-/* Authors: Arnaud Legrand */
+/* $Id$ */
+
+/* Copyright (c) 2004 Arnaud Legrand. 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. */
+ * under the terms of the license (GNU LGPL) which comes with this package. */
+
+#include "xbt/sysdep.h"
+#include "xbt/error.h"
#include "maxmin_private.h"
+#include <stdlib.h>
+XBT_LOG_NEW_DEFAULT_SUBCATEGORY(maxmin, surf,
+ "Logging specific to the SURF maxmin module");
+
+lmm_system_t lmm_system_new(void)
+{
+ lmm_system_t l = NULL;
+ s_lmm_variable_t var;
+ s_lmm_constraint_t cnst;
+
+ 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),
+ xbt_swag_offset(cnst, constraint_set_hookup));
+
+ xbt_swag_init(&(l->active_constraint_set),
+ xbt_swag_offset(cnst, active_constraint_set_hookup));
+
+ xbt_swag_init(&(l->saturated_variable_set),
+ xbt_swag_offset(var, saturated_variable_set_hookup));
+ xbt_swag_init(&(l->saturated_constraint_set),
+ xbt_swag_offset(cnst, saturated_constraint_set_hookup));
+
+ return l;
+}
+
+void lmm_system_free(lmm_system_t sys)
+{
+ lmm_variable_t var = NULL;
+ lmm_constraint_t cnst = NULL;
+
+ while ((var = extract_variable(sys)))
+ lmm_var_free(sys, var);
+
+ while ((cnst = extract_constraint(sys)))
+ lmm_cnst_free(sys, cnst);
+
+ free(sys);
+}
+
+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));
+ xbt_swag_remove(elem, &(elem->constraint->active_element_set));
+ if (!xbt_swag_size(&(elem->constraint->element_set)))
+ make_constraint_inactive(sys, elem->constraint);
+ }
+ var->cnsts_number = 0;
+}
+
+static void lmm_var_free(lmm_system_t sys, lmm_variable_t var)
+{
+
+ lmm_variable_disable(sys, var);
+ memset(var->cnsts,0,var->cnsts_size*sizeof(s_lmm_element_t));
+ free(var->cnsts);
+ free(var);
+}
+
+static void lmm_cnst_free(lmm_system_t sys, lmm_constraint_t cnst)
+{
+/* xbt_assert0(xbt_swag_size(&(cnst->element_set)), */
+/* "This list should be empty!"); */
+ remove_active_constraint(sys, cnst);
+ free(cnst);
+}
+
+lmm_constraint_t lmm_constraint_new(lmm_system_t sys, void *id,
+ double bound_value)
+{
+ lmm_constraint_t cnst = NULL;
+ s_lmm_element_t elem;
+
+ cnst = xbt_new0(s_lmm_constraint_t, 1);
+ cnst->id = id;
+ xbt_swag_init(&(cnst->element_set),
+ xbt_swag_offset(elem, element_set_hookup));
+ xbt_swag_init(&(cnst->active_element_set),
+ xbt_swag_offset(elem, active_element_set_hookup));
+
+ cnst->bound = bound_value;
+ cnst->usage = 0;
+ insert_constraint(sys, cnst);
+
+ return cnst;
+}
+
+void lmm_constraint_free(lmm_system_t sys, lmm_constraint_t cnst)
+{
+ remove_constraint(sys, cnst);
+ lmm_cnst_free(sys, cnst);
+}
+
+lmm_variable_t lmm_variable_new(lmm_system_t sys, void *id,
+ double weight,
+ double bound, int number_of_constraints)
+{
+ lmm_variable_t var = NULL;
+ int i;
+ var = xbt_new0(s_lmm_variable_t, 1);
+ var->id = id;
+ var->cnsts = xbt_new0(s_lmm_element_t, number_of_constraints);
+ for(i=0; i<number_of_constraints; i++) {
+ /* Should be useless because of the
+ calloc but it seems to help valgrind... */
+ var->cnsts[i].element_set_hookup.next = NULL;
+ var->cnsts[i].element_set_hookup.prev = NULL;
+ var->cnsts[i].active_element_set_hookup.next = NULL;
+ var->cnsts[i].active_element_set_hookup.prev = NULL;
+ var->cnsts[i].constraint = NULL;
+ var->cnsts[i].variable = NULL;
+ var->cnsts[i].value = 0.0;
+ }
+ var->cnsts_size = number_of_constraints;
+ var->cnsts_number = 0; /* Should be useless because of the
+ calloc but it seems to help valgrind... */
+ var->weight = weight;
+ var->bound = bound;
+ var->value = 0.0;
+ if(weight) xbt_swag_insert_at_head(var,&(sys->variable_set));
+ else xbt_swag_insert_at_tail(var,&(sys->variable_set));
+
+ return var;
+}
+
+void lmm_variable_free(lmm_system_t sys, lmm_variable_t var)
+{
+ remove_variable(sys, var);
+ lmm_var_free(sys, var);
+}
+
+double lmm_variable_getvalue(lmm_variable_t var)
+{
+ return (var->value);
+}
+
+void lmm_expand(lmm_system_t sys, lmm_constraint_t cnst,
+ lmm_variable_t var, double value)
+{
+ lmm_element_t elem = NULL;
+
+ sys->modified = 1;
+
+ xbt_assert0(var->cnsts_number < var->cnsts_size,
+ "Too much constraints");
+
+ elem = &(var->cnsts[var->cnsts_number++]);
+
+ elem->value = value;
+ elem->constraint = cnst;
+ elem->variable = var;
+
+ if(var->weight) xbt_swag_insert_at_head(elem,&(elem->constraint->element_set));
+ else xbt_swag_insert_at_tail(elem,&(elem->constraint->element_set));
+
+ make_constraint_active(sys, cnst);
+}
+
+void lmm_expand_add(lmm_system_t sys, lmm_constraint_t cnst,
+ lmm_variable_t var, double value)
+{
+ int i ;
+ sys->modified = 1;
+
+ for(i=0; i< var->cnsts_number ; i++)
+ if(var->cnsts[i].constraint == cnst) break;
+
+ if(i<var->cnsts_number) var->cnsts[i].value +=value;
+ else lmm_expand(sys,cnst,var,value);
+}
+
+lmm_constraint_t lmm_get_cnst_from_var(lmm_system_t sys,
+ lmm_variable_t var, int num)
+{
+ if (num < var->cnsts_number)
+ return (var->cnsts[num].constraint);
+ else
+ return NULL;
+}
+
+int lmm_get_number_of_cnst_from_var(lmm_system_t sys, lmm_variable_t var)
+{
+ return (var->cnsts_number);
+}
+
+lmm_variable_t lmm_get_var_from_cnst(lmm_system_t sys,
+ lmm_constraint_t cnst,
+ lmm_variable_t * var)
+{
+ if (!(*var))
+ xbt_swag_getFirst(&(cnst->element_set));
+ else
+ *var = xbt_swag_getNext(*var, cnst->element_set.offset);
+ return *var;
+}
+
+void *lmm_constraint_id(lmm_constraint_t cnst)
+{
+ return cnst->id;
+}
+
+void *lmm_variable_id(lmm_variable_t var)
+{
+ return var->id;
+}
+
+static void saturated_constraint_set_update(lmm_system_t sys,
+ lmm_constraint_t cnst,
+ double *min_usage)
+{
+ lmm_constraint_t useless_cnst = NULL;
+
+ if (cnst->usage <= 0)
+ return;
+ if (cnst->remaining <= 0)
+ return;
+ if ((*min_usage < 0) || (*min_usage > cnst->remaining / cnst->usage)) {
+ *min_usage = cnst->remaining / cnst->usage;
+
+ while ((useless_cnst =
+ xbt_swag_getFirst(&(sys->saturated_constraint_set))))
+ xbt_swag_remove(useless_cnst, &(sys->saturated_constraint_set));
+
+ xbt_swag_insert(cnst, &(sys->saturated_constraint_set));
+ } else if (*min_usage == cnst->remaining / cnst->usage) {
+ xbt_swag_insert(cnst, &(sys->saturated_constraint_set));
+ }
+}
+
+static void saturated_variable_set_update(lmm_system_t sys)
+{
+ lmm_constraint_t cnst = NULL;
+ xbt_swag_t cnst_list = NULL;
+ lmm_element_t elem = NULL;
+ xbt_swag_t elem_list = NULL;
+
+ cnst_list = &(sys->saturated_constraint_set);
+ while ((cnst = xbt_swag_getFirst(cnst_list))) {
+ elem_list = &(cnst->active_element_set);
+ xbt_swag_foreach(elem, elem_list) {
+ if(elem->variable->weight<=0) break;
+ if ((elem->value > 0))
+ xbt_swag_insert(elem->variable, &(sys->saturated_variable_set));
+ }
+ xbt_swag_remove(cnst, cnst_list);
+ }
+
+}
+
+void lmm_solve(lmm_system_t sys)
+{
+ lmm_variable_t var = NULL;
+ lmm_constraint_t cnst = NULL;
+ lmm_element_t elem = NULL;
+ xbt_swag_t cnst_list = NULL;
+ xbt_swag_t var_list = NULL;
+ xbt_swag_t elem_list = NULL;
+ double min_usage = -1;
+
+ if (!(sys->modified))
+ return;
+
+ /* Init */
+ var_list = &(sys->variable_set);
+ DEBUG1("Variable set : %d", xbt_swag_size(var_list));
+ xbt_swag_foreach(var, var_list) {
+ var->value = 0.0;
+ }
+
+
+ /* Compute Usage and store the variables that reach the maximum */
+
+ cnst_list = &(sys->active_constraint_set);
+ DEBUG1("cnst_list : %d", xbt_swag_size(cnst_list));
+ xbt_swag_foreach(cnst, cnst_list) {
+ /* INIT */
+ cnst->remaining = cnst->bound;
+ cnst->usage = 0;
+ elem_list = &(cnst->element_set);
+ xbt_swag_foreach(elem, elem_list) {
+ if(elem->variable->weight <=0) break;
+ if ((elem->value > 0)) {
+ cnst->usage += elem->value / elem->variable->weight;
+ make_elem_active(elem);
+ }
+ }
+
+ /* Saturated constraints update */
+ saturated_constraint_set_update(sys, cnst, &min_usage);
+ }
+
+ saturated_variable_set_update(sys);
+
+ /* Saturated variables update */
+
+ do {
+ /* Fix the variables that have to be */
+ var_list = &(sys->saturated_variable_set);
+
+ xbt_swag_foreach(var, var_list) {
+ /* First check if some of these variables have reach their upper
+ bound and update min_usage accordingly. */
+ if ((var->bound > 0) && (var->bound / var->weight < min_usage)) {
+ min_usage = var->bound / var->weight;
+ }
+ }
+
+
+ while ((var = xbt_swag_getFirst(var_list))) {
+ int i;
+
+ var->value = min_usage / var->weight;
+
+ /* Update usage */
+
+ for (i = 0; i < var->cnsts_number; i++) {
+ elem = &var->cnsts[i];
+ cnst = elem->constraint;
+ cnst->remaining -= elem->value * var->value;
+ cnst->usage -= elem->value / var->weight;
+ make_elem_inactive(elem);
+ }
+ xbt_swag_remove(var, var_list);
+ }
+
+ /* Find out which variables reach the maximum */
+ cnst_list = &(sys->active_constraint_set);
+ min_usage = -1;
+ xbt_swag_foreach(cnst, cnst_list) {
+ saturated_constraint_set_update(sys, cnst, &min_usage);
+ }
+ saturated_variable_set_update(sys);
+
+ } while (xbt_swag_size(&(sys->saturated_variable_set)));
+
+ sys->modified = 0;
+}
+
+/* Not a O(1) function */
+
+void lmm_update(lmm_system_t sys, lmm_constraint_t cnst,
+ lmm_variable_t var, double value)
+{
+ int i;
+
+ sys->modified = 1;
+ for (i = 0; i < var->cnsts_number; i++)
+ if (var->cnsts[i].constraint == cnst) {
+ var->cnsts[i].value = value;
+ return;
+ }
+}
+
+void lmm_update_variable_bound(lmm_system_t sys, lmm_variable_t var,
+ double bound)
+{
+ sys->modified = 1;
+ var->bound = bound;
+}
+
+void lmm_update_variable_weight(lmm_system_t sys, lmm_variable_t var,
+ double weight)
+{
+ int i ;
+ lmm_element_t elem;
+
+ sys->modified = 1;
+ var->weight = weight;
+ xbt_swag_remove(var,&(sys->variable_set));
+ if(weight) xbt_swag_insert_at_head(var,&(sys->variable_set));
+ else xbt_swag_insert_at_tail(var,&(sys->variable_set));
+
+ for (i = 0; i < var->cnsts_number; i++) {
+ elem = &var->cnsts[i];
+ xbt_swag_remove(elem, &(elem->constraint->element_set));
+ if(weight) xbt_swag_insert_at_head(elem, &(elem->constraint->element_set));
+ else xbt_swag_insert_at_tail(elem, &(elem->constraint->element_set));
+ }
+}
+
+double lmm_get_variable_weight(lmm_variable_t var)
+
+{
+ return var->weight;
+}
+
+void lmm_update_constraint_bound(lmm_system_t sys, lmm_constraint_t cnst,
+ double bound)
+{
+ sys->modified = 1;
+ cnst->bound = bound;
+}
+
+int lmm_constraint_used(lmm_system_t sys, lmm_constraint_t cnst)
+{
+ return xbt_swag_belongs(cnst, &(sys->active_constraint_set));
+}
+
+lmm_constraint_t lmm_get_first_active_constraint(lmm_system_t sys)
+{
+ return xbt_swag_getFirst(&(sys->active_constraint_set));
+}
+
+lmm_constraint_t lmm_get_next_active_constraint(lmm_system_t sys, lmm_constraint_t cnst)
+{
+ return xbt_swag_getNext(cnst,(sys->active_constraint_set).offset);
+}
+
+
+/* void lmm_print(lmm_system_t sys) */
+/* { */
+/* lmm_variable_t var = NULL; */
+/* lmm_constraint_t cnst = NULL; */
+/* lmm_element_t elem = NULL; */
+/* xbt_swag_t cnst_list = NULL; */
+/* xbt_swag_t var_list = NULL; */
+/* xbt_swag_t elem_list = NULL; */
+/* var_list = &(sys->variable_set); */
+/* xbt_swag_foreach(var, var_list) { */
+/* printf("%s : {\n",var->id); */
+/* printf("\t %s : {\n",var->id); */
+/* } */
+/* } */
