X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/afb694bd672b9e44c91455cf4c3eb76c9e7b960a..86a552c797938ffe6db296e12b7043c3c7fdf14f:/src/mc/explo/DFSExplorer.cpp diff --git a/src/mc/explo/DFSExplorer.cpp b/src/mc/explo/DFSExplorer.cpp index 5903739f9e..3f44ee29bf 100644 --- a/src/mc/explo/DFSExplorer.cpp +++ b/src/mc/explo/DFSExplorer.cpp @@ -22,8 +22,10 @@ #include #include +#include #include #include +#include #include XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_dfs, mc, "DFS exploration algorithm of the model-checker"); @@ -69,21 +71,14 @@ void DFSExplorer::check_non_termination(const State* current_state) RecordTrace DFSExplorer::get_record_trace() // override { RecordTrace res; - for (auto const& transition : stack_.back()->get_recipe()) - res.push_back(transition); - res.push_back(stack_.back()->get_transition()); - return res; -} -std::vector DFSExplorer::get_textual_trace() // override -{ - std::vector trace; - 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())); - return trace; + if (const auto trans = stack_.back()->get_transition_out(); trans != nullptr) + res.push_back(trans.get()); + for (const auto* state = stack_.back().get(); state != nullptr; state = state->get_parent_state().get()) + if (state->get_transition_in() != nullptr) + res.push_front(state->get_transition_in().get()); + + return res; } void DFSExplorer::restore_stack(std::shared_ptr state) @@ -97,6 +92,15 @@ void DFSExplorer::restore_stack(std::shared_ptr state) stack_.emplace_front(current_state); } XBT_DEBUG("Replaced stack by %s", get_record_trace().to_string().c_str()); + + if (reduction_mode_ == ReductionMode::sdpor) { + if (stack_.empty()) { + execution_seq_ = sdpor::Execution(); + } else { + execution_seq_ = execution_seq_.get_prefix_up_to(stack_.size() - 1); + } + XBT_DEBUG("Additionally replaced corresponding SDPOR execution stack"); + } } void DFSExplorer::log_state() // override @@ -151,7 +155,7 @@ void DFSExplorer::run() #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. @@ -175,13 +179,13 @@ void DFSExplorer::run() } /* Actually answer the request: let's execute the selected request (MCed does one step) */ - state->execute_next(next, get_remote_app()); - on_transition_execute_signal(state->get_transition(), get_remote_app()); + const auto executed_transition = state->execute_next(next, get_remote_app()); + on_transition_execute_signal(state->get_transition_out().get(), get_remote_app()); // If there are processes to interleave and the maximum depth has not been // reached then perform one step of the exploration algorithm. - XBT_VERB("Execute %ld: %.60s (stack depth: %zu, state: %ld, %zu interleaves)", state->get_transition()->aid_, - state->get_transition()->to_string().c_str(), stack_.size(), state->get_num(), state->count_todo()); + XBT_VERB("Execute %ld: %.60s (stack depth: %zu, state: %ld, %zu interleaves)", state->get_transition_out()->aid_, + state->get_transition_out()->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) */ auto next_state = std::make_shared(get_remote_app(), state); @@ -192,27 +196,27 @@ void DFSExplorer::run() * Since the parent sleep set is used to compute the child sleep set, this need to be * done after next_state creation */ XBT_DEBUG("Marking Transition >>%s<< of process %ld done and adding it to the sleep set", - state->get_transition()->to_string().c_str(), state->get_transition()->aid_); - state->add_sleep_set(state->get_transition()); // Actors are marked done when they are considerd in ActorState + state->get_transition_out()->to_string().c_str(), state->get_transition_out()->aid_); + state->add_sleep_set(state->get_transition_out()); // Actors are marked done when they are considerd in ActorState /* DPOR persistent set procedure: * for each new transition considered, check if it depends on any other previous transition executed before it * on another process. If there exists one, find the more recent, and add its process to the interleave set. * 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_; + aid_t issuer_id = state->get_transition_out()->aid_; stack_t tmp_stack = stack_; while (not tmp_stack.empty()) { 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); + state->get_transition_out()->aid_ == prev_state->get_transition_out()->aid_) { + XBT_DEBUG("Simcall >>%s<< and >>%s<< with same issuer %ld", state->get_transition_out()->to_string().c_str(), + prev_state->get_transition_out()->to_string().c_str(), issuer_id); tmp_stack.pop_back(); continue; - } else if (prev_state->get_transition()->depends(state->get_transition())) { + } else if (prev_state->get_transition_out()->depends(state->get_transition_out().get())) { XBT_VERB("Dependent Transitions:"); - XBT_VERB(" %s (state=%ld)", prev_state->get_transition()->to_string().c_str(), prev_state->get_num()); - XBT_VERB(" %s (state=%ld)", state->get_transition()->to_string().c_str(), state->get_num()); + XBT_VERB(" %s (state=%ld)", prev_state->get_transition_out()->to_string().c_str(), prev_state->get_num()); + XBT_VERB(" %s (state=%ld)", state->get_transition_out()->to_string().c_str(), state->get_num()); if (prev_state->is_actor_enabled(issuer_id)) { if (not prev_state->is_actor_done(issuer_id)) { @@ -231,11 +235,55 @@ void DFSExplorer::run() break; } else { XBT_VERB("INDEPENDENT Transitions:"); - XBT_VERB(" %s (state=%ld)", prev_state->get_transition()->to_string().c_str(), prev_state->get_num()); - XBT_VERB(" %s (state=%ld)", state->get_transition()->to_string().c_str(), state->get_num()); + XBT_VERB(" %s (state=%ld)", prev_state->get_transition_out()->to_string().c_str(), prev_state->get_num()); + XBT_VERB(" %s (state=%ld)", state->get_transition_out()->to_string().c_str(), state->get_num()); } tmp_stack.pop_back(); } + } else if (reduction_mode_ == ReductionMode::sdpor) { + /** + * SDPOR Source Set Procedure: + * + * Find "reversible races" in the current execution with respect + * to the latest action `p`. For each such race, determine one thread + * not contained in the backtrack set at the "race point" `r` which + * "represents" the trace formed by first executing everything after + * `r` and then `p` to flip the race + */ + execution_seq_.push_transition(executed_transition.get()); + + xbt_assert(execution_seq_.get_latest_event_handle().has_value(), + "No events are contained in the SDPOR/OPDPOR execution " + "even though one was just added"); + const aid_t p = executed_transition->aid_; + const auto next_E_p = execution_seq_.get_latest_event_handle().value(); + + for (const auto racing_event_handle : execution_seq_.get_racing_events_of(next_E_p)) { + // To determine if the race is reversible, we have to ensure + // that actor `p` running `next_E_p` (viz. the event such that + // `racing_event -> (E_p) next_E_p` and no other event + // "happens-between" the two) is enabled in any equivalent + // execution where `racing_event` happens before `next_E_p`. + // + // Importantly, it is equivalent to checking if in ANY + // such equivalent execution sequence where `racing_event` + // happens-before `next_E_p` that `p` is enabled in `pre(racing_event, E.p)`. + // Thus it suffices to check THIS execution + // + // If the actor `p` is not enabled at s_[E'], it is not a *reversible* race + const std::shared_ptr prev_state = stack_[racing_event_handle]; + if (prev_state->is_actor_enabled(p)) { + // NOTE: To incorporate the idea of attempting to select the "best" + // backtrack point into SDPOR, instead of selecting the `first` initial, + // we should instead compute all choices and decide which is bes + const std::optional q = + execution_seq_.get_first_ssdpor_initial_from(racing_event_handle, prev_state->get_backtrack_set()); + if (q.has_value()) { + prev_state->consider_one(q.value()); + opened_states_.emplace_back(std::move(prev_state)); + } + } + } } // Before leaving that state, if the transition we just took can be taken multiple times, we @@ -247,7 +295,8 @@ void DFSExplorer::run() 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) */ + /* 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 @@ -264,12 +313,12 @@ void DFSExplorer::run() } dot_output("\"%ld\" -> \"%ld\" [%s];\n", state->get_num(), stack_.back()->get_num(), - state->get_transition()->dot_string().c_str()); + state->get_transition_out()->dot_string().c_str()); #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()); + state->get_transition_out()->dot_string().c_str()); #endif } } @@ -343,20 +392,48 @@ void DFSExplorer::backtrack() } #endif + // Search how to restore the backtracking point + State* init_state = nullptr; + std::deque replay_recipe; + for (auto* s = backtracking_point.get(); s != nullptr; s = s->get_parent_state().get()) { +#if SIMGRID_HAVE_STATEFUL_MC + if (s->get_system_state() != nullptr) { // Found a state that I can restore + init_state = s; + break; + } +#endif + if (s->get_transition_in() != nullptr) // The root has no transition_in + replay_recipe.push_front(s->get_transition_in().get()); + } + + // Restore the init_state, if any + if (init_state != nullptr) { +#if SIMGRID_HAVE_STATEFUL_MC + const auto* system_state = init_state->get_system_state(); + system_state->restore(*get_remote_app().get_remote_process_memory()); + on_restore_system_state_signal(init_state, get_remote_app()); +#endif + } else { // Restore the initial state if no intermediate state was found + get_remote_app().restore_initial_state(); + on_restore_initial_state_signal(get_remote_app()); + } + /* if no snapshot, we need to restore the initial state and replay the transitions */ - get_remote_app().restore_initial_state(); - on_restore_initial_state_signal(get_remote_app()); /* Traverse the stack from the state at position start and re-execute the transitions */ - for (auto& state : backtracking_point->get_recipe()) { - state->replay(get_remote_app()); - on_transition_replay_signal(state, get_remote_app()); + for (auto& transition : replay_recipe) { + transition->replay(get_remote_app()); + on_transition_replay_signal(transition, get_remote_app()); visited_states_count_++; } this->restore_stack(backtracking_point); } DFSExplorer::DFSExplorer(const std::vector& args, bool with_dpor, bool need_memory_info) - : Exploration(args, need_memory_info || _sg_mc_termination) + : Exploration(args, need_memory_info || _sg_mc_termination +#if SIMGRID_HAVE_STATEFUL_MC + || _sg_mc_checkpoint > 0 +#endif + ) { if (with_dpor) reduction_mode_ = ReductionMode::dpor;