1 /* Copyright (c) 2015-2022. 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/api/RemoteApp.hpp"
7 #include "src/internal_config.h" // HAVE_SMPI
8 #include "src/mc/explo/Exploration.hpp"
9 #include "src/mc/mc_config.hpp"
11 #include "smpi/smpi.h"
12 #include "src/smpi/include/private.hpp"
15 #include "src/mc/api/State.hpp"
16 #include "src/mc/mc_config.hpp"
17 #include "src/mc/mc_exit.hpp"
18 #include "src/mc/mc_private.hpp"
20 #include "xbt/system_error.hpp"
23 #include <boost/tokenizer.hpp>
29 #include <sys/prctl.h>
32 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_Session, mc, "Model-checker session");
33 XBT_LOG_EXTERNAL_CATEGORY(mc_global);
35 static simgrid::config::Flag<std::string> _sg_mc_setenv{
36 "model-check/setenv", "Extra environment variables to pass to the child process (ex: 'AZE=aze;QWE=qwe').", "",
37 [](std::string_view value) {
38 xbt_assert(value.empty() || value.find('=', 0) != std::string_view::npos,
39 "The 'model-check/setenv' parameter must be like 'AZE=aze', but it does not contain an equal sign.");
42 namespace simgrid::mc {
44 static void run_child_process(int socket, const std::vector<char*>& args)
46 /* On startup, simix_global_init() calls simgrid::mc::Client::initialize(), which checks whether the MC_ENV_SOCKET_FD
47 * env variable is set. If so, MC mode is assumed, and the client is setup from its side
51 // Make sure we do not outlive our parent
54 xbt_assert(sigprocmask(SIG_SETMASK, &mask, nullptr) >= 0, "Could not unblock signals");
55 xbt_assert(prctl(PR_SET_PDEATHSIG, SIGHUP) == 0, "Could not PR_SET_PDEATHSIG");
58 // Remove CLOEXEC to pass the socket to the application
59 int fdflags = fcntl(socket, F_GETFD, 0);
60 xbt_assert(fdflags != -1 && fcntl(socket, F_SETFD, fdflags & ~FD_CLOEXEC) != -1,
61 "Could not remove CLOEXEC for socket");
63 setenv(MC_ENV_SOCKET_FD, std::to_string(socket).c_str(), 1);
65 /* Setup the tokenizer that parses the cfg:model-check/setenv parameter */
66 using Tokenizer = boost::tokenizer<boost::char_separator<char>>;
67 boost::char_separator<char> semicol_sep(";");
68 boost::char_separator<char> equal_sep("=");
69 Tokenizer token_vars(_sg_mc_setenv.get(), semicol_sep); /* Iterate over all FOO=foo parts */
70 for (const auto& token : token_vars) {
71 std::vector<std::string> kv;
72 Tokenizer token_kv(token, equal_sep);
73 for (const auto& t : token_kv) /* Iterate over 'FOO' and then 'foo' in that 'FOO=foo' */
75 xbt_assert(kv.size() == 2, "Parse error on 'model-check/setenv' value %s. Does it contain an equal sign?",
77 XBT_INFO("setenv '%s'='%s'", kv[0].c_str(), kv[1].c_str());
78 setenv(kv[0].c_str(), kv[1].c_str(), 1);
81 /* And now, exec the child process */
83 while (args[i] != nullptr && args[i][0] == '-')
86 xbt_assert(args[i] != nullptr,
87 "Unable to find a binary to exec on the command line. Did you only pass config flags?");
89 execvp(args[i], args.data() + i);
90 xbt_die("The model-checked process failed to exec(%s): %s", args[i], strerror(errno));
93 RemoteApp::RemoteApp(const std::vector<char*>& args)
96 smpi_init_options(); // only performed once
97 xbt_assert(smpi_cfg_privatization() != SmpiPrivStrategies::MMAP,
98 "Please use the dlopen privatization schema when model-checking SMPI code");
101 // Create an AF_LOCAL socketpair used for exchanging messages
102 // between the model-checker process (ourselves) and the model-checked
105 xbt_assert(socketpair(AF_LOCAL, SOCK_SEQPACKET | SOCK_CLOEXEC, 0, sockets) != -1, "Could not create socketpair");
108 xbt_assert(pid >= 0, "Could not fork model-checked process");
110 if (pid == 0) { // Child
112 run_child_process(sockets[0], args);
116 // Parent (model-checker):
119 xbt_assert(mc_model_checker == nullptr, "Did you manage to start the MC twice in this process?");
121 auto process = std::make_unique<simgrid::mc::RemoteProcess>(pid);
122 model_checker_ = std::make_unique<simgrid::mc::ModelChecker>(std::move(process), sockets[1]);
124 mc_model_checker = model_checker_.get();
125 model_checker_->start();
127 /* Take the initial snapshot */
128 model_checker_->wait_for_requests();
129 initial_snapshot_ = std::make_shared<simgrid::mc::Snapshot>(0);
132 RemoteApp::~RemoteApp()
134 initial_snapshot_ = nullptr;
135 if (model_checker_) {
136 model_checker_->shutdown();
137 model_checker_ = nullptr;
138 mc_model_checker = nullptr;
142 void RemoteApp::restore_initial_state() const
144 this->initial_snapshot_->restore(&model_checker_->get_remote_process());
147 unsigned long RemoteApp::get_maxpid() const
149 return model_checker_->get_remote_process().get_maxpid();
152 void RemoteApp::get_actors_status(std::map<aid_t, ActorState>& whereto) const
155 memset(&msg, 0, sizeof msg);
156 msg.type = simgrid::mc::MessageType::ACTORS_STATUS;
157 model_checker_->channel().send(msg);
159 s_mc_message_actors_status_answer_t answer;
160 ssize_t received = model_checker_->channel().receive(answer);
161 xbt_assert(received != -1, "Could not receive message");
162 xbt_assert(received == sizeof(answer) && answer.type == MessageType::ACTORS_STATUS_REPLY,
163 "Received unexpected message %s (%i, size=%i) "
164 "expected MessageType::ACTORS_STATUS_REPLY (%i, size=%i)",
165 to_c_str(answer.type), (int)answer.type, (int)received, (int)MessageType::ACTORS_STATUS_REPLY,
166 (int)sizeof(answer));
168 std::vector<s_mc_message_actors_status_one_t> status(answer.count);
169 if (answer.count > 0) {
170 size_t size = status.size() * sizeof(s_mc_message_actors_status_one_t);
171 received = model_checker_->channel().receive(status.data(), size);
172 xbt_assert(static_cast<size_t>(received) == size);
176 for (auto const& actor : status)
177 whereto.try_emplace(actor.aid, actor.aid, actor.enabled, actor.max_considered);
180 void RemoteApp::check_deadlock() const
182 xbt_assert(model_checker_->channel().send(MessageType::DEADLOCK_CHECK) == 0, "Could not check deadlock state");
183 s_mc_message_int_t message;
184 ssize_t s = model_checker_->channel().receive(message);
185 xbt_assert(s != -1, "Could not receive message");
186 xbt_assert(s == sizeof(message) && message.type == MessageType::DEADLOCK_CHECK_REPLY,
187 "Received unexpected message %s (%i, size=%i) "
188 "expected MessageType::DEADLOCK_CHECK_REPLY (%i, size=%i)",
189 to_c_str(message.type), (int)message.type, (int)s, (int)MessageType::DEADLOCK_CHECK_REPLY,
190 (int)sizeof(message));
192 if (message.value != 0) {
193 XBT_CINFO(mc_global, "**************************");
194 XBT_CINFO(mc_global, "*** DEADLOCK DETECTED ***");
195 XBT_CINFO(mc_global, "**************************");
196 XBT_CINFO(mc_global, "Counter-example execution trace:");
197 for (auto const& frame : model_checker_->get_exploration()->get_textual_trace())
198 XBT_CINFO(mc_global, " %s", frame.c_str());
199 XBT_CINFO(mc_global, "Path = %s", model_checker_->get_exploration()->get_record_trace().to_string().c_str());
200 model_checker_->get_exploration()->log_state();
201 throw DeadlockError();
204 } // namespace simgrid::mc