From f794f3351f2672d782b8df0fa59f3cef38cffa59 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Fri, 8 Oct 2021 05:50:46 -0600 Subject: [PATCH] block: add support for blk_mq_end_request_batch() Instead of calling blk_mq_end_request() on a single request, add a helper that takes the new struct io_comp_batch and completes any request stored in there. Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-mq-tag.c | 6 ++++ block/blk-mq-tag.h | 1 + block/blk-mq.c | 82 ++++++++++++++++++++++++++++++++++++++------------ include/linux/blk-mq.h | 29 ++++++++++++++++++ 4 files changed, 99 insertions(+), 19 deletions(-) diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index c43b97201161..b94c3e8ef392 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -207,6 +207,12 @@ void blk_mq_put_tag(struct blk_mq_tags *tags, struct blk_mq_ctx *ctx, } } +void blk_mq_put_tags(struct blk_mq_tags *tags, int *tag_array, int nr_tags) +{ + sbitmap_queue_clear_batch(&tags->bitmap_tags, tags->nr_reserved_tags, + tag_array, nr_tags); +} + struct bt_iter_data { struct blk_mq_hw_ctx *hctx; busy_iter_fn *fn; diff --git a/block/blk-mq-tag.h b/block/blk-mq-tag.h index 71c2f7d8e9b7..78ae2fb8e2a4 100644 --- a/block/blk-mq-tag.h +++ b/block/blk-mq-tag.h @@ -42,6 +42,7 @@ unsigned long blk_mq_get_tags(struct blk_mq_alloc_data *data, int nr_tags, unsigned int *offset); extern void blk_mq_put_tag(struct blk_mq_tags *tags, struct blk_mq_ctx *ctx, unsigned int tag); +void blk_mq_put_tags(struct blk_mq_tags *tags, int *tag_array, int nr_tags); extern int blk_mq_tag_update_depth(struct blk_mq_hw_ctx *hctx, struct blk_mq_tags **tags, unsigned int depth, bool can_grow); diff --git a/block/blk-mq.c b/block/blk-mq.c index 79c25b64e8b0..9248edd8a7d3 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -300,15 +300,6 @@ void blk_mq_wake_waiters(struct request_queue *q) blk_mq_tag_wakeup_all(hctx->tags, true); } -/* - * Only need start/end time stamping if we have iostat or - * blk stats enabled, or using an IO scheduler. - */ -static inline bool blk_mq_need_time_stamp(struct request *rq) -{ - return (rq->rq_flags & (RQF_IO_STAT | RQF_STATS | RQF_ELV)); -} - static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data, unsigned int tag, u64 alloc_time_ns) { @@ -768,19 +759,21 @@ bool blk_update_request(struct request *req, blk_status_t error, } EXPORT_SYMBOL_GPL(blk_update_request); -inline void __blk_mq_end_request(struct request *rq, blk_status_t error) +static inline void __blk_mq_end_request_acct(struct request *rq, u64 now) { - if (blk_mq_need_time_stamp(rq)) { - u64 now = ktime_get_ns(); + if (rq->rq_flags & RQF_STATS) { + blk_mq_poll_stats_start(rq->q); + blk_stat_add(rq, now); + } - if (rq->rq_flags & RQF_STATS) { - blk_mq_poll_stats_start(rq->q); - blk_stat_add(rq, now); - } + blk_mq_sched_completed_request(rq, now); + blk_account_io_done(rq, now); +} - blk_mq_sched_completed_request(rq, now); - blk_account_io_done(rq, now); - } +inline void __blk_mq_end_request(struct request *rq, blk_status_t error) +{ + if (blk_mq_need_time_stamp(rq)) + __blk_mq_end_request_acct(rq, ktime_get_ns()); if (rq->end_io) { rq_qos_done(rq->q, rq); @@ -799,6 +792,57 @@ void blk_mq_end_request(struct request *rq, blk_status_t error) } EXPORT_SYMBOL(blk_mq_end_request); +#define TAG_COMP_BATCH 32 + +static inline void blk_mq_flush_tag_batch(struct blk_mq_hw_ctx *hctx, + int *tag_array, int nr_tags) +{ + struct request_queue *q = hctx->queue; + + blk_mq_put_tags(hctx->tags, tag_array, nr_tags); + percpu_ref_put_many(&q->q_usage_counter, nr_tags); +} + +void blk_mq_end_request_batch(struct io_comp_batch *iob) +{ + int tags[TAG_COMP_BATCH], nr_tags = 0; + struct blk_mq_hw_ctx *last_hctx = NULL; + struct request *rq; + u64 now = 0; + + if (iob->need_ts) + now = ktime_get_ns(); + + while ((rq = rq_list_pop(&iob->req_list)) != NULL) { + prefetch(rq->bio); + prefetch(rq->rq_next); + + blk_update_request(rq, BLK_STS_OK, blk_rq_bytes(rq)); + if (iob->need_ts) + __blk_mq_end_request_acct(rq, now); + + WRITE_ONCE(rq->state, MQ_RQ_IDLE); + if (!refcount_dec_and_test(&rq->ref)) + continue; + + blk_crypto_free_request(rq); + blk_pm_mark_last_busy(rq); + rq_qos_done(rq->q, rq); + + if (nr_tags == TAG_COMP_BATCH || + (last_hctx && last_hctx != rq->mq_hctx)) { + blk_mq_flush_tag_batch(last_hctx, tags, nr_tags); + nr_tags = 0; + } + tags[nr_tags++] = rq->tag; + last_hctx = rq->mq_hctx; + } + + if (nr_tags) + blk_mq_flush_tag_batch(last_hctx, tags, nr_tags); +} +EXPORT_SYMBOL_GPL(blk_mq_end_request_batch); + static void blk_complete_reqs(struct llist_head *list) { struct llist_node *entry = llist_reverse_order(llist_del_all(list)); diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 4c79439af2f2..656fe34bdb6c 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -728,6 +728,35 @@ static inline void blk_mq_set_request_complete(struct request *rq) void blk_mq_start_request(struct request *rq); void blk_mq_end_request(struct request *rq, blk_status_t error); void __blk_mq_end_request(struct request *rq, blk_status_t error); +void blk_mq_end_request_batch(struct io_comp_batch *ib); + +/* + * Only need start/end time stamping if we have iostat or + * blk stats enabled, or using an IO scheduler. + */ +static inline bool blk_mq_need_time_stamp(struct request *rq) +{ + return (rq->rq_flags & (RQF_IO_STAT | RQF_STATS | RQF_ELV)); +} + +/* + * Batched completions only work when there is no I/O error and no special + * ->end_io handler. + */ +static inline bool blk_mq_add_to_batch(struct request *req, + struct io_comp_batch *iob, int ioerror, + void (*complete)(struct io_comp_batch *)) +{ + if (!iob || (req->rq_flags & RQF_ELV) || req->end_io || ioerror) + return false; + if (!iob->complete) + iob->complete = complete; + else if (iob->complete != complete) + return false; + iob->need_ts |= blk_mq_need_time_stamp(req); + rq_list_add(&iob->req_list, req); + return true; +} void blk_mq_requeue_request(struct request *rq, bool kick_requeue_list); void blk_mq_kick_requeue_list(struct request_queue *q); -- 2.11.0