1 /* Copyright (c) 2011-2020. 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. */
6 #include "src/mc/checker/LivenessChecker.hpp"
7 #include "src/mc/Session.hpp"
8 #include "src/mc/mc_config.hpp"
9 #include "src/mc/mc_exit.hpp"
10 #include "src/mc/mc_private.hpp"
11 #include "src/mc/mc_request.hpp"
12 #include "src/mc/mc_smx.hpp"
13 #include "src/mc/mc_api.hpp"
15 #include <boost/range/algorithm.hpp>
18 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_liveness, mc, "Logging specific to algorithms for liveness properties verification");
20 using mcapi = simgrid::mc::mc_api;
22 /********* Static functions *********/
27 VisitedPair::VisitedPair(int pair_num, xbt_automaton_state_t automaton_state,
28 std::shared_ptr<const std::vector<int>> atomic_propositions,
29 std::shared_ptr<State> graph_state)
30 : num(pair_num), automaton_state(automaton_state)
32 this->graph_state = std::move(graph_state);
33 if (this->graph_state->system_state_ == nullptr)
34 this->graph_state->system_state_ = std::make_shared<Snapshot>(pair_num);
35 this->heap_bytes_used = mcapi::get().get_remote_heap_bytes();
36 this->actors_count = mc_model_checker->get_remote_simulation().actors().size();
39 this->atomic_propositions = std::move(atomic_propositions);
42 static bool evaluate_label(const xbt_automaton_exp_label* l, std::vector<int> const& values)
45 case xbt_automaton_exp_label::AUT_OR:
46 return evaluate_label(l->u.or_and.left_exp, values)
47 || evaluate_label(l->u.or_and.right_exp, values);
48 case xbt_automaton_exp_label::AUT_AND:
49 return evaluate_label(l->u.or_and.left_exp, values)
50 && evaluate_label(l->u.or_and.right_exp, values);
51 case xbt_automaton_exp_label::AUT_NOT:
52 return not evaluate_label(l->u.exp_not, values);
53 case xbt_automaton_exp_label::AUT_PREDICAT:{
54 auto cursor = mcapi::get().compare_automaton_exp_lable(l, values);
56 return values[cursor] != 0;
57 xbt_die("Missing predicate");
60 case xbt_automaton_exp_label::AUT_ONE:
63 xbt_die("Unexpected value for automaton");
67 Pair::Pair(unsigned long expanded_pairs) : num(expanded_pairs)
70 std::shared_ptr<const std::vector<int>> LivenessChecker::get_proposition_values() const
72 auto values = mcapi::get().automaton_propositional_symbol_evaluate();
73 return std::make_shared<const std::vector<int>>(std::move(values));
76 std::shared_ptr<VisitedPair> LivenessChecker::insert_acceptance_pair(simgrid::mc::Pair* pair)
79 std::make_shared<VisitedPair>(pair->num, pair->automaton_state, pair->atomic_propositions, pair->graph_state);
81 auto res = boost::range::equal_range(acceptance_pairs_, new_pair.get(), mcapi::get().compare_pair());
83 if (pair->search_cycle) for (auto i = res.first; i != res.second; ++i) {
84 std::shared_ptr<simgrid::mc::VisitedPair> const& pair_test = *i;
85 if (mcapi::get().automaton_state_compare(pair_test->automaton_state, new_pair->automaton_state) != 0 ||
86 *(pair_test->atomic_propositions) != *(new_pair->atomic_propositions) ||
87 not mcapi::get().snapshot_equal(pair_test->graph_state->system_state_.get(), new_pair->graph_state->system_state_.get()))
89 XBT_INFO("Pair %d already reached (equal to pair %d) !", new_pair->num, pair_test->num);
90 exploration_stack_.pop_back();
91 if (dot_output != nullptr)
92 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", this->previous_pair_, pair_test->num,
93 this->previous_request_.c_str());
97 acceptance_pairs_.insert(res.first, new_pair);
101 void LivenessChecker::remove_acceptance_pair(int pair_num)
103 for (auto i = acceptance_pairs_.begin(); i != acceptance_pairs_.end(); ++i)
104 if ((*i)->num == pair_num) {
105 acceptance_pairs_.erase(i);
110 void LivenessChecker::replay()
112 XBT_DEBUG("**** Begin Replay ****");
114 /* Intermediate backtracking */
115 if(_sg_mc_checkpoint > 0) {
116 const Pair* pair = exploration_stack_.back().get();
117 if (pair->graph_state->system_state_) {
118 pair->graph_state->system_state_->restore(&mc_model_checker->get_remote_simulation());
123 /* Restore the initial state */
124 mc::session->restore_initial_state();
126 /* Traverse the stack from the initial state and re-execute the transitions */
128 for (std::shared_ptr<Pair> const& pair : exploration_stack_) {
129 if (pair == exploration_stack_.back())
132 std::shared_ptr<State> state = pair->graph_state;
134 if (pair->exploration_started) {
135 int req_num = state->transition_.argument_;
136 const s_smx_simcall* saved_req = &state->executed_req_;
138 smx_simcall_t req = nullptr;
140 /* because we got a copy of the executed request, we have to fetch the
141 real one, pointed by the request field of the issuer process */
142 const smx_actor_t issuer = MC_smx_simcall_get_issuer(saved_req);
143 req = &issuer->simcall_;
145 /* Debug information */
146 XBT_DEBUG("Replay (depth = %d) : %s (%p)", depth,
147 mcapi::get().request_to_string(req, req_num, simgrid::mc::RequestType::simix).c_str(), state.get());
149 this->get_session().execute(state->transition_);
152 /* Update statistics */
153 visited_pairs_count_++;
154 mc_model_checker->executed_transitions++;
158 XBT_DEBUG("**** End Replay ****");
162 * @brief Checks whether a given pair has already been visited by the algorithm.
164 int LivenessChecker::insert_visited_pair(std::shared_ptr<VisitedPair> visited_pair, simgrid::mc::Pair* pair)
166 if (_sg_mc_max_visited_states == 0)
169 if (visited_pair == nullptr)
171 std::make_shared<VisitedPair>(pair->num, pair->automaton_state, pair->atomic_propositions, pair->graph_state);
173 auto range = boost::range::equal_range(visited_pairs_, visited_pair.get(), mcapi::get().compare_pair());
175 for (auto i = range.first; i != range.second; ++i) {
176 const VisitedPair* pair_test = i->get();
177 if (mcapi::get().automaton_state_compare(pair_test->automaton_state, visited_pair->automaton_state) != 0 ||
178 *(pair_test->atomic_propositions) != *(visited_pair->atomic_propositions) ||
179 not mcapi::get().snapshot_equal(pair_test->graph_state->system_state_.get(), visited_pair->graph_state->system_state_.get()))
181 if (pair_test->other_num == -1)
182 visited_pair->other_num = pair_test->num;
184 visited_pair->other_num = pair_test->other_num;
185 if (dot_output == nullptr)
186 XBT_DEBUG("Pair %d already visited ! (equal to pair %d)", visited_pair->num, pair_test->num);
188 XBT_DEBUG("Pair %d already visited ! (equal to pair %d (pair %d in dot_output))",
189 visited_pair->num, pair_test->num, visited_pair->other_num);
190 (*i) = std::move(visited_pair);
191 return (*i)->other_num;
194 visited_pairs_.insert(range.first, std::move(visited_pair));
195 this->purge_visited_pairs();
199 void LivenessChecker::purge_visited_pairs()
201 if (_sg_mc_max_visited_states != 0 && visited_pairs_.size() > (std::size_t)_sg_mc_max_visited_states) {
202 // Remove the oldest entry with a linear search:
203 visited_pairs_.erase(
204 boost::min_element(visited_pairs_, [](std::shared_ptr<VisitedPair> const a,
205 std::shared_ptr<VisitedPair> const& b) { return a->num < b->num; }));
209 LivenessChecker::LivenessChecker(Session& s) : Checker(s)
213 RecordTrace LivenessChecker::get_record_trace() // override
216 for (std::shared_ptr<Pair> const& pair : exploration_stack_)
217 res.push_back(pair->graph_state->get_transition());
221 void LivenessChecker::log_state() // override
223 XBT_INFO("Expanded pairs = %lu", expanded_pairs_count_);
224 XBT_INFO("Visited pairs = %lu", visited_pairs_count_);
225 XBT_INFO("Executed transitions = %lu", mcapi::get().mc_get_executed_trans());
228 void LivenessChecker::show_acceptance_cycle(std::size_t depth)
230 XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
231 XBT_INFO("| ACCEPTANCE CYCLE |");
232 XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
233 XBT_INFO("Counter-example that violates formula:");
234 for (auto const& s : this->get_textual_trace())
235 XBT_INFO(" %s", s.c_str());
236 mcapi::get().dump_record_path();
237 mcapi::get().log_state();
238 XBT_INFO("Counter-example depth: %zu", depth);
241 std::vector<std::string> LivenessChecker::get_textual_trace() // override
243 std::vector<std::string> trace;
244 for (std::shared_ptr<Pair> const& pair : exploration_stack_) {
245 int req_num = pair->graph_state->transition_.argument_;
246 smx_simcall_t req = &pair->graph_state->executed_req_;
247 if (req->call_ != simix::Simcall::NONE)
248 trace.push_back(mcapi::get().request_to_string(req, req_num, RequestType::executed));
253 std::shared_ptr<Pair> LivenessChecker::create_pair(const Pair* current_pair, xbt_automaton_state_t state,
254 std::shared_ptr<const std::vector<int>> propositions)
256 ++expanded_pairs_count_;
257 ++expanded_states_count_;
258 auto next_pair = std::make_shared<Pair>(expanded_pairs_count_);
259 next_pair->automaton_state = state;
260 next_pair->graph_state = std::make_shared<State>(expanded_states_count_);
261 next_pair->atomic_propositions = std::move(propositions);
263 next_pair->depth = current_pair->depth + 1;
265 next_pair->depth = 1;
266 /* Get enabled actors and insert them in the interleave set of the next graph_state */
267 auto actors = mcapi::get().get_actors();
268 for (auto& actor : actors)
269 if (mcapi::get().actor_is_enabled(actor.copy.get_buffer()->get_pid()))
270 next_pair->graph_state->add_interleaving_set(actor.copy.get_buffer());
271 next_pair->requests = next_pair->graph_state->interleave_size();
272 /* FIXME : get search_cycle value for each accepting state */
273 if (next_pair->automaton_state->type == 1 || (current_pair && current_pair->search_cycle))
274 next_pair->search_cycle = true;
276 next_pair->search_cycle = false;
280 void LivenessChecker::backtrack()
282 /* Traverse the stack backwards until a pair with a non empty interleave
283 set is found, deleting all the pairs that have it empty in the way. */
284 while (not exploration_stack_.empty()) {
285 std::shared_ptr<simgrid::mc::Pair> current_pair = exploration_stack_.back();
286 exploration_stack_.pop_back();
287 if (current_pair->requests > 0) {
288 /* We found a backtracking point */
289 XBT_DEBUG("Backtracking to depth %d", current_pair->depth);
290 exploration_stack_.push_back(std::move(current_pair));
292 XBT_DEBUG("Backtracking done");
295 XBT_DEBUG("Delete pair %d at depth %d", current_pair->num, current_pair->depth);
296 if (current_pair->automaton_state->type == 1)
297 this->remove_acceptance_pair(current_pair->num);
302 void LivenessChecker::run()
304 XBT_INFO("Check the liveness property %s", _sg_mc_property_file.get().c_str());
305 mcapi::get().automaton_load(_sg_mc_property_file.get().c_str());
307 XBT_DEBUG("Starting the liveness algorithm");
308 mcapi::get().session_initialize();
311 this->previous_pair_ = 0;
313 std::shared_ptr<const std::vector<int>> propos = this->get_proposition_values();
315 // For each initial state of the property automaton, push a
316 // (application_state, automaton_state) pair to the exploration stack:
317 auto automaton_stack = mcapi::get().get_automaton_state();
318 std::for_each(automaton_stack.begin(), automaton_stack.end(), [&](xbt_automaton_state_t const& automaton_state) {
319 if (automaton_state->type == -1)
320 exploration_stack_.push_back(this->create_pair(nullptr, automaton_state, propos));
323 /* Actually run the double DFS search for counter-examples */
324 while (not exploration_stack_.empty()) {
325 std::shared_ptr<Pair> current_pair = exploration_stack_.back();
327 /* Update current state in buchi automaton */
328 mcapi::get().set_property_automaton(current_pair->automaton_state);
331 "********************* ( Depth = %d, search_cycle = %d, interleave size = %zu, pair_num = %d, requests = %d)",
332 current_pair->depth, current_pair->search_cycle, current_pair->graph_state->interleave_size(),
333 current_pair->num, current_pair->requests);
335 if (current_pair->requests == 0) {
340 std::shared_ptr<VisitedPair> reached_pair;
341 if (current_pair->automaton_state->type == 1 && not current_pair->exploration_started) {
342 reached_pair = this->insert_acceptance_pair(current_pair.get());
343 if (reached_pair == nullptr) {
344 this->show_acceptance_cycle(current_pair->depth);
345 throw LivenessError();
349 /* Pair already visited ? stop the exploration on the current path */
350 if (not current_pair->exploration_started) {
351 int visited_num = this->insert_visited_pair(reached_pair, current_pair.get());
352 if (visited_num != -1) {
353 if (dot_output != nullptr) {
354 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", this->previous_pair_, visited_num,
355 this->previous_request_.c_str());
358 XBT_DEBUG("Pair already visited (equal to pair %d), exploration on the current path stopped.", visited_num);
359 current_pair->requests = 0;
365 smx_simcall_t req = mcapi::get().mc_state_choose_request(current_pair->graph_state.get());
366 int req_num = current_pair->graph_state->transition_.argument_;
368 if (dot_output != nullptr) {
369 if (this->previous_pair_ != 0 && this->previous_pair_ != current_pair->num) {
370 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", this->previous_pair_, current_pair->num,
371 this->previous_request_.c_str());
372 this->previous_request_.clear();
374 this->previous_pair_ = current_pair->num;
375 this->previous_request_ = mcapi::get().request_get_dot_output(req, req_num);
376 if (current_pair->search_cycle)
377 fprintf(dot_output, "%d [shape=doublecircle];\n", current_pair->num);
381 XBT_DEBUG("Execute: %s", mcapi::get().request_to_string(req, req_num, RequestType::simix).c_str());
384 mcapi::get().mc_inc_executed_trans();
386 if (not current_pair->exploration_started)
387 visited_pairs_count_++;
389 /* Answer the request */
390 mcapi::get().handle_simcall(current_pair->graph_state->transition_);
392 /* Wait for requests (schedules processes) */
393 mcapi::get().mc_wait_for_requests();
395 current_pair->requests--;
396 current_pair->exploration_started = true;
398 /* Get values of atomic propositions (variables used in the property formula) */
399 std::shared_ptr<const std::vector<int>> prop_values = this->get_proposition_values();
401 // For each enabled transition in the property automaton, push a
402 // (application_state, automaton_state) pair to the exploration stack:
403 for (int i = mcapi::get().get_dynar_length(current_pair->automaton_state->out) - 1; i >= 0; i--) {
404 auto transition_succ_label = mcapi::get().get_automaton_transition_label(current_pair->automaton_state->out, i);
405 auto transition_succ_dst = mcapi::get().get_automaton_transition_dst(current_pair->automaton_state->out, i);
406 if (evaluate_label(transition_succ_label, *prop_values))
407 exploration_stack_.push_back(this->create_pair(current_pair.get(), transition_succ_dst, prop_values));
411 XBT_INFO("No property violation found.");
412 mcapi::get().log_state();
415 Checker* createLivenessChecker(Session& s)
417 return new LivenessChecker(s);
421 } // namespace simgrid