4 /* Amount of time in which a process may batch requests */
5 #define BLK_BATCH_TIME (HZ/50UL)
7 /* Number of requests a "batching" process may submit */
8 #define BLK_BATCH_REQ 32
10 extern struct kmem_cache
*blk_requestq_cachep
;
11 extern struct kobj_type blk_queue_ktype
;
13 void rq_init(struct request_queue
*q
, struct request
*rq
);
14 void init_request_from_bio(struct request
*req
, struct bio
*bio
);
15 void blk_rq_bio_prep(struct request_queue
*q
, struct request
*rq
,
17 int ll_back_merge_fn(struct request_queue
*q
, struct request
*req
,
19 void __blk_queue_free_tags(struct request_queue
*q
);
21 void blk_unplug_work(struct work_struct
*work
);
22 void blk_unplug_timeout(unsigned long data
);
24 struct io_context
*current_io_context(gfp_t gfp_flags
, int node
);
26 void blk_queue_congestion_threshold(struct request_queue
*q
);
29 * Return the threshold (number of used requests) at which the queue is
30 * considered to be congested. It include a little hysteresis to keep the
31 * context switch rate down.
33 static inline int queue_congestion_on_threshold(struct request_queue
*q
)
35 return q
->nr_congestion_on
;
39 * The threshold at which a queue is considered to be uncongested
41 static inline int queue_congestion_off_threshold(struct request_queue
*q
)
43 return q
->nr_congestion_off
;