linux/block/blk-mq-sched.h
Omar Sandoval d38d351555 blk-mq-sched: separate mark hctx and queue restart operations
In blk_mq_sched_dispatch_requests(), we call blk_mq_sched_mark_restart()
after we dispatch requests left over on our hardware queue dispatch
list. This is so we'll go back and dispatch requests from the scheduler.
In this case, it's only necessary to restart the hardware queue that we
are running; there's no reason to run other hardware queues just because
we are using shared tags.

So, split out blk_mq_sched_mark_restart() into two operations, one for
just the hardware queue and one for the whole request queue. The core
code only needs the hctx variant, but I/O schedulers will want to use
both.

This also requires adjusting blk_mq_sched_restart_queues() to always
check the queue restart flag, not just when using shared tags.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-02-23 11:55:47 -07:00

154 lines
4.3 KiB
C

#ifndef BLK_MQ_SCHED_H
#define BLK_MQ_SCHED_H
#include "blk-mq.h"
#include "blk-mq-tag.h"
int blk_mq_sched_init_hctx_data(struct request_queue *q, size_t size,
int (*init)(struct blk_mq_hw_ctx *),
void (*exit)(struct blk_mq_hw_ctx *));
void blk_mq_sched_free_hctx_data(struct request_queue *q,
void (*exit)(struct blk_mq_hw_ctx *));
struct request *blk_mq_sched_get_request(struct request_queue *q, struct bio *bio, unsigned int op, struct blk_mq_alloc_data *data);
void blk_mq_sched_put_request(struct request *rq);
void blk_mq_sched_request_inserted(struct request *rq);
bool blk_mq_sched_try_merge(struct request_queue *q, struct bio *bio,
struct request **merged_request);
bool __blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio);
bool blk_mq_sched_try_insert_merge(struct request_queue *q, struct request *rq);
void blk_mq_sched_restart_queues(struct blk_mq_hw_ctx *hctx);
void blk_mq_sched_insert_request(struct request *rq, bool at_head,
bool run_queue, bool async, bool can_block);
void blk_mq_sched_insert_requests(struct request_queue *q,
struct blk_mq_ctx *ctx,
struct list_head *list, bool run_queue_async);
void blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx);
void blk_mq_sched_move_to_dispatch(struct blk_mq_hw_ctx *hctx,
struct list_head *rq_list,
struct request *(*get_rq)(struct blk_mq_hw_ctx *));
int blk_mq_sched_setup(struct request_queue *q);
void blk_mq_sched_teardown(struct request_queue *q);
int blk_mq_sched_init(struct request_queue *q);
static inline bool
blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio)
{
struct elevator_queue *e = q->elevator;
if (!e || blk_queue_nomerges(q) || !bio_mergeable(bio))
return false;
return __blk_mq_sched_bio_merge(q, bio);
}
static inline int blk_mq_sched_get_rq_priv(struct request_queue *q,
struct request *rq,
struct bio *bio)
{
struct elevator_queue *e = q->elevator;
if (e && e->type->ops.mq.get_rq_priv)
return e->type->ops.mq.get_rq_priv(q, rq, bio);
return 0;
}
static inline void blk_mq_sched_put_rq_priv(struct request_queue *q,
struct request *rq)
{
struct elevator_queue *e = q->elevator;
if (e && e->type->ops.mq.put_rq_priv)
e->type->ops.mq.put_rq_priv(q, rq);
}
static inline bool
blk_mq_sched_allow_merge(struct request_queue *q, struct request *rq,
struct bio *bio)
{
struct elevator_queue *e = q->elevator;
if (e && e->type->ops.mq.allow_merge)
return e->type->ops.mq.allow_merge(q, rq, bio);
return true;
}
static inline void
blk_mq_sched_completed_request(struct blk_mq_hw_ctx *hctx, struct request *rq)
{
struct elevator_queue *e = hctx->queue->elevator;
if (e && e->type->ops.mq.completed_request)
e->type->ops.mq.completed_request(hctx, rq);
BUG_ON(rq->internal_tag == -1);
blk_mq_put_tag(hctx, hctx->sched_tags, rq->mq_ctx, rq->internal_tag);
}
static inline void blk_mq_sched_started_request(struct request *rq)
{
struct request_queue *q = rq->q;
struct elevator_queue *e = q->elevator;
if (e && e->type->ops.mq.started_request)
e->type->ops.mq.started_request(rq);
}
static inline void blk_mq_sched_requeue_request(struct request *rq)
{
struct request_queue *q = rq->q;
struct elevator_queue *e = q->elevator;
if (e && e->type->ops.mq.requeue_request)
e->type->ops.mq.requeue_request(rq);
}
static inline bool blk_mq_sched_has_work(struct blk_mq_hw_ctx *hctx)
{
struct elevator_queue *e = hctx->queue->elevator;
if (e && e->type->ops.mq.has_work)
return e->type->ops.mq.has_work(hctx);
return false;
}
/*
* Mark a hardware queue as needing a restart.
*/
static inline void blk_mq_sched_mark_restart_hctx(struct blk_mq_hw_ctx *hctx)
{
if (!test_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state))
set_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state);
}
/*
* Mark a hardware queue and the request queue it belongs to as needing a
* restart.
*/
static inline void blk_mq_sched_mark_restart_queue(struct blk_mq_hw_ctx *hctx)
{
struct request_queue *q = hctx->queue;
if (!test_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state))
set_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state);
if (!test_bit(QUEUE_FLAG_RESTART, &q->queue_flags))
set_bit(QUEUE_FLAG_RESTART, &q->queue_flags);
}
static inline bool blk_mq_sched_needs_restart(struct blk_mq_hw_ctx *hctx)
{
return test_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state);
}
#endif