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v6.2
  1/* SPDX-License-Identifier: GPL-2.0 */
  2#ifndef RQ_QOS_H
  3#define RQ_QOS_H
  4
  5#include <linux/kernel.h>
  6#include <linux/blkdev.h>
  7#include <linux/blk_types.h>
  8#include <linux/atomic.h>
  9#include <linux/wait.h>
 10#include <linux/blk-mq.h>
 11
 12#include "blk-mq-debugfs.h"
 13
 14struct blk_mq_debugfs_attr;
 15
 16enum rq_qos_id {
 17	RQ_QOS_WBT,
 18	RQ_QOS_LATENCY,
 19	RQ_QOS_COST,
 20};
 21
 22struct rq_wait {
 23	wait_queue_head_t wait;
 24	atomic_t inflight;
 25};
 26
 27struct rq_qos {
 28	struct rq_qos_ops *ops;
 29	struct request_queue *q;
 30	enum rq_qos_id id;
 31	struct rq_qos *next;
 32#ifdef CONFIG_BLK_DEBUG_FS
 33	struct dentry *debugfs_dir;
 34#endif
 35};
 36
 37struct rq_qos_ops {
 38	void (*throttle)(struct rq_qos *, struct bio *);
 39	void (*track)(struct rq_qos *, struct request *, struct bio *);
 40	void (*merge)(struct rq_qos *, struct request *, struct bio *);
 41	void (*issue)(struct rq_qos *, struct request *);
 42	void (*requeue)(struct rq_qos *, struct request *);
 43	void (*done)(struct rq_qos *, struct request *);
 44	void (*done_bio)(struct rq_qos *, struct bio *);
 45	void (*cleanup)(struct rq_qos *, struct bio *);
 46	void (*queue_depth_changed)(struct rq_qos *);
 47	void (*exit)(struct rq_qos *);
 48	const struct blk_mq_debugfs_attr *debugfs_attrs;
 49};
 50
 51struct rq_depth {
 52	unsigned int max_depth;
 53
 54	int scale_step;
 55	bool scaled_max;
 56
 57	unsigned int queue_depth;
 58	unsigned int default_depth;
 59};
 60
 61static inline struct rq_qos *rq_qos_id(struct request_queue *q,
 62				       enum rq_qos_id id)
 63{
 64	struct rq_qos *rqos;
 65	for (rqos = q->rq_qos; rqos; rqos = rqos->next) {
 66		if (rqos->id == id)
 67			break;
 68	}
 69	return rqos;
 70}
 71
 72static inline struct rq_qos *wbt_rq_qos(struct request_queue *q)
 73{
 74	return rq_qos_id(q, RQ_QOS_WBT);
 75}
 76
 77static inline struct rq_qos *blkcg_rq_qos(struct request_queue *q)
 78{
 79	return rq_qos_id(q, RQ_QOS_LATENCY);
 80}
 81
 
 
 
 
 
 
 
 
 
 
 
 
 
 82static inline void rq_wait_init(struct rq_wait *rq_wait)
 83{
 84	atomic_set(&rq_wait->inflight, 0);
 85	init_waitqueue_head(&rq_wait->wait);
 86}
 87
 88static inline int rq_qos_add(struct request_queue *q, struct rq_qos *rqos)
 89{
 90	/*
 91	 * No IO can be in-flight when adding rqos, so freeze queue, which
 92	 * is fine since we only support rq_qos for blk-mq queue.
 93	 *
 94	 * Reuse ->queue_lock for protecting against other concurrent
 95	 * rq_qos adding/deleting
 96	 */
 97	blk_mq_freeze_queue(q);
 98
 99	spin_lock_irq(&q->queue_lock);
100	if (rq_qos_id(q, rqos->id))
101		goto ebusy;
102	rqos->next = q->rq_qos;
103	q->rq_qos = rqos;
104	spin_unlock_irq(&q->queue_lock);
105
106	blk_mq_unfreeze_queue(q);
107
108	if (rqos->ops->debugfs_attrs) {
109		mutex_lock(&q->debugfs_mutex);
110		blk_mq_debugfs_register_rqos(rqos);
111		mutex_unlock(&q->debugfs_mutex);
112	}
113
114	return 0;
115ebusy:
116	spin_unlock_irq(&q->queue_lock);
117	blk_mq_unfreeze_queue(q);
118	return -EBUSY;
119
120}
121
122static inline void rq_qos_del(struct request_queue *q, struct rq_qos *rqos)
123{
124	struct rq_qos **cur;
125
126	/*
127	 * See comment in rq_qos_add() about freezing queue & using
128	 * ->queue_lock.
129	 */
130	blk_mq_freeze_queue(q);
131
132	spin_lock_irq(&q->queue_lock);
133	for (cur = &q->rq_qos; *cur; cur = &(*cur)->next) {
134		if (*cur == rqos) {
135			*cur = rqos->next;
136			break;
137		}
138	}
139	spin_unlock_irq(&q->queue_lock);
140
141	blk_mq_unfreeze_queue(q);
142
143	mutex_lock(&q->debugfs_mutex);
144	blk_mq_debugfs_unregister_rqos(rqos);
145	mutex_unlock(&q->debugfs_mutex);
146}
147
148typedef bool (acquire_inflight_cb_t)(struct rq_wait *rqw, void *private_data);
149typedef void (cleanup_cb_t)(struct rq_wait *rqw, void *private_data);
150
151void rq_qos_wait(struct rq_wait *rqw, void *private_data,
152		 acquire_inflight_cb_t *acquire_inflight_cb,
153		 cleanup_cb_t *cleanup_cb);
154bool rq_wait_inc_below(struct rq_wait *rq_wait, unsigned int limit);
155bool rq_depth_scale_up(struct rq_depth *rqd);
156bool rq_depth_scale_down(struct rq_depth *rqd, bool hard_throttle);
157bool rq_depth_calc_max_depth(struct rq_depth *rqd);
158
159void __rq_qos_cleanup(struct rq_qos *rqos, struct bio *bio);
160void __rq_qos_done(struct rq_qos *rqos, struct request *rq);
161void __rq_qos_issue(struct rq_qos *rqos, struct request *rq);
162void __rq_qos_requeue(struct rq_qos *rqos, struct request *rq);
163void __rq_qos_throttle(struct rq_qos *rqos, struct bio *bio);
164void __rq_qos_track(struct rq_qos *rqos, struct request *rq, struct bio *bio);
165void __rq_qos_merge(struct rq_qos *rqos, struct request *rq, struct bio *bio);
166void __rq_qos_done_bio(struct rq_qos *rqos, struct bio *bio);
167void __rq_qos_queue_depth_changed(struct rq_qos *rqos);
168
169static inline void rq_qos_cleanup(struct request_queue *q, struct bio *bio)
170{
171	if (q->rq_qos)
172		__rq_qos_cleanup(q->rq_qos, bio);
173}
174
175static inline void rq_qos_done(struct request_queue *q, struct request *rq)
176{
177	if (q->rq_qos)
178		__rq_qos_done(q->rq_qos, rq);
179}
180
181static inline void rq_qos_issue(struct request_queue *q, struct request *rq)
182{
183	if (q->rq_qos)
184		__rq_qos_issue(q->rq_qos, rq);
185}
186
187static inline void rq_qos_requeue(struct request_queue *q, struct request *rq)
188{
189	if (q->rq_qos)
190		__rq_qos_requeue(q->rq_qos, rq);
191}
192
193static inline void rq_qos_done_bio(struct bio *bio)
194{
195	if (bio->bi_bdev && (bio_flagged(bio, BIO_QOS_THROTTLED) ||
196			     bio_flagged(bio, BIO_QOS_MERGED))) {
197		struct request_queue *q = bdev_get_queue(bio->bi_bdev);
198		if (q->rq_qos)
199			__rq_qos_done_bio(q->rq_qos, bio);
200	}
201}
202
203static inline void rq_qos_throttle(struct request_queue *q, struct bio *bio)
204{
205	if (q->rq_qos) {
206		bio_set_flag(bio, BIO_QOS_THROTTLED);
 
 
 
 
207		__rq_qos_throttle(q->rq_qos, bio);
208	}
209}
210
211static inline void rq_qos_track(struct request_queue *q, struct request *rq,
212				struct bio *bio)
213{
214	if (q->rq_qos)
215		__rq_qos_track(q->rq_qos, rq, bio);
216}
217
218static inline void rq_qos_merge(struct request_queue *q, struct request *rq,
219				struct bio *bio)
220{
221	if (q->rq_qos) {
222		bio_set_flag(bio, BIO_QOS_MERGED);
223		__rq_qos_merge(q->rq_qos, rq, bio);
224	}
225}
226
227static inline void rq_qos_queue_depth_changed(struct request_queue *q)
228{
229	if (q->rq_qos)
230		__rq_qos_queue_depth_changed(q->rq_qos);
231}
232
233void rq_qos_exit(struct request_queue *);
234
235#endif
v5.9
  1/* SPDX-License-Identifier: GPL-2.0 */
  2#ifndef RQ_QOS_H
  3#define RQ_QOS_H
  4
  5#include <linux/kernel.h>
  6#include <linux/blkdev.h>
  7#include <linux/blk_types.h>
  8#include <linux/atomic.h>
  9#include <linux/wait.h>
 
 10
 11#include "blk-mq-debugfs.h"
 12
 13struct blk_mq_debugfs_attr;
 14
 15enum rq_qos_id {
 16	RQ_QOS_WBT,
 17	RQ_QOS_LATENCY,
 18	RQ_QOS_COST,
 19};
 20
 21struct rq_wait {
 22	wait_queue_head_t wait;
 23	atomic_t inflight;
 24};
 25
 26struct rq_qos {
 27	struct rq_qos_ops *ops;
 28	struct request_queue *q;
 29	enum rq_qos_id id;
 30	struct rq_qos *next;
 31#ifdef CONFIG_BLK_DEBUG_FS
 32	struct dentry *debugfs_dir;
 33#endif
 34};
 35
 36struct rq_qos_ops {
 37	void (*throttle)(struct rq_qos *, struct bio *);
 38	void (*track)(struct rq_qos *, struct request *, struct bio *);
 39	void (*merge)(struct rq_qos *, struct request *, struct bio *);
 40	void (*issue)(struct rq_qos *, struct request *);
 41	void (*requeue)(struct rq_qos *, struct request *);
 42	void (*done)(struct rq_qos *, struct request *);
 43	void (*done_bio)(struct rq_qos *, struct bio *);
 44	void (*cleanup)(struct rq_qos *, struct bio *);
 45	void (*queue_depth_changed)(struct rq_qos *);
 46	void (*exit)(struct rq_qos *);
 47	const struct blk_mq_debugfs_attr *debugfs_attrs;
 48};
 49
 50struct rq_depth {
 51	unsigned int max_depth;
 52
 53	int scale_step;
 54	bool scaled_max;
 55
 56	unsigned int queue_depth;
 57	unsigned int default_depth;
 58};
 59
 60static inline struct rq_qos *rq_qos_id(struct request_queue *q,
 61				       enum rq_qos_id id)
 62{
 63	struct rq_qos *rqos;
 64	for (rqos = q->rq_qos; rqos; rqos = rqos->next) {
 65		if (rqos->id == id)
 66			break;
 67	}
 68	return rqos;
 69}
 70
 71static inline struct rq_qos *wbt_rq_qos(struct request_queue *q)
 72{
 73	return rq_qos_id(q, RQ_QOS_WBT);
 74}
 75
 76static inline struct rq_qos *blkcg_rq_qos(struct request_queue *q)
 77{
 78	return rq_qos_id(q, RQ_QOS_LATENCY);
 79}
 80
 81static inline const char *rq_qos_id_to_name(enum rq_qos_id id)
 82{
 83	switch (id) {
 84	case RQ_QOS_WBT:
 85		return "wbt";
 86	case RQ_QOS_LATENCY:
 87		return "latency";
 88	case RQ_QOS_COST:
 89		return "cost";
 90	}
 91	return "unknown";
 92}
 93
 94static inline void rq_wait_init(struct rq_wait *rq_wait)
 95{
 96	atomic_set(&rq_wait->inflight, 0);
 97	init_waitqueue_head(&rq_wait->wait);
 98}
 99
100static inline void rq_qos_add(struct request_queue *q, struct rq_qos *rqos)
101{
 
 
 
 
 
 
 
 
 
 
 
 
102	rqos->next = q->rq_qos;
103	q->rq_qos = rqos;
 
 
 
104
105	if (rqos->ops->debugfs_attrs)
 
106		blk_mq_debugfs_register_rqos(rqos);
 
 
 
 
 
 
 
 
 
107}
108
109static inline void rq_qos_del(struct request_queue *q, struct rq_qos *rqos)
110{
111	struct rq_qos **cur;
112
 
 
 
 
 
 
 
113	for (cur = &q->rq_qos; *cur; cur = &(*cur)->next) {
114		if (*cur == rqos) {
115			*cur = rqos->next;
116			break;
117		}
118	}
 
 
 
119
 
120	blk_mq_debugfs_unregister_rqos(rqos);
 
121}
122
123typedef bool (acquire_inflight_cb_t)(struct rq_wait *rqw, void *private_data);
124typedef void (cleanup_cb_t)(struct rq_wait *rqw, void *private_data);
125
126void rq_qos_wait(struct rq_wait *rqw, void *private_data,
127		 acquire_inflight_cb_t *acquire_inflight_cb,
128		 cleanup_cb_t *cleanup_cb);
129bool rq_wait_inc_below(struct rq_wait *rq_wait, unsigned int limit);
130bool rq_depth_scale_up(struct rq_depth *rqd);
131bool rq_depth_scale_down(struct rq_depth *rqd, bool hard_throttle);
132bool rq_depth_calc_max_depth(struct rq_depth *rqd);
133
134void __rq_qos_cleanup(struct rq_qos *rqos, struct bio *bio);
135void __rq_qos_done(struct rq_qos *rqos, struct request *rq);
136void __rq_qos_issue(struct rq_qos *rqos, struct request *rq);
137void __rq_qos_requeue(struct rq_qos *rqos, struct request *rq);
138void __rq_qos_throttle(struct rq_qos *rqos, struct bio *bio);
139void __rq_qos_track(struct rq_qos *rqos, struct request *rq, struct bio *bio);
140void __rq_qos_merge(struct rq_qos *rqos, struct request *rq, struct bio *bio);
141void __rq_qos_done_bio(struct rq_qos *rqos, struct bio *bio);
142void __rq_qos_queue_depth_changed(struct rq_qos *rqos);
143
144static inline void rq_qos_cleanup(struct request_queue *q, struct bio *bio)
145{
146	if (q->rq_qos)
147		__rq_qos_cleanup(q->rq_qos, bio);
148}
149
150static inline void rq_qos_done(struct request_queue *q, struct request *rq)
151{
152	if (q->rq_qos)
153		__rq_qos_done(q->rq_qos, rq);
154}
155
156static inline void rq_qos_issue(struct request_queue *q, struct request *rq)
157{
158	if (q->rq_qos)
159		__rq_qos_issue(q->rq_qos, rq);
160}
161
162static inline void rq_qos_requeue(struct request_queue *q, struct request *rq)
163{
164	if (q->rq_qos)
165		__rq_qos_requeue(q->rq_qos, rq);
166}
167
168static inline void rq_qos_done_bio(struct request_queue *q, struct bio *bio)
169{
170	if (q->rq_qos)
171		__rq_qos_done_bio(q->rq_qos, bio);
 
 
 
 
172}
173
174static inline void rq_qos_throttle(struct request_queue *q, struct bio *bio)
175{
176	/*
177	 * BIO_TRACKED lets controllers know that a bio went through the
178	 * normal rq_qos path.
179	 */
180	bio_set_flag(bio, BIO_TRACKED);
181	if (q->rq_qos)
182		__rq_qos_throttle(q->rq_qos, bio);
 
183}
184
185static inline void rq_qos_track(struct request_queue *q, struct request *rq,
186				struct bio *bio)
187{
188	if (q->rq_qos)
189		__rq_qos_track(q->rq_qos, rq, bio);
190}
191
192static inline void rq_qos_merge(struct request_queue *q, struct request *rq,
193				struct bio *bio)
194{
195	if (q->rq_qos)
 
196		__rq_qos_merge(q->rq_qos, rq, bio);
 
197}
198
199static inline void rq_qos_queue_depth_changed(struct request_queue *q)
200{
201	if (q->rq_qos)
202		__rq_qos_queue_depth_changed(q->rq_qos);
203}
204
205void rq_qos_exit(struct request_queue *);
206
207#endif