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 | |
30 | /* Search max. number of dirty segments to select a victim segment */ |
31 | #define DEF_MAX_VICTIM_SEARCH 4096 /* covers 8GB */ |
32 | |
33 | #define NR_GC_CHECKPOINT_SECS (3) /* data/node/dentry sections */ |
34 | |
35 | struct f2fs_gc_kthread { |
36 | struct task_struct *f2fs_gc_task; |
37 | wait_queue_head_t gc_wait_queue_head; |
38 | |
39 | /* for gc sleep time */ |
40 | unsigned int urgent_sleep_time; |
41 | unsigned int min_sleep_time; |
42 | unsigned int max_sleep_time; |
43 | unsigned int no_gc_sleep_time; |
44 | |
45 | /* for changing gc mode */ |
46 | bool gc_wake; |
47 | |
48 | /* for GC_MERGE mount option */ |
49 | wait_queue_head_t fggc_wq; /* |
50 | * caller of f2fs_balance_fs() |
51 | * will wait on this wait queue. |
52 | */ |
53 | }; |
54 | |
55 | struct gc_inode_list { |
56 | struct list_head ilist; |
57 | struct radix_tree_root iroot; |
58 | }; |
59 | |
60 | struct victim_entry { |
61 | struct rb_node rb_node; /* rb node located in rb-tree */ |
62 | unsigned long long mtime; /* mtime of section */ |
63 | unsigned int segno; /* segment No. */ |
64 | struct list_head list; |
65 | }; |
66 | |
67 | /* |
68 | * inline functions |
69 | */ |
70 | |
71 | /* |
72 | * On a Zoned device zone-capacity can be less than zone-size and if |
73 | * zone-capacity is not aligned to f2fs segment size(2MB), then the segment |
74 | * starting just before zone-capacity has some blocks spanning across the |
75 | * zone-capacity, these blocks are not usable. |
76 | * Such spanning segments can be in free list so calculate the sum of usable |
77 | * blocks in currently free segments including normal and spanning segments. |
78 | */ |
79 | static inline block_t free_segs_blk_count_zoned(struct f2fs_sb_info *sbi) |
80 | { |
81 | block_t free_seg_blks = 0; |
82 | struct free_segmap_info *free_i = FREE_I(sbi); |
83 | int j; |
84 | |
85 | spin_lock(lock: &free_i->segmap_lock); |
86 | for (j = 0; j < MAIN_SEGS(sbi); j++) |
87 | if (!test_bit(j, free_i->free_segmap)) |
88 | free_seg_blks += f2fs_usable_blks_in_seg(sbi, segno: j); |
89 | spin_unlock(lock: &free_i->segmap_lock); |
90 | |
91 | return free_seg_blks; |
92 | } |
93 | |
94 | static inline block_t free_segs_blk_count(struct f2fs_sb_info *sbi) |
95 | { |
96 | if (f2fs_sb_has_blkzoned(sbi)) |
97 | return free_segs_blk_count_zoned(sbi); |
98 | |
99 | return SEGS_TO_BLKS(sbi, free_segments(sbi)); |
100 | } |
101 | |
102 | static inline block_t free_user_blocks(struct f2fs_sb_info *sbi) |
103 | { |
104 | block_t free_blks, ovp_blks; |
105 | |
106 | free_blks = free_segs_blk_count(sbi); |
107 | ovp_blks = SEGS_TO_BLKS(sbi, overprovision_segments(sbi)); |
108 | |
109 | if (free_blks < ovp_blks) |
110 | return 0; |
111 | |
112 | return free_blks - ovp_blks; |
113 | } |
114 | |
115 | static inline block_t limit_invalid_user_blocks(block_t user_block_count) |
116 | { |
117 | return (long)(user_block_count * LIMIT_INVALID_BLOCK) / 100; |
118 | } |
119 | |
120 | static inline block_t limit_free_user_blocks(block_t reclaimable_user_blocks) |
121 | { |
122 | return (long)(reclaimable_user_blocks * LIMIT_FREE_BLOCK) / 100; |
123 | } |
124 | |
125 | static inline void increase_sleep_time(struct f2fs_gc_kthread *gc_th, |
126 | unsigned int *wait) |
127 | { |
128 | unsigned int min_time = gc_th->min_sleep_time; |
129 | unsigned int max_time = gc_th->max_sleep_time; |
130 | |
131 | if (*wait == gc_th->no_gc_sleep_time) |
132 | return; |
133 | |
134 | if ((long long)*wait + (long long)min_time > (long long)max_time) |
135 | *wait = max_time; |
136 | else |
137 | *wait += min_time; |
138 | } |
139 | |
140 | static inline void decrease_sleep_time(struct f2fs_gc_kthread *gc_th, |
141 | unsigned int *wait) |
142 | { |
143 | unsigned int min_time = gc_th->min_sleep_time; |
144 | |
145 | if (*wait == gc_th->no_gc_sleep_time) |
146 | *wait = gc_th->max_sleep_time; |
147 | |
148 | if ((long long)*wait - (long long)min_time < (long long)min_time) |
149 | *wait = min_time; |
150 | else |
151 | *wait -= min_time; |
152 | } |
153 | |
154 | static inline bool has_enough_invalid_blocks(struct f2fs_sb_info *sbi) |
155 | { |
156 | block_t user_block_count = sbi->user_block_count; |
157 | block_t invalid_user_blocks = user_block_count - |
158 | written_block_count(sbi); |
159 | /* |
160 | * Background GC is triggered with the following conditions. |
161 | * 1. There are a number of invalid blocks. |
162 | * 2. There is not enough free space. |
163 | */ |
164 | return (invalid_user_blocks > |
165 | limit_invalid_user_blocks(user_block_count) && |
166 | free_user_blocks(sbi) < |
167 | limit_free_user_blocks(reclaimable_user_blocks: invalid_user_blocks)); |
168 | } |
169 | |