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 13 struct blk_mq_debugfs_attr; 14 15 enum rq_qos_id { 16 RQ_QOS_WBT, 17 RQ_QOS_LATENCY, 18 RQ_QOS_COST, 19 }; 20 21 struct rq_wait { 22 wait_queue_head_t wait; 23 atomic_t inflight; 24 }; 25 26 struct 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 36 struct 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 50 struct 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 60 static 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 71 static inline struct rq_qos *wbt_rq_qos(struct request_queue *q) 72 { 73 return rq_qos_id(q, RQ_QOS_WBT); 74 } 75 76 static inline struct rq_qos *blkcg_rq_qos(struct request_queue *q) 77 { 78 return rq_qos_id(q, RQ_QOS_LATENCY); 79 } 80 81 static 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 94 static 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 } 99 100 static 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 } 108 109 static 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 } 122 123 typedef bool (acquire_inflight_cb_t)(struct rq_wait *rqw, void *private_data); 124 typedef void (cleanup_cb_t)(struct rq_wait *rqw, void *private_data); 125 126 void rq_qos_wait(struct rq_wait *rqw, void *private_data, 127 acquire_inflight_cb_t *acquire_inflight_cb, 128 cleanup_cb_t *cleanup_cb); 129 bool rq_wait_inc_below(struct rq_wait *rq_wait, unsigned int limit); 130 bool rq_depth_scale_up(struct rq_depth *rqd); 131 bool rq_depth_scale_down(struct rq_depth *rqd, bool hard_throttle); 132 bool rq_depth_calc_max_depth(struct rq_depth *rqd); 133 134 void __rq_qos_cleanup(struct rq_qos *rqos, struct bio *bio); 135 void __rq_qos_done(struct rq_qos *rqos, struct request *rq); 136 void __rq_qos_issue(struct rq_qos *rqos, struct request *rq); 137 void __rq_qos_requeue(struct rq_qos *rqos, struct request *rq); 138 void __rq_qos_throttle(struct rq_qos *rqos, struct bio *bio); 139 void __rq_qos_track(struct rq_qos *rqos, struct request *rq, struct bio *bio); 140 void __rq_qos_merge(struct rq_qos *rqos, struct request *rq, struct bio *bio); 141 void __rq_qos_done_bio(struct rq_qos *rqos, struct bio *bio); 142 void __rq_qos_queue_depth_changed(struct rq_qos *rqos); 143 144 static 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 } 149 150 static 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 } 155 156 static 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 } 161 162 static 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 } 167 168 static 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 } 173 174 static 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 } 184 185 static 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 } 191 192 static 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 } 198 199 static 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 } 204 205 void rq_qos_exit(struct request_queue *); 206 207 #endif 208