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_stateful == 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_stateful){
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 xbt_swag_foreach(process, simix_global->process_list){
106 if(MC_process_is_enabled(process)){
107 XBT_DEBUG("Process %lu enabled with simcall : %d", process->pid, (&process->simcall)->call);
111 /* Get an enabled process and insert it in the interleave set of the initial state */
112 xbt_swag_foreach(process, simix_global->process_list){
113 if(MC_process_is_enabled(process)){
114 MC_state_interleave_process(initial_state, process);
119 xbt_fifo_unshift(mc_stack_safety, initial_state);
129 /* FIXME: Update Statistics
130 mc_stats->state_size +=
131 xbt_setset_set_size(initial_state->enabled_transitions); */
136 * \brief Perform the model-checking operation using a depth-first search exploration
137 * with Dynamic Partial Order Reductions
144 smx_simcall_t req = NULL, prev_req = NULL;
145 mc_state_t state = NULL, prev_state = NULL, next_state = NULL, restore_state=NULL;
146 smx_process_t process = NULL;
147 xbt_fifo_item_t item = NULL;
150 while (xbt_fifo_size(mc_stack_safety) > 0) {
152 /* Get current state */
154 xbt_fifo_get_item_content(xbt_fifo_get_first_item(mc_stack_safety));
156 XBT_DEBUG("**************************************************");
157 XBT_DEBUG("Exploration depth=%d (state=%p)(%u interleave)",
158 xbt_fifo_size(mc_stack_safety), state,
159 MC_state_interleave_size(state));
161 /* Update statistics */
162 mc_stats->visited_states++;
164 /* If there are processes to interleave and the maximum depth has not been reached
165 then perform one step of the exploration algorithm */
166 if (xbt_fifo_size(mc_stack_safety) < _surf_mc_max_depth &&
167 (req = MC_state_get_request(state, &value))) {
169 /* Debug information */
170 if(XBT_LOG_ISENABLED(mc_dpor, xbt_log_priority_debug)){
171 req_str = MC_request_to_string(req, value);
172 XBT_DEBUG("Execute: %s", req_str);
176 MC_state_set_executed_request(state, req, value);
177 mc_stats->executed_transitions++;
179 /* Answer the request */
180 SIMIX_simcall_pre(req, value); /* After this call req is no longer usefull */
182 /* Wait for requests (schedules processes) */
183 MC_wait_for_requests();
185 /* Create the new expanded state */
188 next_state = MC_state_new();
190 if(!is_visited_state()){
192 /* Get an enabled process and insert it in the interleave set of the next state */
193 xbt_swag_foreach(process, simix_global->process_list){
194 if(MC_process_is_enabled(process)){
195 MC_state_interleave_process(next_state, process);
196 XBT_DEBUG("Process %lu enabled with simcall : %d", process->pid, (&process->simcall)->call);
201 if(_surf_mc_checkpoint && ((xbt_fifo_size(mc_stack_safety) + 1) % _surf_mc_checkpoint == 0)){
202 next_state->system_state = MC_take_snapshot();
207 XBT_DEBUG("State already visited !");
211 xbt_fifo_unshift(mc_stack_safety, next_state);
214 /* FIXME: Update Statistics
215 mc_stats->state_size +=
216 xbt_setset_set_size(next_state->enabled_transitions);*/
218 /* Let's loop again */
220 /* The interleave set is empty or the maximum depth is reached, let's back-track */
223 if(xbt_fifo_size(mc_stack_safety) == _surf_mc_max_depth){
225 XBT_WARN("/!\\ Max depth reached ! /!\\ ");
227 XBT_WARN("/!\\ But, there are still processes to interleave. Model-checker will not be able to ensure the soundness of the verification from now. /!\\ ");
228 XBT_WARN("Notice : the default value of max depth is 1000 but you can change it with cfg=model-check/max_depth:value.");
233 XBT_DEBUG("There are no more processes to interleave.");
237 /* Trash the current state, no longer needed */
239 xbt_fifo_shift(mc_stack_safety);
240 MC_state_delete(state);
243 /* Check for deadlocks */
244 if(MC_deadlock_check()){
245 MC_show_deadlock(NULL);
250 /* Traverse the stack backwards until a state with a non empty interleave
251 set is found, deleting all the states that have it empty in the way.
252 For each deleted state, check if the request that has generated it
253 (from it's predecesor state), depends on any other previous request
254 executed before it. If it does then add it to the interleave set of the
255 state that executed that previous request. */
257 while ((state = xbt_fifo_shift(mc_stack_safety)) != NULL) {
258 if(MC_state_interleave_size(state) == 0){
259 req = MC_state_get_internal_request(state);
260 xbt_fifo_foreach(mc_stack_safety, item, prev_state, mc_state_t) {
261 if(MC_request_depend(req, MC_state_get_internal_request(prev_state))){
262 if(XBT_LOG_ISENABLED(mc_dpor, xbt_log_priority_debug)){
263 XBT_DEBUG("Dependent Transitions:");
264 prev_req = MC_state_get_executed_request(prev_state, &value);
265 req_str = MC_request_to_string(prev_req, value);
266 XBT_DEBUG("%s (state=%p)", req_str, prev_state);
268 prev_req = MC_state_get_executed_request(state, &value);
269 req_str = MC_request_to_string(prev_req, value);
270 XBT_DEBUG("%s (state=%p)", req_str, state);
274 /*if(!MC_state_process_is_done(prev_state, req->issuer))
275 MC_state_interleave_process(prev_state, req->issuer);
277 XBT_DEBUG("Process %p is in done set", req->issuer);*/
284 //XBT_DEBUG("Independant transitions : (%lu) %d - (%lu) %d", req->issuer->pid, req->call, MC_state_get_internal_request(prev_state)->issuer->pid, MC_state_get_internal_request(prev_state)->call);
285 MC_state_remove_interleave_process(prev_state, req->issuer);
290 if (MC_state_interleave_size(state)) {
291 /* We found a back-tracking point, let's loop */
292 if(_surf_mc_checkpoint){
293 if(state->system_state != NULL){
294 MC_restore_snapshot(state->system_state);
295 xbt_fifo_unshift(mc_stack_safety, state);
296 XBT_DEBUG("Back-tracking to depth %d", xbt_fifo_size(mc_stack_safety));
299 pos = xbt_fifo_size(mc_stack_safety);
300 item = xbt_fifo_get_first_item(mc_stack_safety);
302 restore_state = (mc_state_t) xbt_fifo_get_item_content(item);
303 if(restore_state->system_state != NULL){
306 item = xbt_fifo_get_next_item(item);
310 MC_restore_snapshot(restore_state->system_state);
311 xbt_fifo_unshift(mc_stack_safety, state);
312 XBT_DEBUG("Back-tracking to depth %d", xbt_fifo_size(mc_stack_safety));
314 MC_replay(mc_stack_safety, pos);
317 xbt_fifo_unshift(mc_stack_safety, state);
318 XBT_DEBUG("Back-tracking to depth %d", xbt_fifo_size(mc_stack_safety));
320 MC_replay(mc_stack_safety, -1);
324 MC_state_delete(state);
330 MC_print_statistics(mc_stats);