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",
105 static bool is_simgrid_lib(const std::string& libname)
107 return libname == "libsimgrid";
110 static bool is_filtered_lib(const std::string& libname)
112 return std::find(begin(filtered_libraries), end(filtered_libraries), libname) != end(filtered_libraries);
115 static std::string get_lib_name(const std::string& pathname)
117 std::string map_basename = simgrid::xbt::Path(pathname).get_base_name();
120 size_t pos = map_basename.rfind(".so");
121 if (pos != std::string::npos) {
122 // strip the extension (matching regex "\.so.*$")
123 libname.assign(map_basename, 0, pos);
125 // strip the version suffix (matching regex "-[.0-9-]*$")
127 pos = libname.rfind('-');
128 if (pos == std::string::npos || libname.find_first_not_of(".0123456789", pos + 1) != std::string::npos)
137 static ssize_t pread_whole(int fd, void* buf, size_t count, off_t offset)
139 char* buffer = (char*)buf;
140 ssize_t real_count = count;
142 ssize_t res = pread(fd, buffer, count, offset);
149 else if (errno != EINTR) {
150 perror("pread_whole");
157 static ssize_t pwrite_whole(int fd, const void* buf, size_t count, off_t offset)
159 const char* buffer = (const char*)buf;
160 ssize_t real_count = count;
162 ssize_t res = pwrite(fd, buffer, count, offset);
169 else if (errno != EINTR)
175 static pthread_once_t zero_buffer_flag = PTHREAD_ONCE_INIT;
176 static const void* zero_buffer;
177 static const size_t zero_buffer_size = 10 * 4096;
179 static void zero_buffer_init()
181 int fd = open("/dev/zero", O_RDONLY);
183 xbt_die("Could not open /dev/zero");
184 zero_buffer = mmap(nullptr, zero_buffer_size, PROT_READ, MAP_SHARED, fd, 0);
185 if (zero_buffer == MAP_FAILED)
186 xbt_die("Could not map the zero buffer");
190 int open_vm(pid_t pid, int flags)
192 const size_t buffer_size = 30;
193 char buffer[buffer_size];
194 int res = snprintf(buffer, buffer_size, "/proc/%lli/mem", (long long)pid);
195 if (res < 0 || (size_t)res >= buffer_size) {
196 errno = ENAMETOOLONG;
199 return open(buffer, flags);
204 RemoteClient::RemoteClient(pid_t pid, int sockfd) : AddressSpace(this), pid_(pid), channel_(sockfd), running_(true)
208 void RemoteClient::init()
210 this->memory_map_ = simgrid::xbt::get_memory_map(this->pid_);
211 this->init_memory_map_info();
213 int fd = open_vm(this->pid_, O_RDWR);
215 xbt_die("Could not open file for process virtual address space");
216 this->memory_file = fd;
218 // Read std_heap (is a struct mdesc*):
219 simgrid::mc::Variable* std_heap_var = this->find_variable("__mmalloc_default_mdp");
220 if (not std_heap_var)
221 xbt_die("No heap information in the target process");
222 if (not std_heap_var->address)
223 xbt_die("No constant address for this variable");
224 this->read_bytes(&this->heap_address, sizeof(mdesc*), remote(std_heap_var->address),
225 simgrid::mc::ProcessIndexDisabled);
227 this->smx_actors_infos.clear();
228 this->smx_dead_actors_infos.clear();
229 this->unw_addr_space = simgrid::mc::UnwindContext::createUnwindAddressSpace();
230 this->unw_underlying_addr_space = simgrid::unw::create_addr_space();
231 this->unw_underlying_context = simgrid::unw::create_context(this->unw_underlying_addr_space, this->pid_);
234 RemoteClient::~RemoteClient()
236 if (this->memory_file >= 0)
237 close(this->memory_file);
239 if (this->unw_underlying_addr_space != unw_local_addr_space) {
240 if (this->unw_underlying_addr_space)
241 unw_destroy_addr_space(this->unw_underlying_addr_space);
242 if (this->unw_underlying_context)
243 _UPT_destroy(this->unw_underlying_context);
246 unw_destroy_addr_space(this->unw_addr_space);
249 /** Refresh the information about the process
251 * Do not use directly, this is used by the getters when appropriate
252 * in order to have fresh data.
254 void RemoteClient::refresh_heap()
256 // Read/dereference/refresh the std_heap pointer:
258 this->heap = std::unique_ptr<s_xbt_mheap_t>(new s_xbt_mheap_t());
259 this->read_bytes(this->heap.get(), sizeof(mdesc), remote(this->heap_address), simgrid::mc::ProcessIndexDisabled);
260 this->cache_flags_ |= RemoteClient::cache_heap;
263 /** Refresh the information about the process
265 * Do not use direclty, this is used by the getters when appropriate
266 * in order to have fresh data.
268 void RemoteClient::refresh_malloc_info()
270 // Refresh process->heapinfo:
271 if (this->cache_flags_ & RemoteClient::cache_malloc)
273 size_t count = this->heap->heaplimit + 1;
274 if (this->heap_info.size() < count)
275 this->heap_info.resize(count);
276 this->read_bytes(this->heap_info.data(), count * sizeof(malloc_info), remote(this->heap->heapinfo),
277 simgrid::mc::ProcessIndexDisabled);
278 this->cache_flags_ |= RemoteClient::cache_malloc;
281 /** @brief Finds the range of the different memory segments and binary paths */
282 void RemoteClient::init_memory_map_info()
284 XBT_DEBUG("Get debug information ...");
285 this->maestro_stack_start_ = nullptr;
286 this->maestro_stack_end_ = nullptr;
287 this->object_infos.resize(0);
288 this->binary_info = nullptr;
289 this->libsimgrid_info = nullptr;
291 std::vector<simgrid::xbt::VmMap> const& maps = this->memory_map_;
293 const char* current_name = nullptr;
295 this->object_infos.clear();
297 for (size_t i = 0; i < maps.size(); i++) {
298 simgrid::xbt::VmMap const& reg = maps[i];
299 const char* pathname = maps[i].pathname.c_str();
302 if (maps[i].pathname.empty()) {
303 current_name = nullptr;
307 // [stack], [vvar], [vsyscall], [vdso] ...
308 if (pathname[0] == '[') {
309 if ((reg.prot & PROT_WRITE) && not memcmp(pathname, "[stack]", 7)) {
310 this->maestro_stack_start_ = remote(reg.start_addr);
311 this->maestro_stack_end_ = remote(reg.end_addr);
313 current_name = nullptr;
317 if (current_name && strcmp(current_name, pathname) == 0)
320 current_name = pathname;
321 if (not(reg.prot & PROT_READ) && (reg.prot & PROT_EXEC))
324 const bool is_executable = not i;
326 if (not is_executable) {
327 libname = get_lib_name(pathname);
328 if (is_filtered_lib(libname)) {
333 std::shared_ptr<simgrid::mc::ObjectInformation> info =
334 simgrid::mc::createObjectInformation(this->memory_map_, pathname);
335 this->object_infos.push_back(info);
337 this->binary_info = info;
338 else if (is_simgrid_lib(libname))
339 this->libsimgrid_info = info;
342 // Resolve time (including across different objects):
343 for (auto const& object_info : this->object_infos)
344 postProcessObjectInformation(this, object_info.get());
346 xbt_assert(this->maestro_stack_start_, "Did not find maestro_stack_start");
347 xbt_assert(this->maestro_stack_end_, "Did not find maestro_stack_end");
349 XBT_DEBUG("Get debug information done !");
352 std::shared_ptr<simgrid::mc::ObjectInformation> RemoteClient::find_object_info(RemotePtr<void> addr) const
354 for (auto const& object_info : this->object_infos)
355 if (addr.address() >= (std::uint64_t)object_info->start && addr.address() <= (std::uint64_t)object_info->end)
360 std::shared_ptr<ObjectInformation> RemoteClient::find_object_info_exec(RemotePtr<void> addr) const
362 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
363 if (addr.address() >= (std::uint64_t)info->start_exec && addr.address() <= (std::uint64_t)info->end_exec)
368 std::shared_ptr<ObjectInformation> RemoteClient::find_object_info_rw(RemotePtr<void> addr) const
370 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
371 if (addr.address() >= (std::uint64_t)info->start_rw && addr.address() <= (std::uint64_t)info->end_rw)
376 simgrid::mc::Frame* RemoteClient::find_function(RemotePtr<void> ip) const
378 std::shared_ptr<simgrid::mc::ObjectInformation> info = this->find_object_info_exec(ip);
379 return info ? info->find_function((void*)ip.address()) : nullptr;
382 /** Find (one occurrence of) the named variable definition
384 simgrid::mc::Variable* RemoteClient::find_variable(const char* name) const
386 // First lookup the variable in the executable shared object.
387 // A global variable used directly by the executable code from a library
388 // is reinstanciated in the executable memory .data/.bss.
389 // We need to look up the variable in the executable first.
390 if (this->binary_info) {
391 std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->binary_info;
392 simgrid::mc::Variable* var = info->find_variable(name);
397 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos) {
398 simgrid::mc::Variable* var = info->find_variable(name);
406 void RemoteClient::read_variable(const char* name, void* target, size_t size) const
408 simgrid::mc::Variable* var = this->find_variable(name);
409 xbt_assert(var->address, "No simple location for this variable");
410 xbt_assert(var->type->full_type, "Partial type for %s, cannot check size", name);
411 xbt_assert((size_t)var->type->full_type->byte_size == size, "Unexpected size for %s (expected %zu, was %zu)", name,
412 size, (size_t)var->type->full_type->byte_size);
413 this->read_bytes(target, size, remote(var->address));
416 std::string RemoteClient::read_string(RemotePtr<char> address) const
421 std::vector<char> res(128);
425 ssize_t c = pread(this->memory_file, res.data() + off, res.size() - off, (off_t)address.address() + off);
430 xbt_die("Could not read from from remote process");
433 xbt_die("Could not read string from remote process");
435 void* p = memchr(res.data() + off, '\0', c);
437 return std::string(res.data());
440 if (off == (off_t)res.size())
441 res.resize(res.size() * 2);
445 const void* RemoteClient::read_bytes(void* buffer, std::size_t size, RemotePtr<void> address, int process_index,
446 ReadOptions options) const
448 if (process_index != simgrid::mc::ProcessIndexDisabled) {
449 std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->find_object_info_rw(address);
450 // Segment overlap is not handled.
452 if (info.get() && this->privatized(*info)) {
453 if (process_index < 0)
454 xbt_die("Missing process index");
455 if (process_index >= (int)MC_smpi_process_count())
456 xbt_die("Invalid process index");
458 // Read smpi_privatization_regions from MCed:
459 smpi_privatization_region_t remote_smpi_privatization_regions =
460 mc_model_checker->process().read_variable<smpi_privatization_region_t>("smpi_privatization_regions");
462 s_smpi_privatization_region_t privatization_region =
463 mc_model_checker->process().read<s_smpi_privatization_region_t>(
464 remote(remote_smpi_privatization_regions + process_index));
466 // Address translation in the privatization segment:
467 size_t offset = address.address() - (std::uint64_t)info->start_rw;
468 address = remote((char*)privatization_region.address + offset);
472 if (pread_whole(this->memory_file, buffer, size, (size_t)address.address()) < 0)
473 xbt_die("Read at %p from process %lli failed", (void*)address.address(), (long long)this->pid_);
477 /** Write data to a process memory
479 * @param buffer local memory address (source)
480 * @param len data size
481 * @param address target process memory address (target)
483 void RemoteClient::write_bytes(const void* buffer, size_t len, RemotePtr<void> address)
485 if (pwrite_whole(this->memory_file, buffer, len, (size_t)address.address()) < 0)
486 xbt_die("Write to process %lli failed", (long long)this->pid_);
489 void RemoteClient::clear_bytes(RemotePtr<void> address, size_t len)
491 pthread_once(&zero_buffer_flag, zero_buffer_init);
493 size_t s = len > zero_buffer_size ? zero_buffer_size : len;
494 this->write_bytes(zero_buffer, s, address);
495 address = remote((char*)address.address() + s);
500 void RemoteClient::ignore_region(std::uint64_t addr, std::size_t size)
502 IgnoredRegion region;
506 if (ignored_regions_.empty()) {
507 ignored_regions_.push_back(region);
511 unsigned int cursor = 0;
512 IgnoredRegion* current_region = nullptr;
515 int end = ignored_regions_.size() - 1;
516 while (start <= end) {
517 cursor = (start + end) / 2;
518 current_region = &ignored_regions_[cursor];
519 if (current_region->addr == addr) {
520 if (current_region->size == size)
522 else if (current_region->size < size)
526 } else if (current_region->addr < addr)
532 std::size_t position;
533 if (current_region->addr == addr) {
534 if (current_region->size < size)
535 position = cursor + 1;
538 } else if (current_region->addr < addr)
539 position = cursor + 1;
542 ignored_regions_.insert(ignored_regions_.begin() + position, region);
545 void RemoteClient::ignore_heap(IgnoredHeapRegion const& region)
547 if (ignored_heap_.empty()) {
548 ignored_heap_.push_back(std::move(region));
552 typedef std::vector<IgnoredHeapRegion>::size_type size_type;
555 size_type end = ignored_heap_.size() - 1;
557 // Binary search the position of insertion:
559 while (start <= end) {
560 cursor = start + (end - start) / 2;
561 auto& current_region = ignored_heap_[cursor];
562 if (current_region.address == region.address)
564 else if (current_region.address < region.address)
566 else if (cursor != 0)
573 // Insert it mc_heap_ignore_region_t:
574 if (ignored_heap_[cursor].address < region.address)
576 ignored_heap_.insert(ignored_heap_.begin() + cursor, region);
579 void RemoteClient::unignore_heap(void* address, size_t size)
581 typedef std::vector<IgnoredHeapRegion>::size_type size_type;
584 size_type end = ignored_heap_.size() - 1;
588 while (start <= end) {
589 cursor = (start + end) / 2;
590 auto& region = ignored_heap_[cursor];
591 if (region.address < address)
593 else if ((char*)region.address <= ((char*)address + size)) {
594 ignored_heap_.erase(ignored_heap_.begin() + cursor);
596 } else if (cursor != 0)
604 void RemoteClient::ignore_local_variable(const char* var_name, const char* frame_name)
606 if (frame_name != nullptr && strcmp(frame_name, "*") == 0)
607 frame_name = nullptr;
608 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos)
609 info->remove_local_variable(var_name, frame_name);
612 std::vector<simgrid::mc::ActorInformation>& RemoteClient::actors()
614 this->refresh_simix();
615 return smx_actors_infos;
618 std::vector<simgrid::mc::ActorInformation>& RemoteClient::dead_actors()
620 this->refresh_simix();
621 return smx_dead_actors_infos;
624 void RemoteClient::dumpStack()
626 unw_addr_space_t as = unw_create_addr_space(&_UPT_accessors, BYTE_ORDER);
628 XBT_ERROR("Could not initialize ptrace address space");
632 void* context = _UPT_create(this->pid_);
633 if (context == nullptr) {
634 unw_destroy_addr_space(as);
635 XBT_ERROR("Could not initialize ptrace context");
640 if (unw_init_remote(&cursor, as, context) != 0) {
641 _UPT_destroy(context);
642 unw_destroy_addr_space(as);
643 XBT_ERROR("Could not initialiez ptrace cursor");
647 simgrid::mc::dumpStack(stderr, cursor);
649 _UPT_destroy(context);
650 unw_destroy_addr_space(as);
653 bool RemoteClient::actor_is_enabled(aid_t pid)
655 s_mc_message_actor_enabled_t msg{MC_MESSAGE_ACTOR_ENABLED, pid};
656 process()->getChannel().send(msg);
657 char buff[MC_MESSAGE_LENGTH];
658 ssize_t received = process()->getChannel().receive(buff, MC_MESSAGE_LENGTH, true);
659 xbt_assert(received == sizeof(s_mc_message_int_t), "Unexpected size in answer to ACTOR_ENABLED");
660 return ((s_mc_message_int_t*)buff)->value;