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 */
free_segs_blk_count_zoned(struct f2fs_sb_info * sbi)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(&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, j);
89 spin_unlock(&free_i->segmap_lock);
90
91 return free_seg_blks;
92 }
93
free_segs_blk_count(struct f2fs_sb_info * sbi)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 free_segments(sbi) << sbi->log_blocks_per_seg;
100 }
101
free_user_blocks(struct f2fs_sb_info * sbi)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 = overprovision_segments(sbi) << sbi->log_blocks_per_seg;
108
109 if (free_blks < ovp_blks)
110 return 0;
111
112 return free_blks - ovp_blks;
113 }
114
limit_invalid_user_blocks(block_t user_block_count)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
limit_free_user_blocks(block_t reclaimable_user_blocks)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
increase_sleep_time(struct f2fs_gc_kthread * gc_th,unsigned int * wait)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
decrease_sleep_time(struct f2fs_gc_kthread * gc_th,unsigned int * wait)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
has_enough_invalid_blocks(struct f2fs_sb_info * sbi)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(invalid_user_blocks));
168 }
169