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alistair23-linux/fs/f2fs/debug.c
Chao Yu 2ef79ecb5e f2fs: avoid stucking GC due to atomic write 
f2fs doesn't allow abuse on atomic write class interface, so except
limiting in-mem pages' total memory usage capacity, we need to limit
atomic-write usage as well when filesystem is seriously fragmented,
otherwise we may run into infinite loop during foreground GC because
target blocks in victim segment are belong to atomic opened file for
long time.

Now, we will detect failure due to atomic write in foreground GC, if
the count exceeds threshold, we will drop all atomic written data in
cache, by this, I expect it can keep our system running safely to
prevent Dos attack.

In addition, his patch adds to show GC skip information in debugfs,
now it just shows count of skipped caused by atomic write.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-05-31 11:31:51 -07:00

523 lines
18 KiB
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Raw Blame History

/*
* f2fs debugging statistics
*
* Copyright (c) 2012 Samsung Electronics Co., Ltd.
* http://www.samsung.com/
* Copyright (c) 2012 Linux Foundation
* Copyright (c) 2012 Greg Kroah-Hartman <gregkh@linuxfoundation.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/fs.h>
#include <linux/backing-dev.h>
#include <linux/f2fs_fs.h>
#include <linux/blkdev.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include "f2fs.h"
#include "node.h"
#include "segment.h"
#include "gc.h"
static LIST_HEAD(f2fs_stat_list);
static struct dentry *f2fs_debugfs_root;
static DEFINE_MUTEX(f2fs_stat_mutex);
static void update_general_status(struct f2fs_sb_info *sbi)
{
struct f2fs_stat_info *si = F2FS_STAT(sbi);
int i;
/* validation check of the segment numbers */
si->hit_largest = atomic64_read(&sbi->read_hit_largest);
si->hit_cached = atomic64_read(&sbi->read_hit_cached);
si->hit_rbtree = atomic64_read(&sbi->read_hit_rbtree);
si->hit_total = si->hit_largest + si->hit_cached + si->hit_rbtree;
si->total_ext = atomic64_read(&sbi->total_hit_ext);
si->ext_tree = atomic_read(&sbi->total_ext_tree);
si->zombie_tree = atomic_read(&sbi->total_zombie_tree);
si->ext_node = atomic_read(&sbi->total_ext_node);
si->ndirty_node = get_pages(sbi, F2FS_DIRTY_NODES);
si->ndirty_dent = get_pages(sbi, F2FS_DIRTY_DENTS);
si->ndirty_meta = get_pages(sbi, F2FS_DIRTY_META);
si->ndirty_data = get_pages(sbi, F2FS_DIRTY_DATA);
si->ndirty_qdata = get_pages(sbi, F2FS_DIRTY_QDATA);
si->ndirty_imeta = get_pages(sbi, F2FS_DIRTY_IMETA);
si->ndirty_dirs = sbi->ndirty_inode[DIR_INODE];
si->ndirty_files = sbi->ndirty_inode[FILE_INODE];
si->nquota_files = sbi->nquota_files;
si->ndirty_all = sbi->ndirty_inode[DIRTY_META];
si->inmem_pages = get_pages(sbi, F2FS_INMEM_PAGES);
si->aw_cnt = atomic_read(&sbi->aw_cnt);
si->vw_cnt = atomic_read(&sbi->vw_cnt);
si->max_aw_cnt = atomic_read(&sbi->max_aw_cnt);
si->max_vw_cnt = atomic_read(&sbi->max_vw_cnt);
si->nr_wb_cp_data = get_pages(sbi, F2FS_WB_CP_DATA);
si->nr_wb_data = get_pages(sbi, F2FS_WB_DATA);
if (SM_I(sbi) && SM_I(sbi)->fcc_info) {
si->nr_flushed =
atomic_read(&SM_I(sbi)->fcc_info->issued_flush);
si->nr_flushing =
atomic_read(&SM_I(sbi)->fcc_info->issing_flush);
si->flush_list_empty =
llist_empty(&SM_I(sbi)->fcc_info->issue_list);
}
if (SM_I(sbi) && SM_I(sbi)->dcc_info) {
si->nr_discarded =
atomic_read(&SM_I(sbi)->dcc_info->issued_discard);
si->nr_discarding =
atomic_read(&SM_I(sbi)->dcc_info->issing_discard);
si->nr_discard_cmd =
atomic_read(&SM_I(sbi)->dcc_info->discard_cmd_cnt);
si->undiscard_blks = SM_I(sbi)->dcc_info->undiscard_blks;
}
si->total_count = (int)sbi->user_block_count / sbi->blocks_per_seg;
si->rsvd_segs = reserved_segments(sbi);
si->overp_segs = overprovision_segments(sbi);
si->valid_count = valid_user_blocks(sbi);
si->discard_blks = discard_blocks(sbi);
si->valid_node_count = valid_node_count(sbi);
si->valid_inode_count = valid_inode_count(sbi);
si->inline_xattr = atomic_read(&sbi->inline_xattr);
si->inline_inode = atomic_read(&sbi->inline_inode);
si->inline_dir = atomic_read(&sbi->inline_dir);
si->append = sbi->im[APPEND_INO].ino_num;
si->update = sbi->im[UPDATE_INO].ino_num;
si->orphans = sbi->im[ORPHAN_INO].ino_num;
si->utilization = utilization(sbi);
si->free_segs = free_segments(sbi);
si->free_secs = free_sections(sbi);
si->prefree_count = prefree_segments(sbi);
si->dirty_count = dirty_segments(sbi);
si->node_pages = NODE_MAPPING(sbi)->nrpages;
si->meta_pages = META_MAPPING(sbi)->nrpages;
si->nats = NM_I(sbi)->nat_cnt;
si->dirty_nats = NM_I(sbi)->dirty_nat_cnt;
si->sits = MAIN_SEGS(sbi);
si->dirty_sits = SIT_I(sbi)->dirty_sentries;
si->free_nids = NM_I(sbi)->nid_cnt[FREE_NID];
si->avail_nids = NM_I(sbi)->available_nids;
si->alloc_nids = NM_I(sbi)->nid_cnt[PREALLOC_NID];
si->bg_gc = sbi->bg_gc;
si->skipped_atomic_files[BG_GC] = sbi->skipped_atomic_files[BG_GC];
si->skipped_atomic_files[FG_GC] = sbi->skipped_atomic_files[FG_GC];
si->util_free = (int)(free_user_blocks(sbi) >> sbi->log_blocks_per_seg)
* 100 / (int)(sbi->user_block_count >> sbi->log_blocks_per_seg)
/ 2;
si->util_valid = (int)(written_block_count(sbi) >>
sbi->log_blocks_per_seg)
* 100 / (int)(sbi->user_block_count >> sbi->log_blocks_per_seg)
/ 2;
si->util_invalid = 50 - si->util_free - si->util_valid;
for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_NODE; i++) {
struct curseg_info *curseg = CURSEG_I(sbi, i);
si->curseg[i] = curseg->segno;
si->cursec[i] = GET_SEC_FROM_SEG(sbi, curseg->segno);
si->curzone[i] = GET_ZONE_FROM_SEC(sbi, si->cursec[i]);
}
for (i = 0; i < 2; i++) {
si->segment_count[i] = sbi->segment_count[i];
si->block_count[i] = sbi->block_count[i];
}
si->inplace_count = atomic_read(&sbi->inplace_count);
}
/*
* This function calculates BDF of every segments
*/
static void update_sit_info(struct f2fs_sb_info *sbi)
{
struct f2fs_stat_info *si = F2FS_STAT(sbi);
unsigned long long blks_per_sec, hblks_per_sec, total_vblocks;
unsigned long long bimodal, dist;
unsigned int segno, vblocks;
int ndirty = 0;
bimodal = 0;
total_vblocks = 0;
blks_per_sec = BLKS_PER_SEC(sbi);
hblks_per_sec = blks_per_sec / 2;
for (segno = 0; segno < MAIN_SEGS(sbi); segno += sbi->segs_per_sec) {
vblocks = get_valid_blocks(sbi, segno, true);
dist = abs(vblocks - hblks_per_sec);
bimodal += dist * dist;
if (vblocks > 0 && vblocks < blks_per_sec) {
total_vblocks += vblocks;
ndirty++;
}
}
dist = div_u64(MAIN_SECS(sbi) * hblks_per_sec * hblks_per_sec, 100);
si->bimodal = div64_u64(bimodal, dist);
if (si->dirty_count)
si->avg_vblocks = div_u64(total_vblocks, ndirty);
else
si->avg_vblocks = 0;
}
/*
* This function calculates memory footprint.
*/
static void update_mem_info(struct f2fs_sb_info *sbi)
{
struct f2fs_stat_info *si = F2FS_STAT(sbi);
unsigned npages;
int i;
if (si->base_mem)
goto get_cache;
/* build stat */
si->base_mem = sizeof(struct f2fs_stat_info);
/* build superblock */
si->base_mem += sizeof(struct f2fs_sb_info) + sbi->sb->s_blocksize;
si->base_mem += 2 * sizeof(struct f2fs_inode_info);
si->base_mem += sizeof(*sbi->ckpt);
/* build sm */
si->base_mem += sizeof(struct f2fs_sm_info);
/* build sit */
si->base_mem += sizeof(struct sit_info);
si->base_mem += MAIN_SEGS(sbi) * sizeof(struct seg_entry);
si->base_mem += f2fs_bitmap_size(MAIN_SEGS(sbi));
si->base_mem += 2 * SIT_VBLOCK_MAP_SIZE * MAIN_SEGS(sbi);
if (f2fs_discard_en(sbi))
si->base_mem += SIT_VBLOCK_MAP_SIZE * MAIN_SEGS(sbi);
si->base_mem += SIT_VBLOCK_MAP_SIZE;
if (sbi->segs_per_sec > 1)
si->base_mem += MAIN_SECS(sbi) * sizeof(struct sec_entry);
si->base_mem += __bitmap_size(sbi, SIT_BITMAP);
/* build free segmap */
si->base_mem += sizeof(struct free_segmap_info);
si->base_mem += f2fs_bitmap_size(MAIN_SEGS(sbi));
si->base_mem += f2fs_bitmap_size(MAIN_SECS(sbi));
/* build curseg */
si->base_mem += sizeof(struct curseg_info) * NR_CURSEG_TYPE;
si->base_mem += PAGE_SIZE * NR_CURSEG_TYPE;
/* build dirty segmap */
si->base_mem += sizeof(struct dirty_seglist_info);
si->base_mem += NR_DIRTY_TYPE * f2fs_bitmap_size(MAIN_SEGS(sbi));
si->base_mem += f2fs_bitmap_size(MAIN_SECS(sbi));
/* build nm */
si->base_mem += sizeof(struct f2fs_nm_info);
si->base_mem += __bitmap_size(sbi, NAT_BITMAP);
si->base_mem += (NM_I(sbi)->nat_bits_blocks << F2FS_BLKSIZE_BITS);
si->base_mem += NM_I(sbi)->nat_blocks * NAT_ENTRY_BITMAP_SIZE;
si->base_mem += NM_I(sbi)->nat_blocks / 8;
si->base_mem += NM_I(sbi)->nat_blocks * sizeof(unsigned short);
get_cache:
si->cache_mem = 0;
/* build gc */
if (sbi->gc_thread)
si->cache_mem += sizeof(struct f2fs_gc_kthread);
/* build merge flush thread */
if (SM_I(sbi)->fcc_info)
si->cache_mem += sizeof(struct flush_cmd_control);
if (SM_I(sbi)->dcc_info) {
si->cache_mem += sizeof(struct discard_cmd_control);
si->cache_mem += sizeof(struct discard_cmd) *
atomic_read(&SM_I(sbi)->dcc_info->discard_cmd_cnt);
}
/* free nids */
si->cache_mem += (NM_I(sbi)->nid_cnt[FREE_NID] +
NM_I(sbi)->nid_cnt[PREALLOC_NID]) *
sizeof(struct free_nid);
si->cache_mem += NM_I(sbi)->nat_cnt * sizeof(struct nat_entry);
si->cache_mem += NM_I(sbi)->dirty_nat_cnt *
sizeof(struct nat_entry_set);
si->cache_mem += si->inmem_pages * sizeof(struct inmem_pages);
for (i = 0; i < MAX_INO_ENTRY; i++)
si->cache_mem += sbi->im[i].ino_num * sizeof(struct ino_entry);
si->cache_mem += atomic_read(&sbi->total_ext_tree) *
sizeof(struct extent_tree);
si->cache_mem += atomic_read(&sbi->total_ext_node) *
sizeof(struct extent_node);
si->page_mem = 0;
npages = NODE_MAPPING(sbi)->nrpages;
si->page_mem += (unsigned long long)npages << PAGE_SHIFT;
npages = META_MAPPING(sbi)->nrpages;
si->page_mem += (unsigned long long)npages << PAGE_SHIFT;
}
static int stat_show(struct seq_file *s, void *v)
{
struct f2fs_stat_info *si;
int i = 0;
int j;
mutex_lock(&f2fs_stat_mutex);
list_for_each_entry(si, &f2fs_stat_list, stat_list) {
update_general_status(si->sbi);
seq_printf(s, "\n=====[ partition info(%pg). #%d, %s, CP: %s]=====\n",
si->sbi->sb->s_bdev, i++,
f2fs_readonly(si->sbi->sb) ? "RO": "RW",
f2fs_cp_error(si->sbi) ? "Error": "Good");
seq_printf(s, "[SB: 1] [CP: 2] [SIT: %d] [NAT: %d] ",
si->sit_area_segs, si->nat_area_segs);
seq_printf(s, "[SSA: %d] [MAIN: %d",
si->ssa_area_segs, si->main_area_segs);
seq_printf(s, "(OverProv:%d Resv:%d)]\n\n",
si->overp_segs, si->rsvd_segs);
if (test_opt(si->sbi, DISCARD))
seq_printf(s, "Utilization: %u%% (%u valid blocks, %u discard blocks)\n",
si->utilization, si->valid_count, si->discard_blks);
else
seq_printf(s, "Utilization: %u%% (%u valid blocks)\n",
si->utilization, si->valid_count);
seq_printf(s, " - Node: %u (Inode: %u, ",
si->valid_node_count, si->valid_inode_count);
seq_printf(s, "Other: %u)\n - Data: %u\n",
si->valid_node_count - si->valid_inode_count,
si->valid_count - si->valid_node_count);
seq_printf(s, " - Inline_xattr Inode: %u\n",
si->inline_xattr);
seq_printf(s, " - Inline_data Inode: %u\n",
si->inline_inode);
seq_printf(s, " - Inline_dentry Inode: %u\n",
si->inline_dir);
seq_printf(s, " - Orphan/Append/Update Inode: %u, %u, %u\n",
si->orphans, si->append, si->update);
seq_printf(s, "\nMain area: %d segs, %d secs %d zones\n",
si->main_area_segs, si->main_area_sections,
si->main_area_zones);
seq_printf(s, " - COLD data: %d, %d, %d\n",
si->curseg[CURSEG_COLD_DATA],
si->cursec[CURSEG_COLD_DATA],
si->curzone[CURSEG_COLD_DATA]);
seq_printf(s, " - WARM data: %d, %d, %d\n",
si->curseg[CURSEG_WARM_DATA],
si->cursec[CURSEG_WARM_DATA],
si->curzone[CURSEG_WARM_DATA]);
seq_printf(s, " - HOT data: %d, %d, %d\n",
si->curseg[CURSEG_HOT_DATA],
si->cursec[CURSEG_HOT_DATA],
si->curzone[CURSEG_HOT_DATA]);
seq_printf(s, " - Dir dnode: %d, %d, %d\n",
si->curseg[CURSEG_HOT_NODE],
si->cursec[CURSEG_HOT_NODE],
si->curzone[CURSEG_HOT_NODE]);
seq_printf(s, " - File dnode: %d, %d, %d\n",
si->curseg[CURSEG_WARM_NODE],
si->cursec[CURSEG_WARM_NODE],
si->curzone[CURSEG_WARM_NODE]);
seq_printf(s, " - Indir nodes: %d, %d, %d\n",
si->curseg[CURSEG_COLD_NODE],
si->cursec[CURSEG_COLD_NODE],
si->curzone[CURSEG_COLD_NODE]);
seq_printf(s, "\n - Valid: %d\n - Dirty: %d\n",
si->main_area_segs - si->dirty_count -
si->prefree_count - si->free_segs,
si->dirty_count);
seq_printf(s, " - Prefree: %d\n - Free: %d (%d)\n\n",
si->prefree_count, si->free_segs, si->free_secs);
seq_printf(s, "CP calls: %d (BG: %d)\n",
si->cp_count, si->bg_cp_count);
seq_printf(s, "GC calls: %d (BG: %d)\n",
si->call_count, si->bg_gc);
seq_printf(s, " - data segments : %d (%d)\n",
si->data_segs, si->bg_data_segs);
seq_printf(s, " - node segments : %d (%d)\n",
si->node_segs, si->bg_node_segs);
seq_printf(s, "Try to move %d blocks (BG: %d)\n", si->tot_blks,
si->bg_data_blks + si->bg_node_blks);
seq_printf(s, " - data blocks : %d (%d)\n", si->data_blks,
si->bg_data_blks);
seq_printf(s, " - node blocks : %d (%d)\n", si->node_blks,
si->bg_node_blks);
seq_printf(s, "Skipped : atomic write %llu (%llu)\n",
si->skipped_atomic_files[BG_GC] +
si->skipped_atomic_files[FG_GC],
si->skipped_atomic_files[BG_GC]);
seq_puts(s, "\nExtent Cache:\n");
seq_printf(s, " - Hit Count: L1-1:%llu L1-2:%llu L2:%llu\n",
si->hit_largest, si->hit_cached,
si->hit_rbtree);
seq_printf(s, " - Hit Ratio: %llu%% (%llu / %llu)\n",
!si->total_ext ? 0 :
div64_u64(si->hit_total * 100, si->total_ext),
si->hit_total, si->total_ext);
seq_printf(s, " - Inner Struct Count: tree: %d(%d), node: %d\n",
si->ext_tree, si->zombie_tree, si->ext_node);
seq_puts(s, "\nBalancing F2FS Async:\n");
seq_printf(s, " - IO (CP: %4d, Data: %4d, Flush: (%4d %4d %4d), "
"Discard: (%4d %4d)) cmd: %4d undiscard:%4u\n",
si->nr_wb_cp_data, si->nr_wb_data,
si->nr_flushing, si->nr_flushed,
si->flush_list_empty,
si->nr_discarding, si->nr_discarded,
si->nr_discard_cmd, si->undiscard_blks);
seq_printf(s, " - inmem: %4d, atomic IO: %4d (Max. %4d), "
"volatile IO: %4d (Max. %4d)\n",
si->inmem_pages, si->aw_cnt, si->max_aw_cnt,
si->vw_cnt, si->max_vw_cnt);
seq_printf(s, " - nodes: %4d in %4d\n",
si->ndirty_node, si->node_pages);
seq_printf(s, " - dents: %4d in dirs:%4d (%4d)\n",
si->ndirty_dent, si->ndirty_dirs, si->ndirty_all);
seq_printf(s, " - datas: %4d in files:%4d\n",
si->ndirty_data, si->ndirty_files);
seq_printf(s, " - quota datas: %4d in quota files:%4d\n",
si->ndirty_qdata, si->nquota_files);
seq_printf(s, " - meta: %4d in %4d\n",
si->ndirty_meta, si->meta_pages);
seq_printf(s, " - imeta: %4d\n",
si->ndirty_imeta);
seq_printf(s, " - NATs: %9d/%9d\n - SITs: %9d/%9d\n",
si->dirty_nats, si->nats, si->dirty_sits, si->sits);
seq_printf(s, " - free_nids: %9d/%9d\n - alloc_nids: %9d\n",
si->free_nids, si->avail_nids, si->alloc_nids);
seq_puts(s, "\nDistribution of User Blocks:");
seq_puts(s, " [ valid | invalid | free ]\n");
seq_puts(s, " [");
for (j = 0; j < si->util_valid; j++)
seq_putc(s, '-');
seq_putc(s, '|');
for (j = 0; j < si->util_invalid; j++)
seq_putc(s, '-');
seq_putc(s, '|');
for (j = 0; j < si->util_free; j++)
seq_putc(s, '-');
seq_puts(s, "]\n\n");
seq_printf(s, "IPU: %u blocks\n", si->inplace_count);
seq_printf(s, "SSR: %u blocks in %u segments\n",
si->block_count[SSR], si->segment_count[SSR]);
seq_printf(s, "LFS: %u blocks in %u segments\n",
si->block_count[LFS], si->segment_count[LFS]);
/* segment usage info */
update_sit_info(si->sbi);
seq_printf(s, "\nBDF: %u, avg. vblocks: %u\n",
si->bimodal, si->avg_vblocks);
/* memory footprint */
update_mem_info(si->sbi);
seq_printf(s, "\nMemory: %llu KB\n",
(si->base_mem + si->cache_mem + si->page_mem) >> 10);
seq_printf(s, " - static: %llu KB\n",
si->base_mem >> 10);
seq_printf(s, " - cached: %llu KB\n",
si->cache_mem >> 10);
seq_printf(s, " - paged : %llu KB\n",
si->page_mem >> 10);
}
mutex_unlock(&f2fs_stat_mutex);
return 0;
}
static int stat_open(struct inode *inode, struct file *file)
{
return single_open(file, stat_show, inode->i_private);
}
static const struct file_operations stat_fops = {
.owner = THIS_MODULE,
.open = stat_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
int f2fs_build_stats(struct f2fs_sb_info *sbi)
{
struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
struct f2fs_stat_info *si;
si = f2fs_kzalloc(sbi, sizeof(struct f2fs_stat_info), GFP_KERNEL);
if (!si)
return -ENOMEM;
si->all_area_segs = le32_to_cpu(raw_super->segment_count);
si->sit_area_segs = le32_to_cpu(raw_super->segment_count_sit);
si->nat_area_segs = le32_to_cpu(raw_super->segment_count_nat);
si->ssa_area_segs = le32_to_cpu(raw_super->segment_count_ssa);
si->main_area_segs = le32_to_cpu(raw_super->segment_count_main);
si->main_area_sections = le32_to_cpu(raw_super->section_count);
si->main_area_zones = si->main_area_sections /
le32_to_cpu(raw_super->secs_per_zone);
si->sbi = sbi;
sbi->stat_info = si;
atomic64_set(&sbi->total_hit_ext, 0);
atomic64_set(&sbi->read_hit_rbtree, 0);
atomic64_set(&sbi->read_hit_largest, 0);
atomic64_set(&sbi->read_hit_cached, 0);
atomic_set(&sbi->inline_xattr, 0);
atomic_set(&sbi->inline_inode, 0);
atomic_set(&sbi->inline_dir, 0);
atomic_set(&sbi->inplace_count, 0);
atomic_set(&sbi->aw_cnt, 0);
atomic_set(&sbi->vw_cnt, 0);
atomic_set(&sbi->max_aw_cnt, 0);
atomic_set(&sbi->max_vw_cnt, 0);
mutex_lock(&f2fs_stat_mutex);
list_add_tail(&si->stat_list, &f2fs_stat_list);
mutex_unlock(&f2fs_stat_mutex);
return 0;
}
void f2fs_destroy_stats(struct f2fs_sb_info *sbi)
{
struct f2fs_stat_info *si = F2FS_STAT(sbi);
mutex_lock(&f2fs_stat_mutex);
list_del(&si->stat_list);
mutex_unlock(&f2fs_stat_mutex);
kfree(si);
}
int __init f2fs_create_root_stats(void)
{
struct dentry *file;
f2fs_debugfs_root = debugfs_create_dir("f2fs", NULL);
if (!f2fs_debugfs_root)
return -ENOMEM;
file = debugfs_create_file("status", S_IRUGO, f2fs_debugfs_root,
NULL, &stat_fops);
if (!file) {
debugfs_remove(f2fs_debugfs_root);
f2fs_debugfs_root = NULL;
return -ENOMEM;
}
return 0;
}
void f2fs_destroy_root_stats(void)
{
if (!f2fs_debugfs_root)
return;
debugfs_remove_recursive(f2fs_debugfs_root);
f2fs_debugfs_root = NULL;
}
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