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;
28 extern xbt_swag_t keep_track;
30 lmm_system_t lmm_system_new(int selective_update)
32 lmm_system_t l = NULL;
34 s_lmm_constraint_t cnst;
36 l = xbt_new0(s_lmm_system_t, 1);
39 l->selective_update_active = selective_update;
40 l->visited_counter = 1;
42 XBT_DEBUG("Setting selective_update_active flag to %d\n",
43 l->selective_update_active);
45 xbt_swag_init(&(l->variable_set),
46 xbt_swag_offset(var, variable_set_hookup));
47 xbt_swag_init(&(l->constraint_set),
48 xbt_swag_offset(cnst, constraint_set_hookup));
50 xbt_swag_init(&(l->active_constraint_set),
51 xbt_swag_offset(cnst, active_constraint_set_hookup));
53 xbt_swag_init(&(l->modified_constraint_set),
54 xbt_swag_offset(cnst, modified_constraint_set_hookup));
55 xbt_swag_init(&(l->saturated_variable_set),
56 xbt_swag_offset(var, saturated_variable_set_hookup));
57 xbt_swag_init(&(l->saturated_constraint_set),
58 xbt_swag_offset(cnst, saturated_constraint_set_hookup));
60 l->variable_mallocator = xbt_mallocator_new(65536,
61 lmm_variable_mallocator_new_f,
62 lmm_variable_mallocator_free_f,
63 lmm_variable_mallocator_reset_f);
68 void lmm_system_free(lmm_system_t sys)
70 lmm_variable_t var = NULL;
71 lmm_constraint_t cnst = NULL;
73 while ((var = extract_variable(sys))) {
75 ("Variable %p (%d) still in LMM system when freing it: this may be a bug",
77 lmm_var_free(sys, var);
80 while ((cnst = extract_constraint(sys)))
81 lmm_cnst_free(sys, cnst);
83 xbt_mallocator_free(sys->variable_mallocator);
87 XBT_INLINE void lmm_variable_disable(lmm_system_t sys, lmm_variable_t var)
92 lmm_element_t elem = NULL;
94 XBT_IN("(sys=%p, var=%p)", sys, var);
98 for (i = 0; i < var->cnsts_number; i++) {
99 elem = &var->cnsts[i];
100 xbt_swag_remove(elem, &(elem->constraint->element_set));
101 xbt_swag_remove(elem, &(elem->constraint->active_element_set));
102 if (!xbt_swag_size(&(elem->constraint->element_set)))
103 make_constraint_inactive(sys, elem->constraint);
106 var->cnsts[n].constraint = elem->constraint;
111 var->cnsts_number = n;
112 lmm_update_modified_set(sys, var->cnsts[0].constraint);
115 var->cnsts_number = 0;
119 static void lmm_var_free(lmm_system_t sys, lmm_variable_t var)
122 lmm_variable_disable(sys, var);
123 xbt_mallocator_release(sys->variable_mallocator, var);
126 static XBT_INLINE void lmm_cnst_free(lmm_system_t sys,
127 lmm_constraint_t cnst)
129 /* xbt_assert(xbt_swag_size(&(cnst->element_set)), */
130 /* "This list should be empty!"); */
131 make_constraint_inactive(sys, cnst);
135 lmm_constraint_t lmm_constraint_new(lmm_system_t sys, void *id,
138 lmm_constraint_t cnst = NULL;
139 s_lmm_element_t elem;
141 cnst = xbt_new0(s_lmm_constraint_t, 1);
143 cnst->id_int = Global_const_debug_id++;
144 xbt_swag_init(&(cnst->element_set),
145 xbt_swag_offset(elem, element_set_hookup));
146 xbt_swag_init(&(cnst->active_element_set),
147 xbt_swag_offset(elem, active_element_set_hookup));
149 cnst->bound = bound_value;
152 insert_constraint(sys, cnst);
157 XBT_INLINE void lmm_constraint_shared(lmm_constraint_t cnst)
162 XBT_INLINE int lmm_constraint_is_shared(lmm_constraint_t cnst)
164 return (cnst->shared);
167 XBT_INLINE void lmm_constraint_free(lmm_system_t sys,
168 lmm_constraint_t cnst)
170 remove_constraint(sys, cnst);
171 lmm_cnst_free(sys, cnst);
174 static void *lmm_variable_mallocator_new_f(void)
176 lmm_variable_t var = xbt_new(s_lmm_variable_t, 1);
177 var->cnsts = NULL; /* will be created by realloc */
181 static void lmm_variable_mallocator_free_f(void *var)
183 xbt_free(((lmm_variable_t) var)->cnsts);
187 lmm_variable_t lmm_variable_new(lmm_system_t sys, void *id,
189 double bound, int number_of_constraints)
191 lmm_variable_t var = NULL;
194 XBT_IN("(sys=%p, id=%p, weight=%f, bound=%f, num_cons =%d)",
195 sys, id, weight, bound, number_of_constraints);
197 var = xbt_mallocator_get(sys->variable_mallocator);
199 var->id_int = Global_debug_id++;
200 var->cnsts = xbt_realloc(var->cnsts, number_of_constraints * sizeof(s_lmm_element_t));
201 for (i = 0; i < number_of_constraints; i++) {
202 var->cnsts[i].element_set_hookup.next = NULL;
203 var->cnsts[i].element_set_hookup.prev = NULL;
204 var->cnsts[i].active_element_set_hookup.next = NULL;
205 var->cnsts[i].active_element_set_hookup.prev = NULL;
206 var->cnsts[i].constraint = NULL;
207 var->cnsts[i].variable = NULL;
208 var->cnsts[i].value = 0.0;
210 var->cnsts_size = number_of_constraints;
211 var->cnsts_number = 0;
212 var->weight = weight;
215 var->visited = sys->visited_counter - 1;
218 var->func_f = func_f_def;
219 var->func_fp = func_fp_def;
220 var->func_fpi = func_fpi_def;
222 var->variable_set_hookup.next = NULL;
223 var->variable_set_hookup.prev = NULL;
224 var->saturated_variable_set_hookup.next = NULL;
225 var->saturated_variable_set_hookup.prev = NULL;
228 xbt_swag_insert_at_head(var, &(sys->variable_set));
230 xbt_swag_insert_at_tail(var, &(sys->variable_set));
235 void lmm_variable_free(lmm_system_t sys, lmm_variable_t var)
237 remove_variable(sys, var);
238 lmm_var_free(sys, var);
241 XBT_INLINE double lmm_variable_getvalue(lmm_variable_t var)
246 XBT_INLINE double lmm_variable_getbound(lmm_variable_t var)
251 void lmm_expand(lmm_system_t sys, lmm_constraint_t cnst,
252 lmm_variable_t var, double value)
254 lmm_element_t elem = NULL;
258 xbt_assert(var->cnsts_number < var->cnsts_size, "Too much constraints");
260 elem = &(var->cnsts[var->cnsts_number++]);
263 elem->constraint = cnst;
264 elem->variable = var;
267 xbt_swag_insert_at_head(elem, &(elem->constraint->element_set));
269 xbt_swag_insert_at_tail(elem, &(elem->constraint->element_set));
271 make_constraint_active(sys, cnst);
272 lmm_update_modified_set(sys, cnst);
273 if (var->cnsts_number > 1)
274 lmm_update_modified_set(sys, var->cnsts[0].constraint);
277 void lmm_expand_add(lmm_system_t sys, lmm_constraint_t cnst,
278 lmm_variable_t var, double value)
283 for (i = 0; i < var->cnsts_number; i++)
284 if (var->cnsts[i].constraint == cnst)
287 if (i < var->cnsts_number) {
289 var->cnsts[i].value += value;
291 var->cnsts[i].value = MAX(var->cnsts[i].value, value);
292 lmm_update_modified_set(sys, cnst);
294 lmm_expand(sys, cnst, var, value);
297 void lmm_elem_set_value(lmm_system_t sys, lmm_constraint_t cnst,
298 lmm_variable_t var, double value)
302 for (i = 0; i < var->cnsts_number; i++)
303 if (var->cnsts[i].constraint == cnst)
306 if (i < var->cnsts_number) {
307 var->cnsts[i].value = value;
309 lmm_update_modified_set(sys, cnst);
314 XBT_INLINE lmm_constraint_t lmm_get_cnst_from_var(lmm_system_t sys,
318 if (num < var->cnsts_number)
319 return (var->cnsts[num].constraint);
324 XBT_INLINE int lmm_get_number_of_cnst_from_var(lmm_system_t sys,
327 return (var->cnsts_number);
330 lmm_variable_t lmm_get_var_from_cnst(lmm_system_t sys,
331 lmm_constraint_t cnst,
332 lmm_element_t * elem)
335 *elem = xbt_swag_getFirst(&(cnst->element_set));
337 *elem = xbt_swag_getNext(*elem, cnst->element_set.offset);
339 return (*elem)->variable;
344 XBT_INLINE void *lmm_constraint_id(lmm_constraint_t cnst)
349 XBT_INLINE void *lmm_variable_id(lmm_variable_t var)
354 static XBT_INLINE void saturated_constraint_set_update(lmm_system_t sys,
359 lmm_constraint_t useless_cnst = NULL;
361 XBT_IN("sys=%p, cnst=%p, min_usage=%f", sys, cnst, *min_usage);
362 if (cnst->usage <= 0) {
366 if (cnst->remaining <= 0) {
370 if ((*min_usage < 0) || (*min_usage > cnst->remaining / cnst->usage)) {
371 *min_usage = cnst->remaining / cnst->usage;
372 XBT_LOG(xbt_log_priority_trace,
373 "min_usage=%f (cnst->remaining=%f, cnst->usage=%f)", *min_usage,
374 cnst->remaining, cnst->usage);
375 while ((useless_cnst =
376 xbt_swag_getFirst(&(sys->saturated_constraint_set))))
377 xbt_swag_remove(useless_cnst, &(sys->saturated_constraint_set));
379 xbt_swag_insert(cnst, &(sys->saturated_constraint_set));
380 } else if (*min_usage == cnst->remaining / cnst->usage) {
381 xbt_swag_insert(cnst, &(sys->saturated_constraint_set));
386 static XBT_INLINE void saturated_variable_set_update(lmm_system_t sys)
388 lmm_constraint_t cnst = NULL;
389 xbt_swag_t cnst_list = NULL;
390 lmm_element_t elem = NULL;
391 xbt_swag_t elem_list = NULL;
393 cnst_list = &(sys->saturated_constraint_set);
394 while ((cnst = xbt_swag_getFirst(cnst_list))) {
395 elem_list = &(cnst->active_element_set);
396 xbt_swag_foreach(elem, elem_list) {
397 if (elem->variable->weight <= 0)
399 if ((elem->value > 0))
400 xbt_swag_insert(elem->variable, &(sys->saturated_variable_set));
402 xbt_swag_remove(cnst, cnst_list);
406 void lmm_print(lmm_system_t sys)
408 lmm_constraint_t cnst = NULL;
409 lmm_element_t elem = NULL;
410 lmm_variable_t var = NULL;
411 xbt_swag_t cnst_list = NULL;
412 xbt_swag_t var_list = NULL;
413 xbt_swag_t elem_list = NULL;
414 char print_buf[1024];
415 char *trace_buf = xbt_malloc0(sizeof(char));
418 /* Printing Objective */
419 var_list = &(sys->variable_set);
420 sprintf(print_buf, "MAX-MIN ( ");
422 xbt_realloc(trace_buf, strlen(trace_buf) + strlen(print_buf) + 1);
423 strcat(trace_buf, print_buf);
424 xbt_swag_foreach(var, var_list) {
425 sprintf(print_buf, "'%d'(%f) ", var->id_int, var->weight);
427 xbt_realloc(trace_buf, strlen(trace_buf) + strlen(print_buf) + 1);
428 strcat(trace_buf, print_buf);
430 sprintf(print_buf, ")");
432 xbt_realloc(trace_buf, strlen(trace_buf) + strlen(print_buf) + 1);
433 strcat(trace_buf, print_buf);
434 XBT_DEBUG("%20s", trace_buf);
435 trace_buf[0] = '\000';
437 XBT_DEBUG("Constraints");
438 /* Printing Constraints */
439 cnst_list = &(sys->active_constraint_set);
440 xbt_swag_foreach(cnst, cnst_list) {
442 elem_list = &(cnst->element_set);
443 sprintf(print_buf, "\t");
445 xbt_realloc(trace_buf, strlen(trace_buf) + strlen(print_buf) + 1);
446 strcat(trace_buf, print_buf);
447 sprintf(print_buf, "%s(",(cnst->shared)?"":"max");
449 xbt_realloc(trace_buf,
450 strlen(trace_buf) + strlen(print_buf) + 1);
451 strcat(trace_buf, print_buf);
452 xbt_swag_foreach(elem, elem_list) {
453 sprintf(print_buf, "%f.'%d'(%f) %s ", elem->value,
454 elem->variable->id_int, elem->variable->value,(cnst->shared)?"+":",");
456 xbt_realloc(trace_buf,
457 strlen(trace_buf) + strlen(print_buf) + 1);
458 strcat(trace_buf, print_buf);
460 sum += elem->value * elem->variable->value;
462 sum = MAX(sum,elem->value * elem->variable->value);
464 sprintf(print_buf, "0) <= %f ('%d')", cnst->bound, cnst->id_int);
466 xbt_realloc(trace_buf, strlen(trace_buf) + strlen(print_buf) + 1);
467 strcat(trace_buf, print_buf);
470 sprintf(print_buf, " [MAX-Constraint]");
472 xbt_realloc(trace_buf,
473 strlen(trace_buf) + strlen(print_buf) + 1);
474 strcat(trace_buf, print_buf);
476 XBT_DEBUG("%s", trace_buf);
477 trace_buf[0] = '\000';
478 xbt_assert(!double_positive(sum - cnst->bound),
479 "Incorrect value (%f is not smaller than %f): %g",
480 sum, cnst->bound, sum - cnst->bound);
483 XBT_DEBUG("Variables");
484 /* Printing Result */
485 xbt_swag_foreach(var, var_list) {
486 if (var->bound > 0) {
487 XBT_DEBUG("'%d'(%f) : %f (<=%f)", var->id_int, var->weight, var->value,
489 xbt_assert(!double_positive(var->value - var->bound),
490 "Incorrect value (%f is not smaller than %f",
491 var->value, var->bound);
493 XBT_DEBUG("'%d'(%f) : %f", var->id_int, var->weight, var->value);
500 void lmm_solve(lmm_system_t sys)
502 lmm_variable_t var = NULL;
503 lmm_constraint_t cnst = NULL;
504 lmm_element_t elem = NULL;
505 xbt_swag_t cnst_list = NULL;
506 xbt_swag_t var_list = NULL;
507 xbt_swag_t elem_list = NULL;
508 double min_usage = -1;
509 double min_bound = -1;
511 if (!(sys->modified))
514 XBT_IN("(sys=%p)", sys);
517 * Compute Usage and store the variables that reach the maximum.
521 selective_update_active ? &(sys->modified_constraint_set) :
522 &(sys->active_constraint_set);
524 XBT_DEBUG("Active constraints : %d", xbt_swag_size(cnst_list));
525 /* Init: Only modified code portions */
526 xbt_swag_foreach(cnst, cnst_list) {
527 elem_list = &(cnst->element_set);
528 //XBT_DEBUG("Variable set : %d", xbt_swag_size(elem_list));
529 xbt_swag_foreach(elem, elem_list) {
530 var = elem->variable;
531 if (var->weight <= 0.0)
537 xbt_swag_foreach(cnst, cnst_list) {
539 cnst->remaining = cnst->bound;
540 if (cnst->remaining == 0)
543 elem_list = &(cnst->element_set);
544 xbt_swag_foreach(elem, elem_list) {
545 /* 0-weighted elements (ie, sleep actions) are at the end of the swag and we don't want to consider them */
546 if (elem->variable->weight <= 0)
548 if ((elem->value > 0)) {
550 cnst->usage += elem->value / elem->variable->weight;
551 else if (cnst->usage < elem->value / elem->variable->weight)
552 cnst->usage = elem->value / elem->variable->weight;
554 make_elem_active(elem);
556 xbt_swag_insert((elem->variable)->id, keep_track);
560 XBT_DEBUG("Constraint Usage '%d' : %f", cnst->id_int, cnst->usage);
561 /* Saturated constraints update */
562 saturated_constraint_set_update(sys, cnst, &min_usage);
564 saturated_variable_set_update(sys);
566 /* Saturated variables update */
569 /* Fix the variables that have to be */
570 var_list = &(sys->saturated_variable_set);
572 xbt_swag_foreach(var, var_list) {
573 if (var->weight <= 0.0)
575 /* First check if some of these variables have reach their upper
576 bound and update min_usage accordingly. */
578 ("var=%d, var->bound=%f, var->weight=%f, min_usage=%f, var->bound*var->weight=%f",
579 var->id_int, var->bound, var->weight, min_usage,
580 var->bound * var->weight);
581 if ((var->bound > 0) && (var->bound * var->weight < min_usage)) {
583 min_bound = var->bound;
585 min_bound = MIN(min_bound, var->bound);
586 XBT_DEBUG("Updated min_bound=%f", min_bound);
591 while ((var = xbt_swag_getFirst(var_list))) {
595 var->value = min_usage / var->weight;
597 if (min_bound == var->bound)
598 var->value = var->bound;
600 xbt_swag_remove(var, var_list);
604 XBT_DEBUG("Min usage: %f, Var(%d)->weight: %f, Var(%d)->value: %f ",
605 min_usage, var->id_int, var->weight, var->id_int, var->value);
610 for (i = 0; i < var->cnsts_number; i++) {
611 elem = &var->cnsts[i];
612 cnst = elem->constraint;
614 double_update(&(cnst->remaining), elem->value * var->value);
615 double_update(&(cnst->usage), elem->value / var->weight);
616 make_elem_inactive(elem);
617 } else { /* FIXME one day: We recompute usage.... :( */
619 make_elem_inactive(elem);
620 elem_list = &(cnst->element_set);
621 xbt_swag_foreach(elem, elem_list) {
622 if (elem->variable->weight <= 0)
624 if (elem->variable->value > 0)
626 if ((elem->value > 0)) {
628 MAX(cnst->usage, elem->value / elem->variable->weight);
629 XBT_DEBUG("Constraint Usage %d : %f", cnst->id_int,
631 make_elem_active(elem);
636 xbt_swag_remove(var, var_list);
639 /* Find out which variables reach the maximum */
642 xbt_swag_foreach(cnst, cnst_list) {
643 saturated_constraint_set_update(sys, cnst, &min_usage);
645 saturated_variable_set_update(sys);
647 } while (xbt_swag_size(&(sys->saturated_variable_set)));
650 if (sys->selective_update_active)
651 lmm_remove_all_modified_set(sys);
653 if (XBT_LOG_ISENABLED(surf_maxmin, xbt_log_priority_debug)) {
659 /* Not a O(1) function */
661 void lmm_update(lmm_system_t sys, lmm_constraint_t cnst,
662 lmm_variable_t var, double value)
666 for (i = 0; i < var->cnsts_number; i++)
667 if (var->cnsts[i].constraint == cnst) {
668 var->cnsts[i].value = value;
670 lmm_update_modified_set(sys, cnst);
675 /** \brief Attribute the value bound to var->bound.
677 * \param sys the lmm_system_t
678 * \param var the lmm_variable_t
679 * \param bound the new bound to associate with var
681 * Makes var->bound equal to bound. Whenever this function is called
682 * a change is signed in the system. To
683 * avoid false system changing detection it is a good idea to test
684 * (bound != 0) before calling it.
687 void lmm_update_variable_bound(lmm_system_t sys, lmm_variable_t var,
693 if (var->cnsts_number)
694 lmm_update_modified_set(sys, var->cnsts[0].constraint);
698 void lmm_update_variable_weight(lmm_system_t sys, lmm_variable_t var,
704 if (weight == var->weight)
706 XBT_IN("(sys=%p, var=%p, weight=%f)", sys, var, weight);
708 var->weight = weight;
709 xbt_swag_remove(var, &(sys->variable_set));
711 xbt_swag_insert_at_head(var, &(sys->variable_set));
713 xbt_swag_insert_at_tail(var, &(sys->variable_set));
715 for (i = 0; i < var->cnsts_number; i++) {
716 elem = &var->cnsts[i];
717 xbt_swag_remove(elem, &(elem->constraint->element_set));
719 xbt_swag_insert_at_head(elem, &(elem->constraint->element_set));
721 xbt_swag_insert_at_tail(elem, &(elem->constraint->element_set));
724 lmm_update_modified_set(sys, elem->constraint);
732 XBT_INLINE double lmm_get_variable_weight(lmm_variable_t var)
737 XBT_INLINE void lmm_update_constraint_bound(lmm_system_t sys,
738 lmm_constraint_t cnst,
742 lmm_update_modified_set(sys, cnst);
746 XBT_INLINE int lmm_constraint_used(lmm_system_t sys, lmm_constraint_t cnst)
748 return xbt_swag_belongs(cnst, &(sys->active_constraint_set));
751 XBT_INLINE lmm_constraint_t lmm_get_first_active_constraint(lmm_system_t
754 return xbt_swag_getFirst(&(sys->active_constraint_set));
757 XBT_INLINE lmm_constraint_t lmm_get_next_active_constraint(lmm_system_t
762 return xbt_swag_getNext(cnst, (sys->active_constraint_set).offset);
765 #ifdef HAVE_LATENCY_BOUND_TRACKING
766 XBT_INLINE int lmm_is_variable_limited_by_latency(lmm_variable_t var)
768 return (double_equals(var->bound, var->value));
773 /** \brief Update the constraint set propagating recursively to
774 * other constraints so the system should not be entirely computed.
776 * \param sys the lmm_system_t
777 * \param cnst the lmm_constraint_t affected by the change
779 * A recursive algorithm to optimize the system recalculation selecting only
780 * constraints that have changed. Each constraint change is propagated
781 * to the list of constraints for each variable.
783 static void lmm_update_modified_set_rec(lmm_system_t sys,
784 lmm_constraint_t cnst)
788 xbt_swag_foreach(elem, &cnst->element_set) {
789 lmm_variable_t var = elem->variable;
790 s_lmm_element_t *cnsts = var->cnsts;
792 for (i = 0; var->visited != sys->visited_counter
793 && i < var->cnsts_number ; i++) {
794 if (cnsts[i].constraint != cnst
795 && !xbt_swag_belongs(cnsts[i].constraint,
796 &sys->modified_constraint_set)) {
797 xbt_swag_insert(cnsts[i].constraint, &sys->modified_constraint_set);
798 lmm_update_modified_set_rec(sys, cnsts[i].constraint);
801 var->visited = sys->visited_counter;
805 static void lmm_update_modified_set(lmm_system_t sys,
806 lmm_constraint_t cnst)
808 /* nothing to do if selective update isn't active */
809 if (sys->selective_update_active
810 && !xbt_swag_belongs(cnst, &sys->modified_constraint_set)) {
811 xbt_swag_insert(cnst, &sys->modified_constraint_set);
812 lmm_update_modified_set_rec(sys, cnst);
816 /** \brief Remove all constraints of the modified_constraint_set.
818 * \param sys the lmm_system_t
820 static void lmm_remove_all_modified_set(lmm_system_t sys)
822 if (++sys->visited_counter == 1) {
823 /* the counter wrapped around, reset each variable->visited */
825 xbt_swag_foreach(var, &sys->variable_set)
828 xbt_swag_reset(&sys->modified_constraint_set);