tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1#ifndef BLK_INTERNAL_H
2#define BLK_INTERNAL_H
3
4/* Amount of time in which a process may batch requests */
5#define BLK_BATCH_TIME (HZ/50UL)
6
7/* Number of requests a "batching" process may submit */
8#define BLK_BATCH_REQ 32
9
10extern struct kmem_cache *blk_requestq_cachep;
11extern struct kobj_type blk_queue_ktype;
12
13void rq_init(struct request_queue *q, struct request *rq);
14void init_request_from_bio(struct request *req, struct bio *bio);
15void blk_rq_bio_prep(struct request_queue *q, struct request *rq,
16 struct bio *bio);
17void __blk_queue_free_tags(struct request_queue *q);
18
19void blk_unplug_work(struct work_struct *work);
20void blk_unplug_timeout(unsigned long data);
21
22struct io_context *current_io_context(gfp_t gfp_flags, int node);
23
24int ll_back_merge_fn(struct request_queue *q, struct request *req,
25 struct bio *bio);
26int ll_front_merge_fn(struct request_queue *q, struct request *req,
27 struct bio *bio);
28int attempt_back_merge(struct request_queue *q, struct request *rq);
29int attempt_front_merge(struct request_queue *q, struct request *rq);
30void blk_recalc_rq_segments(struct request *rq);
31void blk_recalc_rq_sectors(struct request *rq, int nsect);
32
33void blk_queue_congestion_threshold(struct request_queue *q);
34
35/*
36 * Return the threshold (number of used requests) at which the queue is
37 * considered to be congested. It include a little hysteresis to keep the
38 * context switch rate down.
39 */
40static inline int queue_congestion_on_threshold(struct request_queue *q)
41{
42 return q->nr_congestion_on;
43}
44
45/*
46 * The threshold at which a queue is considered to be uncongested
47 */
48static inline int queue_congestion_off_threshold(struct request_queue *q)
49{
50 return q->nr_congestion_off;
51}
52
53#endif