xref: /linux/fs/f2fs/debug.c (revision 975ef7ff81bb000af6e6c8e63e81f89f3468dcf7)
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_qdata = get_pages(sbi, F2FS_DIRTY_QDATA);
49 	si->ndirty_imeta = get_pages(sbi, F2FS_DIRTY_IMETA);
50 	si->ndirty_dirs = sbi->ndirty_inode[DIR_INODE];
51 	si->ndirty_files = sbi->ndirty_inode[FILE_INODE];
52 	si->nquota_files = sbi->nquota_files;
53 	si->ndirty_all = sbi->ndirty_inode[DIRTY_META];
54 	si->inmem_pages = get_pages(sbi, F2FS_INMEM_PAGES);
55 	si->aw_cnt = atomic_read(&sbi->aw_cnt);
56 	si->vw_cnt = atomic_read(&sbi->vw_cnt);
57 	si->max_aw_cnt = atomic_read(&sbi->max_aw_cnt);
58 	si->max_vw_cnt = atomic_read(&sbi->max_vw_cnt);
59 	si->nr_wb_cp_data = get_pages(sbi, F2FS_WB_CP_DATA);
60 	si->nr_wb_data = get_pages(sbi, F2FS_WB_DATA);
61 	if (SM_I(sbi) && SM_I(sbi)->fcc_info) {
62 		si->nr_flushed =
63 			atomic_read(&SM_I(sbi)->fcc_info->issued_flush);
64 		si->nr_flushing =
65 			atomic_read(&SM_I(sbi)->fcc_info->issing_flush);
66 		si->flush_list_empty =
67 			llist_empty(&SM_I(sbi)->fcc_info->issue_list);
68 	}
69 	if (SM_I(sbi) && SM_I(sbi)->dcc_info) {
70 		si->nr_discarded =
71 			atomic_read(&SM_I(sbi)->dcc_info->issued_discard);
72 		si->nr_discarding =
73 			atomic_read(&SM_I(sbi)->dcc_info->issing_discard);
74 		si->nr_discard_cmd =
75 			atomic_read(&SM_I(sbi)->dcc_info->discard_cmd_cnt);
76 		si->undiscard_blks = SM_I(sbi)->dcc_info->undiscard_blks;
77 	}
78 	si->total_count = (int)sbi->user_block_count / sbi->blocks_per_seg;
79 	si->rsvd_segs = reserved_segments(sbi);
80 	si->overp_segs = overprovision_segments(sbi);
81 	si->valid_count = valid_user_blocks(sbi);
82 	si->discard_blks = discard_blocks(sbi);
83 	si->valid_node_count = valid_node_count(sbi);
84 	si->valid_inode_count = valid_inode_count(sbi);
85 	si->inline_xattr = atomic_read(&sbi->inline_xattr);
86 	si->inline_inode = atomic_read(&sbi->inline_inode);
87 	si->inline_dir = atomic_read(&sbi->inline_dir);
88 	si->append = sbi->im[APPEND_INO].ino_num;
89 	si->update = sbi->im[UPDATE_INO].ino_num;
90 	si->orphans = sbi->im[ORPHAN_INO].ino_num;
91 	si->utilization = utilization(sbi);
92 
93 	si->free_segs = free_segments(sbi);
94 	si->free_secs = free_sections(sbi);
95 	si->prefree_count = prefree_segments(sbi);
96 	si->dirty_count = dirty_segments(sbi);
97 	si->node_pages = NODE_MAPPING(sbi)->nrpages;
98 	si->meta_pages = META_MAPPING(sbi)->nrpages;
99 	si->nats = NM_I(sbi)->nat_cnt;
100 	si->dirty_nats = NM_I(sbi)->dirty_nat_cnt;
101 	si->sits = MAIN_SEGS(sbi);
102 	si->dirty_sits = SIT_I(sbi)->dirty_sentries;
103 	si->free_nids = NM_I(sbi)->nid_cnt[FREE_NID];
104 	si->avail_nids = NM_I(sbi)->available_nids;
105 	si->alloc_nids = NM_I(sbi)->nid_cnt[PREALLOC_NID];
106 	si->bg_gc = sbi->bg_gc;
107 	si->skipped_atomic_files[BG_GC] = sbi->skipped_atomic_files[BG_GC];
108 	si->skipped_atomic_files[FG_GC] = sbi->skipped_atomic_files[FG_GC];
109 	si->util_free = (int)(free_user_blocks(sbi) >> sbi->log_blocks_per_seg)
110 		* 100 / (int)(sbi->user_block_count >> sbi->log_blocks_per_seg)
111 		/ 2;
112 	si->util_valid = (int)(written_block_count(sbi) >>
113 						sbi->log_blocks_per_seg)
114 		* 100 / (int)(sbi->user_block_count >> sbi->log_blocks_per_seg)
115 		/ 2;
116 	si->util_invalid = 50 - si->util_free - si->util_valid;
117 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_NODE; i++) {
118 		struct curseg_info *curseg = CURSEG_I(sbi, i);
119 		si->curseg[i] = curseg->segno;
120 		si->cursec[i] = GET_SEC_FROM_SEG(sbi, curseg->segno);
121 		si->curzone[i] = GET_ZONE_FROM_SEC(sbi, si->cursec[i]);
122 	}
123 
124 	for (i = 0; i < 2; i++) {
125 		si->segment_count[i] = sbi->segment_count[i];
126 		si->block_count[i] = sbi->block_count[i];
127 	}
128 
129 	si->inplace_count = atomic_read(&sbi->inplace_count);
130 }
131 
132 /*
133  * This function calculates BDF of every segments
134  */
135 static void update_sit_info(struct f2fs_sb_info *sbi)
136 {
137 	struct f2fs_stat_info *si = F2FS_STAT(sbi);
138 	unsigned long long blks_per_sec, hblks_per_sec, total_vblocks;
139 	unsigned long long bimodal, dist;
140 	unsigned int segno, vblocks;
141 	int ndirty = 0;
142 
143 	bimodal = 0;
144 	total_vblocks = 0;
145 	blks_per_sec = BLKS_PER_SEC(sbi);
146 	hblks_per_sec = blks_per_sec / 2;
147 	for (segno = 0; segno < MAIN_SEGS(sbi); segno += sbi->segs_per_sec) {
148 		vblocks = get_valid_blocks(sbi, segno, true);
149 		dist = abs(vblocks - hblks_per_sec);
150 		bimodal += dist * dist;
151 
152 		if (vblocks > 0 && vblocks < blks_per_sec) {
153 			total_vblocks += vblocks;
154 			ndirty++;
155 		}
156 	}
157 	dist = div_u64(MAIN_SECS(sbi) * hblks_per_sec * hblks_per_sec, 100);
158 	si->bimodal = div64_u64(bimodal, dist);
159 	if (si->dirty_count)
160 		si->avg_vblocks = div_u64(total_vblocks, ndirty);
161 	else
162 		si->avg_vblocks = 0;
163 }
164 
165 /*
166  * This function calculates memory footprint.
167  */
168 static void update_mem_info(struct f2fs_sb_info *sbi)
169 {
170 	struct f2fs_stat_info *si = F2FS_STAT(sbi);
171 	unsigned npages;
172 	int i;
173 
174 	if (si->base_mem)
175 		goto get_cache;
176 
177 	/* build stat */
178 	si->base_mem = sizeof(struct f2fs_stat_info);
179 
180 	/* build superblock */
181 	si->base_mem += sizeof(struct f2fs_sb_info) + sbi->sb->s_blocksize;
182 	si->base_mem += 2 * sizeof(struct f2fs_inode_info);
183 	si->base_mem += sizeof(*sbi->ckpt);
184 
185 	/* build sm */
186 	si->base_mem += sizeof(struct f2fs_sm_info);
187 
188 	/* build sit */
189 	si->base_mem += sizeof(struct sit_info);
190 	si->base_mem += MAIN_SEGS(sbi) * sizeof(struct seg_entry);
191 	si->base_mem += f2fs_bitmap_size(MAIN_SEGS(sbi));
192 	si->base_mem += 2 * SIT_VBLOCK_MAP_SIZE * MAIN_SEGS(sbi);
193 	if (f2fs_discard_en(sbi))
194 		si->base_mem += SIT_VBLOCK_MAP_SIZE * MAIN_SEGS(sbi);
195 	si->base_mem += SIT_VBLOCK_MAP_SIZE;
196 	if (sbi->segs_per_sec > 1)
197 		si->base_mem += MAIN_SECS(sbi) * sizeof(struct sec_entry);
198 	si->base_mem += __bitmap_size(sbi, SIT_BITMAP);
199 
200 	/* build free segmap */
201 	si->base_mem += sizeof(struct free_segmap_info);
202 	si->base_mem += f2fs_bitmap_size(MAIN_SEGS(sbi));
203 	si->base_mem += f2fs_bitmap_size(MAIN_SECS(sbi));
204 
205 	/* build curseg */
206 	si->base_mem += sizeof(struct curseg_info) * NR_CURSEG_TYPE;
207 	si->base_mem += PAGE_SIZE * NR_CURSEG_TYPE;
208 
209 	/* build dirty segmap */
210 	si->base_mem += sizeof(struct dirty_seglist_info);
211 	si->base_mem += NR_DIRTY_TYPE * f2fs_bitmap_size(MAIN_SEGS(sbi));
212 	si->base_mem += f2fs_bitmap_size(MAIN_SECS(sbi));
213 
214 	/* build nm */
215 	si->base_mem += sizeof(struct f2fs_nm_info);
216 	si->base_mem += __bitmap_size(sbi, NAT_BITMAP);
217 	si->base_mem += (NM_I(sbi)->nat_bits_blocks << F2FS_BLKSIZE_BITS);
218 	si->base_mem += NM_I(sbi)->nat_blocks * NAT_ENTRY_BITMAP_SIZE;
219 	si->base_mem += NM_I(sbi)->nat_blocks / 8;
220 	si->base_mem += NM_I(sbi)->nat_blocks * sizeof(unsigned short);
221 
222 get_cache:
223 	si->cache_mem = 0;
224 
225 	/* build gc */
226 	if (sbi->gc_thread)
227 		si->cache_mem += sizeof(struct f2fs_gc_kthread);
228 
229 	/* build merge flush thread */
230 	if (SM_I(sbi)->fcc_info)
231 		si->cache_mem += sizeof(struct flush_cmd_control);
232 	if (SM_I(sbi)->dcc_info) {
233 		si->cache_mem += sizeof(struct discard_cmd_control);
234 		si->cache_mem += sizeof(struct discard_cmd) *
235 			atomic_read(&SM_I(sbi)->dcc_info->discard_cmd_cnt);
236 	}
237 
238 	/* free nids */
239 	si->cache_mem += (NM_I(sbi)->nid_cnt[FREE_NID] +
240 				NM_I(sbi)->nid_cnt[PREALLOC_NID]) *
241 				sizeof(struct free_nid);
242 	si->cache_mem += NM_I(sbi)->nat_cnt * sizeof(struct nat_entry);
243 	si->cache_mem += NM_I(sbi)->dirty_nat_cnt *
244 					sizeof(struct nat_entry_set);
245 	si->cache_mem += si->inmem_pages * sizeof(struct inmem_pages);
246 	for (i = 0; i < MAX_INO_ENTRY; i++)
247 		si->cache_mem += sbi->im[i].ino_num * sizeof(struct ino_entry);
248 	si->cache_mem += atomic_read(&sbi->total_ext_tree) *
249 						sizeof(struct extent_tree);
250 	si->cache_mem += atomic_read(&sbi->total_ext_node) *
251 						sizeof(struct extent_node);
252 
253 	si->page_mem = 0;
254 	npages = NODE_MAPPING(sbi)->nrpages;
255 	si->page_mem += (unsigned long long)npages << PAGE_SHIFT;
256 	npages = META_MAPPING(sbi)->nrpages;
257 	si->page_mem += (unsigned long long)npages << PAGE_SHIFT;
258 }
259 
260 static int stat_show(struct seq_file *s, void *v)
261 {
262 	struct f2fs_stat_info *si;
263 	int i = 0;
264 	int j;
265 
266 	mutex_lock(&f2fs_stat_mutex);
267 	list_for_each_entry(si, &f2fs_stat_list, stat_list) {
268 		update_general_status(si->sbi);
269 
270 		seq_printf(s, "\n=====[ partition info(%pg). #%d, %s, CP: %s]=====\n",
271 			si->sbi->sb->s_bdev, i++,
272 			f2fs_readonly(si->sbi->sb) ? "RO": "RW",
273 			f2fs_cp_error(si->sbi) ? "Error": "Good");
274 		seq_printf(s, "[SB: 1] [CP: 2] [SIT: %d] [NAT: %d] ",
275 			   si->sit_area_segs, si->nat_area_segs);
276 		seq_printf(s, "[SSA: %d] [MAIN: %d",
277 			   si->ssa_area_segs, si->main_area_segs);
278 		seq_printf(s, "(OverProv:%d Resv:%d)]\n\n",
279 			   si->overp_segs, si->rsvd_segs);
280 		if (test_opt(si->sbi, DISCARD))
281 			seq_printf(s, "Utilization: %u%% (%u valid blocks, %u discard blocks)\n",
282 				si->utilization, si->valid_count, si->discard_blks);
283 		else
284 			seq_printf(s, "Utilization: %u%% (%u valid blocks)\n",
285 				si->utilization, si->valid_count);
286 
287 		seq_printf(s, "  - Node: %u (Inode: %u, ",
288 			   si->valid_node_count, si->valid_inode_count);
289 		seq_printf(s, "Other: %u)\n  - Data: %u\n",
290 			   si->valid_node_count - si->valid_inode_count,
291 			   si->valid_count - si->valid_node_count);
292 		seq_printf(s, "  - Inline_xattr Inode: %u\n",
293 			   si->inline_xattr);
294 		seq_printf(s, "  - Inline_data Inode: %u\n",
295 			   si->inline_inode);
296 		seq_printf(s, "  - Inline_dentry Inode: %u\n",
297 			   si->inline_dir);
298 		seq_printf(s, "  - Orphan/Append/Update Inode: %u, %u, %u\n",
299 			   si->orphans, si->append, si->update);
300 		seq_printf(s, "\nMain area: %d segs, %d secs %d zones\n",
301 			   si->main_area_segs, si->main_area_sections,
302 			   si->main_area_zones);
303 		seq_printf(s, "  - COLD  data: %d, %d, %d\n",
304 			   si->curseg[CURSEG_COLD_DATA],
305 			   si->cursec[CURSEG_COLD_DATA],
306 			   si->curzone[CURSEG_COLD_DATA]);
307 		seq_printf(s, "  - WARM  data: %d, %d, %d\n",
308 			   si->curseg[CURSEG_WARM_DATA],
309 			   si->cursec[CURSEG_WARM_DATA],
310 			   si->curzone[CURSEG_WARM_DATA]);
311 		seq_printf(s, "  - HOT   data: %d, %d, %d\n",
312 			   si->curseg[CURSEG_HOT_DATA],
313 			   si->cursec[CURSEG_HOT_DATA],
314 			   si->curzone[CURSEG_HOT_DATA]);
315 		seq_printf(s, "  - Dir   dnode: %d, %d, %d\n",
316 			   si->curseg[CURSEG_HOT_NODE],
317 			   si->cursec[CURSEG_HOT_NODE],
318 			   si->curzone[CURSEG_HOT_NODE]);
319 		seq_printf(s, "  - File   dnode: %d, %d, %d\n",
320 			   si->curseg[CURSEG_WARM_NODE],
321 			   si->cursec[CURSEG_WARM_NODE],
322 			   si->curzone[CURSEG_WARM_NODE]);
323 		seq_printf(s, "  - Indir nodes: %d, %d, %d\n",
324 			   si->curseg[CURSEG_COLD_NODE],
325 			   si->cursec[CURSEG_COLD_NODE],
326 			   si->curzone[CURSEG_COLD_NODE]);
327 		seq_printf(s, "\n  - Valid: %d\n  - Dirty: %d\n",
328 			   si->main_area_segs - si->dirty_count -
329 			   si->prefree_count - si->free_segs,
330 			   si->dirty_count);
331 		seq_printf(s, "  - Prefree: %d\n  - Free: %d (%d)\n\n",
332 			   si->prefree_count, si->free_segs, si->free_secs);
333 		seq_printf(s, "CP calls: %d (BG: %d)\n",
334 				si->cp_count, si->bg_cp_count);
335 		seq_printf(s, "GC calls: %d (BG: %d)\n",
336 			   si->call_count, si->bg_gc);
337 		seq_printf(s, "  - data segments : %d (%d)\n",
338 				si->data_segs, si->bg_data_segs);
339 		seq_printf(s, "  - node segments : %d (%d)\n",
340 				si->node_segs, si->bg_node_segs);
341 		seq_printf(s, "Try to move %d blocks (BG: %d)\n", si->tot_blks,
342 				si->bg_data_blks + si->bg_node_blks);
343 		seq_printf(s, "  - data blocks : %d (%d)\n", si->data_blks,
344 				si->bg_data_blks);
345 		seq_printf(s, "  - node blocks : %d (%d)\n", si->node_blks,
346 				si->bg_node_blks);
347 		seq_printf(s, "Skipped : atomic write %llu (%llu)\n",
348 				si->skipped_atomic_files[BG_GC] +
349 				si->skipped_atomic_files[FG_GC],
350 				si->skipped_atomic_files[BG_GC]);
351 		seq_puts(s, "\nExtent Cache:\n");
352 		seq_printf(s, "  - Hit Count: L1-1:%llu L1-2:%llu L2:%llu\n",
353 				si->hit_largest, si->hit_cached,
354 				si->hit_rbtree);
355 		seq_printf(s, "  - Hit Ratio: %llu%% (%llu / %llu)\n",
356 				!si->total_ext ? 0 :
357 				div64_u64(si->hit_total * 100, si->total_ext),
358 				si->hit_total, si->total_ext);
359 		seq_printf(s, "  - Inner Struct Count: tree: %d(%d), node: %d\n",
360 				si->ext_tree, si->zombie_tree, si->ext_node);
361 		seq_puts(s, "\nBalancing F2FS Async:\n");
362 		seq_printf(s, "  - IO (CP: %4d, Data: %4d, Flush: (%4d %4d %4d), "
363 			"Discard: (%4d %4d)) cmd: %4d undiscard:%4u\n",
364 			   si->nr_wb_cp_data, si->nr_wb_data,
365 			   si->nr_flushing, si->nr_flushed,
366 			   si->flush_list_empty,
367 			   si->nr_discarding, si->nr_discarded,
368 			   si->nr_discard_cmd, si->undiscard_blks);
369 		seq_printf(s, "  - inmem: %4d, atomic IO: %4d (Max. %4d), "
370 			"volatile IO: %4d (Max. %4d)\n",
371 			   si->inmem_pages, si->aw_cnt, si->max_aw_cnt,
372 			   si->vw_cnt, si->max_vw_cnt);
373 		seq_printf(s, "  - nodes: %4d in %4d\n",
374 			   si->ndirty_node, si->node_pages);
375 		seq_printf(s, "  - dents: %4d in dirs:%4d (%4d)\n",
376 			   si->ndirty_dent, si->ndirty_dirs, si->ndirty_all);
377 		seq_printf(s, "  - datas: %4d in files:%4d\n",
378 			   si->ndirty_data, si->ndirty_files);
379 		seq_printf(s, "  - quota datas: %4d in quota files:%4d\n",
380 			   si->ndirty_qdata, si->nquota_files);
381 		seq_printf(s, "  - meta: %4d in %4d\n",
382 			   si->ndirty_meta, si->meta_pages);
383 		seq_printf(s, "  - imeta: %4d\n",
384 			   si->ndirty_imeta);
385 		seq_printf(s, "  - NATs: %9d/%9d\n  - SITs: %9d/%9d\n",
386 			   si->dirty_nats, si->nats, si->dirty_sits, si->sits);
387 		seq_printf(s, "  - free_nids: %9d/%9d\n  - alloc_nids: %9d\n",
388 			   si->free_nids, si->avail_nids, si->alloc_nids);
389 		seq_puts(s, "\nDistribution of User Blocks:");
390 		seq_puts(s, " [ valid | invalid | free ]\n");
391 		seq_puts(s, "  [");
392 
393 		for (j = 0; j < si->util_valid; j++)
394 			seq_putc(s, '-');
395 		seq_putc(s, '|');
396 
397 		for (j = 0; j < si->util_invalid; j++)
398 			seq_putc(s, '-');
399 		seq_putc(s, '|');
400 
401 		for (j = 0; j < si->util_free; j++)
402 			seq_putc(s, '-');
403 		seq_puts(s, "]\n\n");
404 		seq_printf(s, "IPU: %u blocks\n", si->inplace_count);
405 		seq_printf(s, "SSR: %u blocks in %u segments\n",
406 			   si->block_count[SSR], si->segment_count[SSR]);
407 		seq_printf(s, "LFS: %u blocks in %u segments\n",
408 			   si->block_count[LFS], si->segment_count[LFS]);
409 
410 		/* segment usage info */
411 		update_sit_info(si->sbi);
412 		seq_printf(s, "\nBDF: %u, avg. vblocks: %u\n",
413 			   si->bimodal, si->avg_vblocks);
414 
415 		/* memory footprint */
416 		update_mem_info(si->sbi);
417 		seq_printf(s, "\nMemory: %llu KB\n",
418 			(si->base_mem + si->cache_mem + si->page_mem) >> 10);
419 		seq_printf(s, "  - static: %llu KB\n",
420 				si->base_mem >> 10);
421 		seq_printf(s, "  - cached: %llu KB\n",
422 				si->cache_mem >> 10);
423 		seq_printf(s, "  - paged : %llu KB\n",
424 				si->page_mem >> 10);
425 	}
426 	mutex_unlock(&f2fs_stat_mutex);
427 	return 0;
428 }
429 
430 static int stat_open(struct inode *inode, struct file *file)
431 {
432 	return single_open(file, stat_show, inode->i_private);
433 }
434 
435 static const struct file_operations stat_fops = {
436 	.owner = THIS_MODULE,
437 	.open = stat_open,
438 	.read = seq_read,
439 	.llseek = seq_lseek,
440 	.release = single_release,
441 };
442 
443 int f2fs_build_stats(struct f2fs_sb_info *sbi)
444 {
445 	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
446 	struct f2fs_stat_info *si;
447 
448 	si = f2fs_kzalloc(sbi, sizeof(struct f2fs_stat_info), GFP_KERNEL);
449 	if (!si)
450 		return -ENOMEM;
451 
452 	si->all_area_segs = le32_to_cpu(raw_super->segment_count);
453 	si->sit_area_segs = le32_to_cpu(raw_super->segment_count_sit);
454 	si->nat_area_segs = le32_to_cpu(raw_super->segment_count_nat);
455 	si->ssa_area_segs = le32_to_cpu(raw_super->segment_count_ssa);
456 	si->main_area_segs = le32_to_cpu(raw_super->segment_count_main);
457 	si->main_area_sections = le32_to_cpu(raw_super->section_count);
458 	si->main_area_zones = si->main_area_sections /
459 				le32_to_cpu(raw_super->secs_per_zone);
460 	si->sbi = sbi;
461 	sbi->stat_info = si;
462 
463 	atomic64_set(&sbi->total_hit_ext, 0);
464 	atomic64_set(&sbi->read_hit_rbtree, 0);
465 	atomic64_set(&sbi->read_hit_largest, 0);
466 	atomic64_set(&sbi->read_hit_cached, 0);
467 
468 	atomic_set(&sbi->inline_xattr, 0);
469 	atomic_set(&sbi->inline_inode, 0);
470 	atomic_set(&sbi->inline_dir, 0);
471 	atomic_set(&sbi->inplace_count, 0);
472 
473 	atomic_set(&sbi->aw_cnt, 0);
474 	atomic_set(&sbi->vw_cnt, 0);
475 	atomic_set(&sbi->max_aw_cnt, 0);
476 	atomic_set(&sbi->max_vw_cnt, 0);
477 
478 	mutex_lock(&f2fs_stat_mutex);
479 	list_add_tail(&si->stat_list, &f2fs_stat_list);
480 	mutex_unlock(&f2fs_stat_mutex);
481 
482 	return 0;
483 }
484 
485 void f2fs_destroy_stats(struct f2fs_sb_info *sbi)
486 {
487 	struct f2fs_stat_info *si = F2FS_STAT(sbi);
488 
489 	mutex_lock(&f2fs_stat_mutex);
490 	list_del(&si->stat_list);
491 	mutex_unlock(&f2fs_stat_mutex);
492 
493 	kfree(si);
494 }
495 
496 int __init f2fs_create_root_stats(void)
497 {
498 	struct dentry *file;
499 
500 	f2fs_debugfs_root = debugfs_create_dir("f2fs", NULL);
501 	if (!f2fs_debugfs_root)
502 		return -ENOMEM;
503 
504 	file = debugfs_create_file("status", S_IRUGO, f2fs_debugfs_root,
505 			NULL, &stat_fops);
506 	if (!file) {
507 		debugfs_remove(f2fs_debugfs_root);
508 		f2fs_debugfs_root = NULL;
509 		return -ENOMEM;
510 	}
511 
512 	return 0;
513 }
514 
515 void f2fs_destroy_root_stats(void)
516 {
517 	if (!f2fs_debugfs_root)
518 		return;
519 
520 	debugfs_remove_recursive(f2fs_debugfs_root);
521 	f2fs_debugfs_root = NULL;
522 }
523