Logo AND Algorithmique Numérique Distribuée

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Dumb commit: kill empty line.
[simgrid.git] / src / mc / mc_dpor.c
index a54411d..a97440a 100644 (file)
@@ -1,4 +1,4 @@
-/* Copyright (c) 2008-2012. Da SimGrid Team. 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. */
@@ -9,21 +9,44 @@ XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_dpor, mc,
                                 "Logging specific to MC DPOR exploration");
 
 xbt_dynar_t visited_states;
+xbt_dict_t first_enabled_state;
 
-static int is_visited_state(void);
+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(_surf_mc_visited == 0)
-    return 0;
+  if(_sg_mc_visited == 0)
+    return -1;
 
   int raw_mem_set = (mmalloc_get_current_heap() == raw_heap);
 
   MC_SET_RAW_MEM;
-
-  mc_snapshot_t new_state = NULL;
-  new_state = MC_take_snapshot();  
-
+  mc_visited_state_t new_state = visited_state_new();
   MC_UNSET_RAW_MEM;
   
   if(xbt_dynar_is_empty(visited_states)){
@@ -34,43 +57,121 @@ static int is_visited_state(){
 
     if(raw_mem_set)
       MC_SET_RAW_MEM;
-    return 0;
+
+    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;
-    mc_snapshot_t state_test = NULL;
-     
-    xbt_dynar_foreach(visited_states, cursor, state_test){
-      if(XBT_LOG_ISENABLED(mc_dpor, xbt_log_priority_debug))
-        XBT_DEBUG("****** Pair visited #%d ******", cursor + 1);
-      if(snapshot_compare(new_state, state_test, NULL, NULL) == 0){
-        if(raw_mem_set)
-          MC_SET_RAW_MEM;
-        else
-          MC_UNSET_RAW_MEM;
-        
-        return 1;
-      }   
+    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++;
+            }
+          }   
+        }
+      }
     }
 
-    if(xbt_dynar_length(visited_states) == _surf_mc_visited){
-      mc_snapshot_t state_to_remove = NULL;
-      xbt_dynar_shift(visited_states, &state_to_remove);
-      MC_free_snapshot(state_to_remove);
+    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);
     }
-
-    xbt_dynar_push(visited_states, &new_state); 
     
     MC_UNSET_RAW_MEM;
 
     if(raw_mem_set)
       MC_SET_RAW_MEM;
     
-    return 0;
+    return -1;
     
   }
 }
@@ -90,7 +191,9 @@ void MC_dpor_init()
   MC_SET_RAW_MEM;
 
   initial_state = MC_state_new();
-  visited_states = xbt_dynar_new(sizeof(mc_snapshot_t), NULL);
+  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;
 
@@ -106,12 +209,26 @@ void MC_dpor_init()
   xbt_swag_foreach(process, simix_global->process_list){
     if(MC_process_is_enabled(process)){
       MC_state_interleave_process(initial_state, process);
-      break;
+      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;
 
   if(raw_mem_set)
@@ -130,12 +247,14 @@ void MC_dpor(void)
 {
 
   char *req_str;
-  int value;
-  smx_simcall_t req = NULL, prev_req = NULL;
+  int value, value2;
+  smx_simcall_t req = NULL, prev_req = NULL, req2 = NULL;
+  s_smx_simcall_t req3;
   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;
 
   while (xbt_fifo_size(mc_stack_safety) > 0) {
 
@@ -153,7 +272,7 @@ void MC_dpor(void)
 
     /* If there are processes to interleave and the maximum depth has not been reached
        then perform one step of the exploration algorithm */
-    if (xbt_fifo_size(mc_stack_safety) < _surf_mc_max_depth &&
+    if (xbt_fifo_size(mc_stack_safety) <= _sg_mc_max_depth &&
         (req = MC_state_get_request(state, &value))) {
 
       /* Debug information */
@@ -162,10 +281,20 @@ void MC_dpor(void)
         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++;
 
+      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;
+
+      MC_state_set_executed_request(state, req, value);
+
       /* Answer the request */
       SIMIX_simcall_pre(req, value); /* After this call req is no longer usefull */
 
@@ -177,40 +306,55 @@ void MC_dpor(void)
 
       next_state = MC_state_new();
 
-      if(!is_visited_state()){
+      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((xbt_fifo_size(mc_stack_safety) + 1) != (_surf_mc_max_depth - 1))
+            if(mc_reduce_kind != e_mc_reduce_none)
               break;
           }
         }
 
-        if(_surf_mc_checkpoint && ((xbt_fifo_size(mc_stack_safety) + 1) % _surf_mc_checkpoint == 0)){
+        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{
 
-        XBT_DEBUG("State already visited !");
-        
+        if(dot_output != NULL)
+          fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", state->num, visited_state, req_str);
+
       }
 
       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;
 
-      /* FIXME: 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 {
 
-      if(xbt_fifo_size(mc_stack_safety) == _surf_mc_max_depth)  
+      if(xbt_fifo_size(mc_stack_safety) == _sg_mc_max_depth)  
         XBT_WARN("/!\\ Max depth reached ! /!\\ ");
       else
         XBT_DEBUG("There are no more processes to interleave.");
@@ -236,42 +380,70 @@ void MC_dpor(void)
          state that executed that previous request. */
       
       while ((state = xbt_fifo_shift(mc_stack_safety)) != NULL) {
-        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(mc_reduce_kind != e_mc_reduce_none){
+          req = MC_state_get_internal_request(state);
+          /* If max_depth reached, check only for the last state if the request that has generated
+             it, depends on any other processes still enabled when max_depth reached */
+          if(xbt_fifo_size(mc_stack_safety) == _sg_mc_max_depth - 1){
+            req3 = *req;
+            xbt_swag_foreach(process, simix_global->process_list){
+              if(MC_process_is_enabled(process) && !MC_state_process_is_done(state, process)){
+                MC_state_interleave_process(state, process);
+                req2 = MC_state_get_request(state, &value2);
+                MC_state_set_executed_request(state, req2, value2);
+                req2 = MC_state_get_internal_request(state);
+                if(MC_request_depend(&req3, req2)){
+                  if(XBT_LOG_ISENABLED(mc_dpor, xbt_log_priority_debug)){
+                    XBT_DEBUG("Dependent Transitions:");
+                    req_str = MC_request_to_string(&req3, value);
+                    XBT_DEBUG("%s (state=%p)", req_str, state);
+                    xbt_free(req_str);
+                    req_str = MC_request_to_string(req2, value);
+                    XBT_DEBUG("%s (state=%p)", req_str, state);
+                    xbt_free(req_str);              
+                  } 
+                  MC_state_interleave_process(state, process);
+                  break;
+                }
+              }
             }
+          }
+          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(!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);
+              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;
+              break;
 
-          }else if(req->issuer == MC_state_get_executed_request(prev_state, &value)->issuer){
+            }else if(req->issuer == MC_state_get_internal_request(prev_state)->issuer){
 
-            break;
+              XBT_DEBUG("Simcall %d and %d with same issuer", req->call, MC_state_get_internal_request(prev_state)->call);
+              break;
 
+            }
           }
         }
-
+             
         if (MC_state_interleave_size(state)) {
           /* We found a back-tracking point, let's loop */
-          if(_surf_mc_checkpoint){
+          if(_sg_mc_checkpoint){
             if(state->system_state != NULL){
               MC_restore_snapshot(state->system_state);
               xbt_fifo_unshift(mc_stack_safety, state);
-              XBT_DEBUG("Back-tracking to depth %d", xbt_fifo_size(mc_stack_safety));
               MC_UNSET_RAW_MEM;
             }else{
               pos = xbt_fifo_size(mc_stack_safety);
@@ -287,16 +459,15 @@ void MC_dpor(void)
               }
               MC_restore_snapshot(restore_state->system_state);
               xbt_fifo_unshift(mc_stack_safety, state);
-              XBT_DEBUG("Back-tracking to depth %d", xbt_fifo_size(mc_stack_safety));
               MC_UNSET_RAW_MEM;
               MC_replay(mc_stack_safety, pos);
             }
           }else{
             xbt_fifo_unshift(mc_stack_safety, state);
-            XBT_DEBUG("Back-tracking to depth %d", xbt_fifo_size(mc_stack_safety));
             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(state);