1 /* Copyright (c) 2008-2014. 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. */
15 #include "internal_config.h"
16 #include "mc_memory_map.h"
17 #include "mc_private.h"
18 #include "xbt/module.h"
19 #include <xbt/mmalloc.h>
20 #include "../smpi/private.h"
23 #include "xbt/mmalloc/mmprivate.h"
25 #include "../simix/smx_private.h"
27 #include <libunwind.h>
30 #include "mc_private.h"
33 #include "mc_snapshot.h"
34 #include "mc_object_info.h"
38 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_checkpoint, mc,
39 "Logging specific to mc_checkpoint");
41 /************************************ Free functions **************************************/
42 /*****************************************************************************************/
44 static void MC_snapshot_stack_free(mc_snapshot_stack_t s)
47 xbt_dynar_free(&(s->local_variables));
48 xbt_dynar_free(&(s->stack_frames));
49 mc_unw_destroy_context(s->context);
55 static void MC_snapshot_stack_free_voidp(void *s)
57 mc_snapshot_stack_t stack = (mc_snapshot_stack_t) * (void **) s;
58 MC_snapshot_stack_free(stack);
61 static void local_variable_free(local_variable_t v)
67 static void local_variable_free_voidp(void *v)
69 local_variable_free((local_variable_t) * (void **) v);
72 void MC_region_destroy(mc_mem_region_t region)
76 switch(region->storage_type) {
77 case MC_REGION_STORAGE_TYPE_NONE:
79 case MC_REGION_STORAGE_TYPE_FLAT:
80 xbt_free(region->flat.data);
82 case MC_REGION_STORAGE_TYPE_CHUNKED:
83 mc_free_page_snapshot_region(region->chunked.page_numbers, mc_page_count(region->size));
84 xbt_free(region->chunked.page_numbers);
86 case MC_REGION_STORAGE_TYPE_PRIVATIZED:
88 size_t regions_count = region->privatized.regions_count;
89 for (size_t i=0; i!=regions_count; ++i) {
90 MC_region_destroy(region->privatized.regions[i]);
92 free(region->privatized.regions);
99 void MC_free_snapshot(mc_snapshot_t snapshot)
101 for (size_t i = 0; i < snapshot->snapshot_regions_count; i++) {
102 MC_region_destroy(snapshot->snapshot_regions[i]);
104 xbt_free(snapshot->snapshot_regions);
105 xbt_free(snapshot->stack_sizes);
106 xbt_dynar_free(&(snapshot->stacks));
107 xbt_dynar_free(&(snapshot->to_ignore));
108 xbt_dynar_free(&snapshot->ignored_data);
112 /******************************* Snapshot regions ********************************/
113 /*********************************************************************************/
115 static mc_mem_region_t mc_region_new_dense(
116 mc_region_type_t region_type,
117 void *start_addr, void* permanent_addr, size_t size, mc_mem_region_t ref_reg)
119 mc_mem_region_t region = xbt_new(s_mc_mem_region_t, 1);
120 region->region_type = region_type;
121 region->storage_type = MC_REGION_STORAGE_TYPE_FLAT;
122 region->start_addr = start_addr;
123 region->permanent_addr = permanent_addr;
125 region->flat.data = xbt_malloc(size);
126 MC_process_read(&mc_model_checker->process, MC_ADDRESS_SPACE_READ_FLAGS_NONE,
127 region->flat.data, permanent_addr, size,
128 MC_PROCESS_INDEX_DISABLED);
129 XBT_DEBUG("New region : type : %d, data : %p (real addr %p), size : %zu",
130 region_type, region->flat.data, permanent_addr, size);
134 /** @brief Take a snapshot of a given region
137 * @param start_addr Address of the region in the simulated process
138 * @param permanent_addr Permanent address of this data (for privatized variables, this is the virtual address of the privatized mapping)
139 * @param size Size of the data*
140 * @param ref_reg Reference corresponding region
142 static mc_mem_region_t MC_region_new(mc_region_type_t type, void *start_addr, void* permanent_addr, size_t size, mc_mem_region_t ref_reg)
144 if (_sg_mc_sparse_checkpoint) {
145 return mc_region_new_sparse(type, start_addr, permanent_addr, size, ref_reg);
147 return mc_region_new_dense(type, start_addr, permanent_addr, size, ref_reg);
151 /** @brief Restore a region from a snapshot
153 * If we are using per page snapshots, it is possible to use the reference
154 * region in order to do an incremental restoration of the region: the
155 * softclean pages which are shared between the two snapshots do not need
158 * @param reg Target region
159 * @param reg_reg Current region (if not NULL), used for lazy per page restoration
161 static void MC_region_restore(mc_mem_region_t region, mc_mem_region_t ref_region)
163 switch(region->storage_type) {
164 case MC_REGION_STORAGE_TYPE_NONE:
166 xbt_die("Storage type not supported");
169 case MC_REGION_STORAGE_TYPE_FLAT:
170 MC_process_write(&mc_model_checker->process, region->flat.data,
171 region->permanent_addr, region->size);
174 case MC_REGION_STORAGE_TYPE_CHUNKED:
175 mc_region_restore_sparse(&mc_model_checker->process, region, ref_region);
178 case MC_REGION_STORAGE_TYPE_PRIVATIZED:
180 bool has_ref_regions = ref_region &&
181 ref_region->storage_type == MC_REGION_STORAGE_TYPE_PRIVATIZED;
182 size_t process_count = region->privatized.regions_count;
183 for (size_t i = 0; i < process_count; i++) {
184 MC_region_restore(region->privatized.regions[i],
185 has_ref_regions ? ref_region->privatized.regions[i] : NULL);
192 // FIXME, multiple privatisation regions
193 // FIXME, cross-process
195 void* MC_privatization_address(mc_process_t process, int process_index)
197 xbt_assert(process_index >= 0);
198 return smpi_privatisation_regions[process_index].address;
201 static mc_mem_region_t MC_region_new_privatized(
202 mc_region_type_t region_type, void *start_addr, void* permanent_addr, size_t size,
203 mc_mem_region_t ref_reg)
205 size_t process_count = smpi_process_count();
206 mc_mem_region_t region = xbt_new(s_mc_mem_region_t, 1);
207 region->region_type = region_type;
208 region->storage_type = MC_REGION_STORAGE_TYPE_PRIVATIZED;
209 region->start_addr = start_addr;
210 region->permanent_addr = permanent_addr;
212 region->privatized.regions_count = process_count;
213 region->privatized.regions = xbt_new(mc_mem_region_t, process_count);
215 for (size_t i = 0; i < process_count; i++) {
216 mc_mem_region_t ref_subreg = NULL;
217 if (ref_reg && ref_reg->storage_type == MC_REGION_STORAGE_TYPE_PRIVATIZED)
218 ref_subreg = ref_reg->privatized.regions[i];
219 region->privatized.regions[i] =
220 MC_region_new(region_type, start_addr,
221 MC_privatization_address(&mc_model_checker->process, i), size,
228 static void MC_snapshot_add_region(int index, mc_snapshot_t snapshot, mc_region_type_t type,
229 mc_object_info_t object_info,
230 void *start_addr, void* permanent_addr, size_t size)
232 if (type == MC_REGION_TYPE_DATA)
233 xbt_assert(object_info, "Missing object info for object.");
234 else if (type == MC_REGION_TYPE_HEAP)
235 xbt_assert(!object_info, "Unexpected object info for heap region.");
237 mc_mem_region_t ref_reg = NULL;
238 if (mc_model_checker->parent_snapshot)
239 ref_reg = mc_model_checker->parent_snapshot->snapshot_regions[index];
241 mc_mem_region_t region;
242 const bool privatization_aware = MC_object_info_is_privatized(object_info);
243 if (privatization_aware && smpi_process_count())
244 region = MC_region_new_privatized(type, start_addr, permanent_addr, size, ref_reg);
246 region = MC_region_new(type, start_addr, permanent_addr, size, ref_reg);
248 region->object_info = object_info;
249 snapshot->snapshot_regions[index] = region;
253 static void MC_get_memory_regions(mc_process_t process, mc_snapshot_t snapshot)
255 const size_t n = process->object_infos_size;
256 snapshot->snapshot_regions_count = n + 1;
257 snapshot->snapshot_regions = xbt_new0(mc_mem_region_t, n + 1);
259 for (size_t i = 0; i!=n; ++i) {
260 mc_object_info_t object_info = process->object_infos[i];
261 MC_snapshot_add_region(i, snapshot, MC_REGION_TYPE_DATA, object_info,
262 object_info->start_rw, object_info->start_rw,
263 object_info->end_rw - object_info->start_rw);
266 xbt_mheap_t heap = MC_process_get_heap(process);
267 void *start_heap = heap->base;
268 void *end_heap = heap->breakval;
270 MC_snapshot_add_region(n, snapshot, MC_REGION_TYPE_HEAP, NULL,
271 start_heap, start_heap,
272 (char *) end_heap - (char *) start_heap);
273 snapshot->heap_bytes_used = mmalloc_get_bytes_used_remote(
275 MC_process_get_malloc_info(process));
278 if (smpi_privatize_global_variables && smpi_process_count()) {
279 // FIXME, cross-process
280 snapshot->privatization_index = smpi_loaded_page;
284 snapshot->privatization_index = MC_PROCESS_INDEX_MISSING;
288 /** \brief Fills the position of the segments (executable, read-only, read/write).
290 * `dl_iterate_phdr` would be more robust but would not work in cross-process.
292 void MC_find_object_address(memory_map_t maps, mc_object_info_t result)
296 const char *name = basename(result->file_name);
297 while (i < maps->mapsize) {
298 reg = maps->regions[i];
299 if (maps->regions[i].pathname == NULL
300 || strcmp(basename(maps->regions[i].pathname), name)) {
302 } else if ((reg.prot & PROT_WRITE)) {
303 xbt_assert(!result->start_rw,
304 "Multiple read-write segments for %s, not supported",
305 maps->regions[i].pathname);
306 result->start_rw = reg.start_addr;
307 result->end_rw = reg.end_addr;
308 // .bss is usually after the .data:
309 s_map_region_t *next = &(maps->regions[i + 1]);
310 if (next->pathname == NULL && (next->prot & PROT_WRITE)
311 && next->start_addr == reg.end_addr) {
312 result->end_rw = maps->regions[i + 1].end_addr;
314 } else if ((reg.prot & PROT_READ) && (reg.prot & PROT_EXEC)) {
315 xbt_assert(!result->start_exec,
316 "Multiple executable segments for %s, not supported",
317 maps->regions[i].pathname);
318 result->start_exec = reg.start_addr;
319 result->end_exec = reg.end_addr;
320 } else if ((reg.prot & PROT_READ) && !(reg.prot & PROT_EXEC)) {
321 xbt_assert(!result->start_ro,
322 "Multiple read only segments for %s, not supported",
323 maps->regions[i].pathname);
324 result->start_ro = reg.start_addr;
325 result->end_ro = reg.end_addr;
330 result->start = result->start_rw;
331 if ((const void*) result->start_ro > result->start)
332 result->start = result->start_ro;
333 if ((const void*) result->start_exec > result->start)
334 result->start = result->start_exec;
336 result->end = result->end_rw;
337 if (result->end_ro && (const void*) result->end_ro < result->end)
338 result->end = result->end_ro;
339 if (result->end_exec && (const void*) result->end_exec > result->end)
340 result->end = result->end_exec;
342 xbt_assert(result->file_name);
343 xbt_assert(result->start_rw);
344 xbt_assert(result->start_exec);
347 /************************************* Take Snapshot ************************************/
348 /****************************************************************************************/
350 /** \brief Checks whether the variable is in scope for a given IP.
352 * A variable may be defined only from a given value of IP.
354 * \param var Variable description
355 * \param frame Scope description
356 * \param ip Instruction pointer
357 * \return true if the variable is valid
359 static bool mc_valid_variable(dw_variable_t var, dw_frame_t scope,
362 // The variable is not yet valid:
363 if ((const void *) ((const char *) scope->low_pc + var->start_scope) > ip)
369 static void mc_fill_local_variables_values(mc_stack_frame_t stack_frame,
370 dw_frame_t scope, int process_index, xbt_dynar_t result)
372 mc_process_t process = &mc_model_checker->process;
374 void *ip = (void *) stack_frame->ip;
375 if (ip < scope->low_pc || ip >= scope->high_pc)
379 dw_variable_t current_variable;
380 xbt_dynar_foreach(scope->variables, cursor, current_variable) {
382 if (!mc_valid_variable(current_variable, scope, (void *) stack_frame->ip))
386 // FIXME, get rid of `region_type`
387 if ((long) stack_frame->ip > (long) process->libsimgrid_info->start_exec)
392 local_variable_t new_var = xbt_new0(s_local_variable_t, 1);
393 new_var->subprogram = stack_frame->frame;
394 new_var->ip = stack_frame->ip;
395 new_var->name = xbt_strdup(current_variable->name);
396 new_var->type = current_variable->type;
397 new_var->region = region_type;
399 if (current_variable->address != NULL) {
400 new_var->address = current_variable->address;
401 } else if (current_variable->locations.size != 0) {
402 s_mc_location_t location;
403 // FIXME, cross-process support
404 mc_dwarf_resolve_locations(&location, ¤t_variable->locations,
405 current_variable->object_info,
406 &(stack_frame->unw_cursor),
407 (void *) stack_frame->frame_base,
408 NULL, process_index);
410 switch(mc_get_location_type(&location)) {
411 case MC_LOCATION_TYPE_ADDRESS:
412 new_var->address = location.memory_location;
414 case MC_LOCATION_TYPE_REGISTER:
416 xbt_die("Cannot handle non-address variable");
420 xbt_die("No address");
423 xbt_dynar_push(result, &new_var);
426 // Recursive processing of nested scopes:
427 dw_frame_t nested_scope = NULL;
428 xbt_dynar_foreach(scope->scopes, cursor, nested_scope) {
429 mc_fill_local_variables_values(stack_frame, nested_scope, process_index, result);
433 static xbt_dynar_t MC_get_local_variables_values(xbt_dynar_t stack_frames, int process_index)
436 unsigned cursor1 = 0;
437 mc_stack_frame_t stack_frame;
438 xbt_dynar_t variables =
439 xbt_dynar_new(sizeof(local_variable_t), local_variable_free_voidp);
441 xbt_dynar_foreach(stack_frames, cursor1, stack_frame) {
442 mc_fill_local_variables_values(stack_frame, stack_frame->frame, process_index, variables);
448 static void MC_stack_frame_free_voipd(void *s)
450 mc_stack_frame_t stack_frame = *(mc_stack_frame_t *) s;
452 xbt_free(stack_frame->frame_name);
453 xbt_free(stack_frame);
457 static xbt_dynar_t MC_unwind_stack_frames(mc_unw_context_t stack_context)
459 mc_process_t process = &mc_model_checker->process;
461 xbt_dynar_new(sizeof(mc_stack_frame_t), MC_stack_frame_free_voipd);
465 // TODO, check condition check (unw_init_local==0 means end of frame)
466 if (mc_unw_init_cursor(&c, stack_context) != 0) {
468 xbt_die("Could not initialize stack unwinding");
473 mc_stack_frame_t stack_frame = xbt_new(s_mc_stack_frame_t, 1);
474 xbt_dynar_push(result, &stack_frame);
476 stack_frame->unw_cursor = c;
480 unw_get_reg(&c, UNW_REG_IP, &ip);
481 unw_get_reg(&c, UNW_REG_SP, &sp);
483 stack_frame->ip = ip;
484 stack_frame->sp = sp;
486 // TODO, use real addresses in frame_t instead of fixing it here
488 dw_frame_t frame = MC_process_find_function(process, (void *) ip);
489 stack_frame->frame = frame;
492 stack_frame->frame_name = xbt_strdup(frame->name);
493 stack_frame->frame_base =
494 (unw_word_t) mc_find_frame_base(frame, frame->object_info, &c);
496 stack_frame->frame_base = 0;
497 stack_frame->frame_name = NULL;
500 /* Stop before context switch with maestro */
501 if (frame != NULL && frame->name != NULL
502 && !strcmp(frame->name, "smx_ctx_sysv_wrapper"))
505 int ret = unw_step(&c);
507 xbt_die("Unexpected end of stack.");
508 } else if (ret < 0) {
509 xbt_die("Error while unwinding stack");
513 if (xbt_dynar_length(result) == 0) {
514 XBT_INFO("unw_init_local failed");
521 static xbt_dynar_t MC_take_snapshot_stacks(mc_snapshot_t * snapshot)
525 xbt_dynar_new(sizeof(s_mc_snapshot_stack_t),
526 MC_snapshot_stack_free_voidp);
528 unsigned int cursor = 0;
529 stack_region_t current_stack;
531 // FIXME, cross-process support (stack_areas)
532 xbt_dynar_foreach(stacks_areas, cursor, current_stack) {
533 mc_snapshot_stack_t st = xbt_new(s_mc_snapshot_stack_t, 1);
535 unw_context_t* original_context = (unw_context_t*) current_stack->context;
537 st->context = xbt_new0(s_mc_unw_context_t, 1);
538 if (mc_unw_init_context(st->context, &mc_model_checker->process,
539 original_context) < 0) {
540 xbt_die("Could not initialise the libunwind context.");
543 st->stack_frames = MC_unwind_stack_frames(st->context);
544 st->local_variables = MC_get_local_variables_values(st->stack_frames, current_stack->process_index);
545 st->process_index = current_stack->process_index;
547 unw_word_t sp = xbt_dynar_get_as(st->stack_frames, 0, mc_stack_frame_t)->sp;
549 xbt_dynar_push(res, &st);
550 (*snapshot)->stack_sizes =
551 xbt_realloc((*snapshot)->stack_sizes, (cursor + 1) * sizeof(size_t));
552 (*snapshot)->stack_sizes[cursor] =
553 (char*) current_stack->address + current_stack->size - (char*) sp;
560 // FIXME, cross-process support (mc_heap_comparison_ignore)
561 static xbt_dynar_t MC_take_snapshot_ignore()
564 if (mc_heap_comparison_ignore == NULL)
568 xbt_dynar_new(sizeof(mc_heap_ignore_region_t),
569 heap_ignore_region_free_voidp);
571 unsigned int cursor = 0;
572 mc_heap_ignore_region_t current_region;
574 xbt_dynar_foreach(mc_heap_comparison_ignore, cursor, current_region) {
575 mc_heap_ignore_region_t new_region = NULL;
576 new_region = xbt_new0(s_mc_heap_ignore_region_t, 1);
577 new_region->address = current_region->address;
578 new_region->size = current_region->size;
579 new_region->block = current_region->block;
580 new_region->fragment = current_region->fragment;
581 xbt_dynar_push(cpy, &new_region);
588 static void mc_free_snapshot_ignored_data_pvoid(void* data) {
589 mc_snapshot_ignored_data_t ignored_data = (mc_snapshot_ignored_data_t) data;
590 free(ignored_data->data);
593 static void MC_snapshot_handle_ignore(mc_snapshot_t snapshot)
595 xbt_assert(snapshot->process);
596 snapshot->ignored_data = xbt_dynar_new(sizeof(s_mc_snapshot_ignored_data_t), mc_free_snapshot_ignored_data_pvoid);
599 unsigned int cursor = 0;
600 mc_checkpoint_ignore_region_t region;
601 // FIXME, cross-process support (mc_checkpoint_ignore)
602 xbt_dynar_foreach (mc_model_checker->process.checkpoint_ignore, cursor, region) {
603 s_mc_snapshot_ignored_data_t ignored_data;
604 ignored_data.start = region->addr;
605 ignored_data.size = region->size;
606 ignored_data.data = malloc(region->size);
607 // TODO, we should do this once per privatization segment:
608 MC_process_read(snapshot->process,
609 MC_ADDRESS_SPACE_READ_FLAGS_NONE,
610 ignored_data.data, region->addr, region->size, MC_PROCESS_INDEX_DISABLED);
611 xbt_dynar_push(snapshot->ignored_data, &ignored_data);
615 xbt_dynar_foreach (mc_model_checker->process.checkpoint_ignore, cursor, region) {
616 MC_process_clear_memory(snapshot->process, region->addr, region->size);
621 static void MC_snapshot_ignore_restore(mc_snapshot_t snapshot)
623 unsigned int cursor = 0;
624 s_mc_snapshot_ignored_data_t ignored_data;
625 xbt_dynar_foreach (snapshot->ignored_data, cursor, ignored_data) {
626 MC_process_write(snapshot->process,
627 ignored_data.data, ignored_data.start, ignored_data.size);
631 /** @brief Can we remove this snapshot?
633 * Some snapshots cannot be removed (yet) because we need them
638 int mc_important_snapshot(mc_snapshot_t snapshot)
640 // We need this snapshot in order to know which
641 // pages needs to be stored in the next snapshot.
642 // This field is only non-NULL when using soft-dirty
644 if (snapshot == mc_model_checker->parent_snapshot)
650 static void MC_get_current_fd(mc_snapshot_t snapshot)
653 snapshot->total_fd = 0;
655 const size_t fd_dir_path_size = 20;
656 char fd_dir_path[fd_dir_path_size];
657 if (snprintf(fd_dir_path, fd_dir_path_size,
658 "/proc/%lli/fd", (long long int) snapshot->process->pid) > fd_dir_path_size)
659 xbt_die("Unexpected buffer is too small for fd_dir_path");
661 DIR* fd_dir = opendir(fd_dir_path);
663 xbt_die("Cannot open directory '/proc/self/fd'\n");
666 struct dirent* fd_number;
667 while ((fd_number = readdir(fd_dir))) {
669 int fd_value = atoi(fd_number->d_name);
674 const size_t source_size = 25;
676 if (snprintf(source, source_size, "/proc/%lli/fd/%s",
677 (long long int) snapshot->process->pid, fd_number->d_name) > source_size)
678 xbt_die("Unexpected buffer is too small for fd %s", fd_number->d_name);
680 const size_t link_size = 200;
682 int res = readlink(source, link, link_size);
684 xbt_die("Could not read link for %s", source);
687 xbt_die("Buffer to small for link of %s", source);
691 if(smpi_is_privatisation_file(link))
694 // This is (probably) the DIR* we are reading:
695 // TODO, read all the file entries at once and close the DIR.*
696 if(strcmp(fd_dir_path, link) == 0)
699 // We don't handle them.
700 // It does not mean we should silently ignore them however.
701 if (strncmp(link, "pipe:", 5) == 0 || strncmp(link, "socket:", 7) == 0)
704 // This is probably a shared memory used by lttng-ust:
705 if(strncmp("/dev/shm/ust-shm-tmp-", link, 21)==0)
708 // Add an entry for this FD in the snapshot:
709 fd_infos_t fd = xbt_new0(s_fd_infos_t, 1);
710 fd->filename = strdup(link);
711 fd->number = fd_value;
712 fd->flags = fcntl(fd_value, F_GETFL) | fcntl(fd_value, F_GETFD) ;
713 fd->current_position = lseek(fd_value, 0, SEEK_CUR);
714 snapshot->current_fd = xbt_realloc(snapshot->current_fd, (total_fd + 1) * sizeof(fd_infos_t));
715 snapshot->current_fd[total_fd] = fd;
719 snapshot->total_fd = total_fd;
723 static s_mc_address_space_class_t mc_snapshot_class = {
724 .read = (void*) &MC_snapshot_read
727 mc_snapshot_t MC_take_snapshot(int num_state)
729 mc_process_t mc_process = &mc_model_checker->process;
730 mc_snapshot_t snapshot = xbt_new0(s_mc_snapshot_t, 1);
731 snapshot->process = mc_process;
732 snapshot->address_space.address_space_class = &mc_snapshot_class;
734 snapshot->enabled_processes = xbt_dynar_new(sizeof(int), NULL);
735 smx_process_t process;
736 // FIXME, cross-process support (simix_global->process_list)
737 xbt_swag_foreach(process, simix_global->process_list) {
738 xbt_dynar_push_as(snapshot->enabled_processes, int, (int)process->pid);
741 MC_snapshot_handle_ignore(snapshot);
743 MC_get_current_fd(snapshot);
745 const bool use_soft_dirty = _sg_mc_sparse_checkpoint
747 && MC_process_is_self(mc_process);
749 /* Save the std heap and the writable mapped pages of libsimgrid and binary */
750 MC_get_memory_regions(mc_process, snapshot);
752 mc_softdirty_reset();
754 snapshot->to_ignore = MC_take_snapshot_ignore();
756 if (_sg_mc_visited > 0 || strcmp(_sg_mc_property_file, "")) {
758 MC_take_snapshot_stacks(&snapshot);
759 if (_sg_mc_hash && snapshot->stacks != NULL) {
760 snapshot->hash = mc_hash_processes_state(num_state, snapshot->stacks);
768 MC_snapshot_ignore_restore(snapshot);
770 mc_model_checker->parent_snapshot = snapshot;
775 void MC_restore_snapshot_regions(mc_snapshot_t snapshot)
777 mc_snapshot_t parent_snapshot = mc_model_checker->parent_snapshot;
779 const size_t n = snapshot->snapshot_regions_count;
780 for (size_t i = 0; i < n; i++) {
781 // For privatized, variables we decided it was not necessary to take the snapshot:
782 if (snapshot->snapshot_regions[i])
783 MC_region_restore(snapshot->snapshot_regions[i],
784 parent_snapshot ? parent_snapshot->snapshot_regions[i] : NULL);
788 if(snapshot->privatization_index >= 0) {
789 // We just rewrote the global variables.
790 // The privatisation segment SMPI thinks
791 // is mapped might be inconsistent with the segment which
792 // is really mapped in memory (kernel state).
793 // We ask politely SMPI to map the segment anyway,
794 // even if it thinks it is the current one:
795 smpi_really_switch_data_segment(snapshot->privatization_index);
800 // FIXME, cross-process support ~ we need to implement this on the app side
801 // or use some form of [remote syscall execution](http://criu.org/Remote_syscall_execution)
802 // based on [parasite code execution](http://criu.org/Parasite_code).
804 void MC_restore_snapshot_fds(mc_snapshot_t snapshot)
808 for(i=0; i < snapshot->total_fd; i++){
810 new_fd = open(snapshot->current_fd[i]->filename, snapshot->current_fd[i]->flags);
812 xbt_die("Could not reopen the file %s fo restoring the file descriptor",
813 snapshot->current_fd[i]->filename);
815 if(new_fd != -1 && new_fd != snapshot->current_fd[i]->number){
816 dup2(new_fd, snapshot->current_fd[i]->number);
817 //fprintf(stderr, "%p\n", fdopen(snapshot->current_fd[i]->number, "rw"));
820 lseek(snapshot->current_fd[i]->number, snapshot->current_fd[i]->current_position, SEEK_SET);
824 void MC_restore_snapshot(mc_snapshot_t snapshot)
826 const bool use_soft_dirty = _sg_mc_sparse_checkpoint
828 && MC_process_is_self(&mc_model_checker->process);
830 MC_restore_snapshot_regions(snapshot);
831 MC_restore_snapshot_fds(snapshot);
832 if (use_soft_dirty) {
833 mc_softdirty_reset();
835 MC_snapshot_ignore_restore(snapshot);
836 if (use_soft_dirty) {
837 mc_model_checker->parent_snapshot = snapshot;
840 mc_model_checker->process.cache_flags = 0;
843 mc_snapshot_t simcall_HANDLER_mc_snapshot(smx_simcall_t simcall)
845 return MC_take_snapshot(1);
848 void *MC_snapshot(void)
850 return simcall_mc_snapshot();