projects / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 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 <[email protected]> | |
| 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" | |
| 16 | ||
| 17 | static LIST_HEAD(f2fs_list); | |
| 18 | static DEFINE_SPINLOCK(f2fs_list_lock); | |
| 19 | static unsigned int shrinker_run_no; | |
| 20 | ||
| 1b38dc8e JK |
21 | static unsigned long __count_nat_entries(struct f2fs_sb_info *sbi) |
| 22 | { | |
| 23 | return NM_I(sbi)->nat_cnt - NM_I(sbi)->dirty_nat_cnt; | |
| 24 | } | |
| 25 | ||
| 31696580 CY |
26 | static unsigned long __count_free_nids(struct f2fs_sb_info *sbi) |
| 27 | { | |
| 28 | if (NM_I(sbi)->fcnt > NAT_ENTRY_PER_BLOCK) | |
| 29 | return NM_I(sbi)->fcnt - NAT_ENTRY_PER_BLOCK; | |
| 30 | return 0; | |
| 31 | } | |
| 32 | ||
| 554df79e JK |
33 | static unsigned long __count_extent_cache(struct f2fs_sb_info *sbi) |
| 34 | { | |
| 35 | return sbi->total_ext_tree + atomic_read(&sbi->total_ext_node); | |
| 36 | } | |
| 37 | ||
| 2658e50d JK |
38 | unsigned long f2fs_shrink_count(struct shrinker *shrink, |
| 39 | struct shrink_control *sc) | |
| 40 | { | |
| 41 | struct f2fs_sb_info *sbi; | |
| 42 | struct list_head *p; | |
| 43 | unsigned long count = 0; | |
| 44 | ||
| 45 | spin_lock(&f2fs_list_lock); | |
| 46 | p = f2fs_list.next; | |
| 47 | while (p != &f2fs_list) { | |
| 48 | sbi = list_entry(p, struct f2fs_sb_info, s_list); | |
| 49 | ||
| 50 | /* stop f2fs_put_super */ | |
| 51 | if (!mutex_trylock(&sbi->umount_mutex)) { | |
| 52 | p = p->next; | |
| 53 | continue; | |
| 54 | } | |
| 55 | spin_unlock(&f2fs_list_lock); | |
| 56 | ||
| 554df79e JK |
57 | /* count extent cache entries */ |
| 58 | count += __count_extent_cache(sbi); | |
| 59 | ||
| 1b38dc8e JK |
60 | /* shrink clean nat cache entries */ |
| 61 | count += __count_nat_entries(sbi); | |
| 2658e50d | 62 | |
| 31696580 CY |
63 | /* count free nids cache entries */ |
| 64 | count += __count_free_nids(sbi); | |
| 65 | ||
| 2658e50d JK |
66 | spin_lock(&f2fs_list_lock); |
| 67 | p = p->next; | |
| 68 | mutex_unlock(&sbi->umount_mutex); | |
| 69 | } | |
| 70 | spin_unlock(&f2fs_list_lock); | |
| 71 | return count; | |
| 72 | } | |
| 73 | ||
| 74 | unsigned long f2fs_shrink_scan(struct shrinker *shrink, | |
| 75 | struct shrink_control *sc) | |
| 76 | { | |
| 77 | unsigned long nr = sc->nr_to_scan; | |
| 78 | struct f2fs_sb_info *sbi; | |
| 79 | struct list_head *p; | |
| 80 | unsigned int run_no; | |
| 81 | unsigned long freed = 0; | |
| 82 | ||
| 83 | spin_lock(&f2fs_list_lock); | |
| 84 | do { | |
| 85 | run_no = ++shrinker_run_no; | |
| 86 | } while (run_no == 0); | |
| 87 | p = f2fs_list.next; | |
| 88 | while (p != &f2fs_list) { | |
| 89 | sbi = list_entry(p, struct f2fs_sb_info, s_list); | |
| 90 | ||
| 91 | if (sbi->shrinker_run_no == run_no) | |
| 92 | break; | |
| 93 | ||
| 94 | /* stop f2fs_put_super */ | |
| 95 | if (!mutex_trylock(&sbi->umount_mutex)) { | |
| 96 | p = p->next; | |
| 97 | continue; | |
| 98 | } | |
| 99 | spin_unlock(&f2fs_list_lock); | |
| 100 | ||
| 101 | sbi->shrinker_run_no = run_no; | |
| 102 | ||
| 554df79e JK |
103 | /* shrink extent cache entries */ |
| 104 | freed += f2fs_shrink_extent_tree(sbi, nr >> 1); | |
| 105 | ||
| 1b38dc8e | 106 | /* shrink clean nat cache entries */ |
| 554df79e JK |
107 | if (freed < nr) |
| 108 | freed += try_to_free_nats(sbi, nr - freed); | |
| 2658e50d | 109 | |
| 31696580 CY |
110 | /* shrink free nids cache entries */ |
| 111 | if (freed < nr) | |
| 112 | freed += try_to_free_nids(sbi, nr - freed); | |
| 113 | ||
| 2658e50d JK |
114 | spin_lock(&f2fs_list_lock); |
| 115 | p = p->next; | |
| 116 | list_move_tail(&sbi->s_list, &f2fs_list); | |
| 117 | mutex_unlock(&sbi->umount_mutex); | |
| 118 | if (freed >= nr) | |
| 119 | break; | |
| 120 | } | |
| 121 | spin_unlock(&f2fs_list_lock); | |
| 122 | return freed; | |
| 123 | } | |
| 124 | ||
| 125 | void f2fs_join_shrinker(struct f2fs_sb_info *sbi) | |
| 126 | { | |
| 127 | spin_lock(&f2fs_list_lock); | |
| 128 | list_add_tail(&sbi->s_list, &f2fs_list); | |
| 129 | spin_unlock(&f2fs_list_lock); | |
| 130 | } | |
| 131 | ||
| 132 | void f2fs_leave_shrinker(struct f2fs_sb_info *sbi) | |
| 133 | { | |
| 3e72f721 JK |
134 | f2fs_shrink_extent_tree(sbi, __count_extent_cache(sbi)); |
| 135 | ||
| 2658e50d JK |
136 | spin_lock(&f2fs_list_lock); |
| 137 | list_del(&sbi->s_list); | |
| 138 | spin_unlock(&f2fs_list_lock); | |
| 139 | } |