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 */
13 #include <sys/ptrace.h>
19 #include <sys/mman.h> // PROT_*
20 #include <sys/types.h>
27 #include <libunwind-ptrace.h>
28 #include <libunwind.h>
32 #include <xbt/mmalloc.h>
34 #include "src/mc/mc_smx.hpp"
35 #include "src/mc/mc_snapshot.hpp"
36 #include "src/mc/mc_unw.hpp"
38 #include "src/mc/AddressSpace.hpp"
39 #include "src/mc/ObjectInformation.hpp"
40 #include "src/mc/Variable.hpp"
41 #include "src/mc/remote/RemoteClient.hpp"
43 using simgrid::mc::remote;
45 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_process, mc, "MC process information");
49 #define SO_RE "\\.so[\\.0-9]*$"
50 #define VERSION_RE "-[\\.0-9-]*$"
55 // List of library which memory segments are not considered:
56 static const char* const 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 char* libname)
103 return not strcmp(libname, "libsimgrid");
106 static bool is_filtered_lib(const char* libname)
108 for (const char* const& filtered_lib : filtered_libraries)
109 if (strcmp(libname, filtered_lib) == 0)
114 struct s_mc_memory_map_re {
119 static char* get_lib_name(const char* pathname, s_mc_memory_map_re* res)
121 char* map_basename = xbt_basename(pathname);
124 if (regexec(&res->so_re, map_basename, 1, &match, 0)) {
129 char* libname = strndup(map_basename, match.rm_so);
131 map_basename = nullptr;
133 // Strip the version suffix:
134 if (libname && not regexec(&res->version_re, libname, 1, &match, 0)) {
135 char* temp = libname;
136 libname = strndup(temp, match.rm_so);
143 static ssize_t pread_whole(int fd, void* buf, size_t count, off_t offset)
145 char* buffer = (char*)buf;
146 ssize_t real_count = count;
148 ssize_t res = pread(fd, buffer, count, offset);
155 else if (errno != EINTR) {
156 perror("pread_whole");
163 static ssize_t pwrite_whole(int fd, const void* buf, size_t count, off_t offset)
165 const char* buffer = (const char*)buf;
166 ssize_t real_count = count;
168 ssize_t res = pwrite(fd, buffer, count, offset);
175 else if (errno != EINTR)
181 static pthread_once_t zero_buffer_flag = PTHREAD_ONCE_INIT;
182 static const void* zero_buffer;
183 static const size_t zero_buffer_size = 10 * 4096;
185 static void zero_buffer_init()
187 int fd = open("/dev/zero", O_RDONLY);
189 xbt_die("Could not open /dev/zero");
190 zero_buffer = mmap(nullptr, zero_buffer_size, PROT_READ, MAP_SHARED, fd, 0);
191 if (zero_buffer == MAP_FAILED)
192 xbt_die("Could not map the zero buffer");
196 int open_vm(pid_t pid, int flags)
198 const size_t buffer_size = 30;
199 char buffer[buffer_size];
200 int res = snprintf(buffer, buffer_size, "/proc/%lli/mem", (long long)pid);
201 if (res < 0 || (size_t)res >= buffer_size) {
202 errno = ENAMETOOLONG;
205 return open(buffer, flags);
210 RemoteClient::RemoteClient(pid_t pid, int sockfd) : AddressSpace(this), pid_(pid), channel_(sockfd), running_(true)
214 void RemoteClient::init()
216 this->memory_map_ = simgrid::xbt::get_memory_map(this->pid_);
217 this->init_memory_map_info();
219 int fd = open_vm(this->pid_, O_RDWR);
221 xbt_die("Could not open file for process virtual address space");
222 this->memory_file = fd;
224 // Read std_heap (is a struct mdesc*):
225 simgrid::mc::Variable* std_heap_var = this->find_variable("__mmalloc_default_mdp");
226 if (not std_heap_var)
227 xbt_die("No heap information in the target process");
228 if (not std_heap_var->address)
229 xbt_die("No constant address for this variable");
230 this->read_bytes(&this->heap_address, sizeof(mdesc*), remote(std_heap_var->address),
231 simgrid::mc::ProcessIndexDisabled);
233 this->smx_actors_infos.clear();
234 this->smx_dead_actors_infos.clear();
235 this->unw_addr_space = simgrid::mc::UnwindContext::createUnwindAddressSpace();
236 this->unw_underlying_addr_space = simgrid::unw::create_addr_space();
237 this->unw_underlying_context = simgrid::unw::create_context(this->unw_underlying_addr_space, this->pid_);
240 RemoteClient::~RemoteClient()
242 if (this->memory_file >= 0)
243 close(this->memory_file);
245 if (this->unw_underlying_addr_space != unw_local_addr_space) {
246 if (this->unw_underlying_addr_space)
247 unw_destroy_addr_space(this->unw_underlying_addr_space);
248 if (this->unw_underlying_context)
249 _UPT_destroy(this->unw_underlying_context);
252 unw_destroy_addr_space(this->unw_addr_space);
255 /** Refresh the information about the process
257 * Do not use directly, this is used by the getters when appropriate
258 * in order to have fresh data.
260 void RemoteClient::refresh_heap()
262 // Read/dereference/refresh the std_heap pointer:
264 this->heap = std::unique_ptr<s_xbt_mheap_t>(new s_xbt_mheap_t());
265 this->read_bytes(this->heap.get(), sizeof(mdesc), remote(this->heap_address), simgrid::mc::ProcessIndexDisabled);
266 this->cache_flags_ |= RemoteClient::cache_heap;
269 /** Refresh the information about the process
271 * Do not use direclty, this is used by the getters when appropriate
272 * in order to have fresh data.
274 void RemoteClient::refresh_malloc_info()
276 // Refresh process->heapinfo:
277 if (this->cache_flags_ & RemoteClient::cache_malloc)
279 size_t count = this->heap->heaplimit + 1;
280 if (this->heap_info.size() < count)
281 this->heap_info.resize(count);
282 this->read_bytes(this->heap_info.data(), count * sizeof(malloc_info), remote(this->heap->heapinfo),
283 simgrid::mc::ProcessIndexDisabled);
284 this->cache_flags_ |= RemoteClient::cache_malloc;
287 /** @brief Finds the range of the different memory segments and binary paths */
288 void RemoteClient::init_memory_map_info()
290 XBT_DEBUG("Get debug information ...");
291 this->maestro_stack_start_ = nullptr;
292 this->maestro_stack_end_ = nullptr;
293 this->object_infos.resize(0);
294 this->binary_info = nullptr;
295 this->libsimgrid_info = nullptr;
297 s_mc_memory_map_re res;
299 if (regcomp(&res.so_re, SO_RE, 0) || regcomp(&res.version_re, VERSION_RE, 0))
300 xbt_die(".so regexp did not compile");
302 std::vector<simgrid::xbt::VmMap> const& maps = this->memory_map_;
304 const char* current_name = nullptr;
306 this->object_infos.clear();
308 for (size_t i = 0; i < maps.size(); i++) {
309 simgrid::xbt::VmMap const& reg = maps[i];
310 const char* pathname = maps[i].pathname.c_str();
313 if (maps[i].pathname.empty()) {
314 current_name = nullptr;
318 // [stack], [vvar], [vsyscall], [vdso] ...
319 if (pathname[0] == '[') {
320 if ((reg.prot & PROT_WRITE) && not memcmp(pathname, "[stack]", 7)) {
321 this->maestro_stack_start_ = remote(reg.start_addr);
322 this->maestro_stack_end_ = remote(reg.end_addr);
324 current_name = nullptr;
328 if (current_name && strcmp(current_name, pathname) == 0)
331 current_name = pathname;
332 if (not(reg.prot & PROT_READ) && (reg.prot & PROT_EXEC))
335 const bool is_executable = not i;
336 char* libname = nullptr;
337 if (not is_executable) {
338 libname = get_lib_name(pathname, &res);
341 if (is_filtered_lib(libname)) {
347 std::shared_ptr<simgrid::mc::ObjectInformation> info =
348 simgrid::mc::createObjectInformation(this->memory_map_, pathname);
349 this->object_infos.push_back(info);
351 this->binary_info = info;
352 else if (libname && is_simgrid_lib(libname))
353 this->libsimgrid_info = info;
358 regfree(&res.version_re);
360 // Resolve time (including across different objects):
361 for (auto const& object_info : this->object_infos)
362 postProcessObjectInformation(this, object_info.get());
364 xbt_assert(this->maestro_stack_start_, "Did not find maestro_stack_start");
365 xbt_assert(this->maestro_stack_end_, "Did not find maestro_stack_end");
367 XBT_DEBUG("Get debug information done !");
370 std::shared_ptr<simgrid::mc::ObjectInformation> RemoteClient::find_object_info(RemotePtr<void> addr) const
372 for (auto const& object_info : this->object_infos)
373 if (addr.address() >= (std::uint64_t)object_info->start && addr.address() <= (std::uint64_t)object_info->end)
378 std::shared_ptr<ObjectInformation> RemoteClient::find_object_info_exec(RemotePtr<void> addr) const
380 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
381 if (addr.address() >= (std::uint64_t)info->start_exec && addr.address() <= (std::uint64_t)info->end_exec)
386 std::shared_ptr<ObjectInformation> RemoteClient::find_object_info_rw(RemotePtr<void> addr) const
388 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
389 if (addr.address() >= (std::uint64_t)info->start_rw && addr.address() <= (std::uint64_t)info->end_rw)
394 simgrid::mc::Frame* RemoteClient::find_function(RemotePtr<void> ip) const
396 std::shared_ptr<simgrid::mc::ObjectInformation> info = this->find_object_info_exec(ip);
397 return info ? info->find_function((void*)ip.address()) : nullptr;
400 /** Find (one occurrence of) the named variable definition
402 simgrid::mc::Variable* RemoteClient::find_variable(const char* name) const
404 // First lookup the variable in the executable shared object.
405 // A global variable used directly by the executable code from a library
406 // is reinstanciated in the executable memory .data/.bss.
407 // We need to look up the variable in the executable first.
408 if (this->binary_info) {
409 std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->binary_info;
410 simgrid::mc::Variable* var = info->find_variable(name);
415 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos) {
416 simgrid::mc::Variable* var = info->find_variable(name);
424 void RemoteClient::read_variable(const char* name, void* target, size_t size) const
426 simgrid::mc::Variable* var = this->find_variable(name);
427 xbt_assert(var->address, "No simple location for this variable");
428 xbt_assert(var->type->full_type, "Partial type for %s, cannot check size", name);
429 xbt_assert((size_t)var->type->full_type->byte_size == size, "Unexpected size for %s (expected %zu, was %zu)", name,
430 size, (size_t)var->type->full_type->byte_size);
431 this->read_bytes(target, size, remote(var->address));
434 std::string RemoteClient::read_string(RemotePtr<char> address) const
439 // TODO, use std::vector with .data() in C++17 to avoid useless copies
440 std::vector<char> res(128);
444 ssize_t c = pread(this->memory_file, res.data() + off, res.size() - off, (off_t)address.address() + off);
449 xbt_die("Could not read from from remote process");
452 xbt_die("Could not read string from remote process");
454 void* p = memchr(res.data() + off, '\0', c);
456 return std::string(res.data());
459 if (off == (off_t)res.size())
460 res.resize(res.size() * 2);
464 const void* RemoteClient::read_bytes(void* buffer, std::size_t size, RemotePtr<void> address, int process_index,
465 ReadOptions options) const
467 if (process_index != simgrid::mc::ProcessIndexDisabled) {
468 std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->find_object_info_rw((void*)address.address());
469 // Segment overlap is not handled.
471 if (info.get() && this->privatized(*info)) {
472 if (process_index < 0)
473 xbt_die("Missing process index");
474 if (process_index >= (int)MC_smpi_process_count())
475 xbt_die("Invalid process index");
477 // Read smpi_privatization_regions from MCed:
478 smpi_privatization_region_t remote_smpi_privatization_regions =
479 mc_model_checker->process().read_variable<smpi_privatization_region_t>("smpi_privatization_regions");
481 s_smpi_privatization_region_t privatization_region =
482 mc_model_checker->process().read<s_smpi_privatization_region_t>(
483 remote(remote_smpi_privatization_regions + process_index));
485 // Address translation in the privatization segment:
486 size_t offset = address.address() - (std::uint64_t)info->start_rw;
487 address = remote((char*)privatization_region.address + offset);
491 if (pread_whole(this->memory_file, buffer, size, (size_t)address.address()) < 0)
492 xbt_die("Read at %p from process %lli failed", (void*)address.address(), (long long)this->pid_);
496 /** Write data to a process memory
498 * @param buffer local memory address (source)
499 * @param len data size
500 * @param address target process memory address (target)
502 void RemoteClient::write_bytes(const void* buffer, size_t len, RemotePtr<void> address)
504 if (pwrite_whole(this->memory_file, buffer, len, (size_t)address.address()) < 0)
505 xbt_die("Write to process %lli failed", (long long)this->pid_);
508 void RemoteClient::clear_bytes(RemotePtr<void> address, size_t len)
510 pthread_once(&zero_buffer_flag, zero_buffer_init);
512 size_t s = len > zero_buffer_size ? zero_buffer_size : len;
513 this->write_bytes(zero_buffer, s, address);
514 address = remote((char*)address.address() + s);
519 void RemoteClient::ignore_region(std::uint64_t addr, std::size_t size)
521 IgnoredRegion region;
525 if (ignored_regions_.empty()) {
526 ignored_regions_.push_back(region);
530 unsigned int cursor = 0;
531 IgnoredRegion* current_region = nullptr;
534 int end = ignored_regions_.size() - 1;
535 while (start <= end) {
536 cursor = (start + end) / 2;
537 current_region = &ignored_regions_[cursor];
538 if (current_region->addr == addr) {
539 if (current_region->size == size)
541 else if (current_region->size < size)
545 } else if (current_region->addr < addr)
551 std::size_t position;
552 if (current_region->addr == addr) {
553 if (current_region->size < size)
554 position = cursor + 1;
557 } else if (current_region->addr < addr)
558 position = cursor + 1;
561 ignored_regions_.insert(ignored_regions_.begin() + position, region);
564 void RemoteClient::ignore_heap(IgnoredHeapRegion const& region)
566 if (ignored_heap_.empty()) {
567 ignored_heap_.push_back(std::move(region));
571 typedef std::vector<IgnoredHeapRegion>::size_type size_type;
574 size_type end = ignored_heap_.size() - 1;
576 // Binary search the position of insertion:
578 while (start <= end) {
579 cursor = start + (end - start) / 2;
580 auto& current_region = ignored_heap_[cursor];
581 if (current_region.address == region.address)
583 else if (current_region.address < region.address)
585 else if (cursor != 0)
592 // Insert it mc_heap_ignore_region_t:
593 if (ignored_heap_[cursor].address < region.address)
595 ignored_heap_.insert(ignored_heap_.begin() + cursor, region);
598 void RemoteClient::unignore_heap(void* address, size_t size)
600 typedef std::vector<IgnoredHeapRegion>::size_type size_type;
603 size_type end = ignored_heap_.size() - 1;
607 while (start <= end) {
608 cursor = (start + end) / 2;
609 auto& region = ignored_heap_[cursor];
610 if (region.address == address) {
611 ignored_heap_.erase(ignored_heap_.begin() + cursor);
613 } else if (region.address < address)
615 else if ((char*)region.address <= ((char*)address + size)) {
616 ignored_heap_.erase(ignored_heap_.begin() + cursor);
618 } else if (cursor != 0)
626 void RemoteClient::ignore_local_variable(const char* var_name, const char* frame_name)
628 if (frame_name != nullptr && strcmp(frame_name, "*") == 0)
629 frame_name = nullptr;
630 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos)
631 info->remove_local_variable(var_name, frame_name);
634 std::vector<simgrid::mc::ActorInformation>& RemoteClient::actors()
636 this->refresh_simix();
637 return smx_actors_infos;
640 std::vector<simgrid::mc::ActorInformation>& RemoteClient::dead_actors()
642 this->refresh_simix();
643 return smx_dead_actors_infos;
646 void RemoteClient::dumpStack()
648 unw_addr_space_t as = unw_create_addr_space(&_UPT_accessors, BYTE_ORDER);
650 XBT_ERROR("Could not initialize ptrace address space");
654 void* context = _UPT_create(this->pid_);
655 if (context == nullptr) {
656 unw_destroy_addr_space(as);
657 XBT_ERROR("Could not initialize ptrace context");
662 if (unw_init_remote(&cursor, as, context) != 0) {
663 _UPT_destroy(context);
664 unw_destroy_addr_space(as);
665 XBT_ERROR("Could not initialiez ptrace cursor");
669 simgrid::mc::dumpStack(stderr, cursor);
671 _UPT_destroy(context);
672 unw_destroy_addr_space(as);
676 bool RemoteClient::actor_is_enabled(aid_t pid)
678 s_mc_message_actor_enabled msg{MC_MESSAGE_ACTOR_ENABLED, pid};
679 process()->getChannel().send(msg);
680 char buff[MC_MESSAGE_LENGTH];
681 ssize_t received = process()->getChannel().receive(buff, MC_MESSAGE_LENGTH, true);
682 xbt_assert(received == sizeof(s_mc_message_int), "Unexpected size in answer to ACTOR_ENABLED");
683 return ((mc_message_int_t*)buff)->value;