1 /* Copyright (c) 2008 Martin Quinson, Cristian Rosa.
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. */
9 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_dpor, mc,
10 "Logging specific to MC DPOR exploration");
13 * \brief Initialize the DPOR exploration algorithm
17 mc_state_t initial_state = NULL;
18 smx_process_t process;
20 /* Create the initial state and push it into the exploration stack */
22 initial_state = MC_state_new();
23 xbt_fifo_unshift(mc_stack, initial_state);
26 XBT_DEBUG("**************************************************");
27 XBT_DEBUG("Initial state");
29 /* Wait for requests (schedules processes) */
30 MC_wait_for_requests();
33 /* Get an enabled process and insert it in the interleave set of the initial state */
34 xbt_swag_foreach(process, simix_global->process_list){
35 if(MC_process_is_enabled(process)){
36 MC_state_interleave_process(initial_state, process);
42 /* FIXME: Update Statistics
43 mc_stats->state_size +=
44 xbt_setset_set_size(initial_state->enabled_transitions); */
49 * \brief Perform the model-checking operation using a depth-first search exploration
50 * with Dynamic Partial Order Reductions
56 smx_req_t req = NULL, prev_req = NULL;
57 mc_state_t state = NULL, prev_state = NULL, next_state = NULL;
58 smx_process_t process = NULL;
59 xbt_fifo_item_t item = NULL;
61 while (xbt_fifo_size(mc_stack) > 0) {
63 /* Get current state */
65 xbt_fifo_get_item_content(xbt_fifo_get_first_item(mc_stack));
67 XBT_DEBUG("**************************************************");
68 XBT_DEBUG("Exploration detph=%d (state=%p)(%u interleave)",
69 xbt_fifo_size(mc_stack), state,
70 MC_state_interleave_size(state));
72 /* Update statistics */
73 mc_stats->visited_states++;
75 /* If there are processes to interleave and the maximum depth has not been reached
76 then perform one step of the exploration algorithm */
77 if (xbt_fifo_size(mc_stack) < MAX_DEPTH &&
78 (req = MC_state_get_request(state, &value))) {
80 /* Debug information */
81 if(XBT_LOG_ISENABLED(mc_dpor, xbt_log_priority_debug)){
82 req_str = MC_request_to_string(req, value);
83 XBT_DEBUG("Execute: %s", req_str);
87 MC_state_set_executed_request(state, req, value);
88 mc_stats->executed_transitions++;
90 /* Answer the request */
91 SIMIX_request_pre(req, value); /* After this call req is no longer usefull */
93 /* Wait for requests (schedules processes) */
94 MC_wait_for_requests();
96 /* Create the new expanded state */
98 next_state = MC_state_new();
99 xbt_fifo_unshift(mc_stack, next_state);
101 /* Get an enabled process and insert it in the interleave set of the next state */
102 xbt_swag_foreach(process, simix_global->process_list){
103 if(MC_process_is_enabled(process)){
104 MC_state_interleave_process(next_state, process);
110 /* FIXME: Update Statistics
111 mc_stats->state_size +=
112 xbt_setset_set_size(next_state->enabled_transitions);*/
114 /* Let's loop again */
116 /* The interleave set is empty or the maximum depth is reached, let's back-track */
118 XBT_DEBUG("There are no more processes to interleave.");
120 /* Trash the current state, no longer needed */
122 xbt_fifo_shift(mc_stack);
123 MC_state_delete(state);
126 /* Check for deadlocks */
127 if(MC_deadlock_check()){
128 MC_show_deadlock(NULL);
133 /* Traverse the stack backwards until a state with a non empty interleave
134 set is found, deleting all the states that have it empty in the way.
135 For each deleted state, check if the request that has generated it
136 (from it's predecesor state), depends on any other previous request
137 executed before it. If it does then add it to the interleave set of the
138 state that executed that previous request. */
139 while ((state = xbt_fifo_shift(mc_stack)) != NULL) {
140 req = MC_state_get_internal_request(state);
141 xbt_fifo_foreach(mc_stack, item, prev_state, mc_state_t) {
142 if(MC_request_depend(req, MC_state_get_internal_request(prev_state))){
143 if(XBT_LOG_ISENABLED(mc_dpor, xbt_log_priority_debug)){
144 XBT_DEBUG("Dependent Transitions:");
145 prev_req = MC_state_get_executed_request(prev_state, &value);
146 req_str = MC_request_to_string(prev_req, value);
147 XBT_DEBUG("%s (state=%p)", req_str, prev_state);
149 prev_req = MC_state_get_executed_request(state, &value);
150 req_str = MC_request_to_string(prev_req, value);
151 XBT_DEBUG("%s (state=%p)", req_str, state);
155 if(!MC_state_process_is_done(prev_state, req->issuer))
156 MC_state_interleave_process(prev_state, req->issuer);
158 XBT_DEBUG("Process %p is in done set", req->issuer);
163 if (MC_state_interleave_size(state)) {
164 /* We found a back-tracking point, let's loop */
165 xbt_fifo_unshift(mc_stack, state);
166 XBT_DEBUG("Back-tracking to depth %d", xbt_fifo_size(mc_stack));
171 MC_state_delete(state);