1 /* Copyright (c) 2008-2013. 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 #include "mc_private.h"
9 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_dpor, mc,
10 "Logging specific to MC DPOR exploration");
12 /********** Global variables **********/
14 xbt_dynar_t visited_states;
15 xbt_dict_t first_enabled_state;
17 /********** Static functions ***********/
19 static void visited_state_free(mc_visited_state_t state){
21 MC_free_snapshot(state->system_state);
26 static void visited_state_free_voidp(void *s){
27 visited_state_free((mc_visited_state_t) * (void **) s);
30 static mc_visited_state_t visited_state_new(){
32 mc_visited_state_t new_state = NULL;
33 new_state = xbt_new0(s_mc_visited_state_t, 1);
34 new_state->heap_bytes_used = mmalloc_get_bytes_used(std_heap);
35 new_state->nb_processes = xbt_swag_size(simix_global->process_list);
36 new_state->system_state = MC_take_snapshot();
37 new_state->num = mc_stats->expanded_states;
38 new_state->other_num = -1;
44 static int get_search_interval(xbt_dynar_t all_states, mc_visited_state_t state, int *min, int *max){
46 int raw_mem_set = (mmalloc_get_current_heap() == raw_heap);
50 int cursor = 0, previous_cursor, next_cursor;
51 mc_visited_state_t state_test;
53 int end = xbt_dynar_length(all_states) - 1;
56 cursor = (start + end) / 2;
57 state_test = (mc_visited_state_t)xbt_dynar_get_as(all_states, cursor, mc_visited_state_t);
58 if(state_test->nb_processes < state->nb_processes){
60 }else if(state_test->nb_processes > state->nb_processes){
63 if(state_test->heap_bytes_used < state->heap_bytes_used){
65 }else if(state_test->heap_bytes_used > state->heap_bytes_used){
69 previous_cursor = cursor - 1;
70 while(previous_cursor >= 0){
71 state_test = (mc_visited_state_t)xbt_dynar_get_as(all_states, previous_cursor, mc_visited_state_t);
72 if(state_test->nb_processes != state->nb_processes || state_test->heap_bytes_used != state->heap_bytes_used)
74 *min = previous_cursor;
77 next_cursor = cursor + 1;
78 while(next_cursor < xbt_dynar_length(all_states)){
79 state_test = (mc_visited_state_t)xbt_dynar_get_as(all_states, next_cursor, mc_visited_state_t);
80 if(state_test->nb_processes != state->nb_processes || state_test->heap_bytes_used != state->heap_bytes_used)
98 static int is_visited_state(){
100 if(_sg_mc_visited == 0)
103 int raw_mem_set = (mmalloc_get_current_heap() == raw_heap);
107 mc_visited_state_t new_state = visited_state_new();
109 if(xbt_dynar_is_empty(visited_states)){
111 xbt_dynar_push(visited_states, &new_state);
120 int min = -1, max = -1, index;
122 mc_visited_state_t state_test;
124 index = get_search_interval(visited_states, new_state, &min, &max);
126 if(min != -1 && max != -1){
127 res = xbt_parmap_mc_apply(parmap, snapshot_compare, xbt_dynar_get_ptr(visited_states, min), (max-min)+1, new_state);
129 state_test = (mc_visited_state_t)xbt_dynar_get_as(visited_states, (min+res)-1, mc_visited_state_t);
130 if(state_test->other_num == -1)
131 new_state->other_num = state_test->num;
133 new_state->other_num = state_test->other_num;
134 if(dot_output == NULL)
135 XBT_DEBUG("State %d already visited ! (equal to state %d)", new_state->num, state_test->num);
137 XBT_DEBUG("State %d already visited ! (equal to state %d (state %d in dot_output))", new_state->num, state_test->num, new_state->other_num);
138 xbt_dynar_remove_at(visited_states, (min + res) - 1, NULL);
139 xbt_dynar_insert_at(visited_states, (min+res) - 1, &new_state);
142 return new_state->other_num;
144 xbt_dynar_insert_at(visited_states, min, &new_state);
146 state_test = (mc_visited_state_t)xbt_dynar_get_as(visited_states, index, mc_visited_state_t);
147 if(state_test->nb_processes < new_state->nb_processes){
148 xbt_dynar_insert_at(visited_states, index+1, &new_state);
150 if(state_test->heap_bytes_used < new_state->heap_bytes_used)
151 xbt_dynar_insert_at(visited_states, index + 1, &new_state);
153 xbt_dynar_insert_at(visited_states, index, &new_state);
157 if(xbt_dynar_length(visited_states) > _sg_mc_visited){
158 int min2 = mc_stats->expanded_states;
159 unsigned int cursor2 = 0;
160 unsigned int index2 = 0;
161 xbt_dynar_foreach(visited_states, cursor2, state_test){
162 if(state_test->num < min2){
164 min2 = state_test->num;
167 xbt_dynar_remove_at(visited_states, index2, NULL);
179 * \brief Initialize the DPOR exploration algorithm
184 int raw_mem_set = (mmalloc_get_current_heap() == raw_heap);
186 mc_state_t initial_state = NULL;
187 smx_process_t process;
189 /* Create the initial state and push it into the exploration stack */
192 initial_state = MC_state_new();
193 if(_sg_mc_visited > 0)
194 visited_states = xbt_dynar_new(sizeof(mc_visited_state_t), visited_state_free_voidp);
196 first_enabled_state = xbt_dict_new_homogeneous(&xbt_free_f);
200 XBT_DEBUG("**************************************************");
201 XBT_DEBUG("Initial state");
203 /* Wait for requests (schedules processes) */
204 MC_wait_for_requests();
208 /* Get an enabled process and insert it in the interleave set of the initial state */
209 xbt_swag_foreach(process, simix_global->process_list){
210 if(MC_process_is_enabled(process)){
211 MC_state_interleave_process(initial_state, process);
212 if(mc_reduce_kind != e_mc_reduce_none)
217 xbt_fifo_unshift(mc_stack_safety, initial_state);
219 /* To ensure the soundness of DPOR, we have to keep a list of
220 processes which are still enabled at each step of the exploration.
221 If max depth is reached, we interleave them in the state in which they have
222 been enabled for the first time. */
223 xbt_swag_foreach(process, simix_global->process_list){
224 if(MC_process_is_enabled(process)){
225 char *key = bprintf("%lu", process->pid);
226 char *data = bprintf("%d", xbt_fifo_size(mc_stack_safety));
227 xbt_dict_set(first_enabled_state, key, data, NULL);
243 * \brief Perform the model-checking operation using a depth-first search exploration
244 * with Dynamic Partial Order Reductions
249 char *req_str = NULL;
251 smx_simcall_t req = NULL, prev_req = NULL;
252 mc_state_t state = NULL, prev_state = NULL, next_state = NULL, restore_state=NULL;
253 smx_process_t process = NULL;
254 xbt_fifo_item_t item = NULL;
256 int visited_state = -1;
259 while (xbt_fifo_size(mc_stack_safety) > 0) {
261 /* Get current state */
263 xbt_fifo_get_item_content(xbt_fifo_get_first_item(mc_stack_safety));
265 XBT_DEBUG("**************************************************");
266 XBT_DEBUG("Exploration depth=%d (state=%p, num %d)(%u interleave, user_max_depth %d)",
267 xbt_fifo_size(mc_stack_safety), state, state->num,
268 MC_state_interleave_size(state), user_max_depth_reached);
270 /* Update statistics */
271 mc_stats->visited_states++;
273 /* If there are processes to interleave and the maximum depth has not been reached
274 then perform one step of the exploration algorithm */
275 if (xbt_fifo_size(mc_stack_safety) <= _sg_mc_max_depth && !user_max_depth_reached &&
276 (req = MC_state_get_request(state, &value)) && visited_state == -1) {
278 /* Debug information */
279 if(XBT_LOG_ISENABLED(mc_dpor, xbt_log_priority_debug)){
280 req_str = MC_request_to_string(req, value);
281 XBT_DEBUG("Execute: %s", req_str);
286 if(dot_output != NULL)
287 req_str = MC_request_get_dot_output(req, value);
290 MC_state_set_executed_request(state, req, value);
291 mc_stats->executed_transitions++;
294 char *key = bprintf("%lu", req->issuer->pid);
295 xbt_dict_remove(first_enabled_state, key);
299 /* Answer the request */
300 SIMIX_simcall_pre(req, value); /* After this call req is no longer usefull */
302 /* Wait for requests (schedules processes) */
303 MC_wait_for_requests();
305 /* Create the new expanded state */
308 next_state = MC_state_new();
310 if((visited_state = is_visited_state()) == -1){
312 /* Get an enabled process and insert it in the interleave set of the next state */
313 xbt_swag_foreach(process, simix_global->process_list){
314 if(MC_process_is_enabled(process)){
315 MC_state_interleave_process(next_state, process);
316 if(mc_reduce_kind != e_mc_reduce_none)
321 if(_sg_mc_checkpoint && ((xbt_fifo_size(mc_stack_safety) + 1) % _sg_mc_checkpoint == 0)){
322 next_state->system_state = MC_take_snapshot();
325 if(dot_output != NULL)
326 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", state->num, next_state->num, req_str);
330 if(dot_output != NULL)
331 fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", state->num, visited_state, req_str);
335 xbt_fifo_unshift(mc_stack_safety, next_state);
337 /* Insert in dict all enabled processes, if not included yet */
338 xbt_swag_foreach(process, simix_global->process_list){
339 if(MC_process_is_enabled(process)){
340 char *key = bprintf("%lu", process->pid);
341 if(xbt_dict_get_or_null(first_enabled_state, key) == NULL){
342 char *data = bprintf("%d", xbt_fifo_size(mc_stack_safety));
343 xbt_dict_set(first_enabled_state, key, data, NULL);
349 if(dot_output != NULL)
354 /* Let's loop again */
356 /* The interleave set is empty or the maximum depth is reached, let's back-track */
359 if((xbt_fifo_size(mc_stack_safety) > _sg_mc_max_depth) || user_max_depth_reached || visited_state != -1){
361 if(user_max_depth_reached && visited_state == -1)
362 XBT_DEBUG("User max depth reached !");
363 else if(visited_state == -1)
364 XBT_WARN("/!\\ Max depth reached ! /!\\ ");
368 /* Interleave enabled processes in the state in which they have been enabled for the first time */
369 xbt_swag_foreach(process, simix_global->process_list){
370 if(MC_process_is_enabled(process)){
371 char *key = bprintf("%lu", process->pid);
372 enabled = (int)strtoul(xbt_dict_get_or_null(first_enabled_state, key), 0, 10);
374 mc_state_t state_test = NULL;
375 xbt_fifo_item_t item = NULL;
376 int cursor = xbt_fifo_size(mc_stack_safety);
377 xbt_fifo_foreach(mc_stack_safety, item, state_test, mc_state_t){
378 if(cursor-- == enabled){
379 if(!MC_state_process_is_done(state_test, process) && state_test->num != state->num){
380 XBT_DEBUG("Interleave process %lu in state %d", process->pid, state_test->num);
381 MC_state_interleave_process(state_test, process);
391 XBT_DEBUG("There are no more processes to interleave. (depth %d)", xbt_fifo_size(mc_stack_safety) + 1);
395 /* Trash the current state, no longer needed */
397 xbt_fifo_shift(mc_stack_safety);
398 MC_state_delete(state);
399 XBT_DEBUG("Delete state %d at depth %d", state->num, xbt_fifo_size(mc_stack_safety) + 1);
402 /* Check for deadlocks */
403 if(MC_deadlock_check()){
404 MC_show_deadlock(NULL);
409 /* Traverse the stack backwards until a state with a non empty interleave
410 set is found, deleting all the states that have it empty in the way.
411 For each deleted state, check if the request that has generated it
412 (from it's predecesor state), depends on any other previous request
413 executed before it. If it does then add it to the interleave set of the
414 state that executed that previous request. */
416 while ((state = xbt_fifo_shift(mc_stack_safety)) != NULL) {
417 if(mc_reduce_kind != e_mc_reduce_none){
418 req = MC_state_get_internal_request(state);
419 xbt_fifo_foreach(mc_stack_safety, item, prev_state, mc_state_t) {
420 if(MC_request_depend(req, MC_state_get_internal_request(prev_state))){
421 if(XBT_LOG_ISENABLED(mc_dpor, xbt_log_priority_debug)){
422 XBT_DEBUG("Dependent Transitions:");
423 prev_req = MC_state_get_executed_request(prev_state, &value);
424 req_str = MC_request_to_string(prev_req, value);
425 XBT_DEBUG("%s (state=%d)", req_str, prev_state->num);
427 prev_req = MC_state_get_executed_request(state, &value);
428 req_str = MC_request_to_string(prev_req, value);
429 XBT_DEBUG("%s (state=%d)", req_str, state->num);
433 if(!MC_state_process_is_done(prev_state, req->issuer))
434 MC_state_interleave_process(prev_state, req->issuer);
436 XBT_DEBUG("Process %p is in done set", req->issuer);
440 }else if(req->issuer == MC_state_get_internal_request(prev_state)->issuer){
442 XBT_DEBUG("Simcall %d and %d with same issuer", req->call, MC_state_get_internal_request(prev_state)->call);
447 XBT_DEBUG("Simcall %d, process %lu (state %d) and simcall %d, process %lu (state %d) are independant", req->call, req->issuer->pid, state->num, MC_state_get_internal_request(prev_state)->call, MC_state_get_internal_request(prev_state)->issuer->pid, prev_state->num);
453 if (MC_state_interleave_size(state) && xbt_fifo_size(mc_stack_safety) < _sg_mc_max_depth) {
454 /* We found a back-tracking point, let's loop */
455 XBT_DEBUG("Back-tracking to state %d at depth %d", state->num, xbt_fifo_size(mc_stack_safety) + 1);
456 if(_sg_mc_checkpoint){
457 if(state->system_state != NULL){
458 MC_restore_snapshot(state->system_state);
459 xbt_fifo_unshift(mc_stack_safety, state);
462 pos = xbt_fifo_size(mc_stack_safety);
463 item = xbt_fifo_get_first_item(mc_stack_safety);
465 restore_state = (mc_state_t) xbt_fifo_get_item_content(item);
466 if(restore_state->system_state != NULL){
469 item = xbt_fifo_get_next_item(item);
473 MC_restore_snapshot(restore_state->system_state);
474 xbt_fifo_unshift(mc_stack_safety, state);
476 MC_replay(mc_stack_safety, pos);
479 xbt_fifo_unshift(mc_stack_safety, state);
481 MC_replay(mc_stack_safety, -1);
483 XBT_DEBUG("Back-tracking to state %d at depth %d", state->num, xbt_fifo_size(mc_stack_safety));
486 XBT_DEBUG("Delete state %d at depth %d", state->num, xbt_fifo_size(mc_stack_safety) + 1);
487 MC_state_delete(state);
493 MC_print_statistics(mc_stats);