diff options
Diffstat (limited to 'block/bfq-wf2q.c')
| -rw-r--r-- | block/bfq-wf2q.c | 60 |
1 files changed, 35 insertions, 25 deletions
diff --git a/block/bfq-wf2q.c b/block/bfq-wf2q.c index 72adbbe975d5..c9ba225081ce 100644 --- a/block/bfq-wf2q.c +++ b/block/bfq-wf2q.c @@ -1,19 +1,10 @@ +// SPDX-License-Identifier: GPL-2.0-or-later /* * Hierarchical Budget Worst-case Fair Weighted Fair Queueing * (B-WF2Q+): hierarchical scheduling algorithm by which the BFQ I/O * scheduler schedules generic entities. The latter can represent * either single bfq queues (associated with processes) or groups of * bfq queues (associated with cgroups). - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License as - * published by the Free Software Foundation; either version 2 of the - * License, or (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * General Public License for more details. */ #include "bfq-iosched.h" @@ -44,6 +35,12 @@ static unsigned int bfq_class_idx(struct bfq_entity *entity) BFQ_DEFAULT_GRP_CLASS - 1; } +unsigned int bfq_tot_busy_queues(struct bfq_data *bfqd) +{ + return bfqd->busy_queues[0] + bfqd->busy_queues[1] + + bfqd->busy_queues[2]; +} + static struct bfq_entity *bfq_lookup_next_entity(struct bfq_sched_data *sd, bool expiration); @@ -53,7 +50,7 @@ static bool bfq_update_parent_budget(struct bfq_entity *next_in_service); * bfq_update_next_in_service - update sd->next_in_service * @sd: sched_data for which to perform the update. * @new_entity: if not NULL, pointer to the entity whose activation, - * requeueing or repositionig triggered the invocation of + * requeueing or repositioning triggered the invocation of * this function. * @expiration: id true, this function is being invoked after the * expiration of the in-service entity @@ -84,7 +81,7 @@ static bool bfq_update_next_in_service(struct bfq_sched_data *sd, /* * If this update is triggered by the activation, requeueing - * or repositiong of an entity that does not coincide with + * or repositioning of an entity that does not coincide with * sd->next_in_service, then a full lookup in the active tree * can be avoided. In fact, it is enough to check whether the * just-modified entity has the same priority as @@ -731,7 +728,7 @@ __bfq_entity_update_weight_prio(struct bfq_service_tree *old_st, struct bfq_queue *bfqq = bfq_entity_to_bfqq(entity); unsigned int prev_weight, new_weight; struct bfq_data *bfqd = NULL; - struct rb_root *root; + struct rb_root_cached *root; #ifdef CONFIG_BFQ_GROUP_IOSCHED struct bfq_sched_data *sd; struct bfq_group *bfqg; @@ -1006,7 +1003,7 @@ static void __bfq_activate_entity(struct bfq_entity *entity, entity->on_st = true; } -#ifdef BFQ_GROUP_IOSCHED_ENABLED +#ifdef CONFIG_BFQ_GROUP_IOSCHED if (!bfq_entity_to_bfqq(entity)) { /* bfq_group */ struct bfq_group *bfqg = container_of(entity, struct bfq_group, entity); @@ -1390,7 +1387,7 @@ left: * In this first case, update the virtual time in @st too (see the * comments on this update inside the function). * - * In constrast, if there is an in-service entity, then return the + * In contrast, if there is an in-service entity, then return the * entity that would be set in service if not only the above * conditions, but also the next one held true: the currently * in-service entity, on expiration, @@ -1473,12 +1470,12 @@ static struct bfq_entity *bfq_lookup_next_entity(struct bfq_sched_data *sd, * is being invoked as a part of the expiration path * of the in-service queue. In this case, even if * sd->in_service_entity is not NULL, - * sd->in_service_entiy at this point is actually not + * sd->in_service_entity at this point is actually not * in service any more, and, if needed, has already * been properly queued or requeued into the right * tree. The reason why sd->in_service_entity is still * not NULL here, even if expiration is true, is that - * sd->in_service_entiy is reset as a last step in the + * sd->in_service_entity is reset as a last step in the * expiration path. So, if expiration is true, tell * __bfq_lookup_next_entity that there is no * sd->in_service_entity. @@ -1513,7 +1510,7 @@ struct bfq_queue *bfq_get_next_queue(struct bfq_data *bfqd) struct bfq_sched_data *sd; struct bfq_queue *bfqq; - if (bfqd->busy_queues == 0) + if (bfq_tot_busy_queues(bfqd) == 0) return NULL; /* @@ -1599,7 +1596,8 @@ struct bfq_queue *bfq_get_next_queue(struct bfq_data *bfqd) return bfqq; } -void __bfq_bfqd_reset_in_service(struct bfq_data *bfqd) +/* returns true if the in-service queue gets freed */ +bool __bfq_bfqd_reset_in_service(struct bfq_data *bfqd) { struct bfq_queue *in_serv_bfqq = bfqd->in_service_queue; struct bfq_entity *in_serv_entity = &in_serv_bfqq->entity; @@ -1623,8 +1621,20 @@ void __bfq_bfqd_reset_in_service(struct bfq_data *bfqd) * service tree either, then release the service reference to * the queue it represents (taken with bfq_get_entity). */ - if (!in_serv_entity->on_st) + if (!in_serv_entity->on_st) { + /* + * If no process is referencing in_serv_bfqq any + * longer, then the service reference may be the only + * reference to the queue. If this is the case, then + * bfqq gets freed here. + */ + int ref = in_serv_bfqq->ref; bfq_put_queue(in_serv_bfqq); + if (ref == 1) + return true; + } + + return false; } void bfq_deactivate_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq, @@ -1665,10 +1675,7 @@ void bfq_del_bfqq_busy(struct bfq_data *bfqd, struct bfq_queue *bfqq, bfq_clear_bfqq_busy(bfqq); - bfqd->busy_queues--; - - if (!bfqq->dispatched) - bfq_weights_tree_remove(bfqd, bfqq); + bfqd->busy_queues[bfqq->ioprio_class - 1]--; if (bfqq->wr_coeff > 1) bfqd->wr_busy_queues--; @@ -1676,6 +1683,9 @@ void bfq_del_bfqq_busy(struct bfq_data *bfqd, struct bfq_queue *bfqq, bfqg_stats_update_dequeue(bfqq_group(bfqq)); bfq_deactivate_bfqq(bfqd, bfqq, true, expiration); + + if (!bfqq->dispatched) + bfq_weights_tree_remove(bfqd, bfqq); } /* @@ -1688,7 +1698,7 @@ void bfq_add_bfqq_busy(struct bfq_data *bfqd, struct bfq_queue *bfqq) bfq_activate_bfqq(bfqd, bfqq); bfq_mark_bfqq_busy(bfqq); - bfqd->busy_queues++; + bfqd->busy_queues[bfqq->ioprio_class - 1]++; if (!bfqq->dispatched) if (bfqq->wr_coeff == 1) |