xref: /linux/fs/f2fs/gc.h (revision 0974f486f3dde9df1ad979d4ff341dc9c2d545f5)
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 /* GC sleep parameters for zoned deivces */
19 #define DEF_GC_THREAD_MIN_SLEEP_TIME_ZONED	10
20 #define DEF_GC_THREAD_MAX_SLEEP_TIME_ZONED	20
21 #define DEF_GC_THREAD_NOGC_SLEEP_TIME_ZONED	60000
22 
23 /* choose candidates from sections which has age of more than 7 days */
24 #define DEF_GC_THREAD_AGE_THRESHOLD		(60 * 60 * 24 * 7)
25 #define DEF_GC_THREAD_CANDIDATE_RATIO		20	/* select 20% oldest sections as candidates */
26 #define DEF_GC_THREAD_MAX_CANDIDATE_COUNT	10	/* select at most 10 sections as candidates */
27 #define DEF_GC_THREAD_AGE_WEIGHT		60	/* age weight */
28 #define DEF_GC_THREAD_VALID_THRESH_RATIO	95	/* do not GC over 95% valid block ratio for one time GC */
29 #define DEFAULT_ACCURACY_CLASS			10000	/* accuracy class */
30 
31 #define LIMIT_INVALID_BLOCK	40 /* percentage over total user space */
32 #define LIMIT_FREE_BLOCK	40 /* percentage over invalid + free space */
33 
34 #define LIMIT_NO_ZONED_GC	60 /* percentage over total user space of no gc for zoned devices */
35 #define LIMIT_BOOST_ZONED_GC	25 /* percentage over total user space of boosted gc for zoned devices */
36 #define DEF_MIGRATION_WINDOW_GRANULARITY_ZONED	3
37 #define BOOST_GC_MULTIPLE	5
38 #define ZONED_PIN_SEC_REQUIRED_COUNT	1
39 
40 #define DEF_GC_FAILED_PINNED_FILES	2048
41 #define MAX_GC_FAILED_PINNED_FILES	USHRT_MAX
42 
43 /* Search max. number of dirty segments to select a victim segment */
44 #define DEF_MAX_VICTIM_SEARCH 4096 /* covers 8GB */
45 
46 #define NR_GC_CHECKPOINT_SECS (3)	/* data/node/dentry sections */
47 
48 struct f2fs_gc_kthread {
49 	struct task_struct *f2fs_gc_task;
50 	wait_queue_head_t gc_wait_queue_head;
51 
52 	/* for gc sleep time */
53 	unsigned int urgent_sleep_time;
54 	unsigned int min_sleep_time;
55 	unsigned int max_sleep_time;
56 	unsigned int no_gc_sleep_time;
57 
58 	/* for changing gc mode */
59 	bool gc_wake;
60 
61 	/* for GC_MERGE mount option */
62 	wait_queue_head_t fggc_wq;		/*
63 						 * caller of f2fs_balance_fs()
64 						 * will wait on this wait queue.
65 						 */
66 
67 	/* for gc control for zoned devices */
68 	unsigned int no_zoned_gc_percent;
69 	unsigned int boost_zoned_gc_percent;
70 	unsigned int valid_thresh_ratio;
71 	unsigned int boost_gc_multiple;
72 	unsigned int boost_gc_greedy;
73 };
74 
75 struct gc_inode_list {
76 	struct list_head ilist;
77 	struct radix_tree_root iroot;
78 };
79 
80 struct victim_entry {
81 	struct rb_node rb_node;		/* rb node located in rb-tree */
82 	unsigned long long mtime;	/* mtime of section */
83 	unsigned int segno;		/* segment No. */
84 	struct list_head list;
85 };
86 
87 /*
88  * inline functions
89  */
90 
91 /*
92  * On a Zoned device zone-capacity can be less than zone-size and if
93  * zone-capacity is not aligned to f2fs segment size(2MB), then the segment
94  * starting just before zone-capacity has some blocks spanning across the
95  * zone-capacity, these blocks are not usable.
96  * Such spanning segments can be in free list so calculate the sum of usable
97  * blocks in currently free segments including normal and spanning segments.
98  */
free_segs_blk_count_zoned(struct f2fs_sb_info * sbi)99 static inline block_t free_segs_blk_count_zoned(struct f2fs_sb_info *sbi)
100 {
101 	block_t free_seg_blks = 0;
102 	struct free_segmap_info *free_i = FREE_I(sbi);
103 	int j;
104 
105 	spin_lock(&free_i->segmap_lock);
106 	for (j = 0; j < MAIN_SEGS(sbi); j++)
107 		if (!test_bit(j, free_i->free_segmap))
108 			free_seg_blks += f2fs_usable_blks_in_seg(sbi, j);
109 	spin_unlock(&free_i->segmap_lock);
110 
111 	return free_seg_blks;
112 }
113 
free_segs_blk_count(struct f2fs_sb_info * sbi)114 static inline block_t free_segs_blk_count(struct f2fs_sb_info *sbi)
115 {
116 	if (f2fs_sb_has_blkzoned(sbi))
117 		return free_segs_blk_count_zoned(sbi);
118 
119 	return SEGS_TO_BLKS(sbi, free_segments(sbi));
120 }
121 
free_user_blocks(struct f2fs_sb_info * sbi)122 static inline block_t free_user_blocks(struct f2fs_sb_info *sbi)
123 {
124 	block_t free_blks, ovp_blks;
125 
126 	free_blks = free_segs_blk_count(sbi);
127 	ovp_blks = SEGS_TO_BLKS(sbi, overprovision_segments(sbi));
128 
129 	if (free_blks < ovp_blks)
130 		return 0;
131 
132 	return free_blks - ovp_blks;
133 }
134 
limit_invalid_user_blocks(block_t user_block_count)135 static inline block_t limit_invalid_user_blocks(block_t user_block_count)
136 {
137 	return (long)(user_block_count * LIMIT_INVALID_BLOCK) / 100;
138 }
139 
limit_free_user_blocks(block_t reclaimable_user_blocks)140 static inline block_t limit_free_user_blocks(block_t reclaimable_user_blocks)
141 {
142 	return (long)(reclaimable_user_blocks * LIMIT_FREE_BLOCK) / 100;
143 }
144 
increase_sleep_time(struct f2fs_gc_kthread * gc_th,unsigned int * wait)145 static inline void increase_sleep_time(struct f2fs_gc_kthread *gc_th,
146 							unsigned int *wait)
147 {
148 	unsigned int min_time = gc_th->min_sleep_time;
149 	unsigned int max_time = gc_th->max_sleep_time;
150 
151 	if (*wait == gc_th->no_gc_sleep_time)
152 		return;
153 
154 	if ((long long)*wait + (long long)min_time > (long long)max_time)
155 		*wait = max_time;
156 	else
157 		*wait += min_time;
158 }
159 
decrease_sleep_time(struct f2fs_gc_kthread * gc_th,unsigned int * wait)160 static inline void decrease_sleep_time(struct f2fs_gc_kthread *gc_th,
161 							unsigned int *wait)
162 {
163 	unsigned int min_time = gc_th->min_sleep_time;
164 
165 	if (*wait == gc_th->no_gc_sleep_time)
166 		*wait = gc_th->max_sleep_time;
167 
168 	if ((long long)*wait - (long long)min_time < (long long)min_time)
169 		*wait = min_time;
170 	else
171 		*wait -= min_time;
172 }
173 
has_enough_free_blocks(struct f2fs_sb_info * sbi,unsigned int limit_perc)174 static inline bool has_enough_free_blocks(struct f2fs_sb_info *sbi,
175 						unsigned int limit_perc)
176 {
177 	return free_sections(sbi) > ((sbi->total_sections * limit_perc) / 100);
178 }
179 
has_enough_invalid_blocks(struct f2fs_sb_info * sbi)180 static inline bool has_enough_invalid_blocks(struct f2fs_sb_info *sbi)
181 {
182 	block_t user_block_count = sbi->user_block_count;
183 	block_t invalid_user_blocks = user_block_count -
184 		written_block_count(sbi);
185 	/*
186 	 * Background GC is triggered with the following conditions.
187 	 * 1. There are a number of invalid blocks.
188 	 * 2. There is not enough free space.
189 	 */
190 	return (invalid_user_blocks >
191 			limit_invalid_user_blocks(user_block_count) &&
192 		free_user_blocks(sbi) <
193 			limit_free_user_blocks(invalid_user_blocks));
194 }
195 
need_to_boost_gc(struct f2fs_sb_info * sbi)196 static inline bool need_to_boost_gc(struct f2fs_sb_info *sbi)
197 {
198 	if (f2fs_sb_has_blkzoned(sbi))
199 		return !has_enough_free_blocks(sbi,
200 				sbi->gc_thread->boost_zoned_gc_percent);
201 	return has_enough_invalid_blocks(sbi);
202 }
203