-/* Copyright (c) 2008 Martin Quinson, Cristian Rosa.
- All rights reserved. */
+/* Copyright (c) 2008-2013. Da SimGrid Team. All rights reserved. */
/* This program is free software; you can redistribute it and/or modify it
* under the terms of the license (GNU LGPL) which comes with this package. */
-#include "private.h"
+#include "mc_private.h"
XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_dpor, mc,
- "Logging specific to MC DPOR exploration");
+ "Logging specific to MC DPOR exploration");
+
+xbt_dynar_t visited_states;
+xbt_dict_t first_enabled_state;
+
+static void visited_state_free(mc_visited_state_t state){
+ if(state){
+ MC_free_snapshot(state->system_state);
+ xbt_free(state);
+ }
+}
+
+static void visited_state_free_voidp(void *s){
+ visited_state_free((mc_visited_state_t) * (void **) s);
+}
+
+static mc_visited_state_t visited_state_new(){
+
+ mc_visited_state_t new_state = NULL;
+ new_state = xbt_new0(s_mc_visited_state_t, 1);
+ new_state->heap_bytes_used = mmalloc_get_bytes_used(std_heap);
+ new_state->nb_processes = xbt_swag_size(simix_global->process_list);
+ new_state->system_state = MC_take_snapshot();
+ new_state->num = mc_stats->expanded_states - 1;
+
+ return new_state;
+
+}
+
+/* Dichotomic search in visited_states dynar.
+ * States are ordered by the number of processes then the number of bytes used in std_heap */
+
+static int is_visited_state(){
+
+ if(_sg_mc_visited == 0)
+ return -1;
+
+ int raw_mem_set = (mmalloc_get_current_heap() == raw_heap);
+
+ MC_SET_RAW_MEM;
+ mc_visited_state_t new_state = visited_state_new();
+ MC_UNSET_RAW_MEM;
+
+ if(xbt_dynar_is_empty(visited_states)){
+
+ MC_SET_RAW_MEM;
+ xbt_dynar_push(visited_states, &new_state);
+ MC_UNSET_RAW_MEM;
+
+ if(raw_mem_set)
+ MC_SET_RAW_MEM;
+
+ return -1;
+
+ }else{
+
+ MC_SET_RAW_MEM;
+
+ size_t current_bytes_used = new_state->heap_bytes_used;
+ int current_nb_processes = new_state->nb_processes;
+
+ unsigned int cursor = 0;
+ int previous_cursor = 0, next_cursor = 0;
+ int start = 0;
+ int end = xbt_dynar_length(visited_states) - 1;
+
+ mc_visited_state_t state_test = NULL;
+ size_t bytes_used_test;
+ int nb_processes_test;
+ int same_processes_and_bytes_not_found = 1;
+
+ while(start <= end && same_processes_and_bytes_not_found){
+ cursor = (start + end) / 2;
+ state_test = (mc_visited_state_t)xbt_dynar_get_as(visited_states, cursor, mc_visited_state_t);
+ bytes_used_test = state_test->heap_bytes_used;
+ nb_processes_test = state_test->nb_processes;
+ if(nb_processes_test < current_nb_processes)
+ start = cursor + 1;
+ if(nb_processes_test > current_nb_processes)
+ end = cursor - 1;
+ if(nb_processes_test == current_nb_processes){
+ if(bytes_used_test < current_bytes_used)
+ start = cursor + 1;
+ if(bytes_used_test > current_bytes_used)
+ end = cursor - 1;
+ if(bytes_used_test == current_bytes_used){
+ same_processes_and_bytes_not_found = 0;
+ if(snapshot_compare(new_state->system_state, state_test->system_state) == 0){
+ xbt_dynar_remove_at(visited_states, cursor, NULL);
+ xbt_dynar_insert_at(visited_states, cursor, &new_state);
+ XBT_DEBUG("State %d already visited ! (equal to state %d)", new_state->num, state_test->num);
+ if(raw_mem_set)
+ MC_SET_RAW_MEM;
+ else
+ MC_UNSET_RAW_MEM;
+ return state_test->num;
+ }else{
+ /* Search another state with same number of bytes used in std_heap */
+ previous_cursor = cursor - 1;
+ while(previous_cursor >= 0){
+ state_test = (mc_visited_state_t)xbt_dynar_get_as(visited_states, previous_cursor, mc_visited_state_t);
+ bytes_used_test = state_test->system_state->heap_bytes_used;
+ if(bytes_used_test != current_bytes_used)
+ break;
+ if(snapshot_compare(new_state->system_state, state_test->system_state) == 0){
+ xbt_dynar_remove_at(visited_states, previous_cursor, NULL);
+ xbt_dynar_insert_at(visited_states, previous_cursor, &new_state);
+ XBT_DEBUG("State %d already visited ! (equal to state %d)", new_state->num, state_test->num);
+ if(raw_mem_set)
+ MC_SET_RAW_MEM;
+ else
+ MC_UNSET_RAW_MEM;
+ return state_test->num;
+ }
+ previous_cursor--;
+ }
+ next_cursor = cursor + 1;
+ while(next_cursor < xbt_dynar_length(visited_states)){
+ state_test = (mc_visited_state_t)xbt_dynar_get_as(visited_states, next_cursor, mc_visited_state_t);
+ bytes_used_test = state_test->system_state->heap_bytes_used;
+ if(bytes_used_test != current_bytes_used)
+ break;
+ if(snapshot_compare(new_state->system_state, state_test->system_state) == 0){
+ xbt_dynar_remove_at(visited_states, next_cursor, NULL);
+ xbt_dynar_insert_at(visited_states, next_cursor, &new_state);
+ XBT_DEBUG("State %d already visited ! (equal to state %d)", new_state->num, state_test->num);
+ if(raw_mem_set)
+ MC_SET_RAW_MEM;
+ else
+ MC_UNSET_RAW_MEM;
+ return state_test->num;
+ }
+ next_cursor++;
+ }
+ }
+ }
+ }
+ }
+
+ state_test = (mc_visited_state_t)xbt_dynar_get_as(visited_states, cursor, mc_visited_state_t);
+ bytes_used_test = state_test->heap_bytes_used;
+
+ if(bytes_used_test < current_bytes_used)
+ xbt_dynar_insert_at(visited_states, cursor + 1, &new_state);
+ else
+ xbt_dynar_insert_at(visited_states, cursor, &new_state);
+
+ if(xbt_dynar_length(visited_states) > _sg_mc_visited){
+ int min = mc_stats->expanded_states;
+ unsigned int cursor2 = 0;
+ unsigned int index = 0;
+ xbt_dynar_foreach(visited_states, cursor2, state_test){
+ if(state_test->num < min){
+ index = cursor2;
+ min = state_test->num;
+ }
+ }
+ xbt_dynar_remove_at(visited_states, index, NULL);
+ }
+
+ MC_UNSET_RAW_MEM;
+
+ if(raw_mem_set)
+ MC_SET_RAW_MEM;
+
+ return -1;
+
+ }
+}
/**
* \brief Initialize the DPOR exploration algorithm
*/
void MC_dpor_init()
{
+
+ int raw_mem_set = (mmalloc_get_current_heap() == raw_heap);
+
mc_state_t initial_state = NULL;
- mc_transition_t trans, trans_tmp = NULL;
- xbt_setset_cursor_t cursor = NULL;
+ smx_process_t process;
/* Create the initial state and push it into the exploration stack */
MC_SET_RAW_MEM;
+
initial_state = MC_state_new();
- xbt_fifo_unshift(mc_stack, initial_state);
+ visited_states = xbt_dynar_new(sizeof(mc_visited_state_t), visited_state_free_voidp);
+
+ first_enabled_state = xbt_dict_new_homogeneous(&xbt_free_f);
+
MC_UNSET_RAW_MEM;
- /* Schedule all the processes to detect the transitions of the initial state */
- DEBUG0("**************************************************");
- DEBUG0("Initial state");
+ XBT_DEBUG("**************************************************");
+ XBT_DEBUG("Initial state");
- while(xbt_swag_size(simix_global->process_to_run)){
- MC_schedule_enabled_processes();
- MC_execute_surf_actions();
- }
+ /* Wait for requests (schedules processes) */
+ MC_wait_for_requests();
MC_SET_RAW_MEM;
- MC_trans_compute_enabled(initial_state->enabled_transitions,
- initial_state->transitions);
-
- /* Fill the interleave set of the initial state with an enabled process */
- trans = xbt_setset_set_choose(initial_state->enabled_transitions);
- if(trans){
- DEBUG1("Choosing process %s for next interleave", trans->process->name);
- xbt_setset_foreach(initial_state->enabled_transitions, cursor, trans_tmp){
- if(trans_tmp->process == trans->process)
- xbt_setset_set_insert(initial_state->interleave, trans_tmp);
+
+ /* Get an enabled process and insert it in the interleave set of the initial state */
+ xbt_swag_foreach(process, simix_global->process_list){
+ if(MC_process_is_enabled(process)){
+ MC_state_interleave_process(initial_state, process);
+ if(mc_reduce_kind != e_mc_reduce_none)
+ break;
}
}
+
+ xbt_fifo_unshift(mc_stack_safety, initial_state);
+
+ /* To ensure the soundness of DPOR, we have to keep a list of
+ processes which are still enabled at each step of the exploration.
+ If max depth is reached, we interleave them in the state in which they have
+ been enabled for the first time. */
+ xbt_swag_foreach(process, simix_global->process_list){
+ if(MC_process_is_enabled(process)){
+ char *key = bprintf("%lu", process->pid);
+ char *data = bprintf("%d", xbt_fifo_size(mc_stack_safety));
+ xbt_dict_set(first_enabled_state, key, data, NULL);
+ xbt_free(key);
+ }
+ }
+
MC_UNSET_RAW_MEM;
- /* Update Statistics */
- mc_stats->state_size += xbt_setset_set_size(initial_state->enabled_transitions);
+ if(raw_mem_set)
+ MC_SET_RAW_MEM;
+ else
+ MC_UNSET_RAW_MEM;
+
}
/**
- * \brief Perform the model-checking operation using a depth-first search exploration
+ * \brief Perform the model-checking operation using a depth-first search exploration
* with Dynamic Partial Order Reductions
*/
void MC_dpor(void)
{
- mc_transition_t trans, trans_tmp = NULL;
- mc_state_t next_state = NULL;
- xbt_setset_cursor_t cursor = NULL;
-
- while(xbt_fifo_size(mc_stack) > 0){
-
- DEBUG0("**************************************************");
- /* FIXME: Think about what happen if there are no transitions but there are
- some actions on the models. (ex. all the processes do a sleep(0) in a round). */
+ char *req_str;
+ int value;
+ smx_simcall_t req = NULL, prev_req = NULL;
+ mc_state_t state = NULL, prev_state = NULL, next_state = NULL, restore_state=NULL;
+ smx_process_t process = NULL;
+ xbt_fifo_item_t item = NULL;
+ int pos;
+ int visited_state;
+ int max_depth_reached = 0;
+
+ while (xbt_fifo_size(mc_stack_safety) > 0) {
/* Get current state */
- mc_current_state = (mc_state_t) xbt_fifo_get_item_content(xbt_fifo_get_first_item(mc_stack));
-
- /* If there are transitions to execute and the maximun depth has not been reached
+ state = (mc_state_t)
+ xbt_fifo_get_item_content(xbt_fifo_get_first_item(mc_stack_safety));
+
+ XBT_DEBUG("**************************************************");
+ XBT_DEBUG("Exploration depth=%d (state=%p)(%u interleave)",
+ xbt_fifo_size(mc_stack_safety), state,
+ MC_state_interleave_size(state));
+
+ /* Update statistics */
+ mc_stats->visited_states++;
+
+ /* If there are processes to interleave and the maximum depth has not been reached
then perform one step of the exploration algorithm */
- if(xbt_setset_set_size(mc_current_state->interleave) > 0 && xbt_fifo_size(mc_stack) < MAX_DEPTH){
+ if (xbt_fifo_size(mc_stack_safety) <= _sg_mc_max_depth &&
+ (req = MC_state_get_request(state, &value))) {
- DEBUG4("Exploration detph=%d (state=%p)(%d interleave) (%d enabled)", xbt_fifo_size(mc_stack),
- mc_current_state, xbt_setset_set_size(mc_current_state->interleave),
- xbt_setset_set_size(mc_current_state->enabled_transitions));
-
- /* Update statistics */
- mc_stats->visited_states++;
+ /* Debug information */
+ if(XBT_LOG_ISENABLED(mc_dpor, xbt_log_priority_debug)){
+ req_str = MC_request_to_string(req, value);
+ XBT_DEBUG("Execute: %s", req_str);
+ xbt_free(req_str);
+ }
+
+ req_str = MC_request_get_dot_output(req, value);
+
+ MC_state_set_executed_request(state, req, value);
mc_stats->executed_transitions++;
-
- /* Choose a transition to execute from the interleave set of the current
- state, and create the data structures for the new expanded state in the
- exploration stack. */
- MC_SET_RAW_MEM;
- trans = xbt_setset_set_extract(mc_current_state->interleave);
- /* Add the transition in the done set of the current state */
- xbt_setset_set_insert(mc_current_state->done, trans);
-
- next_state = MC_state_new();
- xbt_fifo_unshift(mc_stack, next_state);
-
- /* Set it as the executed transition of the current state */
- mc_current_state->executed_transition = trans;
+ MC_SET_RAW_MEM;
+ char *key = bprintf("%lu", req->issuer->pid);
+ xbt_dict_remove(first_enabled_state, key);
+ xbt_free(key);
MC_UNSET_RAW_MEM;
- /* Execute the selected transition by scheduling it's associated process.
- Then schedule every process that got ready to run due to the execution
- of the transition */
- DEBUG1("Executing transition %s", trans->name);
- SIMIX_process_schedule(trans->process);
- MC_execute_surf_actions();
-
- while(xbt_swag_size(simix_global->process_to_run)){
- MC_schedule_enabled_processes();
- MC_execute_surf_actions();
- }
-
- /* Calculate the enabled transitions set of the next state */
+ /* Answer the request */
+ SIMIX_simcall_pre(req, value); /* After this call req is no longer usefull */
+
+ /* Wait for requests (schedules processes) */
+ MC_wait_for_requests();
+
+ /* Create the new expanded state */
MC_SET_RAW_MEM;
- xbt_setset_foreach(mc_current_state->transitions, cursor, trans_tmp){
- if(trans_tmp->process != trans->process){
- xbt_setset_set_insert(next_state->transitions, trans_tmp);
+ next_state = MC_state_new();
+
+ if((visited_state = is_visited_state()) == -1){
+
+ /* Get an enabled process and insert it in the interleave set of the next state */
+ xbt_swag_foreach(process, simix_global->process_list){
+ if(MC_process_is_enabled(process)){
+ MC_state_interleave_process(next_state, process);
+ if(mc_reduce_kind != e_mc_reduce_none)
+ break;
+ }
}
+
+ if(_sg_mc_checkpoint && ((xbt_fifo_size(mc_stack_safety) + 1) % _sg_mc_checkpoint == 0)){
+ next_state->system_state = MC_take_snapshot();
+ }
+
+ if(dot_output != NULL)
+ fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", state->num, next_state->num, req_str);
+
+ }else{
+
+ if(dot_output != NULL)
+ fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", state->num, visited_state, req_str);
+
}
-
- MC_trans_compute_enabled(next_state->enabled_transitions, next_state->transitions);
-
- /* Choose one transition to interleave from the enabled transition set */
- trans = xbt_setset_set_choose(next_state->enabled_transitions);
- if(trans){
- DEBUG1("Choosing process %s for next interleave", trans->process->name);
- xbt_setset_foreach(next_state->enabled_transitions, cursor, trans_tmp){
- if(trans_tmp->process == trans->process)
- xbt_setset_set_insert(next_state->interleave, trans_tmp);
+
+ xbt_fifo_unshift(mc_stack_safety, next_state);
+
+ /* Insert in dict all enabled processes, if not included yet */
+ xbt_swag_foreach(process, simix_global->process_list){
+ if(MC_process_is_enabled(process)){
+ char *key = bprintf("%lu", process->pid);
+ if(xbt_dict_get_or_null(first_enabled_state, key) == NULL){
+ char *data = bprintf("%d", xbt_fifo_size(mc_stack_safety));
+ xbt_dict_set(first_enabled_state, key, data, NULL);
+ }
+ xbt_free(key);
}
}
+
MC_UNSET_RAW_MEM;
- /* Update Statistics */
- mc_stats->state_size += xbt_setset_set_size(next_state->enabled_transitions);
+ xbt_free(req_str);
/* Let's loop again */
-
- /* The interleave set is empty or the maximum depth is reached, let's back-track */
- }else{
- DEBUG0("There are no more transitions to interleave.");
-
- /* Check for deadlocks */
- xbt_setset_substract(mc_current_state->transitions, mc_current_state->done);
- if(xbt_setset_set_size(mc_current_state->transitions) > 0){
- INFO0("**************************");
- INFO0("*** DEAD-LOCK DETECTED ***");
- INFO0("**************************");
- INFO0("Locked transitions:");
- xbt_setset_foreach(mc_current_state->transitions, cursor, trans){
- INFO1("%s", trans->name);
+ /* The interleave set is empty or the maximum depth is reached, let's back-track */
+ } else {
+
+ if(xbt_fifo_size(mc_stack_safety) > _sg_mc_max_depth){
+
+ XBT_WARN("/!\\ Max depth reached ! /!\\ ");
+
+ /* Interleave enabled processes in the state in which they have been enabled for the first time */
+ xbt_swag_foreach(process, simix_global->process_list){
+ if(MC_process_is_enabled(process)){
+ char *key = bprintf("%lu", process->pid);
+ enabled = (int)strtoul(xbt_dict_get_or_null(first_enabled_state, key), 0, 10);
+ xbt_free(key);
+ mc_state_t state_test = NULL;
+ xbt_fifo_item_t item = NULL;
+ int cursor = xbt_fifo_size(mc_stack_safety);
+ xbt_fifo_foreach(mc_stack_safety, item, state_test, mc_state_t){
+ if(cursor-- == enabled){
+ if(!MC_state_process_is_done(state_test, process)){
+ MC_state_interleave_process(state_test, process);
+ break;
+ }
+ }
+ }
+ }
}
- INFO0("Counter-example execution trace:");
- MC_dump_stack(mc_stack);
-
- MC_print_statistics(mc_stats);
- xbt_abort();
+ max_depth_reached = 1;
+
+ }else{
+
+ XBT_DEBUG("There are no more processes to interleave.");
+
+ /* Trash the current state, no longer needed */
+ MC_SET_RAW_MEM;
+ xbt_fifo_shift(mc_stack_safety);
+ MC_state_delete(state);
+ MC_UNSET_RAW_MEM;
+
+ max_depth_reached = 0;
}
-
- mc_transition_t q = NULL;
- xbt_fifo_item_t item = NULL;
- mc_state_t state = NULL;
- //MC_show_stack(mc_stack);
-
- /* Trash the current state, no longer needed */
+ /* Check for deadlocks */
+ if(MC_deadlock_check()){
+ MC_show_deadlock(NULL);
+ return;
+ }
+
MC_SET_RAW_MEM;
- xbt_fifo_shift(mc_stack);
- MC_state_delete(mc_current_state);
-
/* Traverse the stack backwards until a state with a non empty interleave
set is found, deleting all the states that have it empty in the way.
- For each deleted state, check if the transition that has generated it
- (from it's predecesor state), depends on any other previous transition
+ For each deleted state, check if the request that has generated it
+ (from it's predecesor state), depends on any other previous request
executed before it. If it does then add it to the interleave set of the
- state that executed that previous transition. */
- while((mc_current_state = xbt_fifo_shift(mc_stack)) != NULL){
- q = mc_current_state->executed_transition;
- xbt_fifo_foreach(mc_stack, item, state, mc_state_t){
- if(MC_transition_depend(q, state->executed_transition)){
- DEBUG3("Dependence found at state %p (%p,%p)", state, state->executed_transition, q);
- xbt_setset_foreach(state->enabled_transitions, cursor, trans){
- if((trans->process == q->process) && !xbt_setset_set_belongs(state->done, trans)){
- DEBUG2("Unexplored interleaving found at state %p (%p)", state, trans);
-
- xbt_setset_foreach(state->enabled_transitions, cursor, trans){
- if(trans->process == q->process)
- xbt_setset_set_insert(state->interleave, trans);
- }
- /* FIXME: hack to make it work*/
- trans = q;
- break;
+ state that executed that previous request. */
+
+ while ((state = xbt_fifo_shift(mc_stack_safety)) != NULL) {
+ if(mc_reduce_kind != e_mc_reduce_none){
+ if((xbt_fifo_size(mc_stack_safety) == _sg_mc_max_depth) && max_depth_reached){
+ req = MC_state_get_request(state, &value);
+ MC_state_set_executed_request(state, req, value);
+ }
+ req = MC_state_get_internal_request(state);
+ xbt_fifo_foreach(mc_stack_safety, item, prev_state, mc_state_t) {
+ if(MC_request_depend(req, MC_state_get_internal_request(prev_state))){
+ if(XBT_LOG_ISENABLED(mc_dpor, xbt_log_priority_debug)){
+ XBT_DEBUG("Dependent Transitions:");
+ prev_req = MC_state_get_executed_request(prev_state, &value);
+ req_str = MC_request_to_string(prev_req, value);
+ XBT_DEBUG("%s (state=%p)", req_str, prev_state);
+ xbt_free(req_str);
+ prev_req = MC_state_get_executed_request(state, &value);
+ req_str = MC_request_to_string(prev_req, value);
+ XBT_DEBUG("%s (state=%p)", req_str, state);
+ xbt_free(req_str);
}
- }
- if(trans)
+
+ if(!MC_state_process_is_done(prev_state, req->issuer))
+ MC_state_interleave_process(prev_state, req->issuer);
+ else
+ XBT_DEBUG("Process %p is in done set", req->issuer);
+
break;
+
+ }else if(req->issuer == MC_state_get_internal_request(prev_state)->issuer){
+
+ XBT_DEBUG("Simcall %d and %d with same issuer", req->call, MC_state_get_internal_request(prev_state)->call);
+ break;
+
+ }
}
}
- if(xbt_setset_set_size(mc_current_state->interleave) > 0){
+
+ if (MC_state_interleave_size(state) && xbt_fifo_size(mc_stack_safety) < _sg_mc_max_depth) {
/* We found a back-tracking point, let's loop */
- xbt_fifo_unshift(mc_stack, mc_current_state);
- DEBUG1("Back-tracking to depth %d", xbt_fifo_size(mc_stack));
- MC_replay(mc_stack);
- MC_UNSET_RAW_MEM;
+ XBT_DEBUG("Back-tracking to depth %d", xbt_fifo_size(mc_stack_safety) + 1);
+ if(_sg_mc_checkpoint){
+ if(state->system_state != NULL){
+ MC_restore_snapshot(state->system_state);
+ xbt_fifo_unshift(mc_stack_safety, state);
+ MC_UNSET_RAW_MEM;
+ }else{
+ pos = xbt_fifo_size(mc_stack_safety);
+ item = xbt_fifo_get_first_item(mc_stack_safety);
+ while(pos>0){
+ restore_state = (mc_state_t) xbt_fifo_get_item_content(item);
+ if(restore_state->system_state != NULL){
+ break;
+ }else{
+ item = xbt_fifo_get_next_item(item);
+ pos--;
+ }
+ }
+ MC_restore_snapshot(restore_state->system_state);
+ xbt_fifo_unshift(mc_stack_safety, state);
+ MC_UNSET_RAW_MEM;
+ MC_replay(mc_stack_safety, pos);
+ }
+ }else{
+ xbt_fifo_unshift(mc_stack_safety, state);
+ MC_UNSET_RAW_MEM;
+ MC_replay(mc_stack_safety, -1);
+ }
+ XBT_DEBUG("Back-tracking to depth %d", xbt_fifo_size(mc_stack_safety));
break;
- }else{
- MC_state_delete(mc_current_state);
- }
+ } else {
+ MC_state_delete(state);
+ }
}
+ MC_UNSET_RAW_MEM;
}
}
- DEBUG0("We are done");
- /* We are done, show the statistics and return */
MC_print_statistics(mc_stats);
-}
\ No newline at end of file
+ MC_UNSET_RAW_MEM;
+
+ return;
+}
+
+
+
+
