Linux-Block Archive on lore.kernel.org
 help / color / Atom feed
From: Christoph Hellwig <hch@lst.de>
To: unlisted-recipients:; (no To-header on input)
Cc: linux-block@vger.kernel.org, John Garry <john.garry@huawei.com>,
	Bart Van Assche <bvanassche@acm.org>,
	Hannes Reinecke <hare@suse.com>,
	Thomas Gleixner <tglx@linutronix.de>
Subject: [PATCH 6/9] blk-mq: don't set data->ctx and data->hctx in __blk_mq_alloc_request
Date: Mon, 18 May 2020 08:39:34 +0200
Message-ID: <20200518063937.757218-7-hch@lst.de> (raw)
In-Reply-To: <20200518063937.757218-1-hch@lst.de>

Now that blk_mq_alloc_request_hctx doesn't set ->ctx and ->hctx itself,
all setting of it can be done in the low-level blk_mq_get_tag helper.

Based on patch from Ming Lei <ming.lei@redhat.com>.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 block/blk-mq-tag.c |  8 +++++++-
 block/blk-mq.c     | 15 +--------------
 block/blk-mq.h     |  4 ++--
 3 files changed, 10 insertions(+), 17 deletions(-)

diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
index e5b17300ec882..b526f1f5a3bf3 100644
--- a/block/blk-mq-tag.c
+++ b/block/blk-mq-tag.c
@@ -101,13 +101,19 @@ static int __blk_mq_get_tag(struct blk_mq_alloc_data *data,
 
 unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
 {
-	struct blk_mq_tags *tags = blk_mq_tags_from_data(data);
+	struct blk_mq_tags *tags;
 	struct sbitmap_queue *bt;
 	struct sbq_wait_state *ws;
 	DEFINE_SBQ_WAIT(wait);
 	unsigned int tag_offset;
 	int tag;
 
+	data->ctx = blk_mq_get_ctx(data->q);
+	data->hctx = blk_mq_map_queue(data->q, data->cmd_flags, data->ctx);
+	tags = blk_mq_tags_from_data(data);
+	if (!(data->flags & BLK_MQ_REQ_INTERNAL))
+		blk_mq_tag_busy(data->hctx);
+
 	if (data->flags & BLK_MQ_REQ_RESERVED) {
 		if (unlikely(!tags->nr_reserved_tags)) {
 			WARN_ON_ONCE(1);
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 540b5845cd1d3..74c2d8f61426c 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -276,7 +276,6 @@ static struct request *__blk_mq_alloc_request(struct blk_mq_alloc_data *data)
 	struct elevator_queue *e = q->elevator;
 	struct request *rq;
 	unsigned int tag;
-	bool clear_ctx_on_error = false;
 	req_flags_t rq_flags = 0;
 	u64 alloc_time_ns = 0;
 
@@ -284,13 +283,6 @@ static struct request *__blk_mq_alloc_request(struct blk_mq_alloc_data *data)
 	if (blk_queue_rq_alloc_time(q))
 		alloc_time_ns = ktime_get_ns();
 
-	if (likely(!data->ctx)) {
-		data->ctx = blk_mq_get_ctx(q);
-		clear_ctx_on_error = true;
-	}
-	if (likely(!data->hctx))
-		data->hctx = blk_mq_map_queue(q, data->cmd_flags,
-						data->ctx);
 	if (data->cmd_flags & REQ_NOWAIT)
 		data->flags |= BLK_MQ_REQ_NOWAIT;
 
@@ -306,16 +298,11 @@ static struct request *__blk_mq_alloc_request(struct blk_mq_alloc_data *data)
 		    e->type->ops.limit_depth &&
 		    !(data->flags & BLK_MQ_REQ_RESERVED))
 			e->type->ops.limit_depth(data->cmd_flags, data);
-	} else {
-		blk_mq_tag_busy(data->hctx);
 	}
 
 	tag = blk_mq_get_tag(data);
-	if (tag == BLK_MQ_TAG_FAIL) {
-		if (clear_ctx_on_error)
-			data->ctx = NULL;
+	if (tag == BLK_MQ_TAG_FAIL)
 		return NULL;
-	}
 
 	if (data->flags & BLK_MQ_REQ_INTERNAL) {
 		rq = data->hctx->sched_tags->static_rqs[tag];
diff --git a/block/blk-mq.h b/block/blk-mq.h
index 82921b30b6afa..1338be9d51777 100644
--- a/block/blk-mq.h
+++ b/block/blk-mq.h
@@ -146,13 +146,13 @@ static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q)
 }
 
 struct blk_mq_alloc_data {
-	/* input parameter */
+	/* input parameters */
 	struct request_queue *q;
 	blk_mq_req_flags_t flags;
 	unsigned int shallow_depth;
 	unsigned int cmd_flags;
 
-	/* input & output parameter */
+	/* output parameters */
 	struct blk_mq_ctx *ctx;
 	struct blk_mq_hw_ctx *hctx;
 
-- 
2.26.2


  parent reply index

Thread overview: 47+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-05-18  6:39 blk-mq: improvement CPU hotplug (simplified version) v2 Christoph Hellwig
2020-05-18  6:39 ` [PATCH 1/9] blk-mq: split out a __blk_mq_get_driver_tag helper Christoph Hellwig
2020-05-18  6:39 ` [PATCH 2/9] blk-mq: remove the bio argument to ->prepare_request Christoph Hellwig
2020-05-18  6:39 ` [PATCH 3/9] blk-mq: simplify the blk_mq_get_request calling convention Christoph Hellwig
2020-05-18  6:39 ` [PATCH 4/9] blk-mq: merge blk_mq_rq_ctx_init into __blk_mq_alloc_request Christoph Hellwig
2020-05-18  6:39 ` [PATCH 5/9] blk-mq: don't set data->ctx and data->hctx in blk_mq_alloc_request_hctx Christoph Hellwig
2020-05-18  8:32   ` Thomas Gleixner
2020-05-18  9:31     ` Ming Lei
2020-05-18 10:42       ` Thomas Gleixner
2020-05-18 11:54         ` Ming Lei
2020-05-18 13:16           ` Christoph Hellwig
2020-05-18 14:11             ` Ming Lei
2020-05-18 16:56               ` Christoph Hellwig
2020-05-18 18:38                 ` Thomas Gleixner
2020-05-18 18:45                   ` Christoph Hellwig
2020-05-18 18:59                     ` Thomas Gleixner
2020-05-19  1:54                 ` Ming Lei
2020-05-19 15:30                   ` Christoph Hellwig
2020-05-20  1:18                     ` Ming Lei
2020-05-20  3:04                       ` Ming Lei
2020-05-20  8:03                         ` io_uring vs CPU hotplug, was " Christoph Hellwig
2020-05-20 14:45                           ` Jens Axboe
2020-05-20 15:20                             ` Jens Axboe
2020-05-20 15:31                               ` Christoph Hellwig
2020-05-20 19:41                               ` Thomas Gleixner
2020-05-20 20:18                                 ` Jens Axboe
2020-05-20 22:14                                   ` Thomas Gleixner
2020-05-20 22:40                                     ` Jens Axboe
2020-05-21  2:27                                     ` Ming Lei
2020-05-21  8:13                                       ` Thomas Gleixner
2020-05-21  9:23                                         ` Ming Lei
2020-05-21 18:39                                           ` Thomas Gleixner
2020-05-21 18:45                                             ` Jens Axboe
2020-05-21 20:00                                               ` Thomas Gleixner
2020-05-22  1:57                                             ` Ming Lei
2020-05-18 18:47             ` Thomas Gleixner
2020-05-18 13:18           ` Thomas Gleixner
2020-05-18  6:39 ` Christoph Hellwig [this message]
2020-05-18  6:39 ` [PATCH 7/9] blk-mq: disable preemption during allocating request tag Christoph Hellwig
2020-05-18  6:39 ` [PATCH 8/9] blk-mq: add blk_mq_all_tag_iter Christoph Hellwig
2020-05-18  6:39 ` [PATCH 9/9] blk-mq: drain I/O when all CPUs in a hctx are offline Christoph Hellwig
2020-05-18  8:42   ` John Garry
2020-05-18  9:21     ` Ming Lei
2020-05-18 11:49 ` blk-mq: improvement CPU hotplug (simplified version) v2 John Garry
2020-05-19 15:30   ` Christoph Hellwig
2020-05-19 17:17     ` John Garry
2020-05-20 14:35     ` John Garry

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200518063937.757218-7-hch@lst.de \
    --to=hch@lst.de \
    --cc=bvanassche@acm.org \
    --cc=hare@suse.com \
    --cc=john.garry@huawei.com \
    --cc=linux-block@vger.kernel.org \
    --cc=tglx@linutronix.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-Block Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-block/0 linux-block/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-block linux-block/ https://lore.kernel.org/linux-block \
		linux-block@vger.kernel.org
	public-inbox-index linux-block

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-block


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git