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 */
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_snapshot.hpp"
39 #include "src/mc/mc_unw.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 "libasan", /* gcc sanitizers */
68 "libargp", /* workarounds for glibc-less systems */
74 "libboost_context-mt",
101 static bool is_simgrid_lib(const std::string& libname)
103 return libname == "libsimgrid";
106 static bool is_filtered_lib(const std::string& libname)
108 return std::find(begin(filtered_libraries), end(filtered_libraries), libname) != end(filtered_libraries);
111 static std::string get_lib_name(const std::string& pathname)
113 constexpr char digits[] = ".0123456789";
114 std::string map_basename = simgrid::xbt::Path(pathname).getBasename();
117 size_t pos = map_basename.rfind(".so");
118 if (pos != std::string::npos && map_basename.find_first_not_of(digits, pos + 3) == std::string::npos) {
119 // strip the extension (matching regex "\.so[.0-9]*$")
120 libname.assign(map_basename, 0, pos);
122 // strip the version suffix (matching regex "-[.0-9-]*$")
124 pos = libname.rfind('-');
125 if (pos == std::string::npos || libname.find_first_not_of(digits, pos + 1) != std::string::npos)
134 static ssize_t pread_whole(int fd, void* buf, size_t count, off_t offset)
136 char* buffer = (char*)buf;
137 ssize_t real_count = count;
139 ssize_t res = pread(fd, buffer, count, offset);
146 else if (errno != EINTR) {
147 perror("pread_whole");
154 static ssize_t pwrite_whole(int fd, const void* buf, size_t count, off_t offset)
156 const char* buffer = (const char*)buf;
157 ssize_t real_count = count;
159 ssize_t res = pwrite(fd, buffer, count, offset);
166 else if (errno != EINTR)
172 static pthread_once_t zero_buffer_flag = PTHREAD_ONCE_INIT;
173 static const void* zero_buffer;
174 static const size_t zero_buffer_size = 10 * 4096;
176 static void zero_buffer_init()
178 int fd = open("/dev/zero", O_RDONLY);
180 xbt_die("Could not open /dev/zero");
181 zero_buffer = mmap(nullptr, zero_buffer_size, PROT_READ, MAP_SHARED, fd, 0);
182 if (zero_buffer == MAP_FAILED)
183 xbt_die("Could not map the zero buffer");
187 int open_vm(pid_t pid, int flags)
189 const size_t buffer_size = 30;
190 char buffer[buffer_size];
191 int res = snprintf(buffer, buffer_size, "/proc/%lli/mem", (long long)pid);
192 if (res < 0 || (size_t)res >= buffer_size) {
193 errno = ENAMETOOLONG;
196 return open(buffer, flags);
201 RemoteClient::RemoteClient(pid_t pid, int sockfd) : AddressSpace(this), pid_(pid), channel_(sockfd), running_(true)
205 void RemoteClient::init()
207 this->memory_map_ = simgrid::xbt::get_memory_map(this->pid_);
208 this->init_memory_map_info();
210 int fd = open_vm(this->pid_, O_RDWR);
212 xbt_die("Could not open file for process virtual address space");
213 this->memory_file = fd;
215 // Read std_heap (is a struct mdesc*):
216 simgrid::mc::Variable* std_heap_var = this->find_variable("__mmalloc_default_mdp");
217 if (not std_heap_var)
218 xbt_die("No heap information in the target process");
219 if (not std_heap_var->address)
220 xbt_die("No constant address for this variable");
221 this->read_bytes(&this->heap_address, sizeof(mdesc*), remote(std_heap_var->address),
222 simgrid::mc::ProcessIndexDisabled);
224 this->smx_actors_infos.clear();
225 this->smx_dead_actors_infos.clear();
226 this->unw_addr_space = simgrid::mc::UnwindContext::createUnwindAddressSpace();
227 this->unw_underlying_addr_space = simgrid::unw::create_addr_space();
228 this->unw_underlying_context = simgrid::unw::create_context(this->unw_underlying_addr_space, this->pid_);
231 RemoteClient::~RemoteClient()
233 if (this->memory_file >= 0)
234 close(this->memory_file);
236 if (this->unw_underlying_addr_space != unw_local_addr_space) {
237 if (this->unw_underlying_addr_space)
238 unw_destroy_addr_space(this->unw_underlying_addr_space);
239 if (this->unw_underlying_context)
240 _UPT_destroy(this->unw_underlying_context);
243 unw_destroy_addr_space(this->unw_addr_space);
246 /** Refresh the information about the process
248 * Do not use directly, this is used by the getters when appropriate
249 * in order to have fresh data.
251 void RemoteClient::refresh_heap()
253 // Read/dereference/refresh the std_heap pointer:
255 this->heap = std::unique_ptr<s_xbt_mheap_t>(new s_xbt_mheap_t());
256 this->read_bytes(this->heap.get(), sizeof(mdesc), remote(this->heap_address), simgrid::mc::ProcessIndexDisabled);
257 this->cache_flags_ |= RemoteClient::cache_heap;
260 /** Refresh the information about the process
262 * Do not use direclty, this is used by the getters when appropriate
263 * in order to have fresh data.
265 void RemoteClient::refresh_malloc_info()
267 // Refresh process->heapinfo:
268 if (this->cache_flags_ & RemoteClient::cache_malloc)
270 size_t count = this->heap->heaplimit + 1;
271 if (this->heap_info.size() < count)
272 this->heap_info.resize(count);
273 this->read_bytes(this->heap_info.data(), count * sizeof(malloc_info), remote(this->heap->heapinfo),
274 simgrid::mc::ProcessIndexDisabled);
275 this->cache_flags_ |= RemoteClient::cache_malloc;
278 /** @brief Finds the range of the different memory segments and binary paths */
279 void RemoteClient::init_memory_map_info()
281 XBT_DEBUG("Get debug information ...");
282 this->maestro_stack_start_ = nullptr;
283 this->maestro_stack_end_ = nullptr;
284 this->object_infos.resize(0);
285 this->binary_info = nullptr;
286 this->libsimgrid_info = nullptr;
288 std::vector<simgrid::xbt::VmMap> const& maps = this->memory_map_;
290 const char* current_name = nullptr;
292 this->object_infos.clear();
294 for (size_t i = 0; i < maps.size(); i++) {
295 simgrid::xbt::VmMap const& reg = maps[i];
296 const char* pathname = maps[i].pathname.c_str();
299 if (maps[i].pathname.empty()) {
300 current_name = nullptr;
304 // [stack], [vvar], [vsyscall], [vdso] ...
305 if (pathname[0] == '[') {
306 if ((reg.prot & PROT_WRITE) && not memcmp(pathname, "[stack]", 7)) {
307 this->maestro_stack_start_ = remote(reg.start_addr);
308 this->maestro_stack_end_ = remote(reg.end_addr);
310 current_name = nullptr;
314 if (current_name && strcmp(current_name, pathname) == 0)
317 current_name = pathname;
318 if (not(reg.prot & PROT_READ) && (reg.prot & PROT_EXEC))
321 const bool is_executable = not i;
323 if (not is_executable) {
324 libname = get_lib_name(pathname);
325 if (is_filtered_lib(libname)) {
330 std::shared_ptr<simgrid::mc::ObjectInformation> info =
331 simgrid::mc::createObjectInformation(this->memory_map_, pathname);
332 this->object_infos.push_back(info);
334 this->binary_info = info;
335 else if (is_simgrid_lib(libname))
336 this->libsimgrid_info = info;
339 // Resolve time (including across different objects):
340 for (auto const& object_info : this->object_infos)
341 postProcessObjectInformation(this, object_info.get());
343 xbt_assert(this->maestro_stack_start_, "Did not find maestro_stack_start");
344 xbt_assert(this->maestro_stack_end_, "Did not find maestro_stack_end");
346 XBT_DEBUG("Get debug information done !");
349 std::shared_ptr<simgrid::mc::ObjectInformation> RemoteClient::find_object_info(RemotePtr<void> addr) const
351 for (auto const& object_info : this->object_infos)
352 if (addr.address() >= (std::uint64_t)object_info->start && addr.address() <= (std::uint64_t)object_info->end)
357 std::shared_ptr<ObjectInformation> RemoteClient::find_object_info_exec(RemotePtr<void> addr) const
359 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
360 if (addr.address() >= (std::uint64_t)info->start_exec && addr.address() <= (std::uint64_t)info->end_exec)
365 std::shared_ptr<ObjectInformation> RemoteClient::find_object_info_rw(RemotePtr<void> addr) const
367 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
368 if (addr.address() >= (std::uint64_t)info->start_rw && addr.address() <= (std::uint64_t)info->end_rw)
373 simgrid::mc::Frame* RemoteClient::find_function(RemotePtr<void> ip) const
375 std::shared_ptr<simgrid::mc::ObjectInformation> info = this->find_object_info_exec(ip);
376 return info ? info->find_function((void*)ip.address()) : nullptr;
379 /** Find (one occurrence of) the named variable definition
381 simgrid::mc::Variable* RemoteClient::find_variable(const char* name) const
383 // First lookup the variable in the executable shared object.
384 // A global variable used directly by the executable code from a library
385 // is reinstanciated in the executable memory .data/.bss.
386 // We need to look up the variable in the executable first.
387 if (this->binary_info) {
388 std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->binary_info;
389 simgrid::mc::Variable* var = info->find_variable(name);
394 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos) {
395 simgrid::mc::Variable* var = info->find_variable(name);
403 void RemoteClient::read_variable(const char* name, void* target, size_t size) const
405 simgrid::mc::Variable* var = this->find_variable(name);
406 xbt_assert(var->address, "No simple location for this variable");
407 xbt_assert(var->type->full_type, "Partial type for %s, cannot check size", name);
408 xbt_assert((size_t)var->type->full_type->byte_size == size, "Unexpected size for %s (expected %zu, was %zu)", name,
409 size, (size_t)var->type->full_type->byte_size);
410 this->read_bytes(target, size, remote(var->address));
413 std::string RemoteClient::read_string(RemotePtr<char> address) const
418 // TODO, use std::vector with .data() in C++17 to avoid useless copies
419 std::vector<char> res(128);
423 ssize_t c = pread(this->memory_file, res.data() + off, res.size() - off, (off_t)address.address() + off);
428 xbt_die("Could not read from from remote process");
431 xbt_die("Could not read string from remote process");
433 void* p = memchr(res.data() + off, '\0', c);
435 return std::string(res.data());
438 if (off == (off_t)res.size())
439 res.resize(res.size() * 2);
443 const void* RemoteClient::read_bytes(void* buffer, std::size_t size, RemotePtr<void> address, int process_index,
444 ReadOptions options) const
446 if (process_index != simgrid::mc::ProcessIndexDisabled) {
447 std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->find_object_info_rw((void*)address.address());
448 // Segment overlap is not handled.
450 if (info.get() && this->privatized(*info)) {
451 if (process_index < 0)
452 xbt_die("Missing process index");
453 if (process_index >= (int)MC_smpi_process_count())
454 xbt_die("Invalid process index");
456 // Read smpi_privatization_regions from MCed:
457 smpi_privatization_region_t remote_smpi_privatization_regions =
458 mc_model_checker->process().read_variable<smpi_privatization_region_t>("smpi_privatization_regions");
460 s_smpi_privatization_region_t privatization_region =
461 mc_model_checker->process().read<s_smpi_privatization_region_t>(
462 remote(remote_smpi_privatization_regions + process_index));
464 // Address translation in the privatization segment:
465 size_t offset = address.address() - (std::uint64_t)info->start_rw;
466 address = remote((char*)privatization_region.address + offset);
470 if (pread_whole(this->memory_file, buffer, size, (size_t)address.address()) < 0)
471 xbt_die("Read at %p from process %lli failed", (void*)address.address(), (long long)this->pid_);
475 /** Write data to a process memory
477 * @param buffer local memory address (source)
478 * @param len data size
479 * @param address target process memory address (target)
481 void RemoteClient::write_bytes(const void* buffer, size_t len, RemotePtr<void> address)
483 if (pwrite_whole(this->memory_file, buffer, len, (size_t)address.address()) < 0)
484 xbt_die("Write to process %lli failed", (long long)this->pid_);
487 void RemoteClient::clear_bytes(RemotePtr<void> address, size_t len)
489 pthread_once(&zero_buffer_flag, zero_buffer_init);
491 size_t s = len > zero_buffer_size ? zero_buffer_size : len;
492 this->write_bytes(zero_buffer, s, address);
493 address = remote((char*)address.address() + s);
498 void RemoteClient::ignore_region(std::uint64_t addr, std::size_t size)
500 IgnoredRegion region;
504 if (ignored_regions_.empty()) {
505 ignored_regions_.push_back(region);
509 unsigned int cursor = 0;
510 IgnoredRegion* current_region = nullptr;
513 int end = ignored_regions_.size() - 1;
514 while (start <= end) {
515 cursor = (start + end) / 2;
516 current_region = &ignored_regions_[cursor];
517 if (current_region->addr == addr) {
518 if (current_region->size == size)
520 else if (current_region->size < size)
524 } else if (current_region->addr < addr)
530 std::size_t position;
531 if (current_region->addr == addr) {
532 if (current_region->size < size)
533 position = cursor + 1;
536 } else if (current_region->addr < addr)
537 position = cursor + 1;
540 ignored_regions_.insert(ignored_regions_.begin() + position, region);
543 void RemoteClient::ignore_heap(IgnoredHeapRegion const& region)
545 if (ignored_heap_.empty()) {
546 ignored_heap_.push_back(std::move(region));
550 typedef std::vector<IgnoredHeapRegion>::size_type size_type;
553 size_type end = ignored_heap_.size() - 1;
555 // Binary search the position of insertion:
557 while (start <= end) {
558 cursor = start + (end - start) / 2;
559 auto& current_region = ignored_heap_[cursor];
560 if (current_region.address == region.address)
562 else if (current_region.address < region.address)
564 else if (cursor != 0)
571 // Insert it mc_heap_ignore_region_t:
572 if (ignored_heap_[cursor].address < region.address)
574 ignored_heap_.insert(ignored_heap_.begin() + cursor, region);
577 void RemoteClient::unignore_heap(void* address, size_t size)
579 typedef std::vector<IgnoredHeapRegion>::size_type size_type;
582 size_type end = ignored_heap_.size() - 1;
586 while (start <= end) {
587 cursor = (start + end) / 2;
588 auto& region = ignored_heap_[cursor];
589 if (region.address == address) {
590 ignored_heap_.erase(ignored_heap_.begin() + cursor);
592 } else if (region.address < address)
594 else if ((char*)region.address <= ((char*)address + size)) {
595 ignored_heap_.erase(ignored_heap_.begin() + cursor);
597 } else if (cursor != 0)
605 void RemoteClient::ignore_local_variable(const char* var_name, const char* frame_name)
607 if (frame_name != nullptr && strcmp(frame_name, "*") == 0)
608 frame_name = nullptr;
609 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos)
610 info->remove_local_variable(var_name, frame_name);
613 std::vector<simgrid::mc::ActorInformation>& RemoteClient::actors()
615 this->refresh_simix();
616 return smx_actors_infos;
619 std::vector<simgrid::mc::ActorInformation>& RemoteClient::dead_actors()
621 this->refresh_simix();
622 return smx_dead_actors_infos;
625 void RemoteClient::dumpStack()
627 unw_addr_space_t as = unw_create_addr_space(&_UPT_accessors, BYTE_ORDER);
629 XBT_ERROR("Could not initialize ptrace address space");
633 void* context = _UPT_create(this->pid_);
634 if (context == nullptr) {
635 unw_destroy_addr_space(as);
636 XBT_ERROR("Could not initialize ptrace context");
641 if (unw_init_remote(&cursor, as, context) != 0) {
642 _UPT_destroy(context);
643 unw_destroy_addr_space(as);
644 XBT_ERROR("Could not initialiez ptrace cursor");
648 simgrid::mc::dumpStack(stderr, cursor);
650 _UPT_destroy(context);
651 unw_destroy_addr_space(as);
655 bool RemoteClient::actor_is_enabled(aid_t pid)
657 s_mc_message_actor_enabled msg{MC_MESSAGE_ACTOR_ENABLED, pid};
658 process()->getChannel().send(msg);
659 char buff[MC_MESSAGE_LENGTH];
660 ssize_t received = process()->getChannel().receive(buff, MC_MESSAGE_LENGTH, true);
661 xbt_assert(received == sizeof(s_mc_message_int), "Unexpected size in answer to ACTOR_ENABLED");
662 return ((mc_message_int_t*)buff)->value;