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/mc_config.hpp"
8 #include "src/mc/mc_exit.hpp"
9 #include "src/mc/mc_private.hpp"
10 #include "src/mc/mc_request.hpp"
11 #include "src/mc/mc_smx.hpp"
13 #include <boost/range/algorithm.hpp>
16 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_liveness, mc, "Logging specific to algorithms for liveness properties verification");
18 using mcapi = simgrid::mc::mc_api;
20 /********* Static functions *********/
25 VisitedPair::VisitedPair(int pair_num, xbt_automaton_state_t automaton_state,
26 std::shared_ptr<const std::vector<int>> atomic_propositions,
27 std::shared_ptr<State> graph_state)
28 : num(pair_num), automaton_state(automaton_state)
30 this->graph_state = std::move(graph_state);
31 if (this->graph_state->system_state_ == nullptr)
32 this->graph_state->system_state_ = std::make_shared<Snapshot>(pair_num);
33 this->heap_bytes_used = mcapi::get().get_remote_heap_bytes();
34 this->actors_count = mcapi::get().get_actors_size();
36 this->atomic_propositions = std::move(atomic_propositions);
39 static bool evaluate_label(const xbt_automaton_exp_label* l, std::vector<int> const& values)
42 case xbt_automaton_exp_label::AUT_OR:
43 return evaluate_label(l->u.or_and.left_exp, values)
44 || evaluate_label(l->u.or_and.right_exp, values);
45 case xbt_automaton_exp_label::AUT_AND:
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_NOT:
49 return not evaluate_label(l->u.exp_not, values);
50 case xbt_automaton_exp_label::AUT_PREDICAT:{
51 auto cursor = mcapi::get().compare_automaton_exp_label(l);
53 return values[cursor] != 0;
54 xbt_die("Missing predicate");
57 case xbt_automaton_exp_label::AUT_ONE:
60 xbt_die("Unexpected value for automaton");
64 Pair::Pair(unsigned long expanded_pairs) : num(expanded_pairs)
67 std::shared_ptr<const std::vector<int>> LivenessChecker::get_proposition_values() const
69 auto values = mcapi::get().automaton_propositional_symbol_evaluate();
70 return std::make_shared<const std::vector<int>>(std::move(values));
73 std::shared_ptr<VisitedPair> LivenessChecker::insert_acceptance_pair(simgrid::mc::Pair* pair)
76 std::make_shared<VisitedPair>(pair->num, pair->automaton_state, pair->atomic_propositions, pair->graph_state);
78 auto res = boost::range::equal_range(acceptance_pairs_, new_pair.get(), mcapi::get().compare_pair());
80 if (pair->search_cycle) for (auto i = res.first; i != res.second; ++i) {
81 std::shared_ptr<simgrid::mc::VisitedPair> const& pair_test = *i;
82 if (mcapi::get().automaton_state_compare(pair_test->automaton_state, new_pair->automaton_state) != 0 ||
83 *(pair_test->atomic_propositions) != *(new_pair->atomic_propositions) ||
84 not mcapi::get().snapshot_equal(pair_test->graph_state->system_state_.get(), new_pair->graph_state->system_state_.get()))
86 XBT_INFO("Pair %d already reached (equal to pair %d) !", new_pair->num, pair_test->num);
87 exploration_stack_.pop_back();
88 if (dot_output != nullptr)
89 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", this->previous_pair_, pair_test->num,
90 this->previous_request_.c_str());
94 acceptance_pairs_.insert(res.first, new_pair);
98 void LivenessChecker::remove_acceptance_pair(int pair_num)
100 for (auto i = acceptance_pairs_.begin(); i != acceptance_pairs_.end(); ++i)
101 if ((*i)->num == pair_num) {
102 acceptance_pairs_.erase(i);
107 void LivenessChecker::replay()
109 XBT_DEBUG("**** Begin Replay ****");
111 /* Intermediate backtracking */
112 if(_sg_mc_checkpoint > 0) {
113 const Pair* pair = exploration_stack_.back().get();
114 if (pair->graph_state->system_state_) {
115 mcapi::get().restore_state(pair->graph_state->system_state_);
120 /* Restore the initial state */
121 mcapi::get().restore_initial_state();
123 /* Traverse the stack from the initial state and re-execute the transitions */
125 for (std::shared_ptr<Pair> const& pair : exploration_stack_) {
126 if (pair == exploration_stack_.back())
129 std::shared_ptr<State> state = pair->graph_state;
131 if (pair->exploration_started) {
132 int req_num = state->transition_.argument_;
133 const s_smx_simcall* saved_req = &state->executed_req_;
135 smx_simcall_t req = nullptr;
137 /* because we got a copy of the executed request, we have to fetch the
138 real one, pointed by the request field of the issuer process */
139 const smx_actor_t issuer = mcapi::get().simcall_get_issuer(saved_req);
140 req = &issuer->simcall_;
142 /* Debug information */
143 XBT_DEBUG("Replay (depth = %d) : %s (%p)", depth,
144 mcapi::get().request_to_string(req, req_num, simgrid::mc::RequestType::simix).c_str(), state.get());
146 mcapi::get().execute(state->transition_);
149 /* Update statistics */
150 visited_pairs_count_++;
151 mcapi::get().mc_inc_executed_trans();
155 XBT_DEBUG("**** End Replay ****");
159 * @brief Checks whether a given pair has already been visited by the algorithm.
161 int LivenessChecker::insert_visited_pair(std::shared_ptr<VisitedPair> visited_pair, simgrid::mc::Pair* pair)
163 if (_sg_mc_max_visited_states == 0)
166 if (visited_pair == nullptr)
168 std::make_shared<VisitedPair>(pair->num, pair->automaton_state, pair->atomic_propositions, pair->graph_state);
170 auto range = boost::range::equal_range(visited_pairs_, visited_pair.get(), mcapi::get().compare_pair());
172 for (auto i = range.first; i != range.second; ++i) {
173 const VisitedPair* pair_test = i->get();
174 if (mcapi::get().automaton_state_compare(pair_test->automaton_state, visited_pair->automaton_state) != 0 ||
175 *(pair_test->atomic_propositions) != *(visited_pair->atomic_propositions) ||
176 not mcapi::get().snapshot_equal(pair_test->graph_state->system_state_.get(), visited_pair->graph_state->system_state_.get()))
178 if (pair_test->other_num == -1)
179 visited_pair->other_num = pair_test->num;
181 visited_pair->other_num = pair_test->other_num;
182 if (dot_output == nullptr)
183 XBT_DEBUG("Pair %d already visited ! (equal to pair %d)", visited_pair->num, pair_test->num);
185 XBT_DEBUG("Pair %d already visited ! (equal to pair %d (pair %d in dot_output))",
186 visited_pair->num, pair_test->num, visited_pair->other_num);
187 (*i) = std::move(visited_pair);
188 return (*i)->other_num;
191 visited_pairs_.insert(range.first, std::move(visited_pair));
192 this->purge_visited_pairs();
196 void LivenessChecker::purge_visited_pairs()
198 if (_sg_mc_max_visited_states != 0 && visited_pairs_.size() > (std::size_t)_sg_mc_max_visited_states) {
199 // Remove the oldest entry with a linear search:
200 visited_pairs_.erase(
201 boost::min_element(visited_pairs_, [](std::shared_ptr<VisitedPair> const a,
202 std::shared_ptr<VisitedPair> const& b) { return a->num < b->num; }));
206 LivenessChecker::LivenessChecker() : Checker()
210 RecordTrace LivenessChecker::get_record_trace() // override
213 for (std::shared_ptr<Pair> const& pair : exploration_stack_)
214 res.push_back(pair->graph_state->get_transition());
218 void LivenessChecker::log_state() // override
220 XBT_INFO("Expanded pairs = %lu", expanded_pairs_count_);
221 XBT_INFO("Visited pairs = %lu", visited_pairs_count_);
222 XBT_INFO("Executed transitions = %lu", mcapi::get().mc_get_executed_trans());
225 void LivenessChecker::show_acceptance_cycle(std::size_t depth)
227 XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
228 XBT_INFO("| ACCEPTANCE CYCLE |");
229 XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
230 XBT_INFO("Counter-example that violates formula:");
231 for (auto const& s : this->get_textual_trace())
232 XBT_INFO(" %s", s.c_str());
233 mcapi::get().dump_record_path();
234 mcapi::get().log_state();
235 XBT_INFO("Counter-example depth: %zu", depth);
238 std::vector<std::string> LivenessChecker::get_textual_trace() // override
240 std::vector<std::string> trace;
241 for (std::shared_ptr<Pair> const& pair : exploration_stack_) {
242 int req_num = pair->graph_state->transition_.argument_;
243 smx_simcall_t req = &pair->graph_state->executed_req_;
244 if (req->call_ != simix::Simcall::NONE)
245 trace.push_back(mcapi::get().request_to_string(req, req_num, RequestType::executed));
250 std::shared_ptr<Pair> LivenessChecker::create_pair(const Pair* current_pair, xbt_automaton_state_t state,
251 std::shared_ptr<const std::vector<int>> propositions)
253 ++expanded_pairs_count_;
254 ++expanded_states_count_;
255 auto next_pair = std::make_shared<Pair>(expanded_pairs_count_);
256 next_pair->automaton_state = state;
257 next_pair->graph_state = std::make_shared<State>(expanded_states_count_);
258 next_pair->atomic_propositions = std::move(propositions);
260 next_pair->depth = current_pair->depth + 1;
262 next_pair->depth = 1;
263 /* Get enabled actors and insert them in the interleave set of the next graph_state */
264 auto actors = mcapi::get().get_actors();
265 for (auto& actor : actors)
266 if (mcapi::get().actor_is_enabled(actor.copy.get_buffer()->get_pid()))
267 next_pair->graph_state->add_interleaving_set(actor.copy.get_buffer());
268 next_pair->requests = next_pair->graph_state->interleave_size();
269 /* FIXME : get search_cycle value for each accepting state */
270 if (next_pair->automaton_state->type == 1 || (current_pair && current_pair->search_cycle))
271 next_pair->search_cycle = true;
273 next_pair->search_cycle = false;
277 void LivenessChecker::backtrack()
279 /* Traverse the stack backwards until a pair with a non empty interleave
280 set is found, deleting all the pairs that have it empty in the way. */
281 while (not exploration_stack_.empty()) {
282 std::shared_ptr<simgrid::mc::Pair> current_pair = exploration_stack_.back();
283 exploration_stack_.pop_back();
284 if (current_pair->requests > 0) {
285 /* We found a backtracking point */
286 XBT_DEBUG("Backtracking to depth %d", current_pair->depth);
287 exploration_stack_.push_back(std::move(current_pair));
289 XBT_DEBUG("Backtracking done");
292 XBT_DEBUG("Delete pair %d at depth %d", current_pair->num, current_pair->depth);
293 if (current_pair->automaton_state->type == 1)
294 this->remove_acceptance_pair(current_pair->num);
299 void LivenessChecker::run()
301 XBT_INFO("Check the liveness property %s", _sg_mc_property_file.get().c_str());
302 mcapi::get().automaton_load(_sg_mc_property_file.get().c_str());
304 XBT_DEBUG("Starting the liveness algorithm");
305 mcapi::get().session_initialize();
308 this->previous_pair_ = 0;
310 std::shared_ptr<const std::vector<int>> propos = this->get_proposition_values();
312 // For each initial state of the property automaton, push a
313 // (application_state, automaton_state) pair to the exploration stack:
314 auto automaton_stack = mcapi::get().get_automaton_state();
315 for (auto* automaton_state : automaton_stack) {
316 if (automaton_state->type == -1)
317 exploration_stack_.push_back(this->create_pair(nullptr, automaton_state, propos));
320 /* Actually run the double DFS search for counter-examples */
321 while (not exploration_stack_.empty()) {
322 std::shared_ptr<Pair> current_pair = exploration_stack_.back();
324 /* Update current state in buchi automaton */
325 mcapi::get().set_property_automaton(current_pair->automaton_state);
328 "********************* ( Depth = %d, search_cycle = %d, interleave size = %zu, pair_num = %d, requests = %d)",
329 current_pair->depth, current_pair->search_cycle, current_pair->graph_state->interleave_size(),
330 current_pair->num, current_pair->requests);
332 if (current_pair->requests == 0) {
337 std::shared_ptr<VisitedPair> reached_pair;
338 if (current_pair->automaton_state->type == 1 && not current_pair->exploration_started) {
339 reached_pair = this->insert_acceptance_pair(current_pair.get());
340 if (reached_pair == nullptr) {
341 this->show_acceptance_cycle(current_pair->depth);
342 throw LivenessError();
346 /* Pair already visited ? stop the exploration on the current path */
347 if (not current_pair->exploration_started) {
348 int visited_num = this->insert_visited_pair(reached_pair, current_pair.get());
349 if (visited_num != -1) {
350 if (dot_output != nullptr) {
351 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", this->previous_pair_, visited_num,
352 this->previous_request_.c_str());
355 XBT_DEBUG("Pair already visited (equal to pair %d), exploration on the current path stopped.", visited_num);
356 current_pair->requests = 0;
362 smx_simcall_t req = mcapi::get().mc_state_choose_request(current_pair->graph_state.get());
363 int req_num = current_pair->graph_state->transition_.argument_;
365 if (dot_output != nullptr) {
366 if (this->previous_pair_ != 0 && this->previous_pair_ != current_pair->num) {
367 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", this->previous_pair_, current_pair->num,
368 this->previous_request_.c_str());
369 this->previous_request_.clear();
371 this->previous_pair_ = current_pair->num;
372 this->previous_request_ = mcapi::get().request_get_dot_output(req, req_num);
373 if (current_pair->search_cycle)
374 fprintf(dot_output, "%d [shape=doublecircle];\n", current_pair->num);
378 XBT_DEBUG("Execute: %s", mcapi::get().request_to_string(req, req_num, RequestType::simix).c_str());
381 mcapi::get().mc_inc_executed_trans();
383 if (not current_pair->exploration_started)
384 visited_pairs_count_++;
386 /* Answer the request */
387 mcapi::get().handle_simcall(current_pair->graph_state->transition_);
389 /* Wait for requests (schedules processes) */
390 mcapi::get().mc_wait_for_requests();
392 current_pair->requests--;
393 current_pair->exploration_started = true;
395 /* Get values of atomic propositions (variables used in the property formula) */
396 std::shared_ptr<const std::vector<int>> prop_values = this->get_proposition_values();
398 // For each enabled transition in the property automaton, push a
399 // (application_state, automaton_state) pair to the exploration stack:
400 for (int i = mcapi::get().get_dynar_length(current_pair->automaton_state->out) - 1; i >= 0; i--) {
401 auto transition_succ_label = mcapi::get().get_automaton_transition_label(current_pair->automaton_state->out, i);
402 auto transition_succ_dst = mcapi::get().get_automaton_transition_dst(current_pair->automaton_state->out, i);
403 if (evaluate_label(transition_succ_label, *prop_values))
404 exploration_stack_.push_back(this->create_pair(current_pair.get(), transition_succ_dst, prop_values));
408 XBT_INFO("No property violation found.");
409 mcapi::get().log_state();
412 Checker* createLivenessChecker()
414 return new LivenessChecker();
418 } // namespace simgrid