1 /* Copyright (c) 2011-2015. 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 <xbt/automaton.h>
13 #include <xbt/dynar.h>
16 #include <xbt/sysdep.h>
18 #include "src/mc/mc_request.h"
19 #include "src/mc/mc_liveness.h"
20 #include "src/mc/mc_private.h"
21 #include "src/mc/mc_record.h"
22 #include "src/mc/mc_smx.h"
23 #include "src/mc/Client.hpp"
24 #include "src/mc/mc_private.h"
25 #include "src/mc/mc_replay.h"
26 #include "src/mc/mc_safety.h"
27 #include "src/mc/mc_exit.h"
29 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_liveness, mc,
30 "Logging specific to algorithms for liveness properties verification");
32 /********* Global variables *********/
34 xbt_dynar_t acceptance_pairs;
36 /********* Static functions *********/
41 static xbt_dynar_t visited_pairs;
43 Pair::Pair() : num(++mc_stats->expanded_pairs),
44 visited_pair_removed(_sg_mc_visited > 0 ? 0 : 1)
48 if (this->visited_pair_removed)
49 MC_state_delete(this->graph_state, 1);
52 static void show_stack_liveness(xbt_fifo_t stack)
55 simgrid::mc::Pair* pair;
58 char *req_str = nullptr;
60 for (item = xbt_fifo_get_last_item(stack);
61 item; item = xbt_fifo_get_prev_item(item)) {
62 pair = (simgrid::mc::Pair*) xbt_fifo_get_item_content(item);
63 req = MC_state_get_executed_request(pair->graph_state, &value);
64 if (req && req->call != SIMCALL_NONE) {
65 req_str = simgrid::mc::request_to_string(req, value, simgrid::mc::RequestType::executed);
66 XBT_INFO("%s", req_str);
72 static void dump_stack_liveness(xbt_fifo_t stack)
74 simgrid::mc::Pair* pair;
75 while ((pair = (simgrid::mc::Pair*) xbt_fifo_pop(stack)) != nullptr)
79 static simgrid::xbt::unique_ptr<s_xbt_dynar_t> get_atomic_propositions_values()
81 unsigned int cursor = 0;
82 xbt_automaton_propositional_symbol_t ps = nullptr;
83 simgrid::xbt::unique_ptr<s_xbt_dynar_t> values = simgrid::xbt::unique_ptr<s_xbt_dynar_t>(xbt_dynar_new(sizeof(int), nullptr));
84 xbt_dynar_foreach(simgrid::mc::property_automaton->propositional_symbols, cursor, ps) {
85 int res = xbt_automaton_propositional_symbol_evaluate(ps);
86 xbt_dynar_push_as(values.get(), int, res);
88 return std::move(values);
91 static int snapshot_compare(simgrid::mc::VisitedPair* state1, simgrid::mc::VisitedPair* state2)
93 simgrid::mc::Snapshot* s1 = state1->graph_state->system_state;
94 simgrid::mc::Snapshot* s2 = state2->graph_state->system_state;
95 int num1 = state1->num;
96 int num2 = state2->num;
97 return snapshot_compare(num1, s1, num2, s2);
100 static simgrid::mc::VisitedPair* is_reached_acceptance_pair(simgrid::mc::Pair* pair)
102 simgrid::mc::VisitedPair* new_pair = new VisitedPair(
103 pair->num, pair->automaton_state, pair->atomic_propositions.get(),
105 new_pair->acceptance_pair = 1;
107 if (xbt_dynar_is_empty(acceptance_pairs))
108 xbt_dynar_push(acceptance_pairs, &new_pair);
111 int min = -1, max = -1, index;
113 simgrid::mc::VisitedPair* pair_test;
116 index = simgrid::mc::get_search_interval(
117 (simgrid::mc::VisitedPair**) xbt_dynar_get_ptr(acceptance_pairs, 0),
118 xbt_dynar_length(acceptance_pairs),
119 new_pair, &min, &max);
121 if (min != -1 && max != -1) { // Acceptance pair with same number of processes and same heap bytes used exists
124 if(pair->search_cycle == 1){
125 while (cursor <= max) {
126 pair_test = (simgrid::mc::VisitedPair*) xbt_dynar_get_as(acceptance_pairs, cursor, simgrid::mc::VisitedPair*);
127 if (xbt_automaton_state_compare(pair_test->automaton_state, new_pair->automaton_state) == 0) {
128 if (xbt_automaton_propositional_symbols_compare_value(
129 pair_test->atomic_propositions.get(),
130 new_pair->atomic_propositions.get()) == 0) {
131 if (snapshot_compare(pair_test, new_pair) == 0) {
132 XBT_INFO("Pair %d already reached (equal to pair %d) !", new_pair->num, pair_test->num);
133 xbt_fifo_shift(mc_stack);
134 if (dot_output != nullptr)
135 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", initial_global_state->prev_pair, pair_test->num, initial_global_state->prev_req);
143 xbt_dynar_insert_at(acceptance_pairs, min, &new_pair);
145 pair_test = (simgrid::mc::VisitedPair*) xbt_dynar_get_as(acceptance_pairs, index, simgrid::mc::VisitedPair*);
146 if (pair_test->nb_processes < new_pair->nb_processes)
147 xbt_dynar_insert_at(acceptance_pairs, index + 1, &new_pair);
148 else if (pair_test->heap_bytes_used < new_pair->heap_bytes_used)
149 xbt_dynar_insert_at(acceptance_pairs, index + 1, &new_pair);
151 xbt_dynar_insert_at(acceptance_pairs, index, &new_pair);
157 static void remove_acceptance_pair(int pair_num)
159 unsigned int cursor = 0;
160 simgrid::mc::VisitedPair* pair_test = nullptr;
163 xbt_dynar_foreach(acceptance_pairs, cursor, pair_test)
164 if (pair_test->num == pair_num) {
169 if(pair_found == 1) {
170 xbt_dynar_remove_at(acceptance_pairs, cursor, &pair_test);
172 pair_test->acceptance_removed = 1;
174 if (_sg_mc_visited == 0 || pair_test->visited_removed == 1)
181 static int MC_automaton_evaluate_label(xbt_automaton_exp_label_t l,
182 xbt_dynar_t atomic_propositions_values)
187 int left_res = MC_automaton_evaluate_label(l->u.or_and.left_exp, atomic_propositions_values);
188 int right_res = MC_automaton_evaluate_label(l->u.or_and.right_exp, atomic_propositions_values);
189 return (left_res || right_res);
192 int left_res = MC_automaton_evaluate_label(l->u.or_and.left_exp, atomic_propositions_values);
193 int right_res = MC_automaton_evaluate_label(l->u.or_and.right_exp, atomic_propositions_values);
194 return (left_res && right_res);
197 int res = MC_automaton_evaluate_label(l->u.exp_not, atomic_propositions_values);
201 unsigned int cursor = 0;
202 xbt_automaton_propositional_symbol_t p = nullptr;
203 xbt_dynar_foreach(simgrid::mc::property_automaton->propositional_symbols, cursor, p) {
204 if (std::strcmp(xbt_automaton_propositional_symbol_get_name(p), l->u.predicat) == 0)
205 return (int) xbt_dynar_get_as(atomic_propositions_values, cursor, int);
216 static void MC_pre_modelcheck_liveness(void)
218 simgrid::mc::Pair* initial_pair = nullptr;
219 mc_model_checker->wait_for_requests();
220 acceptance_pairs = xbt_dynar_new(sizeof(simgrid::mc::VisitedPair*), nullptr);
221 if(_sg_mc_visited > 0)
222 simgrid::mc::visited_pairs = xbt_dynar_new(sizeof(simgrid::mc::VisitedPair*), nullptr);
224 initial_global_state->snapshot = simgrid::mc::take_snapshot(0);
225 initial_global_state->prev_pair = 0;
227 unsigned int cursor = 0;
228 xbt_automaton_state_t automaton_state;
230 xbt_dynar_foreach(simgrid::mc::property_automaton->states, cursor, automaton_state) {
231 if (automaton_state->type == -1) { /* Initial automaton state */
233 initial_pair = new Pair();
234 initial_pair->automaton_state = automaton_state;
235 initial_pair->graph_state = MC_state_new();
236 initial_pair->atomic_propositions = get_atomic_propositions_values();
237 initial_pair->depth = 1;
239 /* Get enabled processes and insert them in the interleave set of the graph_state */
240 for (auto& p : mc_model_checker->process().simix_processes())
241 if (simgrid::mc::process_is_enabled(&p.copy))
242 MC_state_interleave_process(initial_pair->graph_state, &p.copy);
244 initial_pair->requests = MC_state_interleave_size(initial_pair->graph_state);
245 initial_pair->search_cycle = 0;
247 xbt_fifo_unshift(mc_stack, initial_pair);
252 static void MC_replay_liveness(xbt_fifo_t stack)
254 xbt_fifo_item_t item;
255 simgrid::mc::Pair* pair = nullptr;
256 mc_state_t state = nullptr;
257 smx_simcall_t req = nullptr, saved_req = NULL;
258 int value, depth = 1;
261 XBT_DEBUG("**** Begin Replay ****");
263 /* Intermediate backtracking */
264 if(_sg_mc_checkpoint > 0) {
265 item = xbt_fifo_get_first_item(stack);
266 pair = (simgrid::mc::Pair*) xbt_fifo_get_item_content(item);
267 if(pair->graph_state->system_state){
268 simgrid::mc::restore_snapshot(pair->graph_state->system_state);
273 /* Restore the initial state */
274 simgrid::mc::restore_snapshot(initial_global_state->snapshot);
276 /* Traverse the stack from the initial state and re-execute the transitions */
277 for (item = xbt_fifo_get_last_item(stack);
278 item != xbt_fifo_get_first_item(stack);
279 item = xbt_fifo_get_prev_item(item)) {
281 pair = (simgrid::mc::Pair*) xbt_fifo_get_item_content(item);
283 state = (mc_state_t) pair->graph_state;
285 if (pair->exploration_started) {
287 saved_req = MC_state_get_executed_request(state, &value);
289 if (saved_req != nullptr) {
290 /* because we got a copy of the executed request, we have to fetch the
291 real one, pointed by the request field of the issuer process */
292 const smx_process_t issuer = MC_smx_simcall_get_issuer(saved_req);
293 req = &issuer->simcall;
295 /* Debug information */
296 if (XBT_LOG_ISENABLED(mc_liveness, xbt_log_priority_debug)) {
297 req_str = simgrid::mc::request_to_string(req, value, simgrid::mc::RequestType::simix);
298 XBT_DEBUG("Replay (depth = %d) : %s (%p)", depth, req_str, state);
304 simgrid::mc::handle_simcall(req, value);
305 mc_model_checker->wait_for_requests();
308 /* Update statistics */
309 mc_stats->visited_pairs++;
310 mc_stats->executed_transitions++;
316 XBT_DEBUG("**** End Replay ****");
320 * \brief Checks whether a given pair has already been visited by the algorithm.
323 int is_visited_pair(simgrid::mc::VisitedPair* visited_pair, simgrid::mc::Pair* pair)
325 if (_sg_mc_visited == 0)
328 simgrid::mc::VisitedPair* new_visited_pair = nullptr;
329 if (visited_pair == nullptr)
330 new_visited_pair = new simgrid::mc::VisitedPair(
331 pair->num, pair->automaton_state, pair->atomic_propositions.get(),
334 new_visited_pair = visited_pair;
336 if (xbt_dynar_is_empty(visited_pairs)) {
337 xbt_dynar_push(visited_pairs, &new_visited_pair);
341 int min = -1, max = -1, index;
343 simgrid::mc::VisitedPair* pair_test;
346 index = get_search_interval(
347 (simgrid::mc::VisitedPair**) xbt_dynar_get_ptr(visited_pairs, 0),
348 xbt_dynar_length(visited_pairs), new_visited_pair, &min, &max);
350 if (min != -1 && max != -1) { // Visited pair with same number of processes and same heap bytes used exists
352 while (cursor <= max) {
353 pair_test = (simgrid::mc::VisitedPair*) xbt_dynar_get_as(visited_pairs, cursor, simgrid::mc::VisitedPair*);
354 if (xbt_automaton_state_compare(pair_test->automaton_state, new_visited_pair->automaton_state) == 0) {
355 if (xbt_automaton_propositional_symbols_compare_value(
356 pair_test->atomic_propositions.get(),
357 new_visited_pair->atomic_propositions.get()) == 0) {
358 if (snapshot_compare(pair_test, new_visited_pair) == 0) {
359 if (pair_test->other_num == -1)
360 new_visited_pair->other_num = pair_test->num;
362 new_visited_pair->other_num = pair_test->other_num;
363 if (dot_output == nullptr)
364 XBT_DEBUG("Pair %d already visited ! (equal to pair %d)", new_visited_pair->num, pair_test->num);
366 XBT_DEBUG("Pair %d already visited ! (equal to pair %d (pair %d in dot_output))", new_visited_pair->num, pair_test->num, new_visited_pair->other_num);
367 xbt_dynar_remove_at(visited_pairs, cursor, &pair_test);
368 xbt_dynar_insert_at(visited_pairs, cursor, &new_visited_pair);
369 pair_test->visited_removed = 1;
370 if (!pair_test->acceptance_pair
371 || pair_test->acceptance_removed == 1)
373 return new_visited_pair->other_num;
379 xbt_dynar_insert_at(visited_pairs, min, &new_visited_pair);
381 pair_test = (simgrid::mc::VisitedPair*) xbt_dynar_get_as(visited_pairs, index, simgrid::mc::VisitedPair*);
382 if (pair_test->nb_processes < new_visited_pair->nb_processes)
383 xbt_dynar_insert_at(visited_pairs, index + 1, &new_visited_pair);
384 else if (pair_test->heap_bytes_used < new_visited_pair->heap_bytes_used)
385 xbt_dynar_insert_at(visited_pairs, index + 1, &new_visited_pair);
387 xbt_dynar_insert_at(visited_pairs, index, &new_visited_pair);
390 if ((ssize_t) xbt_dynar_length(visited_pairs) > _sg_mc_visited) {
391 int min2 = mc_stats->expanded_pairs;
392 unsigned int cursor2 = 0;
393 unsigned int index2 = 0;
394 xbt_dynar_foreach(visited_pairs, cursor2, pair_test) {
395 if (!mc_model_checker->is_important_snapshot(*pair_test->graph_state->system_state)
396 && pair_test->num < min2) {
398 min2 = pair_test->num;
401 xbt_dynar_remove_at(visited_pairs, index2, &pair_test);
402 pair_test->visited_removed = 1;
403 if (!pair_test->acceptance_pair || pair_test->acceptance_removed)
409 static int MC_modelcheck_liveness_main(void)
411 simgrid::mc::Pair* current_pair = nullptr;
412 int value, res, visited_num = -1;
413 smx_simcall_t req = nullptr;
414 xbt_automaton_transition_t transition_succ = nullptr;
416 simgrid::mc::Pair* next_pair = nullptr;
417 simgrid::xbt::unique_ptr<s_xbt_dynar_t> prop_values;
418 simgrid::mc::VisitedPair* reached_pair = nullptr;
420 while(xbt_fifo_size(mc_stack) > 0){
422 /* Get current pair */
423 current_pair = (simgrid::mc::Pair*) xbt_fifo_get_item_content(xbt_fifo_get_first_item(mc_stack));
425 /* Update current state in buchi automaton */
426 simgrid::mc::property_automaton->current_state = current_pair->automaton_state;
428 XBT_DEBUG("********************* ( Depth = %d, search_cycle = %d, interleave size = %d, pair_num = %d, requests = %d)",
429 current_pair->depth, current_pair->search_cycle,
430 MC_state_interleave_size(current_pair->graph_state), current_pair->num,
431 current_pair->requests);
433 if (current_pair->requests > 0) {
435 if (current_pair->automaton_state->type == 1 && current_pair->exploration_started == 0) {
436 /* If new acceptance pair, return new pair */
437 if ((reached_pair = is_reached_acceptance_pair(current_pair)) == nullptr) {
438 int counter_example_depth = current_pair->depth;
439 XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
440 XBT_INFO("| ACCEPTANCE CYCLE |");
441 XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
442 XBT_INFO("Counter-example that violates formula :");
443 MC_record_dump_path(mc_stack);
444 simgrid::mc::show_stack_liveness(mc_stack);
445 simgrid::mc::dump_stack_liveness(mc_stack);
446 MC_print_statistics(mc_stats);
447 XBT_INFO("Counter-example depth : %d", counter_example_depth);
448 return SIMGRID_MC_EXIT_LIVENESS;
452 /* Pair already visited ? stop the exploration on the current path */
453 if ((current_pair->exploration_started == 0)
454 && (visited_num = simgrid::mc::is_visited_pair(
455 reached_pair, current_pair)) != -1) {
457 if (dot_output != nullptr){
458 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", initial_global_state->prev_pair, visited_num, initial_global_state->prev_req);
462 XBT_DEBUG("Pair already visited (equal to pair %d), exploration on the current path stopped.", visited_num);
463 current_pair->requests = 0;
468 req = MC_state_get_request(current_pair->graph_state, &value);
470 if (dot_output != nullptr) {
471 if (initial_global_state->prev_pair != 0 && initial_global_state->prev_pair != current_pair->num) {
472 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", initial_global_state->prev_pair, current_pair->num, initial_global_state->prev_req);
473 xbt_free(initial_global_state->prev_req);
475 initial_global_state->prev_pair = current_pair->num;
476 initial_global_state->prev_req = simgrid::mc::request_get_dot_output(req, value);
477 if (current_pair->search_cycle)
478 fprintf(dot_output, "%d [shape=doublecircle];\n", current_pair->num);
482 char* req_str = simgrid::mc::request_to_string(req, value, simgrid::mc::RequestType::simix);
483 XBT_DEBUG("Execute: %s", req_str);
486 /* Set request as executed */
487 MC_state_set_executed_request(current_pair->graph_state, req, value);
489 /* Update mc_stats */
490 mc_stats->executed_transitions++;
491 if(current_pair->exploration_started == 0)
492 mc_stats->visited_pairs++;
494 /* Answer the request */
495 simgrid::mc::handle_simcall(req, value);
497 /* Wait for requests (schedules processes) */
498 mc_model_checker->wait_for_requests();
500 current_pair->requests--;
501 current_pair->exploration_started = 1;
503 /* Get values of atomic propositions (variables used in the property formula) */
504 prop_values = get_atomic_propositions_values();
506 /* Evaluate enabled/true transitions in automaton according to atomic propositions values and create new pairs */
507 cursor = xbt_dynar_length(current_pair->automaton_state->out) - 1;
508 while (cursor >= 0) {
509 transition_succ = (xbt_automaton_transition_t)xbt_dynar_get_as(current_pair->automaton_state->out, cursor, xbt_automaton_transition_t);
510 res = MC_automaton_evaluate_label(transition_succ->label, prop_values.get());
511 if (res == 1 || res == 2) { /* 1 = True transition (always enabled), 2 = enabled transition according to atomic prop values */
512 next_pair = new Pair();
513 next_pair->graph_state = MC_state_new();
514 next_pair->automaton_state = transition_succ->dst;
515 next_pair->atomic_propositions = get_atomic_propositions_values();
516 next_pair->depth = current_pair->depth + 1;
517 /* Get enabled processes and insert them in the interleave set of the next graph_state */
518 for (auto& p : mc_model_checker->process().simix_processes())
519 if (simgrid::mc::process_is_enabled(&p.copy))
520 MC_state_interleave_process(next_pair->graph_state, &p.copy);
522 next_pair->requests = MC_state_interleave_size(next_pair->graph_state);
524 /* FIXME : get search_cycle value for each acceptant state */
525 if (next_pair->automaton_state->type == 1 || current_pair->search_cycle)
526 next_pair->search_cycle = 1;
528 /* Add new pair to the exploration stack */
529 xbt_fifo_unshift(mc_stack, next_pair);
535 } /* End of visited_pair test */
540 if(visited_num == -1)
541 XBT_DEBUG("No more request to execute. Looking for backtracking point.");
545 /* Traverse the stack backwards until a pair with a non empty interleave
546 set is found, deleting all the pairs that have it empty in the way. */
547 while ((current_pair = (simgrid::mc::Pair*) xbt_fifo_shift(mc_stack)) != nullptr) {
548 if (current_pair->requests > 0) {
549 /* We found a backtracking point */
550 XBT_DEBUG("Backtracking to depth %d", current_pair->depth);
551 xbt_fifo_unshift(mc_stack, current_pair);
552 MC_replay_liveness(mc_stack);
553 XBT_DEBUG("Backtracking done");
557 XBT_DEBUG("Delete pair %d at depth %d", current_pair->num, current_pair->depth);
558 if (current_pair->automaton_state->type == 1)
559 remove_acceptance_pair(current_pair->num);
564 } /* End of if (current_pair->requests > 0) else ... */
566 } /* End of while(xbt_fifo_size(mc_stack) > 0) */
568 XBT_INFO("No property violation found.");
569 MC_print_statistics(mc_stats);
570 return SIMGRID_MC_EXIT_SUCCESS;
573 int modelcheck_liveness(void)
575 XBT_INFO("Check the liveness property %s", _sg_mc_property_file);
576 MC_automaton_load(_sg_mc_property_file);
577 mc_model_checker->wait_for_requests();
579 XBT_DEBUG("Starting the liveness algorithm");
582 /* Create exploration stack */
583 mc_stack = xbt_fifo_new();
585 /* Create the initial state */
586 initial_global_state = xbt_new0(s_mc_global_t, 1);
588 MC_pre_modelcheck_liveness();
589 int res = MC_modelcheck_liveness_main();
592 simgrid::mc::processes_time.clear();