1 /* Copyright (c) 2004-2011. The SimGrid Team.
2 * All rights reserved. */
4 /* This program is free software; you can redistribute it and/or modify it
5 * under the terms of the license (GNU LGPL) which comes with this package. */
8 #include "xbt/sysdep.h"
10 #include "xbt/mallocator.h"
11 #include "maxmin_private.h"
13 #include <stdio.h> /* sprintf */
15 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(surf_maxmin, surf,
16 "Logging specific to SURF (maxmin)");
18 double sg_maxmin_precision = 0.00001;
20 static void *lmm_variable_mallocator_new_f(void);
21 static void lmm_variable_mallocator_free_f(void *var);
22 #define lmm_variable_mallocator_reset_f ((void_f_pvoid_t)NULL)
23 static void lmm_update_modified_set(lmm_system_t sys,
24 lmm_constraint_t cnst);
25 static void lmm_remove_all_modified_set(lmm_system_t sys);
26 static int Global_debug_id = 1;
27 static int Global_const_debug_id = 1;
29 lmm_system_t lmm_system_new(int selective_update)
31 lmm_system_t l = NULL;
33 s_lmm_constraint_t cnst;
35 l = xbt_new0(s_lmm_system_t, 1);
38 l->selective_update_active = selective_update;
39 l->visited_counter = 1;
41 XBT_DEBUG("Setting selective_update_active flag to %d\n",
42 l->selective_update_active);
44 xbt_swag_init(&(l->variable_set),
45 xbt_swag_offset(var, variable_set_hookup));
46 xbt_swag_init(&(l->constraint_set),
47 xbt_swag_offset(cnst, constraint_set_hookup));
49 xbt_swag_init(&(l->active_constraint_set),
50 xbt_swag_offset(cnst, active_constraint_set_hookup));
52 xbt_swag_init(&(l->modified_constraint_set),
53 xbt_swag_offset(cnst, modified_constraint_set_hookup));
54 xbt_swag_init(&(l->saturated_variable_set),
55 xbt_swag_offset(var, saturated_variable_set_hookup));
56 xbt_swag_init(&(l->saturated_constraint_set),
57 xbt_swag_offset(cnst, saturated_constraint_set_hookup));
59 l->variable_mallocator = xbt_mallocator_new(65536,
60 lmm_variable_mallocator_new_f,
61 lmm_variable_mallocator_free_f,
62 lmm_variable_mallocator_reset_f);
67 void lmm_system_free(lmm_system_t sys)
69 lmm_variable_t var = NULL;
70 lmm_constraint_t cnst = NULL;
72 while ((var = extract_variable(sys))) {
74 ("Variable %p (%d) still in LMM system when freing it: this may be a bug",
76 lmm_var_free(sys, var);
79 while ((cnst = extract_constraint(sys)))
80 lmm_cnst_free(sys, cnst);
82 xbt_mallocator_free(sys->variable_mallocator);
86 XBT_INLINE void lmm_variable_disable(lmm_system_t sys, lmm_variable_t var)
91 lmm_element_t elem = NULL;
93 XBT_IN("(sys=%p, var=%p)", sys, var);
97 for (i = 0; i < var->cnsts_number; i++) {
98 elem = &var->cnsts[i];
99 xbt_swag_remove(elem, &(elem->constraint->element_set));
100 xbt_swag_remove(elem, &(elem->constraint->active_element_set));
101 if (!xbt_swag_size(&(elem->constraint->element_set)))
102 make_constraint_inactive(sys, elem->constraint);
105 var->cnsts[n].constraint = elem->constraint;
110 var->cnsts_number = n;
111 lmm_update_modified_set(sys, var->cnsts[0].constraint);
114 var->cnsts_number = 0;
118 static void lmm_var_free(lmm_system_t sys, lmm_variable_t var)
121 lmm_variable_disable(sys, var);
122 xbt_mallocator_release(sys->variable_mallocator, var);
125 static XBT_INLINE void lmm_cnst_free(lmm_system_t sys,
126 lmm_constraint_t cnst)
128 /* xbt_assert(xbt_swag_size(&(cnst->element_set)), */
129 /* "This list should be empty!"); */
130 make_constraint_inactive(sys, cnst);
134 lmm_constraint_t lmm_constraint_new(lmm_system_t sys, void *id,
137 lmm_constraint_t cnst = NULL;
138 s_lmm_element_t elem;
140 cnst = xbt_new0(s_lmm_constraint_t, 1);
142 cnst->id_int = Global_const_debug_id++;
143 xbt_swag_init(&(cnst->element_set),
144 xbt_swag_offset(elem, element_set_hookup));
145 xbt_swag_init(&(cnst->active_element_set),
146 xbt_swag_offset(elem, active_element_set_hookup));
148 cnst->bound = bound_value;
151 insert_constraint(sys, cnst);
156 XBT_INLINE void lmm_constraint_shared(lmm_constraint_t cnst)
161 XBT_INLINE int lmm_constraint_is_shared(lmm_constraint_t cnst)
163 return (cnst->shared);
166 XBT_INLINE void lmm_constraint_free(lmm_system_t sys,
167 lmm_constraint_t cnst)
169 remove_constraint(sys, cnst);
170 lmm_cnst_free(sys, cnst);
173 static void *lmm_variable_mallocator_new_f(void)
175 lmm_variable_t var = xbt_new(s_lmm_variable_t, 1);
176 var->cnsts = NULL; /* will be created by realloc */
180 static void lmm_variable_mallocator_free_f(void *var)
182 xbt_free(((lmm_variable_t) var)->cnsts);
186 lmm_variable_t lmm_variable_new(lmm_system_t sys, void *id,
188 double bound, int number_of_constraints)
190 lmm_variable_t var = NULL;
193 XBT_IN("(sys=%p, id=%p, weight=%f, bound=%f, num_cons =%d)",
194 sys, id, weight, bound, number_of_constraints);
196 var = xbt_mallocator_get(sys->variable_mallocator);
198 var->id_int = Global_debug_id++;
199 var->cnsts = xbt_realloc(var->cnsts, number_of_constraints * sizeof(s_lmm_element_t));
200 for (i = 0; i < number_of_constraints; i++) {
201 var->cnsts[i].element_set_hookup.next = NULL;
202 var->cnsts[i].element_set_hookup.prev = NULL;
203 var->cnsts[i].active_element_set_hookup.next = NULL;
204 var->cnsts[i].active_element_set_hookup.prev = NULL;
205 var->cnsts[i].constraint = NULL;
206 var->cnsts[i].variable = NULL;
207 var->cnsts[i].value = 0.0;
209 var->cnsts_size = number_of_constraints;
210 var->cnsts_number = 0;
211 var->weight = weight;
214 var->visited = sys->visited_counter - 1;
217 var->func_f = func_f_def;
218 var->func_fp = func_fp_def;
219 var->func_fpi = func_fpi_def;
221 var->variable_set_hookup.next = NULL;
222 var->variable_set_hookup.prev = NULL;
223 var->saturated_variable_set_hookup.next = NULL;
224 var->saturated_variable_set_hookup.prev = NULL;
227 xbt_swag_insert_at_head(var, &(sys->variable_set));
229 xbt_swag_insert_at_tail(var, &(sys->variable_set));
234 void lmm_variable_free(lmm_system_t sys, lmm_variable_t var)
236 remove_variable(sys, var);
237 lmm_var_free(sys, var);
240 XBT_INLINE double lmm_variable_getvalue(lmm_variable_t var)
245 XBT_INLINE double lmm_variable_getbound(lmm_variable_t var)
250 void lmm_expand(lmm_system_t sys, lmm_constraint_t cnst,
251 lmm_variable_t var, double value)
253 lmm_element_t elem = NULL;
257 xbt_assert(var->cnsts_number < var->cnsts_size, "Too much constraints");
259 elem = &(var->cnsts[var->cnsts_number++]);
262 elem->constraint = cnst;
263 elem->variable = var;
266 xbt_swag_insert_at_head(elem, &(elem->constraint->element_set));
268 xbt_swag_insert_at_tail(elem, &(elem->constraint->element_set));
270 make_constraint_active(sys, cnst);
271 lmm_update_modified_set(sys, cnst);
272 if (var->cnsts_number > 1)
273 lmm_update_modified_set(sys, var->cnsts[0].constraint);
276 void lmm_expand_add(lmm_system_t sys, lmm_constraint_t cnst,
277 lmm_variable_t var, double value)
282 for (i = 0; i < var->cnsts_number; i++)
283 if (var->cnsts[i].constraint == cnst)
286 if (i < var->cnsts_number) {
288 var->cnsts[i].value += value;
290 var->cnsts[i].value = MAX(var->cnsts[i].value, value);
291 lmm_update_modified_set(sys, cnst);
293 lmm_expand(sys, cnst, var, value);
296 void lmm_elem_set_value(lmm_system_t sys, lmm_constraint_t cnst,
297 lmm_variable_t var, double value)
301 for (i = 0; i < var->cnsts_number; i++)
302 if (var->cnsts[i].constraint == cnst)
305 if (i < var->cnsts_number) {
306 var->cnsts[i].value = value;
308 lmm_update_modified_set(sys, cnst);
313 XBT_INLINE lmm_constraint_t lmm_get_cnst_from_var(lmm_system_t sys,
317 if (num < var->cnsts_number)
318 return (var->cnsts[num].constraint);
323 XBT_INLINE int lmm_get_number_of_cnst_from_var(lmm_system_t sys,
326 return (var->cnsts_number);
329 lmm_variable_t lmm_get_var_from_cnst(lmm_system_t sys,
330 lmm_constraint_t cnst,
331 lmm_element_t * elem)
334 *elem = xbt_swag_getFirst(&(cnst->element_set));
336 *elem = xbt_swag_getNext(*elem, cnst->element_set.offset);
338 return (*elem)->variable;
343 XBT_INLINE void *lmm_constraint_id(lmm_constraint_t cnst)
348 XBT_INLINE void *lmm_variable_id(lmm_variable_t var)
353 static XBT_INLINE void saturated_constraint_set_update(lmm_system_t sys,
358 lmm_constraint_t useless_cnst = NULL;
360 XBT_IN("sys=%p, cnst=%p, min_usage=%f", sys, cnst, *min_usage);
361 if (cnst->usage <= 0) {
365 if (cnst->remaining <= 0) {
369 if ((*min_usage < 0) || (*min_usage > cnst->remaining / cnst->usage)) {
370 *min_usage = cnst->remaining / cnst->usage;
371 XBT_LOG(xbt_log_priority_trace,
372 "min_usage=%f (cnst->remaining=%f, cnst->usage=%f)", *min_usage,
373 cnst->remaining, cnst->usage);
374 while ((useless_cnst =
375 xbt_swag_getFirst(&(sys->saturated_constraint_set))))
376 xbt_swag_remove(useless_cnst, &(sys->saturated_constraint_set));
378 xbt_swag_insert(cnst, &(sys->saturated_constraint_set));
379 } else if (*min_usage == cnst->remaining / cnst->usage) {
380 xbt_swag_insert(cnst, &(sys->saturated_constraint_set));
385 static XBT_INLINE void saturated_variable_set_update(lmm_system_t sys)
387 lmm_constraint_t cnst = NULL;
388 xbt_swag_t cnst_list = NULL;
389 lmm_element_t elem = NULL;
390 xbt_swag_t elem_list = NULL;
392 cnst_list = &(sys->saturated_constraint_set);
393 while ((cnst = xbt_swag_getFirst(cnst_list))) {
394 elem_list = &(cnst->active_element_set);
395 xbt_swag_foreach(elem, elem_list) {
396 if (elem->variable->weight <= 0)
398 if ((elem->value > 0))
399 xbt_swag_insert(elem->variable, &(sys->saturated_variable_set));
401 xbt_swag_remove(cnst, cnst_list);
405 void lmm_print(lmm_system_t sys)
407 lmm_constraint_t cnst = NULL;
408 lmm_element_t elem = NULL;
409 lmm_variable_t var = NULL;
410 xbt_swag_t cnst_list = NULL;
411 xbt_swag_t var_list = NULL;
412 xbt_swag_t elem_list = NULL;
413 char print_buf[1024];
414 char *trace_buf = xbt_malloc0(sizeof(char));
417 /* Printing Objective */
418 var_list = &(sys->variable_set);
419 sprintf(print_buf, "MAX-MIN ( ");
421 xbt_realloc(trace_buf, strlen(trace_buf) + strlen(print_buf) + 1);
422 strcat(trace_buf, print_buf);
423 xbt_swag_foreach(var, var_list) {
424 sprintf(print_buf, "'%d'(%f) ", var->id_int, var->weight);
426 xbt_realloc(trace_buf, strlen(trace_buf) + strlen(print_buf) + 1);
427 strcat(trace_buf, print_buf);
429 sprintf(print_buf, ")");
431 xbt_realloc(trace_buf, strlen(trace_buf) + strlen(print_buf) + 1);
432 strcat(trace_buf, print_buf);
433 XBT_DEBUG("%20s", trace_buf);
434 trace_buf[0] = '\000';
436 XBT_DEBUG("Constraints");
437 /* Printing Constraints */
438 cnst_list = &(sys->active_constraint_set);
439 xbt_swag_foreach(cnst, cnst_list) {
441 elem_list = &(cnst->element_set);
442 sprintf(print_buf, "\t");
444 xbt_realloc(trace_buf, strlen(trace_buf) + strlen(print_buf) + 1);
445 strcat(trace_buf, print_buf);
446 sprintf(print_buf, "%s(",(cnst->shared)?"":"max");
448 xbt_realloc(trace_buf,
449 strlen(trace_buf) + strlen(print_buf) + 1);
450 strcat(trace_buf, print_buf);
451 xbt_swag_foreach(elem, elem_list) {
452 sprintf(print_buf, "%f.'%d'(%f) %s ", elem->value,
453 elem->variable->id_int, elem->variable->value,(cnst->shared)?"+":",");
455 xbt_realloc(trace_buf,
456 strlen(trace_buf) + strlen(print_buf) + 1);
457 strcat(trace_buf, print_buf);
459 sum += elem->value * elem->variable->value;
461 sum = MAX(sum,elem->value * elem->variable->value);
463 sprintf(print_buf, "0) <= %f ('%d')", cnst->bound, cnst->id_int);
465 xbt_realloc(trace_buf, strlen(trace_buf) + strlen(print_buf) + 1);
466 strcat(trace_buf, print_buf);
469 sprintf(print_buf, " [MAX-Constraint]");
471 xbt_realloc(trace_buf,
472 strlen(trace_buf) + strlen(print_buf) + 1);
473 strcat(trace_buf, print_buf);
475 XBT_DEBUG("%s", trace_buf);
476 trace_buf[0] = '\000';
477 xbt_assert(!double_positive(sum - cnst->bound),
478 "Incorrect value (%f is not smaller than %f): %g",
479 sum, cnst->bound, sum - cnst->bound);
482 XBT_DEBUG("Variables");
483 /* Printing Result */
484 xbt_swag_foreach(var, var_list) {
485 if (var->bound > 0) {
486 XBT_DEBUG("'%d'(%f) : %f (<=%f)", var->id_int, var->weight, var->value,
488 xbt_assert(!double_positive(var->value - var->bound),
489 "Incorrect value (%f is not smaller than %f",
490 var->value, var->bound);
492 XBT_DEBUG("'%d'(%f) : %f", var->id_int, var->weight, var->value);
499 void lmm_solve(lmm_system_t sys)
501 lmm_variable_t var = NULL;
502 lmm_constraint_t cnst = NULL;
503 lmm_element_t elem = NULL;
504 xbt_swag_t cnst_list = NULL;
505 xbt_swag_t var_list = NULL;
506 xbt_swag_t elem_list = NULL;
507 double min_usage = -1;
508 double min_bound = -1;
510 if (!(sys->modified))
513 XBT_IN("(sys=%p)", sys);
516 * Compute Usage and store the variables that reach the maximum.
520 selective_update_active ? &(sys->modified_constraint_set) :
521 &(sys->active_constraint_set);
523 XBT_DEBUG("Active constraints : %d", xbt_swag_size(cnst_list));
524 /* Init: Only modified code portions */
525 xbt_swag_foreach(cnst, cnst_list) {
526 elem_list = &(cnst->element_set);
527 //XBT_DEBUG("Variable set : %d", xbt_swag_size(elem_list));
528 xbt_swag_foreach(elem, elem_list) {
529 var = elem->variable;
530 if (var->weight <= 0.0)
536 xbt_swag_foreach(cnst, cnst_list) {
538 cnst->remaining = cnst->bound;
539 if (cnst->remaining == 0)
542 elem_list = &(cnst->element_set);
543 xbt_swag_foreach(elem, elem_list) {
544 /* 0-weighted elements (ie, sleep actions) are at the end of the swag and we don't want to consider them */
545 if (elem->variable->weight <= 0)
547 if ((elem->value > 0)) {
549 cnst->usage += elem->value / elem->variable->weight;
550 else if (cnst->usage < elem->value / elem->variable->weight)
551 cnst->usage = elem->value / elem->variable->weight;
553 make_elem_active(elem);
555 xbt_swag_insert(elem->variable->id, sys->keep_track);
558 XBT_DEBUG("Constraint Usage '%d' : %f", cnst->id_int, cnst->usage);
559 /* Saturated constraints update */
560 saturated_constraint_set_update(sys, cnst, &min_usage);
562 saturated_variable_set_update(sys);
564 /* Saturated variables update */
567 /* Fix the variables that have to be */
568 var_list = &(sys->saturated_variable_set);
570 xbt_swag_foreach(var, var_list) {
571 if (var->weight <= 0.0)
573 /* First check if some of these variables have reach their upper
574 bound and update min_usage accordingly. */
576 ("var=%d, var->bound=%f, var->weight=%f, min_usage=%f, var->bound*var->weight=%f",
577 var->id_int, var->bound, var->weight, min_usage,
578 var->bound * var->weight);
579 if ((var->bound > 0) && (var->bound * var->weight < min_usage)) {
581 min_bound = var->bound;
583 min_bound = MIN(min_bound, var->bound);
584 XBT_DEBUG("Updated min_bound=%f", min_bound);
589 while ((var = xbt_swag_getFirst(var_list))) {
593 var->value = min_usage / var->weight;
595 if (min_bound == var->bound)
596 var->value = var->bound;
598 xbt_swag_remove(var, var_list);
602 XBT_DEBUG("Min usage: %f, Var(%d)->weight: %f, Var(%d)->value: %f ",
603 min_usage, var->id_int, var->weight, var->id_int, var->value);
608 for (i = 0; i < var->cnsts_number; i++) {
609 elem = &var->cnsts[i];
610 cnst = elem->constraint;
612 double_update(&(cnst->remaining), elem->value * var->value);
613 double_update(&(cnst->usage), elem->value / var->weight);
614 make_elem_inactive(elem);
615 } else { /* FIXME one day: We recompute usage.... :( */
617 make_elem_inactive(elem);
618 elem_list = &(cnst->element_set);
619 xbt_swag_foreach(elem, elem_list) {
620 if (elem->variable->weight <= 0)
622 if (elem->variable->value > 0)
624 if ((elem->value > 0)) {
626 MAX(cnst->usage, elem->value / elem->variable->weight);
627 XBT_DEBUG("Constraint Usage %d : %f", cnst->id_int,
629 make_elem_active(elem);
634 xbt_swag_remove(var, var_list);
637 /* Find out which variables reach the maximum */
640 xbt_swag_foreach(cnst, cnst_list) {
641 saturated_constraint_set_update(sys, cnst, &min_usage);
643 saturated_variable_set_update(sys);
645 } while (xbt_swag_size(&(sys->saturated_variable_set)));
648 if (sys->selective_update_active)
649 lmm_remove_all_modified_set(sys);
651 if (XBT_LOG_ISENABLED(surf_maxmin, xbt_log_priority_debug)) {
657 /* Not a O(1) function */
659 void lmm_update(lmm_system_t sys, lmm_constraint_t cnst,
660 lmm_variable_t var, double value)
664 for (i = 0; i < var->cnsts_number; i++)
665 if (var->cnsts[i].constraint == cnst) {
666 var->cnsts[i].value = value;
668 lmm_update_modified_set(sys, cnst);
673 /** \brief Attribute the value bound to var->bound.
675 * \param sys the lmm_system_t
676 * \param var the lmm_variable_t
677 * \param bound the new bound to associate with var
679 * Makes var->bound equal to bound. Whenever this function is called
680 * a change is signed in the system. To
681 * avoid false system changing detection it is a good idea to test
682 * (bound != 0) before calling it.
685 void lmm_update_variable_bound(lmm_system_t sys, lmm_variable_t var,
691 if (var->cnsts_number)
692 lmm_update_modified_set(sys, var->cnsts[0].constraint);
696 void lmm_update_variable_weight(lmm_system_t sys, lmm_variable_t var,
702 if (weight == var->weight)
704 XBT_IN("(sys=%p, var=%p, weight=%f)", sys, var, weight);
706 var->weight = weight;
707 xbt_swag_remove(var, &(sys->variable_set));
709 xbt_swag_insert_at_head(var, &(sys->variable_set));
711 xbt_swag_insert_at_tail(var, &(sys->variable_set));
713 for (i = 0; i < var->cnsts_number; i++) {
714 elem = &var->cnsts[i];
715 xbt_swag_remove(elem, &(elem->constraint->element_set));
717 xbt_swag_insert_at_head(elem, &(elem->constraint->element_set));
719 xbt_swag_insert_at_tail(elem, &(elem->constraint->element_set));
722 lmm_update_modified_set(sys, elem->constraint);
730 XBT_INLINE double lmm_get_variable_weight(lmm_variable_t var)
735 XBT_INLINE void lmm_update_constraint_bound(lmm_system_t sys,
736 lmm_constraint_t cnst,
740 lmm_update_modified_set(sys, cnst);
744 XBT_INLINE int lmm_constraint_used(lmm_system_t sys, lmm_constraint_t cnst)
746 return xbt_swag_belongs(cnst, &(sys->active_constraint_set));
749 XBT_INLINE lmm_constraint_t lmm_get_first_active_constraint(lmm_system_t
752 return xbt_swag_getFirst(&(sys->active_constraint_set));
755 XBT_INLINE lmm_constraint_t lmm_get_next_active_constraint(lmm_system_t
760 return xbt_swag_getNext(cnst, (sys->active_constraint_set).offset);
763 #ifdef HAVE_LATENCY_BOUND_TRACKING
764 XBT_INLINE int lmm_is_variable_limited_by_latency(lmm_variable_t var)
766 return (double_equals(var->bound, var->value));
771 /** \brief Update the constraint set propagating recursively to
772 * other constraints so the system should not be entirely computed.
774 * \param sys the lmm_system_t
775 * \param cnst the lmm_constraint_t affected by the change
777 * A recursive algorithm to optimize the system recalculation selecting only
778 * constraints that have changed. Each constraint change is propagated
779 * to the list of constraints for each variable.
781 static void lmm_update_modified_set_rec(lmm_system_t sys,
782 lmm_constraint_t cnst)
786 xbt_swag_foreach(elem, &cnst->element_set) {
787 lmm_variable_t var = elem->variable;
788 s_lmm_element_t *cnsts = var->cnsts;
790 for (i = 0; var->visited != sys->visited_counter
791 && i < var->cnsts_number ; i++) {
792 if (cnsts[i].constraint != cnst
793 && !xbt_swag_belongs(cnsts[i].constraint,
794 &sys->modified_constraint_set)) {
795 xbt_swag_insert(cnsts[i].constraint, &sys->modified_constraint_set);
796 lmm_update_modified_set_rec(sys, cnsts[i].constraint);
799 var->visited = sys->visited_counter;
803 static void lmm_update_modified_set(lmm_system_t sys,
804 lmm_constraint_t cnst)
806 /* nothing to do if selective update isn't active */
807 if (sys->selective_update_active
808 && !xbt_swag_belongs(cnst, &sys->modified_constraint_set)) {
809 xbt_swag_insert(cnst, &sys->modified_constraint_set);
810 lmm_update_modified_set_rec(sys, cnst);
814 /** \brief Remove all constraints of the modified_constraint_set.
816 * \param sys the lmm_system_t
818 static void lmm_remove_all_modified_set(lmm_system_t sys)
820 if (++sys->visited_counter == 1) {
821 /* the counter wrapped around, reset each variable->visited */
823 xbt_swag_foreach(var, &sys->variable_set)
826 xbt_swag_reset(&sys->modified_constraint_set);