From 8cbabb7df8c91256606fcbfdc31419e54a0bd857 Mon Sep 17 00:00:00 2001 From: Gabriel Corona Date: Tue, 5 Apr 2016 11:03:50 +0200 Subject: [PATCH] [mc] Create SafetyChecker::backtrack() method --- src/mc/SafetyChecker.cpp | 280 ++++++++++++++++++++------------------- src/mc/SafetyChecker.hpp | 1 + 2 files changed, 143 insertions(+), 138 deletions(-) diff --git a/src/mc/SafetyChecker.cpp b/src/mc/SafetyChecker.cpp index 68d89d75f3..567c82da36 100644 --- a/src/mc/SafetyChecker.cpp +++ b/src/mc/SafetyChecker.cpp @@ -96,7 +96,6 @@ int SafetyChecker::run() this->init(); int value; - smx_simcall_t req = nullptr; while (!stack_.empty()) { @@ -109,170 +108,175 @@ int SafetyChecker::run() stack_.size(), state, state->num, MC_state_interleave_size(state)); - /* Update statistics */ mc_stats->visited_states++; - /* If there are processes to interleave and the maximum depth has not been reached - then perform one step of the exploration algorithm */ - if (stack_.size() <= (std::size_t) _sg_mc_max_depth - && (req = MC_state_get_request(state, &value)) != nullptr - && visitedState_ == nullptr) { + // The interleave set is empty or the maximum depth is reached, + // let's back-track. + smx_simcall_t req = nullptr; + if (stack_.size() > (std::size_t) _sg_mc_max_depth + || (req = MC_state_get_request(state, &value)) == nullptr + || visitedState_ != nullptr) { + int res = this->backtrack(); + if (res) + return res; + else + continue; + } - char* req_str = simgrid::mc::request_to_string(req, value, simgrid::mc::RequestType::simix); - XBT_DEBUG("Execute: %s", req_str); - xbt_free(req_str); + // If there are processes to interleave and the maximum depth has not been + // reached then perform one step of the exploration algorithm. + char* req_str = simgrid::mc::request_to_string(req, value, simgrid::mc::RequestType::simix); + XBT_DEBUG("Execute: %s", req_str); + xbt_free(req_str); - if (dot_output != nullptr) - req_str = simgrid::mc::request_get_dot_output(req, value); + if (dot_output != nullptr) + req_str = simgrid::mc::request_get_dot_output(req, value); - MC_state_set_executed_request(state, req, value); - mc_stats->executed_transitions++; + MC_state_set_executed_request(state, req, value); + mc_stats->executed_transitions++; - // TODO, bundle both operations in a single message - // MC_execute_transition(req, value) + // TODO, bundle both operations in a single message + // MC_execute_transition(req, value) - /* Answer the request */ - simgrid::mc::handle_simcall(req, value); - mc_model_checker->wait_for_requests(); + /* Answer the request */ + simgrid::mc::handle_simcall(req, value); + mc_model_checker->wait_for_requests(); - /* Create the new expanded state */ - std::unique_ptr next_state = - std::unique_ptr(MC_state_new()); + /* Create the new expanded state */ + std::unique_ptr next_state = + std::unique_ptr(MC_state_new()); - if (_sg_mc_termination && this->checkNonTermination(next_state.get())) { - MC_show_non_termination(); - return SIMGRID_MC_EXIT_NON_TERMINATION; - } + if (_sg_mc_termination && this->checkNonTermination(next_state.get())) { + MC_show_non_termination(); + return SIMGRID_MC_EXIT_NON_TERMINATION; + } - if (_sg_mc_visited == 0 - || (visitedState_ = visitedStates_.addVisitedState(next_state.get(), true)) == nullptr) { + if (_sg_mc_visited == 0 + || (visitedState_ = visitedStates_.addVisitedState(next_state.get(), true)) == nullptr) { - /* Get an enabled process and insert it in the interleave set of the next state */ - for (auto& p : mc_model_checker->process().simix_processes()) - if (simgrid::mc::process_is_enabled(&p.copy)) { - MC_state_interleave_process(next_state.get(), &p.copy); - if (reductionMode_ != simgrid::mc::ReductionMode::none) - break; - } + /* Get an enabled process and insert it in the interleave set of the next state */ + for (auto& p : mc_model_checker->process().simix_processes()) + if (simgrid::mc::process_is_enabled(&p.copy)) { + MC_state_interleave_process(next_state.get(), &p.copy); + if (reductionMode_ != simgrid::mc::ReductionMode::none) + break; + } - if (dot_output != nullptr) - std::fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", state->num, next_state->num, req_str); + if (dot_output != nullptr) + std::fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", state->num, next_state->num, req_str); - } else if (dot_output != nullptr) - std::fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", state->num, visitedState_->other_num == -1 ? visitedState_->num : visitedState_->other_num, req_str); + } else if (dot_output != nullptr) + std::fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", state->num, visitedState_->other_num == -1 ? visitedState_->num : visitedState_->other_num, req_str); - stack_.push_back(std::move(next_state)); + stack_.push_back(std::move(next_state)); - if (dot_output != nullptr) - xbt_free(req_str); + if (dot_output != nullptr) + xbt_free(req_str); + } - /* Let's loop again */ + XBT_INFO("No property violation found."); + MC_print_statistics(mc_stats); + initial_global_state = nullptr; + return SIMGRID_MC_EXIT_SUCCESS; +} - /* The interleave set is empty or the maximum depth is reached, let's back-track */ - } else { +int SafetyChecker::backtrack() +{ + if (stack_.size() > (std::size_t) _sg_mc_max_depth + || visitedState_ != nullptr) { + if (visitedState_ == nullptr) + XBT_WARN("/!\\ Max depth reached ! /!\\ "); + else + XBT_DEBUG("State already visited (equal to state %d)," + " exploration stopped on this path.", + visitedState_->other_num == -1 ? visitedState_->num : visitedState_->other_num); + } else + XBT_DEBUG("There are no more processes to interleave. (depth %zi)", + stack_.size() + 1); + + stack_.pop_back(); + + visitedState_ = nullptr; + + /* Check for deadlocks */ + if (mc_model_checker->checkDeadlock()) { + MC_show_deadlock(); + return SIMGRID_MC_EXIT_DEADLOCK; + } - if (stack_.size() > (std::size_t) _sg_mc_max_depth - || visitedState_ != nullptr) { - if (visitedState_ == nullptr) - XBT_WARN("/!\\ Max depth reached ! /!\\ "); - else - XBT_DEBUG("State already visited (equal to state %d)," - " exploration stopped on this path.", - visitedState_->other_num == -1 ? visitedState_->num : visitedState_->other_num); - } else - XBT_DEBUG("There are no more processes to interleave. (depth %zi)", - stack_.size() + 1); - - /* Trash the current state, no longer needed */ - XBT_DEBUG("Delete state %d at depth %zi", state->num, stack_.size()); - stack_.pop_back(); - - visitedState_ = nullptr; - - /* Check for deadlocks */ - if (mc_model_checker->checkDeadlock()) { - MC_show_deadlock(); - return SIMGRID_MC_EXIT_DEADLOCK; - } + /* Traverse the stack backwards until a state with a non empty interleave + set is found, deleting all the states that have it empty in the way. + For each deleted state, check if the request that has generated it + (from it's predecesor state), depends on any other previous request + executed before it. If it does then add it to the interleave set of the + state that executed that previous request. */ - /* Traverse the stack backwards until a state with a non empty interleave - set is found, deleting all the states that have it empty in the way. - For each deleted state, check if the request that has generated it - (from it's predecesor state), depends on any other previous request - executed before it. If it does then add it to the interleave set of the - state that executed that previous request. */ - - while (!stack_.empty()) { - std::unique_ptr state = std::move(stack_.back()); - stack_.pop_back(); - if (reductionMode_ == simgrid::mc::ReductionMode::dpor) { - req = MC_state_get_internal_request(state.get()); - if (req->call == SIMCALL_MUTEX_LOCK || req->call == SIMCALL_MUTEX_TRYLOCK) - xbt_die("Mutex is currently not supported with DPOR, " - "use --cfg=model-check/reduction:none"); - const smx_process_t issuer = MC_smx_simcall_get_issuer(req); - for (auto i = stack_.rbegin(); i != stack_.rend(); ++i) { - simgrid::mc::State* prev_state = i->get(); - if (reductionMode_ != simgrid::mc::ReductionMode::none - && simgrid::mc::request_depend(req, MC_state_get_internal_request(prev_state))) { - if (XBT_LOG_ISENABLED(mc_safety, xbt_log_priority_debug)) { - XBT_DEBUG("Dependent Transitions:"); - smx_simcall_t prev_req = MC_state_get_executed_request(prev_state, &value); - char* req_str = simgrid::mc::request_to_string(prev_req, value, simgrid::mc::RequestType::internal); - XBT_DEBUG("%s (state=%d)", req_str, prev_state->num); - xbt_free(req_str); - prev_req = MC_state_get_executed_request(state.get(), &value); - req_str = simgrid::mc::request_to_string(prev_req, value, simgrid::mc::RequestType::executed); - XBT_DEBUG("%s (state=%d)", req_str, state->num); - xbt_free(req_str); - } - - if (!MC_state_process_is_done(prev_state, issuer)) - MC_state_interleave_process(prev_state, issuer); - else - XBT_DEBUG("Process %p is in done set", req->issuer); - - break; - - } else if (req->issuer == MC_state_get_internal_request(prev_state)->issuer) { - - XBT_DEBUG("Simcall %d and %d with same issuer", req->call, MC_state_get_internal_request(prev_state)->call); - break; - - } else { - - const smx_process_t previous_issuer = MC_smx_simcall_get_issuer(MC_state_get_internal_request(prev_state)); - XBT_DEBUG("Simcall %d, process %lu (state %d) and simcall %d, process %lu (state %d) are independant", - req->call, issuer->pid, state->num, - MC_state_get_internal_request(prev_state)->call, - previous_issuer->pid, - prev_state->num); - - } + while (!stack_.empty()) { + std::unique_ptr state = std::move(stack_.back()); + stack_.pop_back(); + if (reductionMode_ == simgrid::mc::ReductionMode::dpor) { + smx_simcall_t req = MC_state_get_internal_request(state.get()); + if (req->call == SIMCALL_MUTEX_LOCK || req->call == SIMCALL_MUTEX_TRYLOCK) + xbt_die("Mutex is currently not supported with DPOR, " + "use --cfg=model-check/reduction:none"); + const smx_process_t issuer = MC_smx_simcall_get_issuer(req); + for (auto i = stack_.rbegin(); i != stack_.rend(); ++i) { + simgrid::mc::State* prev_state = i->get(); + if (reductionMode_ != simgrid::mc::ReductionMode::none + && simgrid::mc::request_depend(req, MC_state_get_internal_request(prev_state))) { + if (XBT_LOG_ISENABLED(mc_safety, xbt_log_priority_debug)) { + XBT_DEBUG("Dependent Transitions:"); + int value; + smx_simcall_t prev_req = MC_state_get_executed_request(prev_state, &value); + char* req_str = simgrid::mc::request_to_string(prev_req, value, simgrid::mc::RequestType::internal); + XBT_DEBUG("%s (state=%d)", req_str, prev_state->num); + xbt_free(req_str); + prev_req = MC_state_get_executed_request(state.get(), &value); + req_str = simgrid::mc::request_to_string(prev_req, value, simgrid::mc::RequestType::executed); + XBT_DEBUG("%s (state=%d)", req_str, state->num); + xbt_free(req_str); } - } - if (MC_state_interleave_size(state.get()) - && stack_.size() < (std::size_t) _sg_mc_max_depth) { - /* We found a back-tracking point, let's loop */ - XBT_DEBUG("Back-tracking to state %d at depth %zi", - state->num, stack_.size() + 1); - stack_.push_back(std::move(state)); - simgrid::mc::replay(stack_); - XBT_DEBUG("Back-tracking to state %d at depth %zi done", - stack_.back()->num, stack_.size()); + if (!MC_state_process_is_done(prev_state, issuer)) + MC_state_interleave_process(prev_state, issuer); + else + XBT_DEBUG("Process %p is in done set", req->issuer); + break; + + } else if (req->issuer == MC_state_get_internal_request(prev_state)->issuer) { + + XBT_DEBUG("Simcall %d and %d with same issuer", req->call, MC_state_get_internal_request(prev_state)->call); + break; + } else { - XBT_DEBUG("Delete state %d at depth %zi", - state->num, stack_.size() + 1); + + const smx_process_t previous_issuer = MC_smx_simcall_get_issuer(MC_state_get_internal_request(prev_state)); + XBT_DEBUG("Simcall %d, process %lu (state %d) and simcall %d, process %lu (state %d) are independant", + req->call, issuer->pid, state->num, + MC_state_get_internal_request(prev_state)->call, + previous_issuer->pid, + prev_state->num); + } } } - } - XBT_INFO("No property violation found."); - MC_print_statistics(mc_stats); - initial_global_state = nullptr; + if (MC_state_interleave_size(state.get()) + && stack_.size() < (std::size_t) _sg_mc_max_depth) { + /* We found a back-tracking point, let's loop */ + XBT_DEBUG("Back-tracking to state %d at depth %zi", + state->num, stack_.size() + 1); + stack_.push_back(std::move(state)); + simgrid::mc::replay(stack_); + XBT_DEBUG("Back-tracking to state %d at depth %zi done", + stack_.back()->num, stack_.size()); + break; + } else { + XBT_DEBUG("Delete state %d at depth %zi", + state->num, stack_.size() + 1); + } + } return SIMGRID_MC_EXIT_SUCCESS; } diff --git a/src/mc/SafetyChecker.hpp b/src/mc/SafetyChecker.hpp index 39b083454a..8d237cea3e 100644 --- a/src/mc/SafetyChecker.hpp +++ b/src/mc/SafetyChecker.hpp @@ -31,6 +31,7 @@ private: // Temp void init(); bool checkNonTermination(simgrid::mc::State* current_state); + int backtrack(); private: /** Stack representing the position in the exploration graph */ std::list> stack_; -- 2.20.1