#include "src/mc/remote/CheckerSide.hpp"
#include "src/mc/explo/Exploration.hpp"
+#include "src/mc/mc_environ.h"
#include "xbt/config.hpp"
#include "xbt/system_error.hpp"
-#if SIMGRID_HAVE_STATEFUL_MC
-#include "src/mc/explo/LivenessChecker.hpp"
-#include "src/mc/sosp/RemoteProcessMemory.hpp"
-#endif
-
#ifdef __linux__
#include <sys/prctl.h>
#endif
namespace simgrid::mc {
-XBT_ATTRIB_NORETURN static void run_child_process(int socket, const std::vector<char*>& args, bool need_ptrace)
+XBT_ATTRIB_NORETURN static void run_child_process(int socket, const std::vector<char*>& 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
xbt_assert(prctl(PR_SET_PDEATHSIG, SIGHUP) == 0, "Could not PR_SET_PDEATHSIG");
#endif
- // Remove CLOEXEC to pass the socket to the application
- int fdflags = fcntl(socket, F_GETFD, 0);
- xbt_assert(fdflags != -1 && fcntl(socket, F_SETFD, fdflags & ~FD_CLOEXEC) != -1,
- "Could not remove CLOEXEC for socket");
-
setenv(MC_ENV_SOCKET_FD, std::to_string(socket).c_str(), 1);
- if (need_ptrace)
- setenv("MC_NEED_PTRACE", "1", 1);
/* Setup the tokenizer that parses the cfg:model-check/setenv parameter */
using Tokenizer = boost::tokenizer<boost::char_separator<char>>;
#elif defined BSD
ptrace(PT_CONTINUE, pid, (caddr_t)1, 0);
#else
-#error "no ptrace equivalent coded for this platform"
+ xbt_die("no ptrace equivalent coded for this platform, stateful model-checking is impossible.");
#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);
+ XBT_DEBUG("%d ptrace correctly setup.", getpid());
}
void CheckerSide::setup_events(bool socket_only)
socket_event_ = event_new(
base, get_channel().get_socket(), EV_READ | EV_PERSIST,
[](evutil_socket_t, short events, void* arg) {
- auto checker = static_cast<simgrid::mc::CheckerSide*>(arg);
+ auto* checker = static_cast<simgrid::mc::CheckerSide*>(arg);
if (events == EV_READ) {
- std::array<char, MC_MESSAGE_LENGTH> buffer;
- ssize_t size = recv(checker->get_channel().get_socket(), buffer.data(), buffer.size(), MSG_DONTWAIT);
- if (size == -1) {
- XBT_ERROR("Channel::receive failure: %s", strerror(errno));
- if (errno != EAGAIN)
- throw simgrid::xbt::errno_error();
- }
-
- if (size == 0) // The app closed the socket. It must be dead by now.
- checker->handle_waitpid();
- else if (not checker->handle_message(buffer.data(), size))
- checker->break_loop();
+ do {
+ std::array<char, MC_MESSAGE_LENGTH> buffer;
+ ssize_t size = checker->get_channel().receive(buffer.data(), buffer.size(), MSG_DONTWAIT);
+ if (size == -1) {
+ XBT_ERROR("Channel::receive failure: %s", strerror(errno));
+ if (errno != EAGAIN)
+ throw simgrid::xbt::errno_error();
+ }
+
+ if (size == 0) // The app closed the socket. It must be dead by now.
+ checker->handle_waitpid();
+ else if (not checker->handle_message(buffer.data(), size)) {
+ checker->break_loop();
+ break;
+ }
+ } while (checker->get_channel().has_pending_data());
} else {
xbt_die("Unexpected event");
}
signal_event_ = event_new(
base, SIGCHLD, EV_SIGNAL | EV_PERSIST,
[](evutil_socket_t sig, short events, void* arg) {
- auto checker = static_cast<simgrid::mc::CheckerSide*>(arg);
+ auto* checker = static_cast<simgrid::mc::CheckerSide*>(arg);
if (events == EV_SIGNAL) {
if (sig == SIGCHLD)
checker->handle_waitpid();
}
/* When this constructor is called, no other checkerside exists */
-CheckerSide::CheckerSide(const std::vector<char*>& args, bool need_memory_info) : running_(true)
+CheckerSide::CheckerSide(const std::vector<char*>& args) : running_(true)
{
- // Create an AF_LOCAL socketpair used for exchanging messages between the model-checker process (ancestor)
+ XBT_DEBUG("Create a CheckerSide.");
+
+ // Create an AF_UNIX socketpair used for exchanging messages between the model-checker process (ancestor)
// and the application process (child)
int sockets[2];
- xbt_assert(socketpair(AF_LOCAL, SOCK_SEQPACKET | SOCK_CLOEXEC, 0, sockets) != -1, "Could not create socketpair: %s",
- strerror(errno));
+ xbt_assert(socketpair(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, sockets) != -1,
+ "Could not create socketpair: %s", strerror(errno));
pid_ = fork();
xbt_assert(pid_ >= 0, "Could not fork application process");
if (pid_ == 0) { // Child
::close(sockets[1]);
- run_child_process(sockets[0], args, need_memory_info); // We need ptrace if we need the mem info
+ run_child_process(sockets[0], args);
DIE_IMPOSSIBLE;
}
channel_.reset_socket(sockets[1]);
setup_events(false); /* we need a signal handler too */
- if (need_memory_info) {
-#if SIMGRID_HAVE_STATEFUL_MC
- // setup ptrace and sync with the app
- wait_application_process(pid_);
-
- // Request the initial memory on need
- channel_.send(MessageType::NEED_MEMINFO);
- s_mc_message_need_meminfo_reply_t answer;
- ssize_t answer_size = channel_.receive(answer);
- xbt_assert(answer_size != -1, "Could not receive message");
- xbt_assert(answer.type == MessageType::NEED_MEMINFO_REPLY,
- "The received message is not the NEED_MEMINFO_REPLY I was expecting but of type %s",
- to_c_str(answer.type));
- xbt_assert(answer_size == sizeof answer, "Broken message (size=%zd; expected %zu)", answer_size, sizeof answer);
-
- /* We now have enough info to create the memory address space */
- remote_memory_ = std::make_unique<simgrid::mc::RemoteProcessMemory>(pid_, answer.mmalloc_default_mdp);
-#else
- xbt_die("Cannot introspect memory without MC support");
-#endif
- }
-
wait_for_requests();
}
/* This constructor is called when cloning a checkerside to get its application to fork away */
CheckerSide::CheckerSide(int socket, CheckerSide* child_checker)
- : channel_(socket), running_(true), child_checker_(child_checker)
+ : channel_(socket, child_checker->channel_), running_(true), child_checker_(child_checker)
{
setup_events(true); // We already have a signal handled in that case
wait_for_requests();
}
-std::unique_ptr<CheckerSide> CheckerSide::clone(int master_socket)
+std::unique_ptr<CheckerSide> CheckerSide::clone(int master_socket, const std::string& master_socket_name)
{
- s_mc_message_int_t m = {};
- m.type = MessageType::FORK;
- m.value = getpid();
+ s_mc_message_fork_t m = {};
+ m.type = MessageType::FORK;
+ xbt_assert(master_socket_name.size() == MC_SOCKET_NAME_LEN);
+ std::copy_n(begin(master_socket_name), MC_SOCKET_NAME_LEN, begin(m.socket_name));
xbt_assert(get_channel().send(m) == 0, "Could not ask the app to fork on need.");
int sock = accept(master_socket, nullptr /* I know who's connecting*/, nullptr);
bool CheckerSide::handle_message(const char* buffer, ssize_t size)
{
s_mc_message_t base_message;
+ ssize_t consumed;
xbt_assert(size >= (ssize_t)sizeof(base_message), "Broken message. Got only %ld bytes.", size);
memcpy(&base_message, buffer, sizeof(base_message));
switch (base_message.type) {
- case MessageType::IGNORE_HEAP: {
-#if SIMGRID_HAVE_STATEFUL_MC
- if (remote_memory_ != nullptr) {
- s_mc_message_ignore_heap_t message;
- xbt_assert(size == sizeof(message), "Broken message");
- memcpy(&message, buffer, sizeof(message));
-
- IgnoredHeapRegion region;
- region.block = message.block;
- region.fragment = message.fragment;
- region.address = message.address;
- region.size = message.size;
- get_remote_memory()->ignore_heap(region);
- } else
-#endif
- XBT_INFO("Ignoring a IGNORE_HEAP message because we don't need to introspect memory.");
- break;
- }
-
- case MessageType::UNIGNORE_HEAP: {
-#if SIMGRID_HAVE_STATEFUL_MC
- if (remote_memory_ != nullptr) {
- s_mc_message_ignore_memory_t message;
- xbt_assert(size == sizeof(message), "Broken message");
- memcpy(&message, buffer, sizeof(message));
- get_remote_memory()->unignore_heap((void*)message.addr, message.size);
- } else
-#endif
- XBT_INFO("Ignoring an UNIGNORE_HEAP message because we don't need to introspect memory.");
- break;
- }
-
- case MessageType::IGNORE_MEMORY: {
-#if SIMGRID_HAVE_STATEFUL_MC
- if (remote_memory_ != nullptr) {
- s_mc_message_ignore_memory_t message;
- xbt_assert(size == sizeof(message), "Broken message");
- memcpy(&message, buffer, sizeof(message));
- get_remote_memory()->ignore_region(message.addr, message.size);
- } else
-#endif
- XBT_INFO("Ignoring an IGNORE_MEMORY message because we don't need to introspect memory.");
- break;
- }
-
- case MessageType::STACK_REGION: {
-#if SIMGRID_HAVE_STATEFUL_MC
- if (remote_memory_ != nullptr) {
- s_mc_message_stack_region_t message;
- xbt_assert(size == sizeof(message), "Broken message");
- memcpy(&message, buffer, sizeof(message));
- get_remote_memory()->stack_areas().push_back(message.stack_region);
- } else
-#endif
- XBT_INFO("Ignoring an STACK_REGION message because we don't need to introspect memory.");
- break;
- }
-
- case MessageType::REGISTER_SYMBOL: {
-#if SIMGRID_HAVE_STATEFUL_MC
- s_mc_message_register_symbol_t message;
- xbt_assert(size == sizeof(message), "Broken message");
- memcpy(&message, buffer, sizeof(message));
- xbt_assert(not message.callback, "Support for client-side function proposition is not implemented.");
- XBT_DEBUG("Received symbol: %s", message.name.data());
-
- LivenessChecker::automaton_register_symbol(*get_remote_memory(), message.name.data(), remote((int*)message.data));
-#else
- xbt_die("Please don't use liveness properties when MC is compiled out.");
-#endif
- break;
- }
case MessageType::WAITING:
+ consumed = sizeof(s_mc_message_t);
+ if (size > consumed) {
+ XBT_DEBUG("%d reinject %d bytes after a %s message", getpid(), (int)(size - consumed),
+ to_c_str(base_message.type));
+ channel_.reinject(&buffer[consumed], size - consumed);
+ }
+
return false;
case MessageType::ASSERTION_FAILED:
+ // report_assertion_failure() is NORETURN, but it may change when we report more than one error per run,
+ // so please keep the consumed computation even if clang-static detects it as a dead affectation.
+ consumed = sizeof(s_mc_message_t);
Exploration::get_instance()->report_assertion_failure();
break;
default:
xbt_die("Unexpected message from the application");
}
+ if (size > consumed) {
+ XBT_DEBUG("%d reinject %d bytes after a %s message", getpid(), (int)(size - consumed), to_c_str(base_message.type));
+ channel_.reinject(&buffer[consumed], size - consumed);
+ }
return true;
}
XBT_DEBUG("Resume the application");
if (get_channel().send(MessageType::CONTINUE) != 0)
throw xbt::errno_error();
- clear_memory_cache();
if (running())
dispatch_events();
}
-void CheckerSide::clear_memory_cache()
-{
-#if SIMGRID_HAVE_STATEFUL_MC
- if (remote_memory_)
- remote_memory_->clear_cache();
-#endif
-}
-
void CheckerSide::handle_dead_child(int status)
{
// From PTRACE_O_TRACEEXIT:
void CheckerSide::handle_waitpid()
{
- XBT_DEBUG("Check for wait event");
+ XBT_DEBUG("%d checks for wait event. %s", getpid(),
+ child_checker_ == nullptr ? "Wait directly." : "Ask our proxy to wait for its child.");
if (child_checker_ == nullptr) { // Wait directly
int status;
}
} else { // Ask our proxy to wait for us
-
s_mc_message_int_t request = {};
request.type = MessageType::WAIT_CHILD;
request.value = pid_;
