1/* SPDX-License-Identifier: GPL-2.0-only */ 2/* 3 * Copyright (C) 2021 Red Hat, Inc. All rights reserved. 4 * 5 * This file is released under the GPL. 6 */ 7 8#ifndef DM_IO_TRACKER_H 9#define DM_IO_TRACKER_H 10 11#include <linux/jiffies.h> 12 13struct dm_io_tracker { 14 spinlock_t lock; 15 16 /* 17 * Sectors of in-flight IO. 18 */ 19 sector_t in_flight; 20 21 /* 22 * The time, in jiffies, when this device became idle 23 * (if it is indeed idle). 24 */ 25 unsigned long idle_time; 26 unsigned long last_update_time; 27}; 28 29static inline void dm_iot_init(struct dm_io_tracker *iot) 30{ 31 spin_lock_init(&iot->lock); 32 iot->in_flight = 0ul; 33 iot->idle_time = 0ul; 34 iot->last_update_time = jiffies; 35} 36 37static inline bool dm_iot_idle_for(struct dm_io_tracker *iot, unsigned long j) 38{ 39 bool r = false; 40 41 spin_lock_irq(&iot->lock); 42 if (!iot->in_flight) 43 r = time_after(jiffies, iot->idle_time + j); 44 spin_unlock_irq(&iot->lock); 45 46 return r; 47} 48 49static inline unsigned long dm_iot_idle_time(struct dm_io_tracker *iot) 50{ 51 unsigned long r = 0; 52 53 spin_lock_irq(&iot->lock); 54 if (!iot->in_flight) 55 r = jiffies - iot->idle_time; 56 spin_unlock_irq(&iot->lock); 57 58 return r; 59} 60 61static inline void dm_iot_io_begin(struct dm_io_tracker *iot, sector_t len) 62{ 63 spin_lock_irq(&iot->lock); 64 iot->in_flight += len; 65 spin_unlock_irq(&iot->lock); 66} 67 68static inline void dm_iot_io_end(struct dm_io_tracker *iot, sector_t len) 69{ 70 unsigned long flags; 71 72 if (!len) 73 return; 74 75 spin_lock_irqsave(&iot->lock, flags); 76 iot->in_flight -= len; 77 if (!iot->in_flight) 78 iot->idle_time = jiffies; 79 spin_unlock_irqrestore(&iot->lock, flags); 80} 81 82#endif 83