Commit | Line | Data |
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2658e50d JK |
1 | /* |
2 | * f2fs shrinker support | |
3 | * the basic infra was copied from fs/ubifs/shrinker.c | |
4 | * | |
5 | * Copyright (c) 2015 Motorola Mobility | |
6 | * Copyright (c) 2015 Jaegeuk Kim <jaegeuk@kernel.org> | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or modify | |
9 | * it under the terms of the GNU General Public License version 2 as | |
10 | * published by the Free Software Foundation. | |
11 | */ | |
12 | #include <linux/fs.h> | |
13 | #include <linux/f2fs_fs.h> | |
14 | ||
15 | #include "f2fs.h" | |
ad4edb83 | 16 | #include "node.h" |
2658e50d JK |
17 | |
18 | static LIST_HEAD(f2fs_list); | |
19 | static DEFINE_SPINLOCK(f2fs_list_lock); | |
20 | static unsigned int shrinker_run_no; | |
21 | ||
1b38dc8e JK |
22 | static unsigned long __count_nat_entries(struct f2fs_sb_info *sbi) |
23 | { | |
24 | return NM_I(sbi)->nat_cnt - NM_I(sbi)->dirty_nat_cnt; | |
25 | } | |
26 | ||
31696580 CY |
27 | static unsigned long __count_free_nids(struct f2fs_sb_info *sbi) |
28 | { | |
ad4edb83 JK |
29 | if (NM_I(sbi)->fcnt > MAX_FREE_NIDS) |
30 | return NM_I(sbi)->fcnt - MAX_FREE_NIDS; | |
31696580 CY |
31 | return 0; |
32 | } | |
33 | ||
554df79e JK |
34 | static unsigned long __count_extent_cache(struct f2fs_sb_info *sbi) |
35 | { | |
74fd8d99 | 36 | return atomic_read(&sbi->total_zombie_tree) + |
7441ccef | 37 | atomic_read(&sbi->total_ext_node); |
554df79e JK |
38 | } |
39 | ||
2658e50d JK |
40 | unsigned long f2fs_shrink_count(struct shrinker *shrink, |
41 | struct shrink_control *sc) | |
42 | { | |
43 | struct f2fs_sb_info *sbi; | |
44 | struct list_head *p; | |
45 | unsigned long count = 0; | |
46 | ||
47 | spin_lock(&f2fs_list_lock); | |
48 | p = f2fs_list.next; | |
49 | while (p != &f2fs_list) { | |
50 | sbi = list_entry(p, struct f2fs_sb_info, s_list); | |
51 | ||
52 | /* stop f2fs_put_super */ | |
53 | if (!mutex_trylock(&sbi->umount_mutex)) { | |
54 | p = p->next; | |
55 | continue; | |
56 | } | |
57 | spin_unlock(&f2fs_list_lock); | |
58 | ||
554df79e JK |
59 | /* count extent cache entries */ |
60 | count += __count_extent_cache(sbi); | |
61 | ||
1b38dc8e JK |
62 | /* shrink clean nat cache entries */ |
63 | count += __count_nat_entries(sbi); | |
2658e50d | 64 | |
31696580 CY |
65 | /* count free nids cache entries */ |
66 | count += __count_free_nids(sbi); | |
67 | ||
2658e50d JK |
68 | spin_lock(&f2fs_list_lock); |
69 | p = p->next; | |
70 | mutex_unlock(&sbi->umount_mutex); | |
71 | } | |
72 | spin_unlock(&f2fs_list_lock); | |
73 | return count; | |
74 | } | |
75 | ||
76 | unsigned long f2fs_shrink_scan(struct shrinker *shrink, | |
77 | struct shrink_control *sc) | |
78 | { | |
79 | unsigned long nr = sc->nr_to_scan; | |
80 | struct f2fs_sb_info *sbi; | |
81 | struct list_head *p; | |
82 | unsigned int run_no; | |
83 | unsigned long freed = 0; | |
84 | ||
85 | spin_lock(&f2fs_list_lock); | |
86 | do { | |
87 | run_no = ++shrinker_run_no; | |
88 | } while (run_no == 0); | |
89 | p = f2fs_list.next; | |
90 | while (p != &f2fs_list) { | |
91 | sbi = list_entry(p, struct f2fs_sb_info, s_list); | |
92 | ||
93 | if (sbi->shrinker_run_no == run_no) | |
94 | break; | |
95 | ||
96 | /* stop f2fs_put_super */ | |
97 | if (!mutex_trylock(&sbi->umount_mutex)) { | |
98 | p = p->next; | |
99 | continue; | |
100 | } | |
101 | spin_unlock(&f2fs_list_lock); | |
102 | ||
103 | sbi->shrinker_run_no = run_no; | |
104 | ||
554df79e JK |
105 | /* shrink extent cache entries */ |
106 | freed += f2fs_shrink_extent_tree(sbi, nr >> 1); | |
107 | ||
1b38dc8e | 108 | /* shrink clean nat cache entries */ |
554df79e JK |
109 | if (freed < nr) |
110 | freed += try_to_free_nats(sbi, nr - freed); | |
2658e50d | 111 | |
31696580 CY |
112 | /* shrink free nids cache entries */ |
113 | if (freed < nr) | |
114 | freed += try_to_free_nids(sbi, nr - freed); | |
115 | ||
2658e50d JK |
116 | spin_lock(&f2fs_list_lock); |
117 | p = p->next; | |
118 | list_move_tail(&sbi->s_list, &f2fs_list); | |
119 | mutex_unlock(&sbi->umount_mutex); | |
120 | if (freed >= nr) | |
121 | break; | |
122 | } | |
123 | spin_unlock(&f2fs_list_lock); | |
124 | return freed; | |
125 | } | |
126 | ||
127 | void f2fs_join_shrinker(struct f2fs_sb_info *sbi) | |
128 | { | |
129 | spin_lock(&f2fs_list_lock); | |
130 | list_add_tail(&sbi->s_list, &f2fs_list); | |
131 | spin_unlock(&f2fs_list_lock); | |
132 | } | |
133 | ||
134 | void f2fs_leave_shrinker(struct f2fs_sb_info *sbi) | |
135 | { | |
3e72f721 JK |
136 | f2fs_shrink_extent_tree(sbi, __count_extent_cache(sbi)); |
137 | ||
2658e50d JK |
138 | spin_lock(&f2fs_list_lock); |
139 | list_del(&sbi->s_list); | |
140 | spin_unlock(&f2fs_list_lock); | |
141 | } |