X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/dccf1b41e9c7b5a696f01abceaa2779fe65f154f..f601750c63a340979328ed9817fe225c5ce43959:/src/surf/maxmin.cpp

diff --git a/src/surf/maxmin.cpp b/src/surf/maxmin.cpp
index 623a3b28f5..5876ad7d40 100644
--- a/src/surf/maxmin.cpp
+++ b/src/surf/maxmin.cpp
@@ -1,19 +1,20 @@
-/* Copyright (c) 2004-2015. The SimGrid Team.
- * All rights reserved.                                                     */
+/* Copyright (c) 2004-2017. The 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. */
 
 /* \file callbacks.h */
 
-#include "xbt/sysdep.h"
+#include "maxmin_private.hpp"
 #include "xbt/log.h"
-#include "xbt/strbuff.h"
 #include "xbt/mallocator.h"
-#include "maxmin_private.hpp"
-#include <stdlib.h>
-#include <stdio.h>              /* sprintf */
+#include "xbt/sysdep.h"
+#include <cxxabi.h>
+#include <limits>
 #include <math.h>
+#include <stdio.h> /* sprintf */
+#include <stdlib.h>
+
 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(surf_maxmin, surf, "Logging specific to SURF (maxmin)");
 
 typedef struct s_dyn_light {
@@ -22,9 +23,9 @@ typedef struct s_dyn_light {
   int size;
 } s_dyn_light_t, *dyn_light_t;
 
-double sg_maxmin_precision = 0.00001;
-double sg_surf_precision   = 0.00001;
-int    sg_concurrency_limit= 100;
+double sg_maxmin_precision = 0.00001; /* Change this with --cfg=maxmin/precision:VALUE */
+double sg_surf_precision   = 0.00001; /* Change this with --cfg=surf/precision:VALUE */
+int sg_concurrency_limit   = -1;      /* Change this with --cfg=maxmin/concurrency-limit:VALUE */
 
 static void *lmm_variable_mallocator_new_f();
 static void lmm_variable_mallocator_free_f(void *var);
@@ -112,11 +113,16 @@ void lmm_system_free(lmm_system_t sys)
   lmm_variable_t var = nullptr;
   lmm_constraint_t cnst = nullptr;
 
-  if (!sys)
+  if (sys == nullptr)
     return;
 
   while ((var = (lmm_variable_t) extract_variable(sys))) {
-    XBT_WARN("Variable %d still in system when freing it: this may be a bug", var->id_int);
+    int status;
+    char* demangled = abi::__cxa_demangle(typeid(*var->id).name(), 0, 0, &status);
+
+    XBT_WARN("Probable bug: a %s variable (#%d) not removed before the LMM system destruction.", demangled,
+             var->id_int);
+    xbt_free(demangled);
     lmm_var_free(sys, var);
   }
   while ((cnst = (lmm_constraint_t) extract_constraint(sys)))
@@ -129,7 +135,6 @@ void lmm_system_free(lmm_system_t sys)
 static inline void lmm_variable_remove(lmm_system_t sys, lmm_variable_t var)
 {
   int i;
-  int nelements;
 
   lmm_element_t elem = nullptr;
 
@@ -148,9 +153,9 @@ static inline void lmm_variable_remove(lmm_system_t sys, lmm_variable_t var)
     xbt_swag_remove(elem, &(elem->constraint->enabled_element_set));
     xbt_swag_remove(elem, &(elem->constraint->disabled_element_set));
     xbt_swag_remove(elem, &(elem->constraint->active_element_set));
-    nelements=xbt_swag_size(&(elem->constraint->enabled_element_set)) +
-              xbt_swag_size(&(elem->constraint->disabled_element_set));
-    if (!nelements)
+    int nelements = xbt_swag_size(&(elem->constraint->enabled_element_set)) +
+                    xbt_swag_size(&(elem->constraint->disabled_element_set));
+    if (nelements == 0)
       make_constraint_inactive(sys, elem->constraint);
     else
       lmm_on_disabled_var(sys,elem->constraint);
@@ -198,7 +203,7 @@ lmm_constraint_t lmm_constraint_new(lmm_system_t sys, void *id, double bound_val
   cnst->bound = bound_value;
   cnst->concurrency_maximum=0;
   cnst->concurrency_current=0;
-  cnst->concurrency_limit=sg_concurrency_limit;
+  cnst->concurrency_limit  = sg_concurrency_limit;
   cnst->usage = 0;
   cnst->sharing_policy = 1; /* FIXME: don't hardcode the value */
   insert_constraint(sys, cnst);
@@ -242,16 +247,17 @@ int lmm_constraint_sharing_policy(lmm_constraint_t cnst)
   return (cnst->sharing_policy);
 }
 
-/* @brief Remove a constraint 
+/* @brief Remove a constraint
  * Currently this is dead code, but it is exposed in maxmin.h
- * Apparently, this call was designed assuming that constraint would no more have elements in it. 
+ * Apparently, this call was designed assuming that constraint would no more have elements in it.
  * If not the case, assertion will fail, and you need to add calls e.g. to lmm_shrink before effectively removing it.
  */
 inline void lmm_constraint_free(lmm_system_t sys,lmm_constraint_t cnst)
 {
-  xbt_assert(!xbt_swag_size(&(cnst->active_element_set)),"Removing constraint but it still has active elements");
-  xbt_assert(!xbt_swag_size(&(cnst->enabled_element_set)),"Removing constraint but it still has enabled elements");
-  xbt_assert(!xbt_swag_size(&(cnst->disabled_element_set)),"Removing constraint but it still has disabled elements");
+  xbt_assert(not xbt_swag_size(&(cnst->active_element_set)), "Removing constraint but it still has active elements");
+  xbt_assert(not xbt_swag_size(&(cnst->enabled_element_set)), "Removing constraint but it still has enabled elements");
+  xbt_assert(not xbt_swag_size(&(cnst->disabled_element_set)),
+             "Removing constraint but it still has disabled elements");
   remove_constraint(sys, cnst);
   lmm_cnst_free(sys, cnst);
 }
@@ -269,7 +275,8 @@ static void lmm_variable_mallocator_free_f(void *var)
   xbt_free(var);
 }
 
-lmm_variable_t lmm_variable_new(lmm_system_t sys, void *id, double weight, double bound, int number_of_constraints)
+lmm_variable_t lmm_variable_new(lmm_system_t sys, simgrid::surf::Action* id, double weight, double bound,
+                                int number_of_constraints)
 {
   lmm_variable_t var = nullptr;
   int i;
@@ -354,7 +361,7 @@ void lmm_shrink(lmm_system_t sys, lmm_constraint_t cnst, lmm_variable_t var)
     }
   }
 
-  if (!found) {
+  if (not found) {
     XBT_DEBUG("cnst %p is not found in var %p", cnst, var);
     return;
   }
@@ -387,7 +394,7 @@ void lmm_shrink(lmm_system_t sys, lmm_constraint_t cnst, lmm_variable_t var)
     make_constraint_inactive(sys, cnst);
   else {
     //Check maxconcurrency to see if we can enable new variables
-    lmm_on_disabled_var(sys,elem->constraint);       
+    lmm_on_disabled_var(sys,elem->constraint);
   }
 
   lmm_check_concurrency(sys);
@@ -396,7 +403,6 @@ void lmm_shrink(lmm_system_t sys, lmm_constraint_t cnst, lmm_variable_t var)
 void lmm_expand(lmm_system_t sys, lmm_constraint_t cnst, lmm_variable_t var, double value)
 {
   lmm_element_t elem = nullptr;
-  double weight;
   int i,current_share;
 
   sys->modified = 1;
@@ -412,15 +418,15 @@ void lmm_expand(lmm_system_t sys, lmm_constraint_t cnst, lmm_variable_t var, dou
     }
   }
 
-  //Check if we need to disable the variable 
+  //Check if we need to disable the variable
   if(var->weight>0 && var->concurrency_share-current_share>lmm_concurrency_slack(cnst)) {
-    weight=var->weight;
+    double weight = var->weight;
     lmm_disable_var(sys,var);
     for (i = 0; i < var->cnsts_number; i++)
       lmm_on_disabled_var(sys,var->cnsts[i].constraint);
     value=0;
     var->staged_weight=weight;
-    xbt_assert(!var->weight);
+    xbt_assert(not var->weight);
   }
 
   xbt_assert(var->cnsts_number < var->cnsts_size, "Too much constraints");
@@ -437,7 +443,7 @@ void lmm_expand(lmm_system_t sys, lmm_constraint_t cnst, lmm_variable_t var, dou
   } else
     xbt_swag_insert_at_tail(elem, &(elem->constraint->disabled_element_set));
 
-  if(!sys->selective_update_active) {
+  if (not sys->selective_update_active) {
     make_constraint_active(sys, cnst);
   } else if(elem->value>0 || var->weight >0) {
     make_constraint_active(sys, cnst);
@@ -452,7 +458,7 @@ void lmm_expand(lmm_system_t sys, lmm_constraint_t cnst, lmm_variable_t var, dou
 
 void lmm_expand_add(lmm_system_t sys, lmm_constraint_t cnst, lmm_variable_t var, double value)
 {
-  int i,j;
+  int i;
   double weight;
   sys->modified = 1;
 
@@ -477,10 +483,10 @@ void lmm_expand_add(lmm_system_t sys, lmm_constraint_t cnst, lmm_variable_t var,
       if(lmm_concurrency_slack(cnst)<lmm_element_concurrency(&var->cnsts[i])){
         weight=var->weight;
         lmm_disable_var(sys,var);
-        for (j = 0; j < var->cnsts_number; j++)
+        for (int j = 0; j < var->cnsts_number; j++)
           lmm_on_disabled_var(sys,var->cnsts[j].constraint);
         var->staged_weight=weight;
-        xbt_assert(!var->weight);
+        xbt_assert(not var->weight);
       }
       lmm_increase_concurrency(&var->cnsts[i]);
     }
@@ -514,21 +520,21 @@ int lmm_get_number_of_cnst_from_var(lmm_system_t /*sys*/, lmm_variable_t var)
 
 lmm_variable_t lmm_get_var_from_cnst(lmm_system_t /*sys*/, lmm_constraint_t cnst, lmm_element_t * elem)
 {
-  if (!(*elem)) {
+  if (*elem == nullptr) {
     // That is the first call, pick the first element among enabled_element_set (or disabled_element_set if
     // enabled_element_set is empty)
     *elem = (lmm_element_t) xbt_swag_getFirst(&(cnst->enabled_element_set));
-    if (!(*elem))
+    if (*elem == nullptr)
       *elem = (lmm_element_t) xbt_swag_getFirst(&(cnst->disabled_element_set));
   } else {
     //elem is not null, so we carry on
     if(xbt_swag_belongs(*elem,&(cnst->enabled_element_set))){
       //Look at enabled_element_set, and jump to disabled_element_set when finished
       *elem = (lmm_element_t) xbt_swag_getNext(*elem, cnst->enabled_element_set.offset);
-      if (!(*elem))
+      if (*elem == nullptr)
         *elem = (lmm_element_t) xbt_swag_getFirst(&(cnst->disabled_element_set));
     } else {
-      *elem = (lmm_element_t) xbt_swag_getNext(*elem, cnst->disabled_element_set.offset);      
+      *elem = (lmm_element_t) xbt_swag_getNext(*elem, cnst->disabled_element_set.offset);
     }
   }
   if (*elem)
@@ -542,10 +548,10 @@ lmm_variable_t lmm_get_var_from_cnst(lmm_system_t /*sys*/, lmm_constraint_t cnst
 lmm_variable_t lmm_get_var_from_cnst_safe(lmm_system_t /*sys*/, lmm_constraint_t cnst, lmm_element_t * elem,
                                           lmm_element_t * nextelem, int * numelem)
 {
-  if (!(*elem)){
+  if (*elem == nullptr) {
     *elem = (lmm_element_t) xbt_swag_getFirst(&(cnst->enabled_element_set));
     *numelem = xbt_swag_size(&(cnst->enabled_element_set))+xbt_swag_size(&(cnst->disabled_element_set))-1;
-    if (!(*elem))
+    if (*elem == nullptr)
       *elem = (lmm_element_t) xbt_swag_getFirst(&(cnst->disabled_element_set));
   }else{
     *elem = *nextelem;
@@ -559,10 +565,10 @@ lmm_variable_t lmm_get_var_from_cnst_safe(lmm_system_t /*sys*/, lmm_constraint_t
     if(xbt_swag_belongs(*elem,&(cnst->enabled_element_set))){
       //Look at enabled_element_set, and jump to disabled_element_set when finished
       *nextelem = (lmm_element_t) xbt_swag_getNext(*elem, cnst->enabled_element_set.offset);
-      if (!(*nextelem))
+      if (*nextelem == nullptr)
         *nextelem = (lmm_element_t) xbt_swag_getFirst(&(cnst->disabled_element_set));
     } else {
-      *nextelem = (lmm_element_t) xbt_swag_getNext(*elem, cnst->disabled_element_set.offset);      
+      *nextelem = (lmm_element_t) xbt_swag_getNext(*elem, cnst->disabled_element_set.offset);
     }
     return (*elem)->variable;
   }else
@@ -603,7 +609,7 @@ static inline void saturated_constraint_set_update(double usage, int cnst_light_
 static inline void saturated_variable_set_update(s_lmm_constraint_light_t *cnst_light_tab,
                                                  dyn_light_t saturated_constraint_set, lmm_system_t sys)
 {
-  /* Add active variables (i.e. variables that need to be set) from the set of constraints to saturate (cnst_light_tab)*/ 
+  /* Add active variables (i.e. variables that need to be set) from the set of constraints to saturate (cnst_light_tab)*/
   lmm_constraint_light_t cnst = nullptr;
   void *_elem;
   lmm_element_t elem = nullptr;
@@ -624,69 +630,69 @@ static inline void saturated_variable_set_update(s_lmm_constraint_light_t *cnst_
 
 void lmm_print(lmm_system_t sys)
 {
-  void *_cnst, *_elem, *_var;
+  void* _cnst;
+  void* _elem;
+  void* _var;
   lmm_constraint_t cnst = nullptr;
-  lmm_element_t elem = nullptr;
-  lmm_variable_t var = nullptr;
-  xbt_swag_t cnst_list = nullptr;
-  xbt_swag_t var_list = nullptr;
-  xbt_swag_t elem_list = nullptr;
-  xbt_strbuff_t buf = xbt_strbuff_new();
-  double sum = 0.0;
+  lmm_element_t elem    = nullptr;
+  lmm_variable_t var    = nullptr;
+  xbt_swag_t cnst_list  = nullptr;
+  xbt_swag_t var_list   = nullptr;
+  xbt_swag_t elem_list  = nullptr;
+  std::string buf       = std::string("MAX-MIN ( ");
 
   /* Printing Objective */
   var_list = &(sys->variable_set);
-  xbt_strbuff_append(buf, "MAX-MIN ( ");
   xbt_swag_foreach(_var, var_list) {
     var = (lmm_variable_t)_var;
-    xbt_strbuff_printf(buf, "'%d'(%f) ", var->id_int, var->weight);
+    buf = buf + "'" + std::to_string(var->id_int) + "'(" + std::to_string(var->weight) + ") ";
   }
-  xbt_strbuff_append(buf, ")");
-  XBT_DEBUG("%20s", buf->data);
-  xbt_strbuff_clear(buf);
+  buf += ")";
+  XBT_DEBUG("%20s", buf.c_str());
+  buf.clear();
 
   XBT_DEBUG("Constraints");
   /* Printing Constraints */
   cnst_list = &(sys->active_constraint_set);
   xbt_swag_foreach(_cnst, cnst_list) {
-  cnst = (lmm_constraint_t)_cnst;
-    sum = 0.0;
+    cnst       = (lmm_constraint_t)_cnst;
+    double sum = 0.0;
     //Show  the enabled variables
     elem_list = &(cnst->enabled_element_set);
-    xbt_strbuff_append(buf, "\t");
-    xbt_strbuff_printf(buf, "%s(", (cnst->sharing_policy)?"":"max");
+    buf += "\t";
+    buf += ((cnst->sharing_policy) ? "(" : "max(");
     xbt_swag_foreach(_elem, elem_list) {
       elem = (lmm_element_t)_elem;
-      xbt_strbuff_printf(buf, "%f.'%d'(%f) %s ", elem->value,
-              elem->variable->id_int, elem->variable->value,(cnst->sharing_policy)?"+":",");
+      buf  = buf + std::to_string(elem->value) + ".'" + std::to_string(elem->variable->id_int) + "'(" +
+            std::to_string(elem->variable->value) + ")" + ((cnst->sharing_policy) ? " + " : " , ");
       if(cnst->sharing_policy)
         sum += elem->value * elem->variable->value;
-      else 
+      else
         sum = MAX(sum,elem->value * elem->variable->value);
     }
     //TODO: Adding disabled elements only for test compatibility, but do we really want them to be printed?
     elem_list = &(cnst->disabled_element_set);
     xbt_swag_foreach(_elem, elem_list) {
       elem = (lmm_element_t)_elem;
-      xbt_strbuff_printf(buf, "%f.'%d'(%f) %s ", elem->value,
-              elem->variable->id_int, elem->variable->value,(cnst->sharing_policy)?"+":",");
+      buf  = buf + std::to_string(elem->value) + ".'" + std::to_string(elem->variable->id_int) + "'(" +
+            std::to_string(elem->variable->value) + ")" + ((cnst->sharing_policy) ? " + " : " , ");
       if(cnst->sharing_policy)
         sum += elem->value * elem->variable->value;
-      else 
+      else
         sum = MAX(sum,elem->value * elem->variable->value);
     }
 
-    xbt_strbuff_printf(buf, "0) <= %f ('%d')", cnst->bound, cnst->id_int);
+    buf = buf + "0) <= " + std::to_string(cnst->bound) + " ('" + std::to_string(cnst->id_int) + "')";
 
-    if (!cnst->sharing_policy) {
-      xbt_strbuff_printf(buf, " [MAX-Constraint]");
+    if (not cnst->sharing_policy) {
+      buf += " [MAX-Constraint]";
     }
-    XBT_DEBUG("%s", buf->data);
-    xbt_strbuff_clear(buf);
-    xbt_assert(!double_positive(sum - cnst->bound, cnst->bound*sg_maxmin_precision),
-        "Incorrect value (%f is not smaller than %f): %g", sum, cnst->bound, sum - cnst->bound);
-       //if(double_positive(sum - cnst->bound, cnst->bound*sg_maxmin_precision))
-       //XBT_ERROR("Incorrect value (%f is not smaller than %f): %g",sum, cnst->bound, sum - cnst->bound);
+    XBT_DEBUG("%s", buf.c_str());
+    buf.clear();
+    xbt_assert(not double_positive(sum - cnst->bound, cnst->bound * sg_maxmin_precision),
+               "Incorrect value (%f is not smaller than %f): %g", sum, cnst->bound, sum - cnst->bound);
+    // if(double_positive(sum - cnst->bound, cnst->bound*sg_maxmin_precision))
+    // XBT_ERROR("Incorrect value (%f is not smaller than %f): %g",sum, cnst->bound, sum - cnst->bound);
   }
 
   XBT_DEBUG("Variables");
@@ -695,14 +701,12 @@ void lmm_print(lmm_system_t sys)
   var = (lmm_variable_t)_var;
     if (var->bound > 0) {
       XBT_DEBUG("'%d'(%f) : %f (<=%f)", var->id_int, var->weight, var->value, var->bound);
-      xbt_assert(!double_positive(var->value - var->bound, var->bound*sg_maxmin_precision),
-                  "Incorrect value (%f is not smaller than %f", var->value, var->bound);
+      xbt_assert(not double_positive(var->value - var->bound, var->bound * sg_maxmin_precision),
+                 "Incorrect value (%f is not smaller than %f", var->value, var->bound);
     } else {
       XBT_DEBUG("'%d'(%f) : %f", var->id_int, var->weight, var->value);
     }
   }
-
-  xbt_strbuff_free(buf);
 }
 
 void lmm_solve(lmm_system_t sys)
@@ -717,7 +721,7 @@ void lmm_solve(lmm_system_t sys)
   double min_usage = -1;
   double min_bound = -1;
 
-  if (!(sys->modified))
+  if (not sys->modified)
     return;
 
   XBT_IN("(sys=%p)", sys);
@@ -752,7 +756,7 @@ void lmm_solve(lmm_system_t sys)
     /* INIT: Collect constraints that actually need to be saturated (i.e remaining  and usage are strictly positive)
      * into cnst_light_tab. */
     cnst->remaining = cnst->bound;
-    if (!double_positive(cnst->remaining, cnst->bound*sg_maxmin_precision))
+    if (not double_positive(cnst->remaining, cnst->bound * sg_maxmin_precision))
       continue;
     cnst->usage = 0;
     elem_list = &(cnst->enabled_element_set);
@@ -767,7 +771,7 @@ void lmm_solve(lmm_system_t sys)
 
         make_elem_active(elem);
         simgrid::surf::Action *action = static_cast<simgrid::surf::Action*>(elem->variable->id);
-        if (sys->keep_track && !action->is_linked())
+        if (sys->keep_track && not action->is_linked())
           sys->keep_track->push_back(*action);
       }
     }
@@ -843,8 +847,8 @@ void lmm_solve(lmm_system_t sys)
           double_update(&(cnst->remaining),  elem->value * var->value, cnst->bound*sg_maxmin_precision);
           double_update(&(cnst->usage), elem->value / var->weight, sg_maxmin_precision);
           //If the constraint is saturated, remove it from the set of active constraints (light_tab)
-          if(!double_positive(cnst->usage,sg_maxmin_precision) ||
-             !double_positive(cnst->remaining,cnst->bound*sg_maxmin_precision)) {
+          if (not double_positive(cnst->usage, sg_maxmin_precision) ||
+              not double_positive(cnst->remaining, cnst->bound * sg_maxmin_precision)) {
             if (cnst->cnst_light) {
               int index = (cnst->cnst_light-cnst_light_tab);
               XBT_DEBUG("index: %d \t cnst_light_num: %d \t || usage: %f remaining: %f bound: %f  ",
@@ -874,8 +878,8 @@ void lmm_solve(lmm_system_t sys)
               cnst->usage = MAX(cnst->usage, elem->value / elem->variable->weight);
           }
           //If the constraint is saturated, remove it from the set of active constraints (light_tab)
-          if(!double_positive(cnst->usage,sg_maxmin_precision) ||
-             !double_positive(cnst->remaining,cnst->bound*sg_maxmin_precision)) {
+          if (not double_positive(cnst->usage, sg_maxmin_precision) ||
+              not double_positive(cnst->remaining, cnst->bound * sg_maxmin_precision)) {
             if(cnst->cnst_light) {
               int index = (cnst->cnst_light-cnst_light_tab);
               XBT_DEBUG("index: %d \t cnst_light_num: %d \t || \t cnst: %p \t cnst->cnst_light: %p "
@@ -932,11 +936,11 @@ void lmm_solve(lmm_system_t sys)
 }
 
 /** \brief Attribute the value bound to var->bound.
- * 
+ *
  *  \param sys the lmm_system_t
  *  \param var the lmm_variable_t
  *  \param bound the new bound to associate with var
- * 
+ *
  *  Makes var->bound equal to bound. Whenever this function is called a change is  signed in the system. To
  *  avoid false system changing detection it is a good idea to test (bound != 0) before calling it.
  */
@@ -954,20 +958,18 @@ int lmm_concurrency_slack(lmm_constraint_t cnstr){
   if(cnstr->concurrency_limit<0)
     return 666;
 
-  return  cnstr->concurrency_limit - cnstr->concurrency_current;  
+  return  cnstr->concurrency_limit - cnstr->concurrency_current;
 }
 
 /** \brief Measure the minimum concurrency slack across all constraints where the given var is involved */
 int lmm_cnstrs_min_concurrency_slack(lmm_variable_t var){
-  int i;
-  //FIXME MARTIN: Replace by infinite value std::numeric_limits<int>::(max)(), or something better within Simgrid?
-  int slack,minslack=666;
-  for (i = 0; i < var->cnsts_number; i++) {
-    slack=lmm_concurrency_slack(var->cnsts[i].constraint);
+  int minslack = std::numeric_limits<int>::max();
+  for (int i = 0; i < var->cnsts_number; i++) {
+    int slack = lmm_concurrency_slack(var->cnsts[i].constraint);
 
     //This is only an optimization, to avoid looking at more constraints when slack is already zero
     //Disable it when debugging to let lmm_concurrency_slack catch nasty things
-    if(!slack   && !XBT_LOG_ISENABLED(surf_maxmin, xbt_log_priority_debug))
+    if (not slack && not XBT_LOG_ISENABLED(surf_maxmin, xbt_log_priority_debug))
       return 0;
 
     if(minslack>slack)
@@ -979,7 +981,7 @@ int lmm_cnstrs_min_concurrency_slack(lmm_variable_t var){
 
 /* /Check if a variable can be enabled
  *
- * Make sure to set staged_weight before, if your intent is only to check concurrency 
+ * Make sure to set staged_weight before, if your intent is only to check concurrency
  */
 int lmm_can_enable_var(lmm_variable_t var){
   return var->staged_weight>0 && lmm_cnstrs_min_concurrency_slack(var)>=var->concurrency_share;
@@ -1014,7 +1016,7 @@ void lmm_enable_var(lmm_system_t sys, lmm_variable_t var){
 
   //When used within lmm_on_disabled_var, we would get an assertion fail, because transiently there can be variables
   // that are staged and could be activated.
-  //Anyway, caller functions all call lmm_check_concurrency() in the end. 
+  //Anyway, caller functions all call lmm_check_concurrency() in the end.
   //  lmm_check_concurrency(sys);
 }
 
@@ -1022,7 +1024,7 @@ void lmm_disable_var(lmm_system_t sys, lmm_variable_t var){
   int i;
   lmm_element_t elem;
 
-  xbt_assert(!var->staged_weight,"Staged weight should have been cleared");
+  xbt_assert(not var->staged_weight, "Staged weight should have been cleared");
   //Disabling the variable, move to var to list tail. Subtility is: here, we need to call lmm_update_modified_set BEFORE
   //moving the last element of var.
   xbt_swag_remove(var, &(sys->variable_set));
@@ -1044,32 +1046,29 @@ void lmm_disable_var(lmm_system_t sys, lmm_variable_t var){
   var->value = 0.0;
   lmm_check_concurrency(sys);
 }
- 
+
 /* /brief Find variables that can be enabled and enable them.
- * 
+ *
  * Assuming that the variable has already been removed from non-zero weights
  * Can we find a staged variable to add?
  * If yes, check that none of the constraints that this variable is involved in is at the limit of its concurrency
  * And then add it to enabled variables
  */
 void lmm_on_disabled_var(lmm_system_t sys, lmm_constraint_t cnstr){
-  lmm_element_t elem;
-  lmm_element_t nextelem;
-  int numelem;
 
   if(cnstr->concurrency_limit<0)
     return;
 
-  numelem=xbt_swag_size(&(cnstr->disabled_element_set));
-  if(!numelem)
+  int numelem = xbt_swag_size(&(cnstr->disabled_element_set));
+  if (not numelem)
     return;
 
-  elem= (lmm_element_t) xbt_swag_getFirst(&(cnstr->disabled_element_set));
+  lmm_element_t elem = (lmm_element_t)xbt_swag_getFirst(&(cnstr->disabled_element_set));
 
   //Cannot use xbt_swag_foreach, because lmm_enable_var will modify disabled_element_set.. within the loop
-  while(numelem-- && elem ){
+  while (numelem-- && elem) {
 
-    nextelem = (lmm_element_t) xbt_swag_getNext(elem, cnstr->disabled_element_set.offset);      
+    lmm_element_t nextelem = (lmm_element_t)xbt_swag_getNext(elem, cnstr->disabled_element_set.offset);
 
     if (elem->variable->staged_weight>0 ){
       //Found a staged variable
@@ -1089,7 +1088,7 @@ void lmm_on_disabled_var(lmm_system_t sys, lmm_constraint_t cnstr){
 
   //We could get an assertion fail, because transiently there can be variables that are staged and could be activated.
   //And we need to go through all constraints of the disabled var before getting back a coherent state.
-  //Anyway, caller functions all call lmm_check_concurrency() in the end. 
+  //Anyway, caller functions all call lmm_check_concurrency() in the end.
   //  lmm_check_concurrency(sys);
 }
 
@@ -1098,7 +1097,6 @@ void lmm_on_disabled_var(lmm_system_t sys, lmm_constraint_t cnstr){
  */
 void lmm_update_variable_weight(lmm_system_t sys, lmm_variable_t var, double weight)
 {
-  int minslack;
 
   xbt_assert(weight>=0,"Variable weight should not be negative!");
 
@@ -1115,8 +1113,8 @@ void lmm_update_variable_weight(lmm_system_t sys, lmm_variable_t var, double wei
   //Are we enabling this variable?
   if (enabling_var){
     var->staged_weight = weight;
-    minslack=lmm_cnstrs_min_concurrency_slack(var);
-    if(minslack<var->concurrency_share){      
+    int minslack       = lmm_cnstrs_min_concurrency_slack(var);
+    if (minslack < var->concurrency_share) {
       XBT_DEBUG("Staging var (instead of enabling) because min concurrency slack %i, with weight %f and concurrency"
                 " share %i", minslack, weight, var->concurrency_share);
       return;
@@ -1133,7 +1131,6 @@ void lmm_update_variable_weight(lmm_system_t sys, lmm_variable_t var, double wei
   lmm_check_concurrency(sys);
 
   XBT_OUT();
-  return;
 }
 
 double lmm_get_variable_weight(lmm_variable_t var)
@@ -1182,12 +1179,12 @@ static void lmm_update_modified_set_rec(lmm_system_t sys, lmm_constraint_t cnst)
     s_lmm_element_t *cnsts = var->cnsts;
     int i;
     for (i = 0; var->visited != sys->visited_counter && i < var->cnsts_number ; i++) {
-      if (cnsts[i].constraint != cnst && !xbt_swag_belongs(cnsts[i].constraint, &sys->modified_constraint_set)) {
+      if (cnsts[i].constraint != cnst && not xbt_swag_belongs(cnsts[i].constraint, &sys->modified_constraint_set)) {
         xbt_swag_insert(cnsts[i].constraint, &sys->modified_constraint_set);
         lmm_update_modified_set_rec(sys, cnsts[i].constraint);
       }
     }
-    //var will be ignored in later visits as long as sys->visited_counter does not move 
+    //var will be ignored in later visits as long as sys->visited_counter does not move
     var->visited = sys->visited_counter;
   }
 }
@@ -1195,7 +1192,7 @@ static void lmm_update_modified_set_rec(lmm_system_t sys, lmm_constraint_t cnst)
 static void lmm_update_modified_set(lmm_system_t sys, lmm_constraint_t cnst)
 {
   /* nothing to do if selective update isn't active */
-  if (sys->selective_update_active && !xbt_swag_belongs(cnst, &sys->modified_constraint_set)) {
+  if (sys->selective_update_active && not xbt_swag_belongs(cnst, &sys->modified_constraint_set)) {
     xbt_swag_insert(cnst, &sys->modified_constraint_set);
     lmm_update_modified_set_rec(sys, cnst);
   }
@@ -1217,7 +1214,7 @@ static void lmm_remove_all_modified_set(lmm_system_t sys)
   void *_var;
     xbt_swag_foreach(_var, &sys->variable_set)
       ((lmm_variable_t)_var)->visited = 0;
-  } 
+  }
   xbt_swag_reset(&sys->modified_constraint_set);
 }
 
@@ -1248,30 +1245,38 @@ double lmm_constraint_get_usage(lmm_constraint_t cnst) {
    }
   return usage;
 }
+int lmm_constraint_get_variable_amount(lmm_constraint_t cnst) {
+  int usage = 0;
+  xbt_swag_t elem_list = &(cnst->enabled_element_set);
+  void *_elem;
 
-void lmm_check_concurrency(lmm_system_t sys){
-  void* _cnst;
-  void* _elem;
-  void* _var;
-  lmm_element_t elem;
-  lmm_constraint_t cnst;
-  lmm_variable_t var;
-  int concurrency;
-  int i,belong_to_enabled,belong_to_disabled,belong_to_active;
+  xbt_swag_foreach(_elem, elem_list) {
+    lmm_element_t elem = (lmm_element_t)_elem;
+    if (elem->value > 0)
+      usage++;
+  }
+ return usage;
+}
 
+void lmm_check_concurrency(lmm_system_t sys){
   //These checks are very expensive, so do them only if we want to debug SURF LMM
   if (XBT_LOG_ISENABLED(surf_maxmin, xbt_log_priority_debug)) {
-    xbt_swag_foreach(_cnst, &(sys->constraint_set)) {
-      cnst = (lmm_constraint_t) _cnst;
-      concurrency=0;
-      xbt_swag_foreach(_elem, &(cnst->enabled_element_set)) {
-        elem = (lmm_element_t)_elem;
+    void* cnstIt;
+    xbt_swag_foreach(cnstIt, &(sys->constraint_set))
+    {
+      lmm_constraint_t cnst = (lmm_constraint_t)cnstIt;
+      int concurrency       = 0;
+      void* elemIt;
+      xbt_swag_foreach(elemIt, &(cnst->enabled_element_set))
+      {
+        lmm_element_t elem = (lmm_element_t)elemIt;
         xbt_assert(elem->variable->weight > 0);
         concurrency+=lmm_element_concurrency(elem);
       }
 
-      xbt_swag_foreach(_elem, &(cnst->disabled_element_set)) {
-        elem = (lmm_element_t)_elem;
+      xbt_swag_foreach(elemIt, &(cnst->disabled_element_set))
+      {
+        lmm_element_t elem = (lmm_element_t)elemIt;
         //We should have staged variables only if concurrency is reached in some constraint
         xbt_assert(cnst->concurrency_limit<0 || elem->variable->staged_weight==0 ||
                    lmm_cnstrs_min_concurrency_slack(elem->variable) < elem->variable->concurrency_share,
@@ -1283,18 +1288,20 @@ void lmm_check_concurrency(lmm_system_t sys){
     }
 
     //Check that for each variable, all corresponding elements are in the same state (i.e. same element sets)
-    xbt_swag_foreach(_var, &(sys->variable_set)) {
-      var= (lmm_variable_t) _var;
+    void* varIt;
+    xbt_swag_foreach(varIt, &(sys->variable_set))
+    {
+      lmm_variable_t var = (lmm_variable_t)varIt;
 
-      if(!var->cnsts_number)
+      if (not var->cnsts_number)
         continue;
 
-      elem = &var->cnsts[0];
-      belong_to_enabled=xbt_swag_belongs(elem,&(elem->constraint->enabled_element_set));
-      belong_to_disabled=xbt_swag_belongs(elem,&(elem->constraint->disabled_element_set));
-      belong_to_active=xbt_swag_belongs(elem,&(elem->constraint->active_element_set));
+      lmm_element_t elem     = &var->cnsts[0];
+      int belong_to_enabled  = xbt_swag_belongs(elem, &(elem->constraint->enabled_element_set));
+      int belong_to_disabled = xbt_swag_belongs(elem, &(elem->constraint->disabled_element_set));
+      int belong_to_active   = xbt_swag_belongs(elem, &(elem->constraint->active_element_set));
 
-      for (i = 1; i < var->cnsts_number; i++) {
+      for (int i = 1; i < var->cnsts_number; i++) {
         elem = &var->cnsts[i];
         xbt_assert(belong_to_enabled==xbt_swag_belongs(elem,&(elem->constraint->enabled_element_set)),
                    "Variable inconsistency (1): enabled_element_set");