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);
15 static int is_visited_state(){
17 if(_surf_mc_visited == 0)
20 int raw_mem_set = (mmalloc_get_current_heap() == raw_heap);
24 mc_snapshot_t new_state = NULL;
25 new_state = MC_take_snapshot();
29 if(xbt_dynar_is_empty(visited_states)){
32 xbt_dynar_push(visited_states, &new_state);
44 unsigned int cursor = 0;
45 mc_snapshot_t state_test = NULL;
47 xbt_dynar_foreach(visited_states, cursor, state_test){
48 if(XBT_LOG_ISENABLED(mc_dpor, xbt_log_priority_debug))
49 XBT_DEBUG("****** Pair visited #%d ******", cursor + 1);
50 if(snapshot_compare(new_state, state_test, NULL, NULL) == 0){
60 if(xbt_dynar_length(visited_states) == _surf_mc_visited){
61 mc_snapshot_t state_to_remove = NULL;
62 xbt_dynar_shift(visited_states, &state_to_remove);
63 MC_free_snapshot(state_to_remove);
66 xbt_dynar_push(visited_states, &new_state);
79 * \brief Initialize the DPOR exploration algorithm
84 int raw_mem_set = (mmalloc_get_current_heap() == raw_heap);
86 mc_state_t initial_state = NULL;
87 smx_process_t process;
89 /* Create the initial state and push it into the exploration stack */
92 initial_state = MC_state_new();
93 visited_states = xbt_dynar_new(sizeof(mc_snapshot_t), NULL);
97 XBT_DEBUG("**************************************************");
98 XBT_DEBUG("Initial state");
100 /* Wait for requests (schedules processes) */
101 MC_wait_for_requests();
105 /* Get an enabled process and insert it in the interleave set of the initial state */
106 xbt_swag_foreach(process, simix_global->process_list){
107 if(MC_process_is_enabled(process)){
108 MC_state_interleave_process(initial_state, process);
113 xbt_fifo_unshift(mc_stack_safety, initial_state);
126 * \brief Perform the model-checking operation using a depth-first search exploration
127 * with Dynamic Partial Order Reductions
134 smx_simcall_t req = NULL, prev_req = NULL;
135 mc_state_t state = NULL, prev_state = NULL, next_state = NULL, restore_state=NULL;
136 smx_process_t process = NULL;
137 xbt_fifo_item_t item = NULL;
140 while (xbt_fifo_size(mc_stack_safety) > 0) {
142 /* Get current state */
144 xbt_fifo_get_item_content(xbt_fifo_get_first_item(mc_stack_safety));
146 XBT_DEBUG("**************************************************");
147 XBT_DEBUG("Exploration depth=%d (state=%p)(%u interleave)",
148 xbt_fifo_size(mc_stack_safety), state,
149 MC_state_interleave_size(state));
151 /* Update statistics */
152 mc_stats->visited_states++;
154 /* If there are processes to interleave and the maximum depth has not been reached
155 then perform one step of the exploration algorithm */
156 if (xbt_fifo_size(mc_stack_safety) < _surf_mc_max_depth &&
157 (req = MC_state_get_request(state, &value))) {
159 /* Debug information */
160 if(XBT_LOG_ISENABLED(mc_dpor, xbt_log_priority_debug)){
161 req_str = MC_request_to_string(req, value);
162 XBT_DEBUG("Execute: %s", req_str);
166 MC_state_set_executed_request(state, req, value);
167 mc_stats->executed_transitions++;
169 /* Answer the request */
170 SIMIX_simcall_pre(req, value); /* After this call req is no longer usefull */
172 /* Wait for requests (schedules processes) */
173 MC_wait_for_requests();
175 /* Create the new expanded state */
178 next_state = MC_state_new();
180 if(!is_visited_state()){
182 /* Get an enabled process and insert it in the interleave set of the next state */
183 xbt_swag_foreach(process, simix_global->process_list){
184 if(MC_process_is_enabled(process)){
185 MC_state_interleave_process(next_state, process);
186 if((xbt_fifo_size(mc_stack_safety) + 1) != (_surf_mc_max_depth - 1))
191 if(_surf_mc_checkpoint && ((xbt_fifo_size(mc_stack_safety) + 1) % _surf_mc_checkpoint == 0)){
192 next_state->system_state = MC_take_snapshot();
197 XBT_DEBUG("State already visited !");
201 xbt_fifo_unshift(mc_stack_safety, next_state);
204 /* FIXME: Update Statistics
205 mc_stats->state_size +=
206 xbt_setset_set_size(next_state->enabled_transitions);*/
208 /* Let's loop again */
210 /* The interleave set is empty or the maximum depth is reached, let's back-track */
213 if(xbt_fifo_size(mc_stack_safety) == _surf_mc_max_depth)
214 XBT_WARN("/!\\ Max depth reached ! /!\\ ");
216 XBT_DEBUG("There are no more processes to interleave.");
218 /* Trash the current state, no longer needed */
220 xbt_fifo_shift(mc_stack_safety);
221 MC_state_delete(state);
224 /* Check for deadlocks */
225 if(MC_deadlock_check()){
226 MC_show_deadlock(NULL);
231 /* Traverse the stack backwards until a state with a non empty interleave
232 set is found, deleting all the states that have it empty in the way.
233 For each deleted state, check if the request that has generated it
234 (from it's predecesor state), depends on any other previous request
235 executed before it. If it does then add it to the interleave set of the
236 state that executed that previous request. */
238 while ((state = xbt_fifo_shift(mc_stack_safety)) != NULL) {
239 req = MC_state_get_internal_request(state);
240 xbt_fifo_foreach(mc_stack_safety, item, prev_state, mc_state_t) {
241 if(MC_request_depend(req, MC_state_get_internal_request(prev_state))){
242 if(XBT_LOG_ISENABLED(mc_dpor, xbt_log_priority_debug)){
243 XBT_DEBUG("Dependent Transitions:");
244 prev_req = MC_state_get_executed_request(prev_state, &value);
245 req_str = MC_request_to_string(prev_req, value);
246 XBT_DEBUG("%s (state=%p)", req_str, prev_state);
248 prev_req = MC_state_get_executed_request(state, &value);
249 req_str = MC_request_to_string(prev_req, value);
250 XBT_DEBUG("%s (state=%p)", req_str, state);
254 if(!MC_state_process_is_done(prev_state, req->issuer))
255 MC_state_interleave_process(prev_state, req->issuer);
257 XBT_DEBUG("Process %p is in done set", req->issuer);
261 }else if(req->issuer == MC_state_get_executed_request(prev_state, &value)->issuer){
268 if (MC_state_interleave_size(state)) {
269 /* We found a back-tracking point, let's loop */
270 if(_surf_mc_checkpoint){
271 if(state->system_state != NULL){
272 MC_restore_snapshot(state->system_state);
273 xbt_fifo_unshift(mc_stack_safety, state);
274 XBT_DEBUG("Back-tracking to depth %d", xbt_fifo_size(mc_stack_safety));
277 pos = xbt_fifo_size(mc_stack_safety);
278 item = xbt_fifo_get_first_item(mc_stack_safety);
280 restore_state = (mc_state_t) xbt_fifo_get_item_content(item);
281 if(restore_state->system_state != NULL){
284 item = xbt_fifo_get_next_item(item);
288 MC_restore_snapshot(restore_state->system_state);
289 xbt_fifo_unshift(mc_stack_safety, state);
290 XBT_DEBUG("Back-tracking to depth %d", xbt_fifo_size(mc_stack_safety));
292 MC_replay(mc_stack_safety, pos);
295 xbt_fifo_unshift(mc_stack_safety, state);
296 XBT_DEBUG("Back-tracking to depth %d", xbt_fifo_size(mc_stack_safety));
298 MC_replay(mc_stack_safety, -1);
302 MC_state_delete(state);
308 MC_print_statistics(mc_stats);