kernel_optimize_test/fs
Linus Torvalds 3ddcd0569c vfs: optimize inode cache access patterns
The inode structure layout is largely random, and some of the vfs paths
really do care.  The path lookup in particular is already quite D$
intensive, and profiles show that accessing the 'inode->i_op->xyz'
fields is quite costly.

We already optimized the dcache to not unnecessarily load the d_op
structure for members that are often NULL using the DCACHE_OP_xyz bits
in dentry->d_flags, and this does something very similar for the inode
ops that are used during pathname lookup.

It also re-orders the fields so that the fields accessed by 'stat' are
together at the beginning of the inode structure, and roughly in the
order accessed.

The effect of this seems to be in the 1-2% range for an empty kernel
"make -j" run (which is fairly kernel-intensive, mostly in filename
lookup), so it's visible.  The numbers are fairly noisy, though, and
likely depend a lot on exact microarchitecture.  So there's more tuning
to be done.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-06 22:53:23 -07:00
..
9p switch posix_acl_equiv_mode() to umode_t * 2011-08-01 02:10:06 -04:00
adfs
affs fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers 2011-07-20 20:47:59 -04:00
afs AFS: Fix silly characters in a comment 2011-07-20 20:48:03 -04:00
autofs4 autofs4: bogus dentry_unhash() added in ->unlink() 2011-05-30 01:50:53 -04:00
befs
bfs bfs: remove unnecessary dentry_unhash on dir rename 2011-05-28 01:02:50 -04:00
btrfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable 2011-08-02 21:14:05 -10:00
cachefiles kill useless checks for sb->s_op == NULL 2011-07-20 01:44:21 -04:00
ceph Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client 2011-07-26 13:38:50 -07:00
cifs cifs: cope with negative dentries in cifs_get_root 2011-08-05 15:03:09 +00:00
coda fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers 2011-07-20 20:47:59 -04:00
configfs configfs: remove unnecessary dentry_unhash on rmdir, dir rename 2011-05-28 01:02:54 -04:00
cramfs cramfs: get_cramfs_inode() returns ERR_PTR() on failure 2011-07-17 23:22:02 -04:00
debugfs
devpts
dlm Merge branch 'for-3.1' of git://linux-nfs.org/~bfields/linux 2011-07-25 22:49:19 -07:00
ecryptfs ecryptfs: Make inode bdi consistent with superblock bdi 2011-07-28 23:48:26 -05:00
efs make d_splice_alias(ERR_PTR(err), dentry) = ERR_PTR(err) 2011-07-20 01:44:26 -04:00
exofs fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers 2011-07-20 20:47:59 -04:00
exportfs
ext2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2011-08-01 13:48:31 -10:00
ext3 switch posix_acl_equiv_mode() to umode_t * 2011-08-01 02:10:06 -04:00
ext4 ext4: use kzalloc in ext4_kzalloc() 2011-08-03 14:57:11 -04:00
fat fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers 2011-07-20 20:47:59 -04:00
freevxfs
fscache FS-Cache: Fix __fscache_uncache_all_inode_pages()'s outer loop 2011-07-21 10:59:16 -07:00
fuse Merge branch 'for-3.1' of git://linux-nfs.org/~bfields/linux 2011-07-25 22:49:19 -07:00
gfs2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2011-08-01 13:48:31 -10:00
hfs fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers 2011-07-20 20:47:59 -04:00
hfsplus Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2011-07-22 19:02:39 -07:00
hostfs fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers 2011-07-20 20:47:59 -04:00
hpfs fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers 2011-07-20 20:47:59 -04:00
hppfs hppfs: missing include 2011-07-27 22:21:58 -04:00
hugetlbfs Merge 'akpm' patch series 2011-07-25 21:00:19 -07:00
isofs isofs: Remove global fs lock 2011-07-22 19:42:12 -04:00
jbd jbd: Use WRITE_SYNC in journal checkpoint. 2011-06-28 00:06:41 +02:00
jbd2 jbd2: remove jbd2_dev_to_name() from jbd2 tracepoints 2011-07-10 22:05:08 -04:00
jffs2 switch posix_acl_equiv_mode() to umode_t * 2011-08-01 02:10:06 -04:00
jfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2011-08-01 13:48:31 -10:00
lockd Merge branch 'nfs-for-3.1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs 2011-07-27 13:23:02 -07:00
logfs fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers 2011-07-20 20:47:59 -04:00
minix minix_getattr(): don't bother with ->d_parent 2011-07-20 20:47:53 -04:00
ncpfs fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers 2011-07-20 20:47:59 -04:00
nfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2011-08-01 13:48:31 -10:00
nfs_common
nfsd Merge branch 'for-3.1' of git://linux-nfs.org/~bfields/linux 2011-07-25 22:49:19 -07:00
nilfs2 fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers 2011-07-20 20:47:59 -04:00
nls
notify atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
ntfs atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
ocfs2 switch posix_acl_equiv_mode() to umode_t * 2011-08-01 02:10:06 -04:00
omfs omfs: fix (mode & S_IFDIR) abuse 2011-07-26 13:05:28 -04:00
openpromfs
partitions Merge branch 'for-linus' into for-3.1/core 2011-07-01 16:17:13 +02:00
proc vfs: show O_CLOEXE bit properly in /proc/<pid>/fdinfo/<fd> files 2011-08-06 11:51:33 -07:00
pstore pstore: Allow the user to explicitly choose a backend 2011-07-22 16:14:39 -07:00
qnx4
quota
ramfs
reiserfs switch posix_acl_equiv_mode() to umode_t * 2011-08-01 02:10:06 -04:00
romfs romfs: fix romfs_get_unmapped_area() argument check 2011-06-27 18:00:12 -07:00
squashfs Merge git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linus 2011-07-25 22:50:35 -07:00
sysfs ->permission() sanitizing: don't pass flags to ->permission() 2011-07-20 01:43:24 -04:00
sysv sysv: remove unnecessary dentry_unhash from rmdir, dir rename 2011-05-28 01:02:50 -04:00
ubifs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2011-07-22 19:02:39 -07:00
udf switch udf_ioctl() to inode_permission() 2011-07-20 01:43:07 -04:00
ufs make d_splice_alias(ERR_PTR(err), dentry) = ERR_PTR(err) 2011-07-20 01:44:26 -04:00
xfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2011-08-01 13:48:31 -10:00
aio.c
anon_inodes.c vfs: dont chain pipe/anon/socket on superblock s_inodes list 2011-07-26 12:57:09 -04:00
attr.c fs: move inode_dio_wait calls into ->setattr 2011-07-20 20:47:47 -04:00
bad_inode.c fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers 2011-07-20 20:47:59 -04:00
binfmt_aout.c
binfmt_elf_fdpic.c consolidate BINPRM_FLAGS_ENFORCE_NONDUMP handling 2011-07-20 01:43:10 -04:00
binfmt_elf.c consolidate BINPRM_FLAGS_ENFORCE_NONDUMP handling 2011-07-20 01:43:10 -04:00
binfmt_em86.c
binfmt_flat.c
binfmt_misc.c consolidate BINPRM_FLAGS_ENFORCE_NONDUMP handling 2011-07-20 01:43:10 -04:00
binfmt_script.c
binfmt_som.c
bio-integrity.c
bio.c block: improve the bio_add_page() and bio_add_pc_page() descriptions 2011-05-28 14:44:46 +02:00
block_dev.c fix block device fallout from ->fsync() changes 2011-08-01 21:33:47 -04:00
buffer.c vfs: Fix data corruption after failed write in __block_write_begin() 2011-06-16 11:44:46 -04:00
char_dev.c
compat_binfmt_elf.c
compat_ioctl.c compat_ioctl: fix warning caused by qemu 2011-07-01 22:32:26 +02:00
compat.c nfsd: Remove deprecated nfsctl system call and related code. 2011-07-15 18:58:42 -04:00
dcache.c vfs: renumber DCACHE_xyz flags, remove some stale ones 2011-08-06 22:52:40 -07:00
dcookies.c oprofile, dcookies: Fix possible circular locking dependency 2011-05-31 16:33:35 +02:00
direct-io.c atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
drop_caches.c
eventfd.c
eventpoll.c atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
exec.c fs/exec.c:acct_arg_size(): ptl is no longer needed for add_mm_counter() 2011-07-26 16:49:44 -07:00
fcntl.c
fhandle.c
fifo.c
file_table.c atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
file.c
filesystems.c
fs_struct.c
fs-writeback.c don't busy retry the inode on failed grab_super_passive() 2011-07-31 22:52:08 +08:00
generic_acl.c switch posix_acl_equiv_mode() to umode_t * 2011-08-01 02:10:06 -04:00
inode.c vfs: optimize inode cache access patterns 2011-08-06 22:53:23 -07:00
internal.h superblock: move pin_sb_for_writeback() to fs/super.c 2011-07-20 01:44:38 -04:00
ioctl.c
ioprio.c
Kconfig tmpfs: expand "help" to explain value of TMPFS_POSIX_ACL 2011-08-03 14:25:25 -10:00
Kconfig.binfmt
libfs.c fix IN_DELETE_SELF on overwriting rename() on ramfs et.al. 2011-07-22 19:42:11 -04:00
locks.c locks: rename lock-manager ops 2011-07-20 20:23:19 -04:00
Makefile nfsd: Remove deprecated nfsctl system call and related code. 2011-07-15 18:58:42 -04:00
mbcache.c
mpage.c
namei.c vfs: optimize inode cache access patterns 2011-08-06 22:53:23 -07:00
namespace.c VFS : mount lock scalability for internal mounts 2011-07-24 10:08:32 -04:00
no-block.c
open.c merge fchmod() and fchmodat() guts, kill ancient broken kludge 2011-07-26 15:07:43 -04:00
pipe.c vfs: dont chain pipe/anon/socket on superblock s_inodes list 2011-07-26 12:57:09 -04:00
pnode.c
pnode.h
posix_acl.c switch posix_acl_chmod() to umode_t 2011-08-01 02:10:32 -04:00
read_write.c fs: add missing unlock in default_llseek() 2011-07-26 12:57:09 -04:00
read_write.h
readdir.c
select.c
seq_file.c
signalfd.c
splice.c tmpfs: clone shmem_file_splice_read() 2011-07-25 20:57:11 -07:00
stack.c mm: a few small updates for radix-swap 2011-08-03 14:25:24 -10:00
stat.c vfs: optimize inode cache access patterns 2011-08-06 22:53:23 -07:00
statfs.c
super.c Merge branch 'for-3.1/core' of git://git.kernel.dk/linux-block 2011-07-25 10:33:36 -07:00
sync.c fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers 2011-07-20 20:47:59 -04:00
timerfd.c timerfd: Fix wakeup of processes when timer is cancelled on clock change 2011-06-14 11:46:14 +02:00
utimes.c
xattr_acl.c
xattr.c Cache xattr security drop check for write v2 2011-05-28 12:02:09 -04:00