-/* Copyright (c) 2016-2019. The SimGrid Team. All rights reserved. */
+/* Copyright (c) 2016-2022. The SimGrid Team. All rights reserved. */
/* This program is free software; you can redistribute it and/or modify it
* under the terms of the license (GNU LGPL) which comes with this package. */
-#include <cassert>
-#include <cstdio>
-
-#include <memory>
-#include <string>
-#include <vector>
-
-#include <xbt/log.h>
-#include <xbt/sysdep.h>
-
+#include "src/mc/checker/SafetyChecker.hpp"
#include "src/mc/Session.hpp"
-#include "src/mc/Transition.hpp"
#include "src/mc/VisitedState.hpp"
-#include "src/mc/checker/SafetyChecker.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/mc_request.hpp"
-#include "src/mc/mc_smx.hpp"
+#include "src/mc/transition/Transition.hpp"
#include "src/xbt/mmalloc/mmprivate.h"
+#include "xbt/log.h"
+#include "xbt/sysdep.h"
+
+#include <cassert>
+#include <cstdio>
+
+#include <memory>
+#include <string>
+#include <vector>
+
+using api = simgrid::mc::Api;
XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_safety, mc, "Logging specific to MC safety verification ");
namespace simgrid {
namespace mc {
-void SafetyChecker::check_non_termination(State* current_state)
+xbt::signal<void()> SafetyChecker::on_exploration_start_signal;
+xbt::signal<void()> SafetyChecker::on_backtracking_signal;
+
+xbt::signal<void(State*)> SafetyChecker::on_state_creation_signal;
+
+xbt::signal<void(State*)> SafetyChecker::on_restore_system_state_signal;
+xbt::signal<void()> SafetyChecker::on_restore_initial_state_signal;
+xbt::signal<void(Transition*)> SafetyChecker::on_transition_replay_signal;
+xbt::signal<void(Transition*)> SafetyChecker::on_transition_execute_signal;
+
+xbt::signal<void()> SafetyChecker::on_log_state_signal;
+
+void SafetyChecker::check_non_termination(const State* current_state)
{
for (auto state = stack_.rbegin(); state != stack_.rend(); ++state)
- if (snapshot_equal((*state)->system_state_.get(), current_state->system_state_.get())) {
- XBT_INFO("Non-progressive cycle: state %d -> state %d", (*state)->num_, current_state->num_);
+ if (api::get().snapshot_equal((*state)->system_state_.get(), current_state->system_state_.get())) {
+ XBT_INFO("Non-progressive cycle: state %ld -> state %ld", (*state)->num_, current_state->num_);
XBT_INFO("******************************************");
XBT_INFO("*** NON-PROGRESSIVE CYCLE DETECTED ***");
XBT_INFO("******************************************");
XBT_INFO("Counter-example execution trace:");
- for (auto const& s : mc_model_checker->getChecker()->get_textual_trace())
+ for (auto const& s : get_textual_trace())
XBT_INFO(" %s", s.c_str());
- dumpRecordPath();
- session->log_state();
+ XBT_INFO("Path = %s", get_record_trace().to_string().c_str());
+ api::get().log_state();
throw TerminationError();
}
std::vector<std::string> SafetyChecker::get_textual_trace() // override
{
std::vector<std::string> trace;
- for (auto const& state : stack_) {
- int value = state->transition_.argument_;
- smx_simcall_t req = &state->executed_req_;
- if (req)
- trace.push_back(request_to_string(req, value, RequestType::executed));
- }
+ for (auto const& state : stack_)
+ trace.push_back(state->get_transition()->to_string());
return trace;
}
void SafetyChecker::log_state() // override
{
- XBT_INFO("Expanded states = %lu", expanded_states_count_);
- XBT_INFO("Visited states = %lu", mc_model_checker->visited_states);
- XBT_INFO("Executed transitions = %lu", mc_model_checker->executed_transitions);
+ on_log_state_signal();
+ XBT_INFO("DFS exploration ended. %ld unique states visited; %ld backtracks (%lu transition replays, %lu states "
+ "visited overall)",
+ State::get_expanded_states(), backtrack_count_, api::get().mc_get_visited_states(),
+ Transition::get_replayed_transitions());
}
void SafetyChecker::run()
{
+ on_exploration_start_signal();
/* This function runs the DFS algorithm the state space.
* We do so iteratively instead of recursively, dealing with the call stack manually.
* This allows one to explore the call stack at will. */
State* state = stack_.back().get();
XBT_DEBUG("**************************************************");
- XBT_VERB("Exploration depth=%zu (state=%p, num %d)(%zu interleave)", stack_.size(), state, state->num_,
- state->interleave_size());
+ XBT_VERB("Exploration depth=%zu (state=%p, num %ld)(%zu interleave)", stack_.size(), state, state->num_,
+ state->count_todo());
- mc_model_checker->visited_states++;
+ api::get().mc_inc_visited_states();
// Backtrack if we reached the maximum depth
if (stack_.size() > (std::size_t)_sg_mc_max_depth) {
- XBT_WARN("/!\\ Max depth reached ! /!\\ ");
+ if (reductionMode_ == ReductionMode::dpor) {
+ XBT_ERROR("/!\\ Max depth of %d reached! THIS WILL PROBABLY BREAK the dpor reduction /!\\",
+ _sg_mc_max_depth.get());
+ XBT_ERROR("/!\\ If bad things happen, disable dpor with --cfg=model-check/reduction:none /!\\");
+ } else
+ XBT_WARN("/!\\ Max depth reached ! /!\\ ");
this->backtrack();
continue;
}
// Backtrack if we are revisiting a state we saw previously
if (visited_state_ != nullptr) {
- XBT_DEBUG("State already visited (equal to state %d), exploration stopped on this path.",
+ XBT_DEBUG("State already visited (equal to state %ld), exploration stopped on this path.",
visited_state_->original_num == -1 ? visited_state_->num : visited_state_->original_num);
visited_state_ = nullptr;
continue;
}
- // Search an enabled transition in the current state; backtrack if the interleave set is empty
- // get_request also sets state.transition to be the one corresponding to the returned req
- smx_simcall_t req = MC_state_choose_request(state);
- // req is now the transition of the process that was selected to be executed
+ // Search for the next transition
+ int next = state->next_transition();
- if (req == nullptr) {
- XBT_DEBUG("There are no more processes to interleave. (depth %zu)", stack_.size() + 1);
+ if (next < 0) { // If there is no more transition in the current state, backtrack.
+ XBT_DEBUG("There remains %zu actors, but none to interleave (depth %zu).",
+ mc_model_checker->get_remote_process().actors().size(), stack_.size() + 1);
+ if (mc_model_checker->get_remote_process().actors().empty())
+ mc_model_checker->finalize_app();
this->backtrack();
continue;
}
+ /* Actually answer the request: let's execute the selected request (MCed does one step) */
+ state->execute_next(next);
+ on_transition_execute_signal(state->get_transition());
+
// If there are processes to interleave and the maximum depth has not been
// reached then perform one step of the exploration algorithm.
- XBT_DEBUG("Execute: %s", request_to_string(req, state->transition_.argument_, RequestType::simix).c_str());
+ XBT_DEBUG("Execute: %s", state->get_transition()->to_string().c_str());
std::string req_str;
if (dot_output != nullptr)
- req_str = request_get_dot_output(req, state->transition_.argument_);
-
- mc_model_checker->executed_transitions++;
-
- /* Actually answer the request: let execute the selected request (MCed does one step) */
- this->get_session().execute(state->transition_);
+ req_str = api::get().request_get_dot_output(state->get_transition());
/* Create the new expanded state (copy the state of MCed into our MCer data) */
- std::unique_ptr<State> next_state = std::unique_ptr<State>(new State(++expanded_states_count_));
+ auto next_state = std::make_unique<State>();
+ on_state_creation_signal(next_state.get());
if (_sg_mc_termination)
this->check_non_termination(next_state.get());
/* 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(expanded_states_count_, next_state.get(), true);
+ visited_state_ = visited_states_.addVisitedState(next_state->num_, next_state.get(), true);
/* If this is a new state (or if we don't care about state-equality reduction) */
if (visited_state_ == nullptr) {
/* Get an enabled process and insert it in the interleave set of the next state */
- for (auto& remoteActor : mc_model_checker->process().actors()) {
+ auto actors = api::get().get_actors();
+ for (auto& remoteActor : actors) {
auto actor = remoteActor.copy.get_buffer();
- if (actor_is_enabled(actor)) {
- next_state->add_interleaving_set(actor);
+ if (get_session().actor_is_enabled(actor->get_pid())) {
+ next_state->mark_todo(actor->get_pid());
if (reductionMode_ == ReductionMode::dpor)
break; // With DPOR, we take the first enabled transition
}
}
if (dot_output != nullptr)
- std::fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", state->num_, next_state->num_, req_str.c_str());
+ std::fprintf(dot_output, "\"%ld\" -> \"%ld\" [%s];\n", state->num_, next_state->num_, req_str.c_str());
} else if (dot_output != nullptr)
- std::fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", state->num_,
+ std::fprintf(dot_output, "\"%ld\" -> \"%ld\" [%s];\n", state->num_,
visited_state_->original_num == -1 ? visited_state_->num : visited_state_->original_num,
req_str.c_str());
stack_.push_back(std::move(next_state));
}
- XBT_INFO("No property violation found.");
- session->log_state();
+ api::get().log_state();
}
void SafetyChecker::backtrack()
{
+ backtrack_count_++;
+ XBT_VERB("Backtracking from %s", get_record_trace().to_string().c_str());
+ on_backtracking_signal();
stack_.pop_back();
- /* Check for deadlocks */
- if (mc_model_checker->checkDeadlock()) {
- MC_show_deadlock();
- throw DeadlockError();
- }
+ api::get().mc_check_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 its
std::unique_ptr<State> state = std::move(stack_.back());
stack_.pop_back();
if (reductionMode_ == ReductionMode::dpor) {
- smx_simcall_t req = &state->internal_req_;
- 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_actor_t issuer = MC_smx_simcall_get_issuer(req);
+ aid_t issuer_id = state->get_transition()->aid_;
for (auto i = stack_.rbegin(); i != stack_.rend(); ++i) {
State* prev_state = i->get();
- if (request_depend(req, &prev_state->internal_req_)) {
- if (XBT_LOG_ISENABLED(mc_safety, xbt_log_priority_debug)) {
- XBT_DEBUG("Dependent Transitions:");
- int value = prev_state->transition_.argument_;
- smx_simcall_t prev_req = &prev_state->executed_req_;
- XBT_DEBUG("%s (state=%d)", simgrid::mc::request_to_string(prev_req, value, RequestType::internal).c_str(),
- prev_state->num_);
- value = state->transition_.argument_;
- prev_req = &state->executed_req_;
- XBT_DEBUG("%s (state=%d)", simgrid::mc::request_to_string(prev_req, value, RequestType::executed).c_str(),
- state->num_);
- }
-
- if (not prev_state->actor_states_[issuer->get_pid()].is_done())
- prev_state->add_interleaving_set(issuer);
- else
- XBT_DEBUG("Process %p is in done set", req->issuer_);
+ if (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);
break;
- } else if (req->issuer_ == prev_state->internal_req_.issuer_) {
- XBT_DEBUG("Simcall %s and %s with same issuer", SIMIX_simcall_name(req->call_),
- SIMIX_simcall_name(prev_state->internal_req_.call_));
+ } else if (prev_state->get_transition()->depends(state->get_transition())) {
+ XBT_VERB("Dependent Transitions:");
+ XBT_VERB(" %s (state=%ld)", prev_state->get_transition()->to_string().c_str(), prev_state->num_);
+ XBT_VERB(" %s (state=%ld)", state->get_transition()->to_string().c_str(), state->num_);
+
+ if (not prev_state->actor_states_[issuer_id].is_done())
+ prev_state->mark_todo(issuer_id);
+ else
+ XBT_DEBUG("Actor %ld is in done set", issuer_id);
break;
} else {
- const smx_actor_t previous_issuer = MC_smx_simcall_get_issuer(&prev_state->internal_req_);
- XBT_DEBUG("Simcall %s, process %ld (state %d) and simcall %s, process %ld (state %d) are independent",
- SIMIX_simcall_name(req->call_), issuer->get_pid(), state->num_,
- SIMIX_simcall_name(prev_state->internal_req_.call_), previous_issuer->get_pid(), prev_state->num_);
+ XBT_VERB("INDEPENDENT Transitions:");
+ XBT_VERB(" %s (state=%ld)", prev_state->get_transition()->to_string().c_str(), prev_state->num_);
+ XBT_VERB(" %s (state=%ld)", state->get_transition()->to_string().c_str(), state->num_);
}
}
}
- if (state->interleave_size() && stack_.size() < (std::size_t)_sg_mc_max_depth) {
+ if (state->count_todo() && 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 %zu", state->num_, stack_.size() + 1);
+ XBT_DEBUG("Back-tracking to state %ld at depth %zu", state->num_, stack_.size() + 1);
stack_.push_back(std::move(state));
this->restore_state();
- XBT_DEBUG("Back-tracking to state %d at depth %zu done", stack_.back()->num_, stack_.size());
+ XBT_DEBUG("Back-tracking to state %ld at depth %zu done", stack_.back()->num_, stack_.size());
break;
} else {
- XBT_DEBUG("Delete state %d at depth %zu", state->num_, stack_.size() + 1);
+ XBT_DEBUG("Delete state %ld at depth %zu", state->num_, stack_.size() + 1);
}
}
}
void SafetyChecker::restore_state()
{
- /* Intermediate backtracking */
+ /* If asked to rollback on a state that has a snapshot, restore it */
State* last_state = stack_.back().get();
if (last_state->system_state_) {
- last_state->system_state_->restore(&mc_model_checker->process());
+ api::get().restore_state(last_state->system_state_);
+ on_restore_system_state_signal(last_state);
return;
}
- /* Restore the initial state */
- session->restore_initial_state();
+ /* if no snapshot, we need to restore the initial state and replay the transitions */
+ get_session().restore_initial_state();
+ on_restore_initial_state_signal();
/* Traverse the stack from the state at position start and re-execute the transitions */
for (std::unique_ptr<State> const& state : stack_) {
- if (state == stack_.back())
+ if (state == stack_.back()) // If we are arrived on the target state, don't replay the outgoing transition *.
break;
- session->execute(state->transition_);
+ state->get_transition()->replay();
+ on_transition_replay_signal(state->get_transition());
/* Update statistics */
- mc_model_checker->visited_states++;
- mc_model_checker->executed_transitions++;
+ api::get().mc_inc_visited_states();
}
}
-SafetyChecker::SafetyChecker(Session& s) : Checker(s)
+SafetyChecker::SafetyChecker(Session* session) : Checker(session)
{
reductionMode_ = reduction_mode;
if (_sg_mc_termination)
if (_sg_mc_termination)
XBT_INFO("Check non progressive cycles");
else
- XBT_INFO("Check a safety property. Reduction is: %s.",
+ XBT_INFO("Start a DFS exploration. Reduction is: %s.",
(reductionMode_ == ReductionMode::none ? "none"
: (reductionMode_ == ReductionMode::dpor ? "dpor" : "unknown")));
- session->initialize();
+
+ get_session().take_initial_snapshot();
XBT_DEBUG("Starting the safety algorithm");
- std::unique_ptr<State> initial_state = std::unique_ptr<State>(new State(++expanded_states_count_));
+ auto initial_state = std::make_unique<State>();
XBT_DEBUG("**************************************************");
- XBT_DEBUG("Initial state");
/* Get an enabled actor and insert it in the interleave set of the initial state */
- for (auto& actor : mc_model_checker->process().actors())
- if (actor_is_enabled(actor.copy.get_buffer())) {
- initial_state->add_interleaving_set(actor.copy.get_buffer());
- if (reductionMode_ != ReductionMode::none)
+ auto actors = api::get().get_actors();
+ XBT_DEBUG("Initial state. %zu actors to consider", actors.size());
+ for (auto& actor : actors) {
+ aid_t aid = actor.copy.get_buffer()->get_pid();
+ if (get_session().actor_is_enabled(aid)) {
+ initial_state->mark_todo(aid);
+ if (reductionMode_ == ReductionMode::dpor) {
+ XBT_DEBUG("Actor %ld is TODO, DPOR is ON so let's go for this one.", aid);
break;
+ }
+ XBT_DEBUG("Actor %ld is TODO", aid);
}
+ }
stack_.push_back(std::move(initial_state));
}
-Checker* createSafetyChecker(Session& s)
+Checker* create_safety_checker(Session* session)
{
- return new SafetyChecker(s);
+ return new SafetyChecker(session);
}
} // namespace mc