1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * fs/f2fs/gc.h 4 * 5 * Copyright (c) 2012 Samsung Electronics Co., Ltd. 6 * http://www.samsung.com/ 7 */ 8 #define GC_THREAD_MIN_WB_PAGES 1 /* 9 * a threshold to determine 10 * whether IO subsystem is idle 11 * or not 12 */ 13 #define DEF_GC_THREAD_URGENT_SLEEP_TIME 500 /* 500 ms */ 14 #define DEF_GC_THREAD_MIN_SLEEP_TIME 30000 /* milliseconds */ 15 #define DEF_GC_THREAD_MAX_SLEEP_TIME 60000 16 #define DEF_GC_THREAD_NOGC_SLEEP_TIME 300000 /* wait 5 min */ 17 18 /* choose candidates from sections which has age of more than 7 days */ 19 #define DEF_GC_THREAD_AGE_THRESHOLD (60 * 60 * 24 * 7) 20 #define DEF_GC_THREAD_CANDIDATE_RATIO 20 /* select 20% oldest sections as candidates */ 21 #define DEF_GC_THREAD_MAX_CANDIDATE_COUNT 10 /* select at most 10 sections as candidates */ 22 #define DEF_GC_THREAD_AGE_WEIGHT 60 /* age weight */ 23 #define DEFAULT_ACCURACY_CLASS 10000 /* accuracy class */ 24 25 #define LIMIT_INVALID_BLOCK 40 /* percentage over total user space */ 26 #define LIMIT_FREE_BLOCK 40 /* percentage over invalid + free space */ 27 28 #define DEF_GC_FAILED_PINNED_FILES 2048 29 #define MAX_GC_FAILED_PINNED_FILES USHRT_MAX 30 31 /* Search max. number of dirty segments to select a victim segment */ 32 #define DEF_MAX_VICTIM_SEARCH 4096 /* covers 8GB */ 33 34 #define NR_GC_CHECKPOINT_SECS (3) /* data/node/dentry sections */ 35 36 struct f2fs_gc_kthread { 37 struct task_struct *f2fs_gc_task; 38 wait_queue_head_t gc_wait_queue_head; 39 40 /* for gc sleep time */ 41 unsigned int urgent_sleep_time; 42 unsigned int min_sleep_time; 43 unsigned int max_sleep_time; 44 unsigned int no_gc_sleep_time; 45 46 /* for changing gc mode */ 47 bool gc_wake; 48 49 /* for GC_MERGE mount option */ 50 wait_queue_head_t fggc_wq; /* 51 * caller of f2fs_balance_fs() 52 * will wait on this wait queue. 53 */ 54 }; 55 56 struct gc_inode_list { 57 struct list_head ilist; 58 struct radix_tree_root iroot; 59 }; 60 61 struct victim_entry { 62 struct rb_node rb_node; /* rb node located in rb-tree */ 63 unsigned long long mtime; /* mtime of section */ 64 unsigned int segno; /* segment No. */ 65 struct list_head list; 66 }; 67 68 /* 69 * inline functions 70 */ 71 72 /* 73 * On a Zoned device zone-capacity can be less than zone-size and if 74 * zone-capacity is not aligned to f2fs segment size(2MB), then the segment 75 * starting just before zone-capacity has some blocks spanning across the 76 * zone-capacity, these blocks are not usable. 77 * Such spanning segments can be in free list so calculate the sum of usable 78 * blocks in currently free segments including normal and spanning segments. 79 */ 80 static inline block_t free_segs_blk_count_zoned(struct f2fs_sb_info *sbi) 81 { 82 block_t free_seg_blks = 0; 83 struct free_segmap_info *free_i = FREE_I(sbi); 84 int j; 85 86 spin_lock(&free_i->segmap_lock); 87 for (j = 0; j < MAIN_SEGS(sbi); j++) 88 if (!test_bit(j, free_i->free_segmap)) 89 free_seg_blks += f2fs_usable_blks_in_seg(sbi, j); 90 spin_unlock(&free_i->segmap_lock); 91 92 return free_seg_blks; 93 } 94 95 static inline block_t free_segs_blk_count(struct f2fs_sb_info *sbi) 96 { 97 if (f2fs_sb_has_blkzoned(sbi)) 98 return free_segs_blk_count_zoned(sbi); 99 100 return SEGS_TO_BLKS(sbi, free_segments(sbi)); 101 } 102 103 static inline block_t free_user_blocks(struct f2fs_sb_info *sbi) 104 { 105 block_t free_blks, ovp_blks; 106 107 free_blks = free_segs_blk_count(sbi); 108 ovp_blks = SEGS_TO_BLKS(sbi, overprovision_segments(sbi)); 109 110 if (free_blks < ovp_blks) 111 return 0; 112 113 return free_blks - ovp_blks; 114 } 115 116 static inline block_t limit_invalid_user_blocks(block_t user_block_count) 117 { 118 return (long)(user_block_count * LIMIT_INVALID_BLOCK) / 100; 119 } 120 121 static inline block_t limit_free_user_blocks(block_t reclaimable_user_blocks) 122 { 123 return (long)(reclaimable_user_blocks * LIMIT_FREE_BLOCK) / 100; 124 } 125 126 static inline void increase_sleep_time(struct f2fs_gc_kthread *gc_th, 127 unsigned int *wait) 128 { 129 unsigned int min_time = gc_th->min_sleep_time; 130 unsigned int max_time = gc_th->max_sleep_time; 131 132 if (*wait == gc_th->no_gc_sleep_time) 133 return; 134 135 if ((long long)*wait + (long long)min_time > (long long)max_time) 136 *wait = max_time; 137 else 138 *wait += min_time; 139 } 140 141 static inline void decrease_sleep_time(struct f2fs_gc_kthread *gc_th, 142 unsigned int *wait) 143 { 144 unsigned int min_time = gc_th->min_sleep_time; 145 146 if (*wait == gc_th->no_gc_sleep_time) 147 *wait = gc_th->max_sleep_time; 148 149 if ((long long)*wait - (long long)min_time < (long long)min_time) 150 *wait = min_time; 151 else 152 *wait -= min_time; 153 } 154 155 static inline bool has_enough_invalid_blocks(struct f2fs_sb_info *sbi) 156 { 157 block_t user_block_count = sbi->user_block_count; 158 block_t invalid_user_blocks = user_block_count - 159 written_block_count(sbi); 160 /* 161 * Background GC is triggered with the following conditions. 162 * 1. There are a number of invalid blocks. 163 * 2. There is not enough free space. 164 */ 165 return (invalid_user_blocks > 166 limit_invalid_user_blocks(user_block_count) && 167 free_user_blocks(sbi) < 168 limit_free_user_blocks(invalid_user_blocks)); 169 } 170