X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/96d605fde63f72480bf570f7bc7609e2954cb2d7..a78e55a602586cf557968132c2d8c30af758af25:/src/mc/api/RemoteApp.cpp diff --git a/src/mc/api/RemoteApp.cpp b/src/mc/api/RemoteApp.cpp index 6037b6a1ec..df0c81fb58 100644 --- a/src/mc/api/RemoteApp.cpp +++ b/src/mc/api/RemoteApp.cpp @@ -1,38 +1,53 @@ -/* Copyright (c) 2015-2022. The SimGrid Team. All rights reserved. */ +/* Copyright (c) 2015-2023. 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 "src/mc/api/RemoteApp.hpp" -#include "src/internal_config.h" // HAVE_SMPI #include "src/mc/explo/Exploration.hpp" #include "src/mc/mc_config.hpp" -#if HAVE_SMPI -#include "smpi/smpi.h" -#include "src/smpi/include/private.hpp" -#endif +#include "xbt/asserts.h" #include "src/mc/api/State.hpp" +#include "src/mc/mc_config.hpp" #include "src/mc/mc_exit.hpp" #include "src/mc/mc_private.hpp" #include "xbt/log.h" #include "xbt/system_error.hpp" +#include -#include "signal.h" +#include #include +#include #include +#include #include #include #ifdef __linux__ #include #endif +#include +#include + +#ifdef __linux__ +#define WAITPID_CHECKED_FLAGS __WALL +#else +#define WAITPID_CHECKED_FLAGS 0 +#endif XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_Session, mc, "Model-checker session"); XBT_LOG_EXTERNAL_CATEGORY(mc_global); +static simgrid::config::Flag _sg_mc_setenv{ + "model-check/setenv", "Extra environment variables to pass to the child process (ex: 'AZE=aze;QWE=qwe').", "", + [](std::string_view value) { + xbt_assert(value.empty() || value.find('=', 0) != std::string_view::npos, + "The 'model-check/setenv' parameter must be like 'AZE=aze', but it does not contain an equal sign."); + }}; + namespace simgrid::mc { -template void run_child_process(int socket, Code code) +XBT_ATTRIB_NORETURN static void run_child_process(int socket, const std::vector& args) { /* On startup, simix_global_init() calls simgrid::mc::Client::initialize(), which checks whether the MC_ENV_SOCKET_FD * env variable is set. If so, MC mode is assumed, and the client is setup from its side @@ -53,17 +68,43 @@ template void run_child_process(int socket, Code code) setenv(MC_ENV_SOCKET_FD, std::to_string(socket).c_str(), 1); - code(); + /* Setup the tokenizer that parses the cfg:model-check/setenv parameter */ + using Tokenizer = boost::tokenizer>; + boost::char_separator semicol_sep(";"); + boost::char_separator equal_sep("="); + Tokenizer token_vars(_sg_mc_setenv.get(), semicol_sep); /* Iterate over all FOO=foo parts */ + for (const auto& token : token_vars) { + std::vector kv; + Tokenizer token_kv(token, equal_sep); + for (const auto& t : token_kv) /* Iterate over 'FOO' and then 'foo' in that 'FOO=foo' */ + kv.push_back(t); + xbt_assert(kv.size() == 2, "Parse error on 'model-check/setenv' value %s. Does it contain an equal sign?", + token.c_str()); + XBT_INFO("setenv '%s'='%s'", kv[0].c_str(), kv[1].c_str()); + setenv(kv[0].c_str(), kv[1].c_str(), 1); + } + + /* And now, exec the child process */ + int i = 1; + while (args[i] != nullptr && args[i][0] == '-') + i++; + + xbt_assert(args[i] != nullptr, + "Unable to find a binary to exec on the command line. Did you only pass config flags?"); + + execvp(args[i], args.data() + i); + XBT_CRITICAL("The model-checked process failed to exec(%s): %s.\n" + " Make sure that your binary exists on disk and is executable.", + args[i], strerror(errno)); + if (strchr(args[i], '=') != nullptr) + XBT_CRITICAL("If you want to pass environment variables to the application, please use --cfg=model-check/setenv:%s", + args[i]); + + xbt_die("Aborting now."); } -RemoteApp::RemoteApp(const std::function& code) +RemoteApp::RemoteApp(const std::vector& args) { -#if HAVE_SMPI - smpi_init_options(); // only performed once - xbt_assert(smpi_cfg_privatization() != SmpiPrivStrategies::MMAP, - "Please use the dlopen privatization schema when model-checking SMPI code"); -#endif - // Create an AF_LOCAL socketpair used for exchanging messages // between the model-checker process (ourselves) and the model-checked // process: @@ -75,112 +116,238 @@ RemoteApp::RemoteApp(const std::function& code) if (pid == 0) { // Child ::close(sockets[1]); - run_child_process(sockets[0], code); + run_child_process(sockets[0], args); DIE_IMPOSSIBLE; } // Parent (model-checker): ::close(sockets[0]); - xbt_assert(mc_model_checker == nullptr, "Did you manage to start the MC twice in this process?"); + checker_side_ = std::make_unique(sockets[1], pid); - auto process = std::make_unique(pid); - model_checker_ = std::make_unique(std::move(process), sockets[1]); + start(); - mc_model_checker = model_checker_.get(); - model_checker_->start(); + /* Take the initial snapshot */ + wait_for_requests(); + initial_snapshot_ = std::make_shared(0, page_store_, checker_side_->get_remote_memory()); } RemoteApp::~RemoteApp() { - this->close(); + initial_snapshot_ = nullptr; + shutdown(); } - -/** The application must be stopped. */ -void RemoteApp::take_initial_snapshot() +void RemoteApp::start() { - xbt_assert(initial_snapshot_ == nullptr); - model_checker_->wait_for_requests(); - initial_snapshot_ = std::make_shared(0); -} + XBT_DEBUG("Waiting for the model-checked process"); + int status; + + // The model-checked process SIGSTOP itself to signal it's ready: + const pid_t pid = checker_side_->get_pid(); + xbt_assert(waitpid(pid, &status, WAITPID_CHECKED_FLAGS) == pid && WIFSTOPPED(status) && WSTOPSIG(status) == SIGSTOP, + "Could not wait model-checked process"); + + errno = 0; +#ifdef __linux__ + ptrace(PTRACE_SETOPTIONS, pid, nullptr, PTRACE_O_TRACEEXIT); + ptrace(PTRACE_CONT, pid, 0, 0); +#elif defined BSD + ptrace(PT_CONTINUE, pid, (caddr_t)1, 0); +#else +#error "no ptrace equivalent coded for this platform" +#endif + xbt_assert(errno == 0, + "Ptrace does not seem to be usable in your setup (errno: %d). " + "If you run from within a docker, adding `--cap-add SYS_PTRACE` to the docker line may help. " + "If it does not help, please report this bug.", + errno); +} void RemoteApp::restore_initial_state() const { - this->initial_snapshot_->restore(&model_checker_->get_remote_process()); + this->initial_snapshot_->restore(checker_side_->get_remote_memory()); } -void RemoteApp::log_state() const +unsigned long RemoteApp::get_maxpid() const { - model_checker_->get_exploration()->log_state(); + // note: we could maybe cache it and count the actor creation on checker side too. + // But counting correctly accross state checkpoint/restore would be annoying. - if (not _sg_mc_dot_output_file.get().empty()) { - fprintf(dot_output, "}\n"); - fclose(dot_output); - } - if (getenv("SIMGRID_MC_SYSTEM_STATISTICS")) { - int ret = system("free"); - if (ret != 0) - XBT_WARN("Call to system(free) did not return 0, but %d", ret); - } -} + checker_side_->get_channel().send(MessageType::ACTORS_MAXPID); + s_mc_message_int_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_MAXPID_REPLY, + "Received unexpected message %s (%i); expected MessageType::ACTORS_MAXPID_REPLY (%i)", + to_c_str(answer.type), (int)answer.type, (int)MessageType::ACTORS_MAXPID_REPLY); -void RemoteApp::close() -{ - initial_snapshot_ = nullptr; - if (model_checker_) { - model_checker_->shutdown(); - model_checker_ = nullptr; - mc_model_checker = nullptr; - } + return answer.value; } -void RemoteApp::get_actors_status(std::map& whereto) +void RemoteApp::get_actors_status(std::map& whereto) const { - s_mc_message_t msg; - memset(&msg, 0, sizeof msg); - msg.type = simgrid::mc::MessageType::ACTORS_STATUS; - model_checker_->channel().send(msg); + // The messaging happens as follows: + // + // 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 + checker_side_->get_channel().send(MessageType::ACTORS_STATUS); s_mc_message_actors_status_answer_t answer; - ssize_t received = model_checker_->channel().receive(answer); - xbt_assert(received != -1, "Could not receive message"); - xbt_assert(received == sizeof(answer) && answer.type == MessageType::ACTORS_STATUS_REPLY, - "Received unexpected message %s (%i, size=%i) " - "expected MessageType::ACTORS_STATUS_REPLY (%i, size=%i)", - to_c_str(answer.type), (int)answer.type, (int)received, (int)MessageType::ACTORS_STATUS_REPLY, - (int)sizeof(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); + + // 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"); + + std::vector status(answer.count); + if (answer.count > 0) { + size_t size = status.size() * sizeof(s_mc_message_actors_status_one_t); + ssize_t received = checker_side_->get_channel().receive(status.data(), size); + xbt_assert(static_cast(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); - s_mc_message_actors_status_one_t status[answer.count]; - received = model_checker_->channel().receive(&status, sizeof(status)); - xbt_assert(static_cast(received) == sizeof(status)); + std::vector probes(answer.transition_count); + if (answer.transition_count > 0) { + for (auto& probe : probes) { + 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(received) == sizeof probe, + "Could not receive response to ACTORS_PROBE message (%zd bytes received != %zu bytes expected", + received, sizeof probe); + } + } whereto.clear(); - for (auto const& actor : status) - whereto.insert(std::make_pair(actor.aid, ActorState(actor.aid, actor.enabled, actor.max_considered))); + 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> actor_transitions; + for (int times_considered = 0; times_considered < actor.n_transitions; times_considered++, probes_iter++) { + std::stringstream stream((*probes_iter).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); + whereto.try_emplace(actor.aid, actor.aid, actor.enabled, actor.max_considered, std::move(actor_transitions)); + } } void RemoteApp::check_deadlock() const { - xbt_assert(model_checker_->channel().send(MessageType::DEADLOCK_CHECK) == 0, "Could not check deadlock state"); + xbt_assert(checker_side_->get_channel().send(MessageType::DEADLOCK_CHECK) == 0, "Could not check deadlock state"); s_mc_message_int_t message; - ssize_t s = model_checker_->channel().receive(message); - xbt_assert(s != -1, "Could not receive message"); - xbt_assert(s == sizeof(message) && message.type == MessageType::DEADLOCK_CHECK_REPLY, - "Received unexpected message %s (%i, size=%i) " - "expected MessageType::DEADLOCK_CHECK_REPLY (%i, size=%i)", - to_c_str(message.type), (int)message.type, (int)s, (int)MessageType::DEADLOCK_CHECK_REPLY, - (int)sizeof(message)); + ssize_t received = checker_side_->get_channel().receive(message); + xbt_assert(received != -1, "Could not receive message"); + xbt_assert(received == sizeof message, "Broken message (size=%zd; expected %zu)", received, sizeof message); + xbt_assert(message.type == MessageType::DEADLOCK_CHECK_REPLY, + "Received unexpected message %s (%i); expected MessageType::DEADLOCK_CHECK_REPLY (%i)", + to_c_str(message.type), (int)message.type, (int)MessageType::DEADLOCK_CHECK_REPLY); if (message.value != 0) { - XBT_CINFO(mc_global, "**************************"); - XBT_CINFO(mc_global, "*** DEADLOCK DETECTED ***"); - XBT_CINFO(mc_global, "**************************"); + auto* explo = Exploration::get_instance(); XBT_CINFO(mc_global, "Counter-example execution trace:"); - for (auto const& frame : model_checker_->get_exploration()->get_textual_trace()) + for (auto const& frame : explo->get_textual_trace()) XBT_CINFO(mc_global, " %s", frame.c_str()); - XBT_CINFO(mc_global, "Path = %s", model_checker_->get_exploration()->get_record_trace().to_string().c_str()); - log_state(); + XBT_INFO("You can debug the problem (and see the whole details) by rerunning out of simgrid-mc with " + "--cfg=model-check/replay:'%s'", + explo->get_record_trace().to_string().c_str()); + explo->log_state(); throw DeadlockError(); } } + +void RemoteApp::wait_for_requests() +{ + /* Resume the application */ + if (checker_side_->get_channel().send(MessageType::CONTINUE) != 0) + throw xbt::errno_error(); + get_remote_process_memory().clear_cache(); + + if (checker_side_->running()) + checker_side_->dispatch_events(); +} + +void RemoteApp::shutdown() +{ + XBT_DEBUG("Shutting down model-checker"); + + if (checker_side_->running()) { + XBT_DEBUG("Killing process"); + finalize_app(true); + kill(checker_side_->get_pid(), SIGKILL); + checker_side_->terminate(); + } +} + +Transition* RemoteApp::handle_simcall(aid_t aid, int times_considered, bool new_transition) +{ + s_mc_message_simcall_execute_t m = {}; + m.type = MessageType::SIMCALL_EXECUTE; + m.aid_ = aid; + m.times_considered_ = times_considered; + checker_side_->get_channel().send(m); + + get_remote_process_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 == 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()); + return deserialize_transition(aid, times_considered, stream); + } else + return nullptr; +} + +void RemoteApp::finalize_app(bool terminate_asap) +{ + s_mc_message_int_t m = {}; + m.type = MessageType::FINALIZE; + m.value = terminate_asap; + xbt_assert(checker_side_->get_channel().send(m) == 0, "Could not ask the app to finalize on need"); + + s_mc_message_t answer; + ssize_t s = checker_side_->get_channel().receive(answer); + xbt_assert(s != -1, "Could not receive answer to FINALIZE"); + xbt_assert(s == sizeof answer, "Broken message (size=%zd; expected %zu)", s, sizeof answer); + xbt_assert(answer.type == MessageType::FINALIZE_REPLY, + "Received unexpected message %s (%i); expected MessageType::FINALIZE_REPLY (%i)", to_c_str(answer.type), + (int)answer.type, (int)MessageType::FINALIZE_REPLY); +} + } // namespace simgrid::mc