164 lines
3.6 KiB
C
164 lines
3.6 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef WB_THROTTLE_H
|
|
#define WB_THROTTLE_H
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/atomic.h>
|
|
#include <linux/wait.h>
|
|
#include <linux/timer.h>
|
|
#include <linux/ktime.h>
|
|
|
|
#include "blk-stat.h"
|
|
|
|
enum wbt_flags {
|
|
WBT_TRACKED = 1, /* write, tracked for throttling */
|
|
WBT_READ = 2, /* read */
|
|
WBT_KSWAPD = 4, /* write, from kswapd */
|
|
WBT_DISCARD = 8, /* discard */
|
|
|
|
WBT_NR_BITS = 4, /* number of bits */
|
|
};
|
|
|
|
enum {
|
|
WBT_RWQ_BG = 0,
|
|
WBT_RWQ_KSWAPD,
|
|
WBT_RWQ_DISCARD,
|
|
WBT_NUM_RWQ,
|
|
};
|
|
|
|
/*
|
|
* Enable states. Either off, or on by default (done at init time),
|
|
* or on through manual setup in sysfs.
|
|
*/
|
|
enum {
|
|
WBT_STATE_ON_DEFAULT = 1,
|
|
WBT_STATE_ON_MANUAL = 2,
|
|
};
|
|
|
|
struct rq_wait {
|
|
wait_queue_head_t wait;
|
|
atomic_t inflight;
|
|
};
|
|
|
|
struct rq_wb {
|
|
/*
|
|
* Settings that govern how we throttle
|
|
*/
|
|
unsigned int wb_background; /* background writeback */
|
|
unsigned int wb_normal; /* normal writeback */
|
|
unsigned int wb_max; /* max throughput writeback */
|
|
int scale_step;
|
|
bool scaled_max;
|
|
|
|
short enable_state; /* WBT_STATE_* */
|
|
|
|
/*
|
|
* Number of consecutive periods where we don't have enough
|
|
* information to make a firm scale up/down decision.
|
|
*/
|
|
unsigned int unknown_cnt;
|
|
|
|
u64 win_nsec; /* default window size */
|
|
u64 cur_win_nsec; /* current window size */
|
|
|
|
struct blk_stat_callback *cb;
|
|
|
|
u64 sync_issue;
|
|
void *sync_cookie;
|
|
|
|
unsigned int wc;
|
|
unsigned int queue_depth;
|
|
|
|
unsigned long last_issue; /* last non-throttled issue */
|
|
unsigned long last_comp; /* last non-throttled comp */
|
|
unsigned long min_lat_nsec;
|
|
struct request_queue *queue;
|
|
struct rq_wait rq_wait[WBT_NUM_RWQ];
|
|
};
|
|
|
|
static inline unsigned int wbt_inflight(struct rq_wb *rwb)
|
|
{
|
|
unsigned int i, ret = 0;
|
|
|
|
for (i = 0; i < WBT_NUM_RWQ; i++)
|
|
ret += atomic_read(&rwb->rq_wait[i].inflight);
|
|
|
|
return ret;
|
|
}
|
|
|
|
#ifdef CONFIG_BLK_WBT
|
|
|
|
static inline void wbt_track(struct request *rq, enum wbt_flags flags)
|
|
{
|
|
rq->wbt_flags |= flags;
|
|
}
|
|
|
|
void __wbt_done(struct rq_wb *, enum wbt_flags);
|
|
void wbt_done(struct rq_wb *, struct request *);
|
|
enum wbt_flags wbt_wait(struct rq_wb *, struct bio *, spinlock_t *);
|
|
int wbt_init(struct request_queue *);
|
|
void wbt_exit(struct request_queue *);
|
|
void wbt_update_limits(struct rq_wb *);
|
|
void wbt_requeue(struct rq_wb *, struct request *);
|
|
void wbt_issue(struct rq_wb *, struct request *);
|
|
void wbt_disable_default(struct request_queue *);
|
|
void wbt_enable_default(struct request_queue *);
|
|
|
|
void wbt_set_queue_depth(struct rq_wb *, unsigned int);
|
|
void wbt_set_write_cache(struct rq_wb *, bool);
|
|
|
|
u64 wbt_default_latency_nsec(struct request_queue *);
|
|
|
|
#else
|
|
|
|
static inline void wbt_track(struct request *rq, enum wbt_flags flags)
|
|
{
|
|
}
|
|
static inline void __wbt_done(struct rq_wb *rwb, enum wbt_flags flags)
|
|
{
|
|
}
|
|
static inline void wbt_done(struct rq_wb *rwb, struct request *rq)
|
|
{
|
|
}
|
|
static inline enum wbt_flags wbt_wait(struct rq_wb *rwb, struct bio *bio,
|
|
spinlock_t *lock)
|
|
{
|
|
return 0;
|
|
}
|
|
static inline int wbt_init(struct request_queue *q)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
static inline void wbt_exit(struct request_queue *q)
|
|
{
|
|
}
|
|
static inline void wbt_update_limits(struct rq_wb *rwb)
|
|
{
|
|
}
|
|
static inline void wbt_requeue(struct rq_wb *rwb, struct request *rq)
|
|
{
|
|
}
|
|
static inline void wbt_issue(struct rq_wb *rwb, struct request *rq)
|
|
{
|
|
}
|
|
static inline void wbt_disable_default(struct request_queue *q)
|
|
{
|
|
}
|
|
static inline void wbt_enable_default(struct request_queue *q)
|
|
{
|
|
}
|
|
static inline void wbt_set_queue_depth(struct rq_wb *rwb, unsigned int depth)
|
|
{
|
|
}
|
|
static inline void wbt_set_write_cache(struct rq_wb *rwb, bool wc)
|
|
{
|
|
}
|
|
static inline u64 wbt_default_latency_nsec(struct request_queue *q)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
#endif /* CONFIG_BLK_WBT */
|
|
|
|
#endif
|