Commit 8a5ecdd4 authored by Tejun Heo's avatar Tejun Heo Committed by Jens Axboe
Browse files

block: add q->nr_rqs[] and move q->rq.elvpriv to q->nr_rqs_elvpriv 



Add q->nr_rqs[] which currently behaves the same as q->rq.count[] and
move q->rq.elvpriv to q->nr_rqs_elvpriv.  blk_drain_queue() is updated
to use q->nr_rqs[] instead of q->rq.count[].

These counters separates queue-wide request statistics from the
request list and allow implementation of per-queue request allocation.

While at it, properly indent fields of struct request_list.

Signed-off-by: default avatarTejun Heo <tj@kernel.org>
Acked-by: default avatarVivek Goyal <vgoyal@redhat.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent b1208b56

block/blk-core.c

+7 −6
Original line number Diff line number Diff line
@@ -387,7 +387,7 @@ void blk_drain_queue(struct request_queue *q, bool drain_all) 
		if (!list_empty(&q->queue_head) && q->request_fn)

			__blk_run_queue(q);



		drain |= q->rq.elvpriv;

		drain |= q->nr_rqs_elvpriv;



		/*

		 * Unfortunately, requests are queued at and tracked from
@@ -397,7 +397,7 @@ void blk_drain_queue(struct request_queue *q, bool drain_all) 
		if (drain_all) {

			drain |= !list_empty(&q->queue_head);

			for (i = 0; i < 2; i++) {

				drain |= q->rq.count[i];

				drain |= q->nr_rqs[i];

				drain |= q->in_flight[i];

				drain |= !list_empty(&q->flush_queue[i]);

			}
@@ -526,7 +526,6 @@ static int blk_init_free_list(struct request_queue *q) 


	rl->count[BLK_RW_SYNC] = rl->count[BLK_RW_ASYNC] = 0;

	rl->starved[BLK_RW_SYNC] = rl->starved[BLK_RW_ASYNC] = 0;

	rl->elvpriv = 0;

	init_waitqueue_head(&rl->wait[BLK_RW_SYNC]);

	init_waitqueue_head(&rl->wait[BLK_RW_ASYNC]);
@@ -791,9 +790,10 @@ static void freed_request(struct request_queue *q, unsigned int flags) 
	struct request_list *rl = &q->rq;

	int sync = rw_is_sync(flags);



	q->nr_rqs[sync]--;

	rl->count[sync]--;

	if (flags & REQ_ELVPRIV)

		rl->elvpriv--;

		q->nr_rqs_elvpriv--;



	__freed_request(q, sync);
@@ -902,6 +902,7 @@ static struct request *__get_request(struct request_queue *q, int rw_flags, 
	if (rl->count[is_sync] >= (3 * q->nr_requests / 2))

		return NULL;



	q->nr_rqs[is_sync]++;

	rl->count[is_sync]++;

	rl->starved[is_sync] = 0;
@@ -917,7 +918,7 @@ static struct request *__get_request(struct request_queue *q, int rw_flags, 
	 */

	if (blk_rq_should_init_elevator(bio) && !blk_queue_bypass(q)) {

		rw_flags |= REQ_ELVPRIV;

		rl->elvpriv++;

		q->nr_rqs_elvpriv++;

		if (et->icq_cache && ioc)

			icq = ioc_lookup_icq(ioc, q);

	}
@@ -978,7 +979,7 @@ fail_elvpriv: 
	rq->elv.icq = NULL;



	spin_lock_irq(q->queue_lock);

	rl->elvpriv--;

	q->nr_rqs_elvpriv--;

	spin_unlock_irq(q->queue_lock);

	goto out;

include/linux/blkdev.h

+6 −5
Original line number Diff line number Diff line
@@ -53,7 +53,6 @@ struct request_list { 
	 */

	int			count[2];

	int			starved[2];

	int elvpriv;

	mempool_t		*rq_pool;

	wait_queue_head_t	wait[2];

};
@@ -282,6 +281,8 @@ struct request_queue { 
	struct list_head	queue_head;

	struct request		*last_merge;

	struct elevator_queue	*elevator;

	int			nr_rqs[2];	/* # allocated [a]sync rqs */

	int			nr_rqs_elvpriv;	/* # allocated rqs w/ elvpriv */



	/*

	 * the queue request freelist, one for reads and one for writes

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