+/* $Id$ */
+
+/* Copyright (c) 2007 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. */
+
+
+#include "xbt/sysdep.h"
+#include "xbt/log.h"
+#include "maxmin_private.h"
+#include <stdlib.h>
+#include <math.h>
+
+XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(surf_maxmin);
+
+void bottleneck_solve(lmm_system_t sys)
+{
+ lmm_variable_t var = NULL;
+ lmm_constraint_t cnst = NULL;
+ lmm_constraint_t useless_cnst = NULL;
+ s_lmm_constraint_t s_cnst;
+ lmm_constraint_t cnst_next = 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;
+
+ static s_xbt_swag_t cnst_to_update;
+
+
+ if (!(sys->modified))
+ return;
+
+ /* Init */
+ xbt_swag_init(&(cnst_to_update),
+ xbt_swag_offset(s_cnst, saturated_constraint_set_hookup));
+
+ var_list = &(sys->variable_set);
+ DEBUG1("Variable set : %d", xbt_swag_size(var_list));
+ xbt_swag_foreach(var, var_list) {
+ var->value = 0.0;
+ }
+
+ cnst_list = &(sys->active_constraint_set);
+ DEBUG1("Active constraints : %d", xbt_swag_size(cnst_list));
+ xbt_swag_foreach(cnst, cnst_list) {
+ xbt_swag_insert(cnst, &(sys->saturated_constraint_set));
+ }
+ cnst_list = &(sys->saturated_constraint_set);
+ xbt_swag_foreach(cnst, cnst_list) {
+ cnst->remaining = cnst->bound;
+ cnst->usage = 0.0;
+ }
+
+ /*
+ * Compute Usage and store the variables that reach the maximum.
+ */
+ while(1){
+ DEBUG1("Constraints to process: %d", xbt_swag_size(cnst_list));
+ xbt_swag_foreach_safe(cnst, cnst_next, cnst_list) {
+ int nb = 0;
+ elem_list = &(cnst->element_set);
+ cnst->usage = 0.0;
+ if(!cnst->shared) DIE_IMPOSSIBLE;
+ xbt_swag_foreach(elem, elem_list) {
+ if(elem->variable->weight <=0) break;
+ if ((elem->value > 0)) {
+ nb++;
+ if(cnst->usage>0)
+ cnst->usage = MIN(cnst->usage, elem->value / elem->variable->weight);
+ else
+ cnst->usage = elem->value / elem->variable->weight;
+ }
+ DEBUG2("Constraint Usage %p : %f",cnst,cnst->usage);
+ // make_elem_active(elem);
+ }
+ cnst->usage = cnst->usage * nb;
+ /* Saturated constraints update */
+ if(min_usage<0 || min_usage > cnst->remaining / cnst->usage) {
+ min_usage = cnst->remaining / cnst->usage;
+ while ((useless_cnst = xbt_swag_extract(&(cnst_to_update)))) {
+ xbt_swag_insert_at_head(useless_cnst, cnst_list);
+ }
+ xbt_swag_remove(cnst, cnst_list);
+ xbt_swag_insert(cnst, &(cnst_to_update));
+ } else if (min_usage == cnst->remaining / cnst->usage) {
+ xbt_swag_remove(cnst, cnst_list);
+ xbt_swag_insert(cnst, &(cnst_to_update));
+ }
+ }
+
+ if(!xbt_swag_size(&cnst_to_update)) break;
+
+ while((cnst = xbt_swag_extract(&cnst_to_update))) {
+ int nb = 0;
+ xbt_swag_foreach(elem, elem_list) {
+ if(elem->variable->weight <=0) break;
+ if ((elem->value > 0)) nb++;
+ }
+ xbt_swag_foreach(elem, elem_list) {
+ var=elem->variable;
+ if(var->weight <=0) break;
+ if(var->value == 0.0) {
+ int i;
+ var->value = cnst->remaining / nb * var->weight /
+ elem->value;
+
+ /* Update usage */
+
+ for (i = 0; i < var->cnsts_number; i++) {
+ lmm_element_t elm = &var->cnsts[i];
+ cnst = elm->constraint;
+ double_update(&(cnst->remaining), elm->value * var->value);
+ double_update(&(cnst->usage), elm->value / var->weight);
+ // make_elem_inactive(elm);
+ }
+ }
+ }
+ }
+ }
+
+ sys->modified = 0;
+ if(XBT_LOG_ISENABLED(surf_maxmin, xbt_log_priority_debug)) {
+ lmm_print(sys);
+ }
+}
+
