1 /* Copyright (c) 2015-2023. The SimGrid Team. All rights reserved. */
3 /* This program is free software; you can redistribute it and/or modify it
4 * under the terms of the license (GNU LGPL) which comes with this package. */
6 #include "src/mc/remote/AppSide.hpp"
7 #include "simgrid/s4u/Host.hpp"
8 #include "src/internal_config.h"
9 #include "src/kernel/EngineImpl.hpp"
10 #include "src/kernel/actor/ActorImpl.hpp"
11 #include "src/kernel/actor/SimcallObserver.hpp"
12 #include "src/mc/mc_base.hpp"
13 #include "src/mc/mc_config.hpp"
14 #include "src/mc/sosp/RemoteProcessMemory.hpp"
16 #include "src/smpi/include/private.hpp"
18 #include "src/sthread/sthread.h"
19 #include "src/xbt/coverage.h"
21 #include <simgrid/modelchecker.h>
24 #include <cstdio> // setvbuf
28 #include <sys/ptrace.h>
29 #include <sys/socket.h>
30 #include <sys/types.h>
32 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_client, mc, "MC client logic");
33 XBT_LOG_EXTERNAL_CATEGORY(mc_global);
35 namespace simgrid::mc {
37 std::unique_ptr<AppSide> AppSide::instance_;
39 AppSide* AppSide::initialize()
41 if (not std::getenv(MC_ENV_SOCKET_FD)) // We are not in MC mode: don't initialize the MC world
44 // Do not break if we are called multiple times:
46 return instance_.get();
48 simgrid::mc::model_checking_mode = ModelCheckingMode::APP_SIDE;
50 setvbuf(stdout, nullptr, _IOLBF, 0);
52 // Fetch socket from MC_ENV_SOCKET_FD:
53 const char* fd_env = std::getenv(MC_ENV_SOCKET_FD);
54 int fd = xbt_str_parse_int(fd_env, "Not a number in variable '" MC_ENV_SOCKET_FD "'");
55 XBT_DEBUG("Model-checked application found socket FD %i", fd);
57 // Check the socket type/validity:
59 socklen_t socklen = sizeof(type);
60 xbt_assert(getsockopt(fd, SOL_SOCKET, SO_TYPE, &type, &socklen) == 0, "Could not check socket type");
61 xbt_assert(type == SOCK_SEQPACKET, "Unexpected socket type %i", type);
62 XBT_DEBUG("Model-checked application found expected socket type");
64 instance_ = std::make_unique<simgrid::mc::AppSide>(fd);
66 // Wait for the model-checker:
69 ptrace(PTRACE_TRACEME, 0, nullptr, nullptr);
71 ptrace(PT_TRACE_ME, 0, nullptr, 0);
73 #error "no ptrace equivalent coded for this platform"
75 xbt_assert(errno == 0 && raise(SIGSTOP) == 0, "Could not wait for the model-checker (errno = %d: %s)", errno,
78 instance_->handle_messages();
79 return instance_.get();
82 void AppSide::handle_deadlock_check(const s_mc_message_t*) const
84 const auto* engine = kernel::EngineImpl::get_instance();
85 const auto& actor_list = engine->get_actor_list();
86 bool deadlock = not actor_list.empty() && std::none_of(begin(actor_list), end(actor_list), [](const auto& kv) {
87 return mc::actor_is_enabled(kv.second);
91 XBT_CINFO(mc_global, "**************************");
92 XBT_CINFO(mc_global, "*** DEADLOCK DETECTED ***");
93 XBT_CINFO(mc_global, "**************************");
94 engine->display_all_actor_status();
97 s_mc_message_int_t answer = {};
98 answer.type = MessageType::DEADLOCK_CHECK_REPLY;
99 answer.value = deadlock;
100 xbt_assert(channel_.send(answer) == 0, "Could not send response");
102 void AppSide::handle_simcall_execute(const s_mc_message_simcall_execute_t* message) const
104 kernel::actor::ActorImpl* actor = kernel::EngineImpl::get_instance()->get_actor_by_pid(message->aid_);
105 xbt_assert(actor != nullptr, "Invalid pid %ld", message->aid_);
107 // The client may send some messages to the server while processing the transition
108 actor->simcall_handle(message->times_considered_);
109 // Say the server that the transition is over and that it should proceed
110 xbt_assert(channel_.send(MessageType::WAITING) == 0, "Could not send MESSAGE_WAITING to model-checker");
112 // Finish the RPC from the server: return a serialized observer, to build a Transition on Checker side
113 s_mc_message_simcall_execute_answer_t answer = {};
114 answer.type = MessageType::SIMCALL_EXECUTE_ANSWER;
115 std::stringstream stream;
116 if (actor->simcall_.observer_ != nullptr) {
117 actor->simcall_.observer_->serialize(stream);
119 stream << (short)mc::Transition::Type::UNKNOWN;
121 std::string str = stream.str();
122 xbt_assert(str.size() + 1 <= answer.buffer.size(),
123 "The serialized simcall is too large for the buffer. Please fix the code.");
124 strncpy(answer.buffer.data(), str.c_str(), answer.buffer.size() - 1);
125 answer.buffer.back() = '\0';
127 XBT_DEBUG("send SIMCALL_EXECUTE_ANSWER(%s) ~> '%s'", actor->get_cname(), str.c_str());
128 xbt_assert(channel_.send(answer) == 0, "Could not send response");
131 void AppSide::handle_finalize(const s_mc_message_int_t* msg) const
133 bool terminate_asap = msg->value;
134 XBT_DEBUG("Finalize (terminate = %d)", (int)terminate_asap);
135 if (not terminate_asap) {
136 if (XBT_LOG_ISENABLED(mc_client, xbt_log_priority_debug))
137 kernel::EngineImpl::get_instance()->display_all_actor_status();
139 XBT_DEBUG("Smpi_enabled: %d", SMPI_is_inited());
140 if (SMPI_is_inited())
144 coverage_checkpoint();
145 xbt_assert(channel_.send(MessageType::FINALIZE_REPLY) == 0, "Could not answer to FINALIZE");
150 void AppSide::handle_initial_addresses() const
152 s_mc_message_initial_addresses_reply_t answer = {};
153 answer.type = MessageType::INITIAL_ADDRESSES_REPLY;
154 answer.mmalloc_default_mdp = mmalloc_get_current_heap();
155 xbt_assert(channel_.send(answer) == 0, "Could not send response with initial addresses.");
157 void AppSide::handle_actors_status() const
159 auto const& actor_list = kernel::EngineImpl::get_instance()->get_actor_list();
160 const int num_actors = actor_list.size();
161 XBT_DEBUG("Serialize the actors to answer ACTORS_STATUS from the checker. %d actors to go.", num_actors);
163 std::vector<s_mc_message_actors_status_one_t> status(num_actors);
165 int total_transitions = 0;
167 for (auto const& [aid, actor] : actor_list) {
169 status[i].enabled = mc::actor_is_enabled(actor);
170 status[i].max_considered = actor->simcall_.observer_->get_max_consider();
171 status[i].n_transitions = mc::actor_is_enabled(actor) ? status[i].max_considered : 0;
172 total_transitions += status[i].n_transitions;
176 struct s_mc_message_actors_status_answer_t answer = {};
177 answer.type = MessageType::ACTORS_STATUS_REPLY;
178 answer.count = num_actors;
179 answer.transition_count = total_transitions;
181 xbt_assert(channel_.send(answer) == 0, "Could not send ACTORS_STATUS_REPLY msg");
182 if (answer.count > 0) {
183 size_t size = status.size() * sizeof(s_mc_message_actors_status_one_t);
184 xbt_assert(channel_.send(status.data(), size) == 0, "Could not send ACTORS_STATUS_REPLY data");
187 // Serialize each transition to describe what each actor is doing
188 if (total_transitions > 0) {
189 std::vector<s_mc_message_simcall_probe_one_t> probes(total_transitions);
190 auto probes_iter = probes.begin();
192 for (const auto& actor_status : status) {
193 if (not actor_status.enabled)
196 const auto& actor = actor_list.at(actor_status.aid);
197 const int max_considered = actor_status.max_considered;
199 for (int times_considered = 0; times_considered < max_considered; times_considered++, probes_iter++) {
200 std::stringstream stream;
201 s_mc_message_simcall_probe_one_t& probe = *probes_iter;
203 if (actor->simcall_.observer_ != nullptr) {
204 actor->simcall_.observer_->prepare(times_considered);
205 actor->simcall_.observer_->serialize(stream);
207 stream << (short)mc::Transition::Type::UNKNOWN;
210 std::string str = stream.str();
211 xbt_assert(str.size() + 1 <= probe.buffer.size(),
212 "The serialized transition is too large for the buffer. Please fix the code.");
213 strncpy(probe.buffer.data(), str.c_str(), probe.buffer.size() - 1);
214 probe.buffer.back() = '\0';
216 // NOTE: We do NOT need to reset `times_considered` for each actor's
217 // simcall observer here to the "original" value (i.e. the value BEFORE
218 // multiple prepare() calls were made for serialization purposes) since
219 // each SIMCALL_EXECUTE provides a `times_considered` to be used to prepare
220 // the transition before execution.
222 XBT_DEBUG("Deliver ACTOR_TRANSITION_PROBE payload");
224 for (const auto& probe : probes)
225 xbt_assert(channel_.send(probe) == 0, "Could not send ACTOR_TRANSITION_PROBE payload");
228 void AppSide::handle_actors_maxpid() const
230 s_mc_message_int_t answer = {};
231 answer.type = MessageType::ACTORS_MAXPID_REPLY;
232 answer.value = kernel::actor::ActorImpl::get_maxpid();
233 xbt_assert(channel_.send(answer) == 0, "Could not send response");
236 #define assert_msg_size(_name_, _type_) \
237 xbt_assert(received_size == sizeof(_type_), "Unexpected size for " _name_ " (%zd != %zu)", received_size, \
240 void AppSide::handle_messages() const
242 while (true) { // Until we get a CONTINUE message
243 XBT_DEBUG("Waiting messages from model-checker");
245 std::array<char, MC_MESSAGE_LENGTH> message_buffer;
246 ssize_t received_size = channel_.receive(message_buffer.data(), message_buffer.size());
248 xbt_assert(received_size >= 0, "Could not receive commands from the model-checker");
249 xbt_assert(static_cast<size_t>(received_size) >= sizeof(s_mc_message_t), "Cannot handle short message (size=%zd)",
252 const s_mc_message_t* message = (s_mc_message_t*)message_buffer.data();
253 switch (message->type) {
254 case MessageType::DEADLOCK_CHECK:
255 assert_msg_size("DEADLOCK_CHECK", s_mc_message_t);
256 handle_deadlock_check(message);
259 case MessageType::CONTINUE:
260 assert_msg_size("MESSAGE_CONTINUE", s_mc_message_t);
263 case MessageType::SIMCALL_EXECUTE:
264 assert_msg_size("SIMCALL_EXECUTE", s_mc_message_simcall_execute_t);
265 handle_simcall_execute((s_mc_message_simcall_execute_t*)message_buffer.data());
268 case MessageType::FINALIZE:
269 assert_msg_size("FINALIZE", s_mc_message_int_t);
270 handle_finalize((s_mc_message_int_t*)message_buffer.data());
273 case MessageType::INITIAL_ADDRESSES:
274 assert_msg_size("INITIAL_ADDRESSES", s_mc_message_t);
275 handle_initial_addresses();
278 case MessageType::ACTORS_STATUS:
279 assert_msg_size("ACTORS_STATUS", s_mc_message_t);
280 handle_actors_status();
283 case MessageType::ACTORS_MAXPID:
284 assert_msg_size("ACTORS_MAXPID", s_mc_message_t);
285 handle_actors_maxpid();
289 xbt_die("Received unexpected message %s (%i)", to_c_str(message->type), static_cast<int>(message->type));
295 void AppSide::main_loop() const
297 simgrid::mc::processes_time.resize(simgrid::kernel::actor::ActorImpl::get_maxpid());
298 MC_ignore_heap(simgrid::mc::processes_time.data(),
299 simgrid::mc::processes_time.size() * sizeof(simgrid::mc::processes_time[0]));
302 coverage_checkpoint();
305 simgrid::mc::execute_actors();
306 xbt_assert(channel_.send(MessageType::WAITING) == 0, "Could not send WAITING message to model-checker");
307 this->handle_messages();
311 void AppSide::report_assertion_failure() const
313 xbt_assert(channel_.send(MessageType::ASSERTION_FAILED) == 0, "Could not send assertion to model-checker");
314 this->handle_messages();
317 void AppSide::ignore_memory(void* addr, std::size_t size) const
319 if (not MC_is_active() || not need_memory_info_)
322 s_mc_message_ignore_memory_t message = {};
323 message.type = MessageType::IGNORE_MEMORY;
324 message.addr = (std::uintptr_t)addr;
326 xbt_assert(channel_.send(message) == 0, "Could not send IGNORE_MEMORY message to model-checker");
329 void AppSide::ignore_heap(void* address, std::size_t size) const
331 if (not MC_is_active() || not need_memory_info_)
334 const s_xbt_mheap_t* heap = mmalloc_get_current_heap();
336 s_mc_message_ignore_heap_t message = {};
337 message.type = MessageType::IGNORE_HEAP;
338 message.address = address;
340 message.block = ((char*)address - (char*)heap->heapbase) / BLOCKSIZE + 1;
341 if (heap->heapinfo[message.block].type == 0) {
342 message.fragment = -1;
343 heap->heapinfo[message.block].busy_block.ignore++;
345 message.fragment = (ADDR2UINT(address) % BLOCKSIZE) >> heap->heapinfo[message.block].type;
346 heap->heapinfo[message.block].busy_frag.ignore[message.fragment]++;
349 xbt_assert(channel_.send(message) == 0, "Could not send ignored region to MCer");
352 void AppSide::unignore_heap(void* address, std::size_t size) const
354 if (not MC_is_active() || not need_memory_info_)
357 s_mc_message_ignore_memory_t message = {};
358 message.type = MessageType::UNIGNORE_HEAP;
359 message.addr = (std::uintptr_t)address;
361 xbt_assert(channel_.send(message) == 0, "Could not send IGNORE_HEAP message to model-checker");
364 void AppSide::declare_symbol(const char* name, int* value) const
366 if (not MC_is_active() || not need_memory_info_)
369 s_mc_message_register_symbol_t message = {};
370 message.type = MessageType::REGISTER_SYMBOL;
371 xbt_assert(strlen(name) + 1 <= message.name.size(), "Symbol is too long");
372 strncpy(message.name.data(), name, message.name.size() - 1);
373 message.callback = nullptr;
374 message.data = value;
375 xbt_assert(channel_.send(message) == 0, "Could send REGISTER_SYMBOL message to model-checker");
378 /** Register a stack in the model checker
380 * The stacks are allocated in the heap. The MC handle them specifically
381 * when we analyze/compare the content of the heap so it must be told where
382 * they are with this function.
384 void AppSide::declare_stack(void* stack, size_t size, ucontext_t* context) const
386 if (not MC_is_active() || not need_memory_info_)
389 const s_xbt_mheap_t* heap = mmalloc_get_current_heap();
391 s_stack_region_t region = {};
392 region.address = stack;
393 region.context = context;
395 region.block = ((char*)stack - (char*)heap->heapbase) / BLOCKSIZE + 1;
397 s_mc_message_stack_region_t message = {};
398 message.type = MessageType::STACK_REGION;
399 message.stack_region = region;
400 xbt_assert(channel_.send(message) == 0, "Could not send STACK_REGION to model-checker");
402 } // namespace simgrid::mc