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_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",
104 "libboost_unit_test_framework"};
106 static bool is_simgrid_lib(const std::string& libname)
108 return libname == "libsimgrid";
111 static bool is_filtered_lib(const std::string& libname)
113 return std::find(begin(filtered_libraries), end(filtered_libraries), libname) != end(filtered_libraries);
116 static std::string get_lib_name(const std::string& pathname)
118 std::string map_basename = simgrid::xbt::Path(pathname).get_base_name();
121 size_t pos = map_basename.rfind(".so");
122 if (pos != std::string::npos) {
123 // strip the extension (matching regex "\.so.*$")
124 libname.assign(map_basename, 0, pos);
126 // strip the version suffix (matching regex "-[.0-9-]*$")
128 pos = libname.rfind('-');
129 if (pos == std::string::npos || libname.find_first_not_of(".0123456789", pos + 1) != std::string::npos)
138 static ssize_t pread_whole(int fd, void* buf, size_t count, off_t offset)
140 char* buffer = (char*)buf;
141 ssize_t real_count = count;
143 ssize_t res = pread(fd, buffer, count, offset);
150 else if (errno != EINTR) {
151 perror("pread_whole");
158 static ssize_t pwrite_whole(int fd, const void* buf, size_t count, off_t offset)
160 const char* buffer = (const char*)buf;
161 ssize_t real_count = count;
163 ssize_t res = pwrite(fd, buffer, count, offset);
170 else if (errno != EINTR)
176 static pthread_once_t zero_buffer_flag = PTHREAD_ONCE_INIT;
177 static const void* zero_buffer;
178 static const size_t zero_buffer_size = 10 * 4096;
180 static void zero_buffer_init()
182 int fd = open("/dev/zero", O_RDONLY);
184 xbt_die("Could not open /dev/zero");
185 zero_buffer = mmap(nullptr, zero_buffer_size, PROT_READ, MAP_SHARED, fd, 0);
186 if (zero_buffer == MAP_FAILED)
187 xbt_die("Could not map the zero buffer");
191 int open_vm(pid_t pid, int flags)
193 const size_t buffer_size = 30;
194 char buffer[buffer_size];
195 int res = snprintf(buffer, buffer_size, "/proc/%lli/mem", (long long)pid);
196 if (res < 0 || (size_t)res >= buffer_size) {
197 errno = ENAMETOOLONG;
200 return open(buffer, flags);
205 RemoteClient::RemoteClient(pid_t pid, int sockfd) : AddressSpace(this), pid_(pid), channel_(sockfd), running_(true)
209 void RemoteClient::init()
211 this->memory_map_ = simgrid::xbt::get_memory_map(this->pid_);
212 this->init_memory_map_info();
214 int fd = open_vm(this->pid_, O_RDWR);
216 xbt_die("Could not open file for process virtual address space");
217 this->memory_file = fd;
219 // Read std_heap (is a struct mdesc*):
220 simgrid::mc::Variable* std_heap_var = this->find_variable("__mmalloc_default_mdp");
221 if (not std_heap_var)
222 xbt_die("No heap information in the target process");
223 if (not std_heap_var->address)
224 xbt_die("No constant address for this variable");
225 this->read_bytes(&this->heap_address, sizeof(mdesc*), remote(std_heap_var->address),
226 simgrid::mc::ProcessIndexDisabled);
228 this->smx_actors_infos.clear();
229 this->smx_dead_actors_infos.clear();
230 this->unw_addr_space = simgrid::mc::UnwindContext::createUnwindAddressSpace();
231 this->unw_underlying_addr_space = simgrid::unw::create_addr_space();
232 this->unw_underlying_context = simgrid::unw::create_context(this->unw_underlying_addr_space, this->pid_);
235 RemoteClient::~RemoteClient()
237 if (this->memory_file >= 0)
238 close(this->memory_file);
240 if (this->unw_underlying_addr_space != unw_local_addr_space) {
241 if (this->unw_underlying_addr_space)
242 unw_destroy_addr_space(this->unw_underlying_addr_space);
243 if (this->unw_underlying_context)
244 _UPT_destroy(this->unw_underlying_context);
247 unw_destroy_addr_space(this->unw_addr_space);
250 /** Refresh the information about the process
252 * Do not use directly, this is used by the getters when appropriate
253 * in order to have fresh data.
255 void RemoteClient::refresh_heap()
257 // Read/dereference/refresh the std_heap pointer:
259 this->heap = std::unique_ptr<s_xbt_mheap_t>(new s_xbt_mheap_t());
260 this->read_bytes(this->heap.get(), sizeof(mdesc), remote(this->heap_address), simgrid::mc::ProcessIndexDisabled);
261 this->cache_flags_ |= RemoteClient::cache_heap;
264 /** Refresh the information about the process
266 * Do not use direclty, this is used by the getters when appropriate
267 * in order to have fresh data.
269 void RemoteClient::refresh_malloc_info()
271 // Refresh process->heapinfo:
272 if (this->cache_flags_ & RemoteClient::cache_malloc)
274 size_t count = this->heap->heaplimit + 1;
275 if (this->heap_info.size() < count)
276 this->heap_info.resize(count);
277 this->read_bytes(this->heap_info.data(), count * sizeof(malloc_info), remote(this->heap->heapinfo),
278 simgrid::mc::ProcessIndexDisabled);
279 this->cache_flags_ |= RemoteClient::cache_malloc;
282 /** @brief Finds the range of the different memory segments and binary paths */
283 void RemoteClient::init_memory_map_info()
285 XBT_DEBUG("Get debug information ...");
286 this->maestro_stack_start_ = nullptr;
287 this->maestro_stack_end_ = nullptr;
288 this->object_infos.resize(0);
289 this->binary_info = nullptr;
290 this->libsimgrid_info = nullptr;
292 std::vector<simgrid::xbt::VmMap> const& maps = this->memory_map_;
294 const char* current_name = nullptr;
296 this->object_infos.clear();
298 for (size_t i = 0; i < maps.size(); i++) {
299 simgrid::xbt::VmMap const& reg = maps[i];
300 const char* pathname = maps[i].pathname.c_str();
303 if (maps[i].pathname.empty()) {
304 current_name = nullptr;
308 // [stack], [vvar], [vsyscall], [vdso] ...
309 if (pathname[0] == '[') {
310 if ((reg.prot & PROT_WRITE) && not memcmp(pathname, "[stack]", 7)) {
311 this->maestro_stack_start_ = remote(reg.start_addr);
312 this->maestro_stack_end_ = remote(reg.end_addr);
314 current_name = nullptr;
318 if (current_name && strcmp(current_name, pathname) == 0)
321 current_name = pathname;
322 if (not(reg.prot & PROT_READ) && (reg.prot & PROT_EXEC))
325 const bool is_executable = not i;
327 if (not is_executable) {
328 libname = get_lib_name(pathname);
329 if (is_filtered_lib(libname)) {
334 std::shared_ptr<simgrid::mc::ObjectInformation> info =
335 simgrid::mc::createObjectInformation(this->memory_map_, pathname);
336 this->object_infos.push_back(info);
338 this->binary_info = info;
339 else if (is_simgrid_lib(libname))
340 this->libsimgrid_info = info;
343 // Resolve time (including across different objects):
344 for (auto const& object_info : this->object_infos)
345 postProcessObjectInformation(this, object_info.get());
347 xbt_assert(this->maestro_stack_start_, "Did not find maestro_stack_start");
348 xbt_assert(this->maestro_stack_end_, "Did not find maestro_stack_end");
350 XBT_DEBUG("Get debug information done !");
353 std::shared_ptr<simgrid::mc::ObjectInformation> RemoteClient::find_object_info(RemotePtr<void> addr) const
355 for (auto const& object_info : this->object_infos)
356 if (addr.address() >= (std::uint64_t)object_info->start && addr.address() <= (std::uint64_t)object_info->end)
361 std::shared_ptr<ObjectInformation> RemoteClient::find_object_info_exec(RemotePtr<void> addr) const
363 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
364 if (addr.address() >= (std::uint64_t)info->start_exec && addr.address() <= (std::uint64_t)info->end_exec)
369 std::shared_ptr<ObjectInformation> RemoteClient::find_object_info_rw(RemotePtr<void> addr) const
371 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
372 if (addr.address() >= (std::uint64_t)info->start_rw && addr.address() <= (std::uint64_t)info->end_rw)
377 simgrid::mc::Frame* RemoteClient::find_function(RemotePtr<void> ip) const
379 std::shared_ptr<simgrid::mc::ObjectInformation> info = this->find_object_info_exec(ip);
380 return info ? info->find_function((void*)ip.address()) : nullptr;
383 /** Find (one occurrence of) the named variable definition
385 simgrid::mc::Variable* RemoteClient::find_variable(const char* name) const
387 // First lookup the variable in the executable shared object.
388 // A global variable used directly by the executable code from a library
389 // is reinstanciated in the executable memory .data/.bss.
390 // We need to look up the variable in the executable first.
391 if (this->binary_info) {
392 std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->binary_info;
393 simgrid::mc::Variable* var = info->find_variable(name);
398 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos) {
399 simgrid::mc::Variable* var = info->find_variable(name);
407 void RemoteClient::read_variable(const char* name, void* target, size_t size) const
409 simgrid::mc::Variable* var = this->find_variable(name);
410 xbt_assert(var->address, "No simple location for this variable");
411 xbt_assert(var->type->full_type, "Partial type for %s, cannot check size", name);
412 xbt_assert((size_t)var->type->full_type->byte_size == size, "Unexpected size for %s (expected %zu, was %zu)", name,
413 size, (size_t)var->type->full_type->byte_size);
414 this->read_bytes(target, size, remote(var->address));
417 std::string RemoteClient::read_string(RemotePtr<char> address) const
422 std::vector<char> res(128);
426 ssize_t c = pread(this->memory_file, res.data() + off, res.size() - off, (off_t)address.address() + off);
431 xbt_die("Could not read from from remote process");
434 xbt_die("Could not read string from remote process");
436 void* p = memchr(res.data() + off, '\0', c);
438 return std::string(res.data());
441 if (off == (off_t)res.size())
442 res.resize(res.size() * 2);
446 const void* RemoteClient::read_bytes(void* buffer, std::size_t size, RemotePtr<void> address, int process_index,
447 ReadOptions options) const
449 if (process_index != simgrid::mc::ProcessIndexDisabled) {
450 std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->find_object_info_rw(address);
451 // Segment overlap is not handled.
453 if (info.get() && this->privatized(*info)) {
454 if (process_index < 0)
455 xbt_die("Missing process index");
456 if (process_index >= (int)MC_smpi_process_count())
457 xbt_die("Invalid process index");
459 // Read smpi_privatization_regions from MCed:
460 smpi_privatization_region_t remote_smpi_privatization_regions =
461 mc_model_checker->process().read_variable<smpi_privatization_region_t>("smpi_privatization_regions");
463 s_smpi_privatization_region_t privatization_region =
464 mc_model_checker->process().read<s_smpi_privatization_region_t>(
465 remote(remote_smpi_privatization_regions + process_index));
467 // Address translation in the privatization segment:
468 size_t offset = address.address() - (std::uint64_t)info->start_rw;
469 address = remote((char*)privatization_region.address + offset);
473 if (pread_whole(this->memory_file, buffer, size, (size_t)address.address()) < 0)
474 xbt_die("Read at %p from process %lli failed", (void*)address.address(), (long long)this->pid_);
478 /** Write data to a process memory
480 * @param buffer local memory address (source)
481 * @param len data size
482 * @param address target process memory address (target)
484 void RemoteClient::write_bytes(const void* buffer, size_t len, RemotePtr<void> address)
486 if (pwrite_whole(this->memory_file, buffer, len, (size_t)address.address()) < 0)
487 xbt_die("Write to process %lli failed", (long long)this->pid_);
490 void RemoteClient::clear_bytes(RemotePtr<void> address, size_t len)
492 pthread_once(&zero_buffer_flag, zero_buffer_init);
494 size_t s = len > zero_buffer_size ? zero_buffer_size : len;
495 this->write_bytes(zero_buffer, s, address);
496 address = remote((char*)address.address() + s);
501 void RemoteClient::ignore_region(std::uint64_t addr, std::size_t size)
503 IgnoredRegion region;
507 if (ignored_regions_.empty()) {
508 ignored_regions_.push_back(region);
512 unsigned int cursor = 0;
513 IgnoredRegion* current_region = nullptr;
516 int end = ignored_regions_.size() - 1;
517 while (start <= end) {
518 cursor = (start + end) / 2;
519 current_region = &ignored_regions_[cursor];
520 if (current_region->addr == addr) {
521 if (current_region->size == size)
523 else if (current_region->size < size)
527 } else if (current_region->addr < addr)
533 std::size_t position;
534 if (current_region->addr == addr) {
535 if (current_region->size < size)
536 position = cursor + 1;
539 } else if (current_region->addr < addr)
540 position = cursor + 1;
543 ignored_regions_.insert(ignored_regions_.begin() + position, region);
546 void RemoteClient::ignore_heap(IgnoredHeapRegion const& region)
548 if (ignored_heap_.empty()) {
549 ignored_heap_.push_back(std::move(region));
553 typedef std::vector<IgnoredHeapRegion>::size_type size_type;
556 size_type end = ignored_heap_.size() - 1;
558 // Binary search the position of insertion:
560 while (start <= end) {
561 cursor = start + (end - start) / 2;
562 auto& current_region = ignored_heap_[cursor];
563 if (current_region.address == region.address)
565 else if (current_region.address < region.address)
567 else if (cursor != 0)
574 // Insert it mc_heap_ignore_region_t:
575 if (ignored_heap_[cursor].address < region.address)
577 ignored_heap_.insert(ignored_heap_.begin() + cursor, region);
580 void RemoteClient::unignore_heap(void* address, size_t size)
582 typedef std::vector<IgnoredHeapRegion>::size_type size_type;
585 size_type end = ignored_heap_.size() - 1;
589 while (start <= end) {
590 cursor = (start + end) / 2;
591 auto& region = ignored_heap_[cursor];
592 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);
654 bool RemoteClient::actor_is_enabled(aid_t pid)
656 s_mc_message_actor_enabled_t msg{MC_MESSAGE_ACTOR_ENABLED, pid};
657 process()->getChannel().send(msg);
658 char buff[MC_MESSAGE_LENGTH];
659 ssize_t received = process()->getChannel().receive(buff, MC_MESSAGE_LENGTH, true);
660 xbt_assert(received == sizeof(s_mc_message_int_t), "Unexpected size in answer to ACTOR_ENABLED");
661 return ((s_mc_message_int_t*)buff)->value;