#include "src/kernel/actor/SimcallObserver.hpp"
#include "src/mc/mc_base.hpp"
#include "src/mc/mc_config.hpp"
-#if SIMGRID_HAVE_STATEFUL_MC
-#include "src/mc/sosp/RemoteProcessMemory.hpp"
-#endif
+#include "src/mc/mc_environ.h"
#if HAVE_SMPI
#include "src/smpi/include/private.hpp"
#endif
#include <simgrid/modelchecker.h>
#include <cerrno>
+#include <cinttypes>
#include <cstdio> // setvbuf
#include <cstdlib>
#include <memory>
if (std::getenv(MC_ENV_SOCKET_FD) == nullptr) // We are not in MC mode: don't initialize the MC world
return nullptr;
- XBT_DEBUG("Initialize the MC world. MC_NEED_PTRACE=%s", std::getenv("MC_NEED_PTRACE"));
+ XBT_DEBUG("Initialize the MC world.");
simgrid::mc::set_model_checking_mode(ModelCheckingMode::APP_SIDE);
int fd = xbt_str_parse_int(fd_env, "Not a number in variable '" MC_ENV_SOCKET_FD "'");
XBT_DEBUG("Model-checked application found socket FD %i", fd);
- // Check the socket type/validity:
- int type;
- socklen_t socklen = sizeof(type);
- xbt_assert(getsockopt(fd, SOL_SOCKET, SO_TYPE, &type, &socklen) == 0, "Could not check socket type");
- xbt_assert(type == SOCK_SEQPACKET, "Unexpected socket type %i", type);
- XBT_DEBUG("Model-checked application found expected socket type");
-
instance_ = std::make_unique<simgrid::mc::AppSide>(fd);
- // Wait for the model-checker:
- if (getenv("MC_NEED_PTRACE") != nullptr) {
- errno = 0;
-#if defined __linux__
- ptrace(PTRACE_TRACEME, 0, nullptr, nullptr);
-#elif defined BSD
- ptrace(PT_TRACE_ME, 0, nullptr, 0);
-#else
- xbt_die("no ptrace equivalent coded for this platform, please don't use the liveness checker here.");
-#endif
-
- xbt_assert(errno == 0 && raise(SIGSTOP) == 0, "Could not wait for the model-checker (errno = %d: %s)", errno,
- strerror(errno));
- }
-
instance_->handle_messages();
return instance_.get();
}
s_mc_message_int_t answer = {};
answer.type = MessageType::DEADLOCK_CHECK_REPLY;
answer.value = deadlock;
- xbt_assert(channel_.send(answer) == 0, "Could not send response");
+ xbt_assert(channel_.send(answer) == 0, "Could not send response: %s", strerror(errno));
}
void AppSide::handle_simcall_execute(const s_mc_message_simcall_execute_t* message) const
{
// The client may send some messages to the server while processing the transition
actor->simcall_handle(message->times_considered_);
// Say the server that the transition is over and that it should proceed
- xbt_assert(channel_.send(MessageType::WAITING) == 0, "Could not send MESSAGE_WAITING to model-checker");
+ xbt_assert(channel_.send(MessageType::WAITING) == 0, "Could not send MESSAGE_WAITING to model-checker: %s",
+ strerror(errno));
// Finish the RPC from the server: return a serialized observer, to build a Transition on Checker side
s_mc_message_simcall_execute_answer_t answer = {};
answer.buffer.back() = '\0';
XBT_DEBUG("send SIMCALL_EXECUTE_ANSWER(%s) ~> '%s'", actor->get_cname(), str.c_str());
- xbt_assert(channel_.send(answer) == 0, "Could not send response");
+ xbt_assert(channel_.send(answer) == 0, "Could not send response: %s", strerror(errno));
}
void AppSide::handle_finalize(const s_mc_message_int_t* msg) const
#endif
}
coverage_checkpoint();
- xbt_assert(channel_.send(MessageType::FINALIZE_REPLY) == 0, "Could not answer to FINALIZE");
+ xbt_assert(channel_.send(MessageType::FINALIZE_REPLY) == 0, "Could not answer to FINALIZE: %s", strerror(errno));
std::fflush(stdout);
if (terminate_asap)
::_Exit(0);
}
-void AppSide::handle_fork(const s_mc_message_int_t* msg)
+void AppSide::handle_fork(const s_mc_message_fork_t* msg)
{
- int pid = fork();
+ int status;
+ int pid;
+ /* Reap any zombie child, saving its status for later use in AppSide::handle_wait_child() */
+ while ((pid = waitpid(-1, &status, WNOHANG)) > 0)
+ child_statuses_[pid] = status;
+
+ pid = fork();
xbt_assert(pid >= 0, "Could not fork application sub-process: %s.", strerror(errno));
if (pid == 0) { // Child
- int sock = socket(AF_LOCAL, SOCK_SEQPACKET | SOCK_CLOEXEC, 0);
+ int sock = 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);
struct sockaddr_un addr = {};
- addr.sun_family = AF_LOCAL;
- snprintf(addr.sun_path, 64, "/tmp/simgrid-mc-%lu", msg->value);
- auto addr_size = offsetof(struct sockaddr_un, sun_path) + strlen(addr.sun_path);
+ addr.sun_family = AF_UNIX;
+ std::copy_n(begin(msg->socket_name), MC_SOCKET_NAME_LEN, addr.sun_path);
- xbt_assert(connect(sock, (struct sockaddr*)&addr, addr_size) >= 0,
- "Cannot connect to Checker on /tmp/simgrid-mc-%lu: %s.", msg->value, strerror(errno));
+ xbt_assert(connect(sock, (struct sockaddr*)&addr, sizeof addr) >= 0, "Cannot connect to Checker on %c%s: %s.",
+ (addr.sun_path[0] ? addr.sun_path[0] : '@'), addr.sun_path + 1, strerror(errno));
channel_.reset_socket(sock);
answer.value = getpid();
xbt_assert(channel_.send(answer) == 0, "Could not send response to WAIT_CHILD_REPLY: %s", strerror(errno));
} else {
- XBT_DEBUG("App %d forks subprocess %d.", getpid(), pid);
+ XBT_VERB("App %d forks subprocess %d.", getpid(), pid);
}
}
void AppSide::handle_wait_child(const s_mc_message_int_t* msg)
{
int status;
errno = 0;
- waitpid(msg->value, &status, 0);
+ if (auto search = child_statuses_.find(msg->value); search != child_statuses_.end()) {
+ status = search->second;
+ child_statuses_.erase(search); // We only need this info once
+ } else {
+ waitpid(msg->value, &status, 0);
+ }
xbt_assert(errno == 0, "Cannot wait on behalf of the checker: %s.", strerror(errno));
s_mc_message_int_t answer = {};
answer.value = status;
xbt_assert(channel_.send(answer) == 0, "Could not send response to WAIT_CHILD: %s", strerror(errno));
}
-void AppSide::handle_need_meminfo()
-{
-#if SIMGRID_HAVE_STATEFUL_MC
- this->need_memory_info_ = true;
- s_mc_message_need_meminfo_reply_t answer = {};
- answer.type = MessageType::NEED_MEMINFO_REPLY;
- answer.mmalloc_default_mdp = mmalloc_get_current_heap();
- xbt_assert(channel_.send(answer) == 0, "Could not send response to the request for meminfo.");
-#else
- xbt_die("SimGrid was compiled without MC suppport, so liveness and similar features are not available.");
-#endif
-}
void AppSide::handle_actors_status() const
{
auto const& actor_list = kernel::EngineImpl::get_instance()->get_actor_list();
std::vector<s_mc_message_actors_status_one_t> status;
for (auto const& [aid, actor] : actor_list) {
+ xbt_assert(actor);
+ xbt_assert(actor->simcall_.observer_, "simcall %s in actor %s has no observer.", actor->simcall_.get_cname(),
+ actor->get_cname());
s_mc_message_actors_status_one_t one = {};
one.type = MessageType::ACTORS_STATUS_REPLY_TRANSITION;
one.aid = aid;
answer.type = MessageType::ACTORS_STATUS_REPLY_COUNT;
answer.count = static_cast<int>(status.size());
- xbt_assert(channel_.send(answer) == 0, "Could not send ACTORS_STATUS_REPLY msg");
+ xbt_assert(channel_.send(answer) == 0, "Could not send ACTORS_STATUS_REPLY msg: %s", strerror(errno));
if (answer.count > 0) {
size_t size = status.size() * sizeof(s_mc_message_actors_status_one_t);
- xbt_assert(channel_.send(status.data(), size) == 0, "Could not send ACTORS_STATUS_REPLY data");
+ xbt_assert(channel_.send(status.data(), size) == 0, "Could not send ACTORS_STATUS_REPLY data: %s", strerror(errno));
}
// Serialize each transition to describe what each actor is doing
XBT_DEBUG("Deliver ACTOR_TRANSITION_PROBE payload");
for (const auto& actor_status : status) {
- if (not actor_status.enabled)
- continue;
-
const auto& actor = actor_list.at(actor_status.aid);
const int max_considered = actor_status.max_considered;
strncpy(probe.buffer.data(), str.c_str(), probe.buffer.size() - 1);
probe.buffer.back() = '\0';
- xbt_assert(channel_.send(probe) == 0, "Could not send ACTOR_TRANSITION_PROBE payload");
+ XBT_DEBUG("send ACTOR_TRANSITION_PROBE(%s) ~> '%s'", actor->get_cname(), str.c_str());
+ xbt_assert(channel_.send(probe) == 0, "Could not send ACTOR_TRANSITION_PROBE payload: %s", strerror(errno));
}
// NOTE: We do NOT need to reset `times_considered` for each actor's
// simcall observer here to the "original" value (i.e. the value BEFORE
s_mc_message_int_t answer = {};
answer.type = MessageType::ACTORS_MAXPID_REPLY;
answer.value = kernel::actor::ActorImpl::get_maxpid();
- xbt_assert(channel_.send(answer) == 0, "Could not send response");
+ xbt_assert(channel_.send(answer) == 0, "Could not send response: %s", strerror(errno));
}
#define assert_msg_size(_name_, _type_) \
XBT_DEBUG("Socket closed on the Checker side, bailing out.");
::_Exit(0); // Nobody's listening to that process anymore => exit as quickly as possible.
}
- xbt_assert(received_size >= 0, "Could not receive commands from the model-checker");
+ xbt_assert(received_size >= 0, "Could not receive commands from the model-checker: %s", strerror(errno));
xbt_assert(static_cast<size_t>(received_size) >= sizeof(s_mc_message_t), "Cannot handle short message (size=%zd)",
received_size);
break;
case MessageType::FORK:
- assert_msg_size("FORK", s_mc_message_int_t);
- handle_fork((s_mc_message_int_t*)message_buffer.data());
+ assert_msg_size("FORK", s_mc_message_fork_t);
+ handle_fork((s_mc_message_fork_t*)message_buffer.data());
break;
case MessageType::WAIT_CHILD:
handle_wait_child((s_mc_message_int_t*)message_buffer.data());
break;
- case MessageType::NEED_MEMINFO:
- assert_msg_size("NEED_MEMINFO", s_mc_message_t);
- handle_need_meminfo();
- break;
-
case MessageType::ACTORS_STATUS:
assert_msg_size("ACTORS_STATUS", s_mc_message_t);
handle_actors_status();
void AppSide::main_loop()
{
simgrid::mc::processes_time.resize(simgrid::kernel::actor::ActorImpl::get_maxpid());
- MC_ignore_heap(simgrid::mc::processes_time.data(),
- simgrid::mc::processes_time.size() * sizeof(simgrid::mc::processes_time[0]));
sthread_disable();
coverage_checkpoint();
sthread_enable();
while (true) {
simgrid::mc::execute_actors();
- xbt_assert(channel_.send(MessageType::WAITING) == 0, "Could not send WAITING message to model-checker");
+ xbt_assert(channel_.send(MessageType::WAITING) == 0, "Could not send WAITING message to model-checker: %s",
+ strerror(errno));
this->handle_messages();
}
}
void AppSide::report_assertion_failure()
{
- xbt_assert(channel_.send(MessageType::ASSERTION_FAILED) == 0, "Could not send assertion to model-checker");
+ xbt_assert(channel_.send(MessageType::ASSERTION_FAILED) == 0, "Could not send assertion to model-checker: %s",
+ strerror(errno));
this->handle_messages();
}
-void AppSide::ignore_memory(void* addr, std::size_t size) const
-{
- if (not MC_is_active() || not need_memory_info_)
- return;
-
-#if SIMGRID_HAVE_STATEFUL_MC
- s_mc_message_ignore_memory_t message = {};
- message.type = MessageType::IGNORE_MEMORY;
- message.addr = (std::uintptr_t)addr;
- message.size = size;
- xbt_assert(channel_.send(message) == 0, "Could not send IGNORE_MEMORY message to model-checker");
-#else
- xbt_die("Cannot really call ignore_heap() in non-SIMGRID_MC mode.");
-#endif
-}
-
-void AppSide::ignore_heap(void* address, std::size_t size) const
-{
- if (not MC_is_active() || not need_memory_info_)
- return;
-
-#if SIMGRID_HAVE_STATEFUL_MC
- const s_xbt_mheap_t* heap = mmalloc_get_current_heap();
-
- s_mc_message_ignore_heap_t message = {};
- message.type = MessageType::IGNORE_HEAP;
- message.address = address;
- message.size = size;
- message.block = ((char*)address - (char*)heap->heapbase) / BLOCKSIZE + 1;
- if (heap->heapinfo[message.block].type == 0) {
- message.fragment = -1;
- heap->heapinfo[message.block].busy_block.ignore++;
- } else {
- message.fragment = (ADDR2UINT(address) % BLOCKSIZE) >> heap->heapinfo[message.block].type;
- heap->heapinfo[message.block].busy_frag.ignore[message.fragment]++;
- }
-
- xbt_assert(channel_.send(message) == 0, "Could not send ignored region to MCer");
-#else
- xbt_die("Cannot really call ignore_heap() in non-SIMGRID_MC mode.");
-#endif
-}
-
-void AppSide::unignore_heap(void* address, std::size_t size) const
-{
- if (not MC_is_active() || not need_memory_info_)
- return;
-
-#if SIMGRID_HAVE_STATEFUL_MC
- s_mc_message_ignore_memory_t message = {};
- message.type = MessageType::UNIGNORE_HEAP;
- message.addr = (std::uintptr_t)address;
- message.size = size;
- xbt_assert(channel_.send(message) == 0, "Could not send IGNORE_HEAP message to model-checker");
-#else
- xbt_die("Cannot really call unignore_heap() in non-SIMGRID_MC mode.");
-#endif
-}
-
-void AppSide::declare_symbol(const char* name, int* value) const
-{
- if (not MC_is_active() || not need_memory_info_) {
- XBT_CRITICAL("Ignore AppSide::declare_symbol(%s)", name);
- return;
- }
-
-#if SIMGRID_HAVE_STATEFUL_MC
- s_mc_message_register_symbol_t message = {};
- message.type = MessageType::REGISTER_SYMBOL;
- xbt_assert(strlen(name) + 1 <= message.name.size(), "Symbol is too long");
- strncpy(message.name.data(), name, message.name.size() - 1);
- message.callback = nullptr;
- message.data = value;
- xbt_assert(channel_.send(message) == 0, "Could send REGISTER_SYMBOL message to model-checker");
-#else
- xbt_die("Cannot really call declare_symbol() in non-SIMGRID_MC mode.");
-#endif
-}
-
-/** Register a stack in the model checker
- *
- * The stacks are allocated in the heap. The MC handle them specifically
- * when we analyze/compare the content of the heap so it must be told where
- * they are with this function.
- */
-void AppSide::declare_stack(void* stack, size_t size, ucontext_t* context) const
-{
- if (not MC_is_active() || not need_memory_info_)
- return;
-
-#if SIMGRID_HAVE_STATEFUL_MC
- const s_xbt_mheap_t* heap = mmalloc_get_current_heap();
-
- s_stack_region_t region = {};
- region.address = stack;
- region.context = context;
- region.size = size;
- region.block = ((char*)stack - (char*)heap->heapbase) / BLOCKSIZE + 1;
-
- s_mc_message_stack_region_t message = {};
- message.type = MessageType::STACK_REGION;
- message.stack_region = region;
- xbt_assert(channel_.send(message) == 0, "Could not send STACK_REGION to model-checker");
-#else
- xbt_die("Cannot really call declare_stack() in non-SIMGRID_MC mode.");
-#endif
-}
} // namespace simgrid::mc
