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git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/blob - block/blk-wbt.h
1 /* SPDX-License-Identifier: GPL-2.0 */
5 #include <linux/kernel.h>
6 #include <linux/atomic.h>
7 #include <linux/wait.h>
8 #include <linux/timer.h>
9 #include <linux/ktime.h>
14 WBT_TRACKED
= 1, /* write, tracked for throttling */
15 WBT_READ
= 2, /* read */
16 WBT_KSWAPD
= 4, /* write, from kswapd */
18 WBT_NR_BITS
= 3, /* number of bits */
28 * Enable states. Either off, or on by default (done at init time),
29 * or on through manual setup in sysfs.
32 WBT_STATE_ON_DEFAULT
= 1,
33 WBT_STATE_ON_MANUAL
= 2,
36 static inline void wbt_clear_state(struct blk_issue_stat
*stat
)
38 stat
->stat
&= ~BLK_STAT_RES_MASK
;
41 static inline enum wbt_flags
wbt_stat_to_mask(struct blk_issue_stat
*stat
)
43 return (stat
->stat
& BLK_STAT_RES_MASK
) >> BLK_STAT_RES_SHIFT
;
46 static inline void wbt_track(struct blk_issue_stat
*stat
, enum wbt_flags wb_acct
)
48 stat
->stat
|= ((u64
) wb_acct
) << BLK_STAT_RES_SHIFT
;
51 static inline bool wbt_is_tracked(struct blk_issue_stat
*stat
)
53 return (stat
->stat
>> BLK_STAT_RES_SHIFT
) & WBT_TRACKED
;
56 static inline bool wbt_is_read(struct blk_issue_stat
*stat
)
58 return (stat
->stat
>> BLK_STAT_RES_SHIFT
) & WBT_READ
;
62 wait_queue_head_t wait
;
68 * Settings that govern how we throttle
70 unsigned int wb_background
; /* background writeback */
71 unsigned int wb_normal
; /* normal writeback */
72 unsigned int wb_max
; /* max throughput writeback */
76 short enable_state
; /* WBT_STATE_* */
79 * Number of consecutive periods where we don't have enough
80 * information to make a firm scale up/down decision.
82 unsigned int unknown_cnt
;
84 u64 win_nsec
; /* default window size */
85 u64 cur_win_nsec
; /* current window size */
87 struct blk_stat_callback
*cb
;
93 unsigned int queue_depth
;
95 unsigned long last_issue
; /* last non-throttled issue */
96 unsigned long last_comp
; /* last non-throttled comp */
97 unsigned long min_lat_nsec
;
98 struct request_queue
*queue
;
99 struct rq_wait rq_wait
[WBT_NUM_RWQ
];
102 static inline unsigned int wbt_inflight(struct rq_wb
*rwb
)
104 unsigned int i
, ret
= 0;
106 for (i
= 0; i
< WBT_NUM_RWQ
; i
++)
107 ret
+= atomic_read(&rwb
->rq_wait
[i
].inflight
);
112 #ifdef CONFIG_BLK_WBT
114 void __wbt_done(struct rq_wb
*, enum wbt_flags
);
115 void wbt_done(struct rq_wb
*, struct blk_issue_stat
*);
116 enum wbt_flags
wbt_wait(struct rq_wb
*, struct bio
*, spinlock_t
*);
117 int wbt_init(struct request_queue
*);
118 void wbt_exit(struct request_queue
*);
119 void wbt_update_limits(struct rq_wb
*);
120 void wbt_requeue(struct rq_wb
*, struct blk_issue_stat
*);
121 void wbt_issue(struct rq_wb
*, struct blk_issue_stat
*);
122 void wbt_disable_default(struct request_queue
*);
123 void wbt_enable_default(struct request_queue
*);
125 void wbt_set_queue_depth(struct rq_wb
*, unsigned int);
126 void wbt_set_write_cache(struct rq_wb
*, bool);
128 u64
wbt_default_latency_nsec(struct request_queue
*);
132 static inline void __wbt_done(struct rq_wb
*rwb
, enum wbt_flags flags
)
135 static inline void wbt_done(struct rq_wb
*rwb
, struct blk_issue_stat
*stat
)
138 static inline enum wbt_flags
wbt_wait(struct rq_wb
*rwb
, struct bio
*bio
,
143 static inline int wbt_init(struct request_queue
*q
)
147 static inline void wbt_exit(struct request_queue
*q
)
150 static inline void wbt_update_limits(struct rq_wb
*rwb
)
153 static inline void wbt_requeue(struct rq_wb
*rwb
, struct blk_issue_stat
*stat
)
156 static inline void wbt_issue(struct rq_wb
*rwb
, struct blk_issue_stat
*stat
)
159 static inline void wbt_disable_default(struct request_queue
*q
)
162 static inline void wbt_enable_default(struct request_queue
*q
)
165 static inline void wbt_set_queue_depth(struct rq_wb
*rwb
, unsigned int depth
)
168 static inline void wbt_set_write_cache(struct rq_wb
*rwb
, bool wc
)
171 static inline u64
wbt_default_latency_nsec(struct request_queue
*q
)
176 #endif /* CONFIG_BLK_WBT */