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 */
16 #include <sys/ptrace.h>
21 #include <sys/mman.h> // PROT_*
22 #include <sys/types.h>
29 #include <libunwind-ptrace.h>
30 #include <libunwind.h>
33 #include "xbt/file.hpp"
35 #include <xbt/mmalloc.h>
37 #include "src/mc/mc_smx.hpp"
38 #include "src/mc/mc_unw.hpp"
39 #include "src/mc/sosp/mc_snapshot.hpp"
41 #include "src/mc/AddressSpace.hpp"
42 #include "src/mc/ObjectInformation.hpp"
43 #include "src/mc/Variable.hpp"
44 #include "src/mc/remote/RemoteClient.hpp"
46 using simgrid::mc::remote;
48 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_process, mc, "MC process information");
55 // List of library which memory segments are not considered:
56 static const std::vector<std::string> filtered_libraries = {
59 #elif defined __FreeBSD__
62 "libkvm", /* kernel data access library */
63 "libprocstat", /* process and file information retrieval */
64 "libthr", /* thread library */
67 "libargp", /* workarounds for glibc-less systems */
68 "libasan", /* gcc sanitizers */
71 "libboost_context-mt",
72 "libboost_stacktrace_backtrace",
76 "libboost_unit_test_framework",
109 "libtsan", /* gcc sanitizers */
110 "libubsan", /* gcc sanitizers */
117 static bool is_simgrid_lib(const std::string& libname)
119 return libname == "libsimgrid";
122 static bool is_filtered_lib(const std::string& libname)
124 return std::find(begin(filtered_libraries), end(filtered_libraries), libname) != end(filtered_libraries);
127 static std::string get_lib_name(const std::string& pathname)
129 std::string map_basename = simgrid::xbt::Path(pathname).get_base_name();
132 size_t pos = map_basename.rfind(".so");
133 if (pos != std::string::npos) {
134 // strip the extension (matching regex "\.so.*$")
135 libname.assign(map_basename, 0, pos);
137 // strip the version suffix (matching regex "-[.0-9-]*$")
139 pos = libname.rfind('-');
140 if (pos == std::string::npos || libname.find_first_not_of(".0123456789", pos + 1) != std::string::npos)
149 static ssize_t pread_whole(int fd, void* buf, size_t count, off_t offset)
151 char* buffer = (char*)buf;
152 ssize_t real_count = count;
154 ssize_t res = pread(fd, buffer, count, offset);
161 else if (errno != EINTR) {
162 perror("pread_whole");
169 static ssize_t pwrite_whole(int fd, const void* buf, size_t count, off_t offset)
171 const char* buffer = (const char*)buf;
172 ssize_t real_count = count;
174 ssize_t res = pwrite(fd, buffer, count, offset);
181 else if (errno != EINTR)
187 static pthread_once_t zero_buffer_flag = PTHREAD_ONCE_INIT;
188 static const void* zero_buffer;
189 static const size_t zero_buffer_size = 10 * 4096;
191 static void zero_buffer_init()
193 int fd = open("/dev/zero", O_RDONLY);
195 xbt_die("Could not open /dev/zero");
196 zero_buffer = mmap(nullptr, zero_buffer_size, PROT_READ, MAP_SHARED, fd, 0);
197 if (zero_buffer == MAP_FAILED)
198 xbt_die("Could not map the zero buffer");
202 int open_vm(pid_t pid, int flags)
204 const size_t buffer_size = 30;
205 char buffer[buffer_size];
206 int res = snprintf(buffer, buffer_size, "/proc/%lli/mem", (long long)pid);
207 if (res < 0 || (size_t)res >= buffer_size) {
208 errno = ENAMETOOLONG;
211 return open(buffer, flags);
216 RemoteClient::RemoteClient(pid_t pid, int sockfd) : AddressSpace(this), pid_(pid), channel_(sockfd), running_(true)
220 void RemoteClient::init()
222 this->memory_map_ = simgrid::xbt::get_memory_map(this->pid_);
223 this->init_memory_map_info();
225 int fd = open_vm(this->pid_, O_RDWR);
227 xbt_die("Could not open file for process virtual address space");
228 this->memory_file = fd;
230 // Read std_heap (is a struct mdesc*):
231 simgrid::mc::Variable* std_heap_var = this->find_variable("__mmalloc_default_mdp");
232 if (not std_heap_var)
233 xbt_die("No heap information in the target process");
234 if (not std_heap_var->address)
235 xbt_die("No constant address for this variable");
236 this->read_bytes(&this->heap_address, sizeof(mdesc*), remote(std_heap_var->address),
237 simgrid::mc::ProcessIndexDisabled);
239 this->smx_actors_infos.clear();
240 this->smx_dead_actors_infos.clear();
241 this->unw_addr_space = simgrid::mc::UnwindContext::createUnwindAddressSpace();
242 this->unw_underlying_addr_space = simgrid::unw::create_addr_space();
243 this->unw_underlying_context = simgrid::unw::create_context(this->unw_underlying_addr_space, this->pid_);
246 RemoteClient::~RemoteClient()
248 if (this->memory_file >= 0)
249 close(this->memory_file);
251 if (this->unw_underlying_addr_space != unw_local_addr_space) {
252 if (this->unw_underlying_addr_space)
253 unw_destroy_addr_space(this->unw_underlying_addr_space);
254 if (this->unw_underlying_context)
255 _UPT_destroy(this->unw_underlying_context);
258 unw_destroy_addr_space(this->unw_addr_space);
261 /** Refresh the information about the process
263 * Do not use directly, this is used by the getters when appropriate
264 * in order to have fresh data.
266 void RemoteClient::refresh_heap()
268 // Read/dereference/refresh the std_heap pointer:
270 this->heap = std::unique_ptr<s_xbt_mheap_t>(new s_xbt_mheap_t());
271 this->read_bytes(this->heap.get(), sizeof(mdesc), remote(this->heap_address), simgrid::mc::ProcessIndexDisabled);
272 this->cache_flags_ |= RemoteClient::cache_heap;
275 /** Refresh the information about the process
277 * Do not use direclty, this is used by the getters when appropriate
278 * in order to have fresh data.
280 void RemoteClient::refresh_malloc_info()
282 // Refresh process->heapinfo:
283 if (this->cache_flags_ & RemoteClient::cache_malloc)
285 size_t count = this->heap->heaplimit + 1;
286 if (this->heap_info.size() < count)
287 this->heap_info.resize(count);
288 this->read_bytes(this->heap_info.data(), count * sizeof(malloc_info), remote(this->heap->heapinfo),
289 simgrid::mc::ProcessIndexDisabled);
290 this->cache_flags_ |= RemoteClient::cache_malloc;
293 /** @brief Finds the range of the different memory segments and binary paths */
294 void RemoteClient::init_memory_map_info()
296 XBT_DEBUG("Get debug information ...");
297 this->maestro_stack_start_ = nullptr;
298 this->maestro_stack_end_ = nullptr;
299 this->object_infos.resize(0);
300 this->binary_info = nullptr;
301 this->libsimgrid_info = nullptr;
303 std::vector<simgrid::xbt::VmMap> const& maps = this->memory_map_;
305 const char* current_name = nullptr;
307 this->object_infos.clear();
309 for (size_t i = 0; i < maps.size(); i++) {
310 simgrid::xbt::VmMap const& reg = maps[i];
311 const char* pathname = maps[i].pathname.c_str();
314 if (maps[i].pathname.empty()) {
315 current_name = nullptr;
319 // [stack], [vvar], [vsyscall], [vdso] ...
320 if (pathname[0] == '[') {
321 if ((reg.prot & PROT_WRITE) && not memcmp(pathname, "[stack]", 7)) {
322 this->maestro_stack_start_ = remote(reg.start_addr);
323 this->maestro_stack_end_ = remote(reg.end_addr);
325 current_name = nullptr;
329 if (current_name && strcmp(current_name, pathname) == 0)
332 current_name = pathname;
333 if (not(reg.prot & PROT_READ) && (reg.prot & PROT_EXEC))
336 const bool is_executable = not i;
338 if (not is_executable) {
339 libname = get_lib_name(pathname);
340 if (is_filtered_lib(libname)) {
345 std::shared_ptr<simgrid::mc::ObjectInformation> info =
346 simgrid::mc::createObjectInformation(this->memory_map_, pathname);
347 this->object_infos.push_back(info);
349 this->binary_info = info;
350 else if (is_simgrid_lib(libname))
351 this->libsimgrid_info = info;
354 // Resolve time (including across different objects):
355 for (auto const& object_info : this->object_infos)
356 postProcessObjectInformation(this, object_info.get());
358 xbt_assert(this->maestro_stack_start_, "Did not find maestro_stack_start");
359 xbt_assert(this->maestro_stack_end_, "Did not find maestro_stack_end");
361 XBT_DEBUG("Get debug information done !");
364 std::shared_ptr<simgrid::mc::ObjectInformation> RemoteClient::find_object_info(RemotePtr<void> addr) const
366 for (auto const& object_info : this->object_infos)
367 if (addr.address() >= (std::uint64_t)object_info->start && addr.address() <= (std::uint64_t)object_info->end)
372 std::shared_ptr<ObjectInformation> RemoteClient::find_object_info_exec(RemotePtr<void> addr) const
374 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
375 if (addr.address() >= (std::uint64_t)info->start_exec && addr.address() <= (std::uint64_t)info->end_exec)
380 std::shared_ptr<ObjectInformation> RemoteClient::find_object_info_rw(RemotePtr<void> addr) const
382 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
383 if (addr.address() >= (std::uint64_t)info->start_rw && addr.address() <= (std::uint64_t)info->end_rw)
388 simgrid::mc::Frame* RemoteClient::find_function(RemotePtr<void> ip) const
390 std::shared_ptr<simgrid::mc::ObjectInformation> info = this->find_object_info_exec(ip);
391 return info ? info->find_function((void*)ip.address()) : nullptr;
394 /** Find (one occurrence of) the named variable definition
396 simgrid::mc::Variable* RemoteClient::find_variable(const char* name) const
398 // First lookup the variable in the executable shared object.
399 // A global variable used directly by the executable code from a library
400 // is reinstanciated in the executable memory .data/.bss.
401 // We need to look up the variable in the executable first.
402 if (this->binary_info) {
403 std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->binary_info;
404 simgrid::mc::Variable* var = info->find_variable(name);
409 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos) {
410 simgrid::mc::Variable* var = info->find_variable(name);
418 void RemoteClient::read_variable(const char* name, void* target, size_t size) const
420 simgrid::mc::Variable* var = this->find_variable(name);
421 xbt_assert(var->address, "No simple location for this variable");
422 xbt_assert(var->type->full_type, "Partial type for %s, cannot check size", name);
423 xbt_assert((size_t)var->type->full_type->byte_size == size, "Unexpected size for %s (expected %zu, was %zu)", name,
424 size, (size_t)var->type->full_type->byte_size);
425 this->read_bytes(target, size, remote(var->address));
428 std::string RemoteClient::read_string(RemotePtr<char> address) const
433 std::vector<char> res(128);
437 ssize_t c = pread(this->memory_file, res.data() + off, res.size() - off, (off_t)address.address() + off);
442 xbt_die("Could not read from from remote process");
445 xbt_die("Could not read string from remote process");
447 void* p = memchr(res.data() + off, '\0', c);
449 return std::string(res.data());
452 if (off == (off_t)res.size())
453 res.resize(res.size() * 2);
457 const void* RemoteClient::read_bytes(void* buffer, std::size_t size, RemotePtr<void> address, int process_index,
458 ReadOptions /*options*/) const
461 if (process_index != simgrid::mc::ProcessIndexDisabled) {
462 std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->find_object_info_rw(address);
463 // Segment overlap is not handled.
464 if (info.get() && this->privatized(*info)) {
465 if (process_index < 0)
466 xbt_die("Missing process index");
467 if (process_index >= (int)MC_smpi_process_count())
468 xbt_die("Invalid process index");
470 // Read smpi_privatization_regions from MCed:
471 smpi_privatization_region_t remote_smpi_privatization_regions =
472 mc_model_checker->process().read_variable<smpi_privatization_region_t>("smpi_privatization_regions");
474 s_smpi_privatization_region_t privatization_region =
475 mc_model_checker->process().read<s_smpi_privatization_region_t>(
476 remote(remote_smpi_privatization_regions + process_index));
478 // Address translation in the privatization segment:
479 size_t offset = address.address() - (std::uint64_t)info->start_rw;
480 address = remote((char*)privatization_region.address + offset);
484 if (pread_whole(this->memory_file, buffer, size, (size_t)address.address()) < 0)
485 xbt_die("Read at %p from process %lli failed", (void*)address.address(), (long long)this->pid_);
489 /** Write data to a process memory
491 * @param buffer local memory address (source)
492 * @param len data size
493 * @param address target process memory address (target)
495 void RemoteClient::write_bytes(const void* buffer, size_t len, RemotePtr<void> address)
497 if (pwrite_whole(this->memory_file, buffer, len, (size_t)address.address()) < 0)
498 xbt_die("Write to process %lli failed", (long long)this->pid_);
501 void RemoteClient::clear_bytes(RemotePtr<void> address, size_t len)
503 pthread_once(&zero_buffer_flag, zero_buffer_init);
505 size_t s = len > zero_buffer_size ? zero_buffer_size : len;
506 this->write_bytes(zero_buffer, s, address);
507 address = remote((char*)address.address() + s);
512 void RemoteClient::ignore_region(std::uint64_t addr, std::size_t size)
514 IgnoredRegion region;
518 if (ignored_regions_.empty()) {
519 ignored_regions_.push_back(region);
523 unsigned int cursor = 0;
524 IgnoredRegion* current_region = nullptr;
527 int end = ignored_regions_.size() - 1;
528 while (start <= end) {
529 cursor = (start + end) / 2;
530 current_region = &ignored_regions_[cursor];
531 if (current_region->addr == addr) {
532 if (current_region->size == size)
534 else if (current_region->size < size)
538 } else if (current_region->addr < addr)
544 std::size_t position;
545 if (current_region->addr == addr) {
546 if (current_region->size < size)
547 position = cursor + 1;
550 } else if (current_region->addr < addr)
551 position = cursor + 1;
554 ignored_regions_.insert(ignored_regions_.begin() + position, region);
557 void RemoteClient::ignore_heap(IgnoredHeapRegion const& region)
559 if (ignored_heap_.empty()) {
560 ignored_heap_.push_back(std::move(region));
564 typedef std::vector<IgnoredHeapRegion>::size_type size_type;
567 size_type end = ignored_heap_.size() - 1;
569 // Binary search the position of insertion:
571 while (start <= end) {
572 cursor = start + (end - start) / 2;
573 auto& current_region = ignored_heap_[cursor];
574 if (current_region.address == region.address)
576 else if (current_region.address < region.address)
578 else if (cursor != 0)
585 // Insert it mc_heap_ignore_region_t:
586 if (ignored_heap_[cursor].address < region.address)
588 ignored_heap_.insert(ignored_heap_.begin() + cursor, region);
591 void RemoteClient::unignore_heap(void* address, size_t size)
593 typedef std::vector<IgnoredHeapRegion>::size_type size_type;
596 size_type end = ignored_heap_.size() - 1;
600 while (start <= end) {
601 cursor = (start + end) / 2;
602 auto& region = ignored_heap_[cursor];
603 if (region.address < address)
605 else if ((char*)region.address <= ((char*)address + size)) {
606 ignored_heap_.erase(ignored_heap_.begin() + cursor);
608 } else if (cursor != 0)
616 void RemoteClient::ignore_local_variable(const char* var_name, const char* frame_name)
618 if (frame_name != nullptr && strcmp(frame_name, "*") == 0)
619 frame_name = nullptr;
620 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos)
621 info->remove_local_variable(var_name, frame_name);
624 std::vector<simgrid::mc::ActorInformation>& RemoteClient::actors()
626 this->refresh_simix();
627 return smx_actors_infos;
630 std::vector<simgrid::mc::ActorInformation>& RemoteClient::dead_actors()
632 this->refresh_simix();
633 return smx_dead_actors_infos;
636 void RemoteClient::dumpStack()
638 unw_addr_space_t as = unw_create_addr_space(&_UPT_accessors, BYTE_ORDER);
640 XBT_ERROR("Could not initialize ptrace address space");
644 void* context = _UPT_create(this->pid_);
645 if (context == nullptr) {
646 unw_destroy_addr_space(as);
647 XBT_ERROR("Could not initialize ptrace context");
652 if (unw_init_remote(&cursor, as, context) != 0) {
653 _UPT_destroy(context);
654 unw_destroy_addr_space(as);
655 XBT_ERROR("Could not initialiez ptrace cursor");
659 simgrid::mc::dumpStack(stderr, cursor);
661 _UPT_destroy(context);
662 unw_destroy_addr_space(as);
665 bool RemoteClient::actor_is_enabled(aid_t pid)
667 s_mc_message_actor_enabled_t msg{MC_MESSAGE_ACTOR_ENABLED, pid};
668 process()->getChannel().send(msg);
669 char buff[MC_MESSAGE_LENGTH];
670 ssize_t received = process()->getChannel().receive(buff, MC_MESSAGE_LENGTH, true);
671 xbt_assert(received == sizeof(s_mc_message_int_t), "Unexpected size in answer to ACTOR_ENABLED");
672 return ((s_mc_message_int_t*)buff)->value;