block/blk-rq-qos.h

   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
  14 struct blk_mq_debugfs_attr;
  15
  16 enum rq_qos_id {
  17         RQ_QOS_WBT,
  18         RQ_QOS_LATENCY,
  19         RQ_QOS_COST,
  20 };
  21
  22 struct rq_wait {
  23         wait_queue_head_t wait;
  24         atomic_t inflight;
  25 };
  26
  27 struct rq_qos {
  28         const struct rq_qos_ops *ops;
  29         struct gendisk *disk;
  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
  37 struct 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
  51 struct 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
  61 static 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
  72 static inline struct rq_qos *wbt_rq_qos(struct request_queue *q)
  73 {
  74         return rq_qos_id(q, RQ_QOS_WBT);
  75 }
  76
  77 static inline struct rq_qos *iolat_rq_qos(struct request_queue *q)
  78 {
  79         return rq_qos_id(q, RQ_QOS_LATENCY);
  80 }
  81
  82 static 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
  88 int rq_qos_add(struct rq_qos *rqos, struct gendisk *disk, enum rq_qos_id id,
  89                 const struct rq_qos_ops *ops);
  90 void rq_qos_del(struct rq_qos *rqos);
  91
  92 typedef bool (acquire_inflight_cb_t)(struct rq_wait *rqw, void *private_data);
  93 typedef void (cleanup_cb_t)(struct rq_wait *rqw, void *private_data);
  94
  95 void rq_qos_wait(struct rq_wait *rqw, void *private_data,
  96                  acquire_inflight_cb_t *acquire_inflight_cb,
  97                  cleanup_cb_t *cleanup_cb);
  98 bool rq_wait_inc_below(struct rq_wait *rq_wait, unsigned int limit);
  99 bool rq_depth_scale_up(struct rq_depth *rqd);
 100 bool rq_depth_scale_down(struct rq_depth *rqd, bool hard_throttle);
 101 bool rq_depth_calc_max_depth(struct rq_depth *rqd);
 102
 103 void __rq_qos_cleanup(struct rq_qos *rqos, struct bio *bio);
 104 void __rq_qos_done(struct rq_qos *rqos, struct request *rq);
 105 void __rq_qos_issue(struct rq_qos *rqos, struct request *rq);
 106 void __rq_qos_requeue(struct rq_qos *rqos, struct request *rq);
 107 void __rq_qos_throttle(struct rq_qos *rqos, struct bio *bio);
 108 void __rq_qos_track(struct rq_qos *rqos, struct request *rq, struct bio *bio);
 109 void __rq_qos_merge(struct rq_qos *rqos, struct request *rq, struct bio *bio);
 110 void __rq_qos_done_bio(struct rq_qos *rqos, struct bio *bio);
 111 void __rq_qos_queue_depth_changed(struct rq_qos *rqos);
 112
 113 static inline void rq_qos_cleanup(struct request_queue *q, struct bio *bio)
 114 {
 115         if (q->rq_qos)
 116                 __rq_qos_cleanup(q->rq_qos, bio);
 117 }
 118
 119 static inline void rq_qos_done(struct request_queue *q, struct request *rq)
 120 {
 121         if (q->rq_qos)
 122                 __rq_qos_done(q->rq_qos, rq);
 123 }
 124
 125 static inline void rq_qos_issue(struct request_queue *q, struct request *rq)
 126 {
 127         if (q->rq_qos)
 128                 __rq_qos_issue(q->rq_qos, rq);
 129 }
 130
 131 static inline void rq_qos_requeue(struct request_queue *q, struct request *rq)
 132 {
 133         if (q->rq_qos)
 134                 __rq_qos_requeue(q->rq_qos, rq);
 135 }
 136
 137 static inline void rq_qos_done_bio(struct bio *bio)
 138 {
 139         if (bio->bi_bdev && (bio_flagged(bio, BIO_QOS_THROTTLED) ||
 140                              bio_flagged(bio, BIO_QOS_MERGED))) {
 141                 struct request_queue *q = bdev_get_queue(bio->bi_bdev);
 142                 if (q->rq_qos)
 143                         __rq_qos_done_bio(q->rq_qos, bio);
 144         }
 145 }
 146
 147 static inline void rq_qos_throttle(struct request_queue *q, struct bio *bio)
 148 {
 149         if (q->rq_qos) {
 150                 bio_set_flag(bio, BIO_QOS_THROTTLED);
 151                 __rq_qos_throttle(q->rq_qos, bio);
 152         }
 153 }
 154
 155 static inline void rq_qos_track(struct request_queue *q, struct request *rq,
 156                                 struct bio *bio)
 157 {
 158         if (q->rq_qos)
 159                 __rq_qos_track(q->rq_qos, rq, bio);
 160 }
 161
 162 static inline void rq_qos_merge(struct request_queue *q, struct request *rq,
 163                                 struct bio *bio)
 164 {
 165         if (q->rq_qos) {
 166                 bio_set_flag(bio, BIO_QOS_MERGED);
 167                 __rq_qos_merge(q->rq_qos, rq, bio);
 168         }
 169 }
 170
 171 static inline void rq_qos_queue_depth_changed(struct request_queue *q)
 172 {
 173         if (q->rq_qos)
 174                 __rq_qos_queue_depth_changed(q->rq_qos);
 175 }
 176
 177 void rq_qos_exit(struct request_queue *);
 178
 179 #endif