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