1 /* Copyright (c) 2014-2018. 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 "libasan", /* gcc sanitizers */
68 "libargp", /* workarounds for glibc-less systems */
74 "libboost_context-mt",
78 "libboost_unit_test_framework",
107 static bool is_simgrid_lib(const std::string& libname)
109 return libname == "libsimgrid";
112 static bool is_filtered_lib(const std::string& libname)
114 return std::find(begin(filtered_libraries), end(filtered_libraries), libname) != end(filtered_libraries);
117 static std::string get_lib_name(const std::string& pathname)
119 std::string map_basename = simgrid::xbt::Path(pathname).get_base_name();
122 size_t pos = map_basename.rfind(".so");
123 if (pos != std::string::npos) {
124 // strip the extension (matching regex "\.so.*$")
125 libname.assign(map_basename, 0, pos);
127 // strip the version suffix (matching regex "-[.0-9-]*$")
129 pos = libname.rfind('-');
130 if (pos == std::string::npos || libname.find_first_not_of(".0123456789", pos + 1) != std::string::npos)
139 static ssize_t pread_whole(int fd, void* buf, size_t count, off_t offset)
141 char* buffer = (char*)buf;
142 ssize_t real_count = count;
144 ssize_t res = pread(fd, buffer, count, offset);
151 else if (errno != EINTR) {
152 perror("pread_whole");
159 static ssize_t pwrite_whole(int fd, const void* buf, size_t count, off_t offset)
161 const char* buffer = (const char*)buf;
162 ssize_t real_count = count;
164 ssize_t res = pwrite(fd, buffer, count, offset);
171 else if (errno != EINTR)
177 static pthread_once_t zero_buffer_flag = PTHREAD_ONCE_INIT;
178 static const void* zero_buffer;
179 static const size_t zero_buffer_size = 10 * 4096;
181 static void zero_buffer_init()
183 int fd = open("/dev/zero", O_RDONLY);
185 xbt_die("Could not open /dev/zero");
186 zero_buffer = mmap(nullptr, zero_buffer_size, PROT_READ, MAP_SHARED, fd, 0);
187 if (zero_buffer == MAP_FAILED)
188 xbt_die("Could not map the zero buffer");
192 int open_vm(pid_t pid, int flags)
194 const size_t buffer_size = 30;
195 char buffer[buffer_size];
196 int res = snprintf(buffer, buffer_size, "/proc/%lli/mem", (long long)pid);
197 if (res < 0 || (size_t)res >= buffer_size) {
198 errno = ENAMETOOLONG;
201 return open(buffer, flags);
206 RemoteClient::RemoteClient(pid_t pid, int sockfd) : AddressSpace(this), pid_(pid), channel_(sockfd), running_(true)
210 void RemoteClient::init()
212 this->memory_map_ = simgrid::xbt::get_memory_map(this->pid_);
213 this->init_memory_map_info();
215 int fd = open_vm(this->pid_, O_RDWR);
217 xbt_die("Could not open file for process virtual address space");
218 this->memory_file = fd;
220 // Read std_heap (is a struct mdesc*):
221 simgrid::mc::Variable* std_heap_var = this->find_variable("__mmalloc_default_mdp");
222 if (not std_heap_var)
223 xbt_die("No heap information in the target process");
224 if (not std_heap_var->address)
225 xbt_die("No constant address for this variable");
226 this->read_bytes(&this->heap_address, sizeof(mdesc*), remote(std_heap_var->address),
227 simgrid::mc::ProcessIndexDisabled);
229 this->smx_actors_infos.clear();
230 this->smx_dead_actors_infos.clear();
231 this->unw_addr_space = simgrid::mc::UnwindContext::createUnwindAddressSpace();
232 this->unw_underlying_addr_space = simgrid::unw::create_addr_space();
233 this->unw_underlying_context = simgrid::unw::create_context(this->unw_underlying_addr_space, this->pid_);
236 RemoteClient::~RemoteClient()
238 if (this->memory_file >= 0)
239 close(this->memory_file);
241 if (this->unw_underlying_addr_space != unw_local_addr_space) {
242 if (this->unw_underlying_addr_space)
243 unw_destroy_addr_space(this->unw_underlying_addr_space);
244 if (this->unw_underlying_context)
245 _UPT_destroy(this->unw_underlying_context);
248 unw_destroy_addr_space(this->unw_addr_space);
251 /** Refresh the information about the process
253 * Do not use directly, this is used by the getters when appropriate
254 * in order to have fresh data.
256 void RemoteClient::refresh_heap()
258 // Read/dereference/refresh the std_heap pointer:
260 this->heap = std::unique_ptr<s_xbt_mheap_t>(new s_xbt_mheap_t());
261 this->read_bytes(this->heap.get(), sizeof(mdesc), remote(this->heap_address), simgrid::mc::ProcessIndexDisabled);
262 this->cache_flags_ |= RemoteClient::cache_heap;
265 /** Refresh the information about the process
267 * Do not use direclty, this is used by the getters when appropriate
268 * in order to have fresh data.
270 void RemoteClient::refresh_malloc_info()
272 // Refresh process->heapinfo:
273 if (this->cache_flags_ & RemoteClient::cache_malloc)
275 size_t count = this->heap->heaplimit + 1;
276 if (this->heap_info.size() < count)
277 this->heap_info.resize(count);
278 this->read_bytes(this->heap_info.data(), count * sizeof(malloc_info), remote(this->heap->heapinfo),
279 simgrid::mc::ProcessIndexDisabled);
280 this->cache_flags_ |= RemoteClient::cache_malloc;
283 /** @brief Finds the range of the different memory segments and binary paths */
284 void RemoteClient::init_memory_map_info()
286 XBT_DEBUG("Get debug information ...");
287 this->maestro_stack_start_ = nullptr;
288 this->maestro_stack_end_ = nullptr;
289 this->object_infos.resize(0);
290 this->binary_info = nullptr;
291 this->libsimgrid_info = nullptr;
293 std::vector<simgrid::xbt::VmMap> const& maps = this->memory_map_;
295 const char* current_name = nullptr;
297 this->object_infos.clear();
299 for (size_t i = 0; i < maps.size(); i++) {
300 simgrid::xbt::VmMap const& reg = maps[i];
301 const char* pathname = maps[i].pathname.c_str();
304 if (maps[i].pathname.empty()) {
305 current_name = nullptr;
309 // [stack], [vvar], [vsyscall], [vdso] ...
310 if (pathname[0] == '[') {
311 if ((reg.prot & PROT_WRITE) && not memcmp(pathname, "[stack]", 7)) {
312 this->maestro_stack_start_ = remote(reg.start_addr);
313 this->maestro_stack_end_ = remote(reg.end_addr);
315 current_name = nullptr;
319 if (current_name && strcmp(current_name, pathname) == 0)
322 current_name = pathname;
323 if (not(reg.prot & PROT_READ) && (reg.prot & PROT_EXEC))
326 const bool is_executable = not i;
328 if (not is_executable) {
329 libname = get_lib_name(pathname);
330 if (is_filtered_lib(libname)) {
335 std::shared_ptr<simgrid::mc::ObjectInformation> info =
336 simgrid::mc::createObjectInformation(this->memory_map_, pathname);
337 this->object_infos.push_back(info);
339 this->binary_info = info;
340 else if (is_simgrid_lib(libname))
341 this->libsimgrid_info = info;
344 // Resolve time (including across different objects):
345 for (auto const& object_info : this->object_infos)
346 postProcessObjectInformation(this, object_info.get());
348 xbt_assert(this->maestro_stack_start_, "Did not find maestro_stack_start");
349 xbt_assert(this->maestro_stack_end_, "Did not find maestro_stack_end");
351 XBT_DEBUG("Get debug information done !");
354 std::shared_ptr<simgrid::mc::ObjectInformation> RemoteClient::find_object_info(RemotePtr<void> addr) const
356 for (auto const& object_info : this->object_infos)
357 if (addr.address() >= (std::uint64_t)object_info->start && addr.address() <= (std::uint64_t)object_info->end)
362 std::shared_ptr<ObjectInformation> RemoteClient::find_object_info_exec(RemotePtr<void> addr) const
364 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
365 if (addr.address() >= (std::uint64_t)info->start_exec && addr.address() <= (std::uint64_t)info->end_exec)
370 std::shared_ptr<ObjectInformation> RemoteClient::find_object_info_rw(RemotePtr<void> addr) const
372 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
373 if (addr.address() >= (std::uint64_t)info->start_rw && addr.address() <= (std::uint64_t)info->end_rw)
378 simgrid::mc::Frame* RemoteClient::find_function(RemotePtr<void> ip) const
380 std::shared_ptr<simgrid::mc::ObjectInformation> info = this->find_object_info_exec(ip);
381 return info ? info->find_function((void*)ip.address()) : nullptr;
384 /** Find (one occurrence of) the named variable definition
386 simgrid::mc::Variable* RemoteClient::find_variable(const char* name) const
388 // First lookup the variable in the executable shared object.
389 // A global variable used directly by the executable code from a library
390 // is reinstanciated in the executable memory .data/.bss.
391 // We need to look up the variable in the executable first.
392 if (this->binary_info) {
393 std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->binary_info;
394 simgrid::mc::Variable* var = info->find_variable(name);
399 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos) {
400 simgrid::mc::Variable* var = info->find_variable(name);
408 void RemoteClient::read_variable(const char* name, void* target, size_t size) const
410 simgrid::mc::Variable* var = this->find_variable(name);
411 xbt_assert(var->address, "No simple location for this variable");
412 xbt_assert(var->type->full_type, "Partial type for %s, cannot check size", name);
413 xbt_assert((size_t)var->type->full_type->byte_size == size, "Unexpected size for %s (expected %zu, was %zu)", name,
414 size, (size_t)var->type->full_type->byte_size);
415 this->read_bytes(target, size, remote(var->address));
418 std::string RemoteClient::read_string(RemotePtr<char> address) const
423 std::vector<char> res(128);
427 ssize_t c = pread(this->memory_file, res.data() + off, res.size() - off, (off_t)address.address() + off);
432 xbt_die("Could not read from from remote process");
435 xbt_die("Could not read string from remote process");
437 void* p = memchr(res.data() + off, '\0', c);
439 return std::string(res.data());
442 if (off == (off_t)res.size())
443 res.resize(res.size() * 2);
447 const void* RemoteClient::read_bytes(void* buffer, std::size_t size, RemotePtr<void> address, int process_index,
448 ReadOptions options) const
450 if (process_index != simgrid::mc::ProcessIndexDisabled) {
451 std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->find_object_info_rw(address);
452 // Segment overlap is not handled.
454 if (info.get() && this->privatized(*info)) {
455 if (process_index < 0)
456 xbt_die("Missing process index");
457 if (process_index >= (int)MC_smpi_process_count())
458 xbt_die("Invalid process index");
460 // Read smpi_privatization_regions from MCed:
461 smpi_privatization_region_t remote_smpi_privatization_regions =
462 mc_model_checker->process().read_variable<smpi_privatization_region_t>("smpi_privatization_regions");
464 s_smpi_privatization_region_t privatization_region =
465 mc_model_checker->process().read<s_smpi_privatization_region_t>(
466 remote(remote_smpi_privatization_regions + process_index));
468 // Address translation in the privatization segment:
469 size_t offset = address.address() - (std::uint64_t)info->start_rw;
470 address = remote((char*)privatization_region.address + offset);
474 if (pread_whole(this->memory_file, buffer, size, (size_t)address.address()) < 0)
475 xbt_die("Read at %p from process %lli failed", (void*)address.address(), (long long)this->pid_);
479 /** Write data to a process memory
481 * @param buffer local memory address (source)
482 * @param len data size
483 * @param address target process memory address (target)
485 void RemoteClient::write_bytes(const void* buffer, size_t len, RemotePtr<void> address)
487 if (pwrite_whole(this->memory_file, buffer, len, (size_t)address.address()) < 0)
488 xbt_die("Write to process %lli failed", (long long)this->pid_);
491 void RemoteClient::clear_bytes(RemotePtr<void> address, size_t len)
493 pthread_once(&zero_buffer_flag, zero_buffer_init);
495 size_t s = len > zero_buffer_size ? zero_buffer_size : len;
496 this->write_bytes(zero_buffer, s, address);
497 address = remote((char*)address.address() + s);
502 void RemoteClient::ignore_region(std::uint64_t addr, std::size_t size)
504 IgnoredRegion region;
508 if (ignored_regions_.empty()) {
509 ignored_regions_.push_back(region);
513 unsigned int cursor = 0;
514 IgnoredRegion* current_region = nullptr;
517 int end = ignored_regions_.size() - 1;
518 while (start <= end) {
519 cursor = (start + end) / 2;
520 current_region = &ignored_regions_[cursor];
521 if (current_region->addr == addr) {
522 if (current_region->size == size)
524 else if (current_region->size < size)
528 } else if (current_region->addr < addr)
534 std::size_t position;
535 if (current_region->addr == addr) {
536 if (current_region->size < size)
537 position = cursor + 1;
540 } else if (current_region->addr < addr)
541 position = cursor + 1;
544 ignored_regions_.insert(ignored_regions_.begin() + position, region);
547 void RemoteClient::ignore_heap(IgnoredHeapRegion const& region)
549 if (ignored_heap_.empty()) {
550 ignored_heap_.push_back(std::move(region));
554 typedef std::vector<IgnoredHeapRegion>::size_type size_type;
557 size_type end = ignored_heap_.size() - 1;
559 // Binary search the position of insertion:
561 while (start <= end) {
562 cursor = start + (end - start) / 2;
563 auto& current_region = ignored_heap_[cursor];
564 if (current_region.address == region.address)
566 else if (current_region.address < region.address)
568 else if (cursor != 0)
575 // Insert it mc_heap_ignore_region_t:
576 if (ignored_heap_[cursor].address < region.address)
578 ignored_heap_.insert(ignored_heap_.begin() + cursor, region);
581 void RemoteClient::unignore_heap(void* address, size_t size)
583 typedef std::vector<IgnoredHeapRegion>::size_type size_type;
586 size_type end = ignored_heap_.size() - 1;
590 while (start <= end) {
591 cursor = (start + end) / 2;
592 auto& region = ignored_heap_[cursor];
593 if (region.address < address)
595 else if ((char*)region.address <= ((char*)address + size)) {
596 ignored_heap_.erase(ignored_heap_.begin() + cursor);
598 } else if (cursor != 0)
606 void RemoteClient::ignore_local_variable(const char* var_name, const char* frame_name)
608 if (frame_name != nullptr && strcmp(frame_name, "*") == 0)
609 frame_name = nullptr;
610 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos)
611 info->remove_local_variable(var_name, frame_name);
614 std::vector<simgrid::mc::ActorInformation>& RemoteClient::actors()
616 this->refresh_simix();
617 return smx_actors_infos;
620 std::vector<simgrid::mc::ActorInformation>& RemoteClient::dead_actors()
622 this->refresh_simix();
623 return smx_dead_actors_infos;
626 void RemoteClient::dumpStack()
628 unw_addr_space_t as = unw_create_addr_space(&_UPT_accessors, BYTE_ORDER);
630 XBT_ERROR("Could not initialize ptrace address space");
634 void* context = _UPT_create(this->pid_);
635 if (context == nullptr) {
636 unw_destroy_addr_space(as);
637 XBT_ERROR("Could not initialize ptrace context");
642 if (unw_init_remote(&cursor, as, context) != 0) {
643 _UPT_destroy(context);
644 unw_destroy_addr_space(as);
645 XBT_ERROR("Could not initialiez ptrace cursor");
649 simgrid::mc::dumpStack(stderr, cursor);
651 _UPT_destroy(context);
652 unw_destroy_addr_space(as);
655 bool RemoteClient::actor_is_enabled(aid_t pid)
657 s_mc_message_actor_enabled_t 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_t), "Unexpected size in answer to ACTOR_ENABLED");
662 return ((s_mc_message_int_t*)buff)->value;