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 "mc_object_info.h"
32 #include "mc_snapshot.h"
33 #include "mc_ignore.h"
35 #include "mc_server.h"
37 #include "mc/Process.hpp"
38 #include "mc/AddressSpace.hpp"
39 #include "mc/ObjectInformation.hpp"
40 #include "mc/Variable.hpp"
42 using simgrid::mc::remote;
46 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_process, mc,
47 "MC process information");
51 #define SO_RE "\\.so[\\.0-9]*$"
52 #define VERSION_RE "-[\\.0-9-]*$"
54 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)
211 Process* process = this;
212 process->socket_ = sockfd;
214 process->running_ = true;
215 process->status_ = 0;
216 process->memory_map_ = get_memory_map(pid);
217 process->cache_flags = MC_PROCESS_CACHE_FLAG_NONE;
218 process->heap = NULL;
219 process->heap_info = NULL;
220 process->init_memory_map_info();
221 process->clear_refs_fd_ = -1;
222 process->pagemap_fd_ = -1;
224 int fd = open_vm(process->pid_, O_RDWR);
226 xbt_die("Could not open file for process virtual address space");
227 process->memory_file = fd;
229 // Read std_heap (is a struct mdesc*):
230 simgrid::mc::Variable* std_heap_var = process->find_variable("__mmalloc_default_mdp");
232 xbt_die("No heap information in the target process");
233 if(!std_heap_var->address)
234 xbt_die("No constant address for this variable");
235 process->read_bytes(&process->heap_address, sizeof(struct mdesc*),
236 remote(std_heap_var->address),
237 simgrid::mc::ProcessIndexDisabled);
239 process->smx_process_infos = MC_smx_process_info_list_new();
240 process->smx_old_process_infos = MC_smx_process_info_list_new();
241 process->unw_addr_space = unw_create_addr_space(&mc_unw_accessors , __BYTE_ORDER);
242 process->unw_underlying_addr_space = unw_create_addr_space(&mc_unw_vmread_accessors, __BYTE_ORDER);
243 process->unw_underlying_context = _UPT_create(pid);
248 Process* process = this;
250 if (this->socket_ >= 0 && close(this->socket_) < 0)
251 xbt_die("Could not close communication socket");
255 process->maestro_stack_start_ = nullptr;
256 process->maestro_stack_end_ = nullptr;
258 xbt_dynar_free(&process->smx_process_infos);
259 xbt_dynar_free(&process->smx_old_process_infos);
261 if (process->memory_file >= 0) {
262 close(process->memory_file);
265 if (process->unw_underlying_addr_space != unw_local_addr_space) {
266 unw_destroy_addr_space(process->unw_underlying_addr_space);
267 _UPT_destroy(process->unw_underlying_context);
269 process->unw_underlying_context = NULL;
270 process->unw_underlying_addr_space = NULL;
272 unw_destroy_addr_space(process->unw_addr_space);
273 process->unw_addr_space = NULL;
275 process->cache_flags = MC_PROCESS_CACHE_FLAG_NONE;
278 process->heap = NULL;
280 free(process->heap_info);
281 process->heap_info = NULL;
283 if (process->clear_refs_fd_ >= 0)
284 close(process->clear_refs_fd_);
285 if (process->pagemap_fd_ >= 0)
286 close(process->pagemap_fd_);
289 /** Refresh the information about the process
291 * Do not use direclty, this is used by the getters when appropriate
292 * in order to have fresh data.
294 void Process::refresh_heap()
296 xbt_assert(mc_mode == MC_MODE_SERVER);
297 // Read/dereference/refresh the std_heap pointer:
299 this->heap = (struct mdesc*) malloc(sizeof(struct mdesc));
301 this->read_bytes(this->heap, sizeof(struct mdesc), remote(this->heap_address),
302 simgrid::mc::ProcessIndexDisabled);
303 this->cache_flags |= MC_PROCESS_CACHE_FLAG_HEAP;
306 /** Refresh the information about the process
308 * Do not use direclty, this is used by the getters when appropriate
309 * in order to have fresh data.
311 void Process::refresh_malloc_info()
313 xbt_assert(mc_mode == MC_MODE_SERVER);
314 if (!(this->cache_flags & MC_PROCESS_CACHE_FLAG_HEAP))
315 this->refresh_heap();
316 // Refresh process->heapinfo:
317 size_t malloc_info_bytesize =
318 (this->heap->heaplimit + 1) * sizeof(malloc_info);
319 this->heap_info = (malloc_info*) realloc(this->heap_info, malloc_info_bytesize);
320 this->read_bytes(this->heap_info, malloc_info_bytesize,
321 remote(this->heap->heapinfo), simgrid::mc::ProcessIndexDisabled);
322 this->cache_flags |= MC_PROCESS_CACHE_FLAG_MALLOC_INFO;
325 /** @brief Finds the range of the different memory segments and binary paths */
326 void Process::init_memory_map_info()
328 XBT_DEBUG("Get debug information ...");
329 this->maestro_stack_start_ = nullptr;
330 this->maestro_stack_end_ = nullptr;
331 this->object_infos.resize(0);
332 this->binary_info = NULL;
333 this->libsimgrid_info = NULL;
335 struct s_mc_memory_map_re res;
337 if(regcomp(&res.so_re, SO_RE, 0) || regcomp(&res.version_re, VERSION_RE, 0))
338 xbt_die(".so regexp did not compile");
340 std::vector<simgrid::mc::VmMap> const& maps = this->memory_map_;
342 const char* current_name = NULL;
344 this->object_infos.resize(0);
346 for (size_t i=0; i < maps.size(); i++) {
347 simgrid::mc::VmMap const& reg = maps[i];
348 const char* pathname = maps[i].pathname.c_str();
351 if (maps[i].pathname.empty()) {
356 // [stack], [vvar], [vsyscall], [vdso] ...
357 if (pathname[0] == '[') {
358 if ((reg.prot & PROT_WRITE) && !memcmp(pathname, "[stack]", 7)) {
359 this->maestro_stack_start_ = remote(reg.start_addr);
360 this->maestro_stack_end_ = remote(reg.end_addr);
366 if (current_name && strcmp(current_name, pathname)==0)
369 current_name = pathname;
370 if (!(reg.prot & PROT_READ) && (reg.prot & PROT_EXEC))
373 const bool is_executable = !i;
374 char* libname = NULL;
375 if (!is_executable) {
376 libname = MC_get_lib_name(pathname, &res);
379 if (MC_is_filtered_lib(libname)) {
385 std::shared_ptr<simgrid::mc::ObjectInformation> info =
386 MC_find_object_info(this->memory_map_, pathname, is_executable);
387 this->object_infos.push_back(info);
389 this->binary_info = info;
390 else if (libname && MC_is_simgrid_lib(libname))
391 this->libsimgrid_info = info;
396 regfree(&res.version_re);
398 // Resolve time (including accross differents objects):
399 for (auto const& object_info : this->object_infos)
400 MC_post_process_object_info(this, object_info.get());
402 xbt_assert(this->maestro_stack_start_, "Did not find maestro_stack_start");
403 xbt_assert(this->maestro_stack_end_, "Did not find maestro_stack_end");
405 XBT_DEBUG("Get debug information done !");
408 std::shared_ptr<simgrid::mc::ObjectInformation> Process::find_object_info(remote_ptr<void> addr) const
410 for (auto const& object_info : this->object_infos) {
411 if (addr.address() >= (std::uint64_t)object_info->start
412 && addr.address() <= (std::uint64_t)object_info->end) {
419 std::shared_ptr<ObjectInformation> Process::find_object_info_exec(remote_ptr<void> addr) const
421 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos) {
422 if (addr.address() >= (std::uint64_t) info->start_exec
423 && addr.address() <= (std::uint64_t) info->end_exec) {
430 std::shared_ptr<ObjectInformation> Process::find_object_info_rw(remote_ptr<void> addr) const
432 for (std::shared_ptr<ObjectInformation> const& info : this->object_infos) {
433 if (addr.address() >= (std::uint64_t)info->start_rw
434 && addr.address() <= (std::uint64_t)info->end_rw) {
441 simgrid::mc::Frame* Process::find_function(remote_ptr<void> ip) const
443 std::shared_ptr<simgrid::mc::ObjectInformation> info = this->find_object_info_exec(ip);
444 return info ? info->find_function((void*) ip.address()) : nullptr;
447 /** Find (one occurence of) the named variable definition
449 simgrid::mc::Variable* Process::find_variable(const char* name) const
451 // First lookup the variable in the executable shared object.
452 // A global variable used directly by the executable code from a library
453 // is reinstanciated in the executable memory .data/.bss.
454 // We need to look up the variable in the execvutable first.
455 if (this->binary_info) {
456 std::shared_ptr<simgrid::mc::ObjectInformation> const& info = this->binary_info;
457 simgrid::mc::Variable* var = info->find_variable(name);
462 for (std::shared_ptr<simgrid::mc::ObjectInformation> const& info : this->object_infos) {
463 simgrid::mc::Variable* var = info->find_variable(name);
471 void Process::read_variable(const char* name, void* target, size_t size) const
473 simgrid::mc::Variable* var = this->find_variable(name);
475 xbt_die("No simple location for this variable");
476 if (!var->type->full_type)
477 xbt_die("Partial type for %s, cannot check size", name);
478 if ((size_t) var->type->full_type->byte_size != size)
479 xbt_die("Unexpected size for %s (expected %zi, was %zi)",
480 name, size, (size_t) var->type->full_type->byte_size);
481 this->read_bytes(target, size, remote(var->address));
484 char* Process::read_string(remote_ptr<void> address) const
490 char* res = (char*) malloc(len);
494 ssize_t c = pread(this->memory_file, res + off, len - off, (off_t) address.address() + off);
499 xbt_die("Could not read from from remote process");
502 xbt_die("Could not read string from remote process");
504 void* p = memchr(res + off, '\0', c);
511 res = (char*) realloc(res, len);
516 const void *Process::read_bytes(void* buffer, std::size_t size,
517 remote_ptr<void> address, int process_index,
518 AddressSpace::ReadMode mode) const
520 if (process_index != simgrid::mc::ProcessIndexDisabled) {
521 std::shared_ptr<simgrid::mc::ObjectInformation> const& info =
522 this->find_object_info_rw((void*)address.address());
523 // Segment overlap is not handled.
525 if (info.get() && info.get()->privatized()) {
526 if (process_index < 0)
527 xbt_die("Missing process index");
528 if (process_index >= (int) MC_smpi_process_count())
529 xbt_die("Invalid process index");
531 // Read smpi_privatisation_regions from MCed:
532 smpi_privatisation_region_t remote_smpi_privatisation_regions =
533 mc_model_checker->process().read_variable<smpi_privatisation_region_t>(
534 "smpi_privatisation_regions");
536 s_smpi_privatisation_region_t privatisation_region =
537 mc_model_checker->process().read<s_smpi_privatisation_region_t>(
538 remote(remote_smpi_privatisation_regions + process_index));
540 // Address translation in the privaization segment:
541 size_t offset = address.address() - (std::uint64_t)info->start_rw;
542 address = remote((char*)privatisation_region.address + offset);
547 if (pread_whole(this->memory_file, buffer, size, address.address()) < 0)
548 xbt_die("Read from process %lli failed", (long long) this->pid_);
552 /** Write data to a process memory
554 * @param process the process
555 * @param local local memory address (source)
556 * @param remote target process memory address (target)
557 * @param len data size
559 void Process::write_bytes(const void* buffer, size_t len, remote_ptr<void> address)
561 if (pwrite_whole(this->memory_file, buffer, len, address.address()) < 0)
562 xbt_die("Write to process %lli failed", (long long) this->pid_);
565 void Process::clear_bytes(remote_ptr<void> address, size_t len)
567 pthread_once(&zero_buffer_flag, MC_zero_buffer_init);
569 size_t s = len > zero_buffer_size ? zero_buffer_size : len;
570 this->write_bytes(zero_buffer, s, address);
571 address = remote((char*) address.address() + s);
576 void Process::ignore_region(std::uint64_t addr, std::size_t size)
578 IgnoredRegion region;
582 if (ignored_regions_.empty()) {
583 ignored_regions_.push_back(region);
587 unsigned int cursor = 0;
588 IgnoredRegion* current_region = nullptr;
591 int end = ignored_regions_.size() - 1;
592 while (start <= end) {
593 cursor = (start + end) / 2;
594 current_region = &ignored_regions_[cursor];
595 if (current_region->addr == addr) {
596 if (current_region->size == size)
598 else if (current_region->size < size)
602 } else if (current_region->addr < addr)
608 std::size_t position;
609 if (current_region->addr == addr) {
610 if (current_region->size < size) {
611 position = cursor + 1;
615 } else if (current_region->addr < addr) {
616 position = cursor + 1;
620 ignored_regions_.insert(
621 ignored_regions_.begin() + position, region);
624 void Process::reset_soft_dirty()
626 if (this->clear_refs_fd_ < 0) {
627 this->clear_refs_fd_ = open_process_file(pid_, "clear_refs", O_WRONLY|O_CLOEXEC);
628 if (this->clear_refs_fd_ < 0)
629 xbt_die("Could not open clear_refs file for soft-dirty tracking. Run as root?");
631 if(::write(this->clear_refs_fd_, "4\n", 2) != 2)
632 xbt_die("Could not reset softdirty bits");
635 void Process::read_pagemap(uint64_t* pagemap, size_t page_start, size_t page_count)
637 if (pagemap_fd_ < 0) {
638 pagemap_fd_ = open_process_file(pid_, "pagemap", O_RDONLY|O_CLOEXEC);
640 xbt_die("Could not open pagemap file for soft-dirty tracking. Run as root?");
642 ssize_t bytesize = sizeof(uint64_t) * page_count;
643 off_t offset = sizeof(uint64_t) * page_start;
644 if (pread_whole(pagemap_fd_, pagemap, bytesize, offset) != bytesize)
645 xbt_die("Could not read pagemap");