diff options
Diffstat (limited to 'block/bfq-iosched.c')
| -rw-r--r-- | block/bfq-iosched.c | 206 |
1 files changed, 113 insertions, 93 deletions
diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c index 36a4998c4b37..0747d9d0e48c 100644 --- a/block/bfq-iosched.c +++ b/block/bfq-iosched.c @@ -2911,8 +2911,12 @@ bfq_setup_cooperator(struct bfq_data *bfqd, struct bfq_queue *bfqq, struct bfq_iocq_bfqq_data *bfqq_data = &bic->bfqq_data[a_idx]; /* if a merge has already been setup, then proceed with that first */ - if (bfqq->new_bfqq) - return bfqq->new_bfqq; + new_bfqq = bfqq->new_bfqq; + if (new_bfqq) { + while (new_bfqq->new_bfqq) + new_bfqq = new_bfqq->new_bfqq; + return new_bfqq; + } /* * Check delayed stable merge for rotational or non-queueing @@ -3093,8 +3097,8 @@ static void bfq_bfqq_save_state(struct bfq_queue *bfqq) } -static void -bfq_reassign_last_bfqq(struct bfq_queue *cur_bfqq, struct bfq_queue *new_bfqq) +void bfq_reassign_last_bfqq(struct bfq_queue *cur_bfqq, + struct bfq_queue *new_bfqq) { if (cur_bfqq->entity.parent && cur_bfqq->entity.parent->last_bfqq_created == cur_bfqq) @@ -3125,10 +3129,12 @@ void bfq_release_process_ref(struct bfq_data *bfqd, struct bfq_queue *bfqq) bfq_put_queue(bfqq); } -static void -bfq_merge_bfqqs(struct bfq_data *bfqd, struct bfq_io_cq *bic, - struct bfq_queue *bfqq, struct bfq_queue *new_bfqq) +static struct bfq_queue *bfq_merge_bfqqs(struct bfq_data *bfqd, + struct bfq_io_cq *bic, + struct bfq_queue *bfqq) { + struct bfq_queue *new_bfqq = bfqq->new_bfqq; + bfq_log_bfqq(bfqd, bfqq, "merging with queue %lu", (unsigned long)new_bfqq->pid); /* Save weight raising and idle window of the merged queues */ @@ -3222,6 +3228,8 @@ bfq_merge_bfqqs(struct bfq_data *bfqd, struct bfq_io_cq *bic, bfq_reassign_last_bfqq(bfqq, new_bfqq); bfq_release_process_ref(bfqd, bfqq); + + return new_bfqq; } static bool bfq_allow_bio_merge(struct request_queue *q, struct request *rq, @@ -3257,14 +3265,8 @@ static bool bfq_allow_bio_merge(struct request_queue *q, struct request *rq, * fulfilled, i.e., bic can be redirected to new_bfqq * and bfqq can be put. */ - bfq_merge_bfqqs(bfqd, bfqd->bio_bic, bfqq, - new_bfqq); - /* - * If we get here, bio will be queued into new_queue, - * so use new_bfqq to decide whether bio and rq can be - * merged. - */ - bfqq = new_bfqq; + while (bfqq != new_bfqq) + bfqq = bfq_merge_bfqqs(bfqd, bfqd->bio_bic, bfqq); /* * Change also bqfd->bio_bfqq, as @@ -5432,6 +5434,8 @@ void bfq_put_cooperator(struct bfq_queue *bfqq) bfq_put_queue(__bfqq); __bfqq = next; } + + bfq_release_process_ref(bfqq->bfqd, bfqq); } static void bfq_exit_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq) @@ -5444,8 +5448,6 @@ static void bfq_exit_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq) bfq_log_bfqq(bfqd, bfqq, "exit_bfqq: %p, %d", bfqq, bfqq->ref); bfq_put_cooperator(bfqq); - - bfq_release_process_ref(bfqd, bfqq); } static void bfq_exit_icq_bfqq(struct bfq_io_cq *bic, bool is_sync, @@ -5701,9 +5703,7 @@ bfq_do_early_stable_merge(struct bfq_data *bfqd, struct bfq_queue *bfqq, * state before killing it. */ bfqq->bic = bic; - bfq_merge_bfqqs(bfqd, bic, bfqq, new_bfqq); - - return new_bfqq; + return bfq_merge_bfqqs(bfqd, bic, bfqq); } /* @@ -6158,6 +6158,7 @@ static bool __bfq_insert_request(struct bfq_data *bfqd, struct request *rq) bool waiting, idle_timer_disabled = false; if (new_bfqq) { + struct bfq_queue *old_bfqq = bfqq; /* * Release the request's reference to the old bfqq * and make sure one is taken to the shared queue. @@ -6174,18 +6175,18 @@ static bool __bfq_insert_request(struct bfq_data *bfqd, struct request *rq) * new_bfqq. */ if (bic_to_bfqq(RQ_BIC(rq), true, - bfq_actuator_index(bfqd, rq->bio)) == bfqq) - bfq_merge_bfqqs(bfqd, RQ_BIC(rq), - bfqq, new_bfqq); + bfq_actuator_index(bfqd, rq->bio)) == bfqq) { + while (bfqq != new_bfqq) + bfqq = bfq_merge_bfqqs(bfqd, RQ_BIC(rq), bfqq); + } - bfq_clear_bfqq_just_created(bfqq); + bfq_clear_bfqq_just_created(old_bfqq); /* * rq is about to be enqueued into new_bfqq, * release rq reference on bfqq */ - bfq_put_queue(bfqq); + bfq_put_queue(old_bfqq); rq->elv.priv[1] = new_bfqq; - bfqq = new_bfqq; } bfq_update_io_thinktime(bfqd, bfqq); @@ -6723,7 +6724,7 @@ bfq_split_bfqq(struct bfq_io_cq *bic, struct bfq_queue *bfqq) { bfq_log_bfqq(bfqq->bfqd, bfqq, "splitting queue"); - if (bfqq_process_refs(bfqq) == 1) { + if (bfqq_process_refs(bfqq) == 1 && !bfqq->new_bfqq) { bfqq->pid = current->pid; bfq_clear_bfqq_coop(bfqq); bfq_clear_bfqq_split_coop(bfqq); @@ -6733,16 +6734,13 @@ bfq_split_bfqq(struct bfq_io_cq *bic, struct bfq_queue *bfqq) bic_set_bfqq(bic, NULL, true, bfqq->actuator_idx); bfq_put_cooperator(bfqq); - - bfq_release_process_ref(bfqq->bfqd, bfqq); return NULL; } -static struct bfq_queue *bfq_get_bfqq_handle_split(struct bfq_data *bfqd, - struct bfq_io_cq *bic, - struct bio *bio, - bool split, bool is_sync, - bool *new_queue) +static struct bfq_queue * +__bfq_get_bfqq_handle_split(struct bfq_data *bfqd, struct bfq_io_cq *bic, + struct bio *bio, bool split, bool is_sync, + bool *new_queue) { unsigned int act_idx = bfq_actuator_index(bfqd, bio); struct bfq_queue *bfqq = bic_to_bfqq(bic, is_sync, act_idx); @@ -6821,6 +6819,84 @@ static void bfq_prepare_request(struct request *rq) rq->elv.priv[0] = rq->elv.priv[1] = NULL; } +static struct bfq_queue *bfq_waker_bfqq(struct bfq_queue *bfqq) +{ + struct bfq_queue *new_bfqq = bfqq->new_bfqq; + struct bfq_queue *waker_bfqq = bfqq->waker_bfqq; + + if (!waker_bfqq) + return NULL; + + while (new_bfqq) { + if (new_bfqq == waker_bfqq) { + /* + * If waker_bfqq is in the merge chain, and current + * is the only procress. + */ + if (bfqq_process_refs(waker_bfqq) == 1) + return NULL; + break; + } + + new_bfqq = new_bfqq->new_bfqq; + } + + return waker_bfqq; +} + +static struct bfq_queue *bfq_get_bfqq_handle_split(struct bfq_data *bfqd, + struct bfq_io_cq *bic, + struct bio *bio, + unsigned int idx, + bool is_sync) +{ + struct bfq_queue *waker_bfqq; + struct bfq_queue *bfqq; + bool new_queue = false; + + bfqq = __bfq_get_bfqq_handle_split(bfqd, bic, bio, false, is_sync, + &new_queue); + if (unlikely(new_queue)) + return bfqq; + + /* If the queue was seeky for too long, break it apart. */ + if (!bfq_bfqq_coop(bfqq) || !bfq_bfqq_split_coop(bfqq) || + bic->bfqq_data[idx].stably_merged) + return bfqq; + + waker_bfqq = bfq_waker_bfqq(bfqq); + + /* Update bic before losing reference to bfqq */ + if (bfq_bfqq_in_large_burst(bfqq)) + bic->bfqq_data[idx].saved_in_large_burst = true; + + bfqq = bfq_split_bfqq(bic, bfqq); + if (bfqq) { + bfq_bfqq_resume_state(bfqq, bfqd, bic, true); + return bfqq; + } + + bfqq = __bfq_get_bfqq_handle_split(bfqd, bic, bio, true, is_sync, NULL); + if (unlikely(bfqq == &bfqd->oom_bfqq)) + return bfqq; + + bfq_bfqq_resume_state(bfqq, bfqd, bic, false); + bfqq->waker_bfqq = waker_bfqq; + bfqq->tentative_waker_bfqq = NULL; + + /* + * If the waker queue disappears, then new_bfqq->waker_bfqq must be + * reset. So insert new_bfqq into the + * woken_list of the waker. See + * bfq_check_waker for details. + */ + if (waker_bfqq) + hlist_add_head(&bfqq->woken_list_node, + &bfqq->waker_bfqq->woken_list); + + return bfqq; +} + /* * If needed, init rq, allocate bfq data structures associated with * rq, and increment reference counters in the destination bfq_queue @@ -6852,8 +6928,6 @@ static struct bfq_queue *bfq_init_rq(struct request *rq) struct bfq_io_cq *bic; const int is_sync = rq_is_sync(rq); struct bfq_queue *bfqq; - bool new_queue = false; - bool bfqq_already_existing = false, split = false; unsigned int a_idx = bfq_actuator_index(bfqd, bio); if (unlikely(!rq->elv.icq)) @@ -6870,54 +6944,9 @@ static struct bfq_queue *bfq_init_rq(struct request *rq) return RQ_BFQQ(rq); bic = icq_to_bic(rq->elv.icq); - bfq_check_ioprio_change(bic, bio); - bfq_bic_update_cgroup(bic, bio); - - bfqq = bfq_get_bfqq_handle_split(bfqd, bic, bio, false, is_sync, - &new_queue); - - if (likely(!new_queue)) { - /* If the queue was seeky for too long, break it apart. */ - if (bfq_bfqq_coop(bfqq) && bfq_bfqq_split_coop(bfqq) && - !bic->bfqq_data[a_idx].stably_merged) { - struct bfq_queue *old_bfqq = bfqq; - - /* Update bic before losing reference to bfqq */ - if (bfq_bfqq_in_large_burst(bfqq)) - bic->bfqq_data[a_idx].saved_in_large_burst = - true; - - bfqq = bfq_split_bfqq(bic, bfqq); - split = true; - - if (!bfqq) { - bfqq = bfq_get_bfqq_handle_split(bfqd, bic, bio, - true, is_sync, - NULL); - if (unlikely(bfqq == &bfqd->oom_bfqq)) - bfqq_already_existing = true; - } else - bfqq_already_existing = true; - - if (!bfqq_already_existing) { - bfqq->waker_bfqq = old_bfqq->waker_bfqq; - bfqq->tentative_waker_bfqq = NULL; - - /* - * If the waker queue disappears, then - * new_bfqq->waker_bfqq must be - * reset. So insert new_bfqq into the - * woken_list of the waker. See - * bfq_check_waker for details. - */ - if (bfqq->waker_bfqq) - hlist_add_head(&bfqq->woken_list_node, - &bfqq->waker_bfqq->woken_list); - } - } - } + bfqq = bfq_get_bfqq_handle_split(bfqd, bic, bio, a_idx, is_sync); bfqq_request_allocated(bfqq); bfqq->ref++; @@ -6934,18 +6963,9 @@ static struct bfq_queue *bfq_init_rq(struct request *rq) * addition, if the queue has also just been split, we have to * resume its state. */ - if (likely(bfqq != &bfqd->oom_bfqq) && bfqq_process_refs(bfqq) == 1) { + if (likely(bfqq != &bfqd->oom_bfqq) && !bfqq->new_bfqq && + bfqq_process_refs(bfqq) == 1) bfqq->bic = bic; - if (split) { - /* - * The queue has just been split from a shared - * queue: restore the idle window and the - * possible weight raising period. - */ - bfq_bfqq_resume_state(bfqq, bfqd, bic, - bfqq_already_existing); - } - } /* * Consider bfqq as possibly belonging to a burst of newly |