From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:51960 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751061AbdHZQfd (ORCPT ); Sat, 26 Aug 2017 12:35:33 -0400 From: Ming Lei To: Jens Axboe , linux-block@vger.kernel.org, Christoph Hellwig Cc: Bart Van Assche , Laurence Oberman , Paolo Valente , Mel Gorman , Ming Lei Subject: [PATCH V3 12/14] block: introduce .last_merge and .hash to blk_mq_ctx Date: Sun, 27 Aug 2017 00:33:30 +0800 Message-Id: <20170826163332.28971-13-ming.lei@redhat.com> In-Reply-To: <20170826163332.28971-1-ming.lei@redhat.com> References: <20170826163332.28971-1-ming.lei@redhat.com> Sender: linux-block-owner@vger.kernel.org List-Id: linux-block@vger.kernel.org Prepare for supporting bio merge to sw queue if no blk-mq io scheduler is taken. Signed-off-by: Ming Lei --- block/blk-mq.h | 4 ++++ block/blk.h | 3 +++ block/elevator.c | 22 +++++++++++++++++++--- 3 files changed, 26 insertions(+), 3 deletions(-) diff --git a/block/blk-mq.h b/block/blk-mq.h index 0277f9771fab..1b9742eb7399 100644 --- a/block/blk-mq.h +++ b/block/blk-mq.h @@ -18,6 +18,10 @@ struct blk_mq_ctx { unsigned long rq_dispatched[2]; unsigned long rq_merged; + /* bio merge via request hash table */ + struct request *last_merge; + DECLARE_HASHTABLE(hash, ELV_HASH_BITS); + /* incremented at completion time */ unsigned long ____cacheline_aligned_in_smp rq_completed[2]; diff --git a/block/blk.h b/block/blk.h index 313002c2f666..6847c5435cca 100644 --- a/block/blk.h +++ b/block/blk.h @@ -199,6 +199,9 @@ static inline struct request *rqhash_find(struct hlist_head *hash, sector_t offs return NULL; } +enum elv_merge elv_merge_ctx(struct request_queue *q, struct request **req, + struct bio *bio, struct blk_mq_ctx *ctx); + void blk_insert_flush(struct request *rq); static inline struct request *__elv_next_request(struct request_queue *q) diff --git a/block/elevator.c b/block/elevator.c index a4e35419cf9a..0e465809d3f3 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -471,6 +471,13 @@ enum elv_merge elv_merge(struct request_queue *q, struct request **req, return __elv_merge(q, req, bio, q->elevator->hash, q->last_merge); } +enum elv_merge elv_merge_ctx(struct request_queue *q, struct request **req, + struct bio *bio, struct blk_mq_ctx *ctx) +{ + WARN_ON_ONCE(!q->mq_ops); + return __elv_merge(q, req, bio, ctx->hash, ctx->last_merge); +} + /* * Attempt to do an insertion back merge. Only check for the case where * we can append 'rq' to an existing request, so we can throw 'rq' away @@ -516,16 +523,25 @@ void elv_merged_request(struct request_queue *q, struct request *rq, enum elv_merge type) { struct elevator_queue *e = q->elevator; + struct hlist_head *hash = e->hash; + + /* we do bio merge on blk-mq sw queue */ + if (q->mq_ops && !e) { + rq->mq_ctx->last_merge = rq; + hash = rq->mq_ctx->hash; + goto reposition; + } + + q->last_merge = rq; if (e->uses_mq && e->type->ops.mq.request_merged) e->type->ops.mq.request_merged(q, rq, type); else if (!e->uses_mq && e->type->ops.sq.elevator_merged_fn) e->type->ops.sq.elevator_merged_fn(q, rq, type); + reposition: if (type == ELEVATOR_BACK_MERGE) - elv_rqhash_reposition(q, rq); - - q->last_merge = rq; + rqhash_reposition(hash, rq); } void elv_merge_requests(struct request_queue *q, struct request *rq, -- 2.9.5