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 RemoteSimulation* process = &(mc_model_checker->get_remote_simulation());
34 this->graph_state = std::move(graph_state);
35 if (this->graph_state->system_state_ == nullptr)
36 this->graph_state->system_state_ = std::make_shared<Snapshot>(pair_num);
37 this->heap_bytes_used = mmalloc_get_bytes_used_remote(process->get_heap()->heaplimit, process->get_malloc_info());
39 this->actors_count = mc_model_checker->get_remote_simulation().actors().size();
42 this->atomic_propositions = std::move(atomic_propositions);
45 static bool evaluate_label(const xbt_automaton_exp_label* l, std::vector<int> const& values)
48 case xbt_automaton_exp_label::AUT_OR:
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_AND:
52 return evaluate_label(l->u.or_and.left_exp, values)
53 && evaluate_label(l->u.or_and.right_exp, values);
54 case xbt_automaton_exp_label::AUT_NOT:
55 return not evaluate_label(l->u.exp_not, values);
56 case xbt_automaton_exp_label::AUT_PREDICAT:{
57 auto cursor = mcapi::get().compare_automaton_exp_lable(l, values);
59 return values[cursor] != 0;
60 xbt_die("Missing predicate");
63 case xbt_automaton_exp_label::AUT_ONE:
66 xbt_die("Unexpected value for automaton");
70 Pair::Pair(unsigned long expanded_pairs) : num(expanded_pairs)
73 std::shared_ptr<const std::vector<int>> LivenessChecker::get_proposition_values() const
75 auto values = mcapi::get().automaton_propositional_symbol_evaluate();
76 return std::make_shared<const std::vector<int>>(std::move(values));
79 std::shared_ptr<VisitedPair> LivenessChecker::insert_acceptance_pair(simgrid::mc::Pair* pair)
82 std::make_shared<VisitedPair>(pair->num, pair->automaton_state, pair->atomic_propositions, pair->graph_state);
84 auto res = boost::range::equal_range(acceptance_pairs_, new_pair.get(), mcapi::get().compare_pair());
86 if (pair->search_cycle) for (auto i = res.first; i != res.second; ++i) {
87 std::shared_ptr<simgrid::mc::VisitedPair> const& pair_test = *i;
88 if (mcapi::get().automaton_state_compare(pair_test->automaton_state, new_pair->automaton_state) != 0 ||
89 *(pair_test->atomic_propositions) != *(new_pair->atomic_propositions) ||
90 not mcapi::get().snapshot_equal(pair_test->graph_state->system_state_.get(), new_pair->graph_state->system_state_.get()))
92 XBT_INFO("Pair %d already reached (equal to pair %d) !", new_pair->num, pair_test->num);
93 exploration_stack_.pop_back();
94 if (dot_output != nullptr)
95 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", this->previous_pair_, pair_test->num,
96 this->previous_request_.c_str());
100 acceptance_pairs_.insert(res.first, new_pair);
104 void LivenessChecker::remove_acceptance_pair(int pair_num)
106 for (auto i = acceptance_pairs_.begin(); i != acceptance_pairs_.end(); ++i)
107 if ((*i)->num == pair_num) {
108 acceptance_pairs_.erase(i);
113 void LivenessChecker::replay()
115 XBT_DEBUG("**** Begin Replay ****");
117 /* Intermediate backtracking */
118 if(_sg_mc_checkpoint > 0) {
119 const Pair* pair = exploration_stack_.back().get();
120 if (pair->graph_state->system_state_) {
121 pair->graph_state->system_state_->restore(&mc_model_checker->get_remote_simulation());
126 /* Restore the initial state */
127 mc::session->restore_initial_state();
129 /* Traverse the stack from the initial state and re-execute the transitions */
131 for (std::shared_ptr<Pair> const& pair : exploration_stack_) {
132 if (pair == exploration_stack_.back())
135 std::shared_ptr<State> state = pair->graph_state;
137 if (pair->exploration_started) {
138 int req_num = state->transition_.argument_;
139 const s_smx_simcall* saved_req = &state->executed_req_;
141 smx_simcall_t req = nullptr;
143 /* because we got a copy of the executed request, we have to fetch the
144 real one, pointed by the request field of the issuer process */
145 const smx_actor_t issuer = MC_smx_simcall_get_issuer(saved_req);
146 req = &issuer->simcall_;
148 /* Debug information */
149 XBT_DEBUG("Replay (depth = %d) : %s (%p)", depth,
150 mcapi::get().request_to_string(req, req_num, simgrid::mc::RequestType::simix).c_str(), state.get());
152 this->get_session().execute(state->transition_);
155 /* Update statistics */
156 visited_pairs_count_++;
157 mc_model_checker->executed_transitions++;
161 XBT_DEBUG("**** End Replay ****");
165 * @brief Checks whether a given pair has already been visited by the algorithm.
167 int LivenessChecker::insert_visited_pair(std::shared_ptr<VisitedPair> visited_pair, simgrid::mc::Pair* pair)
169 if (_sg_mc_max_visited_states == 0)
172 if (visited_pair == nullptr)
174 std::make_shared<VisitedPair>(pair->num, pair->automaton_state, pair->atomic_propositions, pair->graph_state);
176 auto range = boost::range::equal_range(visited_pairs_, visited_pair.get(), mcapi::get().compare_pair());
178 for (auto i = range.first; i != range.second; ++i) {
179 const VisitedPair* pair_test = i->get();
180 if (mcapi::get().automaton_state_compare(pair_test->automaton_state, visited_pair->automaton_state) != 0 ||
181 *(pair_test->atomic_propositions) != *(visited_pair->atomic_propositions) ||
182 not mcapi::get().snapshot_equal(pair_test->graph_state->system_state_.get(), visited_pair->graph_state->system_state_.get()))
184 if (pair_test->other_num == -1)
185 visited_pair->other_num = pair_test->num;
187 visited_pair->other_num = pair_test->other_num;
188 if (dot_output == nullptr)
189 XBT_DEBUG("Pair %d already visited ! (equal to pair %d)", visited_pair->num, pair_test->num);
191 XBT_DEBUG("Pair %d already visited ! (equal to pair %d (pair %d in dot_output))",
192 visited_pair->num, pair_test->num, visited_pair->other_num);
193 (*i) = std::move(visited_pair);
194 return (*i)->other_num;
197 visited_pairs_.insert(range.first, std::move(visited_pair));
198 this->purge_visited_pairs();
202 void LivenessChecker::purge_visited_pairs()
204 if (_sg_mc_max_visited_states != 0 && visited_pairs_.size() > (std::size_t)_sg_mc_max_visited_states) {
205 // Remove the oldest entry with a linear search:
206 visited_pairs_.erase(
207 boost::min_element(visited_pairs_, [](std::shared_ptr<VisitedPair> const a,
208 std::shared_ptr<VisitedPair> const& b) { return a->num < b->num; }));
212 LivenessChecker::LivenessChecker(Session& s) : Checker(s)
216 RecordTrace LivenessChecker::get_record_trace() // override
219 for (std::shared_ptr<Pair> const& pair : exploration_stack_)
220 res.push_back(pair->graph_state->get_transition());
224 void LivenessChecker::log_state() // override
226 XBT_INFO("Expanded pairs = %lu", expanded_pairs_count_);
227 XBT_INFO("Visited pairs = %lu", visited_pairs_count_);
228 XBT_INFO("Executed transitions = %lu", mcapi::get().mc_get_executed_trans());
231 void LivenessChecker::show_acceptance_cycle(std::size_t depth)
233 XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
234 XBT_INFO("| ACCEPTANCE CYCLE |");
235 XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
236 XBT_INFO("Counter-example that violates formula:");
237 for (auto const& s : this->get_textual_trace())
238 XBT_INFO(" %s", s.c_str());
239 mcapi::get().dump_record_path();
240 mcapi::get().log_state();
241 XBT_INFO("Counter-example depth: %zu", depth);
244 std::vector<std::string> LivenessChecker::get_textual_trace() // override
246 std::vector<std::string> trace;
247 for (std::shared_ptr<Pair> const& pair : exploration_stack_) {
248 int req_num = pair->graph_state->transition_.argument_;
249 smx_simcall_t req = &pair->graph_state->executed_req_;
250 if (req->call_ != simix::Simcall::NONE)
251 trace.push_back(mcapi::get().request_to_string(req, req_num, RequestType::executed));
256 std::shared_ptr<Pair> LivenessChecker::create_pair(const Pair* current_pair, xbt_automaton_state_t state,
257 std::shared_ptr<const std::vector<int>> propositions)
259 ++expanded_pairs_count_;
260 ++expanded_states_count_;
261 auto next_pair = std::make_shared<Pair>(expanded_pairs_count_);
262 next_pair->automaton_state = state;
263 next_pair->graph_state = std::make_shared<State>(expanded_states_count_);
264 next_pair->atomic_propositions = std::move(propositions);
266 next_pair->depth = current_pair->depth + 1;
268 next_pair->depth = 1;
269 /* Get enabled actors and insert them in the interleave set of the next graph_state */
270 auto actors = mcapi::get().get_actors();
271 for (auto& actor : actors)
272 if (mcapi::get().actor_is_enabled(actor.copy.get_buffer()->get_pid()))
273 next_pair->graph_state->add_interleaving_set(actor.copy.get_buffer());
274 next_pair->requests = next_pair->graph_state->interleave_size();
275 /* FIXME : get search_cycle value for each accepting state */
276 if (next_pair->automaton_state->type == 1 || (current_pair && current_pair->search_cycle))
277 next_pair->search_cycle = true;
279 next_pair->search_cycle = false;
283 void LivenessChecker::backtrack()
285 /* Traverse the stack backwards until a pair with a non empty interleave
286 set is found, deleting all the pairs that have it empty in the way. */
287 while (not exploration_stack_.empty()) {
288 std::shared_ptr<simgrid::mc::Pair> current_pair = exploration_stack_.back();
289 exploration_stack_.pop_back();
290 if (current_pair->requests > 0) {
291 /* We found a backtracking point */
292 XBT_DEBUG("Backtracking to depth %d", current_pair->depth);
293 exploration_stack_.push_back(std::move(current_pair));
295 XBT_DEBUG("Backtracking done");
298 XBT_DEBUG("Delete pair %d at depth %d", current_pair->num, current_pair->depth);
299 if (current_pair->automaton_state->type == 1)
300 this->remove_acceptance_pair(current_pair->num);
305 void LivenessChecker::run()
307 XBT_INFO("Check the liveness property %s", _sg_mc_property_file.get().c_str());
308 mcapi::get().automaton_load(_sg_mc_property_file.get().c_str());
310 XBT_DEBUG("Starting the liveness algorithm");
311 mcapi::get().session_initialize();
314 this->previous_pair_ = 0;
316 std::shared_ptr<const std::vector<int>> propos = this->get_proposition_values();
318 // For each initial state of the property automaton, push a
319 // (application_state, automaton_state) pair to the exploration stack:
320 auto automaton_stack = mcapi::get().get_automaton_state();
321 std::for_each(automaton_stack.begin(), automaton_stack.end(), [&](xbt_automaton_state_t const& automaton_state) {
322 if (automaton_state->type == -1)
323 exploration_stack_.push_back(this->create_pair(nullptr, automaton_state, propos));
326 /* Actually run the double DFS search for counter-examples */
327 while (not exploration_stack_.empty()) {
328 std::shared_ptr<Pair> current_pair = exploration_stack_.back();
330 /* Update current state in buchi automaton */
331 mcapi::get().set_property_automaton(current_pair->automaton_state);
334 "********************* ( Depth = %d, search_cycle = %d, interleave size = %zu, pair_num = %d, requests = %d)",
335 current_pair->depth, current_pair->search_cycle, current_pair->graph_state->interleave_size(),
336 current_pair->num, current_pair->requests);
338 if (current_pair->requests == 0) {
343 std::shared_ptr<VisitedPair> reached_pair;
344 if (current_pair->automaton_state->type == 1 && not current_pair->exploration_started) {
345 reached_pair = this->insert_acceptance_pair(current_pair.get());
346 if (reached_pair == nullptr) {
347 this->show_acceptance_cycle(current_pair->depth);
348 throw LivenessError();
352 /* Pair already visited ? stop the exploration on the current path */
353 if (not current_pair->exploration_started) {
354 int visited_num = this->insert_visited_pair(reached_pair, current_pair.get());
355 if (visited_num != -1) {
356 if (dot_output != nullptr) {
357 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", this->previous_pair_, visited_num,
358 this->previous_request_.c_str());
361 XBT_DEBUG("Pair already visited (equal to pair %d), exploration on the current path stopped.", visited_num);
362 current_pair->requests = 0;
368 smx_simcall_t req = mcapi::get().mc_state_choose_request(current_pair->graph_state.get());
369 int req_num = current_pair->graph_state->transition_.argument_;
371 if (dot_output != nullptr) {
372 if (this->previous_pair_ != 0 && this->previous_pair_ != current_pair->num) {
373 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", this->previous_pair_, current_pair->num,
374 this->previous_request_.c_str());
375 this->previous_request_.clear();
377 this->previous_pair_ = current_pair->num;
378 this->previous_request_ = mcapi::get().request_get_dot_output(req, req_num);
379 if (current_pair->search_cycle)
380 fprintf(dot_output, "%d [shape=doublecircle];\n", current_pair->num);
384 XBT_DEBUG("Execute: %s", mcapi::get().request_to_string(req, req_num, RequestType::simix).c_str());
387 mcapi::get().mc_inc_executed_trans();
389 if (not current_pair->exploration_started)
390 visited_pairs_count_++;
392 /* Answer the request */
393 mcapi::get().handle_simcall(current_pair->graph_state->transition_);
395 /* Wait for requests (schedules processes) */
396 mcapi::get().mc_wait_for_requests();
398 current_pair->requests--;
399 current_pair->exploration_started = true;
401 /* Get values of atomic propositions (variables used in the property formula) */
402 std::shared_ptr<const std::vector<int>> prop_values = this->get_proposition_values();
404 // For each enabled transition in the property automaton, push a
405 // (application_state, automaton_state) pair to the exploration stack:
406 for (int i = xbt_dynar_length(current_pair->automaton_state->out) - 1; i >= 0; i--) {
407 const xbt_automaton_transition* transition_succ =
408 xbt_dynar_get_as(current_pair->automaton_state->out, i, xbt_automaton_transition_t);
409 if (evaluate_label(transition_succ->label, *prop_values))
410 exploration_stack_.push_back(this->create_pair(current_pair.get(), transition_succ->dst, prop_values));
414 XBT_INFO("No property violation found.");
415 mcapi::get().log_state();
418 Checker* createLivenessChecker(Session& s)
420 return new LivenessChecker(s);
424 } // namespace simgrid