1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /* Copyright (c) 2018 Mellanox Technologies. All rights reserved */
4 #include <linux/module.h>
5 #include <linux/slab.h>
6 #include <linux/rhashtable.h>
8 #include <linux/list.h>
9 #include <linux/sort.h>
10 #include <linux/objagg.h>
12 #define CREATE_TRACE_POINTS
13 #include <trace/events/objagg.h>
16 struct rhashtable node_ht;
17 struct rhashtable_params ht_params;
18 struct list_head node_list;
19 unsigned int node_count;
20 unsigned int root_count;
21 unsigned int refcount;
22 const struct objagg_ops *ops;
25 struct objagg_hints_node {
26 struct rhash_head ht_node; /* member of objagg_hints->node_ht */
27 struct list_head list; /* member of objagg_hints->node_list */
28 struct objagg_hints_node *parent;
30 struct objagg_obj_stats_info stats_info;
34 static struct objagg_hints_node *
35 objagg_hints_lookup(struct objagg_hints *objagg_hints, void *obj)
39 return rhashtable_lookup_fast(&objagg_hints->node_ht, obj,
40 objagg_hints->ht_params);
44 const struct objagg_ops *ops;
46 struct rhashtable obj_ht;
47 struct rhashtable_params ht_params;
48 struct list_head obj_list;
49 unsigned int obj_count;
51 struct objagg_hints *hints;
55 struct rhash_head ht_node; /* member of objagg->obj_ht */
56 struct list_head list; /* member of objagg->obj_list */
57 struct objagg_obj *parent; /* if the object is nested, this
58 * holds pointer to parent, otherwise NULL
61 void *delta_priv; /* user delta private */
62 void *root_priv; /* user root private */
65 unsigned int refcount; /* counts number of users of this object
66 * including nested objects
68 struct objagg_obj_stats stats;
72 static unsigned int objagg_obj_ref_inc(struct objagg_obj *objagg_obj)
74 return ++objagg_obj->refcount;
77 static unsigned int objagg_obj_ref_dec(struct objagg_obj *objagg_obj)
79 return --objagg_obj->refcount;
82 static void objagg_obj_stats_inc(struct objagg_obj *objagg_obj)
84 objagg_obj->stats.user_count++;
85 objagg_obj->stats.delta_user_count++;
86 if (objagg_obj->parent)
87 objagg_obj->parent->stats.delta_user_count++;
90 static void objagg_obj_stats_dec(struct objagg_obj *objagg_obj)
92 objagg_obj->stats.user_count--;
93 objagg_obj->stats.delta_user_count--;
94 if (objagg_obj->parent)
95 objagg_obj->parent->stats.delta_user_count--;
98 static bool objagg_obj_is_root(const struct objagg_obj *objagg_obj)
100 /* Nesting is not supported, so we can use ->parent
101 * to figure out if the object is root.
103 return !objagg_obj->parent;
107 * objagg_obj_root_priv - obtains root private for an object
108 * @objagg_obj: objagg object instance
110 * Note: all locking must be provided by the caller.
112 * Either the object is root itself when the private is returned
113 * directly, or the parent is root and its private is returned
116 * Returns a user private root pointer.
118 const void *objagg_obj_root_priv(const struct objagg_obj *objagg_obj)
120 if (objagg_obj_is_root(objagg_obj))
121 return objagg_obj->root_priv;
122 WARN_ON(!objagg_obj_is_root(objagg_obj->parent));
123 return objagg_obj->parent->root_priv;
125 EXPORT_SYMBOL(objagg_obj_root_priv);
128 * objagg_obj_delta_priv - obtains delta private for an object
129 * @objagg_obj: objagg object instance
131 * Note: all locking must be provided by the caller.
133 * Returns user private delta pointer or NULL in case the passed
136 const void *objagg_obj_delta_priv(const struct objagg_obj *objagg_obj)
138 if (objagg_obj_is_root(objagg_obj))
140 return objagg_obj->delta_priv;
142 EXPORT_SYMBOL(objagg_obj_delta_priv);
145 * objagg_obj_raw - obtains object user private pointer
146 * @objagg_obj: objagg object instance
148 * Note: all locking must be provided by the caller.
150 * Returns user private pointer as was passed to objagg_obj_get() by "obj" arg.
152 const void *objagg_obj_raw(const struct objagg_obj *objagg_obj)
154 return objagg_obj->obj;
156 EXPORT_SYMBOL(objagg_obj_raw);
158 static struct objagg_obj *objagg_obj_lookup(struct objagg *objagg, void *obj)
160 return rhashtable_lookup_fast(&objagg->obj_ht, obj, objagg->ht_params);
163 static int objagg_obj_parent_assign(struct objagg *objagg,
164 struct objagg_obj *objagg_obj,
165 struct objagg_obj *parent,
166 bool take_parent_ref)
170 delta_priv = objagg->ops->delta_create(objagg->priv, parent->obj,
172 if (IS_ERR(delta_priv))
173 return PTR_ERR(delta_priv);
175 /* User returned a delta private, that means that
176 * our object can be aggregated into the parent.
178 objagg_obj->parent = parent;
179 objagg_obj->delta_priv = delta_priv;
181 objagg_obj_ref_inc(objagg_obj->parent);
182 trace_objagg_obj_parent_assign(objagg, objagg_obj,
188 static int objagg_obj_parent_lookup_assign(struct objagg *objagg,
189 struct objagg_obj *objagg_obj)
191 struct objagg_obj *objagg_obj_cur;
194 list_for_each_entry(objagg_obj_cur, &objagg->obj_list, list) {
195 /* Nesting is not supported. In case the object
196 * is not root, it cannot be assigned as parent.
198 if (!objagg_obj_is_root(objagg_obj_cur))
200 err = objagg_obj_parent_assign(objagg, objagg_obj,
201 objagg_obj_cur, true);
208 static void __objagg_obj_put(struct objagg *objagg,
209 struct objagg_obj *objagg_obj);
211 static void objagg_obj_parent_unassign(struct objagg *objagg,
212 struct objagg_obj *objagg_obj)
214 trace_objagg_obj_parent_unassign(objagg, objagg_obj,
216 objagg_obj->parent->refcount);
217 objagg->ops->delta_destroy(objagg->priv, objagg_obj->delta_priv);
218 __objagg_obj_put(objagg, objagg_obj->parent);
221 static int objagg_obj_root_id_alloc(struct objagg *objagg,
222 struct objagg_obj *objagg_obj,
223 struct objagg_hints_node *hnode)
225 unsigned int min, max;
228 /* In case there are no hints available, the root id is invalid. */
229 if (!objagg->hints) {
230 objagg_obj->root_id = OBJAGG_OBJ_ROOT_ID_INVALID;
235 min = hnode->root_id;
236 max = hnode->root_id;
238 /* For objects with no hint, start after the last
241 min = objagg->hints->root_count;
245 root_id = ida_alloc_range(&objagg->root_ida, min, max, GFP_KERNEL);
249 objagg_obj->root_id = root_id;
253 static void objagg_obj_root_id_free(struct objagg *objagg,
254 struct objagg_obj *objagg_obj)
258 ida_free(&objagg->root_ida, objagg_obj->root_id);
261 static int objagg_obj_root_create(struct objagg *objagg,
262 struct objagg_obj *objagg_obj,
263 struct objagg_hints_node *hnode)
267 err = objagg_obj_root_id_alloc(objagg, objagg_obj, hnode);
270 objagg_obj->root_priv = objagg->ops->root_create(objagg->priv,
272 objagg_obj->root_id);
273 if (IS_ERR(objagg_obj->root_priv)) {
274 err = PTR_ERR(objagg_obj->root_priv);
275 goto err_root_create;
277 trace_objagg_obj_root_create(objagg, objagg_obj);
281 objagg_obj_root_id_free(objagg, objagg_obj);
285 static void objagg_obj_root_destroy(struct objagg *objagg,
286 struct objagg_obj *objagg_obj)
288 trace_objagg_obj_root_destroy(objagg, objagg_obj);
289 objagg->ops->root_destroy(objagg->priv, objagg_obj->root_priv);
290 objagg_obj_root_id_free(objagg, objagg_obj);
293 static struct objagg_obj *__objagg_obj_get(struct objagg *objagg, void *obj);
295 static int objagg_obj_init_with_hints(struct objagg *objagg,
296 struct objagg_obj *objagg_obj,
299 struct objagg_hints_node *hnode;
300 struct objagg_obj *parent;
303 hnode = objagg_hints_lookup(objagg->hints, objagg_obj->obj);
311 return objagg_obj_root_create(objagg, objagg_obj, hnode);
313 parent = __objagg_obj_get(objagg, hnode->parent->obj);
315 return PTR_ERR(parent);
317 err = objagg_obj_parent_assign(objagg, objagg_obj, parent, false);
321 goto err_parent_assign;
327 objagg_obj_put(objagg, parent);
331 static int objagg_obj_init(struct objagg *objagg,
332 struct objagg_obj *objagg_obj)
337 /* First, try to use hints if they are available and
338 * if they provide result.
340 err = objagg_obj_init_with_hints(objagg, objagg_obj, &hint_found);
347 /* Try to find if the object can be aggregated under an existing one. */
348 err = objagg_obj_parent_lookup_assign(objagg, objagg_obj);
351 /* If aggregation is not possible, make the object a root. */
352 return objagg_obj_root_create(objagg, objagg_obj, NULL);
355 static void objagg_obj_fini(struct objagg *objagg,
356 struct objagg_obj *objagg_obj)
358 if (!objagg_obj_is_root(objagg_obj))
359 objagg_obj_parent_unassign(objagg, objagg_obj);
361 objagg_obj_root_destroy(objagg, objagg_obj);
364 static struct objagg_obj *objagg_obj_create(struct objagg *objagg, void *obj)
366 struct objagg_obj *objagg_obj;
369 objagg_obj = kzalloc(sizeof(*objagg_obj) + objagg->ops->obj_size,
372 return ERR_PTR(-ENOMEM);
373 objagg_obj_ref_inc(objagg_obj);
374 memcpy(objagg_obj->obj, obj, objagg->ops->obj_size);
376 err = objagg_obj_init(objagg, objagg_obj);
380 err = rhashtable_insert_fast(&objagg->obj_ht, &objagg_obj->ht_node,
384 list_add(&objagg_obj->list, &objagg->obj_list);
386 trace_objagg_obj_create(objagg, objagg_obj);
391 objagg_obj_fini(objagg, objagg_obj);
397 static struct objagg_obj *__objagg_obj_get(struct objagg *objagg, void *obj)
399 struct objagg_obj *objagg_obj;
401 /* First, try to find the object exactly as user passed it,
402 * perhaps it is already in use.
404 objagg_obj = objagg_obj_lookup(objagg, obj);
406 objagg_obj_ref_inc(objagg_obj);
410 return objagg_obj_create(objagg, obj);
414 * objagg_obj_get - gets an object within objagg instance
415 * @objagg: objagg instance
416 * @obj: user-specific private object pointer
418 * Note: all locking must be provided by the caller.
420 * Size of the "obj" memory is specified in "objagg->ops".
422 * There are 3 main options this function wraps:
423 * 1) The object according to "obj" already exist. In that case
424 * the reference counter is incrementes and the object is returned.
425 * 2) The object does not exist, but it can be aggregated within
426 * another object. In that case, user ops->delta_create() is called
427 * to obtain delta data and a new object is created with returned
428 * user-delta private pointer.
429 * 3) The object does not exist and cannot be aggregated into
430 * any of the existing objects. In that case, user ops->root_create()
431 * is called to create the root and a new object is created with
432 * returned user-root private pointer.
434 * Returns a pointer to objagg object instance in case of success,
435 * otherwise it returns pointer error using ERR_PTR macro.
437 struct objagg_obj *objagg_obj_get(struct objagg *objagg, void *obj)
439 struct objagg_obj *objagg_obj;
441 objagg_obj = __objagg_obj_get(objagg, obj);
442 if (IS_ERR(objagg_obj))
444 objagg_obj_stats_inc(objagg_obj);
445 trace_objagg_obj_get(objagg, objagg_obj, objagg_obj->refcount);
448 EXPORT_SYMBOL(objagg_obj_get);
450 static void objagg_obj_destroy(struct objagg *objagg,
451 struct objagg_obj *objagg_obj)
453 trace_objagg_obj_destroy(objagg, objagg_obj);
455 list_del(&objagg_obj->list);
456 rhashtable_remove_fast(&objagg->obj_ht, &objagg_obj->ht_node,
458 objagg_obj_fini(objagg, objagg_obj);
462 static void __objagg_obj_put(struct objagg *objagg,
463 struct objagg_obj *objagg_obj)
465 if (!objagg_obj_ref_dec(objagg_obj))
466 objagg_obj_destroy(objagg, objagg_obj);
470 * objagg_obj_put - puts an object within objagg instance
471 * @objagg: objagg instance
472 * @objagg_obj: objagg object instance
474 * Note: all locking must be provided by the caller.
476 * Symmetric to objagg_obj_get().
478 void objagg_obj_put(struct objagg *objagg, struct objagg_obj *objagg_obj)
480 trace_objagg_obj_put(objagg, objagg_obj, objagg_obj->refcount);
481 objagg_obj_stats_dec(objagg_obj);
482 __objagg_obj_put(objagg, objagg_obj);
484 EXPORT_SYMBOL(objagg_obj_put);
487 * objagg_create - creates a new objagg instance
488 * @ops: user-specific callbacks
489 * @objagg_hints: hints, can be NULL
490 * @priv: pointer to a private data passed to the ops
492 * Note: all locking must be provided by the caller.
494 * The purpose of the library is to provide an infrastructure to
495 * aggregate user-specified objects. Library does not care about the type
496 * of the object. User fills-up ops which take care of the specific
497 * user object manipulation.
499 * As a very stupid example, consider integer numbers. For example
500 * number 8 as a root object. That can aggregate number 9 with delta 1,
501 * number 10 with delta 2, etc. This example is implemented as
502 * a part of a testing module in test_objagg.c file.
504 * Each objagg instance contains multiple trees. Each tree node is
505 * represented by "an object". In the current implementation there can be
506 * only roots and leafs nodes. Leaf nodes are called deltas.
507 * But in general, this can be easily extended for intermediate nodes.
508 * In that extension, a delta would be associated with all non-root
511 * Returns a pointer to newly created objagg instance in case of success,
512 * otherwise it returns pointer error using ERR_PTR macro.
514 struct objagg *objagg_create(const struct objagg_ops *ops,
515 struct objagg_hints *objagg_hints, void *priv)
517 struct objagg *objagg;
520 if (WARN_ON(!ops || !ops->root_create || !ops->root_destroy ||
521 !ops->delta_check || !ops->delta_create ||
522 !ops->delta_destroy))
523 return ERR_PTR(-EINVAL);
525 objagg = kzalloc(sizeof(*objagg), GFP_KERNEL);
527 return ERR_PTR(-ENOMEM);
530 objagg->hints = objagg_hints;
531 objagg_hints->refcount++;
534 INIT_LIST_HEAD(&objagg->obj_list);
536 objagg->ht_params.key_len = ops->obj_size;
537 objagg->ht_params.key_offset = offsetof(struct objagg_obj, obj);
538 objagg->ht_params.head_offset = offsetof(struct objagg_obj, ht_node);
540 err = rhashtable_init(&objagg->obj_ht, &objagg->ht_params);
542 goto err_rhashtable_init;
544 ida_init(&objagg->root_ida);
546 trace_objagg_create(objagg);
553 EXPORT_SYMBOL(objagg_create);
556 * objagg_destroy - destroys a new objagg instance
557 * @objagg: objagg instance
559 * Note: all locking must be provided by the caller.
561 void objagg_destroy(struct objagg *objagg)
563 trace_objagg_destroy(objagg);
564 ida_destroy(&objagg->root_ida);
565 WARN_ON(!list_empty(&objagg->obj_list));
566 rhashtable_destroy(&objagg->obj_ht);
568 objagg_hints_put(objagg->hints);
571 EXPORT_SYMBOL(objagg_destroy);
573 static int objagg_stats_info_sort_cmp_func(const void *a, const void *b)
575 const struct objagg_obj_stats_info *stats_info1 = a;
576 const struct objagg_obj_stats_info *stats_info2 = b;
578 if (stats_info1->is_root != stats_info2->is_root)
579 return stats_info2->is_root - stats_info1->is_root;
580 if (stats_info1->stats.delta_user_count !=
581 stats_info2->stats.delta_user_count)
582 return stats_info2->stats.delta_user_count -
583 stats_info1->stats.delta_user_count;
584 return stats_info2->stats.user_count - stats_info1->stats.user_count;
588 * objagg_stats_get - obtains stats of the objagg instance
589 * @objagg: objagg instance
591 * Note: all locking must be provided by the caller.
593 * The returned structure contains statistics of all object
594 * currently in use, ordered by following rules:
595 * 1) Root objects are always on lower indexes than the rest.
596 * 2) Objects with higher delta user count are always on lower
598 * 3) In case more objects have the same delta user count,
599 * the objects are ordered by user count.
601 * Returns a pointer to stats instance in case of success,
602 * otherwise it returns pointer error using ERR_PTR macro.
604 const struct objagg_stats *objagg_stats_get(struct objagg *objagg)
606 struct objagg_stats *objagg_stats;
607 struct objagg_obj *objagg_obj;
610 objagg_stats = kzalloc(struct_size(objagg_stats, stats_info,
611 objagg->obj_count), GFP_KERNEL);
613 return ERR_PTR(-ENOMEM);
616 list_for_each_entry(objagg_obj, &objagg->obj_list, list) {
617 memcpy(&objagg_stats->stats_info[i].stats, &objagg_obj->stats,
618 sizeof(objagg_stats->stats_info[0].stats));
619 objagg_stats->stats_info[i].objagg_obj = objagg_obj;
620 objagg_stats->stats_info[i].is_root =
621 objagg_obj_is_root(objagg_obj);
622 if (objagg_stats->stats_info[i].is_root)
623 objagg_stats->root_count++;
626 objagg_stats->stats_info_count = i;
628 sort(objagg_stats->stats_info, objagg_stats->stats_info_count,
629 sizeof(struct objagg_obj_stats_info),
630 objagg_stats_info_sort_cmp_func, NULL);
634 EXPORT_SYMBOL(objagg_stats_get);
637 * objagg_stats_put - puts stats of the objagg instance
638 * @objagg_stats: objagg instance stats
640 * Note: all locking must be provided by the caller.
642 void objagg_stats_put(const struct objagg_stats *objagg_stats)
646 EXPORT_SYMBOL(objagg_stats_put);
648 static struct objagg_hints_node *
649 objagg_hints_node_create(struct objagg_hints *objagg_hints,
650 struct objagg_obj *objagg_obj, size_t obj_size,
651 struct objagg_hints_node *parent_hnode)
653 unsigned int user_count = objagg_obj->stats.user_count;
654 struct objagg_hints_node *hnode;
657 hnode = kzalloc(sizeof(*hnode) + obj_size, GFP_KERNEL);
659 return ERR_PTR(-ENOMEM);
660 memcpy(hnode->obj, &objagg_obj->obj, obj_size);
661 hnode->stats_info.stats.user_count = user_count;
662 hnode->stats_info.stats.delta_user_count = user_count;
664 parent_hnode->stats_info.stats.delta_user_count += user_count;
666 hnode->root_id = objagg_hints->root_count++;
667 hnode->stats_info.is_root = true;
669 hnode->stats_info.objagg_obj = objagg_obj;
671 err = rhashtable_insert_fast(&objagg_hints->node_ht, &hnode->ht_node,
672 objagg_hints->ht_params);
676 list_add(&hnode->list, &objagg_hints->node_list);
677 hnode->parent = parent_hnode;
678 objagg_hints->node_count++;
687 static void objagg_hints_flush(struct objagg_hints *objagg_hints)
689 struct objagg_hints_node *hnode, *tmp;
691 list_for_each_entry_safe(hnode, tmp, &objagg_hints->node_list, list) {
692 list_del(&hnode->list);
693 rhashtable_remove_fast(&objagg_hints->node_ht, &hnode->ht_node,
694 objagg_hints->ht_params);
699 struct objagg_tmp_node {
700 struct objagg_obj *objagg_obj;
704 struct objagg_tmp_graph {
705 struct objagg_tmp_node *nodes;
706 unsigned long nodes_count;
707 unsigned long *edges;
710 static int objagg_tmp_graph_edge_index(struct objagg_tmp_graph *graph,
711 int parent_index, int index)
713 return index * graph->nodes_count + parent_index;
716 static void objagg_tmp_graph_edge_set(struct objagg_tmp_graph *graph,
717 int parent_index, int index)
719 int edge_index = objagg_tmp_graph_edge_index(graph, index,
722 __set_bit(edge_index, graph->edges);
725 static bool objagg_tmp_graph_is_edge(struct objagg_tmp_graph *graph,
726 int parent_index, int index)
728 int edge_index = objagg_tmp_graph_edge_index(graph, index,
731 return test_bit(edge_index, graph->edges);
734 static unsigned int objagg_tmp_graph_node_weight(struct objagg_tmp_graph *graph,
737 struct objagg_tmp_node *node = &graph->nodes[index];
738 unsigned int weight = node->objagg_obj->stats.user_count;
741 /* Node weight is sum of node users and all other nodes users
742 * that this node can represent with delta.
745 for (j = 0; j < graph->nodes_count; j++) {
746 if (!objagg_tmp_graph_is_edge(graph, index, j))
748 node = &graph->nodes[j];
749 if (node->crossed_out)
751 weight += node->objagg_obj->stats.user_count;
756 static int objagg_tmp_graph_node_max_weight(struct objagg_tmp_graph *graph)
758 struct objagg_tmp_node *node;
759 unsigned int max_weight = 0;
764 for (i = 0; i < graph->nodes_count; i++) {
765 node = &graph->nodes[i];
766 if (node->crossed_out)
768 weight = objagg_tmp_graph_node_weight(graph, i);
769 if (weight >= max_weight) {
777 static struct objagg_tmp_graph *objagg_tmp_graph_create(struct objagg *objagg)
779 unsigned int nodes_count = objagg->obj_count;
780 struct objagg_tmp_graph *graph;
781 struct objagg_tmp_node *node;
782 struct objagg_tmp_node *pnode;
783 struct objagg_obj *objagg_obj;
786 graph = kzalloc(sizeof(*graph), GFP_KERNEL);
790 graph->nodes = kcalloc(nodes_count, sizeof(*graph->nodes), GFP_KERNEL);
792 goto err_nodes_alloc;
793 graph->nodes_count = nodes_count;
795 graph->edges = bitmap_zalloc(nodes_count * nodes_count, GFP_KERNEL);
797 goto err_edges_alloc;
800 list_for_each_entry(objagg_obj, &objagg->obj_list, list) {
801 node = &graph->nodes[i++];
802 node->objagg_obj = objagg_obj;
805 /* Assemble a temporary graph. Insert edge X->Y in case Y can be
808 for (i = 0; i < nodes_count; i++) {
809 for (j = 0; j < nodes_count; j++) {
812 pnode = &graph->nodes[i];
813 node = &graph->nodes[j];
814 if (objagg->ops->delta_check(objagg->priv,
815 pnode->objagg_obj->obj,
816 node->objagg_obj->obj)) {
817 objagg_tmp_graph_edge_set(graph, i, j);
831 static void objagg_tmp_graph_destroy(struct objagg_tmp_graph *graph)
833 bitmap_free(graph->edges);
839 objagg_opt_simple_greedy_fillup_hints(struct objagg_hints *objagg_hints,
840 struct objagg *objagg)
842 struct objagg_hints_node *hnode, *parent_hnode;
843 struct objagg_tmp_graph *graph;
844 struct objagg_tmp_node *node;
849 graph = objagg_tmp_graph_create(objagg);
853 /* Find the nodes from the ones that can accommodate most users
854 * and cross them out of the graph. Save them to the hint list.
856 while ((index = objagg_tmp_graph_node_max_weight(graph)) != -1) {
857 node = &graph->nodes[index];
858 node->crossed_out = true;
859 hnode = objagg_hints_node_create(objagg_hints,
861 objagg->ops->obj_size,
864 err = PTR_ERR(hnode);
867 parent_hnode = hnode;
868 for (j = 0; j < graph->nodes_count; j++) {
869 if (!objagg_tmp_graph_is_edge(graph, index, j))
871 node = &graph->nodes[j];
872 if (node->crossed_out)
874 node->crossed_out = true;
875 hnode = objagg_hints_node_create(objagg_hints,
877 objagg->ops->obj_size,
880 err = PTR_ERR(hnode);
888 objagg_tmp_graph_destroy(graph);
892 struct objagg_opt_algo {
893 int (*fillup_hints)(struct objagg_hints *objagg_hints,
894 struct objagg *objagg);
897 static const struct objagg_opt_algo objagg_opt_simple_greedy = {
898 .fillup_hints = objagg_opt_simple_greedy_fillup_hints,
902 static const struct objagg_opt_algo *objagg_opt_algos[] = {
903 [OBJAGG_OPT_ALGO_SIMPLE_GREEDY] = &objagg_opt_simple_greedy,
906 static int objagg_hints_obj_cmp(struct rhashtable_compare_arg *arg,
909 struct rhashtable *ht = arg->ht;
910 struct objagg_hints *objagg_hints =
911 container_of(ht, struct objagg_hints, node_ht);
912 const struct objagg_ops *ops = objagg_hints->ops;
913 const char *ptr = obj;
915 ptr += ht->p.key_offset;
916 return ops->hints_obj_cmp ? ops->hints_obj_cmp(ptr, arg->key) :
917 memcmp(ptr, arg->key, ht->p.key_len);
921 * objagg_hints_get - obtains hints instance
922 * @objagg: objagg instance
923 * @opt_algo_type: type of hints finding algorithm
925 * Note: all locking must be provided by the caller.
927 * According to the algo type, the existing objects of objagg instance
928 * are going to be went-through to assemble an optimal tree. We call this
929 * tree hints. These hints can be later on used for creation of
930 * a new objagg instance. There, the future object creations are going
931 * to be consulted with these hints in order to find out, where exactly
932 * the new object should be put as a root or delta.
934 * Returns a pointer to hints instance in case of success,
935 * otherwise it returns pointer error using ERR_PTR macro.
937 struct objagg_hints *objagg_hints_get(struct objagg *objagg,
938 enum objagg_opt_algo_type opt_algo_type)
940 const struct objagg_opt_algo *algo = objagg_opt_algos[opt_algo_type];
941 struct objagg_hints *objagg_hints;
944 objagg_hints = kzalloc(sizeof(*objagg_hints), GFP_KERNEL);
946 return ERR_PTR(-ENOMEM);
948 objagg_hints->ops = objagg->ops;
949 objagg_hints->refcount = 1;
951 INIT_LIST_HEAD(&objagg_hints->node_list);
953 objagg_hints->ht_params.key_len = objagg->ops->obj_size;
954 objagg_hints->ht_params.key_offset =
955 offsetof(struct objagg_hints_node, obj);
956 objagg_hints->ht_params.head_offset =
957 offsetof(struct objagg_hints_node, ht_node);
958 objagg_hints->ht_params.obj_cmpfn = objagg_hints_obj_cmp;
960 err = rhashtable_init(&objagg_hints->node_ht, &objagg_hints->ht_params);
962 goto err_rhashtable_init;
964 err = algo->fillup_hints(objagg_hints, objagg);
966 goto err_fillup_hints;
968 if (WARN_ON(objagg_hints->node_count != objagg->obj_count)) {
970 goto err_node_count_check;
975 err_node_count_check:
977 objagg_hints_flush(objagg_hints);
978 rhashtable_destroy(&objagg_hints->node_ht);
983 EXPORT_SYMBOL(objagg_hints_get);
986 * objagg_hints_put - puts hints instance
987 * @objagg_hints: objagg hints instance
989 * Note: all locking must be provided by the caller.
991 void objagg_hints_put(struct objagg_hints *objagg_hints)
993 if (--objagg_hints->refcount)
995 objagg_hints_flush(objagg_hints);
996 rhashtable_destroy(&objagg_hints->node_ht);
999 EXPORT_SYMBOL(objagg_hints_put);
1002 * objagg_hints_stats_get - obtains stats of the hints instance
1003 * @objagg_hints: hints instance
1005 * Note: all locking must be provided by the caller.
1007 * The returned structure contains statistics of all objects
1008 * currently in use, ordered by following rules:
1009 * 1) Root objects are always on lower indexes than the rest.
1010 * 2) Objects with higher delta user count are always on lower
1012 * 3) In case multiple objects have the same delta user count,
1013 * the objects are ordered by user count.
1015 * Returns a pointer to stats instance in case of success,
1016 * otherwise it returns pointer error using ERR_PTR macro.
1018 const struct objagg_stats *
1019 objagg_hints_stats_get(struct objagg_hints *objagg_hints)
1021 struct objagg_stats *objagg_stats;
1022 struct objagg_hints_node *hnode;
1025 objagg_stats = kzalloc(struct_size(objagg_stats, stats_info,
1026 objagg_hints->node_count),
1029 return ERR_PTR(-ENOMEM);
1032 list_for_each_entry(hnode, &objagg_hints->node_list, list) {
1033 memcpy(&objagg_stats->stats_info[i], &hnode->stats_info,
1034 sizeof(objagg_stats->stats_info[0]));
1035 if (objagg_stats->stats_info[i].is_root)
1036 objagg_stats->root_count++;
1039 objagg_stats->stats_info_count = i;
1041 sort(objagg_stats->stats_info, objagg_stats->stats_info_count,
1042 sizeof(struct objagg_obj_stats_info),
1043 objagg_stats_info_sort_cmp_func, NULL);
1045 return objagg_stats;
1047 EXPORT_SYMBOL(objagg_hints_stats_get);
1049 MODULE_LICENSE("Dual BSD/GPL");
1050 MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
1051 MODULE_DESCRIPTION("Object aggregation manager");