block: Provide blk_mq_sched_get_icq()

Currently we lookup ICQ only after the request is allocated. However BFQ
will want to decide how many scheduler tags it allows a given bfq queue
(effectively a process) to consume based on cgroup weight. So provide a
function blk_mq_sched_get_icq() so that BFQ can lookup ICQ earlier.

Acked-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20211125133645.27483-1-jack@suse.cz
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jan Kara 2021-11-25 14:36:34 +01:00 committed by Jens Axboe
parent 639d353143
commit 790cf9c848
2 changed files with 16 additions and 11 deletions

View File

@ -18,9 +18,8 @@
#include "blk-mq-tag.h"
#include "blk-wbt.h"
void blk_mq_sched_assign_ioc(struct request *rq)
struct io_cq *blk_mq_sched_get_icq(struct request_queue *q)
{
struct request_queue *q = rq->q;
struct io_context *ioc;
struct io_cq *icq;
@ -28,22 +27,27 @@ void blk_mq_sched_assign_ioc(struct request *rq)
if (unlikely(!current->io_context))
create_task_io_context(current, GFP_ATOMIC, q->node);
/*
* May not have an IO context if it's a passthrough request
*/
/* May not have an IO context if context creation failed */
ioc = current->io_context;
if (!ioc)
return;
return NULL;
spin_lock_irq(&q->queue_lock);
icq = ioc_lookup_icq(ioc, q);
spin_unlock_irq(&q->queue_lock);
if (icq)
return icq;
return ioc_create_icq(ioc, q, GFP_ATOMIC);
}
EXPORT_SYMBOL(blk_mq_sched_get_icq);
if (!icq) {
icq = ioc_create_icq(ioc, q, GFP_ATOMIC);
void blk_mq_sched_assign_ioc(struct request *rq)
{
struct io_cq *icq;
icq = blk_mq_sched_get_icq(rq->q);
if (!icq)
return;
}
get_io_context(icq->ioc);
rq->elv.icq = icq;
}

View File

@ -8,6 +8,7 @@
#define MAX_SCHED_RQ (16 * BLKDEV_DEFAULT_RQ)
struct io_cq *blk_mq_sched_get_icq(struct request_queue *q);
void blk_mq_sched_assign_ioc(struct request *rq);
bool blk_mq_sched_try_merge(struct request_queue *q, struct bio *bio,