#include <algorithm>
#include <array>
+#include <limits.h>
#include <memory>
#include <numeric>
#include <string>
-
#include <sys/ptrace.h>
+#include <sys/un.h>
#include <sys/wait.h>
XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_Session, mc, "Model-checker session");
namespace simgrid::mc {
-RemoteApp::RemoteApp(const std::vector<char*>& args, bool need_memory_introspection)
-{
- for (auto* arg : args)
- app_args_.push_back(arg);
-
- checker_side_ = std::make_unique<simgrid::mc::CheckerSide>(app_args_, need_memory_introspection);
-
- if (need_memory_introspection)
- initial_snapshot_ = std::make_shared<simgrid::mc::Snapshot>(0, page_store_, *checker_side_->get_remote_memory());
-}
+static std::string master_socket_name;
-RemoteApp::~RemoteApp()
+RemoteApp::RemoteApp(const std::vector<char*>& args) : app_args_(args)
{
- initial_snapshot_ = nullptr;
- checker_side_ = nullptr;
+ master_socket_ = socket(AF_UNIX,
+#ifdef __APPLE__
+ SOCK_STREAM, /* Mac OSX does not have AF_UNIX + SOCK_SEQPACKET, even if that's faster */
+#else
+ SOCK_SEQPACKET,
+#endif
+ 0);
+ xbt_assert(master_socket_ != -1, "Cannot create the master socket: %s", strerror(errno));
+
+ master_socket_name = "/tmp/simgrid-mc-" + std::to_string(getpid());
+ master_socket_name.resize(MC_SOCKET_NAME_LEN); // truncate socket name if it's too long
+ master_socket_name.back() = '\0'; // ensure the data are null-terminated
+#ifdef __linux__
+ master_socket_name[0] = '\0'; // abstract socket, automatically removed after close
+#else
+ unlink(master_socket_name.c_str()); // remove possible stale socket before bind
+ atexit([]() {
+ if (not master_socket_name.empty())
+ unlink(master_socket_name.c_str());
+ master_socket_name.clear();
+ });
+#endif
+
+ struct sockaddr_un serv_addr = {};
+ serv_addr.sun_family = AF_UNIX;
+ master_socket_name.copy(serv_addr.sun_path, MC_SOCKET_NAME_LEN);
+
+ xbt_assert(bind(master_socket_, (struct sockaddr*)&serv_addr, sizeof serv_addr) >= 0,
+ "Cannot bind the master socket to %c%s: %s.", (serv_addr.sun_path[0] ? serv_addr.sun_path[0] : '@'),
+ serv_addr.sun_path + 1, strerror(errno));
+
+ xbt_assert(listen(master_socket_, SOMAXCONN) >= 0, "Cannot listen to the master socket: %s.", strerror(errno));
+
+ application_factory_ = std::make_unique<simgrid::mc::CheckerSide>(app_args_);
+ checker_side_ = application_factory_->clone(master_socket_, master_socket_name);
}
void RemoteApp::restore_initial_state()
{
- if (initial_snapshot_ == nullptr) { // No memory introspection
- // We need to destroy the existing CheckerSide before creating the new one, or libevent gets crazy
- checker_side_.reset(nullptr);
- checker_side_.reset(new simgrid::mc::CheckerSide(app_args_, true));
- } else
- initial_snapshot_->restore(*checker_side_->get_remote_memory());
+ checker_side_ = application_factory_->clone(master_socket_, master_socket_name);
}
unsigned long RemoteApp::get_maxpid() const
//
// CheckerSide AppSide
// send ACTORS_STATUS ---->
- // <----- send ACTORS_STATUS_REPLY
- // <----- send `N` `s_mc_message_actors_status_one_t` structs
- // <----- send `M` `s_mc_message_simcall_probe_one_t` structs
+ // <----- send ACTORS_STATUS_REPLY_COUNT
+ // <----- send `N` ACTORS_STATUS_REPLY_TRANSITION (s_mc_message_actors_status_one_t)
+ // <----- send `M` ACTORS_STATUS_REPLY_SIMCALL (s_mc_message_simcall_probe_one_t)
+ //
+ // Note that we also receive disabled transitions, because the guiding strategies need them to decide what could
+ // unlock actors.
+
checker_side_->get_channel().send(MessageType::ACTORS_STATUS);
s_mc_message_actors_status_answer_t answer;
ssize_t answer_size = checker_side_->get_channel().receive(answer);
xbt_assert(answer_size != -1, "Could not receive message");
xbt_assert(answer_size == sizeof answer, "Broken message (size=%zd; expected %zu)", answer_size, sizeof answer);
- xbt_assert(answer.type == MessageType::ACTORS_STATUS_REPLY,
- "Received unexpected message %s (%i); expected MessageType::ACTORS_STATUS_REPLY (%i)",
- to_c_str(answer.type), (int)answer.type, (int)MessageType::ACTORS_STATUS_REPLY);
+ xbt_assert(answer.type == MessageType::ACTORS_STATUS_REPLY_COUNT,
+ "%d Received unexpected message %s (%i); expected MessageType::ACTORS_STATUS_REPLY_COUNT (%i)", getpid(),
+ to_c_str(answer.type), (int)answer.type, (int)MessageType::ACTORS_STATUS_REPLY_COUNT);
// Message sanity checks
- xbt_assert(answer.count >= 0, "Received an ACTOR_STATUS_REPLY message with an actor count of '%d' < 0", answer.count);
- xbt_assert(answer.transition_count >= 0, "Received an ACTOR_STATUS_REPLY message with transition_count '%d' < 0",
- answer.transition_count);
- xbt_assert(answer.transition_count == 0 || answer.count >= 0,
- "Received an ACTOR_STATUS_REPLY message with no actor data "
- "but with transition data nonetheless");
+ xbt_assert(answer.count >= 0, "Received an ACTORS_STATUS_REPLY_COUNT message with an actor count of '%d' < 0",
+ answer.count);
std::vector<s_mc_message_actors_status_one_t> status(answer.count);
if (answer.count > 0) {
xbt_assert(static_cast<size_t>(received) == size);
}
- // Ensures that each actor sends precisely `answer.transition_count` transitions. While technically
- // this doesn't catch the edge case where actor A sends 3 instead of 2 and actor B sends 2 instead
- // of 3 transitions, that is ignored here since that invariant needs to be enforced on the AppSide
- const auto expected_transitions = std::accumulate(
- status.begin(), status.end(), 0, [](int total, const auto& actor) { return total + actor.n_transitions; });
- xbt_assert(expected_transitions == answer.transition_count,
- "Expected to receive %d transition(s) but was only notified of %d by the app side", expected_transitions,
- answer.transition_count);
-
- std::vector<s_mc_message_simcall_probe_one_t> probes(answer.transition_count);
- if (answer.transition_count > 0) {
- for (auto& probe : probes) {
+ whereto.clear();
+
+ for (const auto& actor : status) {
+ std::vector<std::shared_ptr<Transition>> actor_transitions;
+ int n_transitions = actor.max_considered;
+ for (int times_considered = 0; times_considered < n_transitions; times_considered++) {
+ s_mc_message_simcall_probe_one_t probe;
ssize_t received = checker_side_->get_channel().receive(probe);
xbt_assert(received >= 0, "Could not receive response to ACTORS_PROBE message (%s)", strerror(errno));
xbt_assert(static_cast<size_t>(received) == sizeof probe,
"Could not receive response to ACTORS_PROBE message (%zd bytes received != %zu bytes expected",
received, sizeof probe);
- }
- }
- whereto.clear();
- std::move_iterator probes_iter(probes.begin());
-
- for (const auto& actor : status) {
- xbt_assert(actor.n_transitions == 0 || actor.n_transitions == actor.max_considered,
- "If any transitions are serialized for an actor, it must match the "
- "total number of transitions that can be considered for the actor "
- "(currently %d), but only %d transition(s) was/were said to be encoded",
- actor.max_considered, actor.n_transitions);
-
- std::vector<std::shared_ptr<Transition>> actor_transitions;
- for (int times_considered = 0; times_considered < actor.n_transitions; times_considered++, probes_iter++) {
- std::stringstream stream((*probes_iter).buffer.data());
+ std::stringstream stream(probe.buffer.data());
actor_transitions.emplace_back(deserialize_transition(actor.aid, times_considered, stream));
}
- XBT_DEBUG("Received %zu transitions for actor %ld", actor_transitions.size(), actor.aid);
+ XBT_DEBUG("Received %zu transitions for actor %ld. The first one is %s", actor_transitions.size(), actor.aid,
+ (actor_transitions.size() > 0 ? actor_transitions[0]->to_string().c_str() : "null"));
whereto.try_emplace(actor.aid, actor.aid, actor.enabled, actor.max_considered, std::move(actor_transitions));
}
}
"--cfg=model-check/replay:'%s'",
explo->get_record_trace().to_string().c_str());
explo->log_state();
- throw DeadlockError();
+ throw McError(ExitStatus::DEADLOCK);
}
}
m.times_considered_ = times_considered;
checker_side_->get_channel().send(m);
- auto* memory = get_remote_process_memory();
- if (memory != nullptr)
- memory->clear_cache();
if (checker_side_->running())
checker_side_->dispatch_events(); // The app may send messages while processing the transition
s_mc_message_simcall_execute_answer_t answer;
ssize_t s = checker_side_->get_channel().receive(answer);
xbt_assert(s != -1, "Could not receive message");
+ xbt_assert(s > 0 && answer.type == MessageType::SIMCALL_EXECUTE_REPLY,
+ "%d Received unexpected message %s (%i); expected MessageType::SIMCALL_EXECUTE_REPLY (%i)", getpid(),
+ to_c_str(answer.type), (int)answer.type, (int)MessageType::SIMCALL_EXECUTE_REPLY);
xbt_assert(s == sizeof answer, "Broken message (size=%zd; expected %zu)", s, sizeof answer);
- xbt_assert(answer.type == MessageType::SIMCALL_EXECUTE_ANSWER,
- "Received unexpected message %s (%i); expected MessageType::SIMCALL_EXECUTE_ANSWER (%i)",
- to_c_str(answer.type), (int)answer.type, (int)MessageType::SIMCALL_EXECUTE_ANSWER);
if (new_transition) {
std::stringstream stream(answer.buffer.data());
