1 /* Copyright (c) 2008-2015. The SimGrid Team.
2 * All rights reserved. */
4 /* This program is free software; you can redistribute it and/or modify it
5 * under the terms of the license (GNU LGPL) which comes with this package. */
10 #include <sys/types.h>
12 #include <sys/socket.h>
13 #include <sys/signalfd.h>
14 #include <sys/ptrace.h>
17 #include <system_error>
20 #include <xbt/automaton.h>
21 #include <xbt/automaton.hpp>
22 #include <xbt/system_error.hpp>
24 #include "simgrid/sg_config.h"
26 #include "src/mc/ModelChecker.hpp"
27 #include "src/mc/PageStore.hpp"
28 #include "src/mc/ModelChecker.hpp"
29 #include "src/mc/mc_protocol.h"
30 #include "src/mc/mc_private.h"
31 #include "src/mc/mc_ignore.h"
32 #include "src/mc/mc_exit.h"
33 #include "src/mc/mc_liveness.h"
35 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_ModelChecker, mc, "ModelChecker");
37 ::simgrid::mc::ModelChecker* mc_model_checker = nullptr;
39 using simgrid::mc::remote;
41 // Hardcoded index for now:
42 #define SOCKET_FD_INDEX 0
43 #define SIGNAL_FD_INDEX 1
48 ModelChecker::ModelChecker(std::unique_ptr<Process> process) :
49 hostnames_(xbt_dict_new()),
51 process_(std::move(process)),
52 parent_snapshot_(nullptr)
57 ModelChecker::~ModelChecker()
59 xbt_dict_free(&this->hostnames_);
62 const char* ModelChecker::get_host_name(const char* hostname)
64 // Lookup the host name in the dictionary (or create it):
65 xbt_dictelm_t elt = xbt_dict_get_elm_or_null(this->hostnames_, hostname);
67 xbt_dict_set(this->hostnames_, hostname, nullptr, nullptr);
68 elt = xbt_dict_get_elm_or_null(this->hostnames_, hostname);
74 void ModelChecker::start()
76 const pid_t pid = process_->pid();
78 // Block SIGCHLD (this will be handled with accept/signalfd):
81 sigaddset(&set, SIGCHLD);
82 if (sigprocmask(SIG_BLOCK, &set, nullptr) == -1)
83 throw simgrid::xbt::errno_error(errno);
86 sigfillset(&full_set);
88 // Prepare data for poll:
90 struct pollfd* socket_pollfd = &fds_[SOCKET_FD_INDEX];
91 socket_pollfd->fd = process_->getChannel().getSocket();
92 socket_pollfd->events = POLLIN;
93 socket_pollfd->revents = 0;
95 int signal_fd = signalfd(-1, &set, 0);
97 throw simgrid::xbt::errno_error(errno);
99 struct pollfd* signalfd_pollfd = &fds_[SIGNAL_FD_INDEX];
100 signalfd_pollfd->fd = signal_fd;
101 signalfd_pollfd->events = POLLIN;
102 signalfd_pollfd->revents = 0;
104 XBT_DEBUG("Waiting for the model-checked process");
107 // The model-checked process SIGSTOP itself to signal it's ready:
108 pid_t res = waitpid(pid, &status, __WALL);
109 if (res < 0 || !WIFSTOPPED(status) || WSTOPSIG(status) != SIGSTOP)
110 xbt_die("Could not wait model-checked process");
114 /* Initialize statistics */
115 mc_stats = xbt_new0(s_mc_stats_t, 1);
116 mc_stats->state_size = 1;
118 if ((_sg_mc_dot_output_file != nullptr) && (_sg_mc_dot_output_file[0] != '\0'))
119 MC_init_dot_output();
122 //parmap = xbt_parmap_mc_new(xbt_os_get_numcores(), XBT_PARMAP_DEFAULT);
126 ptrace(PTRACE_SETOPTIONS, pid, nullptr, PTRACE_O_TRACEEXIT);
127 ptrace(PTRACE_CONT, pid, 0, 0);
130 static const std::pair<const char*, const char*> ignored_local_variables[] = {
131 std::pair<const char*, const char*>{ "e", "*" },
132 std::pair<const char*, const char*>{ "__ex_cleanup", "*" },
133 std::pair<const char*, const char*>{ "__ex_mctx_en", "*" },
134 std::pair<const char*, const char*>{ "__ex_mctx_me", "*" },
135 std::pair<const char*, const char*>{ "__xbt_ex_ctx_ptr", "*" },
136 std::pair<const char*, const char*>{ "_log_ev", "*" },
137 std::pair<const char*, const char*>{ "_throw_ctx", "*" },
138 std::pair<const char*, const char*>{ "ctx", "*" },
140 std::pair<const char*, const char*>{ "self", "simcall_BODY_mc_snapshot" },
141 std::pair<const char*, const char*>{ "next_context", "smx_ctx_sysv_suspend_serial" },
142 std::pair<const char*, const char*>{ "i", "smx_ctx_sysv_suspend_serial" },
144 /* Ignore local variable about time used for tracing */
145 std::pair<const char*, const char*>{ "start_time", "*" },
148 void ModelChecker::setup_ignore()
150 Process& process = this->process();
151 for (std::pair<const char*, const char*> const& var :
152 ignored_local_variables)
153 process.ignore_local_variable(var.first, var.second);
155 /* Static variable used for tracing */
156 process.ignore_global_variable("counter");
159 process.ignore_global_variable("smx_total_comms");
162 void ModelChecker::shutdown()
164 XBT_DEBUG("Shuting down model-checker");
166 simgrid::mc::Process* process = &this->process();
167 if (process->running()) {
168 XBT_DEBUG("Killing process");
169 kill(process->pid(), SIGTERM);
170 process->terminate();
174 void ModelChecker::resume(simgrid::mc::Process& process)
176 int res = process.getChannel().send(MC_MESSAGE_CONTINUE);
178 throw simgrid::xbt::errno_error(res);
179 process.cache_flags = (mc_process_cache_flags_t) 0;
183 void throw_socket_error(int fd)
186 socklen_t errlen = sizeof(error);
187 if (getsockopt(fd, SOL_SOCKET, SO_ERROR, (void *)&error, &errlen) == -1)
189 throw simgrid::xbt::errno_error(errno);
192 bool ModelChecker::handle_message(char* buffer, ssize_t size)
194 s_mc_message_t base_message;
195 if (size < (ssize_t) sizeof(base_message))
196 xbt_die("Broken message");
197 memcpy(&base_message, buffer, sizeof(base_message));
199 switch(base_message.type) {
201 case MC_MESSAGE_IGNORE_HEAP:
203 s_mc_ignore_heap_message_t message;
204 if (size != sizeof(message))
205 xbt_die("Broken messsage");
206 memcpy(&message, buffer, sizeof(message));
208 IgnoredHeapRegion region;
209 region.block = message.block;
210 region.fragment = message.fragment;
211 region.address = message.address;
212 region.size = message.size;
213 process().ignore_heap(region);
217 case MC_MESSAGE_UNIGNORE_HEAP:
219 s_mc_ignore_memory_message_t message;
220 if (size != sizeof(message))
221 xbt_die("Broken messsage");
222 memcpy(&message, buffer, sizeof(message));
223 process().unignore_heap(
224 (void *)(std::uintptr_t) message.addr, message.size);
228 case MC_MESSAGE_IGNORE_MEMORY:
230 s_mc_ignore_memory_message_t message;
231 if (size != sizeof(message))
232 xbt_die("Broken messsage");
233 memcpy(&message, buffer, sizeof(message));
234 this->process().ignore_region(message.addr, message.size);
238 case MC_MESSAGE_STACK_REGION:
240 s_mc_stack_region_message_t message;
241 if (size != sizeof(message))
242 xbt_die("Broken messsage");
243 memcpy(&message, buffer, sizeof(message));
244 this->process().stack_areas().push_back(message.stack_region);
248 case MC_MESSAGE_REGISTER_SYMBOL:
250 s_mc_register_symbol_message_t message;
251 if (size != sizeof(message))
252 xbt_die("Broken message");
253 memcpy(&message, buffer, sizeof(message));
254 if (message.callback)
255 xbt_die("Support for client-side function proposition is not implemented.");
256 XBT_DEBUG("Received symbol: %s", message.name);
258 if (simgrid::mc::property_automaton == nullptr)
259 simgrid::mc::property_automaton = xbt_automaton_new();
261 simgrid::mc::Process* process = &this->process();
262 simgrid::mc::RemotePtr<int> address
263 = simgrid::mc::remote((int*) message.data);
264 simgrid::xbt::add_proposition(simgrid::mc::property_automaton,
266 [process, address]() { return process->read(address); }
272 case MC_MESSAGE_WAITING:
275 case MC_MESSAGE_ASSERTION_FAILED:
276 MC_report_assertion_error();
277 this->exit(SIMGRID_MC_EXIT_SAFETY);
281 xbt_die("Unexpected message from model-checked application");
287 /** Terminate the model-checker aplication */
288 void ModelChecker::exit(int status)
290 // TODO, terminate the model checker politely instead of exiting rudel
291 if (process().running())
292 kill(process().pid(), SIGKILL);
296 bool ModelChecker::handle_events()
298 char buffer[MC_MESSAGE_LENGTH];
299 struct pollfd* socket_pollfd = &fds_[SOCKET_FD_INDEX];
300 struct pollfd* signalfd_pollfd = &fds_[SIGNAL_FD_INDEX];
302 while(poll(fds_, 2, -1) == -1) {
307 throw simgrid::xbt::errno_error(errno);
311 if (socket_pollfd->revents) {
312 if (socket_pollfd->revents & POLLIN) {
313 ssize_t size = process_->getChannel().receive(buffer, sizeof(buffer), false);
314 if (size == -1 && errno != EAGAIN)
315 throw simgrid::xbt::errno_error(errno);
316 return handle_message(buffer, size);
318 if (socket_pollfd->revents & POLLERR)
319 throw_socket_error(socket_pollfd->fd);
320 if (socket_pollfd->revents & POLLHUP)
321 xbt_die("Socket hang up?");
324 if (signalfd_pollfd->revents) {
325 if (signalfd_pollfd->revents & POLLIN) {
326 this->handle_signals();
329 if (signalfd_pollfd->revents & POLLERR)
330 throw_socket_error(signalfd_pollfd->fd);
331 if (signalfd_pollfd->revents & POLLHUP)
332 xbt_die("Signalfd hang up?");
338 void ModelChecker::loop()
340 while (this->process().running())
341 this->handle_events();
344 void ModelChecker::handle_signals()
346 struct signalfd_siginfo info;
347 struct pollfd* signalfd_pollfd = &fds_[SIGNAL_FD_INDEX];
349 ssize_t size = read(signalfd_pollfd->fd, &info, sizeof(info));
354 throw simgrid::xbt::errno_error(errno);
355 } else if (size != sizeof(info))
356 return throw std::runtime_error(
357 "Bad communication with model-checked application");
361 this->on_signal(&info);
364 void ModelChecker::handle_waitpid()
366 XBT_DEBUG("Check for wait event");
369 while ((pid = waitpid(-1, &status, WNOHANG)) != 0) {
371 if (errno == ECHILD) {
373 if (this->process().running())
374 xbt_die("Inconsistent state");
378 XBT_ERROR("Could not wait for pid");
379 throw simgrid::xbt::errno_error(errno);
383 if (pid == this->process().pid()) {
385 // From PTRACE_O_TRACEEXIT:
386 if (status>>8 == (SIGTRAP | (PTRACE_EVENT_EXIT<<8))) {
387 if (ptrace(PTRACE_GETEVENTMSG, this->process().pid(), 0, &status) == -1)
388 xbt_die("Could not get exit status");
389 if (WIFSIGNALED(status)) {
390 MC_report_crash(status);
391 mc_model_checker->exit(SIMGRID_MC_EXIT_PROGRAM_CRASH);
395 // We don't care about signals, just reinject them:
396 if (WIFSTOPPED(status)) {
397 XBT_DEBUG("Stopped with signal %i", (int) WSTOPSIG(status));
398 if (ptrace(PTRACE_CONT, this->process().pid(), 0, WSTOPSIG(status)) == -1)
399 xbt_die("Could not PTRACE_CONT");
402 else if (WIFEXITED(status) || WIFSIGNALED(status)) {
403 XBT_DEBUG("Child process is over");
404 this->process().terminate();
410 void ModelChecker::on_signal(const struct signalfd_siginfo* info)
412 switch(info->ssi_signo) {
414 this->handle_waitpid();
421 void ModelChecker::wait_client(simgrid::mc::Process& process)
423 this->resume(process);
424 while (this->process().running())
425 if (!this->handle_events())
429 void ModelChecker::simcall_handle(simgrid::mc::Process& process, unsigned long pid, int value)
431 s_mc_simcall_handle_message m;
432 memset(&m, 0, sizeof(m));
433 m.type = MC_MESSAGE_SIMCALL_HANDLE;
436 process.getChannel().send(m);
437 process.cache_flags = (mc_process_cache_flags_t) 0;
438 while (process.running())
439 if (!this->handle_events())