1440 lines · c
1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * cgroups support for the BFQ I/O scheduler.4 */5#include <linux/module.h>6#include <linux/slab.h>7#include <linux/blkdev.h>8#include <linux/cgroup.h>9#include <linux/ktime.h>10#include <linux/rbtree.h>11#include <linux/ioprio.h>12#include <linux/sbitmap.h>13#include <linux/delay.h>14 15#include "elevator.h"16#include "bfq-iosched.h"17 18#ifdef CONFIG_BFQ_CGROUP_DEBUG19static int bfq_stat_init(struct bfq_stat *stat, gfp_t gfp)20{21 int ret;22 23 ret = percpu_counter_init(&stat->cpu_cnt, 0, gfp);24 if (ret)25 return ret;26 27 atomic64_set(&stat->aux_cnt, 0);28 return 0;29}30 31static void bfq_stat_exit(struct bfq_stat *stat)32{33 percpu_counter_destroy(&stat->cpu_cnt);34}35 36/**37 * bfq_stat_add - add a value to a bfq_stat38 * @stat: target bfq_stat39 * @val: value to add40 *41 * Add @val to @stat. The caller must ensure that IRQ on the same CPU42 * don't re-enter this function for the same counter.43 */44static inline void bfq_stat_add(struct bfq_stat *stat, uint64_t val)45{46 percpu_counter_add_batch(&stat->cpu_cnt, val, BLKG_STAT_CPU_BATCH);47}48 49/**50 * bfq_stat_read - read the current value of a bfq_stat51 * @stat: bfq_stat to read52 */53static inline uint64_t bfq_stat_read(struct bfq_stat *stat)54{55 return percpu_counter_sum_positive(&stat->cpu_cnt);56}57 58/**59 * bfq_stat_reset - reset a bfq_stat60 * @stat: bfq_stat to reset61 */62static inline void bfq_stat_reset(struct bfq_stat *stat)63{64 percpu_counter_set(&stat->cpu_cnt, 0);65 atomic64_set(&stat->aux_cnt, 0);66}67 68/**69 * bfq_stat_add_aux - add a bfq_stat into another's aux count70 * @to: the destination bfq_stat71 * @from: the source72 *73 * Add @from's count including the aux one to @to's aux count.74 */75static inline void bfq_stat_add_aux(struct bfq_stat *to,76 struct bfq_stat *from)77{78 atomic64_add(bfq_stat_read(from) + atomic64_read(&from->aux_cnt),79 &to->aux_cnt);80}81 82/**83 * blkg_prfill_stat - prfill callback for bfq_stat84 * @sf: seq_file to print to85 * @pd: policy private data of interest86 * @off: offset to the bfq_stat in @pd87 *88 * prfill callback for printing a bfq_stat.89 */90static u64 blkg_prfill_stat(struct seq_file *sf, struct blkg_policy_data *pd,91 int off)92{93 return __blkg_prfill_u64(sf, pd, bfq_stat_read((void *)pd + off));94}95 96/* bfqg stats flags */97enum bfqg_stats_flags {98 BFQG_stats_waiting = 0,99 BFQG_stats_idling,100 BFQG_stats_empty,101};102 103#define BFQG_FLAG_FNS(name) \104static void bfqg_stats_mark_##name(struct bfqg_stats *stats) \105{ \106 stats->flags |= (1 << BFQG_stats_##name); \107} \108static void bfqg_stats_clear_##name(struct bfqg_stats *stats) \109{ \110 stats->flags &= ~(1 << BFQG_stats_##name); \111} \112static int bfqg_stats_##name(struct bfqg_stats *stats) \113{ \114 return (stats->flags & (1 << BFQG_stats_##name)) != 0; \115} \116 117BFQG_FLAG_FNS(waiting)118BFQG_FLAG_FNS(idling)119BFQG_FLAG_FNS(empty)120#undef BFQG_FLAG_FNS121 122/* This should be called with the scheduler lock held. */123static void bfqg_stats_update_group_wait_time(struct bfqg_stats *stats)124{125 u64 now;126 127 if (!bfqg_stats_waiting(stats))128 return;129 130 now = blk_time_get_ns();131 if (now > stats->start_group_wait_time)132 bfq_stat_add(&stats->group_wait_time,133 now - stats->start_group_wait_time);134 bfqg_stats_clear_waiting(stats);135}136 137/* This should be called with the scheduler lock held. */138static void bfqg_stats_set_start_group_wait_time(struct bfq_group *bfqg,139 struct bfq_group *curr_bfqg)140{141 struct bfqg_stats *stats = &bfqg->stats;142 143 if (bfqg_stats_waiting(stats))144 return;145 if (bfqg == curr_bfqg)146 return;147 stats->start_group_wait_time = blk_time_get_ns();148 bfqg_stats_mark_waiting(stats);149}150 151/* This should be called with the scheduler lock held. */152static void bfqg_stats_end_empty_time(struct bfqg_stats *stats)153{154 u64 now;155 156 if (!bfqg_stats_empty(stats))157 return;158 159 now = blk_time_get_ns();160 if (now > stats->start_empty_time)161 bfq_stat_add(&stats->empty_time,162 now - stats->start_empty_time);163 bfqg_stats_clear_empty(stats);164}165 166void bfqg_stats_update_dequeue(struct bfq_group *bfqg)167{168 bfq_stat_add(&bfqg->stats.dequeue, 1);169}170 171void bfqg_stats_set_start_empty_time(struct bfq_group *bfqg)172{173 struct bfqg_stats *stats = &bfqg->stats;174 175 if (blkg_rwstat_total(&stats->queued))176 return;177 178 /*179 * group is already marked empty. This can happen if bfqq got new180 * request in parent group and moved to this group while being added181 * to service tree. Just ignore the event and move on.182 */183 if (bfqg_stats_empty(stats))184 return;185 186 stats->start_empty_time = blk_time_get_ns();187 bfqg_stats_mark_empty(stats);188}189 190void bfqg_stats_update_idle_time(struct bfq_group *bfqg)191{192 struct bfqg_stats *stats = &bfqg->stats;193 194 if (bfqg_stats_idling(stats)) {195 u64 now = blk_time_get_ns();196 197 if (now > stats->start_idle_time)198 bfq_stat_add(&stats->idle_time,199 now - stats->start_idle_time);200 bfqg_stats_clear_idling(stats);201 }202}203 204void bfqg_stats_set_start_idle_time(struct bfq_group *bfqg)205{206 struct bfqg_stats *stats = &bfqg->stats;207 208 stats->start_idle_time = blk_time_get_ns();209 bfqg_stats_mark_idling(stats);210}211 212void bfqg_stats_update_avg_queue_size(struct bfq_group *bfqg)213{214 struct bfqg_stats *stats = &bfqg->stats;215 216 bfq_stat_add(&stats->avg_queue_size_sum,217 blkg_rwstat_total(&stats->queued));218 bfq_stat_add(&stats->avg_queue_size_samples, 1);219 bfqg_stats_update_group_wait_time(stats);220}221 222void bfqg_stats_update_io_add(struct bfq_group *bfqg, struct bfq_queue *bfqq,223 blk_opf_t opf)224{225 blkg_rwstat_add(&bfqg->stats.queued, opf, 1);226 bfqg_stats_end_empty_time(&bfqg->stats);227 if (!(bfqq == bfqg->bfqd->in_service_queue))228 bfqg_stats_set_start_group_wait_time(bfqg, bfqq_group(bfqq));229}230 231void bfqg_stats_update_io_remove(struct bfq_group *bfqg, blk_opf_t opf)232{233 blkg_rwstat_add(&bfqg->stats.queued, opf, -1);234}235 236void bfqg_stats_update_io_merged(struct bfq_group *bfqg, blk_opf_t opf)237{238 blkg_rwstat_add(&bfqg->stats.merged, opf, 1);239}240 241void bfqg_stats_update_completion(struct bfq_group *bfqg, u64 start_time_ns,242 u64 io_start_time_ns, blk_opf_t opf)243{244 struct bfqg_stats *stats = &bfqg->stats;245 u64 now = blk_time_get_ns();246 247 if (now > io_start_time_ns)248 blkg_rwstat_add(&stats->service_time, opf,249 now - io_start_time_ns);250 if (io_start_time_ns > start_time_ns)251 blkg_rwstat_add(&stats->wait_time, opf,252 io_start_time_ns - start_time_ns);253}254 255#else /* CONFIG_BFQ_CGROUP_DEBUG */256 257void bfqg_stats_update_io_remove(struct bfq_group *bfqg, blk_opf_t opf) { }258void bfqg_stats_update_io_merged(struct bfq_group *bfqg, blk_opf_t opf) { }259void bfqg_stats_update_completion(struct bfq_group *bfqg, u64 start_time_ns,260 u64 io_start_time_ns, blk_opf_t opf) { }261void bfqg_stats_update_dequeue(struct bfq_group *bfqg) { }262void bfqg_stats_set_start_idle_time(struct bfq_group *bfqg) { }263 264#endif /* CONFIG_BFQ_CGROUP_DEBUG */265 266#ifdef CONFIG_BFQ_GROUP_IOSCHED267 268/*269 * blk-cgroup policy-related handlers270 * The following functions help in converting between blk-cgroup271 * internal structures and BFQ-specific structures.272 */273 274static struct bfq_group *pd_to_bfqg(struct blkg_policy_data *pd)275{276 return pd ? container_of(pd, struct bfq_group, pd) : NULL;277}278 279struct blkcg_gq *bfqg_to_blkg(struct bfq_group *bfqg)280{281 return pd_to_blkg(&bfqg->pd);282}283 284static struct bfq_group *blkg_to_bfqg(struct blkcg_gq *blkg)285{286 return pd_to_bfqg(blkg_to_pd(blkg, &blkcg_policy_bfq));287}288 289/*290 * bfq_group handlers291 * The following functions help in navigating the bfq_group hierarchy292 * by allowing to find the parent of a bfq_group or the bfq_group293 * associated to a bfq_queue.294 */295 296static struct bfq_group *bfqg_parent(struct bfq_group *bfqg)297{298 struct blkcg_gq *pblkg = bfqg_to_blkg(bfqg)->parent;299 300 return pblkg ? blkg_to_bfqg(pblkg) : NULL;301}302 303struct bfq_group *bfqq_group(struct bfq_queue *bfqq)304{305 struct bfq_entity *group_entity = bfqq->entity.parent;306 307 return group_entity ? container_of(group_entity, struct bfq_group,308 entity) :309 bfqq->bfqd->root_group;310}311 312/*313 * The following two functions handle get and put of a bfq_group by314 * wrapping the related blk-cgroup hooks.315 */316 317static void bfqg_get(struct bfq_group *bfqg)318{319 refcount_inc(&bfqg->ref);320}321 322static void bfqg_put(struct bfq_group *bfqg)323{324 if (refcount_dec_and_test(&bfqg->ref))325 kfree(bfqg);326}327 328static void bfqg_and_blkg_get(struct bfq_group *bfqg)329{330 /* see comments in bfq_bic_update_cgroup for why refcounting bfqg */331 bfqg_get(bfqg);332 333 blkg_get(bfqg_to_blkg(bfqg));334}335 336void bfqg_and_blkg_put(struct bfq_group *bfqg)337{338 blkg_put(bfqg_to_blkg(bfqg));339 340 bfqg_put(bfqg);341}342 343void bfqg_stats_update_legacy_io(struct request_queue *q, struct request *rq)344{345 struct bfq_group *bfqg = blkg_to_bfqg(rq->bio->bi_blkg);346 347 if (!bfqg)348 return;349 350 blkg_rwstat_add(&bfqg->stats.bytes, rq->cmd_flags, blk_rq_bytes(rq));351 blkg_rwstat_add(&bfqg->stats.ios, rq->cmd_flags, 1);352}353 354/* @stats = 0 */355static void bfqg_stats_reset(struct bfqg_stats *stats)356{357#ifdef CONFIG_BFQ_CGROUP_DEBUG358 /* queued stats shouldn't be cleared */359 blkg_rwstat_reset(&stats->merged);360 blkg_rwstat_reset(&stats->service_time);361 blkg_rwstat_reset(&stats->wait_time);362 bfq_stat_reset(&stats->time);363 bfq_stat_reset(&stats->avg_queue_size_sum);364 bfq_stat_reset(&stats->avg_queue_size_samples);365 bfq_stat_reset(&stats->dequeue);366 bfq_stat_reset(&stats->group_wait_time);367 bfq_stat_reset(&stats->idle_time);368 bfq_stat_reset(&stats->empty_time);369#endif370}371 372/* @to += @from */373static void bfqg_stats_add_aux(struct bfqg_stats *to, struct bfqg_stats *from)374{375 if (!to || !from)376 return;377 378#ifdef CONFIG_BFQ_CGROUP_DEBUG379 /* queued stats shouldn't be cleared */380 blkg_rwstat_add_aux(&to->merged, &from->merged);381 blkg_rwstat_add_aux(&to->service_time, &from->service_time);382 blkg_rwstat_add_aux(&to->wait_time, &from->wait_time);383 bfq_stat_add_aux(&from->time, &from->time);384 bfq_stat_add_aux(&to->avg_queue_size_sum, &from->avg_queue_size_sum);385 bfq_stat_add_aux(&to->avg_queue_size_samples,386 &from->avg_queue_size_samples);387 bfq_stat_add_aux(&to->dequeue, &from->dequeue);388 bfq_stat_add_aux(&to->group_wait_time, &from->group_wait_time);389 bfq_stat_add_aux(&to->idle_time, &from->idle_time);390 bfq_stat_add_aux(&to->empty_time, &from->empty_time);391#endif392}393 394/*395 * Transfer @bfqg's stats to its parent's aux counts so that the ancestors'396 * recursive stats can still account for the amount used by this bfqg after397 * it's gone.398 */399static void bfqg_stats_xfer_dead(struct bfq_group *bfqg)400{401 struct bfq_group *parent;402 403 if (!bfqg) /* root_group */404 return;405 406 parent = bfqg_parent(bfqg);407 408 lockdep_assert_held(&bfqg_to_blkg(bfqg)->q->queue_lock);409 410 if (unlikely(!parent))411 return;412 413 bfqg_stats_add_aux(&parent->stats, &bfqg->stats);414 bfqg_stats_reset(&bfqg->stats);415}416 417void bfq_init_entity(struct bfq_entity *entity, struct bfq_group *bfqg)418{419 struct bfq_queue *bfqq = bfq_entity_to_bfqq(entity);420 421 entity->weight = entity->new_weight;422 entity->orig_weight = entity->new_weight;423 if (bfqq) {424 bfqq->ioprio = bfqq->new_ioprio;425 bfqq->ioprio_class = bfqq->new_ioprio_class;426 /*427 * Make sure that bfqg and its associated blkg do not428 * disappear before entity.429 */430 bfqg_and_blkg_get(bfqg);431 }432 entity->parent = bfqg->my_entity; /* NULL for root group */433 entity->sched_data = &bfqg->sched_data;434}435 436static void bfqg_stats_exit(struct bfqg_stats *stats)437{438 blkg_rwstat_exit(&stats->bytes);439 blkg_rwstat_exit(&stats->ios);440#ifdef CONFIG_BFQ_CGROUP_DEBUG441 blkg_rwstat_exit(&stats->merged);442 blkg_rwstat_exit(&stats->service_time);443 blkg_rwstat_exit(&stats->wait_time);444 blkg_rwstat_exit(&stats->queued);445 bfq_stat_exit(&stats->time);446 bfq_stat_exit(&stats->avg_queue_size_sum);447 bfq_stat_exit(&stats->avg_queue_size_samples);448 bfq_stat_exit(&stats->dequeue);449 bfq_stat_exit(&stats->group_wait_time);450 bfq_stat_exit(&stats->idle_time);451 bfq_stat_exit(&stats->empty_time);452#endif453}454 455static int bfqg_stats_init(struct bfqg_stats *stats, gfp_t gfp)456{457 if (blkg_rwstat_init(&stats->bytes, gfp) ||458 blkg_rwstat_init(&stats->ios, gfp))459 goto error;460 461#ifdef CONFIG_BFQ_CGROUP_DEBUG462 if (blkg_rwstat_init(&stats->merged, gfp) ||463 blkg_rwstat_init(&stats->service_time, gfp) ||464 blkg_rwstat_init(&stats->wait_time, gfp) ||465 blkg_rwstat_init(&stats->queued, gfp) ||466 bfq_stat_init(&stats->time, gfp) ||467 bfq_stat_init(&stats->avg_queue_size_sum, gfp) ||468 bfq_stat_init(&stats->avg_queue_size_samples, gfp) ||469 bfq_stat_init(&stats->dequeue, gfp) ||470 bfq_stat_init(&stats->group_wait_time, gfp) ||471 bfq_stat_init(&stats->idle_time, gfp) ||472 bfq_stat_init(&stats->empty_time, gfp))473 goto error;474#endif475 476 return 0;477 478error:479 bfqg_stats_exit(stats);480 return -ENOMEM;481}482 483static struct bfq_group_data *cpd_to_bfqgd(struct blkcg_policy_data *cpd)484{485 return cpd ? container_of(cpd, struct bfq_group_data, pd) : NULL;486}487 488static struct bfq_group_data *blkcg_to_bfqgd(struct blkcg *blkcg)489{490 return cpd_to_bfqgd(blkcg_to_cpd(blkcg, &blkcg_policy_bfq));491}492 493static struct blkcg_policy_data *bfq_cpd_alloc(gfp_t gfp)494{495 struct bfq_group_data *bgd;496 497 bgd = kzalloc(sizeof(*bgd), gfp);498 if (!bgd)499 return NULL;500 501 bgd->weight = CGROUP_WEIGHT_DFL;502 return &bgd->pd;503}504 505static void bfq_cpd_free(struct blkcg_policy_data *cpd)506{507 kfree(cpd_to_bfqgd(cpd));508}509 510static struct blkg_policy_data *bfq_pd_alloc(struct gendisk *disk,511 struct blkcg *blkcg, gfp_t gfp)512{513 struct bfq_group *bfqg;514 515 bfqg = kzalloc_node(sizeof(*bfqg), gfp, disk->node_id);516 if (!bfqg)517 return NULL;518 519 if (bfqg_stats_init(&bfqg->stats, gfp)) {520 kfree(bfqg);521 return NULL;522 }523 524 /* see comments in bfq_bic_update_cgroup for why refcounting */525 refcount_set(&bfqg->ref, 1);526 return &bfqg->pd;527}528 529static void bfq_pd_init(struct blkg_policy_data *pd)530{531 struct blkcg_gq *blkg = pd_to_blkg(pd);532 struct bfq_group *bfqg = blkg_to_bfqg(blkg);533 struct bfq_data *bfqd = blkg->q->elevator->elevator_data;534 struct bfq_entity *entity = &bfqg->entity;535 struct bfq_group_data *d = blkcg_to_bfqgd(blkg->blkcg);536 537 entity->orig_weight = entity->weight = entity->new_weight = d->weight;538 entity->my_sched_data = &bfqg->sched_data;539 entity->last_bfqq_created = NULL;540 541 bfqg->my_entity = entity; /*542 * the root_group's will be set to NULL543 * in bfq_init_queue()544 */545 bfqg->bfqd = bfqd;546 bfqg->active_entities = 0;547 bfqg->num_queues_with_pending_reqs = 0;548 bfqg->rq_pos_tree = RB_ROOT;549}550 551static void bfq_pd_free(struct blkg_policy_data *pd)552{553 struct bfq_group *bfqg = pd_to_bfqg(pd);554 555 bfqg_stats_exit(&bfqg->stats);556 bfqg_put(bfqg);557}558 559static void bfq_pd_reset_stats(struct blkg_policy_data *pd)560{561 struct bfq_group *bfqg = pd_to_bfqg(pd);562 563 bfqg_stats_reset(&bfqg->stats);564}565 566static void bfq_group_set_parent(struct bfq_group *bfqg,567 struct bfq_group *parent)568{569 struct bfq_entity *entity;570 571 entity = &bfqg->entity;572 entity->parent = parent->my_entity;573 entity->sched_data = &parent->sched_data;574}575 576static void bfq_link_bfqg(struct bfq_data *bfqd, struct bfq_group *bfqg)577{578 struct bfq_group *parent;579 struct bfq_entity *entity;580 581 /*582 * Update chain of bfq_groups as we might be handling a leaf group583 * which, along with some of its relatives, has not been hooked yet584 * to the private hierarchy of BFQ.585 */586 entity = &bfqg->entity;587 for_each_entity(entity) {588 struct bfq_group *curr_bfqg = container_of(entity,589 struct bfq_group, entity);590 if (curr_bfqg != bfqd->root_group) {591 parent = bfqg_parent(curr_bfqg);592 if (!parent)593 parent = bfqd->root_group;594 bfq_group_set_parent(curr_bfqg, parent);595 }596 }597}598 599struct bfq_group *bfq_bio_bfqg(struct bfq_data *bfqd, struct bio *bio)600{601 struct blkcg_gq *blkg = bio->bi_blkg;602 struct bfq_group *bfqg;603 604 while (blkg) {605 if (!blkg->online) {606 blkg = blkg->parent;607 continue;608 }609 bfqg = blkg_to_bfqg(blkg);610 if (bfqg->pd.online) {611 bio_associate_blkg_from_css(bio, &blkg->blkcg->css);612 return bfqg;613 }614 blkg = blkg->parent;615 }616 bio_associate_blkg_from_css(bio,617 &bfqg_to_blkg(bfqd->root_group)->blkcg->css);618 return bfqd->root_group;619}620 621/**622 * bfq_bfqq_move - migrate @bfqq to @bfqg.623 * @bfqd: queue descriptor.624 * @bfqq: the queue to move.625 * @bfqg: the group to move to.626 *627 * Move @bfqq to @bfqg, deactivating it from its old group and reactivating628 * it on the new one. Avoid putting the entity on the old group idle tree.629 *630 * Must be called under the scheduler lock, to make sure that the blkg631 * owning @bfqg does not disappear (see comments in632 * bfq_bic_update_cgroup on guaranteeing the consistency of blkg633 * objects).634 */635void bfq_bfqq_move(struct bfq_data *bfqd, struct bfq_queue *bfqq,636 struct bfq_group *bfqg)637{638 struct bfq_entity *entity = &bfqq->entity;639 struct bfq_group *old_parent = bfqq_group(bfqq);640 bool has_pending_reqs = false;641 642 /*643 * No point to move bfqq to the same group, which can happen when644 * root group is offlined645 */646 if (old_parent == bfqg)647 return;648 649 /*650 * oom_bfqq is not allowed to move, oom_bfqq will hold ref to root_group651 * until elevator exit.652 */653 if (bfqq == &bfqd->oom_bfqq)654 return;655 /*656 * Get extra reference to prevent bfqq from being freed in657 * next possible expire or deactivate.658 */659 bfqq->ref++;660 661 if (entity->in_groups_with_pending_reqs) {662 has_pending_reqs = true;663 bfq_del_bfqq_in_groups_with_pending_reqs(bfqq);664 }665 666 /* If bfqq is empty, then bfq_bfqq_expire also invokes667 * bfq_del_bfqq_busy, thereby removing bfqq and its entity668 * from data structures related to current group. Otherwise we669 * need to remove bfqq explicitly with bfq_deactivate_bfqq, as670 * we do below.671 */672 if (bfqq == bfqd->in_service_queue)673 bfq_bfqq_expire(bfqd, bfqd->in_service_queue,674 false, BFQQE_PREEMPTED);675 676 if (bfq_bfqq_busy(bfqq))677 bfq_deactivate_bfqq(bfqd, bfqq, false, false);678 else if (entity->on_st_or_in_serv)679 bfq_put_idle_entity(bfq_entity_service_tree(entity), entity);680 bfqg_and_blkg_put(old_parent);681 682 bfq_reassign_last_bfqq(bfqq, NULL);683 entity->parent = bfqg->my_entity;684 entity->sched_data = &bfqg->sched_data;685 /* pin down bfqg and its associated blkg */686 bfqg_and_blkg_get(bfqg);687 688 if (has_pending_reqs)689 bfq_add_bfqq_in_groups_with_pending_reqs(bfqq);690 691 if (bfq_bfqq_busy(bfqq)) {692 if (unlikely(!bfqd->nonrot_with_queueing))693 bfq_pos_tree_add_move(bfqd, bfqq);694 bfq_activate_bfqq(bfqd, bfqq);695 }696 697 if (!bfqd->in_service_queue && !bfqd->tot_rq_in_driver)698 bfq_schedule_dispatch(bfqd);699 /* release extra ref taken above, bfqq may happen to be freed now */700 bfq_put_queue(bfqq);701}702 703static void bfq_sync_bfqq_move(struct bfq_data *bfqd,704 struct bfq_queue *sync_bfqq,705 struct bfq_io_cq *bic,706 struct bfq_group *bfqg,707 unsigned int act_idx)708{709 struct bfq_queue *bfqq;710 711 if (!sync_bfqq->new_bfqq && !bfq_bfqq_coop(sync_bfqq)) {712 /* We are the only user of this bfqq, just move it */713 if (sync_bfqq->entity.sched_data != &bfqg->sched_data)714 bfq_bfqq_move(bfqd, sync_bfqq, bfqg);715 return;716 }717 718 /*719 * The queue was merged to a different queue. Check720 * that the merge chain still belongs to the same721 * cgroup.722 */723 for (bfqq = sync_bfqq; bfqq; bfqq = bfqq->new_bfqq)724 if (bfqq->entity.sched_data != &bfqg->sched_data)725 break;726 if (bfqq) {727 /*728 * Some queue changed cgroup so the merge is not valid729 * anymore. We cannot easily just cancel the merge (by730 * clearing new_bfqq) as there may be other processes731 * using this queue and holding refs to all queues732 * below sync_bfqq->new_bfqq. Similarly if the merge733 * already happened, we need to detach from bfqq now734 * so that we cannot merge bio to a request from the735 * old cgroup.736 */737 bfq_put_cooperator(sync_bfqq);738 bic_set_bfqq(bic, NULL, true, act_idx);739 }740}741 742/**743 * __bfq_bic_change_cgroup - move @bic to @bfqg.744 * @bfqd: the queue descriptor.745 * @bic: the bic to move.746 * @bfqg: the group to move to.747 *748 * Move bic to blkcg, assuming that bfqd->lock is held; which makes749 * sure that the reference to cgroup is valid across the call (see750 * comments in bfq_bic_update_cgroup on this issue)751 */752static void __bfq_bic_change_cgroup(struct bfq_data *bfqd,753 struct bfq_io_cq *bic,754 struct bfq_group *bfqg)755{756 unsigned int act_idx;757 758 for (act_idx = 0; act_idx < bfqd->num_actuators; act_idx++) {759 struct bfq_queue *async_bfqq = bic_to_bfqq(bic, false, act_idx);760 struct bfq_queue *sync_bfqq = bic_to_bfqq(bic, true, act_idx);761 762 if (async_bfqq &&763 async_bfqq->entity.sched_data != &bfqg->sched_data) {764 bic_set_bfqq(bic, NULL, false, act_idx);765 bfq_release_process_ref(bfqd, async_bfqq);766 }767 768 if (sync_bfqq)769 bfq_sync_bfqq_move(bfqd, sync_bfqq, bic, bfqg, act_idx);770 }771}772 773void bfq_bic_update_cgroup(struct bfq_io_cq *bic, struct bio *bio)774{775 struct bfq_data *bfqd = bic_to_bfqd(bic);776 struct bfq_group *bfqg = bfq_bio_bfqg(bfqd, bio);777 uint64_t serial_nr;778 779 serial_nr = bfqg_to_blkg(bfqg)->blkcg->css.serial_nr;780 781 /*782 * Check whether blkcg has changed. The condition may trigger783 * spuriously on a newly created cic but there's no harm.784 */785 if (unlikely(!bfqd) || likely(bic->blkcg_serial_nr == serial_nr))786 return;787 788 /*789 * New cgroup for this process. Make sure it is linked to bfq internal790 * cgroup hierarchy.791 */792 bfq_link_bfqg(bfqd, bfqg);793 __bfq_bic_change_cgroup(bfqd, bic, bfqg);794 bic->blkcg_serial_nr = serial_nr;795}796 797/**798 * bfq_flush_idle_tree - deactivate any entity on the idle tree of @st.799 * @st: the service tree being flushed.800 */801static void bfq_flush_idle_tree(struct bfq_service_tree *st)802{803 struct bfq_entity *entity = st->first_idle;804 805 for (; entity ; entity = st->first_idle)806 __bfq_deactivate_entity(entity, false);807}808 809/**810 * bfq_reparent_leaf_entity - move leaf entity to the root_group.811 * @bfqd: the device data structure with the root group.812 * @entity: the entity to move, if entity is a leaf; or the parent entity813 * of an active leaf entity to move, if entity is not a leaf.814 * @ioprio_class: I/O priority class to reparent.815 */816static void bfq_reparent_leaf_entity(struct bfq_data *bfqd,817 struct bfq_entity *entity,818 int ioprio_class)819{820 struct bfq_queue *bfqq;821 struct bfq_entity *child_entity = entity;822 823 while (child_entity->my_sched_data) { /* leaf not reached yet */824 struct bfq_sched_data *child_sd = child_entity->my_sched_data;825 struct bfq_service_tree *child_st = child_sd->service_tree +826 ioprio_class;827 struct rb_root *child_active = &child_st->active;828 829 child_entity = bfq_entity_of(rb_first(child_active));830 831 if (!child_entity)832 child_entity = child_sd->in_service_entity;833 }834 835 bfqq = bfq_entity_to_bfqq(child_entity);836 bfq_bfqq_move(bfqd, bfqq, bfqd->root_group);837}838 839/**840 * bfq_reparent_active_queues - move to the root group all active queues.841 * @bfqd: the device data structure with the root group.842 * @bfqg: the group to move from.843 * @st: the service tree to start the search from.844 * @ioprio_class: I/O priority class to reparent.845 */846static void bfq_reparent_active_queues(struct bfq_data *bfqd,847 struct bfq_group *bfqg,848 struct bfq_service_tree *st,849 int ioprio_class)850{851 struct rb_root *active = &st->active;852 struct bfq_entity *entity;853 854 while ((entity = bfq_entity_of(rb_first(active))))855 bfq_reparent_leaf_entity(bfqd, entity, ioprio_class);856 857 if (bfqg->sched_data.in_service_entity)858 bfq_reparent_leaf_entity(bfqd,859 bfqg->sched_data.in_service_entity,860 ioprio_class);861}862 863/**864 * bfq_pd_offline - deactivate the entity associated with @pd,865 * and reparent its children entities.866 * @pd: descriptor of the policy going offline.867 *868 * blkio already grabs the queue_lock for us, so no need to use869 * RCU-based magic870 */871static void bfq_pd_offline(struct blkg_policy_data *pd)872{873 struct bfq_service_tree *st;874 struct bfq_group *bfqg = pd_to_bfqg(pd);875 struct bfq_data *bfqd = bfqg->bfqd;876 struct bfq_entity *entity = bfqg->my_entity;877 unsigned long flags;878 int i;879 880 spin_lock_irqsave(&bfqd->lock, flags);881 882 if (!entity) /* root group */883 goto put_async_queues;884 885 /*886 * Empty all service_trees belonging to this group before887 * deactivating the group itself.888 */889 for (i = 0; i < BFQ_IOPRIO_CLASSES; i++) {890 st = bfqg->sched_data.service_tree + i;891 892 /*893 * It may happen that some queues are still active894 * (busy) upon group destruction (if the corresponding895 * processes have been forced to terminate). We move896 * all the leaf entities corresponding to these queues897 * to the root_group.898 * Also, it may happen that the group has an entity899 * in service, which is disconnected from the active900 * tree: it must be moved, too.901 * There is no need to put the sync queues, as the902 * scheduler has taken no reference.903 */904 bfq_reparent_active_queues(bfqd, bfqg, st, i);905 906 /*907 * The idle tree may still contain bfq_queues908 * belonging to exited task because they never909 * migrated to a different cgroup from the one being910 * destroyed now. In addition, even911 * bfq_reparent_active_queues() may happen to add some912 * entities to the idle tree. It happens if, in some913 * of the calls to bfq_bfqq_move() performed by914 * bfq_reparent_active_queues(), the queue to move is915 * empty and gets expired.916 */917 bfq_flush_idle_tree(st);918 }919 920 __bfq_deactivate_entity(entity, false);921 922put_async_queues:923 bfq_put_async_queues(bfqd, bfqg);924 925 spin_unlock_irqrestore(&bfqd->lock, flags);926 /*927 * @blkg is going offline and will be ignored by928 * blkg_[rw]stat_recursive_sum(). Transfer stats to the parent so929 * that they don't get lost. If IOs complete after this point, the930 * stats for them will be lost. Oh well...931 */932 bfqg_stats_xfer_dead(bfqg);933}934 935void bfq_end_wr_async(struct bfq_data *bfqd)936{937 struct blkcg_gq *blkg;938 939 list_for_each_entry(blkg, &bfqd->queue->blkg_list, q_node) {940 struct bfq_group *bfqg = blkg_to_bfqg(blkg);941 942 bfq_end_wr_async_queues(bfqd, bfqg);943 }944 bfq_end_wr_async_queues(bfqd, bfqd->root_group);945}946 947static int bfq_io_show_weight_legacy(struct seq_file *sf, void *v)948{949 struct blkcg *blkcg = css_to_blkcg(seq_css(sf));950 struct bfq_group_data *bfqgd = blkcg_to_bfqgd(blkcg);951 unsigned int val = 0;952 953 if (bfqgd)954 val = bfqgd->weight;955 956 seq_printf(sf, "%u\n", val);957 958 return 0;959}960 961static u64 bfqg_prfill_weight_device(struct seq_file *sf,962 struct blkg_policy_data *pd, int off)963{964 struct bfq_group *bfqg = pd_to_bfqg(pd);965 966 if (!bfqg->entity.dev_weight)967 return 0;968 return __blkg_prfill_u64(sf, pd, bfqg->entity.dev_weight);969}970 971static int bfq_io_show_weight(struct seq_file *sf, void *v)972{973 struct blkcg *blkcg = css_to_blkcg(seq_css(sf));974 struct bfq_group_data *bfqgd = blkcg_to_bfqgd(blkcg);975 976 seq_printf(sf, "default %u\n", bfqgd->weight);977 blkcg_print_blkgs(sf, blkcg, bfqg_prfill_weight_device,978 &blkcg_policy_bfq, 0, false);979 return 0;980}981 982static void bfq_group_set_weight(struct bfq_group *bfqg, u64 weight, u64 dev_weight)983{984 weight = dev_weight ?: weight;985 986 bfqg->entity.dev_weight = dev_weight;987 /*988 * Setting the prio_changed flag of the entity989 * to 1 with new_weight == weight would re-set990 * the value of the weight to its ioprio mapping.991 * Set the flag only if necessary.992 */993 if ((unsigned short)weight != bfqg->entity.new_weight) {994 bfqg->entity.new_weight = (unsigned short)weight;995 /*996 * Make sure that the above new value has been997 * stored in bfqg->entity.new_weight before998 * setting the prio_changed flag. In fact,999 * this flag may be read asynchronously (in1000 * critical sections protected by a different1001 * lock than that held here), and finding this1002 * flag set may cause the execution of the code1003 * for updating parameters whose value may1004 * depend also on bfqg->entity.new_weight (in1005 * __bfq_entity_update_weight_prio).1006 * This barrier makes sure that the new value1007 * of bfqg->entity.new_weight is correctly1008 * seen in that code.1009 */1010 smp_wmb();1011 bfqg->entity.prio_changed = 1;1012 }1013}1014 1015static int bfq_io_set_weight_legacy(struct cgroup_subsys_state *css,1016 struct cftype *cftype,1017 u64 val)1018{1019 struct blkcg *blkcg = css_to_blkcg(css);1020 struct bfq_group_data *bfqgd = blkcg_to_bfqgd(blkcg);1021 struct blkcg_gq *blkg;1022 int ret = -ERANGE;1023 1024 if (val < BFQ_MIN_WEIGHT || val > BFQ_MAX_WEIGHT)1025 return ret;1026 1027 ret = 0;1028 spin_lock_irq(&blkcg->lock);1029 bfqgd->weight = (unsigned short)val;1030 hlist_for_each_entry(blkg, &blkcg->blkg_list, blkcg_node) {1031 struct bfq_group *bfqg = blkg_to_bfqg(blkg);1032 1033 if (bfqg)1034 bfq_group_set_weight(bfqg, val, 0);1035 }1036 spin_unlock_irq(&blkcg->lock);1037 1038 return ret;1039}1040 1041static ssize_t bfq_io_set_device_weight(struct kernfs_open_file *of,1042 char *buf, size_t nbytes,1043 loff_t off)1044{1045 int ret;1046 struct blkg_conf_ctx ctx;1047 struct blkcg *blkcg = css_to_blkcg(of_css(of));1048 struct bfq_group *bfqg;1049 u64 v;1050 1051 blkg_conf_init(&ctx, buf);1052 1053 ret = blkg_conf_prep(blkcg, &blkcg_policy_bfq, &ctx);1054 if (ret)1055 goto out;1056 1057 if (sscanf(ctx.body, "%llu", &v) == 1) {1058 /* require "default" on dfl */1059 ret = -ERANGE;1060 if (!v)1061 goto out;1062 } else if (!strcmp(strim(ctx.body), "default")) {1063 v = 0;1064 } else {1065 ret = -EINVAL;1066 goto out;1067 }1068 1069 bfqg = blkg_to_bfqg(ctx.blkg);1070 1071 ret = -ERANGE;1072 if (!v || (v >= BFQ_MIN_WEIGHT && v <= BFQ_MAX_WEIGHT)) {1073 bfq_group_set_weight(bfqg, bfqg->entity.weight, v);1074 ret = 0;1075 }1076out:1077 blkg_conf_exit(&ctx);1078 return ret ?: nbytes;1079}1080 1081static ssize_t bfq_io_set_weight(struct kernfs_open_file *of,1082 char *buf, size_t nbytes,1083 loff_t off)1084{1085 char *endp;1086 int ret;1087 u64 v;1088 1089 buf = strim(buf);1090 1091 /* "WEIGHT" or "default WEIGHT" sets the default weight */1092 v = simple_strtoull(buf, &endp, 0);1093 if (*endp == '\0' || sscanf(buf, "default %llu", &v) == 1) {1094 ret = bfq_io_set_weight_legacy(of_css(of), NULL, v);1095 return ret ?: nbytes;1096 }1097 1098 return bfq_io_set_device_weight(of, buf, nbytes, off);1099}1100 1101static int bfqg_print_rwstat(struct seq_file *sf, void *v)1102{1103 blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), blkg_prfill_rwstat,1104 &blkcg_policy_bfq, seq_cft(sf)->private, true);1105 return 0;1106}1107 1108static u64 bfqg_prfill_rwstat_recursive(struct seq_file *sf,1109 struct blkg_policy_data *pd, int off)1110{1111 struct blkg_rwstat_sample sum;1112 1113 blkg_rwstat_recursive_sum(pd_to_blkg(pd), &blkcg_policy_bfq, off, &sum);1114 return __blkg_prfill_rwstat(sf, pd, &sum);1115}1116 1117static int bfqg_print_rwstat_recursive(struct seq_file *sf, void *v)1118{1119 blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)),1120 bfqg_prfill_rwstat_recursive, &blkcg_policy_bfq,1121 seq_cft(sf)->private, true);1122 return 0;1123}1124 1125#ifdef CONFIG_BFQ_CGROUP_DEBUG1126static int bfqg_print_stat(struct seq_file *sf, void *v)1127{1128 blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), blkg_prfill_stat,1129 &blkcg_policy_bfq, seq_cft(sf)->private, false);1130 return 0;1131}1132 1133static u64 bfqg_prfill_stat_recursive(struct seq_file *sf,1134 struct blkg_policy_data *pd, int off)1135{1136 struct blkcg_gq *blkg = pd_to_blkg(pd);1137 struct blkcg_gq *pos_blkg;1138 struct cgroup_subsys_state *pos_css;1139 u64 sum = 0;1140 1141 lockdep_assert_held(&blkg->q->queue_lock);1142 1143 rcu_read_lock();1144 blkg_for_each_descendant_pre(pos_blkg, pos_css, blkg) {1145 struct bfq_stat *stat;1146 1147 if (!pos_blkg->online)1148 continue;1149 1150 stat = (void *)blkg_to_pd(pos_blkg, &blkcg_policy_bfq) + off;1151 sum += bfq_stat_read(stat) + atomic64_read(&stat->aux_cnt);1152 }1153 rcu_read_unlock();1154 1155 return __blkg_prfill_u64(sf, pd, sum);1156}1157 1158static int bfqg_print_stat_recursive(struct seq_file *sf, void *v)1159{1160 blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)),1161 bfqg_prfill_stat_recursive, &blkcg_policy_bfq,1162 seq_cft(sf)->private, false);1163 return 0;1164}1165 1166static u64 bfqg_prfill_sectors(struct seq_file *sf, struct blkg_policy_data *pd,1167 int off)1168{1169 struct bfq_group *bfqg = blkg_to_bfqg(pd->blkg);1170 u64 sum = blkg_rwstat_total(&bfqg->stats.bytes);1171 1172 return __blkg_prfill_u64(sf, pd, sum >> 9);1173}1174 1175static int bfqg_print_stat_sectors(struct seq_file *sf, void *v)1176{1177 blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)),1178 bfqg_prfill_sectors, &blkcg_policy_bfq, 0, false);1179 return 0;1180}1181 1182static u64 bfqg_prfill_sectors_recursive(struct seq_file *sf,1183 struct blkg_policy_data *pd, int off)1184{1185 struct blkg_rwstat_sample tmp;1186 1187 blkg_rwstat_recursive_sum(pd->blkg, &blkcg_policy_bfq,1188 offsetof(struct bfq_group, stats.bytes), &tmp);1189 1190 return __blkg_prfill_u64(sf, pd,1191 (tmp.cnt[BLKG_RWSTAT_READ] + tmp.cnt[BLKG_RWSTAT_WRITE]) >> 9);1192}1193 1194static int bfqg_print_stat_sectors_recursive(struct seq_file *sf, void *v)1195{1196 blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)),1197 bfqg_prfill_sectors_recursive, &blkcg_policy_bfq, 0,1198 false);1199 return 0;1200}1201 1202static u64 bfqg_prfill_avg_queue_size(struct seq_file *sf,1203 struct blkg_policy_data *pd, int off)1204{1205 struct bfq_group *bfqg = pd_to_bfqg(pd);1206 u64 samples = bfq_stat_read(&bfqg->stats.avg_queue_size_samples);1207 u64 v = 0;1208 1209 if (samples) {1210 v = bfq_stat_read(&bfqg->stats.avg_queue_size_sum);1211 v = div64_u64(v, samples);1212 }1213 __blkg_prfill_u64(sf, pd, v);1214 return 0;1215}1216 1217/* print avg_queue_size */1218static int bfqg_print_avg_queue_size(struct seq_file *sf, void *v)1219{1220 blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)),1221 bfqg_prfill_avg_queue_size, &blkcg_policy_bfq,1222 0, false);1223 return 0;1224}1225#endif /* CONFIG_BFQ_CGROUP_DEBUG */1226 1227struct bfq_group *bfq_create_group_hierarchy(struct bfq_data *bfqd, int node)1228{1229 int ret;1230 1231 ret = blkcg_activate_policy(bfqd->queue->disk, &blkcg_policy_bfq);1232 if (ret)1233 return NULL;1234 1235 return blkg_to_bfqg(bfqd->queue->root_blkg);1236}1237 1238struct blkcg_policy blkcg_policy_bfq = {1239 .dfl_cftypes = bfq_blkg_files,1240 .legacy_cftypes = bfq_blkcg_legacy_files,1241 1242 .cpd_alloc_fn = bfq_cpd_alloc,1243 .cpd_free_fn = bfq_cpd_free,1244 1245 .pd_alloc_fn = bfq_pd_alloc,1246 .pd_init_fn = bfq_pd_init,1247 .pd_offline_fn = bfq_pd_offline,1248 .pd_free_fn = bfq_pd_free,1249 .pd_reset_stats_fn = bfq_pd_reset_stats,1250};1251 1252struct cftype bfq_blkcg_legacy_files[] = {1253 {1254 .name = "bfq.weight",1255 .flags = CFTYPE_NOT_ON_ROOT,1256 .seq_show = bfq_io_show_weight_legacy,1257 .write_u64 = bfq_io_set_weight_legacy,1258 },1259 {1260 .name = "bfq.weight_device",1261 .flags = CFTYPE_NOT_ON_ROOT,1262 .seq_show = bfq_io_show_weight,1263 .write = bfq_io_set_weight,1264 },1265 1266 /* statistics, covers only the tasks in the bfqg */1267 {1268 .name = "bfq.io_service_bytes",1269 .private = offsetof(struct bfq_group, stats.bytes),1270 .seq_show = bfqg_print_rwstat,1271 },1272 {1273 .name = "bfq.io_serviced",1274 .private = offsetof(struct bfq_group, stats.ios),1275 .seq_show = bfqg_print_rwstat,1276 },1277#ifdef CONFIG_BFQ_CGROUP_DEBUG1278 {1279 .name = "bfq.time",1280 .private = offsetof(struct bfq_group, stats.time),1281 .seq_show = bfqg_print_stat,1282 },1283 {1284 .name = "bfq.sectors",1285 .seq_show = bfqg_print_stat_sectors,1286 },1287 {1288 .name = "bfq.io_service_time",1289 .private = offsetof(struct bfq_group, stats.service_time),1290 .seq_show = bfqg_print_rwstat,1291 },1292 {1293 .name = "bfq.io_wait_time",1294 .private = offsetof(struct bfq_group, stats.wait_time),1295 .seq_show = bfqg_print_rwstat,1296 },1297 {1298 .name = "bfq.io_merged",1299 .private = offsetof(struct bfq_group, stats.merged),1300 .seq_show = bfqg_print_rwstat,1301 },1302 {1303 .name = "bfq.io_queued",1304 .private = offsetof(struct bfq_group, stats.queued),1305 .seq_show = bfqg_print_rwstat,1306 },1307#endif /* CONFIG_BFQ_CGROUP_DEBUG */1308 1309 /* the same statistics which cover the bfqg and its descendants */1310 {1311 .name = "bfq.io_service_bytes_recursive",1312 .private = offsetof(struct bfq_group, stats.bytes),1313 .seq_show = bfqg_print_rwstat_recursive,1314 },1315 {1316 .name = "bfq.io_serviced_recursive",1317 .private = offsetof(struct bfq_group, stats.ios),1318 .seq_show = bfqg_print_rwstat_recursive,1319 },1320#ifdef CONFIG_BFQ_CGROUP_DEBUG1321 {1322 .name = "bfq.time_recursive",1323 .private = offsetof(struct bfq_group, stats.time),1324 .seq_show = bfqg_print_stat_recursive,1325 },1326 {1327 .name = "bfq.sectors_recursive",1328 .seq_show = bfqg_print_stat_sectors_recursive,1329 },1330 {1331 .name = "bfq.io_service_time_recursive",1332 .private = offsetof(struct bfq_group, stats.service_time),1333 .seq_show = bfqg_print_rwstat_recursive,1334 },1335 {1336 .name = "bfq.io_wait_time_recursive",1337 .private = offsetof(struct bfq_group, stats.wait_time),1338 .seq_show = bfqg_print_rwstat_recursive,1339 },1340 {1341 .name = "bfq.io_merged_recursive",1342 .private = offsetof(struct bfq_group, stats.merged),1343 .seq_show = bfqg_print_rwstat_recursive,1344 },1345 {1346 .name = "bfq.io_queued_recursive",1347 .private = offsetof(struct bfq_group, stats.queued),1348 .seq_show = bfqg_print_rwstat_recursive,1349 },1350 {1351 .name = "bfq.avg_queue_size",1352 .seq_show = bfqg_print_avg_queue_size,1353 },1354 {1355 .name = "bfq.group_wait_time",1356 .private = offsetof(struct bfq_group, stats.group_wait_time),1357 .seq_show = bfqg_print_stat,1358 },1359 {1360 .name = "bfq.idle_time",1361 .private = offsetof(struct bfq_group, stats.idle_time),1362 .seq_show = bfqg_print_stat,1363 },1364 {1365 .name = "bfq.empty_time",1366 .private = offsetof(struct bfq_group, stats.empty_time),1367 .seq_show = bfqg_print_stat,1368 },1369 {1370 .name = "bfq.dequeue",1371 .private = offsetof(struct bfq_group, stats.dequeue),1372 .seq_show = bfqg_print_stat,1373 },1374#endif /* CONFIG_BFQ_CGROUP_DEBUG */1375 { } /* terminate */1376};1377 1378struct cftype bfq_blkg_files[] = {1379 {1380 .name = "bfq.weight",1381 .flags = CFTYPE_NOT_ON_ROOT,1382 .seq_show = bfq_io_show_weight,1383 .write = bfq_io_set_weight,1384 },1385 {} /* terminate */1386};1387 1388#else /* CONFIG_BFQ_GROUP_IOSCHED */1389 1390void bfq_bfqq_move(struct bfq_data *bfqd, struct bfq_queue *bfqq,1391 struct bfq_group *bfqg) {}1392 1393void bfq_init_entity(struct bfq_entity *entity, struct bfq_group *bfqg)1394{1395 struct bfq_queue *bfqq = bfq_entity_to_bfqq(entity);1396 1397 entity->weight = entity->new_weight;1398 entity->orig_weight = entity->new_weight;1399 if (bfqq) {1400 bfqq->ioprio = bfqq->new_ioprio;1401 bfqq->ioprio_class = bfqq->new_ioprio_class;1402 }1403 entity->sched_data = &bfqg->sched_data;1404}1405 1406void bfq_bic_update_cgroup(struct bfq_io_cq *bic, struct bio *bio) {}1407 1408void bfq_end_wr_async(struct bfq_data *bfqd)1409{1410 bfq_end_wr_async_queues(bfqd, bfqd->root_group);1411}1412 1413struct bfq_group *bfq_bio_bfqg(struct bfq_data *bfqd, struct bio *bio)1414{1415 return bfqd->root_group;1416}1417 1418struct bfq_group *bfqq_group(struct bfq_queue *bfqq)1419{1420 return bfqq->bfqd->root_group;1421}1422 1423void bfqg_and_blkg_put(struct bfq_group *bfqg) {}1424 1425struct bfq_group *bfq_create_group_hierarchy(struct bfq_data *bfqd, int node)1426{1427 struct bfq_group *bfqg;1428 int i;1429 1430 bfqg = kmalloc_node(sizeof(*bfqg), GFP_KERNEL | __GFP_ZERO, node);1431 if (!bfqg)1432 return NULL;1433 1434 for (i = 0; i < BFQ_IOPRIO_CLASSES; i++)1435 bfqg->sched_data.service_tree[i] = BFQ_SERVICE_TREE_INIT;1436 1437 return bfqg;1438}1439#endif /* CONFIG_BFQ_GROUP_IOSCHED */1440