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[] = {
89 static bool is_simgrid_lib(const char* libname)
91 return !strcmp(libname, "libsimgrid");
94 static bool is_filtered_lib(const char* libname)
96 for (const char* filtered_lib : filtered_libraries)
97 if (strcmp(libname, filtered_lib)==0)
102 struct s_mc_memory_map_re {
107 static char* get_lib_name(const char* pathname, struct s_mc_memory_map_re* res)
109 char* map_basename = xbt_basename(pathname);
112 if(regexec(&res->so_re, map_basename, 1, &match, 0)) {
117 char* libname = strndup(map_basename, match.rm_so);
119 map_basename = nullptr;
121 // Strip the version suffix:
122 if(libname && !regexec(&res->version_re, libname, 1, &match, 0)) {
123 char* temp = libname;
124 libname = strndup(temp, match.rm_so);
131 static ssize_t pread_whole(int fd, void *buf, size_t count, std::uint64_t offset)
133 char* buffer = (char*) buf;
134 ssize_t real_count = count;
136 ssize_t res = pread(fd, buffer, count, (std::int64_t) offset);
143 else if (errno != EINTR) {
144 perror("pread_whole");
151 static ssize_t pwrite_whole(int fd, const void *buf, size_t count, off_t offset)
153 const char* buffer = (const char*) buf;
154 ssize_t real_count = count;
156 ssize_t res = pwrite(fd, buffer, count, offset);
163 else if (errno != EINTR)
169 static pthread_once_t zero_buffer_flag = PTHREAD_ONCE_INIT;
170 static const void* zero_buffer;
171 static const size_t zero_buffer_size = 10 * 4096;
173 static void zero_buffer_init(void)
175 int fd = open("/dev/zero", O_RDONLY);
177 xbt_die("Could not open /dev/zero");
178 zero_buffer = mmap(nullptr, zero_buffer_size, PROT_READ, MAP_SHARED, fd, 0);
179 if (zero_buffer == MAP_FAILED)
180 xbt_die("Could not map the zero buffer");
185 int open_process_file(pid_t pid, const char* file, int flags)
188 snprintf(buff, sizeof(buff), "/proc/%li/%s", (long) pid, file);
189 return open(buff, flags);
192 int open_vm(pid_t pid, int flags)
194 const size_t buffer_size = 30;
195 char buffer[buffer_size];
196 int res = snprintf(buffer, buffer_size, "/proc/%lli/mem", (long long) pid);
197 if (res < 0 || (size_t) res >= buffer_size) {
198 errno = ENAMETOOLONG;
201 return open(buffer, flags);
206 Process::Process(pid_t pid, int sockfd) :
207 AddressSpace(this), pid_(pid), channel_(sockfd), running_(true)
212 this->memory_map_ = simgrid::xbt::get_memory_map(this->pid_);
213 this->init_memory_map_info();
215 int fd = open_vm(this->pid_, O_RDWR);
217 xbt_die("Could not open file for process virtual address space");
218 this->memory_file = fd;
220 // Read std_heap (is a struct mdesc*):
221 simgrid::mc::Variable* std_heap_var = this->find_variable("__mmalloc_default_mdp");
223 xbt_die("No heap information in the target process");
224 if(!std_heap_var->address)
225 xbt_die("No constant address for this variable");
226 this->read_bytes(&this->heap_address, sizeof(struct mdesc*),
227 remote(std_heap_var->address),
228 simgrid::mc::ProcessIndexDisabled);
230 this->smx_process_infos.clear();
231 this->smx_old_process_infos.clear();
232 this->unw_addr_space = simgrid::mc::UnwindContext::createUnwindAddressSpace();
233 this->unw_underlying_addr_space = simgrid::unw::create_addr_space();
234 this->unw_underlying_context = simgrid::unw::create_context(
235 this->unw_underlying_addr_space, this->pid_);
240 if (this->memory_file >= 0)
241 close(this->memory_file);
243 if (this->unw_underlying_addr_space != unw_local_addr_space) {
244 unw_destroy_addr_space(this->unw_underlying_addr_space);
245 _UPT_destroy(this->unw_underlying_context);
248 unw_destroy_addr_space(this->unw_addr_space);
250 if (this->clear_refs_fd_ >= 0)
251 close(this->clear_refs_fd_);
252 if (this->pagemap_fd_ >= 0)
253 close(this->pagemap_fd_);
256 /** Refresh the information about the process
258 * Do not use direclty, this is used by the getters when appropriate
259 * in order to have fresh data.
261 void Process::refresh_heap()
263 // Read/dereference/refresh the std_heap pointer:
265 this->heap = std::unique_ptr<s_xbt_mheap_t>(new s_xbt_mheap_t());
266 this->read_bytes(this->heap.get(), sizeof(struct mdesc),
267 remote(this->heap_address), simgrid::mc::ProcessIndexDisabled);
268 this->cache_flags_ |= Process::cache_heap;
271 /** Refresh the information about the process
273 * Do not use direclty, this is used by the getters when appropriate
274 * in order to have fresh data.
276 void Process::refresh_malloc_info()
278 // Refresh process->heapinfo:
279 if (this->cache_flags_ & Process::cache_malloc)
281 size_t count = this->heap->heaplimit + 1;
282 if (this->heap_info.size() < count)
283 this->heap_info.resize(count);
284 this->read_bytes(this->heap_info.data(), count * sizeof(malloc_info),
285 remote(this->heap->heapinfo), simgrid::mc::ProcessIndexDisabled);
286 this->cache_flags_ |= Process::cache_malloc;
289 /** @brief Finds the range of the different memory segments and binary paths */
290 void Process::init_memory_map_info()
292 XBT_DEBUG("Get debug information ...");
293 this->maestro_stack_start_ = nullptr;
294 this->maestro_stack_end_ = nullptr;
295 this->object_infos.resize(0);
296 this->binary_info = nullptr;
297 this->libsimgrid_info = nullptr;
299 struct s_mc_memory_map_re res;
301 if(regcomp(&res.so_re, SO_RE, 0) || regcomp(&res.version_re, VERSION_RE, 0))
302 xbt_die(".so regexp did not compile");
304 std::vector<simgrid::xbt::VmMap> const& maps = this->memory_map_;
306 const char* current_name = nullptr;
308 this->object_infos.clear();
310 for (size_t i=0; i < maps.size(); i++) {
311 simgrid::xbt::VmMap const& reg = maps[i];
312 const char* pathname = maps[i].pathname.c_str();
315 if (maps[i].pathname.empty()) {
316 current_name = nullptr;
320 // [stack], [vvar], [vsyscall], [vdso] ...
321 if (pathname[0] == '[') {
322 if ((reg.prot & PROT_WRITE) && !memcmp(pathname, "[stack]", 7)) {
323 this->maestro_stack_start_ = remote(reg.start_addr);
324 this->maestro_stack_end_ = remote(reg.end_addr);
326 current_name = nullptr;
330 if (current_name && strcmp(current_name, pathname)==0)
333 current_name = pathname;
334 if (!(reg.prot & PROT_READ) && (reg.prot & PROT_EXEC))
337 const bool is_executable = !i;
338 char* libname = nullptr;
339 if (!is_executable) {
340 libname = get_lib_name(pathname, &res);
343 if (is_filtered_lib(libname)) {
349 std::shared_ptr<simgrid::mc::ObjectInformation> info =
350 simgrid::mc::createObjectInformation(this->memory_map_, pathname);
351 this->object_infos.push_back(info);
353 this->binary_info = info;
354 else if (libname && is_simgrid_lib(libname))
355 this->libsimgrid_info = info;
360 regfree(&res.version_re);
362 // Resolve time (including accross differents objects):
363 for (auto const& object_info : this->object_infos)
364 postProcessObjectInformation(this, object_info.get());
366 xbt_assert(this->maestro_stack_start_, "Did not find maestro_stack_start");
367 xbt_assert(this->maestro_stack_end_, "Did not find maestro_stack_end");
369 XBT_DEBUG("Get debug information done !");
372 std::shared_ptr<simgrid::mc::ObjectInformation> Process::find_object_info(RemotePtr<void> addr) const
374 for (auto const& object_info : this->object_infos)
375 if (addr.address() >= (std::uint64_t)object_info->start
376 && addr.address() <= (std::uint64_t)object_info->end)
381 std::shared_ptr<ObjectInformation> Process::find_object_info_exec(RemotePtr<void> addr) const
383 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
384 if (addr.address() >= (std::uint64_t) info->start_exec
385 && addr.address() <= (std::uint64_t) info->end_exec)
390 std::shared_ptr<ObjectInformation> Process::find_object_info_rw(RemotePtr<void> addr) const
392 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos)
393 if (addr.address() >= (std::uint64_t)info->start_rw
394 && addr.address() <= (std::uint64_t)info->end_rw)
399 simgrid::mc::Frame* Process::find_function(RemotePtr<void> ip) const
401 std::shared_ptr<simgrid::mc::ObjectInformation> info = this->find_object_info_exec(ip);
402 return info ? info->find_function((void*) ip.address()) : nullptr;
405 /** Find (one occurence of) the named variable definition
407 simgrid::mc::Variable* Process::find_variable(const char* name) const
409 // First lookup the variable in the executable shared object.
410 // A global variable used directly by the executable code from a library
411 // is reinstanciated in the executable memory .data/.bss.
412 // We need to look up the variable in the execvutable first.
413 if (this->binary_info) {
414 std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->binary_info;
415 simgrid::mc::Variable* var = info->find_variable(name);
420 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos) {
421 simgrid::mc::Variable* var = info->find_variable(name);
429 void Process::read_variable(const char* name, void* target, size_t size) const
431 simgrid::mc::Variable* var = this->find_variable(name);
433 xbt_die("No simple location for this variable");
434 if (!var->type->full_type)
435 xbt_die("Partial type for %s, cannot check size", name);
436 if ((size_t) var->type->full_type->byte_size != size)
437 xbt_die("Unexpected size for %s (expected %zi, was %zi)",
438 name, size, (size_t) var->type->full_type->byte_size);
439 this->read_bytes(target, size, remote(var->address));
442 std::string Process::read_string(RemotePtr<void> address) const
447 std::vector<char> res(128);
451 ssize_t c = pread(this->memory_file, res.data() + off, res.size() - off, (off_t) address.address() + off);
456 xbt_die("Could not read from from remote process");
459 xbt_die("Could not read string from remote process");
461 void* p = memchr(res.data() + off, '\0', c);
463 return std::string(res.data());
466 if (off == (off_t) res.size())
467 res.resize(res.size() * 2);
471 const void *Process::read_bytes(void* buffer, std::size_t size,
472 RemotePtr<void> address, int process_index,
473 ReadOptions options) const
475 if (process_index != simgrid::mc::ProcessIndexDisabled) {
476 std::shared_ptr<simgrid::mc::ObjectInformation> const& info =
477 this->find_object_info_rw((void*)address.address());
478 // Segment overlap is not handled.
480 if (info.get() && this->privatized(*info)) {
481 if (process_index < 0)
482 xbt_die("Missing process index");
483 if (process_index >= (int) MC_smpi_process_count())
484 xbt_die("Invalid process index");
486 // Read smpi_privatisation_regions from MCed:
487 smpi_privatisation_region_t remote_smpi_privatisation_regions =
488 mc_model_checker->process().read_variable<smpi_privatisation_region_t>(
489 "smpi_privatisation_regions");
491 s_smpi_privatisation_region_t privatisation_region =
492 mc_model_checker->process().read<s_smpi_privatisation_region_t>(
493 remote(remote_smpi_privatisation_regions + process_index));
495 // Address translation in the privaization segment:
496 size_t offset = address.address() - (std::uint64_t)info->start_rw;
497 address = remote((char*)privatisation_region.address + offset);
502 if (pread_whole(this->memory_file, buffer, size, address.address()) < 0)
503 xbt_die("Read from process %lli failed", (long long) this->pid_);
507 /** Write data to a process memory
509 * @param process the process
510 * @param local local memory address (source)
511 * @param remote target process memory address (target)
512 * @param len data size
514 void Process::write_bytes(const void* buffer, size_t len, RemotePtr<void> address)
516 if (pwrite_whole(this->memory_file, buffer, len, address.address()) < 0)
517 xbt_die("Write to process %lli failed", (long long) this->pid_);
520 void Process::clear_bytes(RemotePtr<void> address, size_t len)
522 pthread_once(&zero_buffer_flag, zero_buffer_init);
524 size_t s = len > zero_buffer_size ? zero_buffer_size : len;
525 this->write_bytes(zero_buffer, s, address);
526 address = remote((char*) address.address() + s);
531 void Process::ignore_region(std::uint64_t addr, std::size_t size)
533 IgnoredRegion region;
537 if (ignored_regions_.empty()) {
538 ignored_regions_.push_back(region);
542 unsigned int cursor = 0;
543 IgnoredRegion* current_region = nullptr;
546 int end = ignored_regions_.size() - 1;
547 while (start <= end) {
548 cursor = (start + end) / 2;
549 current_region = &ignored_regions_[cursor];
550 if (current_region->addr == addr) {
551 if (current_region->size == size)
553 else if (current_region->size < size)
557 } else if (current_region->addr < addr)
563 std::size_t position;
564 if (current_region->addr == addr) {
565 if (current_region->size < size)
566 position = cursor + 1;
569 } else if (current_region->addr < addr)
570 position = cursor + 1;
573 ignored_regions_.insert(
574 ignored_regions_.begin() + position, region);
577 void Process::reset_soft_dirty()
579 if (this->clear_refs_fd_ < 0) {
580 this->clear_refs_fd_ = open_process_file(pid_, "clear_refs", O_WRONLY|O_CLOEXEC);
581 if (this->clear_refs_fd_ < 0)
582 xbt_die("Could not open clear_refs file for soft-dirty tracking. Run as root?");
584 if(::write(this->clear_refs_fd_, "4\n", 2) != 2)
585 xbt_die("Could not reset softdirty bits");
588 void Process::read_pagemap(uint64_t* pagemap, size_t page_start, size_t page_count)
590 if (pagemap_fd_ < 0) {
591 pagemap_fd_ = open_process_file(pid_, "pagemap", O_RDONLY|O_CLOEXEC);
593 xbt_die("Could not open pagemap file for soft-dirty tracking. Run as root?");
595 ssize_t bytesize = sizeof(uint64_t) * page_count;
596 off_t offset = sizeof(uint64_t) * page_start;
597 if (pread_whole(pagemap_fd_, pagemap, bytesize, offset) != bytesize)
598 xbt_die("Could not read pagemap");
601 void Process::ignore_heap(IgnoredHeapRegion const& region)
603 if (ignored_heap_.empty()) {
604 ignored_heap_.push_back(std::move(region));
608 typedef std::vector<IgnoredHeapRegion>::size_type size_type;
611 size_type end = ignored_heap_.size() - 1;
613 // Binary search the position of insertion:
615 while (start <= end) {
616 cursor = start + (end - start) / 2;
617 auto& current_region = ignored_heap_[cursor];
618 if (current_region.address == region.address)
620 else if (current_region.address < region.address)
622 else if (cursor != 0)
629 // Insert it mc_heap_ignore_region_t:
630 if (ignored_heap_[cursor].address < region.address)
632 ignored_heap_.insert( ignored_heap_.begin() + cursor, region);
635 void Process::unignore_heap(void *address, size_t size)
637 typedef std::vector<IgnoredHeapRegion>::size_type size_type;
640 size_type end = ignored_heap_.size() - 1;
644 while (start <= end) {
645 cursor = (start + end) / 2;
646 auto& region = ignored_heap_[cursor];
647 if (region.address == address) {
648 ignored_heap_.erase(ignored_heap_.begin() + cursor);
650 } else if (region.address < address)
652 else if ((char *) region.address <= ((char *) address + size)) {
653 ignored_heap_.erase(ignored_heap_.begin() + cursor);
655 } else if (cursor != 0)
663 void Process::ignore_local_variable(const char *var_name, const char *frame_name)
665 if (frame_name != nullptr && strcmp(frame_name, "*") == 0)
666 frame_name = nullptr;
667 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info :
669 info->remove_local_variable(var_name, frame_name);
672 std::vector<simgrid::mc::SimixProcessInformation>& Process::simix_processes()
674 this->refresh_simix();
675 return smx_process_infos;
678 std::vector<simgrid::mc::SimixProcessInformation>& Process::old_simix_processes()
680 this->refresh_simix();
681 return smx_old_process_infos;
684 void Process::dumpStack()
686 unw_addr_space_t as = unw_create_addr_space(&_UPT_accessors, __BYTE_ORDER);
688 XBT_ERROR("Could not initialize ptrace address space");
692 void* context = _UPT_create(this->pid_);
693 if (context == nullptr) {
694 unw_destroy_addr_space(as);
695 XBT_ERROR("Could not initialize ptrace context");
700 if (unw_init_remote(&cursor, as, context) != 0) {
701 _UPT_destroy(context);
702 unw_destroy_addr_space(as);
703 XBT_ERROR("Could not initialiez ptrace cursor");
707 simgrid::mc::dumpStack(stderr, cursor);
709 _UPT_destroy(context);
710 unw_destroy_addr_space(as);