1 /* Copyright (c) 2008-2012. Da SimGrid Team. All rights reserved. */
3 /* This program is free software; you can redistribute it and/or modify it
4 * under the terms of the license (GNU LGPL) which comes with this package. */
6 #include "mc_private.h"
8 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_dpor, mc,
9 "Logging specific to MC DPOR exploration");
11 xbt_dynar_t visited_states;
13 static int is_visited_state(void);
14 static void visited_state_free(mc_safety_visited_state_t state);
15 static void visited_state_free_voidp(void *s);
17 static void visited_state_free(mc_safety_visited_state_t state){
19 MC_free_snapshot(state->system_state);
24 static void visited_state_free_voidp(void *s){
25 visited_state_free((mc_safety_visited_state_t) * (void **) s);
28 static int is_visited_state(){
30 if(_sg_mc_visited == 0)
33 int raw_mem_set = (mmalloc_get_current_heap() == raw_heap);
37 mc_safety_visited_state_t new_state = NULL;
38 new_state = xbt_new0(s_mc_safety_visited_state_t, 1);
39 new_state->system_state = MC_take_snapshot();
40 new_state->num = mc_stats->expanded_states;
44 if(xbt_dynar_is_empty(visited_states)){
47 xbt_dynar_push(visited_states, &new_state);
59 size_t current_bytes_used = new_state->system_state->heap_bytes_used;
61 unsigned int cursor = 0;
62 int previous_cursor = 0, next_cursor = 0;
64 int end = xbt_dynar_length(visited_states) - 1;
66 mc_safety_visited_state_t state_test = NULL;
67 size_t bytes_used_test;
68 int same_bytes_not_found = 1;
70 while(start <= end && same_bytes_not_found){
71 cursor = (start + end) / 2;
72 state_test = (mc_safety_visited_state_t)xbt_dynar_get_as(visited_states, cursor, mc_safety_visited_state_t);
73 bytes_used_test = state_test->system_state->heap_bytes_used;
74 if(bytes_used_test < current_bytes_used)
76 if(bytes_used_test > current_bytes_used)
78 if(bytes_used_test == current_bytes_used){
79 same_bytes_not_found = 0;
80 if(snapshot_compare(new_state->system_state, state_test->system_state) == 0){
81 xbt_dynar_remove_at(visited_states, cursor, NULL);
82 xbt_dynar_insert_at(visited_states, cursor, &new_state);
83 XBT_DEBUG("State %d already visited ! (equal to state %d)", new_state->num, state_test->num);
90 /* Search another state with same number of bytes used */
91 previous_cursor = cursor - 1;
92 while(previous_cursor >= 0){
93 state_test = (mc_safety_visited_state_t)xbt_dynar_get_as(visited_states, previous_cursor, mc_safety_visited_state_t);
94 bytes_used_test = state_test->system_state->heap_bytes_used;
95 if(bytes_used_test != current_bytes_used)
97 if(snapshot_compare(new_state->system_state, state_test->system_state) == 0){
98 xbt_dynar_remove_at(visited_states, previous_cursor, NULL);
99 xbt_dynar_insert_at(visited_states, previous_cursor, &new_state);
100 XBT_DEBUG("State %d already visited ! (equal to state %d)", new_state->num, state_test->num);
109 next_cursor = cursor + 1;
110 while(next_cursor < xbt_dynar_length(visited_states)){
111 state_test = (mc_safety_visited_state_t)xbt_dynar_get_as(visited_states, next_cursor, mc_safety_visited_state_t);
112 bytes_used_test = state_test->system_state->heap_bytes_used;
113 if(bytes_used_test != current_bytes_used)
115 if(snapshot_compare(new_state->system_state, state_test->system_state) == 0){
116 xbt_dynar_remove_at(visited_states, next_cursor, NULL);
117 xbt_dynar_insert_at(visited_states, next_cursor, &new_state);
118 XBT_DEBUG("State %d already visited ! (equal to state %d)", new_state->num, state_test->num);
131 state_test = (mc_safety_visited_state_t)xbt_dynar_get_as(visited_states, cursor, mc_safety_visited_state_t);
132 bytes_used_test = state_test->system_state->heap_bytes_used;
134 if(bytes_used_test < current_bytes_used)
135 xbt_dynar_insert_at(visited_states, cursor + 1, &new_state);
137 xbt_dynar_insert_at(visited_states, cursor, &new_state);
139 if(xbt_dynar_length(visited_states) > _sg_mc_visited){
140 int min = mc_stats->expanded_states;
141 unsigned int cursor2 = 0;
142 unsigned int index = 0;
143 xbt_dynar_foreach(visited_states, cursor2, state_test){
144 if(state_test->num < min){
146 min = state_test->num;
149 xbt_dynar_remove_at(visited_states, index, NULL);
163 * \brief Initialize the DPOR exploration algorithm
168 int raw_mem_set = (mmalloc_get_current_heap() == raw_heap);
170 mc_state_t initial_state = NULL;
171 smx_process_t process;
173 /* Create the initial state and push it into the exploration stack */
176 initial_state = MC_state_new();
177 visited_states = xbt_dynar_new(sizeof(mc_safety_visited_state_t), visited_state_free_voidp);
181 XBT_DEBUG("**************************************************");
182 XBT_DEBUG("Initial state");
184 /* Wait for requests (schedules processes) */
185 MC_wait_for_requests();
189 /* Get an enabled process and insert it in the interleave set of the initial state */
190 xbt_swag_foreach(process, simix_global->process_list){
191 if(MC_process_is_enabled(process)){
192 MC_state_interleave_process(initial_state, process);
193 XBT_DEBUG("Process %lu enabled with simcall %d", process->pid, process->simcall.call);
197 xbt_fifo_unshift(mc_stack_safety, initial_state);
210 * \brief Perform the model-checking operation using a depth-first search exploration
211 * with Dynamic Partial Order Reductions
218 smx_simcall_t req = NULL, prev_req = NULL, req2 = NULL;
219 s_smx_simcall_t req3;
220 mc_state_t state = NULL, prev_state = NULL, next_state = NULL, restore_state=NULL;
221 smx_process_t process = NULL;
222 xbt_fifo_item_t item = NULL;
223 int pos, i, interleave_size;
224 int interleave_proc[simix_process_maxpid];
226 while (xbt_fifo_size(mc_stack_safety) > 0) {
228 /* Get current state */
230 xbt_fifo_get_item_content(xbt_fifo_get_first_item(mc_stack_safety));
232 XBT_DEBUG("**************************************************");
233 XBT_DEBUG("Exploration depth=%d (state=%p)(%u interleave)",
234 xbt_fifo_size(mc_stack_safety), state,
235 MC_state_interleave_size(state));
237 /* Update statistics */
238 mc_stats->visited_states++;
240 /* If there are processes to interleave and the maximum depth has not been reached
241 then perform one step of the exploration algorithm */
242 if (xbt_fifo_size(mc_stack_safety) < _sg_mc_max_depth &&
243 (req = MC_state_get_request(state, &value))) {
245 /* Debug information */
246 if(XBT_LOG_ISENABLED(mc_dpor, xbt_log_priority_debug)){
247 req_str = MC_request_to_string(req, value);
248 XBT_DEBUG("Execute: %s", req_str);
252 MC_state_set_executed_request(state, req, value);
253 mc_stats->executed_transitions++;
255 if(MC_state_interleave_size(state)){
257 req2 = MC_state_get_internal_request(state);
259 for(i=0; i<simix_process_maxpid; i++)
260 interleave_proc[i] = 0;
262 interleave_size = MC_state_interleave_size(state);
263 while(i < interleave_size){
265 prev_req = MC_state_get_request(state, &value2);
266 if(prev_req != NULL){
267 MC_state_set_executed_request(state, prev_req, value2);
268 prev_req = MC_state_get_internal_request(state);
269 if(MC_request_depend(&req3, prev_req)){
270 XBT_DEBUG("Simcall %d in process %lu dependant with simcall %d in process %lu", req3.call, req3.issuer->pid, prev_req->call, prev_req->issuer->pid);
271 interleave_proc[prev_req->issuer->pid] = 1;
273 XBT_DEBUG("Simcall %d in process %lu independant with simcall %d in process %lu", req3.call, req3.issuer->pid, prev_req->call, prev_req->issuer->pid);
274 MC_state_remove_interleave_process(state, prev_req->issuer);
278 xbt_swag_foreach(process, simix_global->process_list){
279 if(interleave_proc[process->pid] == 1)
280 MC_state_interleave_process(state, process);
285 MC_state_set_executed_request(state, req, value);
287 /* Answer the request */
288 SIMIX_simcall_pre(req, value); /* After this call req is no longer usefull */
290 /* Wait for requests (schedules processes) */
291 MC_wait_for_requests();
293 /* Create the new expanded state */
296 next_state = MC_state_new();
298 if(!is_visited_state()){
300 /* Get an enabled process and insert it in the interleave set of the next state */
301 xbt_swag_foreach(process, simix_global->process_list){
302 if(MC_process_is_enabled(process)){
303 MC_state_interleave_process(next_state, process);
304 XBT_DEBUG("Process %lu enabled with simcall %d", process->pid, process->simcall.call);
308 if(_sg_mc_checkpoint && ((xbt_fifo_size(mc_stack_safety) + 1) % _sg_mc_checkpoint == 0)){
309 next_state->system_state = MC_take_snapshot();
314 xbt_fifo_unshift(mc_stack_safety, next_state);
317 /* Let's loop again */
319 /* The interleave set is empty or the maximum depth is reached, let's back-track */
322 if(xbt_fifo_size(mc_stack_safety) == _sg_mc_max_depth)
323 XBT_WARN("/!\\ Max depth reached ! /!\\ ");
325 XBT_DEBUG("There are no more processes to interleave.");
327 /* Trash the current state, no longer needed */
329 xbt_fifo_shift(mc_stack_safety);
330 MC_state_delete(state);
333 /* Check for deadlocks */
334 if(MC_deadlock_check()){
335 MC_show_deadlock(NULL);
340 /* Traverse the stack backwards until a state with a non empty interleave
341 set is found, deleting all the states that have it empty in the way.
342 For each deleted state, check if the request that has generated it
343 (from it's predecesor state), depends on any other previous request
344 executed before it. If it does then add it to the interleave set of the
345 state that executed that previous request. */
347 while ((state = xbt_fifo_shift(mc_stack_safety)) != NULL) {
348 req = MC_state_get_internal_request(state);
349 xbt_fifo_foreach(mc_stack_safety, item, prev_state, mc_state_t) {
350 if(MC_request_depend(req, MC_state_get_internal_request(prev_state))){
351 if(XBT_LOG_ISENABLED(mc_dpor, xbt_log_priority_debug)){
352 XBT_DEBUG("Dependent Transitions:");
353 prev_req = MC_state_get_executed_request(prev_state, &value);
354 req_str = MC_request_to_string(prev_req, value);
355 XBT_DEBUG("%s (state=%p)", req_str, prev_state);
357 prev_req = MC_state_get_executed_request(state, &value);
358 req_str = MC_request_to_string(prev_req, value);
359 XBT_DEBUG("%s (state=%p)", req_str, state);
365 }else if(req->issuer == MC_state_get_internal_request(prev_state)->issuer){
367 XBT_DEBUG("Simcall %d and %d with same issuer", req->call, MC_state_get_internal_request(prev_state)->call);
372 MC_state_remove_interleave_process(prev_state, req->issuer);
373 XBT_DEBUG("Simcall %d in process %lu independant with simcall %d process %lu", req->call, req->issuer->pid, MC_state_get_internal_request(prev_state)->call, MC_state_get_internal_request(prev_state)->issuer->pid);
378 if (MC_state_interleave_size(state)) {
379 /* We found a back-tracking point, let's loop */
380 if(_sg_mc_checkpoint){
381 if(state->system_state != NULL){
382 MC_restore_snapshot(state->system_state);
383 xbt_fifo_unshift(mc_stack_safety, state);
386 pos = xbt_fifo_size(mc_stack_safety);
387 item = xbt_fifo_get_first_item(mc_stack_safety);
389 restore_state = (mc_state_t) xbt_fifo_get_item_content(item);
390 if(restore_state->system_state != NULL){
393 item = xbt_fifo_get_next_item(item);
397 MC_restore_snapshot(restore_state->system_state);
398 xbt_fifo_unshift(mc_stack_safety, state);
400 MC_replay(mc_stack_safety, pos);
403 xbt_fifo_unshift(mc_stack_safety, state);
405 MC_replay(mc_stack_safety, -1);
407 XBT_DEBUG("Back-tracking to depth %d", xbt_fifo_size(mc_stack_safety));
410 MC_state_delete(state);
416 MC_print_statistics(mc_stats);