1 /* Copyright (c) 2014-2015. The SimGrid Team.
2 * All rights reserved. */
4 /* This program is free software; you can redistribute it and/or modify it
5 * under the terms of the license (GNU LGPL) which comes with this package. */
7 #define _FILE_OFFSET_BITS 64
14 #include <sys/ptrace.h>
18 #include <sys/types.h>
22 #include <sys/mman.h> // PROT_*
28 #include <libunwind.h>
29 #include <libunwind-ptrace.h>
33 #include <xbt/mmalloc.h>
35 #include "src/mc/mc_unw.h"
36 #include "src/mc/mc_snapshot.h"
37 #include "src/mc/mc_ignore.h"
38 #include "src/mc/mc_smx.h"
40 #include "src/mc/Process.hpp"
41 #include "src/mc/AddressSpace.hpp"
42 #include "src/mc/ObjectInformation.hpp"
43 #include "src/mc/Variable.hpp"
45 using simgrid::mc::remote;
47 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_process, mc,
48 "MC process information");
55 #define SO_RE "\\.so[\\.0-9]*$"
56 #define VERSION_RE "-[\\.0-9-]*$"
58 // In lexicographic order (but this is currently not used in the code):
59 static const char *const filtered_libraries[] = {
88 static bool is_simgrid_lib(const char* libname)
90 return !strcmp(libname, "libsimgrid");
93 static bool is_filtered_lib(const char* libname)
95 for (const char* filtered_lib : filtered_libraries)
96 if (strcmp(libname, filtered_lib)==0)
101 struct s_mc_memory_map_re {
106 static char* get_lib_name(const char* pathname, struct s_mc_memory_map_re* res)
108 char* map_basename = xbt_basename(pathname);
111 if(regexec(&res->so_re, map_basename, 1, &match, 0)) {
116 char* libname = strndup(map_basename, match.rm_so);
118 map_basename = nullptr;
120 // Strip the version suffix:
121 if(libname && !regexec(&res->version_re, libname, 1, &match, 0)) {
122 char* temp = libname;
123 libname = strndup(temp, match.rm_so);
130 static ssize_t pread_whole(int fd, void *buf, size_t count, std::uint64_t offset)
132 char* buffer = (char*) buf;
133 ssize_t real_count = count;
135 ssize_t res = pread(fd, buffer, count, (std::int64_t) offset);
142 else if (errno != EINTR) {
143 perror("pread_whole");
150 static ssize_t pwrite_whole(int fd, const void *buf, size_t count, off_t offset)
152 const char* buffer = (const char*) buf;
153 ssize_t real_count = count;
155 ssize_t res = pwrite(fd, buffer, count, offset);
162 else if (errno != EINTR)
168 static pthread_once_t zero_buffer_flag = PTHREAD_ONCE_INIT;
169 static const void* zero_buffer;
170 static const size_t zero_buffer_size = 10 * 4096;
172 static void zero_buffer_init(void)
174 int fd = open("/dev/zero", O_RDONLY);
176 xbt_die("Could not open /dev/zero");
177 zero_buffer = mmap(nullptr, zero_buffer_size, PROT_READ, MAP_SHARED, fd, 0);
178 if (zero_buffer == MAP_FAILED)
179 xbt_die("Could not map the zero buffer");
183 int open_vm(pid_t pid, int flags)
185 const size_t buffer_size = 30;
186 char buffer[buffer_size];
187 int res = snprintf(buffer, buffer_size, "/proc/%lli/mem", (long long) pid);
188 if (res < 0 || (size_t) res >= buffer_size) {
189 errno = ENAMETOOLONG;
192 return open(buffer, flags);
197 Process::Process(pid_t pid, int sockfd) :
198 AddressSpace(this), pid_(pid), channel_(sockfd), running_(true)
203 this->memory_map_ = simgrid::xbt::get_memory_map(this->pid_);
204 this->init_memory_map_info();
206 int fd = open_vm(this->pid_, O_RDWR);
208 xbt_die("Could not open file for process virtual address space");
209 this->memory_file = fd;
211 // Read std_heap (is a struct mdesc*):
212 simgrid::mc::Variable* std_heap_var = this->find_variable("__mmalloc_default_mdp");
214 xbt_die("No heap information in the target process");
215 if(!std_heap_var->address)
216 xbt_die("No constant address for this variable");
217 this->read_bytes(&this->heap_address, sizeof(struct mdesc*),
218 remote(std_heap_var->address),
219 simgrid::mc::ProcessIndexDisabled);
221 this->smx_process_infos.clear();
222 this->smx_old_process_infos.clear();
223 this->unw_addr_space = simgrid::mc::UnwindContext::createUnwindAddressSpace();
224 this->unw_underlying_addr_space = simgrid::unw::create_addr_space();
225 this->unw_underlying_context = simgrid::unw::create_context(
226 this->unw_underlying_addr_space, this->pid_);
231 if (this->memory_file >= 0)
232 close(this->memory_file);
234 if (this->unw_underlying_addr_space != unw_local_addr_space) {
235 unw_destroy_addr_space(this->unw_underlying_addr_space);
236 _UPT_destroy(this->unw_underlying_context);
239 unw_destroy_addr_space(this->unw_addr_space);
242 /** Refresh the information about the process
244 * Do not use directly, this is used by the getters when appropriate
245 * in order to have fresh data.
247 void Process::refresh_heap()
249 // Read/dereference/refresh the std_heap pointer:
251 this->heap = std::unique_ptr<s_xbt_mheap_t>(new s_xbt_mheap_t());
252 this->read_bytes(this->heap.get(), sizeof(struct mdesc),
253 remote(this->heap_address), simgrid::mc::ProcessIndexDisabled);
254 this->cache_flags_ |= Process::cache_heap;
257 /** Refresh the information about the process
259 * Do not use direclty, this is used by the getters when appropriate
260 * in order to have fresh data.
262 void Process::refresh_malloc_info()
264 // Refresh process->heapinfo:
265 if (this->cache_flags_ & Process::cache_malloc)
267 size_t count = this->heap->heaplimit + 1;
268 if (this->heap_info.size() < count)
269 this->heap_info.resize(count);
270 this->read_bytes(this->heap_info.data(), count * sizeof(malloc_info),
271 remote(this->heap->heapinfo), simgrid::mc::ProcessIndexDisabled);
272 this->cache_flags_ |= Process::cache_malloc;
275 /** @brief Finds the range of the different memory segments and binary paths */
276 void Process::init_memory_map_info()
278 XBT_DEBUG("Get debug information ...");
279 this->maestro_stack_start_ = nullptr;
280 this->maestro_stack_end_ = nullptr;
281 this->object_infos.resize(0);
282 this->binary_info = nullptr;
283 this->libsimgrid_info = nullptr;
285 struct s_mc_memory_map_re res;
287 if(regcomp(&res.so_re, SO_RE, 0) || regcomp(&res.version_re, VERSION_RE, 0))
288 xbt_die(".so regexp did not compile");
290 std::vector<simgrid::xbt::VmMap> const& maps = this->memory_map_;
292 const char* current_name = nullptr;
294 this->object_infos.clear();
296 for (size_t i=0; i < maps.size(); i++) {
297 simgrid::xbt::VmMap const& reg = maps[i];
298 const char* pathname = maps[i].pathname.c_str();
301 if (maps[i].pathname.empty()) {
302 current_name = nullptr;
306 // [stack], [vvar], [vsyscall], [vdso] ...
307 if (pathname[0] == '[') {
308 if ((reg.prot & PROT_WRITE) && !memcmp(pathname, "[stack]", 7)) {
309 this->maestro_stack_start_ = remote(reg.start_addr);
310 this->maestro_stack_end_ = remote(reg.end_addr);
312 current_name = nullptr;
316 if (current_name && strcmp(current_name, pathname)==0)
319 current_name = pathname;
320 if (!(reg.prot & PROT_READ) && (reg.prot & PROT_EXEC))
323 const bool is_executable = !i;
324 char* libname = nullptr;
325 if (!is_executable) {
326 libname = get_lib_name(pathname, &res);
329 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 (libname && is_simgrid_lib(libname))
341 this->libsimgrid_info = info;
346 regfree(&res.version_re);
348 // Resolve time (including across different objects):
349 for (auto const& object_info : this->object_infos)
350 postProcessObjectInformation(this, object_info.get());
352 xbt_assert(this->maestro_stack_start_, "Did not find maestro_stack_start");
353 xbt_assert(this->maestro_stack_end_, "Did not find maestro_stack_end");
355 XBT_DEBUG("Get debug information done !");
358 std::shared_ptr<simgrid::mc::ObjectInformation> Process::find_object_info(RemotePtr<void> addr) const
360 for (auto const& object_info : this->object_infos)
361 if (addr.address() >= (std::uint64_t)object_info->start
362 && addr.address() <= (std::uint64_t)object_info->end)
367 std::shared_ptr<ObjectInformation> Process::find_object_info_exec(RemotePtr<void> addr) const
369 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
370 if (addr.address() >= (std::uint64_t) info->start_exec
371 && addr.address() <= (std::uint64_t) info->end_exec)
376 std::shared_ptr<ObjectInformation> Process::find_object_info_rw(RemotePtr<void> addr) const
378 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
379 if (addr.address() >= (std::uint64_t)info->start_rw
380 && addr.address() <= (std::uint64_t)info->end_rw)
385 simgrid::mc::Frame* Process::find_function(RemotePtr<void> ip) const
387 std::shared_ptr<simgrid::mc::ObjectInformation> info = this->find_object_info_exec(ip);
388 return info ? info->find_function((void*) ip.address()) : nullptr;
391 /** Find (one occurrence of) the named variable definition
393 simgrid::mc::Variable* Process::find_variable(const char* name) const
395 // First lookup the variable in the executable shared object.
396 // A global variable used directly by the executable code from a library
397 // is reinstanciated in the executable memory .data/.bss.
398 // We need to look up the variable in the executable first.
399 if (this->binary_info) {
400 std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->binary_info;
401 simgrid::mc::Variable* var = info->find_variable(name);
406 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos) {
407 simgrid::mc::Variable* var = info->find_variable(name);
415 void Process::read_variable(const char* name, void* target, size_t size) const
417 simgrid::mc::Variable* var = this->find_variable(name);
419 xbt_die("No simple location for this variable");
420 if (!var->type->full_type)
421 xbt_die("Partial type for %s, cannot check size", name);
422 if ((size_t) var->type->full_type->byte_size != size)
423 xbt_die("Unexpected size for %s (expected %zi, was %zi)",
424 name, size, (size_t) var->type->full_type->byte_size);
425 this->read_bytes(target, size, remote(var->address));
428 std::string Process::read_string(RemotePtr<char> address) const
433 // TODO, use std::vector with .data() in C++17 to avoid useless copies
434 std::vector<char> res(128);
438 ssize_t c = pread(this->memory_file, res.data() + off, res.size() - off, (off_t) address.address() + off);
443 xbt_die("Could not read from from remote process");
446 xbt_die("Could not read string from remote process");
448 void* p = memchr(res.data() + off, '\0', c);
450 return std::string(res.data());
453 if (off == (off_t) res.size())
454 res.resize(res.size() * 2);
458 const void *Process::read_bytes(void* buffer, std::size_t size,
459 RemotePtr<void> address, int process_index,
460 ReadOptions options) const
462 if (process_index != simgrid::mc::ProcessIndexDisabled) {
463 std::shared_ptr<simgrid::mc::ObjectInformation> const& info =
464 this->find_object_info_rw((void*)address.address());
465 // Segment overlap is not handled.
467 if (info.get() && this->privatized(*info)) {
468 if (process_index < 0)
469 xbt_die("Missing process index");
470 if (process_index >= (int) MC_smpi_process_count())
471 xbt_die("Invalid process index");
473 // Read smpi_privatisation_regions from MCed:
474 smpi_privatisation_region_t remote_smpi_privatisation_regions =
475 mc_model_checker->process().read_variable<smpi_privatisation_region_t>(
476 "smpi_privatisation_regions");
478 s_smpi_privatisation_region_t privatisation_region =
479 mc_model_checker->process().read<s_smpi_privatisation_region_t>(
480 remote(remote_smpi_privatisation_regions + process_index));
482 // Address translation in the privatization segment:
483 size_t offset = address.address() - (std::uint64_t)info->start_rw;
484 address = remote((char*)privatisation_region.address + offset);
489 if (pread_whole(this->memory_file, buffer, size, address.address()) < 0)
490 xbt_die("Read from process %lli failed", (long long) this->pid_);
494 /** Write data to a process memory
496 * @param process the process
497 * @param local local memory address (source)
498 * @param remote target process memory address (target)
499 * @param len data size
501 void Process::write_bytes(const void* buffer, size_t len, RemotePtr<void> address)
503 if (pwrite_whole(this->memory_file, buffer, len, address.address()) < 0)
504 xbt_die("Write to process %lli failed", (long long) this->pid_);
507 void Process::clear_bytes(RemotePtr<void> address, size_t len)
509 pthread_once(&zero_buffer_flag, zero_buffer_init);
511 size_t s = len > zero_buffer_size ? zero_buffer_size : len;
512 this->write_bytes(zero_buffer, s, address);
513 address = remote((char*) address.address() + s);
518 void Process::ignore_region(std::uint64_t addr, std::size_t size)
520 IgnoredRegion region;
524 if (ignored_regions_.empty()) {
525 ignored_regions_.push_back(region);
529 unsigned int cursor = 0;
530 IgnoredRegion* current_region = nullptr;
533 int end = ignored_regions_.size() - 1;
534 while (start <= end) {
535 cursor = (start + end) / 2;
536 current_region = &ignored_regions_[cursor];
537 if (current_region->addr == addr) {
538 if (current_region->size == size)
540 else if (current_region->size < size)
544 } else if (current_region->addr < addr)
550 std::size_t position;
551 if (current_region->addr == addr) {
552 if (current_region->size < size)
553 position = cursor + 1;
556 } else if (current_region->addr < addr)
557 position = cursor + 1;
560 ignored_regions_.insert(
561 ignored_regions_.begin() + position, region);
564 void Process::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 Process::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 Process::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 :
632 info->remove_local_variable(var_name, frame_name);
635 std::vector<simgrid::mc::SimixProcessInformation>& Process::simix_processes()
637 this->refresh_simix();
638 return smx_process_infos;
641 std::vector<simgrid::mc::SimixProcessInformation>& Process::old_simix_processes()
643 this->refresh_simix();
644 return smx_old_process_infos;
647 void Process::dumpStack()
649 unw_addr_space_t as = unw_create_addr_space(&_UPT_accessors, __BYTE_ORDER);
651 XBT_ERROR("Could not initialize ptrace address space");
655 void* context = _UPT_create(this->pid_);
656 if (context == nullptr) {
657 unw_destroy_addr_space(as);
658 XBT_ERROR("Could not initialize ptrace context");
663 if (unw_init_remote(&cursor, as, context) != 0) {
664 _UPT_destroy(context);
665 unw_destroy_addr_space(as);
666 XBT_ERROR("Could not initialiez ptrace cursor");
670 simgrid::mc::dumpStack(stderr, cursor);
672 _UPT_destroy(context);
673 unw_destroy_addr_space(as);