1 /* Copyright (c) 2014-2017. 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 */
13 #include <sys/ptrace.h>
19 #include <sys/mman.h> // PROT_*
20 #include <sys/types.h>
27 #include <libunwind-ptrace.h>
28 #include <libunwind.h>
31 #include "xbt/file.hpp"
33 #include <xbt/mmalloc.h>
35 #include "src/mc/mc_smx.hpp"
36 #include "src/mc/mc_snapshot.hpp"
37 #include "src/mc/mc_unw.hpp"
39 #include "src/mc/AddressSpace.hpp"
40 #include "src/mc/ObjectInformation.hpp"
41 #include "src/mc/Variable.hpp"
42 #include "src/mc/remote/RemoteClient.hpp"
44 using simgrid::mc::remote;
46 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_process, mc, "MC process information");
50 #define SO_RE "\\.so[\\.0-9]*$"
51 #define VERSION_RE "-[\\.0-9-]*$"
56 // List of library which memory segments are not considered:
57 static const char* const filtered_libraries[] = {
60 #elif defined __FreeBSD__
63 "libkvm", /* kernel data access library */
64 "libprocstat", /* process and file information retrieval */
65 "libthr", /* thread library */
68 "libasan", /* gcc sanitizers */
69 "libargp", /* workarounds for glibc-less systems */
75 "libboost_context-mt",
102 static bool is_simgrid_lib(const char* libname)
104 return not strcmp(libname, "libsimgrid");
107 static bool is_filtered_lib(const char* libname)
109 for (const char* const& filtered_lib : filtered_libraries)
110 if (strcmp(libname, filtered_lib) == 0)
115 struct s_mc_memory_map_re {
120 static char* get_lib_name(const char* pathname, s_mc_memory_map_re* res)
122 std::string map_basename = simgrid::xbt::Path(pathname).getBasename();
125 if (regexec(&res->so_re, map_basename.c_str(), 1, &match, 0))
128 char* libname = strndup(map_basename.c_str(), match.rm_so);
130 // Strip the version suffix:
131 if (libname && not regexec(&res->version_re, libname, 1, &match, 0)) {
132 char* temp = libname;
133 libname = strndup(temp, match.rm_so);
140 static ssize_t pread_whole(int fd, void* buf, size_t count, off_t offset)
142 char* buffer = (char*)buf;
143 ssize_t real_count = count;
145 ssize_t res = pread(fd, buffer, count, offset);
152 else if (errno != EINTR) {
153 perror("pread_whole");
160 static ssize_t pwrite_whole(int fd, const void* buf, size_t count, off_t offset)
162 const char* buffer = (const char*)buf;
163 ssize_t real_count = count;
165 ssize_t res = pwrite(fd, buffer, count, offset);
172 else if (errno != EINTR)
178 static pthread_once_t zero_buffer_flag = PTHREAD_ONCE_INIT;
179 static const void* zero_buffer;
180 static const size_t zero_buffer_size = 10 * 4096;
182 static void zero_buffer_init()
184 int fd = open("/dev/zero", O_RDONLY);
186 xbt_die("Could not open /dev/zero");
187 zero_buffer = mmap(nullptr, zero_buffer_size, PROT_READ, MAP_SHARED, fd, 0);
188 if (zero_buffer == MAP_FAILED)
189 xbt_die("Could not map the zero buffer");
193 int open_vm(pid_t pid, int flags)
195 const size_t buffer_size = 30;
196 char buffer[buffer_size];
197 int res = snprintf(buffer, buffer_size, "/proc/%lli/mem", (long long)pid);
198 if (res < 0 || (size_t)res >= buffer_size) {
199 errno = ENAMETOOLONG;
202 return open(buffer, flags);
207 RemoteClient::RemoteClient(pid_t pid, int sockfd) : AddressSpace(this), pid_(pid), channel_(sockfd), running_(true)
211 void RemoteClient::init()
213 this->memory_map_ = simgrid::xbt::get_memory_map(this->pid_);
214 this->init_memory_map_info();
216 int fd = open_vm(this->pid_, O_RDWR);
218 xbt_die("Could not open file for process virtual address space");
219 this->memory_file = fd;
221 // Read std_heap (is a struct mdesc*):
222 simgrid::mc::Variable* std_heap_var = this->find_variable("__mmalloc_default_mdp");
223 if (not std_heap_var)
224 xbt_die("No heap information in the target process");
225 if (not std_heap_var->address)
226 xbt_die("No constant address for this variable");
227 this->read_bytes(&this->heap_address, sizeof(mdesc*), remote(std_heap_var->address),
228 simgrid::mc::ProcessIndexDisabled);
230 this->smx_actors_infos.clear();
231 this->smx_dead_actors_infos.clear();
232 this->unw_addr_space = simgrid::mc::UnwindContext::createUnwindAddressSpace();
233 this->unw_underlying_addr_space = simgrid::unw::create_addr_space();
234 this->unw_underlying_context = simgrid::unw::create_context(this->unw_underlying_addr_space, this->pid_);
237 RemoteClient::~RemoteClient()
239 if (this->memory_file >= 0)
240 close(this->memory_file);
242 if (this->unw_underlying_addr_space != unw_local_addr_space) {
243 if (this->unw_underlying_addr_space)
244 unw_destroy_addr_space(this->unw_underlying_addr_space);
245 if (this->unw_underlying_context)
246 _UPT_destroy(this->unw_underlying_context);
249 unw_destroy_addr_space(this->unw_addr_space);
252 /** Refresh the information about the process
254 * Do not use directly, this is used by the getters when appropriate
255 * in order to have fresh data.
257 void RemoteClient::refresh_heap()
259 // Read/dereference/refresh the std_heap pointer:
261 this->heap = std::unique_ptr<s_xbt_mheap_t>(new s_xbt_mheap_t());
262 this->read_bytes(this->heap.get(), sizeof(mdesc), remote(this->heap_address), simgrid::mc::ProcessIndexDisabled);
263 this->cache_flags_ |= RemoteClient::cache_heap;
266 /** Refresh the information about the process
268 * Do not use direclty, this is used by the getters when appropriate
269 * in order to have fresh data.
271 void RemoteClient::refresh_malloc_info()
273 // Refresh process->heapinfo:
274 if (this->cache_flags_ & RemoteClient::cache_malloc)
276 size_t count = this->heap->heaplimit + 1;
277 if (this->heap_info.size() < count)
278 this->heap_info.resize(count);
279 this->read_bytes(this->heap_info.data(), count * sizeof(malloc_info), remote(this->heap->heapinfo),
280 simgrid::mc::ProcessIndexDisabled);
281 this->cache_flags_ |= RemoteClient::cache_malloc;
284 /** @brief Finds the range of the different memory segments and binary paths */
285 void RemoteClient::init_memory_map_info()
287 XBT_DEBUG("Get debug information ...");
288 this->maestro_stack_start_ = nullptr;
289 this->maestro_stack_end_ = nullptr;
290 this->object_infos.resize(0);
291 this->binary_info = nullptr;
292 this->libsimgrid_info = nullptr;
294 s_mc_memory_map_re res;
296 if (regcomp(&res.so_re, SO_RE, 0) || regcomp(&res.version_re, VERSION_RE, 0))
297 xbt_die(".so regexp did not compile");
299 std::vector<simgrid::xbt::VmMap> const& maps = this->memory_map_;
301 const char* current_name = nullptr;
303 this->object_infos.clear();
305 for (size_t i = 0; i < maps.size(); i++) {
306 simgrid::xbt::VmMap const& reg = maps[i];
307 const char* pathname = maps[i].pathname.c_str();
310 if (maps[i].pathname.empty()) {
311 current_name = nullptr;
315 // [stack], [vvar], [vsyscall], [vdso] ...
316 if (pathname[0] == '[') {
317 if ((reg.prot & PROT_WRITE) && not memcmp(pathname, "[stack]", 7)) {
318 this->maestro_stack_start_ = remote(reg.start_addr);
319 this->maestro_stack_end_ = remote(reg.end_addr);
321 current_name = nullptr;
325 if (current_name && strcmp(current_name, pathname) == 0)
328 current_name = pathname;
329 if (not(reg.prot & PROT_READ) && (reg.prot & PROT_EXEC))
332 const bool is_executable = not i;
333 char* libname = nullptr;
334 if (not is_executable) {
335 libname = get_lib_name(pathname, &res);
338 if (is_filtered_lib(libname)) {
344 std::shared_ptr<simgrid::mc::ObjectInformation> info =
345 simgrid::mc::createObjectInformation(this->memory_map_, pathname);
346 this->object_infos.push_back(info);
348 this->binary_info = info;
349 else if (libname && is_simgrid_lib(libname))
350 this->libsimgrid_info = info;
355 regfree(&res.version_re);
357 // Resolve time (including across different objects):
358 for (auto const& object_info : this->object_infos)
359 postProcessObjectInformation(this, object_info.get());
361 xbt_assert(this->maestro_stack_start_, "Did not find maestro_stack_start");
362 xbt_assert(this->maestro_stack_end_, "Did not find maestro_stack_end");
364 XBT_DEBUG("Get debug information done !");
367 std::shared_ptr<simgrid::mc::ObjectInformation> RemoteClient::find_object_info(RemotePtr<void> addr) const
369 for (auto const& object_info : this->object_infos)
370 if (addr.address() >= (std::uint64_t)object_info->start && addr.address() <= (std::uint64_t)object_info->end)
375 std::shared_ptr<ObjectInformation> RemoteClient::find_object_info_exec(RemotePtr<void> addr) const
377 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
378 if (addr.address() >= (std::uint64_t)info->start_exec && addr.address() <= (std::uint64_t)info->end_exec)
383 std::shared_ptr<ObjectInformation> RemoteClient::find_object_info_rw(RemotePtr<void> addr) const
385 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
386 if (addr.address() >= (std::uint64_t)info->start_rw && addr.address() <= (std::uint64_t)info->end_rw)
391 simgrid::mc::Frame* RemoteClient::find_function(RemotePtr<void> ip) const
393 std::shared_ptr<simgrid::mc::ObjectInformation> info = this->find_object_info_exec(ip);
394 return info ? info->find_function((void*)ip.address()) : nullptr;
397 /** Find (one occurrence of) the named variable definition
399 simgrid::mc::Variable* RemoteClient::find_variable(const char* name) const
401 // First lookup the variable in the executable shared object.
402 // A global variable used directly by the executable code from a library
403 // is reinstanciated in the executable memory .data/.bss.
404 // We need to look up the variable in the executable first.
405 if (this->binary_info) {
406 std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->binary_info;
407 simgrid::mc::Variable* var = info->find_variable(name);
412 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos) {
413 simgrid::mc::Variable* var = info->find_variable(name);
421 void RemoteClient::read_variable(const char* name, void* target, size_t size) const
423 simgrid::mc::Variable* var = this->find_variable(name);
424 xbt_assert(var->address, "No simple location for this variable");
425 xbt_assert(var->type->full_type, "Partial type for %s, cannot check size", name);
426 xbt_assert((size_t)var->type->full_type->byte_size == size, "Unexpected size for %s (expected %zu, was %zu)", name,
427 size, (size_t)var->type->full_type->byte_size);
428 this->read_bytes(target, size, remote(var->address));
431 std::string RemoteClient::read_string(RemotePtr<char> address) const
436 // TODO, use std::vector with .data() in C++17 to avoid useless copies
437 std::vector<char> res(128);
441 ssize_t c = pread(this->memory_file, res.data() + off, res.size() - off, (off_t)address.address() + off);
446 xbt_die("Could not read from from remote process");
449 xbt_die("Could not read string from remote process");
451 void* p = memchr(res.data() + off, '\0', c);
453 return std::string(res.data());
456 if (off == (off_t)res.size())
457 res.resize(res.size() * 2);
461 const void* RemoteClient::read_bytes(void* buffer, std::size_t size, RemotePtr<void> address, int process_index,
462 ReadOptions options) const
464 if (process_index != simgrid::mc::ProcessIndexDisabled) {
465 std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->find_object_info_rw((void*)address.address());
466 // Segment overlap is not handled.
468 if (info.get() && this->privatized(*info)) {
469 if (process_index < 0)
470 xbt_die("Missing process index");
471 if (process_index >= (int)MC_smpi_process_count())
472 xbt_die("Invalid process index");
474 // Read smpi_privatization_regions from MCed:
475 smpi_privatization_region_t remote_smpi_privatization_regions =
476 mc_model_checker->process().read_variable<smpi_privatization_region_t>("smpi_privatization_regions");
478 s_smpi_privatization_region_t privatization_region =
479 mc_model_checker->process().read<s_smpi_privatization_region_t>(
480 remote(remote_smpi_privatization_regions + process_index));
482 // Address translation in the privatization segment:
483 size_t offset = address.address() - (std::uint64_t)info->start_rw;
484 address = remote((char*)privatization_region.address + offset);
488 if (pread_whole(this->memory_file, buffer, size, (size_t)address.address()) < 0)
489 xbt_die("Read at %p from process %lli failed", (void*)address.address(), (long long)this->pid_);
493 /** Write data to a process memory
495 * @param buffer local memory address (source)
496 * @param len data size
497 * @param address target process memory address (target)
499 void RemoteClient::write_bytes(const void* buffer, size_t len, RemotePtr<void> address)
501 if (pwrite_whole(this->memory_file, buffer, len, (size_t)address.address()) < 0)
502 xbt_die("Write to process %lli failed", (long long)this->pid_);
505 void RemoteClient::clear_bytes(RemotePtr<void> address, size_t len)
507 pthread_once(&zero_buffer_flag, zero_buffer_init);
509 size_t s = len > zero_buffer_size ? zero_buffer_size : len;
510 this->write_bytes(zero_buffer, s, address);
511 address = remote((char*)address.address() + s);
516 void RemoteClient::ignore_region(std::uint64_t addr, std::size_t size)
518 IgnoredRegion region;
522 if (ignored_regions_.empty()) {
523 ignored_regions_.push_back(region);
527 unsigned int cursor = 0;
528 IgnoredRegion* current_region = nullptr;
531 int end = ignored_regions_.size() - 1;
532 while (start <= end) {
533 cursor = (start + end) / 2;
534 current_region = &ignored_regions_[cursor];
535 if (current_region->addr == addr) {
536 if (current_region->size == size)
538 else if (current_region->size < size)
542 } else if (current_region->addr < addr)
548 std::size_t position;
549 if (current_region->addr == addr) {
550 if (current_region->size < size)
551 position = cursor + 1;
554 } else if (current_region->addr < addr)
555 position = cursor + 1;
558 ignored_regions_.insert(ignored_regions_.begin() + position, region);
561 void RemoteClient::ignore_heap(IgnoredHeapRegion const& region)
563 if (ignored_heap_.empty()) {
564 ignored_heap_.push_back(std::move(region));
568 typedef std::vector<IgnoredHeapRegion>::size_type size_type;
571 size_type end = ignored_heap_.size() - 1;
573 // Binary search the position of insertion:
575 while (start <= end) {
576 cursor = start + (end - start) / 2;
577 auto& current_region = ignored_heap_[cursor];
578 if (current_region.address == region.address)
580 else if (current_region.address < region.address)
582 else if (cursor != 0)
589 // Insert it mc_heap_ignore_region_t:
590 if (ignored_heap_[cursor].address < region.address)
592 ignored_heap_.insert(ignored_heap_.begin() + cursor, region);
595 void RemoteClient::unignore_heap(void* address, size_t size)
597 typedef std::vector<IgnoredHeapRegion>::size_type size_type;
600 size_type end = ignored_heap_.size() - 1;
604 while (start <= end) {
605 cursor = (start + end) / 2;
606 auto& region = ignored_heap_[cursor];
607 if (region.address == address) {
608 ignored_heap_.erase(ignored_heap_.begin() + cursor);
610 } else if (region.address < address)
612 else if ((char*)region.address <= ((char*)address + size)) {
613 ignored_heap_.erase(ignored_heap_.begin() + cursor);
615 } else if (cursor != 0)
623 void RemoteClient::ignore_local_variable(const char* var_name, const char* frame_name)
625 if (frame_name != nullptr && strcmp(frame_name, "*") == 0)
626 frame_name = nullptr;
627 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos)
628 info->remove_local_variable(var_name, frame_name);
631 std::vector<simgrid::mc::ActorInformation>& RemoteClient::actors()
633 this->refresh_simix();
634 return smx_actors_infos;
637 std::vector<simgrid::mc::ActorInformation>& RemoteClient::dead_actors()
639 this->refresh_simix();
640 return smx_dead_actors_infos;
643 void RemoteClient::dumpStack()
645 unw_addr_space_t as = unw_create_addr_space(&_UPT_accessors, BYTE_ORDER);
647 XBT_ERROR("Could not initialize ptrace address space");
651 void* context = _UPT_create(this->pid_);
652 if (context == nullptr) {
653 unw_destroy_addr_space(as);
654 XBT_ERROR("Could not initialize ptrace context");
659 if (unw_init_remote(&cursor, as, context) != 0) {
660 _UPT_destroy(context);
661 unw_destroy_addr_space(as);
662 XBT_ERROR("Could not initialiez ptrace cursor");
666 simgrid::mc::dumpStack(stderr, cursor);
668 _UPT_destroy(context);
669 unw_destroy_addr_space(as);
673 bool RemoteClient::actor_is_enabled(aid_t pid)
675 s_mc_message_actor_enabled msg{MC_MESSAGE_ACTOR_ENABLED, pid};
676 process()->getChannel().send(msg);
677 char buff[MC_MESSAGE_LENGTH];
678 ssize_t received = process()->getChannel().receive(buff, MC_MESSAGE_LENGTH, true);
679 xbt_assert(received == sizeof(s_mc_message_int), "Unexpected size in answer to ACTOR_ENABLED");
680 return ((mc_message_int_t*)buff)->value;