1040 lines · c
1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.02/* Copyright (c) 2018 Mellanox Technologies. All rights reserved */3 4#include <linux/module.h>5#include <linux/slab.h>6#include <linux/rhashtable.h>7#include <linux/idr.h>8#include <linux/list.h>9#include <linux/sort.h>10#include <linux/objagg.h>11 12#define CREATE_TRACE_POINTS13#include <trace/events/objagg.h>14 15struct objagg_hints {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;23};24 25struct 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;29 unsigned int root_id;30 struct objagg_obj_stats_info stats_info;31 unsigned long obj[];32};33 34static struct objagg_hints_node *35objagg_hints_lookup(struct objagg_hints *objagg_hints, void *obj)36{37 if (!objagg_hints)38 return NULL;39 return rhashtable_lookup_fast(&objagg_hints->node_ht, obj,40 objagg_hints->ht_params);41}42 43struct objagg {44 const struct objagg_ops *ops;45 void *priv;46 struct rhashtable obj_ht;47 struct rhashtable_params ht_params;48 struct list_head obj_list;49 unsigned int obj_count;50 struct ida root_ida;51 struct objagg_hints *hints;52};53 54struct objagg_obj {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, this58 * holds pointer to parent, otherwise NULL59 */60 union {61 void *delta_priv; /* user delta private */62 void *root_priv; /* user root private */63 };64 unsigned int root_id;65 unsigned int refcount; /* counts number of users of this object66 * including nested objects67 */68 struct objagg_obj_stats stats;69 unsigned long obj[];70};71 72static unsigned int objagg_obj_ref_inc(struct objagg_obj *objagg_obj)73{74 return ++objagg_obj->refcount;75}76 77static unsigned int objagg_obj_ref_dec(struct objagg_obj *objagg_obj)78{79 return --objagg_obj->refcount;80}81 82static void objagg_obj_stats_inc(struct objagg_obj *objagg_obj)83{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++;88}89 90static void objagg_obj_stats_dec(struct objagg_obj *objagg_obj)91{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--;96}97 98static bool objagg_obj_is_root(const struct objagg_obj *objagg_obj)99{100 /* Nesting is not supported, so we can use ->parent101 * to figure out if the object is root.102 */103 return !objagg_obj->parent;104}105 106/**107 * objagg_obj_root_priv - obtains root private for an object108 * @objagg_obj: objagg object instance109 *110 * Note: all locking must be provided by the caller.111 *112 * Either the object is root itself when the private is returned113 * directly, or the parent is root and its private is returned114 * instead.115 *116 * Returns a user private root pointer.117 */118const void *objagg_obj_root_priv(const struct objagg_obj *objagg_obj)119{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;124}125EXPORT_SYMBOL(objagg_obj_root_priv);126 127/**128 * objagg_obj_delta_priv - obtains delta private for an object129 * @objagg_obj: objagg object instance130 *131 * Note: all locking must be provided by the caller.132 *133 * Returns user private delta pointer or NULL in case the passed134 * object is root.135 */136const void *objagg_obj_delta_priv(const struct objagg_obj *objagg_obj)137{138 if (objagg_obj_is_root(objagg_obj))139 return NULL;140 return objagg_obj->delta_priv;141}142EXPORT_SYMBOL(objagg_obj_delta_priv);143 144/**145 * objagg_obj_raw - obtains object user private pointer146 * @objagg_obj: objagg object instance147 *148 * Note: all locking must be provided by the caller.149 *150 * Returns user private pointer as was passed to objagg_obj_get() by "obj" arg.151 */152const void *objagg_obj_raw(const struct objagg_obj *objagg_obj)153{154 return objagg_obj->obj;155}156EXPORT_SYMBOL(objagg_obj_raw);157 158static struct objagg_obj *objagg_obj_lookup(struct objagg *objagg, void *obj)159{160 return rhashtable_lookup_fast(&objagg->obj_ht, obj, objagg->ht_params);161}162 163static int objagg_obj_parent_assign(struct objagg *objagg,164 struct objagg_obj *objagg_obj,165 struct objagg_obj *parent,166 bool take_parent_ref)167{168 void *delta_priv;169 170 if (WARN_ON(!objagg_obj_is_root(parent)))171 return -EINVAL;172 173 delta_priv = objagg->ops->delta_create(objagg->priv, parent->obj,174 objagg_obj->obj);175 if (IS_ERR(delta_priv))176 return PTR_ERR(delta_priv);177 178 /* User returned a delta private, that means that179 * our object can be aggregated into the parent.180 */181 objagg_obj->parent = parent;182 objagg_obj->delta_priv = delta_priv;183 if (take_parent_ref)184 objagg_obj_ref_inc(objagg_obj->parent);185 trace_objagg_obj_parent_assign(objagg, objagg_obj,186 parent,187 parent->refcount);188 return 0;189}190 191static int objagg_obj_parent_lookup_assign(struct objagg *objagg,192 struct objagg_obj *objagg_obj)193{194 struct objagg_obj *objagg_obj_cur;195 int err;196 197 list_for_each_entry(objagg_obj_cur, &objagg->obj_list, list) {198 /* Nesting is not supported. In case the object199 * is not root, it cannot be assigned as parent.200 */201 if (!objagg_obj_is_root(objagg_obj_cur))202 continue;203 err = objagg_obj_parent_assign(objagg, objagg_obj,204 objagg_obj_cur, true);205 if (!err)206 return 0;207 }208 return -ENOENT;209}210 211static void __objagg_obj_put(struct objagg *objagg,212 struct objagg_obj *objagg_obj);213 214static void objagg_obj_parent_unassign(struct objagg *objagg,215 struct objagg_obj *objagg_obj)216{217 trace_objagg_obj_parent_unassign(objagg, objagg_obj,218 objagg_obj->parent,219 objagg_obj->parent->refcount);220 objagg->ops->delta_destroy(objagg->priv, objagg_obj->delta_priv);221 __objagg_obj_put(objagg, objagg_obj->parent);222}223 224static int objagg_obj_root_id_alloc(struct objagg *objagg,225 struct objagg_obj *objagg_obj,226 struct objagg_hints_node *hnode)227{228 unsigned int min, max;229 int root_id;230 231 /* In case there are no hints available, the root id is invalid. */232 if (!objagg->hints) {233 objagg_obj->root_id = OBJAGG_OBJ_ROOT_ID_INVALID;234 return 0;235 }236 237 if (hnode) {238 min = hnode->root_id;239 max = hnode->root_id;240 } else {241 /* For objects with no hint, start after the last242 * hinted root_id.243 */244 min = objagg->hints->root_count;245 max = ~0;246 }247 248 root_id = ida_alloc_range(&objagg->root_ida, min, max, GFP_KERNEL);249 250 if (root_id < 0)251 return root_id;252 objagg_obj->root_id = root_id;253 return 0;254}255 256static void objagg_obj_root_id_free(struct objagg *objagg,257 struct objagg_obj *objagg_obj)258{259 if (!objagg->hints)260 return;261 ida_free(&objagg->root_ida, objagg_obj->root_id);262}263 264static int objagg_obj_root_create(struct objagg *objagg,265 struct objagg_obj *objagg_obj,266 struct objagg_hints_node *hnode)267{268 int err;269 270 err = objagg_obj_root_id_alloc(objagg, objagg_obj, hnode);271 if (err)272 return err;273 objagg_obj->root_priv = objagg->ops->root_create(objagg->priv,274 objagg_obj->obj,275 objagg_obj->root_id);276 if (IS_ERR(objagg_obj->root_priv)) {277 err = PTR_ERR(objagg_obj->root_priv);278 goto err_root_create;279 }280 trace_objagg_obj_root_create(objagg, objagg_obj);281 return 0;282 283err_root_create:284 objagg_obj_root_id_free(objagg, objagg_obj);285 return err;286}287 288static void objagg_obj_root_destroy(struct objagg *objagg,289 struct objagg_obj *objagg_obj)290{291 trace_objagg_obj_root_destroy(objagg, objagg_obj);292 objagg->ops->root_destroy(objagg->priv, objagg_obj->root_priv);293 objagg_obj_root_id_free(objagg, objagg_obj);294}295 296static struct objagg_obj *__objagg_obj_get(struct objagg *objagg, void *obj);297 298static int objagg_obj_init_with_hints(struct objagg *objagg,299 struct objagg_obj *objagg_obj,300 bool *hint_found)301{302 struct objagg_hints_node *hnode;303 struct objagg_obj *parent;304 int err;305 306 hnode = objagg_hints_lookup(objagg->hints, objagg_obj->obj);307 if (!hnode) {308 *hint_found = false;309 return 0;310 }311 *hint_found = true;312 313 if (!hnode->parent)314 return objagg_obj_root_create(objagg, objagg_obj, hnode);315 316 parent = __objagg_obj_get(objagg, hnode->parent->obj);317 if (IS_ERR(parent))318 return PTR_ERR(parent);319 320 err = objagg_obj_parent_assign(objagg, objagg_obj, parent, false);321 if (err) {322 *hint_found = false;323 err = 0;324 goto err_parent_assign;325 }326 327 return 0;328 329err_parent_assign:330 objagg_obj_put(objagg, parent);331 return err;332}333 334static int objagg_obj_init(struct objagg *objagg,335 struct objagg_obj *objagg_obj)336{337 bool hint_found;338 int err;339 340 /* First, try to use hints if they are available and341 * if they provide result.342 */343 err = objagg_obj_init_with_hints(objagg, objagg_obj, &hint_found);344 if (err)345 return err;346 347 if (hint_found)348 return 0;349 350 /* Try to find if the object can be aggregated under an existing one. */351 err = objagg_obj_parent_lookup_assign(objagg, objagg_obj);352 if (!err)353 return 0;354 /* If aggregation is not possible, make the object a root. */355 return objagg_obj_root_create(objagg, objagg_obj, NULL);356}357 358static void objagg_obj_fini(struct objagg *objagg,359 struct objagg_obj *objagg_obj)360{361 if (!objagg_obj_is_root(objagg_obj))362 objagg_obj_parent_unassign(objagg, objagg_obj);363 else364 objagg_obj_root_destroy(objagg, objagg_obj);365}366 367static struct objagg_obj *objagg_obj_create(struct objagg *objagg, void *obj)368{369 struct objagg_obj *objagg_obj;370 int err;371 372 objagg_obj = kzalloc(sizeof(*objagg_obj) + objagg->ops->obj_size,373 GFP_KERNEL);374 if (!objagg_obj)375 return ERR_PTR(-ENOMEM);376 objagg_obj_ref_inc(objagg_obj);377 memcpy(objagg_obj->obj, obj, objagg->ops->obj_size);378 379 err = objagg_obj_init(objagg, objagg_obj);380 if (err)381 goto err_obj_init;382 383 err = rhashtable_insert_fast(&objagg->obj_ht, &objagg_obj->ht_node,384 objagg->ht_params);385 if (err)386 goto err_ht_insert;387 list_add(&objagg_obj->list, &objagg->obj_list);388 objagg->obj_count++;389 trace_objagg_obj_create(objagg, objagg_obj);390 391 return objagg_obj;392 393err_ht_insert:394 objagg_obj_fini(objagg, objagg_obj);395err_obj_init:396 kfree(objagg_obj);397 return ERR_PTR(err);398}399 400static struct objagg_obj *__objagg_obj_get(struct objagg *objagg, void *obj)401{402 struct objagg_obj *objagg_obj;403 404 /* First, try to find the object exactly as user passed it,405 * perhaps it is already in use.406 */407 objagg_obj = objagg_obj_lookup(objagg, obj);408 if (objagg_obj) {409 objagg_obj_ref_inc(objagg_obj);410 return objagg_obj;411 }412 413 return objagg_obj_create(objagg, obj);414}415 416/**417 * objagg_obj_get - gets an object within objagg instance418 * @objagg: objagg instance419 * @obj: user-specific private object pointer420 *421 * Note: all locking must be provided by the caller.422 *423 * Size of the "obj" memory is specified in "objagg->ops".424 *425 * There are 3 main options this function wraps:426 * 1) The object according to "obj" already exist. In that case427 * the reference counter is incremented and the object is returned.428 * 2) The object does not exist, but it can be aggregated within429 * another object. In that case, user ops->delta_create() is called430 * to obtain delta data and a new object is created with returned431 * user-delta private pointer.432 * 3) The object does not exist and cannot be aggregated into433 * any of the existing objects. In that case, user ops->root_create()434 * is called to create the root and a new object is created with435 * returned user-root private pointer.436 *437 * Returns a pointer to objagg object instance in case of success,438 * otherwise it returns pointer error using ERR_PTR macro.439 */440struct objagg_obj *objagg_obj_get(struct objagg *objagg, void *obj)441{442 struct objagg_obj *objagg_obj;443 444 objagg_obj = __objagg_obj_get(objagg, obj);445 if (IS_ERR(objagg_obj))446 return objagg_obj;447 objagg_obj_stats_inc(objagg_obj);448 trace_objagg_obj_get(objagg, objagg_obj, objagg_obj->refcount);449 return objagg_obj;450}451EXPORT_SYMBOL(objagg_obj_get);452 453static void objagg_obj_destroy(struct objagg *objagg,454 struct objagg_obj *objagg_obj)455{456 trace_objagg_obj_destroy(objagg, objagg_obj);457 --objagg->obj_count;458 list_del(&objagg_obj->list);459 rhashtable_remove_fast(&objagg->obj_ht, &objagg_obj->ht_node,460 objagg->ht_params);461 objagg_obj_fini(objagg, objagg_obj);462 kfree(objagg_obj);463}464 465static void __objagg_obj_put(struct objagg *objagg,466 struct objagg_obj *objagg_obj)467{468 if (!objagg_obj_ref_dec(objagg_obj))469 objagg_obj_destroy(objagg, objagg_obj);470}471 472/**473 * objagg_obj_put - puts an object within objagg instance474 * @objagg: objagg instance475 * @objagg_obj: objagg object instance476 *477 * Note: all locking must be provided by the caller.478 *479 * Symmetric to objagg_obj_get().480 */481void objagg_obj_put(struct objagg *objagg, struct objagg_obj *objagg_obj)482{483 trace_objagg_obj_put(objagg, objagg_obj, objagg_obj->refcount);484 objagg_obj_stats_dec(objagg_obj);485 __objagg_obj_put(objagg, objagg_obj);486}487EXPORT_SYMBOL(objagg_obj_put);488 489/**490 * objagg_create - creates a new objagg instance491 * @ops: user-specific callbacks492 * @objagg_hints: hints, can be NULL493 * @priv: pointer to a private data passed to the ops494 *495 * Note: all locking must be provided by the caller.496 *497 * The purpose of the library is to provide an infrastructure to498 * aggregate user-specified objects. Library does not care about the type499 * of the object. User fills-up ops which take care of the specific500 * user object manipulation.501 *502 * As a very stupid example, consider integer numbers. For example503 * number 8 as a root object. That can aggregate number 9 with delta 1,504 * number 10 with delta 2, etc. This example is implemented as505 * a part of a testing module in test_objagg.c file.506 *507 * Each objagg instance contains multiple trees. Each tree node is508 * represented by "an object". In the current implementation there can be509 * only roots and leafs nodes. Leaf nodes are called deltas.510 * But in general, this can be easily extended for intermediate nodes.511 * In that extension, a delta would be associated with all non-root512 * nodes.513 *514 * Returns a pointer to newly created objagg instance in case of success,515 * otherwise it returns pointer error using ERR_PTR macro.516 */517struct objagg *objagg_create(const struct objagg_ops *ops,518 struct objagg_hints *objagg_hints, void *priv)519{520 struct objagg *objagg;521 int err;522 523 if (WARN_ON(!ops || !ops->root_create || !ops->root_destroy ||524 !ops->delta_check || !ops->delta_create ||525 !ops->delta_destroy))526 return ERR_PTR(-EINVAL);527 528 objagg = kzalloc(sizeof(*objagg), GFP_KERNEL);529 if (!objagg)530 return ERR_PTR(-ENOMEM);531 objagg->ops = ops;532 if (objagg_hints) {533 objagg->hints = objagg_hints;534 objagg_hints->refcount++;535 }536 objagg->priv = priv;537 INIT_LIST_HEAD(&objagg->obj_list);538 539 objagg->ht_params.key_len = ops->obj_size;540 objagg->ht_params.key_offset = offsetof(struct objagg_obj, obj);541 objagg->ht_params.head_offset = offsetof(struct objagg_obj, ht_node);542 543 err = rhashtable_init(&objagg->obj_ht, &objagg->ht_params);544 if (err)545 goto err_rhashtable_init;546 547 ida_init(&objagg->root_ida);548 549 trace_objagg_create(objagg);550 return objagg;551 552err_rhashtable_init:553 kfree(objagg);554 return ERR_PTR(err);555}556EXPORT_SYMBOL(objagg_create);557 558/**559 * objagg_destroy - destroys a new objagg instance560 * @objagg: objagg instance561 *562 * Note: all locking must be provided by the caller.563 */564void objagg_destroy(struct objagg *objagg)565{566 trace_objagg_destroy(objagg);567 ida_destroy(&objagg->root_ida);568 WARN_ON(!list_empty(&objagg->obj_list));569 rhashtable_destroy(&objagg->obj_ht);570 if (objagg->hints)571 objagg_hints_put(objagg->hints);572 kfree(objagg);573}574EXPORT_SYMBOL(objagg_destroy);575 576static int objagg_stats_info_sort_cmp_func(const void *a, const void *b)577{578 const struct objagg_obj_stats_info *stats_info1 = a;579 const struct objagg_obj_stats_info *stats_info2 = b;580 581 if (stats_info1->is_root != stats_info2->is_root)582 return stats_info2->is_root - stats_info1->is_root;583 if (stats_info1->stats.delta_user_count !=584 stats_info2->stats.delta_user_count)585 return stats_info2->stats.delta_user_count -586 stats_info1->stats.delta_user_count;587 return stats_info2->stats.user_count - stats_info1->stats.user_count;588}589 590/**591 * objagg_stats_get - obtains stats of the objagg instance592 * @objagg: objagg instance593 *594 * Note: all locking must be provided by the caller.595 *596 * The returned structure contains statistics of all object597 * currently in use, ordered by following rules:598 * 1) Root objects are always on lower indexes than the rest.599 * 2) Objects with higher delta user count are always on lower600 * indexes.601 * 3) In case more objects have the same delta user count,602 * the objects are ordered by user count.603 *604 * Returns a pointer to stats instance in case of success,605 * otherwise it returns pointer error using ERR_PTR macro.606 */607const struct objagg_stats *objagg_stats_get(struct objagg *objagg)608{609 struct objagg_stats *objagg_stats;610 struct objagg_obj *objagg_obj;611 int i;612 613 objagg_stats = kzalloc(struct_size(objagg_stats, stats_info,614 objagg->obj_count), GFP_KERNEL);615 if (!objagg_stats)616 return ERR_PTR(-ENOMEM);617 618 i = 0;619 list_for_each_entry(objagg_obj, &objagg->obj_list, list) {620 memcpy(&objagg_stats->stats_info[i].stats, &objagg_obj->stats,621 sizeof(objagg_stats->stats_info[0].stats));622 objagg_stats->stats_info[i].objagg_obj = objagg_obj;623 objagg_stats->stats_info[i].is_root =624 objagg_obj_is_root(objagg_obj);625 if (objagg_stats->stats_info[i].is_root)626 objagg_stats->root_count++;627 i++;628 }629 objagg_stats->stats_info_count = i;630 631 sort(objagg_stats->stats_info, objagg_stats->stats_info_count,632 sizeof(struct objagg_obj_stats_info),633 objagg_stats_info_sort_cmp_func, NULL);634 635 return objagg_stats;636}637EXPORT_SYMBOL(objagg_stats_get);638 639/**640 * objagg_stats_put - puts stats of the objagg instance641 * @objagg_stats: objagg instance stats642 *643 * Note: all locking must be provided by the caller.644 */645void objagg_stats_put(const struct objagg_stats *objagg_stats)646{647 kfree(objagg_stats);648}649EXPORT_SYMBOL(objagg_stats_put);650 651static struct objagg_hints_node *652objagg_hints_node_create(struct objagg_hints *objagg_hints,653 struct objagg_obj *objagg_obj, size_t obj_size,654 struct objagg_hints_node *parent_hnode)655{656 unsigned int user_count = objagg_obj->stats.user_count;657 struct objagg_hints_node *hnode;658 int err;659 660 hnode = kzalloc(sizeof(*hnode) + obj_size, GFP_KERNEL);661 if (!hnode)662 return ERR_PTR(-ENOMEM);663 memcpy(hnode->obj, &objagg_obj->obj, obj_size);664 hnode->stats_info.stats.user_count = user_count;665 hnode->stats_info.stats.delta_user_count = user_count;666 if (parent_hnode) {667 parent_hnode->stats_info.stats.delta_user_count += user_count;668 } else {669 hnode->root_id = objagg_hints->root_count++;670 hnode->stats_info.is_root = true;671 }672 hnode->stats_info.objagg_obj = objagg_obj;673 674 err = rhashtable_insert_fast(&objagg_hints->node_ht, &hnode->ht_node,675 objagg_hints->ht_params);676 if (err)677 goto err_ht_insert;678 679 list_add(&hnode->list, &objagg_hints->node_list);680 hnode->parent = parent_hnode;681 objagg_hints->node_count++;682 683 return hnode;684 685err_ht_insert:686 kfree(hnode);687 return ERR_PTR(err);688}689 690static void objagg_hints_flush(struct objagg_hints *objagg_hints)691{692 struct objagg_hints_node *hnode, *tmp;693 694 list_for_each_entry_safe(hnode, tmp, &objagg_hints->node_list, list) {695 list_del(&hnode->list);696 rhashtable_remove_fast(&objagg_hints->node_ht, &hnode->ht_node,697 objagg_hints->ht_params);698 kfree(hnode);699 }700}701 702struct objagg_tmp_node {703 struct objagg_obj *objagg_obj;704 bool crossed_out;705};706 707struct objagg_tmp_graph {708 struct objagg_tmp_node *nodes;709 unsigned long nodes_count;710 unsigned long *edges;711};712 713static int objagg_tmp_graph_edge_index(struct objagg_tmp_graph *graph,714 int parent_index, int index)715{716 return index * graph->nodes_count + parent_index;717}718 719static void objagg_tmp_graph_edge_set(struct objagg_tmp_graph *graph,720 int parent_index, int index)721{722 int edge_index = objagg_tmp_graph_edge_index(graph, index,723 parent_index);724 725 __set_bit(edge_index, graph->edges);726}727 728static bool objagg_tmp_graph_is_edge(struct objagg_tmp_graph *graph,729 int parent_index, int index)730{731 int edge_index = objagg_tmp_graph_edge_index(graph, index,732 parent_index);733 734 return test_bit(edge_index, graph->edges);735}736 737static unsigned int objagg_tmp_graph_node_weight(struct objagg_tmp_graph *graph,738 unsigned int index)739{740 struct objagg_tmp_node *node = &graph->nodes[index];741 unsigned int weight = node->objagg_obj->stats.user_count;742 int j;743 744 /* Node weight is sum of node users and all other nodes users745 * that this node can represent with delta.746 */747 748 for (j = 0; j < graph->nodes_count; j++) {749 if (!objagg_tmp_graph_is_edge(graph, index, j))750 continue;751 node = &graph->nodes[j];752 if (node->crossed_out)753 continue;754 weight += node->objagg_obj->stats.user_count;755 }756 return weight;757}758 759static int objagg_tmp_graph_node_max_weight(struct objagg_tmp_graph *graph)760{761 struct objagg_tmp_node *node;762 unsigned int max_weight = 0;763 unsigned int weight;764 int max_index = -1;765 int i;766 767 for (i = 0; i < graph->nodes_count; i++) {768 node = &graph->nodes[i];769 if (node->crossed_out)770 continue;771 weight = objagg_tmp_graph_node_weight(graph, i);772 if (weight >= max_weight) {773 max_weight = weight;774 max_index = i;775 }776 }777 return max_index;778}779 780static struct objagg_tmp_graph *objagg_tmp_graph_create(struct objagg *objagg)781{782 unsigned int nodes_count = objagg->obj_count;783 struct objagg_tmp_graph *graph;784 struct objagg_tmp_node *node;785 struct objagg_tmp_node *pnode;786 struct objagg_obj *objagg_obj;787 int i, j;788 789 graph = kzalloc(sizeof(*graph), GFP_KERNEL);790 if (!graph)791 return NULL;792 793 graph->nodes = kcalloc(nodes_count, sizeof(*graph->nodes), GFP_KERNEL);794 if (!graph->nodes)795 goto err_nodes_alloc;796 graph->nodes_count = nodes_count;797 798 graph->edges = bitmap_zalloc(nodes_count * nodes_count, GFP_KERNEL);799 if (!graph->edges)800 goto err_edges_alloc;801 802 i = 0;803 list_for_each_entry(objagg_obj, &objagg->obj_list, list) {804 node = &graph->nodes[i++];805 node->objagg_obj = objagg_obj;806 }807 808 /* Assemble a temporary graph. Insert edge X->Y in case Y can be809 * in delta of X.810 */811 for (i = 0; i < nodes_count; i++) {812 for (j = 0; j < nodes_count; j++) {813 if (i == j)814 continue;815 pnode = &graph->nodes[i];816 node = &graph->nodes[j];817 if (objagg->ops->delta_check(objagg->priv,818 pnode->objagg_obj->obj,819 node->objagg_obj->obj)) {820 objagg_tmp_graph_edge_set(graph, i, j);821 822 }823 }824 }825 return graph;826 827err_edges_alloc:828 kfree(graph->nodes);829err_nodes_alloc:830 kfree(graph);831 return NULL;832}833 834static void objagg_tmp_graph_destroy(struct objagg_tmp_graph *graph)835{836 bitmap_free(graph->edges);837 kfree(graph->nodes);838 kfree(graph);839}840 841static int842objagg_opt_simple_greedy_fillup_hints(struct objagg_hints *objagg_hints,843 struct objagg *objagg)844{845 struct objagg_hints_node *hnode, *parent_hnode;846 struct objagg_tmp_graph *graph;847 struct objagg_tmp_node *node;848 int index;849 int j;850 int err;851 852 graph = objagg_tmp_graph_create(objagg);853 if (!graph)854 return -ENOMEM;855 856 /* Find the nodes from the ones that can accommodate most users857 * and cross them out of the graph. Save them to the hint list.858 */859 while ((index = objagg_tmp_graph_node_max_weight(graph)) != -1) {860 node = &graph->nodes[index];861 node->crossed_out = true;862 hnode = objagg_hints_node_create(objagg_hints,863 node->objagg_obj,864 objagg->ops->obj_size,865 NULL);866 if (IS_ERR(hnode)) {867 err = PTR_ERR(hnode);868 goto out;869 }870 parent_hnode = hnode;871 for (j = 0; j < graph->nodes_count; j++) {872 if (!objagg_tmp_graph_is_edge(graph, index, j))873 continue;874 node = &graph->nodes[j];875 if (node->crossed_out)876 continue;877 node->crossed_out = true;878 hnode = objagg_hints_node_create(objagg_hints,879 node->objagg_obj,880 objagg->ops->obj_size,881 parent_hnode);882 if (IS_ERR(hnode)) {883 err = PTR_ERR(hnode);884 goto out;885 }886 }887 }888 889 err = 0;890out:891 objagg_tmp_graph_destroy(graph);892 return err;893}894 895struct objagg_opt_algo {896 int (*fillup_hints)(struct objagg_hints *objagg_hints,897 struct objagg *objagg);898};899 900static const struct objagg_opt_algo objagg_opt_simple_greedy = {901 .fillup_hints = objagg_opt_simple_greedy_fillup_hints,902};903 904 905static const struct objagg_opt_algo *objagg_opt_algos[] = {906 [OBJAGG_OPT_ALGO_SIMPLE_GREEDY] = &objagg_opt_simple_greedy,907};908 909/**910 * objagg_hints_get - obtains hints instance911 * @objagg: objagg instance912 * @opt_algo_type: type of hints finding algorithm913 *914 * Note: all locking must be provided by the caller.915 *916 * According to the algo type, the existing objects of objagg instance917 * are going to be went-through to assemble an optimal tree. We call this918 * tree hints. These hints can be later on used for creation of919 * a new objagg instance. There, the future object creations are going920 * to be consulted with these hints in order to find out, where exactly921 * the new object should be put as a root or delta.922 *923 * Returns a pointer to hints instance in case of success,924 * otherwise it returns pointer error using ERR_PTR macro.925 */926struct objagg_hints *objagg_hints_get(struct objagg *objagg,927 enum objagg_opt_algo_type opt_algo_type)928{929 const struct objagg_opt_algo *algo = objagg_opt_algos[opt_algo_type];930 struct objagg_hints *objagg_hints;931 int err;932 933 objagg_hints = kzalloc(sizeof(*objagg_hints), GFP_KERNEL);934 if (!objagg_hints)935 return ERR_PTR(-ENOMEM);936 937 objagg_hints->ops = objagg->ops;938 objagg_hints->refcount = 1;939 940 INIT_LIST_HEAD(&objagg_hints->node_list);941 942 objagg_hints->ht_params.key_len = objagg->ops->obj_size;943 objagg_hints->ht_params.key_offset =944 offsetof(struct objagg_hints_node, obj);945 objagg_hints->ht_params.head_offset =946 offsetof(struct objagg_hints_node, ht_node);947 948 err = rhashtable_init(&objagg_hints->node_ht, &objagg_hints->ht_params);949 if (err)950 goto err_rhashtable_init;951 952 err = algo->fillup_hints(objagg_hints, objagg);953 if (err)954 goto err_fillup_hints;955 956 if (WARN_ON(objagg_hints->node_count != objagg->obj_count)) {957 err = -EINVAL;958 goto err_node_count_check;959 }960 961 return objagg_hints;962 963err_node_count_check:964err_fillup_hints:965 objagg_hints_flush(objagg_hints);966 rhashtable_destroy(&objagg_hints->node_ht);967err_rhashtable_init:968 kfree(objagg_hints);969 return ERR_PTR(err);970}971EXPORT_SYMBOL(objagg_hints_get);972 973/**974 * objagg_hints_put - puts hints instance975 * @objagg_hints: objagg hints instance976 *977 * Note: all locking must be provided by the caller.978 */979void objagg_hints_put(struct objagg_hints *objagg_hints)980{981 if (--objagg_hints->refcount)982 return;983 objagg_hints_flush(objagg_hints);984 rhashtable_destroy(&objagg_hints->node_ht);985 kfree(objagg_hints);986}987EXPORT_SYMBOL(objagg_hints_put);988 989/**990 * objagg_hints_stats_get - obtains stats of the hints instance991 * @objagg_hints: hints instance992 *993 * Note: all locking must be provided by the caller.994 *995 * The returned structure contains statistics of all objects996 * currently in use, ordered by following rules:997 * 1) Root objects are always on lower indexes than the rest.998 * 2) Objects with higher delta user count are always on lower999 * indexes.1000 * 3) In case multiple objects have the same delta user count,1001 * the objects are ordered by user count.1002 *1003 * Returns a pointer to stats instance in case of success,1004 * otherwise it returns pointer error using ERR_PTR macro.1005 */1006const struct objagg_stats *1007objagg_hints_stats_get(struct objagg_hints *objagg_hints)1008{1009 struct objagg_stats *objagg_stats;1010 struct objagg_hints_node *hnode;1011 int i;1012 1013 objagg_stats = kzalloc(struct_size(objagg_stats, stats_info,1014 objagg_hints->node_count),1015 GFP_KERNEL);1016 if (!objagg_stats)1017 return ERR_PTR(-ENOMEM);1018 1019 i = 0;1020 list_for_each_entry(hnode, &objagg_hints->node_list, list) {1021 memcpy(&objagg_stats->stats_info[i], &hnode->stats_info,1022 sizeof(objagg_stats->stats_info[0]));1023 if (objagg_stats->stats_info[i].is_root)1024 objagg_stats->root_count++;1025 i++;1026 }1027 objagg_stats->stats_info_count = i;1028 1029 sort(objagg_stats->stats_info, objagg_stats->stats_info_count,1030 sizeof(struct objagg_obj_stats_info),1031 objagg_stats_info_sort_cmp_func, NULL);1032 1033 return objagg_stats;1034}1035EXPORT_SYMBOL(objagg_hints_stats_get);1036 1037MODULE_LICENSE("Dual BSD/GPL");1038MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");1039MODULE_DESCRIPTION("Object aggregation manager");1040