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 "libargp", /* workarounds for glibc-less systems */
68 "libasan", /* gcc sanitizers */
71 "libboost_context-mt",
75 "libboost_unit_test_framework",
107 "libtsan", /* gcc sanitizers */
108 "libubsan", /* gcc sanitizers */
115 static bool is_simgrid_lib(const std::string& libname)
117 return libname == "libsimgrid";
120 static bool is_filtered_lib(const std::string& libname)
122 return std::find(begin(filtered_libraries), end(filtered_libraries), libname) != end(filtered_libraries);
125 static std::string get_lib_name(const std::string& pathname)
127 std::string map_basename = simgrid::xbt::Path(pathname).get_base_name();
130 size_t pos = map_basename.rfind(".so");
131 if (pos != std::string::npos) {
132 // strip the extension (matching regex "\.so.*$")
133 libname.assign(map_basename, 0, pos);
135 // strip the version suffix (matching regex "-[.0-9-]*$")
137 pos = libname.rfind('-');
138 if (pos == std::string::npos || libname.find_first_not_of(".0123456789", pos + 1) != std::string::npos)
147 static ssize_t pread_whole(int fd, void* buf, size_t count, off_t offset)
149 char* buffer = (char*)buf;
150 ssize_t real_count = count;
152 ssize_t res = pread(fd, buffer, count, offset);
159 else if (errno != EINTR) {
160 perror("pread_whole");
167 static ssize_t pwrite_whole(int fd, const void* buf, size_t count, off_t offset)
169 const char* buffer = (const char*)buf;
170 ssize_t real_count = count;
172 ssize_t res = pwrite(fd, buffer, count, offset);
179 else if (errno != EINTR)
185 static pthread_once_t zero_buffer_flag = PTHREAD_ONCE_INIT;
186 static const void* zero_buffer;
187 static const size_t zero_buffer_size = 10 * 4096;
189 static void zero_buffer_init()
191 int fd = open("/dev/zero", O_RDONLY);
193 xbt_die("Could not open /dev/zero");
194 zero_buffer = mmap(nullptr, zero_buffer_size, PROT_READ, MAP_SHARED, fd, 0);
195 if (zero_buffer == MAP_FAILED)
196 xbt_die("Could not map the zero buffer");
200 int open_vm(pid_t pid, int flags)
202 const size_t buffer_size = 30;
203 char buffer[buffer_size];
204 int res = snprintf(buffer, buffer_size, "/proc/%lli/mem", (long long)pid);
205 if (res < 0 || (size_t)res >= buffer_size) {
206 errno = ENAMETOOLONG;
209 return open(buffer, flags);
214 RemoteClient::RemoteClient(pid_t pid, int sockfd) : AddressSpace(this), pid_(pid), channel_(sockfd), running_(true)
218 void RemoteClient::init()
220 this->memory_map_ = simgrid::xbt::get_memory_map(this->pid_);
221 this->init_memory_map_info();
223 int fd = open_vm(this->pid_, O_RDWR);
225 xbt_die("Could not open file for process virtual address space");
226 this->memory_file = fd;
228 // Read std_heap (is a struct mdesc*):
229 simgrid::mc::Variable* std_heap_var = this->find_variable("__mmalloc_default_mdp");
230 if (not std_heap_var)
231 xbt_die("No heap information in the target process");
232 if (not std_heap_var->address)
233 xbt_die("No constant address for this variable");
234 this->read_bytes(&this->heap_address, sizeof(mdesc*), remote(std_heap_var->address),
235 simgrid::mc::ProcessIndexDisabled);
237 this->smx_actors_infos.clear();
238 this->smx_dead_actors_infos.clear();
239 this->unw_addr_space = simgrid::mc::UnwindContext::createUnwindAddressSpace();
240 this->unw_underlying_addr_space = simgrid::unw::create_addr_space();
241 this->unw_underlying_context = simgrid::unw::create_context(this->unw_underlying_addr_space, this->pid_);
244 RemoteClient::~RemoteClient()
246 if (this->memory_file >= 0)
247 close(this->memory_file);
249 if (this->unw_underlying_addr_space != unw_local_addr_space) {
250 if (this->unw_underlying_addr_space)
251 unw_destroy_addr_space(this->unw_underlying_addr_space);
252 if (this->unw_underlying_context)
253 _UPT_destroy(this->unw_underlying_context);
256 unw_destroy_addr_space(this->unw_addr_space);
259 /** Refresh the information about the process
261 * Do not use directly, this is used by the getters when appropriate
262 * in order to have fresh data.
264 void RemoteClient::refresh_heap()
266 // Read/dereference/refresh the std_heap pointer:
268 this->heap = std::unique_ptr<s_xbt_mheap_t>(new s_xbt_mheap_t());
269 this->read_bytes(this->heap.get(), sizeof(mdesc), remote(this->heap_address), simgrid::mc::ProcessIndexDisabled);
270 this->cache_flags_ |= RemoteClient::cache_heap;
273 /** Refresh the information about the process
275 * Do not use direclty, this is used by the getters when appropriate
276 * in order to have fresh data.
278 void RemoteClient::refresh_malloc_info()
280 // Refresh process->heapinfo:
281 if (this->cache_flags_ & RemoteClient::cache_malloc)
283 size_t count = this->heap->heaplimit + 1;
284 if (this->heap_info.size() < count)
285 this->heap_info.resize(count);
286 this->read_bytes(this->heap_info.data(), count * sizeof(malloc_info), remote(this->heap->heapinfo),
287 simgrid::mc::ProcessIndexDisabled);
288 this->cache_flags_ |= RemoteClient::cache_malloc;
291 /** @brief Finds the range of the different memory segments and binary paths */
292 void RemoteClient::init_memory_map_info()
294 XBT_DEBUG("Get debug information ...");
295 this->maestro_stack_start_ = nullptr;
296 this->maestro_stack_end_ = nullptr;
297 this->object_infos.resize(0);
298 this->binary_info = nullptr;
299 this->libsimgrid_info = nullptr;
301 std::vector<simgrid::xbt::VmMap> const& maps = this->memory_map_;
303 const char* current_name = nullptr;
305 this->object_infos.clear();
307 for (size_t i = 0; i < maps.size(); i++) {
308 simgrid::xbt::VmMap const& reg = maps[i];
309 const char* pathname = maps[i].pathname.c_str();
312 if (maps[i].pathname.empty()) {
313 current_name = nullptr;
317 // [stack], [vvar], [vsyscall], [vdso] ...
318 if (pathname[0] == '[') {
319 if ((reg.prot & PROT_WRITE) && not memcmp(pathname, "[stack]", 7)) {
320 this->maestro_stack_start_ = remote(reg.start_addr);
321 this->maestro_stack_end_ = remote(reg.end_addr);
323 current_name = nullptr;
327 if (current_name && strcmp(current_name, pathname) == 0)
330 current_name = pathname;
331 if (not(reg.prot & PROT_READ) && (reg.prot & PROT_EXEC))
334 const bool is_executable = not i;
336 if (not is_executable) {
337 libname = get_lib_name(pathname);
338 if (is_filtered_lib(libname)) {
343 std::shared_ptr<simgrid::mc::ObjectInformation> info =
344 simgrid::mc::createObjectInformation(this->memory_map_, pathname);
345 this->object_infos.push_back(info);
347 this->binary_info = info;
348 else if (is_simgrid_lib(libname))
349 this->libsimgrid_info = info;
352 // Resolve time (including across different objects):
353 for (auto const& object_info : this->object_infos)
354 postProcessObjectInformation(this, object_info.get());
356 xbt_assert(this->maestro_stack_start_, "Did not find maestro_stack_start");
357 xbt_assert(this->maestro_stack_end_, "Did not find maestro_stack_end");
359 XBT_DEBUG("Get debug information done !");
362 std::shared_ptr<simgrid::mc::ObjectInformation> RemoteClient::find_object_info(RemotePtr<void> addr) const
364 for (auto const& object_info : this->object_infos)
365 if (addr.address() >= (std::uint64_t)object_info->start && addr.address() <= (std::uint64_t)object_info->end)
370 std::shared_ptr<ObjectInformation> RemoteClient::find_object_info_exec(RemotePtr<void> addr) const
372 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
373 if (addr.address() >= (std::uint64_t)info->start_exec && addr.address() <= (std::uint64_t)info->end_exec)
378 std::shared_ptr<ObjectInformation> RemoteClient::find_object_info_rw(RemotePtr<void> addr) const
380 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
381 if (addr.address() >= (std::uint64_t)info->start_rw && addr.address() <= (std::uint64_t)info->end_rw)
386 simgrid::mc::Frame* RemoteClient::find_function(RemotePtr<void> ip) const
388 std::shared_ptr<simgrid::mc::ObjectInformation> info = this->find_object_info_exec(ip);
389 return info ? info->find_function((void*)ip.address()) : nullptr;
392 /** Find (one occurrence of) the named variable definition
394 simgrid::mc::Variable* RemoteClient::find_variable(const char* name) const
396 // First lookup the variable in the executable shared object.
397 // A global variable used directly by the executable code from a library
398 // is reinstanciated in the executable memory .data/.bss.
399 // We need to look up the variable in the executable first.
400 if (this->binary_info) {
401 std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->binary_info;
402 simgrid::mc::Variable* var = info->find_variable(name);
407 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos) {
408 simgrid::mc::Variable* var = info->find_variable(name);
416 void RemoteClient::read_variable(const char* name, void* target, size_t size) const
418 simgrid::mc::Variable* var = this->find_variable(name);
419 xbt_assert(var->address, "No simple location for this variable");
420 xbt_assert(var->type->full_type, "Partial type for %s, cannot check size", name);
421 xbt_assert((size_t)var->type->full_type->byte_size == size, "Unexpected size for %s (expected %zu, was %zu)", name,
422 size, (size_t)var->type->full_type->byte_size);
423 this->read_bytes(target, size, remote(var->address));
426 std::string RemoteClient::read_string(RemotePtr<char> address) const
431 std::vector<char> res(128);
435 ssize_t c = pread(this->memory_file, res.data() + off, res.size() - off, (off_t)address.address() + off);
440 xbt_die("Could not read from from remote process");
443 xbt_die("Could not read string from remote process");
445 void* p = memchr(res.data() + off, '\0', c);
447 return std::string(res.data());
450 if (off == (off_t)res.size())
451 res.resize(res.size() * 2);
455 const void* RemoteClient::read_bytes(void* buffer, std::size_t size, RemotePtr<void> address, int process_index,
456 ReadOptions options) const
459 if (process_index != simgrid::mc::ProcessIndexDisabled) {
460 std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->find_object_info_rw(address);
461 // Segment overlap is not handled.
462 if (info.get() && this->privatized(*info)) {
463 if (process_index < 0)
464 xbt_die("Missing process index");
465 if (process_index >= (int)MC_smpi_process_count())
466 xbt_die("Invalid process index");
468 // Read smpi_privatization_regions from MCed:
469 smpi_privatization_region_t remote_smpi_privatization_regions =
470 mc_model_checker->process().read_variable<smpi_privatization_region_t>("smpi_privatization_regions");
472 s_smpi_privatization_region_t privatization_region =
473 mc_model_checker->process().read<s_smpi_privatization_region_t>(
474 remote(remote_smpi_privatization_regions + process_index));
476 // Address translation in the privatization segment:
477 size_t offset = address.address() - (std::uint64_t)info->start_rw;
478 address = remote((char*)privatization_region.address + offset);
482 if (pread_whole(this->memory_file, buffer, size, (size_t)address.address()) < 0)
483 xbt_die("Read at %p from process %lli failed", (void*)address.address(), (long long)this->pid_);
487 /** Write data to a process memory
489 * @param buffer local memory address (source)
490 * @param len data size
491 * @param address target process memory address (target)
493 void RemoteClient::write_bytes(const void* buffer, size_t len, RemotePtr<void> address)
495 if (pwrite_whole(this->memory_file, buffer, len, (size_t)address.address()) < 0)
496 xbt_die("Write to process %lli failed", (long long)this->pid_);
499 void RemoteClient::clear_bytes(RemotePtr<void> address, size_t len)
501 pthread_once(&zero_buffer_flag, zero_buffer_init);
503 size_t s = len > zero_buffer_size ? zero_buffer_size : len;
504 this->write_bytes(zero_buffer, s, address);
505 address = remote((char*)address.address() + s);
510 void RemoteClient::ignore_region(std::uint64_t addr, std::size_t size)
512 IgnoredRegion region;
516 if (ignored_regions_.empty()) {
517 ignored_regions_.push_back(region);
521 unsigned int cursor = 0;
522 IgnoredRegion* current_region = nullptr;
525 int end = ignored_regions_.size() - 1;
526 while (start <= end) {
527 cursor = (start + end) / 2;
528 current_region = &ignored_regions_[cursor];
529 if (current_region->addr == addr) {
530 if (current_region->size == size)
532 else if (current_region->size < size)
536 } else if (current_region->addr < addr)
542 std::size_t position;
543 if (current_region->addr == addr) {
544 if (current_region->size < size)
545 position = cursor + 1;
548 } else if (current_region->addr < addr)
549 position = cursor + 1;
552 ignored_regions_.insert(ignored_regions_.begin() + position, region);
555 void RemoteClient::ignore_heap(IgnoredHeapRegion const& region)
557 if (ignored_heap_.empty()) {
558 ignored_heap_.push_back(std::move(region));
562 typedef std::vector<IgnoredHeapRegion>::size_type size_type;
565 size_type end = ignored_heap_.size() - 1;
567 // Binary search the position of insertion:
569 while (start <= end) {
570 cursor = start + (end - start) / 2;
571 auto& current_region = ignored_heap_[cursor];
572 if (current_region.address == region.address)
574 else if (current_region.address < region.address)
576 else if (cursor != 0)
583 // Insert it mc_heap_ignore_region_t:
584 if (ignored_heap_[cursor].address < region.address)
586 ignored_heap_.insert(ignored_heap_.begin() + cursor, region);
589 void RemoteClient::unignore_heap(void* address, size_t size)
591 typedef std::vector<IgnoredHeapRegion>::size_type size_type;
594 size_type end = ignored_heap_.size() - 1;
598 while (start <= end) {
599 cursor = (start + end) / 2;
600 auto& region = ignored_heap_[cursor];
601 if (region.address < address)
603 else if ((char*)region.address <= ((char*)address + size)) {
604 ignored_heap_.erase(ignored_heap_.begin() + cursor);
606 } else if (cursor != 0)
614 void RemoteClient::ignore_local_variable(const char* var_name, const char* frame_name)
616 if (frame_name != nullptr && strcmp(frame_name, "*") == 0)
617 frame_name = nullptr;
618 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos)
619 info->remove_local_variable(var_name, frame_name);
622 std::vector<simgrid::mc::ActorInformation>& RemoteClient::actors()
624 this->refresh_simix();
625 return smx_actors_infos;
628 std::vector<simgrid::mc::ActorInformation>& RemoteClient::dead_actors()
630 this->refresh_simix();
631 return smx_dead_actors_infos;
634 void RemoteClient::dumpStack()
636 unw_addr_space_t as = unw_create_addr_space(&_UPT_accessors, BYTE_ORDER);
638 XBT_ERROR("Could not initialize ptrace address space");
642 void* context = _UPT_create(this->pid_);
643 if (context == nullptr) {
644 unw_destroy_addr_space(as);
645 XBT_ERROR("Could not initialize ptrace context");
650 if (unw_init_remote(&cursor, as, context) != 0) {
651 _UPT_destroy(context);
652 unw_destroy_addr_space(as);
653 XBT_ERROR("Could not initialiez ptrace cursor");
657 simgrid::mc::dumpStack(stderr, cursor);
659 _UPT_destroy(context);
660 unw_destroy_addr_space(as);
663 bool RemoteClient::actor_is_enabled(aid_t pid)
665 s_mc_message_actor_enabled_t msg{MC_MESSAGE_ACTOR_ENABLED, pid};
666 process()->getChannel().send(msg);
667 char buff[MC_MESSAGE_LENGTH];
668 ssize_t received = process()->getChannel().receive(buff, MC_MESSAGE_LENGTH, true);
669 xbt_assert(received == sizeof(s_mc_message_int_t), "Unexpected size in answer to ACTOR_ENABLED");
670 return ((s_mc_message_int_t*)buff)->value;