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Merge branch 'for-linus' into for-4.12/block
[karo-tx-linux.git] / fs / f2fs / debug.c
1 /*
2  * f2fs debugging statistics
3  *
4  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
5  *             http://www.samsung.com/
6  * Copyright (c) 2012 Linux Foundation
7  * Copyright (c) 2012 Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  */
13
14 #include <linux/fs.h>
15 #include <linux/backing-dev.h>
16 #include <linux/f2fs_fs.h>
17 #include <linux/blkdev.h>
18 #include <linux/debugfs.h>
19 #include <linux/seq_file.h>
20
21 #include "f2fs.h"
22 #include "node.h"
23 #include "segment.h"
24 #include "gc.h"
25
26 static LIST_HEAD(f2fs_stat_list);
27 static struct dentry *f2fs_debugfs_root;
28 static DEFINE_MUTEX(f2fs_stat_mutex);
29
30 static void update_general_status(struct f2fs_sb_info *sbi)
31 {
32         struct f2fs_stat_info *si = F2FS_STAT(sbi);
33         int i;
34
35         /* validation check of the segment numbers */
36         si->hit_largest = atomic64_read(&sbi->read_hit_largest);
37         si->hit_cached = atomic64_read(&sbi->read_hit_cached);
38         si->hit_rbtree = atomic64_read(&sbi->read_hit_rbtree);
39         si->hit_total = si->hit_largest + si->hit_cached + si->hit_rbtree;
40         si->total_ext = atomic64_read(&sbi->total_hit_ext);
41         si->ext_tree = atomic_read(&sbi->total_ext_tree);
42         si->zombie_tree = atomic_read(&sbi->total_zombie_tree);
43         si->ext_node = atomic_read(&sbi->total_ext_node);
44         si->ndirty_node = get_pages(sbi, F2FS_DIRTY_NODES);
45         si->ndirty_dent = get_pages(sbi, F2FS_DIRTY_DENTS);
46         si->ndirty_meta = get_pages(sbi, F2FS_DIRTY_META);
47         si->ndirty_data = get_pages(sbi, F2FS_DIRTY_DATA);
48         si->ndirty_imeta = get_pages(sbi, F2FS_DIRTY_IMETA);
49         si->ndirty_dirs = sbi->ndirty_inode[DIR_INODE];
50         si->ndirty_files = sbi->ndirty_inode[FILE_INODE];
51         si->ndirty_all = sbi->ndirty_inode[DIRTY_META];
52         si->inmem_pages = get_pages(sbi, F2FS_INMEM_PAGES);
53         si->aw_cnt = atomic_read(&sbi->aw_cnt);
54         si->max_aw_cnt = atomic_read(&sbi->max_aw_cnt);
55         si->nr_wb_cp_data = get_pages(sbi, F2FS_WB_CP_DATA);
56         si->nr_wb_data = get_pages(sbi, F2FS_WB_DATA);
57         if (SM_I(sbi) && SM_I(sbi)->fcc_info)
58                 si->nr_flush =
59                         atomic_read(&SM_I(sbi)->fcc_info->submit_flush);
60         if (SM_I(sbi) && SM_I(sbi)->dcc_info)
61                 si->nr_discard =
62                         atomic_read(&SM_I(sbi)->dcc_info->submit_discard);
63         si->total_count = (int)sbi->user_block_count / sbi->blocks_per_seg;
64         si->rsvd_segs = reserved_segments(sbi);
65         si->overp_segs = overprovision_segments(sbi);
66         si->valid_count = valid_user_blocks(sbi);
67         si->discard_blks = discard_blocks(sbi);
68         si->valid_node_count = valid_node_count(sbi);
69         si->valid_inode_count = valid_inode_count(sbi);
70         si->inline_xattr = atomic_read(&sbi->inline_xattr);
71         si->inline_inode = atomic_read(&sbi->inline_inode);
72         si->inline_dir = atomic_read(&sbi->inline_dir);
73         si->append = sbi->im[APPEND_INO].ino_num;
74         si->update = sbi->im[UPDATE_INO].ino_num;
75         si->orphans = sbi->im[ORPHAN_INO].ino_num;
76         si->utilization = utilization(sbi);
77
78         si->free_segs = free_segments(sbi);
79         si->free_secs = free_sections(sbi);
80         si->prefree_count = prefree_segments(sbi);
81         si->dirty_count = dirty_segments(sbi);
82         si->node_pages = NODE_MAPPING(sbi)->nrpages;
83         si->meta_pages = META_MAPPING(sbi)->nrpages;
84         si->nats = NM_I(sbi)->nat_cnt;
85         si->dirty_nats = NM_I(sbi)->dirty_nat_cnt;
86         si->sits = MAIN_SEGS(sbi);
87         si->dirty_sits = SIT_I(sbi)->dirty_sentries;
88         si->free_nids = NM_I(sbi)->nid_cnt[FREE_NID_LIST];
89         si->alloc_nids = NM_I(sbi)->nid_cnt[ALLOC_NID_LIST];
90         si->bg_gc = sbi->bg_gc;
91         si->util_free = (int)(free_user_blocks(sbi) >> sbi->log_blocks_per_seg)
92                 * 100 / (int)(sbi->user_block_count >> sbi->log_blocks_per_seg)
93                 / 2;
94         si->util_valid = (int)(written_block_count(sbi) >>
95                                                 sbi->log_blocks_per_seg)
96                 * 100 / (int)(sbi->user_block_count >> sbi->log_blocks_per_seg)
97                 / 2;
98         si->util_invalid = 50 - si->util_free - si->util_valid;
99         for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_NODE; i++) {
100                 struct curseg_info *curseg = CURSEG_I(sbi, i);
101                 si->curseg[i] = curseg->segno;
102                 si->cursec[i] = curseg->segno / sbi->segs_per_sec;
103                 si->curzone[i] = si->cursec[i] / sbi->secs_per_zone;
104         }
105
106         for (i = 0; i < 2; i++) {
107                 si->segment_count[i] = sbi->segment_count[i];
108                 si->block_count[i] = sbi->block_count[i];
109         }
110
111         si->inplace_count = atomic_read(&sbi->inplace_count);
112 }
113
114 /*
115  * This function calculates BDF of every segments
116  */
117 static void update_sit_info(struct f2fs_sb_info *sbi)
118 {
119         struct f2fs_stat_info *si = F2FS_STAT(sbi);
120         unsigned long long blks_per_sec, hblks_per_sec, total_vblocks;
121         unsigned long long bimodal, dist;
122         unsigned int segno, vblocks;
123         int ndirty = 0;
124
125         bimodal = 0;
126         total_vblocks = 0;
127         blks_per_sec = sbi->segs_per_sec * sbi->blocks_per_seg;
128         hblks_per_sec = blks_per_sec / 2;
129         for (segno = 0; segno < MAIN_SEGS(sbi); segno += sbi->segs_per_sec) {
130                 vblocks = get_valid_blocks(sbi, segno, sbi->segs_per_sec);
131                 dist = abs(vblocks - hblks_per_sec);
132                 bimodal += dist * dist;
133
134                 if (vblocks > 0 && vblocks < blks_per_sec) {
135                         total_vblocks += vblocks;
136                         ndirty++;
137                 }
138         }
139         dist = div_u64(MAIN_SECS(sbi) * hblks_per_sec * hblks_per_sec, 100);
140         si->bimodal = div64_u64(bimodal, dist);
141         if (si->dirty_count)
142                 si->avg_vblocks = div_u64(total_vblocks, ndirty);
143         else
144                 si->avg_vblocks = 0;
145 }
146
147 /*
148  * This function calculates memory footprint.
149  */
150 static void update_mem_info(struct f2fs_sb_info *sbi)
151 {
152         struct f2fs_stat_info *si = F2FS_STAT(sbi);
153         unsigned npages;
154         int i;
155
156         if (si->base_mem)
157                 goto get_cache;
158
159         si->base_mem = sizeof(struct f2fs_sb_info) + sbi->sb->s_blocksize;
160         si->base_mem += 2 * sizeof(struct f2fs_inode_info);
161         si->base_mem += sizeof(*sbi->ckpt);
162         si->base_mem += sizeof(struct percpu_counter) * NR_COUNT_TYPE;
163
164         /* build sm */
165         si->base_mem += sizeof(struct f2fs_sm_info);
166
167         /* build sit */
168         si->base_mem += sizeof(struct sit_info);
169         si->base_mem += MAIN_SEGS(sbi) * sizeof(struct seg_entry);
170         si->base_mem += f2fs_bitmap_size(MAIN_SEGS(sbi));
171         si->base_mem += 2 * SIT_VBLOCK_MAP_SIZE * MAIN_SEGS(sbi);
172         if (f2fs_discard_en(sbi))
173                 si->base_mem += SIT_VBLOCK_MAP_SIZE * MAIN_SEGS(sbi);
174         si->base_mem += SIT_VBLOCK_MAP_SIZE;
175         if (sbi->segs_per_sec > 1)
176                 si->base_mem += MAIN_SECS(sbi) * sizeof(struct sec_entry);
177         si->base_mem += __bitmap_size(sbi, SIT_BITMAP);
178
179         /* build free segmap */
180         si->base_mem += sizeof(struct free_segmap_info);
181         si->base_mem += f2fs_bitmap_size(MAIN_SEGS(sbi));
182         si->base_mem += f2fs_bitmap_size(MAIN_SECS(sbi));
183
184         /* build curseg */
185         si->base_mem += sizeof(struct curseg_info) * NR_CURSEG_TYPE;
186         si->base_mem += PAGE_SIZE * NR_CURSEG_TYPE;
187
188         /* build dirty segmap */
189         si->base_mem += sizeof(struct dirty_seglist_info);
190         si->base_mem += NR_DIRTY_TYPE * f2fs_bitmap_size(MAIN_SEGS(sbi));
191         si->base_mem += f2fs_bitmap_size(MAIN_SECS(sbi));
192
193         /* build nm */
194         si->base_mem += sizeof(struct f2fs_nm_info);
195         si->base_mem += __bitmap_size(sbi, NAT_BITMAP);
196         si->base_mem += (NM_I(sbi)->nat_bits_blocks << F2FS_BLKSIZE_BITS);
197         si->base_mem += NM_I(sbi)->nat_blocks * NAT_ENTRY_BITMAP_SIZE;
198         si->base_mem += NM_I(sbi)->nat_blocks / 8;
199         si->base_mem += NM_I(sbi)->nat_blocks * sizeof(unsigned short);
200
201 get_cache:
202         si->cache_mem = 0;
203
204         /* build gc */
205         if (sbi->gc_thread)
206                 si->cache_mem += sizeof(struct f2fs_gc_kthread);
207
208         /* build merge flush thread */
209         if (SM_I(sbi)->fcc_info)
210                 si->cache_mem += sizeof(struct flush_cmd_control);
211         if (SM_I(sbi)->dcc_info)
212                 si->cache_mem += sizeof(struct discard_cmd_control);
213
214         /* free nids */
215         si->cache_mem += (NM_I(sbi)->nid_cnt[FREE_NID_LIST] +
216                                 NM_I(sbi)->nid_cnt[ALLOC_NID_LIST]) *
217                                 sizeof(struct free_nid);
218         si->cache_mem += NM_I(sbi)->nat_cnt * sizeof(struct nat_entry);
219         si->cache_mem += NM_I(sbi)->dirty_nat_cnt *
220                                         sizeof(struct nat_entry_set);
221         si->cache_mem += si->inmem_pages * sizeof(struct inmem_pages);
222         for (i = 0; i <= ORPHAN_INO; i++)
223                 si->cache_mem += sbi->im[i].ino_num * sizeof(struct ino_entry);
224         si->cache_mem += atomic_read(&sbi->total_ext_tree) *
225                                                 sizeof(struct extent_tree);
226         si->cache_mem += atomic_read(&sbi->total_ext_node) *
227                                                 sizeof(struct extent_node);
228
229         si->page_mem = 0;
230         npages = NODE_MAPPING(sbi)->nrpages;
231         si->page_mem += (unsigned long long)npages << PAGE_SHIFT;
232         npages = META_MAPPING(sbi)->nrpages;
233         si->page_mem += (unsigned long long)npages << PAGE_SHIFT;
234 }
235
236 static int stat_show(struct seq_file *s, void *v)
237 {
238         struct f2fs_stat_info *si;
239         int i = 0;
240         int j;
241
242         mutex_lock(&f2fs_stat_mutex);
243         list_for_each_entry(si, &f2fs_stat_list, stat_list) {
244                 update_general_status(si->sbi);
245
246                 seq_printf(s, "\n=====[ partition info(%pg). #%d, %s]=====\n",
247                         si->sbi->sb->s_bdev, i++,
248                         f2fs_readonly(si->sbi->sb) ? "RO": "RW");
249                 seq_printf(s, "[SB: 1] [CP: 2] [SIT: %d] [NAT: %d] ",
250                            si->sit_area_segs, si->nat_area_segs);
251                 seq_printf(s, "[SSA: %d] [MAIN: %d",
252                            si->ssa_area_segs, si->main_area_segs);
253                 seq_printf(s, "(OverProv:%d Resv:%d)]\n\n",
254                            si->overp_segs, si->rsvd_segs);
255                 if (test_opt(si->sbi, DISCARD))
256                         seq_printf(s, "Utilization: %u%% (%u valid blocks, %u discard blocks)\n",
257                                 si->utilization, si->valid_count, si->discard_blks);
258                 else
259                         seq_printf(s, "Utilization: %u%% (%u valid blocks)\n",
260                                 si->utilization, si->valid_count);
261
262                 seq_printf(s, "  - Node: %u (Inode: %u, ",
263                            si->valid_node_count, si->valid_inode_count);
264                 seq_printf(s, "Other: %u)\n  - Data: %u\n",
265                            si->valid_node_count - si->valid_inode_count,
266                            si->valid_count - si->valid_node_count);
267                 seq_printf(s, "  - Inline_xattr Inode: %u\n",
268                            si->inline_xattr);
269                 seq_printf(s, "  - Inline_data Inode: %u\n",
270                            si->inline_inode);
271                 seq_printf(s, "  - Inline_dentry Inode: %u\n",
272                            si->inline_dir);
273                 seq_printf(s, "  - Orphan/Append/Update Inode: %u, %u, %u\n",
274                            si->orphans, si->append, si->update);
275                 seq_printf(s, "\nMain area: %d segs, %d secs %d zones\n",
276                            si->main_area_segs, si->main_area_sections,
277                            si->main_area_zones);
278                 seq_printf(s, "  - COLD  data: %d, %d, %d\n",
279                            si->curseg[CURSEG_COLD_DATA],
280                            si->cursec[CURSEG_COLD_DATA],
281                            si->curzone[CURSEG_COLD_DATA]);
282                 seq_printf(s, "  - WARM  data: %d, %d, %d\n",
283                            si->curseg[CURSEG_WARM_DATA],
284                            si->cursec[CURSEG_WARM_DATA],
285                            si->curzone[CURSEG_WARM_DATA]);
286                 seq_printf(s, "  - HOT   data: %d, %d, %d\n",
287                            si->curseg[CURSEG_HOT_DATA],
288                            si->cursec[CURSEG_HOT_DATA],
289                            si->curzone[CURSEG_HOT_DATA]);
290                 seq_printf(s, "  - Dir   dnode: %d, %d, %d\n",
291                            si->curseg[CURSEG_HOT_NODE],
292                            si->cursec[CURSEG_HOT_NODE],
293                            si->curzone[CURSEG_HOT_NODE]);
294                 seq_printf(s, "  - File   dnode: %d, %d, %d\n",
295                            si->curseg[CURSEG_WARM_NODE],
296                            si->cursec[CURSEG_WARM_NODE],
297                            si->curzone[CURSEG_WARM_NODE]);
298                 seq_printf(s, "  - Indir nodes: %d, %d, %d\n",
299                            si->curseg[CURSEG_COLD_NODE],
300                            si->cursec[CURSEG_COLD_NODE],
301                            si->curzone[CURSEG_COLD_NODE]);
302                 seq_printf(s, "\n  - Valid: %d\n  - Dirty: %d\n",
303                            si->main_area_segs - si->dirty_count -
304                            si->prefree_count - si->free_segs,
305                            si->dirty_count);
306                 seq_printf(s, "  - Prefree: %d\n  - Free: %d (%d)\n\n",
307                            si->prefree_count, si->free_segs, si->free_secs);
308                 seq_printf(s, "CP calls: %d (BG: %d)\n",
309                                 si->cp_count, si->bg_cp_count);
310                 seq_printf(s, "GC calls: %d (BG: %d)\n",
311                            si->call_count, si->bg_gc);
312                 seq_printf(s, "  - data segments : %d (%d)\n",
313                                 si->data_segs, si->bg_data_segs);
314                 seq_printf(s, "  - node segments : %d (%d)\n",
315                                 si->node_segs, si->bg_node_segs);
316                 seq_printf(s, "Try to move %d blocks (BG: %d)\n", si->tot_blks,
317                                 si->bg_data_blks + si->bg_node_blks);
318                 seq_printf(s, "  - data blocks : %d (%d)\n", si->data_blks,
319                                 si->bg_data_blks);
320                 seq_printf(s, "  - node blocks : %d (%d)\n", si->node_blks,
321                                 si->bg_node_blks);
322                 seq_puts(s, "\nExtent Cache:\n");
323                 seq_printf(s, "  - Hit Count: L1-1:%llu L1-2:%llu L2:%llu\n",
324                                 si->hit_largest, si->hit_cached,
325                                 si->hit_rbtree);
326                 seq_printf(s, "  - Hit Ratio: %llu%% (%llu / %llu)\n",
327                                 !si->total_ext ? 0 :
328                                 div64_u64(si->hit_total * 100, si->total_ext),
329                                 si->hit_total, si->total_ext);
330                 seq_printf(s, "  - Inner Struct Count: tree: %d(%d), node: %d\n",
331                                 si->ext_tree, si->zombie_tree, si->ext_node);
332                 seq_puts(s, "\nBalancing F2FS Async:\n");
333                 seq_printf(s, "  - IO (CP: %4d, Data: %4d, Flush: %4d, Discard: %4d)\n",
334                            si->nr_wb_cp_data, si->nr_wb_data,
335                            si->nr_flush, si->nr_discard);
336                 seq_printf(s, "  - inmem: %4d, atomic IO: %4d (Max. %4d)\n",
337                            si->inmem_pages, si->aw_cnt, si->max_aw_cnt);
338                 seq_printf(s, "  - nodes: %4d in %4d\n",
339                            si->ndirty_node, si->node_pages);
340                 seq_printf(s, "  - dents: %4d in dirs:%4d (%4d)\n",
341                            si->ndirty_dent, si->ndirty_dirs, si->ndirty_all);
342                 seq_printf(s, "  - datas: %4d in files:%4d\n",
343                            si->ndirty_data, si->ndirty_files);
344                 seq_printf(s, "  - meta: %4d in %4d\n",
345                            si->ndirty_meta, si->meta_pages);
346                 seq_printf(s, "  - imeta: %4d\n",
347                            si->ndirty_imeta);
348                 seq_printf(s, "  - NATs: %9d/%9d\n  - SITs: %9d/%9d\n",
349                            si->dirty_nats, si->nats, si->dirty_sits, si->sits);
350                 seq_printf(s, "  - free_nids: %9d, alloc_nids: %9d\n",
351                            si->free_nids, si->alloc_nids);
352                 seq_puts(s, "\nDistribution of User Blocks:");
353                 seq_puts(s, " [ valid | invalid | free ]\n");
354                 seq_puts(s, "  [");
355
356                 for (j = 0; j < si->util_valid; j++)
357                         seq_putc(s, '-');
358                 seq_putc(s, '|');
359
360                 for (j = 0; j < si->util_invalid; j++)
361                         seq_putc(s, '-');
362                 seq_putc(s, '|');
363
364                 for (j = 0; j < si->util_free; j++)
365                         seq_putc(s, '-');
366                 seq_puts(s, "]\n\n");
367                 seq_printf(s, "IPU: %u blocks\n", si->inplace_count);
368                 seq_printf(s, "SSR: %u blocks in %u segments\n",
369                            si->block_count[SSR], si->segment_count[SSR]);
370                 seq_printf(s, "LFS: %u blocks in %u segments\n",
371                            si->block_count[LFS], si->segment_count[LFS]);
372
373                 /* segment usage info */
374                 update_sit_info(si->sbi);
375                 seq_printf(s, "\nBDF: %u, avg. vblocks: %u\n",
376                            si->bimodal, si->avg_vblocks);
377
378                 /* memory footprint */
379                 update_mem_info(si->sbi);
380                 seq_printf(s, "\nMemory: %llu KB\n",
381                         (si->base_mem + si->cache_mem + si->page_mem) >> 10);
382                 seq_printf(s, "  - static: %llu KB\n",
383                                 si->base_mem >> 10);
384                 seq_printf(s, "  - cached: %llu KB\n",
385                                 si->cache_mem >> 10);
386                 seq_printf(s, "  - paged : %llu KB\n",
387                                 si->page_mem >> 10);
388         }
389         mutex_unlock(&f2fs_stat_mutex);
390         return 0;
391 }
392
393 static int stat_open(struct inode *inode, struct file *file)
394 {
395         return single_open(file, stat_show, inode->i_private);
396 }
397
398 static const struct file_operations stat_fops = {
399         .owner = THIS_MODULE,
400         .open = stat_open,
401         .read = seq_read,
402         .llseek = seq_lseek,
403         .release = single_release,
404 };
405
406 int f2fs_build_stats(struct f2fs_sb_info *sbi)
407 {
408         struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
409         struct f2fs_stat_info *si;
410
411         si = kzalloc(sizeof(struct f2fs_stat_info), GFP_KERNEL);
412         if (!si)
413                 return -ENOMEM;
414
415         si->all_area_segs = le32_to_cpu(raw_super->segment_count);
416         si->sit_area_segs = le32_to_cpu(raw_super->segment_count_sit);
417         si->nat_area_segs = le32_to_cpu(raw_super->segment_count_nat);
418         si->ssa_area_segs = le32_to_cpu(raw_super->segment_count_ssa);
419         si->main_area_segs = le32_to_cpu(raw_super->segment_count_main);
420         si->main_area_sections = le32_to_cpu(raw_super->section_count);
421         si->main_area_zones = si->main_area_sections /
422                                 le32_to_cpu(raw_super->secs_per_zone);
423         si->sbi = sbi;
424         sbi->stat_info = si;
425
426         atomic64_set(&sbi->total_hit_ext, 0);
427         atomic64_set(&sbi->read_hit_rbtree, 0);
428         atomic64_set(&sbi->read_hit_largest, 0);
429         atomic64_set(&sbi->read_hit_cached, 0);
430
431         atomic_set(&sbi->inline_xattr, 0);
432         atomic_set(&sbi->inline_inode, 0);
433         atomic_set(&sbi->inline_dir, 0);
434         atomic_set(&sbi->inplace_count, 0);
435
436         atomic_set(&sbi->aw_cnt, 0);
437         atomic_set(&sbi->max_aw_cnt, 0);
438
439         mutex_lock(&f2fs_stat_mutex);
440         list_add_tail(&si->stat_list, &f2fs_stat_list);
441         mutex_unlock(&f2fs_stat_mutex);
442
443         return 0;
444 }
445
446 void f2fs_destroy_stats(struct f2fs_sb_info *sbi)
447 {
448         struct f2fs_stat_info *si = F2FS_STAT(sbi);
449
450         mutex_lock(&f2fs_stat_mutex);
451         list_del(&si->stat_list);
452         mutex_unlock(&f2fs_stat_mutex);
453
454         kfree(si);
455 }
456
457 int __init f2fs_create_root_stats(void)
458 {
459         struct dentry *file;
460
461         f2fs_debugfs_root = debugfs_create_dir("f2fs", NULL);
462         if (!f2fs_debugfs_root)
463                 return -ENOMEM;
464
465         file = debugfs_create_file("status", S_IRUGO, f2fs_debugfs_root,
466                         NULL, &stat_fops);
467         if (!file) {
468                 debugfs_remove(f2fs_debugfs_root);
469                 f2fs_debugfs_root = NULL;
470                 return -ENOMEM;
471         }
472
473         return 0;
474 }
475
476 void f2fs_destroy_root_stats(void)
477 {
478         if (!f2fs_debugfs_root)
479                 return;
480
481         debugfs_remove_recursive(f2fs_debugfs_root);
482         f2fs_debugfs_root = NULL;
483 }