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 int sg_maxmin_selective_update = 1;
27 static int Global_debug_id = 1;
28 static int Global_const_debug_id = 1;
29 extern xbt_swag_t keep_track;
31 lmm_system_t lmm_system_new(void)
33 lmm_system_t l = NULL;
35 s_lmm_constraint_t cnst;
37 l = xbt_new0(s_lmm_system_t, 1);
40 l->selective_update_active = sg_maxmin_selective_update;
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)
90 lmm_element_t elem = NULL;
92 XBT_IN("(sys=%p, var=%p)", sys, var);
95 for (i = 0; i < var->cnsts_number; i++) {
96 elem = &var->cnsts[i];
97 xbt_swag_remove(elem, &(elem->constraint->element_set));
98 xbt_swag_remove(elem, &(elem->constraint->active_element_set));
99 if (!xbt_swag_size(&(elem->constraint->element_set)))
100 make_constraint_inactive(sys, elem->constraint);
102 lmm_update_modified_set(sys, elem->constraint);
104 var->cnsts_number = 0;
108 static void lmm_var_free(lmm_system_t sys, lmm_variable_t var)
111 lmm_variable_disable(sys, var);
112 xbt_mallocator_release(sys->variable_mallocator, var);
115 static XBT_INLINE void lmm_cnst_free(lmm_system_t sys,
116 lmm_constraint_t cnst)
118 /* xbt_assert(xbt_swag_size(&(cnst->element_set)), */
119 /* "This list should be empty!"); */
120 remove_active_constraint(sys, cnst);
124 lmm_constraint_t lmm_constraint_new(lmm_system_t sys, void *id,
127 lmm_constraint_t cnst = NULL;
128 s_lmm_element_t elem;
130 cnst = xbt_new0(s_lmm_constraint_t, 1);
132 cnst->id_int = Global_const_debug_id++;
133 xbt_swag_init(&(cnst->element_set),
134 xbt_swag_offset(elem, element_set_hookup));
135 xbt_swag_init(&(cnst->active_element_set),
136 xbt_swag_offset(elem, active_element_set_hookup));
138 cnst->bound = bound_value;
141 insert_constraint(sys, cnst);
146 XBT_INLINE void lmm_constraint_shared(lmm_constraint_t cnst)
151 XBT_INLINE int lmm_constraint_is_shared(lmm_constraint_t cnst)
153 return (cnst->shared);
156 XBT_INLINE void lmm_constraint_free(lmm_system_t sys,
157 lmm_constraint_t cnst)
159 remove_constraint(sys, cnst);
160 lmm_cnst_free(sys, cnst);
163 static void *lmm_variable_mallocator_new_f(void)
165 lmm_variable_t var = xbt_new(s_lmm_variable_t, 1);
166 var->cnsts = NULL; /* will be created by realloc */
170 static void lmm_variable_mallocator_free_f(void *var)
172 xbt_free(((lmm_variable_t) var)->cnsts);
176 lmm_variable_t lmm_variable_new(lmm_system_t sys, void *id,
178 double bound, int number_of_constraints)
180 lmm_variable_t var = NULL;
183 XBT_IN("(sys=%p, id=%p, weight=%f, bound=%f, num_cons =%d)",
184 sys, id, weight, bound, number_of_constraints);
186 var = xbt_mallocator_get(sys->variable_mallocator);
188 var->id_int = Global_debug_id++;
189 var->cnsts = xbt_realloc(var->cnsts, number_of_constraints * sizeof(s_lmm_element_t));
190 for (i = 0; i < number_of_constraints; i++) {
191 var->cnsts[i].element_set_hookup.next = NULL;
192 var->cnsts[i].element_set_hookup.prev = NULL;
193 var->cnsts[i].active_element_set_hookup.next = NULL;
194 var->cnsts[i].active_element_set_hookup.prev = NULL;
195 var->cnsts[i].constraint = NULL;
196 var->cnsts[i].variable = NULL;
197 var->cnsts[i].value = 0.0;
199 var->cnsts_size = number_of_constraints;
200 var->cnsts_number = 0;
201 var->weight = weight;
207 var->func_f = func_f_def;
208 var->func_fp = func_fp_def;
209 var->func_fpi = func_fpi_def;
211 var->variable_set_hookup.next = NULL;
212 var->variable_set_hookup.prev = NULL;
213 var->saturated_variable_set_hookup.next = NULL;
214 var->saturated_variable_set_hookup.prev = NULL;
217 xbt_swag_insert_at_head(var, &(sys->variable_set));
219 xbt_swag_insert_at_tail(var, &(sys->variable_set));
224 void lmm_variable_free(lmm_system_t sys, lmm_variable_t var)
226 remove_variable(sys, var);
227 lmm_var_free(sys, var);
230 XBT_INLINE double lmm_variable_getvalue(lmm_variable_t var)
235 XBT_INLINE double lmm_variable_getbound(lmm_variable_t var)
240 void lmm_expand(lmm_system_t sys, lmm_constraint_t cnst,
241 lmm_variable_t var, double value)
243 lmm_element_t elem = NULL;
247 xbt_assert(var->cnsts_number < var->cnsts_size, "Too much constraints");
249 elem = &(var->cnsts[var->cnsts_number++]);
252 elem->constraint = cnst;
253 elem->variable = var;
256 xbt_swag_insert_at_head(elem, &(elem->constraint->element_set));
258 xbt_swag_insert_at_tail(elem, &(elem->constraint->element_set));
260 make_constraint_active(sys, cnst);
261 lmm_update_modified_set(sys, cnst);
264 void lmm_expand_add(lmm_system_t sys, lmm_constraint_t cnst,
265 lmm_variable_t var, double value)
270 for (i = 0; i < var->cnsts_number; i++)
271 if (var->cnsts[i].constraint == cnst)
274 if (i < var->cnsts_number) {
276 var->cnsts[i].value += value;
278 var->cnsts[i].value = MAX(var->cnsts[i].value, value);
279 lmm_update_modified_set(sys, cnst);
281 lmm_expand(sys, cnst, var, value);
284 void lmm_elem_set_value(lmm_system_t sys, lmm_constraint_t cnst,
285 lmm_variable_t var, double value)
289 for (i = 0; i < var->cnsts_number; i++)
290 if (var->cnsts[i].constraint == cnst)
293 if (i < var->cnsts_number) {
294 var->cnsts[i].value = value;
296 lmm_update_modified_set(sys, cnst);
301 XBT_INLINE lmm_constraint_t lmm_get_cnst_from_var(lmm_system_t sys,
305 if (num < var->cnsts_number)
306 return (var->cnsts[num].constraint);
311 XBT_INLINE int lmm_get_number_of_cnst_from_var(lmm_system_t sys,
314 return (var->cnsts_number);
317 lmm_variable_t lmm_get_var_from_cnst(lmm_system_t sys,
318 lmm_constraint_t cnst,
319 lmm_element_t * elem)
322 *elem = xbt_swag_getFirst(&(cnst->element_set));
324 *elem = xbt_swag_getNext(*elem, cnst->element_set.offset);
326 return (*elem)->variable;
331 XBT_INLINE void *lmm_constraint_id(lmm_constraint_t cnst)
336 XBT_INLINE void *lmm_variable_id(lmm_variable_t var)
341 static XBT_INLINE void saturated_constraint_set_update(lmm_system_t sys,
346 lmm_constraint_t useless_cnst = NULL;
348 XBT_IN("sys=%p, cnst=%p, min_usage=%f", sys, cnst, *min_usage);
349 if (cnst->usage <= 0) {
353 if (cnst->remaining <= 0) {
357 if ((*min_usage < 0) || (*min_usage > cnst->remaining / cnst->usage)) {
358 *min_usage = cnst->remaining / cnst->usage;
359 XBT_LOG(xbt_log_priority_trace,
360 "min_usage=%f (cnst->remaining=%f, cnst->usage=%f)", *min_usage,
361 cnst->remaining, cnst->usage);
362 while ((useless_cnst =
363 xbt_swag_getFirst(&(sys->saturated_constraint_set))))
364 xbt_swag_remove(useless_cnst, &(sys->saturated_constraint_set));
366 xbt_swag_insert(cnst, &(sys->saturated_constraint_set));
367 } else if (*min_usage == cnst->remaining / cnst->usage) {
368 xbt_swag_insert(cnst, &(sys->saturated_constraint_set));
373 static XBT_INLINE void saturated_variable_set_update(lmm_system_t sys)
375 lmm_constraint_t cnst = NULL;
376 xbt_swag_t cnst_list = NULL;
377 lmm_element_t elem = NULL;
378 xbt_swag_t elem_list = NULL;
380 cnst_list = &(sys->saturated_constraint_set);
381 while ((cnst = xbt_swag_getFirst(cnst_list))) {
382 elem_list = &(cnst->active_element_set);
383 xbt_swag_foreach(elem, elem_list) {
384 if (elem->variable->weight <= 0)
386 if ((elem->value > 0))
387 xbt_swag_insert(elem->variable, &(sys->saturated_variable_set));
389 xbt_swag_remove(cnst, cnst_list);
393 void lmm_print(lmm_system_t sys)
395 lmm_constraint_t cnst = NULL;
396 lmm_element_t elem = NULL;
397 lmm_variable_t var = NULL;
398 xbt_swag_t cnst_list = NULL;
399 xbt_swag_t var_list = NULL;
400 xbt_swag_t elem_list = NULL;
401 char print_buf[1024];
402 char *trace_buf = xbt_malloc0(sizeof(char));
405 /* Printing Objective */
406 var_list = &(sys->variable_set);
407 sprintf(print_buf, "MAX-MIN ( ");
409 xbt_realloc(trace_buf, strlen(trace_buf) + strlen(print_buf) + 1);
410 strcat(trace_buf, print_buf);
411 xbt_swag_foreach(var, var_list) {
412 sprintf(print_buf, "'%d'(%f) ", var->id_int, var->weight);
414 xbt_realloc(trace_buf, strlen(trace_buf) + strlen(print_buf) + 1);
415 strcat(trace_buf, print_buf);
417 sprintf(print_buf, ")");
419 xbt_realloc(trace_buf, strlen(trace_buf) + strlen(print_buf) + 1);
420 strcat(trace_buf, print_buf);
421 XBT_DEBUG("%20s", trace_buf);
422 trace_buf[0] = '\000';
424 XBT_DEBUG("Constraints");
425 /* Printing Constraints */
426 cnst_list = &(sys->active_constraint_set);
427 xbt_swag_foreach(cnst, cnst_list) {
429 elem_list = &(cnst->element_set);
430 sprintf(print_buf, "\t");
432 xbt_realloc(trace_buf, strlen(trace_buf) + strlen(print_buf) + 1);
433 strcat(trace_buf, print_buf);
434 sprintf(print_buf, "%s(",(cnst->shared)?"":"max");
436 xbt_realloc(trace_buf,
437 strlen(trace_buf) + strlen(print_buf) + 1);
438 strcat(trace_buf, print_buf);
439 xbt_swag_foreach(elem, elem_list) {
440 sprintf(print_buf, "%f.'%d'(%f) %s ", elem->value,
441 elem->variable->id_int, elem->variable->value,(cnst->shared)?"+":",");
443 xbt_realloc(trace_buf,
444 strlen(trace_buf) + strlen(print_buf) + 1);
445 strcat(trace_buf, print_buf);
447 sum += elem->value * elem->variable->value;
449 sum = MAX(sum,elem->value * elem->variable->value);
451 sprintf(print_buf, "0) <= %f ('%d')", cnst->bound, cnst->id_int);
453 xbt_realloc(trace_buf, strlen(trace_buf) + strlen(print_buf) + 1);
454 strcat(trace_buf, print_buf);
457 sprintf(print_buf, " [MAX-Constraint]");
459 xbt_realloc(trace_buf,
460 strlen(trace_buf) + strlen(print_buf) + 1);
461 strcat(trace_buf, print_buf);
463 XBT_DEBUG("%s", trace_buf);
464 trace_buf[0] = '\000';
465 xbt_assert(!double_positive(sum - cnst->bound),
466 "Incorrect value (%f is not smaller than %f): %g",
467 sum, cnst->bound, sum - cnst->bound);
470 XBT_DEBUG("Variables");
471 /* Printing Result */
472 xbt_swag_foreach(var, var_list) {
473 if (var->bound > 0) {
474 XBT_DEBUG("'%d'(%f) : %f (<=%f)", var->id_int, var->weight, var->value,
476 xbt_assert(!double_positive(var->value - var->bound),
477 "Incorrect value (%f is not smaller than %f",
478 var->value, var->bound);
480 XBT_DEBUG("'%d'(%f) : %f", var->id_int, var->weight, var->value);
487 void lmm_solve(lmm_system_t sys)
489 lmm_variable_t var = NULL;
490 lmm_constraint_t cnst = NULL;
491 lmm_element_t elem = NULL;
492 xbt_swag_t cnst_list = NULL;
493 xbt_swag_t var_list = NULL;
494 xbt_swag_t elem_list = NULL;
495 double min_usage = -1;
496 double min_bound = -1;
498 if (!(sys->modified))
501 XBT_IN("(sys=%p)", sys);
504 * Compute Usage and store the variables that reach the maximum.
508 selective_update_active ? &(sys->modified_constraint_set) :
509 &(sys->active_constraint_set);
511 XBT_DEBUG("Active constraints : %d", xbt_swag_size(cnst_list));
512 /* Init: Only modified code portions */
513 xbt_swag_foreach(cnst, cnst_list) {
514 elem_list = &(cnst->element_set);
515 //XBT_DEBUG("Variable set : %d", xbt_swag_size(elem_list));
516 xbt_swag_foreach(elem, elem_list) {
517 var = elem->variable;
518 if (var->weight <= 0.0)
524 xbt_swag_foreach(cnst, cnst_list) {
526 cnst->remaining = cnst->bound;
527 if (cnst->remaining == 0)
530 elem_list = &(cnst->element_set);
531 xbt_swag_foreach(elem, elem_list) {
532 /* 0-weighted elements (ie, sleep actions) are at the end of the swag and we don't want to consider them */
533 if (elem->variable->weight <= 0)
535 if ((elem->value > 0)) {
537 cnst->usage += elem->value / elem->variable->weight;
538 else if (cnst->usage < elem->value / elem->variable->weight)
539 cnst->usage = elem->value / elem->variable->weight;
541 make_elem_active(elem);
543 xbt_swag_insert((elem->variable)->id, keep_track);
547 XBT_DEBUG("Constraint Usage '%d' : %f", cnst->id_int, cnst->usage);
548 /* Saturated constraints update */
549 saturated_constraint_set_update(sys, cnst, &min_usage);
551 saturated_variable_set_update(sys);
553 /* Saturated variables update */
556 /* Fix the variables that have to be */
557 var_list = &(sys->saturated_variable_set);
559 xbt_swag_foreach(var, var_list) {
560 if (var->weight <= 0.0)
562 /* First check if some of these variables have reach their upper
563 bound and update min_usage accordingly. */
565 ("var=%d, var->bound=%f, var->weight=%f, min_usage=%f, var->bound*var->weight=%f",
566 var->id_int, var->bound, var->weight, min_usage,
567 var->bound * var->weight);
568 if ((var->bound > 0) && (var->bound * var->weight < min_usage)) {
570 min_bound = var->bound;
572 min_bound = MIN(min_bound, var->bound);
573 XBT_DEBUG("Updated min_bound=%f", min_bound);
578 while ((var = xbt_swag_getFirst(var_list))) {
582 var->value = min_usage / var->weight;
584 if (min_bound == var->bound)
585 var->value = var->bound;
587 xbt_swag_remove(var, var_list);
591 XBT_DEBUG("Min usage: %f, Var(%d)->weight: %f, Var(%d)->value: %f ",
592 min_usage, var->id_int, var->weight, var->id_int, var->value);
597 for (i = 0; i < var->cnsts_number; i++) {
598 elem = &var->cnsts[i];
599 cnst = elem->constraint;
601 double_update(&(cnst->remaining), elem->value * var->value);
602 double_update(&(cnst->usage), elem->value / var->weight);
603 make_elem_inactive(elem);
604 } else { /* FIXME one day: We recompute usage.... :( */
606 make_elem_inactive(elem);
607 elem_list = &(cnst->element_set);
608 xbt_swag_foreach(elem, elem_list) {
609 if (elem->variable->weight <= 0)
611 if (elem->variable->value > 0)
613 if ((elem->value > 0)) {
615 MAX(cnst->usage, elem->value / elem->variable->weight);
616 XBT_DEBUG("Constraint Usage %d : %f", cnst->id_int,
618 make_elem_active(elem);
623 xbt_swag_remove(var, var_list);
626 /* Find out which variables reach the maximum */
628 sys->selective_update_active ? &(sys->modified_constraint_set) :
629 &(sys->active_constraint_set);
632 xbt_swag_foreach(cnst, cnst_list) {
633 saturated_constraint_set_update(sys, cnst, &min_usage);
635 saturated_variable_set_update(sys);
637 } while (xbt_swag_size(&(sys->saturated_variable_set)));
640 if (sys->selective_update_active)
641 lmm_remove_all_modified_set(sys);
643 if (XBT_LOG_ISENABLED(surf_maxmin, xbt_log_priority_debug)) {
649 /* Not a O(1) function */
651 void lmm_update(lmm_system_t sys, lmm_constraint_t cnst,
652 lmm_variable_t var, double value)
656 for (i = 0; i < var->cnsts_number; i++)
657 if (var->cnsts[i].constraint == cnst) {
658 var->cnsts[i].value = value;
660 lmm_update_modified_set(sys, cnst);
665 /** \brief Attribute the value bound to var->bound.
667 * \param sys the lmm_system_t
668 * \param var the lmm_variable_t
669 * \param bound the new bound to associate with var
671 * Makes var->bound equal to bound. Whenever this function is called
672 * a change is signed in the system. To
673 * avoid false system changing detection it is a good idea to test
674 * (bound != 0) before calling it.
677 void lmm_update_variable_bound(lmm_system_t sys, lmm_variable_t var,
685 for (i = 0; i < var->cnsts_number; i++)
686 lmm_update_modified_set(sys, var->cnsts[i].constraint);
691 void lmm_update_variable_weight(lmm_system_t sys, lmm_variable_t var,
697 if (weight == var->weight)
699 XBT_IN("(sys=%p, var=%p, weight=%f)", sys, var, weight);
701 var->weight = weight;
702 xbt_swag_remove(var, &(sys->variable_set));
704 xbt_swag_insert_at_head(var, &(sys->variable_set));
706 xbt_swag_insert_at_tail(var, &(sys->variable_set));
708 for (i = 0; i < var->cnsts_number; i++) {
709 elem = &var->cnsts[i];
710 xbt_swag_remove(elem, &(elem->constraint->element_set));
712 xbt_swag_insert_at_head(elem, &(elem->constraint->element_set));
714 xbt_swag_insert_at_tail(elem, &(elem->constraint->element_set));
716 lmm_update_modified_set(sys, elem->constraint);
724 XBT_INLINE double lmm_get_variable_weight(lmm_variable_t var)
729 XBT_INLINE void lmm_update_constraint_bound(lmm_system_t sys,
730 lmm_constraint_t cnst,
734 lmm_update_modified_set(sys, cnst);
738 XBT_INLINE int lmm_constraint_used(lmm_system_t sys, lmm_constraint_t cnst)
740 return xbt_swag_belongs(cnst, &(sys->active_constraint_set));
743 XBT_INLINE lmm_constraint_t lmm_get_first_active_constraint(lmm_system_t
746 return xbt_swag_getFirst(&(sys->active_constraint_set));
749 XBT_INLINE lmm_constraint_t lmm_get_next_active_constraint(lmm_system_t
754 return xbt_swag_getNext(cnst, (sys->active_constraint_set).offset);
757 #ifdef HAVE_LATENCY_BOUND_TRACKING
758 XBT_INLINE int lmm_is_variable_limited_by_latency(lmm_variable_t var)
760 return (double_equals(var->bound, var->value));
765 /** \brief Update the constraint set propagating recursively to
766 * other constraints so the system should not be entirely computed.
768 * \param sys the lmm_system_t
769 * \param cnst the lmm_constraint_t affected by the change
771 * A recursive algorithm to optimize the system recalculation selecting only
772 * constraints that have changed. Each constraint change is propagated
773 * to the list of constraints for each variable.
775 static void lmm_update_modified_set(lmm_system_t sys,
776 lmm_constraint_t cnst)
778 lmm_element_t elem = NULL;
779 lmm_variable_t var = NULL;
780 xbt_swag_t elem_list = NULL;
783 /* return if selective update isn't active */
784 if (!sys->selective_update_active)
787 //XBT_DEBUG("Updating modified constraint set with constraint %d", cnst->id_int);
789 if (xbt_swag_belongs(cnst, &(sys->modified_constraint_set)))
792 //XBT_DEBUG("Inserting into modified constraint set %d", cnst->id_int);
794 /* add to modified set */
795 xbt_swag_insert(cnst, &(sys->modified_constraint_set));
797 elem_list = &(cnst->element_set);
798 xbt_swag_foreach(elem, elem_list) {
799 var = elem->variable;
800 for (i = 0; i < var->cnsts_number; i++)
801 if (cnst != var->cnsts[i].constraint) {
802 //XBT_DEBUG("Updating modified %d calling for %d", cnst->id_int, var->cnsts[i].constraint->id_int);
803 lmm_update_modified_set(sys, var->cnsts[i].constraint);
808 /** \brief Remove all constraints of the modified_constraint_set.
810 * \param sys the lmm_system_t
812 static void lmm_remove_all_modified_set(lmm_system_t sys)
814 xbt_swag_t modified_constraint_set = &sys->modified_constraint_set;
815 lmm_constraint_t cnst;
816 lmm_constraint_t cnst_next;
818 xbt_swag_foreach_safe(cnst, cnst_next, modified_constraint_set) {
819 xbt_swag_remove(cnst, modified_constraint_set);