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
15 #include <sys/types.h>
19 #include <sys/mman.h> // PROT_*
25 #include <libunwind.h>
26 #include <libunwind-ptrace.h>
28 #include <xbt/mmalloc.h>
30 #include "src/mc/mc_object_info.h"
31 #include "src/mc/mc_unw.h"
32 #include "src/mc/mc_snapshot.h"
33 #include "src/mc/mc_ignore.h"
34 #include "src/mc/mc_smx.h"
36 #include "src/mc/Process.hpp"
37 #include "src/mc/AddressSpace.hpp"
38 #include "src/mc/ObjectInformation.hpp"
39 #include "src/mc/Variable.hpp"
41 using simgrid::mc::remote;
45 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_process, mc,
46 "MC process information");
50 #define SO_RE "\\.so[\\.0-9]*$"
51 #define VERSION_RE "-[\\.0-9-]*$"
53 static const char *const FILTERED_LIBS[] = {
83 static bool MC_is_simgrid_lib(const char* libname)
85 return !strcmp(libname, "libsimgrid");
88 static bool MC_is_filtered_lib(const char* libname)
90 for (const char* filtered_lib : FILTERED_LIBS)
91 if (strcmp(libname, filtered_lib)==0)
96 struct s_mc_memory_map_re {
101 static char* MC_get_lib_name(const char* pathname, struct s_mc_memory_map_re* res)
103 const char* map_basename = basename((char*) pathname);
106 if(regexec(&res->so_re, map_basename, 1, &match, 0))
109 char* libname = strndup(map_basename, match.rm_so);
111 // Strip the version suffix:
112 if(libname && !regexec(&res->version_re, libname, 1, &match, 0)) {
113 char* temp = libname;
114 libname = strndup(temp, match.rm_so);
121 static ssize_t pread_whole(int fd, void *buf, size_t count, std::uint64_t offset)
123 char* buffer = (char*) buf;
124 ssize_t real_count = count;
126 ssize_t res = pread(fd, buffer, count, (std::int64_t) offset);
133 } else if (errno != EINTR) {
134 perror("pread_whole");
141 static ssize_t pwrite_whole(int fd, const void *buf, size_t count, off_t offset)
143 const char* buffer = (const char*) buf;
144 ssize_t real_count = count;
146 ssize_t res = pwrite(fd, buffer, count, offset);
153 } else if (errno != EINTR) {
160 static pthread_once_t zero_buffer_flag = PTHREAD_ONCE_INIT;
161 static const void* zero_buffer;
162 static const size_t zero_buffer_size = 10 * 4096;
164 static void MC_zero_buffer_init(void)
166 int fd = open("/dev/zero", O_RDONLY);
168 xbt_die("Could not open /dev/zero");
169 zero_buffer = mmap(NULL, zero_buffer_size, PROT_READ, MAP_SHARED, fd, 0);
170 if (zero_buffer == MAP_FAILED)
171 xbt_die("Could not map the zero buffer");
176 int open_process_file(pid_t pid, const char* file, int flags)
179 snprintf(buff, sizeof(buff), "/proc/%li/%s", (long) pid, file);
180 return open(buff, flags);
188 int open_vm(pid_t pid, int flags)
190 const size_t buffer_size = 30;
191 char buffer[buffer_size];
192 int res = snprintf(buffer, buffer_size, "/proc/%lli/mem", (long long) pid);
193 if (res < 0 || (size_t) res >= buffer_size) {
194 errno = ENAMETOOLONG;
197 return open(buffer, flags);
209 Process::Process(pid_t pid, int sockfd) : AddressSpace(this)
211 Process* process = this;
212 process->socket_ = sockfd;
214 process->running_ = true;
215 process->memory_map_ = simgrid::xbt::get_memory_map(pid);
216 process->cache_flags = MC_PROCESS_CACHE_FLAG_NONE;
217 process->init_memory_map_info();
218 process->clear_refs_fd_ = -1;
219 process->pagemap_fd_ = -1;
220 process->privatized_ = false;
222 int fd = open_vm(process->pid_, O_RDWR);
224 xbt_die("Could not open file for process virtual address space");
225 process->memory_file = fd;
227 // Read std_heap (is a struct mdesc*):
228 simgrid::mc::Variable* std_heap_var = process->find_variable("__mmalloc_default_mdp");
230 xbt_die("No heap information in the target process");
231 if(!std_heap_var->address)
232 xbt_die("No constant address for this variable");
233 process->read_bytes(&process->heap_address, sizeof(struct mdesc*),
234 remote(std_heap_var->address),
235 simgrid::mc::ProcessIndexDisabled);
237 process->smx_process_infos = MC_smx_process_info_list_new();
238 process->smx_old_process_infos = MC_smx_process_info_list_new();
239 process->unw_addr_space = unw_create_addr_space(&mc_unw_accessors , __BYTE_ORDER);
240 process->unw_underlying_addr_space = unw_create_addr_space(&mc_unw_vmread_accessors, __BYTE_ORDER);
241 process->unw_underlying_context = _UPT_create(pid);
246 Process* process = this;
248 if (this->socket_ >= 0 && close(this->socket_) < 0)
249 xbt_die("Could not close communication socket");
253 process->maestro_stack_start_ = nullptr;
254 process->maestro_stack_end_ = nullptr;
256 xbt_dynar_free(&process->smx_process_infos);
257 xbt_dynar_free(&process->smx_old_process_infos);
259 if (process->memory_file >= 0) {
260 close(process->memory_file);
263 if (process->unw_underlying_addr_space != unw_local_addr_space) {
264 unw_destroy_addr_space(process->unw_underlying_addr_space);
265 _UPT_destroy(process->unw_underlying_context);
267 process->unw_underlying_context = NULL;
268 process->unw_underlying_addr_space = NULL;
270 unw_destroy_addr_space(process->unw_addr_space);
271 process->unw_addr_space = NULL;
273 process->cache_flags = MC_PROCESS_CACHE_FLAG_NONE;
275 if (process->clear_refs_fd_ >= 0)
276 close(process->clear_refs_fd_);
277 if (process->pagemap_fd_ >= 0)
278 close(process->pagemap_fd_);
281 /** Refresh the information about the process
283 * Do not use direclty, this is used by the getters when appropriate
284 * in order to have fresh data.
286 void Process::refresh_heap()
288 xbt_assert(mc_mode == MC_MODE_SERVER);
289 // Read/dereference/refresh the std_heap pointer:
291 this->heap = std::unique_ptr<s_xbt_mheap_t>(new s_xbt_mheap_t());
292 this->read_bytes(this->heap.get(), sizeof(struct mdesc),
293 remote(this->heap_address), simgrid::mc::ProcessIndexDisabled);
294 this->cache_flags |= MC_PROCESS_CACHE_FLAG_HEAP;
297 /** Refresh the information about the process
299 * Do not use direclty, this is used by the getters when appropriate
300 * in order to have fresh data.
302 void Process::refresh_malloc_info()
304 xbt_assert(mc_mode == MC_MODE_SERVER);
305 if (!(this->cache_flags & MC_PROCESS_CACHE_FLAG_HEAP))
306 this->refresh_heap();
307 // Refresh process->heapinfo:
308 size_t count = this->heap->heaplimit + 1;
309 if (this->heap_info.size() < count)
310 this->heap_info.resize(count);
311 this->read_bytes(this->heap_info.data(), count * sizeof(malloc_info),
312 remote(this->heap->heapinfo), simgrid::mc::ProcessIndexDisabled);
313 this->cache_flags |= MC_PROCESS_CACHE_FLAG_MALLOC_INFO;
316 /** @brief Finds the range of the different memory segments and binary paths */
317 void Process::init_memory_map_info()
319 XBT_DEBUG("Get debug information ...");
320 this->maestro_stack_start_ = nullptr;
321 this->maestro_stack_end_ = nullptr;
322 this->object_infos.resize(0);
323 this->binary_info = NULL;
324 this->libsimgrid_info = NULL;
326 struct s_mc_memory_map_re res;
328 if(regcomp(&res.so_re, SO_RE, 0) || regcomp(&res.version_re, VERSION_RE, 0))
329 xbt_die(".so regexp did not compile");
331 std::vector<simgrid::xbt::VmMap> const& maps = this->memory_map_;
333 const char* current_name = NULL;
335 this->object_infos.resize(0);
337 for (size_t i=0; i < maps.size(); i++) {
338 simgrid::xbt::VmMap const& reg = maps[i];
339 const char* pathname = maps[i].pathname.c_str();
342 if (maps[i].pathname.empty()) {
347 // [stack], [vvar], [vsyscall], [vdso] ...
348 if (pathname[0] == '[') {
349 if ((reg.prot & PROT_WRITE) && !memcmp(pathname, "[stack]", 7)) {
350 this->maestro_stack_start_ = remote(reg.start_addr);
351 this->maestro_stack_end_ = remote(reg.end_addr);
357 if (current_name && strcmp(current_name, pathname)==0)
360 current_name = pathname;
361 if (!(reg.prot & PROT_READ) && (reg.prot & PROT_EXEC))
364 const bool is_executable = !i;
365 char* libname = NULL;
366 if (!is_executable) {
367 libname = MC_get_lib_name(pathname, &res);
370 if (MC_is_filtered_lib(libname)) {
376 std::shared_ptr<simgrid::mc::ObjectInformation> info =
377 MC_find_object_info(this->memory_map_, pathname);
378 this->object_infos.push_back(info);
380 this->binary_info = info;
381 else if (libname && MC_is_simgrid_lib(libname))
382 this->libsimgrid_info = info;
387 regfree(&res.version_re);
389 // Resolve time (including accross differents objects):
390 for (auto const& object_info : this->object_infos)
391 MC_post_process_object_info(this, object_info.get());
393 xbt_assert(this->maestro_stack_start_, "Did not find maestro_stack_start");
394 xbt_assert(this->maestro_stack_end_, "Did not find maestro_stack_end");
396 XBT_DEBUG("Get debug information done !");
399 std::shared_ptr<simgrid::mc::ObjectInformation> Process::find_object_info(remote_ptr<void> addr) const
401 for (auto const& object_info : this->object_infos) {
402 if (addr.address() >= (std::uint64_t)object_info->start
403 && addr.address() <= (std::uint64_t)object_info->end) {
410 std::shared_ptr<ObjectInformation> Process::find_object_info_exec(remote_ptr<void> addr) const
412 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos) {
413 if (addr.address() >= (std::uint64_t) info->start_exec
414 && addr.address() <= (std::uint64_t) info->end_exec) {
421 std::shared_ptr<ObjectInformation> Process::find_object_info_rw(remote_ptr<void> addr) const
423 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos) {
424 if (addr.address() >= (std::uint64_t)info->start_rw
425 && addr.address() <= (std::uint64_t)info->end_rw) {
432 simgrid::mc::Frame* Process::find_function(remote_ptr<void> ip) const
434 std::shared_ptr<simgrid::mc::ObjectInformation> info = this->find_object_info_exec(ip);
435 return info ? info->find_function((void*) ip.address()) : nullptr;
438 /** Find (one occurence of) the named variable definition
440 simgrid::mc::Variable* Process::find_variable(const char* name) const
442 // First lookup the variable in the executable shared object.
443 // A global variable used directly by the executable code from a library
444 // is reinstanciated in the executable memory .data/.bss.
445 // We need to look up the variable in the execvutable first.
446 if (this->binary_info) {
447 std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->binary_info;
448 simgrid::mc::Variable* var = info->find_variable(name);
453 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos) {
454 simgrid::mc::Variable* var = info->find_variable(name);
462 void Process::read_variable(const char* name, void* target, size_t size) const
464 simgrid::mc::Variable* var = this->find_variable(name);
466 xbt_die("No simple location for this variable");
467 if (!var->type->full_type)
468 xbt_die("Partial type for %s, cannot check size", name);
469 if ((size_t) var->type->full_type->byte_size != size)
470 xbt_die("Unexpected size for %s (expected %zi, was %zi)",
471 name, size, (size_t) var->type->full_type->byte_size);
472 this->read_bytes(target, size, remote(var->address));
475 char* Process::read_string(remote_ptr<void> address) const
481 char* res = (char*) malloc(len);
485 ssize_t c = pread(this->memory_file, res + off, len - off, (off_t) address.address() + off);
490 xbt_die("Could not read from from remote process");
493 xbt_die("Could not read string from remote process");
495 void* p = memchr(res + off, '\0', c);
502 res = (char*) realloc(res, len);
507 const void *Process::read_bytes(void* buffer, std::size_t size,
508 remote_ptr<void> address, int process_index,
509 AddressSpace::ReadMode mode) const
511 if (process_index != simgrid::mc::ProcessIndexDisabled) {
512 std::shared_ptr<simgrid::mc::ObjectInformation> const& info =
513 this->find_object_info_rw((void*)address.address());
514 // Segment overlap is not handled.
516 if (info.get() && this->privatized(*info)) {
517 if (process_index < 0)
518 xbt_die("Missing process index");
519 if (process_index >= (int) MC_smpi_process_count())
520 xbt_die("Invalid process index");
522 // Read smpi_privatisation_regions from MCed:
523 smpi_privatisation_region_t remote_smpi_privatisation_regions =
524 mc_model_checker->process().read_variable<smpi_privatisation_region_t>(
525 "smpi_privatisation_regions");
527 s_smpi_privatisation_region_t privatisation_region =
528 mc_model_checker->process().read<s_smpi_privatisation_region_t>(
529 remote(remote_smpi_privatisation_regions + process_index));
531 // Address translation in the privaization segment:
532 size_t offset = address.address() - (std::uint64_t)info->start_rw;
533 address = remote((char*)privatisation_region.address + offset);
538 if (pread_whole(this->memory_file, buffer, size, address.address()) < 0)
539 xbt_die("Read from process %lli failed", (long long) this->pid_);
543 /** Write data to a process memory
545 * @param process the process
546 * @param local local memory address (source)
547 * @param remote target process memory address (target)
548 * @param len data size
550 void Process::write_bytes(const void* buffer, size_t len, remote_ptr<void> address)
552 if (pwrite_whole(this->memory_file, buffer, len, address.address()) < 0)
553 xbt_die("Write to process %lli failed", (long long) this->pid_);
556 void Process::clear_bytes(remote_ptr<void> address, size_t len)
558 pthread_once(&zero_buffer_flag, MC_zero_buffer_init);
560 size_t s = len > zero_buffer_size ? zero_buffer_size : len;
561 this->write_bytes(zero_buffer, s, address);
562 address = remote((char*) address.address() + s);
567 void Process::ignore_region(std::uint64_t addr, std::size_t size)
569 IgnoredRegion region;
573 if (ignored_regions_.empty()) {
574 ignored_regions_.push_back(region);
578 unsigned int cursor = 0;
579 IgnoredRegion* current_region = nullptr;
582 int end = ignored_regions_.size() - 1;
583 while (start <= end) {
584 cursor = (start + end) / 2;
585 current_region = &ignored_regions_[cursor];
586 if (current_region->addr == addr) {
587 if (current_region->size == size)
589 else if (current_region->size < size)
593 } else if (current_region->addr < addr)
599 std::size_t position;
600 if (current_region->addr == addr) {
601 if (current_region->size < size) {
602 position = cursor + 1;
606 } else if (current_region->addr < addr) {
607 position = cursor + 1;
611 ignored_regions_.insert(
612 ignored_regions_.begin() + position, region);
615 void Process::reset_soft_dirty()
617 if (this->clear_refs_fd_ < 0) {
618 this->clear_refs_fd_ = open_process_file(pid_, "clear_refs", O_WRONLY|O_CLOEXEC);
619 if (this->clear_refs_fd_ < 0)
620 xbt_die("Could not open clear_refs file for soft-dirty tracking. Run as root?");
622 if(::write(this->clear_refs_fd_, "4\n", 2) != 2)
623 xbt_die("Could not reset softdirty bits");
626 void Process::read_pagemap(uint64_t* pagemap, size_t page_start, size_t page_count)
628 if (pagemap_fd_ < 0) {
629 pagemap_fd_ = open_process_file(pid_, "pagemap", O_RDONLY|O_CLOEXEC);
631 xbt_die("Could not open pagemap file for soft-dirty tracking. Run as root?");
633 ssize_t bytesize = sizeof(uint64_t) * page_count;
634 off_t offset = sizeof(uint64_t) * page_start;
635 if (pread_whole(pagemap_fd_, pagemap, bytesize, offset) != bytesize)
636 xbt_die("Could not read pagemap");
639 void Process::ignore_heap(IgnoredHeapRegion const& region)
641 if (ignored_heap_.empty()) {
642 ignored_heap_.push_back(std::move(region));
646 typedef std::vector<IgnoredHeapRegion>::size_type size_type;
649 size_type end = ignored_heap_.size() - 1;
651 // Binary search the position of insertion:
653 while (start <= end) {
654 cursor = start + (end - start) / 2;
655 auto& current_region = ignored_heap_[cursor];
656 if (current_region.address == region.address)
658 else if (current_region.address < region.address)
660 else if (cursor != 0)
667 // Insert it mc_heap_ignore_region_t:
668 if (ignored_heap_[cursor].address < region.address)
670 ignored_heap_.insert( ignored_heap_.begin() + cursor, region);
673 void Process::unignore_heap(void *address, size_t size)
675 typedef std::vector<IgnoredHeapRegion>::size_type size_type;
678 size_type end = ignored_heap_.size() - 1;
682 while (start <= end) {
683 cursor = (start + end) / 2;
684 auto& region = ignored_heap_[cursor];
685 if (region.address == address) {
686 ignored_heap_.erase(ignored_heap_.begin() + cursor);
688 } else if (region.address < address)
690 else if ((char *) region.address <= ((char *) address + size)) {
691 ignored_heap_.erase(ignored_heap_.begin() + cursor);
693 } else if (cursor != 0)
701 void Process::ignore_local_variable(const char *var_name, const char *frame_name)
703 if (frame_name != nullptr && strcmp(frame_name, "*") == 0)
704 frame_name = nullptr;
705 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info :
707 info->remove_local_variable(var_name, frame_name);