From 14ccb66b3f585b2bc21e7256c96090abed5a512c Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 6 Jun 2019 12:29:01 +0200 Subject: block: remove the bi_phys_segments field in struct bio We only need the number of segments in the blk-mq submission path. Remove the field from struct bio, and return it from a variant of blk_queue_split instead of that it can passed as an argument to those functions that need the value. This also means we stop recounting segments except for cloning and partial segments. To keep the number of arguments in this how path down remove pointless struct request_queue arguments from any of the functions that had it and grew a nr_segs argument. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/kyber-iosched.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'block/kyber-iosched.c') diff --git a/block/kyber-iosched.c b/block/kyber-iosched.c index c3b05119cebd..3c2602601741 100644 --- a/block/kyber-iosched.c +++ b/block/kyber-iosched.c @@ -562,7 +562,8 @@ static void kyber_limit_depth(unsigned int op, struct blk_mq_alloc_data *data) } } -static bool kyber_bio_merge(struct blk_mq_hw_ctx *hctx, struct bio *bio) +static bool kyber_bio_merge(struct blk_mq_hw_ctx *hctx, struct bio *bio, + unsigned int nr_segs) { struct kyber_hctx_data *khd = hctx->sched_data; struct blk_mq_ctx *ctx = blk_mq_get_ctx(hctx->queue); @@ -572,7 +573,7 @@ static bool kyber_bio_merge(struct blk_mq_hw_ctx *hctx, struct bio *bio) bool merged; spin_lock(&kcq->lock); - merged = blk_mq_bio_list_merge(hctx->queue, rq_list, bio); + merged = blk_mq_bio_list_merge(hctx->queue, rq_list, bio, nr_segs); spin_unlock(&kcq->lock); blk_mq_put_ctx(ctx); -- cgit v1.2.3 From c05f42206f4de12b6807270fc669b45472f1bdb7 Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Mon, 1 Jul 2019 08:47:29 -0700 Subject: blk-mq: remove blk_mq_put_ctx() No code that occurs between blk_mq_get_ctx() and blk_mq_put_ctx() depends on preemption being disabled for its correctness. Since removing the CPU preemption calls does not measurably affect performance, simplify the blk-mq code by removing the blk_mq_put_ctx() function and also by not disabling preemption in blk_mq_get_ctx(). Cc: Hannes Reinecke Cc: Omar Sandoval Reviewed-by: Christoph Hellwig Reviewed-by: Ming Lei Signed-off-by: Bart Van Assche Signed-off-by: Jens Axboe --- block/blk-mq-sched.c | 5 +---- block/blk-mq-tag.c | 8 -------- block/blk-mq.c | 16 +++------------- block/blk-mq.h | 7 +------ block/kyber-iosched.c | 1 - 5 files changed, 5 insertions(+), 32 deletions(-) (limited to 'block/kyber-iosched.c') diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c index 956a7aa9a637..c9d183d6c499 100644 --- a/block/blk-mq-sched.c +++ b/block/blk-mq-sched.c @@ -330,10 +330,8 @@ bool __blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio, bool ret = false; enum hctx_type type; - if (e && e->type->ops.bio_merge) { - blk_mq_put_ctx(ctx); + if (e && e->type->ops.bio_merge) return e->type->ops.bio_merge(hctx, bio, nr_segs); - } type = hctx->type; if ((hctx->flags & BLK_MQ_F_SHOULD_MERGE) && @@ -344,7 +342,6 @@ bool __blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio, spin_unlock(&ctx->lock); } - blk_mq_put_ctx(ctx); return ret; } diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index 7513c8eaabee..da19f0bc8876 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -113,7 +113,6 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data) struct sbq_wait_state *ws; DEFINE_SBQ_WAIT(wait); unsigned int tag_offset; - bool drop_ctx; int tag; if (data->flags & BLK_MQ_REQ_RESERVED) { @@ -136,7 +135,6 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data) return BLK_MQ_TAG_FAIL; ws = bt_wait_ptr(bt, data->hctx); - drop_ctx = data->ctx == NULL; do { struct sbitmap_queue *bt_prev; @@ -161,9 +159,6 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data) if (tag != -1) break; - if (data->ctx) - blk_mq_put_ctx(data->ctx); - bt_prev = bt; io_schedule(); @@ -189,9 +184,6 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data) ws = bt_wait_ptr(bt, data->hctx); } while (1); - if (drop_ctx && data->ctx) - blk_mq_put_ctx(data->ctx); - sbitmap_finish_wait(bt, ws, &wait); found_tag: diff --git a/block/blk-mq.c b/block/blk-mq.c index d89383847d09..0cb1b152f320 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -355,13 +355,13 @@ static struct request *blk_mq_get_request(struct request_queue *q, struct elevator_queue *e = q->elevator; struct request *rq; unsigned int tag; - bool put_ctx_on_error = false; + bool clear_ctx_on_error = false; blk_queue_enter_live(q); data->q = q; if (likely(!data->ctx)) { data->ctx = blk_mq_get_ctx(q); - put_ctx_on_error = true; + clear_ctx_on_error = true; } if (likely(!data->hctx)) data->hctx = blk_mq_map_queue(q, data->cmd_flags, @@ -387,10 +387,8 @@ static struct request *blk_mq_get_request(struct request_queue *q, tag = blk_mq_get_tag(data); if (tag == BLK_MQ_TAG_FAIL) { - if (put_ctx_on_error) { - blk_mq_put_ctx(data->ctx); + if (clear_ctx_on_error) data->ctx = NULL; - } blk_queue_exit(q); return NULL; } @@ -427,8 +425,6 @@ struct request *blk_mq_alloc_request(struct request_queue *q, unsigned int op, if (!rq) return ERR_PTR(-EWOULDBLOCK); - blk_mq_put_ctx(alloc_data.ctx); - rq->__data_len = 0; rq->__sector = (sector_t) -1; rq->bio = rq->biotail = NULL; @@ -1977,7 +1973,6 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) plug = current->plug; if (unlikely(is_flush_fua)) { - blk_mq_put_ctx(data.ctx); blk_mq_bio_to_request(rq, bio, nr_segs); /* bypass scheduler for flush rq */ @@ -1991,7 +1986,6 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) unsigned int request_count = plug->rq_count; struct request *last = NULL; - blk_mq_put_ctx(data.ctx); blk_mq_bio_to_request(rq, bio, nr_segs); if (!request_count) @@ -2025,8 +2019,6 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) blk_add_rq_to_plug(plug, rq); trace_block_plug(q); - blk_mq_put_ctx(data.ctx); - if (same_queue_rq) { data.hctx = same_queue_rq->mq_hctx; trace_block_unplug(q, 1, true); @@ -2035,11 +2027,9 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) } } else if ((q->nr_hw_queues > 1 && is_sync) || (!q->elevator && !data.hctx->dispatch_busy)) { - blk_mq_put_ctx(data.ctx); blk_mq_bio_to_request(rq, bio, nr_segs); blk_mq_try_issue_directly(data.hctx, rq, &cookie); } else { - blk_mq_put_ctx(data.ctx); blk_mq_bio_to_request(rq, bio, nr_segs); blk_mq_sched_insert_request(rq, false, true, true); } diff --git a/block/blk-mq.h b/block/blk-mq.h index 633a5a77ee8b..f4bf5161333e 100644 --- a/block/blk-mq.h +++ b/block/blk-mq.h @@ -151,12 +151,7 @@ static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q, */ static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q) { - return __blk_mq_get_ctx(q, get_cpu()); -} - -static inline void blk_mq_put_ctx(struct blk_mq_ctx *ctx) -{ - put_cpu(); + return __blk_mq_get_ctx(q, raw_smp_processor_id()); } struct blk_mq_alloc_data { diff --git a/block/kyber-iosched.c b/block/kyber-iosched.c index 3c2602601741..34dcea0ef637 100644 --- a/block/kyber-iosched.c +++ b/block/kyber-iosched.c @@ -575,7 +575,6 @@ static bool kyber_bio_merge(struct blk_mq_hw_ctx *hctx, struct bio *bio, spin_lock(&kcq->lock); merged = blk_mq_bio_list_merge(hctx->queue, rq_list, bio, nr_segs); spin_unlock(&kcq->lock); - blk_mq_put_ctx(ctx); return merged; } -- cgit v1.2.3