[linux-block.git] / block / blk-rq-qos.h

#ifndef RQ_QOS_H
#define RQ_QOS_H

#include <linux/kernel.h>
#include <linux/blkdev.h>
#include <linux/blk_types.h>
#include <linux/atomic.h>
#include <linux/wait.h>

enum rq_qos_id {
	RQ_QOS_WBT,
	RQ_QOS_CGROUP,
};

struct rq_wait {
	wait_queue_head_t wait;
	atomic_t inflight;
};

struct rq_qos {
	struct rq_qos_ops *ops;
	struct request_queue *q;
	enum rq_qos_id id;
	struct rq_qos *next;
};

struct rq_qos_ops {
	void (*throttle)(struct rq_qos *, struct bio *, spinlock_t *);
	void (*track)(struct rq_qos *, struct request *, struct bio *);
	void (*issue)(struct rq_qos *, struct request *);
	void (*requeue)(struct rq_qos *, struct request *);
	void (*done)(struct rq_qos *, struct request *);
	void (*cleanup)(struct rq_qos *, struct bio *);
	void (*exit)(struct rq_qos *);
};

struct rq_depth {
	unsigned int max_depth;

	int scale_step;
	bool scaled_max;

	unsigned int queue_depth;
	unsigned int default_depth;
};

static inline struct rq_qos *rq_qos_id(struct request_queue *q,
				       enum rq_qos_id id)
{
	struct rq_qos *rqos;
	for (rqos = q->rq_qos; rqos; rqos = rqos->next) {
		if (rqos->id == id)
			break;
	}
	return rqos;
}

static inline struct rq_qos *wbt_rq_qos(struct request_queue *q)
{
	return rq_qos_id(q, RQ_QOS_WBT);
}

static inline struct rq_qos *blkcg_rq_qos(struct request_queue *q)
{
	return rq_qos_id(q, RQ_QOS_CGROUP);
}

static inline void rq_wait_init(struct rq_wait *rq_wait)
{
	atomic_set(&rq_wait->inflight, 0);
	init_waitqueue_head(&rq_wait->wait);
}

static inline void rq_qos_add(struct request_queue *q, struct rq_qos *rqos)
{
	rqos->next = q->rq_qos;
	q->rq_qos = rqos;
}

static inline void rq_qos_del(struct request_queue *q, struct rq_qos *rqos)
{
	struct rq_qos *cur, *prev = NULL;
	for (cur = q->rq_qos; cur; cur = cur->next) {
		if (cur == rqos) {
			if (prev)
				prev->next = rqos->next;
			else
				q->rq_qos = cur;
			break;
		}
		prev = cur;
	}
}

bool rq_wait_inc_below(struct rq_wait *rq_wait, int limit);
void rq_depth_scale_up(struct rq_depth *rqd);
void rq_depth_scale_down(struct rq_depth *rqd, bool hard_throttle);
bool rq_depth_calc_max_depth(struct rq_depth *rqd);

void rq_qos_cleanup(struct request_queue *, struct bio *);
void rq_qos_done(struct request_queue *, struct request *);
void rq_qos_issue(struct request_queue *, struct request *);
void rq_qos_requeue(struct request_queue *, struct request *);
void rq_qos_throttle(struct request_queue *, struct bio *, spinlock_t *);
void rq_qos_track(struct request_queue *q, struct request *, struct bio *);
void rq_qos_exit(struct request_queue *);
#endif
Commit	Line	Data
a7905043 JB	1	#ifndef RQ_QOS_H
	2	#define RQ_QOS_H
	3
	4	#include <linux/kernel.h>
	5	#include <linux/blkdev.h>
	6	#include <linux/blk_types.h>
	7	#include <linux/atomic.h>
	8	#include <linux/wait.h>
	9
	10	enum rq_qos_id {
	11	RQ_QOS_WBT,
	12	RQ_QOS_CGROUP,
	13	};
	14
	15	struct rq_wait {
	16	wait_queue_head_t wait;
	17	atomic_t inflight;
	18	};
	19
	20	struct rq_qos {
	21	struct rq_qos_ops *ops;
	22	struct request_queue *q;
	23	enum rq_qos_id id;
	24	struct rq_qos *next;
	25	};
	26
	27	struct rq_qos_ops {
c1c80384 JB	28	void (throttle)(struct rq_qos , struct bio , spinlock_t );
c1c80384 JB	29	void (track)(struct rq_qos , struct request , struct bio );
a7905043 JB	30	void (issue)(struct rq_qos , struct request *);
	31	void (requeue)(struct rq_qos , struct request *);
	32	void (done)(struct rq_qos , struct request *);
c1c80384	33	void (cleanup)(struct rq_qos , struct bio *);
a7905043 JB	34	void (exit)(struct rq_qos );
	35	};
	36
	37	struct rq_depth {
	38	unsigned int max_depth;
	39
	40	int scale_step;
	41	bool scaled_max;
	42
	43	unsigned int queue_depth;
	44	unsigned int default_depth;
	45	};
	46
	47	static inline struct rq_qos rq_qos_id(struct request_queue q,
	48	enum rq_qos_id id)
	49	{
	50	struct rq_qos *rqos;
	51	for (rqos = q->rq_qos; rqos; rqos = rqos->next) {
	52	if (rqos->id == id)
	53	break;
	54	}
	55	return rqos;
	56	}
	57
	58	static inline struct rq_qos wbt_rq_qos(struct request_queue q)
	59	{
	60	return rq_qos_id(q, RQ_QOS_WBT);
	61	}
	62
	63	static inline struct rq_qos blkcg_rq_qos(struct request_queue q)
	64	{
	65	return rq_qos_id(q, RQ_QOS_CGROUP);
	66	}
	67
	68	static inline void rq_wait_init(struct rq_wait *rq_wait)
	69	{
	70	atomic_set(&rq_wait->inflight, 0);
	71	init_waitqueue_head(&rq_wait->wait);
	72	}
	73
	74	static inline void rq_qos_add(struct request_queue q, struct rq_qos rqos)
	75	{
	76	rqos->next = q->rq_qos;
	77	q->rq_qos = rqos;
	78	}
	79
	80	static inline void rq_qos_del(struct request_queue q, struct rq_qos rqos)
	81	{
	82	struct rq_qos cur, prev = NULL;
	83	for (cur = q->rq_qos; cur; cur = cur->next) {
	84	if (cur == rqos) {
	85	if (prev)
	86	prev->next = rqos->next;
	87	else
	88	q->rq_qos = cur;
	89	break;
	90	}
	91	prev = cur;
	92	}
	93	}
	94
	95	bool rq_wait_inc_below(struct rq_wait *rq_wait, int limit);
	96	void rq_depth_scale_up(struct rq_depth *rqd);
	97	void rq_depth_scale_down(struct rq_depth *rqd, bool hard_throttle);
98	bool rq_depth_calc_max_depth(struct rq_depth *rqd);
99
c1c80384	100	void rq_qos_cleanup(struct request_queue , struct bio );
a7905043 JB	101	void rq_qos_done(struct request_queue , struct request );
	102	void rq_qos_issue(struct request_queue , struct request );
	103	void rq_qos_requeue(struct request_queue , struct request );
c1c80384 JB	104	void rq_qos_throttle(struct request_queue , struct bio , spinlock_t *);
c1c80384 JB	105	void rq_qos_track(struct request_queue q, struct request , struct bio *);
a7905043 JB	106	void rq_qos_exit(struct request_queue *);
a7905043 JB	107	#endif