| Kyle Swenson | 8d8f654 | 2021-03-15 11:02:55 -0600 | [diff] [blame^] | 1 | /* |
| 2 | * fs/f2fs/gc.h |
| 3 | * |
| 4 | * Copyright (c) 2012 Samsung Electronics Co., Ltd. |
| 5 | * http://www.samsung.com/ |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License version 2 as |
| 9 | * published by the Free Software Foundation. |
| 10 | */ |
| 11 | #define GC_THREAD_MIN_WB_PAGES 1 /* |
| 12 | * a threshold to determine |
| 13 | * whether IO subsystem is idle |
| 14 | * or not |
| 15 | */ |
| 16 | #define DEF_GC_THREAD_MIN_SLEEP_TIME 30000 /* milliseconds */ |
| 17 | #define DEF_GC_THREAD_MAX_SLEEP_TIME 60000 |
| 18 | #define DEF_GC_THREAD_NOGC_SLEEP_TIME 300000 /* wait 5 min */ |
| 19 | #define LIMIT_INVALID_BLOCK 40 /* percentage over total user space */ |
| 20 | #define LIMIT_FREE_BLOCK 40 /* percentage over invalid + free space */ |
| 21 | |
| 22 | /* Search max. number of dirty segments to select a victim segment */ |
| 23 | #define DEF_MAX_VICTIM_SEARCH 4096 /* covers 8GB */ |
| 24 | |
| 25 | struct f2fs_gc_kthread { |
| 26 | struct task_struct *f2fs_gc_task; |
| 27 | wait_queue_head_t gc_wait_queue_head; |
| 28 | |
| 29 | /* for gc sleep time */ |
| 30 | unsigned int min_sleep_time; |
| 31 | unsigned int max_sleep_time; |
| 32 | unsigned int no_gc_sleep_time; |
| 33 | |
| 34 | /* for changing gc mode */ |
| 35 | unsigned int gc_idle; |
| 36 | }; |
| 37 | |
| 38 | struct gc_inode_list { |
| 39 | struct list_head ilist; |
| 40 | struct radix_tree_root iroot; |
| 41 | }; |
| 42 | |
| 43 | /* |
| 44 | * inline functions |
| 45 | */ |
| 46 | static inline block_t free_user_blocks(struct f2fs_sb_info *sbi) |
| 47 | { |
| 48 | if (free_segments(sbi) < overprovision_segments(sbi)) |
| 49 | return 0; |
| 50 | else |
| 51 | return (free_segments(sbi) - overprovision_segments(sbi)) |
| 52 | << sbi->log_blocks_per_seg; |
| 53 | } |
| 54 | |
| 55 | static inline block_t limit_invalid_user_blocks(struct f2fs_sb_info *sbi) |
| 56 | { |
| 57 | return (long)(sbi->user_block_count * LIMIT_INVALID_BLOCK) / 100; |
| 58 | } |
| 59 | |
| 60 | static inline block_t limit_free_user_blocks(struct f2fs_sb_info *sbi) |
| 61 | { |
| 62 | block_t reclaimable_user_blocks = sbi->user_block_count - |
| 63 | written_block_count(sbi); |
| 64 | return (long)(reclaimable_user_blocks * LIMIT_FREE_BLOCK) / 100; |
| 65 | } |
| 66 | |
| 67 | static inline void increase_sleep_time(struct f2fs_gc_kthread *gc_th, |
| 68 | long *wait) |
| 69 | { |
| 70 | if (*wait == gc_th->no_gc_sleep_time) |
| 71 | return; |
| 72 | |
| 73 | *wait += gc_th->min_sleep_time; |
| 74 | if (*wait > gc_th->max_sleep_time) |
| 75 | *wait = gc_th->max_sleep_time; |
| 76 | } |
| 77 | |
| 78 | static inline void decrease_sleep_time(struct f2fs_gc_kthread *gc_th, |
| 79 | long *wait) |
| 80 | { |
| 81 | if (*wait == gc_th->no_gc_sleep_time) |
| 82 | *wait = gc_th->max_sleep_time; |
| 83 | |
| 84 | *wait -= gc_th->min_sleep_time; |
| 85 | if (*wait <= gc_th->min_sleep_time) |
| 86 | *wait = gc_th->min_sleep_time; |
| 87 | } |
| 88 | |
| 89 | static inline bool has_enough_invalid_blocks(struct f2fs_sb_info *sbi) |
| 90 | { |
| 91 | block_t invalid_user_blocks = sbi->user_block_count - |
| 92 | written_block_count(sbi); |
| 93 | /* |
| 94 | * Background GC is triggered with the following conditions. |
| 95 | * 1. There are a number of invalid blocks. |
| 96 | * 2. There is not enough free space. |
| 97 | */ |
| 98 | if (invalid_user_blocks > limit_invalid_user_blocks(sbi) && |
| 99 | free_user_blocks(sbi) < limit_free_user_blocks(sbi)) |
| 100 | return true; |
| 101 | return false; |
| 102 | } |
| 103 | |
| 104 | static inline int is_idle(struct f2fs_sb_info *sbi) |
| 105 | { |
| 106 | struct block_device *bdev = sbi->sb->s_bdev; |
| 107 | struct request_queue *q = bdev_get_queue(bdev); |
| 108 | struct request_list *rl = &q->root_rl; |
| 109 | return !(rl->count[BLK_RW_SYNC]) && !(rl->count[BLK_RW_ASYNC]); |
| 110 | } |