X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/b519c710a179e22b19c6d21721c6c0dfd13e65ce..3b52cd5802625263b86a39f7c25defbc32b0fe7d:/src/mc/explo/DFSExplorer.cpp diff --git a/src/mc/explo/DFSExplorer.cpp b/src/mc/explo/DFSExplorer.cpp index 8f1fe11789..3a99ca58e1 100644 --- a/src/mc/explo/DFSExplorer.cpp +++ b/src/mc/explo/DFSExplorer.cpp @@ -4,13 +4,16 @@ * under the terms of the license (GNU LGPL) which comes with this package. */ #include "src/mc/explo/DFSExplorer.hpp" -#include "src/mc/VisitedState.hpp" #include "src/mc/mc_config.hpp" #include "src/mc/mc_exit.hpp" #include "src/mc/mc_private.hpp" #include "src/mc/mc_record.hpp" #include "src/mc/transition/Transition.hpp" +#if SIMGRID_HAVE_STATEFUL_MC +#include "src/mc/VisitedState.hpp" +#endif + #include "src/xbt/mmalloc/mmprivate.h" #include "xbt/log.h" #include "xbt/string.hpp" @@ -41,6 +44,7 @@ xbt::signal DFSExplorer::on_log_state_signal; void DFSExplorer::check_non_termination(const State* current_state) { +#if SIMGRID_HAVE_STATEFUL_MC for (auto const& state : stack_) { if (state->get_system_state()->equals_to(*current_state->get_system_state(), *get_remote_app().get_remote_process_memory())) { @@ -56,9 +60,10 @@ void DFSExplorer::check_non_termination(const State* current_state) get_record_trace().to_string().c_str()); log_state(); - throw TerminationError(); + throw McError(ExitStatus::NON_TERMINATION); } } +#endif } RecordTrace DFSExplorer::get_record_trace() // override @@ -76,21 +81,20 @@ std::vector DFSExplorer::get_textual_trace() // override for (auto const& transition : stack_.back()->get_recipe()) { trace.push_back(xbt::string_printf("%ld: %s", transition->aid_, transition->to_string().c_str())); } - trace.push_back(xbt::string_printf("%ld: %s", stack_.back()->get_transition()->aid_, - stack_.back()->get_transition()->to_string().c_str())); + if (const auto* trans = stack_.back()->get_transition(); trans != nullptr) + trace.push_back(xbt::string_printf("%ld: %s", trans->aid_, trans->to_string().c_str())); return trace; } void DFSExplorer::restore_stack(std::shared_ptr state) { - - stack_ = std::list>(); - std::shared_ptr current_state(state); - stack_.push_front(std::shared_ptr(current_state)); + stack_.clear(); + auto current_state = state; + stack_.emplace_front(current_state); // condition corresponds to reaching initial state while (current_state->get_parent_state() != nullptr) { current_state = current_state->get_parent_state(); - stack_.push_front(std::shared_ptr(current_state)); + stack_.emplace_front(current_state); } XBT_DEBUG("Replaced stack by %s", get_record_trace().to_string().c_str()); } @@ -114,7 +118,7 @@ void DFSExplorer::run() while (not stack_.empty()) { /* Get current state */ - std::shared_ptr state(stack_.back()); + auto state = stack_.back(); XBT_DEBUG("**************************************************"); XBT_DEBUG("Exploration depth=%zu (state:#%ld; %zu interleaves todo)", stack_.size(), state->get_num(), @@ -134,6 +138,7 @@ void DFSExplorer::run() continue; } +#if SIMGRID_HAVE_STATEFUL_MC // Backtrack if we are revisiting a state we saw previously while applying state-equality reduction if (visited_state_ != nullptr) { XBT_DEBUG("State already visited (equal to state %ld), exploration stopped on this path.", @@ -143,9 +148,10 @@ void DFSExplorer::run() this->backtrack(); continue; } +#endif // Search for the next transition - // next_transition returns a pair in case we want to consider multiple state (eg. during backtrack) + // next_transition returns a pair in case we want to consider multiple state (eg. during backtrack) auto [next, _] = state->next_transition_guided(); if (next < 0) { // If there is no more transition in the current state, backtrack. @@ -178,7 +184,7 @@ void DFSExplorer::run() state->get_transition()->to_string().c_str(), stack_.size(), state->get_num(), state->count_todo()); /* Create the new expanded state (copy the state of MCed into our MCer data) */ - std::shared_ptr next_state = std::make_shared(get_remote_app(), state); + auto next_state = std::make_shared(get_remote_app(), state); on_state_creation_signal(next_state.get(), get_remote_app()); /* Sleep set procedure: @@ -195,10 +201,10 @@ void DFSExplorer::run() * If the process is not enabled at this point, then add every enabled process to the interleave */ if (reduction_mode_ == ReductionMode::dpor) { aid_t issuer_id = state->get_transition()->aid_; - stack_t tmp_stack = std::list(stack_); + stack_t tmp_stack = stack_; while (not tmp_stack.empty()) { - State* prev_state = tmp_stack.back().get(); - if (state->get_transition()->aid_ == prev_state->get_transition()->aid_) { + if (const State* prev_state = tmp_stack.back().get(); + state->get_transition()->aid_ == prev_state->get_transition()->aid_) { XBT_DEBUG("Simcall >>%s<< and >>%s<< with same issuer %ld", state->get_transition()->to_string().c_str(), prev_state->get_transition()->to_string().c_str(), issuer_id); tmp_stack.pop_back(); @@ -211,7 +217,7 @@ void DFSExplorer::run() if (prev_state->is_actor_enabled(issuer_id)) { if (not prev_state->is_actor_done(issuer_id)) { prev_state->consider_one(issuer_id); - opened_states_.push(std::shared_ptr(tmp_stack.back())); + opened_states_.emplace_back(tmp_stack.back()); } else XBT_DEBUG("Actor %ld is already in done set: no need to explore it again", issuer_id); } else { @@ -220,7 +226,7 @@ void DFSExplorer::run() issuer_id); // If we ended up marking at least a transition, explore it at some point if (prev_state->consider_all() > 0) - opened_states_.push(std::shared_ptr(tmp_stack.back())); + opened_states_.emplace_back(tmp_stack.back()); } break; } else { @@ -235,16 +241,18 @@ void DFSExplorer::run() // Before leaving that state, if the transition we just took can be taken multiple times, we // need to give it to the opened states if (stack_.back()->count_todo_multiples() > 0) - opened_states_.push(std::shared_ptr(stack_.back())); + opened_states_.emplace_back(stack_.back()); if (_sg_mc_termination) this->check_non_termination(next_state.get()); +#if SIMGRID_HAVE_STATEFUL_MC /* Check whether we already explored next_state in the past (but only if interested in state-equality reduction) */ if (_sg_mc_max_visited_states > 0) visited_state_ = visited_states_.addVisitedState(next_state->get_num(), next_state.get(), get_remote_app()); +#endif - stack_.push_back(std::move(next_state)); + stack_.emplace_back(std::move(next_state)); /* If this is a new state (or if we don't care about state-equality reduction) */ if (visited_state_ == nullptr) { @@ -257,14 +265,52 @@ void DFSExplorer::run() dot_output("\"%ld\" -> \"%ld\" [%s];\n", state->get_num(), stack_.back()->get_num(), state->get_transition()->dot_string().c_str()); - } else +#if SIMGRID_HAVE_STATEFUL_MC + } else { dot_output("\"%ld\" -> \"%ld\" [%s];\n", state->get_num(), visited_state_->original_num_ == -1 ? visited_state_->num_ : visited_state_->original_num_, state->get_transition()->dot_string().c_str()); +#endif + } } log_state(); } +std::shared_ptr DFSExplorer::best_opened_state() +{ + int best_prio = 0; // cache the value for the best priority found so far (initialized to silence gcc) + auto best = end(opened_states_); // iterator to the state to explore having the best priority + auto valid = begin(opened_states_); // iterator marking the limit between states still to explore, and already + // explored ones + + // Keep only still non-explored states (aid != -1), and record the one with the best (greater) priority. + for (auto current = begin(opened_states_); current != end(opened_states_); ++current) { + auto [aid, prio] = (*current)->next_transition_guided(); + if (aid == -1) + continue; + if (valid != current) + *valid = std::move(*current); + if (best == end(opened_states_) || prio > best_prio) { + best_prio = prio; + best = valid; + } + ++valid; + } + + std::shared_ptr best_state; + if (best < valid) { + // There are non-explored states, and one of them has the best priority. Remove it from opened_states_ before + // returning. + best_state = std::move(*best); + --valid; + if (best != valid) + *best = std::move(*valid); + } + opened_states_.erase(valid, end(opened_states_)); + + return best_state; +} + void DFSExplorer::backtrack() { XBT_VERB("Backtracking from %s", get_record_trace().to_string().c_str()); @@ -273,27 +319,21 @@ void DFSExplorer::backtrack() on_backtracking_signal(get_remote_app()); get_remote_app().check_deadlock(); + // Take the point with smallest distance + auto backtracking_point = best_opened_state(); + // if no backtracking point, then set the stack_ to empty so we can end the exploration - if (opened_states_.empty()) { + if (not backtracking_point) { XBT_DEBUG("No more opened point of exploration, the search will end"); - stack_ = std::list>(); + stack_.clear(); return; } - std::shared_ptr backtracking_point = opened_states_.top(); // Take the point with smallest distance - opened_states_.pop(); - - // if the smallest distance corresponded to no enable actor, remove this and let the - // exploration ask again for a backtrack - if (backtracking_point->next_transition_guided().first == -1) { - XBT_DEBUG("Best backtracking candidates has already been explored. Let's backtrack again"); - this->backtrack(); - return; - } - - // We found a real backtracking point, let's go to it + // We found a backtracking point, let's go to it backtrack_count_++; XBT_DEBUG("Backtracking to state#%ld", backtracking_point->get_num()); + +#if SIMGRID_HAVE_STATEFUL_MC /* If asked to rollback on a state that has a snapshot, restore it */ if (const auto* system_state = backtracking_point->get_system_state()) { system_state->restore(*get_remote_app().get_remote_process_memory()); @@ -301,6 +341,7 @@ void DFSExplorer::backtrack() this->restore_stack(backtracking_point); return; } +#endif /* if no snapshot, we need to restore the initial state and replay the transitions */ get_remote_app().restore_initial_state(); @@ -336,7 +377,7 @@ DFSExplorer::DFSExplorer(const std::vector& args, bool with_dpor, bool ne XBT_DEBUG("**************************************************"); - stack_.push_back(std::move(initial_state)); + stack_.emplace_back(std::move(initial_state)); /* Get an enabled actor and insert it in the interleave set of the initial state */ XBT_DEBUG("Initial state. %lu actors to consider", stack_.back()->get_actor_count()); @@ -346,7 +387,7 @@ DFSExplorer::DFSExplorer(const std::vector& args, bool with_dpor, bool ne stack_.back()->consider_all(); } if (stack_.back()->count_todo_multiples() > 1) - opened_states_.push(std::shared_ptr(stack_.back())); + opened_states_.emplace_back(stack_.back()); } Exploration* create_dfs_exploration(const std::vector& args, bool with_dpor)