fs/f2fs/debug.c - kernel/msm-4.9 - Gitiles

 /*
  * 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_dirs = sbi->ndirty_inode[DIR_INODE];
 	si->ndirty_files = sbi->ndirty_inode[FILE_INODE];
 	si->inmem_pages = get_pages(sbi, F2FS_INMEM_PAGES);
 	si->wb_pages = get_pages(sbi, F2FS_WRITEBACK);
 	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->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->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->fnids = NM_I(sbi)->fcnt;
 	si->bg_gc = sbi->bg_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] = curseg->segno / sbi->segs_per_sec;
 		si->curzone[i] = si->cursec[i] / sbi->secs_per_zone;
 	}

 	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 = sbi->segs_per_sec * sbi->blocks_per_seg;
 	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, sbi->segs_per_sec);
 		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;

 	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 += 3 * 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);

 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)->cmd_control_info)
 		si->cache_mem += sizeof(struct flush_cmd_control);

 	/* free nids */
 	si->cache_mem += NM_I(sbi)->fcnt * 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 <= UPDATE_INO; 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 ]=====\n",
 			si->sbi->sb->s_bdev, i++);
 		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);
 		seq_printf(s, "Utilization: %d%% (%d 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, "\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_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, "  - inmem: %4d, wb: %4d\n",
 			   si->inmem_pages, si->wb_pages);
 		seq_printf(s, "  - nodes: %4d in %4d\n",
 			   si->ndirty_node, si->node_pages);
 		seq_printf(s, "  - dents: %4d in dirs:%4d\n",
 			   si->ndirty_dent, si->ndirty_dirs);
 		seq_printf(s, "  - datas: %4d in files:%4d\n",
 			   si->ndirty_data, si->ndirty_files);
 		seq_printf(s, "  - meta: %4d in %4d\n",
 			   si->ndirty_meta, si->meta_pages);
 		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\n",
 			   si->fnids);
 		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 = {
 	.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 = kzalloc(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);

 	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;
 }
	/*
	* 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_dirs = sbi->ndirty_inode[DIR_INODE];
	si->ndirty_files = sbi->ndirty_inode[FILE_INODE];
	si->inmem_pages = get_pages(sbi, F2FS_INMEM_PAGES);
	si->wb_pages = get_pages(sbi, F2FS_WRITEBACK);
	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->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->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->fnids = NM_I(sbi)->fcnt;
	si->bg_gc = sbi->bg_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] = curseg->segno / sbi->segs_per_sec;
	si->curzone[i] = si->cursec[i] / sbi->secs_per_zone;
	}

	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 = sbi->segs_per_sec * sbi->blocks_per_seg;
	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, sbi->segs_per_sec);
	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;

	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 += 3 * 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);

	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)->cmd_control_info)
	si->cache_mem += sizeof(struct flush_cmd_control);

	/* free nids */
	si->cache_mem += NM_I(sbi)->fcnt * 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 <= UPDATE_INO; 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 ]=====\n",
	si->sbi->sb->s_bdev, i++);
	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);
	seq_printf(s, "Utilization: %d%% (%d 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, "\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_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, " - inmem: %4d, wb: %4d\n",
	si->inmem_pages, si->wb_pages);
	seq_printf(s, " - nodes: %4d in %4d\n",
	si->ndirty_node, si->node_pages);
	seq_printf(s, " - dents: %4d in dirs:%4d\n",
	si->ndirty_dent, si->ndirty_dirs);
	seq_printf(s, " - datas: %4d in files:%4d\n",
	si->ndirty_data, si->ndirty_files);
	seq_printf(s, " - meta: %4d in %4d\n",
	si->ndirty_meta, si->meta_pages);
	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\n",
	si->fnids);
	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 = {
	.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 = kzalloc(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);

	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;
	}