition.argument;
175 smx_simcall_t saved_req = &state->executed_req;
177 smx_simcall_t req = nullptr;
179 if (saved_req != nullptr) {
180 /* because we got a copy of the executed request, we have to fetch the
181 real one, pointed by the request field of the issuer process */
182 const smx_actor_t issuer = MC_smx_simcall_get_issuer(saved_req);
183 req = &issuer->simcall;
185 /* Debug information */
186 XBT_DEBUG("Replay (depth = %d) : %s (%p)",
188 simgrid::mc::request_to_string(
189 req, req_num, simgrid::mc::RequestType::simix).c_str(),
193 this->getSession().execute(state->transition);
196 /* Update statistics */
197 visitedPairsCount_++;
198 mc_model_checker->executed_transitions++;
204 XBT_DEBUG("**** End Replay ****");
208 * \brief Checks whether a given pair has already been visited by the algorithm.
210 int LivenessChecker::insertVisitedPair(std::shared_ptr<VisitedPair> visited_pair, simgrid::mc::Pair* pair)
212 if (_sg_mc_max_visited_states == 0)
215 if (visited_pair == nullptr)
217 std::make_shared<VisitedPair>(pair->num, pair->automaton_state, pair->atomic_propositions, pair->graph_state);
219 auto range = boost::range::equal_range(visitedPairs_, visited_pair.get(),
220 simgrid::mc::DerefAndCompareByActorsCountAndUsedHeap());
222 for (auto i = range.first; i != range.second; ++i) {
223 VisitedPair* pair_test = i->get();
224 if (xbt_automaton_state_compare(
225 pair_test->automaton_state, visited_pair->automaton_state) != 0
226 || *(pair_test->atomic_propositions) != *(visited_pair->atomic_propositions)
227 || this->compare(pair_test, visited_pair.get()) != 0)
229 if (pair_test->other_num == -1)
230 visited_pair->other_num = pair_test->num;
232 visited_pair->other_num = pair_test->other_num;
233 if (dot_output == nullptr)
234 XBT_DEBUG("Pair %d already visited ! (equal to pair %d)", visited_pair->num, pair_test->num);
236 XBT_DEBUG("Pair %d already visited ! (equal to pair %d (pair %d in dot_output))",
237 visited_pair->num, pair_test->num, visited_pair->other_num);
238 (*i) = std::move(visited_pair);
239 return (*i)->other_num;
242 visitedPairs_.insert(range.first, std::move(visited_pair));
243 this->purgeVisitedPairs();
247 void LivenessChecker::purgeVisitedPairs()
249 if (_sg_mc_max_visited_states != 0 && visitedPairs_.size() > (std::size_t)_sg_mc_max_visited_states) {
250 // Remove the oldest entry with a linear search:
251 visitedPairs_.erase(boost::min_element(visitedPairs_,
252 [](std::shared_ptr<VisitedPair> const a, std::shared_ptr<VisitedPair> const& b) {
253 return a->num < b->num; } ));
257 LivenessChecker::LivenessChecker(Session& session) : Checker(session)
261 RecordTrace LivenessChecker::getRecordTrace() // override
264 for (std::shared_ptr<Pair> const& pair : explorationStack_)
265 res.push_back(pair->graph_state->getTransition());
269 void LivenessChecker::logState() // override
271 XBT_INFO("Expanded pairs = %lu", expandedPairsCount_);
272 XBT_INFO("Visited pairs = %lu", visitedPairsCount_);
273 XBT_INFO("Executed transitions = %lu", mc_model_checker->executed_transitions);
276 void LivenessChecker::showAcceptanceCycle(std::size_t depth)
278 XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
279 XBT_INFO("| ACCEPTANCE CYCLE |");
280 XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
281 XBT_INFO("Counter-example that violates formula :");
282 simgrid::mc::dumpRecordPath();
283 for (auto const& s : this->getTextualTrace())
284 XBT_INFO("%s", s.c_str());
285 simgrid::mc::session->logState();
286 XBT_INFO("Counter-example depth : %zu", depth);
289 std::vector<std::string> LivenessChecker::getTextualTrace() // override
291 std::vector<std::string> trace;
292 for (std::shared_ptr<Pair> const& pair : explorationStack_) {
293 int req_num = pair->graph_state->transition.argument;
294 smx_simcall_t req = &pair->graph_state->executed_req;
295 if (req && req->call != SIMCALL_NONE)
296 trace.push_back(simgrid::mc::request_to_string(
297 req, req_num, simgrid::mc::RequestType::executed));
302 std::shared_ptr<Pair> LivenessChecker::newPair(Pair* current_pair, xbt_automaton_state_t state,
303 std::shared_ptr<const std::vector<int>> propositions)
305 expandedPairsCount_++;
306 std::shared_ptr<Pair> next_pair = std::make_shared<Pair>(expandedPairsCount_);
307 next_pair->automaton_state = state;
308 next_pair->graph_state = std::shared_ptr<simgrid::mc::State>(new simgrid::mc::State(++expandedStatesCount_));
309 next_pair->atomic_propositions = std::move(propositions);
311 next_pair->depth = current_pair->depth + 1;
313 next_pair->depth = 1;
314 /* Get enabled actors and insert them in the interleave set of the next graph_state */
315 for (auto& actor : mc_model_checker->process().actors())
316 if (simgrid::mc::actor_is_enabled(actor.copy.getBuffer()))
317 next_pair->graph_state->addInterleavingSet(actor.copy.getBuffer());
318 next_pair->requests = next_pair->graph_state->interleaveSize();
319 /* FIXME : get search_cycle value for each accepting state */
320 if (next_pair->automaton_state->type == 1 || (current_pair && current_pair->search_cycle))
321 next_pair->search_cycle = true;
323 next_pair->search_cycle = false;
327 void LivenessChecker::backtrack()
329 /* Traverse the stack backwards until a pair with a non empty interleave
330 set is found, deleting all the pairs that have it empty in the way. */
331 while (not explorationStack_.empty()) {
332 std::shared_ptr<simgrid::mc::Pair> current_pair = explorationStack_.back();
333 explorationStack_.pop_back();
334 if (current_pair->requests > 0) {
335 /* We found a backtracking point */
336 XBT_DEBUG("Backtracking to depth %d", current_pair->depth);
337 explorationStack_.push_back(std::move(current_pair));
339 XBT_DEBUG("Backtracking done");
342 XBT_DEBUG("Delete pair %d at depth %d", current_pair->num, current_pair->depth);
343 if (current_pair->automaton_state->type == 1)
344 this->removeAcceptancePair(current_pair->num);
349 void LivenessChecker::run()
351 XBT_INFO("Check the liveness property %s", _sg_mc_property_file.c_str());
352 MC_automaton_load(_sg_mc_property_file.c_str());
354 XBT_DEBUG("Starting the liveness algorithm");
355 simgrid::mc::session->initialize();
358 this->previousPair_ = 0;
360 std::shared_ptr<const std::vector<int>> propos = this->getPropositionValues();
362 // For each initial state of the property automaton, push a
363 // (application_state, automaton_state) pair to the exploration stack:
364 unsigned int cursor = 0;
365 xbt_automaton_state_t automaton_state;
366 xbt_dynar_foreach (simgrid::mc::property_automaton->states, cursor, automaton_state)
367 if (automaton_state->type == -1)
368 explorationStack_.push_back(this->newPair(nullptr, automaton_state, propos));
370 /* Actually run the double DFS search for counter-examples */
371 while (not explorationStack_.empty()) {
372 std::shared_ptr<Pair> current_pair = explorationStack_.back();
374 /* Update current state in buchi automaton */
375 simgrid::mc::property_automaton->current_state = current_pair->automaton_state;
378 "********************* ( Depth = %d, search_cycle = %d, interleave size = %zu, pair_num = %d, requests = %d)",
379 current_pair->depth, current_pair->search_cycle, current_pair->graph_state->interleaveSize(), current_pair->num,
380 current_pair->requests);
382 if (current_pair->requests == 0) {
387 std::shared_ptr<VisitedPair> reached_pair;
388 if (current_pair->automaton_state->type == 1 && not current_pair->exploration_started) {
389 reached_pair = this->insertAcceptancePair(current_pair.get());
390 if (reached_pair == nullptr) {
391 this->showAcceptanceCycle(current_pair->depth);
392 throw simgrid::mc::LivenessError();
396 /* Pair already visited ? stop the exploration on the current path */
397 if (not current_pair->exploration_started) {
398 int visited_num = this->insertVisitedPair(reached_pair, current_pair.get());
399 if (visited_num != -1) {
400 if (dot_output != nullptr) {
401 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", this->previousPair_, visited_num,
402 this->previousRequest_.c_str());
405 XBT_DEBUG("Pair already visited (equal to pair %d), exploration on the current path stopped.", visited_num);
406 current_pair->requests = 0;
412 smx_simcall_t req = MC_state_get_request(current_pair->graph_state.get());
413 int req_num = current_pair->graph_state->transition.argument;
415 if (dot_output != nullptr) {
416 if (this->previousPair_ != 0 && this->previousPair_ != current_pair->num) {
417 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n",
418 this->previousPair_, current_pair->num,
419 this->previousRequest_.c_str());
420 this->previousRequest_.clear();
422 this->previousPair_ = current_pair->num;
423 this->previousRequest_ = simgrid::mc::request_get_dot_output(req, req_num);
424 if (current_pair->search_cycle)
425 fprintf(dot_output, "%d [shape=doublecircle];\n", current_pair->num);
429 XBT_DEBUG("Execute: %s",
430 simgrid::mc::request_to_string(
431 req, req_num, simgrid::mc::RequestType::simix).c_str());
434 mc_model_checker->executed_transitions++;
435 if (not current_pair->exploration_started)
436 visitedPairsCount_++;
438 /* Answer the request */
439 mc_model_checker->handle_simcall(current_pair->graph_state->transition);
441 /* Wait for requests (schedules processes) */
442 mc_model_checker->wait_for_requests();
444 current_pair->requests--;
445 current_pair->exploration_started = true;
447 /* Get values of atomic propositions (variables used in the property formula) */
448 std::shared_ptr<const std::vector<int>> prop_values = this->getPropositionValues();
450 // For each enabled transition in the property automaton, push a
451 // (application_state, automaton_state) pair to the exploration stack:
452 for (int cursor = xbt_dynar_length(current_pair->automaton_state->out) - 1; cursor >= 0; cursor--) {
453 xbt_automaton_transition_t transition_succ = (xbt_automaton_transition_t)xbt_dynar_get_as(current_pair->automaton_state->out, cursor, xbt_automaton_transition_t);
454 if (evaluate_label(transition_succ->label, *prop_values))
455 explorationStack_.push_back(this->newPair(
456 current_pair.get(), transition_succ->dst, prop_values));
461 XBT_INFO("No property violation found.");
462 simgrid::mc::session->logState();
465 Checker* createLivenessChecker(Session& session)
467 return new LivenessChecker(session);