From: alegrand <alegrand@48e7efb5-ca39-0410-a469-dd3cf9ba447f>
Date: Tue, 7 Dec 2004 18:05:27 +0000 (+0000)
Subject: If a system has not been modified between two successive calls to lmm_solve,
X-Git-Tag: v3.3~4804
X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/commitdiff_plain/bb671f9a46d6bba398acb63681457a3ad5b8c1dc

If a system has not been modified between two successive calls to lmm_solve,
then no extra computation is done.


git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/simgrid/simgrid/trunk@546 48e7efb5-ca39-0410-a469-dd3cf9ba447f
---

diff --git a/src/include/surf/maxmin.h b/src/include/surf/maxmin.h
index 4d4f845953..4602baf46f 100644
--- a/src/include/surf/maxmin.h
+++ b/src/include/surf/maxmin.h
@@ -6,9 +6,7 @@
 #ifndef _SURF_MAXMIN_H
 #define _SURF_MAXMIN_H
 
-typedef long double xbt_maxmin_float_t;
-#define XBT_MAXMIN_FLOAT_T "%Lg"	/* for printing purposes */
-
+#include "xbt/misc.h"
 typedef struct lmm_variable *lmm_variable_t;
 typedef struct lmm_constraint *lmm_constraint_t;
 typedef struct lmm_system *lmm_system_t;
@@ -40,11 +38,11 @@ void *lmm_variable_id(lmm_variable_t var);
 
 void lmm_update(lmm_system_t sys, lmm_constraint_t cnst,
 		lmm_variable_t var, xbt_maxmin_float_t value);
-void lmm_update_variable_bound(lmm_variable_t var,
+void lmm_update_variable_bound(lmm_system_t sys, lmm_variable_t var,
 			       xbt_maxmin_float_t bound);
-void lmm_update_variable_weight(lmm_variable_t var,
+void lmm_update_variable_weight(lmm_system_t sys, lmm_variable_t var,
 				xbt_maxmin_float_t weight);
-void lmm_update_constraint_bound(lmm_constraint_t cnst,
+void lmm_update_constraint_bound(lmm_system_t sys, lmm_constraint_t cnst,
 				 xbt_maxmin_float_t bound);
 
 int lmm_constraint_used(lmm_system_t sys, lmm_constraint_t cnst);
diff --git a/src/surf/maxmin.c b/src/surf/maxmin.c
index 637555f5bf..3e94153e35 100644
--- a/src/surf/maxmin.c
+++ b/src/surf/maxmin.c
@@ -27,6 +27,7 @@ lmm_system_t lmm_system_new(void)
 
   l = xbt_new0(s_lmm_system_t, 1);
 
+  l->modified = 0;
   xbt_swag_init(&(l->variable_set),
 		xbt_swag_offset(var, variable_set_hookup));
   xbt_swag_init(&(l->constraint_set),
@@ -62,6 +63,8 @@ void lmm_variable_disable(lmm_system_t sys, lmm_variable_t var)
   int i;
   lmm_element_t elem = NULL;
 
+  sys->modified = 1;
+
   for (i = 0; i < var->cnsts_number; i++) {
     elem = &var->cnsts[i];
     xbt_swag_remove(elem, &(elem->constraint->element_set));
@@ -150,6 +153,8 @@ void lmm_expand(lmm_system_t sys, lmm_constraint_t cnst,
 {
   lmm_element_t elem = NULL;
 
+  sys->modified = 1;
+
   if (var->cnsts_number >= var->cnsts_size)
     abort();
 
@@ -191,6 +196,8 @@ static void saturated_constraints_update(lmm_system_t sys,
 {
   lmm_constraint_t useless_cnst = NULL;
 
+  sys->modified = 1;
+
   if (cnst->remaining <= 0)
     return;
   if ((*min_usage < 0) || (*min_usage > cnst->remaining / cnst->usage)) {
@@ -212,6 +219,8 @@ static void saturated_variables_update(lmm_system_t sys)
   lmm_element_t elem = NULL;
   xbt_swag_t elem_list = NULL;
 
+  sys->modified = 1;
+
   cnst_list = &(sys->saturated_constraint_set);
   while ((cnst = xbt_swag_getFirst(cnst_list))) {
 /*   xbt_swag_foreach(cnst, cnst_list) { */
@@ -233,6 +242,8 @@ void lmm_solve(lmm_system_t sys)
   xbt_swag_t elem_list = NULL;
   xbt_maxmin_float_t min_usage = -1;
 
+  if(!(sys->modified)) return;
+
   /* Init */
   var_list = &(sys->variable_set);
   xbt_swag_foreach(var, var_list) {
@@ -301,6 +312,8 @@ void lmm_solve(lmm_system_t sys)
     saturated_variables_update(sys);
 
   } while (xbt_swag_size(&(sys->saturated_variable_set)));
+
+  sys->modified = 0;
 }
 
 /* Not a O(1) function */
@@ -311,6 +324,7 @@ void lmm_update(lmm_system_t sys, lmm_constraint_t cnst,
   int i;
   lmm_element_t elem = NULL;
 
+  sys->modified = 1;
   for (i = 0; i < var->cnsts_number; i++)
     if (var->cnsts[i].constraint == cnst) {
       elem->value = value;
@@ -318,21 +332,24 @@ void lmm_update(lmm_system_t sys, lmm_constraint_t cnst,
     }
 }
 
-void lmm_update_variable_bound(lmm_variable_t var,
+void lmm_update_variable_bound(lmm_system_t sys, lmm_variable_t var,
 			       xbt_maxmin_float_t bound)
 {
+  sys->modified = 1;
   var->bound = bound;
 }
 
-void lmm_update_variable_weight(lmm_variable_t var,
+void lmm_update_variable_weight(lmm_system_t sys, lmm_variable_t var,
 				xbt_maxmin_float_t weight)
 {
+  sys->modified = 1;
   var->weight = weight;
 }
 
-void lmm_update_constraint_bound(lmm_constraint_t cnst,
+void lmm_update_constraint_bound(lmm_system_t sys, lmm_constraint_t cnst,
 				 xbt_maxmin_float_t bound)
 {
+  sys->modified = 1;
   cnst->bound = bound;
 }
 
diff --git a/src/surf/maxmin_private.h b/src/surf/maxmin_private.h
index 99f1be6b39..a2979244f0 100644
--- a/src/surf/maxmin_private.h
+++ b/src/surf/maxmin_private.h
@@ -51,6 +51,7 @@ typedef struct lmm_variable {
 } s_lmm_variable_t;
 
 typedef struct lmm_system {
+  int modified;
   s_xbt_swag_t variable_set;	/* a list of lmm_variable_t */
   s_xbt_swag_t constraint_set;	/* a list of lmm_constraint_t */