1 /* Copyright (c) 2014-2019. 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 #define _FILE_OFFSET_BITS 64 /* needed for pread_whole to work as expected on 32bits */
8 #include "src/mc/remote/RemoteClient.hpp"
10 #include "xbt/file.hpp"
12 #include "src/mc/mc_smx.hpp"
13 #include "src/mc/sosp/mc_snapshot.hpp"
16 #include <libunwind-ptrace.h>
17 #include <sys/mman.h> // PROT_*
19 using simgrid::mc::remote;
21 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_process, mc, "MC process information");
28 // List of library which memory segments are not considered:
29 static const std::vector<std::string> filtered_libraries = {
32 #elif defined __FreeBSD__
35 "libkvm", /* kernel data access library */
36 "libprocstat", /* process and file information retrieval */
37 "libthr", /* thread library */
40 "libargp", /* workarounds for glibc-less systems */
41 "libasan", /* gcc sanitizers */
44 "libboost_context-mt",
45 "libboost_stacktrace_backtrace",
81 "libtsan", /* gcc sanitizers */
82 "libubsan", /* gcc sanitizers */
89 static bool is_simgrid_lib(const std::string& libname)
91 return libname == "libsimgrid";
94 static bool is_filtered_lib(const std::string& libname)
96 return std::find(begin(filtered_libraries), end(filtered_libraries), libname) != end(filtered_libraries);
99 static std::string get_lib_name(const std::string& pathname)
101 std::string map_basename = simgrid::xbt::Path(pathname).get_base_name();
104 size_t pos = map_basename.rfind(".so");
105 if (pos != std::string::npos) {
106 // strip the extension (matching regex "\.so.*$")
107 libname.assign(map_basename, 0, pos);
109 // strip the version suffix (matching regex "-[.0-9-]*$")
111 pos = libname.rfind('-');
112 if (pos == std::string::npos || libname.find_first_not_of(".0123456789", pos + 1) != std::string::npos)
121 static ssize_t pread_whole(int fd, void* buf, size_t count, off_t offset)
123 char* buffer = (char*)buf;
124 ssize_t real_count = count;
126 ssize_t res = pread(fd, buffer, count, offset);
133 else if (errno != EINTR) {
134 perror("pread_whole");
141 static ssize_t pwrite_whole(int fd, const void* buf, size_t count, off_t offset)
143 const char* buffer = (const char*)buf;
144 ssize_t real_count = count;
146 ssize_t res = pwrite(fd, buffer, count, offset);
153 else if (errno != EINTR)
159 static pthread_once_t zero_buffer_flag = PTHREAD_ONCE_INIT;
160 static const void* zero_buffer;
161 static const size_t zero_buffer_size = 10 * 4096;
163 static void zero_buffer_init()
165 int fd = open("/dev/zero", O_RDONLY);
167 xbt_die("Could not open /dev/zero");
168 zero_buffer = mmap(nullptr, zero_buffer_size, PROT_READ, MAP_SHARED, fd, 0);
169 if (zero_buffer == MAP_FAILED)
170 xbt_die("Could not map the zero buffer");
174 int open_vm(pid_t pid, int flags)
176 const size_t buffer_size = 30;
177 char buffer[buffer_size];
178 int res = snprintf(buffer, buffer_size, "/proc/%lli/mem", (long long)pid);
179 if (res < 0 || (size_t)res >= buffer_size) {
180 errno = ENAMETOOLONG;
183 return open(buffer, flags);
188 RemoteClient::RemoteClient(pid_t pid, int sockfd) : AddressSpace(this), pid_(pid), channel_(sockfd), running_(true)
192 void RemoteClient::init()
194 this->memory_map_ = simgrid::xbt::get_memory_map(this->pid_);
195 this->init_memory_map_info();
197 int fd = open_vm(this->pid_, O_RDWR);
199 xbt_die("Could not open file for process virtual address space");
200 this->memory_file = fd;
202 // Read std_heap (is a struct mdesc*):
203 simgrid::mc::Variable* std_heap_var = this->find_variable("__mmalloc_default_mdp");
204 if (not std_heap_var)
205 xbt_die("No heap information in the target process");
206 if (not std_heap_var->address)
207 xbt_die("No constant address for this variable");
208 this->read_bytes(&this->heap_address, sizeof(mdesc*), remote(std_heap_var->address),
209 simgrid::mc::ProcessIndexDisabled);
211 this->smx_actors_infos.clear();
212 this->smx_dead_actors_infos.clear();
213 this->unw_addr_space = simgrid::mc::UnwindContext::createUnwindAddressSpace();
214 this->unw_underlying_addr_space = simgrid::unw::create_addr_space();
215 this->unw_underlying_context = simgrid::unw::create_context(this->unw_underlying_addr_space, this->pid_);
218 RemoteClient::~RemoteClient()
220 if (this->memory_file >= 0)
221 close(this->memory_file);
223 if (this->unw_underlying_addr_space != unw_local_addr_space) {
224 if (this->unw_underlying_addr_space)
225 unw_destroy_addr_space(this->unw_underlying_addr_space);
226 if (this->unw_underlying_context)
227 _UPT_destroy(this->unw_underlying_context);
230 unw_destroy_addr_space(this->unw_addr_space);
233 /** Refresh the information about the process
235 * Do not use directly, this is used by the getters when appropriate
236 * in order to have fresh data.
238 void RemoteClient::refresh_heap()
240 // Read/dereference/refresh the std_heap pointer:
242 this->heap = std::unique_ptr<s_xbt_mheap_t>(new s_xbt_mheap_t());
243 this->read_bytes(this->heap.get(), sizeof(mdesc), remote(this->heap_address), simgrid::mc::ProcessIndexDisabled);
244 this->cache_flags_ |= RemoteClient::cache_heap;
247 /** Refresh the information about the process
249 * Do not use direclty, this is used by the getters when appropriate
250 * in order to have fresh data.
252 void RemoteClient::refresh_malloc_info()
254 // Refresh process->heapinfo:
255 if (this->cache_flags_ & RemoteClient::cache_malloc)
257 size_t count = this->heap->heaplimit + 1;
258 if (this->heap_info.size() < count)
259 this->heap_info.resize(count);
260 this->read_bytes(this->heap_info.data(), count * sizeof(malloc_info), remote(this->heap->heapinfo),
261 simgrid::mc::ProcessIndexDisabled);
262 this->cache_flags_ |= RemoteClient::cache_malloc;
265 /** @brief Finds the range of the different memory segments and binary paths */
266 void RemoteClient::init_memory_map_info()
268 XBT_DEBUG("Get debug information ...");
269 this->maestro_stack_start_ = nullptr;
270 this->maestro_stack_end_ = nullptr;
271 this->object_infos.resize(0);
272 this->binary_info = nullptr;
273 this->libsimgrid_info = nullptr;
275 std::vector<simgrid::xbt::VmMap> const& maps = this->memory_map_;
277 const char* current_name = nullptr;
279 this->object_infos.clear();
281 for (size_t i = 0; i < maps.size(); i++) {
282 simgrid::xbt::VmMap const& reg = maps[i];
283 const char* pathname = maps[i].pathname.c_str();
286 if (maps[i].pathname.empty()) {
287 current_name = nullptr;
291 // [stack], [vvar], [vsyscall], [vdso] ...
292 if (pathname[0] == '[') {
293 if ((reg.prot & PROT_WRITE) && not memcmp(pathname, "[stack]", 7)) {
294 this->maestro_stack_start_ = remote(reg.start_addr);
295 this->maestro_stack_end_ = remote(reg.end_addr);
297 current_name = nullptr;
301 if (current_name && strcmp(current_name, pathname) == 0)
304 current_name = pathname;
305 if (not(reg.prot & PROT_READ) && (reg.prot & PROT_EXEC))
308 const bool is_executable = not i;
310 if (not is_executable) {
311 libname = get_lib_name(pathname);
312 if (is_filtered_lib(libname)) {
317 std::shared_ptr<simgrid::mc::ObjectInformation> info =
318 simgrid::mc::createObjectInformation(this->memory_map_, pathname);
319 this->object_infos.push_back(info);
321 this->binary_info = info;
322 else if (is_simgrid_lib(libname))
323 this->libsimgrid_info = info;
326 // Resolve time (including across different objects):
327 for (auto const& object_info : this->object_infos)
328 postProcessObjectInformation(this, object_info.get());
330 xbt_assert(this->maestro_stack_start_, "Did not find maestro_stack_start");
331 xbt_assert(this->maestro_stack_end_, "Did not find maestro_stack_end");
333 XBT_DEBUG("Get debug information done !");
336 std::shared_ptr<simgrid::mc::ObjectInformation> RemoteClient::find_object_info(RemotePtr<void> addr) const
338 for (auto const& object_info : this->object_infos)
339 if (addr.address() >= (std::uint64_t)object_info->start && addr.address() <= (std::uint64_t)object_info->end)
344 std::shared_ptr<ObjectInformation> RemoteClient::find_object_info_exec(RemotePtr<void> addr) const
346 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
347 if (addr.address() >= (std::uint64_t)info->start_exec && addr.address() <= (std::uint64_t)info->end_exec)
352 std::shared_ptr<ObjectInformation> RemoteClient::find_object_info_rw(RemotePtr<void> addr) const
354 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
355 if (addr.address() >= (std::uint64_t)info->start_rw && addr.address() <= (std::uint64_t)info->end_rw)
360 simgrid::mc::Frame* RemoteClient::find_function(RemotePtr<void> ip) const
362 std::shared_ptr<simgrid::mc::ObjectInformation> info = this->find_object_info_exec(ip);
363 return info ? info->find_function((void*)ip.address()) : nullptr;
366 /** Find (one occurrence of) the named variable definition
368 simgrid::mc::Variable* RemoteClient::find_variable(const char* name) const
370 // First lookup the variable in the executable shared object.
371 // A global variable used directly by the executable code from a library
372 // is reinstanciated in the executable memory .data/.bss.
373 // We need to look up the variable in the executable first.
374 if (this->binary_info) {
375 std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->binary_info;
376 simgrid::mc::Variable* var = info->find_variable(name);
381 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos) {
382 simgrid::mc::Variable* var = info->find_variable(name);
390 void RemoteClient::read_variable(const char* name, void* target, size_t size) const
392 simgrid::mc::Variable* var = this->find_variable(name);
393 xbt_assert(var->address, "No simple location for this variable");
394 xbt_assert(var->type->full_type, "Partial type for %s, cannot check size", name);
395 xbt_assert((size_t)var->type->full_type->byte_size == size, "Unexpected size for %s (expected %zu, was %zu)", name,
396 size, (size_t)var->type->full_type->byte_size);
397 this->read_bytes(target, size, remote(var->address));
400 std::string RemoteClient::read_string(RemotePtr<char> address) const
405 std::vector<char> res(128);
409 ssize_t c = pread(this->memory_file, res.data() + off, res.size() - off, (off_t)address.address() + off);
414 xbt_die("Could not read from from remote process");
417 xbt_die("Could not read string from remote process");
419 void* p = memchr(res.data() + off, '\0', c);
421 return std::string(res.data());
424 if (off == (off_t)res.size())
425 res.resize(res.size() * 2);
429 const void* RemoteClient::read_bytes(void* buffer, std::size_t size, RemotePtr<void> address, int process_index,
430 ReadOptions /*options*/) const
433 if (process_index != simgrid::mc::ProcessIndexDisabled) {
434 std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->find_object_info_rw(address);
435 // Segment overlap is not handled.
436 if (info.get() && this->privatized(*info)) {
437 if (process_index < 0)
438 xbt_die("Missing process index");
439 if (process_index >= (int)MC_smpi_process_count())
440 xbt_die("Invalid process index");
442 // Read smpi_privatization_regions from MCed:
443 smpi_privatization_region_t remote_smpi_privatization_regions =
444 mc_model_checker->process().read_variable<smpi_privatization_region_t>("smpi_privatization_regions");
446 s_smpi_privatization_region_t privatization_region =
447 mc_model_checker->process().read<s_smpi_privatization_region_t>(
448 remote(remote_smpi_privatization_regions + process_index));
450 // Address translation in the privatization segment:
451 size_t offset = address.address() - (std::uint64_t)info->start_rw;
452 address = remote((char*)privatization_region.address + offset);
456 if (pread_whole(this->memory_file, buffer, size, (size_t)address.address()) < 0)
457 xbt_die("Read at %p from process %lli failed", (void*)address.address(), (long long)this->pid_);
461 /** Write data to a process memory
463 * @param buffer local memory address (source)
464 * @param len data size
465 * @param address target process memory address (target)
467 void RemoteClient::write_bytes(const void* buffer, size_t len, RemotePtr<void> address)
469 if (pwrite_whole(this->memory_file, buffer, len, (size_t)address.address()) < 0)
470 xbt_die("Write to process %lli failed", (long long)this->pid_);
473 void RemoteClient::clear_bytes(RemotePtr<void> address, size_t len)
475 pthread_once(&zero_buffer_flag, zero_buffer_init);
477 size_t s = len > zero_buffer_size ? zero_buffer_size : len;
478 this->write_bytes(zero_buffer, s, address);
479 address = remote((char*)address.address() + s);
484 void RemoteClient::ignore_region(std::uint64_t addr, std::size_t size)
486 IgnoredRegion region;
490 if (ignored_regions_.empty()) {
491 ignored_regions_.push_back(region);
495 unsigned int cursor = 0;
496 IgnoredRegion* current_region = nullptr;
499 int end = ignored_regions_.size() - 1;
500 while (start <= end) {
501 cursor = (start + end) / 2;
502 current_region = &ignored_regions_[cursor];
503 if (current_region->addr == addr) {
504 if (current_region->size == size)
506 else if (current_region->size < size)
510 } else if (current_region->addr < addr)
516 std::size_t position;
517 if (current_region->addr == addr) {
518 if (current_region->size < size)
519 position = cursor + 1;
522 } else if (current_region->addr < addr)
523 position = cursor + 1;
526 ignored_regions_.insert(ignored_regions_.begin() + position, region);
529 void RemoteClient::ignore_heap(IgnoredHeapRegion const& region)
531 if (ignored_heap_.empty()) {
532 ignored_heap_.push_back(std::move(region));
536 typedef std::vector<IgnoredHeapRegion>::size_type size_type;
539 size_type end = ignored_heap_.size() - 1;
541 // Binary search the position of insertion:
543 while (start <= end) {
544 cursor = start + (end - start) / 2;
545 auto& current_region = ignored_heap_[cursor];
546 if (current_region.address == region.address)
548 else if (current_region.address < region.address)
550 else if (cursor != 0)
557 // Insert it mc_heap_ignore_region_t:
558 if (ignored_heap_[cursor].address < region.address)
560 ignored_heap_.insert(ignored_heap_.begin() + cursor, region);
563 void RemoteClient::unignore_heap(void* address, size_t size)
565 typedef std::vector<IgnoredHeapRegion>::size_type size_type;
568 size_type end = ignored_heap_.size() - 1;
572 while (start <= end) {
573 cursor = (start + end) / 2;
574 auto& region = ignored_heap_[cursor];
575 if (region.address < address)
577 else if ((char*)region.address <= ((char*)address + size)) {
578 ignored_heap_.erase(ignored_heap_.begin() + cursor);
580 } else if (cursor != 0)
588 void RemoteClient::ignore_local_variable(const char* var_name, const char* frame_name)
590 if (frame_name != nullptr && strcmp(frame_name, "*") == 0)
591 frame_name = nullptr;
592 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos)
593 info->remove_local_variable(var_name, frame_name);
596 std::vector<simgrid::mc::ActorInformation>& RemoteClient::actors()
598 this->refresh_simix();
599 return smx_actors_infos;
602 std::vector<simgrid::mc::ActorInformation>& RemoteClient::dead_actors()
604 this->refresh_simix();
605 return smx_dead_actors_infos;
608 void RemoteClient::dumpStack()
610 unw_addr_space_t as = unw_create_addr_space(&_UPT_accessors, BYTE_ORDER);
612 XBT_ERROR("Could not initialize ptrace address space");
616 void* context = _UPT_create(this->pid_);
617 if (context == nullptr) {
618 unw_destroy_addr_space(as);
619 XBT_ERROR("Could not initialize ptrace context");
624 if (unw_init_remote(&cursor, as, context) != 0) {
625 _UPT_destroy(context);
626 unw_destroy_addr_space(as);
627 XBT_ERROR("Could not initialiez ptrace cursor");
631 simgrid::mc::dumpStack(stderr, cursor);
633 _UPT_destroy(context);
634 unw_destroy_addr_space(as);
637 bool RemoteClient::actor_is_enabled(aid_t pid)
639 s_mc_message_actor_enabled_t msg{MC_MESSAGE_ACTOR_ENABLED, pid};
640 process()->getChannel().send(msg);
641 char buff[MC_MESSAGE_LENGTH];
642 ssize_t received = process()->getChannel().receive(buff, MC_MESSAGE_LENGTH, true);
643 xbt_assert(received == sizeof(s_mc_message_int_t), "Unexpected size in answer to ACTOR_ENABLED");
644 return ((s_mc_message_int_t*)buff)->value;