kernel_optimize_test/include/linux/ext4_fs_sb.h
Badari Pulavarty 5e70030d4c ext4: statfs speed up
This is a patch that speeds up statfs.  It is very simple - the "overhead"
calculation, which takes a huge amount of time for large filesystems, never
changes unless the size of the filesystem itself changes.  That means we can
store it in memory and only recalculate if the filesystem has been resized
(almost never).

It also fixes a minor problem that we never update the on-disk superblock free
blocks/inodes counts until the filesystem is unmounted.  While not fatal, we
may as well update that on disk when we have the information, and it makes
things like debugfs and dumpe2fs report a bit more accurate info.

Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Andreas Dilger <adilger@clusterfs.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 09:05:52 -07:00

97 lines
3.1 KiB
C

/*
* linux/include/linux/ext4_fs_sb.h
*
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
*
* from
*
* linux/include/linux/minix_fs_sb.h
*
* Copyright (C) 1991, 1992 Linus Torvalds
*/
#ifndef _LINUX_EXT4_FS_SB
#define _LINUX_EXT4_FS_SB
#ifdef __KERNEL__
#include <linux/timer.h>
#include <linux/wait.h>
#include <linux/blockgroup_lock.h>
#include <linux/percpu_counter.h>
#endif
#include <linux/rbtree.h>
/*
* third extended-fs super-block data in memory
*/
struct ext4_sb_info {
unsigned long s_frag_size; /* Size of a fragment in bytes */
unsigned long s_desc_size; /* Size of a group descriptor in bytes */
unsigned long s_frags_per_block;/* Number of fragments per block */
unsigned long s_inodes_per_block;/* Number of inodes per block */
unsigned long s_frags_per_group;/* Number of fragments in a group */
unsigned long s_blocks_per_group;/* Number of blocks in a group */
unsigned long s_inodes_per_group;/* Number of inodes in a group */
unsigned long s_itb_per_group; /* Number of inode table blocks per group */
unsigned long s_gdb_count; /* Number of group descriptor blocks */
unsigned long s_desc_per_block; /* Number of group descriptors per block */
unsigned long s_groups_count; /* Number of groups in the fs */
unsigned long s_overhead_last; /* Last calculated overhead */
unsigned long s_blocks_last; /* Last seen block count */
struct buffer_head * s_sbh; /* Buffer containing the super block */
struct ext4_super_block * s_es; /* Pointer to the super block in the buffer */
struct buffer_head ** s_group_desc;
unsigned long s_mount_opt;
uid_t s_resuid;
gid_t s_resgid;
unsigned short s_mount_state;
unsigned short s_pad;
int s_addr_per_block_bits;
int s_desc_per_block_bits;
int s_inode_size;
int s_first_ino;
spinlock_t s_next_gen_lock;
u32 s_next_generation;
u32 s_hash_seed[4];
int s_def_hash_version;
struct percpu_counter s_freeblocks_counter;
struct percpu_counter s_freeinodes_counter;
struct percpu_counter s_dirs_counter;
struct blockgroup_lock s_blockgroup_lock;
/* root of the per fs reservation window tree */
spinlock_t s_rsv_window_lock;
struct rb_root s_rsv_window_root;
struct ext4_reserve_window_node s_rsv_window_head;
/* Journaling */
struct inode * s_journal_inode;
struct journal_s * s_journal;
struct list_head s_orphan;
unsigned long s_commit_interval;
struct block_device *journal_bdev;
#ifdef CONFIG_JBD_DEBUG
struct timer_list turn_ro_timer; /* For turning read-only (crash simulation) */
wait_queue_head_t ro_wait_queue; /* For people waiting for the fs to go read-only */
#endif
#ifdef CONFIG_QUOTA
char *s_qf_names[MAXQUOTAS]; /* Names of quota files with journalled quota */
int s_jquota_fmt; /* Format of quota to use */
#endif
#ifdef EXTENTS_STATS
/* ext4 extents stats */
unsigned long s_ext_min;
unsigned long s_ext_max;
unsigned long s_depth_max;
spinlock_t s_ext_stats_lock;
unsigned long s_ext_blocks;
unsigned long s_ext_extents;
#endif
};
#endif /* _LINUX_EXT4_FS_SB */